Stripped down version of Segundos NetService library (http://mbed.org/users/segundo/libraries/NetServices ). I have removed all NetServices, and all functions which had been disabled. Use this version when you need only pure TCP or UDP functions - this library compiles faster.

Dependencies:   lwip lwip-sys

Dependents:   christmasLights device_server pop3demo device_server_udp ... more

Files at this revision

API Documentation at this revision

Comitter:
hlipka
Date:
Mon Jan 10 21:03:11 2011 +0000
Child:
1:9d93f4dc2f46
Commit message:
initial version

Changed in this revision

api/DNSRequest.cpp Show annotated file Show diff for this revision Revisions of this file
api/DNSRequest.h Show annotated file Show diff for this revision Revisions of this file
api/TCPSocket.cpp Show annotated file Show diff for this revision Revisions of this file
api/TCPSocket.h Show annotated file Show diff for this revision Revisions of this file
api/UDPSocket.cpp Show annotated file Show diff for this revision Revisions of this file
api/UDPSocket.h Show annotated file Show diff for this revision Revisions of this file
core/host.h Show annotated file Show diff for this revision Revisions of this file
core/ipaddr.cpp Show annotated file Show diff for this revision Revisions of this file
core/ipaddr.h Show annotated file Show diff for this revision Revisions of this file
core/net.cpp Show annotated file Show diff for this revision Revisions of this file
core/net.h Show annotated file Show diff for this revision Revisions of this file
core/netservice.cpp Show annotated file Show diff for this revision Revisions of this file
core/netservice.h Show annotated file Show diff for this revision Revisions of this file
dbg/dbg.cpp Show annotated file Show diff for this revision Revisions of this file
dbg/dbg.h Show annotated file Show diff for this revision Revisions of this file
drv/eth/eth_drv.cpp Show annotated file Show diff for this revision Revisions of this file
drv/eth/eth_drv.h Show annotated file Show diff for this revision Revisions of this file
if/eth/EthernetNetIf.cpp Show annotated file Show diff for this revision Revisions of this file
if/eth/EthernetNetIf.h Show annotated file Show diff for this revision Revisions of this file
if/lwip/LwipNetIf.cpp Show annotated file Show diff for this revision Revisions of this file
if/lwip/LwipNetIf.h Show annotated file Show diff for this revision Revisions of this file
if/lwip/lwipNetDnsRequest.cpp Show annotated file Show diff for this revision Revisions of this file
if/lwip/lwipNetDnsRequest.h Show annotated file Show diff for this revision Revisions of this file
if/lwip/lwipNetTcpSocket.cpp Show annotated file Show diff for this revision Revisions of this file
if/lwip/lwipNetTcpSocket.h Show annotated file Show diff for this revision Revisions of this file
if/lwip/lwipNetUdpSocket.cpp Show annotated file Show diff for this revision Revisions of this file
if/lwip/lwipNetUdpSocket.h Show annotated file Show diff for this revision Revisions of this file
if/net/netdnsrequest.cpp Show annotated file Show diff for this revision Revisions of this file
if/net/netdnsrequest.h Show annotated file Show diff for this revision Revisions of this file
if/net/netif.cpp Show annotated file Show diff for this revision Revisions of this file
if/net/netif.h Show annotated file Show diff for this revision Revisions of this file
if/net/nettcpsocket.cpp Show annotated file Show diff for this revision Revisions of this file
if/net/nettcpsocket.h Show annotated file Show diff for this revision Revisions of this file
if/net/netudpsocket.cpp Show annotated file Show diff for this revision Revisions of this file
if/net/netudpsocket.h Show annotated file Show diff for this revision Revisions of this file
lwip/arch/cc.h Show annotated file Show diff for this revision Revisions of this file
lwip/arch/perf.h Show annotated file Show diff for this revision Revisions of this file
lwip/arch/sys_arch.cpp Show annotated file Show diff for this revision Revisions of this file
lwip/arch/sys_arch.h Show annotated file Show diff for this revision Revisions of this file
lwip/core/def.c Show annotated file Show diff for this revision Revisions of this file
lwip/core/dhcp.c Show annotated file Show diff for this revision Revisions of this file
lwip/core/dns.c Show annotated file Show diff for this revision Revisions of this file
lwip/core/init.c Show annotated file Show diff for this revision Revisions of this file
lwip/core/ipv4/icmp.c Show annotated file Show diff for this revision Revisions of this file
lwip/core/ipv4/igmp.c Show annotated file Show diff for this revision Revisions of this file
lwip/core/ipv4/inet.c Show annotated file Show diff for this revision Revisions of this file
lwip/core/ipv4/inet_chksum.c Show annotated file Show diff for this revision Revisions of this file
lwip/core/ipv4/ip.c Show annotated file Show diff for this revision Revisions of this file
lwip/core/ipv4/ip_addr.c Show annotated file Show diff for this revision Revisions of this file
lwip/core/ipv4/ip_frag.c Show annotated file Show diff for this revision Revisions of this file
lwip/core/mem.c Show annotated file Show diff for this revision Revisions of this file
lwip/core/memp.c Show annotated file Show diff for this revision Revisions of this file
lwip/core/netif.c Show annotated file Show diff for this revision Revisions of this file
lwip/core/pbuf.c Show annotated file Show diff for this revision Revisions of this file
lwip/core/stats.c Show annotated file Show diff for this revision Revisions of this file
lwip/core/sys.c Show annotated file Show diff for this revision Revisions of this file
lwip/core/tcp.c Show annotated file Show diff for this revision Revisions of this file
lwip/core/tcp_in.c Show annotated file Show diff for this revision Revisions of this file
lwip/core/tcp_out.c Show annotated file Show diff for this revision Revisions of this file
lwip/core/timers.c Show annotated file Show diff for this revision Revisions of this file
lwip/core/udp.c Show annotated file Show diff for this revision Revisions of this file
lwip/include/ipv4/lwip/autoip.h Show annotated file Show diff for this revision Revisions of this file
lwip/include/ipv4/lwip/icmp.h Show annotated file Show diff for this revision Revisions of this file
lwip/include/ipv4/lwip/igmp.h Show annotated file Show diff for this revision Revisions of this file
lwip/include/ipv4/lwip/inet.h Show annotated file Show diff for this revision Revisions of this file
lwip/include/ipv4/lwip/inet_chksum.h Show annotated file Show diff for this revision Revisions of this file
lwip/include/ipv4/lwip/ip.h Show annotated file Show diff for this revision Revisions of this file
lwip/include/ipv4/lwip/ip_addr.h Show annotated file Show diff for this revision Revisions of this file
lwip/include/ipv4/lwip/ip_frag.h Show annotated file Show diff for this revision Revisions of this file
lwip/include/lwip/api.h Show annotated file Show diff for this revision Revisions of this file
lwip/include/lwip/api_msg.h Show annotated file Show diff for this revision Revisions of this file
lwip/include/lwip/arch.h Show annotated file Show diff for this revision Revisions of this file
lwip/include/lwip/debug.h Show annotated file Show diff for this revision Revisions of this file
lwip/include/lwip/def.h Show annotated file Show diff for this revision Revisions of this file
lwip/include/lwip/dhcp.h Show annotated file Show diff for this revision Revisions of this file
lwip/include/lwip/dns.h Show annotated file Show diff for this revision Revisions of this file
lwip/include/lwip/err.h Show annotated file Show diff for this revision Revisions of this file
lwip/include/lwip/init.h Show annotated file Show diff for this revision Revisions of this file
lwip/include/lwip/mem.h Show annotated file Show diff for this revision Revisions of this file
lwip/include/lwip/memp.h Show annotated file Show diff for this revision Revisions of this file
lwip/include/lwip/memp_std.h Show annotated file Show diff for this revision Revisions of this file
lwip/include/lwip/netbuf.h Show annotated file Show diff for this revision Revisions of this file
lwip/include/lwip/netdb.h Show annotated file Show diff for this revision Revisions of this file
lwip/include/lwip/netif.h Show annotated file Show diff for this revision Revisions of this file
lwip/include/lwip/netifapi.h Show annotated file Show diff for this revision Revisions of this file
lwip/include/lwip/opt.h Show annotated file Show diff for this revision Revisions of this file
lwip/include/lwip/pbuf.h Show annotated file Show diff for this revision Revisions of this file
lwip/include/lwip/raw.h Show annotated file Show diff for this revision Revisions of this file
lwip/include/lwip/sio.h Show annotated file Show diff for this revision Revisions of this file
lwip/include/lwip/snmp.h Show annotated file Show diff for this revision Revisions of this file
lwip/include/lwip/snmp_asn1.h Show annotated file Show diff for this revision Revisions of this file
lwip/include/lwip/snmp_msg.h Show annotated file Show diff for this revision Revisions of this file
lwip/include/lwip/snmp_structs.h Show annotated file Show diff for this revision Revisions of this file
lwip/include/lwip/sockets.h Show annotated file Show diff for this revision Revisions of this file
lwip/include/lwip/stats.h Show annotated file Show diff for this revision Revisions of this file
lwip/include/lwip/sys.h Show annotated file Show diff for this revision Revisions of this file
lwip/include/lwip/tcp.h Show annotated file Show diff for this revision Revisions of this file
lwip/include/lwip/tcp_impl.h Show annotated file Show diff for this revision Revisions of this file
lwip/include/lwip/tcpip.h Show annotated file Show diff for this revision Revisions of this file
lwip/include/lwip/timers.h Show annotated file Show diff for this revision Revisions of this file
lwip/include/lwip/udp.h Show annotated file Show diff for this revision Revisions of this file
lwip/include/netif/etharp.h Show annotated file Show diff for this revision Revisions of this file
lwip/include/netif/ppp_oe.h Show annotated file Show diff for this revision Revisions of this file
lwip/include/netif/slipif.h Show annotated file Show diff for this revision Revisions of this file
lwip/lwipopts.h Show annotated file Show diff for this revision Revisions of this file
lwip/netif/etharp.c Show annotated file Show diff for this revision Revisions of this file
lwip/netif/ethernetif.c Show annotated file Show diff for this revision Revisions of this file
netCfg.h Show annotated file Show diff for this revision Revisions of this file
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/api/DNSRequest.cpp	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,115 @@
+
+/*
+Copyright (c) 2010 Donatien Garnier (donatiengar [at] gmail [dot] com)
+ 
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+ 
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+ 
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+#include "DNSRequest.h"
+#include "if/net/netdnsrequest.h"
+
+DNSRequest::DNSRequest() : m_pNetDnsRequest(NULL), m_pCbItem(NULL), m_pCbMeth(NULL), m_pCb(NULL)
+{
+
+}
+
+DNSRequest::~DNSRequest()
+{
+  close();
+}
+  
+DNSRequestErr DNSRequest::resolve(const char* hostname)
+{
+  if(!m_pNetDnsRequest)
+  {
+    m_pNetDnsRequest = Net::dnsRequest(hostname);
+    if(!m_pNetDnsRequest)
+    {
+      return DNS_IF; //Interface did not return a NetDnsRequest (usually because a default interface does not exist)
+    }
+    m_pNetDnsRequest->setOnReply(this, &DNSRequest::onNetDnsReply);
+    return DNS_OK;
+  }
+  else
+  {
+    return DNS_INUSE; //The previous req has not completed
+  }
+}
+
+DNSRequestErr DNSRequest::resolve(Host* pHost)
+{
+  if(!m_pNetDnsRequest)
+  {
+    m_pNetDnsRequest = Net::dnsRequest(pHost);
+    if(!m_pNetDnsRequest)
+    {
+      return DNS_IF; //Interface did not return a NetDnsRequest (usually because a default interface does not exist)
+    }
+    m_pNetDnsRequest->setOnReply(this, &DNSRequest::onNetDnsReply);
+    return DNS_OK;
+  }
+  else
+  {
+    return DNS_INUSE; //The previous req has not completed
+  }
+}
+
+//Callbacks
+void DNSRequest::setOnReply( void (*pMethod)(DNSReply) )
+{
+  m_pCb = pMethod;
+}
+
+#if 0 //For doc only
+template<class T> 
+void DNSRequest::setOnReply( T* pItem, void (T::*pMethod)(DNSReply) )
+{
+  m_pCbItem = (CDummy*) pItem;
+  m_pCbMeth = (void (CDummy::*)(DNSReply)) pMethod;
+}
+#endif
+
+DNSRequestErr DNSRequest::getResult(IpAddr* pIp)
+{
+  if(!m_pNetDnsRequest)
+  {
+    return DNS_SETUP;
+  }
+  m_pNetDnsRequest->getResult(pIp);
+  return DNS_OK;
+}
+  
+DNSRequestErr DNSRequest::close()
+{
+  if(!m_pNetDnsRequest)
+  {
+    return DNS_SETUP;
+  }
+  m_pNetDnsRequest->close();
+  m_pNetDnsRequest = NULL;
+  return DNS_OK;
+}
+  
+void DNSRequest::onNetDnsReply(NetDnsReply r)
+{
+  if(m_pCbItem && m_pCbMeth)
+    (m_pCbItem->*m_pCbMeth)((DNSReply) r);
+  else if(m_pCb)
+    m_pCb((DNSReply) r);
+}
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/api/DNSRequest.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,131 @@
+
+/*
+Copyright (c) 2010 Donatien Garnier (donatiengar [at] gmail [dot] com)
+ 
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+ 
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+ 
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+/** \file
+DNS Request header file
+*/
+
+#ifndef DNSREQUEST_H
+#define DNSREQUEST_H
+
+#include "core/net.h"
+#include "core/ipaddr.h"
+#include "core/host.h"
+//Essentially it is a safe interface to NetDnsRequest
+
+///DNS Request error codes
+enum DNSRequestErr
+{
+  __DNS_MIN = -0xFFFF,
+  DNS_SETUP, ///<DNSRequest not properly configured
+  DNS_IF, ///<Interface has problems, does not exist or is not initialized
+  DNS_MEM, ///<Not enough mem
+  DNS_INUSE, ///<Interface / Port is in use
+  DNS_PROCESSING, ///<Request has not completed
+//...
+  DNS_OK = 0 ///<Success
+};
+
+///DNS Request Result Events
+enum DNSReply
+{
+  DNS_PRTCL,
+  DNS_NOTFOUND, ///Hostname is unknown
+  DNS_ERROR, ///Problem with DNS Service
+  //...
+  DNS_FOUND,
+};
+
+class NetDnsRequest;
+enum NetDnsReply;
+
+///This is a simple DNS Request class
+/**
+  This class exposes an API to deal with DNS Requests
+*/
+class DNSRequest
+{
+public:
+  ///Creates a new request
+  DNSRequest();
+  
+  ///Terminates and closes request
+  ~DNSRequest();
+  
+  ///Resolves an hostname
+  /**
+  @param hostname : hostname to resolve
+  */
+  DNSRequestErr resolve(const char* hostname);
+  
+  ///Resolves an hostname
+  /**
+  @param host : hostname to resolve, the result will be stored in the IpAddr field of this object
+  */
+  DNSRequestErr resolve(Host* pHost);
+  
+  ///Setups callback
+  /**
+  The callback function will be called on result.
+  @param pMethod : callback function
+  */  
+  void setOnReply( void (*pMethod)(DNSReply) );
+  
+  class CDummy;
+  ///Setups callback
+  /**
+  The callback function will be called on result.
+  @param pItem : instance of class on which to execute the callback method
+  @param pMethod : callback method
+  */
+  template<class T> 
+  void setOnReply( T* pItem, void (T::*pMethod)(DNSReply) )
+  {
+    m_pCbItem = (CDummy*) pItem;
+    m_pCbMeth = (void (CDummy::*)(DNSReply)) pMethod;
+  }
+  
+  ///Gets IP address once it has been resolved
+  /**
+  @param pIp : pointer to an IpAddr instance in which to store the resolved IP address
+  */
+  DNSRequestErr getResult(IpAddr* pIp);
+  
+  ///Closes DNS Request before completion
+  DNSRequestErr close();
+  
+protected:
+  void onNetDnsReply(NetDnsReply r);
+  DNSRequestErr checkInst();
+
+private:
+  NetDnsRequest* m_pNetDnsRequest;
+  
+  CDummy* m_pCbItem;
+  void (CDummy::*m_pCbMeth)(DNSReply);
+  
+  void (*m_pCb)(DNSReply);
+
+};
+
+#endif
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/api/TCPSocket.cpp	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,147 @@
+
+/*
+Copyright (c) 2010 Donatien Garnier (donatiengar [at] gmail [dot] com)
+ 
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+ 
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+ 
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+#include "TCPSocket.h"
+#include "if/net/nettcpsocket.h"
+
+TCPSocket::TCPSocket() : m_pNetTcpSocket(NULL), m_pCbItem(NULL), m_pCbMeth(NULL), m_pCb(NULL)
+{
+
+}
+
+TCPSocket::TCPSocket(NetTcpSocket* pNetTcpSocket) : m_pNetTcpSocket(pNetTcpSocket), m_pCbItem(NULL), m_pCbMeth(NULL), m_pCb(NULL)
+{
+  m_pNetTcpSocket->setOnEvent(this, &TCPSocket::onNetTcpSocketEvent);
+}
+
+TCPSocket::~TCPSocket() //close()
+{
+  close();
+}
+  
+TCPSocketErr TCPSocket::bind(const Host& me)
+{
+  TCPSocketErr tcpSocketErr = checkInst();
+  if(tcpSocketErr)
+    return tcpSocketErr;
+  return (TCPSocketErr) m_pNetTcpSocket->bind(me); 
+}
+
+TCPSocketErr TCPSocket::listen()
+{
+  TCPSocketErr tcpSocketErr = checkInst();
+  if(tcpSocketErr)
+    return tcpSocketErr;
+  return (TCPSocketErr) m_pNetTcpSocket->listen(); 
+}
+
+TCPSocketErr TCPSocket::connect(const Host& host)
+{
+  TCPSocketErr tcpSocketErr = checkInst();
+  if(tcpSocketErr)
+    return tcpSocketErr;
+  return (TCPSocketErr) m_pNetTcpSocket->connect(host); 
+}
+
+TCPSocketErr TCPSocket::accept(Host* pClient, TCPSocket** ppNewTCPSocket)
+{
+  TCPSocketErr tcpSocketErr = checkInst();
+  if(tcpSocketErr)
+    return tcpSocketErr;
+  NetTcpSocket* pNewNetTcpSocket;
+  tcpSocketErr = (TCPSocketErr) m_pNetTcpSocket->accept(pClient, &pNewNetTcpSocket);
+  if(pNewNetTcpSocket)
+    *ppNewTCPSocket = new TCPSocket(pNewNetTcpSocket);
+  return tcpSocketErr;
+}
+  
+int /*if < 0 : TCPSocketErr*/ TCPSocket::send(const char* buf, int len)
+{
+  TCPSocketErr tcpSocketErr = checkInst();
+  if(tcpSocketErr)
+    return tcpSocketErr;
+  return m_pNetTcpSocket->send(buf, len);  
+}
+
+int /*if < 0 : TCPSocketErr*/ TCPSocket::recv(char* buf, int len)
+{
+  TCPSocketErr tcpSocketErr = checkInst();
+  if(tcpSocketErr)
+    return tcpSocketErr;
+  return m_pNetTcpSocket->recv(buf, len);
+}
+
+TCPSocketErr TCPSocket::close()
+{
+  if(!m_pNetTcpSocket)
+    return TCPSOCKET_SETUP;
+  m_pNetTcpSocket->resetOnEvent();
+  TCPSocketErr tcpSocketErr = (TCPSocketErr) m_pNetTcpSocket->close(); //Close (can already be closed)
+  Net::releaseTcpSocket(m_pNetTcpSocket); //And release it so it can be freed when properly removed
+  m_pNetTcpSocket = NULL;
+  return tcpSocketErr;
+}
+
+//Callbacks
+void TCPSocket::setOnEvent( void (*pMethod)(TCPSocketEvent) )
+{
+  m_pCb = pMethod;
+}
+
+#if 0 //For info only
+template<class T> 
+void TCPSocket::setOnEvent( T* pItem, void (T::*pMethod)(TCPSocketEvent) )
+{
+  m_pCbItem = (CDummy*) pItem;
+  m_pCbMeth = (void (CDummy::*)(TCPSocketEvent)) pMethod;
+}
+#endif
+  
+void TCPSocket::resetOnEvent() //Disable callback
+{
+  m_pCb = NULL;
+  m_pCbItem = NULL;
+  m_pCbMeth = NULL;
+}
+
+void TCPSocket::onNetTcpSocketEvent(NetTcpSocketEvent e)
+{
+  if(m_pCbItem && m_pCbMeth)
+    (m_pCbItem->*m_pCbMeth)((TCPSocketEvent) e);
+  else if(m_pCb)
+    m_pCb((TCPSocketEvent) e);
+}
+
+TCPSocketErr TCPSocket::checkInst()
+{
+  if(!m_pNetTcpSocket)
+  {
+    m_pNetTcpSocket = Net::tcpSocket();
+    if(!m_pNetTcpSocket)
+    {
+      return TCPSOCKET_IF; //Interface did not return a socket (usually because a default interface does not exist)
+    }
+    m_pNetTcpSocket->setOnEvent(this, &TCPSocket::onNetTcpSocketEvent);
+  }
+  return TCPSOCKET_OK;
+}
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/api/TCPSocket.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,148 @@
+
+/*
+Copyright (c) 2010 Donatien Garnier (donatiengar [at] gmail [dot] com)
+ 
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+ 
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+ 
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+/** \file
+TCP Socket header file
+*/
+
+#ifndef TCPSOCKET_H
+#define TCPSOCKET_H
+
+#include "core/net.h"
+#include "core/host.h"
+//Essentially it is a safe interface to NetTcpSocket
+
+///TCP Socket error codes
+enum TCPSocketErr
+{
+  __TCPSOCKET_MIN = -0xFFFF,
+  TCPSOCKET_SETUP, ///<TCPSocket not properly configured
+  TCPSOCKET_TIMEOUT, ///<Connection timed out
+  TCPSOCKET_IF, ///<Interface has problems, does not exist or is not initialized
+  TCPSOCKET_MEM, ///<Not enough mem
+  TCPSOCKET_INUSE, ///<Interface / Port is in use
+  TCPSOCKET_EMPTY, ///<Connections queue is empty
+  TCPSOCKET_RST, ///<Connection was reset by remote host
+//...
+  TCPSOCKET_OK = 0 ///<Success
+};
+
+///TCP Socket Events
+enum TCPSocketEvent
+{
+  TCPSOCKET_CONNECTED, ///<Connected to host
+  TCPSOCKET_ACCEPT,  ///<Client is connected, must call accept() to get a new Socket
+  TCPSOCKET_READABLE, ///<Data in buf
+  TCPSOCKET_WRITEABLE, ///<Can write data to buf
+  TCPSOCKET_CONTIMEOUT, ///<Connection timed out
+  TCPSOCKET_CONRST, ///<Connection was reset by remote host
+  TCPSOCKET_CONABRT, ///<Connection was aborted
+  TCPSOCKET_ERROR, ///<Unknown error
+  TCPSOCKET_DISCONNECTED ///<Disconnected
+};
+
+class NetTcpSocket;
+enum NetTcpSocketEvent;
+
+///This is a simple TCP Socket class
+/**
+  This class exposes an API to deal with TCP Sockets
+*/
+class TCPSocket
+{
+public:
+  ///Creates a new socket
+  TCPSocket();
+protected:
+  TCPSocket(NetTcpSocket* pNetTcpSocket);
+public:
+  ///Closes if needed and destroys the socket
+  ~TCPSocket(); //close()
+  
+  ///Binds the socket to (local) host
+  TCPSocketErr bind(const Host& me);
+  
+  ///Starts listening
+  TCPSocketErr listen();
+  
+  ///Connects socket to host
+  TCPSocketErr connect(const Host& host);
+  
+  ///Accepts connection from client and gets connected socket
+  TCPSocketErr accept(Host* pClient, TCPSocket** ppNewTcpSocket);
+  
+  ///Sends data
+  /*
+  @return a negative error code or the number of bytes transmitted
+  */
+  int /*if < 0 : TCPSocketErr*/ send(const char* buf, int len);
+  
+  ///Receives data
+  /*
+  @return a negative error code or the number of bytes received
+  */
+  int /*if < 0 : TCPSocketErr*/ recv(char* buf, int len);
+
+  /* TODO NTH : printf / scanf helpers that call send/recv */
+
+  ///Closes socket
+  TCPSocketErr close();
+
+  //Callbacks
+  ///Setups callback
+  /**
+  @param pMethod : callback function
+  */
+  void setOnEvent( void (*pMethod)(TCPSocketEvent) );
+  
+  class CDummy;
+  ///Setups callback
+  /**
+  @param pItem : instance of class on which to execute the callback method
+  @param pMethod : callback method
+  */
+  template<class T> 
+  void setOnEvent( T* pItem, void (T::*pMethod)(TCPSocketEvent) )
+  {
+    m_pCbItem = (CDummy*) pItem;
+    m_pCbMeth = (void (CDummy::*)(TCPSocketEvent)) pMethod;
+  }
+  
+  ///Disables callback
+  void resetOnEvent(); 
+  
+protected:
+  void onNetTcpSocketEvent(NetTcpSocketEvent e);
+  TCPSocketErr checkInst();
+
+private:
+  NetTcpSocket* m_pNetTcpSocket;
+  
+  CDummy* m_pCbItem;
+  void (CDummy::*m_pCbMeth)(TCPSocketEvent);
+  
+  void (*m_pCb)(TCPSocketEvent);
+  
+};
+
+#endif
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/api/UDPSocket.cpp	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,114 @@
+
+/*
+Copyright (c) 2010 Donatien Garnier (donatiengar [at] gmail [dot] com)
+ 
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+ 
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+ 
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+#include "UDPSocket.h"
+#include "if/net/netudpsocket.h"
+
+UDPSocket::UDPSocket() : m_pNetUdpSocket(NULL), m_pCbItem(NULL), m_pCbMeth(NULL), m_pCb(NULL)
+{
+
+}
+
+UDPSocket::~UDPSocket() //close()
+{
+  close();
+}
+  
+UDPSocketErr UDPSocket::bind(const Host& me)
+{
+  UDPSocketErr udpSocketErr = checkInst();
+  if(udpSocketErr)
+    return udpSocketErr;
+  return (UDPSocketErr) m_pNetUdpSocket->bind(me); 
+}
+  
+int /*if < 0 : UDPSocketErr*/ UDPSocket::sendto(const char* buf, int len, Host* pHost)
+{
+  UDPSocketErr udpSocketErr = checkInst();
+  if(udpSocketErr)
+    return udpSocketErr;
+  return m_pNetUdpSocket->sendto(buf, len, pHost);  
+}
+
+int /*if < 0 : UDPSocketErr*/ UDPSocket::recvfrom(char* buf, int len, Host* pHost)
+{
+  UDPSocketErr udpSocketErr = checkInst();
+  if(udpSocketErr)
+    return udpSocketErr;
+  return m_pNetUdpSocket->recvfrom(buf, len, pHost);
+}
+
+UDPSocketErr UDPSocket::close()
+{
+  if(!m_pNetUdpSocket)
+    return UDPSOCKET_SETUP;
+  m_pNetUdpSocket->resetOnEvent();
+  UDPSocketErr udpSocketErr = (UDPSocketErr) m_pNetUdpSocket->close(); //Close (can already be closed)
+  Net::releaseUdpSocket(m_pNetUdpSocket); //And release it so it can be freed when properly removed
+  m_pNetUdpSocket = NULL;
+  return udpSocketErr;
+}
+
+//Callbacks
+void UDPSocket::setOnEvent( void (*pMethod)(UDPSocketEvent) )
+{
+  m_pCb = pMethod;
+}
+
+#if 0 //For info only
+template<class T> 
+void UDPSocket::setOnEvent( T* pItem, void (T::*pMethod)(UDPSocketEvent) )
+{
+  m_pCbItem = (CDummy*) pItem;
+  m_pCbMeth = (void (CDummy::*)(UDPSocketEvent)) pMethod;
+}
+#endif
+  
+void UDPSocket::resetOnEvent() //Disable callback
+{
+  m_pCb = NULL;
+  m_pCbItem = NULL;
+  m_pCbMeth = NULL;
+}
+
+void UDPSocket::onNetUdpSocketEvent(NetUdpSocketEvent e)
+{
+  if(m_pCbItem && m_pCbMeth)
+    (m_pCbItem->*m_pCbMeth)((UDPSocketEvent) e);
+  else if(m_pCb)
+    m_pCb((UDPSocketEvent) e);
+}
+
+UDPSocketErr UDPSocket::checkInst()
+{
+  if(!m_pNetUdpSocket)
+  {
+    m_pNetUdpSocket = Net::udpSocket();
+    if(!m_pNetUdpSocket)
+    {
+      return UDPSOCKET_IF; //Interface did not return a socket (usually because a default interface does not exist)
+    }
+    m_pNetUdpSocket->setOnEvent(this, &UDPSocket::onNetUdpSocketEvent);
+  }
+  return UDPSOCKET_OK;
+}
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/api/UDPSocket.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,128 @@
+
+/*
+Copyright (c) 2010 Donatien Garnier (donatiengar [at] gmail [dot] com)
+ 
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+ 
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+ 
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+/** \file
+UDP Socket header file
+*/
+
+#ifndef UDPSOCKET_H
+#define UDPSOCKET_H
+
+#include "core/net.h"
+#include "core/host.h"
+//Essentially it is a safe interface to NetUdpSocket
+
+///UDP Socket error codes
+enum UDPSocketErr
+{
+  __UDPSOCKET_MIN = -0xFFFF,
+  UDPSOCKET_SETUP, ///<UDPSocket not properly configured
+  UDPSOCKET_IF, ///<Interface has problems, does not exist or is not initialized
+  UDPSOCKET_MEM, ///<Not enough mem
+  UDPSOCKET_INUSE, ///<Interface / Port is in use
+//...
+  UDPSOCKET_OK = 0 ///<Success
+};
+
+///UDP Socket Event(s)
+enum UDPSocketEvent //Only one event here for now, but keeps that model in case we need to implement some others
+{
+  UDPSOCKET_READABLE, ///<Data in buf
+};
+
+class NetUdpSocket;
+enum NetUdpSocketEvent;
+
+///This is a simple UDP Socket class
+/**
+  This class exposes an API to deal with UDP Sockets
+*/
+class UDPSocket
+{
+public:
+  ///Creates a new socket
+  UDPSocket();
+  
+  ///Closes and destroys socket
+  ~UDPSocket(); //close()
+  
+  ///Binds the socket to local host or a multicast address
+  UDPSocketErr bind(const Host& me);
+  
+  ///Sends data
+  /*
+  @param pHost : host to send data to
+  @return a negative error code or the number of bytes transmitted
+  */
+  int /*if < 0 : UDPSocketErr*/ sendto(const char* buf, int len, Host* pHost);
+  
+  ///Receives data
+  /*
+  @param pHost : host from which this piece of data comes from
+  @return a negative error code or the number of bytes received
+  */
+  int /*if < 0 : UDPSocketErr*/ recvfrom(char* buf, int len, Host* pHost);
+
+  /* TODO NTH : printf / scanf helpers that call send/recv */
+
+  ///Closes socket
+  UDPSocketErr close();
+
+  //Callbacks
+  ///Setups callback
+  /**
+  @param pMethod : callback function
+  */  
+  void setOnEvent( void (*pMethod)(UDPSocketEvent) );
+  
+  class CDummy;
+  ///Setups callback
+  /**
+  @param pItem : instance of class on which to execute the callback method
+  @param pMethod : callback method
+  */
+  template<class T> 
+  void setOnEvent( T* pItem, void (T::*pMethod)(UDPSocketEvent) )
+  {
+    m_pCbItem = (CDummy*) pItem;
+    m_pCbMeth = (void (CDummy::*)(UDPSocketEvent)) pMethod;
+  }
+  
+  ///Disables callback
+  void resetOnEvent();
+
+protected:
+  void onNetUdpSocketEvent(NetUdpSocketEvent e);
+  UDPSocketErr checkInst();
+
+private:
+  NetUdpSocket* m_pNetUdpSocket;
+  
+  CDummy* m_pCbItem;
+  void (CDummy::*m_pCbMeth)(UDPSocketEvent);
+  
+  void (*m_pCb)(UDPSocketEvent);
+
+};
+
+#endif
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/core/host.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,109 @@
+
+/*
+Copyright (c) 2010 Donatien Garnier (donatiengar [at] gmail [dot] com)
+ 
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+ 
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+ 
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+#ifndef HOST_H
+#define HOST_H
+
+#include "ipaddr.h"
+#include <string.h>
+
+///Host information container
+/**
+This class is a container for data relative to a connection:
+- IP Address
+- Port number
+- Host Name
+*/
+class Host 
+{
+public:
+  ///Initiliazes host with null values
+  Host() : m_ip(0,0,0,0), m_port(0), m_name(NULL)
+  {
+    
+  }
+  
+  ///Initializes host
+  Host(const IpAddr& ip, const int& port, const char* name="" ) : m_ip(ip), m_port(port), m_name(NULL)
+  {
+    setName(name); 
+  }
+  
+  ~Host()
+  {
+    if(m_name)
+    {
+      delete[] m_name;
+    }
+  }
+  
+  ///Returns IP address
+  const IpAddr& getIp() const
+  {
+    return m_ip;
+  }
+  
+  ///Returns port number
+  const int& getPort() const
+  {
+    return m_port;
+  }
+  
+  ///Returns host name
+  const char* getName() const
+  {
+    return m_name;
+  }
+  
+  ///Sets IP address
+  void setIp(const IpAddr& ip)
+  {
+    m_ip = ip;
+  }
+  
+  ///Sets port number
+  void setPort(int port)
+  {
+    m_port = port;
+  }
+  
+  ///Sets host name
+  void setName(const char* name)
+  {
+    if(m_name)
+      delete[] m_name;
+    int len = strlen(name);
+    if(len)
+    {
+      m_name = new char[len+1];
+      strcpy(m_name, name);
+    }
+  }
+  
+private:
+  IpAddr m_ip;
+  int m_port;
+  char* m_name;
+};
+
+#endif
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/core/ipaddr.cpp	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,104 @@
+
+/*
+Copyright (c) 2010 Donatien Garnier (donatiengar [at] gmail [dot] com)
+ 
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+ 
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+ 
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+#include "ipaddr.h"
+
+#include "netCfg.h"
+#if NET_LWIP_STACK
+#include "lwip/ip_addr.h"
+#endif
+
+
+#if NET_LWIP_STACK
+IpAddr::IpAddr(ip_addr_t* pIp)
+{
+  *((uint32_t*)m_ip) = pIp->addr;
+}
+#endif
+
+///Initializes IP address with provided values
+IpAddr::IpAddr(uint8_t ip0, uint8_t ip1, uint8_t ip2, uint8_t ip3)
+{
+  //We are in LE
+  m_ip[0] = ip0;
+  m_ip[1] = ip1;
+  m_ip[2] = ip2;
+  m_ip[3] = ip3;
+}
+
+///Initializes IP address with null values 
+IpAddr::IpAddr()
+{
+  m_ip[0] = 0;
+  m_ip[1] = 0;
+  m_ip[2] = 0;
+  m_ip[3] = 0;
+}
+
+
+#if NET_LWIP_STACK
+ip_addr_t IpAddr::getStruct() const
+{
+  ip_addr_t ip_struct;
+  ip_struct.addr = *((uint32_t*)m_ip);
+  return ip_struct;
+}
+#endif
+
+uint8_t IpAddr::operator[](unsigned int i) const
+{
+  uint8_t null = 0;
+  if( i > 3 )
+    return null;
+  return m_ip[i];
+}
+
+bool IpAddr::isEq(const IpAddr& b) const
+{
+  return (*((uint32_t*)m_ip) == *((uint32_t*)(b.m_ip)));
+}
+
+bool IpAddr::operator==(const IpAddr& b) const
+{
+  return isEq(b);
+}
+ 
+bool IpAddr::operator!=(const IpAddr& b) const
+{
+  return !(operator==(b));
+}
+
+bool IpAddr::isNull() const
+{
+  return (*((uint32_t*)m_ip) == 0);
+}
+
+bool IpAddr::isBroadcast() const
+{
+  return (*((uint32_t*)m_ip) == 0xFFFFFFFF);
+}
+
+bool IpAddr::isMulticast() const
+{
+  return ((m_ip[0] & 0xF0) == 0xE0);
+}
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/core/ipaddr.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,98 @@
+
+/*
+Copyright (c) 2010 Donatien Garnier (donatiengar [at] gmail [dot] com)
+ 
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+ 
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+ 
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+#ifndef IPADDR_H
+#define IPADDR_H
+
+#include "netCfg.h"
+#if NET_LWIP_STACK
+typedef struct ip_addr ip_addr_t;
+#endif
+
+#include "stdint.h"
+
+///IP Address container
+/**
+This class is a container for an IPv4 address.
+*/
+class IpAddr //Basically a C++ frontend to ip_addr_t
+{
+public:
+  #if NET_LWIP_STACK
+  IpAddr(ip_addr_t* pIp);
+  #endif
+  
+  ///Initializes IP address with provided values
+  IpAddr(uint8_t ip0, uint8_t ip1, uint8_t ip2, uint8_t ip3);
+  
+  ///Initializes IP address with null values 
+  IpAddr();
+
+  #if NET_LWIP_STACK
+  ip_addr_t getStruct() const;
+  #endif
+  
+  ///Returns IP address byte #
+  uint8_t operator[](unsigned int i) const;
+  
+  ///Compares too addresses
+  /**
+  @return true if the two addresses are equal
+  */
+  bool isEq(const IpAddr& b) const;
+  
+  ///Compares too addresses
+  /**
+  @return true if the two addresses are equal
+  */
+  bool operator==(const IpAddr& b) const;
+ 
+  ///Compares too addresses
+  /**
+  @return true if the two addresses are different
+  */ 
+  bool operator!=(const IpAddr& b) const;
+  
+  ///Checks whether the address is null
+  /**
+  @return true if the address is null
+  */
+  bool isNull() const;
+  
+  ///Checks whether the address is a broadcast address
+  /**
+  @return true if the address is a broadcast address
+  */
+  bool isBroadcast() const;
+
+  ///Checks whether the address is a multicast address
+  /**
+  @return true if the address is a multicast address
+  */
+  bool isMulticast() const;
+  
+private:
+  uint8_t m_ip[4];
+};
+
+#endif
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/core/net.cpp	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,229 @@
+
+/*
+Copyright (c) 2010 Donatien Garnier (donatiengar [at] gmail [dot] com)
+ 
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+ 
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+ 
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+#include "net.h"
+
+#include "host.h"
+#include "ipaddr.h"
+#include "netservice.h"
+#include "if/net/netif.h"
+#include "if/net/nettcpsocket.h"
+#include "if/net/netudpsocket.h"
+#include "if/net/netdnsrequest.h"
+
+//#define __DEBUG
+#include "dbg/dbg.h"
+
+Net::Net() : m_defaultIf(NULL), m_lpIf(), m_lpNetTcpSocket(), m_lpNetUdpSocket()
+{
+
+}
+
+Net::~Net()
+{
+
+}
+
+
+void Net::poll()
+{
+  //DBG("\r\nNet : Services polling\r\n");
+
+  //Poll Services
+  NetService::servicesPoll();  
+  
+  //DBG("\r\nNet : Interfaces polling\r\n");   
+      
+  //Poll Interfaces
+  list<NetIf*>::iterator pIfIt;
+
+  for ( pIfIt = net().m_lpIf.begin() ; pIfIt != net().m_lpIf.end(); pIfIt++ )
+  {
+    (*pIfIt)->poll();
+  }
+  
+  //DBG("\r\nNet : Sockets polling\r\n");
+  
+  //Poll Tcp Sockets
+  list<NetTcpSocket*>::iterator pNetTcpSocketIt;
+
+  for ( pNetTcpSocketIt = net().m_lpNetTcpSocket.begin() ; pNetTcpSocketIt != net().m_lpNetTcpSocket.end(); )
+  {
+    (*pNetTcpSocketIt)->poll();
+    
+    if( (*pNetTcpSocketIt)->m_closed && !((*pNetTcpSocketIt)->m_refs) )
+    {
+      (*pNetTcpSocketIt)->m_removed = true;
+      delete (*pNetTcpSocketIt);
+      (*pNetTcpSocketIt) = NULL;
+      pNetTcpSocketIt = net().m_lpNetTcpSocket.erase(pNetTcpSocketIt);
+    }
+    else
+    {
+      pNetTcpSocketIt++;
+    }
+  }
+  
+  //Poll Udp Sockets
+  list<NetUdpSocket*>::iterator pNetUdpSocketIt;
+
+  for ( pNetUdpSocketIt = net().m_lpNetUdpSocket.begin() ; pNetUdpSocketIt != net().m_lpNetUdpSocket.end(); )
+  {
+    (*pNetUdpSocketIt)->poll();
+    
+    if( (*pNetUdpSocketIt)->m_closed && !((*pNetUdpSocketIt)->m_refs) )
+    {
+      (*pNetUdpSocketIt)->m_removed = true;
+      delete (*pNetUdpSocketIt);
+      (*pNetUdpSocketIt) = NULL;
+      pNetUdpSocketIt = net().m_lpNetUdpSocket.erase(pNetUdpSocketIt);
+    }
+    else
+    {
+      pNetUdpSocketIt++;
+    }
+  }
+
+
+}
+
+NetTcpSocket* Net::tcpSocket(NetIf& netif) {
+  NetTcpSocket* pNetTcpSocket = netif.tcpSocket();
+  pNetTcpSocket->m_refs++;
+  return pNetTcpSocket; 
+}
+
+NetTcpSocket* Net::tcpSocket() { //NetTcpSocket on default if
+ if ( net().m_defaultIf == NULL )
+      return NULL;
+  NetTcpSocket* pNetTcpSocket = net().m_defaultIf->tcpSocket();
+  pNetTcpSocket->m_refs++;
+  return pNetTcpSocket;
+}
+
+void Net::releaseTcpSocket(NetTcpSocket* pNetTcpSocket)
+{
+  pNetTcpSocket->m_refs--;
+  if(!pNetTcpSocket->m_closed && !pNetTcpSocket->m_refs)
+    pNetTcpSocket->close();
+}
+
+NetUdpSocket* Net::udpSocket(NetIf& netif) {
+  NetUdpSocket* pNetUdpSocket = netif.udpSocket();
+  pNetUdpSocket->m_refs++;
+  return pNetUdpSocket; 
+}
+
+NetUdpSocket* Net::udpSocket() { //NetTcpSocket on default if
+ if ( net().m_defaultIf == NULL )
+      return NULL;
+  NetUdpSocket* pNetUdpSocket = net().m_defaultIf->udpSocket();
+  pNetUdpSocket->m_refs++;
+  return pNetUdpSocket;
+}
+
+void Net::releaseUdpSocket(NetUdpSocket* pNetUdpSocket)
+{
+  pNetUdpSocket->m_refs--;
+  if(!pNetUdpSocket->m_closed && !pNetUdpSocket->m_refs)
+    pNetUdpSocket->close();
+}
+
+NetDnsRequest* Net::dnsRequest(const char* hostname, NetIf& netif) {
+  return netif.dnsRequest(hostname);
+}
+
+NetDnsRequest* Net::dnsRequest(const char* hostname) { //Create a new NetDnsRequest object from default if
+  if ( net().m_defaultIf == NULL )
+      return NULL;
+  return net().m_defaultIf->dnsRequest(hostname);
+}
+
+NetDnsRequest* Net::dnsRequest(Host* pHost, NetIf& netif)
+{
+  return netif.dnsRequest(pHost);
+}
+
+NetDnsRequest* Net::dnsRequest(Host* pHost) //Creats a new NetDnsRequest object from default if
+{
+  if ( net().m_defaultIf == NULL )
+      return NULL;
+  return net().m_defaultIf->dnsRequest(pHost);
+}
+
+void Net::setDefaultIf(NetIf& netif) {
+  net().m_defaultIf = &netif;
+}
+
+void Net::setDefaultIf(NetIf* pIf)
+{
+  net().m_defaultIf = pIf;
+}
+
+NetIf* Net::getDefaultIf() {
+  return net().m_defaultIf;
+}
+
+void Net::registerIf(NetIf* pIf)
+{
+  net().m_lpIf.push_back(pIf);
+}
+
+void Net::unregisterIf(NetIf* pIf)
+{
+  if( net().m_defaultIf == pIf )
+    net().m_defaultIf = NULL;
+  net().m_lpIf.remove(pIf);
+}
+
+void Net::registerNetTcpSocket(NetTcpSocket* pNetTcpSocket)
+{
+  net().m_lpNetTcpSocket.push_back(pNetTcpSocket);
+  DBG("\r\nNetTcpSocket [ + %p ] %d\r\n", (void*)pNetTcpSocket, net().m_lpNetTcpSocket.size());
+}
+
+void Net::unregisterNetTcpSocket(NetTcpSocket* pNetTcpSocket)
+{
+  DBG("\r\nNetTcpSocket [ - %p ] %d\r\n", (void*)pNetTcpSocket, net().m_lpNetTcpSocket.size() - 1);
+  if(!pNetTcpSocket->m_removed)
+    net().m_lpNetTcpSocket.remove(pNetTcpSocket);
+}
+
+void Net::registerNetUdpSocket(NetUdpSocket* pNetUdpSocket)
+{
+  net().m_lpNetUdpSocket.push_back(pNetUdpSocket);
+  DBG("\r\nNetUdpSocket [ + %p ] %d\r\n", (void*)pNetUdpSocket, net().m_lpNetUdpSocket.size());
+}
+
+void Net::unregisterNetUdpSocket(NetUdpSocket* pNetUdpSocket)
+{
+  DBG("\r\nNetUdpSocket [ - %p ] %d\r\n", (void*)pNetUdpSocket, net().m_lpNetUdpSocket.size() - 1);
+  if(!pNetUdpSocket->m_removed)
+    net().m_lpNetUdpSocket.remove(pNetUdpSocket);
+}
+
+Net& Net::net()
+{
+  static Net* pInst = new Net(); //Called only once
+  return *pInst;
+}
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/core/net.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,101 @@
+
+/*
+Copyright (c) 2010 Donatien Garnier (donatiengar [at] gmail [dot] com)
+ 
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+ 
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+ 
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+#ifndef NET_H
+#define NET_H
+
+class NetIf;
+class NetTcpSocket;
+class NetUdpSocket;
+class NetDnsRequest;
+
+#include <list>
+using std::list;
+
+/*
+#include "host.h"
+#include "ipaddr.h"
+#include "netservice.h"
+#include "if/net/netif.h"
+#include "if/net/nettcpsocket.h"
+#include "if/net/netudpsocket.h"
+#include "if/net/netdnsrequest.h"
+*/
+
+class Host;
+class NetIf;
+class NetTcpSocket;
+class NetUdpSocket;
+class NetDnsRequest;
+
+class Net
+{
+private:
+  Net();
+  ~Net();
+public:  
+  static void poll(); //Poll every if & socket
+  
+  static NetTcpSocket* tcpSocket(NetIf& netif);
+  static NetTcpSocket* tcpSocket(); //Socket on default if
+  static void releaseTcpSocket(NetTcpSocket* pNetTcpSocket);
+  
+  static NetUdpSocket* udpSocket(NetIf& netif);
+  static NetUdpSocket* udpSocket(); //Socket on default if
+  static void releaseUdpSocket(NetUdpSocket* pNetUdpSocket);
+  
+  static NetDnsRequest* dnsRequest(const char* hostname, NetIf& netif);
+  static NetDnsRequest* dnsRequest(const char* hostname); //Create a new NetDnsRequest object from default if
+
+  static NetDnsRequest* dnsRequest(Host* pHost, NetIf& netif);
+  static NetDnsRequest* dnsRequest(Host* pHost); //Create a new NetDnsRequest object from default if
+  
+  static void setDefaultIf(NetIf& netif); //Deprecated
+  static void setDefaultIf(NetIf* pIf);
+  static NetIf* getDefaultIf();
+  
+protected:
+  friend class NetIf;
+  friend class NetTcpSocket;
+  friend class NetUdpSocket;
+  
+  static void registerIf(NetIf* pIf);
+  static void unregisterIf(NetIf* pIf);
+  
+  static void registerNetTcpSocket(NetTcpSocket* pNetTcpSocket);
+  static void unregisterNetTcpSocket(NetTcpSocket* pNetTcpSocket);  
+  
+  static void registerNetUdpSocket(NetUdpSocket* pNetUdpSocket);
+  static void unregisterNetUdpSocket(NetUdpSocket* pNetUdpSocket);  
+  
+private:
+  static Net& net(); //Return inst of singleton
+
+  NetIf* m_defaultIf;
+  
+  list<NetIf*> m_lpIf;
+  list<NetTcpSocket*> m_lpNetTcpSocket;
+  list<NetUdpSocket*> m_lpNetUdpSocket;
+};
+
+#endif
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/core/netservice.cpp	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,88 @@
+
+/*
+Copyright (c) 2010 Donatien Garnier (donatiengar [at] gmail [dot] com)
+ 
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+ 
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+ 
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+#include "netservice.h"
+#include "net.h"
+
+//#define __DEBUG
+#include "dbg/dbg.h"
+
+NetService::NetService(bool owned /*= true*/) : m_closed(false), m_removed(false), m_owned(owned)
+{
+  NetService::lpServices().push_back(this);
+  DBG("\r\n[ + %p ] %d\r\n", (void*)this, lpServices().size());
+}
+
+NetService::~NetService()
+{
+ // DBG("\r\nService removed\r\n");
+//  DBG("\r\nNow %d services running\r\n", lpServices().size()-1);
+  DBG("\r\n[ - %p ] %d\r\n", (void*)this, lpServices().size()-1);
+  if((!m_owned) || (!m_removed)) //Destructor was not called by servicesPoll()
+  { 
+    if(m_owned)
+      DBG("\r\nWARN!!!Service removed in dtor!!!\r\n");
+    NetService::lpServices().remove(this);
+  }
+}
+
+void NetService::poll()
+{
+
+}
+  
+void NetService::servicesPoll() //Poll all registered services & destroy closed ones
+{
+  list<NetService*>::iterator it;
+  DBG("\r\nServices polling over %d services\r\n", lpServices().size());
+  for( it = lpServices().begin(); it != lpServices().end();  )
+  {
+    if( (*it)->m_owned && (*it)->m_closed  )
+    {
+      DBG("\r\nService %p is flagged as closed\r\n", (*it));
+      (*it)->m_removed = true;
+      delete (*it);
+      it = lpServices().erase(it);
+    }
+    else
+    {
+      //DBG("Service %p polling start\n", (*it));
+      (*it)->poll();
+      //DBG("Service %p polling end\n", (*it));
+      it++;
+    }
+  }
+  
+}
+
+void NetService::close()
+{
+  DBG("\r\nService %p to be closed (owned = %d)\r\n", this, m_owned);
+  m_closed = true;
+}
+
+list<NetService*>& NetService::lpServices()
+{
+  static list<NetService*>* pInst = new list<NetService*>(); //Called only once
+  return *pInst;
+}
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/core/netservice.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,67 @@
+
+/*
+Copyright (c) 2010 Donatien Garnier (donatiengar [at] gmail [dot] com)
+ 
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+ 
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+ 
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+/**
+\file Net Service base class header file
+*/
+
+#ifndef NETSERVICE_H
+#define NETSERVICE_H
+
+#include <list>
+using std::list;
+
+///Net Service base class
+/**
+Each connection-oriented object can register as service (by inheriting this class), so that it is polled regularly.
+It notifies the pool when the connection is terminated so that it can be destroyed.
+*/
+class NetService
+{
+public:
+  ///Instantiates a new service
+  /**
+  @param owned If true the object is owned by the pool and will be destroyed on closure.
+  */
+  NetService(bool owned = true); //Is owned by the pool?
+  virtual ~NetService();
+
+  ///This method can be inherited so that it is called on each @a Net::poll() call.
+  virtual void poll();
+ 
+  static void servicesPoll(); //Poll all registered services & destroy closed ones
+
+protected:
+  ///This flags the service as to be destructed if owned by the pool.
+  void close();
+  
+private:
+  bool m_closed;
+  bool m_removed;
+  bool m_owned;
+  
+  static list<NetService*>& lpServices(); //Helper to prevent static initialization fiasco  
+
+};
+
+#endif
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/dbg/dbg.cpp	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,63 @@
+
+/*
+Copyright (c) 2010 Donatien Garnier (donatiengar [at] gmail [dot] com)
+ 
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+ 
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+ 
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+#define __LWIP_DEBUG
+#define __DEBUG
+#include "dbg.h"
+#include "mbed.h"
+#include <cstdarg>
+
+void DebugStream::debug(const char* format, ...)
+{ 
+  va_list argp;
+  
+  va_start(argp, format);
+  vprintf(format, argp);
+  va_end(argp);
+}
+
+void DebugStream::release()
+{
+
+}
+
+void DebugStream::breakPoint(const char* file, int line)
+{
+  printf("\r\nBREAK in %s at line %d\r\n", file, line);
+  fflush(stdout);
+  getchar();
+  fflush(stdin);
+}
+
+/*
+int snprintf(char *str, int size, const char *format, ...)
+{
+  va_list argp;
+  
+  va_start(argp, format);
+  vsprintf(str, format, argp);
+  va_end(argp);
+  
+  return strlen(str);
+}
+*/
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/dbg/dbg.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,94 @@
+
+/*
+Copyright (c) 2010 Donatien Garnier (donatiengar [at] gmail [dot] com)
+ 
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+ 
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+ 
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+/** \file
+Debugging helpers header file
+*/
+
+//#ifdef DBG_H
+//#define DBG_H
+
+#ifdef __LWIP_DEBUG
+#define __DEBUG
+#endif
+
+/*!
+  \def __DEBUG
+  To define to enable debugging in one file
+*/
+
+#ifdef __DEBUG
+
+#ifndef __DEBUGSTREAM
+#define __DEBUGSTREAM
+
+
+class DebugStream
+{
+public:
+static void debug(const char* format, ...);
+static void release();
+static void breakPoint(const char* file, int line);
+private:
+
+};
+
+#undef DBG
+#undef DBG_END
+#undef BREAK
+
+///Debug output (if enabled), same syntax as printf, with heading info
+#define DBG(...) do{ DebugStream::debug("[%s:%s@%d] ", __FILE__, __FUNCTION__, __LINE__); DebugStream::debug(__VA_ARGS__); } while(0);
+
+///Debug output (if enabled), same syntax as printf, no heading info
+#define DBGL(...) do{ DebugStream::debug(__VA_ARGS__); } while(0);
+#define DBG_END DebugStream::release
+
+///Break point usin serial debug interface (if debug enbaled)
+#define BREAK() DebugStream::breakPoint(__FILE__, __LINE__)
+#endif
+
+#else
+#undef DBG
+#undef DBG_END
+#undef BREAK
+#define DBG(...)
+#define DBG_END()
+#define BREAK()
+#endif
+
+#ifdef __LWIP_DEBUG
+#ifndef __SNPRINTF
+#define __SNPRINTF
+#include "mbed.h"
+
+//int snprintf(char *str, int size, const char *format, ...);
+#endif
+#endif
+
+#ifdef __LWIP_DEBUG
+#undef __DEBUG
+#endif
+
+//#endif
+
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/drv/eth/eth_drv.cpp	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,212 @@
+
+/*
+Copyright (c) 2010 Donatien Garnier (donatiengar [at] gmail [dot] com)
+ 
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+ 
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+ 
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+#include "netCfg.h"
+#if NET_ETH
+
+#include "mbed.h"
+
+Ethernet *pEth = NULL;
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include "lwip/opt.h"
+
+#include "lwip/def.h"
+#include "lwip/pbuf.h"
+#include "lwip/sys.h"
+#include "lwip/stats.h"
+#include "netif/etharp.h"
+#include "string.h"
+
+//#include "eth_drv.h"
+
+#define IFNAME0 'E'
+#define IFNAME1 'X'
+
+#define min(x,y) (((x)<(y))?(x):(y))
+
+struct netif* eth_netif;
+
+static err_t eth_output(struct netif *netif, struct pbuf *p) {
+  #if ETH_PAD_SIZE
+    pbuf_header(p, -ETH_PAD_SIZE); /* drop the padding word */
+  #endif
+
+  do {
+    pEth->write((const char *)p->payload, p->len);
+  } while((p = p->next)!=NULL);
+
+  pEth->send();
+
+  #if ETH_PAD_SIZE
+    pbuf_header(p, ETH_PAD_SIZE); /* reclaim the padding word */
+  #endif
+  
+  LINK_STATS_INC(link.xmit);
+  return ERR_OK;
+}
+
+/*
+void show(char *buf, int size) {
+    printf("Destination:  %02hx:%02hx:%02hx:%02hx:%02hx:%02hx\n",
+            buf[0], buf[1], buf[2], buf[3], buf[4], buf[5]);
+    printf("Source: %02hx:%02hx:%02hx:%02hx:%02hx:%02hx\n",
+            buf[6], buf[7], buf[8], buf[9], buf[10], buf[11]);
+  
+    printf("Type %hd\n", htons((short)buf[12]));
+    
+   // hexview(buf, size);
+}
+*/
+
+void eth_poll() {
+  struct eth_hdr *ethhdr;
+  struct pbuf *frame, *p;
+  int len, read;
+
+  while((len = pEth->receive()) != 0) {
+      frame = pbuf_alloc(PBUF_RAW, len, PBUF_POOL);
+      if(frame == NULL) {
+          return;
+      }
+      p = frame;
+      /* no packet could be read, silently ignore this */
+      if (p == NULL) return;
+      do {
+         read = pEth->read((char *)p->payload, p->len);
+         p = p->next;
+      } while(p != NULL && read != 0);
+           
+      #if ETH_PAD_SIZE
+          pbuf_header(p, ETH_PAD_SIZE);
+      #endif
+
+      ethhdr = (struct eth_hdr *)(frame->payload);
+      
+     // show((char*)ethhdr, 13);
+      
+      /*
+      switch(htons(ethhdr->type)) {
+          
+          case ETHTYPE_IP:
+              etharp_ip_input(gnetif, frame);
+              pbuf_header(frame, -((s16_t) sizeof(struct eth_hdr)));
+              gnetif->input(frame, gnetif);
+              break;
+          
+          case ETHTYPE_ARP:
+              etharp_arp_input(gnetif, (struct eth_addr *)(gnetif->hwaddr), frame);
+              break;
+          
+          default:
+              break;
+      }*/
+      
+      
+      
+      //ethernet_input(frame, gnetif);
+      
+      switch (htons(ethhdr->type)) {
+      /* IP or ARP packet? */
+      case ETHTYPE_IP:
+      case ETHTYPE_ARP:
+      #if PPPOE_SUPPORT
+      /* PPPoE packet? */
+      case ETHTYPE_PPPOEDISC:
+      case ETHTYPE_PPPOE:
+      #endif /* PPPOE_SUPPORT */
+      /* full packet send to tcpip_thread to process */
+        //if (netif->input(p, gnetif)!=ERR_OK)
+        if (ethernet_input(frame, eth_netif)!=ERR_OK)
+        { LWIP_DEBUGF(NETIF_DEBUG, ("ethernetif_input: IP input error\n"));
+          pbuf_free(frame);
+          frame = NULL;
+        }
+        break;
+
+      default:
+        pbuf_free(frame);
+        frame = NULL;
+        break;
+      }
+      
+      /* pbuf_free(frame); */
+  }
+
+  
+ 
+  
+}
+
+err_t eth_init(struct netif *netif) {
+  LWIP_ASSERT("netif != NULL", (netif != NULL));
+  
+  NETIF_INIT_SNMP(netif, snmp_ifType_ethernet_csmacd, 0x2EA);
+  
+  /* maximum transfer unit */
+  netif->mtu = 0x2EA;
+  
+  /* device capabilities */
+  /* don't set NETIF_FLAG_ETHARP if this device is not an ethernet one */
+  netif->flags = NETIF_FLAG_BROADCAST | NETIF_FLAG_ETHARP | NETIF_FLAG_LINK_UP | NETIF_FLAG_IGMP;
+
+  netif->state = NULL;
+  eth_netif = netif;
+
+  netif->name[0] = IFNAME0;
+  netif->name[1] = IFNAME1;
+
+  /* We directly use etharp_output() here to save a function call.
+   * You can instead declare your own function an call etharp_output()
+   * from it if you have to do some checks before sending (e.g. if link
+   * is available...) */
+  netif->output          = etharp_output;
+  netif->linkoutput      = eth_output;
+
+  if (!pEth) pEth = new Ethernet(); // only create Ethernet object if required
+
+  return ERR_OK;
+}
+
+void eth_free()
+{
+  if(pEth)
+    delete pEth;
+  pEth = NULL;
+}
+
+void eth_address(char* mac) {
+    pEth->address(mac);
+}
+
+Ethernet* eth_interface() {
+    return pEth;
+}    
+
+#ifdef __cplusplus
+};
+#endif
+
+#endif
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/drv/eth/eth_drv.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,41 @@
+
+/*
+Copyright (c) 2010 Donatien Garnier (donatiengar [at] gmail [dot] com)
+ 
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+ 
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+ 
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+#ifndef ETHDRV_H
+#define ETHDRV_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+void eth_poll();
+err_t eth_init(struct netif* netif);
+void eth_address(char* mac);
+void eth_free();
+Ethernet* eth_interface();
+
+#ifdef __cplusplus
+};
+#endif
+
+#endif
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/if/eth/EthernetNetIf.cpp	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,192 @@
+#pragma diag_remark 1464
+/*
+Copyright (c) 2010 Donatien Garnier (donatiengar [at] gmail [dot] com)
+ 
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+ 
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+ 
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+#include "EthernetNetIf.h"
+
+#include "netif/etharp.h"
+#include "lwip/dhcp.h"
+#include "lwip/dns.h"
+#include "lwip/igmp.h"
+
+#include "drv/eth/eth_drv.h"
+#include "mbed.h"
+
+//#define __DEBUG
+#include "dbg/dbg.h"
+
+#include "netCfg.h"
+#if NET_ETH
+
+EthernetNetIf::EthernetNetIf(const char* hostname) : LwipNetIf(), m_ethArpTimer(), m_dhcpCoarseTimer(), m_dhcpFineTimer(), m_igmpTimer(), m_pNetIf(NULL),
+m_netmask(255,255,255,255), m_gateway(), m_hostname(hostname)
+{
+  //m_hostname = NULL;
+  m_pNetIf = new netif;
+  m_useDhcp = true;
+  m_pDhcp = new dhcp;
+  m_setup = false;
+}
+
+EthernetNetIf::EthernetNetIf(IpAddr ip, IpAddr netmask, IpAddr gateway, IpAddr dns) : LwipNetIf(), m_ethArpTimer(), m_dhcpCoarseTimer(), m_dhcpFineTimer(), m_igmpTimer(), m_pNetIf(NULL), m_hostname(NULL) //W/o DHCP
+{
+  m_hostname = NULL;
+  m_netmask = netmask;
+  m_gateway = gateway;
+  m_ip = ip;
+  m_pNetIf = new netif;
+  dns_setserver(0, &dns.getStruct());
+  m_useDhcp = false;
+  m_setup = false;
+}
+
+EthernetNetIf::~EthernetNetIf()
+{
+  if(m_pNetIf)
+  {
+    igmp_stop(m_pNetIf); //Stop IGMP processing
+    netif_set_down(m_pNetIf);
+    netif_remove(m_pNetIf);
+    delete m_pNetIf;
+    eth_free();
+  }
+  
+  if (m_pDhcp)
+    delete m_pDhcp;
+}
+  
+EthernetErr EthernetNetIf::setup(int timeout_ms /*= 15000*/)
+{
+  if (m_setup)
+  {
+    igmp_stop(m_pNetIf);
+    netif_set_down(m_pNetIf);
+    netif_remove(m_pNetIf);
+    delete m_pNetIf;
+    eth_free();
+    m_pNetIf = new netif;
+  }
+
+  LwipNetIf::init();
+  //m_ethArpTicker.attach_us(&etharp_tmr,  ARP_TMR_INTERVAL  * 1000); // = 5s in etharp.h
+  m_ethArpTimer.start();
+  if(m_useDhcp)
+  {
+    //m_dhcpCoarseTicker.attach(&dhcp_coarse_tmr, DHCP_COARSE_TIMER_SECS); // = 60s in dhcp.h
+    //m_dhcpFineTicker.attach_us(&dhcp_fine_tmr, DHCP_FINE_TIMER_MSECS * 1000); // = 500ms in dhcp.h
+    m_dhcpCoarseTimer.start();
+    m_dhcpFineTimer.start();
+  }
+  m_pNetIf->hwaddr_len = ETHARP_HWADDR_LEN; //6
+  eth_address((char *)m_pNetIf->hwaddr);
+  
+  DBG("HW Addr is : %02x:%02x:%02x:%02x:%02x:%02x.\n", 
+  m_pNetIf->hwaddr[0], m_pNetIf->hwaddr[1], m_pNetIf->hwaddr[2],
+  m_pNetIf->hwaddr[3], m_pNetIf->hwaddr[4], m_pNetIf->hwaddr[5]);
+
+  m_pNetIf = netif_add(m_pNetIf, &(m_ip.getStruct()), &(m_netmask.getStruct()), &(m_gateway.getStruct()), NULL, eth_init, ip_input);//ethernet_input);// ip_input);
+  m_pNetIf->hostname = (char *)m_hostname;
+  netif_set_default(m_pNetIf);
+  
+  //DBG("\r\nStarting DHCP.\r\n");
+  
+  if(m_useDhcp)
+  {
+    dhcp_set_struct(m_pNetIf, m_pDhcp);
+    dhcp_start(m_pNetIf);
+    DBG("DHCP Started, waiting for IP...\n");
+  }
+  else
+  {
+    netif_set_up(m_pNetIf);
+  }
+  
+  Timer timeout;
+  timeout.start();
+  while( !netif_is_up(m_pNetIf) ) //Wait until device is up
+  {
+    if(m_useDhcp)
+    {
+      if(m_dhcpFineTimer.read_ms()>=DHCP_FINE_TIMER_MSECS)
+      {
+        m_dhcpFineTimer.reset();
+        dhcp_fine_tmr();
+      }
+      if(m_dhcpCoarseTimer.read()>=DHCP_COARSE_TIMER_SECS)
+      {
+        m_dhcpCoarseTimer.reset();
+        dhcp_coarse_tmr();
+      }
+    }
+    poll();
+    if( timeout.read_ms() > timeout_ms )
+    {
+      //Abort
+      if(m_useDhcp)
+        dhcp_stop(m_pNetIf);
+      else
+        netif_set_down(m_pNetIf);
+      DBG("\r\nTimeout.\r\n");
+      m_setup = true;
+      return ETH_TIMEOUT;
+    }
+  }
+  
+  #if LWIP_IGMP
+  igmp_start(m_pNetIf); //Start IGMP processing
+  #endif
+  
+  m_ip = IpAddr(&(m_pNetIf->ip_addr));
+   
+  DBG("Connected, IP : %d.%d.%d.%d\n", m_ip[0], m_ip[1], m_ip[2], m_ip[3]);
+  
+  m_setup = true;
+  return ETH_OK;
+}
+
+void EthernetNetIf::poll()
+{
+  if(m_ethArpTimer.read_ms()>=ARP_TMR_INTERVAL)
+  {
+    m_ethArpTimer.reset();
+    etharp_tmr();
+  }
+  #if LWIP_IGMP
+  if(m_igmpTimer.read_ms()>=IGMP_TMR_INTERVAL)
+  {
+    m_igmpTimer.reset();
+    igmp_tmr();
+  }
+  #endif
+  LwipNetIf::poll();
+  eth_poll();
+}
+
+const char* EthernetNetIf::getHwAddr() const {
+    return (char*)m_pNetIf->hwaddr;
+}
+
+const char* EthernetNetIf::getHostname() const {
+    return m_hostname;
+}
+
+#endif
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/if/eth/EthernetNetIf.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,109 @@
+
+/*
+Copyright (c) 2010 Donatien Garnier (donatiengar [at] gmail [dot] com)
+ 
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+ 
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+ 
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+/** \file
+Ethernet network interface header file
+*/
+
+#ifndef ETHERNETNETIF_H
+#define ETHERNETNETIF_H
+
+struct netif;
+
+#include "mbed.h"
+
+#include "if/lwip/LwipNetIf.h"
+#include "lwip/dhcp.h"
+
+///Ethernet network interface return codes
+enum EthernetErr
+{
+  __ETH_MIN = -0xFFFF,
+  ETH_TIMEOUT, ///<Timeout during setup
+  ETH_OK = 0 ///<Success
+};
+
+///Ethernet network interface
+/**
+This class provides Ethernet connectivity to the stack
+*/
+class EthernetNetIf : public LwipNetIf
+{
+public:
+  ///Instantiates the Interface and register it against the stack, DHCP will be used
+  /**
+  * An optional hostname can be specified which will be passed to the DHCP server.
+  * Examples without and with hostname specified:
+  *
+  * @code
+  * EthernetNetIf eth();
+  * @endcode
+  * @code
+  * EthernetNetIf eth("mbedSE");
+  * @endcode
+  */
+  EthernetNetIf(const char* hostname = NULL); //W/ DHCP
+
+  ///Instantiates the Interface and register it against the stack, DHCP will not be used
+  /**
+  IpAddr is a container class that can be constructed with either 4 bytes or no parameters for a null IP address.
+  */
+  EthernetNetIf(IpAddr ip, IpAddr netmask, IpAddr gateway, IpAddr dns); //W/o DHCP
+  virtual ~EthernetNetIf();
+  
+  ///Brings the interface up
+  /**
+  Uses DHCP if necessary
+  @param timeout_ms : You can set the timeout parameter in milliseconds, if not it defaults to 15s
+  @return : ETH_OK on success or ETH_TIMEOUT on timeout
+  */
+  EthernetErr setup(int timeout_ms = 15000);
+
+  virtual void poll();
+  
+  ///Returns an array containing the hardware address
+  const char* getHwAddr() const;
+  
+    ///Returns a pointer to the hostname set in the constructor
+  const char* getHostname() const;
+  
+private:
+  Timer m_ethArpTimer;
+  Timer m_dhcpCoarseTimer;
+  Timer m_dhcpFineTimer;
+  Timer m_igmpTimer;
+    
+  bool m_useDhcp;
+
+  netif* m_pNetIf;
+  
+  IpAddr m_netmask;
+  IpAddr m_gateway;
+  
+  const char* m_hostname;
+  dhcp* m_pDhcp;
+  bool m_setup;
+};
+
+#endif
+
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/if/lwip/LwipNetIf.cpp	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,98 @@
+
+/*
+Copyright (c) 2010 Donatien Garnier (donatiengar [at] gmail [dot] com)
+ 
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+ 
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+ 
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+#include "LwipNetIf.h"
+#include "lwip/init.h"
+#include "lwip/tcp_impl.h"
+#include "lwip/dns.h"
+
+#include "lwipNetTcpSocket.h"
+#include "lwipNetUdpSocket.h"
+#include "lwipNetDnsRequest.h"
+
+#include "netCfg.h"
+#if NET_LWIP_STACK
+
+//See doc/rawapi.txt for details
+
+LwipNetIf::LwipNetIf() : NetIf(), m_tcpTimer(), m_dnsTimer(), m_init(false)
+{  
+
+}
+
+
+LwipNetIf::~LwipNetIf()
+{
+
+}
+
+void LwipNetIf::init()
+{
+  if(m_init)
+    return;
+  m_init=true;
+  lwip_init(); //init lwip, see init.c for details
+  
+  //Setup Clocks
+  m_tcpTimer.start();
+  m_dnsTimer.start();
+  //m_tcpTicker.attach_us( tcp_tmr, TCP_TMR_INTERVAL * 1000 ); //TCP_TMR_INTERVAL = 250 ms in tcp_impl.h
+  //m_dnsTicker.attach_us( dns_tmr, DNS_TMR_INTERVAL * 1000 ); //DNS_TMR_INTERVAL = 1000 ms in dns.h
+}
+
+NetTcpSocket* LwipNetIf::tcpSocket()  //Create a new tcp socket
+{
+  return new LwipNetTcpSocket();
+}
+
+NetUdpSocket* LwipNetIf::udpSocket()  //Create a new udp socket
+{
+  return new LwipNetUdpSocket();
+}
+
+NetDnsRequest* LwipNetIf::dnsRequest(const char* hostname) //Create a new NetDnsRequest object
+{
+  return new LwipNetDnsRequest(hostname);
+}
+
+NetDnsRequest* LwipNetIf::dnsRequest(Host* pHost) //Create a new NetDnsRequest object
+{
+  return new LwipNetDnsRequest(pHost);
+}
+
+void LwipNetIf::poll()
+{
+  if(m_init && m_tcpTimer.read_ms() >= TCP_TMR_INTERVAL)
+  {
+    m_tcpTimer.reset();
+    tcp_tmr(); //Poll LwIP
+  }
+  if(m_init && m_dnsTimer.read_ms() >= DNS_TMR_INTERVAL)
+  {
+    m_dnsTimer.reset();
+    dns_tmr();
+  }
+  //Do some stuff...
+}
+
+#endif
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/if/lwip/LwipNetIf.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,62 @@
+
+/*
+Copyright (c) 2010 Donatien Garnier (donatiengar [at] gmail [dot] com)
+ 
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+ 
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+ 
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+#ifndef LWIPNETIF_H
+#define LWIPNETIF_H
+
+//class Ticker;
+#include "mbed.h"
+
+#define NET_LWIP_STACK 1
+#include "core/net.h"
+#include "if/net/netif.h"
+/*
+#include "lwipNetTcpSocket.h"
+#include "lwipNetUdpSocket.h"
+#include "lwipNetDnsRequest.h"
+*/
+
+class LwipNetIf : public NetIf
+{
+public:
+  LwipNetIf();
+  virtual ~LwipNetIf();
+  
+  void init();
+
+  virtual NetTcpSocket* tcpSocket();  //Create a new tcp socket
+  virtual NetUdpSocket* udpSocket();  //Create a new udp socket
+  virtual NetDnsRequest* dnsRequest(const char* hostname); //Create a new NetDnsRequest object
+  virtual NetDnsRequest* dnsRequest(Host* pHost); //Create a new NetDnsRequest object
+
+  virtual void poll();
+
+private:
+  Timer m_tcpTimer;
+  Timer m_dnsTimer;
+  
+  bool m_init;
+
+};
+
+#endif
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/if/lwip/lwipNetDnsRequest.cpp	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,152 @@
+
+/*
+Copyright (c) 2010 Donatien Garnier (donatiengar [at] gmail [dot] com)
+ 
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+ 
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+ 
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+#include "lwipNetDnsRequest.h"
+#include "lwip/err.h" //err_t, ERR_xxx
+#include "lwip/dns.h"
+
+#include "netCfg.h"
+#if NET_LWIP_STACK
+
+//#define __DEBUG
+#include "dbg/dbg.h"
+
+LwipNetDnsRequest::LwipNetDnsRequest(const char* hostname) : NetDnsRequest(hostname), m_state(LWIPNETDNS_START), m_cbFired(false), m_closing(false)
+{
+  DBG("New LwipNetDnsRequest %p\n", this);
+}
+
+LwipNetDnsRequest::LwipNetDnsRequest(Host* pHost) : NetDnsRequest(pHost), m_state(LWIPNETDNS_START), m_cbFired(false), m_closing(false)
+{
+  DBG("New LwipNetDnsRequest %p\n", this);
+}
+
+LwipNetDnsRequest::~LwipNetDnsRequest()
+{
+  DBG("LwipNetDnsRequest %p destroyed\n", this);
+}
+
+/*
+Main useful function here (see lwip/dns.h):
+err_t          dns_gethostbyname(const char *hostname, ip_addr_t *addr,
+                                 dns_found_callback found, void *callback_arg);
+*/
+
+//Execute request & return OK if found, NOTFOUND or ERROR on error, or PROCESSING if the request has not completed yet
+void LwipNetDnsRequest::poll()
+{
+  err_t  err;
+  switch(m_state)
+  {
+  case LWIPNETDNS_START: //First req, let's call dns_gethostbyname
+    ip_addr_t ipStruct;
+    err = dns_gethostbyname(m_hostname, &ipStruct, LwipNetDnsRequest::sFoundCb, (void*) this );
+    if( err == ERR_OK )
+    {
+      m_ip = IpAddr(&ipStruct);
+      m_state = LWIPNETDNS_OK;
+      DBG("DNS: Ip found in cache.\n");
+    }
+    else if( err == ERR_INPROGRESS)
+    {
+      DBG("DNS: Processing.\n");
+      m_state = LWIPNETDNS_PROCESSING;
+    }
+    else //Likely ERR_VAL
+    {
+      DBG("DNS: Error on init.\n");
+      m_state = LWIPNETDNS_ERROR;
+    }
+    break;
+  case LWIPNETDNS_PROCESSING:
+    break; //Nothing to do, DNS is polled on interrupt
+  case LWIPNETDNS_OK:
+    if(!m_cbFired)
+    {
+      DBG("DNS: Ip found.\n");
+      m_cbFired = true;
+      onReply(NETDNS_FOUND); //Raise callback
+    }
+    break;
+  case LWIPNETDNS_NOTFOUND:
+    if(!m_cbFired)
+    {
+      DBG("DNS: could not be resolved.\n");
+      m_cbFired = true;
+      onReply(NETDNS_NOTFOUND); //Raise callback
+    }  
+    break;  
+  case LWIPNETDNS_ERROR:
+  default:
+    if(!m_cbFired)
+    {
+      DBG("DNS: Error.\n");
+      m_cbFired = true;
+      onReply(NETDNS_ERROR); //Raise callback
+    }  
+    break; 
+  }
+  if(m_closing && (m_state!=LWIPNETDNS_PROCESSING)) //Check wether the closure has been reqd
+  {
+    DBG("LwipNetDnsRequest: Closing in poll()\n");
+    NetDnsRequest::close();
+  }
+}
+
+void LwipNetDnsRequest::close()
+{
+  DBG("LwipNetDnsRequest: Close req\n");
+  if(m_state!=LWIPNETDNS_PROCESSING)
+  {
+    DBG("LwipNetDnsRequest: Closing in close()\n");
+    NetDnsRequest::close();
+  }
+  else //Cannot close rightaway, waiting for callback from underlying layer
+  {
+    m_closing = true;
+  }
+}
+
+void LwipNetDnsRequest::foundCb(const char *name, ip_addr_t *ipaddr)
+{
+  if( ipaddr == NULL )
+  {
+    DBG("LwipNetDnsRequest: Callback: Name not found\n");
+    m_state = LWIPNETDNS_NOTFOUND;
+    return;
+  }
+  DBG("LwipNetDnsRequest: Callback: Resolved\n");
+  m_ip = IpAddr(ipaddr);
+  m_state = LWIPNETDNS_OK;
+}
+
+
+void LwipNetDnsRequest::sFoundCb(const char *name, ip_addr_t *ipaddr, void *arg)
+{
+  DBG("LwipNetDnsRequest: Static callback\n");
+  LwipNetDnsRequest* pMe = (LwipNetDnsRequest*) arg;
+  return pMe->foundCb( name, ipaddr );
+}
+
+#endif
+
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/if/lwip/lwipNetDnsRequest.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,67 @@
+
+/*
+Copyright (c) 2010 Donatien Garnier (donatiengar [at] gmail [dot] com)
+ 
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+ 
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+ 
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+#ifndef LWIPNETDNSREQUEST_H
+#define LWIPNETDNSREQUEST_H
+
+#define NET_LWIP_STACK 1
+#include "if/net/netdnsrequest.h"
+
+//struct ip_addr_t;
+#include "lwip/ip_addr.h"
+
+class LwipNetDnsRequest : public NetDnsRequest
+{
+public:
+  LwipNetDnsRequest(const char* hostname);
+  LwipNetDnsRequest(Host* pHost);
+  virtual ~LwipNetDnsRequest();
+
+  //Execute request & return OK if found, NOTFOUND or ERROR on error, or PROCESSING if the request has not completed yet
+  virtual void poll();
+  
+  virtual void close();
+
+protected:
+  void foundCb(const char *name, ip_addr_t *ipaddr);
+  
+private:
+  enum LwipNetDnsState
+  {
+    LWIPNETDNS_START,
+    LWIPNETDNS_PROCESSING, //Req has not completed
+    LWIPNETDNS_NOTFOUND,
+    LWIPNETDNS_ERROR,
+    LWIPNETDNS_OK
+  };
+
+  LwipNetDnsState m_state;
+  bool m_cbFired;
+  
+  //Static callbacks : Transforms into a C++ callback
+  static void sFoundCb(const char *name, ip_addr_t *ipaddr, void *arg);
+  
+  bool m_closing;
+};
+
+#endif
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/if/lwip/lwipNetTcpSocket.cpp	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,456 @@
+
+/*
+Copyright (c) 2010 Donatien Garnier (donatiengar [at] gmail [dot] com)
+ 
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+ 
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+ 
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+#include "lwipNetTcpSocket.h"
+#include "lwip/tcp.h"
+
+//#define __DEBUG
+#include "dbg/dbg.h"
+
+#include "netCfg.h"
+#if NET_LWIP_STACK
+
+LwipNetTcpSocket::LwipNetTcpSocket(tcp_pcb* pPcb /*= NULL*/) : NetTcpSocket(), m_pPcb(pPcb), m_lpInNetTcpSocket(), //Passes a pcb if already created (by an accept req for instance), in that case transfers ownership
+m_pReadPbuf(NULL)
+{
+  DBG("New NetTcpSocket %p\n", (void*)this);
+  if(!m_pPcb)
+  {
+    m_pPcb = tcp_new();
+    DBG("Creating new PCB %p\n", m_pPcb);
+  }
+  if(m_pPcb)
+  {
+    //Setup callbacks
+    tcp_arg( (tcp_pcb*) m_pPcb, (void*) this ); //this will be passed to each static callback
+    
+    tcp_recv( (tcp_pcb*) m_pPcb, LwipNetTcpSocket::sRecvCb );
+    tcp_sent((tcp_pcb*) m_pPcb, LwipNetTcpSocket::sSentCb );
+    tcp_err( (tcp_pcb*) m_pPcb, LwipNetTcpSocket::sErrCb );
+    //Connected callback is defined in connect()
+    //Accept callback is defined in listen()
+    DBG("NetTcpSocket created.\n");
+  }
+}
+
+LwipNetTcpSocket::~LwipNetTcpSocket()
+{
+/*  if(m_pPcb)
+    tcp_close( (tcp_pcb*) m_pPcb); //Disconnect & free pcb*/
+  close();
+}
+  
+NetTcpSocketErr LwipNetTcpSocket::bind(const Host& me)
+{
+  if(!m_pPcb)
+    return NETTCPSOCKET_MEM; //NetTcpSocket was not properly initialised, should destroy it & retry
+    
+  err_t err = tcp_bind( (tcp_pcb*) m_pPcb, IP_ADDR_ANY, me.getPort()); //IP_ADDR_ANY : Bind the connection to all local addresses
+  if(err)
+    return NETTCPSOCKET_INUSE;
+    
+  return NETTCPSOCKET_OK;
+}
+
+NetTcpSocketErr LwipNetTcpSocket::listen()
+{
+  if(!m_pPcb)
+    return NETTCPSOCKET_MEM; //NetTcpSocket was not properly initialised, should destroy it & retry
+/*
+  From doc/rawapi.txt :
+  
+  The tcp_listen() function returns a new connection identifier, and
+  the one passed as an argument to the function will be
+  deallocated. The reason for this behavior is that less memory is
+  needed for a connection that is listening, so tcp_listen() will
+  reclaim the memory needed for the original connection and allocate a
+  new smaller memory block for the listening connection.
+*/
+
+//  tcp_pcb* pNewPcb = tcp_listen(m_pPcb);
+  tcp_pcb* pNewPcb = tcp_listen_with_backlog((tcp_pcb*)m_pPcb, 5);
+  if( !pNewPcb ) //Not enough memory to create the listening pcb
+    return NETTCPSOCKET_MEM;
+
+  m_pPcb = pNewPcb;
+  
+  tcp_accept( (tcp_pcb*) m_pPcb, LwipNetTcpSocket::sAcceptCb );
+
+  return NETTCPSOCKET_OK;
+}
+
+NetTcpSocketErr LwipNetTcpSocket::connect(const Host& host)
+{
+  if(!m_pPcb)
+    return NETTCPSOCKET_MEM; //NetTcpSocket was not properly initialised, should destroy it & retry
+  
+  ip_addr_t ip = host.getIp().getStruct();
+  err_t err = tcp_connect( (tcp_pcb*) m_pPcb, &ip, host.getPort(), LwipNetTcpSocket::sConnectedCb );
+  
+  if(err)
+    return NETTCPSOCKET_MEM;
+    
+  return NETTCPSOCKET_OK;
+}
+
+NetTcpSocketErr LwipNetTcpSocket::accept(Host* pClient, NetTcpSocket** ppNewNetTcpSocket)
+{
+  if( !m_pPcb ) //Pcb doesn't exist (anymore)
+    return NETTCPSOCKET_MEM;
+  //Dequeue a connection
+  //if( m_lpInPcb.empty() )
+  if( m_lpInNetTcpSocket.empty() )
+    return NETTCPSOCKET_EMPTY;
+  
+  tcp_accepted( ((tcp_pcb*) m_pPcb) ); //Should fire proper events //WARN: m_pPcb is the GOOD param here (and not pInPcb)
+  
+/*  tcp_pcb* pInPcb = m_lpInPcb.front();
+  m_lpInPcb.pop();*/
+  
+  if( (m_lpInNetTcpSocket.front()) == NULL )
+  {
+    m_lpInNetTcpSocket.pop();
+    return NETTCPSOCKET_RST;
+  }
+  
+  if( (m_lpInNetTcpSocket.front())->m_closed )
+  {
+    Net::releaseTcpSocket(m_lpInNetTcpSocket.front());
+    m_lpInNetTcpSocket.pop();
+    return NETTCPSOCKET_RST;
+  }
+  
+  ip_addr_t* ip = (ip_addr_t*) &( (m_lpInNetTcpSocket.front()->m_pPcb)->remote_ip);
+  
+  *ppNewNetTcpSocket = m_lpInNetTcpSocket.front();
+  *pClient = Host(
+    IpAddr( 
+      ip
+    ), 
+    m_lpInNetTcpSocket.front()->m_pPcb->remote_port 
+  );
+  m_lpInNetTcpSocket.pop();
+//  *pClient = Host( IpAddr(pInPcb->remote_ip), pInPcb->remote_port );
+  
+  //Return a new socket
+ // *ppNewNetTcpSocket = (NetTcpSocket*) new LwipNetTcpSocket(pInPcb);
+
+  //tcp_accepted( ((tcp_pcb*) m_pPcb) ); //Should fire proper events //WARN: m_pPcb is the GOOD param here (and not pInPcb)
+  
+/*  if(*ppNewNetTcpSocket == NULL)
+  {
+    DBG("Not enough mem, socket dropped in LwipNetTcpSocket::accept.\n");
+    tcp_abort(pInPcb);
+  }*/
+  
+  return NETTCPSOCKET_OK;
+}
+
+#define MAX(a,b) (((a)>(b))?(a):(b))
+#define MIN(a,b) (((a)<(b))?(a):(b))
+
+int /*if < 0 : NetTcpSocketErr*/ LwipNetTcpSocket::send(const char* buf, int len)
+{
+  if( !m_pPcb ) //Pcb doesn't exist (anymore)
+    return NETTCPSOCKET_MEM;
+  int outLen = MIN( len, tcp_sndbuf( (tcp_pcb*) m_pPcb) ); 
+  //tcp_sndbuf() returns the number of bytes available in the output queue, so never go above it
+  err_t err = tcp_write( (tcp_pcb*) m_pPcb, (void*) buf, outLen, TCP_WRITE_FLAG_COPY );
+  //Flags are TCP_WRITE_FLAG_COPY & TCP_WRITE_FLAG_MORE (see tcp_out.c) :
+  //If TCP_WRITE_FLAG_MORE is not set ask client to push buffered data to app
+  if(err)
+  {
+    switch( err )
+    {
+    case ERR_CONN:
+      return (int) NETTCPSOCKET_SETUP; //Not connected properly
+    case ERR_ARG:
+      return (int) NETTCPSOCKET_SETUP; //Wrong args ! (like buf pointing to NULL)
+    case ERR_MEM:
+    default:
+      return (int) NETTCPSOCKET_MEM; //Not enough memory
+    }
+  }
+  return outLen;
+}
+
+int /*if < 0 : NetTcpSocketErr*/ LwipNetTcpSocket::recv(char* buf, int len)
+{
+  if( !m_pPcb ) //Pcb doesn't exist (anymore)
+    return NETTCPSOCKET_MEM;
+  int inLen = 0;
+  int cpyLen = 0;
+  
+  static int rmgLen = 0; 
+  //Contains the remaining len in this pbuf
+  
+  if( !m_pReadPbuf )
+  {
+    rmgLen = 0;
+    return 0;
+  }
+  
+  if ( !rmgLen ) //We did not know m_pReadPbuf->len last time we called this fn
+  {
+    rmgLen = m_pReadPbuf->len;
+  }
+  
+  while ( inLen < len )
+  {
+    cpyLen = MIN( (len - inLen), rmgLen ); //Remaining len to copy, remaining len in THIS pbuf
+    memcpy((void*)buf, (void*)((char*)(m_pReadPbuf->payload) + (m_pReadPbuf->len - rmgLen)), cpyLen);
+    inLen += cpyLen;
+    buf += cpyLen;
+    
+    rmgLen = rmgLen - cpyLen; //Update rmgLen
+    
+    if( rmgLen > 0 )
+    {
+      //We did not read this pbuf completely, so let's save it's pos & return
+      break;
+    }
+    
+    if(m_pReadPbuf->next)
+    {
+      pbuf* pNextPBuf = m_pReadPbuf->next;
+      m_pReadPbuf->next = NULL; //So that it is not freed as well
+      //We get the reference to pNextPBuf from m_pReadPbuf
+      pbuf_free((pbuf*)m_pReadPbuf);
+      m_pReadPbuf = pNextPBuf;
+      rmgLen = m_pReadPbuf->len;
+    }
+    else
+    {
+      pbuf_free((pbuf*)m_pReadPbuf);
+      m_pReadPbuf = NULL;
+      rmgLen = 0;
+      break; //No more data to read
+    }
+    
+  }
+  
+  //tcp_recved(m_pPcb, inLen); //Acknowledge the reception
+  
+  return inLen;
+}
+
+NetTcpSocketErr LwipNetTcpSocket::close()
+{
+  //DBG("LwipNetTcpSocket::close() : Closing...\n");
+
+  if(m_closed)
+    return NETTCPSOCKET_OK; //Already being closed
+  m_closed = true;
+  
+  if( !m_pPcb ) //Pcb doesn't exist (anymore)
+    return NETTCPSOCKET_MEM;
+    
+  //Cleanup incoming data
+  cleanUp();
+ 
+  if( !!tcp_close( (tcp_pcb*) m_pPcb) )
+  {
+    DBG("LwipNetTcpSocket::close() could not close properly, abort.\n");
+    tcp_abort( (tcp_pcb*) m_pPcb);
+    m_pPcb = NULL;
+    return NETTCPSOCKET_MEM;
+  }
+  
+  DBG("LwipNetTcpSocket::close() : connection closed successfully.\n");
+  
+  m_pPcb = NULL;
+  return NETTCPSOCKET_OK;
+}
+
+NetTcpSocketErr LwipNetTcpSocket::poll()
+{
+  NetTcpSocket::flushEvents();
+  return NETTCPSOCKET_OK;
+}
+
+// Callbacks events
+
+err_t LwipNetTcpSocket::acceptCb(struct tcp_pcb *newpcb, err_t err)
+{
+  if(err)
+  {
+    DBG("Error %d in LwipNetTcpSocket::acceptCb.\n", err);
+    return err;
+  }
+  //FIXME: MEM Errs
+  //m_lpInPcb.push(newpcb); //Add connection to the queue
+  LwipNetTcpSocket* pNewNetTcpSocket = new LwipNetTcpSocket(newpcb);
+  
+  if(pNewNetTcpSocket == NULL)
+  {
+    DBG("Not enough mem, socket dropped in LwipNetTcpSocket::acceptCb.\n");
+    tcp_abort(newpcb);
+    return ERR_ABRT;
+  }
+  
+  pNewNetTcpSocket->m_refs++;
+  m_lpInNetTcpSocket.push( pNewNetTcpSocket );
+  
+ // tcp_accepted(newpcb);
+ // tcp_accepted( m_pPcb ); //Should fire proper events //WARN: m_pPcb is the GOOD param here (and not pInPcb)
+  queueEvent(NETTCPSOCKET_ACCEPT);
+  return ERR_OK;
+}
+
+err_t LwipNetTcpSocket::connectedCb(struct tcp_pcb *tpcb, err_t err)
+{
+  queueEvent(NETTCPSOCKET_CONNECTED);
+  return ERR_OK;
+}
+
+void LwipNetTcpSocket::errCb(err_t err)
+{
+  DBG("NetTcpSocket %p - Error %d in LwipNetTcpSocket::errCb.\n", (void*)this, err);
+  //WARN: At this point, m_pPcb has been freed by lwIP
+  m_pPcb = NULL;
+  //These errors are fatal, discard all events queued before so that the errors are handled first
+  discardEvents();
+  m_closed = true;
+  cleanUp();
+  if( err == ERR_ABRT)
+    queueEvent(NETTCPSOCKET_CONABRT);
+  else //if( err == ERR_RST)
+    queueEvent(NETTCPSOCKET_CONRST);
+}
+  
+err_t LwipNetTcpSocket::sentCb(tcp_pcb* tpcb, u16_t len)
+{
+//  DBG("%d bytes ACKed by host.\n", len);
+  queueEvent(NETTCPSOCKET_WRITEABLE);
+  return ERR_OK;
+}
+
+err_t LwipNetTcpSocket::recvCb(tcp_pcb* tpcb, pbuf *p, err_t err)
+{
+  //Store pbuf ptr
+ // DBG("Receive CB with err = %d & len = %d.\n", err, p->tot_len);
+//  tcp_recved( (tcp_pcb*) m_pPcb, p->tot_len); //Acknowledge the reception
+  
+  if(err)
+  {
+    queueEvent(NETTCPSOCKET_ERROR);
+    return ERR_OK; //FIXME: More robust error handling there
+  }
+  else if(!p)
+  {
+    DBG("NetTcpSocket %p - Connection closed by remote host (LwipNetTcpSocket::recvCb).\n", (void*)this);
+    //Buf is NULL, that means that the connection has been closed by remote host
+    
+    //FIX: 27/05/2010: We do not want to deallocate the socket while some data might still be readable
+    //REMOVED:   close();
+ 
+    //However we do not want to close the socket yet
+ 
+    queueEvent(NETTCPSOCKET_DISCONNECTED);
+    return ERR_OK; 
+  }
+  
+  //We asserted that p is a valid pointer
+
+  //New data processing
+  tcp_recved( tpcb, p->tot_len); //Acknowledge the reception
+  if(!m_pReadPbuf)
+  {
+    m_pReadPbuf = p;
+    queueEvent(NETTCPSOCKET_READABLE);
+  }
+  else
+  {
+    pbuf_cat((pbuf*)m_pReadPbuf, p); //m_pReadPbuf is not empty, tail p to it and drop our ref
+    //No need to queue an event in that case since the read buf has not been processed yet
+  }
+  return ERR_OK;
+}
+
+
+void LwipNetTcpSocket::cleanUp() //Flush input buffer
+{
+  //Ensure that further error won't be followed to this inst (which can be destroyed)
+  if( m_pPcb )
+  {
+    tcp_arg( (tcp_pcb*) m_pPcb, (void*) NULL );
+    tcp_recv( (tcp_pcb*) m_pPcb, NULL );
+    tcp_sent((tcp_pcb*) m_pPcb, NULL );
+    tcp_err( (tcp_pcb*) m_pPcb, NULL );
+  }
+  
+  if( m_pReadPbuf )
+  {
+    DBG("Deallocating unread data.\n");
+    pbuf_free((pbuf*)m_pReadPbuf); //Free all unread data
+    m_pReadPbuf = NULL;
+    recv(NULL,0); //Update recv ptr position
+  }
+}
+
+// Static callbacks from LwIp
+
+err_t LwipNetTcpSocket::sAcceptCb(void *arg, struct tcp_pcb *newpcb, err_t err)
+{
+  LwipNetTcpSocket* pMe = (LwipNetTcpSocket*) arg;
+  return pMe->acceptCb( newpcb, err );
+}
+
+err_t LwipNetTcpSocket::sConnectedCb(void *arg, struct tcp_pcb *tpcb, err_t err)
+{
+  LwipNetTcpSocket* pMe = (LwipNetTcpSocket*) arg;
+  return pMe->connectedCb( tpcb, err );
+}
+
+void LwipNetTcpSocket::sErrCb(void *arg, err_t err)
+{
+  if( !arg )
+  {
+    DBG("NetTcpSocket - Error %d in LwipNetTcpSocket::sErrCb.\n", err);
+    return; //The socket has been destroyed, discard error
+  }
+  LwipNetTcpSocket* pMe = (LwipNetTcpSocket*) arg;
+  return pMe->errCb( err );
+}
+  
+err_t LwipNetTcpSocket::sSentCb(void *arg, struct tcp_pcb *tpcb, u16_t len)
+{
+  LwipNetTcpSocket* pMe = (LwipNetTcpSocket*) arg;
+  return pMe->sentCb( tpcb, len );
+}
+
+err_t LwipNetTcpSocket::sRecvCb(void *arg, struct tcp_pcb *tpcb, struct pbuf *p, err_t err)
+{
+  if( tpcb->flags & TF_RXCLOSED )
+  {
+    //The Pcb is in a closing state
+    //Discard that data here since we might have destroyed the corresponding socket object
+    tcp_recved( tpcb, p->tot_len);
+    pbuf_free( p );    
+    return ERR_OK;
+  }
+  LwipNetTcpSocket* pMe = (LwipNetTcpSocket*) arg;
+  return pMe->recvCb( tpcb, p, err );
+}
+
+#endif
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/if/lwip/lwipNetTcpSocket.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,90 @@
+
+/*
+Copyright (c) 2010 Donatien Garnier (donatiengar [at] gmail [dot] com)
+ 
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+ 
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+ 
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+#ifndef LWIPNETTCPSOCKET_H
+#define LWIPNETTCPSOCKET_H
+
+#define NET_LWIP_STACK 1
+#include "if/net/nettcpsocket.h"
+#include "LwipNetIf.h"
+
+#include "stdint.h"
+
+//Implements NetTcpSockets over lwIP raw API
+
+struct tcp_pcb; //Represents a Tcp Connection, "Protocol Control Block", see rawapi.txt & tcp.h
+struct pbuf; //Lwip Buffer Container
+
+typedef signed char err_t;
+typedef uint16_t u16_t;
+
+class LwipNetTcpSocket: public NetTcpSocket
+{
+public:
+  LwipNetTcpSocket(tcp_pcb* pPcb = NULL); //Passes a pcb if already created (by an accept req for instance), in that case transfers ownership
+  virtual ~LwipNetTcpSocket();
+  
+  virtual NetTcpSocketErr bind(const Host& me);
+  virtual NetTcpSocketErr listen();
+  virtual NetTcpSocketErr connect(const Host& host);
+  virtual NetTcpSocketErr accept(Host* pClient, NetTcpSocket** ppNewNetTcpSocket);
+  
+  virtual int /*if < 0 : NetTcpSocketErr*/ send(const char* buf, int len);
+  virtual int /*if < 0 : NetTcpSocketErr*/ recv(char* buf, int len);
+
+  virtual NetTcpSocketErr close();
+
+  virtual NetTcpSocketErr poll();
+  
+protected:
+  volatile tcp_pcb* m_pPcb;
+  
+  //Events callbacks from lwIp
+  err_t acceptCb(tcp_pcb* newpcb, err_t err);
+  err_t connectedCb(tcp_pcb* tpcb, err_t err);
+  
+  void errCb(err_t err);
+  
+  err_t sentCb(tcp_pcb* tpcb, u16_t len);
+  err_t recvCb(tcp_pcb* tpcb, pbuf *p, err_t err);
+  
+private:
+  void cleanUp(); //Flush input buffer
+
+//  queue<tcp_pcb*> m_lpInPcb; //Incoming connections that have not been accepted yet
+  queue<LwipNetTcpSocket*> m_lpInNetTcpSocket; //Incoming connections that have not been accepted yet
+  
+  volatile pbuf* m_pReadPbuf; //Ptr to read buffer
+  
+  //Static callbacks : Transforms into a C++ callback
+  static err_t sAcceptCb(void *arg, struct tcp_pcb *newpcb, err_t err);
+  static err_t sConnectedCb(void *arg, struct tcp_pcb *tpcb, err_t err);
+  
+  static void sErrCb(void *arg, err_t err);
+  
+  static err_t sSentCb(void *arg, struct tcp_pcb *tpcb, u16_t len);
+  static err_t sRecvCb(void *arg, struct tcp_pcb *tpcb, struct pbuf *p, err_t err);
+  
+};
+
+#endif
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/if/lwip/lwipNetUdpSocket.cpp	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,265 @@
+#pragma diag_remark 1464
+/*
+Copyright (c) 2010 Donatien Garnier (donatiengar [at] gmail [dot] com)
+ 
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+ 
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+ 
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+#include "lwip/ip_addr.h"
+#include "lwipNetUdpSocket.h"
+#include "lwip/udp.h"
+#include "lwip/igmp.h"
+
+
+//#define __DEBUG
+#include "dbg/dbg.h"
+
+#include "netCfg.h"
+#if NET_LWIP_STACK
+
+LwipNetUdpSocket::LwipNetUdpSocket(udp_pcb* pPcb /*= NULL*/) : NetUdpSocket(), m_pPcb(pPcb), m_lInPkt(), m_multicastGroup() //Passes a pcb if already created (by an accept req for instance), in that case transfers ownership
+{
+  DBG("New LwipNetUdpSocket %p (pPCb=%p)\n", (void*)this, (void*) pPcb);
+  if(!m_pPcb)
+    m_pPcb = udp_new();
+  if(m_pPcb)
+  {
+    //Setup callback
+    udp_recv( (udp_pcb*) m_pPcb, LwipNetUdpSocket::sRecvCb, (void*) this );
+  }
+}
+
+LwipNetUdpSocket::~LwipNetUdpSocket()
+{
+  close();
+}
+  
+NetUdpSocketErr LwipNetUdpSocket::bind(const Host& me)
+{
+  err_t err;
+  
+  if(!m_pPcb)
+    return NETUDPSOCKET_MEM; //NetUdpSocket was not properly initialised, should destroy it & retry
+   
+  #if LWIP_IGMP //Multicast support enabled
+  if(me.getIp().isMulticast())
+  {
+    DBG("This is a multicast addr, joining multicast group\n");
+    m_multicastGroup = me.getIp();
+    err = igmp_joingroup(IP_ADDR_ANY, &(m_multicastGroup.getStruct()));
+    if(err)
+      return NETUDPSOCKET_IF; //Could not find or create group
+  }
+  #endif
+
+  err = udp_bind( (udp_pcb*) m_pPcb, IP_ADDR_ANY, me.getPort()); //IP_ADDR_ANY : Bind the connection to all local addresses
+  if(err)
+    return NETUDPSOCKET_INUSE;
+
+  //Setup callback
+  udp_recv( (udp_pcb*) m_pPcb, LwipNetUdpSocket::sRecvCb, (void*) this );
+    
+  return NETUDPSOCKET_OK;
+}
+
+#define MAX(a,b) ((a>b)?a:b)
+#define MIN(a,b) ((a<b)?a:b)
+
+int /*if < 0 : NetUdpSocketErr*/ LwipNetUdpSocket::sendto(const char* buf, int len, Host* pHost)
+{
+  if( !m_pPcb ) //Pcb doesn't exist (anymore)
+    return NETUDPSOCKET_MEM;
+  pbuf* p = pbuf_alloc(PBUF_TRANSPORT, len, PBUF_POOL);
+  if( !p )
+    return NETUDPSOCKET_MEM;
+  char* pBuf = (char*) buf;
+  pbuf* q = p; 
+  do
+  {
+    memcpy (q->payload, (void*)pBuf, q->len);  
+    pBuf += q->len;
+    q = q->next;
+  } while(q != NULL);
+
+  err_t err = udp_sendto( (udp_pcb*) m_pPcb, p, &(pHost->getIp().getStruct()), pHost->getPort() );
+  pbuf_free( p );
+  if(err)
+    return NETUDPSOCKET_SETUP; //Connection problem
+  DBG("%d bytes sent in UDP Socket.\n", len);
+  return len;
+}
+
+int /*if < 0 : NetUdpSocketErr*/ LwipNetUdpSocket::recvfrom(char* buf, int len, Host* pHost)
+{
+  if( !m_pPcb ) //Pcb doesn't exist (anymore)
+    return NETUDPSOCKET_MEM;
+  int inLen = 0;
+  int cpyLen = 0;
+  
+  static int rmgLen = 0; 
+  //Contains the remaining len in this pbuf
+  
+  if( m_lInPkt.empty() )
+    return 0;
+    
+  pbuf* pBuf = (pbuf*) m_lInPkt.front().pBuf;
+  
+  if(pHost)
+    *pHost = Host( IpAddr(&m_lInPkt.front().addr), m_lInPkt.front().port );
+  
+  if( !pBuf )
+  {
+    rmgLen = 0;
+    return 0;
+  }
+  
+  if ( !rmgLen ) //We did not know m_pReadPbuf->len last time we called this fn
+  {
+    rmgLen = pBuf->len;
+  }
+  
+  while ( inLen < len )
+  {
+    cpyLen = MIN( (len - inLen), rmgLen ); //Remaining len to copy, remaining len in THIS pbuf
+    memcpy((void*)buf, (void*)((char*)(pBuf->payload) + (pBuf->len - rmgLen)), cpyLen);
+    inLen += cpyLen;
+    buf += cpyLen;
+    
+    rmgLen = rmgLen - cpyLen; //Update rmgLen
+    
+    if( rmgLen > 0 )
+    {
+      //We did not read this pbuf completely, so let's save it's pos & return
+      break;
+    }
+    
+    if(pBuf->next)
+    {
+      pbuf* pNextPBuf = pBuf->next;
+      pBuf->next = NULL; //So that it is not freed as well
+      //We get the reference to pNextPBuf from m_pReadPbuf
+      pbuf_free((pbuf*)pBuf);
+      pBuf = pNextPBuf;
+      rmgLen = pBuf->len;
+    }
+    else
+    {
+      pbuf_free((pbuf*)pBuf);
+      pBuf = NULL;
+      rmgLen = 0;
+      m_lInPkt.pop_front();
+      break; //No more data to read
+    } 
+  }
+  
+  return inLen;
+}
+
+NetUdpSocketErr LwipNetUdpSocket::close()
+{
+  DBG("LwipNetUdpSocket::close() : Closing...\n");
+
+  if(m_closed)
+    return NETUDPSOCKET_OK; //Already being closed
+  m_closed = true;
+  
+  if( !m_pPcb ) //Pcb doesn't exist (anymore)
+    return NETUDPSOCKET_MEM;
+    
+  DBG("LwipNetUdpSocket::close() : Cleanup...\n");
+    
+  //Cleanup incoming data
+  cleanUp();
+  
+
+  DBG("LwipNetUdpSocket::close() : removing m_pPcb...\n");
+  udp_remove( (udp_pcb*) m_pPcb);
+    
+  m_pPcb = NULL;
+  return NETUDPSOCKET_OK;
+}
+
+NetUdpSocketErr LwipNetUdpSocket::poll()
+{
+  NetUdpSocket::flushEvents();
+  return NETUDPSOCKET_OK;
+}
+
+// Callbacks events
+
+void LwipNetUdpSocket::recvCb(udp_pcb* pcb, struct pbuf* p, ip_addr_t* addr, u16_t port)
+{
+  DBG(" Packet of length %d arrived in UDP Socket.\n", p->tot_len);
+  list<InPacket>::iterator it;
+  for ( it = m_lInPkt.begin(); it != m_lInPkt.end(); it++ )
+  {
+    if( ip_addr_cmp((&((*it).addr)), addr) && ((*it).port == port) )
+    {
+      //Let's tail this packet to the previous one
+      pbuf_cat((pbuf*)((*it).pBuf), p);
+      //No need to queue an event in that case since the read buf has not been processed yet
+      return;
+    }
+  }
+
+  //New host, add a packet to the queue
+  InPacket pkt;
+  pkt.pBuf = p;
+  pkt.addr = *addr;
+  pkt.port = port;
+  m_lInPkt.push_back(pkt);
+  
+  queueEvent(NETUDPSOCKET_READABLE);
+}
+
+void LwipNetUdpSocket::cleanUp() //Flush input buffer
+{
+  //Ensure that further error won't be followed to this inst (which can be destroyed)
+  if( m_pPcb )
+  {
+    udp_recv( (udp_pcb*) m_pPcb, NULL, (void*) NULL );
+  }
+  
+  //Leaving multicast group(Ok because LwIP has a refscount for multicast group)
+  #if LWIP_IGMP //Multicast support enabled
+  if(m_multicastGroup.isMulticast())
+  {
+    igmp_leavegroup(IP_ADDR_ANY, &(m_multicastGroup.getStruct()));
+    m_multicastGroup = IpAddr();
+  }
+  #endif
+  
+  list<InPacket>::iterator it;
+  for ( it = m_lInPkt.begin(); it != m_lInPkt.end(); it++ )
+  {
+    //Free buf
+    pbuf_free((pbuf*)((*it).pBuf));
+  } 
+  m_lInPkt.clear();
+}
+
+// Static callback from LwIp
+
+void LwipNetUdpSocket::sRecvCb(void *arg, struct udp_pcb *pcb, struct pbuf *p, ip_addr_t *addr, u16_t port)
+{
+  LwipNetUdpSocket* pMe = (LwipNetUdpSocket*) arg;
+  return pMe->recvCb( pcb, p, addr, port );
+}
+
+#endif
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/if/lwip/lwipNetUdpSocket.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,84 @@
+
+/*
+Copyright (c) 2010 Donatien Garnier (donatiengar [at] gmail [dot] com)
+ 
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+ 
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+ 
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+#ifndef LWIPNETUDPSOCKET_H
+#define LWIPNETUDPSOCKET_H
+
+#define NET_LWIP_STACK 1
+//#include "lwip/ip_addr.h"
+#include "if/net/netudpsocket.h"
+#include "LwipNetIf.h"
+
+#include "stdint.h"
+
+#include <list>
+using std::list;
+
+//Implements NetUdpSockets over lwIP raw API
+
+struct udp_pcb; //Represents a Udp Connection, "Protocol Control Block", see rawapi.txt & udp.h
+struct pbuf; //Lwip Buffer Container
+typedef struct ip_addr ip_addr_t;
+
+//typedef signed char err_t;
+typedef uint16_t u16_t;
+
+class LwipNetUdpSocket: public NetUdpSocket
+{
+public:
+  LwipNetUdpSocket(udp_pcb* pPcb = NULL); //Passes a pcb if already created (by an accept req for instance), in that case transfers ownership
+  virtual ~LwipNetUdpSocket();
+  
+  virtual NetUdpSocketErr bind(const Host& me);
+  
+  virtual int /*if < 0 : NetUdpSocketErr*/ sendto(const char* buf, int len, Host* pHost);
+  virtual int /*if < 0 : NetUdpSocketErr*/ recvfrom(char* buf, int len, Host* pHost);
+
+  virtual NetUdpSocketErr close();
+
+  virtual NetUdpSocketErr poll();
+  
+protected:
+  volatile udp_pcb* m_pPcb;
+  
+  //Event callback from lwIp
+  void recvCb(udp_pcb* pcb, struct pbuf* p, ip_addr_t* addr, u16_t port);
+  
+private:
+  void cleanUp(); //Flush input buffer
+  struct InPacket
+  {
+    volatile pbuf* pBuf;
+    ip_addr_t addr;
+    u16_t port;
+  };
+  
+  list<InPacket> m_lInPkt;
+  IpAddr m_multicastGroup;
+  
+  //Static callback : Transforms into a C++ callback
+  static void sRecvCb(void *arg, struct udp_pcb *pcb, struct pbuf *p, ip_addr_t *addr, u16_t port);
+  
+};
+
+#endif
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/if/net/netdnsrequest.cpp	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,66 @@
+
+/*
+Copyright (c) 2010 Donatien Garnier (donatiengar [at] gmail [dot] com)
+ 
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+ 
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+ 
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+#include "netdnsrequest.h"
+#include <string.h>
+
+NetDnsRequest::NetDnsRequest(const char* hostname) : NetService(), m_ip(0,0,0,0), m_pCbItem(NULL), m_pCbMeth(NULL), m_pHost(NULL), m_closed(false)
+{
+  m_hostname = new char[strlen(hostname)+1];
+  strcpy( m_hostname, hostname );
+}
+
+NetDnsRequest::NetDnsRequest(Host* pHost)  : NetService(), m_ip(0,0,0,0), m_pCbItem(NULL), m_pCbMeth(NULL), m_closed(false)
+{
+  m_hostname = (char*) pHost->getName();
+  m_pHost = pHost;
+}
+
+NetDnsRequest::~NetDnsRequest()
+{
+  close();
+}
+   
+void NetDnsRequest::getResult(IpAddr* pIp)
+{
+  if( pIp != NULL )
+    *pIp = m_ip;
+}
+
+void NetDnsRequest::close()
+{
+  if(m_closed)
+    return;
+  m_closed = true;
+  if( !m_pHost )
+    delete[] m_hostname;
+  NetService::close();
+}
+  
+void NetDnsRequest::onReply(NetDnsReply reply) //Must be called by impl when the request completes
+{
+  if( m_pHost )
+    m_pHost->setIp(m_ip);
+  if(m_pCbItem && m_pCbMeth)
+    (m_pCbItem->*m_pCbMeth)(reply);
+}
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/if/net/netdnsrequest.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,84 @@
+
+/*
+Copyright (c) 2010 Donatien Garnier (donatiengar [at] gmail [dot] com)
+ 
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+ 
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+ 
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+#ifndef NETDNSREQUEST_H
+#define NETDNSREQUEST_H
+
+//class Socket;
+class Host;
+//class NetService;
+class NetDnsRequest;
+
+#include "netservice.h"
+#include "ipaddr.h"
+#include "host.h"
+
+enum NetDnsReply
+{
+  NETDNS_PRTCL,
+  NETDNS_NOTFOUND, //Hostname is unknown
+  NETDNS_ERROR, //Problem with DNS Service
+  //...
+  NETDNS_FOUND,
+};
+
+class NetDnsRequest : public NetService
+{
+public:
+  NetDnsRequest(const char* hostname);
+  NetDnsRequest(Host* pHost);
+  virtual ~NetDnsRequest();
+  
+  class CDummy;
+  template<class T> 
+  //Linker bug : Must be defined here :(
+  void setOnReply( T* pItem, void (T::*pMethod)(NetDnsReply) )
+  {
+    m_pCbItem = (CDummy*) pItem;
+    m_pCbMeth = (void (CDummy::*)(NetDnsReply)) pMethod;
+  }
+  
+  //Execute request & return OK if found, NOTFOUND or ERROR on error, or PROCESSING if the request has not completed yet
+ // virtual DnsErr pollState() = 0;
+  virtual void poll() = 0; //NetService fn
+  
+  void getResult(IpAddr* pIp);
+  
+  virtual void close();
+  
+protected:
+  void onReply(NetDnsReply reply); //Must be called by impl when the request completes
+  
+  IpAddr m_ip;
+  char* m_hostname;
+
+private:  
+  CDummy* m_pCbItem;
+  void (CDummy::*m_pCbMeth)(NetDnsReply);
+  
+  Host* m_pHost;
+  
+  bool m_closed;
+};
+
+#endif
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/if/net/netif.cpp	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,43 @@
+
+/*
+Copyright (c) 2010 Donatien Garnier (donatiengar [at] gmail [dot] com)
+ 
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+ 
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+ 
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+#include "core/host.h"
+#include "netif.h"
+#include "core/net.h"
+
+NetIf::NetIf() : m_ip(0,0,0,0)
+{
+  Net::registerIf(this);
+  //Assuming that we only have one if
+  Net::setDefaultIf(this);
+}
+
+NetIf::~NetIf()
+{
+  Net::unregisterIf(this);
+}
+
+IpAddr NetIf::getIp() const
+{
+  return m_ip;
+}
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/if/net/netif.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,64 @@
+
+/*
+Copyright (c) 2010 Donatien Garnier (donatiengar [at] gmail [dot] com)
+ 
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+ 
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+ 
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+#ifndef NETIF_H
+#define NETIF_H
+
+#include "core/ipaddr.h"
+/*
+#include "nettcpsocket.h"
+#include "netudpsocket.h"
+#include "netdnsrequest.h"
+*/
+class NetTcpSocket;
+class NetUdpSocket;
+class NetDnsRequest;
+
+#if 0
+enum NetifEvent
+{
+  NETIF_CONNECTED, //Connected, can create & use sockets now
+  NETIF_DNSREPLY,
+  NETIF_DISCONNECTED
+};
+#endif
+
+class NetIf
+{
+public:
+  NetIf();
+  virtual ~NetIf();
+  virtual NetTcpSocket* tcpSocket() = 0; //Create a new tcp socket
+  virtual NetUdpSocket* udpSocket() = 0; //Create a new udp socket
+  virtual void poll() = 0;
+  virtual NetDnsRequest* dnsRequest(const char* hostname) = 0; //Create a new NetDnsRequest object
+  virtual NetDnsRequest* dnsRequest(Host* pHost) = 0; //Create a new NetDnsRequest object
+  
+  //!Returns the IP of the interface once it's connected
+  IpAddr getIp() const;
+  
+protected:
+  IpAddr m_ip;
+};
+
+#endif
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/if/net/nettcpsocket.cpp	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,82 @@
+
+/*
+Copyright (c) 2010 Donatien Garnier (donatiengar [at] gmail [dot] com)
+ 
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+ 
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+ 
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+#include "nettcpsocket.h"
+
+//#define __DEBUG
+#include "dbg/dbg.h"
+
+NetTcpSocket::NetTcpSocket() : m_host(), m_client(), m_refs(0), m_closed(false), m_removed(false), m_pCbItem(NULL), m_pCbMeth(NULL), m_events()
+{
+  Net::registerNetTcpSocket(this);
+}
+
+NetTcpSocket::~NetTcpSocket() //close()
+{
+  Net::unregisterNetTcpSocket(this);
+}
+  
+   
+//Callbacks
+#ifdef __LINKER_BUG_SOLVED__
+void NetTcpSocket::setOnEvent()
+{
+  m_pCbItem = (CDummy*) pItem;
+  m_pCbMeth = (void (CDummy::*)(NetTcpSocketEvent)) pMethod;
+}
+#endif
+
+void NetTcpSocket::resetOnEvent()
+{
+  m_pCbItem = NULL;
+  m_pCbMeth = NULL;
+}
+
+void NetTcpSocket::queueEvent(NetTcpSocketEvent e)
+{
+  m_events.push(e);
+}
+
+void NetTcpSocket::discardEvents()
+{
+  while( !m_events.empty() )
+  {
+    m_events.pop();
+  }
+}
+
+void NetTcpSocket::flushEvents() //To be called during polling
+{ 
+  while( !m_events.empty() )
+  {
+    onEvent(m_events.front());
+    m_events.pop();
+  }
+}
+
+void NetTcpSocket::onEvent(NetTcpSocketEvent e) //To be called during polling
+{
+  if(m_pCbItem && m_pCbMeth)
+    (m_pCbItem->*m_pCbMeth)(e);
+}
+
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/if/net/nettcpsocket.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,118 @@
+
+/*
+Copyright (c) 2010 Donatien Garnier (donatiengar [at] gmail [dot] com)
+ 
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+ 
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+ 
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+#ifndef NETTCPSOCKET_H
+#define NETTCPSOCKET_H
+
+#include "net.h"
+#include "host.h"
+
+#include <queue>
+using std::queue;
+
+//Implements a Berkeley-like socket if
+//Can be interfaced either to lwip or a Telit module
+
+enum NetTcpSocketErr
+{
+  __NETTCPSOCKET_MIN = -0xFFFF,
+  NETTCPSOCKET_SETUP, //NetTcpSocket not properly configured
+  NETTCPSOCKET_TIMEOUT,
+  NETTCPSOCKET_IF, //If has problems
+  NETTCPSOCKET_MEM, //Not enough mem
+  NETTCPSOCKET_INUSE, //If/Port is in use
+  NETTCPSOCKET_EMPTY, //Connections queue is empty
+  NETTCPSOCKET_RST, // Connection was reset by remote host
+//...
+  NETTCPSOCKET_OK = 0
+};
+
+enum NetTcpSocketEvent
+{
+  NETTCPSOCKET_CONNECTED, //Connected to host, must call accept() if we were listening
+  NETTCPSOCKET_ACCEPT,  //Connected to client
+  NETTCPSOCKET_READABLE, //Data in buf
+  NETTCPSOCKET_WRITEABLE, //Can write data to buf
+  NETTCPSOCKET_CONTIMEOUT,
+  NETTCPSOCKET_CONRST,
+  NETTCPSOCKET_CONABRT,
+  NETTCPSOCKET_ERROR,
+  NETTCPSOCKET_DISCONNECTED
+};
+
+
+class NetTcpSocket
+{
+public:
+  NetTcpSocket();
+  virtual ~NetTcpSocket(); //close()
+  
+  virtual NetTcpSocketErr bind(const Host& me) = 0;
+  virtual NetTcpSocketErr listen() = 0;
+  virtual NetTcpSocketErr connect(const Host& host) = 0;
+  virtual NetTcpSocketErr accept(Host* pClient, NetTcpSocket** ppNewNetTcpSocket) = 0;
+  
+  virtual int /*if < 0 : NetTcpSocketErr*/ send(const char* buf, int len) = 0;
+  virtual int /*if < 0 : NetTcpSocketErr*/ recv(char* buf, int len) = 0;
+
+  virtual NetTcpSocketErr close() = 0;
+
+  virtual NetTcpSocketErr poll() = 0;
+  
+  class CDummy;
+  //Callbacks
+  template<class T> 
+  //Linker bug : Must be defined here :(
+  void setOnEvent( T* pItem, void (T::*pMethod)(NetTcpSocketEvent) )
+  {
+    m_pCbItem = (CDummy*) pItem;
+    m_pCbMeth = (void (CDummy::*)(NetTcpSocketEvent)) pMethod;
+  }
+  
+  void resetOnEvent(); //Disable callback
+
+protected:
+  void queueEvent(NetTcpSocketEvent e);
+  void discardEvents();  
+  void flushEvents(); //to be called during polling
+
+  Host m_host;
+  Host m_client;
+  
+  friend class Net;
+  int m_refs;
+
+  bool m_closed;
+  bool m_removed;
+  
+private:
+  //We do not want to execute user code in interrupt routines, so we queue events until the server is polled
+  //If we port this to a multithreaded OS, we could avoid this (however some functions here are not thread-safe, so beware ;) )
+  void onEvent(NetTcpSocketEvent e); //To be called on poll
+  CDummy* m_pCbItem;
+  void (CDummy::*m_pCbMeth)(NetTcpSocketEvent);
+  queue<NetTcpSocketEvent> m_events;
+
+};
+
+#endif
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/if/net/netudpsocket.cpp	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,82 @@
+
+/*
+Copyright (c) 2010 Donatien Garnier (donatiengar [at] gmail [dot] com)
+ 
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+ 
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+ 
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+#include "netudpsocket.h"
+
+//#define __DEBUG
+#include "dbg/dbg.h"
+
+NetUdpSocket::NetUdpSocket() : m_host(), m_client(), m_refs(0), m_closed(false), m_removed(false), m_pCbItem(NULL), m_pCbMeth(NULL), m_events()
+{
+  Net::registerNetUdpSocket(this);
+}
+
+NetUdpSocket::~NetUdpSocket() //close()
+{
+  Net::unregisterNetUdpSocket(this);
+}
+  
+   
+//Callbacks
+#if 0 //Just for info
+void NetUdpSocket::setOnEvent()
+{
+  m_pCbItem = (CDummy*) pItem;
+  m_pCbMeth = (void (CDummy::*)(NetUdpSocketEvent)) pMethod;
+}
+#endif
+
+void NetUdpSocket::resetOnEvent()
+{
+  m_pCbItem = NULL;
+  m_pCbMeth = NULL;
+}
+
+void NetUdpSocket::queueEvent(NetUdpSocketEvent e)
+{
+  m_events.push(e);
+}
+
+void NetUdpSocket::discardEvents()
+{
+  while( !m_events.empty() )
+  {
+    m_events.pop();
+  }
+}
+
+void NetUdpSocket::flushEvents() //To be called during polling
+{ 
+  while( !m_events.empty() )
+  {
+    onEvent(m_events.front());
+    m_events.pop();
+  }
+}
+
+void NetUdpSocket::onEvent(NetUdpSocketEvent e) //To be called during polling
+{
+  if(m_pCbItem && m_pCbMeth)
+    (m_pCbItem->*m_pCbMeth)(e);
+}
+
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/if/net/netudpsocket.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,106 @@
+
+/*
+Copyright (c) 2010 Donatien Garnier (donatiengar [at] gmail [dot] com)
+ 
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+ 
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+ 
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+#ifndef NETUDPSOCKET_H
+#define NETUDPSOCKET_H
+
+#include "net.h"
+#include "host.h"
+
+#include <queue>
+using std::queue;
+
+//Implements a Berkeley-like socket if
+//Can be interfaced either to lwip or a Telit module
+
+enum NetUdpSocketErr
+{
+  __NETUDPSOCKET_MIN = -0xFFFF,
+  NETUDPSOCKET_SETUP, //NetUdpSocket not properly configured
+  NETUDPSOCKET_IF, //If has problems
+  NETUDPSOCKET_MEM, //Not enough mem
+  NETUDPSOCKET_INUSE, //If/Port is in use
+//...
+  NETUDPSOCKET_OK = 0
+};
+
+enum NetUdpSocketEvent //Only one lonely event here... but who knows, maybe some day there'll be another one!
+{
+  NETUDPSOCKET_READABLE, //Data in buf
+};
+
+
+class NetUdpSocket
+{
+public:
+  NetUdpSocket();
+  virtual ~NetUdpSocket(); //close()
+  
+  virtual NetUdpSocketErr bind(const Host& me) = 0;
+  
+  virtual int /*if < 0 : NetUdpSocketErr*/ sendto(const char* buf, int len, Host* pHost) = 0;
+  virtual int /*if < 0 : NetUdpSocketErr*/ recvfrom(char* buf, int len, Host* pHost) = 0;
+
+  /* TODO NTH : printf / scanf helpers that call send/recv */
+
+  virtual NetUdpSocketErr close() = 0;
+
+  virtual NetUdpSocketErr poll() = 0;
+  
+  class CDummy;
+  //Callbacks
+  template<class T> 
+  //Linker bug : Must be defined here :(
+  void setOnEvent( T* pItem, void (T::*pMethod)(NetUdpSocketEvent) )
+  {
+    m_pCbItem = (CDummy*) pItem;
+    m_pCbMeth = (void (CDummy::*)(NetUdpSocketEvent)) pMethod;
+  }
+  
+  void resetOnEvent(); //Disable callback
+
+protected:
+  void queueEvent(NetUdpSocketEvent e);
+  void discardEvents();  
+  void flushEvents(); //to be called during polling
+
+  Host m_host;
+  Host m_client;
+  
+  friend class Net;
+  int m_refs;
+
+  bool m_closed;
+  bool m_removed;
+  
+private:
+  //We do not want to execute user code in interrupt routines, so we queue events until the server is polled
+  //If we port this to a multithreaded OS, we could avoid this (however some functions here are not thread-safe, so beware ;) )
+  void onEvent(NetUdpSocketEvent e); //To be called on poll
+  CDummy* m_pCbItem;
+  void (CDummy::*m_pCbMeth)(NetUdpSocketEvent);
+  queue<NetUdpSocketEvent> m_events;
+
+};
+
+#endif
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/arch/cc.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,62 @@
+/*
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+#ifndef __LWIP_ARCH_CC_H__
+#define __LWIP_ARCH_CC_H__
+
+#define LITTLE_ENDIAN 1234
+
+#define BYTE_ORDER  LITTLE_ENDIAN
+
+typedef unsigned char   u8_t;
+typedef signed char     s8_t;
+typedef unsigned short  u16_t;
+typedef signed short    s16_t;
+typedef unsigned int    u32_t;
+typedef signed int      s32_t;
+typedef unsigned int    mem_ptr_t;
+
+#ifndef NULL
+#define NULL 0
+#endif
+
+#ifndef TRUE
+#define TRUE 1
+#endif
+
+#ifndef FALSE
+#define FALSE 0
+#endif
+
+#include <stdlib.h>
+#define LWIP_RAND rand
+
+#define LWIP_PLATFORM_DIAG(x) DBG x
+#define LWIP_PLATFORM_ASSERT(x) DBG(x)
+
+#define LWIP_PROVIDE_ERRNO
+
+#define U16_F "hu"
+#define S16_F "hd"
+#define X16_F "hx"
+#define U32_F "lu"
+#define S32_F "ld"
+#define X32_F "lx"
+
+#if 0 
+/*Create compilation problems, and according to http://www.mail-archive.com/lwip-users@nongnu.org/msg06786.html, 
+lwIP uses packed structures, so packing the field is not really a good idea ;) */
+#define PACK_STRUCT_FIELD(x) __packed x
+#else 
+#define PACK_STRUCT_FIELD(x)    x
+#endif
+
+#define PACK_STRUCT_STRUCT
+#define PACK_STRUCT_BEGIN __packed
+#define PACK_STRUCT_END
+
+#define LWIP_CHKSUM_ALGORITHM 3
+
+
+#endif /* __LWIP_ARCH_CC_H__ */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/arch/perf.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,23 @@
+/*
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+#ifndef __LWIP_ARCH_PERF_H__
+#define __LWIP_ARCH_PERF_H__
+
+#define PERF_START
+#define PERF_STOP(x)
+
+#define perf_init(fname)
+
+#if 0
+#ifdef __cplusplus
+inline
+#endif
+void perf_init(char *fname) {
+  return;  
+}
+#endif
+
+
+#endif /* __LWIP_ARCH_PERF_H__ */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/arch/sys_arch.cpp	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,70 @@
+#include "sys_arch.h"
+#include "mbed.h"
+//DG 2010
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#ifdef __COMPLEX_AND_BUGGUY_HANDLING__
+static Timer* pTmr = NULL;
+
+void sys_init(void)
+{
+  //Start Timer
+  pTmr = new Timer();
+  pTmr->start();
+}
+
+u32_t sys_jiffies(void) /* since power up. */
+{
+  return (u32_t) (pTmr->read_ms()/10); //In /10ms units
+}
+
+u32_t sys_now(void)
+{
+  return (u32_t) pTmr->read_ms(); //In /ms units
+}
+#elif0
+void sys_init(void)
+{
+
+}
+
+u32_t sys_jiffies(void) /* since power up. */
+{
+  static int count = 0;
+  return ++count;
+}
+
+u32_t sys_now(void)
+{
+  return (u32_t) time(NULL);
+}
+#else
+static Timer* pTmr = NULL;
+
+void sys_init(void)
+{
+  //Start Timer
+  pTmr = new Timer();
+  pTmr->start();
+}
+
+u32_t sys_jiffies(void) /* since power up. */
+{
+  static int count = 0;
+  return ++count;
+  //return (u32_t) (pTmr->read_us());
+}
+
+u32_t sys_now(void)
+{
+  return (u32_t) (pTmr->read_ms()); //In /ms units
+}
+#endif
+
+
+#ifdef __cplusplus
+}
+#endif
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/arch/sys_arch.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,27 @@
+/*
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+#ifndef __LWIP_SYS_ARCH_H__
+#define __LWIP_SYS_ARCH_H__
+
+typedef unsigned int u32_t;
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+//DG 2010
+void sys_init(void); /* To be called first */
+u32_t sys_jiffies(void); /* since power up. */
+
+/** Returns the current time in milliseconds,
+ * may be the same as sys_jiffies or at least based on it. */
+u32_t sys_now(void);
+
+#ifdef __cplusplus
+}
+#endif
+
+
+#endif /* __LWIP_ARCH_CC_H__ */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/core/def.c	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,108 @@
+/**
+ * @file
+ * Common functions used throughout the stack.
+ *
+ */
+
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ *
+ * Author: Simon Goldschmidt
+ *
+ */
+
+#include "lwip/opt.h"
+#include "lwip/def.h"
+
+/**
+ * These are reference implementations of the byte swapping functions.
+ * Again with the aim of being simple, correct and fully portable.
+ * Byte swapping is the second thing you would want to optimize. You will
+ * need to port it to your architecture and in your cc.h:
+ * 
+ * #define LWIP_PLATFORM_BYTESWAP 1
+ * #define LWIP_PLATFORM_HTONS(x) <your_htons>
+ * #define LWIP_PLATFORM_HTONL(x) <your_htonl>
+ *
+ * Note ntohs() and ntohl() are merely references to the htonx counterparts.
+ */
+
+#if (LWIP_PLATFORM_BYTESWAP == 0) && (BYTE_ORDER == LITTLE_ENDIAN)
+
+/**
+ * Convert an u16_t from host- to network byte order.
+ *
+ * @param n u16_t in host byte order
+ * @return n in network byte order
+ */
+u16_t
+lwip_htons(u16_t n)
+{
+  return ((n & 0xff) << 8) | ((n & 0xff00) >> 8);
+}
+
+/**
+ * Convert an u16_t from network- to host byte order.
+ *
+ * @param n u16_t in network byte order
+ * @return n in host byte order
+ */
+u16_t
+lwip_ntohs(u16_t n)
+{
+  return lwip_htons(n);
+}
+
+/**
+ * Convert an u32_t from host- to network byte order.
+ *
+ * @param n u32_t in host byte order
+ * @return n in network byte order
+ */
+u32_t
+lwip_htonl(u32_t n)
+{
+  return ((n & 0xff) << 24) |
+    ((n & 0xff00) << 8) |
+    ((n & 0xff0000UL) >> 8) |
+    ((n & 0xff000000UL) >> 24);
+}
+
+/**
+ * Convert an u32_t from network- to host byte order.
+ *
+ * @param n u32_t in network byte order
+ * @return n in host byte order
+ */
+u32_t
+lwip_ntohl(u32_t n)
+{
+  return lwip_htonl(n);
+}
+
+#endif /* (LWIP_PLATFORM_BYTESWAP == 0) && (BYTE_ORDER == LITTLE_ENDIAN) */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/core/dhcp.c	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,1725 @@
+/**
+ * @file
+ * Dynamic Host Configuration Protocol client
+ *
+ */
+
+/*
+ *
+ * Copyright (c) 2001-2004 Leon Woestenberg <leon.woestenberg@gmx.net>
+ * Copyright (c) 2001-2004 Axon Digital Design B.V., The Netherlands.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * This file is a contribution to the lwIP TCP/IP stack.
+ * The Swedish Institute of Computer Science and Adam Dunkels
+ * are specifically granted permission to redistribute this
+ * source code.
+ *
+ * Author: Leon Woestenberg <leon.woestenberg@gmx.net>
+ *
+ * This is a DHCP client for the lwIP TCP/IP stack. It aims to conform
+ * with RFC 2131 and RFC 2132.
+ *
+ * TODO:
+ * - Support for interfaces other than Ethernet (SLIP, PPP, ...)
+ *
+ * Please coordinate changes and requests with Leon Woestenberg
+ * <leon.woestenberg@gmx.net>
+ *
+ * Integration with your code:
+ *
+ * In lwip/dhcp.h
+ * #define DHCP_COARSE_TIMER_SECS (recommended 60 which is a minute)
+ * #define DHCP_FINE_TIMER_MSECS (recommended 500 which equals TCP coarse timer)
+ *
+ * Then have your application call dhcp_coarse_tmr() and
+ * dhcp_fine_tmr() on the defined intervals.
+ *
+ * dhcp_start(struct netif *netif);
+ * starts a DHCP client instance which configures the interface by
+ * obtaining an IP address lease and maintaining it.
+ *
+ * Use dhcp_release(netif) to end the lease and use dhcp_stop(netif)
+ * to remove the DHCP client.
+ *
+ */
+
+#include "lwip/opt.h"
+
+#if LWIP_DHCP /* don't build if not configured for use in lwipopts.h */
+
+#include "lwip/stats.h"
+#include "lwip/mem.h"
+#include "lwip/udp.h"
+#include "lwip/ip_addr.h"
+#include "lwip/netif.h"
+#include "lwip/def.h"
+#include "lwip/sys.h"
+#include "lwip/dhcp.h"
+#include "lwip/autoip.h"
+#include "lwip/dns.h"
+#include "netif/etharp.h"
+
+#include <string.h>
+
+/** Default for DHCP_GLOBAL_XID is 0xABCD0000
+ * This can be changed by defining DHCP_GLOBAL_XID and DHCP_GLOBAL_XID_HEADER, e.g.
+ *  #define DHCP_GLOBAL_XID_HEADER "stdlib.h"
+ *  #define DHCP_GLOBAL_XID rand()
+ */
+#ifdef DHCP_GLOBAL_XID_HEADER
+#include DHCP_GLOBAL_XID_HEADER /* include optional starting XID generation prototypes */
+#endif
+
+/** DHCP_OPTION_MAX_MSG_SIZE is set to the MTU
+ * MTU is checked to be big enough in dhcp_start */
+#define DHCP_MAX_MSG_LEN(netif)        (netif->mtu)
+#define DHCP_MAX_MSG_LEN_MIN_REQUIRED  576
+/** Minimum length for reply before packet is parsed */
+#define DHCP_MIN_REPLY_LEN             44
+
+#define REBOOT_TRIES 2
+
+/** Option handling: options are parsed in dhcp_parse_reply
+ * and saved in an array where other functions can load them from.
+ * This might be moved into the struct dhcp (not necessarily since
+ * lwIP is single-threaded and the array is only used while in recv
+ * callback). */
+#define DHCP_OPTION_IDX_OVERLOAD    0
+#define DHCP_OPTION_IDX_MSG_TYPE    1
+#define DHCP_OPTION_IDX_SERVER_ID   2
+#define DHCP_OPTION_IDX_LEASE_TIME  3
+#define DHCP_OPTION_IDX_T1          4
+#define DHCP_OPTION_IDX_T2          5
+#define DHCP_OPTION_IDX_SUBNET_MASK 6
+#define DHCP_OPTION_IDX_ROUTER      7
+#define DHCP_OPTION_IDX_DNS_SERVER	8
+#define DHCP_OPTION_IDX_MAX         (DHCP_OPTION_IDX_DNS_SERVER + DNS_MAX_SERVERS)
+
+/** Holds the decoded option values, only valid while in dhcp_recv.
+    @todo: move this into struct dhcp? */
+u32_t dhcp_rx_options_val[DHCP_OPTION_IDX_MAX];
+/** Holds a flag which option was received and is contained in dhcp_rx_options_val,
+    only valid while in dhcp_recv.
+    @todo: move this into struct dhcp? */
+u8_t  dhcp_rx_options_given[DHCP_OPTION_IDX_MAX];
+
+#define dhcp_option_given(dhcp, idx)          (dhcp_rx_options_given[idx] != 0)
+#define dhcp_got_option(dhcp, idx)            (dhcp_rx_options_given[idx] = 1)
+#define dhcp_clear_option(dhcp, idx)          (dhcp_rx_options_given[idx] = 0)
+#define dhcp_clear_all_options(dhcp)          (memset(dhcp_rx_options_given, 0, sizeof(dhcp_rx_options_given)))
+#define dhcp_get_option_value(dhcp, idx)      (dhcp_rx_options_val[idx])
+#define dhcp_set_option_value(dhcp, idx, val) (dhcp_rx_options_val[idx] = (val))
+
+
+/* DHCP client state machine functions */
+static err_t dhcp_discover(struct netif *netif);
+static err_t dhcp_select(struct netif *netif);
+static void dhcp_bind(struct netif *netif);
+#if DHCP_DOES_ARP_CHECK
+static err_t dhcp_decline(struct netif *netif);
+#endif /* DHCP_DOES_ARP_CHECK */
+static err_t dhcp_rebind(struct netif *netif);
+static err_t dhcp_reboot(struct netif *netif);
+static void dhcp_set_state(struct dhcp *dhcp, u8_t new_state);
+
+/* receive, unfold, parse and free incoming messages */
+static void dhcp_recv(void *arg, struct udp_pcb *pcb, struct pbuf *p, ip_addr_t *addr, u16_t port);
+
+/* set the DHCP timers */
+static void dhcp_timeout(struct netif *netif);
+static void dhcp_t1_timeout(struct netif *netif);
+static void dhcp_t2_timeout(struct netif *netif);
+
+/* build outgoing messages */
+/* create a DHCP message, fill in common headers */
+static err_t dhcp_create_msg(struct netif *netif, struct dhcp *dhcp, u8_t message_type);
+/* free a DHCP request */
+static void dhcp_delete_msg(struct dhcp *dhcp);
+/* add a DHCP option (type, then length in bytes) */
+static void dhcp_option(struct dhcp *dhcp, u8_t option_type, u8_t option_len);
+/* add option values */
+static void dhcp_option_byte(struct dhcp *dhcp, u8_t value);
+static void dhcp_option_short(struct dhcp *dhcp, u16_t value);
+static void dhcp_option_long(struct dhcp *dhcp, u32_t value);
+/* always add the DHCP options trailer to end and pad */
+static void dhcp_option_trailer(struct dhcp *dhcp);
+
+/**
+ * Back-off the DHCP client (because of a received NAK response).
+ *
+ * Back-off the DHCP client because of a received NAK. Receiving a
+ * NAK means the client asked for something non-sensible, for
+ * example when it tries to renew a lease obtained on another network.
+ *
+ * We clear any existing set IP address and restart DHCP negotiation
+ * afresh (as per RFC2131 3.2.3).
+ *
+ * @param netif the netif under DHCP control
+ */
+static void
+dhcp_handle_nak(struct netif *netif)
+{
+  struct dhcp *dhcp = netif->dhcp;
+  LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_handle_nak(netif=%p) %c%c%"U16_F"\n", 
+    (void*)netif, netif->name[0], netif->name[1], (u16_t)netif->num));
+  /* Set the interface down since the address must no longer be used, as per RFC2131 */
+  netif_set_down(netif);
+  /* remove IP address from interface */
+  netif_set_ipaddr(netif, IP_ADDR_ANY);
+  netif_set_gw(netif, IP_ADDR_ANY);
+  netif_set_netmask(netif, IP_ADDR_ANY); 
+  /* Change to a defined state */
+  dhcp_set_state(dhcp, DHCP_BACKING_OFF);
+  /* We can immediately restart discovery */
+  dhcp_discover(netif);
+}
+
+#if DHCP_DOES_ARP_CHECK
+/**
+ * Checks if the offered IP address is already in use.
+ *
+ * It does so by sending an ARP request for the offered address and
+ * entering CHECKING state. If no ARP reply is received within a small
+ * interval, the address is assumed to be free for use by us.
+ *
+ * @param netif the netif under DHCP control
+ */
+static void
+dhcp_check(struct netif *netif)
+{
+  struct dhcp *dhcp = netif->dhcp;
+  err_t result;
+  u16_t msecs;
+  LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_check(netif=%p) %c%c\n", (void *)netif, (s16_t)netif->name[0],
+    (s16_t)netif->name[1]));
+  dhcp_set_state(dhcp, DHCP_CHECKING);
+  /* create an ARP query for the offered IP address, expecting that no host
+     responds, as the IP address should not be in use. */
+  result = etharp_query(netif, &dhcp->offered_ip_addr, NULL);
+  if (result != ERR_OK) {
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_WARNING, ("dhcp_check: could not perform ARP query\n"));
+  }
+  dhcp->tries++;
+  msecs = 500;
+  dhcp->request_timeout = (msecs + DHCP_FINE_TIMER_MSECS - 1) / DHCP_FINE_TIMER_MSECS;
+  LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_check(): set request timeout %"U16_F" msecs\n", msecs));
+}
+#endif /* DHCP_DOES_ARP_CHECK */
+
+/**
+ * Remember the configuration offered by a DHCP server.
+ *
+ * @param netif the netif under DHCP control
+ */
+static void
+dhcp_handle_offer(struct netif *netif)
+{
+  struct dhcp *dhcp = netif->dhcp;
+  LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_handle_offer(netif=%p) %c%c%"U16_F"\n",
+    (void*)netif, netif->name[0], netif->name[1], (u16_t)netif->num));
+  /* obtain the server address */
+  if (dhcp_option_given(dhcp, DHCP_OPTION_IDX_SERVER_ID)) {
+    ip4_addr_set_u32(&dhcp->server_ip_addr, htonl(dhcp_get_option_value(dhcp, DHCP_OPTION_IDX_SERVER_ID)));
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_STATE, ("dhcp_handle_offer(): server 0x%08"X32_F"\n",
+      ip4_addr_get_u32(&dhcp->server_ip_addr)));
+    /* remember offered address */
+    ip_addr_copy(dhcp->offered_ip_addr, dhcp->msg_in->yiaddr);
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_STATE, ("dhcp_handle_offer(): offer for 0x%08"X32_F"\n",
+      ip4_addr_get_u32(&dhcp->offered_ip_addr)));
+
+    dhcp_select(netif);
+  } else {
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_SERIOUS,
+      ("dhcp_handle_offer(netif=%p) did not get server ID!\n", (void*)netif));
+  }
+}
+
+/**
+ * Select a DHCP server offer out of all offers.
+ *
+ * Simply select the first offer received.
+ *
+ * @param netif the netif under DHCP control
+ * @return lwIP specific error (see error.h)
+ */
+static err_t
+dhcp_select(struct netif *netif)
+{
+  struct dhcp *dhcp = netif->dhcp;
+  err_t result;
+  u16_t msecs;
+
+  LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_select(netif=%p) %c%c%"U16_F"\n", (void*)netif, netif->name[0], netif->name[1], (u16_t)netif->num));
+  dhcp_set_state(dhcp, DHCP_REQUESTING);
+
+  /* create and initialize the DHCP message header */
+  result = dhcp_create_msg(netif, dhcp, DHCP_REQUEST);
+  if (result == ERR_OK) {
+    dhcp_option(dhcp, DHCP_OPTION_MAX_MSG_SIZE, DHCP_OPTION_MAX_MSG_SIZE_LEN);
+    dhcp_option_short(dhcp, DHCP_MAX_MSG_LEN(netif));
+
+    /* MUST request the offered IP address */
+    dhcp_option(dhcp, DHCP_OPTION_REQUESTED_IP, 4);
+    dhcp_option_long(dhcp, ntohl(ip4_addr_get_u32(&dhcp->offered_ip_addr)));
+
+    dhcp_option(dhcp, DHCP_OPTION_SERVER_ID, 4);
+    dhcp_option_long(dhcp, ntohl(ip4_addr_get_u32(&dhcp->server_ip_addr)));
+
+    dhcp_option(dhcp, DHCP_OPTION_PARAMETER_REQUEST_LIST, 4/*num options*/);
+    dhcp_option_byte(dhcp, DHCP_OPTION_SUBNET_MASK);
+    dhcp_option_byte(dhcp, DHCP_OPTION_ROUTER);
+    dhcp_option_byte(dhcp, DHCP_OPTION_BROADCAST);
+    dhcp_option_byte(dhcp, DHCP_OPTION_DNS_SERVER);
+
+#if LWIP_NETIF_HOSTNAME
+    if (netif->hostname != NULL) {
+      const char *p = (const char*)netif->hostname;
+      u8_t namelen = (u8_t)strlen(p);
+      if (namelen > 0) {
+        LWIP_ASSERT("DHCP: hostname is too long!", namelen < 255);
+        dhcp_option(dhcp, DHCP_OPTION_HOSTNAME, namelen);
+        while (*p) {
+          dhcp_option_byte(dhcp, *p++);
+        }
+      }
+    }
+#endif /* LWIP_NETIF_HOSTNAME */
+
+    dhcp_option_trailer(dhcp);
+    /* shrink the pbuf to the actual content length */
+    pbuf_realloc(dhcp->p_out, sizeof(struct dhcp_msg) - DHCP_OPTIONS_LEN + dhcp->options_out_len);
+
+    /* send broadcast to any DHCP server */
+    udp_sendto_if(dhcp->pcb, dhcp->p_out, IP_ADDR_BROADCAST, DHCP_SERVER_PORT, netif);
+    dhcp_delete_msg(dhcp);
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_select: REQUESTING\n"));
+  } else {
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_WARNING, ("dhcp_select: could not allocate DHCP request\n"));
+  }
+  dhcp->tries++;
+  msecs = (dhcp->tries < 6 ? 1 << dhcp->tries : 60) * 1000;
+  dhcp->request_timeout = (msecs + DHCP_FINE_TIMER_MSECS - 1) / DHCP_FINE_TIMER_MSECS;
+  LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_STATE, ("dhcp_select(): set request timeout %"U16_F" msecs\n", msecs));
+  return result;
+}
+
+/**
+ * The DHCP timer that checks for lease renewal/rebind timeouts.
+ */
+void
+dhcp_coarse_tmr()
+{
+  struct netif *netif = netif_list;
+  LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_coarse_tmr()\n"));
+  /* iterate through all network interfaces */
+  while (netif != NULL) {
+    /* only act on DHCP configured interfaces */
+    if (netif->dhcp != NULL) {
+      /* timer is active (non zero), and triggers (zeroes) now? */
+      if (netif->dhcp->t2_timeout-- == 1) {
+        LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_coarse_tmr(): t2 timeout\n"));
+        /* this clients' rebind timeout triggered */
+        dhcp_t2_timeout(netif);
+      /* timer is active (non zero), and triggers (zeroes) now */
+      } else if (netif->dhcp->t1_timeout-- == 1) {
+        LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_coarse_tmr(): t1 timeout\n"));
+        /* this clients' renewal timeout triggered */
+        dhcp_t1_timeout(netif);
+      }
+    }
+    /* proceed to next netif */
+    netif = netif->next;
+  }
+}
+
+/**
+ * DHCP transaction timeout handling
+ *
+ * A DHCP server is expected to respond within a short period of time.
+ * This timer checks whether an outstanding DHCP request is timed out.
+ */
+void
+dhcp_fine_tmr()
+{
+  struct netif *netif = netif_list;
+  /* loop through netif's */
+  while (netif != NULL) {
+    /* only act on DHCP configured interfaces */
+    if (netif->dhcp != NULL) {
+      /* timer is active (non zero), and is about to trigger now */      
+      if (netif->dhcp->request_timeout > 1) {
+        netif->dhcp->request_timeout--;
+      }
+      else if (netif->dhcp->request_timeout == 1) {
+        netif->dhcp->request_timeout--;
+        /* { netif->dhcp->request_timeout == 0 } */
+        LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_fine_tmr(): request timeout\n"));
+        /* this client's request timeout triggered */
+        dhcp_timeout(netif);
+      }
+    }
+    /* proceed to next network interface */
+    netif = netif->next;
+  }
+}
+
+/**
+ * A DHCP negotiation transaction, or ARP request, has timed out.
+ *
+ * The timer that was started with the DHCP or ARP request has
+ * timed out, indicating no response was received in time.
+ *
+ * @param netif the netif under DHCP control
+ */
+static void
+dhcp_timeout(struct netif *netif)
+{
+  struct dhcp *dhcp = netif->dhcp;
+  LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_timeout()\n"));
+  /* back-off period has passed, or server selection timed out */
+  if ((dhcp->state == DHCP_BACKING_OFF) || (dhcp->state == DHCP_SELECTING)) {
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_timeout(): restarting discovery\n"));
+    dhcp_discover(netif);
+  /* receiving the requested lease timed out */
+  } else if (dhcp->state == DHCP_REQUESTING) {
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_timeout(): REQUESTING, DHCP request timed out\n"));
+    if (dhcp->tries <= 5) {
+      dhcp_select(netif);
+    } else {
+      LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_timeout(): REQUESTING, releasing, restarting\n"));
+      dhcp_release(netif);
+      dhcp_discover(netif);
+    }
+#if DHCP_DOES_ARP_CHECK
+  /* received no ARP reply for the offered address (which is good) */
+  } else if (dhcp->state == DHCP_CHECKING) {
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_timeout(): CHECKING, ARP request timed out\n"));
+    if (dhcp->tries <= 1) {
+      dhcp_check(netif);
+    /* no ARP replies on the offered address,
+       looks like the IP address is indeed free */
+    } else {
+      /* bind the interface to the offered address */
+      dhcp_bind(netif);
+    }
+#endif /* DHCP_DOES_ARP_CHECK */
+  }
+  /* did not get response to renew request? */
+  else if (dhcp->state == DHCP_RENEWING) {
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_timeout(): RENEWING, DHCP request timed out\n"));
+    /* just retry renewal */
+    /* note that the rebind timer will eventually time-out if renew does not work */
+    dhcp_renew(netif);
+  /* did not get response to rebind request? */
+  } else if (dhcp->state == DHCP_REBINDING) {
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_timeout(): REBINDING, DHCP request timed out\n"));
+    if (dhcp->tries <= 8) {
+      dhcp_rebind(netif);
+    } else {
+      LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_timeout(): RELEASING, DISCOVERING\n"));
+      dhcp_release(netif);
+      dhcp_discover(netif);
+    }
+  } else if (dhcp->state == DHCP_REBOOTING) {
+    if (dhcp->tries < REBOOT_TRIES) {
+      dhcp_reboot(netif);
+    } else {
+      dhcp_discover(netif);
+    }
+  }
+}
+
+/**
+ * The renewal period has timed out.
+ *
+ * @param netif the netif under DHCP control
+ */
+static void
+dhcp_t1_timeout(struct netif *netif)
+{
+  struct dhcp *dhcp = netif->dhcp;
+  LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_STATE, ("dhcp_t1_timeout()\n"));
+  if ((dhcp->state == DHCP_REQUESTING) || (dhcp->state == DHCP_BOUND) ||
+      (dhcp->state == DHCP_RENEWING)) {
+    /* just retry to renew - note that the rebind timer (t2) will
+     * eventually time-out if renew tries fail. */
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE,
+                ("dhcp_t1_timeout(): must renew\n"));
+    /* This slightly different to RFC2131: DHCPREQUEST will be sent from state
+       DHCP_RENEWING, not DHCP_BOUND */
+    dhcp_renew(netif);
+  }
+}
+
+/**
+ * The rebind period has timed out.
+ *
+ * @param netif the netif under DHCP control
+ */
+static void
+dhcp_t2_timeout(struct netif *netif)
+{
+  struct dhcp *dhcp = netif->dhcp;
+  LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_t2_timeout()\n"));
+  if ((dhcp->state == DHCP_REQUESTING) || (dhcp->state == DHCP_BOUND) ||
+      (dhcp->state == DHCP_RENEWING)) {
+    /* just retry to rebind */
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE,
+                ("dhcp_t2_timeout(): must rebind\n"));
+    /* This slightly different to RFC2131: DHCPREQUEST will be sent from state
+       DHCP_REBINDING, not DHCP_BOUND */
+    dhcp_rebind(netif);
+  }
+}
+
+/**
+ * Handle a DHCP ACK packet
+ *
+ * @param netif the netif under DHCP control
+ */
+static void
+dhcp_handle_ack(struct netif *netif)
+{
+  struct dhcp *dhcp = netif->dhcp;
+#if LWIP_DNS
+  u8_t n;
+#endif /* LWIP_DNS */
+
+  /* clear options we might not get from the ACK */
+  ip_addr_set_zero(&dhcp->offered_sn_mask);
+  ip_addr_set_zero(&dhcp->offered_gw_addr);
+#if LWIP_DHCP_BOOTP_FILE
+  ip_addr_set_zero(&dhcp->offered_si_addr);
+#endif /* LWIP_DHCP_BOOTP_FILE */
+
+  /* lease time given? */
+  if (dhcp_option_given(dhcp, DHCP_OPTION_IDX_LEASE_TIME)) {
+    /* remember offered lease time */
+    dhcp->offered_t0_lease = dhcp_get_option_value(dhcp, DHCP_OPTION_IDX_LEASE_TIME);
+  }
+  /* renewal period given? */
+  if (dhcp_option_given(dhcp, DHCP_OPTION_IDX_T1)) {
+    /* remember given renewal period */
+    dhcp->offered_t1_renew = dhcp_get_option_value(dhcp, DHCP_OPTION_IDX_T1);
+  } else {
+    /* calculate safe periods for renewal */
+    dhcp->offered_t1_renew = dhcp->offered_t0_lease / 2;
+  }
+
+  /* renewal period given? */
+  if (dhcp_option_given(dhcp, DHCP_OPTION_IDX_T2)) {
+    /* remember given rebind period */
+    dhcp->offered_t2_rebind = dhcp_get_option_value(dhcp, DHCP_OPTION_IDX_T2);
+  } else {
+    /* calculate safe periods for rebinding */
+    dhcp->offered_t2_rebind = dhcp->offered_t0_lease;
+  }
+
+  /* (y)our internet address */
+  ip_addr_copy(dhcp->offered_ip_addr, dhcp->msg_in->yiaddr);
+
+#if LWIP_DHCP_BOOTP_FILE
+  /* copy boot server address,
+     boot file name copied in dhcp_parse_reply if not overloaded */
+  ip_addr_copy(dhcp->offered_si_addr, dhcp->msg_in->siaddr);
+#endif /* LWIP_DHCP_BOOTP_FILE */
+
+  /* subnet mask given? */
+  if (dhcp_option_given(dhcp, DHCP_OPTION_IDX_SUBNET_MASK)) {
+    /* remember given subnet mask */
+    ip4_addr_set_u32(&dhcp->offered_sn_mask, htonl(dhcp_get_option_value(dhcp, DHCP_OPTION_IDX_SUBNET_MASK)));
+    dhcp->subnet_mask_given = 1;
+  } else {
+    dhcp->subnet_mask_given = 0;
+  }
+
+  /* gateway router */
+  if (dhcp_option_given(dhcp, DHCP_OPTION_IDX_ROUTER)) {
+    ip4_addr_set_u32(&dhcp->offered_gw_addr, htonl(dhcp_get_option_value(dhcp, DHCP_OPTION_IDX_ROUTER)));
+  }
+  
+#if LWIP_DNS
+  /* DNS servers */
+  n = 0;
+  while(dhcp_option_given(dhcp, DHCP_OPTION_IDX_DNS_SERVER + n) && (n < DNS_MAX_SERVERS)) {
+    ip_addr_t dns_addr;
+    ip4_addr_set_u32(&dns_addr, htonl(dhcp_get_option_value(dhcp, DHCP_OPTION_IDX_DNS_SERVER + n)));
+    dns_setserver(n, &dns_addr);
+    n++;
+  }
+#endif /* LWIP_DNS */
+}
+
+/** Set a statically allocated struct dhcp to work with.
+ * Using this prevents dhcp_start to allocate it using mem_malloc.
+ *
+ * @param netif the netif for which to set the struct dhcp
+ * @param dhcp (uninitialised) dhcp struct allocated by the application
+ */
+void
+dhcp_set_struct(struct netif *netif, struct dhcp *dhcp)
+{
+  LWIP_ASSERT("netif != NULL", netif != NULL);
+  LWIP_ASSERT("dhcp != NULL", dhcp != NULL);
+  LWIP_ASSERT("netif already has a struct dhcp set", netif->dhcp == NULL);
+
+  /* clear data structure */
+  memset(dhcp, 0, sizeof(struct dhcp));
+  /* dhcp_set_state(&dhcp, DHCP_OFF); */
+  netif->dhcp = dhcp;
+}
+
+/**
+ * Start DHCP negotiation for a network interface.
+ *
+ * If no DHCP client instance was attached to this interface,
+ * a new client is created first. If a DHCP client instance
+ * was already present, it restarts negotiation.
+ *
+ * @param netif The lwIP network interface
+ * @return lwIP error code
+ * - ERR_OK - No error
+ * - ERR_MEM - Out of memory
+ */
+err_t
+dhcp_start(struct netif *netif)
+{
+  struct dhcp *dhcp;
+  err_t result = ERR_OK;
+
+  LWIP_ERROR("netif != NULL", (netif != NULL), return ERR_ARG;);
+  dhcp = netif->dhcp;
+  LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_start(netif=%p) %c%c%"U16_F"\n", (void*)netif, netif->name[0], netif->name[1], (u16_t)netif->num));
+  /* Remove the flag that says this netif is handled by DHCP,
+     it is set when we succeeded starting. */
+  netif->flags &= ~NETIF_FLAG_DHCP;
+
+  /* check hwtype of the netif */
+  if ((netif->flags & NETIF_FLAG_ETHARP) == 0) {
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_start(): No ETHARP netif\n"));
+    return ERR_ARG;
+  }
+
+  /* check MTU of the netif */
+  if (netif->mtu < DHCP_MAX_MSG_LEN_MIN_REQUIRED) {
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_start(): Cannot use this netif with DHCP: MTU is too small\n"));
+    return ERR_MEM;
+  }
+
+  /* no DHCP client attached yet? */
+  if (dhcp == NULL) {
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_start(): starting new DHCP client\n"));
+    dhcp = (struct dhcp *)mem_malloc(sizeof(struct dhcp));
+    if (dhcp == NULL) {
+      LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_start(): could not allocate dhcp\n"));
+      return ERR_MEM;
+    }
+    /* store this dhcp client in the netif */
+    netif->dhcp = dhcp;
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_start(): allocated dhcp"));
+  /* already has DHCP client attached */
+  } else {
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_start(): restarting DHCP configuration\n"));
+    if (dhcp->pcb != NULL) {
+      udp_remove(dhcp->pcb);
+    }
+    LWIP_ASSERT("pbuf p_out wasn't freed", dhcp->p_out == NULL);
+    LWIP_ASSERT("reply wasn't freed", dhcp->msg_in == NULL );
+  }
+    
+  /* clear data structure */
+  memset(dhcp, 0, sizeof(struct dhcp));
+  /* dhcp_set_state(&dhcp, DHCP_OFF); */
+  /* allocate UDP PCB */
+  dhcp->pcb = udp_new();
+  if (dhcp->pcb == NULL) {
+    LWIP_DEBUGF(DHCP_DEBUG  | LWIP_DBG_TRACE, ("dhcp_start(): could not obtain pcb\n"));
+    return ERR_MEM;
+  }
+  dhcp->pcb->so_options |= SOF_BROADCAST;
+  /* set up local and remote port for the pcb */
+  udp_bind(dhcp->pcb, IP_ADDR_ANY, DHCP_CLIENT_PORT);
+  udp_connect(dhcp->pcb, IP_ADDR_ANY, DHCP_SERVER_PORT);
+  /* set up the recv callback and argument */
+  udp_recv(dhcp->pcb, dhcp_recv, netif);
+  LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_start(): starting DHCP configuration\n"));
+  /* (re)start the DHCP negotiation */
+  result = dhcp_discover(netif);
+  if (result != ERR_OK) {
+    /* free resources allocated above */
+    dhcp_stop(netif);
+    return ERR_MEM;
+  }
+  /* Set the flag that says this netif is handled by DHCP. */
+  netif->flags |= NETIF_FLAG_DHCP;
+  return result;
+}
+
+/**
+ * Inform a DHCP server of our manual configuration.
+ *
+ * This informs DHCP servers of our fixed IP address configuration
+ * by sending an INFORM message. It does not involve DHCP address
+ * configuration, it is just here to be nice to the network.
+ *
+ * @param netif The lwIP network interface
+ */
+void
+dhcp_inform(struct netif *netif)
+{
+  struct dhcp dhcp;
+  err_t result = ERR_OK;
+  struct udp_pcb *pcb;
+
+  LWIP_ERROR("netif != NULL", (netif != NULL), return;);
+
+  memset(&dhcp, 0, sizeof(struct dhcp));
+  dhcp_set_state(&dhcp, DHCP_INFORM);
+
+  if ((netif->dhcp != NULL) && (netif->dhcp->pcb != NULL)) {
+    /* re-use existing pcb */
+    pcb = netif->dhcp->pcb;
+  } else {
+    pcb = udp_new();
+    if (pcb == NULL) {
+      LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_SERIOUS, ("dhcp_inform(): could not obtain pcb"));
+      return;
+    }
+    dhcp.pcb = pcb;
+    dhcp.pcb->so_options |= SOF_BROADCAST;
+    udp_bind(dhcp.pcb, IP_ADDR_ANY, DHCP_CLIENT_PORT);
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_inform(): created new udp pcb\n"));
+  }
+  /* create and initialize the DHCP message header */
+  result = dhcp_create_msg(netif, &dhcp, DHCP_INFORM);
+  if (result == ERR_OK) {
+    dhcp_option(&dhcp, DHCP_OPTION_MAX_MSG_SIZE, DHCP_OPTION_MAX_MSG_SIZE_LEN);
+    dhcp_option_short(&dhcp, DHCP_MAX_MSG_LEN(netif));
+
+    dhcp_option_trailer(&dhcp);
+
+    pbuf_realloc(dhcp.p_out, sizeof(struct dhcp_msg) - DHCP_OPTIONS_LEN + dhcp.options_out_len);
+
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_inform: INFORMING\n"));
+    udp_sendto_if(pcb, dhcp.p_out, IP_ADDR_BROADCAST, DHCP_SERVER_PORT, netif);
+    dhcp_delete_msg(&dhcp);
+  } else {
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_SERIOUS, ("dhcp_inform: could not allocate DHCP request\n"));
+  }
+
+  if (dhcp.pcb != NULL) {
+    /* otherwise, the existing pcb was used */
+    udp_remove(dhcp.pcb);
+  }
+}
+
+/** Handle a possible change in the network configuration.
+ *
+ * This enters the REBOOTING state to verify that the currently bound
+ * address is still valid.
+ */
+void
+dhcp_network_changed(struct netif *netif)
+{
+  struct dhcp *dhcp = netif->dhcp;
+  if (!dhcp)
+    return;
+  switch (dhcp->state) {
+  case DHCP_REBINDING:
+  case DHCP_RENEWING:
+  case DHCP_BOUND:
+  case DHCP_REBOOTING:
+    netif_set_down(netif);
+    dhcp->tries = 0;
+    dhcp_reboot(netif);
+    break;
+  case DHCP_OFF:
+    /* stay off */
+    break;
+  default:
+    dhcp->tries = 0;
+#if LWIP_DHCP_AUTOIP_COOP
+    dhcp->autoip_coop_state = DHCP_AUTOIP_COOP_STATE_OFF;
+#endif /* LWIP_DHCP_AUTOIP_COOP */
+    dhcp_discover(netif);
+    break;
+  }
+}
+
+#if DHCP_DOES_ARP_CHECK
+/**
+ * Match an ARP reply with the offered IP address.
+ *
+ * @param netif the network interface on which the reply was received
+ * @param addr The IP address we received a reply from
+ */
+void dhcp_arp_reply(struct netif *netif, ip_addr_t *addr)
+{
+  LWIP_ERROR("netif != NULL", (netif != NULL), return;);
+  LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_arp_reply()\n"));
+  /* is a DHCP client doing an ARP check? */
+  if ((netif->dhcp != NULL) && (netif->dhcp->state == DHCP_CHECKING)) {
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_arp_reply(): CHECKING, arp reply for 0x%08"X32_F"\n",
+      ip4_addr_get_u32(addr)));
+    /* did a host respond with the address we
+       were offered by the DHCP server? */
+    if (ip_addr_cmp(addr, &netif->dhcp->offered_ip_addr)) {
+      /* we will not accept the offered address */
+      LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE | LWIP_DBG_LEVEL_WARNING,
+        ("dhcp_arp_reply(): arp reply matched with offered address, declining\n"));
+      dhcp_decline(netif);
+    }
+  }
+}
+
+/**
+ * Decline an offered lease.
+ *
+ * Tell the DHCP server we do not accept the offered address.
+ * One reason to decline the lease is when we find out the address
+ * is already in use by another host (through ARP).
+ *
+ * @param netif the netif under DHCP control
+ */
+static err_t
+dhcp_decline(struct netif *netif)
+{
+  struct dhcp *dhcp = netif->dhcp;
+  err_t result = ERR_OK;
+  u16_t msecs;
+  LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_decline()\n"));
+  dhcp_set_state(dhcp, DHCP_BACKING_OFF);
+  /* create and initialize the DHCP message header */
+  result = dhcp_create_msg(netif, dhcp, DHCP_DECLINE);
+  if (result == ERR_OK) {
+    dhcp_option(dhcp, DHCP_OPTION_REQUESTED_IP, 4);
+    dhcp_option_long(dhcp, ntohl(ip4_addr_get_u32(&dhcp->offered_ip_addr)));
+
+    dhcp_option_trailer(dhcp);
+    /* resize pbuf to reflect true size of options */
+    pbuf_realloc(dhcp->p_out, sizeof(struct dhcp_msg) - DHCP_OPTIONS_LEN + dhcp->options_out_len);
+
+    /* per section 4.4.4, broadcast DECLINE messages */
+    udp_sendto_if(dhcp->pcb, dhcp->p_out, IP_ADDR_BROADCAST, DHCP_SERVER_PORT, netif);
+    dhcp_delete_msg(dhcp);
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_decline: BACKING OFF\n"));
+  } else {
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_SERIOUS,
+      ("dhcp_decline: could not allocate DHCP request\n"));
+  }
+  dhcp->tries++;
+  msecs = 10*1000;
+  dhcp->request_timeout = (msecs + DHCP_FINE_TIMER_MSECS - 1) / DHCP_FINE_TIMER_MSECS;
+  LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_decline(): set request timeout %"U16_F" msecs\n", msecs));
+  return result;
+}
+#endif /* DHCP_DOES_ARP_CHECK */
+
+
+/**
+ * Start the DHCP process, discover a DHCP server.
+ *
+ * @param netif the netif under DHCP control
+ */
+static err_t
+dhcp_discover(struct netif *netif)
+{
+  struct dhcp *dhcp = netif->dhcp;
+  err_t result = ERR_OK;
+  u16_t msecs;
+  LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_discover()\n"));
+  ip_addr_set_any(&dhcp->offered_ip_addr);
+  dhcp_set_state(dhcp, DHCP_SELECTING);
+  /* create and initialize the DHCP message header */
+  result = dhcp_create_msg(netif, dhcp, DHCP_DISCOVER);
+  if (result == ERR_OK) {
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_discover: making request\n"));
+
+    dhcp_option(dhcp, DHCP_OPTION_MAX_MSG_SIZE, DHCP_OPTION_MAX_MSG_SIZE_LEN);
+    dhcp_option_short(dhcp, DHCP_MAX_MSG_LEN(netif));
+
+    dhcp_option(dhcp, DHCP_OPTION_PARAMETER_REQUEST_LIST, 4/*num options*/);
+    dhcp_option_byte(dhcp, DHCP_OPTION_SUBNET_MASK);
+    dhcp_option_byte(dhcp, DHCP_OPTION_ROUTER);
+    dhcp_option_byte(dhcp, DHCP_OPTION_BROADCAST);
+    dhcp_option_byte(dhcp, DHCP_OPTION_DNS_SERVER);
+
+    dhcp_option_trailer(dhcp);
+
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_discover: realloc()ing\n"));
+    pbuf_realloc(dhcp->p_out, sizeof(struct dhcp_msg) - DHCP_OPTIONS_LEN + dhcp->options_out_len);
+
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_discover: sendto(DISCOVER, IP_ADDR_BROADCAST, DHCP_SERVER_PORT)\n"));
+    udp_sendto_if(dhcp->pcb, dhcp->p_out, IP_ADDR_BROADCAST, DHCP_SERVER_PORT, netif);
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_discover: deleting()ing\n"));
+    dhcp_delete_msg(dhcp);
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_discover: SELECTING\n"));
+  } else {
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_SERIOUS, ("dhcp_discover: could not allocate DHCP request\n"));
+  }
+  dhcp->tries++;
+#if LWIP_DHCP_AUTOIP_COOP
+  if(dhcp->tries >= LWIP_DHCP_AUTOIP_COOP_TRIES && dhcp->autoip_coop_state == DHCP_AUTOIP_COOP_STATE_OFF) {
+    dhcp->autoip_coop_state = DHCP_AUTOIP_COOP_STATE_ON;
+    autoip_start(netif);
+  }
+#endif /* LWIP_DHCP_AUTOIP_COOP */
+  msecs = (dhcp->tries < 6 ? 1 << dhcp->tries : 60) * 1000;
+  dhcp->request_timeout = (msecs + DHCP_FINE_TIMER_MSECS - 1) / DHCP_FINE_TIMER_MSECS;
+  LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_discover(): set request timeout %"U16_F" msecs\n", msecs));
+  return result;
+}
+
+
+/**
+ * Bind the interface to the offered IP address.
+ *
+ * @param netif network interface to bind to the offered address
+ */
+static void
+dhcp_bind(struct netif *netif)
+{
+  u32_t timeout;
+  struct dhcp *dhcp;
+  ip_addr_t sn_mask, gw_addr;
+  LWIP_ERROR("dhcp_bind: netif != NULL", (netif != NULL), return;);
+  dhcp = netif->dhcp;
+  LWIP_ERROR("dhcp_bind: dhcp != NULL", (dhcp != NULL), return;);
+  LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_bind(netif=%p) %c%c%"U16_F"\n", (void*)netif, netif->name[0], netif->name[1], (u16_t)netif->num));
+
+  /* temporary DHCP lease? */
+  if (dhcp->offered_t1_renew != 0xffffffffUL) {
+    /* set renewal period timer */
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_bind(): t1 renewal timer %"U32_F" secs\n", dhcp->offered_t1_renew));
+    timeout = (dhcp->offered_t1_renew + DHCP_COARSE_TIMER_SECS / 2) / DHCP_COARSE_TIMER_SECS;
+    if(timeout > 0xffff) {
+      timeout = 0xffff;
+    }
+    dhcp->t1_timeout = (u16_t)timeout;
+    if (dhcp->t1_timeout == 0) {
+      dhcp->t1_timeout = 1;
+    }
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_bind(): set request timeout %"U32_F" msecs\n", dhcp->offered_t1_renew*1000));
+  }
+  /* set renewal period timer */
+  if (dhcp->offered_t2_rebind != 0xffffffffUL) {
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_bind(): t2 rebind timer %"U32_F" secs\n", dhcp->offered_t2_rebind));
+    timeout = (dhcp->offered_t2_rebind + DHCP_COARSE_TIMER_SECS / 2) / DHCP_COARSE_TIMER_SECS;
+    if(timeout > 0xffff) {
+      timeout = 0xffff;
+    }
+    dhcp->t2_timeout = (u16_t)timeout;
+    if (dhcp->t2_timeout == 0) {
+      dhcp->t2_timeout = 1;
+    }
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_bind(): set request timeout %"U32_F" msecs\n", dhcp->offered_t2_rebind*1000));
+  }
+
+  if (dhcp->subnet_mask_given) {
+    /* copy offered network mask */
+    ip_addr_copy(sn_mask, dhcp->offered_sn_mask);
+  } else {
+    /* subnet mask not given, choose a safe subnet mask given the network class */
+    u8_t first_octet = ip4_addr1(&dhcp->offered_ip_addr);
+    if (first_octet <= 127) {
+      ip4_addr_set_u32(&sn_mask, PP_HTONL(0xff000000));
+    } else if (first_octet >= 192) {
+      ip4_addr_set_u32(&sn_mask, PP_HTONL(0xffffff00));
+    } else {
+      ip4_addr_set_u32(&sn_mask, PP_HTONL(0xffff0000));
+    }
+  }
+
+  ip_addr_copy(gw_addr, dhcp->offered_gw_addr);
+  /* gateway address not given? */
+  if (ip_addr_isany(&gw_addr)) {
+    /* copy network address */
+    ip_addr_get_network(&gw_addr, &dhcp->offered_ip_addr, &sn_mask);
+    /* use first host address on network as gateway */
+    ip4_addr_set_u32(&gw_addr, ip4_addr_get_u32(&gw_addr) | PP_HTONL(0x00000001));
+  }
+
+#if LWIP_DHCP_AUTOIP_COOP
+  if(dhcp->autoip_coop_state == DHCP_AUTOIP_COOP_STATE_ON) {
+    autoip_stop(netif);
+    dhcp->autoip_coop_state = DHCP_AUTOIP_COOP_STATE_OFF;
+  }
+#endif /* LWIP_DHCP_AUTOIP_COOP */
+
+  LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_STATE, ("dhcp_bind(): IP: 0x%08"X32_F"\n",
+    ip4_addr_get_u32(&dhcp->offered_ip_addr)));
+  netif_set_ipaddr(netif, &dhcp->offered_ip_addr);
+  LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_STATE, ("dhcp_bind(): SN: 0x%08"X32_F"\n",
+    ip4_addr_get_u32(&sn_mask)));
+  netif_set_netmask(netif, &sn_mask);
+  LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_STATE, ("dhcp_bind(): GW: 0x%08"X32_F"\n",
+    ip4_addr_get_u32(&gw_addr)));
+  netif_set_gw(netif, &gw_addr);
+  /* bring the interface up */
+  netif_set_up(netif);
+  /* netif is now bound to DHCP leased address */
+  dhcp_set_state(dhcp, DHCP_BOUND);
+}
+
+/**
+ * Renew an existing DHCP lease at the involved DHCP server.
+ *
+ * @param netif network interface which must renew its lease
+ */
+err_t
+dhcp_renew(struct netif *netif)
+{
+  struct dhcp *dhcp = netif->dhcp;
+  err_t result;
+  u16_t msecs;
+  LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_renew()\n"));
+  dhcp_set_state(dhcp, DHCP_RENEWING);
+
+  /* create and initialize the DHCP message header */
+  result = dhcp_create_msg(netif, dhcp, DHCP_REQUEST);
+  if (result == ERR_OK) {
+    dhcp_option(dhcp, DHCP_OPTION_MAX_MSG_SIZE, DHCP_OPTION_MAX_MSG_SIZE_LEN);
+    dhcp_option_short(dhcp, DHCP_MAX_MSG_LEN(netif));
+
+#if LWIP_NETIF_HOSTNAME
+    if (netif->hostname != NULL) {
+      const char *p = (const char*)netif->hostname;
+      u8_t namelen = (u8_t)strlen(p);
+      if (namelen > 0) {
+        LWIP_ASSERT("DHCP: hostname is too long!", namelen < 255);
+        dhcp_option(dhcp, DHCP_OPTION_HOSTNAME, namelen);
+        while (*p) {
+          dhcp_option_byte(dhcp, *p++);
+        }
+      }
+    }
+#endif /* LWIP_NETIF_HOSTNAME */
+
+#if 0
+    dhcp_option(dhcp, DHCP_OPTION_REQUESTED_IP, 4);
+    dhcp_option_long(dhcp, ntohl(dhcp->offered_ip_addr.addr));
+#endif
+
+#if 0
+    dhcp_option(dhcp, DHCP_OPTION_SERVER_ID, 4);
+    dhcp_option_long(dhcp, ntohl(dhcp->server_ip_addr.addr));
+#endif
+    /* append DHCP message trailer */
+    dhcp_option_trailer(dhcp);
+
+    pbuf_realloc(dhcp->p_out, sizeof(struct dhcp_msg) - DHCP_OPTIONS_LEN + dhcp->options_out_len);
+
+    udp_sendto_if(dhcp->pcb, dhcp->p_out, &dhcp->server_ip_addr, DHCP_SERVER_PORT, netif);
+    dhcp_delete_msg(dhcp);
+
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_renew: RENEWING\n"));
+  } else {
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_SERIOUS, ("dhcp_renew: could not allocate DHCP request\n"));
+  }
+  dhcp->tries++;
+  /* back-off on retries, but to a maximum of 20 seconds */
+  msecs = dhcp->tries < 10 ? dhcp->tries * 2000 : 20 * 1000;
+  dhcp->request_timeout = (msecs + DHCP_FINE_TIMER_MSECS - 1) / DHCP_FINE_TIMER_MSECS;
+  LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_renew(): set request timeout %"U16_F" msecs\n", msecs));
+  return result;
+}
+
+/**
+ * Rebind with a DHCP server for an existing DHCP lease.
+ *
+ * @param netif network interface which must rebind with a DHCP server
+ */
+static err_t
+dhcp_rebind(struct netif *netif)
+{
+  struct dhcp *dhcp = netif->dhcp;
+  err_t result;
+  u16_t msecs;
+  LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_rebind()\n"));
+  dhcp_set_state(dhcp, DHCP_REBINDING);
+
+  /* create and initialize the DHCP message header */
+  result = dhcp_create_msg(netif, dhcp, DHCP_REQUEST);
+  if (result == ERR_OK) {
+    dhcp_option(dhcp, DHCP_OPTION_MAX_MSG_SIZE, DHCP_OPTION_MAX_MSG_SIZE_LEN);
+    dhcp_option_short(dhcp, DHCP_MAX_MSG_LEN(netif));
+
+#if LWIP_NETIF_HOSTNAME
+    if (netif->hostname != NULL) {
+      const char *p = (const char*)netif->hostname;
+      u8_t namelen = (u8_t)strlen(p);
+      if (namelen > 0) {
+        LWIP_ASSERT("DHCP: hostname is too long!", namelen < 255);
+        dhcp_option(dhcp, DHCP_OPTION_HOSTNAME, namelen);
+        while (*p) {
+          dhcp_option_byte(dhcp, *p++);
+        }
+      }
+    }
+#endif /* LWIP_NETIF_HOSTNAME */
+
+#if 0
+    dhcp_option(dhcp, DHCP_OPTION_REQUESTED_IP, 4);
+    dhcp_option_long(dhcp, ntohl(dhcp->offered_ip_addr.addr));
+
+    dhcp_option(dhcp, DHCP_OPTION_SERVER_ID, 4);
+    dhcp_option_long(dhcp, ntohl(dhcp->server_ip_addr.addr));
+#endif
+
+    dhcp_option_trailer(dhcp);
+
+    pbuf_realloc(dhcp->p_out, sizeof(struct dhcp_msg) - DHCP_OPTIONS_LEN + dhcp->options_out_len);
+
+    /* broadcast to server */
+    udp_sendto_if(dhcp->pcb, dhcp->p_out, IP_ADDR_BROADCAST, DHCP_SERVER_PORT, netif);
+    dhcp_delete_msg(dhcp);
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_rebind: REBINDING\n"));
+  } else {
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_SERIOUS, ("dhcp_rebind: could not allocate DHCP request\n"));
+  }
+  dhcp->tries++;
+  msecs = dhcp->tries < 10 ? dhcp->tries * 1000 : 10 * 1000;
+  dhcp->request_timeout = (msecs + DHCP_FINE_TIMER_MSECS - 1) / DHCP_FINE_TIMER_MSECS;
+  LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_rebind(): set request timeout %"U16_F" msecs\n", msecs));
+  return result;
+}
+
+/**
+ * Enter REBOOTING state to verify an existing lease
+ *
+ * @param netif network interface which must reboot
+ */
+static err_t
+dhcp_reboot(struct netif *netif)
+{
+  struct dhcp *dhcp = netif->dhcp;
+  err_t result;
+  u16_t msecs;
+  LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_reboot()\n"));
+  dhcp_set_state(dhcp, DHCP_REBOOTING);
+
+  /* create and initialize the DHCP message header */
+  result = dhcp_create_msg(netif, dhcp, DHCP_REQUEST);
+  if (result == ERR_OK) {
+    dhcp_option(dhcp, DHCP_OPTION_MAX_MSG_SIZE, DHCP_OPTION_MAX_MSG_SIZE_LEN);
+    dhcp_option_short(dhcp, 576);
+
+    dhcp_option(dhcp, DHCP_OPTION_REQUESTED_IP, 4);
+    dhcp_option_long(dhcp, ntohl(ip4_addr_get_u32(&dhcp->offered_ip_addr)));
+
+    dhcp_option_trailer(dhcp);
+
+    pbuf_realloc(dhcp->p_out, sizeof(struct dhcp_msg) - DHCP_OPTIONS_LEN + dhcp->options_out_len);
+
+    /* broadcast to server */
+    udp_sendto_if(dhcp->pcb, dhcp->p_out, IP_ADDR_BROADCAST, DHCP_SERVER_PORT, netif);
+    dhcp_delete_msg(dhcp);
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_reboot: REBOOTING\n"));
+  } else {
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_SERIOUS, ("dhcp_reboot: could not allocate DHCP request\n"));
+  }
+  dhcp->tries++;
+  msecs = dhcp->tries < 10 ? dhcp->tries * 1000 : 10 * 1000;
+  dhcp->request_timeout = (msecs + DHCP_FINE_TIMER_MSECS - 1) / DHCP_FINE_TIMER_MSECS;
+  LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_reboot(): set request timeout %"U16_F" msecs\n", msecs));
+  return result;
+}
+
+
+/**
+ * Release a DHCP lease.
+ *
+ * @param netif network interface which must release its lease
+ */
+err_t
+dhcp_release(struct netif *netif)
+{
+  struct dhcp *dhcp = netif->dhcp;
+  err_t result;
+  u16_t msecs;
+  LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_release()\n"));
+
+  /* idle DHCP client */
+  dhcp_set_state(dhcp, DHCP_OFF);
+  /* clean old DHCP offer */
+  ip_addr_set_zero(&dhcp->server_ip_addr);
+  ip_addr_set_zero(&dhcp->offered_ip_addr);
+  ip_addr_set_zero(&dhcp->offered_sn_mask);
+  ip_addr_set_zero(&dhcp->offered_gw_addr);
+#if LWIP_DHCP_BOOTP_FILE
+  ip_addr_set_zero(&dhcp->offered_si_addr);
+#endif /* LWIP_DHCP_BOOTP_FILE */
+  dhcp->offered_t0_lease = dhcp->offered_t1_renew = dhcp->offered_t2_rebind = 0;
+  
+  /* create and initialize the DHCP message header */
+  result = dhcp_create_msg(netif, dhcp, DHCP_RELEASE);
+  if (result == ERR_OK) {
+    dhcp_option_trailer(dhcp);
+
+    pbuf_realloc(dhcp->p_out, sizeof(struct dhcp_msg) - DHCP_OPTIONS_LEN + dhcp->options_out_len);
+
+    udp_sendto_if(dhcp->pcb, dhcp->p_out, &dhcp->server_ip_addr, DHCP_SERVER_PORT, netif);
+    dhcp_delete_msg(dhcp);
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_release: RELEASED, DHCP_OFF\n"));
+  } else {
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_SERIOUS, ("dhcp_release: could not allocate DHCP request\n"));
+  }
+  dhcp->tries++;
+  msecs = dhcp->tries < 10 ? dhcp->tries * 1000 : 10 * 1000;
+  dhcp->request_timeout = (msecs + DHCP_FINE_TIMER_MSECS - 1) / DHCP_FINE_TIMER_MSECS;
+  LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_release(): set request timeout %"U16_F" msecs\n", msecs));
+  /* bring the interface down */
+  netif_set_down(netif);
+  /* remove IP address from interface */
+  netif_set_ipaddr(netif, IP_ADDR_ANY);
+  netif_set_gw(netif, IP_ADDR_ANY);
+  netif_set_netmask(netif, IP_ADDR_ANY);
+  
+  return result;
+}
+
+/**
+ * Remove the DHCP client from the interface.
+ *
+ * @param netif The network interface to stop DHCP on
+ */
+void
+dhcp_stop(struct netif *netif)
+{
+  struct dhcp *dhcp;
+  LWIP_ERROR("dhcp_stop: netif != NULL", (netif != NULL), return;);
+  dhcp = netif->dhcp;
+  /* Remove the flag that says this netif is handled by DHCP. */
+  netif->flags &= ~NETIF_FLAG_DHCP;
+
+  LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_stop()\n"));
+  /* netif is DHCP configured? */
+  if (dhcp != NULL) {
+#if LWIP_DHCP_AUTOIP_COOP
+    if(dhcp->autoip_coop_state == DHCP_AUTOIP_COOP_STATE_ON) {
+      autoip_stop(netif);
+      dhcp->autoip_coop_state = DHCP_AUTOIP_COOP_STATE_OFF;
+    }
+#endif /* LWIP_DHCP_AUTOIP_COOP */
+
+    if (dhcp->pcb != NULL) {
+      udp_remove(dhcp->pcb);
+      dhcp->pcb = NULL;
+    }
+    LWIP_ASSERT("reply wasn't freed", dhcp->msg_in == NULL);
+    dhcp_set_state(dhcp, DHCP_OFF);
+  }
+}
+
+/*
+ * Set the DHCP state of a DHCP client.
+ *
+ * If the state changed, reset the number of tries.
+ */
+static void
+dhcp_set_state(struct dhcp *dhcp, u8_t new_state)
+{
+  if (new_state != dhcp->state) {
+    dhcp->state = new_state;
+    dhcp->tries = 0;
+    dhcp->request_timeout = 0;
+  }
+}
+
+/*
+ * Concatenate an option type and length field to the outgoing
+ * DHCP message.
+ *
+ */
+static void
+dhcp_option(struct dhcp *dhcp, u8_t option_type, u8_t option_len)
+{
+  LWIP_ASSERT("dhcp_option: dhcp->options_out_len + 2 + option_len <= DHCP_OPTIONS_LEN", dhcp->options_out_len + 2U + option_len <= DHCP_OPTIONS_LEN);
+  dhcp->msg_out->options[dhcp->options_out_len++] = option_type;
+  dhcp->msg_out->options[dhcp->options_out_len++] = option_len;
+}
+/*
+ * Concatenate a single byte to the outgoing DHCP message.
+ *
+ */
+static void
+dhcp_option_byte(struct dhcp *dhcp, u8_t value)
+{
+  LWIP_ASSERT("dhcp_option_byte: dhcp->options_out_len < DHCP_OPTIONS_LEN", dhcp->options_out_len < DHCP_OPTIONS_LEN);
+  dhcp->msg_out->options[dhcp->options_out_len++] = value;
+}
+
+static void
+dhcp_option_short(struct dhcp *dhcp, u16_t value)
+{
+  LWIP_ASSERT("dhcp_option_short: dhcp->options_out_len + 2 <= DHCP_OPTIONS_LEN", dhcp->options_out_len + 2U <= DHCP_OPTIONS_LEN);
+  dhcp->msg_out->options[dhcp->options_out_len++] = (u8_t)((value & 0xff00U) >> 8);
+  dhcp->msg_out->options[dhcp->options_out_len++] = (u8_t) (value & 0x00ffU);
+}
+
+static void
+dhcp_option_long(struct dhcp *dhcp, u32_t value)
+{
+  LWIP_ASSERT("dhcp_option_long: dhcp->options_out_len + 4 <= DHCP_OPTIONS_LEN", dhcp->options_out_len + 4U <= DHCP_OPTIONS_LEN);
+  dhcp->msg_out->options[dhcp->options_out_len++] = (u8_t)((value & 0xff000000UL) >> 24);
+  dhcp->msg_out->options[dhcp->options_out_len++] = (u8_t)((value & 0x00ff0000UL) >> 16);
+  dhcp->msg_out->options[dhcp->options_out_len++] = (u8_t)((value & 0x0000ff00UL) >> 8);
+  dhcp->msg_out->options[dhcp->options_out_len++] = (u8_t)((value & 0x000000ffUL));
+}
+
+/**
+ * Extract the DHCP message and the DHCP options.
+ *
+ * Extract the DHCP message and the DHCP options, each into a contiguous
+ * piece of memory. As a DHCP message is variable sized by its options,
+ * and also allows overriding some fields for options, the easy approach
+ * is to first unfold the options into a conitguous piece of memory, and
+ * use that further on.
+ *
+ */
+static err_t
+dhcp_parse_reply(struct dhcp *dhcp, struct pbuf *p)
+{
+  u8_t *options;
+  u16_t offset;
+  u16_t offset_max;
+  u16_t options_idx;
+  u16_t options_idx_max;
+  struct pbuf *q;
+  int parse_file_as_options = 0;
+  int parse_sname_as_options = 0;
+
+  /* clear received options */
+  dhcp_clear_all_options(dhcp);
+  /* check that beginning of dhcp_msg (up to and including chaddr) is in first pbuf */
+  if (p->len < DHCP_SNAME_OFS) {
+    return ERR_BUF;
+  }
+  dhcp->msg_in = (struct dhcp_msg *)p->payload;
+#if LWIP_DHCP_BOOTP_FILE
+  /* clear boot file name */
+  dhcp->boot_file_name[0] = 0;
+#endif /* LWIP_DHCP_BOOTP_FILE */
+
+  /* parse options */
+
+  /* start with options field */
+  options_idx = DHCP_OPTIONS_OFS;
+  /* parse options to the end of the received packet */
+  options_idx_max = p->tot_len;
+again:
+  q = p;
+  while((q != NULL) && (options_idx >= q->len)) {
+    options_idx -= q->len;
+    options_idx_max -= q->len;
+    q = q->next;
+  }
+  if (q == NULL) {
+    return ERR_BUF;
+  }
+  offset = options_idx;
+  offset_max = options_idx_max;
+  options = (u8_t*)q->payload;
+  /* at least 1 byte to read and no end marker, then at least 3 bytes to read? */
+  while((q != NULL) && (options[offset] != DHCP_OPTION_END) && (offset < offset_max)) {
+    u8_t op = options[offset];
+    u8_t len;
+    u8_t decode_len = 0;
+    int decode_idx = -1;
+    u16_t val_offset = offset + 2;
+    /* len byte might be in the next pbuf */
+    if (offset + 1 < q->len) {
+      len = options[offset + 1];
+    } else {
+      len = (q->next != NULL ? ((u8_t*)q->next->payload)[0] : 0);
+    }
+    /* LWIP_DEBUGF(DHCP_DEBUG, ("msg_offset=%"U16_F", q->len=%"U16_F, msg_offset, q->len)); */
+    decode_len = len;
+    switch(op) {
+      /* case(DHCP_OPTION_END): handled above */
+      case(DHCP_OPTION_PAD):
+        /* special option: no len encoded */
+        decode_len = len = 0;
+        /* will be increased below */
+        offset--;
+        break;
+      case(DHCP_OPTION_SUBNET_MASK):
+        LWIP_ASSERT("len == 4", len == 4);
+        decode_idx = DHCP_OPTION_IDX_SUBNET_MASK;
+        break;
+      case(DHCP_OPTION_ROUTER):
+        decode_len = 4; /* only copy the first given router */
+        LWIP_ASSERT("len >= decode_len", len >= decode_len);
+        decode_idx = DHCP_OPTION_IDX_ROUTER;
+        break;
+      case(DHCP_OPTION_DNS_SERVER):
+        /* special case: there might be more than one server */
+        LWIP_ASSERT("len % 4 == 0", len % 4 == 0);
+        /* limit number of DNS servers */
+        decode_len = LWIP_MIN(len, 4 * DNS_MAX_SERVERS);
+        LWIP_ASSERT("len >= decode_len", len >= decode_len);
+        decode_idx = DHCP_OPTION_IDX_DNS_SERVER;
+        break;
+      case(DHCP_OPTION_LEASE_TIME):
+        LWIP_ASSERT("len == 4", len == 4);
+        decode_idx = DHCP_OPTION_IDX_LEASE_TIME;
+        break;
+      case(DHCP_OPTION_OVERLOAD):
+        LWIP_ASSERT("len == 1", len == 1);
+        decode_idx = DHCP_OPTION_IDX_OVERLOAD;
+        break;
+      case(DHCP_OPTION_MESSAGE_TYPE):
+        LWIP_ASSERT("len == 1", len == 1);
+        decode_idx = DHCP_OPTION_IDX_MSG_TYPE;
+        break;
+      case(DHCP_OPTION_SERVER_ID):
+        LWIP_ASSERT("len == 4", len == 4);
+        decode_idx = DHCP_OPTION_IDX_SERVER_ID;
+        break;
+      case(DHCP_OPTION_T1):
+        LWIP_ASSERT("len == 4", len == 4);
+        decode_idx = DHCP_OPTION_IDX_T1;
+        break;
+      case(DHCP_OPTION_T2):
+        LWIP_ASSERT("len == 4", len == 4);
+        decode_idx = DHCP_OPTION_IDX_T2;
+        break;
+      default:
+        decode_len = 0;
+        LWIP_DEBUGF(DHCP_DEBUG, ("skipping option %"U16_F" in options\n", op));
+        break;
+    }
+    offset += len + 2;
+    if (decode_len > 0) {
+      u32_t value = 0;
+      u16_t copy_len;
+decode_next:
+      LWIP_ASSERT("check decode_idx", decode_idx >= 0 && decode_idx < DHCP_OPTION_IDX_MAX);
+      LWIP_ASSERT("option already decoded", !dhcp_option_given(dhcp, decode_idx));
+      copy_len = LWIP_MIN(decode_len, 4);
+      pbuf_copy_partial(q, &value, copy_len, val_offset);
+      if (decode_len > 4) {
+        /* decode more than one u32_t */
+        LWIP_ASSERT("decode_len % 4 == 0", decode_len % 4 == 0);
+        dhcp_got_option(dhcp, decode_idx);
+        dhcp_set_option_value(dhcp, decode_idx, htonl(value));
+        decode_len -= 4;
+        val_offset += 4;
+        decode_idx++;
+        goto decode_next;
+      } else if (decode_len == 4) {
+        value = ntohl(value);
+      } else {
+        LWIP_ASSERT("invalid decode_len", decode_len == 1);
+        value = ((u8_t*)&value)[0];
+      }
+      dhcp_got_option(dhcp, decode_idx);
+      dhcp_set_option_value(dhcp, decode_idx, value);
+    }
+    if (offset >= q->len) {
+      offset -= q->len;
+      offset_max -= q->len;
+      q = q->next;
+      options = (u8_t*)q->payload;
+    }
+  }
+  /* is this an overloaded message? */
+  if (dhcp_option_given(dhcp, DHCP_OPTION_IDX_OVERLOAD)) {
+    u32_t overload = dhcp_get_option_value(dhcp, DHCP_OPTION_IDX_OVERLOAD);
+    dhcp_clear_option(dhcp, DHCP_OPTION_IDX_OVERLOAD);
+    if (overload == DHCP_OVERLOAD_FILE) {
+      parse_file_as_options = 1;
+      LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("overloaded file field\n"));
+    } else if (overload == DHCP_OVERLOAD_SNAME) {
+      parse_sname_as_options = 1;
+      LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("overloaded sname field\n"));
+    } else if (overload == DHCP_OVERLOAD_SNAME_FILE) {
+      parse_sname_as_options = 1;
+      parse_file_as_options = 1;
+      LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("overloaded sname and file field\n"));
+    } else {
+      LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("invalid overload option: %d\n", (int)overload));
+    }
+#if LWIP_DHCP_BOOTP_FILE
+    if (!parse_file_as_options) {
+      /* only do this for ACK messages */
+      if (dhcp_option_given(dhcp, DHCP_OPTION_IDX_MSG_TYPE) &&
+        (dhcp_get_option_value(dhcp, DHCP_OPTION_IDX_MSG_TYPE) == DHCP_ACK))
+      /* copy bootp file name, don't care for sname (server hostname) */
+      pbuf_copy_partial(p, dhcp->boot_file_name, DHCP_FILE_LEN-1, DHCP_FILE_OFS);
+      /* make sure the string is really NULL-terminated */
+      dhcp->boot_file_name[DHCP_FILE_LEN-1] = 0;
+    }
+#endif /* LWIP_DHCP_BOOTP_FILE */
+  }
+  if (parse_file_as_options) {
+    /* if both are overloaded, parse file first and then sname (RFC 2131 ch. 4.1) */
+    parse_file_as_options = 0;
+    options_idx = DHCP_FILE_OFS;
+    options_idx_max = DHCP_FILE_OFS + DHCP_FILE_LEN;
+    goto again;
+  } else if (parse_sname_as_options) {
+    parse_sname_as_options = 0;
+    options_idx = DHCP_SNAME_OFS;
+    options_idx_max = DHCP_SNAME_OFS + DHCP_SNAME_LEN;
+    goto again;
+  }
+  return ERR_OK;
+}
+
+/**
+ * If an incoming DHCP message is in response to us, then trigger the state machine
+ */
+static void
+dhcp_recv(void *arg, struct udp_pcb *pcb, struct pbuf *p, ip_addr_t *addr, u16_t port)
+{
+  struct netif *netif = (struct netif *)arg;
+  struct dhcp *dhcp = netif->dhcp;
+  struct dhcp_msg *reply_msg = (struct dhcp_msg *)p->payload;
+  u8_t msg_type;
+  u8_t i;
+  LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_recv(pbuf = %p) from DHCP server %"U16_F".%"U16_F".%"U16_F".%"U16_F" port %"U16_F"\n", (void*)p,
+    ip4_addr1_16(addr), ip4_addr2_16(addr), ip4_addr3_16(addr), ip4_addr4_16(addr), port));
+  LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("pbuf->len = %"U16_F"\n", p->len));
+  LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("pbuf->tot_len = %"U16_F"\n", p->tot_len));
+  /* prevent warnings about unused arguments */
+  LWIP_UNUSED_ARG(pcb);
+  LWIP_UNUSED_ARG(addr);
+  LWIP_UNUSED_ARG(port);
+
+  LWIP_ASSERT("reply wasn't freed", dhcp->msg_in == NULL);
+
+  if (p->len < DHCP_MIN_REPLY_LEN) {
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_WARNING, ("DHCP reply message or pbuf too short\n"));
+    goto free_pbuf_and_return;
+  }
+
+  if (reply_msg->op != DHCP_BOOTREPLY) {
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_WARNING, ("not a DHCP reply message, but type %"U16_F"\n", (u16_t)reply_msg->op));
+    goto free_pbuf_and_return;
+  }
+  /* iterate through hardware address and match against DHCP message */
+  for (i = 0; i < netif->hwaddr_len; i++) {
+    if (netif->hwaddr[i] != reply_msg->chaddr[i]) {
+      LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_WARNING,
+        ("netif->hwaddr[%"U16_F"]==%02"X16_F" != reply_msg->chaddr[%"U16_F"]==%02"X16_F"\n",
+        (u16_t)i, (u16_t)netif->hwaddr[i], (u16_t)i, (u16_t)reply_msg->chaddr[i]));
+      goto free_pbuf_and_return;
+    }
+  }
+  /* match transaction ID against what we expected */
+  if (ntohl(reply_msg->xid) != dhcp->xid) {
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_WARNING,
+      ("transaction id mismatch reply_msg->xid(%"X32_F")!=dhcp->xid(%"X32_F")\n",ntohl(reply_msg->xid),dhcp->xid));
+    goto free_pbuf_and_return;
+  }
+  /* option fields could be unfold? */
+  if (dhcp_parse_reply(dhcp, p) != ERR_OK) {
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_SERIOUS,
+      ("problem unfolding DHCP message - too short on memory?\n"));
+    goto free_pbuf_and_return;
+  }
+
+  LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("searching DHCP_OPTION_MESSAGE_TYPE\n"));
+  /* obtain pointer to DHCP message type */
+  if (!dhcp_option_given(dhcp, DHCP_OPTION_IDX_MSG_TYPE)) {
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_WARNING, ("DHCP_OPTION_MESSAGE_TYPE option not found\n"));
+    goto free_pbuf_and_return;
+  }
+
+  /* read DHCP message type */
+  msg_type = (u8_t)dhcp_get_option_value(dhcp, DHCP_OPTION_IDX_MSG_TYPE);
+  /* message type is DHCP ACK? */
+  if (msg_type == DHCP_ACK) {
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("DHCP_ACK received\n"));
+    /* in requesting state? */
+    if (dhcp->state == DHCP_REQUESTING) {
+      dhcp_handle_ack(netif);
+#if DHCP_DOES_ARP_CHECK
+      /* check if the acknowledged lease address is already in use */
+      dhcp_check(netif);
+#else
+      /* bind interface to the acknowledged lease address */
+      dhcp_bind(netif);
+#endif
+    }
+    /* already bound to the given lease address? */
+    else if ((dhcp->state == DHCP_REBOOTING) || (dhcp->state == DHCP_REBINDING) || (dhcp->state == DHCP_RENEWING)) {
+      dhcp_bind(netif);
+    }
+  }
+  /* received a DHCP_NAK in appropriate state? */
+  else if ((msg_type == DHCP_NAK) &&
+    ((dhcp->state == DHCP_REBOOTING) || (dhcp->state == DHCP_REQUESTING) ||
+     (dhcp->state == DHCP_REBINDING) || (dhcp->state == DHCP_RENEWING  ))) {
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("DHCP_NAK received\n"));
+    dhcp_handle_nak(netif);
+  }
+  /* received a DHCP_OFFER in DHCP_SELECTING state? */
+  else if ((msg_type == DHCP_OFFER) && (dhcp->state == DHCP_SELECTING)) {
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("DHCP_OFFER received in DHCP_SELECTING state\n"));
+    dhcp->request_timeout = 0;
+    /* remember offered lease */
+    dhcp_handle_offer(netif);
+  }
+free_pbuf_and_return:
+  dhcp->msg_in = NULL;
+  pbuf_free(p);
+}
+
+/**
+ * Create a DHCP request, fill in common headers
+ *
+ * @param netif the netif under DHCP control
+ * @param dhcp dhcp control struct
+ * @param message_type message type of the request
+ */
+static err_t
+dhcp_create_msg(struct netif *netif, struct dhcp *dhcp, u8_t message_type)
+{
+  u16_t i;
+#ifndef DHCP_GLOBAL_XID
+  /** default global transaction identifier starting value (easy to match
+   *  with a packet analyser). We simply increment for each new request.
+   *  Predefine DHCP_GLOBAL_XID to a better value or a function call to generate one
+   *  at runtime, any supporting function prototypes can be defined in DHCP_GLOBAL_XID_HEADER */
+  static u32_t xid = 0xABCD0000;
+#else
+  static u32_t xid;
+  static u8_t xid_initialised = 0;
+  if (!xid_initialised) {
+    xid = DHCP_GLOBAL_XID;
+    xid_initialised = !xid_initialised;
+  }
+#endif
+  LWIP_ERROR("dhcp_create_msg: netif != NULL", (netif != NULL), return ERR_ARG;);
+  LWIP_ERROR("dhcp_create_msg: dhcp != NULL", (dhcp != NULL), return ERR_VAL;);
+  LWIP_ASSERT("dhcp_create_msg: dhcp->p_out == NULL", dhcp->p_out == NULL);
+  LWIP_ASSERT("dhcp_create_msg: dhcp->msg_out == NULL", dhcp->msg_out == NULL);
+  dhcp->p_out = pbuf_alloc(PBUF_TRANSPORT, sizeof(struct dhcp_msg), PBUF_RAM);
+  if (dhcp->p_out == NULL) {
+    LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_SERIOUS,
+      ("dhcp_create_msg(): could not allocate pbuf\n"));
+    return ERR_MEM;
+  }
+  LWIP_ASSERT("dhcp_create_msg: check that first pbuf can hold struct dhcp_msg",
+           (dhcp->p_out->len >= sizeof(struct dhcp_msg)));
+
+  /* reuse transaction identifier in retransmissions */
+  if (dhcp->tries == 0) {
+      xid++;
+  }
+  dhcp->xid = xid;
+  LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE,
+              ("transaction id xid(%"X32_F")\n", xid));
+
+  dhcp->msg_out = (struct dhcp_msg *)dhcp->p_out->payload;
+
+  dhcp->msg_out->op = DHCP_BOOTREQUEST;
+  /* TODO: make link layer independent */
+  dhcp->msg_out->htype = DHCP_HTYPE_ETH;
+  dhcp->msg_out->hlen = netif->hwaddr_len;
+  dhcp->msg_out->hops = 0;
+  dhcp->msg_out->xid = htonl(dhcp->xid);
+  dhcp->msg_out->secs = 0;
+  /* we don't need the broadcast flag since we can receive unicast traffic
+     before being fully configured! */
+  dhcp->msg_out->flags = 0;
+  ip_addr_set_zero(&dhcp->msg_out->ciaddr);
+  /* set ciaddr to netif->ip_addr based on message_type and state */
+  if ((message_type == DHCP_INFORM) || (message_type == DHCP_DECLINE) ||
+      ((message_type == DHCP_REQUEST) && /* DHCP_BOUND not used for sending! */
+       ((dhcp->state==DHCP_RENEWING) || dhcp->state==DHCP_REBINDING))) {
+    ip_addr_copy(dhcp->msg_out->ciaddr, netif->ip_addr);
+  }
+  ip_addr_set_zero(&dhcp->msg_out->yiaddr);
+  ip_addr_set_zero(&dhcp->msg_out->siaddr);
+  ip_addr_set_zero(&dhcp->msg_out->giaddr);
+  for (i = 0; i < DHCP_CHADDR_LEN; i++) {
+    /* copy netif hardware address, pad with zeroes */
+    dhcp->msg_out->chaddr[i] = (i < netif->hwaddr_len) ? netif->hwaddr[i] : 0/* pad byte*/;
+  }
+  for (i = 0; i < DHCP_SNAME_LEN; i++) {
+    dhcp->msg_out->sname[i] = 0;
+  }
+  for (i = 0; i < DHCP_FILE_LEN; i++) {
+    dhcp->msg_out->file[i] = 0;
+  }
+  dhcp->msg_out->cookie = PP_HTONL(DHCP_MAGIC_COOKIE);
+  dhcp->options_out_len = 0;
+  /* fill options field with an incrementing array (for debugging purposes) */
+  for (i = 0; i < DHCP_OPTIONS_LEN; i++) {
+    dhcp->msg_out->options[i] = (u8_t)i; /* for debugging only, no matter if truncated */
+  }
+  /* Add option MESSAGE_TYPE */
+  dhcp_option(dhcp, DHCP_OPTION_MESSAGE_TYPE, DHCP_OPTION_MESSAGE_TYPE_LEN);
+  dhcp_option_byte(dhcp, message_type);
+  return ERR_OK;
+}
+
+/**
+ * Free previously allocated memory used to send a DHCP request.
+ *
+ * @param dhcp the dhcp struct to free the request from
+ */
+static void
+dhcp_delete_msg(struct dhcp *dhcp)
+{
+  LWIP_ERROR("dhcp_delete_msg: dhcp != NULL", (dhcp != NULL), return;);
+  LWIP_ASSERT("dhcp_delete_msg: dhcp->p_out != NULL", dhcp->p_out != NULL);
+  LWIP_ASSERT("dhcp_delete_msg: dhcp->msg_out != NULL", dhcp->msg_out != NULL);
+  if (dhcp->p_out != NULL) {
+    pbuf_free(dhcp->p_out);
+  }
+  dhcp->p_out = NULL;
+  dhcp->msg_out = NULL;
+}
+
+/**
+ * Add a DHCP message trailer
+ *
+ * Adds the END option to the DHCP message, and if
+ * necessary, up to three padding bytes.
+ *
+ * @param dhcp DHCP state structure
+ */
+static void
+dhcp_option_trailer(struct dhcp *dhcp)
+{
+  LWIP_ERROR("dhcp_option_trailer: dhcp != NULL", (dhcp != NULL), return;);
+  LWIP_ASSERT("dhcp_option_trailer: dhcp->msg_out != NULL\n", dhcp->msg_out != NULL);
+  LWIP_ASSERT("dhcp_option_trailer: dhcp->options_out_len < DHCP_OPTIONS_LEN\n", dhcp->options_out_len < DHCP_OPTIONS_LEN);
+  dhcp->msg_out->options[dhcp->options_out_len++] = DHCP_OPTION_END;
+  /* packet is too small, or not 4 byte aligned? */
+  while ((dhcp->options_out_len < DHCP_MIN_OPTIONS_LEN) || (dhcp->options_out_len & 3)) {
+    /* LWIP_DEBUGF(DHCP_DEBUG,("dhcp_option_trailer:dhcp->options_out_len=%"U16_F", DHCP_OPTIONS_LEN=%"U16_F, dhcp->options_out_len, DHCP_OPTIONS_LEN)); */
+    LWIP_ASSERT("dhcp_option_trailer: dhcp->options_out_len < DHCP_OPTIONS_LEN\n", dhcp->options_out_len < DHCP_OPTIONS_LEN);
+    /* add a fill/padding byte */
+    dhcp->msg_out->options[dhcp->options_out_len++] = 0;
+  }
+}
+
+#endif /* LWIP_DHCP */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/core/dns.c	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,969 @@
+/**
+ * @file
+ * DNS - host name to IP address resolver.
+ *
+ */
+
+/**
+
+ * This file implements a DNS host name to IP address resolver.
+
+ * Port to lwIP from uIP
+ * by Jim Pettinato April 2007
+
+ * uIP version Copyright (c) 2002-2003, Adam Dunkels.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote
+ *    products derived from this software without specific prior
+ *    written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
+ * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
+ * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ *
+ * DNS.C
+ *
+ * The lwIP DNS resolver functions are used to lookup a host name and
+ * map it to a numerical IP address. It maintains a list of resolved
+ * hostnames that can be queried with the dns_lookup() function.
+ * New hostnames can be resolved using the dns_query() function.
+ *
+ * The lwIP version of the resolver also adds a non-blocking version of
+ * gethostbyname() that will work with a raw API application. This function
+ * checks for an IP address string first and converts it if it is valid.
+ * gethostbyname() then does a dns_lookup() to see if the name is 
+ * already in the table. If so, the IP is returned. If not, a query is 
+ * issued and the function returns with a ERR_INPROGRESS status. The app
+ * using the dns client must then go into a waiting state.
+ *
+ * Once a hostname has been resolved (or found to be non-existent),
+ * the resolver code calls a specified callback function (which 
+ * must be implemented by the module that uses the resolver).
+ */
+
+/*-----------------------------------------------------------------------------
+ * RFC 1035 - Domain names - implementation and specification
+ * RFC 2181 - Clarifications to the DNS Specification
+ *----------------------------------------------------------------------------*/
+
+/** @todo: define good default values (rfc compliance) */
+/** @todo: improve answer parsing, more checkings... */
+/** @todo: check RFC1035 - 7.3. Processing responses */
+
+/*-----------------------------------------------------------------------------
+ * Includes
+ *----------------------------------------------------------------------------*/
+
+#include "lwip/opt.h"
+
+#if LWIP_DNS /* don't build if not configured for use in lwipopts.h */
+
+#include "lwip/udp.h"
+#include "lwip/mem.h"
+#include "lwip/memp.h"
+#include "lwip/dns.h"
+
+#include <string.h>
+
+/** DNS server IP address */
+#ifndef DNS_SERVER_ADDRESS
+#define DNS_SERVER_ADDRESS(ipaddr)        (ip4_addr_set_u32(ipaddr, ipaddr_addr("208.67.222.222"))) /* resolver1.opendns.com */
+#endif
+
+/** DNS server port address */
+#ifndef DNS_SERVER_PORT
+#define DNS_SERVER_PORT           53
+#endif
+
+/** DNS maximum number of retries when asking for a name, before "timeout". */
+#ifndef DNS_MAX_RETRIES
+#define DNS_MAX_RETRIES           4
+#endif
+
+/** DNS resource record max. TTL (one week as default) */
+#ifndef DNS_MAX_TTL
+#define DNS_MAX_TTL               604800
+#endif
+
+/* DNS protocol flags */
+#define DNS_FLAG1_RESPONSE        0x80
+#define DNS_FLAG1_OPCODE_STATUS   0x10
+#define DNS_FLAG1_OPCODE_INVERSE  0x08
+#define DNS_FLAG1_OPCODE_STANDARD 0x00
+#define DNS_FLAG1_AUTHORATIVE     0x04
+#define DNS_FLAG1_TRUNC           0x02
+#define DNS_FLAG1_RD              0x01
+#define DNS_FLAG2_RA              0x80
+#define DNS_FLAG2_ERR_MASK        0x0f
+#define DNS_FLAG2_ERR_NONE        0x00
+#define DNS_FLAG2_ERR_NAME        0x03
+
+/* DNS protocol states */
+#define DNS_STATE_UNUSED          0
+#define DNS_STATE_NEW             1
+#define DNS_STATE_ASKING          2
+#define DNS_STATE_DONE            3
+
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/bpstruct.h"
+#endif
+PACK_STRUCT_BEGIN
+/** DNS message header */
+struct dns_hdr {
+  PACK_STRUCT_FIELD(u16_t id);
+  PACK_STRUCT_FIELD(u8_t flags1);
+  PACK_STRUCT_FIELD(u8_t flags2);
+  PACK_STRUCT_FIELD(u16_t numquestions);
+  PACK_STRUCT_FIELD(u16_t numanswers);
+  PACK_STRUCT_FIELD(u16_t numauthrr);
+  PACK_STRUCT_FIELD(u16_t numextrarr);
+} PACK_STRUCT_STRUCT;
+PACK_STRUCT_END
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/epstruct.h"
+#endif
+#define SIZEOF_DNS_HDR 12
+
+/** DNS query message structure.
+    No packing needed: only used locally on the stack. */
+struct dns_query {
+  /* DNS query record starts with either a domain name or a pointer
+     to a name already present somewhere in the packet. */
+  u16_t type;
+  u16_t cls;
+};
+#define SIZEOF_DNS_QUERY 4
+
+/** DNS answer message structure.
+    No packing needed: only used locally on the stack. */
+struct dns_answer {
+  /* DNS answer record starts with either a domain name or a pointer
+     to a name already present somewhere in the packet. */
+  u16_t type;
+  u16_t cls;
+  u32_t ttl;
+  u16_t len;
+};
+#define SIZEOF_DNS_ANSWER 10
+
+/** DNS table entry */
+struct dns_table_entry {
+  u8_t  state;
+  u8_t  numdns;
+  u8_t  tmr;
+  u8_t  retries;
+  u8_t  seqno;
+  u8_t  err;
+  u32_t ttl;
+  char name[DNS_MAX_NAME_LENGTH];
+  ip_addr_t ipaddr;
+  /* pointer to callback on DNS query done */
+  dns_found_callback found;
+  void *arg;
+};
+
+#if DNS_LOCAL_HOSTLIST
+
+#if DNS_LOCAL_HOSTLIST_IS_DYNAMIC
+/** Local host-list. For hostnames in this list, no
+ *  external name resolution is performed */
+static struct local_hostlist_entry *local_hostlist_dynamic;
+#else /* DNS_LOCAL_HOSTLIST_IS_DYNAMIC */
+
+/** Defining this allows the local_hostlist_static to be placed in a different
+ * linker section (e.g. FLASH) */
+#ifndef DNS_LOCAL_HOSTLIST_STORAGE_PRE
+#define DNS_LOCAL_HOSTLIST_STORAGE_PRE static
+#endif /* DNS_LOCAL_HOSTLIST_STORAGE_PRE */
+/** Defining this allows the local_hostlist_static to be placed in a different
+ * linker section (e.g. FLASH) */
+#ifndef DNS_LOCAL_HOSTLIST_STORAGE_POST
+#define DNS_LOCAL_HOSTLIST_STORAGE_POST
+#endif /* DNS_LOCAL_HOSTLIST_STORAGE_POST */
+DNS_LOCAL_HOSTLIST_STORAGE_PRE struct local_hostlist_entry local_hostlist_static[]
+  DNS_LOCAL_HOSTLIST_STORAGE_POST = DNS_LOCAL_HOSTLIST_INIT;
+
+#endif /* DNS_LOCAL_HOSTLIST_IS_DYNAMIC */
+
+static void dns_init_local();
+#endif /* DNS_LOCAL_HOSTLIST */
+
+
+/* forward declarations */
+static void dns_recv(void *s, struct udp_pcb *pcb, struct pbuf *p, ip_addr_t *addr, u16_t port);
+static void dns_check_entries(void);
+
+/*-----------------------------------------------------------------------------
+ * Globales
+ *----------------------------------------------------------------------------*/
+
+/* DNS variables */
+static struct udp_pcb        *dns_pcb;
+static u8_t                   dns_seqno;
+static struct dns_table_entry dns_table[DNS_TABLE_SIZE];
+static ip_addr_t              dns_servers[DNS_MAX_SERVERS];
+/** Contiguous buffer for processing responses */
+static u8_t                   dns_payload_buffer[LWIP_MEM_ALIGN_BUFFER(DNS_MSG_SIZE)];
+static u8_t*                  dns_payload;
+
+/**
+ * Initialize the resolver: set up the UDP pcb and configure the default server
+ * (DNS_SERVER_ADDRESS).
+ */
+void
+dns_init()
+{
+  ip_addr_t dnsserver;
+
+  dns_payload = (u8_t *)LWIP_MEM_ALIGN(dns_payload_buffer);
+  
+  /* initialize default DNS server address */
+  DNS_SERVER_ADDRESS(&dnsserver);
+
+  LWIP_DEBUGF(DNS_DEBUG, ("dns_init: initializing\n"));
+
+  /* if dns client not yet initialized... */
+  if (dns_pcb == NULL) {
+    dns_pcb = udp_new();
+
+    if (dns_pcb != NULL) {
+      /* initialize DNS table not needed (initialized to zero since it is a
+       * global variable) */
+      LWIP_ASSERT("For implicit initialization to work, DNS_STATE_UNUSED needs to be 0",
+        DNS_STATE_UNUSED == 0);
+
+      /* initialize DNS client */
+      udp_bind(dns_pcb, IP_ADDR_ANY, 0);
+      udp_recv(dns_pcb, dns_recv, NULL);
+
+      /* initialize default DNS primary server */
+      dns_setserver(0, &dnsserver);
+    }
+  }
+#if DNS_LOCAL_HOSTLIST
+  dns_init_local();
+#endif
+}
+
+/**
+ * Initialize one of the DNS servers.
+ *
+ * @param numdns the index of the DNS server to set must be < DNS_MAX_SERVERS
+ * @param dnsserver IP address of the DNS server to set
+ */
+void
+dns_setserver(u8_t numdns, ip_addr_t *dnsserver)
+{
+  if ((numdns < DNS_MAX_SERVERS) && (dns_pcb != NULL) &&
+      (dnsserver != NULL) && !ip_addr_isany(dnsserver)) {
+    dns_servers[numdns] = (*dnsserver);
+  }
+}
+
+/**
+ * Obtain one of the currently configured DNS server.
+ *
+ * @param numdns the index of the DNS server
+ * @return IP address of the indexed DNS server or "ip_addr_any" if the DNS
+ *         server has not been configured.
+ */
+ip_addr_t
+dns_getserver(u8_t numdns)
+{
+  if (numdns < DNS_MAX_SERVERS) {
+    return dns_servers[numdns];
+  } else {
+    return *IP_ADDR_ANY;
+  }
+}
+
+/**
+ * The DNS resolver client timer - handle retries and timeouts and should
+ * be called every DNS_TMR_INTERVAL milliseconds (every second by default).
+ */
+void
+dns_tmr(void)
+{
+  if (dns_pcb != NULL) {
+    LWIP_DEBUGF(DNS_DEBUG, ("dns_tmr: dns_check_entries\n"));
+    dns_check_entries();
+  }
+}
+
+#if DNS_LOCAL_HOSTLIST
+static void
+dns_init_local()
+{
+#if DNS_LOCAL_HOSTLIST_IS_DYNAMIC && defined(DNS_LOCAL_HOSTLIST_INIT)
+  int i;
+  struct local_hostlist_entry *entry;
+  /* Dynamic: copy entries from DNS_LOCAL_HOSTLIST_INIT to list */
+  struct local_hostlist_entry local_hostlist_init[] = DNS_LOCAL_HOSTLIST_INIT;
+  size_t namelen;
+  for (i = 0; i < sizeof(local_hostlist_init) / sizeof(struct local_hostlist_entry); i++) {
+    struct local_hostlist_entry *init_entry = &local_hostlist_init[i];
+    LWIP_ASSERT("invalid host name (NULL)", init_entry->name != NULL);
+    namelen = strlen(init_entry->name);
+    LWIP_ASSERT("namelen <= DNS_LOCAL_HOSTLIST_MAX_NAMELEN", namelen <= DNS_LOCAL_HOSTLIST_MAX_NAMELEN);
+    entry = (struct local_hostlist_entry *)memp_malloc(MEMP_LOCALHOSTLIST);
+    LWIP_ASSERT("mem-error in dns_init_local", entry != NULL);
+    if (entry != NULL) {
+      entry->name = (char*)entry + sizeof(struct local_hostlist_entry);
+      MEMCPY((char*)entry->name, init_entry->name, namelen);
+      ((char*)entry->name)[namelen] = 0;
+      entry->addr = init_entry->addr;
+      entry->next = local_hostlist_dynamic;
+      local_hostlist_dynamic = entry;
+    }
+  }
+#endif /* DNS_LOCAL_HOSTLIST_IS_DYNAMIC && defined(DNS_LOCAL_HOSTLIST_INIT) */
+}
+
+/**
+ * Scans the local host-list for a hostname.
+ *
+ * @param hostname Hostname to look for in the local host-list
+ * @return The first IP address for the hostname in the local host-list or
+ *         IPADDR_NONE if not found.
+ */
+static u32_t
+dns_lookup_local(const char *hostname)
+{
+#if DNS_LOCAL_HOSTLIST_IS_DYNAMIC
+  struct local_hostlist_entry *entry = local_hostlist_dynamic;
+  while(entry != NULL) {
+    if(strcmp(entry->name, hostname) == 0) {
+      return ip4_addr_get_u32(&entry->addr);
+    }
+    entry = entry->next;
+  }
+#else /* DNS_LOCAL_HOSTLIST_IS_DYNAMIC */
+  int i;
+  for (i = 0; i < sizeof(local_hostlist_static) / sizeof(struct local_hostlist_entry); i++) {
+    if(strcmp(local_hostlist_static[i].name, hostname) == 0) {
+      return ip4_addr_get_u32(&local_hostlist_static[i].addr);
+    }
+  }
+#endif /* DNS_LOCAL_HOSTLIST_IS_DYNAMIC */
+  return IPADDR_NONE;
+}
+
+#if DNS_LOCAL_HOSTLIST_IS_DYNAMIC
+/** Remove all entries from the local host-list for a specific hostname
+ * and/or IP addess
+ *
+ * @param hostname hostname for which entries shall be removed from the local
+ *                 host-list
+ * @param addr address for which entries shall be removed from the local host-list
+ * @return the number of removed entries
+ */
+int
+dns_local_removehost(const char *hostname, const ip_addr_t *addr)
+{
+  int removed = 0;
+  struct local_hostlist_entry *entry = local_hostlist_dynamic;
+  struct local_hostlist_entry *last_entry = NULL;
+  while (entry != NULL) {
+    if (((hostname == NULL) || !strcmp(entry->name, hostname)) &&
+        ((addr == NULL) || ip_addr_cmp(&entry->addr, addr))) {
+      struct local_hostlist_entry *free_entry;
+      if (last_entry != NULL) {
+        last_entry->next = entry->next;
+      } else {
+        local_hostlist_dynamic = entry->next;
+      }
+      free_entry = entry;
+      entry = entry->next;
+      memp_free(MEMP_LOCALHOSTLIST, free_entry);
+      removed++;
+    } else {
+      last_entry = entry;
+      entry = entry->next;
+    }
+  }
+  return removed;
+}
+
+/**
+ * Add a hostname/IP address pair to the local host-list.
+ * Duplicates are not checked.
+ *
+ * @param hostname hostname of the new entry
+ * @param addr IP address of the new entry
+ * @return ERR_OK if succeeded or ERR_MEM on memory error
+ */
+err_t
+dns_local_addhost(const char *hostname, const ip_addr_t *addr)
+{
+  struct local_hostlist_entry *entry;
+  size_t namelen;
+  LWIP_ASSERT("invalid host name (NULL)", hostname != NULL);
+  namelen = strlen(hostname);
+  LWIP_ASSERT("namelen <= DNS_LOCAL_HOSTLIST_MAX_NAMELEN", namelen <= DNS_LOCAL_HOSTLIST_MAX_NAMELEN);
+  entry = (struct local_hostlist_entry *)memp_malloc(MEMP_LOCALHOSTLIST);
+  if (entry == NULL) {
+    return ERR_MEM;
+  }
+  entry->name = (char*)entry + sizeof(struct local_hostlist_entry);
+  MEMCPY((char*)entry->name, hostname, namelen);
+  ((char*)entry->name)[namelen] = 0;
+  ip_addr_copy(entry->addr, *addr);
+  entry->next = local_hostlist_dynamic;
+  local_hostlist_dynamic = entry;
+  return ERR_OK;
+}
+#endif /* DNS_LOCAL_HOSTLIST_IS_DYNAMIC*/
+#endif /* DNS_LOCAL_HOSTLIST */
+
+/**
+ * Look up a hostname in the array of known hostnames.
+ *
+ * @note This function only looks in the internal array of known
+ * hostnames, it does not send out a query for the hostname if none
+ * was found. The function dns_enqueue() can be used to send a query
+ * for a hostname.
+ *
+ * @param name the hostname to look up
+ * @return the hostname's IP address, as u32_t (instead of ip_addr_t to
+ *         better check for failure: != IPADDR_NONE) or IPADDR_NONE if the hostname
+ *         was not found in the cached dns_table.
+ */
+static u32_t
+dns_lookup(const char *name)
+{
+  u8_t i;
+#if DNS_LOCAL_HOSTLIST || defined(DNS_LOOKUP_LOCAL_EXTERN)
+  u32_t addr;
+#endif /* DNS_LOCAL_HOSTLIST || defined(DNS_LOOKUP_LOCAL_EXTERN) */
+#if DNS_LOCAL_HOSTLIST
+  if ((addr = dns_lookup_local(name)) != IPADDR_NONE) {
+    return addr;
+  }
+#endif /* DNS_LOCAL_HOSTLIST */
+#ifdef DNS_LOOKUP_LOCAL_EXTERN
+  if((addr = DNS_LOOKUP_LOCAL_EXTERN(name)) != IPADDR_NONE) {
+    return addr;
+  }
+#endif /* DNS_LOOKUP_LOCAL_EXTERN */
+
+  /* Walk through name list, return entry if found. If not, return NULL. */
+  for (i = 0; i < DNS_TABLE_SIZE; ++i) {
+    if ((dns_table[i].state == DNS_STATE_DONE) &&
+        (strcmp(name, dns_table[i].name) == 0)) {
+      LWIP_DEBUGF(DNS_DEBUG, ("dns_lookup: \"%s\": found = ", name));
+      ip_addr_debug_print(DNS_DEBUG, &(dns_table[i].ipaddr));
+      LWIP_DEBUGF(DNS_DEBUG, ("\n"));
+      return ip4_addr_get_u32(&dns_table[i].ipaddr);
+    }
+  }
+
+  return IPADDR_NONE;
+}
+
+#if DNS_DOES_NAME_CHECK
+/**
+ * Compare the "dotted" name "query" with the encoded name "response"
+ * to make sure an answer from the DNS server matches the current dns_table
+ * entry (otherwise, answers might arrive late for hostname not on the list
+ * any more).
+ *
+ * @param query hostname (not encoded) from the dns_table
+ * @param response encoded hostname in the DNS response
+ * @return 0: names equal; 1: names differ
+ */
+static u8_t
+dns_compare_name(unsigned char *query, unsigned char *response)
+{
+  unsigned char n;
+
+  do {
+    n = *response++;
+    /** @see RFC 1035 - 4.1.4. Message compression */
+    if ((n & 0xc0) == 0xc0) {
+      /* Compressed name */
+      break;
+    } else {
+      /* Not compressed name */
+      while (n > 0) {
+        if ((*query) != (*response)) {
+          return 1;
+        }
+        ++response;
+        ++query;
+        --n;
+      };
+      ++query;
+    }
+  } while (*response != 0);
+
+  return 0;
+}
+#endif /* DNS_DOES_NAME_CHECK */
+
+/**
+ * Walk through a compact encoded DNS name and return the end of the name.
+ *
+ * @param query encoded DNS name in the DNS server response
+ * @return end of the name
+ */
+static unsigned char *
+dns_parse_name(unsigned char *query)
+{
+  unsigned char n;
+
+  do {
+    n = *query++;
+    /** @see RFC 1035 - 4.1.4. Message compression */
+    if ((n & 0xc0) == 0xc0) {
+      /* Compressed name */
+      break;
+    } else {
+      /* Not compressed name */
+      while (n > 0) {
+        ++query;
+        --n;
+      };
+    }
+  } while (*query != 0);
+
+  return query + 1;
+}
+
+/**
+ * Send a DNS query packet.
+ *
+ * @param numdns index of the DNS server in the dns_servers table
+ * @param name hostname to query
+ * @param id index of the hostname in dns_table, used as transaction ID in the
+ *        DNS query packet
+ * @return ERR_OK if packet is sent; an err_t indicating the problem otherwise
+ */
+static err_t
+dns_send(u8_t numdns, const char* name, u8_t id)
+{
+  err_t err;
+  struct dns_hdr *hdr;
+  struct dns_query qry;
+  struct pbuf *p;
+  char *query, *nptr;
+  const char *pHostname;
+  u8_t n;
+
+  LWIP_DEBUGF(DNS_DEBUG, ("dns_send: dns_servers[%"U16_F"] \"%s\": request\n",
+              (u16_t)(numdns), name));
+  LWIP_ASSERT("dns server out of array", numdns < DNS_MAX_SERVERS);
+  LWIP_ASSERT("dns server has no IP address set", !ip_addr_isany(&dns_servers[numdns]));
+
+  /* if here, we have either a new query or a retry on a previous query to process */
+  p = pbuf_alloc(PBUF_TRANSPORT, SIZEOF_DNS_HDR + DNS_MAX_NAME_LENGTH +
+                 SIZEOF_DNS_QUERY, PBUF_RAM);
+  if (p != NULL) {
+    LWIP_ASSERT("pbuf must be in one piece", p->next == NULL);
+    /* fill dns header */
+    hdr = (struct dns_hdr*)p->payload;
+    memset(hdr, 0, SIZEOF_DNS_HDR);
+    hdr->id = htons(id);
+    hdr->flags1 = DNS_FLAG1_RD;
+    hdr->numquestions = PP_HTONS(1);
+    query = (char*)hdr + SIZEOF_DNS_HDR;
+    pHostname = name;
+    --pHostname;
+
+    /* convert hostname into suitable query format. */
+    do {
+      ++pHostname;
+      nptr = query;
+      ++query;
+      for(n = 0; *pHostname != '.' && *pHostname != 0; ++pHostname) {
+        *query = *pHostname;
+        ++query;
+        ++n;
+      }
+      *nptr = n;
+    } while(*pHostname != 0);
+    *query++='\0';
+
+    /* fill dns query */
+    qry.type = PP_HTONS(DNS_RRTYPE_A);
+    qry.cls = PP_HTONS(DNS_RRCLASS_IN);
+    SMEMCPY(query, &qry, SIZEOF_DNS_QUERY);
+
+    /* resize pbuf to the exact dns query */
+    pbuf_realloc(p, (u16_t)((query + SIZEOF_DNS_QUERY) - ((char*)(p->payload))));
+
+    /* connect to the server for faster receiving */
+    udp_connect(dns_pcb, &dns_servers[numdns], DNS_SERVER_PORT);
+    /* send dns packet */
+    err = udp_sendto(dns_pcb, p, &dns_servers[numdns], DNS_SERVER_PORT);
+
+    /* free pbuf */
+    pbuf_free(p);
+  } else {
+    err = ERR_MEM;
+  }
+
+  return err;
+}
+
+/**
+ * dns_check_entry() - see if pEntry has not yet been queried and, if so, sends out a query.
+ * Check an entry in the dns_table:
+ * - send out query for new entries
+ * - retry old pending entries on timeout (also with different servers)
+ * - remove completed entries from the table if their TTL has expired
+ *
+ * @param i index of the dns_table entry to check
+ */
+static void
+dns_check_entry(u8_t i)
+{
+  err_t err;
+  struct dns_table_entry *pEntry = &dns_table[i];
+
+  LWIP_ASSERT("array index out of bounds", i < DNS_TABLE_SIZE);
+
+  switch(pEntry->state) {
+
+    case DNS_STATE_NEW: {
+      /* initialize new entry */
+      pEntry->state   = DNS_STATE_ASKING;
+      pEntry->numdns  = 0;
+      pEntry->tmr     = 1;
+      pEntry->retries = 0;
+      
+      /* send DNS packet for this entry */
+      err = dns_send(pEntry->numdns, pEntry->name, i);
+      if (err != ERR_OK) {
+        LWIP_DEBUGF(DNS_DEBUG | LWIP_DBG_LEVEL_WARNING,
+                    ("dns_send returned error: %d\n", err)); //FIX DG, lwip_strerr is part of lwip/api
+      }
+      break;
+    }
+
+    case DNS_STATE_ASKING: {
+      if (--pEntry->tmr == 0) {
+        if (++pEntry->retries == DNS_MAX_RETRIES) {
+          if ((pEntry->numdns+1<DNS_MAX_SERVERS) && !ip_addr_isany(&dns_servers[pEntry->numdns+1])) {
+            /* change of server */
+            pEntry->numdns++;
+            pEntry->tmr     = 1;
+            pEntry->retries = 0;
+            break;
+          } else {
+            LWIP_DEBUGF(DNS_DEBUG, ("dns_check_entry: \"%s\": timeout\n", pEntry->name));
+            /* call specified callback function if provided */
+            if (pEntry->found)
+              (*pEntry->found)(pEntry->name, NULL, pEntry->arg);
+            /* flush this entry */
+            pEntry->state   = DNS_STATE_UNUSED;
+            pEntry->found   = NULL;
+            break;
+          }
+        }
+
+        /* wait longer for the next retry */
+        pEntry->tmr = pEntry->retries;
+
+        /* send DNS packet for this entry */
+        err = dns_send(pEntry->numdns, pEntry->name, i);
+        if (err != ERR_OK) {
+          LWIP_DEBUGF(DNS_DEBUG | LWIP_DBG_LEVEL_WARNING,
+                      ("dns_send returned error: %d\n", err)); //FIX DG, lwip_strerr is part of lwip/api
+        }
+      }
+      break;
+    }
+
+    case DNS_STATE_DONE: {
+      /* if the time to live is nul */
+      if (--pEntry->ttl == 0) {
+        LWIP_DEBUGF(DNS_DEBUG, ("dns_check_entry: \"%s\": flush\n", pEntry->name));
+        /* flush this entry */
+        pEntry->state = DNS_STATE_UNUSED;
+        pEntry->found = NULL;
+      }
+      break;
+    }
+    case DNS_STATE_UNUSED:
+      /* nothing to do */
+      break;
+    default:
+      LWIP_ASSERT("unknown dns_table entry state:", 0);
+      break;
+  }
+}
+
+/**
+ * Call dns_check_entry for each entry in dns_table - check all entries.
+ */
+static void
+dns_check_entries(void)
+{
+  u8_t i;
+
+  for (i = 0; i < DNS_TABLE_SIZE; ++i) {
+    dns_check_entry(i);
+  }
+}
+
+/**
+ * Receive input function for DNS response packets arriving for the dns UDP pcb.
+ *
+ * @params see udp.h
+ */
+static void
+dns_recv(void *arg, struct udp_pcb *pcb, struct pbuf *p, ip_addr_t *addr, u16_t port)
+{
+  u16_t i;
+  char *pHostname;
+  struct dns_hdr *hdr;
+  struct dns_answer ans;
+  struct dns_table_entry *pEntry;
+  u16_t nquestions, nanswers;
+
+  LWIP_UNUSED_ARG(arg);
+  LWIP_UNUSED_ARG(pcb);
+  LWIP_UNUSED_ARG(addr);
+  LWIP_UNUSED_ARG(port);
+
+  /* is the dns message too big ? */
+  if (p->tot_len > DNS_MSG_SIZE) {
+    LWIP_DEBUGF(DNS_DEBUG, ("dns_recv: pbuf too big\n"));
+    /* free pbuf and return */
+    goto memerr;
+  }
+
+  /* is the dns message big enough ? */
+  if (p->tot_len < (SIZEOF_DNS_HDR + SIZEOF_DNS_QUERY + SIZEOF_DNS_ANSWER)) {
+    LWIP_DEBUGF(DNS_DEBUG, ("dns_recv: pbuf too small\n"));
+    /* free pbuf and return */
+    goto memerr;
+  }
+
+  /* copy dns payload inside static buffer for processing */ 
+  if (pbuf_copy_partial(p, dns_payload, p->tot_len, 0) == p->tot_len) {
+    /* The ID in the DNS header should be our entry into the name table. */
+    hdr = (struct dns_hdr*)dns_payload;
+    i = htons(hdr->id);
+    if (i < DNS_TABLE_SIZE) {
+      pEntry = &dns_table[i];
+      if(pEntry->state == DNS_STATE_ASKING) {
+        /* This entry is now completed. */
+        pEntry->state = DNS_STATE_DONE;
+        pEntry->err   = hdr->flags2 & DNS_FLAG2_ERR_MASK;
+
+        /* We only care about the question(s) and the answers. The authrr
+           and the extrarr are simply discarded. */
+        nquestions = htons(hdr->numquestions);
+        nanswers   = htons(hdr->numanswers);
+
+        /* Check for error. If so, call callback to inform. */
+        if (((hdr->flags1 & DNS_FLAG1_RESPONSE) == 0) || (pEntry->err != 0) || (nquestions != 1)) {
+          LWIP_DEBUGF(DNS_DEBUG, ("dns_recv: \"%s\": error in flags\n", pEntry->name));
+          /* call callback to indicate error, clean up memory and return */
+          goto responseerr;
+        }
+
+#if DNS_DOES_NAME_CHECK
+        /* Check if the name in the "question" part match with the name in the entry. */
+        if (dns_compare_name((unsigned char *)(pEntry->name), (unsigned char *)dns_payload + SIZEOF_DNS_HDR) != 0) {
+          LWIP_DEBUGF(DNS_DEBUG, ("dns_recv: \"%s\": response not match to query\n", pEntry->name));
+          /* call callback to indicate error, clean up memory and return */
+          goto responseerr;
+        }
+#endif /* DNS_DOES_NAME_CHECK */
+
+        /* Skip the name in the "question" part */
+        pHostname = (char *) dns_parse_name((unsigned char *)dns_payload + SIZEOF_DNS_HDR) + SIZEOF_DNS_QUERY;
+
+        while (nanswers > 0) {
+          /* skip answer resource record's host name */
+          pHostname = (char *) dns_parse_name((unsigned char *)pHostname);
+
+          /* Check for IP address type and Internet class. Others are discarded. */
+          SMEMCPY(&ans, pHostname, SIZEOF_DNS_ANSWER);
+          if((ans.type == PP_HTONS(DNS_RRTYPE_A)) && (ans.cls == PP_HTONS(DNS_RRCLASS_IN)) &&
+             (ans.len == PP_HTONS(sizeof(ip_addr_t))) ) {
+            /* read the answer resource record's TTL, and maximize it if needed */
+            pEntry->ttl = ntohl(ans.ttl);
+            if (pEntry->ttl > DNS_MAX_TTL) {
+              pEntry->ttl = DNS_MAX_TTL;
+            }
+            /* read the IP address after answer resource record's header */
+            SMEMCPY(&(pEntry->ipaddr), (pHostname+SIZEOF_DNS_ANSWER), sizeof(ip_addr_t));
+            LWIP_DEBUGF(DNS_DEBUG, ("dns_recv: \"%s\": response = ", pEntry->name));
+            ip_addr_debug_print(DNS_DEBUG, (&(pEntry->ipaddr)));
+            LWIP_DEBUGF(DNS_DEBUG, ("\n"));
+            /* call specified callback function if provided */
+            if (pEntry->found) {
+              (*pEntry->found)(pEntry->name, &pEntry->ipaddr, pEntry->arg);
+            }
+            /* deallocate memory and return */
+            goto memerr;
+          } else {
+            pHostname = pHostname + SIZEOF_DNS_ANSWER + htons(ans.len);
+          }
+          --nanswers;
+        }
+        LWIP_DEBUGF(DNS_DEBUG, ("dns_recv: \"%s\": error in response\n", pEntry->name));
+        /* call callback to indicate error, clean up memory and return */
+        goto responseerr;
+      }
+    }
+  }
+
+  /* deallocate memory and return */
+  goto memerr;
+
+responseerr:
+  /* ERROR: call specified callback function with NULL as name to indicate an error */
+  if (pEntry->found) {
+    (*pEntry->found)(pEntry->name, NULL, pEntry->arg);
+  }
+  /* flush this entry */
+  pEntry->state = DNS_STATE_UNUSED;
+  pEntry->found = NULL;
+
+memerr:
+  /* free pbuf */
+  pbuf_free(p);
+  return;
+}
+
+/**
+ * Queues a new hostname to resolve and sends out a DNS query for that hostname
+ *
+ * @param name the hostname that is to be queried
+ * @param found a callback founction to be called on success, failure or timeout
+ * @param callback_arg argument to pass to the callback function
+ * @return @return a err_t return code.
+ */
+static err_t
+dns_enqueue(const char *name, dns_found_callback found, void *callback_arg)
+{
+  u8_t i;
+  u8_t lseq, lseqi;
+  struct dns_table_entry *pEntry = NULL;
+  size_t namelen;
+
+  /* search an unused entry, or the oldest one */
+  lseq = lseqi = 0;
+  for (i = 0; i < DNS_TABLE_SIZE; ++i) {
+    pEntry = &dns_table[i];
+    /* is it an unused entry ? */
+    if (pEntry->state == DNS_STATE_UNUSED)
+      break;
+
+    /* check if this is the oldest completed entry */
+    if (pEntry->state == DNS_STATE_DONE) {
+      if ((dns_seqno - pEntry->seqno) > lseq) {
+        lseq = dns_seqno - pEntry->seqno;
+        lseqi = i;
+      }
+    }
+  }
+
+  /* if we don't have found an unused entry, use the oldest completed one */
+  if (i == DNS_TABLE_SIZE) {
+    if ((lseqi >= DNS_TABLE_SIZE) || (dns_table[lseqi].state != DNS_STATE_DONE)) {
+      /* no entry can't be used now, table is full */
+      LWIP_DEBUGF(DNS_DEBUG, ("dns_enqueue: \"%s\": DNS entries table is full\n", name));
+      return ERR_MEM;
+    } else {
+      /* use the oldest completed one */
+      i = lseqi;
+      pEntry = &dns_table[i];
+    }
+  }
+
+  /* use this entry */
+  LWIP_DEBUGF(DNS_DEBUG, ("dns_enqueue: \"%s\": use DNS entry %"U16_F"\n", name, (u16_t)(i)));
+
+  /* fill the entry */
+  pEntry->state = DNS_STATE_NEW;
+  pEntry->seqno = dns_seqno++;
+  pEntry->found = found;
+  pEntry->arg   = callback_arg;
+  namelen = LWIP_MIN(strlen(name), DNS_MAX_NAME_LENGTH-1);
+  MEMCPY(pEntry->name, name, namelen);
+  pEntry->name[namelen] = 0;
+
+  /* force to send query without waiting timer */
+  dns_check_entry(i);
+
+  /* dns query is enqueued */
+  return ERR_INPROGRESS;
+}
+
+/**
+ * Resolve a hostname (string) into an IP address.
+ * NON-BLOCKING callback version for use with raw API!!!
+ *
+ * Returns immediately with one of err_t return codes:
+ * - ERR_OK if hostname is a valid IP address string or the host
+ *   name is already in the local names table.
+ * - ERR_INPROGRESS enqueue a request to be sent to the DNS server
+ *   for resolution if no errors are present.
+ *
+ * @param hostname the hostname that is to be queried
+ * @param addr pointer to a ip_addr_t where to store the address if it is already
+ *             cached in the dns_table (only valid if ERR_OK is returned!)
+ * @param found a callback function to be called on success, failure or timeout (only if
+ *              ERR_INPROGRESS is returned!)
+ * @param callback_arg argument to pass to the callback function
+ * @return a err_t return code.
+ */
+err_t
+dns_gethostbyname(const char *hostname, ip_addr_t *addr, dns_found_callback found,
+                  void *callback_arg)
+{
+  u32_t ipaddr;
+  /* not initialized or no valid server yet, or invalid addr pointer
+   * or invalid hostname or invalid hostname length */
+  if ((dns_pcb == NULL) || (addr == NULL) ||
+      (!hostname) || (!hostname[0]) ||
+      (strlen(hostname) >= DNS_MAX_NAME_LENGTH)) {
+    return ERR_VAL;
+  }
+
+#if LWIP_HAVE_LOOPIF
+  if (strcmp(hostname, "localhost")==0) {
+    ip_addr_set_loopback(addr);
+    return ERR_OK;
+  }
+#endif /* LWIP_HAVE_LOOPIF */
+
+  /* host name already in octet notation? set ip addr and return ERR_OK */
+  ipaddr = ipaddr_addr(hostname);
+  if (ipaddr == IPADDR_NONE) {
+    /* already have this address cached? */
+    ipaddr = dns_lookup(hostname);
+  }
+  if (ipaddr != IPADDR_NONE) {
+    ip4_addr_set_u32(addr, ipaddr);
+    return ERR_OK;
+  }
+
+  /* queue query with specified callback */
+  return dns_enqueue(hostname, found, callback_arg);
+}
+
+#endif /* LWIP_DNS */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/core/init.c	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,303 @@
+/**
+ * @file
+ * Modules initialization
+ *
+ */
+
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+
+#include "lwip/opt.h"
+
+#include "lwip/init.h"
+#include "lwip/stats.h"
+#include "lwip/sys.h"
+#include "lwip/mem.h"
+#include "lwip/memp.h"
+#include "lwip/pbuf.h"
+#include "lwip/netif.h"
+#include "lwip/sockets.h"
+#include "lwip/ip.h"
+#include "lwip/raw.h"
+#include "lwip/udp.h"
+#include "lwip/tcp_impl.h"
+#include "lwip/snmp_msg.h"
+#include "lwip/autoip.h"
+#include "lwip/igmp.h"
+#include "lwip/dns.h"
+#include "lwip/timers.h"
+#include "netif/etharp.h"
+
+/* Compile-time sanity checks for configuration errors.
+ * These can be done independently of LWIP_DEBUG, without penalty.
+ */
+#ifndef BYTE_ORDER
+  #error "BYTE_ORDER is not defined, you have to define it in your cc.h"
+#endif
+#if (!IP_SOF_BROADCAST && IP_SOF_BROADCAST_RECV)
+  #error "If you want to use broadcast filter per pcb on recv operations, you have to define IP_SOF_BROADCAST=1 in your lwipopts.h"
+#endif
+#if (!LWIP_ARP && ARP_QUEUEING)
+  #error "If you want to use ARP Queueing, you have to define LWIP_ARP=1 in your lwipopts.h"
+#endif
+#if (!LWIP_UDP && LWIP_UDPLITE)
+  #error "If you want to use UDP Lite, you have to define LWIP_UDP=1 in your lwipopts.h"
+#endif
+#if (!LWIP_UDP && LWIP_SNMP)
+  #error "If you want to use SNMP, you have to define LWIP_UDP=1 in your lwipopts.h"
+#endif
+#if (!LWIP_UDP && LWIP_DHCP)
+  #error "If you want to use DHCP, you have to define LWIP_UDP=1 in your lwipopts.h"
+#endif
+#if (!LWIP_UDP && LWIP_IGMP)
+  #error "If you want to use IGMP, you have to define LWIP_UDP=1 in your lwipopts.h"
+#endif
+#if (!LWIP_UDP && LWIP_SNMP)
+  #error "If you want to use SNMP, you have to define LWIP_UDP=1 in your lwipopts.h"
+#endif
+#if (!LWIP_UDP && LWIP_DNS)
+  #error "If you want to use DNS, you have to define LWIP_UDP=1 in your lwipopts.h"
+#endif
+#if (LWIP_ARP && ARP_QUEUEING && (MEMP_NUM_ARP_QUEUE<=0))
+  #error "If you want to use ARP Queueing, you have to define MEMP_NUM_ARP_QUEUE>=1 in your lwipopts.h"
+#endif
+#if (LWIP_RAW && (MEMP_NUM_RAW_PCB<=0))
+  #error "If you want to use RAW, you have to define MEMP_NUM_RAW_PCB>=1 in your lwipopts.h"
+#endif
+#if (LWIP_UDP && (MEMP_NUM_UDP_PCB<=0))
+  #error "If you want to use UDP, you have to define MEMP_NUM_UDP_PCB>=1 in your lwipopts.h"
+#endif
+#if (LWIP_TCP && (MEMP_NUM_TCP_PCB<=0))
+  #error "If you want to use TCP, you have to define MEMP_NUM_TCP_PCB>=1 in your lwipopts.h"
+#endif
+#if (LWIP_TCP && (TCP_WND > 0xffff))
+  #error "If you want to use TCP, TCP_WND must fit in an u16_t, so, you have to reduce it in your lwipopts.h"
+#endif
+#if (LWIP_TCP && (TCP_SND_QUEUELEN > 0xffff))
+  #error "If you want to use TCP, TCP_SND_QUEUELEN must fit in an u16_t, so, you have to reduce it in your lwipopts.h"
+#endif
+#if (LWIP_TCP && ((TCP_MAXRTX > 12) || (TCP_SYNMAXRTX > 12)))
+  #error "If you want to use TCP, TCP_MAXRTX and TCP_SYNMAXRTX must less or equal to 12 (due to tcp_backoff table), so, you have to reduce them in your lwipopts.h"
+#endif
+#if (LWIP_TCP && TCP_LISTEN_BACKLOG && (TCP_DEFAULT_LISTEN_BACKLOG < 0) || (TCP_DEFAULT_LISTEN_BACKLOG > 0xff))
+  #error "If you want to use TCP backlog, TCP_DEFAULT_LISTEN_BACKLOG must fit into an u8_t"
+#endif
+#if (LWIP_IGMP && (MEMP_NUM_IGMP_GROUP<=1))
+  #error "If you want to use IGMP, you have to define MEMP_NUM_IGMP_GROUP>1 in your lwipopts.h"
+#endif
+#if (LWIP_NETIF_API && (NO_SYS==1))
+  #error "If you want to use NETIF API, you have to define NO_SYS=0 in your lwipopts.h"
+#endif
+#if ((LWIP_SOCKET || LWIP_NETCONN) && (NO_SYS==1))
+  #error "If you want to use Sequential API, you have to define NO_SYS=0 in your lwipopts.h"
+#endif
+#if ((LWIP_NETCONN || LWIP_SOCKET) && (MEMP_NUM_TCPIP_MSG_API<=0))
+  #error "If you want to use Sequential API, you have to define MEMP_NUM_TCPIP_MSG_API>=1 in your lwipopts.h"
+#endif
+#if (!LWIP_NETCONN && LWIP_SOCKET)
+  #error "If you want to use Socket API, you have to define LWIP_NETCONN=1 in your lwipopts.h"
+#endif
+#if (((!LWIP_DHCP) || (!LWIP_AUTOIP)) && LWIP_DHCP_AUTOIP_COOP)
+  #error "If you want to use DHCP/AUTOIP cooperation mode, you have to define LWIP_DHCP=1 and LWIP_AUTOIP=1 in your lwipopts.h"
+#endif
+#if (((!LWIP_DHCP) || (!LWIP_ARP)) && DHCP_DOES_ARP_CHECK)
+  #error "If you want to use DHCP ARP checking, you have to define LWIP_DHCP=1 and LWIP_ARP=1 in your lwipopts.h"
+#endif
+#if (!LWIP_ARP && LWIP_AUTOIP)
+  #error "If you want to use AUTOIP, you have to define LWIP_ARP=1 in your lwipopts.h"
+#endif
+#if (LWIP_SNMP && (SNMP_CONCURRENT_REQUESTS<=0))
+  #error "If you want to use SNMP, you have to define SNMP_CONCURRENT_REQUESTS>=1 in your lwipopts.h"
+#endif
+#if (LWIP_SNMP && (SNMP_TRAP_DESTINATIONS<=0))
+  #error "If you want to use SNMP, you have to define SNMP_TRAP_DESTINATIONS>=1 in your lwipopts.h"
+#endif
+#if (LWIP_TCP && ((LWIP_EVENT_API && LWIP_CALLBACK_API) || (!LWIP_EVENT_API && !LWIP_CALLBACK_API)))
+  #error "One and exactly one of LWIP_EVENT_API and LWIP_CALLBACK_API has to be enabled in your lwipopts.h"
+#endif
+/* There must be sufficient timeouts, taking into account requirements of the subsystems. */
+#if LWIP_TIMERS && (MEMP_NUM_SYS_TIMEOUT < (LWIP_TCP + IP_REASSEMBLY + LWIP_ARP + (2*LWIP_DHCP) + LWIP_AUTOIP + LWIP_IGMP + LWIP_DNS + PPP_SUPPORT))
+  #error "MEMP_NUM_SYS_TIMEOUT is too low to accomodate all required timeouts"
+#endif
+#if (IP_REASSEMBLY && (MEMP_NUM_REASSDATA > IP_REASS_MAX_PBUFS))
+  #error "MEMP_NUM_REASSDATA > IP_REASS_MAX_PBUFS doesn't make sense since each struct ip_reassdata must hold 2 pbufs at least!"
+#endif
+#if (MEM_LIBC_MALLOC && MEM_USE_POOLS)
+  #error "MEM_LIBC_MALLOC and MEM_USE_POOLS may not both be simultaneously enabled in your lwipopts.h"
+#endif
+#if (MEM_USE_POOLS && !MEMP_USE_CUSTOM_POOLS)
+  #error "MEM_USE_POOLS requires custom pools (MEMP_USE_CUSTOM_POOLS) to be enabled in your lwipopts.h"
+#endif
+#if (PBUF_POOL_BUFSIZE <= MEM_ALIGNMENT)
+  #error "PBUF_POOL_BUFSIZE must be greater than MEM_ALIGNMENT or the offset may take the full first pbuf"
+#endif
+#if (TCP_QUEUE_OOSEQ && !LWIP_TCP)
+  #error "TCP_QUEUE_OOSEQ requires LWIP_TCP"
+#endif
+#if (DNS_LOCAL_HOSTLIST && !DNS_LOCAL_HOSTLIST_IS_DYNAMIC && !(defined(DNS_LOCAL_HOSTLIST_INIT)))
+  #error "you have to define define DNS_LOCAL_HOSTLIST_INIT {{'host1', 0x123}, {'host2', 0x234}} to initialize DNS_LOCAL_HOSTLIST"
+#endif
+#if PPP_SUPPORT && !PPPOS_SUPPORT & !PPPOE_SUPPORT
+  #error "PPP_SUPPORT needs either PPPOS_SUPPORT or PPPOE_SUPPORT turned on"
+#endif
+#if !LWIP_ETHERNET && (LWIP_ARP || PPPOE_SUPPORT)
+  #error "LWIP_ETHERNET needs to be turned on for LWIP_ARP or PPPOE_SUPPORT"
+#endif
+#if LWIP_IGMP && !defined(LWIP_RAND)
+  #error "When using IGMP, LWIP_RAND() needs to be defined to a random-function returning an u32_t random value"
+#endif
+#if LWIP_TCPIP_CORE_LOCKING_INPUT && !LWIP_TCPIP_CORE_LOCKING
+  #error "When using LWIP_TCPIP_CORE_LOCKING_INPUT, LWIP_TCPIP_CORE_LOCKING must be enabled, too"
+#endif
+#if LWIP_TCP && LWIP_NETIF_TX_SINGLE_PBUF && !TCP_OVERSIZE
+  #error "LWIP_NETIF_TX_SINGLE_PBUF needs TCP_OVERSIZE enabled to create single-pbuf TCP packets"
+#endif
+#if IP_FRAG && IP_FRAG_USES_STATIC_BUF && LWIP_NETIF_TX_SINGLE_PBUF
+  #error "LWIP_NETIF_TX_SINGLE_PBUF does not work with IP_FRAG_USES_STATIC_BUF==1 as that creates pbuf queues"
+#endif
+
+
+/* Compile-time checks for deprecated options.
+ */
+#ifdef MEMP_NUM_TCPIP_MSG
+  #error "MEMP_NUM_TCPIP_MSG option is deprecated. Remove it from your lwipopts.h."
+#endif
+#ifdef MEMP_NUM_API_MSG
+  #error "MEMP_NUM_API_MSG option is deprecated. Remove it from your lwipopts.h."
+#endif
+#ifdef TCP_REXMIT_DEBUG
+  #error "TCP_REXMIT_DEBUG option is deprecated. Remove it from your lwipopts.h."
+#endif
+#ifdef RAW_STATS
+  #error "RAW_STATS option is deprecated. Remove it from your lwipopts.h."
+#endif
+#ifdef ETHARP_QUEUE_FIRST
+  #error "ETHARP_QUEUE_FIRST option is deprecated. Remove it from your lwipopts.h."
+#endif
+#ifdef ETHARP_ALWAYS_INSERT
+  #error "ETHARP_ALWAYS_INSERT option is deprecated. Remove it from your lwipopts.h."
+#endif
+
+#ifdef LWIP_DEBUG
+static void
+lwip_sanity_check(void)
+{
+  /* Warnings */
+#if LWIP_NETCONN
+  if (MEMP_NUM_NETCONN > (MEMP_NUM_TCP_PCB+MEMP_NUM_TCP_PCB_LISTEN+MEMP_NUM_UDP_PCB+MEMP_NUM_RAW_PCB))
+    LWIP_PLATFORM_DIAG(("lwip_sanity_check: WARNING: MEMP_NUM_NETCONN should be less than the sum of MEMP_NUM_{TCP,RAW,UDP}_PCB+MEMP_NUM_TCP_PCB_LISTEN\n"));
+#endif /* LWIP_NETCONN */
+#if LWIP_TCP
+  if (MEMP_NUM_TCP_SEG < TCP_SND_QUEUELEN)
+    LWIP_PLATFORM_DIAG(("lwip_sanity_check: WARNING: MEMP_NUM_TCP_SEG should be at least as big as TCP_SND_QUEUELEN\n"));
+  if (TCP_SND_BUF < 2 * TCP_MSS)
+    LWIP_PLATFORM_DIAG(("lwip_sanity_check: WARNING: TCP_SND_BUF must be at least as much as (2 * TCP_MSS) for things to work smoothly\n"));
+  if (TCP_SND_QUEUELEN < (2 * (TCP_SND_BUF/TCP_MSS)))
+    LWIP_PLATFORM_DIAG(("lwip_sanity_check: WARNING: TCP_SND_QUEUELEN must be at least as much as (2 * TCP_SND_BUF/TCP_MSS) for things to work\n"));
+  if (TCP_SNDLOWAT >= TCP_SND_BUF)
+    LWIP_PLATFORM_DIAG(("lwip_sanity_check: WARNING: TCP_SNDLOWAT must be less than TCP_SND_BUF.\n"));
+  if (TCP_SNDQUEUELOWAT >= TCP_SND_QUEUELEN)
+    LWIP_PLATFORM_DIAG(("lwip_sanity_check: WARNING: TCP_SNDQUEUELOWAT must be less than TCP_SND_QUEUELEN.\n"));
+  if (TCP_WND > (PBUF_POOL_SIZE*PBUF_POOL_BUFSIZE))
+    LWIP_PLATFORM_DIAG(("lwip_sanity_check: WARNING: TCP_WND is larger than space provided by PBUF_POOL_SIZE*PBUF_POOL_BUFSIZE\n"));
+  if (TCP_WND < TCP_MSS)
+    LWIP_PLATFORM_DIAG(("lwip_sanity_check: WARNING: TCP_WND is smaller than MSS\n"));
+#endif /* LWIP_TCP */
+#if LWIP_SOCKET
+  /* Check that the SO_* socket options and SOF_* lwIP-internal flags match */
+  if (SO_ACCEPTCONN != SOF_ACCEPTCONN)
+    LWIP_PLATFORM_DIAG(("lwip_sanity_check: WARNING: SO_ACCEPTCONN != SOF_ACCEPTCONN\n"));
+  if (SO_REUSEADDR != SOF_REUSEADDR)
+    LWIP_PLATFORM_DIAG(("lwip_sanity_check: WARNING: SO_REUSEADDR != SOF_REUSEADDR\n"));
+  if (SO_KEEPALIVE != SOF_KEEPALIVE)
+    LWIP_PLATFORM_DIAG(("lwip_sanity_check: WARNING: SO_KEEPALIVE != SOF_KEEPALIVE\n"));
+  if (SO_BROADCAST != SOF_BROADCAST)
+    LWIP_PLATFORM_DIAG(("lwip_sanity_check: WARNING: SO_BROADCAST != SOF_BROADCAST\n"));
+  if (SO_LINGER != SOF_LINGER)
+    LWIP_PLATFORM_DIAG(("lwip_sanity_check: WARNING: SO_LINGER != SOF_LINGER\n"));
+#endif /* LWIP_SOCKET */
+}
+#else  /* LWIP_DEBUG */
+#define lwip_sanity_check()
+#endif /* LWIP_DEBUG */
+
+/**
+ * Perform Sanity check of user-configurable values, and initialize all modules.
+ */
+void
+lwip_init(void)
+{
+  /* Sanity check user-configurable values */
+  lwip_sanity_check();
+
+  /* Modules initialization */
+  stats_init();
+#if !NO_SYS
+  sys_init();
+#endif /* !NO_SYS */
+  mem_init();
+  memp_init();
+  pbuf_init();
+  netif_init();
+#if LWIP_SOCKET
+  lwip_socket_init();
+#endif /* LWIP_SOCKET */
+  ip_init();
+#if LWIP_ARP
+  etharp_init();
+#endif /* LWIP_ARP */
+#if LWIP_RAW
+  raw_init();
+#endif /* LWIP_RAW */
+#if LWIP_UDP
+  udp_init();
+#endif /* LWIP_UDP */
+#if LWIP_TCP
+  tcp_init();
+#endif /* LWIP_TCP */
+#if LWIP_SNMP
+  snmp_init();
+#endif /* LWIP_SNMP */
+#if LWIP_AUTOIP
+  autoip_init();
+#endif /* LWIP_AUTOIP */
+#if LWIP_IGMP
+  igmp_init();
+#endif /* LWIP_IGMP */
+#if LWIP_DNS
+  dns_init();
+#endif /* LWIP_DNS */
+
+#if LWIP_TIMERS
+  sys_timeouts_init();
+#endif /* LWIP_TIMERS */
+}
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/core/ipv4/icmp.c	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,335 @@
+/**
+ * @file
+ * ICMP - Internet Control Message Protocol
+ *
+ */
+
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ *
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+
+/* Some ICMP messages should be passed to the transport protocols. This
+   is not implemented. */
+
+#include "lwip/opt.h"
+
+#if LWIP_ICMP /* don't build if not configured for use in lwipopts.h */
+
+#include "lwip/icmp.h"
+#include "lwip/inet_chksum.h"
+#include "lwip/ip.h"
+#include "lwip/def.h"
+#include "lwip/stats.h"
+#include "lwip/snmp.h"
+
+#include <string.h>
+
+/** Small optimization: set to 0 if incoming PBUF_POOL pbuf always can be
+ * used to modify and send a response packet (and to 1 if this is not the case,
+ * e.g. when link header is stripped of when receiving) */
+#ifndef LWIP_ICMP_ECHO_CHECK_INPUT_PBUF_LEN
+#define LWIP_ICMP_ECHO_CHECK_INPUT_PBUF_LEN 1
+#endif /* LWIP_ICMP_ECHO_CHECK_INPUT_PBUF_LEN */
+
+/* The amount of data from the original packet to return in a dest-unreachable */
+#define ICMP_DEST_UNREACH_DATASIZE 8
+
+static void icmp_send_response(struct pbuf *p, u8_t type, u8_t code);
+
+/**
+ * Processes ICMP input packets, called from ip_input().
+ *
+ * Currently only processes icmp echo requests and sends
+ * out the echo response.
+ *
+ * @param p the icmp echo request packet, p->payload pointing to the ip header
+ * @param inp the netif on which this packet was received
+ */
+void
+icmp_input(struct pbuf *p, struct netif *inp)
+{
+  u8_t type;
+#ifdef LWIP_DEBUG
+  u8_t code;
+#endif /* LWIP_DEBUG */
+  struct icmp_echo_hdr *iecho;
+  struct ip_hdr *iphdr;
+  s16_t hlen;
+
+  ICMP_STATS_INC(icmp.recv);
+  snmp_inc_icmpinmsgs();
+
+
+  iphdr = (struct ip_hdr *)p->payload;
+  hlen = IPH_HL(iphdr) * 4;
+  if (pbuf_header(p, -hlen) || (p->tot_len < sizeof(u16_t)*2)) {
+    LWIP_DEBUGF(ICMP_DEBUG, ("icmp_input: short ICMP (%"U16_F" bytes) received\n", p->tot_len));
+    goto lenerr;
+  }
+
+  type = *((u8_t *)p->payload);
+#ifdef LWIP_DEBUG
+  code = *(((u8_t *)p->payload)+1);
+#endif /* LWIP_DEBUG */
+  switch (type) {
+  case ICMP_ER:
+    /* This is OK, echo reply might have been parsed by a raw PCB
+       (as obviously, an echo request has been sent, too). */
+    break; 
+  case ICMP_ECHO:
+#if !LWIP_MULTICAST_PING || !LWIP_BROADCAST_PING
+    {
+      int accepted = 1;
+#if !LWIP_MULTICAST_PING
+      /* multicast destination address? */
+      if (ip_addr_ismulticast(&current_iphdr_dest)) {
+        accepted = 0;
+      }
+#endif /* LWIP_MULTICAST_PING */
+#if !LWIP_BROADCAST_PING
+      /* broadcast destination address? */
+      if (ip_addr_isbroadcast(&current_iphdr_dest, inp)) {
+        accepted = 0;
+      }
+#endif /* LWIP_BROADCAST_PING */
+      /* broadcast or multicast destination address not acceptd? */
+      if (!accepted) {
+        LWIP_DEBUGF(ICMP_DEBUG, ("icmp_input: Not echoing to multicast or broadcast pings\n"));
+        ICMP_STATS_INC(icmp.err);
+        pbuf_free(p);
+        return;
+      }
+    }
+#endif /* !LWIP_MULTICAST_PING || !LWIP_BROADCAST_PING */
+    LWIP_DEBUGF(ICMP_DEBUG, ("icmp_input: ping\n"));
+    if (p->tot_len < sizeof(struct icmp_echo_hdr)) {
+      LWIP_DEBUGF(ICMP_DEBUG, ("icmp_input: bad ICMP echo received\n"));
+      goto lenerr;
+    }
+    if (inet_chksum_pbuf(p) != 0) {
+      LWIP_DEBUGF(ICMP_DEBUG, ("icmp_input: checksum failed for received ICMP echo\n"));
+      pbuf_free(p);
+      ICMP_STATS_INC(icmp.chkerr);
+      snmp_inc_icmpinerrors();
+      return;
+    }
+#if LWIP_ICMP_ECHO_CHECK_INPUT_PBUF_LEN
+    if (pbuf_header(p, (PBUF_IP_HLEN + PBUF_LINK_HLEN))) {
+      /* p is not big enough to contain link headers
+       * allocate a new one and copy p into it
+       */
+      struct pbuf *r;
+      /* switch p->payload to ip header */
+      if (pbuf_header(p, hlen)) {
+        LWIP_ASSERT("icmp_input: moving p->payload to ip header failed\n", 0);
+        goto memerr;
+      }
+      /* allocate new packet buffer with space for link headers */
+      r = pbuf_alloc(PBUF_LINK, p->tot_len, PBUF_RAM);
+      if (r == NULL) {
+        LWIP_DEBUGF(ICMP_DEBUG, ("icmp_input: allocating new pbuf failed\n"));
+        goto memerr;
+      }
+      LWIP_ASSERT("check that first pbuf can hold struct the ICMP header",
+                  (r->len >= hlen + sizeof(struct icmp_echo_hdr)));
+      /* copy the whole packet including ip header */
+      if (pbuf_copy(r, p) != ERR_OK) {
+        LWIP_ASSERT("icmp_input: copying to new pbuf failed\n", 0);
+        goto memerr;
+      }
+      iphdr = (struct ip_hdr *)r->payload;
+      /* switch r->payload back to icmp header */
+      if (pbuf_header(r, -hlen)) {
+        LWIP_ASSERT("icmp_input: restoring original p->payload failed\n", 0);
+        goto memerr;
+      }
+      /* free the original p */
+      pbuf_free(p);
+      /* we now have an identical copy of p that has room for link headers */
+      p = r;
+    } else {
+      /* restore p->payload to point to icmp header */
+      if (pbuf_header(p, -(s16_t)(PBUF_IP_HLEN + PBUF_LINK_HLEN))) {
+        LWIP_ASSERT("icmp_input: restoring original p->payload failed\n", 0);
+        goto memerr;
+      }
+    }
+#endif /* LWIP_ICMP_ECHO_CHECK_INPUT_PBUF_LEN */
+    /* At this point, all checks are OK. */
+    /* We generate an answer by switching the dest and src ip addresses,
+     * setting the icmp type to ECHO_RESPONSE and updating the checksum. */
+    iecho = (struct icmp_echo_hdr *)p->payload;
+    ip_addr_copy(iphdr->src, *ip_current_dest_addr());
+    ip_addr_copy(iphdr->dest, *ip_current_src_addr());
+    ICMPH_TYPE_SET(iecho, ICMP_ER);
+    /* adjust the checksum */
+    if (iecho->chksum >= PP_HTONS(0xffff - (ICMP_ECHO << 8))) {
+      iecho->chksum += PP_HTONS(ICMP_ECHO << 8) + 1;
+    } else {
+      iecho->chksum += PP_HTONS(ICMP_ECHO << 8);
+    }
+
+    /* Set the correct TTL and recalculate the header checksum. */
+    IPH_TTL_SET(iphdr, ICMP_TTL);
+    IPH_CHKSUM_SET(iphdr, 0);
+#if CHECKSUM_GEN_IP
+    IPH_CHKSUM_SET(iphdr, inet_chksum(iphdr, IP_HLEN));
+#endif /* CHECKSUM_GEN_IP */
+
+    ICMP_STATS_INC(icmp.xmit);
+    /* increase number of messages attempted to send */
+    snmp_inc_icmpoutmsgs();
+    /* increase number of echo replies attempted to send */
+    snmp_inc_icmpoutechoreps();
+
+    if(pbuf_header(p, hlen)) {
+      LWIP_ASSERT("Can't move over header in packet", 0);
+    } else {
+      err_t ret;
+      /* send an ICMP packet, src addr is the dest addr of the curren packet */
+      ret = ip_output_if(p, ip_current_dest_addr(), IP_HDRINCL,
+                   ICMP_TTL, 0, IP_PROTO_ICMP, inp);
+      if (ret != ERR_OK) {
+        LWIP_DEBUGF(ICMP_DEBUG, ("icmp_input: ip_output_if returned an error: %c.\n", ret));
+      }
+    }
+    break;
+  default:
+    LWIP_DEBUGF(ICMP_DEBUG, ("icmp_input: ICMP type %"S16_F" code %"S16_F" not supported.\n", 
+                (s16_t)type, (s16_t)code));
+    ICMP_STATS_INC(icmp.proterr);
+    ICMP_STATS_INC(icmp.drop);
+  }
+  pbuf_free(p);
+  return;
+lenerr:
+  pbuf_free(p);
+  ICMP_STATS_INC(icmp.lenerr);
+  snmp_inc_icmpinerrors();
+  return;
+#if LWIP_ICMP_ECHO_CHECK_INPUT_PBUF_LEN
+memerr:
+  pbuf_free(p);
+  ICMP_STATS_INC(icmp.err);
+  snmp_inc_icmpinerrors();
+  return;
+#endif /* LWIP_ICMP_ECHO_CHECK_INPUT_PBUF_LEN */
+}
+
+/**
+ * Send an icmp 'destination unreachable' packet, called from ip_input() if
+ * the transport layer protocol is unknown and from udp_input() if the local
+ * port is not bound.
+ *
+ * @param p the input packet for which the 'unreachable' should be sent,
+ *          p->payload pointing to the IP header
+ * @param t type of the 'unreachable' packet
+ */
+void
+icmp_dest_unreach(struct pbuf *p, enum icmp_dur_type t)
+{
+  icmp_send_response(p, ICMP_DUR, t);
+}
+
+#if IP_FORWARD || IP_REASSEMBLY
+/**
+ * Send a 'time exceeded' packet, called from ip_forward() if TTL is 0.
+ *
+ * @param p the input packet for which the 'time exceeded' should be sent,
+ *          p->payload pointing to the IP header
+ * @param t type of the 'time exceeded' packet
+ */
+void
+icmp_time_exceeded(struct pbuf *p, enum icmp_te_type t)
+{
+  icmp_send_response(p, ICMP_TE, t);
+}
+
+#endif /* IP_FORWARD || IP_REASSEMBLY */
+
+/**
+ * Send an icmp packet in response to an incoming packet.
+ *
+ * @param p the input packet for which the 'unreachable' should be sent,
+ *          p->payload pointing to the IP header
+ * @param type Type of the ICMP header
+ * @param code Code of the ICMP header
+ */
+static void
+icmp_send_response(struct pbuf *p, u8_t type, u8_t code)
+{
+  struct pbuf *q;
+  struct ip_hdr *iphdr;
+  /* we can use the echo header here */
+  struct icmp_echo_hdr *icmphdr;
+  ip_addr_t iphdr_src;
+
+  /* ICMP header + IP header + 8 bytes of data */
+  q = pbuf_alloc(PBUF_IP, sizeof(struct icmp_echo_hdr) + IP_HLEN + ICMP_DEST_UNREACH_DATASIZE,
+                 PBUF_RAM);
+  if (q == NULL) {
+    LWIP_DEBUGF(ICMP_DEBUG, ("icmp_time_exceeded: failed to allocate pbuf for ICMP packet.\n"));
+    return;
+  }
+  LWIP_ASSERT("check that first pbuf can hold icmp message",
+             (q->len >= (sizeof(struct icmp_echo_hdr) + IP_HLEN + ICMP_DEST_UNREACH_DATASIZE)));
+
+  iphdr = (struct ip_hdr *)p->payload;
+  LWIP_DEBUGF(ICMP_DEBUG, ("icmp_time_exceeded from "));
+  ip_addr_debug_print(ICMP_DEBUG, &(iphdr->src));
+  LWIP_DEBUGF(ICMP_DEBUG, (" to "));
+  ip_addr_debug_print(ICMP_DEBUG, &(iphdr->dest));
+  LWIP_DEBUGF(ICMP_DEBUG, ("\n"));
+
+  icmphdr = (struct icmp_echo_hdr *)q->payload;
+  icmphdr->type = type;
+  icmphdr->code = code;
+  icmphdr->id = 0;
+  icmphdr->seqno = 0;
+
+  /* copy fields from original packet */
+  SMEMCPY((u8_t *)q->payload + sizeof(struct icmp_echo_hdr), (u8_t *)p->payload,
+          IP_HLEN + ICMP_DEST_UNREACH_DATASIZE);
+
+  /* calculate checksum */
+  icmphdr->chksum = 0;
+  icmphdr->chksum = inet_chksum(icmphdr, q->len);
+  ICMP_STATS_INC(icmp.xmit);
+  /* increase number of messages attempted to send */
+  snmp_inc_icmpoutmsgs();
+  /* increase number of destination unreachable messages attempted to send */
+  snmp_inc_icmpouttimeexcds();
+  ip_addr_copy(iphdr_src, iphdr->src);
+  ip_output(q, NULL, &iphdr_src, ICMP_TTL, 0, IP_PROTO_ICMP);
+  pbuf_free(q);
+}
+
+#endif /* LWIP_ICMP */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/core/ipv4/igmp.c	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,818 @@
+#pragma diag_remark 177
+/**
+ * @file
+ * IGMP - Internet Group Management Protocol
+ *
+ */
+
+/*
+ * Copyright (c) 2002 CITEL Technologies Ltd.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without 
+ * modification, are permitted provided that the following conditions 
+ * are met: 
+ * 1. Redistributions of source code must retain the above copyright 
+ *    notice, this list of conditions and the following disclaimer. 
+ * 2. Redistributions in binary form must reproduce the above copyright 
+ *    notice, this list of conditions and the following disclaimer in the 
+ *    documentation and/or other materials provided with the distribution. 
+ * 3. Neither the name of CITEL Technologies Ltd nor the names of its contributors 
+ *    may be used to endorse or promote products derived from this software 
+ *    without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY CITEL TECHNOLOGIES AND CONTRIBUTORS ``AS IS''
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
+ * ARE DISCLAIMED.  IN NO EVENT SHALL CITEL TECHNOLOGIES OR CONTRIBUTORS BE LIABLE 
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 
+ * SUCH DAMAGE. 
+ *
+ * This file is a contribution to the lwIP TCP/IP stack.
+ * The Swedish Institute of Computer Science and Adam Dunkels
+ * are specifically granted permission to redistribute this
+ * source code.
+*/
+
+/*-------------------------------------------------------------
+Note 1)
+Although the rfc requires V1 AND V2 capability
+we will only support v2 since now V1 is very old (August 1989)
+V1 can be added if required
+
+a debug print and statistic have been implemented to
+show this up.
+-------------------------------------------------------------
+-------------------------------------------------------------
+Note 2)
+A query for a specific group address (as opposed to ALLHOSTS)
+has now been implemented as I am unsure if it is required
+
+a debug print and statistic have been implemented to
+show this up.
+-------------------------------------------------------------
+-------------------------------------------------------------
+Note 3)
+The router alert rfc 2113 is implemented in outgoing packets
+but not checked rigorously incoming
+-------------------------------------------------------------
+Steve Reynolds
+------------------------------------------------------------*/
+
+/*-----------------------------------------------------------------------------
+ * RFC 988  - Host extensions for IP multicasting                         - V0
+ * RFC 1054 - Host extensions for IP multicasting                         -
+ * RFC 1112 - Host extensions for IP multicasting                         - V1
+ * RFC 2236 - Internet Group Management Protocol, Version 2               - V2  <- this code is based on this RFC (it's the "de facto" standard)
+ * RFC 3376 - Internet Group Management Protocol, Version 3               - V3
+ * RFC 4604 - Using Internet Group Management Protocol Version 3...       - V3+
+ * RFC 2113 - IP Router Alert Option                                      - 
+ *----------------------------------------------------------------------------*/
+
+/*-----------------------------------------------------------------------------
+ * Includes
+ *----------------------------------------------------------------------------*/
+
+#include "lwip/opt.h"
+
+#if LWIP_IGMP /* don't build if not configured for use in lwipopts.h */
+
+#include "lwip/igmp.h"
+#include "lwip/debug.h"
+#include "lwip/def.h"
+#include "lwip/mem.h"
+#include "lwip/ip.h"
+#include "lwip/inet_chksum.h"
+#include "lwip/netif.h"
+#include "lwip/icmp.h"
+#include "lwip/udp.h"
+#include "lwip/tcp.h"
+#include "lwip/stats.h"
+
+#include "string.h"
+
+/* 
+ * IGMP constants
+ */
+#define IGMP_TTL                       1
+#define IGMP_MINLEN                    8
+#define ROUTER_ALERT                   0x9404
+#define ROUTER_ALERTLEN                4
+
+/*
+ * IGMP message types, including version number.
+ */
+#define IGMP_MEMB_QUERY                0x11 /* Membership query         */
+#define IGMP_V1_MEMB_REPORT            0x12 /* Ver. 1 membership report */
+#define IGMP_V2_MEMB_REPORT            0x16 /* Ver. 2 membership report */
+#define IGMP_LEAVE_GROUP               0x17 /* Leave-group message      */
+
+/* Group  membership states */
+#define IGMP_GROUP_NON_MEMBER          0
+#define IGMP_GROUP_DELAYING_MEMBER     1
+#define IGMP_GROUP_IDLE_MEMBER         2
+
+/**
+ * IGMP packet format.
+ */
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/bpstruct.h"
+#endif
+PACK_STRUCT_BEGIN
+struct igmp_msg {
+ PACK_STRUCT_FIELD(u8_t           igmp_msgtype);
+ PACK_STRUCT_FIELD(u8_t           igmp_maxresp);
+ PACK_STRUCT_FIELD(u16_t          igmp_checksum);
+ PACK_STRUCT_FIELD(ip_addr_p_t    igmp_group_address);
+} PACK_STRUCT_STRUCT;
+PACK_STRUCT_END
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/epstruct.h"
+#endif
+
+
+static struct igmp_group *igmp_lookup_group(struct netif *ifp, ip_addr_t *addr);
+static err_t  igmp_remove_group(struct igmp_group *group);
+static void   igmp_timeout( struct igmp_group *group);
+static void   igmp_start_timer(struct igmp_group *group, u8_t max_time);
+static void   igmp_stop_timer(struct igmp_group *group);
+static void   igmp_delaying_member(struct igmp_group *group, u8_t maxresp);
+static err_t  igmp_ip_output_if(struct pbuf *p, ip_addr_t *src, ip_addr_t *dest, struct netif *netif);
+static void   igmp_send(struct igmp_group *group, u8_t type);
+
+
+static struct igmp_group* igmp_group_list;
+static ip_addr_t     allsystems;
+static ip_addr_t     allrouters;
+
+
+/**
+ * Initialize the IGMP module
+ */
+void
+igmp_init(void)
+{
+  LWIP_DEBUGF(IGMP_DEBUG, ("igmp_init: initializing\n"));
+
+  IP4_ADDR(&allsystems, 224, 0, 0, 1);
+  IP4_ADDR(&allrouters, 224, 0, 0, 2);
+}
+
+#ifdef LWIP_DEBUG
+/**
+ * Dump global IGMP groups list
+ */
+void
+igmp_dump_group_list()
+{ 
+  struct igmp_group *group = igmp_group_list;
+
+  while (group != NULL) {
+    LWIP_DEBUGF(IGMP_DEBUG, ("igmp_dump_group_list: [%"U32_F"] ", (u32_t)(group->group_state)));
+    ip_addr_debug_print(IGMP_DEBUG, &group->group_address);
+    LWIP_DEBUGF(IGMP_DEBUG, (" on if %p\n", group->netif));
+    group = group->next;
+  }
+  LWIP_DEBUGF(IGMP_DEBUG, ("\n"));
+}
+#else
+#define igmp_dump_group_list()
+#endif /* LWIP_DEBUG */
+
+/**
+ * Start IGMP processing on interface
+ *
+ * @param netif network interface on which start IGMP processing
+ */
+err_t
+igmp_start(struct netif *netif)
+{
+  struct igmp_group* group;
+
+  LWIP_DEBUGF(IGMP_DEBUG, ("igmp_start: starting IGMP processing on if %p\n", netif));
+
+  group = igmp_lookup_group(netif, &allsystems);
+
+  if (group != NULL) {
+    group->group_state = IGMP_GROUP_IDLE_MEMBER;
+    group->use++;
+
+    /* Allow the igmp messages at the MAC level */
+    if (netif->igmp_mac_filter != NULL) {
+      LWIP_DEBUGF(IGMP_DEBUG, ("igmp_start: igmp_mac_filter(ADD "));
+      ip_addr_debug_print(IGMP_DEBUG, &allsystems);
+      LWIP_DEBUGF(IGMP_DEBUG, (") on if %p\n", netif));
+      netif->igmp_mac_filter(netif, &allsystems, IGMP_ADD_MAC_FILTER);
+    }
+
+    return ERR_OK;
+  }
+
+  return ERR_MEM;
+}
+
+/**
+ * Stop IGMP processing on interface
+ *
+ * @param netif network interface on which stop IGMP processing
+ */
+err_t
+igmp_stop(struct netif *netif)
+{
+  struct igmp_group *group = igmp_group_list;
+  struct igmp_group *prev  = NULL;
+  struct igmp_group *next;
+
+  /* look for groups joined on this interface further down the list */
+  while (group != NULL) {
+    next = group->next;
+    /* is it a group joined on this interface? */
+    if (group->netif == netif) {
+      /* is it the first group of the list? */
+      if (group == igmp_group_list) {
+        igmp_group_list = next;
+      }
+      /* is there a "previous" group defined? */
+      if (prev != NULL) {
+        prev->next = next;
+      }
+      /* disable the group at the MAC level */
+      if (netif->igmp_mac_filter != NULL) {
+        LWIP_DEBUGF(IGMP_DEBUG, ("igmp_stop: igmp_mac_filter(DEL "));
+        ip_addr_debug_print(IGMP_DEBUG, &group->group_address);
+        LWIP_DEBUGF(IGMP_DEBUG, (") on if %p\n", netif));
+        netif->igmp_mac_filter(netif, &(group->group_address), IGMP_DEL_MAC_FILTER);
+      }
+      /* free group */
+      memp_free(MEMP_IGMP_GROUP, group);
+    } else {
+      /* change the "previous" */
+      prev = group;
+    }
+    /* move to "next" */
+    group = next;
+  }
+  return ERR_OK;
+}
+
+/**
+ * Report IGMP memberships for this interface
+ *
+ * @param netif network interface on which report IGMP memberships
+ */
+void
+igmp_report_groups(struct netif *netif)
+{
+  struct igmp_group *group = igmp_group_list;
+
+  LWIP_DEBUGF(IGMP_DEBUG, ("igmp_report_groups: sending IGMP reports on if %p\n", netif));
+
+  while (group != NULL) {
+    if (group->netif == netif) {
+      igmp_delaying_member(group, IGMP_JOIN_DELAYING_MEMBER_TMR);
+    }
+    group = group->next;
+  }
+}
+
+/**
+ * Search for a group in the global igmp_group_list
+ *
+ * @param ifp the network interface for which to look
+ * @param addr the group ip address to search for
+ * @return a struct igmp_group* if the group has been found,
+ *         NULL if the group wasn't found.
+ */
+struct igmp_group *
+igmp_lookfor_group(struct netif *ifp, ip_addr_t *addr)
+{
+  struct igmp_group *group = igmp_group_list;
+
+  while (group != NULL) {
+    if ((group->netif == ifp) && (ip_addr_cmp(&(group->group_address), addr))) {
+      return group;
+    }
+    group = group->next;
+  }
+
+  /* to be clearer, we return NULL here instead of
+   * 'group' (which is also NULL at this point).
+   */
+  return NULL;
+}
+
+/**
+ * Search for a specific igmp group and create a new one if not found-
+ *
+ * @param ifp the network interface for which to look
+ * @param addr the group ip address to search
+ * @return a struct igmp_group*,
+ *         NULL on memory error.
+ */
+struct igmp_group *
+igmp_lookup_group(struct netif *ifp, ip_addr_t *addr)
+{
+  struct igmp_group *group = igmp_group_list;
+  
+  /* Search if the group already exists */
+  group = igmp_lookfor_group(ifp, addr);
+  if (group != NULL) {
+    /* Group already exists. */
+    return group;
+  }
+
+  /* Group doesn't exist yet, create a new one */
+  group = (struct igmp_group *)memp_malloc(MEMP_IGMP_GROUP);
+  if (group != NULL) {
+    group->netif              = ifp;
+    ip_addr_set(&(group->group_address), addr);
+    group->timer              = 0; /* Not running */
+    group->group_state        = IGMP_GROUP_NON_MEMBER;
+    group->last_reporter_flag = 0;
+    group->use                = 0;
+    group->next               = igmp_group_list;
+    
+    igmp_group_list = group;
+  }
+
+  LWIP_DEBUGF(IGMP_DEBUG, ("igmp_lookup_group: %sallocated a new group with address ", (group?"":"impossible to ")));
+  ip_addr_debug_print(IGMP_DEBUG, addr);
+  LWIP_DEBUGF(IGMP_DEBUG, (" on if %p\n", ifp));
+
+  return group;
+}
+
+/**
+ * Remove a group in the global igmp_group_list
+ *
+ * @param group the group to remove from the global igmp_group_list
+ * @return ERR_OK if group was removed from the list, an err_t otherwise
+ */
+static err_t
+igmp_remove_group(struct igmp_group *group)
+{
+  err_t err = ERR_OK;
+
+  /* Is it the first group? */
+  if (igmp_group_list == group) {
+    igmp_group_list = group->next;
+  } else {
+    /* look for group further down the list */
+    struct igmp_group *tmpGroup;
+    for (tmpGroup = igmp_group_list; tmpGroup != NULL; tmpGroup = tmpGroup->next) {
+      if (tmpGroup->next == group) {
+        tmpGroup->next = group->next;
+        break;
+      }
+    }
+    /* Group not found in the global igmp_group_list */
+    if (tmpGroup == NULL)
+      err = ERR_ARG;
+  }
+  /* free group */
+  memp_free(MEMP_IGMP_GROUP, group);
+
+  return err;
+}
+
+/**
+ * Called from ip_input() if a new IGMP packet is received.
+ *
+ * @param p received igmp packet, p->payload pointing to the ip header
+ * @param inp network interface on which the packet was received
+ * @param dest destination ip address of the igmp packet
+ */
+void
+igmp_input(struct pbuf *p, struct netif *inp, ip_addr_t *dest)
+{
+  struct ip_hdr *    iphdr;
+  struct igmp_msg*   igmp;
+  struct igmp_group* group;
+  struct igmp_group* groupref;
+
+  IGMP_STATS_INC(igmp.recv);
+
+  /* Note that the length CAN be greater than 8 but only 8 are used - All are included in the checksum */    
+  iphdr = (struct ip_hdr *)p->payload;
+  if (pbuf_header(p, -(s16_t)(IPH_HL(iphdr) * 4)) || (p->len < IGMP_MINLEN)) {
+    pbuf_free(p);
+    IGMP_STATS_INC(igmp.lenerr);
+    LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: length error\n"));
+    return;
+  }
+
+  LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: message from "));
+  ip_addr_debug_print(IGMP_DEBUG, &(iphdr->src));
+  LWIP_DEBUGF(IGMP_DEBUG, (" to address "));
+  ip_addr_debug_print(IGMP_DEBUG, &(iphdr->dest));
+  LWIP_DEBUGF(IGMP_DEBUG, (" on if %p\n", inp));
+
+  /* Now calculate and check the checksum */
+  igmp = (struct igmp_msg *)p->payload;
+  if (inet_chksum(igmp, p->len)) {
+    pbuf_free(p);
+    IGMP_STATS_INC(igmp.chkerr);
+    LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: checksum error\n"));
+    return;
+  }
+
+  /* Packet is ok so find an existing group */
+  group = igmp_lookfor_group(inp, dest); /* use the destination IP address of incoming packet */
+  
+  /* If group can be found or create... */
+  if (!group) {
+    pbuf_free(p);
+    IGMP_STATS_INC(igmp.drop);
+    LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: IGMP frame not for us\n"));
+    return;
+  }
+
+  /* NOW ACT ON THE INCOMING MESSAGE TYPE... */
+  switch (igmp->igmp_msgtype) {
+   case IGMP_MEMB_QUERY: {
+     /* IGMP_MEMB_QUERY to the "all systems" address ? */
+     if ((ip_addr_cmp(dest, &allsystems)) && ip_addr_isany(&igmp->igmp_group_address)) {
+       /* THIS IS THE GENERAL QUERY */
+       LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: General IGMP_MEMB_QUERY on \"ALL SYSTEMS\" address (224.0.0.1) [igmp_maxresp=%i]\n", (int)(igmp->igmp_maxresp)));
+
+       if (igmp->igmp_maxresp == 0) {
+         IGMP_STATS_INC(igmp.rx_v1);
+         LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: got an all hosts query with time== 0 - this is V1 and not implemented - treat as v2\n"));
+         igmp->igmp_maxresp = IGMP_V1_DELAYING_MEMBER_TMR;
+       } else {
+         IGMP_STATS_INC(igmp.rx_general);
+       }
+
+       groupref = igmp_group_list;
+       while (groupref) {
+         /* Do not send messages on the all systems group address! */
+         if ((groupref->netif == inp) && (!(ip_addr_cmp(&(groupref->group_address), &allsystems)))) {
+           igmp_delaying_member(groupref, igmp->igmp_maxresp);
+         }
+         groupref = groupref->next;
+       }
+     } else {
+       /* IGMP_MEMB_QUERY to a specific group ? */
+       if (!ip_addr_isany(&igmp->igmp_group_address)) {
+         LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: IGMP_MEMB_QUERY to a specific group "));
+         ip_addr_debug_print(IGMP_DEBUG, &igmp->igmp_group_address);
+         if (ip_addr_cmp(dest, &allsystems)) {
+           ip_addr_t groupaddr;
+           LWIP_DEBUGF(IGMP_DEBUG, (" using \"ALL SYSTEMS\" address (224.0.0.1) [igmp_maxresp=%i]\n", (int)(igmp->igmp_maxresp)));
+           /* we first need to re-look for the group since we used dest last time */
+           ip_addr_copy(groupaddr, igmp->igmp_group_address);
+           group = igmp_lookfor_group(inp, &groupaddr);
+         } else {
+           LWIP_DEBUGF(IGMP_DEBUG, (" with the group address as destination [igmp_maxresp=%i]\n", (int)(igmp->igmp_maxresp)));
+         }
+
+         if (group != NULL) {
+           IGMP_STATS_INC(igmp.rx_group);
+           igmp_delaying_member(group, igmp->igmp_maxresp);
+         } else {
+           IGMP_STATS_INC(igmp.drop);
+         }
+       } else {
+         IGMP_STATS_INC(igmp.proterr);
+       }
+     }
+     break;
+   }
+   case IGMP_V2_MEMB_REPORT: {
+     LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: IGMP_V2_MEMB_REPORT\n"));
+     IGMP_STATS_INC(igmp.rx_report);
+     if (group->group_state == IGMP_GROUP_DELAYING_MEMBER) {
+       /* This is on a specific group we have already looked up */
+       group->timer = 0; /* stopped */
+       group->group_state = IGMP_GROUP_IDLE_MEMBER;
+       group->last_reporter_flag = 0;
+     }
+     break;
+   }
+   default: {
+     LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: unexpected msg %d in state %d on group %p on if %p\n",
+       igmp->igmp_msgtype, group->group_state, &group, group->netif));
+     IGMP_STATS_INC(igmp.proterr);
+     break;
+   }
+  }
+
+  pbuf_free(p);
+  return;
+}
+
+/**
+ * Join a group on one network interface.
+ *
+ * @param ifaddr ip address of the network interface which should join a new group
+ * @param groupaddr the ip address of the group which to join
+ * @return ERR_OK if group was joined on the netif(s), an err_t otherwise
+ */
+err_t
+igmp_joingroup(ip_addr_t *ifaddr, ip_addr_t *groupaddr)
+{
+  err_t              err = ERR_VAL; /* no matching interface */
+  struct igmp_group *group;
+  struct netif      *netif;
+
+  /* make sure it is multicast address */
+  LWIP_ERROR("igmp_joingroup: attempt to join non-multicast address", ip_addr_ismulticast(groupaddr), return ERR_VAL;);
+  LWIP_ERROR("igmp_joingroup: attempt to join allsystems address", (!ip_addr_cmp(groupaddr, &allsystems)), return ERR_VAL;);
+
+  /* loop through netif's */
+  netif = netif_list;
+  while (netif != NULL) {
+    /* Should we join this interface ? */
+    if ((netif->flags & NETIF_FLAG_IGMP) && ((ip_addr_isany(ifaddr) || ip_addr_cmp(&(netif->ip_addr), ifaddr)))) {
+      /* find group or create a new one if not found */
+      group = igmp_lookup_group(netif, groupaddr);
+
+      if (group != NULL) {
+        /* This should create a new group, check the state to make sure */
+        if (group->group_state != IGMP_GROUP_NON_MEMBER) {
+          LWIP_DEBUGF(IGMP_DEBUG, ("igmp_joingroup: join to group not in state IGMP_GROUP_NON_MEMBER\n"));
+        } else {
+          /* OK - it was new group */
+          LWIP_DEBUGF(IGMP_DEBUG, ("igmp_joingroup: join to new group: "));
+          ip_addr_debug_print(IGMP_DEBUG, groupaddr);
+          LWIP_DEBUGF(IGMP_DEBUG, ("\n"));
+
+          /* If first use of the group, allow the group at the MAC level */
+          if ((group->use==0) && (netif->igmp_mac_filter != NULL)) {
+            LWIP_DEBUGF(IGMP_DEBUG, ("igmp_joingroup: igmp_mac_filter(ADD "));
+            ip_addr_debug_print(IGMP_DEBUG, groupaddr);
+            LWIP_DEBUGF(IGMP_DEBUG, (") on if %p\n", netif));
+            netif->igmp_mac_filter(netif, groupaddr, IGMP_ADD_MAC_FILTER);
+          }
+
+          IGMP_STATS_INC(igmp.tx_join);
+          igmp_send(group, IGMP_V2_MEMB_REPORT);
+
+          igmp_start_timer(group, IGMP_JOIN_DELAYING_MEMBER_TMR);
+
+          /* Need to work out where this timer comes from */
+          group->group_state = IGMP_GROUP_DELAYING_MEMBER;
+        }
+        /* Increment group use */
+        group->use++;
+        /* Join on this interface */
+        err = ERR_OK;
+      } else {
+        /* Return an error even if some network interfaces are joined */
+        /** @todo undo any other netif already joined */
+        LWIP_DEBUGF(IGMP_DEBUG, ("igmp_joingroup: Not enought memory to join to group\n"));
+        return ERR_MEM;
+      }
+    }
+    /* proceed to next network interface */
+    netif = netif->next;
+  }
+
+  return err;
+}
+
+/**
+ * Leave a group on one network interface.
+ *
+ * @param ifaddr ip address of the network interface which should leave a group
+ * @param groupaddr the ip address of the group which to leave
+ * @return ERR_OK if group was left on the netif(s), an err_t otherwise
+ */
+err_t
+igmp_leavegroup(ip_addr_t *ifaddr, ip_addr_t *groupaddr)
+{
+  err_t              err = ERR_VAL; /* no matching interface */
+  struct igmp_group *group;
+  struct netif      *netif;
+
+  /* make sure it is multicast address */
+  LWIP_ERROR("igmp_leavegroup: attempt to leave non-multicast address", ip_addr_ismulticast(groupaddr), return ERR_VAL;);
+  LWIP_ERROR("igmp_leavegroup: attempt to leave allsystems address", (!ip_addr_cmp(groupaddr, &allsystems)), return ERR_VAL;);
+
+  /* loop through netif's */
+  netif = netif_list;
+  while (netif != NULL) {
+    /* Should we leave this interface ? */
+    if ((netif->flags & NETIF_FLAG_IGMP) && ((ip_addr_isany(ifaddr) || ip_addr_cmp(&(netif->ip_addr), ifaddr)))) {
+      /* find group */
+      group = igmp_lookfor_group(netif, groupaddr);
+
+      if (group != NULL) {
+        /* Only send a leave if the flag is set according to the state diagram */
+        LWIP_DEBUGF(IGMP_DEBUG, ("igmp_leavegroup: Leaving group: "));
+        ip_addr_debug_print(IGMP_DEBUG, groupaddr);
+        LWIP_DEBUGF(IGMP_DEBUG, ("\n"));
+
+        /* If there is no other use of the group */
+        if (group->use <= 1) {
+          /* If we are the last reporter for this group */
+          if (group->last_reporter_flag) {
+            LWIP_DEBUGF(IGMP_DEBUG, ("igmp_leavegroup: sending leaving group\n"));
+            IGMP_STATS_INC(igmp.tx_leave);
+            igmp_send(group, IGMP_LEAVE_GROUP);
+          }
+          
+          /* Disable the group at the MAC level */
+          if (netif->igmp_mac_filter != NULL) {
+            LWIP_DEBUGF(IGMP_DEBUG, ("igmp_leavegroup: igmp_mac_filter(DEL "));
+            ip_addr_debug_print(IGMP_DEBUG, groupaddr);
+            LWIP_DEBUGF(IGMP_DEBUG, (") on if %p\n", netif));
+            netif->igmp_mac_filter(netif, groupaddr, IGMP_DEL_MAC_FILTER);
+          }
+          
+          LWIP_DEBUGF(IGMP_DEBUG, ("igmp_leavegroup: remove group: "));
+          ip_addr_debug_print(IGMP_DEBUG, groupaddr);
+          LWIP_DEBUGF(IGMP_DEBUG, ("\n"));          
+          
+          /* Free the group */
+          igmp_remove_group(group);
+        } else {
+          /* Decrement group use */
+          group->use--;
+        }
+        /* Leave on this interface */
+        err = ERR_OK;
+      } else {
+        /* It's not a fatal error on "leavegroup" */
+        LWIP_DEBUGF(IGMP_DEBUG, ("igmp_leavegroup: not member of group\n"));
+      }
+    }
+    /* proceed to next network interface */
+    netif = netif->next;
+  }
+
+  return err;
+}
+
+/**
+ * The igmp timer function (both for NO_SYS=1 and =0)
+ * Should be called every IGMP_TMR_INTERVAL milliseconds (100 ms is default).
+ */
+void
+igmp_tmr(void)
+{
+  struct igmp_group *group = igmp_group_list;
+
+  while (group != NULL) {
+    if (group->timer > 0) {
+      group->timer--;
+      if (group->timer == 0) {
+        igmp_timeout(group);
+      }
+    }
+    group = group->next;
+  }
+}
+
+/**
+ * Called if a timeout for one group is reached.
+ * Sends a report for this group.
+ *
+ * @param group an igmp_group for which a timeout is reached
+ */
+static void
+igmp_timeout(struct igmp_group *group)
+{
+  /* If the state is IGMP_GROUP_DELAYING_MEMBER then we send a report for this group */
+  if (group->group_state == IGMP_GROUP_DELAYING_MEMBER) {
+    LWIP_DEBUGF(IGMP_DEBUG, ("igmp_timeout: report membership for group with address "));
+    ip_addr_debug_print(IGMP_DEBUG, &(group->group_address));
+    LWIP_DEBUGF(IGMP_DEBUG, (" on if %p\n", group->netif));
+
+    IGMP_STATS_INC(igmp.tx_report);
+    igmp_send(group, IGMP_V2_MEMB_REPORT);
+  }
+}
+
+/**
+ * Start a timer for an igmp group
+ *
+ * @param group the igmp_group for which to start a timer
+ * @param max_time the time in multiples of IGMP_TMR_INTERVAL (decrease with
+ *        every call to igmp_tmr())
+ */
+static void
+igmp_start_timer(struct igmp_group *group, u8_t max_time)
+{
+  /* ensure the input value is > 0 */
+  if (max_time == 0) {
+    max_time = 1;
+  }
+  /* ensure the random value is > 0 */
+  group->timer = (LWIP_RAND() % (max_time - 1)) + 1;
+}
+
+/**
+ * Stop a timer for an igmp_group
+ *
+ * @param group the igmp_group for which to stop the timer
+ */
+static void
+igmp_stop_timer(struct igmp_group *group)
+{
+  group->timer = 0;
+}
+
+/**
+ * Delaying membership report for a group if necessary
+ *
+ * @param group the igmp_group for which "delaying" membership report
+ * @param maxresp query delay
+ */
+static void
+igmp_delaying_member(struct igmp_group *group, u8_t maxresp)
+{
+  if ((group->group_state == IGMP_GROUP_IDLE_MEMBER) ||
+     ((group->group_state == IGMP_GROUP_DELAYING_MEMBER) &&
+      ((group->timer == 0) || (maxresp < group->timer)))) {
+    igmp_start_timer(group, maxresp);
+    group->group_state = IGMP_GROUP_DELAYING_MEMBER;
+  }
+}
+
+
+/**
+ * Sends an IP packet on a network interface. This function constructs the IP header
+ * and calculates the IP header checksum. If the source IP address is NULL,
+ * the IP address of the outgoing network interface is filled in as source address.
+ *
+ * @param p the packet to send (p->payload points to the data, e.g. next
+            protocol header; if dest == IP_HDRINCL, p already includes an IP
+            header and p->payload points to that IP header)
+ * @param src the source IP address to send from (if src == IP_ADDR_ANY, the
+ *         IP  address of the netif used to send is used as source address)
+ * @param dest the destination IP address to send the packet to
+ * @param ttl the TTL value to be set in the IP header
+ * @param proto the PROTOCOL to be set in the IP header
+ * @param netif the netif on which to send this packet
+ * @return ERR_OK if the packet was sent OK
+ *         ERR_BUF if p doesn't have enough space for IP/LINK headers
+ *         returns errors returned by netif->output
+ */
+static err_t
+igmp_ip_output_if(struct pbuf *p, ip_addr_t *src, ip_addr_t *dest, struct netif *netif)
+{
+  /* This is the "router alert" option */
+  u16_t ra[2];
+  ra[0] = PP_HTONS(ROUTER_ALERT);
+  ra[1] = 0x0000; /* Router shall examine packet */
+  IGMP_STATS_INC(igmp.xmit);
+  return ip_output_if_opt(p, src, dest, IGMP_TTL, 0, IP_PROTO_IGMP, netif, ra, ROUTER_ALERTLEN);
+}
+
+/**
+ * Send an igmp packet to a specific group.
+ *
+ * @param group the group to which to send the packet
+ * @param type the type of igmp packet to send
+ */
+static void
+igmp_send(struct igmp_group *group, u8_t type)
+{
+  struct pbuf*     p    = NULL;
+  struct igmp_msg* igmp = NULL;
+  ip_addr_t   src  = *IP_ADDR_ANY;
+  ip_addr_t*  dest = NULL;
+
+  /* IP header + "router alert" option + IGMP header */
+  p = pbuf_alloc(PBUF_TRANSPORT, IGMP_MINLEN, PBUF_RAM);
+  
+  if (p) {
+    igmp = (struct igmp_msg *)p->payload;
+    LWIP_ASSERT("igmp_send: check that first pbuf can hold struct igmp_msg",
+               (p->len >= sizeof(struct igmp_msg)));
+    ip_addr_copy(src, group->netif->ip_addr);
+     
+    if (type == IGMP_V2_MEMB_REPORT) {
+      dest = &(group->group_address);
+      ip_addr_copy(igmp->igmp_group_address, group->group_address);
+      group->last_reporter_flag = 1; /* Remember we were the last to report */
+    } else {
+      if (type == IGMP_LEAVE_GROUP) {
+        dest = &allrouters;
+        ip_addr_copy(igmp->igmp_group_address, group->group_address);
+      }
+    }
+
+    if ((type == IGMP_V2_MEMB_REPORT) || (type == IGMP_LEAVE_GROUP)) {
+      igmp->igmp_msgtype  = type;
+      igmp->igmp_maxresp  = 0;
+      igmp->igmp_checksum = 0;
+      igmp->igmp_checksum = inet_chksum(igmp, IGMP_MINLEN);
+
+      igmp_ip_output_if(p, &src, dest, group->netif);
+    }
+
+    pbuf_free(p);
+  } else {
+    LWIP_DEBUGF(IGMP_DEBUG, ("igmp_send: not enough memory for igmp_send\n"));
+    IGMP_STATS_INC(igmp.memerr);
+  }
+}
+
+#endif /* LWIP_IGMP */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/core/ipv4/inet.c	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,42 @@
+/**
+ * @file
+ * Functions common to all TCP/IPv4 modules, such as the byte order functions.
+ *
+ */
+
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ *
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+
+#include "lwip/opt.h"
+
+#include "lwip/inet.h"
+
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/core/ipv4/inet_chksum.c	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,450 @@
+/**
+ * @file
+ * Incluse internet checksum functions.
+ *
+ */
+
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ *
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+
+#include "lwip/opt.h"
+
+#include "lwip/inet_chksum.h"
+#include "lwip/def.h"
+
+#include <stddef.h>
+#include <string.h>
+
+/* These are some reference implementations of the checksum algorithm, with the
+ * aim of being simple, correct and fully portable. Checksumming is the
+ * first thing you would want to optimize for your platform. If you create
+ * your own version, link it in and in your cc.h put:
+ * 
+ * #define LWIP_CHKSUM <your_checksum_routine> 
+ *
+ * Or you can select from the implementations below by defining
+ * LWIP_CHKSUM_ALGORITHM to 1, 2 or 3.
+ */
+
+#ifndef LWIP_CHKSUM
+# define LWIP_CHKSUM lwip_standard_chksum
+# ifndef LWIP_CHKSUM_ALGORITHM
+#  define LWIP_CHKSUM_ALGORITHM 2
+# endif
+#endif
+/* If none set: */
+#ifndef LWIP_CHKSUM_ALGORITHM
+# define LWIP_CHKSUM_ALGORITHM 0
+#endif
+
+#if (LWIP_CHKSUM_ALGORITHM == 1) /* Version #1 */
+/**
+ * lwip checksum
+ *
+ * @param dataptr points to start of data to be summed at any boundary
+ * @param len length of data to be summed
+ * @return host order (!) lwip checksum (non-inverted Internet sum) 
+ *
+ * @note accumulator size limits summable length to 64k
+ * @note host endianess is irrelevant (p3 RFC1071)
+ */
+static u16_t
+lwip_standard_chksum(void *dataptr, u16_t len)
+{
+  u32_t acc;
+  u16_t src;
+  u8_t *octetptr;
+
+  acc = 0;
+  /* dataptr may be at odd or even addresses */
+  octetptr = (u8_t*)dataptr;
+  while (len > 1) {
+    /* declare first octet as most significant
+       thus assume network order, ignoring host order */
+    src = (*octetptr) << 8;
+    octetptr++;
+    /* declare second octet as least significant */
+    src |= (*octetptr);
+    octetptr++;
+    acc += src;
+    len -= 2;
+  }
+  if (len > 0) {
+    /* accumulate remaining octet */
+    src = (*octetptr) << 8;
+    acc += src;
+  }
+  /* add deferred carry bits */
+  acc = (acc >> 16) + (acc & 0x0000ffffUL);
+  if ((acc & 0xffff0000UL) != 0) {
+    acc = (acc >> 16) + (acc & 0x0000ffffUL);
+  }
+  /* This maybe a little confusing: reorder sum using htons()
+     instead of ntohs() since it has a little less call overhead.
+     The caller must invert bits for Internet sum ! */
+  return htons((u16_t)acc);
+}
+#endif
+
+#if (LWIP_CHKSUM_ALGORITHM == 2) /* Alternative version #2 */
+/*
+ * Curt McDowell
+ * Broadcom Corp.
+ * csm@broadcom.com
+ *
+ * IP checksum two bytes at a time with support for
+ * unaligned buffer.
+ * Works for len up to and including 0x20000.
+ * by Curt McDowell, Broadcom Corp. 12/08/2005
+ *
+ * @param dataptr points to start of data to be summed at any boundary
+ * @param len length of data to be summed
+ * @return host order (!) lwip checksum (non-inverted Internet sum) 
+ */
+
+static u16_t
+lwip_standard_chksum(void *dataptr, int len)
+{
+  u8_t *pb = (u8_t *)dataptr;
+  u16_t *ps, t = 0;
+  u32_t sum = 0;
+  int odd = ((mem_ptr_t)pb & 1);
+
+  /* Get aligned to u16_t */
+  if (odd && len > 0) {
+    ((u8_t *)&t)[1] = *pb++;
+    len--;
+  }
+
+  /* Add the bulk of the data */
+  ps = (u16_t *)(void *)pb;
+  while (len > 1) {
+    sum += *ps++;
+    len -= 2;
+  }
+
+  /* Consume left-over byte, if any */
+  if (len > 0) {
+    ((u8_t *)&t)[0] = *(u8_t *)ps;
+  }
+
+  /* Add end bytes */
+  sum += t;
+
+  /* Fold 32-bit sum to 16 bits
+     calling this twice is propably faster than if statements... */
+  sum = FOLD_U32T(sum);
+  sum = FOLD_U32T(sum);
+
+  /* Swap if alignment was odd */
+  if (odd) {
+    sum = SWAP_BYTES_IN_WORD(sum);
+  }
+
+  return (u16_t)sum;
+}
+#endif
+
+#if (LWIP_CHKSUM_ALGORITHM == 3) /* Alternative version #3 */
+/**
+ * An optimized checksum routine. Basically, it uses loop-unrolling on
+ * the checksum loop, treating the head and tail bytes specially, whereas
+ * the inner loop acts on 8 bytes at a time. 
+ *
+ * @arg start of buffer to be checksummed. May be an odd byte address.
+ * @len number of bytes in the buffer to be checksummed.
+ * @return host order (!) lwip checksum (non-inverted Internet sum) 
+ * 
+ * by Curt McDowell, Broadcom Corp. December 8th, 2005
+ */
+
+static u16_t
+lwip_standard_chksum(void *dataptr, int len)
+{
+  u8_t *pb = (u8_t *)dataptr;
+  u16_t *ps, t = 0;
+  u32_t *pl;
+  u32_t sum = 0, tmp;
+  /* starts at odd byte address? */
+  int odd = ((mem_ptr_t)pb & 1);
+
+  if (odd && len > 0) {
+    ((u8_t *)&t)[1] = *pb++;
+    len--;
+  }
+
+  ps = (u16_t *)pb;
+
+  if (((mem_ptr_t)ps & 3) && len > 1) {
+    sum += *ps++;
+    len -= 2;
+  }
+
+  pl = (u32_t *)ps;
+
+  while (len > 7)  {
+    tmp = sum + *pl++;          /* ping */
+    if (tmp < sum) {
+      tmp++;                    /* add back carry */
+    }
+
+    sum = tmp + *pl++;          /* pong */
+    if (sum < tmp) {
+      sum++;                    /* add back carry */
+    }
+
+    len -= 8;
+  }
+
+  /* make room in upper bits */
+  sum = FOLD_U32T(sum);
+
+  ps = (u16_t *)pl;
+
+  /* 16-bit aligned word remaining? */
+  while (len > 1) {
+    sum += *ps++;
+    len -= 2;
+  }
+
+  /* dangling tail byte remaining? */
+  if (len > 0) {                /* include odd byte */
+    ((u8_t *)&t)[0] = *(u8_t *)ps;
+  }
+
+  sum += t;                     /* add end bytes */
+
+  /* Fold 32-bit sum to 16 bits
+     calling this twice is propably faster than if statements... */
+  sum = FOLD_U32T(sum);
+  sum = FOLD_U32T(sum);
+
+  if (odd) {
+    sum = SWAP_BYTES_IN_WORD(sum);
+  }
+
+  return (u16_t)sum;
+}
+#endif
+
+/* inet_chksum_pseudo:
+ *
+ * Calculates the pseudo Internet checksum used by TCP and UDP for a pbuf chain.
+ * IP addresses are expected to be in network byte order.
+ *
+ * @param p chain of pbufs over that a checksum should be calculated (ip data part)
+ * @param src source ip address (used for checksum of pseudo header)
+ * @param dst destination ip address (used for checksum of pseudo header)
+ * @param proto ip protocol (used for checksum of pseudo header)
+ * @param proto_len length of the ip data part (used for checksum of pseudo header)
+ * @return checksum (as u16_t) to be saved directly in the protocol header
+ */
+u16_t
+inet_chksum_pseudo(struct pbuf *p,
+       ip_addr_t *src, ip_addr_t *dest,
+       u8_t proto, u16_t proto_len)
+{
+  u32_t acc;
+  u32_t addr;
+  struct pbuf *q;
+  u8_t swapped;
+
+  acc = 0;
+  swapped = 0;
+  /* iterate through all pbuf in chain */
+  for(q = p; q != NULL; q = q->next) {
+    LWIP_DEBUGF(INET_DEBUG, ("inet_chksum_pseudo(): checksumming pbuf %p (has next %p) \n",
+      (void *)q, (void *)q->next));
+    acc += LWIP_CHKSUM(q->payload, q->len);
+    /*LWIP_DEBUGF(INET_DEBUG, ("inet_chksum_pseudo(): unwrapped lwip_chksum()=%"X32_F" \n", acc));*/
+    /* just executing this next line is probably faster that the if statement needed
+       to check whether we really need to execute it, and does no harm */
+    acc = FOLD_U32T(acc);
+    if (q->len % 2 != 0) {
+      swapped = 1 - swapped;
+      acc = SWAP_BYTES_IN_WORD(acc);
+    }
+    /*LWIP_DEBUGF(INET_DEBUG, ("inet_chksum_pseudo(): wrapped lwip_chksum()=%"X32_F" \n", acc));*/
+  }
+
+  if (swapped) {
+    acc = SWAP_BYTES_IN_WORD(acc);
+  }
+  addr = ip4_addr_get_u32(src);
+  acc += (addr & 0xffffUL);
+  acc += ((addr >> 16) & 0xffffUL);
+  addr = ip4_addr_get_u32(dest);
+  acc += (addr & 0xffffUL);
+  acc += ((addr >> 16) & 0xffffUL);
+  acc += (u32_t)htons((u16_t)proto);
+  acc += (u32_t)htons(proto_len);
+
+  /* Fold 32-bit sum to 16 bits
+     calling this twice is propably faster than if statements... */
+  acc = FOLD_U32T(acc);
+  acc = FOLD_U32T(acc);
+  LWIP_DEBUGF(INET_DEBUG, ("inet_chksum_pseudo(): pbuf chain lwip_chksum()=%"X32_F"\n", acc));
+  return (u16_t)~(acc & 0xffffUL);
+}
+
+/* inet_chksum_pseudo:
+ *
+ * Calculates the pseudo Internet checksum used by TCP and UDP for a pbuf chain.
+ * IP addresses are expected to be in network byte order.
+ *
+ * @param p chain of pbufs over that a checksum should be calculated (ip data part)
+ * @param src source ip address (used for checksum of pseudo header)
+ * @param dst destination ip address (used for checksum of pseudo header)
+ * @param proto ip protocol (used for checksum of pseudo header)
+ * @param proto_len length of the ip data part (used for checksum of pseudo header)
+ * @return checksum (as u16_t) to be saved directly in the protocol header
+ */
+u16_t
+inet_chksum_pseudo_partial(struct pbuf *p,
+       ip_addr_t *src, ip_addr_t *dest,
+       u8_t proto, u16_t proto_len, u16_t chksum_len)
+{
+  u32_t acc;
+  u32_t addr;
+  struct pbuf *q;
+  u8_t swapped;
+  u16_t chklen;
+
+  acc = 0;
+  swapped = 0;
+  /* iterate through all pbuf in chain */
+  for(q = p; (q != NULL) && (chksum_len > 0); q = q->next) {
+    LWIP_DEBUGF(INET_DEBUG, ("inet_chksum_pseudo(): checksumming pbuf %p (has next %p) \n",
+      (void *)q, (void *)q->next));
+    chklen = q->len;
+    if (chklen > chksum_len) {
+      chklen = chksum_len;
+    }
+    acc += LWIP_CHKSUM(q->payload, chklen);
+    chksum_len -= chklen;
+    LWIP_ASSERT("delete me", chksum_len < 0x7fff);
+    /*LWIP_DEBUGF(INET_DEBUG, ("inet_chksum_pseudo(): unwrapped lwip_chksum()=%"X32_F" \n", acc));*/
+    /* fold the upper bit down */
+    acc = FOLD_U32T(acc);
+    if (q->len % 2 != 0) {
+      swapped = 1 - swapped;
+      acc = SWAP_BYTES_IN_WORD(acc);
+    }
+    /*LWIP_DEBUGF(INET_DEBUG, ("inet_chksum_pseudo(): wrapped lwip_chksum()=%"X32_F" \n", acc));*/
+  }
+
+  if (swapped) {
+    acc = SWAP_BYTES_IN_WORD(acc);
+  }
+  addr = ip4_addr_get_u32(src);
+  acc += (addr & 0xffffUL);
+  acc += ((addr >> 16) & 0xffffUL);
+  addr = ip4_addr_get_u32(dest);
+  acc += (addr & 0xffffUL);
+  acc += ((addr >> 16) & 0xffffUL);
+  acc += (u32_t)htons((u16_t)proto);
+  acc += (u32_t)htons(proto_len);
+
+  /* Fold 32-bit sum to 16 bits
+     calling this twice is propably faster than if statements... */
+  acc = FOLD_U32T(acc);
+  acc = FOLD_U32T(acc);
+  LWIP_DEBUGF(INET_DEBUG, ("inet_chksum_pseudo(): pbuf chain lwip_chksum()=%"X32_F"\n", acc));
+  return (u16_t)~(acc & 0xffffUL);
+}
+
+/* inet_chksum:
+ *
+ * Calculates the Internet checksum over a portion of memory. Used primarily for IP
+ * and ICMP.
+ *
+ * @param dataptr start of the buffer to calculate the checksum (no alignment needed)
+ * @param len length of the buffer to calculate the checksum
+ * @return checksum (as u16_t) to be saved directly in the protocol header
+ */
+
+u16_t
+inet_chksum(void *dataptr, u16_t len)
+{
+  return ~LWIP_CHKSUM(dataptr, len);
+}
+
+/**
+ * Calculate a checksum over a chain of pbufs (without pseudo-header, much like
+ * inet_chksum only pbufs are used).
+ *
+ * @param p pbuf chain over that the checksum should be calculated
+ * @return checksum (as u16_t) to be saved directly in the protocol header
+ */
+u16_t
+inet_chksum_pbuf(struct pbuf *p)
+{
+  u32_t acc;
+  struct pbuf *q;
+  u8_t swapped;
+
+  acc = 0;
+  swapped = 0;
+  for(q = p; q != NULL; q = q->next) {
+    acc += LWIP_CHKSUM(q->payload, q->len);
+    acc = FOLD_U32T(acc);
+    if (q->len % 2 != 0) {
+      swapped = 1 - swapped;
+      acc = SWAP_BYTES_IN_WORD(acc);
+    }
+  }
+
+  if (swapped) {
+    acc = SWAP_BYTES_IN_WORD(acc);
+  }
+  return (u16_t)~(acc & 0xffffUL);
+}
+
+/* These are some implementations for LWIP_CHKSUM_COPY, which copies data
+ * like MEMCPY but generates a checksum at the same time. Since this is a
+ * performance-sensitive function, you might want to create your own version
+ * in assembly targeted at your hardware by defining it in lwipopts.h:
+ *   #define LWIP_CHKSUM_COPY(dst, src, len) your_chksum_copy(dst, src, len)
+ */
+
+#if (LWIP_CHKSUM_COPY_ALGORITHM == 1) /* Version #1 */
+/** Safe but slow: first call MEMCPY, then call LWIP_CHKSUM.
+ * For architectures with big caches, data might still be in cache when
+ * generating the checksum after copying.
+ */
+u16_t
+lwip_chksum_copy(void *dst, const void *src, u16_t len)
+{
+  MEMCPY(dst, src, len);
+  return LWIP_CHKSUM(dst, len);
+}
+#endif /* (LWIP_CHKSUM_COPY_ALGORITHM == 1) */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/core/ipv4/ip.c	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,857 @@
+/**
+ * @file
+ * This is the IPv4 layer implementation for incoming and outgoing IP traffic.
+ * 
+ * @see ip_frag.c
+ *
+ */
+
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ *
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+
+#include "lwip/opt.h"
+#include "lwip/ip.h"
+#include "lwip/def.h"
+#include "lwip/mem.h"
+#include "lwip/ip_frag.h"
+#include "lwip/inet_chksum.h"
+#include "lwip/netif.h"
+#include "lwip/icmp.h"
+#include "lwip/igmp.h"
+#include "lwip/raw.h"
+#include "lwip/udp.h"
+#include "lwip/tcp_impl.h"
+#include "lwip/snmp.h"
+#include "lwip/dhcp.h"
+#include "lwip/autoip.h"
+#include "lwip/stats.h"
+#include "arch/perf.h"
+
+#include <string.h>
+
+/** Set this to 0 in the rare case of wanting to call an extra function to
+ * generate the IP checksum (in contrast to calculating it on-the-fly). */
+#ifndef LWIP_INLINE_IP_CHKSUM
+#define LWIP_INLINE_IP_CHKSUM   1
+#endif
+#if LWIP_INLINE_IP_CHKSUM && CHECKSUM_GEN_IP
+#define CHECKSUM_GEN_IP_INLINE  1
+#else
+#define CHECKSUM_GEN_IP_INLINE  0
+#endif
+
+#if LWIP_DHCP || defined(LWIP_IP_ACCEPT_UDP_PORT)
+#define IP_ACCEPT_LINK_LAYER_ADDRESSING 1
+
+/** Some defines for DHCP to let link-layer-addressed packets through while the
+ * netif is down.
+ * To use this in your own application/protocol, define LWIP_IP_ACCEPT_UDP_PORT
+ * to return 1 if the port is accepted and 0 if the port is not accepted.
+ */
+#if LWIP_DHCP && defined(LWIP_IP_ACCEPT_UDP_PORT)
+/* accept DHCP client port and custom port */
+#define IP_ACCEPT_LINK_LAYER_ADDRESSED_PORT(port) (((port) == PP_NTOHS(DHCP_CLIENT_PORT)) \
+         || (LWIP_IP_ACCEPT_UDP_PORT(port)))
+#elif defined(LWIP_IP_ACCEPT_UDP_PORT) /* LWIP_DHCP && defined(LWIP_IP_ACCEPT_UDP_PORT) */
+/* accept custom port only */
+#define IP_ACCEPT_LINK_LAYER_ADDRESSED_PORT(port) (LWIP_IP_ACCEPT_UDP_PORT(dst_port))
+#else /* LWIP_DHCP && defined(LWIP_IP_ACCEPT_UDP_PORT) */
+/* accept DHCP client port only */
+#define IP_ACCEPT_LINK_LAYER_ADDRESSED_PORT(port) ((port) == PP_NTOHS(DHCP_CLIENT_PORT))
+#endif /* LWIP_DHCP && defined(LWIP_IP_ACCEPT_UDP_PORT) */
+
+#else /* LWIP_DHCP */
+#define IP_ACCEPT_LINK_LAYER_ADDRESSING 0
+#endif /* LWIP_DHCP */
+
+/**
+ * The interface that provided the packet for the current callback
+ * invocation.
+ */
+struct netif *current_netif;
+
+/**
+ * Header of the input packet currently being processed.
+ */
+const struct ip_hdr *current_header;
+/** Source IP address of current_header */
+ip_addr_t current_iphdr_src;
+/** Destination IP address of current_header */
+ip_addr_t current_iphdr_dest;
+
+/** The IP header ID of the next outgoing IP packet */
+static u16_t ip_id;
+
+/**
+ * Finds the appropriate network interface for a given IP address. It
+ * searches the list of network interfaces linearly. A match is found
+ * if the masked IP address of the network interface equals the masked
+ * IP address given to the function.
+ *
+ * @param dest the destination IP address for which to find the route
+ * @return the netif on which to send to reach dest
+ */
+struct netif *
+ip_route(ip_addr_t *dest)
+{
+  struct netif *netif;
+
+  /* iterate through netifs */
+  for(netif = netif_list; netif != NULL; netif = netif->next) {
+    /* network mask matches? */
+    if (netif_is_up(netif)) {
+      if (ip_addr_netcmp(dest, &(netif->ip_addr), &(netif->netmask))) {
+        /* return netif on which to forward IP packet */
+        return netif;
+      }
+    }
+  }
+  if ((netif_default == NULL) || (!netif_is_up(netif_default))) {
+    LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("ip_route: No route to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
+      ip4_addr1_16(dest), ip4_addr2_16(dest), ip4_addr3_16(dest), ip4_addr4_16(dest)));
+    IP_STATS_INC(ip.rterr);
+    snmp_inc_ipoutnoroutes();
+    return NULL;
+  }
+  /* no matching netif found, use default netif */
+  return netif_default;
+}
+
+#if IP_FORWARD
+/**
+ * Forwards an IP packet. It finds an appropriate route for the
+ * packet, decrements the TTL value of the packet, adjusts the
+ * checksum and outputs the packet on the appropriate interface.
+ *
+ * @param p the packet to forward (p->payload points to IP header)
+ * @param iphdr the IP header of the input packet
+ * @param inp the netif on which this packet was received
+ */
+static void
+ip_forward(struct pbuf *p, struct ip_hdr *iphdr, struct netif *inp)
+{
+  struct netif *netif;
+
+  PERF_START;
+
+  /* RFC3927 2.7: do not forward link-local addresses */
+  if (ip_addr_islinklocal(&current_iphdr_dest)) {
+    LWIP_DEBUGF(IP_DEBUG, ("ip_forward: not forwarding LLA %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
+      ip4_addr1_16(&current_iphdr_dest), ip4_addr2_16(&current_iphdr_dest),
+      ip4_addr3_16(&current_iphdr_dest), ip4_addr4_16(&current_iphdr_dest)));
+    goto return_noroute;
+  }
+
+  /* Find network interface where to forward this IP packet to. */
+  netif = ip_route(&current_iphdr_dest);
+  if (netif == NULL) {
+    LWIP_DEBUGF(IP_DEBUG, ("ip_forward: no forwarding route for %"U16_F".%"U16_F".%"U16_F".%"U16_F" found\n",
+      ip4_addr1_16(&current_iphdr_dest), ip4_addr2_16(&current_iphdr_dest),
+      ip4_addr3_16(&current_iphdr_dest), ip4_addr4_16(&current_iphdr_dest)));
+    goto return_noroute;
+  }
+  /* Do not forward packets onto the same network interface on which
+   * they arrived. */
+  if (netif == inp) {
+    LWIP_DEBUGF(IP_DEBUG, ("ip_forward: not bouncing packets back on incoming interface.\n"));
+    goto return_noroute;
+  }
+
+  /* decrement TTL */
+  IPH_TTL_SET(iphdr, IPH_TTL(iphdr) - 1);
+  /* send ICMP if TTL == 0 */
+  if (IPH_TTL(iphdr) == 0) {
+    snmp_inc_ipinhdrerrors();
+#if LWIP_ICMP
+    /* Don't send ICMP messages in response to ICMP messages */
+    if (IPH_PROTO(iphdr) != IP_PROTO_ICMP) {
+      icmp_time_exceeded(p, ICMP_TE_TTL);
+    }
+#endif /* LWIP_ICMP */
+    return;
+  }
+
+  /* Incrementally update the IP checksum. */
+  if (IPH_CHKSUM(iphdr) >= PP_HTONS(0xffff - 0x100)) {
+    IPH_CHKSUM_SET(iphdr, IPH_CHKSUM(iphdr) + PP_HTONS(0x100) + 1);
+  } else {
+    IPH_CHKSUM_SET(iphdr, IPH_CHKSUM(iphdr) + PP_HTONS(0x100));
+  }
+
+  LWIP_DEBUGF(IP_DEBUG, ("ip_forward: forwarding packet to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
+    ip4_addr1_16(&current_iphdr_dest), ip4_addr2_16(&current_iphdr_dest),
+    ip4_addr3_16(&current_iphdr_dest), ip4_addr4_16(&current_iphdr_dest)));
+
+  IP_STATS_INC(ip.fw);
+  IP_STATS_INC(ip.xmit);
+  snmp_inc_ipforwdatagrams();
+
+  PERF_STOP("ip_forward");
+  /* transmit pbuf on chosen interface */
+  netif->output(netif, p, &current_iphdr_dest);
+  return;
+return_noroute:
+  snmp_inc_ipoutnoroutes();
+}
+#endif /* IP_FORWARD */
+
+/**
+ * This function is called by the network interface device driver when
+ * an IP packet is received. The function does the basic checks of the
+ * IP header such as packet size being at least larger than the header
+ * size etc. If the packet was not destined for us, the packet is
+ * forwarded (using ip_forward). The IP checksum is always checked.
+ *
+ * Finally, the packet is sent to the upper layer protocol input function.
+ * 
+ * @param p the received IP packet (p->payload points to IP header)
+ * @param inp the netif on which this packet was received
+ * @return ERR_OK if the packet was processed (could return ERR_* if it wasn't
+ *         processed, but currently always returns ERR_OK)
+ */
+err_t
+ip_input(struct pbuf *p, struct netif *inp)
+{
+  struct ip_hdr *iphdr;
+  struct netif *netif;
+  u16_t iphdr_hlen;
+  u16_t iphdr_len;
+#if IP_ACCEPT_LINK_LAYER_ADDRESSING
+  int check_ip_src=1;
+#endif /* IP_ACCEPT_LINK_LAYER_ADDRESSING */
+
+  IP_STATS_INC(ip.recv);
+  snmp_inc_ipinreceives();
+
+  /* identify the IP header */
+  iphdr = (struct ip_hdr *)p->payload;
+  if (IPH_V(iphdr) != 4) {
+    LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_WARNING, ("IP packet dropped due to bad version number %"U16_F"\n", IPH_V(iphdr)));
+    ip_debug_print(p);
+    pbuf_free(p);
+    IP_STATS_INC(ip.err);
+    IP_STATS_INC(ip.drop);
+    snmp_inc_ipinhdrerrors();
+    return ERR_OK;
+  }
+
+  /* obtain IP header length in number of 32-bit words */
+  iphdr_hlen = IPH_HL(iphdr);
+  /* calculate IP header length in bytes */
+  iphdr_hlen *= 4;
+  /* obtain ip length in bytes */
+  iphdr_len = ntohs(IPH_LEN(iphdr));
+
+  /* header length exceeds first pbuf length, or ip length exceeds total pbuf length? */
+  if ((iphdr_hlen > p->len) || (iphdr_len > p->tot_len)) {
+    if (iphdr_hlen > p->len) {
+      LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
+        ("IP header (len %"U16_F") does not fit in first pbuf (len %"U16_F"), IP packet dropped.\n",
+        iphdr_hlen, p->len));
+    }
+    if (iphdr_len > p->tot_len) {
+      LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
+        ("IP (len %"U16_F") is longer than pbuf (len %"U16_F"), IP packet dropped.\n",
+        iphdr_len, p->tot_len));
+    }
+    /* free (drop) packet pbufs */
+    pbuf_free(p);
+    IP_STATS_INC(ip.lenerr);
+    IP_STATS_INC(ip.drop);
+    snmp_inc_ipindiscards();
+    return ERR_OK;
+  }
+
+  /* verify checksum */
+#if CHECKSUM_CHECK_IP
+  if (inet_chksum(iphdr, iphdr_hlen) != 0) {
+
+    LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
+      ("Checksum (0x%"X16_F") failed, IP packet dropped.\n", inet_chksum(iphdr, iphdr_hlen)));
+    ip_debug_print(p);
+    pbuf_free(p);
+    IP_STATS_INC(ip.chkerr);
+    IP_STATS_INC(ip.drop);
+    snmp_inc_ipinhdrerrors();
+    return ERR_OK;
+  }
+#endif
+
+  /* Trim pbuf. This should have been done at the netif layer,
+   * but we'll do it anyway just to be sure that its done. */
+  pbuf_realloc(p, iphdr_len);
+
+  /* copy IP addresses to aligned ip_addr_t */
+  ip_addr_copy(current_iphdr_dest, iphdr->dest);
+  ip_addr_copy(current_iphdr_src, iphdr->src);
+
+  /* match packet against an interface, i.e. is this packet for us? */
+#if LWIP_IGMP
+  if (ip_addr_ismulticast(&current_iphdr_dest)) {
+    if ((inp->flags & NETIF_FLAG_IGMP) && (igmp_lookfor_group(inp, &current_iphdr_dest))) {
+      netif = inp;
+    } else {
+      netif = NULL;
+    }
+  } else
+#endif /* LWIP_IGMP */
+  {
+    /* start trying with inp. if that's not acceptable, start walking the
+       list of configured netifs.
+       'first' is used as a boolean to mark whether we started walking the list */
+    int first = 1;
+    netif = inp;
+    do {
+      LWIP_DEBUGF(IP_DEBUG, ("ip_input: iphdr->dest 0x%"X32_F" netif->ip_addr 0x%"X32_F" (0x%"X32_F", 0x%"X32_F", 0x%"X32_F")\n",
+          ip4_addr_get_u32(&iphdr->dest), ip4_addr_get_u32(&netif->ip_addr),
+          ip4_addr_get_u32(&iphdr->dest) & ip4_addr_get_u32(&netif->netmask),
+          ip4_addr_get_u32(&netif->ip_addr) & ip4_addr_get_u32(&netif->netmask),
+          ip4_addr_get_u32(&iphdr->dest) & ~ip4_addr_get_u32(&netif->netmask)));
+
+      /* interface is up and configured? */
+      if ((netif_is_up(netif)) && (!ip_addr_isany(&(netif->ip_addr)))) {
+        /* unicast to this interface address? */
+        if (ip_addr_cmp(&current_iphdr_dest, &(netif->ip_addr)) ||
+            /* or broadcast on this interface network address? */
+            ip_addr_isbroadcast(&current_iphdr_dest, netif)) {
+          LWIP_DEBUGF(IP_DEBUG, ("ip_input: packet accepted on interface %c%c\n",
+              netif->name[0], netif->name[1]));
+          /* break out of for loop */
+          break;
+        }
+#if LWIP_AUTOIP
+        /* connections to link-local addresses must persist after changing
+           the netif's address (RFC3927 ch. 1.9) */
+        if ((netif->autoip != NULL) &&
+            ip_addr_cmp(&current_iphdr_dest, &(netif->autoip->llipaddr))) {
+          LWIP_DEBUGF(IP_DEBUG, ("ip_input: LLA packet accepted on interface %c%c\n",
+              netif->name[0], netif->name[1]));
+          /* break out of for loop */
+          break;
+        }
+#endif /* LWIP_AUTOIP */
+      }
+      if (first) {
+        first = 0;
+        netif = netif_list;
+      } else {
+        netif = netif->next;
+      }
+      if (netif == inp) {
+        netif = netif->next;
+      }
+    } while(netif != NULL);
+  }
+
+#if IP_ACCEPT_LINK_LAYER_ADDRESSING
+  /* Pass DHCP messages regardless of destination address. DHCP traffic is addressed
+   * using link layer addressing (such as Ethernet MAC) so we must not filter on IP.
+   * According to RFC 1542 section 3.1.1, referred by RFC 2131).
+   *
+   * If you want to accept private broadcast communication while a netif is down,
+   * define LWIP_IP_ACCEPT_UDP_PORT(dst_port), e.g.:
+   *
+   * #define LWIP_IP_ACCEPT_UDP_PORT(dst_port) ((dst_port) == PP_NTOHS(12345))
+   */
+  if (netif == NULL) {
+    /* remote port is DHCP server? */
+    if (IPH_PROTO(iphdr) == IP_PROTO_UDP) {
+      struct udp_hdr *udphdr = (struct udp_hdr *)((u8_t *)iphdr + iphdr_hlen);
+      LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_TRACE, ("ip_input: UDP packet to DHCP client port %"U16_F"\n",
+        ntohs(udphdr->dest)));
+      if (IP_ACCEPT_LINK_LAYER_ADDRESSED_PORT(udphdr->dest)) {
+        LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_TRACE, ("ip_input: DHCP packet accepted.\n"));
+        netif = inp;
+        check_ip_src = 0;
+      }
+    }
+  }
+#endif /* IP_ACCEPT_LINK_LAYER_ADDRESSING */
+
+  /* broadcast or multicast packet source address? Compliant with RFC 1122: 3.2.1.3 */
+#if IP_ACCEPT_LINK_LAYER_ADDRESSING
+  /* DHCP servers need 0.0.0.0 to be allowed as source address (RFC 1.1.2.2: 3.2.1.3/a) */
+  if (check_ip_src && !ip_addr_isany(&current_iphdr_src))
+#endif /* IP_ACCEPT_LINK_LAYER_ADDRESSING */
+  {  if ((ip_addr_isbroadcast(&current_iphdr_src, inp)) ||
+         (ip_addr_ismulticast(&current_iphdr_src))) {
+      /* packet source is not valid */
+      LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_WARNING, ("ip_input: packet source is not valid.\n"));
+      /* free (drop) packet pbufs */
+      pbuf_free(p);
+      IP_STATS_INC(ip.drop);
+      snmp_inc_ipinaddrerrors();
+      snmp_inc_ipindiscards();
+      return ERR_OK;
+    }
+  }
+
+  /* packet not for us? */
+  if (netif == NULL) {
+    /* packet not for us, route or discard */
+    LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_TRACE, ("ip_input: packet not for us.\n"));
+#if IP_FORWARD
+    /* non-broadcast packet? */
+    if (!ip_addr_isbroadcast(&current_iphdr_dest, inp)) {
+      /* try to forward IP packet on (other) interfaces */
+      ip_forward(p, iphdr, inp);
+    } else
+#endif /* IP_FORWARD */
+    {
+      snmp_inc_ipinaddrerrors();
+      snmp_inc_ipindiscards();
+    }
+    pbuf_free(p);
+    return ERR_OK;
+  }
+  /* packet consists of multiple fragments? */
+  if ((IPH_OFFSET(iphdr) & PP_HTONS(IP_OFFMASK | IP_MF)) != 0) {
+#if IP_REASSEMBLY /* packet fragment reassembly code present? */
+    LWIP_DEBUGF(IP_DEBUG, ("IP packet is a fragment (id=0x%04"X16_F" tot_len=%"U16_F" len=%"U16_F" MF=%"U16_F" offset=%"U16_F"), calling ip_reass()\n",
+      ntohs(IPH_ID(iphdr)), p->tot_len, ntohs(IPH_LEN(iphdr)), !!(IPH_OFFSET(iphdr) & PP_HTONS(IP_MF)), (ntohs(IPH_OFFSET(iphdr)) & IP_OFFMASK)*8));
+    /* reassemble the packet*/
+    p = ip_reass(p);
+    /* packet not fully reassembled yet? */
+    if (p == NULL) {
+      return ERR_OK;
+    }
+    iphdr = (struct ip_hdr *)p->payload;
+#else /* IP_REASSEMBLY == 0, no packet fragment reassembly code present */
+    pbuf_free(p);
+    LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("IP packet dropped since it was fragmented (0x%"X16_F") (while IP_REASSEMBLY == 0).\n",
+      ntohs(IPH_OFFSET(iphdr))));
+    IP_STATS_INC(ip.opterr);
+    IP_STATS_INC(ip.drop);
+    /* unsupported protocol feature */
+    snmp_inc_ipinunknownprotos();
+    return ERR_OK;
+#endif /* IP_REASSEMBLY */
+  }
+
+#if IP_OPTIONS_ALLOWED == 0 /* no support for IP options in the IP header? */
+
+#if LWIP_IGMP
+  /* there is an extra "router alert" option in IGMP messages which we allow for but do not police */
+  if((iphdr_hlen > IP_HLEN) &&  (IPH_PROTO(iphdr) != IP_PROTO_IGMP)) {
+#else
+  if (iphdr_hlen > IP_HLEN) {
+#endif /* LWIP_IGMP */
+    LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("IP packet dropped since there were IP options (while IP_OPTIONS_ALLOWED == 0).\n"));
+    pbuf_free(p);
+    IP_STATS_INC(ip.opterr);
+    IP_STATS_INC(ip.drop);
+    /* unsupported protocol feature */
+    snmp_inc_ipinunknownprotos();
+    return ERR_OK;
+  }
+#endif /* IP_OPTIONS_ALLOWED == 0 */
+
+  /* send to upper layers */
+  LWIP_DEBUGF(IP_DEBUG, ("ip_input: \n"));
+  ip_debug_print(p);
+  LWIP_DEBUGF(IP_DEBUG, ("ip_input: p->len %"U16_F" p->tot_len %"U16_F"\n", p->len, p->tot_len));
+
+  current_netif = inp;
+  current_header = iphdr;
+
+#if LWIP_RAW
+  /* raw input did not eat the packet? */
+  if (raw_input(p, inp) == 0)
+#endif /* LWIP_RAW */
+  {
+
+    switch (IPH_PROTO(iphdr)) {
+#if LWIP_UDP
+    case IP_PROTO_UDP:
+#if LWIP_UDPLITE
+    case IP_PROTO_UDPLITE:
+#endif /* LWIP_UDPLITE */
+      snmp_inc_ipindelivers();
+      udp_input(p, inp);
+      break;
+#endif /* LWIP_UDP */
+#if LWIP_TCP
+    case IP_PROTO_TCP:
+      snmp_inc_ipindelivers();
+      tcp_input(p, inp);
+      break;
+#endif /* LWIP_TCP */
+#if LWIP_ICMP
+    case IP_PROTO_ICMP:
+      snmp_inc_ipindelivers();
+      icmp_input(p, inp);
+      break;
+#endif /* LWIP_ICMP */
+#if LWIP_IGMP
+    case IP_PROTO_IGMP:
+      igmp_input(p, inp, &current_iphdr_dest);
+      break;
+#endif /* LWIP_IGMP */
+    default:
+#if LWIP_ICMP
+      /* send ICMP destination protocol unreachable unless is was a broadcast */
+      if (!ip_addr_isbroadcast(&current_iphdr_dest, inp) &&
+          !ip_addr_ismulticast(&current_iphdr_dest)) {
+        p->payload = iphdr;
+        icmp_dest_unreach(p, ICMP_DUR_PROTO);
+      }
+#endif /* LWIP_ICMP */
+      pbuf_free(p);
+
+      LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("Unsupported transport protocol %"U16_F"\n", IPH_PROTO(iphdr)));
+
+      IP_STATS_INC(ip.proterr);
+      IP_STATS_INC(ip.drop);
+      snmp_inc_ipinunknownprotos();
+    }
+  }
+
+  current_netif = NULL;
+  current_header = NULL;
+  ip_addr_set_any(&current_iphdr_src);
+  ip_addr_set_any(&current_iphdr_dest);
+
+  return ERR_OK;
+}
+
+/**
+ * Sends an IP packet on a network interface. This function constructs
+ * the IP header and calculates the IP header checksum. If the source
+ * IP address is NULL, the IP address of the outgoing network
+ * interface is filled in as source address.
+ * If the destination IP address is IP_HDRINCL, p is assumed to already
+ * include an IP header and p->payload points to it instead of the data.
+ *
+ * @param p the packet to send (p->payload points to the data, e.g. next
+            protocol header; if dest == IP_HDRINCL, p already includes an IP
+            header and p->payload points to that IP header)
+ * @param src the source IP address to send from (if src == IP_ADDR_ANY, the
+ *         IP  address of the netif used to send is used as source address)
+ * @param dest the destination IP address to send the packet to
+ * @param ttl the TTL value to be set in the IP header
+ * @param tos the TOS value to be set in the IP header
+ * @param proto the PROTOCOL to be set in the IP header
+ * @param netif the netif on which to send this packet
+ * @return ERR_OK if the packet was sent OK
+ *         ERR_BUF if p doesn't have enough space for IP/LINK headers
+ *         returns errors returned by netif->output
+ *
+ * @note ip_id: RFC791 "some host may be able to simply use
+ *  unique identifiers independent of destination"
+ */
+err_t
+ip_output_if(struct pbuf *p, ip_addr_t *src, ip_addr_t *dest,
+             u8_t ttl, u8_t tos,
+             u8_t proto, struct netif *netif)
+{
+#if IP_OPTIONS_SEND
+  return ip_output_if_opt(p, src, dest, ttl, tos, proto, netif, NULL, 0);
+}
+
+/**
+ * Same as ip_output_if() but with the possibility to include IP options:
+ *
+ * @ param ip_options pointer to the IP options, copied into the IP header
+ * @ param optlen length of ip_options
+ */
+err_t ip_output_if_opt(struct pbuf *p, ip_addr_t *src, ip_addr_t *dest,
+       u8_t ttl, u8_t tos, u8_t proto, struct netif *netif, void *ip_options,
+       u16_t optlen)
+{
+#endif /* IP_OPTIONS_SEND */
+  struct ip_hdr *iphdr;
+  ip_addr_t dest_addr;
+#if CHECKSUM_GEN_IP_INLINE
+  u32_t chk_sum = 0;
+#endif /* CHECKSUM_GEN_IP_INLINE */
+
+  /* pbufs passed to IP must have a ref-count of 1 as their payload pointer
+     gets altered as the packet is passed down the stack */
+  LWIP_ASSERT("p->ref == 1", p->ref == 1);
+
+  snmp_inc_ipoutrequests();
+
+  /* Should the IP header be generated or is it already included in p? */
+  if (dest != IP_HDRINCL) {
+    u16_t ip_hlen = IP_HLEN;
+#if IP_OPTIONS_SEND
+    u16_t optlen_aligned = 0;
+    if (optlen != 0) {
+#if CHECKSUM_GEN_IP_INLINE
+      int i;
+#endif /* CHECKSUM_GEN_IP_INLINE */
+      /* round up to a multiple of 4 */
+      optlen_aligned = ((optlen + 3) & ~3);
+      ip_hlen += optlen_aligned;
+      /* First write in the IP options */
+      if (pbuf_header(p, optlen_aligned)) {
+        LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("ip_output_if_opt: not enough room for IP options in pbuf\n"));
+        IP_STATS_INC(ip.err);
+        snmp_inc_ipoutdiscards();
+        return ERR_BUF;
+      }
+      MEMCPY(p->payload, ip_options, optlen);
+      if (optlen < optlen_aligned) {
+        /* zero the remaining bytes */
+        memset(((char*)p->payload) + optlen, 0, optlen_aligned - optlen);
+      }
+#if CHECKSUM_GEN_IP_INLINE
+      for (i = 0; i < optlen_aligned; i += sizeof(u16_t)) {
+        chk_sum += ((u16_t*)p->payload)[i];
+      }
+#endif /* CHECKSUM_GEN_IP_INLINE */
+    }
+#endif /* IP_OPTIONS_SEND */
+    /* generate IP header */
+    if (pbuf_header(p, IP_HLEN)) {
+      LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("ip_output: not enough room for IP header in pbuf\n"));
+
+      IP_STATS_INC(ip.err);
+      snmp_inc_ipoutdiscards();
+      return ERR_BUF;
+    }
+
+    iphdr = (struct ip_hdr *)p->payload;
+    LWIP_ASSERT("check that first pbuf can hold struct ip_hdr",
+               (p->len >= sizeof(struct ip_hdr)));
+
+    IPH_TTL_SET(iphdr, ttl);
+    IPH_PROTO_SET(iphdr, proto);
+#if CHECKSUM_GEN_IP_INLINE
+    chk_sum += LWIP_MAKE_U16(proto, ttl);
+#endif /* CHECKSUM_GEN_IP_INLINE */
+
+    /* dest cannot be NULL here */
+    ip_addr_copy(iphdr->dest, *dest);
+#if CHECKSUM_GEN_IP_INLINE
+    chk_sum += ip4_addr_get_u32(&iphdr->dest) & 0xFFFF;
+    chk_sum += ip4_addr_get_u32(&iphdr->dest) >> 16;
+#endif /* CHECKSUM_GEN_IP_INLINE */
+
+    IPH_VHLTOS_SET(iphdr, 4, ip_hlen / 4, tos);
+#if CHECKSUM_GEN_IP_INLINE
+    chk_sum += iphdr->_v_hl_tos;
+#endif /* CHECKSUM_GEN_IP_INLINE */
+    IPH_LEN_SET(iphdr, htons(p->tot_len));
+#if CHECKSUM_GEN_IP_INLINE
+    chk_sum += iphdr->_len;
+#endif /* CHECKSUM_GEN_IP_INLINE */
+    IPH_OFFSET_SET(iphdr, 0);
+    IPH_ID_SET(iphdr, htons(ip_id));
+#if CHECKSUM_GEN_IP_INLINE
+    chk_sum += iphdr->_id;
+#endif /* CHECKSUM_GEN_IP_INLINE */
+    ++ip_id;
+
+    if (ip_addr_isany(src)) {
+      ip_addr_copy(iphdr->src, netif->ip_addr);
+    } else {
+      /* src cannot be NULL here */
+      ip_addr_copy(iphdr->src, *src);
+    }
+
+#if CHECKSUM_GEN_IP_INLINE
+    chk_sum += ip4_addr_get_u32(&iphdr->src) & 0xFFFF;
+    chk_sum += ip4_addr_get_u32(&iphdr->src) >> 16;
+    chk_sum = (chk_sum >> 16) + (chk_sum & 0xFFFF);
+    chk_sum = (chk_sum >> 16) + chk_sum;
+    chk_sum = ~chk_sum;
+    iphdr->_chksum = chk_sum; /* network order */
+#else /* CHECKSUM_GEN_IP_INLINE */
+    IPH_CHKSUM_SET(iphdr, 0);
+#if CHECKSUM_GEN_IP
+    IPH_CHKSUM_SET(iphdr, inet_chksum(iphdr, ip_hlen));
+#endif
+#endif /* CHECKSUM_GEN_IP_INLINE */
+  } else {
+    /* IP header already included in p */
+    iphdr = (struct ip_hdr *)p->payload;
+    ip_addr_copy(dest_addr, iphdr->dest);
+    dest = &dest_addr;
+  }
+
+  IP_STATS_INC(ip.xmit);
+
+  LWIP_DEBUGF(IP_DEBUG, ("ip_output_if: %c%c%"U16_F"\n", netif->name[0], netif->name[1], netif->num));
+  ip_debug_print(p);
+
+#if ENABLE_LOOPBACK
+  if (ip_addr_cmp(dest, &netif->ip_addr)) {
+    /* Packet to self, enqueue it for loopback */
+    LWIP_DEBUGF(IP_DEBUG, ("netif_loop_output()"));
+    return netif_loop_output(netif, p, dest);
+  }
+#if LWIP_IGMP
+  if ((p->flags & PBUF_FLAG_MCASTLOOP) != 0) {
+    netif_loop_output(netif, p, dest);
+  }
+#endif /* LWIP_IGMP */
+#endif /* ENABLE_LOOPBACK */
+#if IP_FRAG
+  /* don't fragment if interface has mtu set to 0 [loopif] */
+  if (netif->mtu && (p->tot_len > netif->mtu)) {
+    return ip_frag(p, netif, dest);
+  }
+#endif /* IP_FRAG */
+
+  LWIP_DEBUGF(IP_DEBUG, ("netif->output()"));
+  return netif->output(netif, p, dest);
+}
+
+/**
+ * Simple interface to ip_output_if. It finds the outgoing network
+ * interface and calls upon ip_output_if to do the actual work.
+ *
+ * @param p the packet to send (p->payload points to the data, e.g. next
+            protocol header; if dest == IP_HDRINCL, p already includes an IP
+            header and p->payload points to that IP header)
+ * @param src the source IP address to send from (if src == IP_ADDR_ANY, the
+ *         IP  address of the netif used to send is used as source address)
+ * @param dest the destination IP address to send the packet to
+ * @param ttl the TTL value to be set in the IP header
+ * @param tos the TOS value to be set in the IP header
+ * @param proto the PROTOCOL to be set in the IP header
+ *
+ * @return ERR_RTE if no route is found
+ *         see ip_output_if() for more return values
+ */
+err_t
+ip_output(struct pbuf *p, ip_addr_t *src, ip_addr_t *dest,
+          u8_t ttl, u8_t tos, u8_t proto)
+{
+  struct netif *netif;
+
+  /* pbufs passed to IP must have a ref-count of 1 as their payload pointer
+     gets altered as the packet is passed down the stack */
+  LWIP_ASSERT("p->ref == 1", p->ref == 1);
+
+  if ((netif = ip_route(dest)) == NULL) {
+    LWIP_DEBUGF(IP_DEBUG, ("ip_output: No route to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
+      ip4_addr1_16(dest), ip4_addr2_16(dest), ip4_addr3_16(dest), ip4_addr4_16(dest)));
+    IP_STATS_INC(ip.rterr);
+    return ERR_RTE;
+  }
+
+  return ip_output_if(p, src, dest, ttl, tos, proto, netif);
+}
+
+#if LWIP_NETIF_HWADDRHINT
+/** Like ip_output, but takes and addr_hint pointer that is passed on to netif->addr_hint
+ *  before calling ip_output_if.
+ *
+ * @param p the packet to send (p->payload points to the data, e.g. next
+            protocol header; if dest == IP_HDRINCL, p already includes an IP
+            header and p->payload points to that IP header)
+ * @param src the source IP address to send from (if src == IP_ADDR_ANY, the
+ *         IP  address of the netif used to send is used as source address)
+ * @param dest the destination IP address to send the packet to
+ * @param ttl the TTL value to be set in the IP header
+ * @param tos the TOS value to be set in the IP header
+ * @param proto the PROTOCOL to be set in the IP header
+ * @param addr_hint address hint pointer set to netif->addr_hint before
+ *        calling ip_output_if()
+ *
+ * @return ERR_RTE if no route is found
+ *         see ip_output_if() for more return values
+ */
+err_t
+ip_output_hinted(struct pbuf *p, ip_addr_t *src, ip_addr_t *dest,
+          u8_t ttl, u8_t tos, u8_t proto, u8_t *addr_hint)
+{
+  struct netif *netif;
+  err_t err;
+
+  /* pbufs passed to IP must have a ref-count of 1 as their payload pointer
+     gets altered as the packet is passed down the stack */
+  LWIP_ASSERT("p->ref == 1", p->ref == 1);
+
+  if ((netif = ip_route(dest)) == NULL) {
+    LWIP_DEBUGF(IP_DEBUG, ("ip_output: No route to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
+      ip4_addr1_16(dest), ip4_addr2_16(dest), ip4_addr3_16(dest), ip4_addr4_16(dest)));
+    IP_STATS_INC(ip.rterr);
+    return ERR_RTE;
+  }
+
+  netif->addr_hint = addr_hint;
+  err = ip_output_if(p, src, dest, ttl, tos, proto, netif);
+  netif->addr_hint = NULL;
+
+  return err;
+}
+#endif /* LWIP_NETIF_HWADDRHINT*/
+
+#if IP_DEBUG
+/* Print an IP header by using LWIP_DEBUGF
+ * @param p an IP packet, p->payload pointing to the IP header
+ */
+void
+ip_debug_print(struct pbuf *p)
+{
+  struct ip_hdr *iphdr = (struct ip_hdr *)p->payload;
+  u8_t *payload;
+
+  payload = (u8_t *)iphdr + IP_HLEN;
+
+  LWIP_DEBUGF(IP_DEBUG, ("IP header:\n"));
+  LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n"));
+  LWIP_DEBUGF(IP_DEBUG, ("|%2"S16_F" |%2"S16_F" |  0x%02"X16_F" |     %5"U16_F"     | (v, hl, tos, len)\n",
+                    IPH_V(iphdr),
+                    IPH_HL(iphdr),
+                    IPH_TOS(iphdr),
+                    ntohs(IPH_LEN(iphdr))));
+  LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n"));
+  LWIP_DEBUGF(IP_DEBUG, ("|    %5"U16_F"      |%"U16_F"%"U16_F"%"U16_F"|    %4"U16_F"   | (id, flags, offset)\n",
+                    ntohs(IPH_ID(iphdr)),
+                    ntohs(IPH_OFFSET(iphdr)) >> 15 & 1,
+                    ntohs(IPH_OFFSET(iphdr)) >> 14 & 1,
+                    ntohs(IPH_OFFSET(iphdr)) >> 13 & 1,
+                    ntohs(IPH_OFFSET(iphdr)) & IP_OFFMASK));
+  LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n"));
+  LWIP_DEBUGF(IP_DEBUG, ("|  %3"U16_F"  |  %3"U16_F"  |    0x%04"X16_F"     | (ttl, proto, chksum)\n",
+                    IPH_TTL(iphdr),
+                    IPH_PROTO(iphdr),
+                    ntohs(IPH_CHKSUM(iphdr))));
+  LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n"));
+  LWIP_DEBUGF(IP_DEBUG, ("|  %3"U16_F"  |  %3"U16_F"  |  %3"U16_F"  |  %3"U16_F"  | (src)\n",
+                    ip4_addr1_16(&iphdr->src),
+                    ip4_addr2_16(&iphdr->src),
+                    ip4_addr3_16(&iphdr->src),
+                    ip4_addr4_16(&iphdr->src)));
+  LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n"));
+  LWIP_DEBUGF(IP_DEBUG, ("|  %3"U16_F"  |  %3"U16_F"  |  %3"U16_F"  |  %3"U16_F"  | (dest)\n",
+                    ip4_addr1_16(&iphdr->dest),
+                    ip4_addr2_16(&iphdr->dest),
+                    ip4_addr3_16(&iphdr->dest),
+                    ip4_addr4_16(&iphdr->dest)));
+  LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n"));
+}
+#endif /* IP_DEBUG */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/core/ipv4/ip_addr.c	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,312 @@
+/**
+ * @file
+ * This is the IPv4 address tools implementation.
+ *
+ */
+
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+
+#include "lwip/opt.h"
+#include "lwip/ip_addr.h"
+#include "lwip/netif.h"
+
+/* used by IP_ADDR_ANY and IP_ADDR_BROADCAST in ip_addr.h */
+const ip_addr_t ip_addr_any = { IPADDR_ANY };
+const ip_addr_t ip_addr_broadcast = { IPADDR_BROADCAST };
+
+/**
+ * Determine if an address is a broadcast address on a network interface 
+ * 
+ * @param addr address to be checked
+ * @param netif the network interface against which the address is checked
+ * @return returns non-zero if the address is a broadcast address
+ */
+u8_t
+ip4_addr_isbroadcast(u32_t addr, const struct netif *netif)
+{
+  ip_addr_t ipaddr;
+  ip4_addr_set_u32(&ipaddr, addr);
+
+  /* all ones (broadcast) or all zeroes (old skool broadcast) */
+  if ((~addr == IPADDR_ANY) ||
+      (addr == IPADDR_ANY)) {
+    return 1;
+  /* no broadcast support on this network interface? */
+  } else if ((netif->flags & NETIF_FLAG_BROADCAST) == 0) {
+    /* the given address cannot be a broadcast address
+     * nor can we check against any broadcast addresses */
+    return 0;
+  /* address matches network interface address exactly? => no broadcast */
+  } else if (addr == ip4_addr_get_u32(&netif->ip_addr)) {
+    return 0;
+  /*  on the same (sub) network... */
+  } else if (ip_addr_netcmp(&ipaddr, &(netif->ip_addr), &(netif->netmask))
+         /* ...and host identifier bits are all ones? =>... */
+          && ((addr & ~ip4_addr_get_u32(&netif->netmask)) ==
+           (IPADDR_BROADCAST & ~ip4_addr_get_u32(&netif->netmask)))) {
+    /* => network broadcast address */
+    return 1;
+  } else {
+    return 0;
+  }
+}
+
+/** Checks if a netmask is valid (starting with ones, then only zeros)
+ *
+ * @param netmask the IPv4 netmask to check (in network byte order!)
+ * @return 1 if the netmask is valid, 0 if it is not
+ */
+u8_t
+ip4_addr_netmask_valid(u32_t netmask)
+{
+  u32_t mask;
+  u32_t nm_hostorder = lwip_htonl(netmask);
+
+  /* first, check for the first zero */
+  for (mask = 1U << 31 ; mask != 0; mask >>= 1) {
+    if ((nm_hostorder & mask) == 0) {
+      break;
+    }
+  }
+  /* then check that there is no one */
+  for (; mask != 0; mask >>= 1) {
+    if ((nm_hostorder & mask) != 0) {
+      /* there is a one after the first zero -> invalid */
+      return 0;
+    }
+  }
+  /* no one after the first zero -> valid */
+  return 1;
+}
+
+/* Here for now until needed in other places in lwIP */
+#ifndef isprint
+#define in_range(c, lo, up)  ((u8_t)c >= lo && (u8_t)c <= up)
+#define isprint(c)           in_range(c, 0x20, 0x7f)
+#define isdigit(c)           in_range(c, '0', '9')
+#define isxdigit(c)          (isdigit(c) || in_range(c, 'a', 'f') || in_range(c, 'A', 'F'))
+#define islower(c)           in_range(c, 'a', 'z')
+#define isspace(c)           (c == ' ' || c == '\f' || c == '\n' || c == '\r' || c == '\t' || c == '\v')
+#endif
+
+/**
+ * Ascii internet address interpretation routine.
+ * The value returned is in network order.
+ *
+ * @param cp IP address in ascii represenation (e.g. "127.0.0.1")
+ * @return ip address in network order
+ */
+u32_t
+ipaddr_addr(const char *cp)
+{
+  ip_addr_t val;
+
+  if (ipaddr_aton(cp, &val)) {
+    return ip4_addr_get_u32(&val);
+  }
+  return (IPADDR_NONE);
+}
+
+/**
+ * Check whether "cp" is a valid ascii representation
+ * of an Internet address and convert to a binary address.
+ * Returns 1 if the address is valid, 0 if not.
+ * This replaces inet_addr, the return value from which
+ * cannot distinguish between failure and a local broadcast address.
+ *
+ * @param cp IP address in ascii represenation (e.g. "127.0.0.1")
+ * @param addr pointer to which to save the ip address in network order
+ * @return 1 if cp could be converted to addr, 0 on failure
+ */
+int
+ipaddr_aton(const char *cp, ip_addr_t *addr)
+{
+  u32_t val;
+  u8_t base;
+  char c;
+  u32_t parts[4];
+  u32_t *pp = parts;
+
+  c = *cp;
+  for (;;) {
+    /*
+     * Collect number up to ``.''.
+     * Values are specified as for C:
+     * 0x=hex, 0=octal, 1-9=decimal.
+     */
+    if (!isdigit(c))
+      return (0);
+    val = 0;
+    base = 10;
+    if (c == '0') {
+      c = *++cp;
+      if (c == 'x' || c == 'X') {
+        base = 16;
+        c = *++cp;
+      } else
+        base = 8;
+    }
+    for (;;) {
+      if (isdigit(c)) {
+        val = (val * base) + (int)(c - '0');
+        c = *++cp;
+      } else if (base == 16 && isxdigit(c)) {
+        val = (val << 4) | (int)(c + 10 - (islower(c) ? 'a' : 'A'));
+        c = *++cp;
+      } else
+        break;
+    }
+    if (c == '.') {
+      /*
+       * Internet format:
+       *  a.b.c.d
+       *  a.b.c   (with c treated as 16 bits)
+       *  a.b (with b treated as 24 bits)
+       */
+      if (pp >= parts + 3) {
+        return (0);
+      }
+      *pp++ = val;
+      c = *++cp;
+    } else
+      break;
+  }
+  /*
+   * Check for trailing characters.
+   */
+  if (c != '\0' && !isspace(c)) {
+    return (0);
+  }
+  /*
+   * Concoct the address according to
+   * the number of parts specified.
+   */
+  switch (pp - parts + 1) {
+
+  case 0:
+    return (0);       /* initial nondigit */
+
+  case 1:             /* a -- 32 bits */
+    break;
+
+  case 2:             /* a.b -- 8.24 bits */
+    if (val > 0xffffffUL) {
+      return (0);
+    }
+    val |= parts[0] << 24;
+    break;
+
+  case 3:             /* a.b.c -- 8.8.16 bits */
+    if (val > 0xffff) {
+      return (0);
+    }
+    val |= (parts[0] << 24) | (parts[1] << 16);
+    break;
+
+  case 4:             /* a.b.c.d -- 8.8.8.8 bits */
+    if (val > 0xff) {
+      return (0);
+    }
+    val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8);
+    break;
+  default:
+    LWIP_ASSERT("unhandled", 0);
+    break;
+  }
+  if (addr) {
+    ip4_addr_set_u32(addr, htonl(val));
+  }
+  return (1);
+}
+
+/**
+ * Convert numeric IP address into decimal dotted ASCII representation.
+ * returns ptr to static buffer; not reentrant!
+ *
+ * @param addr ip address in network order to convert
+ * @return pointer to a global static (!) buffer that holds the ASCII
+ *         represenation of addr
+ */
+char *
+ipaddr_ntoa(const ip_addr_t *addr)
+{
+  static char str[16];
+  return ipaddr_ntoa_r(addr, str, 16);
+}
+
+/**
+ * Same as ipaddr_ntoa, but reentrant since a user-supplied buffer is used.
+ *
+ * @param addr ip address in network order to convert
+ * @param buf target buffer where the string is stored
+ * @param buflen length of buf
+ * @return either pointer to buf which now holds the ASCII
+ *         representation of addr or NULL if buf was too small
+ */
+char *ipaddr_ntoa_r(const ip_addr_t *addr, char *buf, int buflen)
+{
+  u32_t s_addr;
+  char inv[3];
+  char *rp;
+  u8_t *ap;
+  u8_t rem;
+  u8_t n;
+  u8_t i;
+  int len = 0;
+
+  s_addr = ip4_addr_get_u32(addr);
+
+  rp = buf;
+  ap = (u8_t *)&s_addr;
+  for(n = 0; n < 4; n++) {
+    i = 0;
+    do {
+      rem = *ap % (u8_t)10;
+      *ap /= (u8_t)10;
+      inv[i++] = '0' + rem;
+    } while(*ap);
+    while(i--) {
+      if (len++ >= buflen) {
+        return NULL;
+      }
+      *rp++ = inv[i];
+    }
+    if (len++ >= buflen) {
+      return NULL;
+    }
+    *rp++ = '.';
+    ap++;
+  }
+  *--rp = 0;
+  return buf;
+}
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/core/ipv4/ip_frag.c	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,863 @@
+/**
+ * @file
+ * This is the IPv4 packet segmentation and reassembly implementation.
+ *
+ */
+
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Jani Monoses <jani@iv.ro> 
+ *         Simon Goldschmidt
+ * original reassembly code by Adam Dunkels <adam@sics.se>
+ * 
+ */
+
+#include "lwip/opt.h"
+#include "lwip/ip_frag.h"
+#include "lwip/def.h"
+#include "lwip/inet_chksum.h"
+#include "lwip/netif.h"
+#include "lwip/snmp.h"
+#include "lwip/stats.h"
+#include "lwip/icmp.h"
+
+#include <string.h>
+
+#if IP_REASSEMBLY
+/**
+ * The IP reassembly code currently has the following limitations:
+ * - IP header options are not supported
+ * - fragments must not overlap (e.g. due to different routes),
+ *   currently, overlapping or duplicate fragments are thrown away
+ *   if IP_REASS_CHECK_OVERLAP=1 (the default)!
+ *
+ * @todo: work with IP header options
+ */
+
+/** Setting this to 0, you can turn off checking the fragments for overlapping
+ * regions. The code gets a little smaller. Only use this if you know that
+ * overlapping won't occur on your network! */
+#ifndef IP_REASS_CHECK_OVERLAP
+#define IP_REASS_CHECK_OVERLAP 1
+#endif /* IP_REASS_CHECK_OVERLAP */
+
+/** Set to 0 to prevent freeing the oldest datagram when the reassembly buffer is
+ * full (IP_REASS_MAX_PBUFS pbufs are enqueued). The code gets a little smaller.
+ * Datagrams will be freed by timeout only. Especially useful when MEMP_NUM_REASSDATA
+ * is set to 1, so one datagram can be reassembled at a time, only. */
+#ifndef IP_REASS_FREE_OLDEST
+#define IP_REASS_FREE_OLDEST 1
+#endif /* IP_REASS_FREE_OLDEST */
+
+#define IP_REASS_FLAG_LASTFRAG 0x01
+
+/** This is a helper struct which holds the starting
+ * offset and the ending offset of this fragment to
+ * easily chain the fragments.
+ * It has the same packing requirements as the IP header, since it replaces
+ * the IP header in memory in incoming fragments (after copying it) to keep
+ * track of the various fragments. (-> If the IP header doesn't need packing,
+ * this struct doesn't need packing, too.)
+ */
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/bpstruct.h"
+#endif
+PACK_STRUCT_BEGIN
+struct ip_reass_helper {
+  PACK_STRUCT_FIELD(struct pbuf *next_pbuf);
+  PACK_STRUCT_FIELD(u16_t start);
+  PACK_STRUCT_FIELD(u16_t end);
+} PACK_STRUCT_STRUCT;
+PACK_STRUCT_END
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/epstruct.h"
+#endif
+
+#define IP_ADDRESSES_AND_ID_MATCH(iphdrA, iphdrB)  \
+  (ip_addr_cmp(&(iphdrA)->src, &(iphdrB)->src) && \
+   ip_addr_cmp(&(iphdrA)->dest, &(iphdrB)->dest) && \
+   IPH_ID(iphdrA) == IPH_ID(iphdrB)) ? 1 : 0
+
+/* global variables */
+static struct ip_reassdata *reassdatagrams;
+static u16_t ip_reass_pbufcount;
+
+/* function prototypes */
+static void ip_reass_dequeue_datagram(struct ip_reassdata *ipr, struct ip_reassdata *prev);
+static int ip_reass_free_complete_datagram(struct ip_reassdata *ipr, struct ip_reassdata *prev);
+
+/**
+ * Reassembly timer base function
+ * for both NO_SYS == 0 and 1 (!).
+ *
+ * Should be called every 1000 msec (defined by IP_TMR_INTERVAL).
+ */
+void
+ip_reass_tmr(void)
+{
+  struct ip_reassdata *r, *prev = NULL;
+
+  r = reassdatagrams;
+  while (r != NULL) {
+    /* Decrement the timer. Once it reaches 0,
+     * clean up the incomplete fragment assembly */
+    if (r->timer > 0) {
+      r->timer--;
+      LWIP_DEBUGF(IP_REASS_DEBUG, ("ip_reass_tmr: timer dec %"U16_F"\n",(u16_t)r->timer));
+      prev = r;
+      r = r->next;
+    } else {
+      /* reassembly timed out */
+      struct ip_reassdata *tmp;
+      LWIP_DEBUGF(IP_REASS_DEBUG, ("ip_reass_tmr: timer timed out\n"));
+      tmp = r;
+      /* get the next pointer before freeing */
+      r = r->next;
+      /* free the helper struct and all enqueued pbufs */
+      ip_reass_free_complete_datagram(tmp, prev);
+     }
+   }
+}
+
+/**
+ * Free a datagram (struct ip_reassdata) and all its pbufs.
+ * Updates the total count of enqueued pbufs (ip_reass_pbufcount),
+ * SNMP counters and sends an ICMP time exceeded packet.
+ *
+ * @param ipr datagram to free
+ * @param prev the previous datagram in the linked list
+ * @return the number of pbufs freed
+ */
+static int
+ip_reass_free_complete_datagram(struct ip_reassdata *ipr, struct ip_reassdata *prev)
+{
+  u16_t pbufs_freed = 0;
+  u8_t clen;
+  struct pbuf *p;
+  struct ip_reass_helper *iprh;
+
+  LWIP_ASSERT("prev != ipr", prev != ipr);
+  if (prev != NULL) {
+    LWIP_ASSERT("prev->next == ipr", prev->next == ipr);
+  }
+
+  snmp_inc_ipreasmfails();
+#if LWIP_ICMP
+  iprh = (struct ip_reass_helper *)ipr->p->payload;
+  if (iprh->start == 0) {
+    /* The first fragment was received, send ICMP time exceeded. */
+    /* First, de-queue the first pbuf from r->p. */
+    p = ipr->p;
+    ipr->p = iprh->next_pbuf;
+    /* Then, copy the original header into it. */
+    SMEMCPY(p->payload, &ipr->iphdr, IP_HLEN);
+    icmp_time_exceeded(p, ICMP_TE_FRAG);
+    clen = pbuf_clen(p);
+    LWIP_ASSERT("pbufs_freed + clen <= 0xffff", pbufs_freed + clen <= 0xffff);
+    pbufs_freed += clen;
+    pbuf_free(p);
+  }
+#endif /* LWIP_ICMP */
+
+  /* First, free all received pbufs.  The individual pbufs need to be released 
+     separately as they have not yet been chained */
+  p = ipr->p;
+  while (p != NULL) {
+    struct pbuf *pcur;
+    iprh = (struct ip_reass_helper *)p->payload;
+    pcur = p;
+    /* get the next pointer before freeing */
+    p = iprh->next_pbuf;
+    clen = pbuf_clen(pcur);
+    LWIP_ASSERT("pbufs_freed + clen <= 0xffff", pbufs_freed + clen <= 0xffff);
+    pbufs_freed += clen;
+    pbuf_free(pcur);
+  }
+  /* Then, unchain the struct ip_reassdata from the list and free it. */
+  ip_reass_dequeue_datagram(ipr, prev);
+  LWIP_ASSERT("ip_reass_pbufcount >= clen", ip_reass_pbufcount >= pbufs_freed);
+  ip_reass_pbufcount -= pbufs_freed;
+
+  return pbufs_freed;
+}
+
+#if IP_REASS_FREE_OLDEST
+/**
+ * Free the oldest datagram to make room for enqueueing new fragments.
+ * The datagram 'fraghdr' belongs to is not freed!
+ *
+ * @param fraghdr IP header of the current fragment
+ * @param pbufs_needed number of pbufs needed to enqueue
+ *        (used for freeing other datagrams if not enough space)
+ * @return the number of pbufs freed
+ */
+static int
+ip_reass_remove_oldest_datagram(struct ip_hdr *fraghdr, int pbufs_needed)
+{
+  /* @todo Can't we simply remove the last datagram in the
+   *       linked list behind reassdatagrams?
+   */
+  struct ip_reassdata *r, *oldest, *prev;
+  int pbufs_freed = 0, pbufs_freed_current;
+  int other_datagrams;
+
+  /* Free datagrams until being allowed to enqueue 'pbufs_needed' pbufs,
+   * but don't free the datagram that 'fraghdr' belongs to! */
+  do {
+    oldest = NULL;
+    prev = NULL;
+    other_datagrams = 0;
+    r = reassdatagrams;
+    while (r != NULL) {
+      if (!IP_ADDRESSES_AND_ID_MATCH(&r->iphdr, fraghdr)) {
+        /* Not the same datagram as fraghdr */
+        other_datagrams++;
+        if (oldest == NULL) {
+          oldest = r;
+        } else if (r->timer <= oldest->timer) {
+          /* older than the previous oldest */
+          oldest = r;
+        }
+      }
+      if (r->next != NULL) {
+        prev = r;
+      }
+      r = r->next;
+    }
+    if (oldest != NULL) {
+      pbufs_freed_current = ip_reass_free_complete_datagram(oldest, prev);
+      pbufs_freed += pbufs_freed_current;
+    }
+  } while ((pbufs_freed < pbufs_needed) && (other_datagrams > 1));
+  return pbufs_freed;
+}
+#endif /* IP_REASS_FREE_OLDEST */
+
+/**
+ * Enqueues a new fragment into the fragment queue
+ * @param fraghdr points to the new fragments IP hdr
+ * @param clen number of pbufs needed to enqueue (used for freeing other datagrams if not enough space)
+ * @return A pointer to the queue location into which the fragment was enqueued
+ */
+static struct ip_reassdata*
+ip_reass_enqueue_new_datagram(struct ip_hdr *fraghdr, int clen)
+{
+  struct ip_reassdata* ipr;
+  /* No matching previous fragment found, allocate a new reassdata struct */
+  ipr = (struct ip_reassdata *)memp_malloc(MEMP_REASSDATA);
+  if (ipr == NULL) {
+#if IP_REASS_FREE_OLDEST
+    if (ip_reass_remove_oldest_datagram(fraghdr, clen) >= clen) {
+      ipr = (struct ip_reassdata *)memp_malloc(MEMP_REASSDATA);
+    }
+    if (ipr == NULL)
+#endif /* IP_REASS_FREE_OLDEST */
+    {
+      IPFRAG_STATS_INC(ip_frag.memerr);
+      LWIP_DEBUGF(IP_REASS_DEBUG,("Failed to alloc reassdata struct\n"));
+      return NULL;
+    }
+  }
+  memset(ipr, 0, sizeof(struct ip_reassdata));
+  ipr->timer = IP_REASS_MAXAGE;
+
+  /* enqueue the new structure to the front of the list */
+  ipr->next = reassdatagrams;
+  reassdatagrams = ipr;
+  /* copy the ip header for later tests and input */
+  /* @todo: no ip options supported? */
+  SMEMCPY(&(ipr->iphdr), fraghdr, IP_HLEN);
+  return ipr;
+}
+
+/**
+ * Dequeues a datagram from the datagram queue. Doesn't deallocate the pbufs.
+ * @param ipr points to the queue entry to dequeue
+ */
+static void
+ip_reass_dequeue_datagram(struct ip_reassdata *ipr, struct ip_reassdata *prev)
+{
+  
+  /* dequeue the reass struct  */
+  if (reassdatagrams == ipr) {
+    /* it was the first in the list */
+    reassdatagrams = ipr->next;
+  } else {
+    /* it wasn't the first, so it must have a valid 'prev' */
+    LWIP_ASSERT("sanity check linked list", prev != NULL);
+    prev->next = ipr->next;
+  }
+
+  /* now we can free the ip_reass struct */
+  memp_free(MEMP_REASSDATA, ipr);
+}
+
+/**
+ * Chain a new pbuf into the pbuf list that composes the datagram.  The pbuf list
+ * will grow over time as  new pbufs are rx.
+ * Also checks that the datagram passes basic continuity checks (if the last
+ * fragment was received at least once).
+ * @param root_p points to the 'root' pbuf for the current datagram being assembled.
+ * @param new_p points to the pbuf for the current fragment
+ * @return 0 if invalid, >0 otherwise
+ */
+static int
+ip_reass_chain_frag_into_datagram_and_validate(struct ip_reassdata *ipr, struct pbuf *new_p)
+{
+  struct ip_reass_helper *iprh, *iprh_tmp, *iprh_prev=NULL;
+  struct pbuf *q;
+  u16_t offset,len;
+  struct ip_hdr *fraghdr;
+  int valid = 1;
+
+  /* Extract length and fragment offset from current fragment */
+  fraghdr = (struct ip_hdr*)new_p->payload; 
+  len = ntohs(IPH_LEN(fraghdr)) - IPH_HL(fraghdr) * 4;
+  offset = (ntohs(IPH_OFFSET(fraghdr)) & IP_OFFMASK) * 8;
+
+  /* overwrite the fragment's ip header from the pbuf with our helper struct,
+   * and setup the embedded helper structure. */
+  /* make sure the struct ip_reass_helper fits into the IP header */
+  LWIP_ASSERT("sizeof(struct ip_reass_helper) <= IP_HLEN",
+              sizeof(struct ip_reass_helper) <= IP_HLEN);
+  iprh = (struct ip_reass_helper*)new_p->payload;
+  iprh->next_pbuf = NULL;
+  iprh->start = offset;
+  iprh->end = offset + len;
+
+  /* Iterate through until we either get to the end of the list (append),
+   * or we find on with a larger offset (insert). */
+  for (q = ipr->p; q != NULL;) {
+    iprh_tmp = (struct ip_reass_helper*)q->payload;
+    if (iprh->start < iprh_tmp->start) {
+      /* the new pbuf should be inserted before this */
+      iprh->next_pbuf = q;
+      if (iprh_prev != NULL) {
+        /* not the fragment with the lowest offset */
+#if IP_REASS_CHECK_OVERLAP
+        if ((iprh->start < iprh_prev->end) || (iprh->end > iprh_tmp->start)) {
+          /* fragment overlaps with previous or following, throw away */
+          goto freepbuf;
+        }
+#endif /* IP_REASS_CHECK_OVERLAP */
+        iprh_prev->next_pbuf = new_p;
+      } else {
+        /* fragment with the lowest offset */
+        ipr->p = new_p;
+      }
+      break;
+    } else if(iprh->start == iprh_tmp->start) {
+      /* received the same datagram twice: no need to keep the datagram */
+      goto freepbuf;
+#if IP_REASS_CHECK_OVERLAP
+    } else if(iprh->start < iprh_tmp->end) {
+      /* overlap: no need to keep the new datagram */
+      goto freepbuf;
+#endif /* IP_REASS_CHECK_OVERLAP */
+    } else {
+      /* Check if the fragments received so far have no wholes. */
+      if (iprh_prev != NULL) {
+        if (iprh_prev->end != iprh_tmp->start) {
+          /* There is a fragment missing between the current
+           * and the previous fragment */
+          valid = 0;
+        }
+      }
+    }
+    q = iprh_tmp->next_pbuf;
+    iprh_prev = iprh_tmp;
+  }
+
+  /* If q is NULL, then we made it to the end of the list. Determine what to do now */
+  if (q == NULL) {
+    if (iprh_prev != NULL) {
+      /* this is (for now), the fragment with the highest offset:
+       * chain it to the last fragment */
+#if IP_REASS_CHECK_OVERLAP
+      LWIP_ASSERT("check fragments don't overlap", iprh_prev->end <= iprh->start);
+#endif /* IP_REASS_CHECK_OVERLAP */
+      iprh_prev->next_pbuf = new_p;
+      if (iprh_prev->end != iprh->start) {
+        valid = 0;
+      }
+    } else {
+#if IP_REASS_CHECK_OVERLAP
+      LWIP_ASSERT("no previous fragment, this must be the first fragment!",
+        ipr->p == NULL);
+#endif /* IP_REASS_CHECK_OVERLAP */
+      /* this is the first fragment we ever received for this ip datagram */
+      ipr->p = new_p;
+    }
+  }
+
+  /* At this point, the validation part begins: */
+  /* If we already received the last fragment */
+  if ((ipr->flags & IP_REASS_FLAG_LASTFRAG) != 0) {
+    /* and had no wholes so far */
+    if (valid) {
+      /* then check if the rest of the fragments is here */
+      /* Check if the queue starts with the first datagram */
+      if (((struct ip_reass_helper*)ipr->p->payload)->start != 0) {
+        valid = 0;
+      } else {
+        /* and check that there are no wholes after this datagram */
+        iprh_prev = iprh;
+        q = iprh->next_pbuf;
+        while (q != NULL) {
+          iprh = (struct ip_reass_helper*)q->payload;
+          if (iprh_prev->end != iprh->start) {
+            valid = 0;
+            break;
+          }
+          iprh_prev = iprh;
+          q = iprh->next_pbuf;
+        }
+        /* if still valid, all fragments are received
+         * (because to the MF==0 already arrived */
+        if (valid) {
+          LWIP_ASSERT("sanity check", ipr->p != NULL);
+          LWIP_ASSERT("sanity check",
+            ((struct ip_reass_helper*)ipr->p->payload) != iprh);
+          LWIP_ASSERT("validate_datagram:next_pbuf!=NULL",
+            iprh->next_pbuf == NULL);
+          LWIP_ASSERT("validate_datagram:datagram end!=datagram len",
+            iprh->end == ipr->datagram_len);
+        }
+      }
+    }
+    /* If valid is 0 here, there are some fragments missing in the middle
+     * (since MF == 0 has already arrived). Such datagrams simply time out if
+     * no more fragments are received... */
+    return valid;
+  }
+  /* If we come here, not all fragments were received, yet! */
+  return 0; /* not yet valid! */
+#if IP_REASS_CHECK_OVERLAP
+freepbuf:
+  ip_reass_pbufcount -= pbuf_clen(new_p);
+  pbuf_free(new_p);
+  return 0;
+#endif /* IP_REASS_CHECK_OVERLAP */
+}
+
+/**
+ * Reassembles incoming IP fragments into an IP datagram.
+ *
+ * @param p points to a pbuf chain of the fragment
+ * @return NULL if reassembly is incomplete, ? otherwise
+ */
+struct pbuf *
+ip_reass(struct pbuf *p)
+{
+  struct pbuf *r;
+  struct ip_hdr *fraghdr;
+  struct ip_reassdata *ipr;
+  struct ip_reass_helper *iprh;
+  u16_t offset, len;
+  u8_t clen;
+  struct ip_reassdata *ipr_prev = NULL;
+
+  IPFRAG_STATS_INC(ip_frag.recv);
+  snmp_inc_ipreasmreqds();
+
+  fraghdr = (struct ip_hdr*)p->payload;
+
+  if ((IPH_HL(fraghdr) * 4) != IP_HLEN) {
+    LWIP_DEBUGF(IP_REASS_DEBUG,("ip_reass: IP options currently not supported!\n"));
+    IPFRAG_STATS_INC(ip_frag.err);
+    goto nullreturn;
+  }
+
+  offset = (ntohs(IPH_OFFSET(fraghdr)) & IP_OFFMASK) * 8;
+  len = ntohs(IPH_LEN(fraghdr)) - IPH_HL(fraghdr) * 4;
+
+  /* Check if we are allowed to enqueue more datagrams. */
+  clen = pbuf_clen(p);
+  if ((ip_reass_pbufcount + clen) > IP_REASS_MAX_PBUFS) {
+#if IP_REASS_FREE_OLDEST
+    if (!ip_reass_remove_oldest_datagram(fraghdr, clen) ||
+        ((ip_reass_pbufcount + clen) > IP_REASS_MAX_PBUFS))
+#endif /* IP_REASS_FREE_OLDEST */
+    {
+      /* No datagram could be freed and still too many pbufs enqueued */
+      LWIP_DEBUGF(IP_REASS_DEBUG,("ip_reass: Overflow condition: pbufct=%d, clen=%d, MAX=%d\n",
+        ip_reass_pbufcount, clen, IP_REASS_MAX_PBUFS));
+      IPFRAG_STATS_INC(ip_frag.memerr);
+      /* @todo: send ICMP time exceeded here? */
+      /* drop this pbuf */
+      goto nullreturn;
+    }
+  }
+
+  /* Look for the datagram the fragment belongs to in the current datagram queue,
+   * remembering the previous in the queue for later dequeueing. */
+  for (ipr = reassdatagrams; ipr != NULL; ipr = ipr->next) {
+    /* Check if the incoming fragment matches the one currently present
+       in the reassembly buffer. If so, we proceed with copying the
+       fragment into the buffer. */
+    if (IP_ADDRESSES_AND_ID_MATCH(&ipr->iphdr, fraghdr)) {
+      LWIP_DEBUGF(IP_REASS_DEBUG, ("ip_reass: matching previous fragment ID=%"X16_F"\n",
+        ntohs(IPH_ID(fraghdr))));
+      IPFRAG_STATS_INC(ip_frag.cachehit);
+      break;
+    }
+    ipr_prev = ipr;
+  }
+
+  if (ipr == NULL) {
+  /* Enqueue a new datagram into the datagram queue */
+    ipr = ip_reass_enqueue_new_datagram(fraghdr, clen);
+    /* Bail if unable to enqueue */
+    if(ipr == NULL) {
+      goto nullreturn;
+    }
+  } else {
+    if (((ntohs(IPH_OFFSET(fraghdr)) & IP_OFFMASK) == 0) && 
+      ((ntohs(IPH_OFFSET(&ipr->iphdr)) & IP_OFFMASK) != 0)) {
+      /* ipr->iphdr is not the header from the first fragment, but fraghdr is
+       * -> copy fraghdr into ipr->iphdr since we want to have the header
+       * of the first fragment (for ICMP time exceeded and later, for copying
+       * all options, if supported)*/
+      SMEMCPY(&ipr->iphdr, fraghdr, IP_HLEN);
+    }
+  }
+  /* Track the current number of pbufs current 'in-flight', in order to limit 
+  the number of fragments that may be enqueued at any one time */
+  ip_reass_pbufcount += clen;
+
+  /* At this point, we have either created a new entry or pointing 
+   * to an existing one */
+
+  /* check for 'no more fragments', and update queue entry*/
+  if ((IPH_OFFSET(fraghdr) & PP_NTOHS(IP_MF)) == 0) {
+    ipr->flags |= IP_REASS_FLAG_LASTFRAG;
+    ipr->datagram_len = offset + len;
+    LWIP_DEBUGF(IP_REASS_DEBUG,
+     ("ip_reass: last fragment seen, total len %"S16_F"\n",
+      ipr->datagram_len));
+  }
+  /* find the right place to insert this pbuf */
+  /* @todo: trim pbufs if fragments are overlapping */
+  if (ip_reass_chain_frag_into_datagram_and_validate(ipr, p)) {
+    /* the totally last fragment (flag more fragments = 0) was received at least
+     * once AND all fragments are received */
+    ipr->datagram_len += IP_HLEN;
+
+    /* save the second pbuf before copying the header over the pointer */
+    r = ((struct ip_reass_helper*)ipr->p->payload)->next_pbuf;
+
+    /* copy the original ip header back to the first pbuf */
+    fraghdr = (struct ip_hdr*)(ipr->p->payload);
+    SMEMCPY(fraghdr, &ipr->iphdr, IP_HLEN);
+    IPH_LEN_SET(fraghdr, htons(ipr->datagram_len));
+    IPH_OFFSET_SET(fraghdr, 0);
+    IPH_CHKSUM_SET(fraghdr, 0);
+    /* @todo: do we need to set calculate the correct checksum? */
+    IPH_CHKSUM_SET(fraghdr, inet_chksum(fraghdr, IP_HLEN));
+
+    p = ipr->p;
+
+    /* chain together the pbufs contained within the reass_data list. */
+    while(r != NULL) {
+      iprh = (struct ip_reass_helper*)r->payload;
+
+      /* hide the ip header for every succeding fragment */
+      pbuf_header(r, -IP_HLEN);
+      pbuf_cat(p, r);
+      r = iprh->next_pbuf;
+    }
+    /* release the sources allocate for the fragment queue entry */
+    ip_reass_dequeue_datagram(ipr, ipr_prev);
+
+    /* and adjust the number of pbufs currently queued for reassembly. */
+    ip_reass_pbufcount -= pbuf_clen(p);
+
+    /* Return the pbuf chain */
+    return p;
+  }
+  /* the datagram is not (yet?) reassembled completely */
+  LWIP_DEBUGF(IP_REASS_DEBUG,("ip_reass_pbufcount: %d out\n", ip_reass_pbufcount));
+  return NULL;
+
+nullreturn:
+  LWIP_DEBUGF(IP_REASS_DEBUG,("ip_reass: nullreturn\n"));
+  IPFRAG_STATS_INC(ip_frag.drop);
+  pbuf_free(p);
+  return NULL;
+}
+#endif /* IP_REASSEMBLY */
+
+#if IP_FRAG
+#if IP_FRAG_USES_STATIC_BUF
+static u8_t buf[LWIP_MEM_ALIGN_SIZE(IP_FRAG_MAX_MTU + MEM_ALIGNMENT - 1)];
+#else /* IP_FRAG_USES_STATIC_BUF */
+
+#if !LWIP_NETIF_TX_SINGLE_PBUF
+/** Allocate a new struct pbuf_custom_ref */
+static struct pbuf_custom_ref*
+ip_frag_alloc_pbuf_custom_ref(void)
+{
+  return (struct pbuf_custom_ref*)memp_malloc(MEMP_FRAG_PBUF);
+}
+
+/** Free a struct pbuf_custom_ref */
+static void
+ip_frag_free_pbuf_custom_ref(struct pbuf_custom_ref* p)
+{
+  LWIP_ASSERT("p != NULL", p != NULL);
+  memp_free(MEMP_FRAG_PBUF, p);
+}
+
+/** Free-callback function to free a 'struct pbuf_custom_ref', called by
+ * pbuf_free. */
+static void
+ipfrag_free_pbuf_custom(struct pbuf *p)
+{
+  struct pbuf_custom_ref *pcr = (struct pbuf_custom_ref*)p;
+  LWIP_ASSERT("pcr != NULL", pcr != NULL);
+  LWIP_ASSERT("pcr == p", (void*)pcr == (void*)p);
+  if (pcr->original != NULL) {
+    pbuf_free(pcr->original);
+  }
+  ip_frag_free_pbuf_custom_ref(pcr);
+}
+#endif /* !LWIP_NETIF_TX_SINGLE_PBUF */
+#endif /* IP_FRAG_USES_STATIC_BUF */
+
+/**
+ * Fragment an IP datagram if too large for the netif.
+ *
+ * Chop the datagram in MTU sized chunks and send them in order
+ * by using a fixed size static memory buffer (PBUF_REF) or
+ * point PBUF_REFs into p (depending on IP_FRAG_USES_STATIC_BUF).
+ *
+ * @param p ip packet to send
+ * @param netif the netif on which to send
+ * @param dest destination ip address to which to send
+ *
+ * @return ERR_OK if sent successfully, err_t otherwise
+ */
+err_t 
+ip_frag(struct pbuf *p, struct netif *netif, ip_addr_t *dest)
+{
+  struct pbuf *rambuf;
+#if IP_FRAG_USES_STATIC_BUF
+  struct pbuf *header;
+#else
+#if !LWIP_NETIF_TX_SINGLE_PBUF
+  struct pbuf *newpbuf;
+#endif
+  struct ip_hdr *original_iphdr;
+#endif
+  struct ip_hdr *iphdr;
+  u16_t nfb;
+  u16_t left, cop;
+  u16_t mtu = netif->mtu;
+  u16_t ofo, omf;
+  u16_t last;
+  u16_t poff = IP_HLEN;
+  u16_t tmp;
+#if !IP_FRAG_USES_STATIC_BUF && !LWIP_NETIF_TX_SINGLE_PBUF
+  u16_t newpbuflen = 0;
+  u16_t left_to_copy;
+#endif
+
+  /* Get a RAM based MTU sized pbuf */
+#if IP_FRAG_USES_STATIC_BUF
+  /* When using a static buffer, we use a PBUF_REF, which we will
+   * use to reference the packet (without link header).
+   * Layer and length is irrelevant.
+   */
+  rambuf = pbuf_alloc(PBUF_LINK, 0, PBUF_REF);
+  if (rambuf == NULL) {
+    LWIP_DEBUGF(IP_REASS_DEBUG, ("ip_frag: pbuf_alloc(PBUF_LINK, 0, PBUF_REF) failed\n"));
+    return ERR_MEM;
+  }
+  rambuf->tot_len = rambuf->len = mtu;
+  rambuf->payload = LWIP_MEM_ALIGN((void *)buf);
+
+  /* Copy the IP header in it */
+  iphdr = (struct ip_hdr *)rambuf->payload;
+  SMEMCPY(iphdr, p->payload, IP_HLEN);
+#else /* IP_FRAG_USES_STATIC_BUF */
+  original_iphdr = (struct ip_hdr *)p->payload;
+  iphdr = original_iphdr;
+#endif /* IP_FRAG_USES_STATIC_BUF */
+
+  /* Save original offset */
+  tmp = ntohs(IPH_OFFSET(iphdr));
+  ofo = tmp & IP_OFFMASK;
+  omf = tmp & IP_MF;
+
+  left = p->tot_len - IP_HLEN;
+
+  nfb = (mtu - IP_HLEN) / 8;
+
+  while (left) {
+    last = (left <= mtu - IP_HLEN);
+
+    /* Set new offset and MF flag */
+    tmp = omf | (IP_OFFMASK & (ofo));
+    if (!last) {
+      tmp = tmp | IP_MF;
+    }
+
+    /* Fill this fragment */
+    cop = last ? left : nfb * 8;
+
+#if IP_FRAG_USES_STATIC_BUF
+    poff += pbuf_copy_partial(p, (u8_t*)iphdr + IP_HLEN, cop, poff);
+#else /* IP_FRAG_USES_STATIC_BUF */
+#if LWIP_NETIF_TX_SINGLE_PBUF
+    rambuf = pbuf_alloc(PBUF_IP, cop, PBUF_RAM);
+    if (rambuf == NULL) {
+      return ERR_MEM;
+    }
+    LWIP_ASSERT("this needs a pbuf in one piece!",
+      (rambuf->len == rambuf->tot_len) && (rambuf->next == NULL));
+    poff += pbuf_copy_partial(p, rambuf->payload, cop, poff);
+    /* make room for the IP header */
+    if(pbuf_header(rambuf, IP_HLEN)) {
+      pbuf_free(rambuf);
+      return ERR_MEM;
+    }
+    /* fill in the IP header */
+    SMEMCPY(rambuf->payload, original_iphdr, IP_HLEN);
+    iphdr = rambuf->payload;
+#else /* LWIP_NETIF_TX_SINGLE_PBUF */
+    /* When not using a static buffer, create a chain of pbufs.
+     * The first will be a PBUF_RAM holding the link and IP header.
+     * The rest will be PBUF_REFs mirroring the pbuf chain to be fragged,
+     * but limited to the size of an mtu.
+     */
+    rambuf = pbuf_alloc(PBUF_LINK, IP_HLEN, PBUF_RAM);
+    if (rambuf == NULL) {
+      return ERR_MEM;
+    }
+    LWIP_ASSERT("this needs a pbuf in one piece!",
+                (p->len >= (IP_HLEN)));
+    SMEMCPY(rambuf->payload, original_iphdr, IP_HLEN);
+    iphdr = (struct ip_hdr *)rambuf->payload;
+
+    /* Can just adjust p directly for needed offset. */
+    p->payload = (u8_t *)p->payload + poff;
+    p->len -= poff;
+
+    left_to_copy = cop;
+    while (left_to_copy) {
+      struct pbuf_custom_ref *pcr;
+      newpbuflen = (left_to_copy < p->len) ? left_to_copy : p->len;
+      /* Is this pbuf already empty? */
+      if (!newpbuflen) {
+        p = p->next;
+        continue;
+      }
+      pcr = ip_frag_alloc_pbuf_custom_ref();
+      if (pcr == NULL) {
+        pbuf_free(rambuf);
+        return ERR_MEM;
+      }
+      /* Mirror this pbuf, although we might not need all of it. */
+      newpbuf = pbuf_alloced_custom(PBUF_RAW, newpbuflen, PBUF_REF, &pcr->pc, p->payload, newpbuflen);
+      if (newpbuf == NULL) {
+        ip_frag_free_pbuf_custom_ref(pcr);
+        pbuf_free(rambuf);
+        return ERR_MEM;
+      }
+      pbuf_ref(p);
+      pcr->original = p;
+      pcr->pc.custom_free_function = ipfrag_free_pbuf_custom;
+
+      /* Add it to end of rambuf's chain, but using pbuf_cat, not pbuf_chain
+       * so that it is removed when pbuf_dechain is later called on rambuf.
+       */
+      pbuf_cat(rambuf, newpbuf);
+      left_to_copy -= newpbuflen;
+      if (left_to_copy) {
+        p = p->next;
+      }
+    }
+    poff = newpbuflen;
+#endif /* LWIP_NETIF_TX_SINGLE_PBUF */
+#endif /* IP_FRAG_USES_STATIC_BUF */
+
+    /* Correct header */
+    IPH_OFFSET_SET(iphdr, htons(tmp));
+    IPH_LEN_SET(iphdr, htons(cop + IP_HLEN));
+    IPH_CHKSUM_SET(iphdr, 0);
+    IPH_CHKSUM_SET(iphdr, inet_chksum(iphdr, IP_HLEN));
+
+#if IP_FRAG_USES_STATIC_BUF
+    if (last) {
+      pbuf_realloc(rambuf, left + IP_HLEN);
+    }
+
+    /* This part is ugly: we alloc a RAM based pbuf for 
+     * the link level header for each chunk and then 
+     * free it.A PBUF_ROM style pbuf for which pbuf_header
+     * worked would make things simpler.
+     */
+    header = pbuf_alloc(PBUF_LINK, 0, PBUF_RAM);
+    if (header != NULL) {
+      pbuf_chain(header, rambuf);
+      netif->output(netif, header, dest);
+      IPFRAG_STATS_INC(ip_frag.xmit);
+      snmp_inc_ipfragcreates();
+      pbuf_free(header);
+    } else {
+      LWIP_DEBUGF(IP_REASS_DEBUG, ("ip_frag: pbuf_alloc() for header failed\n"));
+      pbuf_free(rambuf);
+      return ERR_MEM;
+    }
+#else /* IP_FRAG_USES_STATIC_BUF */
+    /* No need for separate header pbuf - we allowed room for it in rambuf
+     * when allocated.
+     */
+    netif->output(netif, rambuf, dest);
+    IPFRAG_STATS_INC(ip_frag.xmit);
+
+    /* Unfortunately we can't reuse rambuf - the hardware may still be
+     * using the buffer. Instead we free it (and the ensuing chain) and
+     * recreate it next time round the loop. If we're lucky the hardware
+     * will have already sent the packet, the free will really free, and
+     * there will be zero memory penalty.
+     */
+    
+    pbuf_free(rambuf);
+#endif /* IP_FRAG_USES_STATIC_BUF */
+    left -= cop;
+    ofo += nfb;
+  }
+#if IP_FRAG_USES_STATIC_BUF
+  pbuf_free(rambuf);
+#endif /* IP_FRAG_USES_STATIC_BUF */
+  snmp_inc_ipfragoks();
+  return ERR_OK;
+}
+#endif /* IP_FRAG */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/core/mem.c	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,643 @@
+#pragma diag_remark 177
+/**
+ * @file
+ * Dynamic memory manager
+ *
+ * This is a lightweight replacement for the standard C library malloc().
+ *
+ * If you want to use the standard C library malloc() instead, define
+ * MEM_LIBC_MALLOC to 1 in your lwipopts.h
+ *
+ * To let mem_malloc() use pools (prevents fragmentation and is much faster than
+ * a heap but might waste some memory), define MEM_USE_POOLS to 1, define
+ * MEM_USE_CUSTOM_POOLS to 1 and create a file "lwippools.h" that includes a list
+ * of pools like this (more pools can be added between _START and _END):
+ *
+ * Define three pools with sizes 256, 512, and 1512 bytes
+ * LWIP_MALLOC_MEMPOOL_START
+ * LWIP_MALLOC_MEMPOOL(20, 256)
+ * LWIP_MALLOC_MEMPOOL(10, 512)
+ * LWIP_MALLOC_MEMPOOL(5, 1512)
+ * LWIP_MALLOC_MEMPOOL_END
+ */
+
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ *
+ * Author: Adam Dunkels <adam@sics.se>
+ *         Simon Goldschmidt
+ *
+ */
+
+#include "lwip/opt.h"
+
+#if !MEM_LIBC_MALLOC /* don't build if not configured for use in lwipopts.h */
+
+#include "lwip/def.h"
+#include "lwip/mem.h"
+#include "lwip/sys.h"
+#include "lwip/stats.h"
+#include "lwip/err.h"
+
+#include <string.h>
+
+#if MEM_USE_POOLS
+/* lwIP head implemented with different sized pools */
+
+/**
+ * Allocate memory: determine the smallest pool that is big enough
+ * to contain an element of 'size' and get an element from that pool.
+ *
+ * @param size the size in bytes of the memory needed
+ * @return a pointer to the allocated memory or NULL if the pool is empty
+ */
+void *
+mem_malloc(mem_size_t size)
+{
+  struct memp_malloc_helper *element;
+  memp_t poolnr;
+  mem_size_t required_size = size + sizeof(struct memp_malloc_helper);
+
+  for (poolnr = MEMP_POOL_FIRST; poolnr <= MEMP_POOL_LAST; poolnr = (memp_t)(poolnr + 1)) {
+#if MEM_USE_POOLS_TRY_BIGGER_POOL
+again:
+#endif /* MEM_USE_POOLS_TRY_BIGGER_POOL */
+    /* is this pool big enough to hold an element of the required size
+       plus a struct memp_malloc_helper that saves the pool this element came from? */
+    if (required_size <= memp_sizes[poolnr]) {
+      break;
+    }
+  }
+  if (poolnr > MEMP_POOL_LAST) {
+    LWIP_ASSERT("mem_malloc(): no pool is that big!", 0);
+    return NULL;
+  }
+  element = (struct memp_malloc_helper*)memp_malloc(poolnr);
+  if (element == NULL) {
+    /* No need to DEBUGF or ASSERT: This error is already
+       taken care of in memp.c */
+#if MEM_USE_POOLS_TRY_BIGGER_POOL
+    /** Try a bigger pool if this one is empty! */
+    if (poolnr < MEMP_POOL_LAST) {
+      poolnr++;
+      goto again;
+    }
+#endif /* MEM_USE_POOLS_TRY_BIGGER_POOL */
+    return NULL;
+  }
+
+  /* save the pool number this element came from */
+  element->poolnr = poolnr;
+  /* and return a pointer to the memory directly after the struct memp_malloc_helper */
+  element++;
+
+  return element;
+}
+
+/**
+ * Free memory previously allocated by mem_malloc. Loads the pool number
+ * and calls memp_free with that pool number to put the element back into
+ * its pool
+ *
+ * @param rmem the memory element to free
+ */
+void
+mem_free(void *rmem)
+{
+  struct memp_malloc_helper *hmem = (struct memp_malloc_helper*)rmem;
+
+  LWIP_ASSERT("rmem != NULL", (rmem != NULL));
+  LWIP_ASSERT("rmem == MEM_ALIGN(rmem)", (rmem == LWIP_MEM_ALIGN(rmem)));
+
+  /* get the original struct memp_malloc_helper */
+  hmem--;
+
+  LWIP_ASSERT("hmem != NULL", (hmem != NULL));
+  LWIP_ASSERT("hmem == MEM_ALIGN(hmem)", (hmem == LWIP_MEM_ALIGN(hmem)));
+  LWIP_ASSERT("hmem->poolnr < MEMP_MAX", (hmem->poolnr < MEMP_MAX));
+
+  /* and put it in the pool we saved earlier */
+  memp_free(hmem->poolnr, hmem);
+}
+
+#else /* MEM_USE_POOLS */
+/* lwIP replacement for your libc malloc() */
+
+/**
+ * The heap is made up as a list of structs of this type.
+ * This does not have to be aligned since for getting its size,
+ * we only use the macro SIZEOF_STRUCT_MEM, which automatically alignes.
+ */
+struct mem {
+  /** index (-> ram[next]) of the next struct */
+  mem_size_t next;
+  /** index (-> ram[prev]) of the previous struct */
+  mem_size_t prev;
+  /** 1: this area is used; 0: this area is unused */
+  u8_t used;
+};
+
+/** All allocated blocks will be MIN_SIZE bytes big, at least!
+ * MIN_SIZE can be overridden to suit your needs. Smaller values save space,
+ * larger values could prevent too small blocks to fragment the RAM too much. */
+#ifndef MIN_SIZE
+#define MIN_SIZE             12
+#endif /* MIN_SIZE */
+/* some alignment macros: we define them here for better source code layout */
+#define MIN_SIZE_ALIGNED     LWIP_MEM_ALIGN_SIZE(MIN_SIZE)
+#define SIZEOF_STRUCT_MEM    LWIP_MEM_ALIGN_SIZE(sizeof(struct mem))
+#define MEM_SIZE_ALIGNED     LWIP_MEM_ALIGN_SIZE(MEM_SIZE)
+
+/** If you want to relocate the heap to external memory, simply define
+ * LWIP_RAM_HEAP_POINTER as a void-pointer to that location.
+ * If so, make sure the memory at that location is big enough (see below on
+ * how that space is calculated). */
+#ifndef LWIP_RAM_HEAP_POINTER
+/** the heap. we need one struct mem at the end and some room for alignment */
+u8_t ram_heap[MEM_SIZE_ALIGNED + (2*SIZEOF_STRUCT_MEM) + MEM_ALIGNMENT] MEM_POSITION;
+#define LWIP_RAM_HEAP_POINTER ram_heap
+#endif /* LWIP_RAM_HEAP_POINTER */
+
+/** pointer to the heap (ram_heap): for alignment, ram is now a pointer instead of an array */
+static u8_t *ram;
+/** the last entry, always unused! */
+static struct mem *ram_end;
+/** pointer to the lowest free block, this is used for faster search */
+static struct mem *lfree;
+
+/** concurrent access protection */
+static sys_mutex_t mem_mutex;
+
+#if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
+
+static volatile u8_t mem_free_count;
+
+/* Allow mem_free from other (e.g. interrupt) context */
+#define LWIP_MEM_FREE_DECL_PROTECT()  SYS_ARCH_DECL_PROTECT(lev_free)
+#define LWIP_MEM_FREE_PROTECT()       SYS_ARCH_PROTECT(lev_free)
+#define LWIP_MEM_FREE_UNPROTECT()     SYS_ARCH_UNPROTECT(lev_free)
+#define LWIP_MEM_ALLOC_DECL_PROTECT() SYS_ARCH_DECL_PROTECT(lev_alloc)
+#define LWIP_MEM_ALLOC_PROTECT()      SYS_ARCH_PROTECT(lev_alloc)
+#define LWIP_MEM_ALLOC_UNPROTECT()    SYS_ARCH_UNPROTECT(lev_alloc)
+
+#else /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
+
+/* Protect the heap only by using a semaphore */
+#define LWIP_MEM_FREE_DECL_PROTECT()
+#define LWIP_MEM_FREE_PROTECT()    sys_mutex_lock(&mem_mutex)
+#define LWIP_MEM_FREE_UNPROTECT()  sys_mutex_unlock(&mem_mutex)
+/* mem_malloc is protected using semaphore AND LWIP_MEM_ALLOC_PROTECT */
+#define LWIP_MEM_ALLOC_DECL_PROTECT()
+#define LWIP_MEM_ALLOC_PROTECT()
+#define LWIP_MEM_ALLOC_UNPROTECT()
+
+#endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
+
+
+/**
+ * "Plug holes" by combining adjacent empty struct mems.
+ * After this function is through, there should not exist
+ * one empty struct mem pointing to another empty struct mem.
+ *
+ * @param mem this points to a struct mem which just has been freed
+ * @internal this function is only called by mem_free() and mem_trim()
+ *
+ * This assumes access to the heap is protected by the calling function
+ * already.
+ */
+static void
+plug_holes(struct mem *mem)
+{
+  struct mem *nmem;
+  struct mem *pmem;
+
+  LWIP_ASSERT("plug_holes: mem >= ram", (u8_t *)mem >= ram);
+  LWIP_ASSERT("plug_holes: mem < ram_end", (u8_t *)mem < (u8_t *)ram_end);
+  LWIP_ASSERT("plug_holes: mem->used == 0", mem->used == 0);
+
+  /* plug hole forward */
+  LWIP_ASSERT("plug_holes: mem->next <= MEM_SIZE_ALIGNED", mem->next <= MEM_SIZE_ALIGNED);
+
+  nmem = (struct mem *)(void *)&ram[mem->next];
+  if (mem != nmem && nmem->used == 0 && (u8_t *)nmem != (u8_t *)ram_end) {
+    /* if mem->next is unused and not end of ram, combine mem and mem->next */
+    if (lfree == nmem) {
+      lfree = mem;
+    }
+    mem->next = nmem->next;
+    ((struct mem *)(void *)&ram[nmem->next])->prev = (mem_size_t)((u8_t *)mem - ram);
+  }
+
+  /* plug hole backward */
+  pmem = (struct mem *)(void *)&ram[mem->prev];
+  if (pmem != mem && pmem->used == 0) {
+    /* if mem->prev is unused, combine mem and mem->prev */
+    if (lfree == mem) {
+      lfree = pmem;
+    }
+    pmem->next = mem->next;
+    ((struct mem *)(void *)&ram[mem->next])->prev = (mem_size_t)((u8_t *)pmem - ram);
+  }
+}
+
+/**
+ * Zero the heap and initialize start, end and lowest-free
+ */
+void
+mem_init(void)
+{
+  struct mem *mem;
+
+  LWIP_ASSERT("Sanity check alignment",
+    (SIZEOF_STRUCT_MEM & (MEM_ALIGNMENT-1)) == 0);
+
+  /* align the heap */
+  ram = (u8_t *)LWIP_MEM_ALIGN(LWIP_RAM_HEAP_POINTER);
+  /* initialize the start of the heap */
+  mem = (struct mem *)(void *)ram;
+  mem->next = MEM_SIZE_ALIGNED;
+  mem->prev = 0;
+  mem->used = 0;
+  /* initialize the end of the heap */
+  ram_end = (struct mem *)(void *)&ram[MEM_SIZE_ALIGNED];
+  ram_end->used = 1;
+  ram_end->next = MEM_SIZE_ALIGNED;
+  ram_end->prev = MEM_SIZE_ALIGNED;
+
+  /* initialize the lowest-free pointer to the start of the heap */
+  lfree = (struct mem *)(void *)ram;
+
+  MEM_STATS_AVAIL(avail, MEM_SIZE_ALIGNED);
+
+  if(sys_mutex_new(&mem_mutex) != ERR_OK) {
+    LWIP_ASSERT("failed to create mem_mutex", 0);
+  }
+}
+
+/**
+ * Put a struct mem back on the heap
+ *
+ * @param rmem is the data portion of a struct mem as returned by a previous
+ *             call to mem_malloc()
+ */
+void
+mem_free(void *rmem)
+{
+  struct mem *mem;
+  LWIP_MEM_FREE_DECL_PROTECT();
+
+  if (rmem == NULL) {
+    LWIP_DEBUGF(MEM_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_SERIOUS, ("mem_free(p == NULL) was called.\n"));
+    return;
+  }
+  LWIP_ASSERT("mem_free: sanity check alignment", (((mem_ptr_t)rmem) & (MEM_ALIGNMENT-1)) == 0);
+
+  LWIP_ASSERT("mem_free: legal memory", (u8_t *)rmem >= (u8_t *)ram &&
+    (u8_t *)rmem < (u8_t *)ram_end);
+
+  if ((u8_t *)rmem < (u8_t *)ram || (u8_t *)rmem >= (u8_t *)ram_end) {
+    SYS_ARCH_DECL_PROTECT(lev);
+    LWIP_DEBUGF(MEM_DEBUG | LWIP_DBG_LEVEL_SEVERE, ("mem_free: illegal memory\n"));
+    /* protect mem stats from concurrent access */
+    SYS_ARCH_PROTECT(lev);
+    MEM_STATS_INC(illegal);
+    SYS_ARCH_UNPROTECT(lev);
+    return;
+  }
+  /* protect the heap from concurrent access */
+  LWIP_MEM_FREE_PROTECT();
+  /* Get the corresponding struct mem ... */
+  mem = (struct mem *)(void *)((u8_t *)rmem - SIZEOF_STRUCT_MEM);
+  /* ... which has to be in a used state ... */
+  LWIP_ASSERT("mem_free: mem->used", mem->used);
+  /* ... and is now unused. */
+  mem->used = 0;
+
+  if (mem < lfree) {
+    /* the newly freed struct is now the lowest */
+    lfree = mem;
+  }
+
+  MEM_STATS_DEC_USED(used, mem->next - (mem_size_t)(((u8_t *)mem - ram)));
+
+  /* finally, see if prev or next are free also */
+  plug_holes(mem);
+#if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
+  mem_free_count = 1;
+#endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
+  LWIP_MEM_FREE_UNPROTECT();
+}
+
+/**
+ * Shrink memory returned by mem_malloc().
+ *
+ * @param rmem pointer to memory allocated by mem_malloc the is to be shrinked
+ * @param newsize required size after shrinking (needs to be smaller than or
+ *                equal to the previous size)
+ * @return for compatibility reasons: is always == rmem, at the moment
+ *         or NULL if newsize is > old size, in which case rmem is NOT touched
+ *         or freed!
+ */
+void *
+mem_trim(void *rmem, mem_size_t newsize)
+{
+  mem_size_t size;
+  mem_size_t ptr, ptr2;
+  struct mem *mem, *mem2;
+  /* use the FREE_PROTECT here: it protects with sem OR SYS_ARCH_PROTECT */
+  LWIP_MEM_FREE_DECL_PROTECT();
+
+  /* Expand the size of the allocated memory region so that we can
+     adjust for alignment. */
+  newsize = LWIP_MEM_ALIGN_SIZE(newsize);
+
+  if(newsize < MIN_SIZE_ALIGNED) {
+    /* every data block must be at least MIN_SIZE_ALIGNED long */
+    newsize = MIN_SIZE_ALIGNED;
+  }
+
+  if (newsize > MEM_SIZE_ALIGNED) {
+    return NULL;
+  }
+
+  LWIP_ASSERT("mem_trim: legal memory", (u8_t *)rmem >= (u8_t *)ram &&
+   (u8_t *)rmem < (u8_t *)ram_end);
+
+  if ((u8_t *)rmem < (u8_t *)ram || (u8_t *)rmem >= (u8_t *)ram_end) {
+    SYS_ARCH_DECL_PROTECT(lev);
+    LWIP_DEBUGF(MEM_DEBUG | LWIP_DBG_LEVEL_SEVERE, ("mem_trim: illegal memory\n"));
+    /* protect mem stats from concurrent access */
+    SYS_ARCH_PROTECT(lev);
+    MEM_STATS_INC(illegal);
+    SYS_ARCH_UNPROTECT(lev);
+    return rmem;
+  }
+  /* Get the corresponding struct mem ... */
+  mem = (struct mem *)(void *)((u8_t *)rmem - SIZEOF_STRUCT_MEM);
+  /* ... and its offset pointer */
+  ptr = (mem_size_t)((u8_t *)mem - ram);
+
+  size = mem->next - ptr - SIZEOF_STRUCT_MEM;
+  LWIP_ASSERT("mem_trim can only shrink memory", newsize <= size);
+  if (newsize > size) {
+    /* not supported */
+    return NULL;
+  }
+  if (newsize == size) {
+    /* No change in size, simply return */
+    return rmem;
+  }
+
+  /* protect the heap from concurrent access */
+  LWIP_MEM_FREE_PROTECT();
+
+  mem2 = (struct mem *)(void *)&ram[mem->next];
+  if(mem2->used == 0) {
+    /* The next struct is unused, we can simply move it at little */
+    mem_size_t next;
+    /* remember the old next pointer */
+    next = mem2->next;
+    /* create new struct mem which is moved directly after the shrinked mem */
+    ptr2 = ptr + SIZEOF_STRUCT_MEM + newsize;
+    if (lfree == mem2) {
+      lfree = (struct mem *)(void *)&ram[ptr2];
+    }
+    mem2 = (struct mem *)(void *)&ram[ptr2];
+    mem2->used = 0;
+    /* restore the next pointer */
+    mem2->next = next;
+    /* link it back to mem */
+    mem2->prev = ptr;
+    /* link mem to it */
+    mem->next = ptr2;
+    /* last thing to restore linked list: as we have moved mem2,
+     * let 'mem2->next->prev' point to mem2 again. but only if mem2->next is not
+     * the end of the heap */
+    if (mem2->next != MEM_SIZE_ALIGNED) {
+      ((struct mem *)(void *)&ram[mem2->next])->prev = ptr2;
+    }
+    MEM_STATS_DEC_USED(used, (size - newsize));
+    /* no need to plug holes, we've already done that */
+  } else if (newsize + SIZEOF_STRUCT_MEM + MIN_SIZE_ALIGNED <= size) {
+    /* Next struct is used but there's room for another struct mem with
+     * at least MIN_SIZE_ALIGNED of data.
+     * Old size ('size') must be big enough to contain at least 'newsize' plus a struct mem
+     * ('SIZEOF_STRUCT_MEM') with some data ('MIN_SIZE_ALIGNED').
+     * @todo we could leave out MIN_SIZE_ALIGNED. We would create an empty
+     *       region that couldn't hold data, but when mem->next gets freed,
+     *       the 2 regions would be combined, resulting in more free memory */
+    ptr2 = ptr + SIZEOF_STRUCT_MEM + newsize;
+    mem2 = (struct mem *)(void *)&ram[ptr2];
+    if (mem2 < lfree) {
+      lfree = mem2;
+    }
+    mem2->used = 0;
+    mem2->next = mem->next;
+    mem2->prev = ptr;
+    mem->next = ptr2;
+    if (mem2->next != MEM_SIZE_ALIGNED) {
+      ((struct mem *)(void *)&ram[mem2->next])->prev = ptr2;
+    }
+    MEM_STATS_DEC_USED(used, (size - newsize));
+    /* the original mem->next is used, so no need to plug holes! */
+  }
+  /* else {
+    next struct mem is used but size between mem and mem2 is not big enough
+    to create another struct mem
+    -> don't do anyhting. 
+    -> the remaining space stays unused since it is too small
+  } */
+#if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
+  mem_free_count = 1;
+#endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
+  LWIP_MEM_FREE_UNPROTECT();
+  return rmem;
+}
+
+/**
+ * Adam's mem_malloc() plus solution for bug #17922
+ * Allocate a block of memory with a minimum of 'size' bytes.
+ *
+ * @param size is the minimum size of the requested block in bytes.
+ * @return pointer to allocated memory or NULL if no free memory was found.
+ *
+ * Note that the returned value will always be aligned (as defined by MEM_ALIGNMENT).
+ */
+void *
+mem_malloc(mem_size_t size)
+{
+  mem_size_t ptr, ptr2;
+  struct mem *mem, *mem2;
+#if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
+  u8_t local_mem_free_count = 0;
+#endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
+  LWIP_MEM_ALLOC_DECL_PROTECT();
+
+  if (size == 0) {
+    return NULL;
+  }
+
+  /* Expand the size of the allocated memory region so that we can
+     adjust for alignment. */
+  size = LWIP_MEM_ALIGN_SIZE(size);
+
+  if(size < MIN_SIZE_ALIGNED) {
+    /* every data block must be at least MIN_SIZE_ALIGNED long */
+    size = MIN_SIZE_ALIGNED;
+  }
+
+  if (size > MEM_SIZE_ALIGNED) {
+    return NULL;
+  }
+
+  /* protect the heap from concurrent access */
+  sys_mutex_lock(&mem_mutex);
+  LWIP_MEM_ALLOC_PROTECT();
+#if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
+  /* run as long as a mem_free disturbed mem_malloc */
+  do {
+    local_mem_free_count = 0;
+#endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
+
+    /* Scan through the heap searching for a free block that is big enough,
+     * beginning with the lowest free block.
+     */
+    for (ptr = (mem_size_t)((u8_t *)lfree - ram); ptr < MEM_SIZE_ALIGNED - size;
+         ptr = ((struct mem *)(void *)&ram[ptr])->next) {
+      mem = (struct mem *)(void *)&ram[ptr];
+#if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
+      mem_free_count = 0;
+      LWIP_MEM_ALLOC_UNPROTECT();
+      /* allow mem_free to run */
+      LWIP_MEM_ALLOC_PROTECT();
+      if (mem_free_count != 0) {
+        local_mem_free_count = mem_free_count;
+      }
+      mem_free_count = 0;
+#endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
+
+      if ((!mem->used) &&
+          (mem->next - (ptr + SIZEOF_STRUCT_MEM)) >= size) {
+        /* mem is not used and at least perfect fit is possible:
+         * mem->next - (ptr + SIZEOF_STRUCT_MEM) gives us the 'user data size' of mem */
+
+        if (mem->next - (ptr + SIZEOF_STRUCT_MEM) >= (size + SIZEOF_STRUCT_MEM + MIN_SIZE_ALIGNED)) {
+          /* (in addition to the above, we test if another struct mem (SIZEOF_STRUCT_MEM) containing
+           * at least MIN_SIZE_ALIGNED of data also fits in the 'user data space' of 'mem')
+           * -> split large block, create empty remainder,
+           * remainder must be large enough to contain MIN_SIZE_ALIGNED data: if
+           * mem->next - (ptr + (2*SIZEOF_STRUCT_MEM)) == size,
+           * struct mem would fit in but no data between mem2 and mem2->next
+           * @todo we could leave out MIN_SIZE_ALIGNED. We would create an empty
+           *       region that couldn't hold data, but when mem->next gets freed,
+           *       the 2 regions would be combined, resulting in more free memory
+           */
+          ptr2 = ptr + SIZEOF_STRUCT_MEM + size;
+          /* create mem2 struct */
+          mem2 = (struct mem *)(void *)&ram[ptr2];
+          mem2->used = 0;
+          mem2->next = mem->next;
+          mem2->prev = ptr;
+          /* and insert it between mem and mem->next */
+          mem->next = ptr2;
+          mem->used = 1;
+
+          if (mem2->next != MEM_SIZE_ALIGNED) {
+            ((struct mem *)(void *)&ram[mem2->next])->prev = ptr2;
+          }
+          MEM_STATS_INC_USED(used, (size + SIZEOF_STRUCT_MEM));
+        } else {
+          /* (a mem2 struct does no fit into the user data space of mem and mem->next will always
+           * be used at this point: if not we have 2 unused structs in a row, plug_holes should have
+           * take care of this).
+           * -> near fit or excact fit: do not split, no mem2 creation
+           * also can't move mem->next directly behind mem, since mem->next
+           * will always be used at this point!
+           */
+          mem->used = 1;
+          MEM_STATS_INC_USED(used, mem->next - (mem_size_t)((u8_t *)mem - ram));
+        }
+
+        if (mem == lfree) {
+          /* Find next free block after mem and update lowest free pointer */
+          while (lfree->used && lfree != ram_end) {
+            LWIP_MEM_ALLOC_UNPROTECT();
+            /* prevent high interrupt latency... */
+            LWIP_MEM_ALLOC_PROTECT();
+            lfree = (struct mem *)(void *)&ram[lfree->next];
+          }
+          LWIP_ASSERT("mem_malloc: !lfree->used", ((lfree == ram_end) || (!lfree->used)));
+        }
+        LWIP_MEM_ALLOC_UNPROTECT();
+        sys_mutex_unlock(&mem_mutex);
+        LWIP_ASSERT("mem_malloc: allocated memory not above ram_end.",
+         (mem_ptr_t)mem + SIZEOF_STRUCT_MEM + size <= (mem_ptr_t)ram_end);
+        LWIP_ASSERT("mem_malloc: allocated memory properly aligned.",
+         ((mem_ptr_t)mem + SIZEOF_STRUCT_MEM) % MEM_ALIGNMENT == 0);
+        LWIP_ASSERT("mem_malloc: sanity check alignment",
+          (((mem_ptr_t)mem) & (MEM_ALIGNMENT-1)) == 0);
+
+        return (u8_t *)mem + SIZEOF_STRUCT_MEM;
+      }
+    }
+#if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
+    /* if we got interrupted by a mem_free, try again */
+  } while(local_mem_free_count != 0);
+#endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
+  LWIP_DEBUGF(MEM_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("mem_malloc: could not allocate %"S16_F" bytes\n", (s16_t)size));
+  MEM_STATS_INC(err);
+  LWIP_MEM_ALLOC_UNPROTECT();
+  sys_mutex_unlock(&mem_mutex);
+  return NULL;
+}
+
+#endif /* MEM_USE_POOLS */
+/**
+ * Contiguously allocates enough space for count objects that are size bytes
+ * of memory each and returns a pointer to the allocated memory.
+ *
+ * The allocated memory is filled with bytes of value zero.
+ *
+ * @param count number of objects to allocate
+ * @param size size of the objects to allocate
+ * @return pointer to allocated memory / NULL pointer if there is an error
+ */
+void *mem_calloc(mem_size_t count, mem_size_t size)
+{
+  void *p;
+
+  /* allocate 'count' objects of size 'size' */
+  p = mem_malloc(count * size);
+  if (p) {
+    /* zero the memory */
+    memset(p, 0, count * size);
+  }
+  return p;
+}
+
+#endif /* !MEM_LIBC_MALLOC */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/core/memp.c	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,469 @@
+/**
+ * @file
+ * Dynamic pool memory manager
+ *
+ * lwIP has dedicated pools for many structures (netconn, protocol control blocks,
+ * packet buffers, ...). All these pools are managed here.
+ */
+
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+
+#include "lwip/opt.h"
+
+#include "lwip/memp.h"
+#include "lwip/pbuf.h"
+#include "lwip/udp.h"
+#include "lwip/raw.h"
+#include "lwip/tcp_impl.h"
+#include "lwip/igmp.h"
+#include "lwip/api.h"
+#include "lwip/api_msg.h"
+#include "lwip/tcpip.h"
+#include "lwip/sys.h"
+#include "lwip/timers.h"
+#include "lwip/stats.h"
+#include "netif/etharp.h"
+#include "lwip/ip_frag.h"
+#include "lwip/snmp_structs.h"
+#include "lwip/snmp_msg.h"
+#include "lwip/dns.h"
+#include "netif/ppp_oe.h"
+
+#include <string.h>
+
+#if !MEMP_MEM_MALLOC /* don't build if not configured for use in lwipopts.h */
+
+struct memp {
+  struct memp *next;
+#if MEMP_OVERFLOW_CHECK
+  const char *file;
+  int line;
+#endif /* MEMP_OVERFLOW_CHECK */
+};
+
+#if MEMP_OVERFLOW_CHECK
+/* if MEMP_OVERFLOW_CHECK is turned on, we reserve some bytes at the beginning
+ * and at the end of each element, initialize them as 0xcd and check
+ * them later. */
+/* If MEMP_OVERFLOW_CHECK is >= 2, on every call to memp_malloc or memp_free,
+ * every single element in each pool is checked!
+ * This is VERY SLOW but also very helpful. */
+/* MEMP_SANITY_REGION_BEFORE and MEMP_SANITY_REGION_AFTER can be overridden in
+ * lwipopts.h to change the amount reserved for checking. */
+#ifndef MEMP_SANITY_REGION_BEFORE
+#define MEMP_SANITY_REGION_BEFORE  16
+#endif /* MEMP_SANITY_REGION_BEFORE*/
+#if MEMP_SANITY_REGION_BEFORE > 0
+#define MEMP_SANITY_REGION_BEFORE_ALIGNED    LWIP_MEM_ALIGN_SIZE(MEMP_SANITY_REGION_BEFORE)
+#else
+#define MEMP_SANITY_REGION_BEFORE_ALIGNED    0
+#endif /* MEMP_SANITY_REGION_BEFORE*/
+#ifndef MEMP_SANITY_REGION_AFTER
+#define MEMP_SANITY_REGION_AFTER   16
+#endif /* MEMP_SANITY_REGION_AFTER*/
+#if MEMP_SANITY_REGION_AFTER > 0
+#define MEMP_SANITY_REGION_AFTER_ALIGNED     LWIP_MEM_ALIGN_SIZE(MEMP_SANITY_REGION_AFTER)
+#else
+#define MEMP_SANITY_REGION_AFTER_ALIGNED     0
+#endif /* MEMP_SANITY_REGION_AFTER*/
+
+/* MEMP_SIZE: save space for struct memp and for sanity check */
+#define MEMP_SIZE          (LWIP_MEM_ALIGN_SIZE(sizeof(struct memp)) + MEMP_SANITY_REGION_BEFORE_ALIGNED)
+#define MEMP_ALIGN_SIZE(x) (LWIP_MEM_ALIGN_SIZE(x) + MEMP_SANITY_REGION_AFTER_ALIGNED)
+
+#else /* MEMP_OVERFLOW_CHECK */
+
+/* No sanity checks
+ * We don't need to preserve the struct memp while not allocated, so we
+ * can save a little space and set MEMP_SIZE to 0.
+ */
+#define MEMP_SIZE           0
+#define MEMP_ALIGN_SIZE(x) (LWIP_MEM_ALIGN_SIZE(x))
+
+#endif /* MEMP_OVERFLOW_CHECK */
+
+/** This array holds the first free element of each pool.
+ *  Elements form a linked list. */
+static struct memp *memp_tab[MEMP_MAX] MEM_POSITION;
+
+#else /* MEMP_MEM_MALLOC */
+
+#define MEMP_ALIGN_SIZE(x) (LWIP_MEM_ALIGN_SIZE(x))
+
+#endif /* MEMP_MEM_MALLOC */
+
+/** This array holds the element sizes of each pool. */
+#if !MEM_USE_POOLS && !MEMP_MEM_MALLOC
+static
+#endif
+const u16_t memp_sizes[MEMP_MAX] = {
+#define LWIP_MEMPOOL(name,num,size,desc)  LWIP_MEM_ALIGN_SIZE(size),
+#include "lwip/memp_std.h"
+};
+
+#if !MEMP_MEM_MALLOC /* don't build if not configured for use in lwipopts.h */
+
+/** This array holds the number of elements in each pool. */
+static const u16_t memp_num[MEMP_MAX] = {
+#define LWIP_MEMPOOL(name,num,size,desc)  (num),
+#include "lwip/memp_std.h"
+};
+
+/** This array holds a textual description of each pool. */
+#ifdef LWIP_DEBUG
+static const char *memp_desc[MEMP_MAX] = {
+#define LWIP_MEMPOOL(name,num,size,desc)  (desc),
+#include "lwip/memp_std.h"
+};
+#endif /* LWIP_DEBUG */
+
+#if MEMP_SEPARATE_POOLS
+
+/** This creates each memory pool. These are named memp_memory_XXX_base (where
+ * XXX is the name of the pool defined in memp_std.h).
+ * To relocate a pool, declare it as extern in cc.h. Example for GCC:
+ *   extern u8_t __attribute__((section(".onchip_mem"))) memp_memory_UDP_PCB_base[];
+ */
+#define LWIP_MEMPOOL(name,num,size,desc) u8_t memp_memory_ ## name ## _base \
+  [((num) * (MEMP_SIZE + MEMP_ALIGN_SIZE(size)))];   
+#include "lwip/memp_std.h"
+
+/** This array holds the base of each memory pool. */
+static u8_t *const memp_bases[] = { 
+#define LWIP_MEMPOOL(name,num,size,desc) memp_memory_ ## name ## _base,   
+#include "lwip/memp_std.h"
+} MEM_POSITION;
+
+#else /* MEMP_SEPARATE_POOLS */
+
+/** This is the actual memory used by the pools (all pools in one big block). */
+static u8_t memp_memory[MEM_ALIGNMENT - 1 
+#define LWIP_MEMPOOL(name,num,size,desc) + ( (num) * (MEMP_SIZE + MEMP_ALIGN_SIZE(size) ) )
+#include "lwip/memp_std.h"
+] MEM_POSITION;
+
+#endif /* MEMP_SEPARATE_POOLS */
+
+#if MEMP_SANITY_CHECK
+/**
+ * Check that memp-lists don't form a circle
+ */
+static int
+memp_sanity(void)
+{
+  s16_t i, c;
+  struct memp *m, *n;
+
+  for (i = 0; i < MEMP_MAX; i++) {
+    for (m = memp_tab[i]; m != NULL; m = m->next) {
+      c = 1;
+      for (n = memp_tab[i]; n != NULL; n = n->next) {
+        if (n == m && --c < 0) {
+          return 0;
+        }
+      }
+    }
+  }
+  return 1;
+}
+#endif /* MEMP_SANITY_CHECK*/
+#if MEMP_OVERFLOW_CHECK
+#if defined(LWIP_DEBUG) && MEMP_STATS
+static const char * memp_overflow_names[] = {
+#define LWIP_MEMPOOL(name,num,size,desc) "/"desc,
+#include "lwip/memp_std.h"
+  };
+#endif
+
+/**
+ * Check if a memp element was victim of an overflow
+ * (e.g. the restricted area after it has been altered)
+ *
+ * @param p the memp element to check
+ * @param memp_type the pool p comes from
+ */
+static void
+memp_overflow_check_element_overflow(struct memp *p, u16_t memp_type)
+{
+  u16_t k;
+  u8_t *m;
+#if MEMP_SANITY_REGION_AFTER_ALIGNED > 0
+  m = (u8_t*)p + MEMP_SIZE + memp_sizes[memp_type];
+  for (k = 0; k < MEMP_SANITY_REGION_AFTER_ALIGNED; k++) {
+    if (m[k] != 0xcd) {
+      char errstr[128] = "detected memp overflow in pool ";
+      char digit[] = "0";
+      if(memp_type >= 10) {
+        digit[0] = '0' + (memp_type/10);
+        strcat(errstr, digit);
+      }
+      digit[0] = '0' + (memp_type%10);
+      strcat(errstr, digit);
+#if defined(LWIP_DEBUG) && MEMP_STATS
+      strcat(errstr, memp_overflow_names[memp_type]);
+#endif
+      LWIP_ASSERT(errstr, 0);
+    }
+  }
+#endif
+}
+
+/**
+ * Check if a memp element was victim of an underflow
+ * (e.g. the restricted area before it has been altered)
+ *
+ * @param p the memp element to check
+ * @param memp_type the pool p comes from
+ */
+static void
+memp_overflow_check_element_underflow(struct memp *p, u16_t memp_type)
+{
+  u16_t k;
+  u8_t *m;
+#if MEMP_SANITY_REGION_BEFORE_ALIGNED > 0
+  m = (u8_t*)p + MEMP_SIZE - MEMP_SANITY_REGION_BEFORE_ALIGNED;
+  for (k = 0; k < MEMP_SANITY_REGION_BEFORE_ALIGNED; k++) {
+    if (m[k] != 0xcd) {
+      char errstr[128] = "detected memp underflow in pool ";
+      char digit[] = "0";
+      if(memp_type >= 10) {
+        digit[0] = '0' + (memp_type/10);
+        strcat(errstr, digit);
+      }
+      digit[0] = '0' + (memp_type%10);
+      strcat(errstr, digit);
+#if defined(LWIP_DEBUG) && MEMP_STATS
+      strcat(errstr, memp_overflow_names[memp_type]);
+#endif
+      LWIP_ASSERT(errstr, 0);
+    }
+  }
+#endif
+}
+
+/**
+ * Do an overflow check for all elements in every pool.
+ *
+ * @see memp_overflow_check_element for a description of the check
+ */
+static void
+memp_overflow_check_all(void)
+{
+  u16_t i, j;
+  struct memp *p;
+
+  p = (struct memp *)LWIP_MEM_ALIGN(memp_memory);
+  for (i = 0; i < MEMP_MAX; ++i) {
+    p = p;
+    for (j = 0; j < memp_num[i]; ++j) {
+      memp_overflow_check_element_overflow(p, i);
+      p = (struct memp*)((u8_t*)p + MEMP_SIZE + memp_sizes[i] + MEMP_SANITY_REGION_AFTER_ALIGNED);
+    }
+  }
+  p = (struct memp *)LWIP_MEM_ALIGN(memp_memory);
+  for (i = 0; i < MEMP_MAX; ++i) {
+    p = p;
+    for (j = 0; j < memp_num[i]; ++j) {
+      memp_overflow_check_element_underflow(p, i);
+      p = (struct memp*)((u8_t*)p + MEMP_SIZE + memp_sizes[i] + MEMP_SANITY_REGION_AFTER_ALIGNED);
+    }
+  }
+}
+
+/**
+ * Initialize the restricted areas of all memp elements in every pool.
+ */
+static void
+memp_overflow_init(void)
+{
+  u16_t i, j;
+  struct memp *p;
+  u8_t *m;
+
+  p = (struct memp *)LWIP_MEM_ALIGN(memp_memory);
+  for (i = 0; i < MEMP_MAX; ++i) {
+    p = p;
+    for (j = 0; j < memp_num[i]; ++j) {
+#if MEMP_SANITY_REGION_BEFORE_ALIGNED > 0
+      m = (u8_t*)p + MEMP_SIZE - MEMP_SANITY_REGION_BEFORE_ALIGNED;
+      memset(m, 0xcd, MEMP_SANITY_REGION_BEFORE_ALIGNED);
+#endif
+#if MEMP_SANITY_REGION_AFTER_ALIGNED > 0
+      m = (u8_t*)p + MEMP_SIZE + memp_sizes[i];
+      memset(m, 0xcd, MEMP_SANITY_REGION_AFTER_ALIGNED);
+#endif
+      p = (struct memp*)((u8_t*)p + MEMP_SIZE + memp_sizes[i] + MEMP_SANITY_REGION_AFTER_ALIGNED);
+    }
+  }
+}
+#endif /* MEMP_OVERFLOW_CHECK */
+
+/**
+ * Initialize this module.
+ * 
+ * Carves out memp_memory into linked lists for each pool-type.
+ */
+void
+memp_init(void)
+{
+  struct memp *memp;
+  u16_t i, j;
+
+  for (i = 0; i < MEMP_MAX; ++i) {
+    MEMP_STATS_AVAIL(used, i, 0);
+    MEMP_STATS_AVAIL(max, i, 0);
+    MEMP_STATS_AVAIL(err, i, 0);
+    MEMP_STATS_AVAIL(avail, i, memp_num[i]);
+  }
+
+#if !MEMP_SEPARATE_POOLS
+  memp = (struct memp *)LWIP_MEM_ALIGN(memp_memory);
+#endif /* !MEMP_SEPARATE_POOLS */
+  /* for every pool: */
+  for (i = 0; i < MEMP_MAX; ++i) {
+    memp_tab[i] = NULL;
+#if MEMP_SEPARATE_POOLS
+    memp = (struct memp*)memp_bases[i];
+#endif /* MEMP_SEPARATE_POOLS */
+    /* create a linked list of memp elements */
+    for (j = 0; j < memp_num[i]; ++j) {
+      memp->next = memp_tab[i];
+      memp_tab[i] = memp;
+      memp = (struct memp *)(void *)((u8_t *)memp + MEMP_SIZE + memp_sizes[i]
+#if MEMP_OVERFLOW_CHECK
+        + MEMP_SANITY_REGION_AFTER_ALIGNED
+#endif
+      );
+    }
+  }
+#if MEMP_OVERFLOW_CHECK
+  memp_overflow_init();
+  /* check everything a first time to see if it worked */
+  memp_overflow_check_all();
+#endif /* MEMP_OVERFLOW_CHECK */
+}
+
+/**
+ * Get an element from a specific pool.
+ *
+ * @param type the pool to get an element from
+ *
+ * the debug version has two more parameters:
+ * @param file file name calling this function
+ * @param line number of line where this function is called
+ *
+ * @return a pointer to the allocated memory or a NULL pointer on error
+ */
+void *
+#if !MEMP_OVERFLOW_CHECK
+memp_malloc(memp_t type)
+#else
+memp_malloc_fn(memp_t type, const char* file, const int line)
+#endif
+{
+  struct memp *memp;
+  SYS_ARCH_DECL_PROTECT(old_level);
+ 
+  LWIP_ERROR("memp_malloc: type < MEMP_MAX", (type < MEMP_MAX), return NULL;);
+
+  SYS_ARCH_PROTECT(old_level);
+#if MEMP_OVERFLOW_CHECK >= 2
+  memp_overflow_check_all();
+#endif /* MEMP_OVERFLOW_CHECK >= 2 */
+
+  memp = memp_tab[type];
+  
+  if (memp != NULL) {
+    memp_tab[type] = memp->next;
+#if MEMP_OVERFLOW_CHECK
+    memp->next = NULL;
+    memp->file = file;
+    memp->line = line;
+#endif /* MEMP_OVERFLOW_CHECK */
+    MEMP_STATS_INC_USED(used, type);
+    LWIP_ASSERT("memp_malloc: memp properly aligned",
+                ((mem_ptr_t)memp % MEM_ALIGNMENT) == 0);
+    memp = (struct memp*)(void *)((u8_t*)memp + MEMP_SIZE);
+  } else {
+    LWIP_DEBUGF(MEMP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("memp_malloc: out of memory in pool %s\n", memp_desc[type]));
+    MEMP_STATS_INC(err, type);
+  }
+
+  SYS_ARCH_UNPROTECT(old_level);
+
+  return memp;
+}
+
+/**
+ * Put an element back into its pool.
+ *
+ * @param type the pool where to put mem
+ * @param mem the memp element to free
+ */
+void
+memp_free(memp_t type, void *mem)
+{
+  struct memp *memp;
+  SYS_ARCH_DECL_PROTECT(old_level);
+
+  if (mem == NULL) {
+    return;
+  }
+  LWIP_ASSERT("memp_free: mem properly aligned",
+                ((mem_ptr_t)mem % MEM_ALIGNMENT) == 0);
+
+  memp = (struct memp *)(void *)((u8_t*)mem - MEMP_SIZE);
+
+  SYS_ARCH_PROTECT(old_level);
+#if MEMP_OVERFLOW_CHECK
+#if MEMP_OVERFLOW_CHECK >= 2
+  memp_overflow_check_all();
+#else
+  memp_overflow_check_element_overflow(memp, type);
+  memp_overflow_check_element_underflow(memp, type);
+#endif /* MEMP_OVERFLOW_CHECK >= 2 */
+#endif /* MEMP_OVERFLOW_CHECK */
+
+  MEMP_STATS_DEC(used, type); 
+  
+  memp->next = memp_tab[type]; 
+  memp_tab[type] = memp;
+
+#if MEMP_SANITY_CHECK
+  LWIP_ASSERT("memp sanity", memp_sanity());
+#endif /* MEMP_SANITY_CHECK */
+
+  SYS_ARCH_UNPROTECT(old_level);
+}
+
+#endif /* MEMP_MEM_MALLOC */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/core/netif.c	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,752 @@
+/**
+ * @file
+ * lwIP network interface abstraction
+ *
+ */
+
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ *
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+
+#include "lwip/opt.h"
+
+#include "lwip/def.h"
+#include "lwip/ip_addr.h"
+#include "lwip/netif.h"
+#include "lwip/tcp_impl.h"
+#include "lwip/snmp.h"
+#include "lwip/igmp.h"
+#include "netif/etharp.h"
+#include "lwip/stats.h"
+#if ENABLE_LOOPBACK
+#include "lwip/sys.h"
+#if LWIP_NETIF_LOOPBACK_MULTITHREADING
+#include "lwip/tcpip.h"
+#endif /* LWIP_NETIF_LOOPBACK_MULTITHREADING */
+#endif /* ENABLE_LOOPBACK */
+
+#if LWIP_AUTOIP
+#include "lwip/autoip.h"
+#endif /* LWIP_AUTOIP */
+#if LWIP_DHCP
+#include "lwip/dhcp.h"
+#endif /* LWIP_DHCP */
+
+#if LWIP_NETIF_STATUS_CALLBACK
+#define NETIF_STATUS_CALLBACK(n) do{ if (n->status_callback) { (n->status_callback)(n); }}while(0)
+#else
+#define NETIF_STATUS_CALLBACK(n)
+#endif /* LWIP_NETIF_STATUS_CALLBACK */ 
+
+#if LWIP_NETIF_LINK_CALLBACK
+#define NETIF_LINK_CALLBACK(n) do{ if (n->link_callback) { (n->link_callback)(n); }}while(0)
+#else
+#define NETIF_LINK_CALLBACK(n)
+#endif /* LWIP_NETIF_LINK_CALLBACK */ 
+
+struct netif *netif_list;
+struct netif *netif_default;
+
+#if LWIP_HAVE_LOOPIF
+static struct netif loop_netif;
+
+/**
+ * Initialize a lwip network interface structure for a loopback interface
+ *
+ * @param netif the lwip network interface structure for this loopif
+ * @return ERR_OK if the loopif is initialized
+ *         ERR_MEM if private data couldn't be allocated
+ */
+static err_t
+netif_loopif_init(struct netif *netif)
+{
+  /* initialize the snmp variables and counters inside the struct netif
+   * ifSpeed: no assumption can be made!
+   */
+  NETIF_INIT_SNMP(netif, snmp_ifType_softwareLoopback, 0);
+
+  netif->name[0] = 'l';
+  netif->name[1] = 'o';
+  netif->output = netif_loop_output;
+  return ERR_OK;
+}
+#endif /* LWIP_HAVE_LOOPIF */
+
+void
+netif_init(void)
+{
+#if LWIP_HAVE_LOOPIF
+  ip_addr_t loop_ipaddr, loop_netmask, loop_gw;
+  IP4_ADDR(&loop_gw, 127,0,0,1);
+  IP4_ADDR(&loop_ipaddr, 127,0,0,1);
+  IP4_ADDR(&loop_netmask, 255,0,0,0);
+
+#if NO_SYS
+  netif_add(&loop_netif, &loop_ipaddr, &loop_netmask, &loop_gw, NULL, netif_loopif_init, ip_input);
+#else  /* NO_SYS */
+  netif_add(&loop_netif, &loop_ipaddr, &loop_netmask, &loop_gw, NULL, netif_loopif_init, tcpip_input);
+#endif /* NO_SYS */
+  netif_set_up(&loop_netif);
+
+#endif /* LWIP_HAVE_LOOPIF */
+}
+
+/**
+ * Add a network interface to the list of lwIP netifs.
+ *
+ * @param netif a pre-allocated netif structure
+ * @param ipaddr IP address for the new netif
+ * @param netmask network mask for the new netif
+ * @param gw default gateway IP address for the new netif
+ * @param state opaque data passed to the new netif
+ * @param init callback function that initializes the interface
+ * @param input callback function that is called to pass
+ * ingress packets up in the protocol layer stack.
+ *
+ * @return netif, or NULL if failed.
+ */
+struct netif *
+netif_add(struct netif *netif, ip_addr_t *ipaddr, ip_addr_t *netmask,
+  ip_addr_t *gw, void *state, netif_init_fn init, netif_input_fn input)
+{
+  static u8_t netifnum = 0;
+
+  LWIP_ASSERT("No init function given", init != NULL);
+
+  /* reset new interface configuration state */
+  ip_addr_set_zero(&netif->ip_addr);
+  ip_addr_set_zero(&netif->netmask);
+  ip_addr_set_zero(&netif->gw);
+  netif->flags = 0;
+#if LWIP_DHCP
+  /* netif not under DHCP control by default */
+  netif->dhcp = NULL;
+#endif /* LWIP_DHCP */
+#if LWIP_AUTOIP
+  /* netif not under AutoIP control by default */
+  netif->autoip = NULL;
+#endif /* LWIP_AUTOIP */
+#if LWIP_NETIF_STATUS_CALLBACK
+  netif->status_callback = NULL;
+#endif /* LWIP_NETIF_STATUS_CALLBACK */
+#if LWIP_NETIF_LINK_CALLBACK
+  netif->link_callback = NULL;
+#endif /* LWIP_NETIF_LINK_CALLBACK */
+#if LWIP_IGMP
+  netif->igmp_mac_filter = NULL;
+#endif /* LWIP_IGMP */
+#if ENABLE_LOOPBACK
+  netif->loop_first = NULL;
+  netif->loop_last = NULL;
+#endif /* ENABLE_LOOPBACK */
+
+  /* remember netif specific state information data */
+  netif->state = state;
+  netif->num = netifnum++;
+  netif->input = input;
+#if LWIP_NETIF_HWADDRHINT
+  netif->addr_hint = NULL;
+#endif /* LWIP_NETIF_HWADDRHINT*/
+#if ENABLE_LOOPBACK && LWIP_LOOPBACK_MAX_PBUFS
+  netif->loop_cnt_current = 0;
+#endif /* ENABLE_LOOPBACK && LWIP_LOOPBACK_MAX_PBUFS */
+
+  netif_set_addr(netif, ipaddr, netmask, gw);
+
+  /* call user specified initialization function for netif */
+  if (init(netif) != ERR_OK) {
+    return NULL;
+  }
+
+  /* add this netif to the list */
+  netif->next = netif_list;
+  netif_list = netif;
+  snmp_inc_iflist();
+
+#if LWIP_IGMP
+  /* start IGMP processing */
+  if (netif->flags & NETIF_FLAG_IGMP) {
+    igmp_start(netif);
+  }
+#endif /* LWIP_IGMP */
+
+  LWIP_DEBUGF(NETIF_DEBUG, ("netif: added interface %c%c IP addr ",
+    netif->name[0], netif->name[1]));
+  ip_addr_debug_print(NETIF_DEBUG, ipaddr);
+  LWIP_DEBUGF(NETIF_DEBUG, (" netmask "));
+  ip_addr_debug_print(NETIF_DEBUG, netmask);
+  LWIP_DEBUGF(NETIF_DEBUG, (" gw "));
+  ip_addr_debug_print(NETIF_DEBUG, gw);
+  LWIP_DEBUGF(NETIF_DEBUG, ("\n"));
+  return netif;
+}
+
+/**
+ * Change IP address configuration for a network interface (including netmask
+ * and default gateway).
+ *
+ * @param netif the network interface to change
+ * @param ipaddr the new IP address
+ * @param netmask the new netmask
+ * @param gw the new default gateway
+ */
+void
+netif_set_addr(struct netif *netif, ip_addr_t *ipaddr, ip_addr_t *netmask,
+    ip_addr_t *gw)
+{
+  netif_set_ipaddr(netif, ipaddr);
+  netif_set_netmask(netif, netmask);
+  netif_set_gw(netif, gw);
+}
+
+/**
+ * Remove a network interface from the list of lwIP netifs.
+ *
+ * @param netif the network interface to remove
+ */
+void
+netif_remove(struct netif *netif)
+{
+  if (netif == NULL) {
+    return;
+  }
+
+#if LWIP_IGMP
+  /* stop IGMP processing */
+  if (netif->flags & NETIF_FLAG_IGMP) {
+    igmp_stop(netif);
+  }
+#endif /* LWIP_IGMP */
+  if (netif_is_up(netif)) {
+    /* set netif down before removing (call callback function) */
+    netif_set_down(netif);
+  }
+
+  snmp_delete_ipaddridx_tree(netif);
+
+  /*  is it the first netif? */
+  if (netif_list == netif) {
+    netif_list = netif->next;
+  } else {
+    /*  look for netif further down the list */
+    struct netif * tmpNetif;
+    for (tmpNetif = netif_list; tmpNetif != NULL; tmpNetif = tmpNetif->next) {
+      if (tmpNetif->next == netif) {
+        tmpNetif->next = netif->next;
+        break;
+      }
+    }
+    if (tmpNetif == NULL)
+      return; /*  we didn't find any netif today */
+  }
+  snmp_dec_iflist();
+  /* this netif is default? */
+  if (netif_default == netif) {
+    /* reset default netif */
+    netif_set_default(NULL);
+  }
+  LWIP_DEBUGF( NETIF_DEBUG, ("netif_remove: removed netif\n") );
+}
+
+/**
+ * Find a network interface by searching for its name
+ *
+ * @param name the name of the netif (like netif->name) plus concatenated number
+ * in ascii representation (e.g. 'en0')
+ */
+struct netif *
+netif_find(char *name)
+{
+  struct netif *netif;
+  u8_t num;
+
+  if (name == NULL) {
+    return NULL;
+  }
+
+  num = name[2] - '0';
+
+  for(netif = netif_list; netif != NULL; netif = netif->next) {
+    if (num == netif->num &&
+       name[0] == netif->name[0] &&
+       name[1] == netif->name[1]) {
+      LWIP_DEBUGF(NETIF_DEBUG, ("netif_find: found %c%c\n", name[0], name[1]));
+      return netif;
+    }
+  }
+  LWIP_DEBUGF(NETIF_DEBUG, ("netif_find: didn't find %c%c\n", name[0], name[1]));
+  return NULL;
+}
+
+/**
+ * Change the IP address of a network interface
+ *
+ * @param netif the network interface to change
+ * @param ipaddr the new IP address
+ *
+ * @note call netif_set_addr() if you also want to change netmask and
+ * default gateway
+ */
+void
+netif_set_ipaddr(struct netif *netif, ip_addr_t *ipaddr)
+{
+  /* TODO: Handling of obsolete pcbs */
+  /* See:  http://mail.gnu.org/archive/html/lwip-users/2003-03/msg00118.html */
+#if LWIP_TCP
+  struct tcp_pcb *pcb;
+  struct tcp_pcb_listen *lpcb;
+
+  /* address is actually being changed? */
+  if ((ip_addr_cmp(ipaddr, &(netif->ip_addr))) == 0) {
+    /* extern struct tcp_pcb *tcp_active_pcbs; defined by tcp.h */
+    LWIP_DEBUGF(NETIF_DEBUG | LWIP_DBG_STATE, ("netif_set_ipaddr: netif address being changed\n"));
+    pcb = tcp_active_pcbs;
+    while (pcb != NULL) {
+      /* PCB bound to current local interface address? */
+      if (ip_addr_cmp(&(pcb->local_ip), &(netif->ip_addr))
+#if LWIP_AUTOIP
+        /* connections to link-local addresses must persist (RFC3927 ch. 1.9) */
+        && !ip_addr_islinklocal(&(pcb->local_ip))
+#endif /* LWIP_AUTOIP */
+        ) {
+        /* this connection must be aborted */
+        struct tcp_pcb *next = pcb->next;
+        LWIP_DEBUGF(NETIF_DEBUG | LWIP_DBG_STATE, ("netif_set_ipaddr: aborting TCP pcb %p\n", (void *)pcb));
+        tcp_abort(pcb);
+        pcb = next;
+      } else {
+        pcb = pcb->next;
+      }
+    }
+    for (lpcb = tcp_listen_pcbs.listen_pcbs; lpcb != NULL; lpcb = lpcb->next) {
+      /* PCB bound to current local interface address? */
+      if ((!(ip_addr_isany(&(lpcb->local_ip)))) &&
+          (ip_addr_cmp(&(lpcb->local_ip), &(netif->ip_addr)))) {
+        /* The PCB is listening to the old ipaddr and
+         * is set to listen to the new one instead */
+        ip_addr_set(&(lpcb->local_ip), ipaddr);
+      }
+    }
+  }
+#endif
+  snmp_delete_ipaddridx_tree(netif);
+  snmp_delete_iprteidx_tree(0,netif);
+  /* set new IP address to netif */
+  ip_addr_set(&(netif->ip_addr), ipaddr);
+  snmp_insert_ipaddridx_tree(netif);
+  snmp_insert_iprteidx_tree(0,netif);
+
+  LWIP_DEBUGF(NETIF_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("netif: IP address of interface %c%c set to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
+    netif->name[0], netif->name[1],
+    ip4_addr1_16(&netif->ip_addr),
+    ip4_addr2_16(&netif->ip_addr),
+    ip4_addr3_16(&netif->ip_addr),
+    ip4_addr4_16(&netif->ip_addr)));
+}
+
+/**
+ * Change the default gateway for a network interface
+ *
+ * @param netif the network interface to change
+ * @param gw the new default gateway
+ *
+ * @note call netif_set_addr() if you also want to change ip address and netmask
+ */
+void
+netif_set_gw(struct netif *netif, ip_addr_t *gw)
+{
+  ip_addr_set(&(netif->gw), gw);
+  LWIP_DEBUGF(NETIF_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("netif: GW address of interface %c%c set to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
+    netif->name[0], netif->name[1],
+    ip4_addr1_16(&netif->gw),
+    ip4_addr2_16(&netif->gw),
+    ip4_addr3_16(&netif->gw),
+    ip4_addr4_16(&netif->gw)));
+}
+
+/**
+ * Change the netmask of a network interface
+ *
+ * @param netif the network interface to change
+ * @param netmask the new netmask
+ *
+ * @note call netif_set_addr() if you also want to change ip address and
+ * default gateway
+ */
+void
+netif_set_netmask(struct netif *netif, ip_addr_t *netmask)
+{
+  snmp_delete_iprteidx_tree(0, netif);
+  /* set new netmask to netif */
+  ip_addr_set(&(netif->netmask), netmask);
+  snmp_insert_iprteidx_tree(0, netif);
+  LWIP_DEBUGF(NETIF_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("netif: netmask of interface %c%c set to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
+    netif->name[0], netif->name[1],
+    ip4_addr1_16(&netif->netmask),
+    ip4_addr2_16(&netif->netmask),
+    ip4_addr3_16(&netif->netmask),
+    ip4_addr4_16(&netif->netmask)));
+}
+
+/**
+ * Set a network interface as the default network interface
+ * (used to output all packets for which no specific route is found)
+ *
+ * @param netif the default network interface
+ */
+void
+netif_set_default(struct netif *netif)
+{
+  if (netif == NULL) {
+    /* remove default route */
+    snmp_delete_iprteidx_tree(1, netif);
+  } else {
+    /* install default route */
+    snmp_insert_iprteidx_tree(1, netif);
+  }
+  netif_default = netif;
+  LWIP_DEBUGF(NETIF_DEBUG, ("netif: setting default interface %c%c\n",
+           netif ? netif->name[0] : '\'', netif ? netif->name[1] : '\''));
+}
+
+/**
+ * Bring an interface up, available for processing
+ * traffic.
+ * 
+ * @note: Enabling DHCP on a down interface will make it come
+ * up once configured.
+ * 
+ * @see dhcp_start()
+ */ 
+void netif_set_up(struct netif *netif)
+{
+  if (!(netif->flags & NETIF_FLAG_UP)) {
+    netif->flags |= NETIF_FLAG_UP;
+    
+#if LWIP_SNMP
+    snmp_get_sysuptime(&netif->ts);
+#endif /* LWIP_SNMP */
+
+    NETIF_STATUS_CALLBACK(netif);
+
+    if (netif->flags & NETIF_FLAG_LINK_UP) {
+#if LWIP_ARP
+      /* For Ethernet network interfaces, we would like to send a "gratuitous ARP" */ 
+      if (netif->flags & (NETIF_FLAG_ETHARP)) {
+        etharp_gratuitous(netif);
+      }
+#endif /* LWIP_ARP */
+
+#if LWIP_IGMP
+      /* resend IGMP memberships */
+      if (netif->flags & NETIF_FLAG_IGMP) {
+        igmp_report_groups( netif);
+      }
+#endif /* LWIP_IGMP */
+    }
+  }
+}
+
+/**
+ * Bring an interface down, disabling any traffic processing.
+ *
+ * @note: Enabling DHCP on a down interface will make it come
+ * up once configured.
+ * 
+ * @see dhcp_start()
+ */ 
+void netif_set_down(struct netif *netif)
+{
+  if (netif->flags & NETIF_FLAG_UP) {
+    netif->flags &= ~NETIF_FLAG_UP;
+#if LWIP_SNMP
+    snmp_get_sysuptime(&netif->ts);
+#endif
+
+    NETIF_STATUS_CALLBACK(netif);
+  }
+}
+
+#if LWIP_NETIF_STATUS_CALLBACK
+/**
+ * Set callback to be called when interface is brought up/down
+ */
+void netif_set_status_callback(struct netif *netif, netif_status_callback_fn status_callback)
+{
+  if (netif) {
+    netif->status_callback = status_callback;
+  }
+}
+#endif /* LWIP_NETIF_STATUS_CALLBACK */
+
+/**
+ * Called by a driver when its link goes up
+ */
+void netif_set_link_up(struct netif *netif )
+{
+  if (!(netif->flags & NETIF_FLAG_LINK_UP)) {
+    netif->flags |= NETIF_FLAG_LINK_UP;
+
+#if LWIP_DHCP
+    if (netif->dhcp) {
+      dhcp_network_changed(netif);
+    }
+#endif /* LWIP_DHCP */
+
+#if LWIP_AUTOIP
+    if (netif->autoip) {
+      autoip_network_changed(netif);
+    }
+#endif /* LWIP_AUTOIP */
+
+    if (netif->flags & NETIF_FLAG_UP) {
+#if LWIP_ARP
+      /* For Ethernet network interfaces, we would like to send a "gratuitous ARP" */ 
+      if (netif->flags & NETIF_FLAG_ETHARP) {
+        etharp_gratuitous(netif);
+      }
+#endif /* LWIP_ARP */
+
+#if LWIP_IGMP
+      /* resend IGMP memberships */
+      if (netif->flags & NETIF_FLAG_IGMP) {
+        igmp_report_groups( netif);
+      }
+#endif /* LWIP_IGMP */
+    }
+    NETIF_LINK_CALLBACK(netif);
+  }
+}
+
+/**
+ * Called by a driver when its link goes down
+ */
+void netif_set_link_down(struct netif *netif )
+{
+  if (netif->flags & NETIF_FLAG_LINK_UP) {
+    netif->flags &= ~NETIF_FLAG_LINK_UP;
+    NETIF_LINK_CALLBACK(netif);
+  }
+}
+
+#if LWIP_NETIF_LINK_CALLBACK
+/**
+ * Set callback to be called when link is brought up/down
+ */
+void netif_set_link_callback(struct netif *netif, netif_status_callback_fn link_callback)
+{
+  if (netif) {
+    netif->link_callback = link_callback;
+  }
+}
+#endif /* LWIP_NETIF_LINK_CALLBACK */
+
+#if ENABLE_LOOPBACK
+/**
+ * Send an IP packet to be received on the same netif (loopif-like).
+ * The pbuf is simply copied and handed back to netif->input.
+ * In multithreaded mode, this is done directly since netif->input must put
+ * the packet on a queue.
+ * In callback mode, the packet is put on an internal queue and is fed to
+ * netif->input by netif_poll().
+ *
+ * @param netif the lwip network interface structure
+ * @param p the (IP) packet to 'send'
+ * @param ipaddr the ip address to send the packet to (not used)
+ * @return ERR_OK if the packet has been sent
+ *         ERR_MEM if the pbuf used to copy the packet couldn't be allocated
+ */
+err_t
+netif_loop_output(struct netif *netif, struct pbuf *p,
+       ip_addr_t *ipaddr)
+{
+  struct pbuf *r;
+  err_t err;
+  struct pbuf *last;
+#if LWIP_LOOPBACK_MAX_PBUFS
+  u8_t clen = 0;
+#endif /* LWIP_LOOPBACK_MAX_PBUFS */
+  /* If we have a loopif, SNMP counters are adjusted for it,
+   * if not they are adjusted for 'netif'. */
+#if LWIP_SNMP
+#if LWIP_HAVE_LOOPIF
+  struct netif *stats_if = &loop_netif;
+#else /* LWIP_HAVE_LOOPIF */
+  struct netif *stats_if = netif;
+#endif /* LWIP_HAVE_LOOPIF */
+#endif /* LWIP_SNMP */
+  SYS_ARCH_DECL_PROTECT(lev);
+  LWIP_UNUSED_ARG(ipaddr);
+
+  /* Allocate a new pbuf */
+  r = pbuf_alloc(PBUF_LINK, p->tot_len, PBUF_RAM);
+  if (r == NULL) {
+    LINK_STATS_INC(link.memerr);
+    LINK_STATS_INC(link.drop);
+    snmp_inc_ifoutdiscards(stats_if);
+    return ERR_MEM;
+  }
+#if LWIP_LOOPBACK_MAX_PBUFS
+  clen = pbuf_clen(r);
+  /* check for overflow or too many pbuf on queue */
+  if(((netif->loop_cnt_current + clen) < netif->loop_cnt_current) ||
+     ((netif->loop_cnt_current + clen) > LWIP_LOOPBACK_MAX_PBUFS)) {
+    pbuf_free(r);
+    LINK_STATS_INC(link.memerr);
+    LINK_STATS_INC(link.drop);
+    snmp_inc_ifoutdiscards(stats_if);
+    return ERR_MEM;
+  }
+  netif->loop_cnt_current += clen;
+#endif /* LWIP_LOOPBACK_MAX_PBUFS */
+
+  /* Copy the whole pbuf queue p into the single pbuf r */
+  if ((err = pbuf_copy(r, p)) != ERR_OK) {
+    pbuf_free(r);
+    LINK_STATS_INC(link.memerr);
+    LINK_STATS_INC(link.drop);
+    snmp_inc_ifoutdiscards(stats_if);
+    return err;
+  }
+
+  /* Put the packet on a linked list which gets emptied through calling
+     netif_poll(). */
+
+  /* let last point to the last pbuf in chain r */
+  for (last = r; last->next != NULL; last = last->next);
+
+  SYS_ARCH_PROTECT(lev);
+  if(netif->loop_first != NULL) {
+    LWIP_ASSERT("if first != NULL, last must also be != NULL", netif->loop_last != NULL);
+    netif->loop_last->next = r;
+    netif->loop_last = last;
+  } else {
+    netif->loop_first = r;
+    netif->loop_last = last;
+  }
+  SYS_ARCH_UNPROTECT(lev);
+
+  LINK_STATS_INC(link.xmit);
+  snmp_add_ifoutoctets(stats_if, p->tot_len);
+  snmp_inc_ifoutucastpkts(stats_if);
+
+#if LWIP_NETIF_LOOPBACK_MULTITHREADING
+  /* For multithreading environment, schedule a call to netif_poll */
+  tcpip_callback((tcpip_callback_fn)netif_poll, netif);
+#endif /* LWIP_NETIF_LOOPBACK_MULTITHREADING */
+
+  return ERR_OK;
+}
+
+/**
+ * Call netif_poll() in the main loop of your application. This is to prevent
+ * reentering non-reentrant functions like tcp_input(). Packets passed to
+ * netif_loop_output() are put on a list that is passed to netif->input() by
+ * netif_poll().
+ */
+void
+netif_poll(struct netif *netif)
+{
+  struct pbuf *in;
+  /* If we have a loopif, SNMP counters are adjusted for it,
+   * if not they are adjusted for 'netif'. */
+#if LWIP_SNMP
+#if LWIP_HAVE_LOOPIF
+  struct netif *stats_if = &loop_netif;
+#else /* LWIP_HAVE_LOOPIF */
+  struct netif *stats_if = netif;
+#endif /* LWIP_HAVE_LOOPIF */
+#endif /* LWIP_SNMP */
+  SYS_ARCH_DECL_PROTECT(lev);
+
+  do {
+    /* Get a packet from the list. With SYS_LIGHTWEIGHT_PROT=1, this is protected */
+    SYS_ARCH_PROTECT(lev);
+    in = netif->loop_first;
+    if (in != NULL) {
+      struct pbuf *in_end = in;
+#if LWIP_LOOPBACK_MAX_PBUFS
+      u8_t clen = pbuf_clen(in);
+      /* adjust the number of pbufs on queue */
+      LWIP_ASSERT("netif->loop_cnt_current underflow",
+        ((netif->loop_cnt_current - clen) < netif->loop_cnt_current));
+      netif->loop_cnt_current -= clen;
+#endif /* LWIP_LOOPBACK_MAX_PBUFS */
+      while (in_end->len != in_end->tot_len) {
+        LWIP_ASSERT("bogus pbuf: len != tot_len but next == NULL!", in_end->next != NULL);
+        in_end = in_end->next;
+      }
+      /* 'in_end' now points to the last pbuf from 'in' */
+      if (in_end == netif->loop_last) {
+        /* this was the last pbuf in the list */
+        netif->loop_first = netif->loop_last = NULL;
+      } else {
+        /* pop the pbuf off the list */
+        netif->loop_first = in_end->next;
+        LWIP_ASSERT("should not be null since first != last!", netif->loop_first != NULL);
+      }
+      /* De-queue the pbuf from its successors on the 'loop_' list. */
+      in_end->next = NULL;
+    }
+    SYS_ARCH_UNPROTECT(lev);
+
+    if (in != NULL) {
+      LINK_STATS_INC(link.recv);
+      snmp_add_ifinoctets(stats_if, in->tot_len);
+      snmp_inc_ifinucastpkts(stats_if);
+      /* loopback packets are always IP packets! */
+      if (ip_input(in, netif) != ERR_OK) {
+        pbuf_free(in);
+      }
+      /* Don't reference the packet any more! */
+      in = NULL;
+    }
+  /* go on while there is a packet on the list */
+  } while (netif->loop_first != NULL);
+}
+
+#if !LWIP_NETIF_LOOPBACK_MULTITHREADING
+/**
+ * Calls netif_poll() for every netif on the netif_list.
+ */
+void
+netif_poll_all(void)
+{
+  struct netif *netif = netif_list;
+  /* loop through netifs */
+  while (netif != NULL) {
+    netif_poll(netif);
+    /* proceed to next network interface */
+    netif = netif->next;
+  }
+}
+#endif /* !LWIP_NETIF_LOOPBACK_MULTITHREADING */
+#endif /* ENABLE_LOOPBACK */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/core/pbuf.c	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,1156 @@
+/**
+ * @file
+ * Packet buffer management
+ *
+ * Packets are built from the pbuf data structure. It supports dynamic
+ * memory allocation for packet contents or can reference externally
+ * managed packet contents both in RAM and ROM. Quick allocation for
+ * incoming packets is provided through pools with fixed sized pbufs.
+ *
+ * A packet may span over multiple pbufs, chained as a singly linked
+ * list. This is called a "pbuf chain".
+ *
+ * Multiple packets may be queued, also using this singly linked list.
+ * This is called a "packet queue".
+ * 
+ * So, a packet queue consists of one or more pbuf chains, each of
+ * which consist of one or more pbufs. CURRENTLY, PACKET QUEUES ARE
+ * NOT SUPPORTED!!! Use helper structs to queue multiple packets.
+ * 
+ * The differences between a pbuf chain and a packet queue are very
+ * precise but subtle. 
+ *
+ * The last pbuf of a packet has a ->tot_len field that equals the
+ * ->len field. It can be found by traversing the list. If the last
+ * pbuf of a packet has a ->next field other than NULL, more packets
+ * are on the queue.
+ *
+ * Therefore, looping through a pbuf of a single packet, has an
+ * loop end condition (tot_len == p->len), NOT (next == NULL).
+ */
+
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ *
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+
+#include "lwip/opt.h"
+
+#include "lwip/stats.h"
+#include "lwip/def.h"
+#include "lwip/mem.h"
+#include "lwip/memp.h"
+#include "lwip/pbuf.h"
+#include "lwip/sys.h"
+#include "arch/perf.h"
+#if TCP_QUEUE_OOSEQ
+#include "lwip/tcp_impl.h"
+#endif
+#if LWIP_CHECKSUM_ON_COPY
+#include "lwip/inet_chksum.h"
+#endif
+
+#include <string.h>
+
+#define SIZEOF_STRUCT_PBUF        LWIP_MEM_ALIGN_SIZE(sizeof(struct pbuf))
+/* Since the pool is created in memp, PBUF_POOL_BUFSIZE will be automatically
+   aligned there. Therefore, PBUF_POOL_BUFSIZE_ALIGNED can be used here. */
+#define PBUF_POOL_BUFSIZE_ALIGNED LWIP_MEM_ALIGN_SIZE(PBUF_POOL_BUFSIZE)
+
+#if !LWIP_TCP || !TCP_QUEUE_OOSEQ || NO_SYS
+#define PBUF_POOL_IS_EMPTY()
+#else /* !LWIP_TCP || !TCP_QUEUE_OOSEQ || NO_SYS */
+/** Define this to 0 to prevent freeing ooseq pbufs when the PBUF_POOL is empty */
+#ifndef PBUF_POOL_FREE_OOSEQ
+#define PBUF_POOL_FREE_OOSEQ 1
+#endif /* PBUF_POOL_FREE_OOSEQ */
+
+#if PBUF_POOL_FREE_OOSEQ
+#include "lwip/tcpip.h"
+#define PBUF_POOL_IS_EMPTY() pbuf_pool_is_empty()
+static u8_t pbuf_free_ooseq_queued;
+/**
+ * Attempt to reclaim some memory from queued out-of-sequence TCP segments
+ * if we run out of pool pbufs. It's better to give priority to new packets
+ * if we're running out.
+ *
+ * This must be done in the correct thread context therefore this function
+ * can only be used with NO_SYS=0 and through tcpip_callback.
+ */
+static void
+pbuf_free_ooseq(void* arg)
+{
+  struct tcp_pcb* pcb;
+  SYS_ARCH_DECL_PROTECT(old_level);
+  LWIP_UNUSED_ARG(arg);
+
+  SYS_ARCH_PROTECT(old_level);
+  pbuf_free_ooseq_queued = 0;
+  SYS_ARCH_UNPROTECT(old_level);
+
+  for (pcb = tcp_active_pcbs; NULL != pcb; pcb = pcb->next) {
+    if (NULL != pcb->ooseq) {
+      /** Free the ooseq pbufs of one PCB only */
+      LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_free_ooseq: freeing out-of-sequence pbufs\n"));
+      tcp_segs_free(pcb->ooseq);
+      pcb->ooseq = NULL;
+      return;
+    }
+  }
+}
+
+/** Queue a call to pbuf_free_ooseq if not already queued. */
+static void
+pbuf_pool_is_empty(void)
+{
+  u8_t queued;
+  SYS_ARCH_DECL_PROTECT(old_level);
+
+  SYS_ARCH_PROTECT(old_level);
+  queued = pbuf_free_ooseq_queued;
+  pbuf_free_ooseq_queued = 1;
+  SYS_ARCH_UNPROTECT(old_level);
+
+  if(!queued) {
+    /* queue a call to pbuf_free_ooseq if not already queued */
+    if(tcpip_callback_with_block(pbuf_free_ooseq, NULL, 0) != ERR_OK) {
+      SYS_ARCH_PROTECT(old_level);
+      pbuf_free_ooseq_queued = 0;
+      SYS_ARCH_UNPROTECT(old_level);
+    }
+  }
+}
+#endif /* PBUF_POOL_FREE_OOSEQ */
+#endif /* !LWIP_TCP || !TCP_QUEUE_OOSEQ || NO_SYS */
+
+/**
+ * Allocates a pbuf of the given type (possibly a chain for PBUF_POOL type).
+ *
+ * The actual memory allocated for the pbuf is determined by the
+ * layer at which the pbuf is allocated and the requested size
+ * (from the size parameter).
+ *
+ * @param layer flag to define header size
+ * @param length size of the pbuf's payload
+ * @param type this parameter decides how and where the pbuf
+ * should be allocated as follows:
+ *
+ * - PBUF_RAM: buffer memory for pbuf is allocated as one large
+ *             chunk. This includes protocol headers as well.
+ * - PBUF_ROM: no buffer memory is allocated for the pbuf, even for
+ *             protocol headers. Additional headers must be prepended
+ *             by allocating another pbuf and chain in to the front of
+ *             the ROM pbuf. It is assumed that the memory used is really
+ *             similar to ROM in that it is immutable and will not be
+ *             changed. Memory which is dynamic should generally not
+ *             be attached to PBUF_ROM pbufs. Use PBUF_REF instead.
+ * - PBUF_REF: no buffer memory is allocated for the pbuf, even for
+ *             protocol headers. It is assumed that the pbuf is only
+ *             being used in a single thread. If the pbuf gets queued,
+ *             then pbuf_take should be called to copy the buffer.
+ * - PBUF_POOL: the pbuf is allocated as a pbuf chain, with pbufs from
+ *              the pbuf pool that is allocated during pbuf_init().
+ *
+ * @return the allocated pbuf. If multiple pbufs where allocated, this
+ * is the first pbuf of a pbuf chain.
+ */
+struct pbuf *
+pbuf_alloc(pbuf_layer layer, u16_t length, pbuf_type type)
+{
+  struct pbuf *p, *q, *r;
+  u16_t offset;
+  s32_t rem_len; /* remaining length */
+  LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_alloc(length=%"U16_F")\n", length));
+
+  /* determine header offset */
+  offset = 0;
+  switch (layer) {
+  case PBUF_TRANSPORT:
+    /* add room for transport (often TCP) layer header */
+    offset += PBUF_TRANSPORT_HLEN;
+    /* FALLTHROUGH */
+  case PBUF_IP:
+    /* add room for IP layer header */
+    offset += PBUF_IP_HLEN;
+    /* FALLTHROUGH */
+  case PBUF_LINK:
+    /* add room for link layer header */
+    offset += PBUF_LINK_HLEN;
+    break;
+  case PBUF_RAW:
+    break;
+  default:
+    LWIP_ASSERT("pbuf_alloc: bad pbuf layer", 0);
+    return NULL;
+  }
+
+  switch (type) {
+  case PBUF_POOL:
+    /* allocate head of pbuf chain into p */
+    p = (struct pbuf *)memp_malloc(MEMP_PBUF_POOL);
+    LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_alloc: allocated pbuf %p\n", (void *)p));
+    if (p == NULL) {
+      PBUF_POOL_IS_EMPTY();
+      return NULL;
+    }
+    p->type = type;
+    p->next = NULL;
+
+    /* make the payload pointer point 'offset' bytes into pbuf data memory */
+    p->payload = LWIP_MEM_ALIGN((void *)((u8_t *)p + (SIZEOF_STRUCT_PBUF + offset)));
+    LWIP_ASSERT("pbuf_alloc: pbuf p->payload properly aligned",
+            ((mem_ptr_t)p->payload % MEM_ALIGNMENT) == 0);
+    /* the total length of the pbuf chain is the requested size */
+    p->tot_len = length;
+    /* set the length of the first pbuf in the chain */
+    p->len = LWIP_MIN(length, PBUF_POOL_BUFSIZE_ALIGNED - LWIP_MEM_ALIGN_SIZE(offset));
+    LWIP_ASSERT("check p->payload + p->len does not overflow pbuf",
+                ((u8_t*)p->payload + p->len <=
+                 (u8_t*)p + SIZEOF_STRUCT_PBUF + PBUF_POOL_BUFSIZE_ALIGNED));
+    LWIP_ASSERT("PBUF_POOL_BUFSIZE must be bigger than MEM_ALIGNMENT",
+      (PBUF_POOL_BUFSIZE_ALIGNED - LWIP_MEM_ALIGN_SIZE(offset)) > 0 );
+    /* set reference count (needed here in case we fail) */
+    p->ref = 1;
+
+    /* now allocate the tail of the pbuf chain */
+
+    /* remember first pbuf for linkage in next iteration */
+    r = p;
+    /* remaining length to be allocated */
+    rem_len = length - p->len;
+    /* any remaining pbufs to be allocated? */
+    while (rem_len > 0) {
+      q = (struct pbuf *)memp_malloc(MEMP_PBUF_POOL);
+      if (q == NULL) {
+        PBUF_POOL_IS_EMPTY();
+        /* free chain so far allocated */
+        pbuf_free(p);
+        /* bail out unsuccesfully */
+        return NULL;
+      }
+      q->type = type;
+      q->flags = 0;
+      q->next = NULL;
+      /* make previous pbuf point to this pbuf */
+      r->next = q;
+      /* set total length of this pbuf and next in chain */
+      LWIP_ASSERT("rem_len < max_u16_t", rem_len < 0xffff);
+      q->tot_len = (u16_t)rem_len;
+      /* this pbuf length is pool size, unless smaller sized tail */
+      q->len = LWIP_MIN((u16_t)rem_len, PBUF_POOL_BUFSIZE_ALIGNED);
+      q->payload = (void *)((u8_t *)q + SIZEOF_STRUCT_PBUF);
+      LWIP_ASSERT("pbuf_alloc: pbuf q->payload properly aligned",
+              ((mem_ptr_t)q->payload % MEM_ALIGNMENT) == 0);
+      LWIP_ASSERT("check p->payload + p->len does not overflow pbuf",
+                  ((u8_t*)p->payload + p->len <=
+                   (u8_t*)p + SIZEOF_STRUCT_PBUF + PBUF_POOL_BUFSIZE_ALIGNED));
+      q->ref = 1;
+      /* calculate remaining length to be allocated */
+      rem_len -= q->len;
+      /* remember this pbuf for linkage in next iteration */
+      r = q;
+    }
+    /* end of chain */
+    /*r->next = NULL;*/
+
+    break;
+  case PBUF_RAM:
+    /* If pbuf is to be allocated in RAM, allocate memory for it. */
+    p = (struct pbuf*)mem_malloc(LWIP_MEM_ALIGN_SIZE(SIZEOF_STRUCT_PBUF + offset) + LWIP_MEM_ALIGN_SIZE(length));
+    if (p == NULL) {
+      return NULL;
+    }
+    /* Set up internal structure of the pbuf. */
+    p->payload = LWIP_MEM_ALIGN((void *)((u8_t *)p + SIZEOF_STRUCT_PBUF + offset));
+    p->len = p->tot_len = length;
+    p->next = NULL;
+    p->type = type;
+
+    LWIP_ASSERT("pbuf_alloc: pbuf->payload properly aligned",
+           ((mem_ptr_t)p->payload % MEM_ALIGNMENT) == 0);
+    break;
+  /* pbuf references existing (non-volatile static constant) ROM payload? */
+  case PBUF_ROM:
+  /* pbuf references existing (externally allocated) RAM payload? */
+  case PBUF_REF:
+    /* only allocate memory for the pbuf structure */
+    p = (struct pbuf *)memp_malloc(MEMP_PBUF);
+    if (p == NULL) {
+      LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
+                  ("pbuf_alloc: Could not allocate MEMP_PBUF for PBUF_%s.\n",
+                  (type == PBUF_ROM) ? "ROM" : "REF"));
+      return NULL;
+    }
+    /* caller must set this field properly, afterwards */
+    p->payload = NULL;
+    p->len = p->tot_len = length;
+    p->next = NULL;
+    p->type = type;
+    break;
+  default:
+    LWIP_ASSERT("pbuf_alloc: erroneous type", 0);
+    return NULL;
+  }
+  /* set reference count */
+  p->ref = 1;
+  /* set flags */
+  p->flags = 0;
+  LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_alloc(length=%"U16_F") == %p\n", length, (void *)p));
+  return p;
+}
+
+#if LWIP_SUPPORT_CUSTOM_PBUF
+/** Initialize a custom pbuf (already allocated).
+ *
+ * @param layer flag to define header size
+ * @param length size of the pbuf's payload
+ * @param type type of the pbuf (only used to treat the pbuf accordingly, as
+ *        this function allocates no memory)
+ * @param p pointer to the custom pbuf to initialize (already allocated)
+ * @param payload_mem pointer to the buffer that is used for payload and headers,
+ *        must be at least big enough to hold 'length' plus the header size,
+ *        may be NULL if set later
+ * @param payload_mem_len the size of the 'payload_mem' buffer, must be at least
+ *        big enough to hold 'length' plus the header size
+ */
+struct pbuf*
+pbuf_alloced_custom(pbuf_layer l, u16_t length, pbuf_type type, struct pbuf_custom *p,
+                    void *payload_mem, u16_t payload_mem_len)
+{
+  u16_t offset;
+  LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_alloced_custom(length=%"U16_F")\n", length));
+
+  /* determine header offset */
+  offset = 0;
+  switch (l) {
+  case PBUF_TRANSPORT:
+    /* add room for transport (often TCP) layer header */
+    offset += PBUF_TRANSPORT_HLEN;
+    /* FALLTHROUGH */
+  case PBUF_IP:
+    /* add room for IP layer header */
+    offset += PBUF_IP_HLEN;
+    /* FALLTHROUGH */
+  case PBUF_LINK:
+    /* add room for link layer header */
+    offset += PBUF_LINK_HLEN;
+    break;
+  case PBUF_RAW:
+    break;
+  default:
+    LWIP_ASSERT("pbuf_alloced_custom: bad pbuf layer", 0);
+    return NULL;
+  }
+
+  if (LWIP_MEM_ALIGN_SIZE(offset) + length < payload_mem_len) {
+    LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_LEVEL_WARNING, ("pbuf_alloced_custom(length=%"U16_F") buffer too short\n", length));
+    return NULL;
+  }
+
+  p->pbuf.next = NULL;
+  if (payload_mem != NULL) {
+    p->pbuf.payload = LWIP_MEM_ALIGN((void *)((u8_t *)payload_mem + offset));
+  } else {
+    p->pbuf.payload = NULL;
+  }
+  p->pbuf.flags = PBUF_FLAG_IS_CUSTOM;
+  p->pbuf.len = p->pbuf.tot_len = length;
+  p->pbuf.type = type;
+  p->pbuf.ref = 1;
+  return &p->pbuf;
+}
+#endif /* LWIP_SUPPORT_CUSTOM_PBUF */
+
+/**
+ * Shrink a pbuf chain to a desired length.
+ *
+ * @param p pbuf to shrink.
+ * @param new_len desired new length of pbuf chain
+ *
+ * Depending on the desired length, the first few pbufs in a chain might
+ * be skipped and left unchanged. The new last pbuf in the chain will be
+ * resized, and any remaining pbufs will be freed.
+ *
+ * @note If the pbuf is ROM/REF, only the ->tot_len and ->len fields are adjusted.
+ * @note May not be called on a packet queue.
+ *
+ * @note Despite its name, pbuf_realloc cannot grow the size of a pbuf (chain).
+ */
+void
+pbuf_realloc(struct pbuf *p, u16_t new_len)
+{
+  struct pbuf *q;
+  u16_t rem_len; /* remaining length */
+  s32_t grow;
+
+  LWIP_ASSERT("pbuf_realloc: p != NULL", p != NULL);
+  LWIP_ASSERT("pbuf_realloc: sane p->type", p->type == PBUF_POOL ||
+              p->type == PBUF_ROM ||
+              p->type == PBUF_RAM ||
+              p->type == PBUF_REF);
+
+  /* desired length larger than current length? */
+  if (new_len >= p->tot_len) {
+    /* enlarging not yet supported */
+    return;
+  }
+
+  /* the pbuf chain grows by (new_len - p->tot_len) bytes
+   * (which may be negative in case of shrinking) */
+  grow = new_len - p->tot_len;
+
+  /* first, step over any pbufs that should remain in the chain */
+  rem_len = new_len;
+  q = p;
+  /* should this pbuf be kept? */
+  while (rem_len > q->len) {
+    /* decrease remaining length by pbuf length */
+    rem_len -= q->len;
+    /* decrease total length indicator */
+    LWIP_ASSERT("grow < max_u16_t", grow < 0xffff);
+    q->tot_len += (u16_t)grow;
+    /* proceed to next pbuf in chain */
+    q = q->next;
+    LWIP_ASSERT("pbuf_realloc: q != NULL", q != NULL);
+  }
+  /* we have now reached the new last pbuf (in q) */
+  /* rem_len == desired length for pbuf q */
+
+  /* shrink allocated memory for PBUF_RAM */
+  /* (other types merely adjust their length fields */
+  if ((q->type == PBUF_RAM) && (rem_len != q->len)) {
+    /* reallocate and adjust the length of the pbuf that will be split */
+    q = (struct pbuf *)mem_trim(q, (u16_t)((u8_t *)q->payload - (u8_t *)q) + rem_len);
+    LWIP_ASSERT("mem_trim returned q == NULL", q != NULL);
+  }
+  /* adjust length fields for new last pbuf */
+  q->len = rem_len;
+  q->tot_len = q->len;
+
+  /* any remaining pbufs in chain? */
+  if (q->next != NULL) {
+    /* free remaining pbufs in chain */
+    pbuf_free(q->next);
+  }
+  /* q is last packet in chain */
+  q->next = NULL;
+
+}
+
+/**
+ * Adjusts the payload pointer to hide or reveal headers in the payload.
+ *
+ * Adjusts the ->payload pointer so that space for a header
+ * (dis)appears in the pbuf payload.
+ *
+ * The ->payload, ->tot_len and ->len fields are adjusted.
+ *
+ * @param p pbuf to change the header size.
+ * @param header_size_increment Number of bytes to increment header size which
+ * increases the size of the pbuf. New space is on the front.
+ * (Using a negative value decreases the header size.)
+ * If hdr_size_inc is 0, this function does nothing and returns succesful.
+ *
+ * PBUF_ROM and PBUF_REF type buffers cannot have their sizes increased, so
+ * the call will fail. A check is made that the increase in header size does
+ * not move the payload pointer in front of the start of the buffer.
+ * @return non-zero on failure, zero on success.
+ *
+ */
+u8_t
+pbuf_header(struct pbuf *p, s16_t header_size_increment)
+{
+  u16_t type;
+  void *payload;
+  u16_t increment_magnitude;
+
+  LWIP_ASSERT("p != NULL", p != NULL);
+  if ((header_size_increment == 0) || (p == NULL)) {
+    return 0;
+  }
+ 
+  if (header_size_increment < 0){
+    increment_magnitude = -header_size_increment;
+    /* Check that we aren't going to move off the end of the pbuf */
+    LWIP_ERROR("increment_magnitude <= p->len", (increment_magnitude <= p->len), return 1;);
+  } else {
+    increment_magnitude = header_size_increment;
+#if 0
+    /* Can't assert these as some callers speculatively call
+         pbuf_header() to see if it's OK.  Will return 1 below instead. */
+    /* Check that we've got the correct type of pbuf to work with */
+    LWIP_ASSERT("p->type == PBUF_RAM || p->type == PBUF_POOL", 
+                p->type == PBUF_RAM || p->type == PBUF_POOL);
+    /* Check that we aren't going to move off the beginning of the pbuf */
+    LWIP_ASSERT("p->payload - increment_magnitude >= p + SIZEOF_STRUCT_PBUF",
+                (u8_t *)p->payload - increment_magnitude >= (u8_t *)p + SIZEOF_STRUCT_PBUF);
+#endif
+  }
+
+  type = p->type;
+  /* remember current payload pointer */
+  payload = p->payload;
+
+  /* pbuf types containing payloads? */
+  if (type == PBUF_RAM || type == PBUF_POOL) {
+    /* set new payload pointer */
+    p->payload = (u8_t *)p->payload - header_size_increment;
+    /* boundary check fails? */
+    if ((u8_t *)p->payload < (u8_t *)p + SIZEOF_STRUCT_PBUF) {
+      LWIP_DEBUGF( PBUF_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
+        ("pbuf_header: failed as %p < %p (not enough space for new header size)\n",
+        (void *)p->payload, (void *)(p + 1)));
+      /* restore old payload pointer */
+      p->payload = payload;
+      /* bail out unsuccesfully */
+      return 1;
+    }
+  /* pbuf types refering to external payloads? */
+  } else if (type == PBUF_REF || type == PBUF_ROM) {
+    /* hide a header in the payload? */
+    if ((header_size_increment < 0) && (increment_magnitude <= p->len)) {
+      /* increase payload pointer */
+      p->payload = (u8_t *)p->payload - header_size_increment;
+    } else {
+      /* cannot expand payload to front (yet!)
+       * bail out unsuccesfully */
+      return 1;
+    }
+  } else {
+    /* Unknown type */
+    LWIP_ASSERT("bad pbuf type", 0);
+    return 1;
+  }
+  /* modify pbuf length fields */
+  p->len += header_size_increment;
+  p->tot_len += header_size_increment;
+
+  LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_header: old %p new %p (%"S16_F")\n",
+    (void *)payload, (void *)p->payload, header_size_increment));
+
+  return 0;
+}
+
+/**
+ * Dereference a pbuf chain or queue and deallocate any no-longer-used
+ * pbufs at the head of this chain or queue.
+ *
+ * Decrements the pbuf reference count. If it reaches zero, the pbuf is
+ * deallocated.
+ *
+ * For a pbuf chain, this is repeated for each pbuf in the chain,
+ * up to the first pbuf which has a non-zero reference count after
+ * decrementing. So, when all reference counts are one, the whole
+ * chain is free'd.
+ *
+ * @param p The pbuf (chain) to be dereferenced.
+ *
+ * @return the number of pbufs that were de-allocated
+ * from the head of the chain.
+ *
+ * @note MUST NOT be called on a packet queue (Not verified to work yet).
+ * @note the reference counter of a pbuf equals the number of pointers
+ * that refer to the pbuf (or into the pbuf).
+ *
+ * @internal examples:
+ *
+ * Assuming existing chains a->b->c with the following reference
+ * counts, calling pbuf_free(a) results in:
+ * 
+ * 1->2->3 becomes ...1->3
+ * 3->3->3 becomes 2->3->3
+ * 1->1->2 becomes ......1
+ * 2->1->1 becomes 1->1->1
+ * 1->1->1 becomes .......
+ *
+ */
+u8_t
+pbuf_free(struct pbuf *p)
+{
+  u16_t type;
+  struct pbuf *q;
+  u8_t count;
+
+  if (p == NULL) {
+    LWIP_ASSERT("p != NULL", p != NULL);
+    /* if assertions are disabled, proceed with debug output */
+    LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
+      ("pbuf_free(p == NULL) was called.\n"));
+    return 0;
+  }
+  LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_free(%p)\n", (void *)p));
+
+  PERF_START;
+
+  LWIP_ASSERT("pbuf_free: sane type",
+    p->type == PBUF_RAM || p->type == PBUF_ROM ||
+    p->type == PBUF_REF || p->type == PBUF_POOL);
+
+  count = 0;
+  /* de-allocate all consecutive pbufs from the head of the chain that
+   * obtain a zero reference count after decrementing*/
+  while (p != NULL) {
+    u16_t ref;
+    SYS_ARCH_DECL_PROTECT(old_level);
+    /* Since decrementing ref cannot be guaranteed to be a single machine operation
+     * we must protect it. We put the new ref into a local variable to prevent
+     * further protection. */
+    SYS_ARCH_PROTECT(old_level);
+    /* all pbufs in a chain are referenced at least once */
+    LWIP_ASSERT("pbuf_free: p->ref > 0", p->ref > 0);
+    /* decrease reference count (number of pointers to pbuf) */
+    ref = --(p->ref);
+    SYS_ARCH_UNPROTECT(old_level);
+    /* this pbuf is no longer referenced to? */
+    if (ref == 0) {
+      /* remember next pbuf in chain for next iteration */
+      q = p->next;
+      LWIP_DEBUGF( PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_free: deallocating %p\n", (void *)p));
+      type = p->type;
+#if LWIP_SUPPORT_CUSTOM_PBUF
+      /* is this a custom pbuf? */
+      if ((p->flags & PBUF_FLAG_IS_CUSTOM) != 0) {
+        struct pbuf_custom *pc = (struct pbuf_custom*)p;
+        LWIP_ASSERT("pc->custom_free_function != NULL", pc->custom_free_function != NULL);
+        pc->custom_free_function(p);
+      } else
+#endif /* LWIP_SUPPORT_CUSTOM_PBUF */
+      {
+        /* is this a pbuf from the pool? */
+        if (type == PBUF_POOL) {
+          memp_free(MEMP_PBUF_POOL, p);
+        /* is this a ROM or RAM referencing pbuf? */
+        } else if (type == PBUF_ROM || type == PBUF_REF) {
+          memp_free(MEMP_PBUF, p);
+        /* type == PBUF_RAM */
+        } else {
+          mem_free(p);
+        }
+      }
+      count++;
+      /* proceed to next pbuf */
+      p = q;
+    /* p->ref > 0, this pbuf is still referenced to */
+    /* (and so the remaining pbufs in chain as well) */
+    } else {
+      LWIP_DEBUGF( PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_free: %p has ref %"U16_F", ending here.\n", (void *)p, ref));
+      /* stop walking through the chain */
+      p = NULL;
+    }
+  }
+  PERF_STOP("pbuf_free");
+  /* return number of de-allocated pbufs */
+  return count;
+}
+
+/**
+ * Count number of pbufs in a chain
+ *
+ * @param p first pbuf of chain
+ * @return the number of pbufs in a chain
+ */
+
+u8_t
+pbuf_clen(struct pbuf *p)
+{
+  u8_t len;
+
+  len = 0;
+  while (p != NULL) {
+    ++len;
+    p = p->next;
+  }
+  return len;
+}
+
+/**
+ * Increment the reference count of the pbuf.
+ *
+ * @param p pbuf to increase reference counter of
+ *
+ */
+void
+pbuf_ref(struct pbuf *p)
+{
+  SYS_ARCH_DECL_PROTECT(old_level);
+  /* pbuf given? */
+  if (p != NULL) {
+    SYS_ARCH_PROTECT(old_level);
+    ++(p->ref);
+    SYS_ARCH_UNPROTECT(old_level);
+  }
+}
+
+/**
+ * Concatenate two pbufs (each may be a pbuf chain) and take over
+ * the caller's reference of the tail pbuf.
+ * 
+ * @note The caller MAY NOT reference the tail pbuf afterwards.
+ * Use pbuf_chain() for that purpose.
+ * 
+ * @see pbuf_chain()
+ */
+
+void
+pbuf_cat(struct pbuf *h, struct pbuf *t)
+{
+  struct pbuf *p;
+
+  LWIP_ERROR("(h != NULL) && (t != NULL) (programmer violates API)",
+             ((h != NULL) && (t != NULL)), return;);
+
+  /* proceed to last pbuf of chain */
+  for (p = h; p->next != NULL; p = p->next) {
+    /* add total length of second chain to all totals of first chain */
+    p->tot_len += t->tot_len;
+  }
+  /* { p is last pbuf of first h chain, p->next == NULL } */
+  LWIP_ASSERT("p->tot_len == p->len (of last pbuf in chain)", p->tot_len == p->len);
+  LWIP_ASSERT("p->next == NULL", p->next == NULL);
+  /* add total length of second chain to last pbuf total of first chain */
+  p->tot_len += t->tot_len;
+  /* chain last pbuf of head (p) with first of tail (t) */
+  p->next = t;
+  /* p->next now references t, but the caller will drop its reference to t,
+   * so netto there is no change to the reference count of t.
+   */
+}
+
+/**
+ * Chain two pbufs (or pbuf chains) together.
+ * 
+ * The caller MUST call pbuf_free(t) once it has stopped
+ * using it. Use pbuf_cat() instead if you no longer use t.
+ * 
+ * @param h head pbuf (chain)
+ * @param t tail pbuf (chain)
+ * @note The pbufs MUST belong to the same packet.
+ * @note MAY NOT be called on a packet queue.
+ *
+ * The ->tot_len fields of all pbufs of the head chain are adjusted.
+ * The ->next field of the last pbuf of the head chain is adjusted.
+ * The ->ref field of the first pbuf of the tail chain is adjusted.
+ *
+ */
+void
+pbuf_chain(struct pbuf *h, struct pbuf *t)
+{
+  pbuf_cat(h, t);
+  /* t is now referenced by h */
+  pbuf_ref(t);
+  LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_chain: %p references %p\n", (void *)h, (void *)t));
+}
+
+/**
+ * Dechains the first pbuf from its succeeding pbufs in the chain.
+ *
+ * Makes p->tot_len field equal to p->len.
+ * @param p pbuf to dechain
+ * @return remainder of the pbuf chain, or NULL if it was de-allocated.
+ * @note May not be called on a packet queue.
+ */
+struct pbuf *
+pbuf_dechain(struct pbuf *p)
+{
+  struct pbuf *q;
+  u8_t tail_gone = 1;
+  /* tail */
+  q = p->next;
+  /* pbuf has successor in chain? */
+  if (q != NULL) {
+    /* assert tot_len invariant: (p->tot_len == p->len + (p->next? p->next->tot_len: 0) */
+    LWIP_ASSERT("p->tot_len == p->len + q->tot_len", q->tot_len == p->tot_len - p->len);
+    /* enforce invariant if assertion is disabled */
+    q->tot_len = p->tot_len - p->len;
+    /* decouple pbuf from remainder */
+    p->next = NULL;
+    /* total length of pbuf p is its own length only */
+    p->tot_len = p->len;
+    /* q is no longer referenced by p, free it */
+    LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_dechain: unreferencing %p\n", (void *)q));
+    tail_gone = pbuf_free(q);
+    if (tail_gone > 0) {
+      LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE,
+                  ("pbuf_dechain: deallocated %p (as it is no longer referenced)\n", (void *)q));
+    }
+    /* return remaining tail or NULL if deallocated */
+  }
+  /* assert tot_len invariant: (p->tot_len == p->len + (p->next? p->next->tot_len: 0) */
+  LWIP_ASSERT("p->tot_len == p->len", p->tot_len == p->len);
+  return ((tail_gone > 0) ? NULL : q);
+}
+
+/**
+ *
+ * Create PBUF_RAM copies of pbufs.
+ *
+ * Used to queue packets on behalf of the lwIP stack, such as
+ * ARP based queueing.
+ *
+ * @note You MUST explicitly use p = pbuf_take(p);
+ *
+ * @note Only one packet is copied, no packet queue!
+ *
+ * @param p_to pbuf destination of the copy
+ * @param p_from pbuf source of the copy
+ *
+ * @return ERR_OK if pbuf was copied
+ *         ERR_ARG if one of the pbufs is NULL or p_to is not big
+ *                 enough to hold p_from
+ */
+err_t
+pbuf_copy(struct pbuf *p_to, struct pbuf *p_from)
+{
+  u16_t offset_to=0, offset_from=0, len;
+
+  LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_copy(%p, %p)\n",
+    (void*)p_to, (void*)p_from));
+
+  /* is the target big enough to hold the source? */
+  LWIP_ERROR("pbuf_copy: target not big enough to hold source", ((p_to != NULL) &&
+             (p_from != NULL) && (p_to->tot_len >= p_from->tot_len)), return ERR_ARG;);
+
+  /* iterate through pbuf chain */
+  do
+  {
+    LWIP_ASSERT("p_to != NULL", p_to != NULL);
+    /* copy one part of the original chain */
+    if ((p_to->len - offset_to) >= (p_from->len - offset_from)) {
+      /* complete current p_from fits into current p_to */
+      len = p_from->len - offset_from;
+    } else {
+      /* current p_from does not fit into current p_to */
+      len = p_to->len - offset_to;
+    }
+    MEMCPY((u8_t*)p_to->payload + offset_to, (u8_t*)p_from->payload + offset_from, len);
+    offset_to += len;
+    offset_from += len;
+    LWIP_ASSERT("offset_to <= p_to->len", offset_to <= p_to->len);
+    if (offset_to == p_to->len) {
+      /* on to next p_to (if any) */
+      offset_to = 0;
+      p_to = p_to->next;
+    }
+    LWIP_ASSERT("offset_from <= p_from->len", offset_from <= p_from->len);
+    if (offset_from >= p_from->len) {
+      /* on to next p_from (if any) */
+      offset_from = 0;
+      p_from = p_from->next;
+    }
+
+    if((p_from != NULL) && (p_from->len == p_from->tot_len)) {
+      /* don't copy more than one packet! */
+      LWIP_ERROR("pbuf_copy() does not allow packet queues!\n",
+                 (p_from->next == NULL), return ERR_VAL;);
+    }
+    if((p_to != NULL) && (p_to->len == p_to->tot_len)) {
+      /* don't copy more than one packet! */
+      LWIP_ERROR("pbuf_copy() does not allow packet queues!\n",
+                  (p_to->next == NULL), return ERR_VAL;);
+    }
+  } while (p_from);
+  LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_copy: end of chain reached.\n"));
+  return ERR_OK;
+}
+
+/**
+ * Copy (part of) the contents of a packet buffer
+ * to an application supplied buffer.
+ *
+ * @param buf the pbuf from which to copy data
+ * @param dataptr the application supplied buffer
+ * @param len length of data to copy (dataptr must be big enough). No more 
+ * than buf->tot_len will be copied, irrespective of len
+ * @param offset offset into the packet buffer from where to begin copying len bytes
+ * @return the number of bytes copied, or 0 on failure
+ */
+u16_t
+pbuf_copy_partial(struct pbuf *buf, void *dataptr, u16_t len, u16_t offset)
+{
+  struct pbuf *p;
+  u16_t left;
+  u16_t buf_copy_len;
+  u16_t copied_total = 0;
+
+  LWIP_ERROR("pbuf_copy_partial: invalid buf", (buf != NULL), return 0;);
+  LWIP_ERROR("pbuf_copy_partial: invalid dataptr", (dataptr != NULL), return 0;);
+
+  left = 0;
+
+  if((buf == NULL) || (dataptr == NULL)) {
+    return 0;
+  }
+
+  /* Note some systems use byte copy if dataptr or one of the pbuf payload pointers are unaligned. */
+  for(p = buf; len != 0 && p != NULL; p = p->next) {
+    if ((offset != 0) && (offset >= p->len)) {
+      /* don't copy from this buffer -> on to the next */
+      offset -= p->len;
+    } else {
+      /* copy from this buffer. maybe only partially. */
+      buf_copy_len = p->len - offset;
+      if (buf_copy_len > len)
+          buf_copy_len = len;
+      /* copy the necessary parts of the buffer */
+      MEMCPY(&((char*)dataptr)[left], &((char*)p->payload)[offset], buf_copy_len);
+      copied_total += buf_copy_len;
+      left += buf_copy_len;
+      len -= buf_copy_len;
+      offset = 0;
+    }
+  }
+  return copied_total;
+}
+
+/**
+ * Copy application supplied data into a pbuf.
+ * This function can only be used to copy the equivalent of buf->tot_len data.
+ *
+ * @param buf pbuf to fill with data
+ * @param dataptr application supplied data buffer
+ * @param len length of the application supplied data buffer
+ *
+ * @return ERR_OK if successful, ERR_MEM if the pbuf is not big enough
+ */
+err_t
+pbuf_take(struct pbuf *buf, const void *dataptr, u16_t len)
+{
+  struct pbuf *p;
+  u16_t buf_copy_len;
+  u16_t total_copy_len = len;
+  u16_t copied_total = 0;
+
+  LWIP_ERROR("pbuf_take: invalid buf", (buf != NULL), return 0;);
+  LWIP_ERROR("pbuf_take: invalid dataptr", (dataptr != NULL), return 0;);
+
+  if ((buf == NULL) || (dataptr == NULL) || (buf->tot_len < len)) {
+    return ERR_ARG;
+  }
+
+  /* Note some systems use byte copy if dataptr or one of the pbuf payload pointers are unaligned. */
+  for(p = buf; total_copy_len != 0; p = p->next) {
+    LWIP_ASSERT("pbuf_take: invalid pbuf", p != NULL);
+    buf_copy_len = total_copy_len;
+    if (buf_copy_len > p->len) {
+      /* this pbuf cannot hold all remaining data */
+      buf_copy_len = p->len;
+    }
+    /* copy the necessary parts of the buffer */
+    MEMCPY(p->payload, &((char*)dataptr)[copied_total], buf_copy_len);
+    total_copy_len -= buf_copy_len;
+    copied_total += buf_copy_len;
+  }
+  LWIP_ASSERT("did not copy all data", total_copy_len == 0 && copied_total == len);
+  return ERR_OK;
+}
+
+/**
+ * Creates a single pbuf out of a queue of pbufs.
+ *
+ * @remark: Either the source pbuf 'p' is freed by this function or the original
+ *          pbuf 'p' is returned, therefore the caller has to check the result!
+ *
+ * @param p the source pbuf
+ * @param layer pbuf_layer of the new pbuf
+ *
+ * @return a new, single pbuf (p->next is NULL)
+ *         or the old pbuf if allocation fails
+ */
+struct pbuf*
+pbuf_coalesce(struct pbuf *p, pbuf_layer layer)
+{
+  struct pbuf *q;
+  err_t err;
+  if (p->next == NULL) {
+    return p;
+  }
+  q = pbuf_alloc(layer, p->tot_len, PBUF_RAM);
+  if (q == NULL) {
+    /* @todo: what do we do now? */
+    return p;
+  }
+  err = pbuf_copy(q, p);
+  LWIP_ASSERT("pbuf_copy failed", err == ERR_OK);
+  pbuf_free(p);
+  return q;
+}
+
+#if LWIP_CHECKSUM_ON_COPY
+/**
+ * Copies data into a single pbuf (*not* into a pbuf queue!) and updates
+ * the checksum while copying
+ *
+ * @param p the pbuf to copy data into
+ * @param start_offset offset of p->payload where to copy the data to
+ * @param dataptr data to copy into the pbuf
+ * @param len length of data to copy into the pbuf
+ * @param chksum pointer to the checksum which is updated
+ * @return ERR_OK if successful, another error if the data does not fit
+ *         within the (first) pbuf (no pbuf queues!)
+ */
+err_t
+pbuf_fill_chksum(struct pbuf *p, u16_t start_offset, const void *dataptr,
+                 u16_t len, u16_t *chksum)
+{
+  u32_t acc;
+  u16_t copy_chksum;
+  char *dst_ptr;
+  LWIP_ASSERT("p != NULL", p != NULL);
+  LWIP_ASSERT("dataptr != NULL", dataptr != NULL);
+  LWIP_ASSERT("chksum != NULL", chksum != NULL);
+  LWIP_ASSERT("len != 0", len != 0);
+
+  if ((start_offset >= p->len) || (start_offset + len > p->len)) {
+    return ERR_ARG;
+  }
+
+  dst_ptr = ((char*)p->payload) + start_offset;
+  copy_chksum = LWIP_CHKSUM_COPY(dst_ptr, dataptr, len);
+  if ((start_offset & 1) != 0) {
+    copy_chksum = SWAP_BYTES_IN_WORD(copy_chksum);
+  }
+  acc = *chksum;
+  acc += copy_chksum;
+  *chksum = FOLD_U32T(acc);
+  return ERR_OK;
+}
+#endif /* LWIP_CHECKSUM_ON_COPY */
+
+ /** Get one byte from the specified position in a pbuf
+ * WARNING: returns zero for offset >= p->tot_len
+ *
+ * @param p pbuf to parse
+ * @param offset offset into p of the byte to return
+ * @return byte at an offset into p OR ZERO IF 'offset' >= p->tot_len
+ */
+u8_t
+pbuf_get_at(struct pbuf* p, u16_t offset)
+{
+  u16_t copy_from = offset;
+  struct pbuf* q = p;
+
+  /* get the correct pbuf */
+  while ((q != NULL) && (q->len <= copy_from)) {
+    copy_from -= q->len;
+    q = q->next;
+  }
+  /* return requested data if pbuf is OK */
+  if ((q != NULL) && (q->len > copy_from)) {
+    return ((u8_t*)q->payload)[copy_from];
+  }
+  return 0;
+}
+
+/** Compare pbuf contents at specified offset with memory s2, both of length n
+ *
+ * @param p pbuf to compare
+ * @param offset offset into p at wich to start comparing
+ * @param s2 buffer to compare
+ * @param n length of buffer to compare
+ * @return zero if equal, nonzero otherwise
+ *         (0xffff if p is too short, diffoffset+1 otherwise)
+ */
+u16_t
+pbuf_memcmp(struct pbuf* p, u16_t offset, const void* s2, u16_t n)
+{
+  u16_t start = offset;
+  struct pbuf* q = p;
+
+  /* get the correct pbuf */
+  while ((q != NULL) && (q->len <= start)) {
+    start -= q->len;
+    q = q->next;
+  }
+  /* return requested data if pbuf is OK */
+  if ((q != NULL) && (q->len > start)) {
+    u16_t i;
+    for(i = 0; i < n; i++) {
+      u8_t a = pbuf_get_at(q, start + i);
+      u8_t b = ((u8_t*)s2)[i];
+      if (a != b) {
+        return i+1;
+      }
+    }
+    return 0;
+  }
+  return 0xffff;
+}
+
+/** Find occurrence of mem (with length mem_len) in pbuf p, starting at offset
+ * start_offset.
+ *
+ * @param p pbuf to search, maximum length is 0xFFFE since 0xFFFF is used as
+ *        return value 'not found'
+ * @param mem search for the contents of this buffer
+ * @param mem_len length of 'mem'
+ * @param start_offset offset into p at which to start searching
+ * @return 0xFFFF if substr was not found in p or the index where it was found
+ */
+u16_t
+pbuf_memfind(struct pbuf* p, const void* mem, u16_t mem_len, u16_t start_offset)
+{
+  u16_t i;
+  u16_t max = p->tot_len - mem_len;
+  if (p->tot_len >= mem_len + start_offset) {
+    for(i = start_offset; i <= max; ) {
+      u16_t plus = pbuf_memcmp(p, i, mem, mem_len);
+      if (plus == 0) {
+        return i;
+      } else {
+        i += plus;
+      }
+    }
+  }
+  return 0xFFFF;
+}
+
+/** Find occurrence of substr with length substr_len in pbuf p, start at offset
+ * start_offset
+ * WARNING: in contrast to strstr(), this one does not stop at the first \0 in
+ * the pbuf/source string!
+ *
+ * @param p pbuf to search, maximum length is 0xFFFE since 0xFFFF is used as
+ *        return value 'not found'
+ * @param substr string to search for in p, maximum length is 0xFFFE
+ * @return 0xFFFF if substr was not found in p or the index where it was found
+ */
+u16_t
+pbuf_strstr(struct pbuf* p, const char* substr)
+{
+  size_t substr_len;
+  if ((substr == NULL) || (substr[0] == 0) || (p->tot_len == 0xFFFF)) {
+    return 0xFFFF;
+  }
+  substr_len = strlen(substr);
+  if (substr_len >= 0xFFFF) {
+    return 0xFFFF;
+  }
+  return pbuf_memfind(p, substr, (u16_t)substr_len, 0);
+}
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/core/stats.c	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,176 @@
+/**
+ * @file
+ * Statistics module
+ *
+ */
+
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+
+#include "lwip/opt.h"
+
+#if LWIP_STATS /* don't build if not configured for use in lwipopts.h */
+
+#include "lwip/def.h"
+#include "lwip/stats.h"
+#include "lwip/mem.h"
+
+#include <string.h>
+
+struct stats_ lwip_stats;
+
+void stats_init(void)
+{
+#ifdef LWIP_DEBUG
+#if MEMP_STATS
+  const char * memp_names[] = {
+#define LWIP_MEMPOOL(name,num,size,desc) desc,
+#include "lwip/memp_std.h"
+  };
+  int i;
+  for (i = 0; i < MEMP_MAX; i++) {
+    lwip_stats.memp[i].name = memp_names[i];
+  }
+#endif /* MEMP_STATS */
+#if MEM_STATS
+  lwip_stats.mem.name = "MEM";
+#endif /* MEM_STATS */
+#endif /* LWIP_DEBUG */
+}
+
+#if LWIP_STATS_DISPLAY
+void
+stats_display_proto(struct stats_proto *proto, char *name)
+{
+  LWIP_PLATFORM_DIAG(("\n%s\n\t", name));
+  LWIP_PLATFORM_DIAG(("xmit: %"STAT_COUNTER_F"\n\t", proto->xmit)); 
+  LWIP_PLATFORM_DIAG(("recv: %"STAT_COUNTER_F"\n\t", proto->recv)); 
+  LWIP_PLATFORM_DIAG(("fw: %"STAT_COUNTER_F"\n\t", proto->fw)); 
+  LWIP_PLATFORM_DIAG(("drop: %"STAT_COUNTER_F"\n\t", proto->drop)); 
+  LWIP_PLATFORM_DIAG(("chkerr: %"STAT_COUNTER_F"\n\t", proto->chkerr)); 
+  LWIP_PLATFORM_DIAG(("lenerr: %"STAT_COUNTER_F"\n\t", proto->lenerr)); 
+  LWIP_PLATFORM_DIAG(("memerr: %"STAT_COUNTER_F"\n\t", proto->memerr)); 
+  LWIP_PLATFORM_DIAG(("rterr: %"STAT_COUNTER_F"\n\t", proto->rterr)); 
+  LWIP_PLATFORM_DIAG(("proterr: %"STAT_COUNTER_F"\n\t", proto->proterr)); 
+  LWIP_PLATFORM_DIAG(("opterr: %"STAT_COUNTER_F"\n\t", proto->opterr)); 
+  LWIP_PLATFORM_DIAG(("err: %"STAT_COUNTER_F"\n\t", proto->err)); 
+  LWIP_PLATFORM_DIAG(("cachehit: %"STAT_COUNTER_F"\n", proto->cachehit)); 
+}
+
+#if IGMP_STATS
+void
+stats_display_igmp(struct stats_igmp *igmp)
+{
+  LWIP_PLATFORM_DIAG(("\nIGMP\n\t"));
+  LWIP_PLATFORM_DIAG(("xmit: %"STAT_COUNTER_F"\n\t", igmp->xmit)); 
+  LWIP_PLATFORM_DIAG(("recv: %"STAT_COUNTER_F"\n\t", igmp->recv)); 
+  LWIP_PLATFORM_DIAG(("drop: %"STAT_COUNTER_F"\n\t", igmp->drop)); 
+  LWIP_PLATFORM_DIAG(("chkerr: %"STAT_COUNTER_F"\n\t", igmp->chkerr)); 
+  LWIP_PLATFORM_DIAG(("lenerr: %"STAT_COUNTER_F"\n\t", igmp->lenerr)); 
+  LWIP_PLATFORM_DIAG(("memerr: %"STAT_COUNTER_F"\n\t", igmp->memerr)); 
+  LWIP_PLATFORM_DIAG(("proterr: %"STAT_COUNTER_F"\n\t", igmp->proterr)); 
+  LWIP_PLATFORM_DIAG(("rx_v1: %"STAT_COUNTER_F"\n\t", igmp->rx_v1)); 
+  LWIP_PLATFORM_DIAG(("rx_group: %"STAT_COUNTER_F"\n", igmp->rx_group));
+  LWIP_PLATFORM_DIAG(("rx_general: %"STAT_COUNTER_F"\n", igmp->rx_general));
+  LWIP_PLATFORM_DIAG(("rx_report: %"STAT_COUNTER_F"\n\t", igmp->rx_report)); 
+  LWIP_PLATFORM_DIAG(("tx_join: %"STAT_COUNTER_F"\n\t", igmp->tx_join)); 
+  LWIP_PLATFORM_DIAG(("tx_leave: %"STAT_COUNTER_F"\n\t", igmp->tx_leave)); 
+  LWIP_PLATFORM_DIAG(("tx_report: %"STAT_COUNTER_F"\n\t", igmp->tx_report)); 
+}
+#endif /* IGMP_STATS */
+
+#if MEM_STATS || MEMP_STATS
+void
+stats_display_mem(struct stats_mem *mem, char *name)
+{
+  LWIP_PLATFORM_DIAG(("\nMEM %s\n\t", name));
+  LWIP_PLATFORM_DIAG(("avail: %"U32_F"\n\t", (u32_t)mem->avail)); 
+  LWIP_PLATFORM_DIAG(("used: %"U32_F"\n\t", (u32_t)mem->used)); 
+  LWIP_PLATFORM_DIAG(("max: %"U32_F"\n\t", (u32_t)mem->max)); 
+  LWIP_PLATFORM_DIAG(("err: %"U32_F"\n", (u32_t)mem->err));
+}
+
+#if MEMP_STATS
+void
+stats_display_memp(struct stats_mem *mem, int index)
+{
+  char * memp_names[] = {
+#define LWIP_MEMPOOL(name,num,size,desc) desc,
+#include "lwip/memp_std.h"
+  };
+  if(index < MEMP_MAX) {
+    stats_display_mem(mem, memp_names[index]);
+  }
+}
+#endif /* MEMP_STATS */
+#endif /* MEM_STATS || MEMP_STATS */
+
+#if SYS_STATS
+void
+stats_display_sys(struct stats_sys *sys)
+{
+  LWIP_PLATFORM_DIAG(("\nSYS\n\t"));
+  LWIP_PLATFORM_DIAG(("sem.used:  %"U32_F"\n\t", (u32_t)sys->sem.used)); 
+  LWIP_PLATFORM_DIAG(("sem.max:   %"U32_F"\n\t", (u32_t)sys->sem.max)); 
+  LWIP_PLATFORM_DIAG(("sem.err:   %"U32_F"\n\t", (u32_t)sys->sem.err)); 
+  LWIP_PLATFORM_DIAG(("mutex.used: %"U32_F"\n\t", (u32_t)sys->mutex.used)); 
+  LWIP_PLATFORM_DIAG(("mutex.max:  %"U32_F"\n\t", (u32_t)sys->mutex.max)); 
+  LWIP_PLATFORM_DIAG(("mutex.err:  %"U32_F"\n\t", (u32_t)sys->mutex.err)); 
+  LWIP_PLATFORM_DIAG(("mbox.used:  %"U32_F"\n\t", (u32_t)sys->mbox.used)); 
+  LWIP_PLATFORM_DIAG(("mbox.max:   %"U32_F"\n\t", (u32_t)sys->mbox.max)); 
+  LWIP_PLATFORM_DIAG(("mbox.err:   %"U32_F"\n\t", (u32_t)sys->mbox.err)); 
+}
+#endif /* SYS_STATS */
+
+void
+stats_display(void)
+{
+  s16_t i;
+
+  LINK_STATS_DISPLAY();
+  ETHARP_STATS_DISPLAY();
+  IPFRAG_STATS_DISPLAY();
+  IP_STATS_DISPLAY();
+  IGMP_STATS_DISPLAY();
+  ICMP_STATS_DISPLAY();
+  UDP_STATS_DISPLAY();
+  TCP_STATS_DISPLAY();
+  MEM_STATS_DISPLAY();
+  for (i = 0; i < MEMP_MAX; i++) {
+    MEMP_STATS_DISPLAY(i);
+  }
+  SYS_STATS_DISPLAY();
+}
+#endif /* LWIP_STATS_DISPLAY */
+
+#endif /* LWIP_STATS */
+
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/core/sys.c	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,66 @@
+/**
+ * @file
+ * lwIP Operating System abstraction
+ *
+ */
+
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ *
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+
+#include "lwip/opt.h"
+
+#include "lwip/sys.h"
+
+/* Most of the functions defined in sys.h must be implemented in the
+ * architecture-dependent file sys_arch.c */
+
+#if !NO_SYS
+
+/**
+ * Sleep for some ms. Timeouts are NOT processed while sleeping.
+ *
+ * @param ms number of milliseconds to sleep
+ */
+void
+sys_msleep(u32_t ms)
+{
+  if (ms > 0) {
+    sys_sem_t delaysem;
+    err_t err = sys_sem_new(&delaysem, 0);
+    if (err == ERR_OK) {
+      sys_arch_sem_wait(&delaysem, ms);
+      sys_sem_free(&delaysem);
+    }
+  }
+}
+
+#endif /* !NO_SYS */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/core/tcp.c	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,1631 @@
+/**
+ * @file
+ * Transmission Control Protocol for IP
+ *
+ * This file contains common functions for the TCP implementation, such as functinos
+ * for manipulating the data structures and the TCP timer functions. TCP functions
+ * related to input and output is found in tcp_in.c and tcp_out.c respectively.
+ *
+ */
+
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+
+#include "lwip/opt.h"
+
+#if LWIP_TCP /* don't build if not configured for use in lwipopts.h */
+
+#include "lwip/def.h"
+#include "lwip/mem.h"
+#include "lwip/memp.h"
+#include "lwip/snmp.h"
+#include "lwip/tcp.h"
+#include "lwip/tcp_impl.h"
+#include "lwip/debug.h"
+#include "lwip/stats.h"
+
+#include <string.h>
+
+const char * const tcp_state_str[] = {
+  "CLOSED",      
+  "LISTEN",      
+  "SYN_SENT",    
+  "SYN_RCVD",    
+  "ESTABLISHED", 
+  "FIN_WAIT_1",  
+  "FIN_WAIT_2",  
+  "CLOSE_WAIT",  
+  "CLOSING",     
+  "LAST_ACK",    
+  "TIME_WAIT"   
+};
+
+/* Incremented every coarse grained timer shot (typically every 500 ms). */
+u32_t tcp_ticks;
+const u8_t tcp_backoff[13] =
+    { 1, 2, 3, 4, 5, 6, 7, 7, 7, 7, 7, 7, 7};
+ /* Times per slowtmr hits */
+const u8_t tcp_persist_backoff[7] = { 3, 6, 12, 24, 48, 96, 120 };
+
+/* The TCP PCB lists. */
+
+/** List of all TCP PCBs bound but not yet (connected || listening) */
+struct tcp_pcb *tcp_bound_pcbs;
+/** List of all TCP PCBs in LISTEN state */
+union tcp_listen_pcbs_t tcp_listen_pcbs;
+/** List of all TCP PCBs that are in a state in which
+ * they accept or send data. */
+struct tcp_pcb *tcp_active_pcbs;
+/** List of all TCP PCBs in TIME-WAIT state */
+struct tcp_pcb *tcp_tw_pcbs;
+
+#define NUM_TCP_PCB_LISTS               4
+#define NUM_TCP_PCB_LISTS_NO_TIME_WAIT  3
+/** An array with all (non-temporary) PCB lists, mainly used for smaller code size */
+struct tcp_pcb **tcp_pcb_lists[] = {&tcp_listen_pcbs.pcbs, &tcp_bound_pcbs,
+  &tcp_active_pcbs, &tcp_tw_pcbs};
+
+/** Only used for temporary storage. */
+struct tcp_pcb *tcp_tmp_pcb;
+
+/** Timer counter to handle calling slow-timer from tcp_tmr() */ 
+static u8_t tcp_timer;
+static u16_t tcp_new_port(void);
+
+/**
+ * Called periodically to dispatch TCP timers.
+ *
+ */
+void
+tcp_tmr(void)
+{
+  /* Call tcp_fasttmr() every 250 ms */
+  tcp_fasttmr();
+
+  if (++tcp_timer & 1) {
+    /* Call tcp_tmr() every 500 ms, i.e., every other timer
+       tcp_tmr() is called. */
+    tcp_slowtmr();
+  }
+}
+
+/**
+ * Closes the TX side of a connection held by the PCB.
+ * For tcp_close(), a RST is sent if the application didn't receive all data
+ * (tcp_recved() not called for all data passed to recv callback).
+ *
+ * Listening pcbs are freed and may not be referenced any more.
+ * Connection pcbs are freed if not yet connected and may not be referenced
+ * any more. If a connection is established (at least SYN received or in
+ * a closing state), the connection is closed, and put in a closing state.
+ * The pcb is then automatically freed in tcp_slowtmr(). It is therefore
+ * unsafe to reference it.
+ *
+ * @param pcb the tcp_pcb to close
+ * @return ERR_OK if connection has been closed
+ *         another err_t if closing failed and pcb is not freed
+ */
+static err_t
+tcp_close_shutdown(struct tcp_pcb *pcb, u8_t rst_on_unacked_data)
+{
+  err_t err;
+
+  if (rst_on_unacked_data && (pcb->state != LISTEN)) {
+    if ((pcb->refused_data != NULL) || (pcb->rcv_wnd != TCP_WND)) {
+      /* Not all data received by application, send RST to tell the remote
+         side about this. */
+      LWIP_ASSERT("pcb->flags & TF_RXCLOSED", pcb->flags & TF_RXCLOSED);
+
+      /* don't call tcp_abort here: we must not deallocate the pcb since
+         that might not be expected when calling tcp_close */
+      tcp_rst(pcb->snd_nxt, pcb->rcv_nxt, &pcb->local_ip, &pcb->remote_ip,
+        pcb->local_port, pcb->remote_port);
+
+      tcp_pcb_purge(pcb);
+
+      /* TODO: to which state do we move now? */
+
+      /* move to TIME_WAIT since we close actively */
+      TCP_RMV(&tcp_active_pcbs, pcb);
+      pcb->state = TIME_WAIT;
+      TCP_REG(&tcp_tw_pcbs, pcb);
+
+      return ERR_OK;
+    }
+  }
+
+  switch (pcb->state) {
+  case CLOSED:
+    /* Closing a pcb in the CLOSED state might seem erroneous,
+     * however, it is in this state once allocated and as yet unused
+     * and the user needs some way to free it should the need arise.
+     * Calling tcp_close() with a pcb that has already been closed, (i.e. twice)
+     * or for a pcb that has been used and then entered the CLOSED state 
+     * is erroneous, but this should never happen as the pcb has in those cases
+     * been freed, and so any remaining handles are bogus. */
+    err = ERR_OK;
+    TCP_RMV(&tcp_bound_pcbs, pcb);
+    memp_free(MEMP_TCP_PCB, pcb);
+    pcb = NULL;
+    break;
+  case LISTEN:
+    err = ERR_OK;
+    tcp_pcb_remove(&tcp_listen_pcbs.pcbs, pcb);
+    memp_free(MEMP_TCP_PCB_LISTEN, pcb);
+    pcb = NULL;
+    break;
+  case SYN_SENT:
+    err = ERR_OK;
+    tcp_pcb_remove(&tcp_active_pcbs, pcb);
+    memp_free(MEMP_TCP_PCB, pcb);
+    pcb = NULL;
+    snmp_inc_tcpattemptfails();
+    break;
+  case SYN_RCVD:
+    err = tcp_send_fin(pcb);
+    if (err == ERR_OK) {
+      snmp_inc_tcpattemptfails();
+      pcb->state = FIN_WAIT_1;
+    }
+    break;
+  case ESTABLISHED:
+    err = tcp_send_fin(pcb);
+    if (err == ERR_OK) {
+      snmp_inc_tcpestabresets();
+      pcb->state = FIN_WAIT_1;
+    }
+    break;
+  case CLOSE_WAIT:
+    err = tcp_send_fin(pcb);
+    if (err == ERR_OK) {
+      snmp_inc_tcpestabresets();
+      pcb->state = LAST_ACK;
+    }
+    break;
+  default:
+    /* Has already been closed, do nothing. */
+    err = ERR_OK;
+    pcb = NULL;
+    break;
+  }
+
+  if (pcb != NULL && err == ERR_OK) {
+    /* To ensure all data has been sent when tcp_close returns, we have
+       to make sure tcp_output doesn't fail.
+       Since we don't really have to ensure all data has been sent when tcp_close
+       returns (unsent data is sent from tcp timer functions, also), we don't care
+       for the return value of tcp_output for now. */
+    /* @todo: When implementing SO_LINGER, this must be changed somehow:
+       If SOF_LINGER is set, the data should be sent and acked before close returns.
+       This can only be valid for sequential APIs, not for the raw API. */
+    tcp_output(pcb);
+  }
+  return err;
+}
+
+/**
+ * Closes the connection held by the PCB.
+ *
+ * Listening pcbs are freed and may not be referenced any more.
+ * Connection pcbs are freed if not yet connected and may not be referenced
+ * any more. If a connection is established (at least SYN received or in
+ * a closing state), the connection is closed, and put in a closing state.
+ * The pcb is then automatically freed in tcp_slowtmr(). It is therefore
+ * unsafe to reference it (unless an error is returned).
+ *
+ * @param pcb the tcp_pcb to close
+ * @return ERR_OK if connection has been closed
+ *         another err_t if closing failed and pcb is not freed
+ */
+err_t
+tcp_close(struct tcp_pcb *pcb)
+{
+#if TCP_DEBUG
+  LWIP_DEBUGF(TCP_DEBUG, ("tcp_close: closing in "));
+  tcp_debug_print_state(pcb->state);
+#endif /* TCP_DEBUG */
+
+  if (pcb->state != LISTEN) {
+    /* Set a flag not to receive any more data... */
+    pcb->flags |= TF_RXCLOSED;
+  }
+  /* ... and close */
+  return tcp_close_shutdown(pcb, 1);
+}
+
+/**
+ * Causes all or part of a full-duplex connection of this PCB to be shut down.
+ * This doesn't deallocate the PCB!
+ *
+ * @param pcb PCB to shutdown
+ * @param shut_rx shut down receive side if this is != 0
+ * @param shut_tx shut down send side if this is != 0
+ * @return ERR_OK if shutdown succeeded (or the PCB has already been shut down)
+ *         another err_t on error.
+ */
+err_t
+tcp_shutdown(struct tcp_pcb *pcb, int shut_rx, int shut_tx)
+{
+  if (pcb->state == LISTEN) {
+    return ERR_CONN;
+  }
+  if (shut_rx) {
+    /* shut down the receive side: free buffered data... */
+    if (pcb->refused_data != NULL) {
+      pbuf_free(pcb->refused_data);
+      pcb->refused_data = NULL;
+    }
+    /* ... and set a flag not to receive any more data */
+    pcb->flags |= TF_RXCLOSED;
+  }
+  if (shut_tx) {
+    /* This can't happen twice since if it succeeds, the pcb's state is changed.
+       Only close in these states as the others directly deallocate the PCB */
+    switch (pcb->state) {
+  case SYN_RCVD:
+  case ESTABLISHED:
+  case CLOSE_WAIT:
+    return tcp_close_shutdown(pcb, 0);
+  default:
+    /* don't shut down other states */
+    break;
+    }
+  }
+  /* @todo: return another err_t if not in correct state or already shut? */
+  return ERR_OK;
+}
+
+/**
+ * Abandons a connection and optionally sends a RST to the remote
+ * host.  Deletes the local protocol control block. This is done when
+ * a connection is killed because of shortage of memory.
+ *
+ * @param pcb the tcp_pcb to abort
+ * @param reset boolean to indicate whether a reset should be sent
+ */
+void
+tcp_abandon(struct tcp_pcb *pcb, int reset)
+{
+  u32_t seqno, ackno;
+  u16_t remote_port, local_port;
+  ip_addr_t remote_ip, local_ip;
+#if LWIP_CALLBACK_API  
+  tcp_err_fn errf;
+#endif /* LWIP_CALLBACK_API */
+  void *errf_arg;
+
+  /* pcb->state LISTEN not allowed here */
+  LWIP_ASSERT("don't call tcp_abort/tcp_abandon for listen-pcbs",
+    pcb->state != LISTEN);
+  /* Figure out on which TCP PCB list we are, and remove us. If we
+     are in an active state, call the receive function associated with
+     the PCB with a NULL argument, and send an RST to the remote end. */
+  if (pcb->state == TIME_WAIT) {
+    tcp_pcb_remove(&tcp_tw_pcbs, pcb);
+    memp_free(MEMP_TCP_PCB, pcb);
+  } else {
+    seqno = pcb->snd_nxt;
+    ackno = pcb->rcv_nxt;
+    ip_addr_copy(local_ip, pcb->local_ip);
+    ip_addr_copy(remote_ip, pcb->remote_ip);
+    local_port = pcb->local_port;
+    remote_port = pcb->remote_port;
+#if LWIP_CALLBACK_API
+    errf = pcb->errf;
+#endif /* LWIP_CALLBACK_API */
+    errf_arg = pcb->callback_arg;
+    tcp_pcb_remove(&tcp_active_pcbs, pcb);
+    if (pcb->unacked != NULL) {
+      tcp_segs_free(pcb->unacked);
+    }
+    if (pcb->unsent != NULL) {
+      tcp_segs_free(pcb->unsent);
+    }
+#if TCP_QUEUE_OOSEQ    
+    if (pcb->ooseq != NULL) {
+      tcp_segs_free(pcb->ooseq);
+    }
+#endif /* TCP_QUEUE_OOSEQ */
+    memp_free(MEMP_TCP_PCB, pcb);
+    TCP_EVENT_ERR(errf, errf_arg, ERR_ABRT);
+    if (reset) {
+      LWIP_DEBUGF(TCP_RST_DEBUG, ("tcp_abandon: sending RST\n"));
+      tcp_rst(seqno, ackno, &local_ip, &remote_ip, local_port, remote_port);
+    }
+  }
+}
+
+/**
+ * Aborts the connection by sending a RST (reset) segment to the remote
+ * host. The pcb is deallocated. This function never fails.
+ *
+ * ATTENTION: When calling this from one of the TCP callbacks, make
+ * sure you always return ERR_ABRT (and never return ERR_ABRT otherwise
+ * or you will risk accessing deallocated memory or memory leaks!
+ *
+ * @param pcb the tcp pcb to abort
+ */
+void
+tcp_abort(struct tcp_pcb *pcb)
+{
+  tcp_abandon(pcb, 1);
+}
+
+/**
+ * Binds the connection to a local portnumber and IP address. If the
+ * IP address is not given (i.e., ipaddr == NULL), the IP address of
+ * the outgoing network interface is used instead.
+ *
+ * @param pcb the tcp_pcb to bind (no check is done whether this pcb is
+ *        already bound!)
+ * @param ipaddr the local ip address to bind to (use IP_ADDR_ANY to bind
+ *        to any local address
+ * @param port the local port to bind to
+ * @return ERR_USE if the port is already in use
+ *         ERR_OK if bound
+ */
+err_t
+tcp_bind(struct tcp_pcb *pcb, ip_addr_t *ipaddr, u16_t port)
+{
+  int i;
+  int max_pcb_list = NUM_TCP_PCB_LISTS;
+  struct tcp_pcb *cpcb;
+
+  LWIP_ERROR("tcp_bind: can only bind in state CLOSED", pcb->state == CLOSED, return ERR_ISCONN);
+
+#if SO_REUSE
+  /* Unless the REUSEADDR flag is set,
+     we have to check the pcbs in TIME-WAIT state, also.
+     We do not dump TIME_WAIT pcb's; they can still be matched by incoming
+     packets using both local and remote IP addresses and ports to distinguish.
+   */
+#if SO_REUSE
+  if ((pcb->so_options & SOF_REUSEADDR) != 0) {
+    max_pcb_list = NUM_TCP_PCB_LISTS_NO_TIME_WAIT;
+  }
+#endif /* SO_REUSE */
+#endif /* SO_REUSE */
+
+  if (port == 0) {
+    port = tcp_new_port();
+  }
+
+  /* Check if the address already is in use (on all lists) */
+  for (i = 0; i < max_pcb_list; i++) {
+    for(cpcb = *tcp_pcb_lists[i]; cpcb != NULL; cpcb = cpcb->next) {
+      if (cpcb->local_port == port) {
+#if SO_REUSE
+        /* Omit checking for the same port if both pcbs have REUSEADDR set.
+           For SO_REUSEADDR, the duplicate-check for a 5-tuple is done in
+           tcp_connect. */
+        if (((pcb->so_options & SOF_REUSEADDR) == 0) ||
+          ((cpcb->so_options & SOF_REUSEADDR) == 0))
+#endif /* SO_REUSE */
+        {
+          if (ip_addr_isany(&(cpcb->local_ip)) ||
+              ip_addr_isany(ipaddr) ||
+              ip_addr_cmp(&(cpcb->local_ip), ipaddr)) {
+            return ERR_USE;
+          }
+        }
+      }
+    }
+  }
+
+  if (!ip_addr_isany(ipaddr)) {
+    pcb->local_ip = *ipaddr;
+  }
+  pcb->local_port = port;
+  TCP_REG(&tcp_bound_pcbs, pcb);
+  LWIP_DEBUGF(TCP_DEBUG, ("tcp_bind: bind to port %"U16_F"\n", port));
+  return ERR_OK;
+}
+#if LWIP_CALLBACK_API
+/**
+ * Default accept callback if no accept callback is specified by the user.
+ */
+static err_t
+tcp_accept_null(void *arg, struct tcp_pcb *pcb, err_t err)
+{
+  LWIP_UNUSED_ARG(arg);
+  LWIP_UNUSED_ARG(pcb);
+  LWIP_UNUSED_ARG(err);
+
+  return ERR_ABRT;
+}
+#endif /* LWIP_CALLBACK_API */
+
+/**
+ * Set the state of the connection to be LISTEN, which means that it
+ * is able to accept incoming connections. The protocol control block
+ * is reallocated in order to consume less memory. Setting the
+ * connection to LISTEN is an irreversible process.
+ *
+ * @param pcb the original tcp_pcb
+ * @param backlog the incoming connections queue limit
+ * @return tcp_pcb used for listening, consumes less memory.
+ *
+ * @note The original tcp_pcb is freed. This function therefore has to be
+ *       called like this:
+ *             tpcb = tcp_listen(tpcb);
+ */
+struct tcp_pcb *
+tcp_listen_with_backlog(struct tcp_pcb *pcb, u8_t backlog)
+{
+  struct tcp_pcb_listen *lpcb;
+
+  LWIP_UNUSED_ARG(backlog);
+  LWIP_ERROR("tcp_listen: pcb already connected", pcb->state == CLOSED, return NULL);
+
+  /* already listening? */
+  if (pcb->state == LISTEN) {
+    return pcb;
+  }
+#if SO_REUSE
+  if ((pcb->so_options & SOF_REUSEADDR) != 0) {
+    /* Since SOF_REUSEADDR allows reusing a local address before the pcb's usage
+       is declared (listen-/connection-pcb), we have to make sure now that
+       this port is only used once for every local IP. */
+    for(lpcb = tcp_listen_pcbs.listen_pcbs; lpcb != NULL; lpcb = lpcb->next) {
+      if (lpcb->local_port == pcb->local_port) {
+        if (ip_addr_cmp(&lpcb->local_ip, &pcb->local_ip)) {
+          /* this address/port is already used */
+          return NULL;
+        }
+      }
+    }
+  }
+#endif /* SO_REUSE */
+  lpcb = (struct tcp_pcb_listen *)memp_malloc(MEMP_TCP_PCB_LISTEN);
+  if (lpcb == NULL) {
+    return NULL;
+  }
+  lpcb->callback_arg = pcb->callback_arg;
+  lpcb->local_port = pcb->local_port;
+  lpcb->state = LISTEN;
+  lpcb->prio = pcb->prio;
+  lpcb->so_options = pcb->so_options;
+  lpcb->so_options |= SOF_ACCEPTCONN;
+  lpcb->ttl = pcb->ttl;
+  lpcb->tos = pcb->tos;
+  ip_addr_copy(lpcb->local_ip, pcb->local_ip);
+  TCP_RMV(&tcp_bound_pcbs, pcb);
+  memp_free(MEMP_TCP_PCB, pcb);
+#if LWIP_CALLBACK_API
+  lpcb->accept = tcp_accept_null;
+#endif /* LWIP_CALLBACK_API */
+#if TCP_LISTEN_BACKLOG
+  lpcb->accepts_pending = 0;
+  lpcb->backlog = (backlog ? backlog : 1);
+#endif /* TCP_LISTEN_BACKLOG */
+  TCP_REG(&tcp_listen_pcbs.pcbs, (struct tcp_pcb *)lpcb);
+  return (struct tcp_pcb *)lpcb;
+}
+
+/** 
+ * Update the state that tracks the available window space to advertise.
+ *
+ * Returns how much extra window would be advertised if we sent an
+ * update now.
+ */
+u32_t tcp_update_rcv_ann_wnd(struct tcp_pcb *pcb)
+{
+  u32_t new_right_edge = pcb->rcv_nxt + pcb->rcv_wnd;
+
+  if (TCP_SEQ_GEQ(new_right_edge, pcb->rcv_ann_right_edge + LWIP_MIN((TCP_WND / 2), pcb->mss))) {
+    /* we can advertise more window */
+    pcb->rcv_ann_wnd = pcb->rcv_wnd;
+    return new_right_edge - pcb->rcv_ann_right_edge;
+  } else {
+    if (TCP_SEQ_GT(pcb->rcv_nxt, pcb->rcv_ann_right_edge)) {
+      /* Can happen due to other end sending out of advertised window,
+       * but within actual available (but not yet advertised) window */
+      pcb->rcv_ann_wnd = 0;
+    } else {
+      /* keep the right edge of window constant */
+      u32_t new_rcv_ann_wnd = pcb->rcv_ann_right_edge - pcb->rcv_nxt;
+      LWIP_ASSERT("new_rcv_ann_wnd <= 0xffff", new_rcv_ann_wnd <= 0xffff);
+      pcb->rcv_ann_wnd = (u16_t)new_rcv_ann_wnd;
+    }
+    return 0;
+  }
+}
+
+/**
+ * This function should be called by the application when it has
+ * processed the data. The purpose is to advertise a larger window
+ * when the data has been processed.
+ *
+ * @param pcb the tcp_pcb for which data is read
+ * @param len the amount of bytes that have been read by the application
+ */
+void
+tcp_recved(struct tcp_pcb *pcb, u16_t len)
+{
+  int wnd_inflation;
+
+  LWIP_ASSERT("tcp_recved: len would wrap rcv_wnd\n",
+              len <= 0xffff - pcb->rcv_wnd );
+
+  pcb->rcv_wnd += len;
+  if (pcb->rcv_wnd > TCP_WND) {
+    pcb->rcv_wnd = TCP_WND;
+  }
+
+  wnd_inflation = tcp_update_rcv_ann_wnd(pcb);
+
+  /* If the change in the right edge of window is significant (default
+   * watermark is TCP_WND/4), then send an explicit update now.
+   * Otherwise wait for a packet to be sent in the normal course of
+   * events (or more window to be available later) */
+  if (wnd_inflation >= TCP_WND_UPDATE_THRESHOLD) {
+    tcp_ack_now(pcb);
+    tcp_output(pcb);
+  }
+
+  LWIP_DEBUGF(TCP_DEBUG, ("tcp_recved: recveived %"U16_F" bytes, wnd %"U16_F" (%"U16_F").\n",
+         len, pcb->rcv_wnd, TCP_WND - pcb->rcv_wnd));
+}
+
+/**
+ * A nastly hack featuring 'goto' statements that allocates a
+ * new TCP local port.
+ *
+ * @return a new (free) local TCP port number
+ */
+static u16_t
+tcp_new_port(void)
+{
+  int i;
+  struct tcp_pcb *pcb;
+#ifndef TCP_LOCAL_PORT_RANGE_START
+#define TCP_LOCAL_PORT_RANGE_START 4096
+#define TCP_LOCAL_PORT_RANGE_END   0x7fff
+#endif
+  static u16_t port = TCP_LOCAL_PORT_RANGE_START;
+  
+ again:
+  if (++port > TCP_LOCAL_PORT_RANGE_END) {
+    port = TCP_LOCAL_PORT_RANGE_START;
+  }
+  /* Check all PCB lists. */
+  for (i = 1; i < NUM_TCP_PCB_LISTS; i++) {  
+    for(pcb = *tcp_pcb_lists[i]; pcb != NULL; pcb = pcb->next) {
+      if (pcb->local_port == port) {
+        goto again;
+      }
+    }
+  }
+  return port;
+}
+
+/**
+ * Connects to another host. The function given as the "connected"
+ * argument will be called when the connection has been established.
+ *
+ * @param pcb the tcp_pcb used to establish the connection
+ * @param ipaddr the remote ip address to connect to
+ * @param port the remote tcp port to connect to
+ * @param connected callback function to call when connected (or on error)
+ * @return ERR_VAL if invalid arguments are given
+ *         ERR_OK if connect request has been sent
+ *         other err_t values if connect request couldn't be sent
+ */
+err_t
+tcp_connect(struct tcp_pcb *pcb, ip_addr_t *ipaddr, u16_t port,
+      tcp_connected_fn connected)
+{
+  err_t ret;
+  u32_t iss;
+
+  LWIP_ERROR("tcp_connect: can only connected from state CLOSED", pcb->state == CLOSED, return ERR_ISCONN);
+
+  LWIP_DEBUGF(TCP_DEBUG, ("tcp_connect to port %"U16_F"\n", port));
+  if (ipaddr != NULL) {
+    pcb->remote_ip = *ipaddr;
+  } else {
+    return ERR_VAL;
+  }
+  pcb->remote_port = port;
+
+  /* check if we have a route to the remote host */
+  if (ip_addr_isany(&(pcb->local_ip))) {
+    /* no local IP address set, yet. */
+    struct netif *netif = ip_route(&(pcb->remote_ip));
+    if (netif == NULL) {
+      /* Don't even try to send a SYN packet if we have no route
+         since that will fail. */
+      return ERR_RTE;
+    }
+    /* Use the netif's IP address as local address. */
+    ip_addr_copy(pcb->local_ip, netif->ip_addr);
+  }
+
+  if (pcb->local_port == 0) {
+    pcb->local_port = tcp_new_port();
+  }
+#if SO_REUSE
+  if ((pcb->so_options & SOF_REUSEADDR) != 0) {
+    /* Since SOF_REUSEADDR allows reusing a local address, we have to make sure
+       now that the 5-tuple is unique. */
+    struct tcp_pcb *cpcb;
+    int i;
+    /* Don't check listen PCBs, check bound-, active- and TIME-WAIT PCBs. */
+    for (i = 1; i < NUM_TCP_PCB_LISTS; i++) {
+      for(cpcb = *tcp_pcb_lists[i]; cpcb != NULL; cpcb = cpcb->next) {
+        if ((cpcb->local_port == pcb->local_port) &&
+            (cpcb->remote_port == port) &&
+            ip_addr_cmp(&cpcb->local_ip, &pcb->local_ip) &&
+            ip_addr_cmp(&cpcb->remote_ip, ipaddr)) {
+          /* linux returns EISCONN here, but ERR_USE should be OK for us */
+          return ERR_USE;
+        }
+      }
+    }
+  }
+#endif /* SO_REUSE */
+  iss = tcp_next_iss();
+  pcb->rcv_nxt = 0;
+  pcb->snd_nxt = iss;
+  pcb->lastack = iss - 1;
+  pcb->snd_lbb = iss - 1;
+  pcb->rcv_wnd = TCP_WND;
+  pcb->rcv_ann_wnd = TCP_WND;
+  pcb->rcv_ann_right_edge = pcb->rcv_nxt;
+  pcb->snd_wnd = TCP_WND;
+  /* As initial send MSS, we use TCP_MSS but limit it to 536.
+     The send MSS is updated when an MSS option is received. */
+  pcb->mss = (TCP_MSS > 536) ? 536 : TCP_MSS;
+#if TCP_CALCULATE_EFF_SEND_MSS
+  pcb->mss = tcp_eff_send_mss(pcb->mss, ipaddr);
+#endif /* TCP_CALCULATE_EFF_SEND_MSS */
+  pcb->cwnd = 1;
+  pcb->ssthresh = pcb->mss * 10;
+#if LWIP_CALLBACK_API
+  pcb->connected = connected;
+#else /* LWIP_CALLBACK_API */  
+  LWIP_UNUSED_ARG(connected);
+#endif /* LWIP_CALLBACK_API */
+
+  LWIP_DEBUGF(TCP_DEBUG, ("tcp_connect: tcp_ticks=%"U32_F" iss=%"U32_F"\n", tcp_ticks, iss));
+
+  /* Send a SYN together with the MSS option. */
+  ret = tcp_enqueue_flags(pcb, TCP_SYN);
+  if (ret == ERR_OK) {
+    /* SYN segment was enqueued, changed the pcbs state now */
+    pcb->state = SYN_SENT;
+    TCP_RMV(&tcp_bound_pcbs, pcb);
+    TCP_REG(&tcp_active_pcbs, pcb);
+    snmp_inc_tcpactiveopens();
+
+    tcp_output(pcb);
+  }
+  return ret;
+}
+
+/**
+ * Called every 500 ms and implements the retransmission timer and the timer that
+ * removes PCBs that have been in TIME-WAIT for enough time. It also increments
+ * various timers such as the inactivity timer in each PCB.
+ *
+ * Automatically called from tcp_tmr().
+ */
+void
+tcp_slowtmr(void)
+{
+  struct tcp_pcb *pcb, *pcb2, *prev;
+  u16_t eff_wnd;
+  u8_t pcb_remove;      /* flag if a PCB should be removed */
+  u8_t pcb_reset;       /* flag if a RST should be sent when removing */
+  err_t err;
+  
+  tcp_debug_print_pcbs(); //DG
+
+  err = ERR_OK;
+
+  ++tcp_ticks;
+  LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: tcp_ticks=%"U32_F"\n", tcp_ticks));
+
+  /* Steps through all of the active PCBs. */
+  prev = NULL;
+  pcb = tcp_active_pcbs;
+  if (pcb == NULL) {
+    LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: no active pcbs\n"));
+  }
+  while (pcb != NULL) {
+    LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: processing active pcb\n"));
+    LWIP_ASSERT("tcp_slowtmr: active pcb->state != CLOSED\n", pcb->state != CLOSED);
+    LWIP_ASSERT("tcp_slowtmr: active pcb->state != LISTEN\n", pcb->state != LISTEN);
+    LWIP_ASSERT("tcp_slowtmr: active pcb->state != TIME-WAIT\n", pcb->state != TIME_WAIT);
+
+    pcb_remove = 0;
+    pcb_reset = 0;
+
+    if (pcb->state == SYN_SENT && pcb->nrtx == TCP_SYNMAXRTX) {
+      ++pcb_remove;
+      LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: max SYN retries reached\n"));
+    }
+    else if (pcb->nrtx == TCP_MAXRTX) {
+      ++pcb_remove;
+      LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: max DATA retries reached\n"));
+    } else {
+      if (pcb->persist_backoff > 0) {
+        /* If snd_wnd is zero, use persist timer to send 1 byte probes
+         * instead of using the standard retransmission mechanism. */
+        pcb->persist_cnt++;
+        if (pcb->persist_cnt >= tcp_persist_backoff[pcb->persist_backoff-1]) {
+          pcb->persist_cnt = 0;
+          if (pcb->persist_backoff < sizeof(tcp_persist_backoff)) {
+            pcb->persist_backoff++;
+          }
+          tcp_zero_window_probe(pcb);
+        }
+      } else {
+        /* Increase the retransmission timer if it is running */
+        if(pcb->rtime >= 0)
+          ++pcb->rtime;
+
+        if (pcb->unacked != NULL && pcb->rtime >= pcb->rto) {
+          /* Time for a retransmission. */
+          LWIP_DEBUGF(TCP_RTO_DEBUG, ("tcp_slowtmr: rtime %"S16_F
+                                      " pcb->rto %"S16_F"\n",
+                                      pcb->rtime, pcb->rto));
+
+          /* Double retransmission time-out unless we are trying to
+           * connect to somebody (i.e., we are in SYN_SENT). */
+          if (pcb->state != SYN_SENT) {
+            pcb->rto = ((pcb->sa >> 3) + pcb->sv) << tcp_backoff[pcb->nrtx];
+          }
+
+          /* Reset the retransmission timer. */
+          pcb->rtime = 0;
+
+          /* Reduce congestion window and ssthresh. */
+          eff_wnd = LWIP_MIN(pcb->cwnd, pcb->snd_wnd);
+          pcb->ssthresh = eff_wnd >> 1;
+          if (pcb->ssthresh < (pcb->mss << 1)) {
+            pcb->ssthresh = (pcb->mss << 1);
+          }
+          pcb->cwnd = pcb->mss;
+          LWIP_DEBUGF(TCP_CWND_DEBUG, ("tcp_slowtmr: cwnd %"U16_F
+                                       " ssthresh %"U16_F"\n",
+                                       pcb->cwnd, pcb->ssthresh));
+ 
+          /* The following needs to be called AFTER cwnd is set to one
+             mss - STJ */
+          tcp_rexmit_rto(pcb);
+        }
+      }
+    }
+    /* Check if this PCB has stayed too long in FIN-WAIT-2 */
+    if (pcb->state == FIN_WAIT_2) {
+      if ((u32_t)(tcp_ticks - pcb->tmr) >
+          TCP_FIN_WAIT_TIMEOUT / TCP_SLOW_INTERVAL) {
+        ++pcb_remove;
+        LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: removing pcb stuck in FIN-WAIT-2\n"));
+      }
+    }
+
+    /* Check if KEEPALIVE should be sent */
+    if((pcb->so_options & SOF_KEEPALIVE) &&
+       ((pcb->state == ESTABLISHED) ||
+        (pcb->state == CLOSE_WAIT))) {
+#if LWIP_TCP_KEEPALIVE
+      if((u32_t)(tcp_ticks - pcb->tmr) >
+         (pcb->keep_idle + (pcb->keep_cnt*pcb->keep_intvl))
+         / TCP_SLOW_INTERVAL)
+#else      
+      if((u32_t)(tcp_ticks - pcb->tmr) >
+         (pcb->keep_idle + TCP_MAXIDLE) / TCP_SLOW_INTERVAL)
+#endif /* LWIP_TCP_KEEPALIVE */
+      {
+        LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: KEEPALIVE timeout. Aborting connection to %"U16_F".%"U16_F".%"U16_F".%"U16_F".\n",
+                                ip4_addr1_16(&pcb->remote_ip), ip4_addr2_16(&pcb->remote_ip),
+                                ip4_addr3_16(&pcb->remote_ip), ip4_addr4_16(&pcb->remote_ip)));
+        
+        ++pcb_remove;
+        ++pcb_reset;
+      }
+#if LWIP_TCP_KEEPALIVE
+      else if((u32_t)(tcp_ticks - pcb->tmr) > 
+              (pcb->keep_idle + pcb->keep_cnt_sent * pcb->keep_intvl)
+              / TCP_SLOW_INTERVAL)
+#else
+      else if((u32_t)(tcp_ticks - pcb->tmr) > 
+              (pcb->keep_idle + pcb->keep_cnt_sent * TCP_KEEPINTVL_DEFAULT) 
+              / TCP_SLOW_INTERVAL)
+#endif /* LWIP_TCP_KEEPALIVE */
+      {
+        tcp_keepalive(pcb);
+        pcb->keep_cnt_sent++;
+      }
+    }
+
+    /* If this PCB has queued out of sequence data, but has been
+       inactive for too long, will drop the data (it will eventually
+       be retransmitted). */
+#if TCP_QUEUE_OOSEQ
+    if (pcb->ooseq != NULL &&
+        (u32_t)tcp_ticks - pcb->tmr >= pcb->rto * TCP_OOSEQ_TIMEOUT) {
+      tcp_segs_free(pcb->ooseq);
+      pcb->ooseq = NULL;
+      LWIP_DEBUGF(TCP_CWND_DEBUG, ("tcp_slowtmr: dropping OOSEQ queued data\n"));
+    }
+#endif /* TCP_QUEUE_OOSEQ */
+
+    /* Check if this PCB has stayed too long in SYN-RCVD */
+    if (pcb->state == SYN_RCVD) {
+      if ((u32_t)(tcp_ticks - pcb->tmr) >
+          TCP_SYN_RCVD_TIMEOUT / TCP_SLOW_INTERVAL) {
+        ++pcb_remove;
+        LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: removing pcb stuck in SYN-RCVD\n"));
+      }
+    }
+
+    /* Check if this PCB has stayed too long in LAST-ACK */
+    if (pcb->state == LAST_ACK) {
+      if ((u32_t)(tcp_ticks - pcb->tmr) > 2 * TCP_MSL / TCP_SLOW_INTERVAL) {
+        ++pcb_remove;
+        LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: removing pcb stuck in LAST-ACK\n"));
+      }
+    }
+
+    /* If the PCB should be removed, do it. */
+    if (pcb_remove) {
+      tcp_pcb_purge(pcb);
+      /* Remove PCB from tcp_active_pcbs list. */
+      if (prev != NULL) {
+        LWIP_ASSERT("tcp_slowtmr: middle tcp != tcp_active_pcbs", pcb != tcp_active_pcbs);
+        prev->next = pcb->next;
+      } else {
+        /* This PCB was the first. */
+        LWIP_ASSERT("tcp_slowtmr: first pcb == tcp_active_pcbs", tcp_active_pcbs == pcb);
+        tcp_active_pcbs = pcb->next;
+      }
+
+      TCP_EVENT_ERR(pcb->errf, pcb->callback_arg, ERR_ABRT);
+      if (pcb_reset) {
+        tcp_rst(pcb->snd_nxt, pcb->rcv_nxt, &pcb->local_ip, &pcb->remote_ip,
+          pcb->local_port, pcb->remote_port);
+      }
+
+      pcb2 = pcb->next;
+      memp_free(MEMP_TCP_PCB, pcb);
+      pcb = pcb2;
+    } else {
+      /* get the 'next' element now and work with 'prev' below (in case of abort) */
+      prev = pcb;
+      pcb = pcb->next;
+
+      /* We check if we should poll the connection. */
+      ++prev->polltmr;
+      if (prev->polltmr >= prev->pollinterval) {
+        prev->polltmr = 0;
+        LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: polling application\n"));
+        TCP_EVENT_POLL(prev, err);
+        /* if err == ERR_ABRT, 'prev' is already deallocated */
+        if (err == ERR_OK) {
+          tcp_output(prev);
+        }
+      }
+    }
+  }
+
+  
+  /* Steps through all of the TIME-WAIT PCBs. */
+  prev = NULL;    
+  pcb = tcp_tw_pcbs;
+  while (pcb != NULL) {
+    LWIP_ASSERT("tcp_slowtmr: TIME-WAIT pcb->state == TIME-WAIT", pcb->state == TIME_WAIT);
+    pcb_remove = 0;
+
+    /* Check if this PCB has stayed long enough in TIME-WAIT */
+    if ((u32_t)(tcp_ticks - pcb->tmr) > 2 * TCP_MSL / TCP_SLOW_INTERVAL) {
+      ++pcb_remove;
+    }
+    
+
+
+    /* If the PCB should be removed, do it. */
+    if (pcb_remove) {
+      tcp_pcb_purge(pcb);
+      /* Remove PCB from tcp_tw_pcbs list. */
+      if (prev != NULL) {
+        LWIP_ASSERT("tcp_slowtmr: middle tcp != tcp_tw_pcbs", pcb != tcp_tw_pcbs);
+        prev->next = pcb->next;
+      } else {
+        /* This PCB was the first. */
+        LWIP_ASSERT("tcp_slowtmr: first pcb == tcp_tw_pcbs", tcp_tw_pcbs == pcb);
+        tcp_tw_pcbs = pcb->next;
+      }
+      pcb2 = pcb->next;
+      memp_free(MEMP_TCP_PCB, pcb);
+      pcb = pcb2;
+    } else {
+      prev = pcb;
+      pcb = pcb->next;
+    }
+  }
+}
+
+/**
+ * Is called every TCP_FAST_INTERVAL (250 ms) and process data previously
+ * "refused" by upper layer (application) and sends delayed ACKs.
+ *
+ * Automatically called from tcp_tmr().
+ */
+void
+tcp_fasttmr(void)
+{
+  struct tcp_pcb *pcb = tcp_active_pcbs;
+
+  while(pcb != NULL) {
+    struct tcp_pcb *next = pcb->next;
+    /* If there is data which was previously "refused" by upper layer */
+    if (pcb->refused_data != NULL) {
+      /* Notify again application with data previously received. */
+      err_t err;
+      LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_fasttmr: notify kept packet\n"));
+      TCP_EVENT_RECV(pcb, pcb->refused_data, ERR_OK, err);
+      if (err == ERR_OK) {
+        pcb->refused_data = NULL;
+      } else if (err == ERR_ABRT) {
+        /* if err == ERR_ABRT, 'pcb' is already deallocated */
+        pcb = NULL;
+      }
+    }
+
+    /* send delayed ACKs */  
+    if (pcb && (pcb->flags & TF_ACK_DELAY)) {
+      LWIP_DEBUGF(TCP_DEBUG, ("tcp_fasttmr: delayed ACK\n"));
+      tcp_ack_now(pcb);
+      tcp_output(pcb);
+      pcb->flags &= ~(TF_ACK_DELAY | TF_ACK_NOW);
+    }
+
+    pcb = next;
+  }
+}
+
+/**
+ * Deallocates a list of TCP segments (tcp_seg structures).
+ *
+ * @param seg tcp_seg list of TCP segments to free
+ */
+void
+tcp_segs_free(struct tcp_seg *seg)
+{
+  while (seg != NULL) {
+    struct tcp_seg *next = seg->next;
+    tcp_seg_free(seg);
+    seg = next;
+  }
+}
+
+/**
+ * Frees a TCP segment (tcp_seg structure).
+ *
+ * @param seg single tcp_seg to free
+ */
+void
+tcp_seg_free(struct tcp_seg *seg)
+{
+  if (seg != NULL) {
+    if (seg->p != NULL) {
+      pbuf_free(seg->p);
+#if TCP_DEBUG
+      seg->p = NULL;
+#endif /* TCP_DEBUG */
+    }
+    memp_free(MEMP_TCP_SEG, seg);
+  }
+}
+
+/**
+ * Sets the priority of a connection.
+ *
+ * @param pcb the tcp_pcb to manipulate
+ * @param prio new priority
+ */
+void
+tcp_setprio(struct tcp_pcb *pcb, u8_t prio)
+{
+  pcb->prio = prio;
+}
+
+#if TCP_QUEUE_OOSEQ
+/**
+ * Returns a copy of the given TCP segment.
+ * The pbuf and data are not copied, only the pointers
+ *
+ * @param seg the old tcp_seg
+ * @return a copy of seg
+ */ 
+struct tcp_seg *
+tcp_seg_copy(struct tcp_seg *seg)
+{
+  struct tcp_seg *cseg;
+
+  cseg = (struct tcp_seg *)memp_malloc(MEMP_TCP_SEG);
+  if (cseg == NULL) {
+    return NULL;
+  }
+  SMEMCPY((u8_t *)cseg, (const u8_t *)seg, sizeof(struct tcp_seg)); 
+  pbuf_ref(cseg->p);
+  return cseg;
+}
+#endif /* TCP_QUEUE_OOSEQ */
+
+#if LWIP_CALLBACK_API
+/**
+ * Default receive callback that is called if the user didn't register
+ * a recv callback for the pcb.
+ */
+err_t
+tcp_recv_null(void *arg, struct tcp_pcb *pcb, struct pbuf *p, err_t err)
+{
+  LWIP_UNUSED_ARG(arg);
+  if (p != NULL) {
+    tcp_recved(pcb, p->tot_len);
+    pbuf_free(p);
+  } else if (err == ERR_OK) {
+    return tcp_close(pcb);
+  }
+  return ERR_OK;
+}
+#endif /* LWIP_CALLBACK_API */
+
+/**
+ * Kills the oldest active connection that has lower priority than prio.
+ *
+ * @param prio minimum priority
+ */
+static void
+tcp_kill_prio(u8_t prio)
+{
+  struct tcp_pcb *pcb, *inactive;
+  u32_t inactivity;
+  u8_t mprio;
+
+
+  mprio = TCP_PRIO_MAX;
+  
+  /* We kill the oldest active connection that has lower priority than prio. */
+  inactivity = 0;
+  inactive = NULL;
+  for(pcb = tcp_active_pcbs; pcb != NULL; pcb = pcb->next) {
+    if (pcb->prio <= prio &&
+       pcb->prio <= mprio &&
+       (u32_t)(tcp_ticks - pcb->tmr) >= inactivity) {
+      inactivity = tcp_ticks - pcb->tmr;
+      inactive = pcb;
+      mprio = pcb->prio;
+    }
+  }
+  if (inactive != NULL) {
+    LWIP_DEBUGF(TCP_DEBUG, ("tcp_kill_prio: killing oldest PCB %p (%"S32_F")\n",
+           (void *)inactive, inactivity));
+    tcp_abort(inactive);
+  }
+}
+
+/**
+ * Kills the oldest connection that is in TIME_WAIT state.
+ * Called from tcp_alloc() if no more connections are available.
+ */
+static void
+tcp_kill_timewait(void)
+{
+  struct tcp_pcb *pcb, *inactive;
+  u32_t inactivity;
+
+  inactivity = 0;
+  inactive = NULL;
+  /* Go through the list of TIME_WAIT pcbs and get the oldest pcb. */
+  for(pcb = tcp_tw_pcbs; pcb != NULL; pcb = pcb->next) {
+    if ((u32_t)(tcp_ticks - pcb->tmr) >= inactivity) {
+      inactivity = tcp_ticks - pcb->tmr;
+      inactive = pcb;
+    }
+  }
+  if (inactive != NULL) {
+    LWIP_DEBUGF(TCP_DEBUG, ("tcp_kill_timewait: killing oldest TIME-WAIT PCB %p (%"S32_F")\n",
+           (void *)inactive, inactivity));
+    tcp_abort(inactive);
+  }
+}
+
+/**
+ * Allocate a new tcp_pcb structure.
+ *
+ * @param prio priority for the new pcb
+ * @return a new tcp_pcb that initially is in state CLOSED
+ */
+struct tcp_pcb *
+tcp_alloc(u8_t prio)
+{
+  struct tcp_pcb *pcb;
+  u32_t iss;
+  
+  pcb = (struct tcp_pcb *)memp_malloc(MEMP_TCP_PCB);
+  if (pcb == NULL) {
+    /* Try killing oldest connection in TIME-WAIT. */
+    LWIP_DEBUGF(TCP_DEBUG, ("tcp_alloc: killing off oldest TIME-WAIT connection\n"));
+    tcp_kill_timewait();
+    /* Try to allocate a tcp_pcb again. */
+    pcb = (struct tcp_pcb *)memp_malloc(MEMP_TCP_PCB);
+    if (pcb == NULL) {
+      /* Try killing active connections with lower priority than the new one. */
+      LWIP_DEBUGF(TCP_DEBUG, ("tcp_alloc: killing connection with prio lower than %d\n", prio));
+      tcp_kill_prio(prio);
+      /* Try to allocate a tcp_pcb again. */
+      pcb = (struct tcp_pcb *)memp_malloc(MEMP_TCP_PCB);
+      if (pcb != NULL) {
+        /* adjust err stats: memp_malloc failed twice before */
+        MEMP_STATS_DEC(err, MEMP_TCP_PCB);
+      }
+    }
+    if (pcb != NULL) {
+      /* adjust err stats: timewait PCB was freed above */
+      MEMP_STATS_DEC(err, MEMP_TCP_PCB);
+    }
+  }
+  if (pcb != NULL) {
+    memset(pcb, 0, sizeof(struct tcp_pcb));
+    pcb->prio = prio;
+    pcb->snd_buf = TCP_SND_BUF;
+    pcb->snd_queuelen = 0;
+    pcb->rcv_wnd = TCP_WND;
+    pcb->rcv_ann_wnd = TCP_WND;
+    pcb->tos = 0;
+    pcb->ttl = TCP_TTL;
+    /* As initial send MSS, we use TCP_MSS but limit it to 536.
+       The send MSS is updated when an MSS option is received. */
+    pcb->mss = (TCP_MSS > 536) ? 536 : TCP_MSS;
+    pcb->rto = 3000 / TCP_SLOW_INTERVAL;
+    pcb->sa = 0;
+    pcb->sv = 3000 / TCP_SLOW_INTERVAL;
+    pcb->rtime = -1;
+    pcb->cwnd = 1;
+    iss = tcp_next_iss();
+    pcb->snd_wl2 = iss;
+    pcb->snd_nxt = iss;
+    pcb->lastack = iss;
+    pcb->snd_lbb = iss;   
+    pcb->tmr = tcp_ticks;
+    
+    LWIP_DEBUGF(TCP_DEBUG, ("tcp_alloc: tcp_ticks=%"U32_F" iss=%"U32_F"\n", tcp_ticks, iss));
+
+    pcb->polltmr = 0;
+
+#if LWIP_CALLBACK_API
+    pcb->recv = tcp_recv_null;
+#endif /* LWIP_CALLBACK_API */  
+    
+    /* Init KEEPALIVE timer */
+    pcb->keep_idle  = TCP_KEEPIDLE_DEFAULT;
+    
+#if LWIP_TCP_KEEPALIVE
+    pcb->keep_intvl = TCP_KEEPINTVL_DEFAULT;
+    pcb->keep_cnt   = TCP_KEEPCNT_DEFAULT;
+#endif /* LWIP_TCP_KEEPALIVE */
+
+    pcb->keep_cnt_sent = 0;
+  }
+  return pcb;
+}
+
+/**
+ * Creates a new TCP protocol control block but doesn't place it on
+ * any of the TCP PCB lists.
+ * The pcb is not put on any list until binding using tcp_bind().
+ *
+ * @internal: Maybe there should be a idle TCP PCB list where these
+ * PCBs are put on. Port reservation using tcp_bind() is implemented but
+ * allocated pcbs that are not bound can't be killed automatically if wanting
+ * to allocate a pcb with higher prio (@see tcp_kill_prio())
+ *
+ * @return a new tcp_pcb that initially is in state CLOSED
+ */
+struct tcp_pcb *
+tcp_new(void)
+{
+  return tcp_alloc(TCP_PRIO_NORMAL);
+}
+
+/**
+ * Used to specify the argument that should be passed callback
+ * functions.
+ *
+ * @param pcb tcp_pcb to set the callback argument
+ * @param arg void pointer argument to pass to callback functions
+ */ 
+void
+tcp_arg(struct tcp_pcb *pcb, void *arg)
+{  
+  pcb->callback_arg = arg;
+}
+#if LWIP_CALLBACK_API
+
+/**
+ * Used to specify the function that should be called when a TCP
+ * connection receives data.
+ *
+ * @param pcb tcp_pcb to set the recv callback
+ * @param recv callback function to call for this pcb when data is received
+ */ 
+void
+tcp_recv(struct tcp_pcb *pcb, tcp_recv_fn recv)
+{
+  pcb->recv = recv;
+}
+
+/**
+ * Used to specify the function that should be called when TCP data
+ * has been successfully delivered to the remote host.
+ *
+ * @param pcb tcp_pcb to set the sent callback
+ * @param sent callback function to call for this pcb when data is successfully sent
+ */ 
+void
+tcp_sent(struct tcp_pcb *pcb, tcp_sent_fn sent)
+{
+  pcb->sent = sent;
+}
+
+/**
+ * Used to specify the function that should be called when a fatal error
+ * has occured on the connection.
+ *
+ * @param pcb tcp_pcb to set the err callback
+ * @param err callback function to call for this pcb when a fatal error
+ *        has occured on the connection
+ */ 
+void
+tcp_err(struct tcp_pcb *pcb, tcp_err_fn err)
+{
+  pcb->errf = err;
+}
+
+/**
+ * Used for specifying the function that should be called when a
+ * LISTENing connection has been connected to another host.
+ *
+ * @param pcb tcp_pcb to set the accept callback
+ * @param accept callback function to call for this pcb when LISTENing
+ *        connection has been connected to another host
+ */ 
+void
+tcp_accept(struct tcp_pcb *pcb, tcp_accept_fn accept)
+{
+  pcb->accept = accept;
+}
+#endif /* LWIP_CALLBACK_API */
+
+
+/**
+ * Used to specify the function that should be called periodically
+ * from TCP. The interval is specified in terms of the TCP coarse
+ * timer interval, which is called twice a second.
+ *
+ */ 
+void
+tcp_poll(struct tcp_pcb *pcb, tcp_poll_fn poll, u8_t interval)
+{
+#if LWIP_CALLBACK_API
+  pcb->poll = poll;
+#else /* LWIP_CALLBACK_API */  
+  LWIP_UNUSED_ARG(poll);
+#endif /* LWIP_CALLBACK_API */  
+  pcb->pollinterval = interval;
+}
+
+/**
+ * Purges a TCP PCB. Removes any buffered data and frees the buffer memory
+ * (pcb->ooseq, pcb->unsent and pcb->unacked are freed).
+ *
+ * @param pcb tcp_pcb to purge. The pcb itself is not deallocated!
+ */
+void
+tcp_pcb_purge(struct tcp_pcb *pcb)
+{
+  if (pcb->state != CLOSED &&
+     pcb->state != TIME_WAIT &&
+     pcb->state != LISTEN) {
+
+    LWIP_DEBUGF(TCP_DEBUG, ("tcp_pcb_purge\n"));
+
+#if TCP_LISTEN_BACKLOG
+    if (pcb->state == SYN_RCVD) {
+      /* Need to find the corresponding listen_pcb and decrease its accepts_pending */
+      struct tcp_pcb_listen *lpcb;
+      LWIP_ASSERT("tcp_pcb_purge: pcb->state == SYN_RCVD but tcp_listen_pcbs is NULL",
+        tcp_listen_pcbs.listen_pcbs != NULL);
+      for (lpcb = tcp_listen_pcbs.listen_pcbs; lpcb != NULL; lpcb = lpcb->next) {
+        if ((lpcb->local_port == pcb->local_port) &&
+            (ip_addr_isany(&lpcb->local_ip) ||
+             ip_addr_cmp(&pcb->local_ip, &lpcb->local_ip))) {
+            /* port and address of the listen pcb match the timed-out pcb */
+            LWIP_ASSERT("tcp_pcb_purge: listen pcb does not have accepts pending",
+              lpcb->accepts_pending > 0);
+            lpcb->accepts_pending--;
+            break;
+          }
+      }
+    }
+#endif /* TCP_LISTEN_BACKLOG */
+
+
+    if (pcb->refused_data != NULL) {
+      LWIP_DEBUGF(TCP_DEBUG, ("tcp_pcb_purge: data left on ->refused_data\n"));
+      pbuf_free(pcb->refused_data);
+      pcb->refused_data = NULL;
+    }
+    if (pcb->unsent != NULL) {
+      LWIP_DEBUGF(TCP_DEBUG, ("tcp_pcb_purge: not all data sent\n"));
+    }
+    if (pcb->unacked != NULL) {
+      LWIP_DEBUGF(TCP_DEBUG, ("tcp_pcb_purge: data left on ->unacked\n"));
+    }
+#if TCP_QUEUE_OOSEQ
+    if (pcb->ooseq != NULL) {
+      LWIP_DEBUGF(TCP_DEBUG, ("tcp_pcb_purge: data left on ->ooseq\n"));
+    }
+    tcp_segs_free(pcb->ooseq);
+    pcb->ooseq = NULL;
+#endif /* TCP_QUEUE_OOSEQ */
+
+    /* Stop the retransmission timer as it will expect data on unacked
+       queue if it fires */
+    pcb->rtime = -1;
+
+    tcp_segs_free(pcb->unsent);
+    tcp_segs_free(pcb->unacked);
+    pcb->unacked = pcb->unsent = NULL;
+#if TCP_OVERSIZE
+    pcb->unsent_oversize = 0;
+#endif /* TCP_OVERSIZE */
+  }
+}
+
+/**
+ * Purges the PCB and removes it from a PCB list. Any delayed ACKs are sent first.
+ *
+ * @param pcblist PCB list to purge.
+ * @param pcb tcp_pcb to purge. The pcb itself is NOT deallocated!
+ */
+void
+tcp_pcb_remove(struct tcp_pcb **pcblist, struct tcp_pcb *pcb)
+{
+  TCP_RMV(pcblist, pcb);
+
+  tcp_pcb_purge(pcb);
+  
+  /* if there is an outstanding delayed ACKs, send it */
+  if (pcb->state != TIME_WAIT &&
+     pcb->state != LISTEN &&
+     pcb->flags & TF_ACK_DELAY) {
+    pcb->flags |= TF_ACK_NOW;
+    tcp_output(pcb);
+  }
+
+  if (pcb->state != LISTEN) {
+    LWIP_ASSERT("unsent segments leaking", pcb->unsent == NULL);
+    LWIP_ASSERT("unacked segments leaking", pcb->unacked == NULL);
+#if TCP_QUEUE_OOSEQ
+    LWIP_ASSERT("ooseq segments leaking", pcb->ooseq == NULL);
+#endif /* TCP_QUEUE_OOSEQ */
+  }
+
+  pcb->state = CLOSED;
+
+  LWIP_ASSERT("tcp_pcb_remove: tcp_pcbs_sane()", tcp_pcbs_sane());
+}
+
+/**
+ * Calculates a new initial sequence number for new connections.
+ *
+ * @return u32_t pseudo random sequence number
+ */
+u32_t
+tcp_next_iss(void)
+{
+  static u32_t iss = 6510;
+  
+  iss += tcp_ticks;       /* XXX */
+  return iss;
+}
+
+#if TCP_CALCULATE_EFF_SEND_MSS
+/**
+ * Calcluates the effective send mss that can be used for a specific IP address
+ * by using ip_route to determin the netif used to send to the address and
+ * calculating the minimum of TCP_MSS and that netif's mtu (if set).
+ */
+u16_t
+tcp_eff_send_mss(u16_t sendmss, ip_addr_t *addr)
+{
+  u16_t mss_s;
+  struct netif *outif;
+
+  outif = ip_route(addr);
+  if ((outif != NULL) && (outif->mtu != 0)) {
+    mss_s = outif->mtu - IP_HLEN - TCP_HLEN;
+    /* RFC 1122, chap 4.2.2.6:
+     * Eff.snd.MSS = min(SendMSS+20, MMS_S) - TCPhdrsize - IPoptionsize
+     * We correct for TCP options in tcp_write(), and don't support IP options.
+     */
+    sendmss = LWIP_MIN(sendmss, mss_s);
+  }
+  return sendmss;
+}
+#endif /* TCP_CALCULATE_EFF_SEND_MSS */
+
+const char*
+tcp_debug_state_str(enum tcp_state s)
+{
+  return tcp_state_str[s];
+}
+
+#if TCP_DEBUG || TCP_INPUT_DEBUG || TCP_OUTPUT_DEBUG
+/**
+ * Print a tcp header for debugging purposes.
+ *
+ * @param tcphdr pointer to a struct tcp_hdr
+ */
+void
+tcp_debug_print(struct tcp_hdr *tcphdr)
+{
+  LWIP_DEBUGF(TCP_DEBUG, ("TCP header:\n"));
+  LWIP_DEBUGF(TCP_DEBUG, ("+-------------------------------+\n"));
+  LWIP_DEBUGF(TCP_DEBUG, ("|    %5"U16_F"      |    %5"U16_F"      | (src port, dest port)\n",
+         ntohs(tcphdr->src), ntohs(tcphdr->dest)));
+  LWIP_DEBUGF(TCP_DEBUG, ("+-------------------------------+\n"));
+  LWIP_DEBUGF(TCP_DEBUG, ("|           %010"U32_F"          | (seq no)\n",
+          ntohl(tcphdr->seqno)));
+  LWIP_DEBUGF(TCP_DEBUG, ("+-------------------------------+\n"));
+  LWIP_DEBUGF(TCP_DEBUG, ("|           %010"U32_F"          | (ack no)\n",
+         ntohl(tcphdr->ackno)));
+  LWIP_DEBUGF(TCP_DEBUG, ("+-------------------------------+\n"));
+  LWIP_DEBUGF(TCP_DEBUG, ("| %2"U16_F" |   |%"U16_F"%"U16_F"%"U16_F"%"U16_F"%"U16_F"%"U16_F"|     %5"U16_F"     | (hdrlen, flags (",
+       TCPH_HDRLEN(tcphdr),
+         TCPH_FLAGS(tcphdr) >> 5 & 1,
+         TCPH_FLAGS(tcphdr) >> 4 & 1,
+         TCPH_FLAGS(tcphdr) >> 3 & 1,
+         TCPH_FLAGS(tcphdr) >> 2 & 1,
+         TCPH_FLAGS(tcphdr) >> 1 & 1,
+         TCPH_FLAGS(tcphdr) & 1,
+         ntohs(tcphdr->wnd)));
+  tcp_debug_print_flags(TCPH_FLAGS(tcphdr));
+  LWIP_DEBUGF(TCP_DEBUG, ("), win)\n"));
+  LWIP_DEBUGF(TCP_DEBUG, ("+-------------------------------+\n"));
+  LWIP_DEBUGF(TCP_DEBUG, ("|    0x%04"X16_F"     |     %5"U16_F"     | (chksum, urgp)\n",
+         ntohs(tcphdr->chksum), ntohs(tcphdr->urgp)));
+  LWIP_DEBUGF(TCP_DEBUG, ("+-------------------------------+\n"));
+}
+
+/**
+ * Print a tcp state for debugging purposes.
+ *
+ * @param s enum tcp_state to print
+ */
+void
+tcp_debug_print_state(enum tcp_state s)
+{
+  LWIP_DEBUGF(TCP_DEBUG, ("State: %s\n", tcp_state_str[s]));
+}
+
+/**
+ * Print tcp flags for debugging purposes.
+ *
+ * @param flags tcp flags, all active flags are printed
+ */
+void
+tcp_debug_print_flags(u8_t flags)
+{
+  if (flags & TCP_FIN) {
+    LWIP_DEBUGF(TCP_DEBUG, ("FIN "));
+  }
+  if (flags & TCP_SYN) {
+    LWIP_DEBUGF(TCP_DEBUG, ("SYN "));
+  }
+  if (flags & TCP_RST) {
+    LWIP_DEBUGF(TCP_DEBUG, ("RST "));
+  }
+  if (flags & TCP_PSH) {
+    LWIP_DEBUGF(TCP_DEBUG, ("PSH "));
+  }
+  if (flags & TCP_ACK) {
+    LWIP_DEBUGF(TCP_DEBUG, ("ACK "));
+  }
+  if (flags & TCP_URG) {
+    LWIP_DEBUGF(TCP_DEBUG, ("URG "));
+  }
+  if (flags & TCP_ECE) {
+    LWIP_DEBUGF(TCP_DEBUG, ("ECE "));
+  }
+  if (flags & TCP_CWR) {
+    LWIP_DEBUGF(TCP_DEBUG, ("CWR "));
+  }
+  LWIP_DEBUGF(TCP_DEBUG, ("\n"));
+}
+
+/**
+ * Print all tcp_pcbs in every list for debugging purposes.
+ */
+void
+tcp_debug_print_pcbs(void)
+{
+  struct tcp_pcb *pcb;
+  LWIP_DEBUGF(TCP_DEBUG, ("Active PCB states:\n"));
+  for(pcb = tcp_active_pcbs; pcb != NULL; pcb = pcb->next) {
+    LWIP_DEBUGF(TCP_DEBUG, ("Local port %"U16_F", foreign port %"U16_F" snd_nxt %"U32_F" rcv_nxt %"U32_F" ",
+                       pcb->local_port, pcb->remote_port,
+                       pcb->snd_nxt, pcb->rcv_nxt));
+    tcp_debug_print_state(pcb->state);
+  }    
+  LWIP_DEBUGF(TCP_DEBUG, ("Listen PCB states:\n"));
+  for(pcb = (struct tcp_pcb *)tcp_listen_pcbs.pcbs; pcb != NULL; pcb = pcb->next) {
+    LWIP_DEBUGF(TCP_DEBUG, ("Local port %"U16_F", foreign port %"U16_F" snd_nxt %"U32_F" rcv_nxt %"U32_F" ",
+                       pcb->local_port, pcb->remote_port,
+                       pcb->snd_nxt, pcb->rcv_nxt));
+    tcp_debug_print_state(pcb->state);
+  }    
+  LWIP_DEBUGF(TCP_DEBUG, ("TIME-WAIT PCB states:\n"));
+  for(pcb = tcp_tw_pcbs; pcb != NULL; pcb = pcb->next) {
+    LWIP_DEBUGF(TCP_DEBUG, ("Local port %"U16_F", foreign port %"U16_F" snd_nxt %"U32_F" rcv_nxt %"U32_F" ",
+                       pcb->local_port, pcb->remote_port,
+                       pcb->snd_nxt, pcb->rcv_nxt));
+    tcp_debug_print_state(pcb->state);
+  }    
+}
+
+/**
+ * Check state consistency of the tcp_pcb lists.
+ */
+s16_t
+tcp_pcbs_sane(void)
+{
+  struct tcp_pcb *pcb;
+  for(pcb = tcp_active_pcbs; pcb != NULL; pcb = pcb->next) {
+    LWIP_ASSERT("tcp_pcbs_sane: active pcb->state != CLOSED", pcb->state != CLOSED);
+    LWIP_ASSERT("tcp_pcbs_sane: active pcb->state != LISTEN", pcb->state != LISTEN);
+    LWIP_ASSERT("tcp_pcbs_sane: active pcb->state != TIME-WAIT", pcb->state != TIME_WAIT);
+  }
+  for(pcb = tcp_tw_pcbs; pcb != NULL; pcb = pcb->next) {
+    LWIP_ASSERT("tcp_pcbs_sane: tw pcb->state == TIME-WAIT", pcb->state == TIME_WAIT);
+  }
+  return 1;
+}
+#endif /* TCP_DEBUG */
+
+#endif /* LWIP_TCP */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/core/tcp_in.c	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,1569 @@
+/**
+ * @file
+ * Transmission Control Protocol, incoming traffic
+ *
+ * The input processing functions of the TCP layer.
+ *
+ * These functions are generally called in the order (ip_input() ->)
+ * tcp_input() -> * tcp_process() -> tcp_receive() (-> application).
+ * 
+ */
+
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ *
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+
+#include "lwip/opt.h"
+
+#if LWIP_TCP /* don't build if not configured for use in lwipopts.h */
+
+#include "lwip/tcp_impl.h"
+#include "lwip/def.h"
+#include "lwip/ip_addr.h"
+#include "lwip/netif.h"
+#include "lwip/mem.h"
+#include "lwip/memp.h"
+#include "lwip/inet_chksum.h"
+#include "lwip/stats.h"
+#include "lwip/snmp.h"
+#include "arch/perf.h"
+
+/* These variables are global to all functions involved in the input
+   processing of TCP segments. They are set by the tcp_input()
+   function. */
+static struct tcp_seg inseg;
+static struct tcp_hdr *tcphdr;
+static struct ip_hdr *iphdr;
+static u32_t seqno, ackno;
+static u8_t flags;
+static u16_t tcplen;
+
+static u8_t recv_flags;
+static struct pbuf *recv_data;
+
+struct tcp_pcb *tcp_input_pcb;
+
+/* Forward declarations. */
+static err_t tcp_process(struct tcp_pcb *pcb);
+static void tcp_receive(struct tcp_pcb *pcb);
+static void tcp_parseopt(struct tcp_pcb *pcb);
+
+static err_t tcp_listen_input(struct tcp_pcb_listen *pcb);
+static err_t tcp_timewait_input(struct tcp_pcb *pcb);
+
+/**
+ * The initial input processing of TCP. It verifies the TCP header, demultiplexes
+ * the segment between the PCBs and passes it on to tcp_process(), which implements
+ * the TCP finite state machine. This function is called by the IP layer (in
+ * ip_input()).
+ *
+ * @param p received TCP segment to process (p->payload pointing to the IP header)
+ * @param inp network interface on which this segment was received
+ */
+void
+tcp_input(struct pbuf *p, struct netif *inp)
+{
+  struct tcp_pcb *pcb, *prev;
+  struct tcp_pcb_listen *lpcb;
+#if SO_REUSE
+  struct tcp_pcb *lpcb_prev = NULL;
+  struct tcp_pcb_listen *lpcb_any = NULL;
+#endif /* SO_REUSE */
+  u8_t hdrlen;
+  err_t err;
+
+  PERF_START;
+
+  TCP_STATS_INC(tcp.recv);
+  snmp_inc_tcpinsegs();
+
+  iphdr = (struct ip_hdr *)p->payload;
+  tcphdr = (struct tcp_hdr *)((u8_t *)p->payload + IPH_HL(iphdr) * 4);
+
+#if TCP_INPUT_DEBUG
+  tcp_debug_print(tcphdr);
+#endif
+
+  /* remove header from payload */
+  if (pbuf_header(p, -((s16_t)(IPH_HL(iphdr) * 4))) || (p->tot_len < sizeof(struct tcp_hdr))) {
+    /* drop short packets */
+    LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_input: short packet (%"U16_F" bytes) discarded\n", p->tot_len));
+    TCP_STATS_INC(tcp.lenerr);
+    TCP_STATS_INC(tcp.drop);
+    snmp_inc_tcpinerrs();
+    pbuf_free(p);
+    return;
+  }
+
+  /* Don't even process incoming broadcasts/multicasts. */
+  if (ip_addr_isbroadcast(&current_iphdr_dest, inp) ||
+      ip_addr_ismulticast(&current_iphdr_dest)) {
+    TCP_STATS_INC(tcp.proterr);
+    TCP_STATS_INC(tcp.drop);
+    snmp_inc_tcpinerrs();
+    pbuf_free(p);
+    return;
+  }
+
+#if CHECKSUM_CHECK_TCP
+  /* Verify TCP checksum. */
+  if (inet_chksum_pseudo(p, ip_current_src_addr(), ip_current_dest_addr(),
+      IP_PROTO_TCP, p->tot_len) != 0) {
+      LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_input: packet discarded due to failing checksum 0x%04"X16_F"\n",
+        inet_chksum_pseudo(p, ip_current_src_addr(), ip_current_dest_addr(),
+      IP_PROTO_TCP, p->tot_len)));
+#if TCP_DEBUG
+    tcp_debug_print(tcphdr);
+#endif /* TCP_DEBUG */
+    TCP_STATS_INC(tcp.chkerr);
+    TCP_STATS_INC(tcp.drop);
+    snmp_inc_tcpinerrs();
+    pbuf_free(p);
+    return;
+  }
+#endif
+
+  /* Move the payload pointer in the pbuf so that it points to the
+     TCP data instead of the TCP header. */
+  hdrlen = TCPH_HDRLEN(tcphdr);
+  if(pbuf_header(p, -(hdrlen * 4))){
+    /* drop short packets */
+    LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_input: short packet\n"));
+    TCP_STATS_INC(tcp.lenerr);
+    TCP_STATS_INC(tcp.drop);
+    snmp_inc_tcpinerrs();
+    pbuf_free(p);
+    return;
+  }
+
+  /* Convert fields in TCP header to host byte order. */
+  tcphdr->src = ntohs(tcphdr->src);
+  tcphdr->dest = ntohs(tcphdr->dest);
+  seqno = tcphdr->seqno = ntohl(tcphdr->seqno);
+  ackno = tcphdr->ackno = ntohl(tcphdr->ackno);
+  tcphdr->wnd = ntohs(tcphdr->wnd);
+
+  flags = TCPH_FLAGS(tcphdr);
+  tcplen = p->tot_len + ((flags & (TCP_FIN | TCP_SYN)) ? 1 : 0);
+
+  /* Demultiplex an incoming segment. First, we check if it is destined
+     for an active connection. */
+  prev = NULL;
+
+  
+  for(pcb = tcp_active_pcbs; pcb != NULL; pcb = pcb->next) {
+    LWIP_ASSERT("tcp_input: active pcb->state != CLOSED", pcb->state != CLOSED);
+    LWIP_ASSERT("tcp_input: active pcb->state != TIME-WAIT", pcb->state != TIME_WAIT);
+    LWIP_ASSERT("tcp_input: active pcb->state != LISTEN", pcb->state != LISTEN);
+    if (pcb->remote_port == tcphdr->src &&
+       pcb->local_port == tcphdr->dest &&
+       ip_addr_cmp(&(pcb->remote_ip), &current_iphdr_src) &&
+       ip_addr_cmp(&(pcb->local_ip), &current_iphdr_dest)) {
+
+      /* Move this PCB to the front of the list so that subsequent
+         lookups will be faster (we exploit locality in TCP segment
+         arrivals). */
+      LWIP_ASSERT("tcp_input: pcb->next != pcb (before cache)", pcb->next != pcb);
+      if (prev != NULL) {
+        prev->next = pcb->next;
+        pcb->next = tcp_active_pcbs;
+        tcp_active_pcbs = pcb;
+      }
+      LWIP_ASSERT("tcp_input: pcb->next != pcb (after cache)", pcb->next != pcb);
+      break;
+    }
+    prev = pcb;
+  }
+
+  if (pcb == NULL) {
+    /* If it did not go to an active connection, we check the connections
+       in the TIME-WAIT state. */
+    for(pcb = tcp_tw_pcbs; pcb != NULL; pcb = pcb->next) {
+      LWIP_ASSERT("tcp_input: TIME-WAIT pcb->state == TIME-WAIT", pcb->state == TIME_WAIT);
+      if (pcb->remote_port == tcphdr->src &&
+         pcb->local_port == tcphdr->dest &&
+         ip_addr_cmp(&(pcb->remote_ip), &current_iphdr_src) &&
+         ip_addr_cmp(&(pcb->local_ip), &current_iphdr_dest)) {
+        /* We don't really care enough to move this PCB to the front
+           of the list since we are not very likely to receive that
+           many segments for connections in TIME-WAIT. */
+        LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_input: packed for TIME_WAITing connection.\n"));
+        tcp_timewait_input(pcb);
+        pbuf_free(p);
+        return;
+      }
+    }
+
+    /* Finally, if we still did not get a match, we check all PCBs that
+       are LISTENing for incoming connections. */
+    prev = NULL;
+    for(lpcb = tcp_listen_pcbs.listen_pcbs; lpcb != NULL; lpcb = lpcb->next) {
+      if (lpcb->local_port == tcphdr->dest) {
+#if SO_REUSE
+        if (ip_addr_cmp(&(lpcb->local_ip), &current_iphdr_dest)) {
+          /* found an exact match */
+          break;
+        } else if(ip_addr_isany(&(lpcb->local_ip))) {
+          /* found an ANY-match */
+          lpcb_any = lpcb;
+          lpcb_prev = prev;
+        }
+#else /* SO_REUSE */
+        if (ip_addr_cmp(&(lpcb->local_ip), &current_iphdr_dest) ||
+            ip_addr_isany(&(lpcb->local_ip))) {
+          /* found a match */
+          break;
+        }
+#endif /* SO_REUSE */
+      }
+      prev = (struct tcp_pcb *)lpcb;
+    }
+#if SO_REUSE
+    /* first try specific local IP */
+    if (lpcb == NULL) {
+      /* only pass to ANY if no specific local IP has been found */
+      lpcb = lpcb_any;
+      prev = lpcb_prev;
+    }
+#endif /* SO_REUSE */
+    if (lpcb != NULL) {
+      /* Move this PCB to the front of the list so that subsequent
+         lookups will be faster (we exploit locality in TCP segment
+         arrivals). */
+      if (prev != NULL) {
+        ((struct tcp_pcb_listen *)prev)->next = lpcb->next;
+              /* our successor is the remainder of the listening list */
+        lpcb->next = tcp_listen_pcbs.listen_pcbs;
+              /* put this listening pcb at the head of the listening list */
+        tcp_listen_pcbs.listen_pcbs = lpcb;
+      }
+    
+      LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_input: packed for LISTENing connection.\n"));
+      tcp_listen_input(lpcb);
+      pbuf_free(p);
+      return;
+    }
+  }
+
+#if TCP_INPUT_DEBUG
+  LWIP_DEBUGF(TCP_INPUT_DEBUG, ("+-+-+-+-+-+-+-+-+-+-+-+-+-+- tcp_input: flags "));
+  tcp_debug_print_flags(TCPH_FLAGS(tcphdr));
+  LWIP_DEBUGF(TCP_INPUT_DEBUG, ("-+-+-+-+-+-+-+-+-+-+-+-+-+-+\n"));
+#endif /* TCP_INPUT_DEBUG */
+
+
+  if (pcb != NULL) {
+    /* The incoming segment belongs to a connection. */
+#if TCP_INPUT_DEBUG
+#if TCP_DEBUG
+    tcp_debug_print_state(pcb->state);
+#endif /* TCP_DEBUG */
+#endif /* TCP_INPUT_DEBUG */
+
+    /* Set up a tcp_seg structure. */
+    inseg.next = NULL;
+    inseg.len = p->tot_len;
+    inseg.dataptr = p->payload;
+    inseg.p = p;
+    inseg.tcphdr = tcphdr;
+
+    recv_data = NULL;
+    recv_flags = 0;
+
+    /* If there is data which was previously "refused" by upper layer */
+    if (pcb->refused_data != NULL) {
+      /* Notify again application with data previously received. */
+      LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_input: notify kept packet\n"));
+      TCP_EVENT_RECV(pcb, pcb->refused_data, ERR_OK, err);
+      if (err == ERR_OK) {
+        pcb->refused_data = NULL;
+      } else {
+        /* if err == ERR_ABRT, 'pcb' is already deallocated */
+        /* drop incoming packets, because pcb is "full" */
+        LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_input: drop incoming packets, because pcb is \"full\"\n"));
+        TCP_STATS_INC(tcp.drop);
+        snmp_inc_tcpinerrs();
+        pbuf_free(p);
+        return;
+      }
+    }
+    tcp_input_pcb = pcb;
+    err = tcp_process(pcb);
+    /* A return value of ERR_ABRT means that tcp_abort() was called
+       and that the pcb has been freed. If so, we don't do anything. */
+    if (err != ERR_ABRT) {
+      if (recv_flags & TF_RESET) {
+        /* TF_RESET means that the connection was reset by the other
+           end. We then call the error callback to inform the
+           application that the connection is dead before we
+           deallocate the PCB. */
+        TCP_EVENT_ERR(pcb->errf, pcb->callback_arg, ERR_RST);
+        tcp_pcb_remove(&tcp_active_pcbs, pcb);
+        memp_free(MEMP_TCP_PCB, pcb);
+      } else if (recv_flags & TF_CLOSED) {
+        /* The connection has been closed and we will deallocate the
+           PCB. */
+        tcp_pcb_remove(&tcp_active_pcbs, pcb);
+        memp_free(MEMP_TCP_PCB, pcb);
+      } else {
+        err = ERR_OK;
+        /* If the application has registered a "sent" function to be
+           called when new send buffer space is available, we call it
+           now. */
+        if (pcb->acked > 0) {
+          TCP_EVENT_SENT(pcb, pcb->acked, err);
+          if (err == ERR_ABRT) {
+            goto aborted;
+          }
+        }
+
+        if (recv_data != NULL) {
+          if (pcb->flags & TF_RXCLOSED) {
+            /* received data although already closed -> abort (send RST) to
+               notify the remote host that not all data has been processed */
+            pbuf_free(recv_data);
+            tcp_abort(pcb);
+            goto aborted;
+          }
+          if (flags & TCP_PSH) {
+            recv_data->flags |= PBUF_FLAG_PUSH;
+          }
+
+          /* Notify application that data has been received. */
+          TCP_EVENT_RECV(pcb, recv_data, ERR_OK, err);
+          if (err == ERR_ABRT) {
+            goto aborted;
+          }
+
+          /* If the upper layer can't receive this data, store it */
+          if (err != ERR_OK) {
+            pcb->refused_data = recv_data;
+            LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_input: keep incoming packet, because pcb is \"full\"\n"));
+          }
+        }
+
+        /* If a FIN segment was received, we call the callback
+           function with a NULL buffer to indicate EOF. */
+        if (recv_flags & TF_GOT_FIN) {
+          /* correct rcv_wnd as the application won't call tcp_recved()
+             for the FIN's seqno */
+          if (pcb->rcv_wnd != TCP_WND) {
+            pcb->rcv_wnd++;
+          }
+          TCP_EVENT_CLOSED(pcb, err);
+          if (err == ERR_ABRT) {
+            goto aborted;
+          }
+        }
+
+        tcp_input_pcb = NULL;
+        /* Try to send something out. */
+        tcp_output(pcb);
+#if TCP_INPUT_DEBUG
+#if TCP_DEBUG
+        tcp_debug_print_state(pcb->state);
+#endif /* TCP_DEBUG */
+#endif /* TCP_INPUT_DEBUG */
+      }
+    }
+    /* Jump target if pcb has been aborted in a callback (by calling tcp_abort()).
+       Below this line, 'pcb' may not be dereferenced! */
+aborted:
+    tcp_input_pcb = NULL;
+    recv_data = NULL;
+
+    /* give up our reference to inseg.p */
+    if (inseg.p != NULL)
+    {
+      pbuf_free(inseg.p);
+      inseg.p = NULL;
+    }
+  } else {
+
+    /* If no matching PCB was found, send a TCP RST (reset) to the
+       sender. */
+    LWIP_DEBUGF(TCP_RST_DEBUG, ("tcp_input: no PCB match found, resetting.\n"));
+    if (!(TCPH_FLAGS(tcphdr) & TCP_RST)) {
+      TCP_STATS_INC(tcp.proterr);
+      TCP_STATS_INC(tcp.drop);
+      tcp_rst(ackno, seqno + tcplen,
+        ip_current_dest_addr(), ip_current_src_addr(),
+        tcphdr->dest, tcphdr->src);
+    }
+    pbuf_free(p);
+  }
+
+  LWIP_ASSERT("tcp_input: tcp_pcbs_sane()", tcp_pcbs_sane());
+  PERF_STOP("tcp_input");
+}
+
+/**
+ * Called by tcp_input() when a segment arrives for a listening
+ * connection (from tcp_input()).
+ *
+ * @param pcb the tcp_pcb_listen for which a segment arrived
+ * @return ERR_OK if the segment was processed
+ *         another err_t on error
+ *
+ * @note the return value is not (yet?) used in tcp_input()
+ * @note the segment which arrived is saved in global variables, therefore only the pcb
+ *       involved is passed as a parameter to this function
+ */
+static err_t
+tcp_listen_input(struct tcp_pcb_listen *pcb)
+{
+  struct tcp_pcb *npcb;
+  err_t rc;
+
+  /* In the LISTEN state, we check for incoming SYN segments,
+     creates a new PCB, and responds with a SYN|ACK. */
+  if (flags & TCP_ACK) {
+    /* For incoming segments with the ACK flag set, respond with a
+       RST. */
+    LWIP_DEBUGF(TCP_RST_DEBUG, ("tcp_listen_input: ACK in LISTEN, sending reset\n"));
+    tcp_rst(ackno + 1, seqno + tcplen,
+      ip_current_dest_addr(), ip_current_src_addr(),
+      tcphdr->dest, tcphdr->src);
+  } else if (flags & TCP_SYN) {
+    LWIP_DEBUGF(TCP_DEBUG, ("TCP connection request %"U16_F" -> %"U16_F".\n", tcphdr->src, tcphdr->dest));
+#if TCP_LISTEN_BACKLOG
+    if (pcb->accepts_pending >= pcb->backlog) {
+      LWIP_DEBUGF(TCP_DEBUG, ("tcp_listen_input: listen backlog exceeded for port %"U16_F"\n", tcphdr->dest));
+      return ERR_ABRT;
+    }
+#endif /* TCP_LISTEN_BACKLOG */
+    npcb = tcp_alloc(pcb->prio);
+    /* If a new PCB could not be created (probably due to lack of memory),
+       we don't do anything, but rely on the sender will retransmit the
+       SYN at a time when we have more memory available. */
+    if (npcb == NULL) {
+      LWIP_DEBUGF(TCP_DEBUG, ("tcp_listen_input: could not allocate PCB\n"));
+      TCP_STATS_INC(tcp.memerr);
+      return ERR_MEM;
+    }
+#if TCP_LISTEN_BACKLOG
+    pcb->accepts_pending++;
+#endif /* TCP_LISTEN_BACKLOG */
+    /* Set up the new PCB. */
+    ip_addr_copy(npcb->local_ip, current_iphdr_dest);
+    npcb->local_port = pcb->local_port;
+    ip_addr_copy(npcb->remote_ip, current_iphdr_src);
+    npcb->remote_port = tcphdr->src;
+    npcb->state = SYN_RCVD;
+    npcb->rcv_nxt = seqno + 1;
+    npcb->rcv_ann_right_edge = npcb->rcv_nxt;
+    npcb->snd_wnd = tcphdr->wnd;
+    npcb->ssthresh = npcb->snd_wnd;
+    npcb->snd_wl1 = seqno - 1;/* initialise to seqno-1 to force window update */
+    npcb->callback_arg = pcb->callback_arg;
+#if LWIP_CALLBACK_API
+    npcb->accept = pcb->accept;
+#endif /* LWIP_CALLBACK_API */
+    /* inherit socket options */
+    npcb->so_options = pcb->so_options & SOF_INHERITED;
+    /* Register the new PCB so that we can begin receiving segments
+       for it. */
+    TCP_REG(&tcp_active_pcbs, npcb);
+
+    /* Parse any options in the SYN. */
+    tcp_parseopt(npcb);
+#if TCP_CALCULATE_EFF_SEND_MSS
+    npcb->mss = tcp_eff_send_mss(npcb->mss, &(npcb->remote_ip));
+#endif /* TCP_CALCULATE_EFF_SEND_MSS */
+
+    snmp_inc_tcppassiveopens();
+
+    /* Send a SYN|ACK together with the MSS option. */
+    rc = tcp_enqueue_flags(npcb, TCP_SYN | TCP_ACK);
+    if (rc != ERR_OK) {
+      tcp_abandon(npcb, 0);
+      return rc;
+    }
+    return tcp_output(npcb);
+  }
+  return ERR_OK;
+}
+
+/**
+ * Called by tcp_input() when a segment arrives for a connection in
+ * TIME_WAIT.
+ *
+ * @param pcb the tcp_pcb for which a segment arrived
+ *
+ * @note the segment which arrived is saved in global variables, therefore only the pcb
+ *       involved is passed as a parameter to this function
+ */
+static err_t
+tcp_timewait_input(struct tcp_pcb *pcb)
+{
+  /* RFC 1337: in TIME_WAIT, ignore RST and ACK FINs + any 'acceptable' segments */
+  /* RFC 793 3.9 Event Processing - Segment Arrives:
+   * - first check sequence number - we skip that one in TIME_WAIT (always
+   *   acceptable since we only send ACKs)
+   * - second check the RST bit (... return) */
+  if (flags & TCP_RST)  {
+    return ERR_OK;
+  }
+  /* - fourth, check the SYN bit, */
+  if (flags & TCP_SYN) {
+    /* If an incoming segment is not acceptable, an acknowledgment
+       should be sent in reply */
+    if (TCP_SEQ_BETWEEN(seqno, pcb->rcv_nxt, pcb->rcv_nxt+pcb->rcv_wnd)) {
+      /* If the SYN is in the window it is an error, send a reset */
+      tcp_rst(ackno, seqno + tcplen, ip_current_dest_addr(), ip_current_src_addr(),
+        tcphdr->dest, tcphdr->src);
+      return ERR_OK;
+    }
+  } else if (flags & TCP_FIN) {
+    /* - eighth, check the FIN bit: Remain in the TIME-WAIT state.
+         Restart the 2 MSL time-wait timeout.*/
+    pcb->tmr = tcp_ticks;
+  }
+
+  if ((tcplen > 0))  {
+    /* Acknowledge data, FIN or out-of-window SYN */
+    pcb->flags |= TF_ACK_NOW;
+    return tcp_output(pcb);
+  }
+  return ERR_OK;
+}
+
+/**
+ * Implements the TCP state machine. Called by tcp_input. In some
+ * states tcp_receive() is called to receive data. The tcp_seg
+ * argument will be freed by the caller (tcp_input()) unless the
+ * recv_data pointer in the pcb is set.
+ *
+ * @param pcb the tcp_pcb for which a segment arrived
+ *
+ * @note the segment which arrived is saved in global variables, therefore only the pcb
+ *       involved is passed as a parameter to this function
+ */
+static err_t
+tcp_process(struct tcp_pcb *pcb)
+{
+  struct tcp_seg *rseg;
+  u8_t acceptable = 0;
+  err_t err;
+
+  err = ERR_OK;
+
+  /* Process incoming RST segments. */
+  if (flags & TCP_RST) {
+    /* First, determine if the reset is acceptable. */
+    if (pcb->state == SYN_SENT) {
+      if (ackno == pcb->snd_nxt) {
+        acceptable = 1;
+      }
+    } else {
+      if (TCP_SEQ_BETWEEN(seqno, pcb->rcv_nxt, 
+                          pcb->rcv_nxt+pcb->rcv_wnd)) {
+        acceptable = 1;
+      }
+    }
+
+    if (acceptable) {
+      LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_process: Connection RESET\n"));
+      LWIP_ASSERT("tcp_input: pcb->state != CLOSED", pcb->state != CLOSED);
+      recv_flags |= TF_RESET;
+      pcb->flags &= ~TF_ACK_DELAY;
+      return ERR_RST;
+    } else {
+      LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_process: unacceptable reset seqno %"U32_F" rcv_nxt %"U32_F"\n",
+       seqno, pcb->rcv_nxt));
+      LWIP_DEBUGF(TCP_DEBUG, ("tcp_process: unacceptable reset seqno %"U32_F" rcv_nxt %"U32_F"\n",
+       seqno, pcb->rcv_nxt));
+      return ERR_OK;
+    }
+  }
+
+  if ((flags & TCP_SYN) && (pcb->state != SYN_SENT && pcb->state != SYN_RCVD)) { 
+    /* Cope with new connection attempt after remote end crashed */
+    tcp_ack_now(pcb);
+    return ERR_OK;
+  }
+  
+  if ((pcb->flags & TF_RXCLOSED) == 0) {
+    /* Update the PCB (in)activity timer unless rx is closed (see tcp_shutdown) */
+    pcb->tmr = tcp_ticks;
+  }
+  pcb->keep_cnt_sent = 0;
+
+  tcp_parseopt(pcb);
+
+  /* Do different things depending on the TCP state. */
+  switch (pcb->state) {
+  case SYN_SENT:
+    LWIP_DEBUGF(TCP_INPUT_DEBUG, ("SYN-SENT: ackno %"U32_F" pcb->snd_nxt %"U32_F" unacked %"U32_F"\n", ackno,
+     pcb->snd_nxt, ntohl(pcb->unacked->tcphdr->seqno)));
+    /* received SYN ACK with expected sequence number? */
+    if ((flags & TCP_ACK) && (flags & TCP_SYN)
+        && ackno == ntohl(pcb->unacked->tcphdr->seqno) + 1) {
+      pcb->snd_buf++;
+      pcb->rcv_nxt = seqno + 1;
+      pcb->rcv_ann_right_edge = pcb->rcv_nxt;
+      pcb->lastack = ackno;
+      pcb->snd_wnd = tcphdr->wnd;
+      pcb->snd_wl1 = seqno - 1; /* initialise to seqno - 1 to force window update */
+      pcb->state = ESTABLISHED;
+
+#if TCP_CALCULATE_EFF_SEND_MSS
+      pcb->mss = tcp_eff_send_mss(pcb->mss, &(pcb->remote_ip));
+#endif /* TCP_CALCULATE_EFF_SEND_MSS */
+
+      /* Set ssthresh again after changing pcb->mss (already set in tcp_connect
+       * but for the default value of pcb->mss) */
+      pcb->ssthresh = pcb->mss * 10;
+
+      pcb->cwnd = ((pcb->cwnd == 1) ? (pcb->mss * 2) : pcb->mss);
+      LWIP_ASSERT("pcb->snd_queuelen > 0", (pcb->snd_queuelen > 0));
+      --pcb->snd_queuelen;
+      LWIP_DEBUGF(TCP_QLEN_DEBUG, ("tcp_process: SYN-SENT --queuelen %"U16_F"\n", (u16_t)pcb->snd_queuelen));
+      rseg = pcb->unacked;
+      pcb->unacked = rseg->next;
+
+      /* If there's nothing left to acknowledge, stop the retransmit
+         timer, otherwise reset it to start again */
+      if(pcb->unacked == NULL)
+        pcb->rtime = -1;
+      else {
+        pcb->rtime = 0;
+        pcb->nrtx = 0;
+      }
+
+      tcp_seg_free(rseg);
+
+      /* Call the user specified function to call when sucessfully
+       * connected. */
+      TCP_EVENT_CONNECTED(pcb, ERR_OK, err);
+      if (err == ERR_ABRT) {
+        return ERR_ABRT;
+      }
+      tcp_ack_now(pcb);
+    }
+    /* received ACK? possibly a half-open connection */
+    else if (flags & TCP_ACK) {
+      /* send a RST to bring the other side in a non-synchronized state. */
+      tcp_rst(ackno, seqno + tcplen, ip_current_dest_addr(), ip_current_src_addr(),
+        tcphdr->dest, tcphdr->src);
+    }
+    break;
+  case SYN_RCVD:
+    if (flags & TCP_ACK) {
+      /* expected ACK number? */
+      if (TCP_SEQ_BETWEEN(ackno, pcb->lastack+1, pcb->snd_nxt)) {
+        u16_t old_cwnd;
+        pcb->state = ESTABLISHED;
+        LWIP_DEBUGF(TCP_DEBUG, ("TCP connection established %"U16_F" -> %"U16_F".\n", inseg.tcphdr->src, inseg.tcphdr->dest));
+#if LWIP_CALLBACK_API
+        LWIP_ASSERT("pcb->accept != NULL", pcb->accept != NULL);
+#endif
+        /* Call the accept function. */
+        TCP_EVENT_ACCEPT(pcb, ERR_OK, err);
+        if (err != ERR_OK) {
+          /* If the accept function returns with an error, we abort
+           * the connection. */
+          /* Already aborted? */
+          if (err != ERR_ABRT) {
+            tcp_abort(pcb);
+          }
+          return ERR_ABRT;
+        }
+        old_cwnd = pcb->cwnd;
+        /* If there was any data contained within this ACK,
+         * we'd better pass it on to the application as well. */
+        tcp_receive(pcb);
+
+        /* Prevent ACK for SYN to generate a sent event */
+        if (pcb->acked != 0) {
+          pcb->acked--;
+        }
+
+        pcb->cwnd = ((old_cwnd == 1) ? (pcb->mss * 2) : pcb->mss);
+
+        if (recv_flags & TF_GOT_FIN) {
+          tcp_ack_now(pcb);
+          pcb->state = CLOSE_WAIT;
+        }
+      } else {
+        /* incorrect ACK number, send RST */
+        tcp_rst(ackno, seqno + tcplen, ip_current_dest_addr(), ip_current_src_addr(),
+                tcphdr->dest, tcphdr->src);
+      }
+    } else if ((flags & TCP_SYN) && (seqno == pcb->rcv_nxt - 1)) {
+      /* Looks like another copy of the SYN - retransmit our SYN-ACK */
+      tcp_rexmit(pcb);
+    }
+    break;
+  case CLOSE_WAIT:
+    /* FALLTHROUGH */
+  case ESTABLISHED:
+    tcp_receive(pcb);
+    if (recv_flags & TF_GOT_FIN) { /* passive close */
+      tcp_ack_now(pcb);
+      pcb->state = CLOSE_WAIT;
+    }
+    break;
+  case FIN_WAIT_1:
+    tcp_receive(pcb);
+    if (recv_flags & TF_GOT_FIN) {
+      if ((flags & TCP_ACK) && (ackno == pcb->snd_nxt)) {
+        LWIP_DEBUGF(TCP_DEBUG,
+          ("TCP connection closed: FIN_WAIT_1 %"U16_F" -> %"U16_F".\n", inseg.tcphdr->src, inseg.tcphdr->dest));
+        tcp_ack_now(pcb);
+        tcp_pcb_purge(pcb);
+        TCP_RMV(&tcp_active_pcbs, pcb);
+        pcb->state = TIME_WAIT;
+        TCP_REG(&tcp_tw_pcbs, pcb);
+      } else {
+        tcp_ack_now(pcb);
+        pcb->state = CLOSING;
+      }
+    } else if ((flags & TCP_ACK) && (ackno == pcb->snd_nxt)) {
+      pcb->state = FIN_WAIT_2;
+    }
+    break;
+  case FIN_WAIT_2:
+    tcp_receive(pcb);
+    if (recv_flags & TF_GOT_FIN) {
+      LWIP_DEBUGF(TCP_DEBUG, ("TCP connection closed: FIN_WAIT_2 %"U16_F" -> %"U16_F".\n", inseg.tcphdr->src, inseg.tcphdr->dest));
+      tcp_ack_now(pcb);
+      tcp_pcb_purge(pcb);
+      TCP_RMV(&tcp_active_pcbs, pcb);
+      pcb->state = TIME_WAIT;
+      TCP_REG(&tcp_tw_pcbs, pcb);
+    }
+    break;
+  case CLOSING:
+    tcp_receive(pcb);
+    if (flags & TCP_ACK && ackno == pcb->snd_nxt) {
+      LWIP_DEBUGF(TCP_DEBUG, ("TCP connection closed: CLOSING %"U16_F" -> %"U16_F".\n", inseg.tcphdr->src, inseg.tcphdr->dest));
+      tcp_pcb_purge(pcb);
+      TCP_RMV(&tcp_active_pcbs, pcb);
+      pcb->state = TIME_WAIT;
+      TCP_REG(&tcp_tw_pcbs, pcb);
+    }
+    break;
+  case LAST_ACK:
+    tcp_receive(pcb);
+    if (flags & TCP_ACK && ackno == pcb->snd_nxt) {
+      LWIP_DEBUGF(TCP_DEBUG, ("TCP connection closed: LAST_ACK %"U16_F" -> %"U16_F".\n", inseg.tcphdr->src, inseg.tcphdr->dest));
+      /* bugfix #21699: don't set pcb->state to CLOSED here or we risk leaking segments */
+      recv_flags |= TF_CLOSED;
+    }
+    break;
+  default:
+    break;
+  }
+  return ERR_OK;
+}
+
+#if TCP_QUEUE_OOSEQ
+/**
+ * Insert segment into the list (segments covered with new one will be deleted)
+ *
+ * Called from tcp_receive()
+ */
+static void
+tcp_oos_insert_segment(struct tcp_seg *cseg, struct tcp_seg *next)
+{
+  struct tcp_seg *old_seg;
+
+  if (TCPH_FLAGS(cseg->tcphdr) & TCP_FIN) {
+    /* received segment overlaps all following segments */
+    tcp_segs_free(next);
+    next = NULL;
+  }
+  else {
+    /* delete some following segments
+       oos queue may have segments with FIN flag */
+    while (next &&
+           TCP_SEQ_GEQ((seqno + cseg->len),
+                      (next->tcphdr->seqno + next->len))) {
+      /* cseg with FIN already processed */
+      if (TCPH_FLAGS(next->tcphdr) & TCP_FIN) {
+        TCPH_SET_FLAG(cseg->tcphdr, TCP_FIN);
+      }
+      old_seg = next;
+      next = next->next;
+      tcp_seg_free(old_seg);
+    }
+    if (next &&
+        TCP_SEQ_GT(seqno + cseg->len, next->tcphdr->seqno)) {
+      /* We need to trim the incoming segment. */
+      cseg->len = (u16_t)(next->tcphdr->seqno - seqno);
+      pbuf_realloc(cseg->p, cseg->len);
+    }
+  }
+  cseg->next = next;
+}
+#endif /* TCP_QUEUE_OOSEQ */
+
+/**
+ * Called by tcp_process. Checks if the given segment is an ACK for outstanding
+ * data, and if so frees the memory of the buffered data. Next, is places the
+ * segment on any of the receive queues (pcb->recved or pcb->ooseq). If the segment
+ * is buffered, the pbuf is referenced by pbuf_ref so that it will not be freed until
+ * i it has been removed from the buffer.
+ *
+ * If the incoming segment constitutes an ACK for a segment that was used for RTT
+ * estimation, the RTT is estimated here as well.
+ *
+ * Called from tcp_process().
+ */
+static void
+tcp_receive(struct tcp_pcb *pcb)
+{
+  struct tcp_seg *next;
+#if TCP_QUEUE_OOSEQ
+  struct tcp_seg *prev, *cseg;
+#endif /* TCP_QUEUE_OOSEQ */
+  struct pbuf *p;
+  s32_t off;
+  s16_t m;
+  u32_t right_wnd_edge;
+  u16_t new_tot_len;
+  int found_dupack = 0;
+
+  if (flags & TCP_ACK) {
+    right_wnd_edge = pcb->snd_wnd + pcb->snd_wl2;
+
+    /* Update window. */
+    if (TCP_SEQ_LT(pcb->snd_wl1, seqno) ||
+       (pcb->snd_wl1 == seqno && TCP_SEQ_LT(pcb->snd_wl2, ackno)) ||
+       (pcb->snd_wl2 == ackno && tcphdr->wnd > pcb->snd_wnd)) {
+      pcb->snd_wnd = tcphdr->wnd;
+      pcb->snd_wl1 = seqno;
+      pcb->snd_wl2 = ackno;
+      if (pcb->snd_wnd > 0 && pcb->persist_backoff > 0) {
+          pcb->persist_backoff = 0;
+      }
+      LWIP_DEBUGF(TCP_WND_DEBUG, ("tcp_receive: window update %"U16_F"\n", pcb->snd_wnd));
+#if TCP_WND_DEBUG
+    } else {
+      if (pcb->snd_wnd != tcphdr->wnd) {
+        LWIP_DEBUGF(TCP_WND_DEBUG, 
+                    ("tcp_receive: no window update lastack %"U32_F" ackno %"
+                     U32_F" wl1 %"U32_F" seqno %"U32_F" wl2 %"U32_F"\n",
+                     pcb->lastack, ackno, pcb->snd_wl1, seqno, pcb->snd_wl2));
+      }
+#endif /* TCP_WND_DEBUG */
+    }
+
+    /* (From Stevens TCP/IP Illustrated Vol II, p970.) Its only a
+     * duplicate ack if:
+     * 1) It doesn't ACK new data 
+     * 2) length of received packet is zero (i.e. no payload) 
+     * 3) the advertised window hasn't changed 
+     * 4) There is outstanding unacknowledged data (retransmission timer running)
+     * 5) The ACK is == biggest ACK sequence number so far seen (snd_una)
+     * 
+     * If it passes all five, should process as a dupack: 
+     * a) dupacks < 3: do nothing 
+     * b) dupacks == 3: fast retransmit 
+     * c) dupacks > 3: increase cwnd 
+     * 
+     * If it only passes 1-3, should reset dupack counter (and add to
+     * stats, which we don't do in lwIP)
+     *
+     * If it only passes 1, should reset dupack counter
+     *
+     */
+
+    /* Clause 1 */
+    if (TCP_SEQ_LEQ(ackno, pcb->lastack)) {
+      pcb->acked = 0;
+      /* Clause 2 */
+      if (tcplen == 0) {
+        /* Clause 3 */
+        if (pcb->snd_wl2 + pcb->snd_wnd == right_wnd_edge){
+          /* Clause 4 */
+          if (pcb->rtime >= 0) {
+            /* Clause 5 */
+            if (pcb->lastack == ackno) {
+              found_dupack = 1;
+              if (pcb->dupacks + 1 > pcb->dupacks)
+                ++pcb->dupacks;
+              if (pcb->dupacks > 3) {
+                /* Inflate the congestion window, but not if it means that
+                   the value overflows. */
+                if ((u16_t)(pcb->cwnd + pcb->mss) > pcb->cwnd) {
+                  pcb->cwnd += pcb->mss;
+                }
+              } else if (pcb->dupacks == 3) {
+                /* Do fast retransmit */
+                tcp_rexmit_fast(pcb);
+              }
+            }
+          }
+        }
+      }
+      /* If Clause (1) or more is true, but not a duplicate ack, reset
+       * count of consecutive duplicate acks */
+      if (!found_dupack) {
+        pcb->dupacks = 0;
+      }
+    } else if (TCP_SEQ_BETWEEN(ackno, pcb->lastack+1, pcb->snd_nxt)){
+      /* We come here when the ACK acknowledges new data. */
+
+      /* Reset the "IN Fast Retransmit" flag, since we are no longer
+         in fast retransmit. Also reset the congestion window to the
+         slow start threshold. */
+      if (pcb->flags & TF_INFR) {
+        pcb->flags &= ~TF_INFR;
+        pcb->cwnd = pcb->ssthresh;
+      }
+
+      /* Reset the number of retransmissions. */
+      pcb->nrtx = 0;
+
+      /* Reset the retransmission time-out. */
+      pcb->rto = (pcb->sa >> 3) + pcb->sv;
+
+      /* Update the send buffer space. Diff between the two can never exceed 64K? */
+      pcb->acked = (u16_t)(ackno - pcb->lastack);
+
+      pcb->snd_buf += pcb->acked;
+
+      /* Reset the fast retransmit variables. */
+      pcb->dupacks = 0;
+      pcb->lastack = ackno;
+
+      /* Update the congestion control variables (cwnd and
+         ssthresh). */
+      if (pcb->state >= ESTABLISHED) {
+        if (pcb->cwnd < pcb->ssthresh) {
+          if ((u16_t)(pcb->cwnd + pcb->mss) > pcb->cwnd) {
+            pcb->cwnd += pcb->mss;
+          }
+          LWIP_DEBUGF(TCP_CWND_DEBUG, ("tcp_receive: slow start cwnd %"U16_F"\n", pcb->cwnd));
+        } else {
+          u16_t new_cwnd = (pcb->cwnd + pcb->mss * pcb->mss / pcb->cwnd);
+          if (new_cwnd > pcb->cwnd) {
+            pcb->cwnd = new_cwnd;
+          }
+          LWIP_DEBUGF(TCP_CWND_DEBUG, ("tcp_receive: congestion avoidance cwnd %"U16_F"\n", pcb->cwnd));
+        }
+      }
+      LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_receive: ACK for %"U32_F", unacked->seqno %"U32_F":%"U32_F"\n",
+                                    ackno,
+                                    pcb->unacked != NULL?
+                                    ntohl(pcb->unacked->tcphdr->seqno): 0,
+                                    pcb->unacked != NULL?
+                                    ntohl(pcb->unacked->tcphdr->seqno) + TCP_TCPLEN(pcb->unacked): 0));
+
+      /* Remove segment from the unacknowledged list if the incoming
+         ACK acknowlegdes them. */
+      while (pcb->unacked != NULL &&
+             TCP_SEQ_LEQ(ntohl(pcb->unacked->tcphdr->seqno) +
+                         TCP_TCPLEN(pcb->unacked), ackno)) {
+        LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_receive: removing %"U32_F":%"U32_F" from pcb->unacked\n",
+                                      ntohl(pcb->unacked->tcphdr->seqno),
+                                      ntohl(pcb->unacked->tcphdr->seqno) +
+                                      TCP_TCPLEN(pcb->unacked)));
+
+        next = pcb->unacked;
+        pcb->unacked = pcb->unacked->next;
+
+        LWIP_DEBUGF(TCP_QLEN_DEBUG, ("tcp_receive: queuelen %"U16_F" ... ", (u16_t)pcb->snd_queuelen));
+        LWIP_ASSERT("pcb->snd_queuelen >= pbuf_clen(next->p)", (pcb->snd_queuelen >= pbuf_clen(next->p)));
+        /* Prevent ACK for FIN to generate a sent event */
+        if ((pcb->acked != 0) && ((TCPH_FLAGS(next->tcphdr) & TCP_FIN) != 0)) {
+          pcb->acked--;
+        }
+
+        pcb->snd_queuelen -= pbuf_clen(next->p);
+        tcp_seg_free(next);
+
+        LWIP_DEBUGF(TCP_QLEN_DEBUG, ("%"U16_F" (after freeing unacked)\n", (u16_t)pcb->snd_queuelen));
+        if (pcb->snd_queuelen != 0) {
+          LWIP_ASSERT("tcp_receive: valid queue length", pcb->unacked != NULL ||
+                      pcb->unsent != NULL);
+        }
+      }
+
+      /* If there's nothing left to acknowledge, stop the retransmit
+         timer, otherwise reset it to start again */
+      if(pcb->unacked == NULL)
+        pcb->rtime = -1;
+      else
+        pcb->rtime = 0;
+
+      pcb->polltmr = 0;
+    } else {
+      /* Fix bug bug #21582: out of sequence ACK, didn't really ack anything */
+      pcb->acked = 0;
+    }
+
+    /* We go through the ->unsent list to see if any of the segments
+       on the list are acknowledged by the ACK. This may seem
+       strange since an "unsent" segment shouldn't be acked. The
+       rationale is that lwIP puts all outstanding segments on the
+       ->unsent list after a retransmission, so these segments may
+       in fact have been sent once. */
+    while (pcb->unsent != NULL &&
+           TCP_SEQ_BETWEEN(ackno, ntohl(pcb->unsent->tcphdr->seqno) + 
+                           TCP_TCPLEN(pcb->unsent), pcb->snd_nxt)) {
+      LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_receive: removing %"U32_F":%"U32_F" from pcb->unsent\n",
+                                    ntohl(pcb->unsent->tcphdr->seqno), ntohl(pcb->unsent->tcphdr->seqno) +
+                                    TCP_TCPLEN(pcb->unsent)));
+
+      next = pcb->unsent;
+      pcb->unsent = pcb->unsent->next;
+      LWIP_DEBUGF(TCP_QLEN_DEBUG, ("tcp_receive: queuelen %"U16_F" ... ", (u16_t)pcb->snd_queuelen));
+      LWIP_ASSERT("pcb->snd_queuelen >= pbuf_clen(next->p)", (pcb->snd_queuelen >= pbuf_clen(next->p)));
+      /* Prevent ACK for FIN to generate a sent event */
+      if ((pcb->acked != 0) && ((TCPH_FLAGS(next->tcphdr) & TCP_FIN) != 0)) {
+        pcb->acked--;
+      }
+      pcb->snd_queuelen -= pbuf_clen(next->p);
+      tcp_seg_free(next);
+      LWIP_DEBUGF(TCP_QLEN_DEBUG, ("%"U16_F" (after freeing unsent)\n", (u16_t)pcb->snd_queuelen));
+      if (pcb->snd_queuelen != 0) {
+        LWIP_ASSERT("tcp_receive: valid queue length",
+          pcb->unacked != NULL || pcb->unsent != NULL);
+      }
+    }
+    /* End of ACK for new data processing. */
+
+    LWIP_DEBUGF(TCP_RTO_DEBUG, ("tcp_receive: pcb->rttest %"U32_F" rtseq %"U32_F" ackno %"U32_F"\n",
+                                pcb->rttest, pcb->rtseq, ackno));
+
+    /* RTT estimation calculations. This is done by checking if the
+       incoming segment acknowledges the segment we use to take a
+       round-trip time measurement. */
+    if (pcb->rttest && TCP_SEQ_LT(pcb->rtseq, ackno)) {
+      /* diff between this shouldn't exceed 32K since this are tcp timer ticks
+         and a round-trip shouldn't be that long... */
+      m = (s16_t)(tcp_ticks - pcb->rttest);
+
+      LWIP_DEBUGF(TCP_RTO_DEBUG, ("tcp_receive: experienced rtt %"U16_F" ticks (%"U16_F" msec).\n",
+                                  m, m * TCP_SLOW_INTERVAL));
+
+      /* This is taken directly from VJs original code in his paper */
+      m = m - (pcb->sa >> 3);
+      pcb->sa += m;
+      if (m < 0) {
+        m = -m;
+      }
+      m = m - (pcb->sv >> 2);
+      pcb->sv += m;
+      pcb->rto = (pcb->sa >> 3) + pcb->sv;
+
+      LWIP_DEBUGF(TCP_RTO_DEBUG, ("tcp_receive: RTO %"U16_F" (%"U16_F" milliseconds)\n",
+                                  pcb->rto, pcb->rto * TCP_SLOW_INTERVAL));
+
+      pcb->rttest = 0;
+    }
+  }
+
+  /* If the incoming segment contains data, we must process it
+     further. */
+  if (tcplen > 0) {
+    /* This code basically does three things:
+
+    +) If the incoming segment contains data that is the next
+    in-sequence data, this data is passed to the application. This
+    might involve trimming the first edge of the data. The rcv_nxt
+    variable and the advertised window are adjusted.
+
+    +) If the incoming segment has data that is above the next
+    sequence number expected (->rcv_nxt), the segment is placed on
+    the ->ooseq queue. This is done by finding the appropriate
+    place in the ->ooseq queue (which is ordered by sequence
+    number) and trim the segment in both ends if needed. An
+    immediate ACK is sent to indicate that we received an
+    out-of-sequence segment.
+
+    +) Finally, we check if the first segment on the ->ooseq queue
+    now is in sequence (i.e., if rcv_nxt >= ooseq->seqno). If
+    rcv_nxt > ooseq->seqno, we must trim the first edge of the
+    segment on ->ooseq before we adjust rcv_nxt. The data in the
+    segments that are now on sequence are chained onto the
+    incoming segment so that we only need to call the application
+    once.
+    */
+
+    /* First, we check if we must trim the first edge. We have to do
+       this if the sequence number of the incoming segment is less
+       than rcv_nxt, and the sequence number plus the length of the
+       segment is larger than rcv_nxt. */
+    /*    if (TCP_SEQ_LT(seqno, pcb->rcv_nxt)){
+          if (TCP_SEQ_LT(pcb->rcv_nxt, seqno + tcplen)) {*/
+    if (TCP_SEQ_BETWEEN(pcb->rcv_nxt, seqno + 1, seqno + tcplen - 1)){
+      /* Trimming the first edge is done by pushing the payload
+         pointer in the pbuf downwards. This is somewhat tricky since
+         we do not want to discard the full contents of the pbuf up to
+         the new starting point of the data since we have to keep the
+         TCP header which is present in the first pbuf in the chain.
+
+         What is done is really quite a nasty hack: the first pbuf in
+         the pbuf chain is pointed to by inseg.p. Since we need to be
+         able to deallocate the whole pbuf, we cannot change this
+         inseg.p pointer to point to any of the later pbufs in the
+         chain. Instead, we point the ->payload pointer in the first
+         pbuf to data in one of the later pbufs. We also set the
+         inseg.data pointer to point to the right place. This way, the
+         ->p pointer will still point to the first pbuf, but the
+         ->p->payload pointer will point to data in another pbuf.
+
+         After we are done with adjusting the pbuf pointers we must
+         adjust the ->data pointer in the seg and the segment
+         length.*/
+
+      off = pcb->rcv_nxt - seqno;
+      p = inseg.p;
+      LWIP_ASSERT("inseg.p != NULL", inseg.p);
+      LWIP_ASSERT("insane offset!", (off < 0x7fff));
+      if (inseg.p->len < off) {
+        LWIP_ASSERT("pbuf too short!", (((s32_t)inseg.p->tot_len) >= off));
+        new_tot_len = (u16_t)(inseg.p->tot_len - off);
+        while (p->len < off) {
+          off -= p->len;
+          /* KJM following line changed (with addition of new_tot_len var)
+             to fix bug #9076
+             inseg.p->tot_len -= p->len; */
+          p->tot_len = new_tot_len;
+          p->len = 0;
+          p = p->next;
+        }
+        if(pbuf_header(p, (s16_t)-off)) {
+          /* Do we need to cope with this failing?  Assert for now */
+          LWIP_ASSERT("pbuf_header failed", 0);
+        }
+      } else {
+        if(pbuf_header(inseg.p, (s16_t)-off)) {
+          /* Do we need to cope with this failing?  Assert for now */
+          LWIP_ASSERT("pbuf_header failed", 0);
+        }
+      }
+      /* KJM following line changed to use p->payload rather than inseg->p->payload
+         to fix bug #9076 */
+      inseg.dataptr = p->payload;
+      inseg.len -= (u16_t)(pcb->rcv_nxt - seqno);
+      inseg.tcphdr->seqno = seqno = pcb->rcv_nxt;
+    }
+    else {
+      if (TCP_SEQ_LT(seqno, pcb->rcv_nxt)){
+        /* the whole segment is < rcv_nxt */
+        /* must be a duplicate of a packet that has already been correctly handled */
+
+        LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_receive: duplicate seqno %"U32_F"\n", seqno));
+        tcp_ack_now(pcb);
+      }
+    }
+
+    /* The sequence number must be within the window (above rcv_nxt
+       and below rcv_nxt + rcv_wnd) in order to be further
+       processed. */
+    if (TCP_SEQ_BETWEEN(seqno, pcb->rcv_nxt, 
+                        pcb->rcv_nxt + pcb->rcv_wnd - 1)){
+      if (pcb->rcv_nxt == seqno) {
+        /* The incoming segment is the next in sequence. We check if
+           we have to trim the end of the segment and update rcv_nxt
+           and pass the data to the application. */
+        tcplen = TCP_TCPLEN(&inseg);
+
+        if (tcplen > pcb->rcv_wnd) {
+          LWIP_DEBUGF(TCP_INPUT_DEBUG, 
+                      ("tcp_receive: other end overran receive window"
+                       "seqno %"U32_F" len %"U16_F" right edge %"U32_F"\n",
+                       seqno, tcplen, pcb->rcv_nxt + pcb->rcv_wnd));
+          if (TCPH_FLAGS(inseg.tcphdr) & TCP_FIN) {
+            /* Must remove the FIN from the header as we're trimming 
+             * that byte of sequence-space from the packet */
+            TCPH_FLAGS_SET(inseg.tcphdr, TCPH_FLAGS(inseg.tcphdr) &~ TCP_FIN);
+          }
+          /* Adjust length of segment to fit in the window. */
+          inseg.len = pcb->rcv_wnd;
+          if (TCPH_FLAGS(inseg.tcphdr) & TCP_SYN) {
+            inseg.len -= 1;
+          }
+          pbuf_realloc(inseg.p, inseg.len);
+          tcplen = TCP_TCPLEN(&inseg);
+          LWIP_ASSERT("tcp_receive: segment not trimmed correctly to rcv_wnd\n",
+                      (seqno + tcplen) == (pcb->rcv_nxt + pcb->rcv_wnd));
+        }
+#if TCP_QUEUE_OOSEQ
+        /* Received in-sequence data, adjust ooseq data if:
+           - FIN has been received or
+           - inseq overlaps with ooseq */
+        if (pcb->ooseq != NULL) {
+          if (TCPH_FLAGS(inseg.tcphdr) & TCP_FIN) {
+            LWIP_DEBUGF(TCP_INPUT_DEBUG, 
+                        ("tcp_receive: received in-order FIN, binning ooseq queue\n"));
+            /* Received in-order FIN means anything that was received
+             * out of order must now have been received in-order, so
+             * bin the ooseq queue */
+            while (pcb->ooseq != NULL) {
+              struct tcp_seg *old_ooseq = pcb->ooseq;
+              pcb->ooseq = pcb->ooseq->next;
+              tcp_seg_free(old_ooseq);
+            }
+          }
+          else {
+            next = pcb->ooseq;
+            /* Remove all segments on ooseq that are covered by inseg already.
+             * FIN is copied from ooseq to inseg if present. */
+            while (next &&
+                   TCP_SEQ_GEQ(seqno + tcplen,
+                               next->tcphdr->seqno + next->len)) {
+              /* inseg cannot have FIN here (already processed above) */
+              if (TCPH_FLAGS(next->tcphdr) & TCP_FIN &&
+                  (TCPH_FLAGS(inseg.tcphdr) & TCP_SYN) == 0) {
+                TCPH_SET_FLAG(inseg.tcphdr, TCP_FIN);
+                tcplen = TCP_TCPLEN(&inseg);
+              }
+              prev = next;
+              next = next->next;
+              tcp_seg_free(prev);
+            }
+            /* Now trim right side of inseg if it overlaps with the first
+             * segment on ooseq */
+            if (next &&
+                TCP_SEQ_GT(seqno + tcplen,
+                           next->tcphdr->seqno)) {
+              /* inseg cannot have FIN here (already processed above) */
+              inseg.len = (u16_t)(next->tcphdr->seqno - seqno);
+              if (TCPH_FLAGS(inseg.tcphdr) & TCP_SYN) {
+                inseg.len -= 1;
+              }
+              pbuf_realloc(inseg.p, inseg.len);
+              tcplen = TCP_TCPLEN(&inseg);
+              LWIP_ASSERT("tcp_receive: segment not trimmed correctly to ooseq queue\n",
+                          (seqno + tcplen) == next->tcphdr->seqno);
+            }
+            pcb->ooseq = next;
+          }
+        }
+#endif /* TCP_QUEUE_OOSEQ */
+
+        pcb->rcv_nxt = seqno + tcplen;
+
+        /* Update the receiver's (our) window. */
+        LWIP_ASSERT("tcp_receive: tcplen > rcv_wnd\n", pcb->rcv_wnd >= tcplen);
+        pcb->rcv_wnd -= tcplen;
+
+        tcp_update_rcv_ann_wnd(pcb);
+
+        /* If there is data in the segment, we make preparations to
+           pass this up to the application. The ->recv_data variable
+           is used for holding the pbuf that goes to the
+           application. The code for reassembling out-of-sequence data
+           chains its data on this pbuf as well.
+
+           If the segment was a FIN, we set the TF_GOT_FIN flag that will
+           be used to indicate to the application that the remote side has
+           closed its end of the connection. */
+        if (inseg.p->tot_len > 0) {
+          recv_data = inseg.p;
+          /* Since this pbuf now is the responsibility of the
+             application, we delete our reference to it so that we won't
+             (mistakingly) deallocate it. */
+          inseg.p = NULL;
+        }
+        if (TCPH_FLAGS(inseg.tcphdr) & TCP_FIN) {
+          LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_receive: received FIN.\n"));
+          recv_flags |= TF_GOT_FIN;
+        }
+
+#if TCP_QUEUE_OOSEQ
+        /* We now check if we have segments on the ->ooseq queue that
+           are now in sequence. */
+        while (pcb->ooseq != NULL &&
+               pcb->ooseq->tcphdr->seqno == pcb->rcv_nxt) {
+
+          cseg = pcb->ooseq;
+          seqno = pcb->ooseq->tcphdr->seqno;
+
+          pcb->rcv_nxt += TCP_TCPLEN(cseg);
+          LWIP_ASSERT("tcp_receive: ooseq tcplen > rcv_wnd\n",
+                      pcb->rcv_wnd >= TCP_TCPLEN(cseg));
+          pcb->rcv_wnd -= TCP_TCPLEN(cseg);
+
+          tcp_update_rcv_ann_wnd(pcb);
+
+          if (cseg->p->tot_len > 0) {
+            /* Chain this pbuf onto the pbuf that we will pass to
+               the application. */
+            if (recv_data) {
+              pbuf_cat(recv_data, cseg->p);
+            } else {
+              recv_data = cseg->p;
+            }
+            cseg->p = NULL;
+          }
+          if (TCPH_FLAGS(cseg->tcphdr) & TCP_FIN) {
+            LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_receive: dequeued FIN.\n"));
+            recv_flags |= TF_GOT_FIN;
+            if (pcb->state == ESTABLISHED) { /* force passive close or we can move to active close */
+              pcb->state = CLOSE_WAIT;
+            } 
+          }
+
+          pcb->ooseq = cseg->next;
+          tcp_seg_free(cseg);
+        }
+#endif /* TCP_QUEUE_OOSEQ */
+
+
+        /* Acknowledge the segment(s). */
+        tcp_ack(pcb);
+
+      } else {
+        /* We get here if the incoming segment is out-of-sequence. */
+        tcp_send_empty_ack(pcb);
+#if TCP_QUEUE_OOSEQ
+        /* We queue the segment on the ->ooseq queue. */
+        if (pcb->ooseq == NULL) {
+          pcb->ooseq = tcp_seg_copy(&inseg);
+        } else {
+          /* If the queue is not empty, we walk through the queue and
+             try to find a place where the sequence number of the
+             incoming segment is between the sequence numbers of the
+             previous and the next segment on the ->ooseq queue. That is
+             the place where we put the incoming segment. If needed, we
+             trim the second edges of the previous and the incoming
+             segment so that it will fit into the sequence.
+
+             If the incoming segment has the same sequence number as a
+             segment on the ->ooseq queue, we discard the segment that
+             contains less data. */
+
+          prev = NULL;
+          for(next = pcb->ooseq; next != NULL; next = next->next) {
+            if (seqno == next->tcphdr->seqno) {
+              /* The sequence number of the incoming segment is the
+                 same as the sequence number of the segment on
+                 ->ooseq. We check the lengths to see which one to
+                 discard. */
+              if (inseg.len > next->len) {
+                /* The incoming segment is larger than the old
+                   segment. We replace some segments with the new
+                   one. */
+                cseg = tcp_seg_copy(&inseg);
+                if (cseg != NULL) {
+                  if (prev != NULL) {
+                    prev->next = cseg;
+                  } else {
+                    pcb->ooseq = cseg;
+                  }
+                  tcp_oos_insert_segment(cseg, next);
+                }
+                break;
+              } else {
+                /* Either the lenghts are the same or the incoming
+                   segment was smaller than the old one; in either
+                   case, we ditch the incoming segment. */
+                break;
+              }
+            } else {
+              if (prev == NULL) {
+                if (TCP_SEQ_LT(seqno, next->tcphdr->seqno)) {
+                  /* The sequence number of the incoming segment is lower
+                     than the sequence number of the first segment on the
+                     queue. We put the incoming segment first on the
+                     queue. */
+                  cseg = tcp_seg_copy(&inseg);
+                  if (cseg != NULL) {
+                    pcb->ooseq = cseg;
+                    tcp_oos_insert_segment(cseg, next);
+                  }
+                  break;
+                }
+              } else {
+                /*if (TCP_SEQ_LT(prev->tcphdr->seqno, seqno) &&
+                  TCP_SEQ_LT(seqno, next->tcphdr->seqno)) {*/
+                if (TCP_SEQ_BETWEEN(seqno, prev->tcphdr->seqno+1, next->tcphdr->seqno-1)) {
+                  /* The sequence number of the incoming segment is in
+                     between the sequence numbers of the previous and
+                     the next segment on ->ooseq. We trim trim the previous
+                     segment, delete next segments that included in received segment
+                     and trim received, if needed. */
+                  cseg = tcp_seg_copy(&inseg);
+                  if (cseg != NULL) {
+                    if (TCP_SEQ_GT(prev->tcphdr->seqno + prev->len, seqno)) {
+                      /* We need to trim the prev segment. */
+                      prev->len = (u16_t)(seqno - prev->tcphdr->seqno);
+                      pbuf_realloc(prev->p, prev->len);
+                    }
+                    prev->next = cseg;
+                    tcp_oos_insert_segment(cseg, next);
+                  }
+                  break;
+                }
+              }
+              /* If the "next" segment is the last segment on the
+                 ooseq queue, we add the incoming segment to the end
+                 of the list. */
+              if (next->next == NULL &&
+                  TCP_SEQ_GT(seqno, next->tcphdr->seqno)) {
+                if (TCPH_FLAGS(next->tcphdr) & TCP_FIN) {
+                  /* segment "next" already contains all data */
+                  break;
+                }
+                next->next = tcp_seg_copy(&inseg);
+                if (next->next != NULL) {
+                  if (TCP_SEQ_GT(next->tcphdr->seqno + next->len, seqno)) {
+                    /* We need to trim the last segment. */
+                    next->len = (u16_t)(seqno - next->tcphdr->seqno);
+                    pbuf_realloc(next->p, next->len);
+                  }
+                  /* check if the remote side overruns our receive window */
+                  if ((u32_t)tcplen + seqno > pcb->rcv_nxt + (u32_t)pcb->rcv_wnd) {
+                    LWIP_DEBUGF(TCP_INPUT_DEBUG, 
+                                ("tcp_receive: other end overran receive window"
+                                 "seqno %"U32_F" len %"U16_F" right edge %"U32_F"\n",
+                                 seqno, tcplen, pcb->rcv_nxt + pcb->rcv_wnd));
+                    if (TCPH_FLAGS(next->next->tcphdr) & TCP_FIN) {
+                      /* Must remove the FIN from the header as we're trimming 
+                       * that byte of sequence-space from the packet */
+                      TCPH_FLAGS_SET(next->next->tcphdr, TCPH_FLAGS(next->next->tcphdr) &~ TCP_FIN);
+                    }
+                    /* Adjust length of segment to fit in the window. */
+                    next->next->len = pcb->rcv_nxt + pcb->rcv_wnd - seqno;
+                    pbuf_realloc(next->next->p, next->next->len);
+                    tcplen = TCP_TCPLEN(next->next);
+                    LWIP_ASSERT("tcp_receive: segment not trimmed correctly to rcv_wnd\n",
+                                (seqno + tcplen) == (pcb->rcv_nxt + pcb->rcv_wnd));
+                  }
+                }
+                break;
+              }
+            }
+            prev = next;
+          }
+        }
+#endif /* TCP_QUEUE_OOSEQ */
+
+      }
+    } else {
+      /* The incoming segment is not withing the window. */
+      tcp_send_empty_ack(pcb);
+    }
+  } else {
+    /* Segments with length 0 is taken care of here. Segments that
+       fall out of the window are ACKed. */
+    /*if (TCP_SEQ_GT(pcb->rcv_nxt, seqno) ||
+      TCP_SEQ_GEQ(seqno, pcb->rcv_nxt + pcb->rcv_wnd)) {*/
+    if(!TCP_SEQ_BETWEEN(seqno, pcb->rcv_nxt, pcb->rcv_nxt + pcb->rcv_wnd-1)){
+      tcp_ack_now(pcb);
+    }
+  }
+}
+
+/**
+ * Parses the options contained in the incoming segment. 
+ *
+ * Called from tcp_listen_input() and tcp_process().
+ * Currently, only the MSS option is supported!
+ *
+ * @param pcb the tcp_pcb for which a segment arrived
+ */
+static void
+tcp_parseopt(struct tcp_pcb *pcb)
+{
+  u16_t c, max_c;
+  u16_t mss;
+  u8_t *opts, opt;
+#if LWIP_TCP_TIMESTAMPS
+  u32_t tsval;
+#endif
+
+  opts = (u8_t *)tcphdr + TCP_HLEN;
+
+  /* Parse the TCP MSS option, if present. */
+  if(TCPH_HDRLEN(tcphdr) > 0x5) {
+    max_c = (TCPH_HDRLEN(tcphdr) - 5) << 2;
+    for (c = 0; c < max_c; ) {
+      opt = opts[c];
+      switch (opt) {
+      case 0x00:
+        /* End of options. */
+        LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_parseopt: EOL\n"));
+        return;
+      case 0x01:
+        /* NOP option. */
+        ++c;
+        LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_parseopt: NOP\n"));
+        break;
+      case 0x02:
+        LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_parseopt: MSS\n"));
+        if (opts[c + 1] != 0x04 || c + 0x04 > max_c) {
+          /* Bad length */
+          LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_parseopt: bad length\n"));
+          return;
+        }
+        /* An MSS option with the right option length. */
+        mss = (opts[c + 2] << 8) | opts[c + 3];
+        /* Limit the mss to the configured TCP_MSS and prevent division by zero */
+        pcb->mss = ((mss > TCP_MSS) || (mss == 0)) ? TCP_MSS : mss;
+        /* Advance to next option */
+        c += 0x04;
+        break;
+#if LWIP_TCP_TIMESTAMPS
+      case 0x08:
+        LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_parseopt: TS\n"));
+        if (opts[c + 1] != 0x0A || c + 0x0A > max_c) {
+          /* Bad length */
+          LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_parseopt: bad length\n"));
+          return;
+        }
+        /* TCP timestamp option with valid length */
+        tsval = (opts[c+2]) | (opts[c+3] << 8) | 
+          (opts[c+4] << 16) | (opts[c+5] << 24);
+        if (flags & TCP_SYN) {
+          pcb->ts_recent = ntohl(tsval);
+          pcb->flags |= TF_TIMESTAMP;
+        } else if (TCP_SEQ_BETWEEN(pcb->ts_lastacksent, seqno, seqno+tcplen)) {
+          pcb->ts_recent = ntohl(tsval);
+        }
+        /* Advance to next option */
+        c += 0x0A;
+        break;
+#endif
+      default:
+        LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_parseopt: other\n"));
+        if (opts[c + 1] == 0) {
+          LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_parseopt: bad length\n"));
+          /* If the length field is zero, the options are malformed
+             and we don't process them further. */
+          return;
+        }
+        /* All other options have a length field, so that we easily
+           can skip past them. */
+        c += opts[c + 1];
+      }
+    }
+  }
+}
+
+#endif /* LWIP_TCP */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/core/tcp_out.c	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,1482 @@
+/**
+ * @file
+ * Transmission Control Protocol, outgoing traffic
+ *
+ * The output functions of TCP.
+ *
+ */
+
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ *
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+
+#include "lwip/opt.h"
+
+#if LWIP_TCP /* don't build if not configured for use in lwipopts.h */
+
+#include "lwip/tcp_impl.h"
+#include "lwip/def.h"
+#include "lwip/mem.h"
+#include "lwip/memp.h"
+#include "lwip/sys.h"
+#include "lwip/ip_addr.h"
+#include "lwip/netif.h"
+#include "lwip/inet_chksum.h"
+#include "lwip/stats.h"
+#include "lwip/snmp.h"
+
+#include <string.h>
+
+/* Define some copy-macros for checksum-on-copy so that the code looks
+   nicer by preventing too many ifdef's. */
+#if TCP_CHECKSUM_ON_COPY
+#define TCP_DATA_COPY(dst, src, len, seg) do { \
+  tcp_seg_add_chksum(LWIP_CHKSUM_COPY(dst, src, len), \
+                     len, &seg->chksum, &seg->chksum_swapped); \
+  seg->flags |= TF_SEG_DATA_CHECKSUMMED; } while(0)
+#define TCP_DATA_COPY2(dst, src, len, chksum, chksum_swapped)  \
+  tcp_seg_add_chksum(LWIP_CHKSUM_COPY(dst, src, len), len, chksum, chksum_swapped);
+#else /* TCP_CHECKSUM_ON_COPY*/
+#define TCP_DATA_COPY(dst, src, len, seg)                     MEMCPY(dst, src, len)
+#define TCP_DATA_COPY2(dst, src, len, chksum, chksum_swapped) MEMCPY(dst, src, len)
+#endif /* TCP_CHECKSUM_ON_COPY*/
+
+/** Define this to 1 for an extra check that the output checksum is valid
+ * (usefule when the checksum is generated by the application, not the stack) */
+#ifndef TCP_CHECKSUM_ON_COPY_SANITY_CHECK
+#define TCP_CHECKSUM_ON_COPY_SANITY_CHECK   0
+#endif
+
+/* Forward declarations.*/
+static void tcp_output_segment(struct tcp_seg *seg, struct tcp_pcb *pcb);
+
+/** Allocate a pbuf and create a tcphdr at p->payload, used for output
+ * functions other than the default tcp_output -> tcp_output_segment
+ * (e.g. tcp_send_empty_ack, etc.)
+ *
+ * @param pcb tcp pcb for which to send a packet (used to initialize tcp_hdr)
+ * @param optlen length of header-options
+ * @param datalen length of tcp data to reserve in pbuf
+ * @param seqno_be seqno in network byte order (big-endian)
+ * @return pbuf with p->payload being the tcp_hdr
+ */
+static struct pbuf *
+tcp_output_alloc_header(struct tcp_pcb *pcb, u16_t optlen, u16_t datalen,
+                      u32_t seqno_be /* already in network byte order */)
+{
+  struct tcp_hdr *tcphdr;
+  struct pbuf *p = pbuf_alloc(PBUF_IP, TCP_HLEN + optlen + datalen, PBUF_RAM);
+  if (p != NULL) {
+    LWIP_ASSERT("check that first pbuf can hold struct tcp_hdr",
+                 (p->len >= TCP_HLEN + optlen));
+    tcphdr = (struct tcp_hdr *)p->payload;
+    tcphdr->src = htons(pcb->local_port);
+    tcphdr->dest = htons(pcb->remote_port);
+    tcphdr->seqno = seqno_be;
+    tcphdr->ackno = htonl(pcb->rcv_nxt);
+    TCPH_HDRLEN_FLAGS_SET(tcphdr, (5 + optlen / 4), TCP_ACK);
+    tcphdr->wnd = htons(pcb->rcv_ann_wnd);
+    tcphdr->chksum = 0;
+    tcphdr->urgp = 0;
+
+    /* If we're sending a packet, update the announced right window edge */
+    pcb->rcv_ann_right_edge = pcb->rcv_nxt + pcb->rcv_ann_wnd;
+  }
+  return p;
+}
+
+/**
+ * Called by tcp_close() to send a segment including FIN flag but not data.
+ *
+ * @param pcb the tcp_pcb over which to send a segment
+ * @return ERR_OK if sent, another err_t otherwise
+ */
+err_t
+tcp_send_fin(struct tcp_pcb *pcb)
+{
+  /* first, try to add the fin to the last unsent segment */
+  if (pcb->unsent != NULL) {
+    struct tcp_seg *last_unsent;
+    for (last_unsent = pcb->unsent; last_unsent->next != NULL;
+         last_unsent = last_unsent->next);
+
+    if ((TCPH_FLAGS(last_unsent->tcphdr) & (TCP_SYN | TCP_FIN | TCP_RST)) == 0) {
+      /* no SYN/FIN/RST flag in the header, we can add the FIN flag */
+      TCPH_SET_FLAG(last_unsent->tcphdr, TCP_FIN);
+      return ERR_OK;
+    }
+  }
+  /* no data, no length, flags, copy=1, no optdata */
+  return tcp_enqueue_flags(pcb, TCP_FIN);
+}
+
+/**
+ * Create a TCP segment with prefilled header.
+ *
+ * Called by tcp_write and tcp_enqueue_flags.
+ *
+ * @param pcb Protocol control block for the TCP connection.
+ * @param p pbuf that is used to hold the TCP header.
+ * @param flags TCP flags for header.
+ * @param seqno TCP sequence number of this packet
+ * @param optflags options to include in TCP header
+ * @return a new tcp_seg pointing to p, or NULL.
+ * The TCP header is filled in except ackno and wnd.
+ * p is freed on failure.
+ */
+static struct tcp_seg *
+tcp_create_segment(struct tcp_pcb *pcb, struct pbuf *p, u8_t flags, u32_t seqno, u8_t optflags)
+{
+  struct tcp_seg *seg;
+  u8_t optlen = LWIP_TCP_OPT_LENGTH(optflags);
+
+  if ((seg = (struct tcp_seg *)memp_malloc(MEMP_TCP_SEG)) == NULL) {
+    LWIP_DEBUGF(TCP_OUTPUT_DEBUG | 2, ("tcp_create_segment: no memory.\n"));
+    pbuf_free(p);
+    return NULL;
+  }
+  seg->flags = optflags;
+  seg->next = NULL;
+  seg->p = p;
+  seg->dataptr = p->payload;
+  seg->len = p->tot_len - optlen;
+#if TCP_OVERSIZE_DBGCHECK
+  seg->oversize_left = 0;
+#endif /* TCP_OVERSIZE_DBGCHECK */
+#if TCP_CHECKSUM_ON_COPY
+  seg->chksum = 0;
+  seg->chksum_swapped = 0;
+  /* check optflags */
+  LWIP_ASSERT("invalid optflags passed: TF_SEG_DATA_CHECKSUMMED",
+              (optflags & TF_SEG_DATA_CHECKSUMMED) == 0);
+#endif /* TCP_CHECKSUM_ON_COPY */
+
+  /* build TCP header */
+  if (pbuf_header(p, TCP_HLEN)) {
+    LWIP_DEBUGF(TCP_OUTPUT_DEBUG | 2, ("tcp_create_segment: no room for TCP header in pbuf.\n"));
+    TCP_STATS_INC(tcp.err);
+    tcp_seg_free(seg);
+    return NULL;
+  }
+  seg->tcphdr = (struct tcp_hdr *)seg->p->payload;
+  seg->tcphdr->src = htons(pcb->local_port);
+  seg->tcphdr->dest = htons(pcb->remote_port);
+  seg->tcphdr->seqno = htonl(seqno);
+  /* ackno is set in tcp_output */
+  TCPH_HDRLEN_FLAGS_SET(seg->tcphdr, (5 + optlen / 4), flags);
+  /* wnd and chksum are set in tcp_output */
+  seg->tcphdr->urgp = 0;
+  return seg;
+} 
+
+/**
+ * Allocate a PBUF_RAM pbuf, perhaps with extra space at the end.
+ *
+ * This function is like pbuf_alloc(layer, length, PBUF_RAM) except
+ * there may be extra bytes available at the end.
+ *
+ * @param layer flag to define header size.
+ * @param length size of the pbuf's payload.
+ * @param max_length maximum usable size of payload+oversize.
+ * @param oversize pointer to a u16_t that will receive the number of usable tail bytes.
+ * @param pcb The TCP connection that willo enqueue the pbuf.
+ * @param apiflags API flags given to tcp_write.
+ * @param first_seg true when this pbuf will be used in the first enqueued segment.
+ * @param 
+ */
+#if TCP_OVERSIZE
+static struct pbuf *
+tcp_pbuf_prealloc(pbuf_layer layer, u16_t length, u16_t max_length,
+                  u16_t *oversize, struct tcp_pcb *pcb, u8_t apiflags,
+                  u8_t first_seg)
+{
+  struct pbuf *p;
+  u16_t alloc = length;
+
+#if LWIP_NETIF_TX_SINGLE_PBUF
+  LWIP_UNUSED_ARG(max_length);
+  LWIP_UNUSED_ARG(pcb);
+  LWIP_UNUSED_ARG(apiflags);
+  LWIP_UNUSED_ARG(first_seg);
+  /* always create MSS-sized pbufs */
+  alloc = TCP_MSS;
+#else /* LWIP_NETIF_TX_SINGLE_PBUF */
+  if (length < max_length) {
+    /* Should we allocate an oversized pbuf, or just the minimum
+     * length required? If tcp_write is going to be called again
+     * before this segment is transmitted, we want the oversized
+     * buffer. If the segment will be transmitted immediately, we can
+     * save memory by allocating only length. We use a simple
+     * heuristic based on the following information:
+     *
+     * Did the user set TCP_WRITE_FLAG_MORE?
+     *
+     * Will the Nagle algorithm defer transmission of this segment?
+     */
+    if ((apiflags & TCP_WRITE_FLAG_MORE) ||
+        (!(pcb->flags & TF_NODELAY) &&
+         (!first_seg ||
+          pcb->unsent != NULL ||
+          pcb->unacked != NULL))) {
+      alloc = LWIP_MIN(max_length, LWIP_MEM_ALIGN_SIZE(length + TCP_OVERSIZE));
+    }
+  }
+#endif /* LWIP_NETIF_TX_SINGLE_PBUF */
+  p = pbuf_alloc(layer, alloc, PBUF_RAM);
+  if (p == NULL) {
+    return NULL;
+  }
+  LWIP_ASSERT("need unchained pbuf", p->next == NULL);
+  *oversize = p->len - length;
+  /* trim p->len to the currently used size */
+  p->len = p->tot_len = length;
+  return p;
+}
+#else /* TCP_OVERSIZE */
+#define tcp_pbuf_prealloc(layer, length, mx, os, pcb, api, fst) pbuf_alloc((layer), (length), PBUF_RAM)
+#endif /* TCP_OVERSIZE */
+
+#if TCP_CHECKSUM_ON_COPY
+/** Add a checksum of newly added data to the segment */
+static void
+tcp_seg_add_chksum(u16_t chksum, u16_t len, u16_t *seg_chksum,
+                   u8_t *seg_chksum_swapped)
+{
+  u32_t helper;
+  /* add chksum to old chksum and fold to u16_t */
+  helper = chksum + *seg_chksum;
+  chksum = FOLD_U32T(helper);
+  if ((len & 1) != 0) {
+    *seg_chksum_swapped = 1 - *seg_chksum_swapped;
+    chksum = SWAP_BYTES_IN_WORD(chksum);
+  }
+  *seg_chksum = chksum;
+}
+#endif /* TCP_CHECKSUM_ON_COPY */
+
+/** Checks if tcp_write is allowed or not (checks state, snd_buf and snd_queuelen).
+ *
+ * @param pcb the tcp pcb to check for
+ * @param len length of data to send (checked agains snd_buf)
+ * @return ERR_OK if tcp_write is allowed to proceed, another err_t otherwise
+ */
+static err_t
+tcp_write_checks(struct tcp_pcb *pcb, u16_t len)
+{
+  /* connection is in invalid state for data transmission? */
+  if ((pcb->state != ESTABLISHED) &&
+      (pcb->state != CLOSE_WAIT) &&
+      (pcb->state != SYN_SENT) &&
+      (pcb->state != SYN_RCVD)) {
+    LWIP_DEBUGF(TCP_OUTPUT_DEBUG | LWIP_DBG_STATE | LWIP_DBG_LEVEL_SEVERE, ("tcp_write() called in invalid state\n"));
+    return ERR_CONN;
+  } else if (len == 0) {
+    return ERR_OK;
+  }
+
+  /* fail on too much data */
+  if (len > pcb->snd_buf) {
+    LWIP_DEBUGF(TCP_OUTPUT_DEBUG | 3, ("tcp_write: too much data (len=%"U16_F" > snd_buf=%"U16_F")\n",
+      len, pcb->snd_buf));
+    pcb->flags |= TF_NAGLEMEMERR;
+    return ERR_MEM;
+  }
+
+  LWIP_DEBUGF(TCP_QLEN_DEBUG, ("tcp_write: queuelen: %"U16_F"\n", (u16_t)pcb->snd_queuelen));
+
+  /* If total number of pbufs on the unsent/unacked queues exceeds the
+   * configured maximum, return an error */
+  /* check for configured max queuelen and possible overflow */
+  if ((pcb->snd_queuelen >= TCP_SND_QUEUELEN) || (pcb->snd_queuelen > TCP_SNDQUEUELEN_OVERFLOW)) {
+    LWIP_DEBUGF(TCP_OUTPUT_DEBUG | 3, ("tcp_write: too long queue %"U16_F" (max %"U16_F")\n",
+      pcb->snd_queuelen, TCP_SND_QUEUELEN));
+    TCP_STATS_INC(tcp.memerr);
+    pcb->flags |= TF_NAGLEMEMERR;
+    return ERR_MEM;
+  }
+  if (pcb->snd_queuelen != 0) {
+    LWIP_ASSERT("tcp_write: pbufs on queue => at least one queue non-empty",
+      pcb->unacked != NULL || pcb->unsent != NULL);
+  } else {
+    LWIP_ASSERT("tcp_write: no pbufs on queue => both queues empty",
+      pcb->unacked == NULL && pcb->unsent == NULL);
+  }
+  return ERR_OK;
+}
+
+/**
+ * Write data for sending (but does not send it immediately).
+ *
+ * It waits in the expectation of more data being sent soon (as
+ * it can send them more efficiently by combining them together).
+ * To prompt the system to send data now, call tcp_output() after
+ * calling tcp_write().
+ *
+ * @param pcb Protocol control block for the TCP connection to enqueue data for.
+ * @param arg Pointer to the data to be enqueued for sending.
+ * @param len Data length in bytes
+ * @param apiflags combination of following flags :
+ * - TCP_WRITE_FLAG_COPY (0x01) data will be copied into memory belonging to the stack
+ * - TCP_WRITE_FLAG_MORE (0x02) for TCP connection, PSH flag will be set on last segment sent,
+ * @return ERR_OK if enqueued, another err_t on error
+ */
+err_t
+tcp_write(struct tcp_pcb *pcb, const void *arg, u16_t len, u8_t apiflags)
+{
+  struct pbuf *concat_p = NULL;
+  struct tcp_seg *last_unsent = NULL, *seg = NULL, *prev_seg = NULL, *queue = NULL;
+  u16_t pos = 0; /* position in 'arg' data */
+  u16_t queuelen;
+  u8_t optlen = 0;
+  u8_t optflags = 0;
+#if TCP_OVERSIZE
+  u16_t oversize = 0;
+  u16_t oversize_used = 0;
+#endif /* TCP_OVERSIZE */
+#if TCP_CHECKSUM_ON_COPY
+  u16_t concat_chksum = 0;
+  u8_t concat_chksum_swapped = 0;
+  u16_t concat_chksummed = 0;
+#endif /* TCP_CHECKSUM_ON_COPY */
+  err_t err;
+
+#if LWIP_NETIF_TX_SINGLE_PBUF
+  /* Always copy to try to create single pbufs for TX */
+  apiflags |= TCP_WRITE_FLAG_COPY;
+#endif /* LWIP_NETIF_TX_SINGLE_PBUF */
+
+  LWIP_DEBUGF(TCP_OUTPUT_DEBUG, ("tcp_write(pcb=%p, data=%p, len=%"U16_F", apiflags=%"U16_F")\n",
+    (void *)pcb, arg, len, (u16_t)apiflags));
+  LWIP_ERROR("tcp_write: arg == NULL (programmer violates API)", 
+             arg != NULL, return ERR_ARG;);
+
+  err = tcp_write_checks(pcb, len);
+  if (err != ERR_OK) {
+    return err;
+  }
+  queuelen = pcb->snd_queuelen;
+
+#if LWIP_TCP_TIMESTAMPS
+  if ((pcb->flags & TF_TIMESTAMP)) {
+    optflags = TF_SEG_OPTS_TS;
+    optlen = LWIP_TCP_OPT_LENGTH(TF_SEG_OPTS_TS);
+  }
+#endif /* LWIP_TCP_TIMESTAMPS */
+
+
+  /*
+   * TCP segmentation is done in three phases with increasing complexity:
+   *
+   * 1. Copy data directly into an oversized pbuf.
+   * 2. Chain a new pbuf to the end of pcb->unsent.
+   * 3. Create new segments.
+   *
+   * We may run out of memory at any point. In that case we must
+   * return ERR_MEM and not change anything in pcb. Therefore, all
+   * changes are recorded in local variables and committed at the end
+   * of the function. Some pcb fields are maintained in local copies:
+   *
+   * queuelen = pcb->snd_queuelen
+   * oversize = pcb->unsent_oversize
+   *
+   * These variables are set consistently by the phases:
+   *
+   * seg points to the last segment tampered with.
+   *
+   * pos records progress as data is segmented.
+   */
+
+  /* Find the tail of the unsent queue. */
+  if (pcb->unsent != NULL) {
+    u16_t space;
+    u16_t unsent_optlen;
+
+    /* @todo: this could be sped up by keeping last_unsent in the pcb */
+    for (last_unsent = pcb->unsent; last_unsent->next != NULL;
+         last_unsent = last_unsent->next);
+
+    /* Usable space at the end of the last unsent segment */
+    unsent_optlen = LWIP_TCP_OPT_LENGTH(last_unsent->flags);
+    space = pcb->mss - (last_unsent->len + unsent_optlen);
+
+    /*
+     * Phase 1: Copy data directly into an oversized pbuf.
+     *
+     * The number of bytes copied is recorded in the oversize_used
+     * variable. The actual copying is done at the bottom of the
+     * function.
+     */
+#if TCP_OVERSIZE
+#if TCP_OVERSIZE_DBGCHECK
+    /* check that pcb->unsent_oversize matches last_unsent->unsent_oversize */
+    LWIP_ASSERT("unsent_oversize mismatch (pcb vs. last_unsent)",
+                pcb->unsent_oversize == last_unsent->oversize_left);
+#endif /* TCP_OVERSIZE_DBGCHECK */
+    oversize = pcb->unsent_oversize;
+    if (oversize > 0) {
+      LWIP_ASSERT("inconsistent oversize vs. space", oversize_used <= space);
+      seg = last_unsent;
+      oversize_used = oversize < len ? oversize : len;
+      pos += oversize_used;
+      oversize -= oversize_used;
+      space -= oversize_used;
+    }
+    /* now we are either finished or oversize is zero */
+    LWIP_ASSERT("inconsistend oversize vs. len", (oversize == 0) || (pos == len));
+#endif /* TCP_OVERSIZE */
+
+    /*
+     * Phase 2: Chain a new pbuf to the end of pcb->unsent.
+     *
+     * We don't extend segments containing SYN/FIN flags or options
+     * (len==0). The new pbuf is kept in concat_p and pbuf_cat'ed at
+     * the end.
+     */
+    if ((pos < len) && (space > 0) && (last_unsent->len > 0)) {
+      u16_t seglen = space < len - pos ? space : len - pos;
+      seg = last_unsent;
+
+      /* Create a pbuf with a copy or reference to seglen bytes. We
+       * can use PBUF_RAW here since the data appears in the middle of
+       * a segment. A header will never be prepended. */
+      if (apiflags & TCP_WRITE_FLAG_COPY) {
+        /* Data is copied */
+        if ((concat_p = tcp_pbuf_prealloc(PBUF_RAW, seglen, space, &oversize, pcb, apiflags, 1)) == NULL) {
+          LWIP_DEBUGF(TCP_OUTPUT_DEBUG | 2,
+                      ("tcp_write : could not allocate memory for pbuf copy size %"U16_F"\n",
+                       seglen));
+          goto memerr;
+        }
+#if TCP_OVERSIZE_DBGCHECK
+        last_unsent->oversize_left = oversize;
+#endif /* TCP_OVERSIZE_DBGCHECK */
+        TCP_DATA_COPY2(concat_p->payload, (u8_t*)arg + pos, seglen, &concat_chksum, &concat_chksum_swapped);
+#if TCP_CHECKSUM_ON_COPY
+        concat_chksummed += seglen;
+#endif /* TCP_CHECKSUM_ON_COPY */
+      } else {
+        /* Data is not copied */
+        if ((concat_p = pbuf_alloc(PBUF_RAW, seglen, PBUF_ROM)) == NULL) {
+          LWIP_DEBUGF(TCP_OUTPUT_DEBUG | 2,
+                      ("tcp_write: could not allocate memory for zero-copy pbuf\n"));
+          goto memerr;
+        }
+#if TCP_CHECKSUM_ON_COPY
+        /* calculate the checksum of nocopy-data */
+        tcp_seg_add_chksum(~inet_chksum((u8_t*)arg + pos, seglen), seglen,
+          &concat_chksum, &concat_chksum_swapped);
+        concat_chksummed += seglen;
+#endif /* TCP_CHECKSUM_ON_COPY */
+        /* reference the non-volatile payload data */
+        concat_p->payload = (u8_t*)arg + pos;
+      }
+
+      pos += seglen;
+      queuelen += pbuf_clen(concat_p);
+    }
+  } else {
+#if TCP_OVERSIZE
+    LWIP_ASSERT("unsent_oversize mismatch (pcb->unsent is NULL)",
+                pcb->unsent_oversize == 0);
+#endif /* TCP_OVERSIZE */
+  }
+
+  /*
+   * Phase 3: Create new segments.
+   *
+   * The new segments are chained together in the local 'queue'
+   * variable, ready to be appended to pcb->unsent.
+   */
+  while (pos < len) {
+    struct pbuf *p;
+    u16_t left = len - pos;
+    u16_t max_len = pcb->mss - optlen;
+    u16_t seglen = left > max_len ? max_len : left;
+#if TCP_CHECKSUM_ON_COPY
+    u16_t chksum = 0;
+    u8_t chksum_swapped = 0;
+#endif /* TCP_CHECKSUM_ON_COPY */
+
+    if (apiflags & TCP_WRITE_FLAG_COPY) {
+      /* If copy is set, memory should be allocated and data copied
+       * into pbuf */
+      if ((p = tcp_pbuf_prealloc(PBUF_TRANSPORT, seglen + optlen, pcb->mss, &oversize, pcb, apiflags, queue == NULL)) == NULL) {
+        LWIP_DEBUGF(TCP_OUTPUT_DEBUG | 2, ("tcp_write : could not allocate memory for pbuf copy size %"U16_F"\n", seglen));
+        goto memerr;
+      }
+      LWIP_ASSERT("tcp_write: check that first pbuf can hold the complete seglen",
+                  (p->len >= seglen));
+      TCP_DATA_COPY2((char *)p->payload + optlen, (u8_t*)arg + pos, seglen, &chksum, &chksum_swapped);
+    } else {
+      /* Copy is not set: First allocate a pbuf for holding the data.
+       * Since the referenced data is available at least until it is
+       * sent out on the link (as it has to be ACKed by the remote
+       * party) we can safely use PBUF_ROM instead of PBUF_REF here.
+       */
+      struct pbuf *p2;
+#if TCP_OVERSIZE
+      LWIP_ASSERT("oversize == 0", oversize == 0);
+#endif /* TCP_OVERSIZE */
+      if ((p2 = pbuf_alloc(PBUF_TRANSPORT, seglen, PBUF_ROM)) == NULL) {
+        LWIP_DEBUGF(TCP_OUTPUT_DEBUG | 2, ("tcp_write: could not allocate memory for zero-copy pbuf\n"));
+        goto memerr;
+      }
+#if TCP_CHECKSUM_ON_COPY
+      /* calculate the checksum of nocopy-data */
+      chksum = ~inet_chksum((u8_t*)arg + pos, seglen);
+#endif /* TCP_CHECKSUM_ON_COPY */
+      /* reference the non-volatile payload data */
+      p2->payload = (u8_t*)arg + pos;
+
+      /* Second, allocate a pbuf for the headers. */
+      if ((p = pbuf_alloc(PBUF_TRANSPORT, optlen, PBUF_RAM)) == NULL) {
+        /* If allocation fails, we have to deallocate the data pbuf as
+         * well. */
+        pbuf_free(p2);
+        LWIP_DEBUGF(TCP_OUTPUT_DEBUG | 2, ("tcp_write: could not allocate memory for header pbuf\n"));
+        goto memerr;
+      }
+      /* Concatenate the headers and data pbufs together. */
+      pbuf_cat(p/*header*/, p2/*data*/);
+    }
+
+    queuelen += pbuf_clen(p);
+
+    /* Now that there are more segments queued, we check again if the
+     * length of the queue exceeds the configured maximum or
+     * overflows. */
+    if ((queuelen > TCP_SND_QUEUELEN) || (queuelen > TCP_SNDQUEUELEN_OVERFLOW)) {
+      LWIP_DEBUGF(TCP_OUTPUT_DEBUG | 2, ("tcp_write: queue too long %"U16_F" (%"U16_F")\n", queuelen, TCP_SND_QUEUELEN));
+      pbuf_free(p);
+      goto memerr;
+    }
+
+    if ((seg = tcp_create_segment(pcb, p, 0, pcb->snd_lbb + pos, optflags)) == NULL) {
+      goto memerr;
+    }
+#if TCP_OVERSIZE_DBGCHECK
+    seg->oversize_left = oversize;
+#endif /* TCP_OVERSIZE_DBGCHECK */
+#if TCP_CHECKSUM_ON_COPY
+    seg->chksum = chksum;
+    seg->chksum_swapped = chksum_swapped;
+    seg->flags |= TF_SEG_DATA_CHECKSUMMED;
+#endif /* TCP_CHECKSUM_ON_COPY */
+    /* Fix dataptr for the nocopy case */
+    if ((apiflags & TCP_WRITE_FLAG_COPY) == 0) {
+      seg->dataptr = (u8_t*)arg + pos;
+    }
+
+    /* first segment of to-be-queued data? */
+    if (queue == NULL) {
+      queue = seg;
+    } else {
+      /* Attach the segment to the end of the queued segments */
+      LWIP_ASSERT("prev_seg != NULL", prev_seg != NULL);
+      prev_seg->next = seg;
+    }
+    /* remember last segment of to-be-queued data for next iteration */
+    prev_seg = seg;
+
+    LWIP_DEBUGF(TCP_OUTPUT_DEBUG | LWIP_DBG_TRACE, ("tcp_write: queueing %"U32_F":%"U32_F"\n",
+      ntohl(seg->tcphdr->seqno),
+      ntohl(seg->tcphdr->seqno) + TCP_TCPLEN(seg)));
+
+    pos += seglen;
+  }
+
+  /*
+   * All three segmentation phases were successful. We can commit the
+   * transaction.
+   */
+
+  /*
+   * Phase 1: If data has been added to the preallocated tail of
+   * last_unsent, we update the length fields of the pbuf chain.
+   */
+#if TCP_OVERSIZE
+  if (oversize_used > 0) {
+    struct pbuf *p;
+    /* Bump tot_len of whole chain, len of tail */
+    for (p = last_unsent->p; p; p = p->next) {
+      p->tot_len += oversize_used;
+      if (p->next == NULL) {
+        TCP_DATA_COPY((char *)p->payload + p->len, arg, oversize_used, last_unsent);
+        p->len += oversize_used;
+      }
+    }
+    last_unsent->len += oversize_used;
+#if TCP_OVERSIZE_DBGCHECK
+    last_unsent->oversize_left -= oversize_used;
+#endif /* TCP_OVERSIZE_DBGCHECK */
+  }
+  pcb->unsent_oversize = oversize;
+#endif /* TCP_OVERSIZE */
+
+  /*
+   * Phase 2: concat_p can be concatenated onto last_unsent->p
+   */
+  if (concat_p != NULL) {
+    LWIP_ASSERT("tcp_write: cannot concatenate when pcb->unsent is empty",
+      (last_unsent != NULL));
+    pbuf_cat(last_unsent->p, concat_p);
+    last_unsent->len += concat_p->tot_len;
+#if TCP_CHECKSUM_ON_COPY
+    if (concat_chksummed) {
+      tcp_seg_add_chksum(concat_chksum, concat_chksummed, &last_unsent->chksum,
+        &last_unsent->chksum_swapped);
+      last_unsent->flags |= TF_SEG_DATA_CHECKSUMMED;
+    }
+#endif /* TCP_CHECKSUM_ON_COPY */
+  }
+
+  /*
+   * Phase 3: Append queue to pcb->unsent. Queue may be NULL, but that
+   * is harmless
+   */
+  if (last_unsent == NULL) {
+    pcb->unsent = queue;
+  } else {
+    last_unsent->next = queue;
+  }
+
+  /*
+   * Finally update the pcb state.
+   */
+  pcb->snd_lbb += len;
+  pcb->snd_buf -= len;
+  pcb->snd_queuelen = queuelen;
+
+  LWIP_DEBUGF(TCP_QLEN_DEBUG, ("tcp_write: %"S16_F" (after enqueued)\n",
+    pcb->snd_queuelen));
+  if (pcb->snd_queuelen != 0) {
+    LWIP_ASSERT("tcp_write: valid queue length",
+                pcb->unacked != NULL || pcb->unsent != NULL);
+  }
+
+  /* Set the PSH flag in the last segment that we enqueued. */
+  if (seg != NULL && seg->tcphdr != NULL && ((apiflags & TCP_WRITE_FLAG_MORE)==0)) {
+    TCPH_SET_FLAG(seg->tcphdr, TCP_PSH);
+  }
+
+  return ERR_OK;
+memerr:
+  pcb->flags |= TF_NAGLEMEMERR;
+  TCP_STATS_INC(tcp.memerr);
+
+  if (concat_p != NULL) {
+    pbuf_free(concat_p);
+  }
+  if (queue != NULL) {
+    tcp_segs_free(queue);
+  }
+  if (pcb->snd_queuelen != 0) {
+    LWIP_ASSERT("tcp_write: valid queue length", pcb->unacked != NULL ||
+      pcb->unsent != NULL);
+  }
+  LWIP_DEBUGF(TCP_QLEN_DEBUG | LWIP_DBG_STATE, ("tcp_write: %"S16_F" (with mem err)\n", pcb->snd_queuelen));
+  return ERR_MEM;
+}
+
+/**
+ * Enqueue TCP options for transmission.
+ *
+ * Called by tcp_connect(), tcp_listen_input(), and tcp_send_ctrl().
+ *
+ * @param pcb Protocol control block for the TCP connection.
+ * @param flags TCP header flags to set in the outgoing segment.
+ * @param optdata pointer to TCP options, or NULL.
+ * @param optlen length of TCP options in bytes.
+ */
+err_t
+tcp_enqueue_flags(struct tcp_pcb *pcb, u8_t flags)
+{
+  struct pbuf *p;
+  struct tcp_seg *seg;
+  u8_t optflags = 0;
+  u8_t optlen = 0;
+
+  LWIP_DEBUGF(TCP_QLEN_DEBUG, ("tcp_enqueue_flags: queuelen: %"U16_F"\n", (u16_t)pcb->snd_queuelen));
+
+  LWIP_ASSERT("tcp_enqueue_flags: need either TCP_SYN or TCP_FIN in flags (programmer violates API)",
+              (flags & (TCP_SYN | TCP_FIN)) != 0);
+
+  /* check for configured max queuelen and possible overflow */
+  if ((pcb->snd_queuelen >= TCP_SND_QUEUELEN) || (pcb->snd_queuelen > TCP_SNDQUEUELEN_OVERFLOW)) {
+    LWIP_DEBUGF(TCP_OUTPUT_DEBUG | 3, ("tcp_enqueue_flags: too long queue %"U16_F" (max %"U16_F")\n",
+                                       pcb->snd_queuelen, TCP_SND_QUEUELEN));
+    TCP_STATS_INC(tcp.memerr);
+    pcb->flags |= TF_NAGLEMEMERR;
+    return ERR_MEM;
+  }
+
+  if (flags & TCP_SYN) {
+    optflags = TF_SEG_OPTS_MSS;
+  }
+#if LWIP_TCP_TIMESTAMPS
+  if ((pcb->flags & TF_TIMESTAMP)) {
+    optflags |= TF_SEG_OPTS_TS;
+  }
+#endif /* LWIP_TCP_TIMESTAMPS */
+  optlen = LWIP_TCP_OPT_LENGTH(optflags);
+
+  /* tcp_enqueue_flags is always called with either SYN or FIN in flags.
+   * We need one available snd_buf byte to do that.
+   * This means we can't send FIN while snd_buf==0. A better fix would be to
+   * not include SYN and FIN sequence numbers in the snd_buf count. */
+  if (pcb->snd_buf == 0) {
+    LWIP_DEBUGF(TCP_OUTPUT_DEBUG | 3, ("tcp_enqueue_flags: no send buffer available\n"));
+    TCP_STATS_INC(tcp.memerr);
+    return ERR_MEM;
+  }
+
+  /* Allocate pbuf with room for TCP header + options */
+  if ((p = pbuf_alloc(PBUF_TRANSPORT, optlen, PBUF_RAM)) == NULL) {
+    pcb->flags |= TF_NAGLEMEMERR;
+    TCP_STATS_INC(tcp.memerr);
+    return ERR_MEM;
+  }
+  LWIP_ASSERT("tcp_enqueue_flags: check that first pbuf can hold optlen",
+              (p->len >= optlen));
+
+  /* Allocate memory for tcp_seg, and fill in fields. */
+  if ((seg = tcp_create_segment(pcb, p, flags, pcb->snd_lbb, optflags)) == NULL) {
+    pcb->flags |= TF_NAGLEMEMERR;
+    TCP_STATS_INC(tcp.memerr);
+    return ERR_MEM;
+  }
+  LWIP_ASSERT("tcp_enqueue_flags: invalid segment length", seg->len == 0);
+
+  LWIP_DEBUGF(TCP_OUTPUT_DEBUG | LWIP_DBG_TRACE,
+              ("tcp_enqueue_flags: queueing %"U32_F":%"U32_F" (0x%"X16_F")\n",
+               ntohl(seg->tcphdr->seqno),
+               ntohl(seg->tcphdr->seqno) + TCP_TCPLEN(seg),
+               (u16_t)flags));
+
+  /* Now append seg to pcb->unsent queue */
+  if (pcb->unsent == NULL) {
+    pcb->unsent = seg;
+  } else {
+    struct tcp_seg *useg;
+    for (useg = pcb->unsent; useg->next != NULL; useg = useg->next);
+    useg->next = seg;
+  }
+#if TCP_OVERSIZE
+  /* The new unsent tail has no space */
+  pcb->unsent_oversize = 0;
+#endif /* TCP_OVERSIZE */
+
+  /* SYN and FIN bump the sequence number */
+  if ((flags & TCP_SYN) || (flags & TCP_FIN)) {
+    pcb->snd_lbb++;
+    /* optlen does not influence snd_buf */
+    pcb->snd_buf--;
+  }
+  if (flags & TCP_FIN) {
+    pcb->flags |= TF_FIN;
+  }
+
+  /* update number of segments on the queues */
+  pcb->snd_queuelen += pbuf_clen(seg->p);
+  LWIP_DEBUGF(TCP_QLEN_DEBUG, ("tcp_enqueue_flags: %"S16_F" (after enqueued)\n", pcb->snd_queuelen));
+  if (pcb->snd_queuelen != 0) {
+    LWIP_ASSERT("tcp_enqueue_flags: invalid queue length",
+      pcb->unacked != NULL || pcb->unsent != NULL);
+  }
+
+  return ERR_OK;
+}
+ 
+
+#if LWIP_TCP_TIMESTAMPS
+/* Build a timestamp option (12 bytes long) at the specified options pointer)
+ *
+ * @param pcb tcp_pcb
+ * @param opts option pointer where to store the timestamp option
+ */
+static void
+tcp_build_timestamp_option(struct tcp_pcb *pcb, u32_t *opts)
+{
+  /* Pad with two NOP options to make everything nicely aligned */
+  opts[0] = PP_HTONL(0x0101080A);
+  opts[1] = htonl(sys_now());
+  opts[2] = htonl(pcb->ts_recent);
+}
+#endif
+
+/** Send an ACK without data.
+ *
+ * @param pcb Protocol control block for the TCP connection to send the ACK
+ */
+err_t
+tcp_send_empty_ack(struct tcp_pcb *pcb)
+{
+  struct pbuf *p;
+  struct tcp_hdr *tcphdr;
+  u8_t optlen = 0;
+
+#if LWIP_TCP_TIMESTAMPS
+  if (pcb->flags & TF_TIMESTAMP) {
+    optlen = LWIP_TCP_OPT_LENGTH(TF_SEG_OPTS_TS);
+  }
+#endif
+
+  p = tcp_output_alloc_header(pcb, optlen, 0, htonl(pcb->snd_nxt));
+  if (p == NULL) {
+    LWIP_DEBUGF(TCP_OUTPUT_DEBUG, ("tcp_output: (ACK) could not allocate pbuf\n"));
+    return ERR_BUF;
+  }
+  tcphdr = (struct tcp_hdr *)p->payload;
+  LWIP_DEBUGF(TCP_OUTPUT_DEBUG, 
+              ("tcp_output: sending ACK for %"U32_F"\n", pcb->rcv_nxt));
+  /* remove ACK flags from the PCB, as we send an empty ACK now */
+  pcb->flags &= ~(TF_ACK_DELAY | TF_ACK_NOW);
+
+  /* NB. MSS option is only sent on SYNs, so ignore it here */
+#if LWIP_TCP_TIMESTAMPS
+  pcb->ts_lastacksent = pcb->rcv_nxt;
+
+  if (pcb->flags & TF_TIMESTAMP) {
+    tcp_build_timestamp_option(pcb, (u32_t *)(tcphdr + 1));
+  }
+#endif 
+
+#if CHECKSUM_GEN_TCP
+  tcphdr->chksum = inet_chksum_pseudo(p, &(pcb->local_ip), &(pcb->remote_ip),
+        IP_PROTO_TCP, p->tot_len);
+#endif
+#if LWIP_NETIF_HWADDRHINT
+  ip_output_hinted(p, &(pcb->local_ip), &(pcb->remote_ip), pcb->ttl, pcb->tos,
+      IP_PROTO_TCP, &(pcb->addr_hint));
+#else /* LWIP_NETIF_HWADDRHINT*/
+  ip_output(p, &(pcb->local_ip), &(pcb->remote_ip), pcb->ttl, pcb->tos,
+      IP_PROTO_TCP);
+#endif /* LWIP_NETIF_HWADDRHINT*/
+  pbuf_free(p);
+
+  return ERR_OK;
+}
+
+/**
+ * Find out what we can send and send it
+ *
+ * @param pcb Protocol control block for the TCP connection to send data
+ * @return ERR_OK if data has been sent or nothing to send
+ *         another err_t on error
+ */
+err_t
+tcp_output(struct tcp_pcb *pcb)
+{
+  struct tcp_seg *seg, *useg;
+  u32_t wnd, snd_nxt;
+#if TCP_CWND_DEBUG
+  s16_t i = 0;
+#endif /* TCP_CWND_DEBUG */
+
+  /* First, check if we are invoked by the TCP input processing
+     code. If so, we do not output anything. Instead, we rely on the
+     input processing code to call us when input processing is done
+     with. */
+  if (tcp_input_pcb == pcb) {
+    return ERR_OK;
+  }
+
+  wnd = LWIP_MIN(pcb->snd_wnd, pcb->cwnd);
+
+  seg = pcb->unsent;
+
+  /* If the TF_ACK_NOW flag is set and no data will be sent (either
+   * because the ->unsent queue is empty or because the window does
+   * not allow it), construct an empty ACK segment and send it.
+   *
+   * If data is to be sent, we will just piggyback the ACK (see below).
+   */
+  if (pcb->flags & TF_ACK_NOW &&
+     (seg == NULL ||
+      ntohl(seg->tcphdr->seqno) - pcb->lastack + seg->len > wnd)) {
+     return tcp_send_empty_ack(pcb);
+  }
+
+  /* useg should point to last segment on unacked queue */
+  useg = pcb->unacked;
+  if (useg != NULL) {
+    for (; useg->next != NULL; useg = useg->next);
+  }
+
+#if TCP_OUTPUT_DEBUG
+  if (seg == NULL) {
+    LWIP_DEBUGF(TCP_OUTPUT_DEBUG, ("tcp_output: nothing to send (%p)\n",
+                                   (void*)pcb->unsent));
+  }
+#endif /* TCP_OUTPUT_DEBUG */
+#if TCP_CWND_DEBUG
+  if (seg == NULL) {
+    LWIP_DEBUGF(TCP_CWND_DEBUG, ("tcp_output: snd_wnd %"U16_F
+                                 ", cwnd %"U16_F", wnd %"U32_F
+                                 ", seg == NULL, ack %"U32_F"\n",
+                                 pcb->snd_wnd, pcb->cwnd, wnd, pcb->lastack));
+  } else {
+    LWIP_DEBUGF(TCP_CWND_DEBUG, 
+                ("tcp_output: snd_wnd %"U16_F", cwnd %"U16_F", wnd %"U32_F
+                 ", effwnd %"U32_F", seq %"U32_F", ack %"U32_F"\n",
+                 pcb->snd_wnd, pcb->cwnd, wnd,
+                 ntohl(seg->tcphdr->seqno) - pcb->lastack + seg->len,
+                 ntohl(seg->tcphdr->seqno), pcb->lastack));
+  }
+#endif /* TCP_CWND_DEBUG */
+  /* data available and window allows it to be sent? */
+  while (seg != NULL &&
+         ntohl(seg->tcphdr->seqno) - pcb->lastack + seg->len <= wnd) {
+    LWIP_ASSERT("RST not expected here!", 
+                (TCPH_FLAGS(seg->tcphdr) & TCP_RST) == 0);
+    /* Stop sending if the nagle algorithm would prevent it
+     * Don't stop:
+     * - if tcp_write had a memory error before (prevent delayed ACK timeout) or
+     * - if FIN was already enqueued for this PCB (SYN is always alone in a segment -
+     *   either seg->next != NULL or pcb->unacked == NULL;
+     *   RST is no sent using tcp_write/tcp_output.
+     */
+    if((tcp_do_output_nagle(pcb) == 0) &&
+      ((pcb->flags & (TF_NAGLEMEMERR | TF_FIN)) == 0)){
+      break;
+    }
+#if TCP_CWND_DEBUG
+    LWIP_DEBUGF(TCP_CWND_DEBUG, ("tcp_output: snd_wnd %"U16_F", cwnd %"U16_F", wnd %"U32_F", effwnd %"U32_F", seq %"U32_F", ack %"U32_F", i %"S16_F"\n",
+                            pcb->snd_wnd, pcb->cwnd, wnd,
+                            ntohl(seg->tcphdr->seqno) + seg->len -
+                            pcb->lastack,
+                            ntohl(seg->tcphdr->seqno), pcb->lastack, i));
+    ++i;
+#endif /* TCP_CWND_DEBUG */
+
+    pcb->unsent = seg->next;
+
+    if (pcb->state != SYN_SENT) {
+      TCPH_SET_FLAG(seg->tcphdr, TCP_ACK);
+      pcb->flags &= ~(TF_ACK_DELAY | TF_ACK_NOW);
+    }
+
+    tcp_output_segment(seg, pcb);
+       
+    snd_nxt = ntohl(seg->tcphdr->seqno) + TCP_TCPLEN(seg);
+    
+    LWIP_DEBUGF(TCP_OUTPUT_DEBUG, ("tcp_output: pcb->snd_nxt was %"U32_F" seqno=%"U32_F" len=%"U32_F" new snd_nxt=%"U32_F"\n", //DG
+                                    pcb->snd_nxt, ntohl(seg->tcphdr->seqno), TCP_TCPLEN(seg), snd_nxt));
+    
+    if (TCP_SEQ_LT(pcb->snd_nxt, snd_nxt)) {
+      pcb->snd_nxt = snd_nxt;
+    }
+    /* put segment on unacknowledged list if length > 0 */
+    if (TCP_TCPLEN(seg) > 0) {
+      seg->next = NULL;
+      /* unacked list is empty? */
+      if (pcb->unacked == NULL) {
+        pcb->unacked = seg;
+        useg = seg;
+      /* unacked list is not empty? */
+      } else {
+        /* In the case of fast retransmit, the packet should not go to the tail
+         * of the unacked queue, but rather somewhere before it. We need to check for
+         * this case. -STJ Jul 27, 2004 */
+        if (TCP_SEQ_LT(ntohl(seg->tcphdr->seqno), ntohl(useg->tcphdr->seqno))) {
+          /* add segment to before tail of unacked list, keeping the list sorted */
+          struct tcp_seg **cur_seg = &(pcb->unacked);
+          while (*cur_seg &&
+            TCP_SEQ_LT(ntohl((*cur_seg)->tcphdr->seqno), ntohl(seg->tcphdr->seqno))) {
+              cur_seg = &((*cur_seg)->next );
+          }
+          seg->next = (*cur_seg);
+          (*cur_seg) = seg;
+        } else {
+          /* add segment to tail of unacked list */
+          useg->next = seg;
+          useg = useg->next;
+        }
+      }
+    /* do not queue empty segments on the unacked list */
+    } else {
+      tcp_seg_free(seg);
+    }
+    seg = pcb->unsent;
+  }
+#if TCP_OVERSIZE
+  if (pcb->unsent == NULL) {
+    /* last unsent has been removed, reset unsent_oversize */
+    pcb->unsent_oversize = 0;
+  }
+#endif /* TCP_OVERSIZE */
+
+  if (seg != NULL && pcb->persist_backoff == 0 && 
+      ntohl(seg->tcphdr->seqno) - pcb->lastack + seg->len > pcb->snd_wnd) {
+    /* prepare for persist timer */
+    pcb->persist_cnt = 0;
+    pcb->persist_backoff = 1;
+  }
+
+  pcb->flags &= ~TF_NAGLEMEMERR;
+  return ERR_OK;
+}
+
+/**
+ * Called by tcp_output() to actually send a TCP segment over IP.
+ *
+ * @param seg the tcp_seg to send
+ * @param pcb the tcp_pcb for the TCP connection used to send the segment
+ */
+static void
+tcp_output_segment(struct tcp_seg *seg, struct tcp_pcb *pcb)
+{
+  u16_t len;
+  struct netif *netif;
+  u32_t *opts;
+
+  /** @bug Exclude retransmitted segments from this count. */
+  snmp_inc_tcpoutsegs();
+
+  /* The TCP header has already been constructed, but the ackno and
+   wnd fields remain. */
+  seg->tcphdr->ackno = htonl(pcb->rcv_nxt);
+
+  /* advertise our receive window size in this TCP segment */
+  seg->tcphdr->wnd = htons(pcb->rcv_ann_wnd);
+
+  pcb->rcv_ann_right_edge = pcb->rcv_nxt + pcb->rcv_ann_wnd;
+
+  /* Add any requested options.  NB MSS option is only set on SYN
+     packets, so ignore it here */
+  LWIP_ASSERT("seg->tcphdr not aligned", ((mem_ptr_t)(seg->tcphdr + 1) % 4) == 0);
+  opts = (u32_t *)(void *)(seg->tcphdr + 1);
+  if (seg->flags & TF_SEG_OPTS_MSS) {
+    TCP_BUILD_MSS_OPTION(*opts);
+    opts += 1;
+  }
+#if LWIP_TCP_TIMESTAMPS
+  pcb->ts_lastacksent = pcb->rcv_nxt;
+
+  if (seg->flags & TF_SEG_OPTS_TS) {
+    tcp_build_timestamp_option(pcb, opts);
+    opts += 3;
+  }
+#endif
+
+  /* If we don't have a local IP address, we get one by
+     calling ip_route(). */
+  if (ip_addr_isany(&(pcb->local_ip))) {
+    netif = ip_route(&(pcb->remote_ip));
+    if (netif == NULL) {
+      return;
+    }
+    ip_addr_copy(pcb->local_ip, netif->ip_addr);
+  }
+
+  /* Set retransmission timer running if it is not currently enabled */
+  if(pcb->rtime == -1) {
+    pcb->rtime = 0;
+  }
+
+  if (pcb->rttest == 0) {
+    pcb->rttest = tcp_ticks;
+    pcb->rtseq = ntohl(seg->tcphdr->seqno);
+
+    LWIP_DEBUGF(TCP_RTO_DEBUG, ("tcp_output_segment: rtseq %"U32_F"\n", pcb->rtseq));
+  }
+  LWIP_DEBUGF(TCP_OUTPUT_DEBUG, ("tcp_output_segment: %"U32_F":%"U32_F"\n",
+          htonl(seg->tcphdr->seqno), htonl(seg->tcphdr->seqno) +
+          seg->len));
+
+  len = (u16_t)((u8_t *)seg->tcphdr - (u8_t *)seg->p->payload);
+
+  seg->p->len -= len;
+  seg->p->tot_len -= len;
+
+  seg->p->payload = seg->tcphdr;
+
+  seg->tcphdr->chksum = 0;
+#if CHECKSUM_GEN_TCP
+#if TCP_CHECKSUM_ON_COPY
+  {
+    u32_t acc;
+#if TCP_CHECKSUM_ON_COPY_SANITY_CHECK
+    u16_t chksum_slow = inet_chksum_pseudo(seg->p, &(pcb->local_ip),
+           &(pcb->remote_ip),
+           IP_PROTO_TCP, seg->p->tot_len);
+#endif /* TCP_CHECKSUM_ON_COPY_SANITY_CHECK */
+    if ((seg->flags & TF_SEG_DATA_CHECKSUMMED) == 0) {
+      LWIP_ASSERT("data included but not checksummed",
+        seg->p->tot_len == (TCPH_HDRLEN(seg->tcphdr) * 4));
+    }
+
+    /* rebuild TCP header checksum (TCP header changes for retransmissions!) */
+    acc = inet_chksum_pseudo_partial(seg->p, &(pcb->local_ip),
+             &(pcb->remote_ip),
+             IP_PROTO_TCP, seg->p->tot_len, TCPH_HDRLEN(seg->tcphdr) * 4);
+    /* add payload checksum */
+    if (seg->chksum_swapped) {
+      seg->chksum = SWAP_BYTES_IN_WORD(seg->chksum);
+      seg->chksum_swapped = 0;
+    }
+    acc += (u16_t)~(seg->chksum);
+    seg->tcphdr->chksum = FOLD_U32T(acc);
+#if TCP_CHECKSUM_ON_COPY_SANITY_CHECK
+    if (chksum_slow != seg->tcphdr->chksum) {
+      LWIP_DEBUGF(TCP_DEBUG | LWIP_DBG_LEVEL_WARNING,
+                  ("tcp_output_segment: calculated checksum is %"X16_F" instead of %"X16_F"\n",
+                  seg->tcphdr->chksum, chksum_slow));
+      seg->tcphdr->chksum = chksum_slow;
+    }
+#endif /* TCP_CHECKSUM_ON_COPY_SANITY_CHECK */
+  }
+#else /* TCP_CHECKSUM_ON_COPY */
+  seg->tcphdr->chksum = inet_chksum_pseudo(seg->p, &(pcb->local_ip),
+         &(pcb->remote_ip),
+         IP_PROTO_TCP, seg->p->tot_len);
+#endif /* TCP_CHECKSUM_ON_COPY */
+#endif /* CHECKSUM_GEN_TCP */
+  TCP_STATS_INC(tcp.xmit);
+  
+  LWIP_DEBUGF(TCP_OUTPUT_DEBUG, ("tcp_output_segment: Before ip_out seqno = %"U32_F"\n",
+        htonl(seg->tcphdr->seqno))); //DG
+
+#if LWIP_NETIF_HWADDRHINT
+  ip_output_hinted(seg->p, &(pcb->local_ip), &(pcb->remote_ip), pcb->ttl, pcb->tos,
+      IP_PROTO_TCP, &(pcb->addr_hint));
+#else /* LWIP_NETIF_HWADDRHINT*/
+  ip_output(seg->p, &(pcb->local_ip), &(pcb->remote_ip), pcb->ttl, pcb->tos,
+      IP_PROTO_TCP);
+#endif /* LWIP_NETIF_HWADDRHINT*/
+
+  LWIP_DEBUGF(TCP_OUTPUT_DEBUG, ("tcp_output_segment: After ip_out seqno = %"U32_F"\n",
+        htonl(seg->tcphdr->seqno))); //DG
+
+
+}
+
+/**
+ * Send a TCP RESET packet (empty segment with RST flag set) either to
+ * abort a connection or to show that there is no matching local connection
+ * for a received segment.
+ *
+ * Called by tcp_abort() (to abort a local connection), tcp_input() (if no
+ * matching local pcb was found), tcp_listen_input() (if incoming segment
+ * has ACK flag set) and tcp_process() (received segment in the wrong state)
+ *
+ * Since a RST segment is in most cases not sent for an active connection,
+ * tcp_rst() has a number of arguments that are taken from a tcp_pcb for
+ * most other segment output functions.
+ *
+ * @param seqno the sequence number to use for the outgoing segment
+ * @param ackno the acknowledge number to use for the outgoing segment
+ * @param local_ip the local IP address to send the segment from
+ * @param remote_ip the remote IP address to send the segment to
+ * @param local_port the local TCP port to send the segment from
+ * @param remote_port the remote TCP port to send the segment to
+ */
+void
+tcp_rst(u32_t seqno, u32_t ackno,
+  ip_addr_t *local_ip, ip_addr_t *remote_ip,
+  u16_t local_port, u16_t remote_port)
+{
+  struct pbuf *p;
+  struct tcp_hdr *tcphdr;
+  p = pbuf_alloc(PBUF_IP, TCP_HLEN, PBUF_RAM);
+  if (p == NULL) {
+      LWIP_DEBUGF(TCP_DEBUG, ("tcp_rst: could not allocate memory for pbuf\n"));
+      return;
+  }
+  LWIP_ASSERT("check that first pbuf can hold struct tcp_hdr",
+              (p->len >= sizeof(struct tcp_hdr)));
+
+  tcphdr = (struct tcp_hdr *)p->payload;
+  tcphdr->src = htons(local_port);
+  tcphdr->dest = htons(remote_port);
+  tcphdr->seqno = htonl(seqno);
+  tcphdr->ackno = htonl(ackno);
+  TCPH_HDRLEN_FLAGS_SET(tcphdr, TCP_HLEN/4, TCP_RST | TCP_ACK);
+  tcphdr->wnd = PP_HTONS(TCP_WND);
+  tcphdr->chksum = 0;
+  tcphdr->urgp = 0;
+
+#if CHECKSUM_GEN_TCP
+  tcphdr->chksum = inet_chksum_pseudo(p, local_ip, remote_ip,
+              IP_PROTO_TCP, p->tot_len);
+#endif
+  TCP_STATS_INC(tcp.xmit);
+  snmp_inc_tcpoutrsts();
+   /* Send output with hardcoded TTL since we have no access to the pcb */
+  ip_output(p, local_ip, remote_ip, TCP_TTL, 0, IP_PROTO_TCP);
+  pbuf_free(p);
+  LWIP_DEBUGF(TCP_RST_DEBUG, ("tcp_rst: seqno %"U32_F" ackno %"U32_F".\n", seqno, ackno));
+}
+
+/**
+ * Requeue all unacked segments for retransmission
+ *
+ * Called by tcp_slowtmr() for slow retransmission.
+ *
+ * @param pcb the tcp_pcb for which to re-enqueue all unacked segments
+ */
+void
+tcp_rexmit_rto(struct tcp_pcb *pcb)
+{
+  struct tcp_seg *seg;
+
+  if (pcb->unacked == NULL) {
+    return;
+  }
+
+  /* Move all unacked segments to the head of the unsent queue */
+  for (seg = pcb->unacked; seg->next != NULL; seg = seg->next);
+  /* concatenate unsent queue after unacked queue */
+  seg->next = pcb->unsent;
+  /* unsent queue is the concatenated queue (of unacked, unsent) */
+  pcb->unsent = pcb->unacked;
+  /* unacked queue is now empty */
+  pcb->unacked = NULL;
+
+  /* increment number of retransmissions */
+  ++pcb->nrtx;
+
+  /* Don't take any RTT measurements after retransmitting. */
+  pcb->rttest = 0;
+
+  /* Do the actual retransmission */
+  tcp_output(pcb);
+}
+
+/**
+ * Requeue the first unacked segment for retransmission
+ *
+ * Called by tcp_receive() for fast retramsmit.
+ *
+ * @param pcb the tcp_pcb for which to retransmit the first unacked segment
+ */
+void
+tcp_rexmit(struct tcp_pcb *pcb)
+{
+  struct tcp_seg *seg;
+  struct tcp_seg **cur_seg;
+
+  if (pcb->unacked == NULL) {
+    return;
+  }
+
+  /* Move the first unacked segment to the unsent queue */
+  /* Keep the unsent queue sorted. */
+  seg = pcb->unacked;
+  pcb->unacked = seg->next;
+
+  cur_seg = &(pcb->unsent);
+  while (*cur_seg &&
+    TCP_SEQ_LT(ntohl((*cur_seg)->tcphdr->seqno), ntohl(seg->tcphdr->seqno))) {
+      cur_seg = &((*cur_seg)->next );
+  }
+  seg->next = *cur_seg;
+  *cur_seg = seg;
+
+  ++pcb->nrtx;
+
+  /* Don't take any rtt measurements after retransmitting. */
+  pcb->rttest = 0;
+
+  /* Do the actual retransmission. */
+  snmp_inc_tcpretranssegs();
+  /* No need to call tcp_output: we are always called from tcp_input()
+     and thus tcp_output directly returns. */
+}
+
+
+/**
+ * Handle retransmission after three dupacks received
+ *
+ * @param pcb the tcp_pcb for which to retransmit the first unacked segment
+ */
+void 
+tcp_rexmit_fast(struct tcp_pcb *pcb)
+{
+  if (pcb->unacked != NULL && !(pcb->flags & TF_INFR)) {
+    /* This is fast retransmit. Retransmit the first unacked segment. */
+    LWIP_DEBUGF(TCP_FR_DEBUG, 
+                ("tcp_receive: dupacks %"U16_F" (%"U32_F
+                 "), fast retransmit %"U32_F"\n",
+                 (u16_t)pcb->dupacks, pcb->lastack,
+                 ntohl(pcb->unacked->tcphdr->seqno)));
+    tcp_rexmit(pcb);
+
+    /* Set ssthresh to half of the minimum of the current
+     * cwnd and the advertised window */
+    if (pcb->cwnd > pcb->snd_wnd) {
+      pcb->ssthresh = pcb->snd_wnd / 2;
+    } else {
+      pcb->ssthresh = pcb->cwnd / 2;
+    }
+    
+    /* The minimum value for ssthresh should be 2 MSS */
+    if (pcb->ssthresh < 2*pcb->mss) {
+      LWIP_DEBUGF(TCP_FR_DEBUG, 
+                  ("tcp_receive: The minimum value for ssthresh %"U16_F
+                   " should be min 2 mss %"U16_F"...\n",
+                   pcb->ssthresh, 2*pcb->mss));
+      pcb->ssthresh = 2*pcb->mss;
+    }
+    
+    pcb->cwnd = pcb->ssthresh + 3 * pcb->mss;
+    pcb->flags |= TF_INFR;
+  } 
+}
+
+
+/**
+ * Send keepalive packets to keep a connection active although
+ * no data is sent over it.
+ *
+ * Called by tcp_slowtmr()
+ *
+ * @param pcb the tcp_pcb for which to send a keepalive packet
+ */
+void
+tcp_keepalive(struct tcp_pcb *pcb)
+{
+  struct pbuf *p;
+  struct tcp_hdr *tcphdr;
+
+  LWIP_DEBUGF(TCP_DEBUG, ("tcp_keepalive: sending KEEPALIVE probe to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
+                          ip4_addr1_16(&pcb->remote_ip), ip4_addr2_16(&pcb->remote_ip),
+                          ip4_addr3_16(&pcb->remote_ip), ip4_addr4_16(&pcb->remote_ip)));
+
+  LWIP_DEBUGF(TCP_DEBUG, ("tcp_keepalive: tcp_ticks %"U32_F"   pcb->tmr %"U32_F" pcb->keep_cnt_sent %"U16_F"\n", 
+                          tcp_ticks, pcb->tmr, pcb->keep_cnt_sent));
+   
+  p = tcp_output_alloc_header(pcb, 0, 0, htonl(pcb->snd_nxt - 1));
+  if(p == NULL) {
+    LWIP_DEBUGF(TCP_DEBUG, 
+                ("tcp_keepalive: could not allocate memory for pbuf\n"));
+    return;
+  }
+  tcphdr = (struct tcp_hdr *)p->payload;
+
+#if CHECKSUM_GEN_TCP
+  tcphdr->chksum = inet_chksum_pseudo(p, &pcb->local_ip, &pcb->remote_ip,
+                                      IP_PROTO_TCP, p->tot_len);
+#endif
+  TCP_STATS_INC(tcp.xmit);
+
+  /* Send output to IP */
+#if LWIP_NETIF_HWADDRHINT
+  ip_output_hinted(p, &pcb->local_ip, &pcb->remote_ip, pcb->ttl, 0, IP_PROTO_TCP,
+    &(pcb->addr_hint));
+#else /* LWIP_NETIF_HWADDRHINT*/
+  ip_output(p, &pcb->local_ip, &pcb->remote_ip, pcb->ttl, 0, IP_PROTO_TCP);
+#endif /* LWIP_NETIF_HWADDRHINT*/
+
+  pbuf_free(p);
+
+  LWIP_DEBUGF(TCP_DEBUG, ("tcp_keepalive: seqno %"U32_F" ackno %"U32_F".\n",
+                          pcb->snd_nxt - 1, pcb->rcv_nxt));
+}
+
+
+/**
+ * Send persist timer zero-window probes to keep a connection active
+ * when a window update is lost.
+ *
+ * Called by tcp_slowtmr()
+ *
+ * @param pcb the tcp_pcb for which to send a zero-window probe packet
+ */
+void
+tcp_zero_window_probe(struct tcp_pcb *pcb)
+{
+  struct pbuf *p;
+  struct tcp_hdr *tcphdr;
+  struct tcp_seg *seg;
+  u16_t len;
+  u8_t is_fin;
+
+  LWIP_DEBUGF(TCP_DEBUG, 
+              ("tcp_zero_window_probe: sending ZERO WINDOW probe to %"
+               U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
+               ip4_addr1_16(&pcb->remote_ip), ip4_addr2_16(&pcb->remote_ip),
+               ip4_addr3_16(&pcb->remote_ip), ip4_addr4_16(&pcb->remote_ip)));
+
+  LWIP_DEBUGF(TCP_DEBUG, 
+              ("tcp_zero_window_probe: tcp_ticks %"U32_F
+               "   pcb->tmr %"U32_F" pcb->keep_cnt_sent %"U16_F"\n", 
+               tcp_ticks, pcb->tmr, pcb->keep_cnt_sent));
+
+  seg = pcb->unacked;
+
+  if(seg == NULL) {
+    seg = pcb->unsent;
+  }
+  if(seg == NULL) {
+    return;
+  }
+
+  is_fin = ((TCPH_FLAGS(seg->tcphdr) & TCP_FIN) != 0) && (seg->len == 0);
+  /* we want to send one seqno: either FIN or data (no options) */
+  len = is_fin ? 0 : 1;
+
+  p = tcp_output_alloc_header(pcb, 0, len, seg->tcphdr->seqno);
+  if(p == NULL) {
+    LWIP_DEBUGF(TCP_DEBUG, ("tcp_zero_window_probe: no memory for pbuf\n"));
+    return;
+  }
+  tcphdr = (struct tcp_hdr *)p->payload;
+
+  if (is_fin) {
+    /* FIN segment, no data */
+    TCPH_FLAGS_SET(tcphdr, TCP_ACK | TCP_FIN);
+  } else {
+    /* Data segment, copy in one byte from the head of the unacked queue */
+    *((char *)p->payload + TCP_HLEN) = *(char *)seg->dataptr;
+  }
+
+#if CHECKSUM_GEN_TCP
+  tcphdr->chksum = inet_chksum_pseudo(p, &pcb->local_ip, &pcb->remote_ip,
+                                      IP_PROTO_TCP, p->tot_len);
+#endif
+  TCP_STATS_INC(tcp.xmit);
+
+  /* Send output to IP */
+#if LWIP_NETIF_HWADDRHINT
+  ip_output_hinted(p, &pcb->local_ip, &pcb->remote_ip, pcb->ttl, 0, IP_PROTO_TCP,
+    &(pcb->addr_hint));
+#else /* LWIP_NETIF_HWADDRHINT*/
+  ip_output(p, &pcb->local_ip, &pcb->remote_ip, pcb->ttl, 0, IP_PROTO_TCP);
+#endif /* LWIP_NETIF_HWADDRHINT*/
+
+  pbuf_free(p);
+
+  LWIP_DEBUGF(TCP_DEBUG, ("tcp_zero_window_probe: seqno %"U32_F
+                          " ackno %"U32_F".\n",
+                          pcb->snd_nxt - 1, pcb->rcv_nxt));
+}
+#endif /* LWIP_TCP */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/core/timers.c	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,483 @@
+/**
+ * @file
+ * Stack-internal timers implementation.
+ * This file includes timer callbacks for stack-internal timers as well as
+ * functions to set up or stop timers and check for expired timers.
+ *
+ */
+
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ *
+ * Author: Adam Dunkels <adam@sics.se>
+ *         Simon Goldschmidt
+ *
+ */
+
+#include "lwip/opt.h"
+
+#include "lwip/timers.h"
+
+#if LWIP_TIMERS
+
+#include "lwip/def.h"
+#include "lwip/memp.h"
+#include "lwip/tcpip.h"
+
+#include "lwip/tcp_impl.h"
+#include "lwip/ip_frag.h"
+#include "netif/etharp.h"
+#include "lwip/dhcp.h"
+#include "lwip/autoip.h"
+#include "lwip/igmp.h"
+#include "lwip/dns.h"
+
+
+/** The one and only timeout list */
+static struct sys_timeo *next_timeout;
+#if NO_SYS
+static u32_t timeouts_last_time;
+#endif /* NO_SYS */
+
+#if LWIP_TCP
+/** global variable that shows if the tcp timer is currently scheduled or not */
+static int tcpip_tcp_timer_active;
+
+/**
+ * Timer callback function that calls tcp_tmr() and reschedules itself.
+ *
+ * @param arg unused argument
+ */
+static void
+tcpip_tcp_timer(void *arg)
+{
+  LWIP_UNUSED_ARG(arg);
+
+  /* call TCP timer handler */
+  tcp_tmr();
+  /* timer still needed? */
+  if (tcp_active_pcbs || tcp_tw_pcbs) {
+    /* restart timer */
+    sys_timeout(TCP_TMR_INTERVAL, tcpip_tcp_timer, NULL);
+  } else {
+    /* disable timer */
+    tcpip_tcp_timer_active = 0;
+  }
+}
+
+/**
+ * Called from TCP_REG when registering a new PCB:
+ * the reason is to have the TCP timer only running when
+ * there are active (or time-wait) PCBs.
+ */
+void
+tcp_timer_needed(void)
+{
+  /* timer is off but needed again? */
+  if (!tcpip_tcp_timer_active && (tcp_active_pcbs || tcp_tw_pcbs)) {
+    /* enable and start timer */
+    tcpip_tcp_timer_active = 1;
+    sys_timeout(TCP_TMR_INTERVAL, tcpip_tcp_timer, NULL);
+  }
+}
+#endif /* LWIP_TCP */
+
+#if IP_REASSEMBLY
+/**
+ * Timer callback function that calls ip_reass_tmr() and reschedules itself.
+ *
+ * @param arg unused argument
+ */
+static void
+ip_reass_timer(void *arg)
+{
+  LWIP_UNUSED_ARG(arg);
+  LWIP_DEBUGF(TIMERS_DEBUG, ("tcpip: ip_reass_tmr()\n"));
+  ip_reass_tmr();
+  sys_timeout(IP_TMR_INTERVAL, ip_reass_timer, NULL);
+}
+#endif /* IP_REASSEMBLY */
+
+#if LWIP_ARP
+/**
+ * Timer callback function that calls etharp_tmr() and reschedules itself.
+ *
+ * @param arg unused argument
+ */
+static void
+arp_timer(void *arg)
+{
+  LWIP_UNUSED_ARG(arg);
+  LWIP_DEBUGF(TIMERS_DEBUG, ("tcpip: etharp_tmr()\n"));
+  etharp_tmr();
+  sys_timeout(ARP_TMR_INTERVAL, arp_timer, NULL);
+}
+#endif /* LWIP_ARP */
+
+#if LWIP_DHCP
+/**
+ * Timer callback function that calls dhcp_coarse_tmr() and reschedules itself.
+ *
+ * @param arg unused argument
+ */
+static void
+dhcp_timer_coarse(void *arg)
+{
+  LWIP_UNUSED_ARG(arg);
+  LWIP_DEBUGF(TIMERS_DEBUG, ("tcpip: dhcp_coarse_tmr()\n"));
+  dhcp_coarse_tmr();
+  sys_timeout(DHCP_COARSE_TIMER_MSECS, dhcp_timer_coarse, NULL);
+}
+
+/**
+ * Timer callback function that calls dhcp_fine_tmr() and reschedules itself.
+ *
+ * @param arg unused argument
+ */
+static void
+dhcp_timer_fine(void *arg)
+{
+  LWIP_UNUSED_ARG(arg);
+  LWIP_DEBUGF(TIMERS_DEBUG, ("tcpip: dhcp_fine_tmr()\n"));
+  dhcp_fine_tmr();
+  sys_timeout(DHCP_FINE_TIMER_MSECS, dhcp_timer_fine, NULL);
+}
+#endif /* LWIP_DHCP */
+
+#if LWIP_AUTOIP
+/**
+ * Timer callback function that calls autoip_tmr() and reschedules itself.
+ *
+ * @param arg unused argument
+ */
+static void
+autoip_timer(void *arg)
+{
+  LWIP_UNUSED_ARG(arg);
+  LWIP_DEBUGF(TIMERS_DEBUG, ("tcpip: autoip_tmr()\n"));
+  autoip_tmr();
+  sys_timeout(AUTOIP_TMR_INTERVAL, autoip_timer, NULL);
+}
+#endif /* LWIP_AUTOIP */
+
+#if LWIP_IGMP
+/**
+ * Timer callback function that calls igmp_tmr() and reschedules itself.
+ *
+ * @param arg unused argument
+ */
+static void
+igmp_timer(void *arg)
+{
+  LWIP_UNUSED_ARG(arg);
+  LWIP_DEBUGF(TIMERS_DEBUG, ("tcpip: igmp_tmr()\n"));
+  igmp_tmr();
+  sys_timeout(IGMP_TMR_INTERVAL, igmp_timer, NULL);
+}
+#endif /* LWIP_IGMP */
+
+#if LWIP_DNS
+/**
+ * Timer callback function that calls dns_tmr() and reschedules itself.
+ *
+ * @param arg unused argument
+ */
+static void
+dns_timer(void *arg)
+{
+  LWIP_UNUSED_ARG(arg);
+  LWIP_DEBUGF(TIMERS_DEBUG, ("tcpip: dns_tmr()\n"));
+  dns_tmr();
+  sys_timeout(DNS_TMR_INTERVAL, dns_timer, NULL);
+}
+#endif /* LWIP_DNS */
+
+/** Initialize this module */
+void sys_timeouts_init(void)
+{
+  next_timeout = NULL;
+#if IP_REASSEMBLY
+  sys_timeout(IP_TMR_INTERVAL, ip_reass_timer, NULL);
+#endif /* IP_REASSEMBLY */
+#if LWIP_ARP
+  sys_timeout(ARP_TMR_INTERVAL, arp_timer, NULL);
+#endif /* LWIP_ARP */
+#if LWIP_DHCP
+  sys_timeout(DHCP_COARSE_TIMER_MSECS, dhcp_timer_coarse, NULL);
+  sys_timeout(DHCP_FINE_TIMER_MSECS, dhcp_timer_fine, NULL);
+#endif /* LWIP_DHCP */
+#if LWIP_AUTOIP
+  sys_timeout(AUTOIP_TMR_INTERVAL, autoip_timer, NULL);
+#endif /* LWIP_AUTOIP */
+#if LWIP_IGMP
+  sys_timeout(IGMP_TMR_INTERVAL, igmp_timer, NULL);
+#endif /* LWIP_IGMP */
+#if LWIP_DNS
+  sys_timeout(DNS_TMR_INTERVAL, dns_timer, NULL);
+#endif /* LWIP_DNS */
+
+#if NO_SYS
+  /* Initialise timestamp for sys_check_timeouts */
+  timeouts_last_time = sys_now();
+#endif
+}
+
+/**
+ * Create a one-shot timer (aka timeout). Timeouts are processed in the
+ * following cases:
+ * - while waiting for a message using sys_timeouts_mbox_fetch()
+ * - by calling sys_check_timeouts() (NO_SYS==1 only)
+ *
+ * @param msecs time in milliseconds after that the timer should expire
+ * @param handler callback function to call when msecs have elapsed
+ * @param arg argument to pass to the callback function
+ */
+#if LWIP_DEBUG_TIMERNAMES
+void
+sys_timeout_debug(u32_t msecs, sys_timeout_handler handler, void *arg, const char* handler_name)
+#else /* LWIP_DEBUG_TIMERNAMES */
+void
+sys_timeout(u32_t msecs, sys_timeout_handler handler, void *arg)
+#endif /* LWIP_DEBUG_TIMERNAMES */
+{
+  struct sys_timeo *timeout, *t;
+
+  timeout = (struct sys_timeo *)memp_malloc(MEMP_SYS_TIMEOUT);
+  if (timeout == NULL) {
+    LWIP_ASSERT("sys_timeout: timeout != NULL, pool MEMP_SYS_TIMEOUT is empty", timeout != NULL);
+    return;
+  }
+  timeout->next = NULL;
+  timeout->h = handler;
+  timeout->arg = arg;
+  timeout->time = msecs;
+#if LWIP_DEBUG_TIMERNAMES
+  timeout->handler_name = handler_name;
+  LWIP_DEBUGF(TIMERS_DEBUG, ("sys_timeout: %p msecs=%"U32_F" handler=%s arg=%p\n",
+    (void *)timeout, msecs, handler_name, (void *)arg));
+#endif /* LWIP_DEBUG_TIMERNAMES */
+
+  if (next_timeout == NULL) {
+    next_timeout = timeout;
+    return;
+  }
+
+  if (next_timeout->time > msecs) {
+    next_timeout->time -= msecs;
+    timeout->next = next_timeout;
+    next_timeout = timeout;
+  } else {
+    for(t = next_timeout; t != NULL; t = t->next) {
+      timeout->time -= t->time;
+      if (t->next == NULL || t->next->time > timeout->time) {
+        if (t->next != NULL) {
+          t->next->time -= timeout->time;
+        }
+        timeout->next = t->next;
+        t->next = timeout;
+        break;
+      }
+    }
+  }
+}
+
+/**
+ * Go through timeout list (for this task only) and remove the first matching
+ * entry, even though the timeout has not triggered yet.
+ *
+ * @note This function only works as expected if there is only one timeout
+ * calling 'handler' in the list of timeouts.
+ *
+ * @param handler callback function that would be called by the timeout
+ * @param arg callback argument that would be passed to handler
+*/
+void
+sys_untimeout(sys_timeout_handler handler, void *arg)
+{
+  struct sys_timeo *prev_t, *t;
+
+  if (next_timeout == NULL) {
+    return;
+  }
+
+  for (t = next_timeout, prev_t = NULL; t != NULL; prev_t = t, t = t->next) {
+    if ((t->h == handler) && (t->arg == arg)) {
+      /* We have a match */
+      /* Unlink from previous in list */
+      if (prev_t == NULL) {
+        next_timeout = t->next;
+      } else {
+        prev_t->next = t->next;
+      }
+      /* If not the last one, add time of this one back to next */
+      if (t->next != NULL) {
+        t->next->time += t->time;
+      }
+      memp_free(MEMP_SYS_TIMEOUT, t);
+      return;
+    }
+  }
+  return;
+}
+
+#if NO_SYS
+
+/** Handle timeouts for NO_SYS==1 (i.e. without using
+ * tcpip_thread/sys_timeouts_mbox_fetch(). Uses sys_now() to call timeout
+ * handler functions when timeouts expire.
+ *
+ * Must be called periodically from your main loop.
+ */
+void
+sys_check_timeouts(void)
+{
+  struct sys_timeo *tmptimeout;
+  u32_t diff;
+  sys_timeout_handler handler;
+  void *arg;
+  int had_one;
+  u32_t now;
+
+  now = sys_now();
+  if (next_timeout) {
+    /* this cares for wraparounds */
+    diff = LWIP_U32_DIFF(now, timeouts_last_time);
+    do
+    {
+      had_one = 0;
+      tmptimeout = next_timeout;
+      if (tmptimeout->time <= diff) {
+        /* timeout has expired */
+        had_one = 1;
+        timeouts_last_time = now;
+        diff -= tmptimeout->time;
+        next_timeout = tmptimeout->next;
+        handler = tmptimeout->h;
+        arg = tmptimeout->arg;
+#if LWIP_DEBUG_TIMERNAMES
+        if (handler != NULL) {
+          LWIP_DEBUGF(TIMERS_DEBUG, ("sct calling h=%s arg=%p\n",
+            tmptimeout->handler_name, arg));
+        }
+#endif /* LWIP_DEBUG_TIMERNAMES */
+        memp_free(MEMP_SYS_TIMEOUT, tmptimeout);
+        if (handler != NULL) {
+          handler(arg);
+        }
+      }
+    /* repeat until all expired timers have been called */
+    }while(had_one);
+  }
+}
+
+/** Set back the timestamp of the last call to sys_check_timeouts()
+ * This is necessary if sys_check_timeouts() hasn't been called for a long
+ * time (e.g. while saving energy) to prevent all timer functions of that
+ * period being called.
+ */
+void
+sys_restart_timeouts(void)
+{
+  timeouts_last_time = sys_now();
+}
+
+#else /* NO_SYS */
+
+/**
+ * Wait (forever) for a message to arrive in an mbox.
+ * While waiting, timeouts are processed.
+ *
+ * @param mbox the mbox to fetch the message from
+ * @param msg the place to store the message
+ */
+void
+sys_timeouts_mbox_fetch(sys_mbox_t *mbox, void **msg)
+{
+  u32_t time_needed;
+  struct sys_timeo *tmptimeout;
+  sys_timeout_handler handler;
+  void *arg;
+
+ again:
+  if (!next_timeout) {
+    time_needed = sys_arch_mbox_fetch(mbox, msg, 0);
+  } else {
+    if (next_timeout->time > 0) {
+      time_needed = sys_arch_mbox_fetch(mbox, msg, next_timeout->time);
+    } else {
+      time_needed = SYS_ARCH_TIMEOUT;
+    }
+
+    if (time_needed == SYS_ARCH_TIMEOUT) {
+      /* If time == SYS_ARCH_TIMEOUT, a timeout occured before a message
+         could be fetched. We should now call the timeout handler and
+         deallocate the memory allocated for the timeout. */
+      tmptimeout = next_timeout;
+      next_timeout = tmptimeout->next;
+      handler = tmptimeout->h;
+      arg = tmptimeout->arg;
+#if LWIP_DEBUG_TIMERNAMES
+      if (handler != NULL) {
+        LWIP_DEBUGF(TIMERS_DEBUG, ("stmf calling h=%s arg=%p\n",
+          tmptimeout->handler_name, arg));
+      }
+#endif /* LWIP_DEBUG_TIMERNAMES */
+      memp_free(MEMP_SYS_TIMEOUT, tmptimeout);
+      if (handler != NULL) {
+        /* For LWIP_TCPIP_CORE_LOCKING, lock the core before calling the
+           timeout handler function. */
+        LOCK_TCPIP_CORE();
+        handler(arg);
+        UNLOCK_TCPIP_CORE();
+      }
+      LWIP_TCPIP_THREAD_ALIVE();
+
+      /* We try again to fetch a message from the mbox. */
+      goto again;
+    } else {
+      /* If time != SYS_ARCH_TIMEOUT, a message was received before the timeout
+         occured. The time variable is set to the number of
+         milliseconds we waited for the message. */
+      if (time_needed < next_timeout->time) {
+        next_timeout->time -= time_needed;
+      } else {
+        next_timeout->time = 0;
+      }
+    }
+  }
+}
+
+#endif /* NO_SYS */
+
+#else /* LWIP_TIMERS */
+/* Satisfy the TCP code which calls this function */
+void
+tcp_timer_needed(void)
+{
+}
+#endif /* LWIP_TIMERS */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/core/udp.c	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,962 @@
+/**
+ * @file
+ * User Datagram Protocol module
+ *
+ */
+
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ *
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+
+
+/* udp.c
+ *
+ * The code for the User Datagram Protocol UDP & UDPLite (RFC 3828).
+ *
+ */
+
+/* @todo Check the use of '(struct udp_pcb).chksum_len_rx'!
+ */
+
+#include "lwip/opt.h"
+
+#if LWIP_UDP /* don't build if not configured for use in lwipopts.h */
+
+#include "lwip/udp.h"
+#include "lwip/def.h"
+#include "lwip/memp.h"
+#include "lwip/inet_chksum.h"
+#include "lwip/ip_addr.h"
+#include "lwip/netif.h"
+#include "lwip/icmp.h"
+#include "lwip/stats.h"
+#include "lwip/snmp.h"
+#include "arch/perf.h"
+#include "lwip/dhcp.h"
+
+#include <string.h>
+
+/* The list of UDP PCBs */
+/* exported in udp.h (was static) */
+struct udp_pcb *udp_pcbs;
+
+/**
+ * Process an incoming UDP datagram.
+ *
+ * Given an incoming UDP datagram (as a chain of pbufs) this function
+ * finds a corresponding UDP PCB and hands over the pbuf to the pcbs
+ * recv function. If no pcb is found or the datagram is incorrect, the
+ * pbuf is freed.
+ *
+ * @param p pbuf to be demultiplexed to a UDP PCB.
+ * @param inp network interface on which the datagram was received.
+ *
+ */
+void
+udp_input(struct pbuf *p, struct netif *inp)
+{
+  struct udp_hdr *udphdr;
+  struct udp_pcb *pcb, *prev;
+  struct udp_pcb *uncon_pcb;
+  struct ip_hdr *iphdr;
+  u16_t src, dest;
+  u8_t local_match;
+  u8_t broadcast;
+
+  PERF_START;
+
+  UDP_STATS_INC(udp.recv);
+
+  iphdr = (struct ip_hdr *)p->payload;
+
+  /* Check minimum length (IP header + UDP header)
+   * and move payload pointer to UDP header */
+  if (p->tot_len < (IPH_HL(iphdr) * 4 + UDP_HLEN) || pbuf_header(p, -(s16_t)(IPH_HL(iphdr) * 4))) {
+    /* drop short packets */
+    LWIP_DEBUGF(UDP_DEBUG,
+                ("udp_input: short UDP datagram (%"U16_F" bytes) discarded\n", p->tot_len));
+    UDP_STATS_INC(udp.lenerr);
+    UDP_STATS_INC(udp.drop);
+    snmp_inc_udpinerrors();
+    pbuf_free(p);
+    goto end;
+  }
+
+  udphdr = (struct udp_hdr *)p->payload;
+
+  /* is broadcast packet ? */
+  broadcast = ip_addr_isbroadcast(&current_iphdr_dest, inp);
+
+  LWIP_DEBUGF(UDP_DEBUG, ("udp_input: received datagram of length %"U16_F"\n", p->tot_len));
+
+  /* convert src and dest ports to host byte order */
+  src = ntohs(udphdr->src);
+  dest = ntohs(udphdr->dest);
+
+  udp_debug_print(udphdr);
+
+  /* print the UDP source and destination */
+  LWIP_DEBUGF(UDP_DEBUG,
+              ("udp (%"U16_F".%"U16_F".%"U16_F".%"U16_F", %"U16_F") <-- "
+               "(%"U16_F".%"U16_F".%"U16_F".%"U16_F", %"U16_F")\n",
+               ip4_addr1_16(&iphdr->dest), ip4_addr2_16(&iphdr->dest),
+               ip4_addr3_16(&iphdr->dest), ip4_addr4_16(&iphdr->dest), ntohs(udphdr->dest),
+               ip4_addr1_16(&iphdr->src), ip4_addr2_16(&iphdr->src),
+               ip4_addr3_16(&iphdr->src), ip4_addr4_16(&iphdr->src), ntohs(udphdr->src)));
+
+#if LWIP_DHCP
+  pcb = NULL;
+  /* when LWIP_DHCP is active, packets to DHCP_CLIENT_PORT may only be processed by
+     the dhcp module, no other UDP pcb may use the local UDP port DHCP_CLIENT_PORT */
+  if (dest == DHCP_CLIENT_PORT) {
+    /* all packets for DHCP_CLIENT_PORT not coming from DHCP_SERVER_PORT are dropped! */
+    if (src == DHCP_SERVER_PORT) {
+      if ((inp->dhcp != NULL) && (inp->dhcp->pcb != NULL)) {
+        /* accept the packe if 
+           (- broadcast or directed to us) -> DHCP is link-layer-addressed, local ip is always ANY!
+           - inp->dhcp->pcb->remote == ANY or iphdr->src */
+        if ((ip_addr_isany(&inp->dhcp->pcb->remote_ip) ||
+           ip_addr_cmp(&(inp->dhcp->pcb->remote_ip), &current_iphdr_src))) {
+          pcb = inp->dhcp->pcb;
+        }
+      }
+    }
+  } else
+#endif /* LWIP_DHCP */
+  {
+    prev = NULL;
+    local_match = 0;
+    uncon_pcb = NULL;
+    /* Iterate through the UDP pcb list for a matching pcb.
+     * 'Perfect match' pcbs (connected to the remote port & ip address) are
+     * preferred. If no perfect match is found, the first unconnected pcb that
+     * matches the local port and ip address gets the datagram. */
+    for (pcb = udp_pcbs; pcb != NULL; pcb = pcb->next) {
+      local_match = 0;
+      /* print the PCB local and remote address */
+      LWIP_DEBUGF(UDP_DEBUG,
+                  ("pcb (%"U16_F".%"U16_F".%"U16_F".%"U16_F", %"U16_F") --- "
+                   "(%"U16_F".%"U16_F".%"U16_F".%"U16_F", %"U16_F")\n",
+                   ip4_addr1_16(&pcb->local_ip), ip4_addr2_16(&pcb->local_ip),
+                   ip4_addr3_16(&pcb->local_ip), ip4_addr4_16(&pcb->local_ip), pcb->local_port,
+                   ip4_addr1_16(&pcb->remote_ip), ip4_addr2_16(&pcb->remote_ip),
+                   ip4_addr3_16(&pcb->remote_ip), ip4_addr4_16(&pcb->remote_ip), pcb->remote_port));
+
+      /* compare PCB local addr+port to UDP destination addr+port */
+      if ((pcb->local_port == dest) &&
+          ((!broadcast && ip_addr_isany(&pcb->local_ip)) ||
+           ip_addr_cmp(&(pcb->local_ip), &current_iphdr_dest) ||
+#if LWIP_IGMP
+           ip_addr_ismulticast(&current_iphdr_dest) ||
+#endif /* LWIP_IGMP */
+#if IP_SOF_BROADCAST_RECV
+           (broadcast && (pcb->so_options & SOF_BROADCAST)))) {
+#else  /* IP_SOF_BROADCAST_RECV */
+           (broadcast))) {
+#endif /* IP_SOF_BROADCAST_RECV */
+        local_match = 1;
+        if ((uncon_pcb == NULL) && 
+            ((pcb->flags & UDP_FLAGS_CONNECTED) == 0)) {
+          /* the first unconnected matching PCB */
+          uncon_pcb = pcb;
+        }
+      }
+      /* compare PCB remote addr+port to UDP source addr+port */
+      if ((local_match != 0) &&
+          (pcb->remote_port == src) &&
+          (ip_addr_isany(&pcb->remote_ip) ||
+           ip_addr_cmp(&(pcb->remote_ip), &current_iphdr_src))) {
+        /* the first fully matching PCB */
+        if (prev != NULL) {
+          /* move the pcb to the front of udp_pcbs so that is
+             found faster next time */
+          prev->next = pcb->next;
+          pcb->next = udp_pcbs;
+          udp_pcbs = pcb;
+        } else {
+          UDP_STATS_INC(udp.cachehit);
+        }
+        break;
+      }
+      prev = pcb;
+    }
+    /* no fully matching pcb found? then look for an unconnected pcb */
+    if (pcb == NULL) {
+      pcb = uncon_pcb;
+    }
+  }
+
+  /* Check checksum if this is a match or if it was directed at us. */
+  if (pcb != NULL || ip_addr_cmp(&inp->ip_addr, &current_iphdr_dest)) {
+    LWIP_DEBUGF(UDP_DEBUG | LWIP_DBG_TRACE, ("udp_input: calculating checksum\n"));
+#if LWIP_UDPLITE
+    if (IPH_PROTO(iphdr) == IP_PROTO_UDPLITE) {
+      /* Do the UDP Lite checksum */
+#if CHECKSUM_CHECK_UDP
+      u16_t chklen = ntohs(udphdr->len);
+      if (chklen < sizeof(struct udp_hdr)) {
+        if (chklen == 0) {
+          /* For UDP-Lite, checksum length of 0 means checksum
+             over the complete packet (See RFC 3828 chap. 3.1) */
+          chklen = p->tot_len;
+        } else {
+          /* At least the UDP-Lite header must be covered by the
+             checksum! (Again, see RFC 3828 chap. 3.1) */
+          UDP_STATS_INC(udp.chkerr);
+          UDP_STATS_INC(udp.drop);
+          snmp_inc_udpinerrors();
+          pbuf_free(p);
+          goto end;
+        }
+      }
+      if (inet_chksum_pseudo_partial(p, &current_iphdr_src, &current_iphdr_dest,
+                             IP_PROTO_UDPLITE, p->tot_len, chklen) != 0) {
+       LWIP_DEBUGF(UDP_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
+                   ("udp_input: UDP Lite datagram discarded due to failing checksum\n"));
+        UDP_STATS_INC(udp.chkerr);
+        UDP_STATS_INC(udp.drop);
+        snmp_inc_udpinerrors();
+        pbuf_free(p);
+        goto end;
+      }
+#endif /* CHECKSUM_CHECK_UDP */
+    } else
+#endif /* LWIP_UDPLITE */
+    {
+#if CHECKSUM_CHECK_UDP
+      if (udphdr->chksum != 0) {
+        if (inet_chksum_pseudo(p, ip_current_src_addr(), ip_current_dest_addr(),
+                               IP_PROTO_UDP, p->tot_len) != 0) {
+          LWIP_DEBUGF(UDP_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
+                      ("udp_input: UDP datagram discarded due to failing checksum\n"));
+          UDP_STATS_INC(udp.chkerr);
+          UDP_STATS_INC(udp.drop);
+          snmp_inc_udpinerrors();
+          pbuf_free(p);
+          goto end;
+        }
+      }
+#endif /* CHECKSUM_CHECK_UDP */
+    }
+    if(pbuf_header(p, -UDP_HLEN)) {
+      /* Can we cope with this failing? Just assert for now */
+      LWIP_ASSERT("pbuf_header failed\n", 0);
+      UDP_STATS_INC(udp.drop);
+      snmp_inc_udpinerrors();
+      pbuf_free(p);
+      goto end;
+    }
+    if (pcb != NULL) {
+      snmp_inc_udpindatagrams();
+#if SO_REUSE && SO_REUSE_RXTOALL
+      if ((broadcast || ip_addr_ismulticast(&current_iphdr_dest)) &&
+          ((pcb->so_options & SOF_REUSEADDR) != 0)) {
+        /* pass broadcast- or multicast packets to all multicast pcbs
+           if SOF_REUSEADDR is set on the first match */
+        struct udp_pcb *mpcb;
+        u8_t p_header_changed = 0;
+        for (mpcb = udp_pcbs; mpcb != NULL; mpcb = mpcb->next) {
+          if (mpcb != pcb) {
+            /* compare PCB local addr+port to UDP destination addr+port */
+            if ((mpcb->local_port == dest) &&
+                ((!broadcast && ip_addr_isany(&mpcb->local_ip)) ||
+                 ip_addr_cmp(&(mpcb->local_ip), &current_iphdr_dest) ||
+#if LWIP_IGMP
+                 ip_addr_ismulticast(&current_iphdr_dest) ||
+#endif /* LWIP_IGMP */
+#if IP_SOF_BROADCAST_RECV
+                 (broadcast && (mpcb->so_options & SOF_BROADCAST)))) {
+#else  /* IP_SOF_BROADCAST_RECV */
+                 (broadcast))) {
+#endif /* IP_SOF_BROADCAST_RECV */
+              /* pass a copy of the packet to all local matches */
+              if (mpcb->recv != NULL) {
+                struct pbuf *q;
+                /* for that, move payload to IP header again */
+                if (p_header_changed == 0) {
+                  pbuf_header(p, (s16_t)((IPH_HL(iphdr) * 4) + UDP_HLEN));
+                  p_header_changed = 1;
+                }
+                q = pbuf_alloc(PBUF_RAW, p->tot_len, PBUF_RAM);
+                if (q != NULL) {
+                  err_t err = pbuf_copy(q, p);
+                  if (err == ERR_OK) {
+                    /* move payload to UDP data */
+                    pbuf_header(q, -(s16_t)((IPH_HL(iphdr) * 4) + UDP_HLEN));
+                    mpcb->recv(mpcb->recv_arg, mpcb, q, ip_current_src_addr(), src);
+                  }
+                }
+              }
+            }
+          }
+        }
+        if (p_header_changed) {
+          /* and move payload to UDP data again */
+          pbuf_header(p, -(s16_t)((IPH_HL(iphdr) * 4) + UDP_HLEN));
+        }
+      }
+#endif /* SO_REUSE && SO_REUSE_RXTOALL */
+      /* callback */
+      if (pcb->recv != NULL) {
+        /* now the recv function is responsible for freeing p */
+        pcb->recv(pcb->recv_arg, pcb, p, ip_current_src_addr(), src);
+      } else {
+        /* no recv function registered? then we have to free the pbuf! */
+        pbuf_free(p);
+        goto end;
+      }
+    } else {
+      LWIP_DEBUGF(UDP_DEBUG | LWIP_DBG_TRACE, ("udp_input: not for us.\n"));
+
+#if LWIP_ICMP
+      /* No match was found, send ICMP destination port unreachable unless
+         destination address was broadcast/multicast. */
+      if (!broadcast &&
+          !ip_addr_ismulticast(&current_iphdr_dest)) {
+        /* move payload pointer back to ip header */
+        pbuf_header(p, (IPH_HL(iphdr) * 4) + UDP_HLEN);
+        LWIP_ASSERT("p->payload == iphdr", (p->payload == iphdr));
+        icmp_dest_unreach(p, ICMP_DUR_PORT);
+      }
+#endif /* LWIP_ICMP */
+      UDP_STATS_INC(udp.proterr);
+      UDP_STATS_INC(udp.drop);
+      snmp_inc_udpnoports();
+      pbuf_free(p);
+    }
+  } else {
+    pbuf_free(p);
+  }
+end:
+  PERF_STOP("udp_input");
+}
+
+/**
+ * Send data using UDP.
+ *
+ * @param pcb UDP PCB used to send the data.
+ * @param p chain of pbuf's to be sent.
+ *
+ * The datagram will be sent to the current remote_ip & remote_port
+ * stored in pcb. If the pcb is not bound to a port, it will
+ * automatically be bound to a random port.
+ *
+ * @return lwIP error code.
+ * - ERR_OK. Successful. No error occured.
+ * - ERR_MEM. Out of memory.
+ * - ERR_RTE. Could not find route to destination address.
+ * - More errors could be returned by lower protocol layers.
+ *
+ * @see udp_disconnect() udp_sendto()
+ */
+err_t
+udp_send(struct udp_pcb *pcb, struct pbuf *p)
+{
+  /* send to the packet using remote ip and port stored in the pcb */
+  return udp_sendto(pcb, p, &pcb->remote_ip, pcb->remote_port);
+}
+
+#if LWIP_CHECKSUM_ON_COPY
+/** Same as udp_send() but with checksum
+ */
+err_t
+udp_send_chksum(struct udp_pcb *pcb, struct pbuf *p,
+                u8_t have_chksum, u16_t chksum)
+{
+  /* send to the packet using remote ip and port stored in the pcb */
+  return udp_sendto_chksum(pcb, p, &pcb->remote_ip, pcb->remote_port,
+    have_chksum, chksum);
+}
+#endif /* LWIP_CHECKSUM_ON_COPY */
+
+/**
+ * Send data to a specified address using UDP.
+ *
+ * @param pcb UDP PCB used to send the data.
+ * @param p chain of pbuf's to be sent.
+ * @param dst_ip Destination IP address.
+ * @param dst_port Destination UDP port.
+ *
+ * dst_ip & dst_port are expected to be in the same byte order as in the pcb.
+ *
+ * If the PCB already has a remote address association, it will
+ * be restored after the data is sent.
+ * 
+ * @return lwIP error code (@see udp_send for possible error codes)
+ *
+ * @see udp_disconnect() udp_send()
+ */
+err_t
+udp_sendto(struct udp_pcb *pcb, struct pbuf *p,
+  ip_addr_t *dst_ip, u16_t dst_port)
+{
+#if LWIP_CHECKSUM_ON_COPY
+  return udp_sendto_chksum(pcb, p, dst_ip, dst_port, 0, 0);
+}
+
+/** Same as udp_sendto(), but with checksum */
+err_t
+udp_sendto_chksum(struct udp_pcb *pcb, struct pbuf *p, ip_addr_t *dst_ip,
+                  u16_t dst_port, u8_t have_chksum, u16_t chksum)
+{
+#endif /* LWIP_CHECKSUM_ON_COPY */
+  struct netif *netif;
+
+  LWIP_DEBUGF(UDP_DEBUG | LWIP_DBG_TRACE, ("udp_send\n"));
+
+  /* find the outgoing network interface for this packet */
+#if LWIP_IGMP
+  netif = ip_route((ip_addr_ismulticast(dst_ip))?(&(pcb->multicast_ip)):(dst_ip));
+#else
+  netif = ip_route(dst_ip);
+#endif /* LWIP_IGMP */
+
+  /* no outgoing network interface could be found? */
+  if (netif == NULL) {
+    LWIP_DEBUGF(UDP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("udp_send: No route to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
+      ip4_addr1_16(dst_ip), ip4_addr2_16(dst_ip), ip4_addr3_16(dst_ip), ip4_addr4_16(dst_ip)));
+    UDP_STATS_INC(udp.rterr);
+    return ERR_RTE;
+  }
+#if LWIP_CHECKSUM_ON_COPY
+  return udp_sendto_if_chksum(pcb, p, dst_ip, dst_port, netif, have_chksum, chksum);
+#else /* LWIP_CHECKSUM_ON_COPY */
+  return udp_sendto_if(pcb, p, dst_ip, dst_port, netif);
+#endif /* LWIP_CHECKSUM_ON_COPY */
+}
+
+/**
+ * Send data to a specified address using UDP.
+ * The netif used for sending can be specified.
+ *
+ * This function exists mainly for DHCP, to be able to send UDP packets
+ * on a netif that is still down.
+ *
+ * @param pcb UDP PCB used to send the data.
+ * @param p chain of pbuf's to be sent.
+ * @param dst_ip Destination IP address.
+ * @param dst_port Destination UDP port.
+ * @param netif the netif used for sending.
+ *
+ * dst_ip & dst_port are expected to be in the same byte order as in the pcb.
+ *
+ * @return lwIP error code (@see udp_send for possible error codes)
+ *
+ * @see udp_disconnect() udp_send()
+ */
+err_t
+udp_sendto_if(struct udp_pcb *pcb, struct pbuf *p,
+  ip_addr_t *dst_ip, u16_t dst_port, struct netif *netif)
+{
+#if LWIP_CHECKSUM_ON_COPY
+  return udp_sendto_if_chksum(pcb, p, dst_ip, dst_port, netif, 0, 0);
+}
+
+/** Same as udp_sendto_if(), but with checksum */
+err_t
+udp_sendto_if_chksum(struct udp_pcb *pcb, struct pbuf *p, ip_addr_t *dst_ip,
+                     u16_t dst_port, struct netif *netif, u8_t have_chksum,
+                     u16_t chksum)
+{
+#endif /* LWIP_CHECKSUM_ON_COPY */
+  struct udp_hdr *udphdr;
+  ip_addr_t *src_ip;
+  err_t err;
+  struct pbuf *q; /* q will be sent down the stack */
+
+#if IP_SOF_BROADCAST
+  /* broadcast filter? */
+  if ( ((pcb->so_options & SOF_BROADCAST) == 0) && ip_addr_isbroadcast(dst_ip, netif) ) {
+    LWIP_DEBUGF(UDP_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
+      ("udp_sendto_if: SOF_BROADCAST not enabled on pcb %p\n", (void *)pcb));
+    return ERR_VAL;
+  }
+#endif /* IP_SOF_BROADCAST */
+
+  /* if the PCB is not yet bound to a port, bind it here */
+  if (pcb->local_port == 0) {
+    LWIP_DEBUGF(UDP_DEBUG | LWIP_DBG_TRACE, ("udp_send: not yet bound to a port, binding now\n"));
+    err = udp_bind(pcb, &pcb->local_ip, pcb->local_port);
+    if (err != ERR_OK) {
+      LWIP_DEBUGF(UDP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_SERIOUS, ("udp_send: forced port bind failed\n"));
+      return err;
+    }
+  }
+
+  /* not enough space to add an UDP header to first pbuf in given p chain? */
+  if (pbuf_header(p, UDP_HLEN)) {
+    /* allocate header in a separate new pbuf */
+    q = pbuf_alloc(PBUF_IP, UDP_HLEN, PBUF_RAM);
+    /* new header pbuf could not be allocated? */
+    if (q == NULL) {
+      LWIP_DEBUGF(UDP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_SERIOUS, ("udp_send: could not allocate header\n"));
+      return ERR_MEM;
+    }
+    /* chain header q in front of given pbuf p */
+    pbuf_chain(q, p);
+    /* first pbuf q points to header pbuf */
+    LWIP_DEBUGF(UDP_DEBUG,
+                ("udp_send: added header pbuf %p before given pbuf %p\n", (void *)q, (void *)p));
+  } else {
+    /* adding space for header within p succeeded */
+    /* first pbuf q equals given pbuf */
+    q = p;
+    LWIP_DEBUGF(UDP_DEBUG, ("udp_send: added header in given pbuf %p\n", (void *)p));
+  }
+  LWIP_ASSERT("check that first pbuf can hold struct udp_hdr",
+              (q->len >= sizeof(struct udp_hdr)));
+  /* q now represents the packet to be sent */
+  udphdr = (struct udp_hdr *)q->payload;
+  udphdr->src = htons(pcb->local_port);
+  udphdr->dest = htons(dst_port);
+  /* in UDP, 0 checksum means 'no checksum' */
+  udphdr->chksum = 0x0000; 
+
+  /* Multicast Loop? */
+#if LWIP_IGMP
+  if (ip_addr_ismulticast(dst_ip) && ((pcb->flags & UDP_FLAGS_MULTICAST_LOOP) != 0)) {
+    q->flags |= PBUF_FLAG_MCASTLOOP;
+  }
+#endif /* LWIP_IGMP */
+
+
+  /* PCB local address is IP_ANY_ADDR? */
+  if (ip_addr_isany(&pcb->local_ip)) {
+    /* use outgoing network interface IP address as source address */
+    src_ip = &(netif->ip_addr);
+  } else {
+    /* check if UDP PCB local IP address is correct
+     * this could be an old address if netif->ip_addr has changed */
+    if (!ip_addr_cmp(&(pcb->local_ip), &(netif->ip_addr))) {
+      /* local_ip doesn't match, drop the packet */
+      if (q != p) {
+        /* free the header pbuf */
+        pbuf_free(q);
+        q = NULL;
+        /* p is still referenced by the caller, and will live on */
+      }
+      return ERR_VAL;
+    }
+    /* use UDP PCB local IP address as source address */
+    src_ip = &(pcb->local_ip);
+  }
+
+  LWIP_DEBUGF(UDP_DEBUG, ("udp_send: sending datagram of length %"U16_F"\n", q->tot_len));
+
+#if LWIP_UDPLITE
+  /* UDP Lite protocol? */
+  if (pcb->flags & UDP_FLAGS_UDPLITE) {
+    u16_t chklen, chklen_hdr;
+    LWIP_DEBUGF(UDP_DEBUG, ("udp_send: UDP LITE packet length %"U16_F"\n", q->tot_len));
+    /* set UDP message length in UDP header */
+    chklen_hdr = chklen = pcb->chksum_len_tx;
+    if ((chklen < sizeof(struct udp_hdr)) || (chklen > q->tot_len)) {
+      if (chklen != 0) {
+        LWIP_DEBUGF(UDP_DEBUG, ("udp_send: UDP LITE pcb->chksum_len is illegal: %"U16_F"\n", chklen));
+      }
+      /* For UDP-Lite, checksum length of 0 means checksum
+         over the complete packet. (See RFC 3828 chap. 3.1)
+         At least the UDP-Lite header must be covered by the
+         checksum, therefore, if chksum_len has an illegal
+         value, we generate the checksum over the complete
+         packet to be safe. */
+      chklen_hdr = 0;
+      chklen = q->tot_len;
+    }
+    udphdr->len = htons(chklen_hdr);
+    /* calculate checksum */
+#if CHECKSUM_GEN_UDP
+    udphdr->chksum = inet_chksum_pseudo_partial(q, src_ip, dst_ip,
+      IP_PROTO_UDPLITE, q->tot_len,
+#if !LWIP_CHECKSUM_ON_COPY
+      chklen);
+#else /* !LWIP_CHECKSUM_ON_COPY */
+      (have_chksum ? UDP_HLEN : chklen));
+    if (have_chksum) {
+      u32_t acc;
+      acc = udphdr->chksum + (u16_t)~(chksum);
+      udphdr->chksum = FOLD_U32T(acc);
+    }
+#endif /* !LWIP_CHECKSUM_ON_COPY */
+
+    /* chksum zero must become 0xffff, as zero means 'no checksum' */
+    if (udphdr->chksum == 0x0000) {
+      udphdr->chksum = 0xffff;
+    }
+#endif /* CHECKSUM_GEN_UDP */
+    /* output to IP */
+    LWIP_DEBUGF(UDP_DEBUG, ("udp_send: ip_output_if (,,,,IP_PROTO_UDPLITE,)\n"));
+#if LWIP_NETIF_HWADDRHINT
+    netif->addr_hint = &(pcb->addr_hint);
+#endif /* LWIP_NETIF_HWADDRHINT*/
+    err = ip_output_if(q, src_ip, dst_ip, pcb->ttl, pcb->tos, IP_PROTO_UDPLITE, netif);
+#if LWIP_NETIF_HWADDRHINT
+    netif->addr_hint = NULL;
+#endif /* LWIP_NETIF_HWADDRHINT*/
+  } else
+#endif /* LWIP_UDPLITE */
+  {      /* UDP */
+    LWIP_DEBUGF(UDP_DEBUG, ("udp_send: UDP packet length %"U16_F"\n", q->tot_len));
+    udphdr->len = htons(q->tot_len);
+    /* calculate checksum */
+#if CHECKSUM_GEN_UDP
+    if ((pcb->flags & UDP_FLAGS_NOCHKSUM) == 0) {
+      u16_t udpchksum;
+#if LWIP_CHECKSUM_ON_COPY
+      if (have_chksum) {
+        u32_t acc;
+        udpchksum = inet_chksum_pseudo_partial(q, src_ip, dst_ip, IP_PROTO_UDP,
+          q->tot_len, UDP_HLEN);
+        acc = udpchksum + (u16_t)~(chksum);
+        udpchksum = FOLD_U32T(acc);
+      } else
+#endif /* LWIP_CHECKSUM_ON_COPY */
+      {
+        udpchksum = inet_chksum_pseudo(q, src_ip, dst_ip, IP_PROTO_UDP, q->tot_len);
+      }
+
+      /* chksum zero must become 0xffff, as zero means 'no checksum' */
+      if (udpchksum == 0x0000) {
+        udpchksum = 0xffff;
+      }
+      udphdr->chksum = udpchksum;
+    }
+#endif /* CHECKSUM_GEN_UDP */
+    LWIP_DEBUGF(UDP_DEBUG, ("udp_send: UDP checksum 0x%04"X16_F"\n", udphdr->chksum));
+    LWIP_DEBUGF(UDP_DEBUG, ("udp_send: ip_output_if (,,,,IP_PROTO_UDP,)\n"));
+    /* output to IP */
+#if LWIP_NETIF_HWADDRHINT
+    netif->addr_hint = &(pcb->addr_hint);
+#endif /* LWIP_NETIF_HWADDRHINT*/
+    err = ip_output_if(q, src_ip, dst_ip, pcb->ttl, pcb->tos, IP_PROTO_UDP, netif);
+#if LWIP_NETIF_HWADDRHINT
+    netif->addr_hint = NULL;
+#endif /* LWIP_NETIF_HWADDRHINT*/
+  }
+  /* TODO: must this be increased even if error occured? */
+  snmp_inc_udpoutdatagrams();
+
+  /* did we chain a separate header pbuf earlier? */
+  if (q != p) {
+    /* free the header pbuf */
+    pbuf_free(q);
+    q = NULL;
+    /* p is still referenced by the caller, and will live on */
+  }
+
+  UDP_STATS_INC(udp.xmit);
+  return err;
+}
+
+/**
+ * Bind an UDP PCB.
+ *
+ * @param pcb UDP PCB to be bound with a local address ipaddr and port.
+ * @param ipaddr local IP address to bind with. Use IP_ADDR_ANY to
+ * bind to all local interfaces.
+ * @param port local UDP port to bind with. Use 0 to automatically bind
+ * to a random port between UDP_LOCAL_PORT_RANGE_START and
+ * UDP_LOCAL_PORT_RANGE_END.
+ *
+ * ipaddr & port are expected to be in the same byte order as in the pcb.
+ *
+ * @return lwIP error code.
+ * - ERR_OK. Successful. No error occured.
+ * - ERR_USE. The specified ipaddr and port are already bound to by
+ * another UDP PCB.
+ *
+ * @see udp_disconnect()
+ */
+err_t
+udp_bind(struct udp_pcb *pcb, ip_addr_t *ipaddr, u16_t port)
+{
+  struct udp_pcb *ipcb;
+  u8_t rebind;
+
+  LWIP_DEBUGF(UDP_DEBUG | LWIP_DBG_TRACE, ("udp_bind(ipaddr = "));
+  ip_addr_debug_print(UDP_DEBUG, ipaddr);
+  LWIP_DEBUGF(UDP_DEBUG | LWIP_DBG_TRACE, (", port = %"U16_F")\n", port));
+
+  rebind = 0;
+  /* Check for double bind and rebind of the same pcb */
+  for (ipcb = udp_pcbs; ipcb != NULL; ipcb = ipcb->next) {
+    /* is this UDP PCB already on active list? */
+    if (pcb == ipcb) {
+      /* pcb may occur at most once in active list */
+      LWIP_ASSERT("rebind == 0", rebind == 0);
+      /* pcb already in list, just rebind */
+      rebind = 1;
+    }
+
+    /* By default, we don't allow to bind to a port that any other udp
+       PCB is alread bound to, unless *all* PCBs with that port have tha
+       REUSEADDR flag set. */
+#if SO_REUSE
+    else if (((pcb->so_options & SOF_REUSEADDR) == 0) &&
+             ((ipcb->so_options & SOF_REUSEADDR) == 0)) {
+#else /* SO_REUSE */
+    /* port matches that of PCB in list and REUSEADDR not set -> reject */
+    else {
+#endif /* SO_REUSE */
+      if ((ipcb->local_port == port) &&
+          /* IP address matches, or one is IP_ADDR_ANY? */
+          (ip_addr_isany(&(ipcb->local_ip)) ||
+           ip_addr_isany(ipaddr) ||
+           ip_addr_cmp(&(ipcb->local_ip), ipaddr))) {
+        /* other PCB already binds to this local IP and port */
+        LWIP_DEBUGF(UDP_DEBUG,
+                    ("udp_bind: local port %"U16_F" already bound by another pcb\n", port));
+        return ERR_USE;
+      }
+    }
+  }
+
+  ip_addr_set(&pcb->local_ip, ipaddr);
+
+  /* no port specified? */
+  if (port == 0) {
+#ifndef UDP_LOCAL_PORT_RANGE_START
+#define UDP_LOCAL_PORT_RANGE_START 4096
+#define UDP_LOCAL_PORT_RANGE_END   0x7fff
+#endif
+    port = UDP_LOCAL_PORT_RANGE_START;
+    ipcb = udp_pcbs;
+    while ((ipcb != NULL) && (port != UDP_LOCAL_PORT_RANGE_END)) {
+      if (ipcb->local_port == port) {
+        /* port is already used by another udp_pcb */
+        port++;
+        /* restart scanning all udp pcbs */
+        ipcb = udp_pcbs;
+      } else {
+        /* go on with next udp pcb */
+        ipcb = ipcb->next;
+      }
+    }
+    if (ipcb != NULL) {
+      /* no more ports available in local range */
+      LWIP_DEBUGF(UDP_DEBUG, ("udp_bind: out of free UDP ports\n"));
+      return ERR_USE;
+    }
+  }
+  pcb->local_port = port;
+  snmp_insert_udpidx_tree(pcb);
+  /* pcb not active yet? */
+  if (rebind == 0) {
+    /* place the PCB on the active list if not already there */
+    pcb->next = udp_pcbs;
+    udp_pcbs = pcb;
+  }
+  LWIP_DEBUGF(UDP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE,
+              ("udp_bind: bound to %"U16_F".%"U16_F".%"U16_F".%"U16_F", port %"U16_F"\n",
+               ip4_addr1_16(&pcb->local_ip), ip4_addr2_16(&pcb->local_ip),
+               ip4_addr3_16(&pcb->local_ip), ip4_addr4_16(&pcb->local_ip),
+               pcb->local_port));
+  return ERR_OK;
+}
+/**
+ * Connect an UDP PCB.
+ *
+ * This will associate the UDP PCB with the remote address.
+ *
+ * @param pcb UDP PCB to be connected with remote address ipaddr and port.
+ * @param ipaddr remote IP address to connect with.
+ * @param port remote UDP port to connect with.
+ *
+ * @return lwIP error code
+ *
+ * ipaddr & port are expected to be in the same byte order as in the pcb.
+ *
+ * The udp pcb is bound to a random local port if not already bound.
+ *
+ * @see udp_disconnect()
+ */
+err_t
+udp_connect(struct udp_pcb *pcb, ip_addr_t *ipaddr, u16_t port)
+{
+  struct udp_pcb *ipcb;
+
+  if (pcb->local_port == 0) {
+    err_t err = udp_bind(pcb, &pcb->local_ip, pcb->local_port);
+    if (err != ERR_OK) {
+      return err;
+    }
+  }
+
+  ip_addr_set(&pcb->remote_ip, ipaddr);
+  pcb->remote_port = port;
+  pcb->flags |= UDP_FLAGS_CONNECTED;
+/** TODO: this functionality belongs in upper layers */
+#ifdef LWIP_UDP_TODO
+  /* Nail down local IP for netconn_addr()/getsockname() */
+  if (ip_addr_isany(&pcb->local_ip) && !ip_addr_isany(&pcb->remote_ip)) {
+    struct netif *netif;
+
+    if ((netif = ip_route(&(pcb->remote_ip))) == NULL) {
+      LWIP_DEBUGF(UDP_DEBUG, ("udp_connect: No route to 0x%lx\n", pcb->remote_ip.addr));
+      UDP_STATS_INC(udp.rterr);
+      return ERR_RTE;
+    }
+    /** TODO: this will bind the udp pcb locally, to the interface which
+        is used to route output packets to the remote address. However, we
+        might want to accept incoming packets on any interface! */
+    pcb->local_ip = netif->ip_addr;
+  } else if (ip_addr_isany(&pcb->remote_ip)) {
+    pcb->local_ip.addr = 0;
+  }
+#endif
+  LWIP_DEBUGF(UDP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE,
+              ("udp_connect: connected to %"U16_F".%"U16_F".%"U16_F".%"U16_F",port %"U16_F"\n",
+               ip4_addr1_16(&pcb->local_ip), ip4_addr2_16(&pcb->local_ip),
+               ip4_addr3_16(&pcb->local_ip), ip4_addr4_16(&pcb->local_ip),
+               pcb->local_port));
+
+  /* Insert UDP PCB into the list of active UDP PCBs. */
+  for (ipcb = udp_pcbs; ipcb != NULL; ipcb = ipcb->next) {
+    if (pcb == ipcb) {
+      /* already on the list, just return */
+      return ERR_OK;
+    }
+  }
+  /* PCB not yet on the list, add PCB now */
+  pcb->next = udp_pcbs;
+  udp_pcbs = pcb;
+  return ERR_OK;
+}
+
+/**
+ * Disconnect a UDP PCB
+ *
+ * @param pcb the udp pcb to disconnect.
+ */
+void
+udp_disconnect(struct udp_pcb *pcb)
+{
+  /* reset remote address association */
+  ip_addr_set_any(&pcb->remote_ip);
+  pcb->remote_port = 0;
+  /* mark PCB as unconnected */
+  pcb->flags &= ~UDP_FLAGS_CONNECTED;
+}
+
+/**
+ * Set a receive callback for a UDP PCB
+ *
+ * This callback will be called when receiving a datagram for the pcb.
+ *
+ * @param pcb the pcb for wich to set the recv callback
+ * @param recv function pointer of the callback function
+ * @param recv_arg additional argument to pass to the callback function
+ */
+void
+udp_recv(struct udp_pcb *pcb, udp_recv_fn recv, void *recv_arg)
+{
+  /* remember recv() callback and user data */
+  pcb->recv = recv;
+  pcb->recv_arg = recv_arg;
+}
+
+/**
+ * Remove an UDP PCB.
+ *
+ * @param pcb UDP PCB to be removed. The PCB is removed from the list of
+ * UDP PCB's and the data structure is freed from memory.
+ *
+ * @see udp_new()
+ */
+void
+udp_remove(struct udp_pcb *pcb)
+{
+  struct udp_pcb *pcb2;
+
+  snmp_delete_udpidx_tree(pcb);
+  /* pcb to be removed is first in list? */
+  if (udp_pcbs == pcb) {
+    /* make list start at 2nd pcb */
+    udp_pcbs = udp_pcbs->next;
+    /* pcb not 1st in list */
+  } else {
+    for (pcb2 = udp_pcbs; pcb2 != NULL; pcb2 = pcb2->next) {
+      /* find pcb in udp_pcbs list */
+      if (pcb2->next != NULL && pcb2->next == pcb) {
+        /* remove pcb from list */
+        pcb2->next = pcb->next;
+      }
+    }
+  }
+  memp_free(MEMP_UDP_PCB, pcb);
+}
+
+/**
+ * Create a UDP PCB.
+ *
+ * @return The UDP PCB which was created. NULL if the PCB data structure
+ * could not be allocated.
+ *
+ * @see udp_remove()
+ */
+struct udp_pcb *
+udp_new(void)
+{
+  struct udp_pcb *pcb;
+  pcb = (struct udp_pcb *)memp_malloc(MEMP_UDP_PCB);
+  /* could allocate UDP PCB? */
+  if (pcb != NULL) {
+    /* UDP Lite: by initializing to all zeroes, chksum_len is set to 0
+     * which means checksum is generated over the whole datagram per default
+     * (recommended as default by RFC 3828). */
+    /* initialize PCB to all zeroes */
+    memset(pcb, 0, sizeof(struct udp_pcb));
+    pcb->ttl = UDP_TTL;
+  }
+  return pcb;
+}
+
+#if UDP_DEBUG
+/**
+ * Print UDP header information for debug purposes.
+ *
+ * @param udphdr pointer to the udp header in memory.
+ */
+void
+udp_debug_print(struct udp_hdr *udphdr)
+{
+  LWIP_DEBUGF(UDP_DEBUG, ("UDP header:\n"));
+  LWIP_DEBUGF(UDP_DEBUG, ("+-------------------------------+\n"));
+  LWIP_DEBUGF(UDP_DEBUG, ("|     %5"U16_F"     |     %5"U16_F"     | (src port, dest port)\n",
+                          ntohs(udphdr->src), ntohs(udphdr->dest)));
+  LWIP_DEBUGF(UDP_DEBUG, ("+-------------------------------+\n"));
+  LWIP_DEBUGF(UDP_DEBUG, ("|     %5"U16_F"     |     0x%04"X16_F"    | (len, chksum)\n",
+                          ntohs(udphdr->len), ntohs(udphdr->chksum)));
+  LWIP_DEBUGF(UDP_DEBUG, ("+-------------------------------+\n"));
+}
+#endif /* UDP_DEBUG */
+
+#endif /* LWIP_UDP */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/include/ipv4/lwip/autoip.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,119 @@
+/**
+ * @file
+ *
+ * AutoIP Automatic LinkLocal IP Configuration
+ */
+
+/*
+ *
+ * Copyright (c) 2007 Dominik Spies <kontakt@dspies.de>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * Author: Dominik Spies <kontakt@dspies.de>
+ *
+ * This is a AutoIP implementation for the lwIP TCP/IP stack. It aims to conform
+ * with RFC 3927.
+ *
+ *
+ * Please coordinate changes and requests with Dominik Spies
+ * <kontakt@dspies.de>
+ */
+ 
+#ifndef __LWIP_AUTOIP_H__
+#define __LWIP_AUTOIP_H__
+
+#include "lwip/opt.h"
+
+#if LWIP_AUTOIP /* don't build if not configured for use in lwipopts.h */
+
+#include "lwip/netif.h"
+#include "lwip/udp.h"
+#include "netif/etharp.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* AutoIP Timing */
+#define AUTOIP_TMR_INTERVAL      100
+#define AUTOIP_TICKS_PER_SECOND (1000 / AUTOIP_TMR_INTERVAL)
+
+/* RFC 3927 Constants */
+#define PROBE_WAIT               1   /* second   (initial random delay)                 */
+#define PROBE_MIN                1   /* second   (minimum delay till repeated probe)    */
+#define PROBE_MAX                2   /* seconds  (maximum delay till repeated probe)    */
+#define PROBE_NUM                3   /*          (number of probe packets)              */
+#define ANNOUNCE_NUM             2   /*          (number of announcement packets)       */
+#define ANNOUNCE_INTERVAL        2   /* seconds  (time between announcement packets)    */
+#define ANNOUNCE_WAIT            2   /* seconds  (delay before announcing)              */
+#define MAX_CONFLICTS            10  /*          (max conflicts before rate limiting)   */
+#define RATE_LIMIT_INTERVAL      60  /* seconds  (delay between successive attempts)    */
+#define DEFEND_INTERVAL          10  /* seconds  (min. wait between defensive ARPs)     */
+
+/* AutoIP client states */
+#define AUTOIP_STATE_OFF         0
+#define AUTOIP_STATE_PROBING     1
+#define AUTOIP_STATE_ANNOUNCING  2
+#define AUTOIP_STATE_BOUND       3
+
+struct autoip
+{
+  ip_addr_t llipaddr;       /* the currently selected, probed, announced or used LL IP-Address */
+  u8_t state;               /* current AutoIP state machine state */
+  u8_t sent_num;            /* sent number of probes or announces, dependent on state */
+  u16_t ttw;                /* ticks to wait, tick is AUTOIP_TMR_INTERVAL long */
+  u8_t lastconflict;        /* ticks until a conflict can be solved by defending */
+  u8_t tried_llipaddr;      /* total number of probed/used Link Local IP-Addresses */
+};
+
+
+/** Init srand, has to be called before entering mainloop */
+void autoip_init(void);
+
+/** Set a struct autoip allocated by the application to work with */
+void autoip_set_struct(struct netif *netif, struct autoip *autoip);
+
+/** Start AutoIP client */
+err_t autoip_start(struct netif *netif);
+
+/** Stop AutoIP client */
+err_t autoip_stop(struct netif *netif);
+
+/** Handles every incoming ARP Packet, called by etharp_arp_input */
+void autoip_arp_reply(struct netif *netif, struct etharp_hdr *hdr);
+
+/** Has to be called in loop every AUTOIP_TMR_INTERVAL milliseconds */
+void autoip_tmr(void);
+
+/** Handle a possible change in the network configuration */
+void autoip_network_changed(struct netif *netif);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* LWIP_AUTOIP */
+
+#endif /* __LWIP_AUTOIP_H__ */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/include/ipv4/lwip/icmp.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,111 @@
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+#ifndef __LWIP_ICMP_H__
+#define __LWIP_ICMP_H__
+
+#include "lwip/opt.h"
+#include "lwip/pbuf.h"
+#include "lwip/ip_addr.h"
+#include "lwip/netif.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#define ICMP_ER 0      /* echo reply */
+#define ICMP_DUR 3     /* destination unreachable */
+#define ICMP_SQ 4      /* source quench */
+#define ICMP_RD 5      /* redirect */
+#define ICMP_ECHO 8    /* echo */
+#define ICMP_TE 11     /* time exceeded */
+#define ICMP_PP 12     /* parameter problem */
+#define ICMP_TS 13     /* timestamp */
+#define ICMP_TSR 14    /* timestamp reply */
+#define ICMP_IRQ 15    /* information request */
+#define ICMP_IR 16     /* information reply */
+
+enum icmp_dur_type {
+  ICMP_DUR_NET = 0,    /* net unreachable */
+  ICMP_DUR_HOST = 1,   /* host unreachable */
+  ICMP_DUR_PROTO = 2,  /* protocol unreachable */
+  ICMP_DUR_PORT = 3,   /* port unreachable */
+  ICMP_DUR_FRAG = 4,   /* fragmentation needed and DF set */
+  ICMP_DUR_SR = 5      /* source route failed */
+};
+
+enum icmp_te_type {
+  ICMP_TE_TTL = 0,     /* time to live exceeded in transit */
+  ICMP_TE_FRAG = 1     /* fragment reassembly time exceeded */
+};
+
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/bpstruct.h"
+#endif
+/*  This is the standard ICMP header only that the u32_t data
+ *  is splitted to two u16_t like ICMP echo needs it.
+ *  This header is also used for other ICMP types that do not
+ *  use the data part.
+ */
+PACK_STRUCT_BEGIN
+struct icmp_echo_hdr {
+  PACK_STRUCT_FIELD(u8_t type);
+  PACK_STRUCT_FIELD(u8_t code);
+  PACK_STRUCT_FIELD(u16_t chksum);
+  PACK_STRUCT_FIELD(u16_t id);
+  PACK_STRUCT_FIELD(u16_t seqno);
+} PACK_STRUCT_STRUCT;
+PACK_STRUCT_END
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/epstruct.h"
+#endif
+
+#define ICMPH_TYPE(hdr) ((hdr)->type)
+#define ICMPH_CODE(hdr) ((hdr)->code)
+
+/*  Combines type and code to an u16_t */
+#define ICMPH_TYPE_SET(hdr, t) ((hdr)->type = (t))
+#define ICMPH_CODE_SET(hdr, c) ((hdr)->code = (c))
+
+
+#if LWIP_ICMP /* don't build if not configured for use in lwipopts.h */
+
+void icmp_input(struct pbuf *p, struct netif *inp);
+void icmp_dest_unreach(struct pbuf *p, enum icmp_dur_type t);
+void icmp_time_exceeded(struct pbuf *p, enum icmp_te_type t);
+
+#endif /* LWIP_ICMP */
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __LWIP_ICMP_H__ */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/include/ipv4/lwip/igmp.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,106 @@
+/*
+ * Copyright (c) 2002 CITEL Technologies Ltd.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without 
+ * modification, are permitted provided that the following conditions 
+ * are met: 
+ * 1. Redistributions of source code must retain the above copyright 
+ *    notice, this list of conditions and the following disclaimer. 
+ * 2. Redistributions in binary form must reproduce the above copyright 
+ *    notice, this list of conditions and the following disclaimer in the 
+ *    documentation and/or other materials provided with the distribution. 
+ * 3. Neither the name of CITEL Technologies Ltd nor the names of its contributors 
+ *    may be used to endorse or promote products derived from this software 
+ *    without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY CITEL TECHNOLOGIES AND CONTRIBUTORS ``AS IS''
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
+ * ARE DISCLAIMED.  IN NO EVENT SHALL CITEL TECHNOLOGIES OR CONTRIBUTORS BE LIABLE 
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 
+ * SUCH DAMAGE. 
+ *
+ * This file is a contribution to the lwIP TCP/IP stack.
+ * The Swedish Institute of Computer Science and Adam Dunkels
+ * are specifically granted permission to redistribute this
+ * source code.
+*/
+
+#ifndef __LWIP_IGMP_H__
+#define __LWIP_IGMP_H__
+
+#include "lwip/opt.h"
+#include "lwip/ip_addr.h"
+#include "lwip/netif.h"
+#include "lwip/pbuf.h"
+
+#if LWIP_IGMP /* don't build if not configured for use in lwipopts.h */
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+
+/* IGMP timer */
+#define IGMP_TMR_INTERVAL              100 /* Milliseconds */
+#define IGMP_V1_DELAYING_MEMBER_TMR   (1000/IGMP_TMR_INTERVAL)
+#define IGMP_JOIN_DELAYING_MEMBER_TMR (500 /IGMP_TMR_INTERVAL)
+
+/* MAC Filter Actions, these are passed to a netif's
+ * igmp_mac_filter callback function. */
+#define IGMP_DEL_MAC_FILTER            0
+#define IGMP_ADD_MAC_FILTER            1
+
+
+/**
+ * igmp group structure - there is
+ * a list of groups for each interface
+ * these should really be linked from the interface, but
+ * if we keep them separate we will not affect the lwip original code
+ * too much
+ * 
+ * There will be a group for the all systems group address but this 
+ * will not run the state machine as it is used to kick off reports
+ * from all the other groups
+ */
+struct igmp_group {
+  /** next link */
+  struct igmp_group *next;
+  /** interface on which the group is active */
+  struct netif      *netif;
+  /** multicast address */
+  ip_addr_t          group_address;
+  /** signifies we were the last person to report */
+  u8_t               last_reporter_flag;
+  /** current state of the group */
+  u8_t               group_state;
+  /** timer for reporting, negative is OFF */
+  u16_t              timer;
+  /** counter of simultaneous uses */
+  u8_t               use;
+};
+
+/*  Prototypes */
+void   igmp_init(void);
+err_t  igmp_start(struct netif *netif);
+err_t  igmp_stop(struct netif *netif);
+void   igmp_report_groups(struct netif *netif);
+struct igmp_group *igmp_lookfor_group(struct netif *ifp, ip_addr_t *addr);
+void   igmp_input(struct pbuf *p, struct netif *inp, ip_addr_t *dest);
+err_t  igmp_joingroup(ip_addr_t *ifaddr, ip_addr_t *groupaddr);
+err_t  igmp_leavegroup(ip_addr_t *ifaddr, ip_addr_t *groupaddr);
+void   igmp_tmr(void);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* LWIP_IGMP */
+
+#endif /* __LWIP_IGMP_H__ */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/include/ipv4/lwip/inet.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,107 @@
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+#ifndef __LWIP_INET_H__
+#define __LWIP_INET_H__
+
+#include "lwip/opt.h"
+#include "lwip/def.h"
+#include "lwip/ip_addr.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/*  For compatibility with BSD code */
+struct in_addr {
+  u32_t s_addr;
+};
+
+/** 255.255.255.255 */
+#define INADDR_NONE         IPADDR_NONE
+/** 127.0.0.1 */
+#define INADDR_LOOPBACK     IPADDR_LOOPBACK
+/** 0.0.0.0 */
+#define INADDR_ANY          IPADDR_ANY
+/** 255.255.255.255 */
+#define INADDR_BROADCAST    IPADDR_BROADCAST
+
+/* Definitions of the bits in an Internet address integer.
+
+   On subnets, host and network parts are found according to
+   the subnet mask, not these masks.  */
+#define IN_CLASSA(a)        IP_CLASSA(a)
+#define IN_CLASSA_NET       IP_CLASSA_NET
+#define IN_CLASSA_NSHIFT    IP_CLASSA_NSHIFT
+#define IN_CLASSA_HOST      IP_CLASSA_HOST
+#define IN_CLASSA_MAX       IP_CLASSA_MAX
+
+#define IN_CLASSB(b)        IP_CLASSB(b)
+#define IN_CLASSB_NET       IP_CLASSB_NET
+#define IN_CLASSB_NSHIFT    IP_CLASSB_NSHIFT
+#define IN_CLASSB_HOST      IP_CLASSB_HOST
+#define IN_CLASSB_MAX       IP_CLASSB_MAX
+
+#define IN_CLASSC(c)        IP_CLASSC(c)
+#define IN_CLASSC_NET       IP_CLASSC_NET
+#define IN_CLASSC_NSHIFT    IP_CLASSC_NSHIFT
+#define IN_CLASSC_HOST      IP_CLASSC_HOST
+#define IN_CLASSC_MAX       IP_CLASSC_MAX
+
+#define IN_CLASSD(d)        IP_CLASSD(d)
+#define IN_CLASSD_NET       IP_CLASSD_NET     /* These ones aren't really */
+#define IN_CLASSD_NSHIFT    IP_CLASSD_NSHIFT  /*   net and host fields, but */
+#define IN_CLASSD_HOST      IP_CLASSD_HOST    /*   routing needn't know. */
+#define IN_CLASSD_MAX       IP_CLASSD_MAX
+
+#define IN_MULTICAST(a)     IP_MULTICAST(a)
+
+#define IN_EXPERIMENTAL(a)  IP_EXPERIMENTAL(a)
+#define IN_BADCLASS(a)      IP_BADCLASS(a)
+
+#define IN_LOOPBACKNET      IP_LOOPBACKNET
+
+#define inet_addr_from_ipaddr(target_inaddr, source_ipaddr) ((target_inaddr)->s_addr = ip4_addr_get_u32(source_ipaddr))
+#define inet_addr_to_ipaddr(target_ipaddr, source_inaddr)   (ip4_addr_set_u32(target_ipaddr, (source_inaddr)->s_addr))
+/* ATTENTION: the next define only works because both s_addr and ip_addr_t are an u32_t effectively! */
+#define inet_addr_to_ipaddr_p(target_ipaddr_p, source_inaddr)   ((target_ipaddr_p) = (ip_addr_t*)&((source_inaddr)->s_addr))
+
+/* directly map this to the lwip internal functions */
+#define inet_addr(cp)         ipaddr_addr(cp)
+#define inet_aton(cp, addr)   ipaddr_aton(cp, (ip_addr_t*)addr)
+#define inet_ntoa(addr)       ipaddr_ntoa((ip_addr_t*)&(addr))
+#define inet_ntoa_r(addr, buf, buflen) ipaddr_ntoa_r((ip_addr_t*)&(addr), buf, buflen)
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __LWIP_INET_H__ */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/include/ipv4/lwip/inet_chksum.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,90 @@
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+#ifndef __LWIP_INET_CHKSUM_H__
+#define __LWIP_INET_CHKSUM_H__
+
+#include "lwip/opt.h"
+
+#include "lwip/pbuf.h"
+#include "lwip/ip_addr.h"
+
+/** Swap the bytes in an u16_t: much like htons() for little-endian */
+#ifndef SWAP_BYTES_IN_WORD
+#if LWIP_PLATFORM_BYTESWAP && (BYTE_ORDER == LITTLE_ENDIAN)
+/* little endian and PLATFORM_BYTESWAP defined */
+#define SWAP_BYTES_IN_WORD(w) LWIP_PLATFORM_HTONS(w)
+#else /* LWIP_PLATFORM_BYTESWAP && (BYTE_ORDER == LITTLE_ENDIAN) */
+/* can't use htons on big endian (or PLATFORM_BYTESWAP not defined)... */
+#define SWAP_BYTES_IN_WORD(w) (((w) & 0xff) << 8) | (((w) & 0xff00) >> 8)
+#endif /* LWIP_PLATFORM_BYTESWAP && (BYTE_ORDER == LITTLE_ENDIAN)*/
+#endif /* SWAP_BYTES_IN_WORD */
+
+/** Split an u32_t in two u16_ts and add them up */
+#ifndef FOLD_U32T
+#define FOLD_U32T(u)          (((u) >> 16) + ((u) & 0x0000ffffUL))
+#endif
+
+#if LWIP_CHECKSUM_ON_COPY
+/** Function-like macro: same as MEMCPY but returns the checksum of copied data
+    as u16_t */
+#ifndef LWIP_CHKSUM_COPY
+#define LWIP_CHKSUM_COPY(dst, src, len) lwip_chksum_copy(dst, src, len)
+#ifndef LWIP_CHKSUM_COPY_ALGORITHM
+#define LWIP_CHKSUM_COPY_ALGORITHM 1
+#endif /* LWIP_CHKSUM_COPY_ALGORITHM */
+#endif /* LWIP_CHKSUM_COPY */
+#else /* LWIP_CHECKSUM_ON_COPY */
+#define LWIP_CHKSUM_COPY_ALGORITHM 0
+#endif /* LWIP_CHECKSUM_ON_COPY */
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+u16_t inet_chksum(void *dataptr, u16_t len);
+u16_t inet_chksum_pbuf(struct pbuf *p);
+u16_t inet_chksum_pseudo(struct pbuf *p,
+       ip_addr_t *src, ip_addr_t *dest,
+       u8_t proto, u16_t proto_len);
+u16_t inet_chksum_pseudo_partial(struct pbuf *p,
+       ip_addr_t *src, ip_addr_t *dest,
+       u8_t proto, u16_t proto_len, u16_t chksum_len);
+#if LWIP_CHKSUM_COPY_ALGORITHM
+u16_t lwip_chksum_copy(void *dst, const void *src, u16_t len);
+#endif /* LWIP_CHKSUM_COPY_ALGORITHM */
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __LWIP_INET_H__ */
+
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/include/ipv4/lwip/ip.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,213 @@
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+#ifndef __LWIP_IP_H__
+#define __LWIP_IP_H__
+
+#include "lwip/opt.h"
+
+#include "lwip/def.h"
+#include "lwip/pbuf.h"
+#include "lwip/ip_addr.h"
+#include "lwip/err.h"
+#include "lwip/netif.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/** Currently, the function ip_output_if_opt() is only used with IGMP */
+#define IP_OPTIONS_SEND   LWIP_IGMP
+
+#define IP_HLEN 20
+
+#define IP_PROTO_ICMP    1
+#define IP_PROTO_IGMP    2
+#define IP_PROTO_UDP     17
+#define IP_PROTO_UDPLITE 136
+#define IP_PROTO_TCP     6
+
+/* This is passed as the destination address to ip_output_if (not
+   to ip_output), meaning that an IP header already is constructed
+   in the pbuf. This is used when TCP retransmits. */
+#ifdef IP_HDRINCL
+#undef IP_HDRINCL
+#endif /* IP_HDRINCL */
+#define IP_HDRINCL  NULL
+
+#if LWIP_NETIF_HWADDRHINT
+#define IP_PCB_ADDRHINT ;u8_t addr_hint
+#else
+#define IP_PCB_ADDRHINT
+#endif /* LWIP_NETIF_HWADDRHINT */
+
+/* This is the common part of all PCB types. It needs to be at the
+   beginning of a PCB type definition. It is located here so that
+   changes to this common part are made in one location instead of
+   having to change all PCB structs. */
+#define IP_PCB \
+  /* ip addresses in network byte order */ \
+  ip_addr_t local_ip; \
+  ip_addr_t remote_ip; \
+   /* Socket options */  \
+  u8_t so_options;      \
+   /* Type Of Service */ \
+  u8_t tos;              \
+  /* Time To Live */     \
+  u8_t ttl               \
+  /* link layer address resolution hint */ \
+  IP_PCB_ADDRHINT
+
+struct ip_pcb {
+/* Common members of all PCB types */
+  IP_PCB;
+};
+
+/*
+ * Option flags per-socket. These are the same like SO_XXX.
+ */
+/*#define SOF_DEBUG       (u8_t)0x01U     Unimplemented: turn on debugging info recording */
+#define SOF_ACCEPTCONN    (u8_t)0x02U  /* socket has had listen() */
+#define SOF_REUSEADDR     (u8_t)0x04U  /* allow local address reuse */
+#define SOF_KEEPALIVE     (u8_t)0x08U  /* keep connections alive */
+/*#define SOF_DONTROUTE   (u8_t)0x10U     Unimplemented: just use interface addresses */
+#define SOF_BROADCAST     (u8_t)0x20U  /* permit to send and to receive broadcast messages (see IP_SOF_BROADCAST option) */
+/*#define SOF_USELOOPBACK (u8_t)0x40U     Unimplemented: bypass hardware when possible */
+#define SOF_LINGER        (u8_t)0x80U  /* linger on close if data present */
+/*#define SOF_OOBINLINE   (u16_t)0x0100U     Unimplemented: leave received OOB data in line */
+/*#define SOF_REUSEPORT   (u16_t)0x0200U     Unimplemented: allow local address & port reuse */
+
+/* These flags are inherited (e.g. from a listen-pcb to a connection-pcb): */
+#define SOF_INHERITED   (SOF_REUSEADDR|SOF_KEEPALIVE|SOF_LINGER/*|SOF_DEBUG|SOF_DONTROUTE|SOF_OOBINLINE*/)
+
+
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/bpstruct.h"
+#endif
+PACK_STRUCT_BEGIN
+struct ip_hdr {
+  /* version / header length / type of service */
+  PACK_STRUCT_FIELD(u16_t _v_hl_tos);
+  /* total length */
+  PACK_STRUCT_FIELD(u16_t _len);
+  /* identification */
+  PACK_STRUCT_FIELD(u16_t _id);
+  /* fragment offset field */
+  PACK_STRUCT_FIELD(u16_t _offset);
+#define IP_RF 0x8000        /* reserved fragment flag */
+#define IP_DF 0x4000        /* dont fragment flag */
+#define IP_MF 0x2000        /* more fragments flag */
+#define IP_OFFMASK 0x1fff   /* mask for fragmenting bits */
+  /* time to live */
+  PACK_STRUCT_FIELD(u8_t _ttl);
+  /* protocol*/
+  PACK_STRUCT_FIELD(u8_t _proto);
+  /* checksum */
+  PACK_STRUCT_FIELD(u16_t _chksum);
+  /* source and destination IP addresses */
+  PACK_STRUCT_FIELD(ip_addr_p_t src);
+  PACK_STRUCT_FIELD(ip_addr_p_t dest); 
+} PACK_STRUCT_STRUCT;
+PACK_STRUCT_END
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/epstruct.h"
+#endif
+
+#define IPH_V(hdr)  (ntohs((hdr)->_v_hl_tos) >> 12)
+#define IPH_HL(hdr) ((ntohs((hdr)->_v_hl_tos) >> 8) & 0x0f)
+#define IPH_TOS(hdr) (ntohs((hdr)->_v_hl_tos) & 0xff)
+#define IPH_LEN(hdr) ((hdr)->_len)
+#define IPH_ID(hdr) ((hdr)->_id)
+#define IPH_OFFSET(hdr) ((hdr)->_offset)
+#define IPH_TTL(hdr) ((hdr)->_ttl)
+#define IPH_PROTO(hdr) ((hdr)->_proto)
+#define IPH_CHKSUM(hdr) ((hdr)->_chksum)
+
+#define IPH_VHLTOS_SET(hdr, v, hl, tos) (hdr)->_v_hl_tos = (htons(((v) << 12) | ((hl) << 8) | (tos)))
+#define IPH_LEN_SET(hdr, len) (hdr)->_len = (len)
+#define IPH_ID_SET(hdr, id) (hdr)->_id = (id)
+#define IPH_OFFSET_SET(hdr, off) (hdr)->_offset = (off)
+#define IPH_TTL_SET(hdr, ttl) (hdr)->_ttl = (u8_t)(ttl)
+#define IPH_PROTO_SET(hdr, proto) (hdr)->_proto = (u8_t)(proto)
+#define IPH_CHKSUM_SET(hdr, chksum) (hdr)->_chksum = (chksum)
+
+/** The interface that provided the packet for the current callback invocation. */
+extern struct netif *current_netif;
+/** Header of the input packet currently being processed. */
+extern const struct ip_hdr *current_header;
+/** Source IP address of current_header */
+extern ip_addr_t current_iphdr_src;
+/** Destination IP address of current_header */
+extern ip_addr_t current_iphdr_dest;
+
+#define ip_init() /* Compatibility define, not init needed. */
+struct netif *ip_route(ip_addr_t *dest);
+err_t ip_input(struct pbuf *p, struct netif *inp);
+err_t ip_output(struct pbuf *p, ip_addr_t *src, ip_addr_t *dest,
+       u8_t ttl, u8_t tos, u8_t proto);
+err_t ip_output_if(struct pbuf *p, ip_addr_t *src, ip_addr_t *dest,
+       u8_t ttl, u8_t tos, u8_t proto,
+       struct netif *netif);
+#if LWIP_NETIF_HWADDRHINT
+err_t ip_output_hinted(struct pbuf *p, ip_addr_t *src, ip_addr_t *dest,
+       u8_t ttl, u8_t tos, u8_t proto, u8_t *addr_hint);
+#endif /* LWIP_NETIF_HWADDRHINT */
+#if IP_OPTIONS_SEND
+err_t ip_output_if_opt(struct pbuf *p, ip_addr_t *src, ip_addr_t *dest,
+       u8_t ttl, u8_t tos, u8_t proto, struct netif *netif, void *ip_options,
+       u16_t optlen);
+#endif /* IP_OPTIONS_SEND */
+/** Get the interface that received the current packet.
+ * This function must only be called from a receive callback (udp_recv,
+ * raw_recv, tcp_accept). It will return NULL otherwise. */
+#define ip_current_netif()  (current_netif)
+/** Get the IP header of the current packet.
+ * This function must only be called from a receive callback (udp_recv,
+ * raw_recv, tcp_accept). It will return NULL otherwise. */
+#define ip_current_header() (current_header)
+/** Source IP address of current_header */
+#define ip_current_src_addr()  (&current_iphdr_src)
+/** Destination IP address of current_header */
+#define ip_current_dest_addr() (&current_iphdr_dest)
+
+#if IP_DEBUG
+void ip_debug_print(struct pbuf *p);
+#else
+#define ip_debug_print(p)
+#endif /* IP_DEBUG */
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __LWIP_IP_H__ */
+
+
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/include/ipv4/lwip/ip_addr.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,244 @@
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ *
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+#ifndef __LWIP_IP_ADDR_H__
+#define __LWIP_IP_ADDR_H__
+
+#include "lwip/opt.h"
+#include "lwip/def.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* This is the aligned version of ip_addr_t,
+   used as local variable, on the stack, etc. */
+struct ip_addr {
+  u32_t addr;
+};
+
+/* This is the packed version of ip_addr_t,
+   used in network headers that are itself packed */
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/bpstruct.h"
+#endif
+PACK_STRUCT_BEGIN
+struct ip_addr_packed {
+  PACK_STRUCT_FIELD(u32_t addr);
+} PACK_STRUCT_STRUCT;
+PACK_STRUCT_END
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/epstruct.h"
+#endif
+
+/** ip_addr_t uses a struct for convenience only, so that the same defines can
+ * operate both on ip_addr_t as well as on ip_addr_p_t. */
+typedef struct ip_addr ip_addr_t;
+typedef struct ip_addr_packed ip_addr_p_t;
+
+/*
+ * struct ipaddr2 is used in the definition of the ARP packet format in
+ * order to support compilers that don't have structure packing.
+ */
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/bpstruct.h"
+#endif
+PACK_STRUCT_BEGIN
+struct ip_addr2 {
+  PACK_STRUCT_FIELD(u16_t addrw[2]);
+} PACK_STRUCT_STRUCT;
+PACK_STRUCT_END
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/epstruct.h"
+#endif
+
+/* Forward declaration to not include netif.h */
+struct netif;
+
+extern const ip_addr_t ip_addr_any;
+extern const ip_addr_t ip_addr_broadcast;
+
+/** IP_ADDR_ can be used as a fixed IP address
+ *  for the wildcard and the broadcast address
+ */
+#define IP_ADDR_ANY         ((ip_addr_t *)&ip_addr_any)
+#define IP_ADDR_BROADCAST   ((ip_addr_t *)&ip_addr_broadcast)
+
+/** 255.255.255.255 */
+#define IPADDR_NONE         ((u32_t)0xffffffffUL)
+/** 127.0.0.1 */
+#define IPADDR_LOOPBACK     ((u32_t)0x7f000001UL)
+/** 0.0.0.0 */
+#define IPADDR_ANY          ((u32_t)0x00000000UL)
+/** 255.255.255.255 */
+#define IPADDR_BROADCAST    ((u32_t)0xffffffffUL)
+
+/* Definitions of the bits in an Internet address integer.
+
+   On subnets, host and network parts are found according to
+   the subnet mask, not these masks.  */
+#define IP_CLASSA(a)        ((((u32_t)(a)) & 0x80000000UL) == 0)
+#define IP_CLASSA_NET       0xff000000
+#define IP_CLASSA_NSHIFT    24
+#define IP_CLASSA_HOST      (0xffffffff & ~IP_CLASSA_NET)
+#define IP_CLASSA_MAX       128
+
+#define IP_CLASSB(a)        ((((u32_t)(a)) & 0xc0000000UL) == 0x80000000UL)
+#define IP_CLASSB_NET       0xffff0000
+#define IP_CLASSB_NSHIFT    16
+#define IP_CLASSB_HOST      (0xffffffff & ~IP_CLASSB_NET)
+#define IP_CLASSB_MAX       65536
+
+#define IP_CLASSC(a)        ((((u32_t)(a)) & 0xe0000000UL) == 0xc0000000UL)
+#define IP_CLASSC_NET       0xffffff00
+#define IP_CLASSC_NSHIFT    8
+#define IP_CLASSC_HOST      (0xffffffff & ~IP_CLASSC_NET)
+
+#define IP_CLASSD(a)        (((u32_t)(a) & 0xf0000000UL) == 0xe0000000UL)
+#define IP_CLASSD_NET       0xf0000000          /* These ones aren't really */
+#define IP_CLASSD_NSHIFT    28                  /*   net and host fields, but */
+#define IP_CLASSD_HOST      0x0fffffff          /*   routing needn't know. */
+#define IP_MULTICAST(a)     IP_CLASSD(a)
+
+#define IP_EXPERIMENTAL(a)  (((u32_t)(a) & 0xf0000000UL) == 0xf0000000UL)
+#define IP_BADCLASS(a)      (((u32_t)(a) & 0xf0000000UL) == 0xf0000000UL)
+
+#define IP_LOOPBACKNET      127                 /* official! */
+
+
+#if BYTE_ORDER == BIG_ENDIAN
+/** Set an IP address given by the four byte-parts */
+#define IP4_ADDR(ipaddr, a,b,c,d) \
+        (ipaddr)->addr = ((u32_t)((a) & 0xff) << 24) | \
+                         ((u32_t)((b) & 0xff) << 16) | \
+                         ((u32_t)((c) & 0xff) << 8)  | \
+                          (u32_t)((d) & 0xff)
+#else
+/** Set an IP address given by the four byte-parts.
+    Little-endian version that prevents the use of htonl. */
+#define IP4_ADDR(ipaddr, a,b,c,d) \
+        (ipaddr)->addr = ((u32_t)((d) & 0xff) << 24) | \
+                         ((u32_t)((c) & 0xff) << 16) | \
+                         ((u32_t)((b) & 0xff) << 8)  | \
+                          (u32_t)((a) & 0xff)
+#endif
+
+/** MEMCPY-like copying of IP addresses where addresses are known to be
+ * 16-bit-aligned if the port is correctly configured (so a port could define
+ * this to copying 2 u16_t's) - no NULL-pointer-checking needed. */
+#ifndef IPADDR2_COPY
+#define IPADDR2_COPY(dest, src) SMEMCPY(dest, src, sizeof(ip_addr_t))
+#endif
+
+/** Copy IP address - faster than ip_addr_set: no NULL check */
+#define ip_addr_copy(dest, src) ((dest).addr = (src).addr)
+/** Safely copy one IP address to another (src may be NULL) */
+#define ip_addr_set(dest, src) ((dest)->addr = \
+                                    ((src) == NULL ? 0 : \
+                                    (src)->addr))
+/** Set complete address to zero */
+#define ip_addr_set_zero(ipaddr)      ((ipaddr)->addr = 0)
+/** Set address to IPADDR_ANY (no need for htonl()) */
+#define ip_addr_set_any(ipaddr)       ((ipaddr)->addr = IPADDR_ANY)
+/** Set address to loopback address */
+#define ip_addr_set_loopback(ipaddr)  ((ipaddr)->addr = PP_HTONL(IPADDR_LOOPBACK))
+/** Safely copy one IP address to another and change byte order
+ * from host- to network-order. */
+#define ip_addr_set_hton(dest, src) ((dest)->addr = \
+                               ((src) == NULL ? 0:\
+                               htonl((src)->addr)))
+/** IPv4 only: set the IP address given as an u32_t */
+#define ip4_addr_set_u32(dest_ipaddr, src_u32) ((dest_ipaddr)->addr = (src_u32))
+/** IPv4 only: get the IP address as an u32_t */
+#define ip4_addr_get_u32(src_ipaddr) ((src_ipaddr)->addr)
+
+/** Get the network address by combining host address with netmask */
+#define ip_addr_get_network(target, host, netmask) ((target)->addr = ((host)->addr) & ((netmask)->addr))
+
+/**
+ * Determine if two address are on the same network.
+ *
+ * @arg addr1 IP address 1
+ * @arg addr2 IP address 2
+ * @arg mask network identifier mask
+ * @return !0 if the network identifiers of both address match
+ */
+#define ip_addr_netcmp(addr1, addr2, mask) (((addr1)->addr & \
+                                              (mask)->addr) == \
+                                             ((addr2)->addr & \
+                                              (mask)->addr))
+#define ip_addr_cmp(addr1, addr2) ((addr1)->addr == (addr2)->addr)
+
+#define ip_addr_isany(addr1) ((addr1) == NULL || (addr1)->addr == IPADDR_ANY)
+
+#define ip_addr_isbroadcast(ipaddr, netif) ip4_addr_isbroadcast((ipaddr)->addr, (netif))
+u8_t ip4_addr_isbroadcast(u32_t addr, const struct netif *netif);
+
+#define ip_addr_netmask_valid(netmask) ip4_addr_netmask_valid((netmask)->addr)
+u8_t ip4_addr_netmask_valid(u32_t netmask);
+
+#define ip_addr_ismulticast(addr1) (((addr1)->addr & PP_HTONL(0xf0000000UL)) == PP_HTONL(0xe0000000UL))
+
+#define ip_addr_islinklocal(addr1) (((addr1)->addr & PP_HTONL(0xffff0000UL)) == PP_HTONL(0xa9fe0000UL))
+
+#define ip_addr_debug_print(debug, ipaddr) \
+  LWIP_DEBUGF(debug, ("%"U16_F".%"U16_F".%"U16_F".%"U16_F,             \
+                      ipaddr != NULL ? ip4_addr1_16(ipaddr) : 0,       \
+                      ipaddr != NULL ? ip4_addr2_16(ipaddr) : 0,       \
+                      ipaddr != NULL ? ip4_addr3_16(ipaddr) : 0,       \
+                      ipaddr != NULL ? ip4_addr4_16(ipaddr) : 0))
+
+/* Get one byte from the 4-byte address */
+#define ip4_addr1(ipaddr) (((u8_t*)(ipaddr))[0])
+#define ip4_addr2(ipaddr) (((u8_t*)(ipaddr))[1])
+#define ip4_addr3(ipaddr) (((u8_t*)(ipaddr))[2])
+#define ip4_addr4(ipaddr) (((u8_t*)(ipaddr))[3])
+/* These are cast to u16_t, with the intent that they are often arguments
+ * to printf using the U16_F format from cc.h. */
+#define ip4_addr1_16(ipaddr) ((u16_t)ip4_addr1(ipaddr))
+#define ip4_addr2_16(ipaddr) ((u16_t)ip4_addr2(ipaddr))
+#define ip4_addr3_16(ipaddr) ((u16_t)ip4_addr3(ipaddr))
+#define ip4_addr4_16(ipaddr) ((u16_t)ip4_addr4(ipaddr))
+
+/** For backwards compatibility */
+#define ip_ntoa(ipaddr)  ipaddr_ntoa(ipaddr)
+
+u32_t ipaddr_addr(const char *cp);
+int ipaddr_aton(const char *cp, ip_addr_t *addr);
+/** returns ptr to static buffer; not reentrant! */
+char *ipaddr_ntoa(const ip_addr_t *addr);
+char *ipaddr_ntoa_r(const ip_addr_t *addr, char *buf, int buflen);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __LWIP_IP_ADDR_H__ */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/include/ipv4/lwip/ip_frag.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,88 @@
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Jani Monoses <jani@iv.ro>
+ *
+ */
+
+#ifndef __LWIP_IP_FRAG_H__
+#define __LWIP_IP_FRAG_H__
+
+#include "lwip/opt.h"
+#include "lwip/err.h"
+#include "lwip/pbuf.h"
+#include "lwip/netif.h"
+#include "lwip/ip_addr.h"
+#include "lwip/ip.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#if IP_REASSEMBLY
+/* The IP reassembly timer interval in milliseconds. */
+#define IP_TMR_INTERVAL 1000
+
+/* IP reassembly helper struct.
+ * This is exported because memp needs to know the size.
+ */
+struct ip_reassdata {
+  struct ip_reassdata *next;
+  struct pbuf *p;
+  struct ip_hdr iphdr;
+  u16_t datagram_len;
+  u8_t flags;
+  u8_t timer;
+};
+
+void ip_reass_init(void);
+void ip_reass_tmr(void);
+struct pbuf * ip_reass(struct pbuf *p);
+#endif /* IP_REASSEMBLY */
+
+#if IP_FRAG
+#if !IP_FRAG_USES_STATIC_BUF && !LWIP_NETIF_TX_SINGLE_PBUF
+/** A custom pbuf that holds a reference to another pbuf, which is freed
+ * when this custom pbuf is freed. This is used to create a custom PBUF_REF
+ * that points into the original pbuf. */
+struct pbuf_custom_ref {
+  /** 'base class' */
+  struct pbuf_custom pc;
+  /** pointer to the original pbuf that is referenced */
+  struct pbuf *original;
+};
+#endif /* !IP_FRAG_USES_STATIC_BUF && !LWIP_NETIF_TX_SINGLE_PBUF */
+
+err_t ip_frag(struct pbuf *p, struct netif *netif, ip_addr_t *dest);
+#endif /* IP_FRAG */
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __LWIP_IP_FRAG_H__ */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/include/lwip/api.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,285 @@
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+#ifndef __LWIP_API_H__
+#define __LWIP_API_H__
+
+#include "lwip/opt.h"
+
+#if LWIP_NETCONN /* don't build if not configured for use in lwipopts.h */
+
+#include <stddef.h> /* for size_t */
+
+#include "lwip/netbuf.h"
+#include "lwip/sys.h"
+#include "lwip/ip_addr.h"
+#include "lwip/err.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* Throughout this file, IP addresses and port numbers are expected to be in
+ * the same byte order as in the corresponding pcb.
+ */
+
+/* Flags for netconn_write (u8_t) */
+#define NETCONN_NOFLAG    0x00
+#define NETCONN_NOCOPY    0x00 /* Only for source code compatibility */
+#define NETCONN_COPY      0x01
+#define NETCONN_MORE      0x02
+#define NETCONN_DONTBLOCK 0x04
+
+/* Flags for struct netconn.flags (u8_t) */
+/** TCP: when data passed to netconn_write doesn't fit into the send buffer,
+    this temporarily stores whether to wake up the original application task
+    if data couldn't be sent in the first try. */
+#define NETCONN_FLAG_WRITE_DELAYED            0x01
+/** Should this netconn avoid blocking? */
+#define NETCONN_FLAG_NON_BLOCKING             0x02
+/** Was the last connect action a non-blocking one? */
+#define NETCONN_FLAG_IN_NONBLOCKING_CONNECT   0x04
+/** If this is set, a TCP netconn must call netconn_recved() to update
+    the TCP receive window (done automatically if not set). */
+#define NETCONN_FLAG_NO_AUTO_RECVED           0x08
+/** If a nonblocking write has been rejected before, poll_tcp needs to
+    check if the netconn is writable again */
+#define NETCONN_FLAG_CHECK_WRITESPACE         0x10
+
+
+/* Helpers to process several netconn_types by the same code */
+#define NETCONNTYPE_GROUP(t)    (t&0xF0)
+#define NETCONNTYPE_DATAGRAM(t) (t&0xE0)
+
+/** Protocol family and type of the netconn */
+enum netconn_type {
+  NETCONN_INVALID    = 0,
+  /* NETCONN_TCP Group */
+  NETCONN_TCP        = 0x10,
+  /* NETCONN_UDP Group */
+  NETCONN_UDP        = 0x20,
+  NETCONN_UDPLITE    = 0x21,
+  NETCONN_UDPNOCHKSUM= 0x22,
+  /* NETCONN_RAW Group */
+  NETCONN_RAW        = 0x40
+};
+
+/** Current state of the netconn. Non-TCP netconns are always
+ * in state NETCONN_NONE! */
+enum netconn_state {
+  NETCONN_NONE,
+  NETCONN_WRITE,
+  NETCONN_LISTEN,
+  NETCONN_CONNECT,
+  NETCONN_CLOSE
+};
+
+/** Use to inform the callback function about changes */
+enum netconn_evt {
+  NETCONN_EVT_RCVPLUS,
+  NETCONN_EVT_RCVMINUS,
+  NETCONN_EVT_SENDPLUS,
+  NETCONN_EVT_SENDMINUS,
+  NETCONN_EVT_ERROR
+};
+
+#if LWIP_IGMP
+/** Used for netconn_join_leave_group() */
+enum netconn_igmp {
+  NETCONN_JOIN,
+  NETCONN_LEAVE
+};
+#endif /* LWIP_IGMP */
+
+/* forward-declare some structs to avoid to include their headers */
+struct ip_pcb;
+struct tcp_pcb;
+struct udp_pcb;
+struct raw_pcb;
+struct netconn;
+struct api_msg_msg;
+
+/** A callback prototype to inform about events for a netconn */
+typedef void (* netconn_callback)(struct netconn *, enum netconn_evt, u16_t len);
+
+/** A netconn descriptor */
+struct netconn {
+  /** type of the netconn (TCP, UDP or RAW) */
+  enum netconn_type type;
+  /** current state of the netconn */
+  enum netconn_state state;
+  /** the lwIP internal protocol control block */
+  union {
+    struct ip_pcb  *ip;
+    struct tcp_pcb *tcp;
+    struct udp_pcb *udp;
+    struct raw_pcb *raw;
+  } pcb;
+  /** the last error this netconn had */
+  err_t last_err;
+  /** sem that is used to synchroneously execute functions in the core context */
+  sys_sem_t op_completed;
+  /** mbox where received packets are stored until they are fetched
+      by the netconn application thread (can grow quite big) */
+  sys_mbox_t recvmbox;
+#if LWIP_TCP
+  /** mbox where new connections are stored until processed
+      by the application thread */
+  sys_mbox_t acceptmbox;
+#endif /* LWIP_TCP */
+  /** only used for socket layer */
+#if LWIP_SOCKET
+  int socket;
+#endif /* LWIP_SOCKET */
+#if LWIP_SO_RCVTIMEO
+  /** timeout to wait for new data to be received
+      (or connections to arrive for listening netconns) */
+  int recv_timeout;
+#endif /* LWIP_SO_RCVTIMEO */
+#if LWIP_SO_RCVBUF
+  /** maximum amount of bytes queued in recvmbox
+      not used for TCP: adjust TCP_WND instead! */
+  int recv_bufsize;
+#endif /* LWIP_SO_RCVBUF */
+  /** number of bytes currently in recvmbox to be received,
+      tested against recv_bufsize to limit bytes on recvmbox
+      for UDP and RAW
+      @todo: should only be necessary with LWIP_SO_RCVBUF==1 */
+  s16_t recv_avail;
+  /** flags holding more netconn-internal state, see NETCONN_FLAG_* defines */
+  u8_t flags;
+#if LWIP_TCP
+  /** TCP: when data passed to netconn_write doesn't fit into the send buffer,
+      this temporarily stores how much is already sent. */
+  size_t write_offset;
+  /** TCP: when data passed to netconn_write doesn't fit into the send buffer,
+      this temporarily stores the message.
+      Also used during connect and close. */
+  struct api_msg_msg *current_msg;
+#endif /* LWIP_TCP */
+  /** A callback function that is informed about events for this netconn */
+  netconn_callback callback;
+};
+
+/** Register an Network connection event */
+#define API_EVENT(c,e,l) if (c->callback) {         \
+                           (*c->callback)(c, e, l); \
+                         }
+
+/** Set conn->last_err to err but don't overwrite fatal errors */
+#define NETCONN_SET_SAFE_ERR(conn, err) do { \
+  SYS_ARCH_DECL_PROTECT(lev); \
+  SYS_ARCH_PROTECT(lev); \
+  if (!ERR_IS_FATAL((conn)->last_err)) { \
+    (conn)->last_err = err; \
+  } \
+  SYS_ARCH_UNPROTECT(lev); \
+} while(0);
+
+/* Network connection functions: */
+#define netconn_new(t)                  netconn_new_with_proto_and_callback(t, 0, NULL)
+#define netconn_new_with_callback(t, c) netconn_new_with_proto_and_callback(t, 0, c)
+struct
+netconn *netconn_new_with_proto_and_callback(enum netconn_type t, u8_t proto,
+                                             netconn_callback callback);
+err_t   netconn_delete(struct netconn *conn);
+/** Get the type of a netconn (as enum netconn_type). */
+#define netconn_type(conn) (conn->type)
+
+err_t   netconn_getaddr(struct netconn *conn, ip_addr_t *addr,
+                        u16_t *port, u8_t local);
+#define netconn_peer(c,i,p) netconn_getaddr(c,i,p,0)
+#define netconn_addr(c,i,p) netconn_getaddr(c,i,p,1)
+
+err_t   netconn_bind(struct netconn *conn, ip_addr_t *addr, u16_t port);
+err_t   netconn_connect(struct netconn *conn, ip_addr_t *addr, u16_t port);
+err_t   netconn_disconnect (struct netconn *conn);
+err_t   netconn_listen_with_backlog(struct netconn *conn, u8_t backlog);
+#define netconn_listen(conn) netconn_listen_with_backlog(conn, TCP_DEFAULT_LISTEN_BACKLOG)
+err_t   netconn_accept(struct netconn *conn, struct netconn **new_conn);
+err_t   netconn_recv(struct netconn *conn, struct netbuf **new_buf);
+err_t   netconn_recv_tcp_pbuf(struct netconn *conn, struct pbuf **new_buf);
+void    netconn_recved(struct netconn *conn, u32_t length);
+err_t   netconn_sendto(struct netconn *conn, struct netbuf *buf,
+                       ip_addr_t *addr, u16_t port);
+err_t   netconn_send(struct netconn *conn, struct netbuf *buf);
+err_t   netconn_write(struct netconn *conn, const void *dataptr, size_t size,
+                      u8_t apiflags);
+err_t   netconn_close(struct netconn *conn);
+err_t   netconn_shutdown(struct netconn *conn, u8_t shut_rx, u8_t shut_tx);
+
+#if LWIP_IGMP
+err_t   netconn_join_leave_group(struct netconn *conn, ip_addr_t *multiaddr,
+                                 ip_addr_t *netif_addr, enum netconn_igmp join_or_leave);
+#endif /* LWIP_IGMP */
+#if LWIP_DNS
+err_t   netconn_gethostbyname(const char *name, ip_addr_t *addr);
+#endif /* LWIP_DNS */
+
+#define netconn_err(conn)               ((conn)->last_err)
+#define netconn_recv_bufsize(conn)      ((conn)->recv_bufsize)
+
+/** Set the blocking status of netconn calls (@todo: write/send is missing) */
+#define netconn_set_nonblocking(conn, val)  do { if(val) { \
+  (conn)->flags |= NETCONN_FLAG_NON_BLOCKING; \
+} else { \
+  (conn)->flags &= ~ NETCONN_FLAG_NON_BLOCKING; }} while(0)
+/** Get the blocking status of netconn calls (@todo: write/send is missing) */
+#define netconn_is_nonblocking(conn)        (((conn)->flags & NETCONN_FLAG_NON_BLOCKING) != 0)
+
+/** TCP: Set the no-auto-recved status of netconn calls (see NETCONN_FLAG_NO_AUTO_RECVED) */
+#define netconn_set_noautorecved(conn, val)  do { if(val) { \
+  (conn)->flags |= NETCONN_FLAG_NO_AUTO_RECVED; \
+} else { \
+  (conn)->flags &= ~ NETCONN_FLAG_NO_AUTO_RECVED; }} while(0)
+/** TCP: Get the no-auto-recved status of netconn calls (see NETCONN_FLAG_NO_AUTO_RECVED) */
+#define netconn_get_noautorecved(conn)        (((conn)->flags & NETCONN_FLAG_NO_AUTO_RECVED) != 0)
+
+#if LWIP_SO_RCVTIMEO
+/** Set the receive timeout in milliseconds */
+#define netconn_set_recvtimeout(conn, timeout)      ((conn)->recv_timeout = (timeout))
+/** Get the receive timeout in milliseconds */
+#define netconn_get_recvtimeout(conn)               ((conn)->recv_timeout)
+#endif /* LWIP_SO_RCVTIMEO */
+#if LWIP_SO_RCVBUF
+/** Set the receive buffer in bytes */
+#define netconn_set_recvbufsize(conn, recvbufsize)  ((conn)->recv_bufsize = (recvbufsize))
+/** Get the receive buffer in bytes */
+#define netconn_get_recvbufsize(conn)               ((conn)->recv_bufsize)
+#endif /* LWIP_SO_RCVBUF*/
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* LWIP_NETCONN */
+
+#endif /* __LWIP_API_H__ */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/include/lwip/api_msg.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,173 @@
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+#ifndef __LWIP_API_MSG_H__
+#define __LWIP_API_MSG_H__
+
+#include "lwip/opt.h"
+
+#if LWIP_NETCONN /* don't build if not configured for use in lwipopts.h */
+
+#include <stddef.h> /* for size_t */
+
+#include "lwip/ip_addr.h"
+#include "lwip/err.h"
+#include "lwip/sys.h"
+#include "lwip/igmp.h"
+#include "lwip/api.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#define NETCONN_SHUT_RD   1
+#define NETCONN_SHUT_WR   2
+#define NETCONN_SHUT_RDWR 3
+
+/* IP addresses and port numbers are expected to be in
+ * the same byte order as in the corresponding pcb.
+ */
+/** This struct includes everything that is necessary to execute a function
+    for a netconn in another thread context (mainly used to process netconns
+    in the tcpip_thread context to be thread safe). */
+struct api_msg_msg {
+  /** The netconn which to process - always needed: it includes the semaphore
+      which is used to block the application thread until the function finished. */
+  struct netconn *conn;
+  /** The return value of the function executed in tcpip_thread. */
+  err_t err;
+  /** Depending on the executed function, one of these union members is used */
+  union {
+    /** used for do_send */
+    struct netbuf *b;
+    /** used for do_newconn */
+    struct {
+      u8_t proto;
+    } n;
+    /** used for do_bind and do_connect */
+    struct {
+      ip_addr_t *ipaddr;
+      u16_t port;
+    } bc;
+    /** used for do_getaddr */
+    struct {
+      ip_addr_t *ipaddr;
+      u16_t *port;
+      u8_t local;
+    } ad;
+    /** used for do_write */
+    struct {
+      const void *dataptr;
+      size_t len;
+      u8_t apiflags;
+    } w;
+    /** used for do_recv */
+    struct {
+      u32_t len;
+    } r;
+    /** used for do_close (/shutdown) */
+    struct {
+      u8_t shut;
+    } sd;
+#if LWIP_IGMP
+    /** used for do_join_leave_group */
+    struct {
+      ip_addr_t *multiaddr;
+      ip_addr_t *netif_addr;
+      enum netconn_igmp join_or_leave;
+    } jl;
+#endif /* LWIP_IGMP */
+#if TCP_LISTEN_BACKLOG
+    struct {
+      u8_t backlog;
+    } lb;
+#endif /* TCP_LISTEN_BACKLOG */
+  } msg;
+};
+
+/** This struct contains a function to execute in another thread context and
+    a struct api_msg_msg that serves as an argument for this function.
+    This is passed to tcpip_apimsg to execute functions in tcpip_thread context. */
+struct api_msg {
+  /** function to execute in tcpip_thread context */
+  void (* function)(struct api_msg_msg *msg);
+  /** arguments for this function */
+  struct api_msg_msg msg;
+};
+
+#if LWIP_DNS
+/** As do_gethostbyname requires more arguments but doesn't require a netconn,
+    it has its own struct (to avoid struct api_msg getting bigger than necessary).
+    do_gethostbyname must be called using tcpip_callback instead of tcpip_apimsg
+    (see netconn_gethostbyname). */
+struct dns_api_msg {
+  /** Hostname to query or dotted IP address string */
+  const char *name;
+  /** Rhe resolved address is stored here */
+  ip_addr_t *addr;
+  /** This semaphore is posted when the name is resolved, the application thread
+      should wait on it. */
+  sys_sem_t *sem;
+  /** Errors are given back here */
+  err_t *err;
+};
+#endif /* LWIP_DNS */
+
+void do_newconn         ( struct api_msg_msg *msg);
+void do_delconn         ( struct api_msg_msg *msg);
+void do_bind            ( struct api_msg_msg *msg);
+void do_connect         ( struct api_msg_msg *msg);
+void do_disconnect      ( struct api_msg_msg *msg);
+void do_listen          ( struct api_msg_msg *msg);
+void do_send            ( struct api_msg_msg *msg);
+void do_recv            ( struct api_msg_msg *msg);
+void do_write           ( struct api_msg_msg *msg);
+void do_getaddr         ( struct api_msg_msg *msg);
+void do_close           ( struct api_msg_msg *msg);
+void do_shutdown        ( struct api_msg_msg *msg);
+#if LWIP_IGMP
+void do_join_leave_group( struct api_msg_msg *msg);
+#endif /* LWIP_IGMP */
+
+#if LWIP_DNS
+void do_gethostbyname(void *arg);
+#endif /* LWIP_DNS */
+
+struct netconn* netconn_alloc(enum netconn_type t, netconn_callback callback);
+void netconn_free(struct netconn *conn);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* LWIP_NETCONN */
+
+#endif /* __LWIP_API_MSG_H__ */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/include/lwip/arch.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,238 @@
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+#ifndef __LWIP_ARCH_H__
+#define __LWIP_ARCH_H__
+
+#ifndef LITTLE_ENDIAN
+#define LITTLE_ENDIAN 1234
+#endif
+
+#ifndef BIG_ENDIAN
+#define BIG_ENDIAN 4321
+#endif
+
+#include "arch/cc.h"
+
+/** Temporary: define format string for size_t if not defined in cc.h */
+#ifndef SZT_F
+#define SZT_F U32_F
+#endif /* SZT_F */
+/** Temporary upgrade helper: define format string for u8_t as hex if not
+    defined in cc.h */
+#ifndef X8_F
+#define X8_F  "02x"
+#endif /* X8_F */
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#ifndef PACK_STRUCT_BEGIN
+#define PACK_STRUCT_BEGIN
+#endif /* PACK_STRUCT_BEGIN */
+
+#ifndef PACK_STRUCT_END
+#define PACK_STRUCT_END
+#endif /* PACK_STRUCT_END */
+
+#ifndef PACK_STRUCT_FIELD
+#define PACK_STRUCT_FIELD(x) x
+#endif /* PACK_STRUCT_FIELD */
+
+
+#ifndef LWIP_UNUSED_ARG
+#define LWIP_UNUSED_ARG(x) (void)x
+#endif /* LWIP_UNUSED_ARG */ 
+
+
+#ifdef LWIP_PROVIDE_ERRNO
+
+#define  EPERM         1  /* Operation not permitted */
+#define  ENOENT        2  /* No such file or directory */
+#define  ESRCH         3  /* No such process */
+#define  EINTR         4  /* Interrupted system call */
+#define  EIO           5  /* I/O error */
+#define  ENXIO         6  /* No such device or address */
+#define  E2BIG         7  /* Arg list too long */
+#define  ENOEXEC       8  /* Exec format error */
+#define  EBADF         9  /* Bad file number */
+#define  ECHILD       10  /* No child processes */
+#define  EAGAIN       11  /* Try again */
+#define  ENOMEM       12  /* Out of memory */
+#define  EACCES       13  /* Permission denied */
+#define  EFAULT       14  /* Bad address */
+#define  ENOTBLK      15  /* Block device required */
+#define  EBUSY        16  /* Device or resource busy */
+#define  EEXIST       17  /* File exists */
+#define  EXDEV        18  /* Cross-device link */
+#define  ENODEV       19  /* No such device */
+#define  ENOTDIR      20  /* Not a directory */
+#define  EISDIR       21  /* Is a directory */
+#define  EINVAL       22  /* Invalid argument */
+#define  ENFILE       23  /* File table overflow */
+#define  EMFILE       24  /* Too many open files */
+#define  ENOTTY       25  /* Not a typewriter */
+#define  ETXTBSY      26  /* Text file busy */
+#define  EFBIG        27  /* File too large */
+#define  ENOSPC       28  /* No space left on device */
+#define  ESPIPE       29  /* Illegal seek */
+#define  EROFS        30  /* Read-only file system */
+#define  EMLINK       31  /* Too many links */
+#define  EPIPE        32  /* Broken pipe */
+#define  EDOM         33  /* Math argument out of domain of func */
+#define  ERANGE       34  /* Math result not representable */
+#define  EDEADLK      35  /* Resource deadlock would occur */
+#define  ENAMETOOLONG 36  /* File name too long */
+#define  ENOLCK       37  /* No record locks available */
+#define  ENOSYS       38  /* Function not implemented */
+#define  ENOTEMPTY    39  /* Directory not empty */
+#define  ELOOP        40  /* Too many symbolic links encountered */
+#define  EWOULDBLOCK  EAGAIN  /* Operation would block */
+#define  ENOMSG       42  /* No message of desired type */
+#define  EIDRM        43  /* Identifier removed */
+#define  ECHRNG       44  /* Channel number out of range */
+#define  EL2NSYNC     45  /* Level 2 not synchronized */
+#define  EL3HLT       46  /* Level 3 halted */
+#define  EL3RST       47  /* Level 3 reset */
+#define  ELNRNG       48  /* Link number out of range */
+#define  EUNATCH      49  /* Protocol driver not attached */
+#define  ENOCSI       50  /* No CSI structure available */
+#define  EL2HLT       51  /* Level 2 halted */
+#define  EBADE        52  /* Invalid exchange */
+#define  EBADR        53  /* Invalid request descriptor */
+#define  EXFULL       54  /* Exchange full */
+#define  ENOANO       55  /* No anode */
+#define  EBADRQC      56  /* Invalid request code */
+#define  EBADSLT      57  /* Invalid slot */
+
+#define  EDEADLOCK    EDEADLK
+
+#define  EBFONT       59  /* Bad font file format */
+#define  ENOSTR       60  /* Device not a stream */
+#define  ENODATA      61  /* No data available */
+#define  ETIME        62  /* Timer expired */
+#define  ENOSR        63  /* Out of streams resources */
+#define  ENONET       64  /* Machine is not on the network */
+#define  ENOPKG       65  /* Package not installed */
+#define  EREMOTE      66  /* Object is remote */
+#define  ENOLINK      67  /* Link has been severed */
+#define  EADV         68  /* Advertise error */
+#define  ESRMNT       69  /* Srmount error */
+#define  ECOMM        70  /* Communication error on send */
+#define  EPROTO       71  /* Protocol error */
+#define  EMULTIHOP    72  /* Multihop attempted */
+#define  EDOTDOT      73  /* RFS specific error */
+#define  EBADMSG      74  /* Not a data message */
+#define  EOVERFLOW    75  /* Value too large for defined data type */
+#define  ENOTUNIQ     76  /* Name not unique on network */
+#define  EBADFD       77  /* File descriptor in bad state */
+#define  EREMCHG      78  /* Remote address changed */
+#define  ELIBACC      79  /* Can not access a needed shared library */
+#define  ELIBBAD      80  /* Accessing a corrupted shared library */
+#define  ELIBSCN      81  /* .lib section in a.out corrupted */
+#define  ELIBMAX      82  /* Attempting to link in too many shared libraries */
+#define  ELIBEXEC     83  /* Cannot exec a shared library directly */
+#define  EILSEQ       84  /* Illegal byte sequence */
+#define  ERESTART     85  /* Interrupted system call should be restarted */
+#define  ESTRPIPE     86  /* Streams pipe error */
+#define  EUSERS       87  /* Too many users */
+#define  ENOTSOCK     88  /* Socket operation on non-socket */
+#define  EDESTADDRREQ 89  /* Destination address required */
+#define  EMSGSIZE     90  /* Message too long */
+#define  EPROTOTYPE   91  /* Protocol wrong type for socket */
+#define  ENOPROTOOPT  92  /* Protocol not available */
+#define  EPROTONOSUPPORT 93  /* Protocol not supported */
+#define  ESOCKTNOSUPPORT 94  /* Socket type not supported */
+#define  EOPNOTSUPP      95  /* Operation not supported on transport endpoint */
+#define  EPFNOSUPPORT    96  /* Protocol family not supported */
+#define  EAFNOSUPPORT    97  /* Address family not supported by protocol */
+#define  EADDRINUSE      98  /* Address already in use */
+#define  EADDRNOTAVAIL   99  /* Cannot assign requested address */
+#define  ENETDOWN       100  /* Network is down */
+#define  ENETUNREACH    101  /* Network is unreachable */
+#define  ENETRESET      102  /* Network dropped connection because of reset */
+#define  ECONNABORTED   103  /* Software caused connection abort */
+#define  ECONNRESET     104  /* Connection reset by peer */
+#define  ENOBUFS        105  /* No buffer space available */
+#define  EISCONN        106  /* Transport endpoint is already connected */
+#define  ENOTCONN       107  /* Transport endpoint is not connected */
+#define  ESHUTDOWN      108  /* Cannot send after transport endpoint shutdown */
+#define  ETOOMANYREFS   109  /* Too many references: cannot splice */
+#define  ETIMEDOUT      110  /* Connection timed out */
+#define  ECONNREFUSED   111  /* Connection refused */
+#define  EHOSTDOWN      112  /* Host is down */
+#define  EHOSTUNREACH   113  /* No route to host */
+#define  EALREADY       114  /* Operation already in progress */
+#define  EINPROGRESS    115  /* Operation now in progress */
+#define  ESTALE         116  /* Stale NFS file handle */
+#define  EUCLEAN        117  /* Structure needs cleaning */
+#define  ENOTNAM        118  /* Not a XENIX named type file */
+#define  ENAVAIL        119  /* No XENIX semaphores available */
+#define  EISNAM         120  /* Is a named type file */
+#define  EREMOTEIO      121  /* Remote I/O error */
+#define  EDQUOT         122  /* Quota exceeded */
+
+#define  ENOMEDIUM      123  /* No medium found */
+#define  EMEDIUMTYPE    124  /* Wrong medium type */
+
+
+#define ENSROK                    0 /* DNS server returned answer with no data */
+#define ENSRNODATA              160 /* DNS server returned answer with no data */
+#define ENSRFORMERR             161 /* DNS server claims query was misformatted */
+#define ENSRSERVFAIL            162 /* DNS server returned general failure */
+#define ENSRNOTFOUND            163 /* Domain name not found */
+#define ENSRNOTIMP              164 /* DNS server does not implement requested operation */
+#define ENSRREFUSED             165 /* DNS server refused query */
+#define ENSRBADQUERY            166 /* Misformatted DNS query */
+#define ENSRBADNAME             167 /* Misformatted domain name */
+#define ENSRBADFAMILY           168 /* Unsupported address family */
+#define ENSRBADRESP             169 /* Misformatted DNS reply */
+#define ENSRCONNREFUSED         170 /* Could not contact DNS servers */
+#define ENSRTIMEOUT             171 /* Timeout while contacting DNS servers */
+#define ENSROF                  172 /* End of file */
+#define ENSRFILE                173 /* Error reading file */
+#define ENSRNOMEM               174 /* Out of memory */
+#define ENSRDESTRUCTION         175 /* Application terminated lookup */
+#define ENSRQUERYDOMAINTOOLONG  176 /* Domain name is too long */
+#define ENSRCNAMELOOP           177 /* Domain name is too long */
+
+#ifndef errno
+extern int errno;
+#endif
+
+#endif /* LWIP_PROVIDE_ERRNO */
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __LWIP_ARCH_H__ */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/include/lwip/debug.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,98 @@
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+#ifndef __LWIP_DEBUG_H__
+#define __LWIP_DEBUG_H__
+
+#include "lwip/arch.h"
+
+/** lower two bits indicate debug level
+ * - 0 all
+ * - 1 warning
+ * - 2 serious
+ * - 3 severe
+ */
+#define LWIP_DBG_LEVEL_ALL     0x00
+#define LWIP_DBG_LEVEL_OFF     LWIP_DBG_LEVEL_ALL /* compatibility define only */
+#define LWIP_DBG_LEVEL_WARNING 0x01 /* bad checksums, dropped packets, ... */
+#define LWIP_DBG_LEVEL_SERIOUS 0x02 /* memory allocation failures, ... */
+#define LWIP_DBG_LEVEL_SEVERE  0x03
+#define LWIP_DBG_MASK_LEVEL    0x03
+
+/** flag for LWIP_DEBUGF to enable that debug message */
+#define LWIP_DBG_ON            0x80U
+/** flag for LWIP_DEBUGF to disable that debug message */
+#define LWIP_DBG_OFF           0x00U
+
+/** flag for LWIP_DEBUGF indicating a tracing message (to follow program flow) */
+#define LWIP_DBG_TRACE         0x40U
+/** flag for LWIP_DEBUGF indicating a state debug message (to follow module states) */
+#define LWIP_DBG_STATE         0x20U
+/** flag for LWIP_DEBUGF indicating newly added code, not thoroughly tested yet */
+#define LWIP_DBG_FRESH         0x10U
+/** flag for LWIP_DEBUGF to halt after printing this debug message */
+#define LWIP_DBG_HALT          0x08U
+
+#ifndef LWIP_NOASSERT
+#define LWIP_ASSERT(message, assertion) do { if(!(assertion)) \
+  LWIP_PLATFORM_ASSERT(message); } while(0)
+#else  /* LWIP_NOASSERT */
+#define LWIP_ASSERT(message, assertion) 
+#endif /* LWIP_NOASSERT */
+
+/** if "expression" isn't true, then print "message" and execute "handler" expression */
+#ifndef LWIP_ERROR
+#define LWIP_ERROR(message, expression, handler) do { if (!(expression)) { \
+  LWIP_PLATFORM_ASSERT(message); handler;}} while(0)
+#endif /* LWIP_ERROR */
+
+#ifdef LWIP_DEBUG
+/** print debug message only if debug message type is enabled...
+ *  AND is of correct type AND is at least LWIP_DBG_LEVEL
+ */
+#define LWIP_DEBUGF(debug, message) do { \
+                               if ( \
+                                   ((debug) & LWIP_DBG_ON) && \
+                                   ((debug) & LWIP_DBG_TYPES_ON) && \
+                                   ((s16_t)((debug) & LWIP_DBG_MASK_LEVEL) >= LWIP_DBG_MIN_LEVEL)) { \
+                                 LWIP_PLATFORM_DIAG(message); \
+                                 if ((debug) & LWIP_DBG_HALT) { \
+                                   while(1); \
+                                 } \
+                               } \
+                             } while(0)
+
+#else  /* LWIP_DEBUG */
+#define LWIP_DEBUGF(debug, message) 
+#endif /* LWIP_DEBUG */
+
+#endif /* __LWIP_DEBUG_H__ */
+
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/include/lwip/def.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,127 @@
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+#ifndef __LWIP_DEF_H__
+#define __LWIP_DEF_H__
+
+/* arch.h might define NULL already */
+#include "lwip/arch.h"
+#include "lwip/opt.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#define LWIP_MAX(x , y)  (((x) > (y)) ? (x) : (y))
+#define LWIP_MIN(x , y)  (((x) < (y)) ? (x) : (y))
+
+#ifndef NULL
+#define NULL ((void *)0)
+#endif
+
+/** Get the absolute difference between 2 u32_t values (correcting overflows)
+ * 'a' is expected to be 'higher' (without overflow) than 'b'. */
+#define LWIP_U32_DIFF(a, b) (((a) >= (b)) ? ((a) - (b)) : (((a) + ((b) ^ 0xFFFFFFFF) + 1))) 
+
+/* Endianess-optimized shifting of two u8_t to create one u16_t */
+#if BYTE_ORDER == LITTLE_ENDIAN
+#define LWIP_MAKE_U16(a, b) ((a << 8) | b)
+#else
+#define LWIP_MAKE_U16(a, b) ((b << 8) | a)
+#endif 
+
+#ifndef LWIP_PLATFORM_BYTESWAP
+#define LWIP_PLATFORM_BYTESWAP 0
+#endif
+
+#ifndef LWIP_PREFIX_BYTEORDER_FUNCS
+/* workaround for naming collisions on some platforms */
+
+#ifdef htons
+#undef htons
+#endif /* htons */
+#ifdef htonl
+#undef htonl
+#endif /* htonl */
+#ifdef ntohs
+#undef ntohs
+#endif /* ntohs */
+#ifdef ntohl
+#undef ntohl
+#endif /* ntohl */
+
+#define htons(x) lwip_htons(x)
+#define ntohs(x) lwip_ntohs(x)
+#define htonl(x) lwip_htonl(x)
+#define ntohl(x) lwip_ntohl(x)
+#endif /* LWIP_PREFIX_BYTEORDER_FUNCS */
+
+#if BYTE_ORDER == BIG_ENDIAN
+#define lwip_htons(x) (x)
+#define lwip_ntohs(x) (x)
+#define lwip_htonl(x) (x)
+#define lwip_ntohl(x) (x)
+#define PP_HTONS(x) (x)
+#define PP_NTOHS(x) (x)
+#define PP_HTONL(x) (x)
+#define PP_NTOHL(x) (x)
+#else /* BYTE_ORDER != BIG_ENDIAN */
+#if LWIP_PLATFORM_BYTESWAP
+#define lwip_htons(x) LWIP_PLATFORM_HTONS(x)
+#define lwip_ntohs(x) LWIP_PLATFORM_HTONS(x)
+#define lwip_htonl(x) LWIP_PLATFORM_HTONL(x)
+#define lwip_ntohl(x) LWIP_PLATFORM_HTONL(x)
+#else /* LWIP_PLATFORM_BYTESWAP */
+u16_t lwip_htons(u16_t x);
+u16_t lwip_ntohs(u16_t x);
+u32_t lwip_htonl(u32_t x);
+u32_t lwip_ntohl(u32_t x);
+#endif /* LWIP_PLATFORM_BYTESWAP */
+
+/* These macros should be calculated by the preprocessor and are used
+   with compile-time constants only (so that there is no little-endian
+   overhead at runtime). */
+#define PP_HTONS(x) ((((x) & 0xff) << 8) | (((x) & 0xff00) >> 8))
+#define PP_NTOHS(x) PP_HTONS(x)
+#define PP_HTONL(x) ((((x) & 0xff) << 24) | \
+                     (((x) & 0xff00) << 8) | \
+                     (((x) & 0xff0000UL) >> 8) | \
+                     (((x) & 0xff000000UL) >> 24))
+#define PP_NTOHL(x) PP_HTONL(x)
+
+#endif /* BYTE_ORDER == BIG_ENDIAN */
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __LWIP_DEF_H__ */
+
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/include/lwip/dhcp.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,239 @@
+/** @file
+ */
+
+#ifndef __LWIP_DHCP_H__
+#define __LWIP_DHCP_H__
+
+#include "lwip/opt.h"
+
+#if LWIP_DHCP /* don't build if not configured for use in lwipopts.h */
+
+#include "lwip/netif.h"
+#include "lwip/udp.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/** period (in seconds) of the application calling dhcp_coarse_tmr() */
+#define DHCP_COARSE_TIMER_SECS 60 
+/** period (in milliseconds) of the application calling dhcp_coarse_tmr() */
+#define DHCP_COARSE_TIMER_MSECS (DHCP_COARSE_TIMER_SECS * 1000UL)
+/** period (in milliseconds) of the application calling dhcp_fine_tmr() */
+#define DHCP_FINE_TIMER_MSECS 500 
+
+#define DHCP_CHADDR_LEN 16U
+#define DHCP_SNAME_LEN  64U
+#define DHCP_FILE_LEN   128U
+
+struct dhcp
+{
+  /** transaction identifier of last sent request */ 
+  u32_t xid;
+  /** our connection to the DHCP server */ 
+  struct udp_pcb *pcb;
+  /** incoming msg */
+  struct dhcp_msg *msg_in;
+  /** current DHCP state machine state */
+  u8_t state;
+  /** retries of current request */
+  u8_t tries;
+#if LWIP_DHCP_AUTOIP_COOP
+  u8_t autoip_coop_state;
+#endif
+  u8_t subnet_mask_given;
+
+  struct pbuf *p_out; /* pbuf of outcoming msg */
+  struct dhcp_msg *msg_out; /* outgoing msg */
+  u16_t options_out_len; /* outgoing msg options length */
+  u16_t request_timeout; /* #ticks with period DHCP_FINE_TIMER_SECS for request timeout */
+  u16_t t1_timeout;  /* #ticks with period DHCP_COARSE_TIMER_SECS for renewal time */
+  u16_t t2_timeout;  /* #ticks with period DHCP_COARSE_TIMER_SECS for rebind time */
+  ip_addr_t server_ip_addr; /* dhcp server address that offered this lease */
+  ip_addr_t offered_ip_addr;
+  ip_addr_t offered_sn_mask;
+  ip_addr_t offered_gw_addr;
+ 
+  u32_t offered_t0_lease; /* lease period (in seconds) */
+  u32_t offered_t1_renew; /* recommended renew time (usually 50% of lease period) */
+  u32_t offered_t2_rebind; /* recommended rebind time (usually 66% of lease period)  */
+  /* @todo: LWIP_DHCP_BOOTP_FILE configuration option?
+     integrate with possible TFTP-client for booting? */
+#if LWIP_DHCP_BOOTP_FILE
+  ip_addr_t offered_si_addr;
+  char boot_file_name[DHCP_FILE_LEN];
+#endif /* LWIP_DHCP_BOOTPFILE */
+};
+
+/* MUST be compiled with "pack structs" or equivalent! */
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/bpstruct.h"
+#endif
+PACK_STRUCT_BEGIN
+/** minimum set of fields of any DHCP message */
+struct dhcp_msg
+{
+  PACK_STRUCT_FIELD(u8_t op);
+  PACK_STRUCT_FIELD(u8_t htype);
+  PACK_STRUCT_FIELD(u8_t hlen);
+  PACK_STRUCT_FIELD(u8_t hops);
+  PACK_STRUCT_FIELD(u32_t xid);
+  PACK_STRUCT_FIELD(u16_t secs);
+  PACK_STRUCT_FIELD(u16_t flags);
+  PACK_STRUCT_FIELD(ip_addr_p_t ciaddr);
+  PACK_STRUCT_FIELD(ip_addr_p_t yiaddr);
+  PACK_STRUCT_FIELD(ip_addr_p_t siaddr);
+  PACK_STRUCT_FIELD(ip_addr_p_t giaddr);
+  PACK_STRUCT_FIELD(u8_t chaddr[DHCP_CHADDR_LEN]);
+  PACK_STRUCT_FIELD(u8_t sname[DHCP_SNAME_LEN]);
+  PACK_STRUCT_FIELD(u8_t file[DHCP_FILE_LEN]);
+  PACK_STRUCT_FIELD(u32_t cookie);
+#define DHCP_MIN_OPTIONS_LEN 68U
+/** make sure user does not configure this too small */
+#if ((defined(DHCP_OPTIONS_LEN)) && (DHCP_OPTIONS_LEN < DHCP_MIN_OPTIONS_LEN))
+#  undef DHCP_OPTIONS_LEN
+#endif
+/** allow this to be configured in lwipopts.h, but not too small */
+#if (!defined(DHCP_OPTIONS_LEN))
+/** set this to be sufficient for your options in outgoing DHCP msgs */
+#  define DHCP_OPTIONS_LEN DHCP_MIN_OPTIONS_LEN
+#endif
+  PACK_STRUCT_FIELD(u8_t options[DHCP_OPTIONS_LEN]);
+} PACK_STRUCT_STRUCT;
+PACK_STRUCT_END
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/epstruct.h"
+#endif
+
+void dhcp_set_struct(struct netif *netif, struct dhcp *dhcp);
+/** start DHCP configuration */
+err_t dhcp_start(struct netif *netif);
+/** enforce early lease renewal (not needed normally)*/
+err_t dhcp_renew(struct netif *netif);
+/** release the DHCP lease, usually called before dhcp_stop()*/
+err_t dhcp_release(struct netif *netif);
+/** stop DHCP configuration */
+void dhcp_stop(struct netif *netif);
+/** inform server of our manual IP address */
+void dhcp_inform(struct netif *netif);
+/** Handle a possible change in the network configuration */
+void dhcp_network_changed(struct netif *netif);
+
+/** if enabled, check whether the offered IP address is not in use, using ARP */
+#if DHCP_DOES_ARP_CHECK
+void dhcp_arp_reply(struct netif *netif, ip_addr_t *addr);
+#endif
+
+/** to be called every minute */
+void dhcp_coarse_tmr(void);
+/** to be called every half second */
+void dhcp_fine_tmr(void);
+ 
+/** DHCP message item offsets and length */
+#define DHCP_OP_OFS       0
+#define DHCP_HTYPE_OFS    1
+#define DHCP_HLEN_OFS     2
+#define DHCP_HOPS_OFS     3
+#define DHCP_XID_OFS      4
+#define DHCP_SECS_OFS     8
+#define DHCP_FLAGS_OFS    10
+#define DHCP_CIADDR_OFS   12
+#define DHCP_YIADDR_OFS   16
+#define DHCP_SIADDR_OFS   20
+#define DHCP_GIADDR_OFS   24
+#define DHCP_CHADDR_OFS   28
+#define DHCP_SNAME_OFS    44
+#define DHCP_FILE_OFS     108
+#define DHCP_MSG_LEN      236
+
+#define DHCP_COOKIE_OFS   DHCP_MSG_LEN
+#define DHCP_OPTIONS_OFS  (DHCP_MSG_LEN + 4)
+
+#define DHCP_CLIENT_PORT  68  
+#define DHCP_SERVER_PORT  67
+
+/** DHCP client states */
+#define DHCP_OFF          0
+#define DHCP_REQUESTING   1
+#define DHCP_INIT         2
+#define DHCP_REBOOTING    3
+#define DHCP_REBINDING    4
+#define DHCP_RENEWING     5
+#define DHCP_SELECTING    6
+#define DHCP_INFORMING    7
+#define DHCP_CHECKING     8
+#define DHCP_PERMANENT    9
+#define DHCP_BOUND        10
+/** not yet implemented #define DHCP_RELEASING 11 */
+#define DHCP_BACKING_OFF  12
+
+/** AUTOIP cooperatation flags */
+#define DHCP_AUTOIP_COOP_STATE_OFF  0
+#define DHCP_AUTOIP_COOP_STATE_ON   1
+ 
+#define DHCP_BOOTREQUEST  1
+#define DHCP_BOOTREPLY    2
+
+/** DHCP message types */
+#define DHCP_DISCOVER 1
+#define DHCP_OFFER    2
+#define DHCP_REQUEST  3
+#define DHCP_DECLINE  4
+#define DHCP_ACK      5
+#define DHCP_NAK      6
+#define DHCP_RELEASE  7
+#define DHCP_INFORM   8
+
+/** DHCP hardware type, currently only ethernet is supported */
+#define DHCP_HTYPE_ETH 1
+
+#define DHCP_MAGIC_COOKIE 0x63825363UL
+
+/* This is a list of options for BOOTP and DHCP, see RFC 2132 for descriptions */
+
+/** BootP options */
+#define DHCP_OPTION_PAD 0
+#define DHCP_OPTION_SUBNET_MASK 1 /* RFC 2132 3.3 */
+#define DHCP_OPTION_ROUTER 3
+#define DHCP_OPTION_DNS_SERVER 6 
+#define DHCP_OPTION_HOSTNAME 12
+#define DHCP_OPTION_IP_TTL 23
+#define DHCP_OPTION_MTU 26
+#define DHCP_OPTION_BROADCAST 28
+#define DHCP_OPTION_TCP_TTL 37
+#define DHCP_OPTION_END 255
+
+/** DHCP options */
+#define DHCP_OPTION_REQUESTED_IP 50 /* RFC 2132 9.1, requested IP address */
+#define DHCP_OPTION_LEASE_TIME 51 /* RFC 2132 9.2, time in seconds, in 4 bytes */
+#define DHCP_OPTION_OVERLOAD 52 /* RFC2132 9.3, use file and/or sname field for options */
+
+#define DHCP_OPTION_MESSAGE_TYPE 53 /* RFC 2132 9.6, important for DHCP */
+#define DHCP_OPTION_MESSAGE_TYPE_LEN 1
+
+#define DHCP_OPTION_SERVER_ID 54 /* RFC 2132 9.7, server IP address */
+#define DHCP_OPTION_PARAMETER_REQUEST_LIST 55 /* RFC 2132 9.8, requested option types */
+
+#define DHCP_OPTION_MAX_MSG_SIZE 57 /* RFC 2132 9.10, message size accepted >= 576 */
+#define DHCP_OPTION_MAX_MSG_SIZE_LEN 2
+
+#define DHCP_OPTION_T1 58 /* T1 renewal time */
+#define DHCP_OPTION_T2 59 /* T2 rebinding time */
+#define DHCP_OPTION_US 60
+#define DHCP_OPTION_CLIENT_ID 61
+#define DHCP_OPTION_TFTP_SERVERNAME 66
+#define DHCP_OPTION_BOOTFILE 67
+
+/** possible combinations of overloading the file and sname fields with options */
+#define DHCP_OVERLOAD_NONE 0
+#define DHCP_OVERLOAD_FILE 1
+#define DHCP_OVERLOAD_SNAME  2
+#define DHCP_OVERLOAD_SNAME_FILE 3
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* LWIP_DHCP */
+
+#endif /*__LWIP_DHCP_H__*/
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/include/lwip/dns.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,116 @@
+/**
+ * lwip DNS resolver header file.
+
+ * Author: Jim Pettinato 
+ *   April 2007
+
+ * ported from uIP resolv.c Copyright (c) 2002-2003, Adam Dunkels.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote
+ *    products derived from this software without specific prior
+ *    written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
+ * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
+ * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef __LWIP_DNS_H__
+#define __LWIP_DNS_H__
+
+#include "lwip/opt.h"
+
+#if LWIP_DNS /* don't build if not configured for use in lwipopts.h */
+
+/** DNS timer period */
+#define DNS_TMR_INTERVAL          1000
+
+/** DNS field TYPE used for "Resource Records" */
+#define DNS_RRTYPE_A              1     /* a host address */
+#define DNS_RRTYPE_NS             2     /* an authoritative name server */
+#define DNS_RRTYPE_MD             3     /* a mail destination (Obsolete - use MX) */
+#define DNS_RRTYPE_MF             4     /* a mail forwarder (Obsolete - use MX) */
+#define DNS_RRTYPE_CNAME          5     /* the canonical name for an alias */
+#define DNS_RRTYPE_SOA            6     /* marks the start of a zone of authority */
+#define DNS_RRTYPE_MB             7     /* a mailbox domain name (EXPERIMENTAL) */
+#define DNS_RRTYPE_MG             8     /* a mail group member (EXPERIMENTAL) */
+#define DNS_RRTYPE_MR             9     /* a mail rename domain name (EXPERIMENTAL) */
+#define DNS_RRTYPE_NULL           10    /* a null RR (EXPERIMENTAL) */
+#define DNS_RRTYPE_WKS            11    /* a well known service description */
+#define DNS_RRTYPE_PTR            12    /* a domain name pointer */
+#define DNS_RRTYPE_HINFO          13    /* host information */
+#define DNS_RRTYPE_MINFO          14    /* mailbox or mail list information */
+#define DNS_RRTYPE_MX             15    /* mail exchange */
+#define DNS_RRTYPE_TXT            16    /* text strings */
+
+/** DNS field CLASS used for "Resource Records" */
+#define DNS_RRCLASS_IN            1     /* the Internet */
+#define DNS_RRCLASS_CS            2     /* the CSNET class (Obsolete - used only for examples in some obsolete RFCs) */
+#define DNS_RRCLASS_CH            3     /* the CHAOS class */
+#define DNS_RRCLASS_HS            4     /* Hesiod [Dyer 87] */
+#define DNS_RRCLASS_FLUSH         0x800 /* Flush bit */
+
+/* The size used for the next line is rather a hack, but it prevents including socket.h in all files
+   that include memp.h, and that would possibly break portability (since socket.h defines some types
+   and constants possibly already define by the OS).
+   Calculation rule:
+   sizeof(struct addrinfo) + sizeof(struct sockaddr_in) + DNS_MAX_NAME_LENGTH + 1 byte zero-termination */
+#define NETDB_ELEM_SIZE           (32 + 16 + DNS_MAX_NAME_LENGTH + 1)
+
+#if DNS_LOCAL_HOSTLIST
+/** struct used for local host-list */
+struct local_hostlist_entry {
+  /** static hostname */
+  const char *name;
+  /** static host address in network byteorder */
+  ip_addr_t addr;
+  struct local_hostlist_entry *next;
+};
+#if DNS_LOCAL_HOSTLIST_IS_DYNAMIC
+#ifndef DNS_LOCAL_HOSTLIST_MAX_NAMELEN
+#define DNS_LOCAL_HOSTLIST_MAX_NAMELEN  DNS_MAX_NAME_LENGTH
+#endif
+#define LOCALHOSTLIST_ELEM_SIZE ((sizeof(struct local_hostlist_entry) + DNS_LOCAL_HOSTLIST_MAX_NAMELEN + 1))
+#endif /* DNS_LOCAL_HOSTLIST_IS_DYNAMIC */
+#endif /* DNS_LOCAL_HOSTLIST */
+
+/** Callback which is invoked when a hostname is found.
+ * A function of this type must be implemented by the application using the DNS resolver.
+ * @param name pointer to the name that was looked up.
+ * @param ipaddr pointer to an ip_addr_t containing the IP address of the hostname,
+ *        or NULL if the name could not be found (or on any other error).
+ * @param callback_arg a user-specified callback argument passed to dns_gethostbyname
+*/
+typedef void (*dns_found_callback)(const char *name, ip_addr_t *ipaddr, void *callback_arg);
+
+void           dns_init(void);
+void           dns_tmr(void);
+void           dns_setserver(u8_t numdns, ip_addr_t *dnsserver);
+ip_addr_t      dns_getserver(u8_t numdns);
+err_t          dns_gethostbyname(const char *hostname, ip_addr_t *addr,
+                                 dns_found_callback found, void *callback_arg);
+
+#if DNS_LOCAL_HOSTLIST && DNS_LOCAL_HOSTLIST_IS_DYNAMIC
+int            dns_local_removehost(const char *hostname, const ip_addr_t *addr);
+err_t          dns_local_addhost(const char *hostname, const ip_addr_t *addr);
+#endif /* DNS_LOCAL_HOSTLIST && DNS_LOCAL_HOSTLIST_IS_DYNAMIC */
+
+#endif /* LWIP_DNS */
+
+#endif /* __LWIP_DNS_H__ */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/include/lwip/err.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,86 @@
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+#ifndef __LWIP_ERR_H__
+#define __LWIP_ERR_H__
+
+#include "lwip/opt.h"
+#include "lwip/arch.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/** Define LWIP_ERR_T in cc.h if you want to use
+ *  a different type for your platform (must be signed). */
+#ifdef LWIP_ERR_T
+typedef LWIP_ERR_T err_t;
+#else /* LWIP_ERR_T */
+typedef s8_t err_t;
+#endif /* LWIP_ERR_T*/
+
+/* Definitions for error constants. */
+
+#define ERR_OK          0    /* No error, everything OK. */
+#define ERR_MEM        -1    /* Out of memory error.     */
+#define ERR_BUF        -2    /* Buffer error.            */
+#define ERR_TIMEOUT    -3    /* Timeout.                 */
+#define ERR_RTE        -4    /* Routing problem.         */
+#define ERR_INPROGRESS -5    /* Operation in progress    */
+#define ERR_VAL        -6    /* Illegal value.           */
+#define ERR_WOULDBLOCK -7    /* Operation would block.   */
+
+#define ERR_IS_FATAL(e) ((e) < ERR_VAL)
+
+#define ERR_ABRT       -8    /* Connection aborted.      */
+#define ERR_RST        -9    /* Connection reset.        */
+#define ERR_CLSD       -10   /* Connection closed.       */
+#define ERR_CONN       -11   /* Not connected.           */
+
+#define ERR_ARG        -12   /* Illegal argument.        */
+
+#define ERR_USE        -13   /* Address in use.          */
+
+#define ERR_IF         -14   /* Low-level netif error    */
+#define ERR_ISCONN     -15   /* Already connected.       */
+
+
+#ifdef LWIP_DEBUG
+extern const char *lwip_strerr(err_t err);
+#else
+#define lwip_strerr(x) ""
+#endif /* LWIP_DEBUG */
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __LWIP_ERR_H__ */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/include/lwip/init.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,72 @@
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+#ifndef __LWIP_INIT_H__
+#define __LWIP_INIT_H__
+
+#include "lwip/opt.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/** X.x.x: Major version of the stack */
+#define LWIP_VERSION_MAJOR      1U
+/** x.X.x: Minor version of the stack */
+#define LWIP_VERSION_MINOR      4U
+/** x.x.X: Revision of the stack */
+#define LWIP_VERSION_REVISION   0U
+/** For release candidates, this is set to 1..254
+  * For official releases, this is set to 255 (LWIP_RC_RELEASE)
+  * For development versions (CVS), this is set to 0 (LWIP_RC_DEVELOPMENT) */
+#define LWIP_VERSION_RC         1U
+
+/** LWIP_VERSION_RC is set to LWIP_RC_RELEASE for official releases */
+#define LWIP_RC_RELEASE         255U
+/** LWIP_VERSION_RC is set to LWIP_RC_DEVELOPMENT for CVS versions */
+#define LWIP_RC_DEVELOPMENT     0U
+
+#define LWIP_VERSION_IS_RELEASE     (LWIP_VERSION_RC == LWIP_RC_RELEASE)
+#define LWIP_VERSION_IS_DEVELOPMENT (LWIP_VERSION_RC == LWIP_RC_DEVELOPMENT)
+#define LWIP_VERSION_IS_RC          ((LWIP_VERSION_RC != LWIP_RC_RELEASE) && (LWIP_VERSION_RC != LWIP_RC_DEVELOPMENT))
+
+/** Provides the version of the stack */
+#define LWIP_VERSION   (LWIP_VERSION_MAJOR << 24   | LWIP_VERSION_MINOR << 16 | \
+                        LWIP_VERSION_REVISION << 8 | LWIP_VERSION_RC)
+
+/* Modules initialization */
+void lwip_init(void);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __LWIP_INIT_H__ */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/include/lwip/mem.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,122 @@
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+#ifndef __LWIP_MEM_H__
+#define __LWIP_MEM_H__
+
+#include "lwip/opt.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#if MEM_LIBC_MALLOC
+
+#include <stddef.h> /* for size_t */
+
+typedef size_t mem_size_t;
+
+/* aliases for C library malloc() */
+#define mem_init()
+/* in case C library malloc() needs extra protection,
+ * allow these defines to be overridden.
+ */
+#ifndef mem_free
+#define mem_free free
+#endif
+#ifndef mem_malloc
+#define mem_malloc malloc
+#endif
+#ifndef mem_calloc
+#define mem_calloc calloc
+#endif
+/* Since there is no C library allocation function to shrink memory without
+   moving it, define this to nothing. */
+#ifndef mem_trim
+#define mem_trim(mem, size) (mem)
+#endif
+#else /* MEM_LIBC_MALLOC */
+
+/* MEM_SIZE would have to be aligned, but using 64000 here instead of
+ * 65535 leaves some room for alignment...
+ */
+#if MEM_SIZE > 64000l
+typedef u32_t mem_size_t;
+#define MEM_SIZE_F U32_F
+#else
+typedef u16_t mem_size_t;
+#define MEM_SIZE_F U16_F
+#endif /* MEM_SIZE > 64000 */
+
+#if MEM_USE_POOLS
+/** mem_init is not used when using pools instead of a heap */
+#define mem_init()
+/** mem_trim is not used when using pools instead of a heap:
+    we can't free part of a pool element and don't want to copy the rest */
+#define mem_trim(mem, size) (mem)
+#else /* MEM_USE_POOLS */
+/* lwIP alternative malloc */
+void  mem_init(void);
+void *mem_trim(void *mem, mem_size_t size);
+#endif /* MEM_USE_POOLS */
+void *mem_malloc(mem_size_t size);
+void *mem_calloc(mem_size_t count, mem_size_t size);
+void  mem_free(void *mem);
+#endif /* MEM_LIBC_MALLOC */
+
+/** Calculate memory size for an aligned buffer - returns the next highest
+ * multiple of MEM_ALIGNMENT (e.g. LWIP_MEM_ALIGN_SIZE(3) and
+ * LWIP_MEM_ALIGN_SIZE(4) will both yield 4 for MEM_ALIGNMENT == 4).
+ */
+#ifndef LWIP_MEM_ALIGN_SIZE
+#define LWIP_MEM_ALIGN_SIZE(size) (((size) + MEM_ALIGNMENT - 1) & ~(MEM_ALIGNMENT-1))
+#endif
+
+/** Calculate safe memory size for an aligned buffer when using an unaligned
+ * type as storage. This includes a safety-margin on (MEM_ALIGNMENT - 1) at the
+ * start (e.g. if buffer is u8_t[] and actual data will be u32_t*)
+ */
+#ifndef LWIP_MEM_ALIGN_BUFFER
+#define LWIP_MEM_ALIGN_BUFFER(size) (((size) + MEM_ALIGNMENT - 1))
+#endif
+
+/** Align a memory pointer to the alignment defined by MEM_ALIGNMENT
+ * so that ADDR % MEM_ALIGNMENT == 0
+ */
+#ifndef LWIP_MEM_ALIGN
+#define LWIP_MEM_ALIGN(addr) ((void *)(((mem_ptr_t)(addr) + MEM_ALIGNMENT - 1) & ~(mem_ptr_t)(MEM_ALIGNMENT-1)))
+#endif
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __LWIP_MEM_H__ */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/include/lwip/memp.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,116 @@
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+
+#ifndef __LWIP_MEMP_H__
+#define __LWIP_MEMP_H__
+
+#include "lwip/opt.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* Create the list of all memory pools managed by memp. MEMP_MAX represents a NULL pool at the end */
+typedef enum {
+#define LWIP_MEMPOOL(name,num,size,desc)  MEMP_##name,
+#include "lwip/memp_std.h"
+  MEMP_MAX
+} memp_t;
+
+#if MEM_USE_POOLS
+/* Use a helper type to get the start and end of the user "memory pools" for mem_malloc */
+typedef enum {
+    /* Get the first (via:
+       MEMP_POOL_HELPER_START = ((u8_t) 1*MEMP_POOL_A + 0*MEMP_POOL_B + 0*MEMP_POOL_C + 0)*/
+    MEMP_POOL_HELPER_FIRST = ((u8_t)
+#define LWIP_MEMPOOL(name,num,size,desc)
+#define LWIP_MALLOC_MEMPOOL_START 1
+#define LWIP_MALLOC_MEMPOOL(num, size) * MEMP_POOL_##size + 0
+#define LWIP_MALLOC_MEMPOOL_END
+#include "lwip/memp_std.h"
+    ) ,
+    /* Get the last (via:
+       MEMP_POOL_HELPER_END = ((u8_t) 0 + MEMP_POOL_A*0 + MEMP_POOL_B*0 + MEMP_POOL_C*1) */
+    MEMP_POOL_HELPER_LAST = ((u8_t)
+#define LWIP_MEMPOOL(name,num,size,desc)
+#define LWIP_MALLOC_MEMPOOL_START
+#define LWIP_MALLOC_MEMPOOL(num, size) 0 + MEMP_POOL_##size *
+#define LWIP_MALLOC_MEMPOOL_END 1
+#include "lwip/memp_std.h"
+    )
+} memp_pool_helper_t;
+
+/* The actual start and stop values are here (cast them over)
+   We use this helper type and these defines so we can avoid using const memp_t values */
+#define MEMP_POOL_FIRST ((memp_t) MEMP_POOL_HELPER_FIRST)
+#define MEMP_POOL_LAST   ((memp_t) MEMP_POOL_HELPER_LAST)
+#endif /* MEM_USE_POOLS */
+
+#if MEMP_MEM_MALLOC || MEM_USE_POOLS
+extern const u16_t memp_sizes[MEMP_MAX];
+#endif /* MEMP_MEM_MALLOC || MEM_USE_POOLS */
+
+#if MEMP_MEM_MALLOC
+
+#include "mem.h"
+
+#define memp_init()
+#define memp_malloc(type)     mem_malloc(memp_sizes[type])
+#define memp_free(type, mem)  mem_free(mem)
+
+#else /* MEMP_MEM_MALLOC */
+
+#if MEM_USE_POOLS
+/** This structure is used to save the pool one element came from. */
+struct memp_malloc_helper
+{
+   memp_t poolnr;
+};
+#endif /* MEM_USE_POOLS */
+
+void  memp_init(void);
+
+#if MEMP_OVERFLOW_CHECK
+void *memp_malloc_fn(memp_t type, const char* file, const int line);
+#define memp_malloc(t) memp_malloc_fn((t), __FILE__, __LINE__)
+#else
+void *memp_malloc(memp_t type);
+#endif
+void  memp_free(memp_t type, void *mem);
+
+#endif /* MEMP_MEM_MALLOC */
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __LWIP_MEMP_H__ */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/include/lwip/memp_std.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,122 @@
+/*
+ * SETUP: Make sure we define everything we will need.
+ *
+ * We have create three types of pools:
+ *   1) MEMPOOL - standard pools
+ *   2) MALLOC_MEMPOOL - to be used by mem_malloc in mem.c
+ *   3) PBUF_MEMPOOL - a mempool of pbuf's, so include space for the pbuf struct
+ *
+ * If the include'r doesn't require any special treatment of each of the types
+ * above, then will declare #2 & #3 to be just standard mempools.
+ */
+#ifndef LWIP_MALLOC_MEMPOOL
+/* This treats "malloc pools" just like any other pool.
+   The pools are a little bigger to provide 'size' as the amount of user data. */
+#define LWIP_MALLOC_MEMPOOL(num, size) LWIP_MEMPOOL(POOL_##size, num, (size + sizeof(struct memp_malloc_helper)), "MALLOC_"#size)
+#define LWIP_MALLOC_MEMPOOL_START
+#define LWIP_MALLOC_MEMPOOL_END
+#endif /* LWIP_MALLOC_MEMPOOL */ 
+
+#ifndef LWIP_PBUF_MEMPOOL
+/* This treats "pbuf pools" just like any other pool.
+ * Allocates buffers for a pbuf struct AND a payload size */
+#define LWIP_PBUF_MEMPOOL(name, num, payload, desc) LWIP_MEMPOOL(name, num, (MEMP_ALIGN_SIZE(sizeof(struct pbuf)) + MEMP_ALIGN_SIZE(payload)), desc)
+#endif /* LWIP_PBUF_MEMPOOL */
+
+
+/*
+ * A list of internal pools used by LWIP.
+ *
+ * LWIP_MEMPOOL(pool_name, number_elements, element_size, pool_description)
+ *     creates a pool name MEMP_pool_name. description is used in stats.c
+ */
+#if LWIP_RAW
+LWIP_MEMPOOL(RAW_PCB,        MEMP_NUM_RAW_PCB,         sizeof(struct raw_pcb),        "RAW_PCB")
+#endif /* LWIP_RAW */
+
+#if LWIP_UDP
+LWIP_MEMPOOL(UDP_PCB,        MEMP_NUM_UDP_PCB,         sizeof(struct udp_pcb),        "UDP_PCB")
+#endif /* LWIP_UDP */
+
+#if LWIP_TCP
+LWIP_MEMPOOL(TCP_PCB,        MEMP_NUM_TCP_PCB,         sizeof(struct tcp_pcb),        "TCP_PCB")
+LWIP_MEMPOOL(TCP_PCB_LISTEN, MEMP_NUM_TCP_PCB_LISTEN,  sizeof(struct tcp_pcb_listen), "TCP_PCB_LISTEN")
+LWIP_MEMPOOL(TCP_SEG,        MEMP_NUM_TCP_SEG,         sizeof(struct tcp_seg),        "TCP_SEG")
+#endif /* LWIP_TCP */
+
+#if IP_REASSEMBLY
+LWIP_MEMPOOL(REASSDATA,      MEMP_NUM_REASSDATA,       sizeof(struct ip_reassdata),   "REASSDATA")
+#endif /* IP_REASSEMBLY */
+#if IP_FRAG && !IP_FRAG_USES_STATIC_BUF && !LWIP_NETIF_TX_SINGLE_PBUF
+LWIP_MEMPOOL(FRAG_PBUF,      MEMP_NUM_FRAG_PBUF,       sizeof(struct pbuf_custom_ref),"FRAG_PBUF")
+#endif /* IP_FRAG && !IP_FRAG_USES_STATIC_BUF && !LWIP_NETIF_TX_SINGLE_PBUF */
+
+#if LWIP_NETCONN
+LWIP_MEMPOOL(NETBUF,         MEMP_NUM_NETBUF,          sizeof(struct netbuf),         "NETBUF")
+LWIP_MEMPOOL(NETCONN,        MEMP_NUM_NETCONN,         sizeof(struct netconn),        "NETCONN")
+#endif /* LWIP_NETCONN */
+
+#if NO_SYS==0
+LWIP_MEMPOOL(TCPIP_MSG_API,  MEMP_NUM_TCPIP_MSG_API,   sizeof(struct tcpip_msg),      "TCPIP_MSG_API")
+#if !LWIP_TCPIP_CORE_LOCKING_INPUT
+LWIP_MEMPOOL(TCPIP_MSG_INPKT,MEMP_NUM_TCPIP_MSG_INPKT, sizeof(struct tcpip_msg),      "TCPIP_MSG_INPKT")
+#endif /* !LWIP_TCPIP_CORE_LOCKING_INPUT */
+#endif /* NO_SYS==0 */
+
+#if ARP_QUEUEING
+LWIP_MEMPOOL(ARP_QUEUE,      MEMP_NUM_ARP_QUEUE,       sizeof(struct etharp_q_entry), "ARP_QUEUE")
+#endif /* ARP_QUEUEING */
+
+#if LWIP_IGMP
+LWIP_MEMPOOL(IGMP_GROUP,     MEMP_NUM_IGMP_GROUP,      sizeof(struct igmp_group),     "IGMP_GROUP")
+#endif /* LWIP_IGMP */
+
+#if (!NO_SYS || (NO_SYS && !NO_SYS_NO_TIMERS)) /* LWIP_TIMERS */
+LWIP_MEMPOOL(SYS_TIMEOUT,    MEMP_NUM_SYS_TIMEOUT,     sizeof(struct sys_timeo),      "SYS_TIMEOUT")
+#endif /* LWIP_TIMERS */
+
+#if LWIP_SNMP
+LWIP_MEMPOOL(SNMP_ROOTNODE,  MEMP_NUM_SNMP_ROOTNODE,   sizeof(struct mib_list_rootnode), "SNMP_ROOTNODE")
+LWIP_MEMPOOL(SNMP_NODE,      MEMP_NUM_SNMP_NODE,       sizeof(struct mib_list_node),     "SNMP_NODE")
+LWIP_MEMPOOL(SNMP_VARBIND,   MEMP_NUM_SNMP_VARBIND,    sizeof(struct snmp_varbind),      "SNMP_VARBIND")
+LWIP_MEMPOOL(SNMP_VALUE,     MEMP_NUM_SNMP_VALUE,      SNMP_MAX_VALUE_SIZE,              "SNMP_VALUE")
+#endif /* LWIP_SNMP */
+#if LWIP_DNS && LWIP_SOCKET
+LWIP_MEMPOOL(NETDB,          MEMP_NUM_NETDB,           NETDB_ELEM_SIZE,               "NETDB")
+#endif /* LWIP_DNS && LWIP_SOCKET */
+#if LWIP_DNS && DNS_LOCAL_HOSTLIST && DNS_LOCAL_HOSTLIST_IS_DYNAMIC
+LWIP_MEMPOOL(LOCALHOSTLIST,  MEMP_NUM_LOCALHOSTLIST,   LOCALHOSTLIST_ELEM_SIZE,       "LOCALHOSTLIST")
+#endif /* LWIP_DNS && DNS_LOCAL_HOSTLIST && DNS_LOCAL_HOSTLIST_IS_DYNAMIC */
+#if PPP_SUPPORT && PPPOE_SUPPORT
+LWIP_MEMPOOL(PPPOE_IF,      MEMP_NUM_PPPOE_INTERFACES, sizeof(struct pppoe_softc),    "PPPOE_IF")
+#endif /* PPP_SUPPORT && PPPOE_SUPPORT */
+
+/*
+ * A list of pools of pbuf's used by LWIP.
+ *
+ * LWIP_PBUF_MEMPOOL(pool_name, number_elements, pbuf_payload_size, pool_description)
+ *     creates a pool name MEMP_pool_name. description is used in stats.c
+ *     This allocates enough space for the pbuf struct and a payload.
+ *     (Example: pbuf_payload_size=0 allocates only size for the struct)
+ */
+LWIP_PBUF_MEMPOOL(PBUF,      MEMP_NUM_PBUF,            0,                             "PBUF_REF/ROM")
+LWIP_PBUF_MEMPOOL(PBUF_POOL, PBUF_POOL_SIZE,           PBUF_POOL_BUFSIZE,             "PBUF_POOL")
+
+
+/*
+ * Allow for user-defined pools; this must be explicitly set in lwipopts.h
+ * since the default is to NOT look for lwippools.h
+ */
+#if MEMP_USE_CUSTOM_POOLS
+#include "lwippools.h"
+#endif /* MEMP_USE_CUSTOM_POOLS */
+
+/*
+ * REQUIRED CLEANUP: Clear up so we don't get "multiply defined" error later
+ * (#undef is ignored for something that is not defined)
+ */
+#undef LWIP_MEMPOOL
+#undef LWIP_MALLOC_MEMPOOL
+#undef LWIP_MALLOC_MEMPOOL_START
+#undef LWIP_MALLOC_MEMPOOL_END
+#undef LWIP_PBUF_MEMPOOL
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/include/lwip/netbuf.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,101 @@
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+#ifndef __LWIP_NETBUF_H__
+#define __LWIP_NETBUF_H__
+
+#include "lwip/opt.h"
+#include "lwip/pbuf.h"
+#include "lwip/ip_addr.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/** This netbuf has dest-addr/port set */
+#define NETBUF_FLAG_DESTADDR    0x01
+/** This netbuf includes a checksum */
+#define NETBUF_FLAG_CHKSUM      0x02
+
+struct netbuf {
+  struct pbuf *p, *ptr;
+  ip_addr_t addr;
+  u16_t port;
+#if LWIP_NETBUF_RECVINFO || LWIP_CHECKSUM_ON_COPY
+#if LWIP_CHECKSUM_ON_COPY
+  u8_t flags;
+#endif /* LWIP_CHECKSUM_ON_COPY */
+  u16_t toport_chksum;
+#if LWIP_NETBUF_RECVINFO
+  ip_addr_t toaddr;
+#endif /* LWIP_NETBUF_RECVINFO */
+#endif /* LWIP_NETBUF_RECVINFO || LWIP_CHECKSUM_ON_COPY */
+};
+
+/* Network buffer functions: */
+struct netbuf *   netbuf_new      (void);
+void              netbuf_delete   (struct netbuf *buf);
+void *            netbuf_alloc    (struct netbuf *buf, u16_t size);
+void              netbuf_free     (struct netbuf *buf);
+err_t             netbuf_ref      (struct netbuf *buf,
+                                   const void *dataptr, u16_t size);
+void              netbuf_chain    (struct netbuf *head,
+           struct netbuf *tail);
+
+err_t             netbuf_data     (struct netbuf *buf,
+                                   void **dataptr, u16_t *len);
+s8_t              netbuf_next     (struct netbuf *buf);
+void              netbuf_first    (struct netbuf *buf);
+
+
+#define netbuf_copy_partial(buf, dataptr, len, offset) \
+  pbuf_copy_partial((buf)->p, (dataptr), (len), (offset))
+#define netbuf_copy(buf,dataptr,len) netbuf_copy_partial(buf, dataptr, len, 0)
+#define netbuf_take(buf, dataptr, len) pbuf_take((buf)->p, dataptr, len)
+#define netbuf_len(buf)              ((buf)->p->tot_len)
+#define netbuf_fromaddr(buf)         (&((buf)->addr))
+#define netbuf_set_fromaddr(buf, fromaddr) ip_addr_set((&(buf)->addr), fromaddr)
+#define netbuf_fromport(buf)         ((buf)->port)
+#if LWIP_NETBUF_RECVINFO
+#define netbuf_destaddr(buf)         (&((buf)->toaddr))
+#define netbuf_set_destaddr(buf, destaddr) ip_addr_set((&(buf)->addr), destaddr)
+#define netbuf_destport(buf)         (((buf)->flags & NETBUF_FLAG_DESTADDR) ? (buf)->toport_chksum : 0)
+#endif /* LWIP_NETBUF_RECVINFO */
+#if LWIP_CHECKSUM_ON_COPY
+#define netbuf_set_chksum(buf, chksum) do { (buf)->flags = NETBUF_FLAG_CHKSUM; \
+                                            (buf)->toport_chksum = chksum; } while(0)
+#endif /* LWIP_CHECKSUM_ON_COPY */
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __LWIP_NETBUF_H__ */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/include/lwip/netdb.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,116 @@
+/*
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Simon Goldschmidt
+ *
+ */
+#ifndef __LWIP_NETDB_H__
+#define __LWIP_NETDB_H__
+
+#include "lwip/opt.h"
+
+#if LWIP_DNS && LWIP_SOCKET
+
+#include <stddef.h> /* for size_t */
+
+#include "lwip/inet.h"
+#include "lwip/sockets.h"
+
+/* some rarely used options */
+#ifndef LWIP_DNS_API_DECLARE_H_ERRNO
+#define LWIP_DNS_API_DECLARE_H_ERRNO 1
+#endif
+
+#ifndef LWIP_DNS_API_DEFINE_ERRORS
+#define LWIP_DNS_API_DEFINE_ERRORS 1
+#endif
+
+#ifndef LWIP_DNS_API_DECLARE_STRUCTS
+#define LWIP_DNS_API_DECLARE_STRUCTS 1
+#endif
+
+#if LWIP_DNS_API_DEFINE_ERRORS
+/** Errors used by the DNS API functions, h_errno can be one of them */
+#define EAI_NONAME      200
+#define EAI_SERVICE     201
+#define EAI_FAIL        202
+#define EAI_MEMORY      203
+
+#define HOST_NOT_FOUND  210
+#define NO_DATA         211
+#define NO_RECOVERY     212
+#define TRY_AGAIN       213
+#endif /* LWIP_DNS_API_DEFINE_ERRORS */
+
+#if LWIP_DNS_API_DECLARE_STRUCTS
+struct hostent {
+    char  *h_name;      /* Official name of the host. */
+    char **h_aliases;   /* A pointer to an array of pointers to alternative host names,
+                           terminated by a null pointer. */
+    int    h_addrtype;  /* Address type. */
+    int    h_length;    /* The length, in bytes, of the address. */
+    char **h_addr_list; /* A pointer to an array of pointers to network addresses (in
+                           network byte order) for the host, terminated by a null pointer. */
+#define h_addr h_addr_list[0] /* for backward compatibility */
+};
+
+struct addrinfo {
+    int               ai_flags;      /* Input flags. */
+    int               ai_family;     /* Address family of socket. */
+    int               ai_socktype;   /* Socket type. */
+    int               ai_protocol;   /* Protocol of socket. */
+    socklen_t         ai_addrlen;    /* Length of socket address. */
+    struct sockaddr  *ai_addr;       /* Socket address of socket. */
+    char             *ai_canonname;  /* Canonical name of service location. */
+    struct addrinfo  *ai_next;       /* Pointer to next in list. */
+};
+#endif /* LWIP_DNS_API_DECLARE_STRUCTS */
+
+#if LWIP_DNS_API_DECLARE_H_ERRNO
+/* application accessable error code set by the DNS API functions */
+extern int h_errno;
+#endif /* LWIP_DNS_API_DECLARE_H_ERRNO*/
+
+struct hostent *lwip_gethostbyname(const char *name);
+int lwip_gethostbyname_r(const char *name, struct hostent *ret, char *buf,
+                size_t buflen, struct hostent **result, int *h_errnop);
+void lwip_freeaddrinfo(struct addrinfo *ai);
+int lwip_getaddrinfo(const char *nodename,
+       const char *servname,
+       const struct addrinfo *hints,
+       struct addrinfo **res);
+
+#if LWIP_COMPAT_SOCKETS
+#define gethostbyname(name) lwip_gethostbyname(name)
+#define gethostbyname_r(name, ret, buf, buflen, result, h_errnop) \
+       lwip_gethostbyname_r(name, ret, buf, buflen, result, h_errnop)
+#define freeaddrinfo(addrinfo) lwip_freeaddrinfo(addrinfo)
+#define getaddrinfo(nodname, servname, hints, res) \
+       lwip_getaddrinfo(nodname, servname, hints, res)
+#endif /* LWIP_COMPAT_SOCKETS */
+
+#endif /* LWIP_DNS && LWIP_SOCKET */
+
+#endif /* __LWIP_NETDB_H__ */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/include/lwip/netif.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,315 @@
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+#ifndef __LWIP_NETIF_H__
+#define __LWIP_NETIF_H__
+
+#include "lwip/opt.h"
+
+#define ENABLE_LOOPBACK (LWIP_NETIF_LOOPBACK || LWIP_HAVE_LOOPIF)
+
+#include "lwip/err.h"
+
+#include "lwip/ip_addr.h"
+
+#include "lwip/def.h"
+#include "lwip/pbuf.h"
+#if LWIP_DHCP
+struct dhcp;
+#endif
+#if LWIP_AUTOIP
+struct autoip;
+#endif
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* Throughout this file, IP addresses are expected to be in
+ * the same byte order as in IP_PCB. */
+
+/*  must be the maximum of all used hardware address lengths
+    across all types of interfaces in use */
+#define NETIF_MAX_HWADDR_LEN 6U
+
+/*  Whether the network interface is 'up'. This is
+ * a software flag used to control whether this network
+ * interface is enabled and processes traffic.
+ * It is set by the startup code (for static IP configuration) or
+ * by dhcp/autoip when an address has been assigned.
+ */
+#define NETIF_FLAG_UP           0x01U
+/*  If set, the netif has broadcast capability.
+ * Set by the netif driver in its init function. */
+#define NETIF_FLAG_BROADCAST    0x02U
+/*  If set, the netif is one end of a point-to-point connection.
+ * Set by the netif driver in its init function. */
+#define NETIF_FLAG_POINTTOPOINT 0x04U
+/*  If set, the interface is configured using DHCP.
+ * Set by the DHCP code when starting or stopping DHCP. */
+#define NETIF_FLAG_DHCP         0x08U
+/*  If set, the interface has an active link
+ *  (set by the network interface driver).
+ * Either set by the netif driver in its init function (if the link
+ * is up at that time) or at a later point once the link comes up
+ * (if link detection is supported by the hardware). */
+#define NETIF_FLAG_LINK_UP      0x10U
+/*  If set, the netif is an ethernet device using ARP.
+ * Set by the netif driver in its init function.
+ * Used to check input packet types and use of DHCP. */
+#define NETIF_FLAG_ETHARP       0x20U
+/*  If set, the netif is an ethernet device. It might not use
+ * ARP or TCP/IP if it is used for PPPoE only.
+ */
+#define NETIF_FLAG_ETHERNET     0x40U
+/*  If set, the netif has IGMP capability.
+ * Set by the netif driver in its init function. */
+#define NETIF_FLAG_IGMP         0x80U
+
+/*  Function prototype for netif init functions. Set up flags and output/linkoutput
+ * callback functions in this function.
+ *
+ * @param netif The netif to initialize
+ */
+typedef err_t (*netif_init_fn)(struct netif *netif);
+/*  Function prototype for netif->input functions. This function is saved as 'input'
+ * callback function in the netif struct. Call it when a packet has been received.
+ *
+ * @param p The received packet, copied into a pbuf
+ * @param inp The netif which received the packet
+ */
+typedef err_t (*netif_input_fn)(struct pbuf *p, struct netif *inp);
+/*  Function prototype for netif->output functions. Called by lwIP when a packet
+ * shall be sent. For ethernet netif, set this to 'etharp_output' and set
+ * 'linkoutput'.
+ *
+ * @param netif The netif which shall send a packet
+ * @param p The packet to send (p->payload points to IP header)
+ * @param ipaddr The IP address to which the packet shall be sent
+ */
+typedef err_t (*netif_output_fn)(struct netif *netif, struct pbuf *p,
+       ip_addr_t *ipaddr);
+/*  Function prototype for netif->linkoutput functions. Only used for ethernet
+ * netifs. This function is called by ARP when a packet shall be sent.
+ *
+ * @param netif The netif which shall send a packet
+ * @param p The packet to send (raw ethernet packet)
+ */
+typedef err_t (*netif_linkoutput_fn)(struct netif *netif, struct pbuf *p);
+/*  Function prototype for netif status- or link-callback functions. */
+typedef void (*netif_status_callback_fn)(struct netif *netif);
+/*  Function prototype for netif igmp_mac_filter functions */
+typedef err_t (*netif_igmp_mac_filter_fn)(struct netif *netif,
+       ip_addr_t *group, u8_t action);
+
+/*  Generic data structure used for all lwIP network interfaces.
+ *  The following fields should be filled in by the initialization
+ *  function for the device driver: hwaddr_len, hwaddr[], mtu, flags */
+struct netif {
+  /*  pointer to next in linked list */
+  struct netif *next;
+
+  /*  IP address configuration in network byte order */
+  ip_addr_t ip_addr;
+  ip_addr_t netmask;
+  ip_addr_t gw;
+
+  /*  This function is called by the network device driver
+   *  to pass a packet up the TCP/IP stack. */
+  netif_input_fn input;
+  /*  This function is called by the IP module when it wants
+   *  to send a packet on the interface. This function typically
+   *  first resolves the hardware address, then sends the packet. */
+  netif_output_fn output;
+  /*  This function is called by the ARP module when it wants
+   *  to send a packet on the interface. This function outputs
+   *  the pbuf as-is on the link medium. */
+  netif_linkoutput_fn linkoutput;
+#if LWIP_NETIF_STATUS_CALLBACK
+  /*  This function is called when the netif state is set to up or down
+   */
+  netif_status_callback_fn status_callback;
+#endif /* LWIP_NETIF_STATUS_CALLBACK */
+#if LWIP_NETIF_LINK_CALLBACK
+  /*  This function is called when the netif link is set to up or down
+   */
+  netif_status_callback_fn link_callback;
+#endif /* LWIP_NETIF_LINK_CALLBACK */
+  /*  This field can be set by the device driver and could point
+   *  to state information for the device. */
+  void *state;
+#if LWIP_DHCP
+  /*  the DHCP client state information for this netif */
+  struct dhcp *dhcp;
+#endif /* LWIP_DHCP */
+#if LWIP_AUTOIP
+  /*  the AutoIP client state information for this netif */
+  struct autoip *autoip;
+#endif
+#if LWIP_NETIF_HOSTNAME
+  /* the hostname for this netif, NULL is a valid value */
+  char*  hostname;
+#endif /* LWIP_NETIF_HOSTNAME */
+  /*  maximum transfer unit (in bytes) */
+  u16_t mtu;
+  /*  number of bytes used in hwaddr */
+  u8_t hwaddr_len;
+  /*  link level hardware address of this interface */
+  u8_t hwaddr[NETIF_MAX_HWADDR_LEN];
+  /*  flags (see NETIF_FLAG_ above) */
+  u8_t flags;
+  /*  descriptive abbreviation */
+  char name[2];
+  /*  number of this interface */
+  u8_t num;
+#if LWIP_SNMP
+  /*  link type (from "snmp_ifType" enum from snmp.h) */
+  u8_t link_type;
+  /*  (estimate) link speed */
+  u32_t link_speed;
+  /*  timestamp at last change made (up/down) */
+  u32_t ts;
+  /*  counters */
+  u32_t ifinoctets;
+  u32_t ifinucastpkts;
+  u32_t ifinnucastpkts;
+  u32_t ifindiscards;
+  u32_t ifoutoctets;
+  u32_t ifoutucastpkts;
+  u32_t ifoutnucastpkts;
+  u32_t ifoutdiscards;
+#endif /* LWIP_SNMP */
+#if LWIP_IGMP
+  /*  This function could be called to add or delete a entry in the multicast
+      filter table of the ethernet MAC.*/
+  netif_igmp_mac_filter_fn igmp_mac_filter;
+#endif /* LWIP_IGMP */
+#if LWIP_NETIF_HWADDRHINT
+  u8_t *addr_hint;
+#endif /* LWIP_NETIF_HWADDRHINT */
+#if ENABLE_LOOPBACK
+  /* List of packets to be queued for ourselves. */
+  struct pbuf *loop_first;
+  struct pbuf *loop_last;
+#if LWIP_LOOPBACK_MAX_PBUFS
+  u16_t loop_cnt_current;
+#endif /* LWIP_LOOPBACK_MAX_PBUFS */
+#endif /* ENABLE_LOOPBACK */
+};
+
+#if LWIP_SNMP
+#define NETIF_INIT_SNMP(netif, type, speed) \
+  /* use "snmp_ifType" enum from snmp.h for "type", snmp_ifType_ethernet_csmacd by example */ \
+  (netif)->link_type = (type);    \
+  /* your link speed here (units: bits per second) */  \
+  (netif)->link_speed = (speed);  \
+  (netif)->ts = 0;              \
+  (netif)->ifinoctets = 0;      \
+  (netif)->ifinucastpkts = 0;   \
+  (netif)->ifinnucastpkts = 0;  \
+  (netif)->ifindiscards = 0;    \
+  (netif)->ifoutoctets = 0;     \
+  (netif)->ifoutucastpkts = 0;  \
+  (netif)->ifoutnucastpkts = 0; \
+  (netif)->ifoutdiscards = 0
+#else /* LWIP_SNMP */
+#define NETIF_INIT_SNMP(netif, type, speed)
+#endif /* LWIP_SNMP */
+
+
+/*  The list of network interfaces. */
+extern struct netif *netif_list;
+/*  The default network interface. */
+extern struct netif *netif_default;
+
+void netif_init(void);
+
+struct netif *netif_add(struct netif *netif, ip_addr_t *ipaddr, ip_addr_t *netmask,
+      ip_addr_t *gw, void *state, netif_init_fn init, netif_input_fn input);
+
+void
+netif_set_addr(struct netif *netif, ip_addr_t *ipaddr, ip_addr_t *netmask,
+      ip_addr_t *gw);
+void netif_remove(struct netif * netif);
+
+/* Returns a network interface given its name. The name is of the form
+   "et0", where the first two letters are the "name" field in the
+   netif structure, and the digit is in the num field in the same
+   structure. */
+struct netif *netif_find(char *name);
+
+void netif_set_default(struct netif *netif);
+
+void netif_set_ipaddr(struct netif *netif, ip_addr_t *ipaddr);
+void netif_set_netmask(struct netif *netif, ip_addr_t *netmask);
+void netif_set_gw(struct netif *netif, ip_addr_t *gw);
+
+void netif_set_up(struct netif *netif);
+void netif_set_down(struct netif *netif);
+/*  Ask if an interface is up */
+#define netif_is_up(netif) (((netif)->flags & NETIF_FLAG_UP) ? (u8_t)1 : (u8_t)0)
+
+#if LWIP_NETIF_STATUS_CALLBACK
+void netif_set_status_callback(struct netif *netif, netif_status_callback_fn status_callback);
+#endif /* LWIP_NETIF_STATUS_CALLBACK */
+
+void netif_set_link_up(struct netif *netif);
+void netif_set_link_down(struct netif *netif);
+/*  Ask if a link is up */ 
+#define netif_is_link_up(netif) (((netif)->flags & NETIF_FLAG_LINK_UP) ? (u8_t)1 : (u8_t)0)
+
+#if LWIP_NETIF_LINK_CALLBACK
+void netif_set_link_callback(struct netif *netif, netif_status_callback_fn link_callback);
+#endif /* LWIP_NETIF_LINK_CALLBACK */
+
+#if LWIP_NETIF_HOSTNAME
+#define netif_set_hostname(netif, name) do { if((netif) != NULL) { (netif)->hostname = name; }}while(0)
+#define netif_get_hostname(netif) (((netif) != NULL) ? ((netif)->hostname) : NULL)
+#endif /* LWIP_NETIF_HOSTNAME */
+
+#if LWIP_IGMP
+#define netif_set_igmp_mac_filter(netif, function) do { if((netif) != NULL) { (netif)->igmp_mac_filter = function; }}while(0)
+#define netif_get_igmp_mac_filter(netif) (((netif) != NULL) ? ((netif)->igmp_mac_filter) : NULL)
+#endif /* LWIP_IGMP */
+
+#if ENABLE_LOOPBACK
+err_t netif_loop_output(struct netif *netif, struct pbuf *p, ip_addr_t *dest_ip);
+void netif_poll(struct netif *netif);
+#if !LWIP_NETIF_LOOPBACK_MULTITHREADING
+void netif_poll_all(void);
+#endif /* !LWIP_NETIF_LOOPBACK_MULTITHREADING */
+#endif /* ENABLE_LOOPBACK */
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __LWIP_NETIF_H__ */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/include/lwip/netifapi.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,108 @@
+/*
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ */
+ 
+#ifndef __LWIP_NETIFAPI_H__
+#define __LWIP_NETIFAPI_H__
+
+#include "lwip/opt.h"
+
+#if LWIP_NETIF_API /* don't build if not configured for use in lwipopts.h */
+
+#include "lwip/sys.h"
+#include "lwip/netif.h"
+#include "lwip/dhcp.h"
+#include "lwip/autoip.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef void (*netifapi_void_fn)(struct netif *netif);
+typedef err_t (*netifapi_errt_fn)(struct netif *netif);
+
+struct netifapi_msg_msg {
+#if !LWIP_TCPIP_CORE_LOCKING
+  sys_sem_t sem;
+#endif /* !LWIP_TCPIP_CORE_LOCKING */
+  err_t err;
+  struct netif *netif;
+  union {
+    struct {
+      ip_addr_t *ipaddr;
+      ip_addr_t *netmask;
+      ip_addr_t *gw;
+      void *state;
+      netif_init_fn init;
+      netif_input_fn input;
+    } add;
+    struct {
+      netifapi_void_fn voidfunc;
+      netifapi_errt_fn errtfunc;
+    } common;
+  } msg;
+};
+
+struct netifapi_msg {
+  void (* function)(struct netifapi_msg_msg *msg);
+  struct netifapi_msg_msg msg;
+};
+
+
+/* API for application */
+err_t netifapi_netif_add       ( struct netif *netif,
+                                 ip_addr_t *ipaddr,
+                                 ip_addr_t *netmask,
+                                 ip_addr_t *gw,
+                                 void *state,
+                                 netif_init_fn init,
+                                 netif_input_fn input);
+
+err_t netifapi_netif_set_addr  ( struct netif *netif,
+                                 ip_addr_t *ipaddr,
+                                 ip_addr_t *netmask,
+                                 ip_addr_t *gw );
+
+err_t netifapi_netif_common    ( struct netif *netif,
+                                 netifapi_void_fn voidfunc,
+                                 netifapi_errt_fn errtfunc);
+
+#define netifapi_netif_remove(n)      netifapi_netif_common(n, netif_remove, NULL)
+#define netifapi_netif_set_up(n)      netifapi_netif_common(n, netif_set_up, NULL)
+#define netifapi_netif_set_down(n)    netifapi_netif_common(n, netif_set_down, NULL)
+#define netifapi_netif_set_default(n) netifapi_netif_common(n, netif_set_default, NULL)
+#define netifapi_dhcp_start(n)        netifapi_netif_common(n, NULL, dhcp_start)
+#define netifapi_dhcp_stop(n)         netifapi_netif_common(n, dhcp_stop, NULL)
+#define netifapi_autoip_start(n)      netifapi_netif_common(n, NULL, autoip_start)
+#define netifapi_autoip_stop(n)       netifapi_netif_common(n, NULL, autoip_stop)
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* LWIP_NETIF_API */
+
+#endif /* __LWIP_NETIFAPI_H__ */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/include/lwip/opt.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,2040 @@
+/**
+ * @file
+ *
+ * lwIP Options Configuration
+ */
+
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+#ifndef __LWIP_OPT_H__
+#define __LWIP_OPT_H__
+
+/*
+ * Include user defined options first. Anything not defined in these files
+ * will be set to standard values. Override anything you dont like!
+ */
+#include "lwipopts.h"
+#include "lwip/debug.h"
+
+/*
+   -----------------------------------------------
+   ---------- Platform specific locking ----------
+   -----------------------------------------------
+*/
+
+/**
+ * SYS_LIGHTWEIGHT_PROT==1: if you want inter-task protection for certain
+ * critical regions during buffer allocation, deallocation and memory
+ * allocation and deallocation.
+ */
+#ifndef SYS_LIGHTWEIGHT_PROT
+#define SYS_LIGHTWEIGHT_PROT            0
+#endif
+
+/** 
+ * NO_SYS==1: Provides VERY minimal functionality. Otherwise,
+ * use lwIP facilities.
+ */
+#ifndef NO_SYS
+#define NO_SYS                          0
+#endif
+
+/**
+ * NO_SYS_NO_TIMERS==1: Drop support for sys_timeout when NO_SYS==1
+ * Mainly for compatibility to old versions.
+ */
+#ifndef NO_SYS_NO_TIMERS
+#define NO_SYS_NO_TIMERS                0
+#endif
+
+/**
+ * MEMCPY: override this if you have a faster implementation at hand than the
+ * one included in your C library
+ */
+#ifndef MEMCPY
+#define MEMCPY(dst,src,len)             memcpy(dst,src,len)
+#endif
+
+/**
+ * SMEMCPY: override this with care! Some compilers (e.g. gcc) can inline a
+ * call to memcpy() if the length is known at compile time and is small.
+ */
+#ifndef SMEMCPY
+#define SMEMCPY(dst,src,len)            memcpy(dst,src,len)
+#endif
+
+/*
+   ------------------------------------
+   ---------- Memory options ----------
+   ------------------------------------
+*/
+/**
+ * MEM_LIBC_MALLOC==1: Use malloc/free/realloc provided by your C-library
+ * instead of the lwip internal allocator. Can save code size if you
+ * already use it.
+ */
+#ifndef MEM_LIBC_MALLOC
+#define MEM_LIBC_MALLOC                 0
+#endif
+
+/**
+* MEMP_MEM_MALLOC==1: Use mem_malloc/mem_free instead of the lwip pool allocator.
+* Especially useful with MEM_LIBC_MALLOC but handle with care regarding execution
+* speed and usage from interrupts!
+*/
+#ifndef MEMP_MEM_MALLOC
+#define MEMP_MEM_MALLOC                 0
+#endif
+
+/**
+ * MEM_ALIGNMENT: should be set to the alignment of the CPU
+ *    4 byte alignment -> #define MEM_ALIGNMENT 4
+ *    2 byte alignment -> #define MEM_ALIGNMENT 2
+ */
+#ifndef MEM_ALIGNMENT
+#define MEM_ALIGNMENT                   1
+#endif
+
+/**
+ * MEM_SIZE: the size of the heap memory. If the application will send
+ * a lot of data that needs to be copied, this should be set high.
+ */
+#ifndef MEM_SIZE
+#define MEM_SIZE                        1600
+#endif
+
+/**
+ * MEMP_SEPARATE_POOLS: if defined to 1, each pool is placed in its own array.
+ * This can be used to individually change the location of each pool.
+ * Default is one big array for all pools
+ */
+#ifndef MEMP_SEPARATE_POOLS
+#define MEMP_SEPARATE_POOLS             0
+#endif
+
+/**
+ * MEMP_OVERFLOW_CHECK: memp overflow protection reserves a configurable
+ * amount of bytes before and after each memp element in every pool and fills
+ * it with a prominent default value.
+ *    MEMP_OVERFLOW_CHECK == 0 no checking
+ *    MEMP_OVERFLOW_CHECK == 1 checks each element when it is freed
+ *    MEMP_OVERFLOW_CHECK >= 2 checks each element in every pool every time
+ *      memp_malloc() or memp_free() is called (useful but slow!)
+ */
+#ifndef MEMP_OVERFLOW_CHECK
+#define MEMP_OVERFLOW_CHECK             0
+#endif
+
+/**
+ * MEMP_SANITY_CHECK==1: run a sanity check after each memp_free() to make
+ * sure that there are no cycles in the linked lists.
+ */
+#ifndef MEMP_SANITY_CHECK
+#define MEMP_SANITY_CHECK               0
+#endif
+
+/**
+ * MEM_USE_POOLS==1: Use an alternative to malloc() by allocating from a set
+ * of memory pools of various sizes. When mem_malloc is called, an element of
+ * the smallest pool that can provide the length needed is returned.
+ * To use this, MEMP_USE_CUSTOM_POOLS also has to be enabled.
+ */
+#ifndef MEM_USE_POOLS
+#define MEM_USE_POOLS                   0
+#endif
+
+/**
+ * MEM_USE_POOLS_TRY_BIGGER_POOL==1: if one malloc-pool is empty, try the next
+ * bigger pool - WARNING: THIS MIGHT WASTE MEMORY but it can make a system more
+ * reliable. */
+#ifndef MEM_USE_POOLS_TRY_BIGGER_POOL
+#define MEM_USE_POOLS_TRY_BIGGER_POOL   0
+#endif
+
+/**
+ * MEMP_USE_CUSTOM_POOLS==1: whether to include a user file lwippools.h
+ * that defines additional pools beyond the "standard" ones required
+ * by lwIP. If you set this to 1, you must have lwippools.h in your 
+ * inlude path somewhere. 
+ */
+#ifndef MEMP_USE_CUSTOM_POOLS
+#define MEMP_USE_CUSTOM_POOLS           0
+#endif
+
+/**
+ * Set this to 1 if you want to free PBUF_RAM pbufs (or call mem_free()) from
+ * interrupt context (or another context that doesn't allow waiting for a
+ * semaphore).
+ * If set to 1, mem_malloc will be protected by a semaphore and SYS_ARCH_PROTECT,
+ * while mem_free will only use SYS_ARCH_PROTECT. mem_malloc SYS_ARCH_UNPROTECTs
+ * with each loop so that mem_free can run.
+ *
+ * ATTENTION: As you can see from the above description, this leads to dis-/
+ * enabling interrupts often, which can be slow! Also, on low memory, mem_malloc
+ * can need longer.
+ *
+ * If you don't want that, at least for NO_SYS=0, you can still use the following
+ * functions to enqueue a deallocation call which then runs in the tcpip_thread
+ * context:
+ * - pbuf_free_callback(p);
+ * - mem_free_callback(m);
+ */
+#ifndef LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
+#define LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT 0
+#endif
+
+/*
+   ------------------------------------------------
+   ---------- Internal Memory Pool Sizes ----------
+   ------------------------------------------------
+*/
+/**
+ * MEMP_NUM_PBUF: the number of memp struct pbufs (used for PBUF_ROM and PBUF_REF).
+ * If the application sends a lot of data out of ROM (or other static memory),
+ * this should be set high.
+ */
+#ifndef MEMP_NUM_PBUF
+#define MEMP_NUM_PBUF                   16
+#endif
+
+/**
+ * MEMP_NUM_RAW_PCB: Number of raw connection PCBs
+ * (requires the LWIP_RAW option)
+ */
+#ifndef MEMP_NUM_RAW_PCB
+#define MEMP_NUM_RAW_PCB                4
+#endif
+
+/**
+ * MEMP_NUM_UDP_PCB: the number of UDP protocol control blocks. One
+ * per active UDP "connection".
+ * (requires the LWIP_UDP option)
+ */
+#ifndef MEMP_NUM_UDP_PCB
+#define MEMP_NUM_UDP_PCB                4
+#endif
+
+/**
+ * MEMP_NUM_TCP_PCB: the number of simulatenously active TCP connections.
+ * (requires the LWIP_TCP option)
+ */
+#ifndef MEMP_NUM_TCP_PCB
+#define MEMP_NUM_TCP_PCB                5
+#endif
+
+/**
+ * MEMP_NUM_TCP_PCB_LISTEN: the number of listening TCP connections.
+ * (requires the LWIP_TCP option)
+ */
+#ifndef MEMP_NUM_TCP_PCB_LISTEN
+#define MEMP_NUM_TCP_PCB_LISTEN         8
+#endif
+
+/**
+ * MEMP_NUM_TCP_SEG: the number of simultaneously queued TCP segments.
+ * (requires the LWIP_TCP option)
+ */
+#ifndef MEMP_NUM_TCP_SEG
+#define MEMP_NUM_TCP_SEG                16
+#endif
+
+/**
+ * MEMP_NUM_REASSDATA: the number of IP packets simultaneously queued for
+ * reassembly (whole packets, not fragments!)
+ */
+#ifndef MEMP_NUM_REASSDATA
+#define MEMP_NUM_REASSDATA              5
+#endif
+
+/**
+ * MEMP_NUM_FRAG_PBUF: the number of IP fragments simultaneously sent
+ * (fragments, not whole packets!).
+ * This is only used with IP_FRAG_USES_STATIC_BUF==0 and
+ * LWIP_NETIF_TX_SINGLE_PBUF==0 and only has to be > 1 with DMA-enabled MACs
+ * where the packet is not yet sent when netif->output returns.
+ */
+#ifndef MEMP_NUM_FRAG_PBUF
+#define MEMP_NUM_FRAG_PBUF              15
+#endif
+
+/**
+ * MEMP_NUM_ARP_QUEUE: the number of simulateously queued outgoing
+ * packets (pbufs) that are waiting for an ARP request (to resolve
+ * their destination address) to finish.
+ * (requires the ARP_QUEUEING option)
+ */
+#ifndef MEMP_NUM_ARP_QUEUE
+#define MEMP_NUM_ARP_QUEUE              30
+#endif
+
+/**
+ * MEMP_NUM_IGMP_GROUP: The number of multicast groups whose network interfaces
+ * can be members et the same time (one per netif - allsystems group -, plus one
+ * per netif membership).
+ * (requires the LWIP_IGMP option)
+ */
+#ifndef MEMP_NUM_IGMP_GROUP
+#define MEMP_NUM_IGMP_GROUP             8
+#endif
+
+/**
+ * MEMP_NUM_SYS_TIMEOUT: the number of simulateously active timeouts.
+ * (requires NO_SYS==0)
+ */
+#ifndef MEMP_NUM_SYS_TIMEOUT
+#define MEMP_NUM_SYS_TIMEOUT            3
+#endif
+
+/**
+ * MEMP_NUM_NETBUF: the number of struct netbufs.
+ * (only needed if you use the sequential API, like api_lib.c)
+ */
+#ifndef MEMP_NUM_NETBUF
+#define MEMP_NUM_NETBUF                 2
+#endif
+
+/**
+ * MEMP_NUM_NETCONN: the number of struct netconns.
+ * (only needed if you use the sequential API, like api_lib.c)
+ */
+#ifndef MEMP_NUM_NETCONN
+#define MEMP_NUM_NETCONN                4
+#endif
+
+/**
+ * MEMP_NUM_TCPIP_MSG_API: the number of struct tcpip_msg, which are used
+ * for callback/timeout API communication. 
+ * (only needed if you use tcpip.c)
+ */
+#ifndef MEMP_NUM_TCPIP_MSG_API
+#define MEMP_NUM_TCPIP_MSG_API          8
+#endif
+
+/**
+ * MEMP_NUM_TCPIP_MSG_INPKT: the number of struct tcpip_msg, which are used
+ * for incoming packets. 
+ * (only needed if you use tcpip.c)
+ */
+#ifndef MEMP_NUM_TCPIP_MSG_INPKT
+#define MEMP_NUM_TCPIP_MSG_INPKT        8
+#endif
+
+/**
+ * MEMP_NUM_SNMP_NODE: the number of leafs in the SNMP tree.
+ */
+#ifndef MEMP_NUM_SNMP_NODE
+#define MEMP_NUM_SNMP_NODE              50
+#endif
+
+/**
+ * MEMP_NUM_SNMP_ROOTNODE: the number of branches in the SNMP tree.
+ * Every branch has one leaf (MEMP_NUM_SNMP_NODE) at least!
+ */
+#ifndef MEMP_NUM_SNMP_ROOTNODE
+#define MEMP_NUM_SNMP_ROOTNODE          30
+#endif
+
+/**
+ * MEMP_NUM_SNMP_VARBIND: the number of concurrent requests (does not have to
+ * be changed normally) - 2 of these are used per request (1 for input,
+ * 1 for output)
+ */
+#ifndef MEMP_NUM_SNMP_VARBIND
+#define MEMP_NUM_SNMP_VARBIND           2
+#endif
+
+/**
+ * MEMP_NUM_SNMP_VALUE: the number of OID or values concurrently used
+ * (does not have to be changed normally) - 3 of these are used per request
+ * (1 for the value read and 2 for OIDs - input and output)
+ */
+#ifndef MEMP_NUM_SNMP_VALUE
+#define MEMP_NUM_SNMP_VALUE             3
+#endif
+
+/**
+ * MEMP_NUM_NETDB: the number of concurrently running lwip_addrinfo() calls
+ * (before freeing the corresponding memory using lwip_freeaddrinfo()).
+ */
+#ifndef MEMP_NUM_NETDB
+#define MEMP_NUM_NETDB                  1
+#endif
+
+/**
+ * MEMP_NUM_LOCALHOSTLIST: the number of host entries in the local host list
+ * if DNS_LOCAL_HOSTLIST_IS_DYNAMIC==1.
+ */
+#ifndef MEMP_NUM_LOCALHOSTLIST
+#define MEMP_NUM_LOCALHOSTLIST          1
+#endif
+
+/**
+ * MEMP_NUM_PPPOE_INTERFACES: the number of concurrently active PPPoE
+ * interfaces (only used with PPPOE_SUPPORT==1)
+ */
+#ifndef MEMP_NUM_PPPOE_INTERFACES
+#define MEMP_NUM_PPPOE_INTERFACES       1
+#endif
+
+/**
+ * PBUF_POOL_SIZE: the number of buffers in the pbuf pool. 
+ */
+#ifndef PBUF_POOL_SIZE
+#define PBUF_POOL_SIZE                  16
+#endif
+
+/*
+   ---------------------------------
+   ---------- ARP options ----------
+   ---------------------------------
+*/
+/**
+ * LWIP_ARP==1: Enable ARP functionality.
+ */
+#ifndef LWIP_ARP
+#define LWIP_ARP                        1
+#endif
+
+/**
+ * ARP_TABLE_SIZE: Number of active MAC-IP address pairs cached.
+ */
+#ifndef ARP_TABLE_SIZE
+#define ARP_TABLE_SIZE                  10
+#endif
+
+/**
+ * ARP_QUEUEING==1: Outgoing packets are queued during hardware address
+ * resolution.
+ */
+#ifndef ARP_QUEUEING
+#define ARP_QUEUEING                    1
+#endif
+
+/**
+ * ETHARP_TRUST_IP_MAC==1: Incoming IP packets cause the ARP table to be
+ * updated with the source MAC and IP addresses supplied in the packet.
+ * You may want to disable this if you do not trust LAN peers to have the
+ * correct addresses, or as a limited approach to attempt to handle
+ * spoofing. If disabled, lwIP will need to make a new ARP request if
+ * the peer is not already in the ARP table, adding a little latency.
+ * The peer *is* in the ARP table if it requested our address before.
+ * Also notice that this slows down input processing of every IP packet!
+ */
+#ifndef ETHARP_TRUST_IP_MAC
+#define ETHARP_TRUST_IP_MAC             0
+#endif
+
+/**
+ * ETHARP_SUPPORT_VLAN==1: support receiving ethernet packets with VLAN header.
+ * Additionally, you can define ETHARP_VLAN_CHECK to an u16_t VLAN ID to check.
+ * If ETHARP_VLAN_CHECK is defined, only VLAN-traffic for this VLAN is accepted.
+ * If ETHARP_VLAN_CHECK is not defined, all traffic is accepted.
+ */
+#ifndef ETHARP_SUPPORT_VLAN
+#define ETHARP_SUPPORT_VLAN             0
+#endif
+
+/** LWIP_ETHERNET==1: enable ethernet support for PPPoE even though ARP
+ * might be disabled
+ */
+#ifndef LWIP_ETHERNET
+#define LWIP_ETHERNET                   (LWIP_ARP || PPPOE_SUPPORT)
+#endif
+
+/** ETH_PAD_SIZE: number of bytes added before the ethernet header to ensure
+ * alignment of payload after that header. Since the header is 14 bytes long,
+ * without this padding e.g. addresses in the IP header will not be aligned
+ * on a 32-bit boundary, so setting this to 2 can speed up 32-bit-platforms.
+ */
+#ifndef ETH_PAD_SIZE
+#define ETH_PAD_SIZE                    0
+#endif
+
+/** ETHARP_SUPPORT_STATIC_ENTRIES==1: enable code to support static ARP table
+ * entries (using etharp_add_static_entry/etharp_remove_static_entry).
+ */
+#ifndef ETHARP_SUPPORT_STATIC_ENTRIES
+#define ETHARP_SUPPORT_STATIC_ENTRIES   0
+#endif
+
+
+/*
+   --------------------------------
+   ---------- IP options ----------
+   --------------------------------
+*/
+/**
+ * IP_FORWARD==1: Enables the ability to forward IP packets across network
+ * interfaces. If you are going to run lwIP on a device with only one network
+ * interface, define this to 0.
+ */
+#ifndef IP_FORWARD
+#define IP_FORWARD                      0
+#endif
+
+/**
+ * IP_OPTIONS_ALLOWED: Defines the behavior for IP options.
+ *      IP_OPTIONS_ALLOWED==0: All packets with IP options are dropped.
+ *      IP_OPTIONS_ALLOWED==1: IP options are allowed (but not parsed).
+ */
+#ifndef IP_OPTIONS_ALLOWED
+#define IP_OPTIONS_ALLOWED              1
+#endif
+
+/**
+ * IP_REASSEMBLY==1: Reassemble incoming fragmented IP packets. Note that
+ * this option does not affect outgoing packet sizes, which can be controlled
+ * via IP_FRAG.
+ */
+#ifndef IP_REASSEMBLY
+#define IP_REASSEMBLY                   1
+#endif
+
+/**
+ * IP_FRAG==1: Fragment outgoing IP packets if their size exceeds MTU. Note
+ * that this option does not affect incoming packet sizes, which can be
+ * controlled via IP_REASSEMBLY.
+ */
+#ifndef IP_FRAG
+#define IP_FRAG                         1
+#endif
+
+/**
+ * IP_REASS_MAXAGE: Maximum time (in multiples of IP_TMR_INTERVAL - so seconds, normally)
+ * a fragmented IP packet waits for all fragments to arrive. If not all fragments arrived
+ * in this time, the whole packet is discarded.
+ */
+#ifndef IP_REASS_MAXAGE
+#define IP_REASS_MAXAGE                 3
+#endif
+
+/**
+ * IP_REASS_MAX_PBUFS: Total maximum amount of pbufs waiting to be reassembled.
+ * Since the received pbufs are enqueued, be sure to configure
+ * PBUF_POOL_SIZE > IP_REASS_MAX_PBUFS so that the stack is still able to receive
+ * packets even if the maximum amount of fragments is enqueued for reassembly!
+ */
+#ifndef IP_REASS_MAX_PBUFS
+#define IP_REASS_MAX_PBUFS              10
+#endif
+
+/**
+ * IP_FRAG_USES_STATIC_BUF==1: Use a static MTU-sized buffer for IP
+ * fragmentation. Otherwise pbufs are allocated and reference the original
+ * packet data to be fragmented (or with LWIP_NETIF_TX_SINGLE_PBUF==1,
+ * new PBUF_RAM pbufs are used for fragments).
+ * ATTENTION: IP_FRAG_USES_STATIC_BUF==1 may not be used for DMA-enabled MACs!
+ */
+#ifndef IP_FRAG_USES_STATIC_BUF
+#define IP_FRAG_USES_STATIC_BUF         0
+#endif
+
+/**
+ * IP_FRAG_MAX_MTU: Assumed max MTU on any interface for IP frag buffer
+ * (requires IP_FRAG_USES_STATIC_BUF==1)
+ */
+#if IP_FRAG_USES_STATIC_BUF && !defined(IP_FRAG_MAX_MTU)
+#define IP_FRAG_MAX_MTU                 1500
+#endif
+
+/**
+ * IP_DEFAULT_TTL: Default value for Time-To-Live used by transport layers.
+ */
+#ifndef IP_DEFAULT_TTL
+#define IP_DEFAULT_TTL                  255
+#endif
+
+/**
+ * IP_SOF_BROADCAST=1: Use the SOF_BROADCAST field to enable broadcast
+ * filter per pcb on udp and raw send operations. To enable broadcast filter
+ * on recv operations, you also have to set IP_SOF_BROADCAST_RECV=1.
+ */
+#ifndef IP_SOF_BROADCAST
+#define IP_SOF_BROADCAST                0
+#endif
+
+/**
+ * IP_SOF_BROADCAST_RECV (requires IP_SOF_BROADCAST=1) enable the broadcast
+ * filter on recv operations.
+ */
+#ifndef IP_SOF_BROADCAST_RECV
+#define IP_SOF_BROADCAST_RECV           0
+#endif
+
+/*
+   ----------------------------------
+   ---------- ICMP options ----------
+   ----------------------------------
+*/
+/**
+ * LWIP_ICMP==1: Enable ICMP module inside the IP stack.
+ * Be careful, disable that make your product non-compliant to RFC1122
+ */
+#ifndef LWIP_ICMP
+#define LWIP_ICMP                       1
+#endif
+
+/**
+ * ICMP_TTL: Default value for Time-To-Live used by ICMP packets.
+ */
+#ifndef ICMP_TTL
+#define ICMP_TTL                       (IP_DEFAULT_TTL)
+#endif
+
+/**
+ * LWIP_BROADCAST_PING==1: respond to broadcast pings (default is unicast only)
+ */
+#ifndef LWIP_BROADCAST_PING
+#define LWIP_BROADCAST_PING             0
+#endif
+
+/**
+ * LWIP_MULTICAST_PING==1: respond to multicast pings (default is unicast only)
+ */
+#ifndef LWIP_MULTICAST_PING
+#define LWIP_MULTICAST_PING             0
+#endif
+
+/*
+   ---------------------------------
+   ---------- RAW options ----------
+   ---------------------------------
+*/
+/**
+ * LWIP_RAW==1: Enable application layer to hook into the IP layer itself.
+ */
+#ifndef LWIP_RAW
+#define LWIP_RAW                        1
+#endif
+
+/**
+ * LWIP_RAW==1: Enable application layer to hook into the IP layer itself.
+ */
+#ifndef RAW_TTL
+#define RAW_TTL                        (IP_DEFAULT_TTL)
+#endif
+
+/*
+   ----------------------------------
+   ---------- DHCP options ----------
+   ----------------------------------
+*/
+/**
+ * LWIP_DHCP==1: Enable DHCP module.
+ */
+#ifndef LWIP_DHCP
+#define LWIP_DHCP                       0
+#endif
+
+/**
+ * DHCP_DOES_ARP_CHECK==1: Do an ARP check on the offered address.
+ */
+#ifndef DHCP_DOES_ARP_CHECK
+#define DHCP_DOES_ARP_CHECK             ((LWIP_DHCP) && (LWIP_ARP))
+#endif
+
+/*
+   ------------------------------------
+   ---------- AUTOIP options ----------
+   ------------------------------------
+*/
+/**
+ * LWIP_AUTOIP==1: Enable AUTOIP module.
+ */
+#ifndef LWIP_AUTOIP
+#define LWIP_AUTOIP                     0
+#endif
+
+/**
+ * LWIP_DHCP_AUTOIP_COOP==1: Allow DHCP and AUTOIP to be both enabled on
+ * the same interface at the same time.
+ */
+#ifndef LWIP_DHCP_AUTOIP_COOP
+#define LWIP_DHCP_AUTOIP_COOP           0
+#endif
+
+/**
+ * LWIP_DHCP_AUTOIP_COOP_TRIES: Set to the number of DHCP DISCOVER probes
+ * that should be sent before falling back on AUTOIP. This can be set
+ * as low as 1 to get an AutoIP address very quickly, but you should
+ * be prepared to handle a changing IP address when DHCP overrides
+ * AutoIP.
+ */
+#ifndef LWIP_DHCP_AUTOIP_COOP_TRIES
+#define LWIP_DHCP_AUTOIP_COOP_TRIES     9
+#endif
+
+/*
+   ----------------------------------
+   ---------- SNMP options ----------
+   ----------------------------------
+*/
+/**
+ * LWIP_SNMP==1: Turn on SNMP module. UDP must be available for SNMP
+ * transport.
+ */
+#ifndef LWIP_SNMP
+#define LWIP_SNMP                       0
+#endif
+
+/**
+ * SNMP_CONCURRENT_REQUESTS: Number of concurrent requests the module will
+ * allow. At least one request buffer is required.
+ * Does not have to be changed unless external MIBs answer request asynchronously
+ */
+#ifndef SNMP_CONCURRENT_REQUESTS
+#define SNMP_CONCURRENT_REQUESTS        1
+#endif
+
+/**
+ * SNMP_TRAP_DESTINATIONS: Number of trap destinations. At least one trap
+ * destination is required
+ */
+#ifndef SNMP_TRAP_DESTINATIONS
+#define SNMP_TRAP_DESTINATIONS          1
+#endif
+
+/**
+ * SNMP_PRIVATE_MIB: 
+ * When using a private MIB, you have to create a file 'private_mib.h' that contains
+ * a 'struct mib_array_node mib_private' which contains your MIB.
+ */
+#ifndef SNMP_PRIVATE_MIB
+#define SNMP_PRIVATE_MIB                0
+#endif
+
+/**
+ * Only allow SNMP write actions that are 'safe' (e.g. disabeling netifs is not
+ * a safe action and disabled when SNMP_SAFE_REQUESTS = 1).
+ * Unsafe requests are disabled by default!
+ */
+#ifndef SNMP_SAFE_REQUESTS
+#define SNMP_SAFE_REQUESTS              1
+#endif
+
+/**
+ * The maximum length of strings used. This affects the size of
+ * MEMP_SNMP_VALUE elements.
+ */
+#ifndef SNMP_MAX_OCTET_STRING_LEN
+#define SNMP_MAX_OCTET_STRING_LEN       127
+#endif
+
+/**
+ * The maximum depth of the SNMP tree.
+ * With private MIBs enabled, this depends on your MIB!
+ * This affects the size of MEMP_SNMP_VALUE elements.
+ */
+#ifndef SNMP_MAX_TREE_DEPTH
+#define SNMP_MAX_TREE_DEPTH             15
+#endif
+
+/**
+ * The size of the MEMP_SNMP_VALUE elements, normally calculated from
+ * SNMP_MAX_OCTET_STRING_LEN and SNMP_MAX_TREE_DEPTH.
+ */
+#ifndef SNMP_MAX_VALUE_SIZE
+#define SNMP_MAX_VALUE_SIZE             LWIP_MAX((SNMP_MAX_OCTET_STRING_LEN)+1, sizeof(s32_t)*(SNMP_MAX_TREE_DEPTH))
+#endif
+
+/*
+   ----------------------------------
+   ---------- IGMP options ----------
+   ----------------------------------
+*/
+/**
+ * LWIP_IGMP==1: Turn on IGMP module. 
+ */
+#ifndef LWIP_IGMP
+#define LWIP_IGMP                       0
+#endif
+
+/*
+   ----------------------------------
+   ---------- DNS options -----------
+   ----------------------------------
+*/
+/**
+ * LWIP_DNS==1: Turn on DNS module. UDP must be available for DNS
+ * transport.
+ */
+#ifndef LWIP_DNS
+#define LWIP_DNS                        0
+#endif
+
+/** DNS maximum number of entries to maintain locally. */
+#ifndef DNS_TABLE_SIZE
+#define DNS_TABLE_SIZE                  4
+#endif
+
+/** DNS maximum host name length supported in the name table. */
+#ifndef DNS_MAX_NAME_LENGTH
+#define DNS_MAX_NAME_LENGTH             256
+#endif
+
+/** The maximum of DNS servers */
+#ifndef DNS_MAX_SERVERS
+#define DNS_MAX_SERVERS                 2
+#endif
+
+/** DNS do a name checking between the query and the response. */
+#ifndef DNS_DOES_NAME_CHECK
+#define DNS_DOES_NAME_CHECK             1
+#endif
+
+/** DNS message max. size. Default value is RFC compliant. */
+#ifndef DNS_MSG_SIZE
+#define DNS_MSG_SIZE                    512
+#endif
+
+/** DNS_LOCAL_HOSTLIST: Implements a local host-to-address list. If enabled,
+ *  you have to define
+ *    #define DNS_LOCAL_HOSTLIST_INIT {{"host1", 0x123}, {"host2", 0x234}}
+ *  (an array of structs name/address, where address is an u32_t in network
+ *  byte order).
+ *
+ *  Instead, you can also use an external function:
+ *  #define DNS_LOOKUP_LOCAL_EXTERN(x) extern u32_t my_lookup_function(const char *name)
+ *  that returns the IP address or INADDR_NONE if not found.
+ */
+#ifndef DNS_LOCAL_HOSTLIST
+#define DNS_LOCAL_HOSTLIST              0
+#endif /* DNS_LOCAL_HOSTLIST */
+
+/** If this is turned on, the local host-list can be dynamically changed
+ *  at runtime. */
+#ifndef DNS_LOCAL_HOSTLIST_IS_DYNAMIC
+#define DNS_LOCAL_HOSTLIST_IS_DYNAMIC   0
+#endif /* DNS_LOCAL_HOSTLIST_IS_DYNAMIC */
+
+/*
+   ---------------------------------
+   ---------- UDP options ----------
+   ---------------------------------
+*/
+/**
+ * LWIP_UDP==1: Turn on UDP.
+ */
+#ifndef LWIP_UDP
+#define LWIP_UDP                        1
+#endif
+
+/**
+ * LWIP_UDPLITE==1: Turn on UDP-Lite. (Requires LWIP_UDP)
+ */
+#ifndef LWIP_UDPLITE
+#define LWIP_UDPLITE                    0
+#endif
+
+/**
+ * UDP_TTL: Default Time-To-Live value.
+ */
+#ifndef UDP_TTL
+#define UDP_TTL                         (IP_DEFAULT_TTL)
+#endif
+
+/**
+ * LWIP_NETBUF_RECVINFO==1: append destination addr and port to every netbuf.
+ */
+#ifndef LWIP_NETBUF_RECVINFO
+#define LWIP_NETBUF_RECVINFO            0
+#endif
+
+/*
+   ---------------------------------
+   ---------- TCP options ----------
+   ---------------------------------
+*/
+/**
+ * LWIP_TCP==1: Turn on TCP.
+ */
+#ifndef LWIP_TCP
+#define LWIP_TCP                        1
+#endif
+
+/**
+ * TCP_TTL: Default Time-To-Live value.
+ */
+#ifndef TCP_TTL
+#define TCP_TTL                         (IP_DEFAULT_TTL)
+#endif
+
+/**
+ * TCP_WND: The size of a TCP window.  This must be at least 
+ * (2 * TCP_MSS) for things to work well
+ */
+#ifndef TCP_WND
+#define TCP_WND                         (4 * TCP_MSS)
+#endif 
+
+/**
+ * TCP_MAXRTX: Maximum number of retransmissions of data segments.
+ */
+#ifndef TCP_MAXRTX
+#define TCP_MAXRTX                      12
+#endif
+
+/**
+ * TCP_SYNMAXRTX: Maximum number of retransmissions of SYN segments.
+ */
+#ifndef TCP_SYNMAXRTX
+#define TCP_SYNMAXRTX                   6
+#endif
+
+/**
+ * TCP_QUEUE_OOSEQ==1: TCP will queue segments that arrive out of order.
+ * Define to 0 if your device is low on memory.
+ */
+#ifndef TCP_QUEUE_OOSEQ
+#define TCP_QUEUE_OOSEQ                 (LWIP_TCP)
+#endif
+
+/**
+ * TCP_MSS: TCP Maximum segment size. (default is 536, a conservative default,
+ * you might want to increase this.)
+ * For the receive side, this MSS is advertised to the remote side
+ * when opening a connection. For the transmit size, this MSS sets
+ * an upper limit on the MSS advertised by the remote host.
+ */
+#ifndef TCP_MSS
+#define TCP_MSS                         536
+#endif
+
+/**
+ * TCP_CALCULATE_EFF_SEND_MSS: "The maximum size of a segment that TCP really
+ * sends, the 'effective send MSS,' MUST be the smaller of the send MSS (which
+ * reflects the available reassembly buffer size at the remote host) and the
+ * largest size permitted by the IP layer" (RFC 1122)
+ * Setting this to 1 enables code that checks TCP_MSS against the MTU of the
+ * netif used for a connection and limits the MSS if it would be too big otherwise.
+ */
+#ifndef TCP_CALCULATE_EFF_SEND_MSS
+#define TCP_CALCULATE_EFF_SEND_MSS      1
+#endif
+
+
+/**
+ * TCP_SND_BUF: TCP sender buffer space (bytes). 
+ */
+#ifndef TCP_SND_BUF
+#define TCP_SND_BUF                     256
+#endif
+
+/**
+ * TCP_SND_QUEUELEN: TCP sender buffer space (pbufs). This must be at least
+ * as much as (2 * TCP_SND_BUF/TCP_MSS) for things to work.
+ */
+#ifndef TCP_SND_QUEUELEN
+#define TCP_SND_QUEUELEN                (4 * (TCP_SND_BUF)/(TCP_MSS))
+#endif
+
+/**
+ * TCP_SNDLOWAT: TCP writable space (bytes). This must be less than
+ * TCP_SND_BUF. It is the amount of space which must be available in the
+ * TCP snd_buf for select to return writable (combined with TCP_SNDQUEUELOWAT).
+ */
+#ifndef TCP_SNDLOWAT
+#define TCP_SNDLOWAT                    ((TCP_SND_BUF)/2)
+#endif
+
+/**
+ * TCP_SNDQUEUELOWAT: TCP writable bufs (pbuf count). This must be grater
+ * than TCP_SND_QUEUELEN. If the number of pbufs queued on a pcb drops below
+ * this number, select returns writable (combined with TCP_SNDLOWAT).
+ */
+#ifndef TCP_SNDQUEUELOWAT
+#define TCP_SNDQUEUELOWAT               ((TCP_SND_QUEUELEN)/2)
+#endif
+
+/**
+ * TCP_LISTEN_BACKLOG: Enable the backlog option for tcp listen pcb.
+ */
+#ifndef TCP_LISTEN_BACKLOG
+#define TCP_LISTEN_BACKLOG              0
+#endif
+
+/**
+ * The maximum allowed backlog for TCP listen netconns.
+ * This backlog is used unless another is explicitly specified.
+ * 0xff is the maximum (u8_t).
+ */
+#ifndef TCP_DEFAULT_LISTEN_BACKLOG
+#define TCP_DEFAULT_LISTEN_BACKLOG      0xff
+#endif
+
+/**
+ * TCP_OVERSIZE: The maximum number of bytes that tcp_write may
+ * allocate ahead of time in an attempt to create shorter pbuf chains
+ * for transmission. The meaningful range is 0 to TCP_MSS. Some
+ * suggested values are:
+ *
+ * 0:         Disable oversized allocation. Each tcp_write() allocates a new
+              pbuf (old behaviour).
+ * 1:         Allocate size-aligned pbufs with minimal excess. Use this if your
+ *            scatter-gather DMA requires aligned fragments.
+ * 128:       Limit the pbuf/memory overhead to 20%.
+ * TCP_MSS:   Try to create unfragmented TCP packets.
+ * TCP_MSS/4: Try to create 4 fragments or less per TCP packet.
+ */
+#ifndef TCP_OVERSIZE
+#define TCP_OVERSIZE                    TCP_MSS
+#endif
+
+/**
+ * LWIP_TCP_TIMESTAMPS==1: support the TCP timestamp option.
+ */
+#ifndef LWIP_TCP_TIMESTAMPS
+#define LWIP_TCP_TIMESTAMPS             0
+#endif
+
+/**
+ * TCP_WND_UPDATE_THRESHOLD: difference in window to trigger an
+ * explicit window update
+ */
+#ifndef TCP_WND_UPDATE_THRESHOLD
+#define TCP_WND_UPDATE_THRESHOLD   (TCP_WND / 4)
+#endif
+
+/**
+ * LWIP_EVENT_API and LWIP_CALLBACK_API: Only one of these should be set to 1.
+ *     LWIP_EVENT_API==1: The user defines lwip_tcp_event() to receive all
+ *         events (accept, sent, etc) that happen in the system.
+ *     LWIP_CALLBACK_API==1: The PCB callback function is called directly
+ *         for the event.
+ */
+#ifndef LWIP_EVENT_API
+#define LWIP_EVENT_API                  0
+#define LWIP_CALLBACK_API               1
+#else 
+#define LWIP_EVENT_API                  1
+#define LWIP_CALLBACK_API               0
+#endif
+
+
+/*
+   ----------------------------------
+   ---------- Pbuf options ----------
+   ----------------------------------
+*/
+/**
+ * PBUF_LINK_HLEN: the number of bytes that should be allocated for a
+ * link level header. The default is 14, the standard value for
+ * Ethernet.
+ */
+#ifndef PBUF_LINK_HLEN
+#define PBUF_LINK_HLEN                  (14 + ETH_PAD_SIZE)
+#endif
+
+/**
+ * PBUF_POOL_BUFSIZE: the size of each pbuf in the pbuf pool. The default is
+ * designed to accomodate single full size TCP frame in one pbuf, including
+ * TCP_MSS, IP header, and link header.
+ */
+#ifndef PBUF_POOL_BUFSIZE
+#define PBUF_POOL_BUFSIZE               LWIP_MEM_ALIGN_SIZE(TCP_MSS+40+PBUF_LINK_HLEN)
+#endif
+
+/*
+   ------------------------------------------------
+   ---------- Network Interfaces options ----------
+   ------------------------------------------------
+*/
+/**
+ * LWIP_NETIF_HOSTNAME==1: use DHCP_OPTION_HOSTNAME with netif's hostname
+ * field.
+ */
+#ifndef LWIP_NETIF_HOSTNAME
+#define LWIP_NETIF_HOSTNAME             0
+#endif
+
+/**
+ * LWIP_NETIF_API==1: Support netif api (in netifapi.c)
+ */
+#ifndef LWIP_NETIF_API
+#define LWIP_NETIF_API                  0
+#endif
+
+/**
+ * LWIP_NETIF_STATUS_CALLBACK==1: Support a callback function whenever an interface
+ * changes its up/down status (i.e., due to DHCP IP acquistion)
+ */
+#ifndef LWIP_NETIF_STATUS_CALLBACK
+#define LWIP_NETIF_STATUS_CALLBACK      0
+#endif
+
+/**
+ * LWIP_NETIF_LINK_CALLBACK==1: Support a callback function from an interface
+ * whenever the link changes (i.e., link down)
+ */
+#ifndef LWIP_NETIF_LINK_CALLBACK
+#define LWIP_NETIF_LINK_CALLBACK        0
+#endif
+
+/**
+ * LWIP_NETIF_HWADDRHINT==1: Cache link-layer-address hints (e.g. table
+ * indices) in struct netif. TCP and UDP can make use of this to prevent
+ * scanning the ARP table for every sent packet. While this is faster for big
+ * ARP tables or many concurrent connections, it might be counterproductive
+ * if you have a tiny ARP table or if there never are concurrent connections.
+ */
+#ifndef LWIP_NETIF_HWADDRHINT
+#define LWIP_NETIF_HWADDRHINT           0
+#endif
+
+/**
+ * LWIP_NETIF_LOOPBACK==1: Support sending packets with a destination IP
+ * address equal to the netif IP address, looping them back up the stack.
+ */
+#ifndef LWIP_NETIF_LOOPBACK
+#define LWIP_NETIF_LOOPBACK             0
+#endif
+
+/**
+ * LWIP_LOOPBACK_MAX_PBUFS: Maximum number of pbufs on queue for loopback
+ * sending for each netif (0 = disabled)
+ */
+#ifndef LWIP_LOOPBACK_MAX_PBUFS
+#define LWIP_LOOPBACK_MAX_PBUFS         0
+#endif
+
+/**
+ * LWIP_NETIF_LOOPBACK_MULTITHREADING: Indicates whether threading is enabled in
+ * the system, as netifs must change how they behave depending on this setting
+ * for the LWIP_NETIF_LOOPBACK option to work.
+ * Setting this is needed to avoid reentering non-reentrant functions like
+ * tcp_input().
+ *    LWIP_NETIF_LOOPBACK_MULTITHREADING==1: Indicates that the user is using a
+ *       multithreaded environment like tcpip.c. In this case, netif->input()
+ *       is called directly.
+ *    LWIP_NETIF_LOOPBACK_MULTITHREADING==0: Indicates a polling (or NO_SYS) setup.
+ *       The packets are put on a list and netif_poll() must be called in
+ *       the main application loop.
+ */
+#ifndef LWIP_NETIF_LOOPBACK_MULTITHREADING
+#define LWIP_NETIF_LOOPBACK_MULTITHREADING    (!NO_SYS)
+#endif
+
+/**
+ * LWIP_NETIF_TX_SINGLE_PBUF: if this is set to 1, lwIP tries to put all data
+ * to be sent into one single pbuf. This is for compatibility with DMA-enabled
+ * MACs that do not support scatter-gather.
+ * Beware that this might involve CPU-memcpy before transmitting that would not
+ * be needed without this flag! Use this only if you need to!
+ *
+ * @todo: TCP and IP-frag do not work with this, yet:
+ */
+#ifndef LWIP_NETIF_TX_SINGLE_PBUF
+#define LWIP_NETIF_TX_SINGLE_PBUF             0
+#endif /* LWIP_NETIF_TX_SINGLE_PBUF */
+
+/*
+   ------------------------------------
+   ---------- LOOPIF options ----------
+   ------------------------------------
+*/
+/**
+ * LWIP_HAVE_LOOPIF==1: Support loop interface (127.0.0.1) and loopif.c
+ */
+#ifndef LWIP_HAVE_LOOPIF
+#define LWIP_HAVE_LOOPIF                0
+#endif
+
+/*
+   ------------------------------------
+   ---------- SLIPIF options ----------
+   ------------------------------------
+*/
+/**
+ * LWIP_HAVE_SLIPIF==1: Support slip interface and slipif.c
+ */
+#ifndef LWIP_HAVE_SLIPIF
+#define LWIP_HAVE_SLIPIF                0
+#endif
+
+/*
+   ------------------------------------
+   ---------- Thread options ----------
+   ------------------------------------
+*/
+/**
+ * TCPIP_THREAD_NAME: The name assigned to the main tcpip thread.
+ */
+#ifndef TCPIP_THREAD_NAME
+#define TCPIP_THREAD_NAME              "tcpip_thread"
+#endif
+
+/**
+ * TCPIP_THREAD_STACKSIZE: The stack size used by the main tcpip thread.
+ * The stack size value itself is platform-dependent, but is passed to
+ * sys_thread_new() when the thread is created.
+ */
+#ifndef TCPIP_THREAD_STACKSIZE
+#define TCPIP_THREAD_STACKSIZE          0
+#endif
+
+/**
+ * TCPIP_THREAD_PRIO: The priority assigned to the main tcpip thread.
+ * The priority value itself is platform-dependent, but is passed to
+ * sys_thread_new() when the thread is created.
+ */
+#ifndef TCPIP_THREAD_PRIO
+#define TCPIP_THREAD_PRIO               1
+#endif
+
+/**
+ * TCPIP_MBOX_SIZE: The mailbox size for the tcpip thread messages
+ * The queue size value itself is platform-dependent, but is passed to
+ * sys_mbox_new() when tcpip_init is called.
+ */
+#ifndef TCPIP_MBOX_SIZE
+#define TCPIP_MBOX_SIZE                 0
+#endif
+
+/**
+ * SLIPIF_THREAD_NAME: The name assigned to the slipif_loop thread.
+ */
+#ifndef SLIPIF_THREAD_NAME
+#define SLIPIF_THREAD_NAME             "slipif_loop"
+#endif
+
+/**
+ * SLIP_THREAD_STACKSIZE: The stack size used by the slipif_loop thread.
+ * The stack size value itself is platform-dependent, but is passed to
+ * sys_thread_new() when the thread is created.
+ */
+#ifndef SLIPIF_THREAD_STACKSIZE
+#define SLIPIF_THREAD_STACKSIZE         0
+#endif
+
+/**
+ * SLIPIF_THREAD_PRIO: The priority assigned to the slipif_loop thread.
+ * The priority value itself is platform-dependent, but is passed to
+ * sys_thread_new() when the thread is created.
+ */
+#ifndef SLIPIF_THREAD_PRIO
+#define SLIPIF_THREAD_PRIO              1
+#endif
+
+/**
+ * PPP_THREAD_NAME: The name assigned to the pppInputThread.
+ */
+#ifndef PPP_THREAD_NAME
+#define PPP_THREAD_NAME                "pppInputThread"
+#endif
+
+/**
+ * PPP_THREAD_STACKSIZE: The stack size used by the pppInputThread.
+ * The stack size value itself is platform-dependent, but is passed to
+ * sys_thread_new() when the thread is created.
+ */
+#ifndef PPP_THREAD_STACKSIZE
+#define PPP_THREAD_STACKSIZE            0
+#endif
+
+/**
+ * PPP_THREAD_PRIO: The priority assigned to the pppInputThread.
+ * The priority value itself is platform-dependent, but is passed to
+ * sys_thread_new() when the thread is created.
+ */
+#ifndef PPP_THREAD_PRIO
+#define PPP_THREAD_PRIO                 1
+#endif
+
+/**
+ * DEFAULT_THREAD_NAME: The name assigned to any other lwIP thread.
+ */
+#ifndef DEFAULT_THREAD_NAME
+#define DEFAULT_THREAD_NAME            "lwIP"
+#endif
+
+/**
+ * DEFAULT_THREAD_STACKSIZE: The stack size used by any other lwIP thread.
+ * The stack size value itself is platform-dependent, but is passed to
+ * sys_thread_new() when the thread is created.
+ */
+#ifndef DEFAULT_THREAD_STACKSIZE
+#define DEFAULT_THREAD_STACKSIZE        0
+#endif
+
+/**
+ * DEFAULT_THREAD_PRIO: The priority assigned to any other lwIP thread.
+ * The priority value itself is platform-dependent, but is passed to
+ * sys_thread_new() when the thread is created.
+ */
+#ifndef DEFAULT_THREAD_PRIO
+#define DEFAULT_THREAD_PRIO             1
+#endif
+
+/**
+ * DEFAULT_RAW_RECVMBOX_SIZE: The mailbox size for the incoming packets on a
+ * NETCONN_RAW. The queue size value itself is platform-dependent, but is passed
+ * to sys_mbox_new() when the recvmbox is created.
+ */
+#ifndef DEFAULT_RAW_RECVMBOX_SIZE
+#define DEFAULT_RAW_RECVMBOX_SIZE       0
+#endif
+
+/**
+ * DEFAULT_UDP_RECVMBOX_SIZE: The mailbox size for the incoming packets on a
+ * NETCONN_UDP. The queue size value itself is platform-dependent, but is passed
+ * to sys_mbox_new() when the recvmbox is created.
+ */
+#ifndef DEFAULT_UDP_RECVMBOX_SIZE
+#define DEFAULT_UDP_RECVMBOX_SIZE       0
+#endif
+
+/**
+ * DEFAULT_TCP_RECVMBOX_SIZE: The mailbox size for the incoming packets on a
+ * NETCONN_TCP. The queue size value itself is platform-dependent, but is passed
+ * to sys_mbox_new() when the recvmbox is created.
+ */
+#ifndef DEFAULT_TCP_RECVMBOX_SIZE
+#define DEFAULT_TCP_RECVMBOX_SIZE       0
+#endif
+
+/**
+ * DEFAULT_ACCEPTMBOX_SIZE: The mailbox size for the incoming connections.
+ * The queue size value itself is platform-dependent, but is passed to
+ * sys_mbox_new() when the acceptmbox is created.
+ */
+#ifndef DEFAULT_ACCEPTMBOX_SIZE
+#define DEFAULT_ACCEPTMBOX_SIZE         0
+#endif
+
+/*
+   ----------------------------------------------
+   ---------- Sequential layer options ----------
+   ----------------------------------------------
+*/
+/**
+ * LWIP_TCPIP_CORE_LOCKING: (EXPERIMENTAL!)
+ * Don't use it if you're not an active lwIP project member
+ */
+#ifndef LWIP_TCPIP_CORE_LOCKING
+#define LWIP_TCPIP_CORE_LOCKING         0
+#endif
+
+/**
+ * LWIP_TCPIP_CORE_LOCKING_INPUT: (EXPERIMENTAL!)
+ * Don't use it if you're not an active lwIP project member
+ */
+#ifndef LWIP_TCPIP_CORE_LOCKING_INPUT
+#define LWIP_TCPIP_CORE_LOCKING_INPUT   0
+#endif
+
+/**
+ * LWIP_NETCONN==1: Enable Netconn API (require to use api_lib.c)
+ */
+#ifndef LWIP_NETCONN
+#define LWIP_NETCONN                    1
+#endif
+
+/** LWIP_TCPIP_TIMEOUT==1: Enable tcpip_timeout/tcpip_untimeout tod create
+ * timers running in tcpip_thread from another thread.
+ */
+#ifndef LWIP_TCPIP_TIMEOUT
+#define LWIP_TCPIP_TIMEOUT              1
+#endif
+
+/*
+   ------------------------------------
+   ---------- Socket options ----------
+   ------------------------------------
+*/
+/**
+ * LWIP_SOCKET==1: Enable Socket API (require to use sockets.c)
+ */
+#ifndef LWIP_SOCKET
+#define LWIP_SOCKET                     1
+#endif
+
+/**
+ * LWIP_COMPAT_SOCKETS==1: Enable BSD-style sockets functions names.
+ * (only used if you use sockets.c)
+ */
+#ifndef LWIP_COMPAT_SOCKETS
+#define LWIP_COMPAT_SOCKETS             1
+#endif
+
+/**
+ * LWIP_POSIX_SOCKETS_IO_NAMES==1: Enable POSIX-style sockets functions names.
+ * Disable this option if you use a POSIX operating system that uses the same
+ * names (read, write & close). (only used if you use sockets.c)
+ */
+#ifndef LWIP_POSIX_SOCKETS_IO_NAMES
+#define LWIP_POSIX_SOCKETS_IO_NAMES     1
+#endif
+
+/**
+ * LWIP_TCP_KEEPALIVE==1: Enable TCP_KEEPIDLE, TCP_KEEPINTVL and TCP_KEEPCNT
+ * options processing. Note that TCP_KEEPIDLE and TCP_KEEPINTVL have to be set
+ * in seconds. (does not require sockets.c, and will affect tcp.c)
+ */
+#ifndef LWIP_TCP_KEEPALIVE
+#define LWIP_TCP_KEEPALIVE              0
+#endif
+
+/**
+ * LWIP_SO_RCVTIMEO==1: Enable SO_RCVTIMEO processing.
+ */
+#ifndef LWIP_SO_RCVTIMEO
+#define LWIP_SO_RCVTIMEO                0
+#endif
+
+/**
+ * LWIP_SO_RCVBUF==1: Enable SO_RCVBUF processing.
+ */
+#ifndef LWIP_SO_RCVBUF
+#define LWIP_SO_RCVBUF                  0
+#endif
+
+/**
+ * If LWIP_SO_RCVBUF is used, this is the default value for recv_bufsize.
+ */
+#ifndef RECV_BUFSIZE_DEFAULT
+#define RECV_BUFSIZE_DEFAULT            INT_MAX
+#endif
+
+/**
+ * SO_REUSE==1: Enable SO_REUSEADDR option.
+ */
+#ifndef SO_REUSE
+#define SO_REUSE                        0
+#endif
+
+/**
+ * SO_REUSE_RXTOALL==1: Pass a copy of incoming broadcast/multicast packets
+ * to all local matches if SO_REUSEADDR is turned on.
+ * WARNING: Adds a memcpy for every packet if passing to more than one pcb!
+ */
+#ifndef SO_REUSE_RXTOALL
+#define SO_REUSE_RXTOALL                0
+#endif
+
+/*
+   ----------------------------------------
+   ---------- Statistics options ----------
+   ----------------------------------------
+*/
+/**
+ * LWIP_STATS==1: Enable statistics collection in lwip_stats.
+ */
+#ifndef LWIP_STATS
+#define LWIP_STATS                      1
+#endif
+
+#if LWIP_STATS
+
+/**
+ * LWIP_STATS_DISPLAY==1: Compile in the statistics output functions.
+ */
+#ifndef LWIP_STATS_DISPLAY
+#define LWIP_STATS_DISPLAY              0
+#endif
+
+/**
+ * LINK_STATS==1: Enable link stats.
+ */
+#ifndef LINK_STATS
+#define LINK_STATS                      1
+#endif
+
+/**
+ * ETHARP_STATS==1: Enable etharp stats.
+ */
+#ifndef ETHARP_STATS
+#define ETHARP_STATS                    (LWIP_ARP)
+#endif
+
+/**
+ * IP_STATS==1: Enable IP stats.
+ */
+#ifndef IP_STATS
+#define IP_STATS                        1
+#endif
+
+/**
+ * IPFRAG_STATS==1: Enable IP fragmentation stats. Default is
+ * on if using either frag or reass.
+ */
+#ifndef IPFRAG_STATS
+#define IPFRAG_STATS                    (IP_REASSEMBLY || IP_FRAG)
+#endif
+
+/**
+ * ICMP_STATS==1: Enable ICMP stats.
+ */
+#ifndef ICMP_STATS
+#define ICMP_STATS                      1
+#endif
+
+/**
+ * IGMP_STATS==1: Enable IGMP stats.
+ */
+#ifndef IGMP_STATS
+#define IGMP_STATS                      (LWIP_IGMP)
+#endif
+
+/**
+ * UDP_STATS==1: Enable UDP stats. Default is on if
+ * UDP enabled, otherwise off.
+ */
+#ifndef UDP_STATS
+#define UDP_STATS                       (LWIP_UDP)
+#endif
+
+/**
+ * TCP_STATS==1: Enable TCP stats. Default is on if TCP
+ * enabled, otherwise off.
+ */
+#ifndef TCP_STATS
+#define TCP_STATS                       (LWIP_TCP)
+#endif
+
+/**
+ * MEM_STATS==1: Enable mem.c stats.
+ */
+#ifndef MEM_STATS
+#define MEM_STATS                       ((MEM_LIBC_MALLOC == 0) && (MEM_USE_POOLS == 0))
+#endif
+
+/**
+ * MEMP_STATS==1: Enable memp.c pool stats.
+ */
+#ifndef MEMP_STATS
+#define MEMP_STATS                      (MEMP_MEM_MALLOC == 0)
+#endif
+
+/**
+ * SYS_STATS==1: Enable system stats (sem and mbox counts, etc).
+ */
+#ifndef SYS_STATS
+#define SYS_STATS                       (NO_SYS == 0)
+#endif
+
+#else
+
+#define LINK_STATS                      0
+#define IP_STATS                        0
+#define IPFRAG_STATS                    0
+#define ICMP_STATS                      0
+#define IGMP_STATS                      0
+#define UDP_STATS                       0
+#define TCP_STATS                       0
+#define MEM_STATS                       0
+#define MEMP_STATS                      0
+#define SYS_STATS                       0
+#define LWIP_STATS_DISPLAY              0
+
+#endif /* LWIP_STATS */
+
+/*
+   ---------------------------------
+   ---------- PPP options ----------
+   ---------------------------------
+*/
+/**
+ * PPP_SUPPORT==1: Enable PPP.
+ */
+#ifndef PPP_SUPPORT
+#define PPP_SUPPORT                     0
+#endif
+
+/**
+ * PPPOE_SUPPORT==1: Enable PPP Over Ethernet
+ */
+#ifndef PPPOE_SUPPORT
+#define PPPOE_SUPPORT                   0
+#endif
+
+/**
+ * PPPOS_SUPPORT==1: Enable PPP Over Serial
+ */
+#ifndef PPPOS_SUPPORT
+#define PPPOS_SUPPORT                   PPP_SUPPORT
+#endif
+
+#if PPP_SUPPORT
+
+/**
+ * NUM_PPP: Max PPP sessions.
+ */
+#ifndef NUM_PPP
+#define NUM_PPP                         1
+#endif
+
+/**
+ * PAP_SUPPORT==1: Support PAP.
+ */
+#ifndef PAP_SUPPORT
+#define PAP_SUPPORT                     0
+#endif
+
+/**
+ * CHAP_SUPPORT==1: Support CHAP.
+ */
+#ifndef CHAP_SUPPORT
+#define CHAP_SUPPORT                    0
+#endif
+
+/**
+ * MSCHAP_SUPPORT==1: Support MSCHAP. CURRENTLY NOT SUPPORTED! DO NOT SET!
+ */
+#ifndef MSCHAP_SUPPORT
+#define MSCHAP_SUPPORT                  0
+#endif
+
+/**
+ * CBCP_SUPPORT==1: Support CBCP. CURRENTLY NOT SUPPORTED! DO NOT SET!
+ */
+#ifndef CBCP_SUPPORT
+#define CBCP_SUPPORT                    0
+#endif
+
+/**
+ * CCP_SUPPORT==1: Support CCP. CURRENTLY NOT SUPPORTED! DO NOT SET!
+ */
+#ifndef CCP_SUPPORT
+#define CCP_SUPPORT                     0
+#endif
+
+/**
+ * VJ_SUPPORT==1: Support VJ header compression.
+ */
+#ifndef VJ_SUPPORT
+#define VJ_SUPPORT                      0
+#endif
+
+/**
+ * MD5_SUPPORT==1: Support MD5 (see also CHAP).
+ */
+#ifndef MD5_SUPPORT
+#define MD5_SUPPORT                     0
+#endif
+
+/*
+ * Timeouts
+ */
+#ifndef FSM_DEFTIMEOUT
+#define FSM_DEFTIMEOUT                  6       /* Timeout time in seconds */
+#endif
+
+#ifndef FSM_DEFMAXTERMREQS
+#define FSM_DEFMAXTERMREQS              2       /* Maximum Terminate-Request transmissions */
+#endif
+
+#ifndef FSM_DEFMAXCONFREQS
+#define FSM_DEFMAXCONFREQS              10      /* Maximum Configure-Request transmissions */
+#endif
+
+#ifndef FSM_DEFMAXNAKLOOPS
+#define FSM_DEFMAXNAKLOOPS              5       /* Maximum number of nak loops */
+#endif
+
+#ifndef UPAP_DEFTIMEOUT
+#define UPAP_DEFTIMEOUT                 6       /* Timeout (seconds) for retransmitting req */
+#endif
+
+#ifndef UPAP_DEFREQTIME
+#define UPAP_DEFREQTIME                 30      /* Time to wait for auth-req from peer */
+#endif
+
+#ifndef CHAP_DEFTIMEOUT
+#define CHAP_DEFTIMEOUT                 6       /* Timeout time in seconds */
+#endif
+
+#ifndef CHAP_DEFTRANSMITS
+#define CHAP_DEFTRANSMITS               10      /* max # times to send challenge */
+#endif
+
+/* Interval in seconds between keepalive echo requests, 0 to disable. */
+#ifndef LCP_ECHOINTERVAL
+#define LCP_ECHOINTERVAL                0
+#endif
+
+/* Number of unanswered echo requests before failure. */
+#ifndef LCP_MAXECHOFAILS
+#define LCP_MAXECHOFAILS                3
+#endif
+
+/* Max Xmit idle time (in jiffies) before resend flag char. */
+#ifndef PPP_MAXIDLEFLAG
+#define PPP_MAXIDLEFLAG                 100
+#endif
+
+/*
+ * Packet sizes
+ *
+ * Note - lcp shouldn't be allowed to negotiate stuff outside these
+ *    limits.  See lcp.h in the pppd directory.
+ * (XXX - these constants should simply be shared by lcp.c instead
+ *    of living in lcp.h)
+ */
+#define PPP_MTU                         1500     /* Default MTU (size of Info field) */
+#ifndef PPP_MAXMTU
+/* #define PPP_MAXMTU  65535 - (PPP_HDRLEN + PPP_FCSLEN) */
+#define PPP_MAXMTU                      1500 /* Largest MTU we allow */
+#endif
+#define PPP_MINMTU                      64
+#define PPP_MRU                         1500     /* default MRU = max length of info field */
+#define PPP_MAXMRU                      1500     /* Largest MRU we allow */
+#ifndef PPP_DEFMRU
+#define PPP_DEFMRU                      296             /* Try for this */
+#endif
+#define PPP_MINMRU                      128             /* No MRUs below this */
+
+#ifndef MAXNAMELEN
+#define MAXNAMELEN                      256     /* max length of hostname or name for auth */
+#endif
+#ifndef MAXSECRETLEN
+#define MAXSECRETLEN                    256     /* max length of password or secret */
+#endif
+
+#endif /* PPP_SUPPORT */
+
+/*
+   --------------------------------------
+   ---------- Checksum options ----------
+   --------------------------------------
+*/
+/**
+ * CHECKSUM_GEN_IP==1: Generate checksums in software for outgoing IP packets.
+ */
+#ifndef CHECKSUM_GEN_IP
+#define CHECKSUM_GEN_IP                 1
+#endif
+ 
+/**
+ * CHECKSUM_GEN_UDP==1: Generate checksums in software for outgoing UDP packets.
+ */
+#ifndef CHECKSUM_GEN_UDP
+#define CHECKSUM_GEN_UDP                1
+#endif
+ 
+/**
+ * CHECKSUM_GEN_TCP==1: Generate checksums in software for outgoing TCP packets.
+ */
+#ifndef CHECKSUM_GEN_TCP
+#define CHECKSUM_GEN_TCP                1
+#endif
+ 
+/**
+ * CHECKSUM_CHECK_IP==1: Check checksums in software for incoming IP packets.
+ */
+#ifndef CHECKSUM_CHECK_IP
+#define CHECKSUM_CHECK_IP               1
+#endif
+ 
+/**
+ * CHECKSUM_CHECK_UDP==1: Check checksums in software for incoming UDP packets.
+ */
+#ifndef CHECKSUM_CHECK_UDP
+#define CHECKSUM_CHECK_UDP              1
+#endif
+
+/**
+ * CHECKSUM_CHECK_TCP==1: Check checksums in software for incoming TCP packets.
+ */
+#ifndef CHECKSUM_CHECK_TCP
+#define CHECKSUM_CHECK_TCP              1
+#endif
+
+/**
+ * LWIP_CHECKSUM_ON_COPY==1: Calculate checksum when copying data from
+ * application buffers to pbufs.
+ */
+#ifndef LWIP_CHECKSUM_ON_COPY
+#define LWIP_CHECKSUM_ON_COPY           0
+#endif
+
+/*
+   ---------------------------------------
+   ---------- Debugging options ----------
+   ---------------------------------------
+*/
+/**
+ * LWIP_DBG_MIN_LEVEL: After masking, the value of the debug is
+ * compared against this value. If it is smaller, then debugging
+ * messages are written.
+ */
+#ifndef LWIP_DBG_MIN_LEVEL
+#define LWIP_DBG_MIN_LEVEL              LWIP_DBG_LEVEL_ALL
+#endif
+
+/**
+ * LWIP_DBG_TYPES_ON: A mask that can be used to globally enable/disable
+ * debug messages of certain types.
+ */
+#ifndef LWIP_DBG_TYPES_ON
+#define LWIP_DBG_TYPES_ON               LWIP_DBG_ON
+#endif
+
+/**
+ * ETHARP_DEBUG: Enable debugging in etharp.c.
+ */
+#ifndef ETHARP_DEBUG
+#define ETHARP_DEBUG                    LWIP_DBG_OFF
+#endif
+
+/**
+ * NETIF_DEBUG: Enable debugging in netif.c.
+ */
+#ifndef NETIF_DEBUG
+#define NETIF_DEBUG                     LWIP_DBG_OFF
+#endif
+
+/**
+ * PBUF_DEBUG: Enable debugging in pbuf.c.
+ */
+#ifndef PBUF_DEBUG
+#define PBUF_DEBUG                      LWIP_DBG_OFF
+#endif
+
+/**
+ * API_LIB_DEBUG: Enable debugging in api_lib.c.
+ */
+#ifndef API_LIB_DEBUG
+#define API_LIB_DEBUG                   LWIP_DBG_OFF
+#endif
+
+/**
+ * API_MSG_DEBUG: Enable debugging in api_msg.c.
+ */
+#ifndef API_MSG_DEBUG
+#define API_MSG_DEBUG                   LWIP_DBG_OFF
+#endif
+
+/**
+ * SOCKETS_DEBUG: Enable debugging in sockets.c.
+ */
+#ifndef SOCKETS_DEBUG
+#define SOCKETS_DEBUG                   LWIP_DBG_OFF
+#endif
+
+/**
+ * ICMP_DEBUG: Enable debugging in icmp.c.
+ */
+#ifndef ICMP_DEBUG
+#define ICMP_DEBUG                      LWIP_DBG_OFF
+#endif
+
+/**
+ * IGMP_DEBUG: Enable debugging in igmp.c.
+ */
+#ifndef IGMP_DEBUG
+#define IGMP_DEBUG                      LWIP_DBG_OFF
+#endif
+
+/**
+ * INET_DEBUG: Enable debugging in inet.c.
+ */
+#ifndef INET_DEBUG
+#define INET_DEBUG                      LWIP_DBG_OFF
+#endif
+
+/**
+ * IP_DEBUG: Enable debugging for IP.
+ */
+#ifndef IP_DEBUG
+#define IP_DEBUG                        LWIP_DBG_OFF
+#endif
+
+/**
+ * IP_REASS_DEBUG: Enable debugging in ip_frag.c for both frag & reass.
+ */
+#ifndef IP_REASS_DEBUG
+#define IP_REASS_DEBUG                  LWIP_DBG_OFF
+#endif
+
+/**
+ * RAW_DEBUG: Enable debugging in raw.c.
+ */
+#ifndef RAW_DEBUG
+#define RAW_DEBUG                       LWIP_DBG_OFF
+#endif
+
+/**
+ * MEM_DEBUG: Enable debugging in mem.c.
+ */
+#ifndef MEM_DEBUG
+#define MEM_DEBUG                       LWIP_DBG_OFF
+#endif
+
+/**
+ * MEMP_DEBUG: Enable debugging in memp.c.
+ */
+#ifndef MEMP_DEBUG
+#define MEMP_DEBUG                      LWIP_DBG_OFF
+#endif
+
+/**
+ * SYS_DEBUG: Enable debugging in sys.c.
+ */
+#ifndef SYS_DEBUG
+#define SYS_DEBUG                       LWIP_DBG_OFF
+#endif
+
+/**
+ * TIMERS_DEBUG: Enable debugging in timers.c.
+ */
+#ifndef TIMERS_DEBUG
+#define TIMERS_DEBUG                    LWIP_DBG_OFF
+#endif
+
+/**
+ * TCP_DEBUG: Enable debugging for TCP.
+ */
+#ifndef TCP_DEBUG
+#define TCP_DEBUG                       LWIP_DBG_OFF
+#endif
+
+/**
+ * TCP_INPUT_DEBUG: Enable debugging in tcp_in.c for incoming debug.
+ */
+#ifndef TCP_INPUT_DEBUG
+#define TCP_INPUT_DEBUG                 LWIP_DBG_OFF
+#endif
+
+/**
+ * TCP_FR_DEBUG: Enable debugging in tcp_in.c for fast retransmit.
+ */
+#ifndef TCP_FR_DEBUG
+#define TCP_FR_DEBUG                    LWIP_DBG_OFF
+#endif
+
+/**
+ * TCP_RTO_DEBUG: Enable debugging in TCP for retransmit
+ * timeout.
+ */
+#ifndef TCP_RTO_DEBUG
+#define TCP_RTO_DEBUG                   LWIP_DBG_OFF
+#endif
+
+/**
+ * TCP_CWND_DEBUG: Enable debugging for TCP congestion window.
+ */
+#ifndef TCP_CWND_DEBUG
+#define TCP_CWND_DEBUG                  LWIP_DBG_OFF
+#endif
+
+/**
+ * TCP_WND_DEBUG: Enable debugging in tcp_in.c for window updating.
+ */
+#ifndef TCP_WND_DEBUG
+#define TCP_WND_DEBUG                   LWIP_DBG_OFF
+#endif
+
+/**
+ * TCP_OUTPUT_DEBUG: Enable debugging in tcp_out.c output functions.
+ */
+#ifndef TCP_OUTPUT_DEBUG
+#define TCP_OUTPUT_DEBUG                LWIP_DBG_OFF
+#endif
+
+/**
+ * TCP_RST_DEBUG: Enable debugging for TCP with the RST message.
+ */
+#ifndef TCP_RST_DEBUG
+#define TCP_RST_DEBUG                   LWIP_DBG_OFF
+#endif
+
+/**
+ * TCP_QLEN_DEBUG: Enable debugging for TCP queue lengths.
+ */
+#ifndef TCP_QLEN_DEBUG
+#define TCP_QLEN_DEBUG                  LWIP_DBG_OFF
+#endif
+
+/**
+ * UDP_DEBUG: Enable debugging in UDP.
+ */
+#ifndef UDP_DEBUG
+#define UDP_DEBUG                       LWIP_DBG_OFF
+#endif
+
+/**
+ * TCPIP_DEBUG: Enable debugging in tcpip.c.
+ */
+#ifndef TCPIP_DEBUG
+#define TCPIP_DEBUG                     LWIP_DBG_OFF
+#endif
+
+/**
+ * PPP_DEBUG: Enable debugging for PPP.
+ */
+#ifndef PPP_DEBUG
+#define PPP_DEBUG                       LWIP_DBG_OFF
+#endif
+
+/**
+ * SLIP_DEBUG: Enable debugging in slipif.c.
+ */
+#ifndef SLIP_DEBUG
+#define SLIP_DEBUG                      LWIP_DBG_OFF
+#endif
+
+/**
+ * DHCP_DEBUG: Enable debugging in dhcp.c.
+ */
+#ifndef DHCP_DEBUG
+#define DHCP_DEBUG                      LWIP_DBG_OFF
+#endif
+
+/**
+ * AUTOIP_DEBUG: Enable debugging in autoip.c.
+ */
+#ifndef AUTOIP_DEBUG
+#define AUTOIP_DEBUG                    LWIP_DBG_OFF
+#endif
+
+/**
+ * SNMP_MSG_DEBUG: Enable debugging for SNMP messages.
+ */
+#ifndef SNMP_MSG_DEBUG
+#define SNMP_MSG_DEBUG                  LWIP_DBG_OFF
+#endif
+
+/**
+ * SNMP_MIB_DEBUG: Enable debugging for SNMP MIBs.
+ */
+#ifndef SNMP_MIB_DEBUG
+#define SNMP_MIB_DEBUG                  LWIP_DBG_OFF
+#endif
+
+/**
+ * DNS_DEBUG: Enable debugging for DNS.
+ */
+#ifndef DNS_DEBUG
+#define DNS_DEBUG                       LWIP_DBG_OFF
+#endif
+
+#endif /* __LWIP_OPT_H__ */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/include/lwip/pbuf.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,154 @@
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+
+#ifndef __LWIP_PBUF_H__
+#define __LWIP_PBUF_H__
+
+#include "lwip/opt.h"
+#include "lwip/err.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* Currently, the pbuf_custom code is only needed for one specific configuration
+ * of IP_FRAG */
+#define LWIP_SUPPORT_CUSTOM_PBUF (IP_FRAG && !IP_FRAG_USES_STATIC_BUF && !LWIP_NETIF_TX_SINGLE_PBUF)
+
+#define PBUF_TRANSPORT_HLEN 20
+#define PBUF_IP_HLEN        20
+
+typedef enum {
+  PBUF_TRANSPORT,
+  PBUF_IP,
+  PBUF_LINK,
+  PBUF_RAW
+} pbuf_layer;
+
+typedef enum {
+  PBUF_RAM, /* pbuf data is stored in RAM */
+  PBUF_ROM, /* pbuf data is stored in ROM */
+  PBUF_REF, /* pbuf comes from the pbuf pool */
+  PBUF_POOL /* pbuf payload refers to RAM */
+} pbuf_type;
+
+
+/* indicates this packet's data should be immediately passed to the application */
+#define PBUF_FLAG_PUSH      0x01U
+/* indicates this is a custom pbuf: pbuf_free and pbuf_header handle such a
+    a pbuf differently */
+#define PBUF_FLAG_IS_CUSTOM 0x02U
+/* indicates this pbuf is UDP multicast to be looped back */
+#define PBUF_FLAG_MCASTLOOP 0x04U
+
+struct pbuf {
+  /* next pbuf in singly linked pbuf chain */
+  struct pbuf *next;
+
+  /* pointer to the actual data in the buffer */
+  void *payload;
+
+  /**
+   * total length of this buffer and all next buffers in chain
+   * belonging to the same packet.
+   *
+   * For non-queue packet chains this is the invariant:
+   * p->tot_len == p->len + (p->next? p->next->tot_len: 0)
+   */
+  u16_t tot_len;
+
+  /* length of this buffer */
+  u16_t len;
+
+  /* pbuf_type as u8_t instead of enum to save space */
+  u8_t /*pbuf_type*/ type;
+
+  /* misc flags */
+  u8_t flags;
+
+  /**
+   * the reference count always equals the number of pointers
+   * that refer to this pbuf. This can be pointers from an application,
+   * the stack itself, or pbuf->next pointers from a chain.
+   */
+  u16_t ref;
+};
+
+#if LWIP_SUPPORT_CUSTOM_PBUF
+/* Prototype for a function to free a custom pbuf */
+typedef void (*pbuf_free_custom_fn)(struct pbuf *p);
+
+/* A custom pbuf: like a pbuf, but following a function pointer to free it. */
+struct pbuf_custom {
+  /* The actual pbuf */
+  struct pbuf pbuf;
+  /* This function is called when pbuf_free deallocates this pbuf(_custom) */
+  pbuf_free_custom_fn custom_free_function;
+};
+#endif /* LWIP_SUPPORT_CUSTOM_PBUF */
+
+/* Initializes the pbuf module. This call is empty for now, but may not be in future. */
+#define pbuf_init()
+
+struct pbuf *pbuf_alloc(pbuf_layer l, u16_t length, pbuf_type type);
+#if LWIP_SUPPORT_CUSTOM_PBUF
+struct pbuf *pbuf_alloced_custom(pbuf_layer l, u16_t length, pbuf_type type,
+                                 struct pbuf_custom *p, void *payload_mem,
+                                 u16_t payload_mem_len);
+#endif /* LWIP_SUPPORT_CUSTOM_PBUF */
+void pbuf_realloc(struct pbuf *p, u16_t size); 
+u8_t pbuf_header(struct pbuf *p, s16_t header_size);
+void pbuf_ref(struct pbuf *p);
+u8_t pbuf_free(struct pbuf *p);
+u8_t pbuf_clen(struct pbuf *p);  
+void pbuf_cat(struct pbuf *head, struct pbuf *tail);
+void pbuf_chain(struct pbuf *head, struct pbuf *tail);
+struct pbuf *pbuf_dechain(struct pbuf *p);
+err_t pbuf_copy(struct pbuf *p_to, struct pbuf *p_from);
+u16_t pbuf_copy_partial(struct pbuf *p, void *dataptr, u16_t len, u16_t offset);
+err_t pbuf_take(struct pbuf *buf, const void *dataptr, u16_t len);
+struct pbuf *pbuf_coalesce(struct pbuf *p, pbuf_layer layer);
+#if LWIP_CHECKSUM_ON_COPY
+err_t pbuf_fill_chksum(struct pbuf *p, u16_t start_offset, const void *dataptr,
+                       u16_t len, u16_t *chksum);
+#endif /* LWIP_CHECKSUM_ON_COPY */
+
+u8_t pbuf_get_at(struct pbuf* p, u16_t offset);
+u16_t pbuf_memcmp(struct pbuf* p, u16_t offset, const void* s2, u16_t n);
+u16_t pbuf_memfind(struct pbuf* p, const void* mem, u16_t mem_len, u16_t start_offset);
+u16_t pbuf_strstr(struct pbuf* p, const char* substr);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __LWIP_PBUF_H__ */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/include/lwip/raw.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,98 @@
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ *
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+#ifndef __LWIP_RAW_H__
+#define __LWIP_RAW_H__
+
+#include "lwip/opt.h"
+
+#if LWIP_RAW /* don't build if not configured for use in lwipopts.h */
+
+#include "lwip/pbuf.h"
+#include "lwip/def.h"
+#include "lwip/ip.h"
+#include "lwip/ip_addr.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+struct raw_pcb;
+
+/** Function prototype for raw pcb receive callback functions.
+ * @param arg user supplied argument (raw_pcb.recv_arg)
+ * @param pcb the raw_pcb which received data
+ * @param p the packet buffer that was received
+ * @param addr the remote IP address from which the packet was received
+ * @return 1 if the packet was 'eaten' (aka. deleted),
+ *         0 if the packet lives on
+ * If returning 1, the callback is responsible for freeing the pbuf
+ * if it's not used any more.
+ */
+typedef u8_t (*raw_recv_fn)(void *arg, struct raw_pcb *pcb, struct pbuf *p,
+    ip_addr_t *addr);
+
+struct raw_pcb {
+  /* Common members of all PCB types */
+  IP_PCB;
+
+  struct raw_pcb *next;
+
+  u8_t protocol;
+
+  /** receive callback function */
+  raw_recv_fn recv;
+  /* user-supplied argument for the recv callback */
+  void *recv_arg;
+};
+
+/* The following functions is the application layer interface to the
+   RAW code. */
+struct raw_pcb * raw_new        (u8_t proto);
+void             raw_remove     (struct raw_pcb *pcb);
+err_t            raw_bind       (struct raw_pcb *pcb, ip_addr_t *ipaddr);
+err_t            raw_connect    (struct raw_pcb *pcb, ip_addr_t *ipaddr);
+
+void             raw_recv       (struct raw_pcb *pcb, raw_recv_fn recv, void *recv_arg);
+err_t            raw_sendto     (struct raw_pcb *pcb, struct pbuf *p, ip_addr_t *ipaddr);
+err_t            raw_send       (struct raw_pcb *pcb, struct pbuf *p);
+
+/* The following functions are the lower layer interface to RAW. */
+u8_t             raw_input      (struct pbuf *p, struct netif *inp);
+#define raw_init() /* Compatibility define, not init needed. */
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* LWIP_RAW */
+
+#endif /* __LWIP_RAW_H__ */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/include/lwip/sio.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,141 @@
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ */
+
+/*
+ * This is the interface to the platform specific serial IO module
+ * It needs to be implemented by those platforms which need SLIP or PPP
+ */
+
+#ifndef __SIO_H__
+#define __SIO_H__
+
+#include "lwip/arch.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* If you want to define sio_fd_t elsewhere or differently,
+   define this in your cc.h file. */
+#ifndef __sio_fd_t_defined
+typedef void * sio_fd_t;
+#endif
+
+/* The following functions can be defined to something else in your cc.h file
+   or be implemented in your custom sio.c file. */
+
+#ifndef sio_open
+/**
+ * Opens a serial device for communication.
+ * 
+ * @param devnum device number
+ * @return handle to serial device if successful, NULL otherwise
+ */
+sio_fd_t sio_open(u8_t devnum);
+#endif
+
+#ifndef sio_send
+/**
+ * Sends a single character to the serial device.
+ * 
+ * @param c character to send
+ * @param fd serial device handle
+ * 
+ * @note This function will block until the character can be sent.
+ */
+void sio_send(u8_t c, sio_fd_t fd);
+#endif
+
+#ifndef sio_recv
+/**
+ * Receives a single character from the serial device.
+ * 
+ * @param fd serial device handle
+ * 
+ * @note This function will block until a character is received.
+ */
+u8_t sio_recv(sio_fd_t fd);
+#endif
+
+#ifndef sio_read
+/**
+ * Reads from the serial device.
+ * 
+ * @param fd serial device handle
+ * @param data pointer to data buffer for receiving
+ * @param len maximum length (in bytes) of data to receive
+ * @return number of bytes actually received - may be 0 if aborted by sio_read_abort
+ * 
+ * @note This function will block until data can be received. The blocking
+ * can be cancelled by calling sio_read_abort().
+ */
+u32_t sio_read(sio_fd_t fd, u8_t *data, u32_t len);
+#endif
+
+#ifndef sio_tryread
+/**
+ * Tries to read from the serial device. Same as sio_read but returns
+ * immediately if no data is available and never blocks.
+ * 
+ * @param fd serial device handle
+ * @param data pointer to data buffer for receiving
+ * @param len maximum length (in bytes) of data to receive
+ * @return number of bytes actually received
+ */
+u32_t sio_tryread(sio_fd_t fd, u8_t *data, u32_t len);
+#endif
+
+#ifndef sio_write
+/**
+ * Writes to the serial device.
+ * 
+ * @param fd serial device handle
+ * @param data pointer to data to send
+ * @param len length (in bytes) of data to send
+ * @return number of bytes actually sent
+ * 
+ * @note This function will block until all data can be sent.
+ */
+u32_t sio_write(sio_fd_t fd, u8_t *data, u32_t len);
+#endif
+
+#ifndef sio_read_abort
+/**
+ * Aborts a blocking sio_read() call.
+ * 
+ * @param fd serial device handle
+ */
+void sio_read_abort(sio_fd_t fd);
+#endif
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __SIO_H__ */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/include/lwip/snmp.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,367 @@
+/*
+ * Copyright (c) 2001, 2002 Leon Woestenberg <leon.woestenberg@axon.tv>
+ * Copyright (c) 2001, 2002 Axon Digital Design B.V., The Netherlands.
+ * All rights reserved.
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Leon Woestenberg <leon.woestenberg@axon.tv>
+ *
+ */
+#ifndef __LWIP_SNMP_H__
+#define __LWIP_SNMP_H__
+
+#include "lwip/opt.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include "lwip/ip_addr.h"
+
+struct udp_pcb;
+struct netif;
+
+/**
+ * @see RFC1213, "MIB-II, 6. Definitions"
+ */
+enum snmp_ifType {
+  snmp_ifType_other=1,                /* none of the following */
+  snmp_ifType_regular1822,
+  snmp_ifType_hdh1822,
+  snmp_ifType_ddn_x25,
+  snmp_ifType_rfc877_x25,
+  snmp_ifType_ethernet_csmacd,
+  snmp_ifType_iso88023_csmacd,
+  snmp_ifType_iso88024_tokenBus,
+  snmp_ifType_iso88025_tokenRing,
+  snmp_ifType_iso88026_man,
+  snmp_ifType_starLan,
+  snmp_ifType_proteon_10Mbit,
+  snmp_ifType_proteon_80Mbit,
+  snmp_ifType_hyperchannel,
+  snmp_ifType_fddi,
+  snmp_ifType_lapb,
+  snmp_ifType_sdlc,
+  snmp_ifType_ds1,                    /* T-1 */
+  snmp_ifType_e1,                     /* european equiv. of T-1 */
+  snmp_ifType_basicISDN,
+  snmp_ifType_primaryISDN,            /* proprietary serial */
+  snmp_ifType_propPointToPointSerial,
+  snmp_ifType_ppp,
+  snmp_ifType_softwareLoopback,
+  snmp_ifType_eon,                    /* CLNP over IP [11] */
+  snmp_ifType_ethernet_3Mbit,
+  snmp_ifType_nsip,                   /* XNS over IP */
+  snmp_ifType_slip,                   /* generic SLIP */
+  snmp_ifType_ultra,                  /* ULTRA technologies */
+  snmp_ifType_ds3,                    /* T-3 */
+  snmp_ifType_sip,                    /* SMDS */
+  snmp_ifType_frame_relay
+};
+
+#if LWIP_SNMP /* don't build if not configured for use in lwipopts.h */
+
+/** SNMP "sysuptime" Interval */
+#define SNMP_SYSUPTIME_INTERVAL 10
+
+/** fixed maximum length for object identifier type */
+#define LWIP_SNMP_OBJ_ID_LEN 32
+
+/** internal object identifier representation */
+struct snmp_obj_id
+{
+  u8_t len;
+  s32_t id[LWIP_SNMP_OBJ_ID_LEN];
+};
+
+/* system */
+void snmp_set_sysdesr(u8_t* str, u8_t* len);
+void snmp_set_sysobjid(struct snmp_obj_id *oid);
+void snmp_get_sysobjid_ptr(struct snmp_obj_id **oid);
+void snmp_inc_sysuptime(void);
+void snmp_add_sysuptime(u32_t value);
+void snmp_get_sysuptime(u32_t *value);
+void snmp_set_syscontact(u8_t *ocstr, u8_t *ocstrlen);
+void snmp_set_sysname(u8_t *ocstr, u8_t *ocstrlen);
+void snmp_set_syslocation(u8_t *ocstr, u8_t *ocstrlen);
+
+/* network interface */
+void snmp_add_ifinoctets(struct netif *ni, u32_t value); 
+void snmp_inc_ifinucastpkts(struct netif *ni);
+void snmp_inc_ifinnucastpkts(struct netif *ni);
+void snmp_inc_ifindiscards(struct netif *ni);
+void snmp_add_ifoutoctets(struct netif *ni, u32_t value);
+void snmp_inc_ifoutucastpkts(struct netif *ni);
+void snmp_inc_ifoutnucastpkts(struct netif *ni);
+void snmp_inc_ifoutdiscards(struct netif *ni);
+void snmp_inc_iflist(void);
+void snmp_dec_iflist(void);
+
+/* ARP (for atTable and ipNetToMediaTable) */
+void snmp_insert_arpidx_tree(struct netif *ni, ip_addr_t *ip);
+void snmp_delete_arpidx_tree(struct netif *ni, ip_addr_t *ip);
+
+/* IP */
+void snmp_inc_ipinreceives(void);
+void snmp_inc_ipinhdrerrors(void);
+void snmp_inc_ipinaddrerrors(void);
+void snmp_inc_ipforwdatagrams(void);
+void snmp_inc_ipinunknownprotos(void);
+void snmp_inc_ipindiscards(void);
+void snmp_inc_ipindelivers(void);
+void snmp_inc_ipoutrequests(void);
+void snmp_inc_ipoutdiscards(void);
+void snmp_inc_ipoutnoroutes(void);
+void snmp_inc_ipreasmreqds(void);
+void snmp_inc_ipreasmoks(void);
+void snmp_inc_ipreasmfails(void);
+void snmp_inc_ipfragoks(void);
+void snmp_inc_ipfragfails(void);
+void snmp_inc_ipfragcreates(void);
+void snmp_inc_iproutingdiscards(void);
+void snmp_insert_ipaddridx_tree(struct netif *ni);
+void snmp_delete_ipaddridx_tree(struct netif *ni);
+void snmp_insert_iprteidx_tree(u8_t dflt, struct netif *ni);
+void snmp_delete_iprteidx_tree(u8_t dflt, struct netif *ni);
+
+/* ICMP */
+void snmp_inc_icmpinmsgs(void);
+void snmp_inc_icmpinerrors(void);
+void snmp_inc_icmpindestunreachs(void);
+void snmp_inc_icmpintimeexcds(void);
+void snmp_inc_icmpinparmprobs(void);
+void snmp_inc_icmpinsrcquenchs(void);
+void snmp_inc_icmpinredirects(void);
+void snmp_inc_icmpinechos(void);
+void snmp_inc_icmpinechoreps(void);
+void snmp_inc_icmpintimestamps(void);
+void snmp_inc_icmpintimestampreps(void);
+void snmp_inc_icmpinaddrmasks(void);
+void snmp_inc_icmpinaddrmaskreps(void);
+void snmp_inc_icmpoutmsgs(void);
+void snmp_inc_icmpouterrors(void);
+void snmp_inc_icmpoutdestunreachs(void);
+void snmp_inc_icmpouttimeexcds(void);
+void snmp_inc_icmpoutparmprobs(void);
+void snmp_inc_icmpoutsrcquenchs(void);
+void snmp_inc_icmpoutredirects(void); 
+void snmp_inc_icmpoutechos(void);
+void snmp_inc_icmpoutechoreps(void);
+void snmp_inc_icmpouttimestamps(void);
+void snmp_inc_icmpouttimestampreps(void);
+void snmp_inc_icmpoutaddrmasks(void);
+void snmp_inc_icmpoutaddrmaskreps(void);
+
+/* TCP */
+void snmp_inc_tcpactiveopens(void);
+void snmp_inc_tcppassiveopens(void);
+void snmp_inc_tcpattemptfails(void);
+void snmp_inc_tcpestabresets(void);
+void snmp_inc_tcpinsegs(void);
+void snmp_inc_tcpoutsegs(void);
+void snmp_inc_tcpretranssegs(void);
+void snmp_inc_tcpinerrs(void);
+void snmp_inc_tcpoutrsts(void);
+
+/* UDP */
+void snmp_inc_udpindatagrams(void);
+void snmp_inc_udpnoports(void);
+void snmp_inc_udpinerrors(void);
+void snmp_inc_udpoutdatagrams(void);
+void snmp_insert_udpidx_tree(struct udp_pcb *pcb);
+void snmp_delete_udpidx_tree(struct udp_pcb *pcb);
+
+/* SNMP */
+void snmp_inc_snmpinpkts(void);
+void snmp_inc_snmpoutpkts(void);
+void snmp_inc_snmpinbadversions(void);
+void snmp_inc_snmpinbadcommunitynames(void);
+void snmp_inc_snmpinbadcommunityuses(void);
+void snmp_inc_snmpinasnparseerrs(void);
+void snmp_inc_snmpintoobigs(void);
+void snmp_inc_snmpinnosuchnames(void);
+void snmp_inc_snmpinbadvalues(void);
+void snmp_inc_snmpinreadonlys(void);
+void snmp_inc_snmpingenerrs(void);
+void snmp_add_snmpintotalreqvars(u8_t value);
+void snmp_add_snmpintotalsetvars(u8_t value);
+void snmp_inc_snmpingetrequests(void);
+void snmp_inc_snmpingetnexts(void);
+void snmp_inc_snmpinsetrequests(void);
+void snmp_inc_snmpingetresponses(void);
+void snmp_inc_snmpintraps(void);
+void snmp_inc_snmpouttoobigs(void);
+void snmp_inc_snmpoutnosuchnames(void);
+void snmp_inc_snmpoutbadvalues(void);
+void snmp_inc_snmpoutgenerrs(void);
+void snmp_inc_snmpoutgetrequests(void);
+void snmp_inc_snmpoutgetnexts(void);
+void snmp_inc_snmpoutsetrequests(void);
+void snmp_inc_snmpoutgetresponses(void);
+void snmp_inc_snmpouttraps(void);
+void snmp_get_snmpgrpid_ptr(struct snmp_obj_id **oid);
+void snmp_set_snmpenableauthentraps(u8_t *value);
+void snmp_get_snmpenableauthentraps(u8_t *value);
+
+/* LWIP_SNMP support not available */
+/* define everything to be empty */
+#else
+
+/* system */
+#define snmp_set_sysdesr(str, len)
+#define snmp_set_sysobjid(oid);
+#define snmp_get_sysobjid_ptr(oid)
+#define snmp_inc_sysuptime()
+#define snmp_add_sysuptime(value)
+#define snmp_get_sysuptime(value)
+#define snmp_set_syscontact(ocstr, ocstrlen);
+#define snmp_set_sysname(ocstr, ocstrlen);
+#define snmp_set_syslocation(ocstr, ocstrlen);
+
+/* network interface */
+#define snmp_add_ifinoctets(ni,value) 
+#define snmp_inc_ifinucastpkts(ni)
+#define snmp_inc_ifinnucastpkts(ni)
+#define snmp_inc_ifindiscards(ni)
+#define snmp_add_ifoutoctets(ni,value)
+#define snmp_inc_ifoutucastpkts(ni)
+#define snmp_inc_ifoutnucastpkts(ni)
+#define snmp_inc_ifoutdiscards(ni)
+#define snmp_inc_iflist()
+#define snmp_dec_iflist()
+
+/* ARP */
+#define snmp_insert_arpidx_tree(ni,ip)
+#define snmp_delete_arpidx_tree(ni,ip)
+
+/* IP */
+#define snmp_inc_ipinreceives()
+#define snmp_inc_ipinhdrerrors()
+#define snmp_inc_ipinaddrerrors()
+#define snmp_inc_ipforwdatagrams()
+#define snmp_inc_ipinunknownprotos()
+#define snmp_inc_ipindiscards()
+#define snmp_inc_ipindelivers()
+#define snmp_inc_ipoutrequests()
+#define snmp_inc_ipoutdiscards()
+#define snmp_inc_ipoutnoroutes()
+#define snmp_inc_ipreasmreqds()
+#define snmp_inc_ipreasmoks()
+#define snmp_inc_ipreasmfails()
+#define snmp_inc_ipfragoks()
+#define snmp_inc_ipfragfails()
+#define snmp_inc_ipfragcreates()
+#define snmp_inc_iproutingdiscards()
+#define snmp_insert_ipaddridx_tree(ni)
+#define snmp_delete_ipaddridx_tree(ni)
+#define snmp_insert_iprteidx_tree(dflt, ni)
+#define snmp_delete_iprteidx_tree(dflt, ni)
+
+/* ICMP */
+#define snmp_inc_icmpinmsgs()
+#define snmp_inc_icmpinerrors() 
+#define snmp_inc_icmpindestunreachs() 
+#define snmp_inc_icmpintimeexcds()
+#define snmp_inc_icmpinparmprobs() 
+#define snmp_inc_icmpinsrcquenchs() 
+#define snmp_inc_icmpinredirects() 
+#define snmp_inc_icmpinechos() 
+#define snmp_inc_icmpinechoreps()
+#define snmp_inc_icmpintimestamps() 
+#define snmp_inc_icmpintimestampreps()
+#define snmp_inc_icmpinaddrmasks()
+#define snmp_inc_icmpinaddrmaskreps()
+#define snmp_inc_icmpoutmsgs()
+#define snmp_inc_icmpouterrors()
+#define snmp_inc_icmpoutdestunreachs() 
+#define snmp_inc_icmpouttimeexcds() 
+#define snmp_inc_icmpoutparmprobs()
+#define snmp_inc_icmpoutsrcquenchs()
+#define snmp_inc_icmpoutredirects() 
+#define snmp_inc_icmpoutechos() 
+#define snmp_inc_icmpoutechoreps()
+#define snmp_inc_icmpouttimestamps()
+#define snmp_inc_icmpouttimestampreps()
+#define snmp_inc_icmpoutaddrmasks()
+#define snmp_inc_icmpoutaddrmaskreps()
+/* TCP */
+#define snmp_inc_tcpactiveopens()
+#define snmp_inc_tcppassiveopens()
+#define snmp_inc_tcpattemptfails()
+#define snmp_inc_tcpestabresets()
+#define snmp_inc_tcpinsegs()
+#define snmp_inc_tcpoutsegs()
+#define snmp_inc_tcpretranssegs()
+#define snmp_inc_tcpinerrs()
+#define snmp_inc_tcpoutrsts()
+
+/* UDP */
+#define snmp_inc_udpindatagrams()
+#define snmp_inc_udpnoports()
+#define snmp_inc_udpinerrors()
+#define snmp_inc_udpoutdatagrams()
+#define snmp_insert_udpidx_tree(pcb)
+#define snmp_delete_udpidx_tree(pcb)
+
+/* SNMP */
+#define snmp_inc_snmpinpkts()
+#define snmp_inc_snmpoutpkts()
+#define snmp_inc_snmpinbadversions()
+#define snmp_inc_snmpinbadcommunitynames()
+#define snmp_inc_snmpinbadcommunityuses()
+#define snmp_inc_snmpinasnparseerrs()
+#define snmp_inc_snmpintoobigs()
+#define snmp_inc_snmpinnosuchnames()
+#define snmp_inc_snmpinbadvalues()
+#define snmp_inc_snmpinreadonlys()
+#define snmp_inc_snmpingenerrs()
+#define snmp_add_snmpintotalreqvars(value)
+#define snmp_add_snmpintotalsetvars(value)
+#define snmp_inc_snmpingetrequests()
+#define snmp_inc_snmpingetnexts()
+#define snmp_inc_snmpinsetrequests()
+#define snmp_inc_snmpingetresponses()
+#define snmp_inc_snmpintraps()
+#define snmp_inc_snmpouttoobigs()
+#define snmp_inc_snmpoutnosuchnames()
+#define snmp_inc_snmpoutbadvalues()
+#define snmp_inc_snmpoutgenerrs()
+#define snmp_inc_snmpoutgetrequests()
+#define snmp_inc_snmpoutgetnexts()
+#define snmp_inc_snmpoutsetrequests()
+#define snmp_inc_snmpoutgetresponses()
+#define snmp_inc_snmpouttraps()
+#define snmp_get_snmpgrpid_ptr(oid)
+#define snmp_set_snmpenableauthentraps(value)
+#define snmp_get_snmpenableauthentraps(value)
+
+#endif /* LWIP_SNMP */
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __LWIP_SNMP_H__ */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/include/lwip/snmp_asn1.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,101 @@
+/**
+ * @file
+ * Abstract Syntax Notation One (ISO 8824, 8825) codec.
+ */
+ 
+/*
+ * Copyright (c) 2006 Axon Digital Design B.V., The Netherlands.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * Author: Christiaan Simons <christiaan.simons@axon.tv>
+ */
+
+#ifndef __LWIP_SNMP_ASN1_H__
+#define __LWIP_SNMP_ASN1_H__
+
+#include "lwip/opt.h"
+#include "lwip/err.h"
+#include "lwip/pbuf.h"
+#include "lwip/snmp.h"
+
+#if LWIP_SNMP
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#define SNMP_ASN1_UNIV   (0)    /* (!0x80 | !0x40) */
+#define SNMP_ASN1_APPLIC (0x40) /* (!0x80 |  0x40) */
+#define SNMP_ASN1_CONTXT (0x80) /* ( 0x80 | !0x40) */
+
+#define SNMP_ASN1_CONSTR (0x20) /* ( 0x20) */
+#define SNMP_ASN1_PRIMIT (0)    /* (!0x20) */
+
+/* universal tags */
+#define SNMP_ASN1_INTEG  2
+#define SNMP_ASN1_OC_STR 4
+#define SNMP_ASN1_NUL    5
+#define SNMP_ASN1_OBJ_ID 6
+#define SNMP_ASN1_SEQ    16
+
+/* application specific (SNMP) tags */
+#define SNMP_ASN1_IPADDR 0    /* octet string size(4) */
+#define SNMP_ASN1_COUNTER 1   /* u32_t */
+#define SNMP_ASN1_GAUGE 2     /* u32_t */
+#define SNMP_ASN1_TIMETICKS 3 /* u32_t */
+#define SNMP_ASN1_OPAQUE 4    /* octet string */
+
+/* context specific (SNMP) tags */
+#define SNMP_ASN1_PDU_GET_REQ 0
+#define SNMP_ASN1_PDU_GET_NEXT_REQ 1
+#define SNMP_ASN1_PDU_GET_RESP 2
+#define SNMP_ASN1_PDU_SET_REQ 3
+#define SNMP_ASN1_PDU_TRAP 4
+
+err_t snmp_asn1_dec_type(struct pbuf *p, u16_t ofs, u8_t *type);
+err_t snmp_asn1_dec_length(struct pbuf *p, u16_t ofs, u8_t *octets_used, u16_t *length);
+err_t snmp_asn1_dec_u32t(struct pbuf *p, u16_t ofs, u16_t len, u32_t *value);
+err_t snmp_asn1_dec_s32t(struct pbuf *p, u16_t ofs, u16_t len, s32_t *value);
+err_t snmp_asn1_dec_oid(struct pbuf *p, u16_t ofs, u16_t len, struct snmp_obj_id *oid);
+err_t snmp_asn1_dec_raw(struct pbuf *p, u16_t ofs, u16_t len, u16_t raw_len, u8_t *raw);
+
+void snmp_asn1_enc_length_cnt(u16_t length, u8_t *octets_needed);
+void snmp_asn1_enc_u32t_cnt(u32_t value, u16_t *octets_needed);
+void snmp_asn1_enc_s32t_cnt(s32_t value, u16_t *octets_needed);
+void snmp_asn1_enc_oid_cnt(u8_t ident_len, s32_t *ident, u16_t *octets_needed);
+err_t snmp_asn1_enc_type(struct pbuf *p, u16_t ofs, u8_t type);
+err_t snmp_asn1_enc_length(struct pbuf *p, u16_t ofs, u16_t length);
+err_t snmp_asn1_enc_u32t(struct pbuf *p, u16_t ofs, u16_t octets_needed, u32_t value);
+err_t snmp_asn1_enc_s32t(struct pbuf *p, u16_t ofs, u16_t octets_needed, s32_t value);
+err_t snmp_asn1_enc_oid(struct pbuf *p, u16_t ofs, u8_t ident_len, s32_t *ident);
+err_t snmp_asn1_enc_raw(struct pbuf *p, u16_t ofs, u16_t raw_len, u8_t *raw);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* LWIP_SNMP */
+
+#endif /* __LWIP_SNMP_ASN1_H__ */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/include/lwip/snmp_msg.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,315 @@
+/**
+ * @file
+ * SNMP Agent message handling structures.
+ */
+
+/*
+ * Copyright (c) 2006 Axon Digital Design B.V., The Netherlands.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * Author: Christiaan Simons <christiaan.simons@axon.tv>
+ */
+
+#ifndef __LWIP_SNMP_MSG_H__
+#define __LWIP_SNMP_MSG_H__
+
+#include "lwip/opt.h"
+#include "lwip/snmp.h"
+#include "lwip/snmp_structs.h"
+#include "lwip/ip_addr.h"
+#include "lwip/err.h"
+
+#if LWIP_SNMP
+
+#if SNMP_PRIVATE_MIB
+/* When using a private MIB, you have to create a file 'private_mib.h' that contains
+ * a 'struct mib_array_node mib_private' which contains your MIB. */
+#include "private_mib.h"
+#endif
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* The listen port of the SNMP agent. Clients have to make their requests to
+   this port. Most standard clients won't work if you change this! */
+#ifndef SNMP_IN_PORT
+#define SNMP_IN_PORT 161
+#endif
+/* The remote port the SNMP agent sends traps to. Most standard trap sinks won't
+   work if you change this! */
+#ifndef SNMP_TRAP_PORT
+#define SNMP_TRAP_PORT 162
+#endif
+
+#define SNMP_ES_NOERROR 0
+#define SNMP_ES_TOOBIG 1
+#define SNMP_ES_NOSUCHNAME 2
+#define SNMP_ES_BADVALUE 3
+#define SNMP_ES_READONLY 4
+#define SNMP_ES_GENERROR 5
+
+#define SNMP_GENTRAP_COLDSTART 0
+#define SNMP_GENTRAP_WARMSTART 1
+#define SNMP_GENTRAP_AUTHFAIL 4
+#define SNMP_GENTRAP_ENTERPRISESPC 6
+
+struct snmp_varbind
+{
+  /* next pointer, NULL for last in list */
+  struct snmp_varbind *next;
+  /* previous pointer, NULL for first in list */
+  struct snmp_varbind *prev;
+
+  /* object identifier length (in s32_t) */
+  u8_t ident_len;
+  /* object identifier array */
+  s32_t *ident;
+
+  /* object value ASN1 type */
+  u8_t value_type;
+  /* object value length (in u8_t) */
+  u8_t value_len;
+  /* object value */
+  void *value;
+
+  /* encoding varbind seq length length */
+  u8_t seqlenlen;
+  /* encoding object identifier length length */
+  u8_t olenlen;
+  /* encoding object value length length */
+  u8_t vlenlen;
+  /* encoding varbind seq length */
+  u16_t seqlen;
+  /* encoding object identifier length */
+  u16_t olen;
+  /* encoding object value length */
+  u16_t vlen;
+};
+
+struct snmp_varbind_root
+{
+  struct snmp_varbind *head;
+  struct snmp_varbind *tail;
+  /* number of variable bindings in list */
+  u8_t count;
+  /* encoding varbind-list seq length length */
+  u8_t seqlenlen;
+  /* encoding varbind-list seq length */
+  u16_t seqlen;
+};
+
+/** output response message header length fields */
+struct snmp_resp_header_lengths
+{
+  /* encoding error-index length length */
+  u8_t erridxlenlen;
+  /* encoding error-status length length */
+  u8_t errstatlenlen;
+  /* encoding request id length length */
+  u8_t ridlenlen;
+  /* encoding pdu length length */
+  u8_t pdulenlen;
+  /* encoding community length length */
+  u8_t comlenlen;
+  /* encoding version length length */
+  u8_t verlenlen;
+  /* encoding sequence length length */
+  u8_t seqlenlen;
+
+  /* encoding error-index length */
+  u16_t erridxlen;
+  /* encoding error-status length */
+  u16_t errstatlen;
+  /* encoding request id length */
+  u16_t ridlen;
+  /* encoding pdu length */
+  u16_t pdulen;
+  /* encoding community length */
+  u16_t comlen;
+  /* encoding version length */
+  u16_t verlen;
+  /* encoding sequence length */
+  u16_t seqlen;
+};
+
+/** output response message header length fields */
+struct snmp_trap_header_lengths
+{
+  /* encoding timestamp length length */
+  u8_t tslenlen;
+  /* encoding specific-trap length length */
+  u8_t strplenlen;
+  /* encoding generic-trap length length */
+  u8_t gtrplenlen;
+  /* encoding agent-addr length length */
+  u8_t aaddrlenlen;
+  /* encoding enterprise-id length length */
+  u8_t eidlenlen;
+  /* encoding pdu length length */
+  u8_t pdulenlen;
+  /* encoding community length length */
+  u8_t comlenlen;
+  /* encoding version length length */
+  u8_t verlenlen;
+  /* encoding sequence length length */
+  u8_t seqlenlen;
+
+  /* encoding timestamp length */
+  u16_t tslen;
+  /* encoding specific-trap length */
+  u16_t strplen;
+  /* encoding generic-trap length */
+  u16_t gtrplen;
+  /* encoding agent-addr length */
+  u16_t aaddrlen;
+  /* encoding enterprise-id length */
+  u16_t eidlen;
+  /* encoding pdu length */
+  u16_t pdulen;
+  /* encoding community length */
+  u16_t comlen;
+  /* encoding version length */
+  u16_t verlen;
+  /* encoding sequence length */
+  u16_t seqlen;
+};
+
+/* Accepting new SNMP messages. */
+#define SNMP_MSG_EMPTY                 0
+/* Search for matching object for variable binding. */
+#define SNMP_MSG_SEARCH_OBJ            1
+/* Perform SNMP operation on in-memory object.
+   Pass-through states, for symmetry only. */
+#define SNMP_MSG_INTERNAL_GET_OBJDEF   2
+#define SNMP_MSG_INTERNAL_GET_VALUE    3
+#define SNMP_MSG_INTERNAL_SET_TEST     4
+#define SNMP_MSG_INTERNAL_GET_OBJDEF_S 5
+#define SNMP_MSG_INTERNAL_SET_VALUE    6
+/* Perform SNMP operation on object located externally.
+   In theory this could be used for building a proxy agent.
+   Practical use is for an enterprise spc. app. gateway. */
+#define SNMP_MSG_EXTERNAL_GET_OBJDEF   7
+#define SNMP_MSG_EXTERNAL_GET_VALUE    8
+#define SNMP_MSG_EXTERNAL_SET_TEST     9
+#define SNMP_MSG_EXTERNAL_GET_OBJDEF_S 10
+#define SNMP_MSG_EXTERNAL_SET_VALUE    11
+
+#define SNMP_COMMUNITY_STR_LEN 64
+struct snmp_msg_pstat
+{
+  /* lwIP local port (161) binding */
+  struct udp_pcb *pcb;
+  /* source IP address */
+  ip_addr_t sip;
+  /* source UDP port */
+  u16_t sp;
+  /* request type */
+  u8_t rt;
+  /* request ID */
+  s32_t rid;
+  /* error status */
+  s32_t error_status;
+  /* error index */
+  s32_t error_index;
+  /* community name (zero terminated) */
+  u8_t community[SNMP_COMMUNITY_STR_LEN + 1];
+  /* community string length (exclusive zero term) */
+  u8_t com_strlen;
+  /* one out of MSG_EMPTY, MSG_DEMUX, MSG_INTERNAL, MSG_EXTERNAL_x */
+  u8_t state;
+  /* saved arguments for MSG_EXTERNAL_x */
+  struct mib_external_node *ext_mib_node;
+  struct snmp_name_ptr ext_name_ptr;
+  struct obj_def ext_object_def;
+  struct snmp_obj_id ext_oid;
+  /* index into input variable binding list */
+  u8_t vb_idx;
+  /* ptr into input variable binding list */
+  struct snmp_varbind *vb_ptr;
+  /* list of variable bindings from input */
+  struct snmp_varbind_root invb;
+  /* list of variable bindings to output */
+  struct snmp_varbind_root outvb;
+  /* output response lengths used in ASN encoding */
+  struct snmp_resp_header_lengths rhl;
+};
+
+struct snmp_msg_trap
+{
+  /* lwIP local port (161) binding */
+  struct udp_pcb *pcb;
+  /* destination IP address in network order */
+  ip_addr_t dip;
+
+  /* source enterprise ID (sysObjectID) */
+  struct snmp_obj_id *enterprise;
+  /* source IP address, raw network order format */
+  u8_t sip_raw[4];
+  /* generic trap code */
+  u32_t gen_trap;
+  /* specific trap code */
+  u32_t spc_trap;
+  /* timestamp */
+  u32_t ts;
+  /* list of variable bindings to output */
+  struct snmp_varbind_root outvb;
+  /* output trap lengths used in ASN encoding */
+  struct snmp_trap_header_lengths thl;
+};
+
+/** Agent Version constant, 0 = v1 oddity */
+extern const s32_t snmp_version;
+/** Agent default "public" community string */
+extern const char snmp_publiccommunity[7];
+
+extern struct snmp_msg_trap trap_msg;
+
+/** Agent setup, start listening to port 161. */
+void snmp_init(void);
+void snmp_trap_dst_enable(u8_t dst_idx, u8_t enable);
+void snmp_trap_dst_ip_set(u8_t dst_idx, ip_addr_t *dst);
+
+/** Varbind-list functions. */
+struct snmp_varbind* snmp_varbind_alloc(struct snmp_obj_id *oid, u8_t type, u8_t len);
+void snmp_varbind_free(struct snmp_varbind *vb);
+void snmp_varbind_list_free(struct snmp_varbind_root *root);
+void snmp_varbind_tail_add(struct snmp_varbind_root *root, struct snmp_varbind *vb);
+struct snmp_varbind* snmp_varbind_tail_remove(struct snmp_varbind_root *root);
+
+/** Handle an internal (recv) or external (private response) event. */
+void snmp_msg_event(u8_t request_id);
+err_t snmp_send_response(struct snmp_msg_pstat *m_stat);
+err_t snmp_send_trap(s8_t generic_trap, struct snmp_obj_id *eoid, s32_t specific_trap);
+void snmp_coldstart_trap(void);
+void snmp_authfail_trap(void);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* LWIP_SNMP */
+
+#endif /* __LWIP_SNMP_MSG_H__ */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/include/lwip/snmp_structs.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,268 @@
+/**
+ * @file
+ * Generic MIB tree structures.
+ *
+ * @todo namespace prefixes
+ */
+
+/*
+ * Copyright (c) 2006 Axon Digital Design B.V., The Netherlands.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * Author: Christiaan Simons <christiaan.simons@axon.tv>
+ */
+
+#ifndef __LWIP_SNMP_STRUCTS_H__
+#define __LWIP_SNMP_STRUCTS_H__
+
+#include "lwip/opt.h"
+
+#if LWIP_SNMP /* don't build if not configured for use in lwipopts.h */
+
+#include "lwip/snmp.h"
+
+#if SNMP_PRIVATE_MIB
+/* When using a private MIB, you have to create a file 'private_mib.h' that contains
+ * a 'struct mib_array_node mib_private' which contains your MIB. */
+#include "private_mib.h"
+#endif
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* MIB object instance */
+#define MIB_OBJECT_NONE 0 
+#define MIB_OBJECT_SCALAR 1
+#define MIB_OBJECT_TAB 2
+
+/* MIB access types */
+#define MIB_ACCESS_READ   1
+#define MIB_ACCESS_WRITE  2
+
+/* MIB object access */
+#define MIB_OBJECT_READ_ONLY      MIB_ACCESS_READ
+#define MIB_OBJECT_READ_WRITE     (MIB_ACCESS_READ | MIB_ACCESS_WRITE)
+#define MIB_OBJECT_WRITE_ONLY     MIB_ACCESS_WRITE
+#define MIB_OBJECT_NOT_ACCESSIBLE 0
+
+/** object definition returned by (get_object_def)() */
+struct obj_def
+{
+  /* MIB_OBJECT_NONE (0), MIB_OBJECT_SCALAR (1), MIB_OBJECT_TAB (2) */
+  u8_t instance;
+  /* 0 read-only, 1 read-write, 2 write-only, 3 not-accessible */
+  u8_t access;
+  /* ASN type for this object */
+  u8_t asn_type;
+  /* value length (host length) */
+  u16_t v_len;
+  /* length of instance part of supplied object identifier */
+  u8_t  id_inst_len;
+  /* instance part of supplied object identifier */
+  s32_t *id_inst_ptr;
+};
+
+struct snmp_name_ptr
+{
+  u8_t ident_len;
+  s32_t *ident;
+};
+
+/** MIB const scalar (.0) node */
+#define MIB_NODE_SC 0x01
+/** MIB const array node */
+#define MIB_NODE_AR 0x02
+/** MIB array node (mem_malloced from RAM) */
+#define MIB_NODE_RA 0x03
+/** MIB list root node (mem_malloced from RAM) */
+#define MIB_NODE_LR 0x04
+/** MIB node for external objects */
+#define MIB_NODE_EX 0x05
+
+/** node "base class" layout, the mandatory fields for a node  */
+struct mib_node
+{
+  /** returns struct obj_def for the given object identifier */
+  void (*get_object_def)(u8_t ident_len, s32_t *ident, struct obj_def *od);
+  /** returns object value for the given object identifier,
+     @note the caller must allocate at least len bytes for the value */
+  void (*get_value)(struct obj_def *od, u16_t len, void *value);
+  /** tests length and/or range BEFORE setting */
+  u8_t (*set_test)(struct obj_def *od, u16_t len, void *value);
+  /** sets object value, only to be called when set_test()  */
+  void (*set_value)(struct obj_def *od, u16_t len, void *value);  
+  /** One out of MIB_NODE_AR, MIB_NODE_LR or MIB_NODE_EX */
+  u8_t node_type;
+  /* array or max list length */
+  u16_t maxlength;
+};
+
+/** derived node for scalars .0 index */
+typedef struct mib_node mib_scalar_node;
+
+/** derived node, points to a fixed size const array
+    of sub-identifiers plus a 'child' pointer */
+struct mib_array_node
+{
+  /* inherited "base class" members */
+  void (*get_object_def)(u8_t ident_len, s32_t *ident, struct obj_def *od);
+  void (*get_value)(struct obj_def *od, u16_t len, void *value);
+  u8_t (*set_test)(struct obj_def *od, u16_t len, void *value);
+  void (*set_value)(struct obj_def *od, u16_t len, void *value);
+
+  u8_t node_type;
+  u16_t maxlength;
+
+  /* additional struct members */
+  const s32_t *objid;
+  struct mib_node* const *nptr;
+};
+
+/** derived node, points to a fixed size mem_malloced array
+    of sub-identifiers plus a 'child' pointer */
+struct mib_ram_array_node
+{
+  /* inherited "base class" members */
+  void (*get_object_def)(u8_t ident_len, s32_t *ident, struct obj_def *od);
+  void (*get_value)(struct obj_def *od, u16_t len, void *value);
+  u8_t (*set_test)(struct obj_def *od, u16_t len, void *value);
+  void (*set_value)(struct obj_def *od, u16_t len, void *value);
+
+  u8_t node_type;
+  u16_t maxlength;
+
+  /* aditional struct members */
+  s32_t *objid;
+  struct mib_node **nptr;
+};
+
+struct mib_list_node
+{
+  struct mib_list_node *prev;  
+  struct mib_list_node *next;
+  s32_t objid;
+  struct mib_node *nptr;
+};
+
+/** derived node, points to a doubly linked list
+    of sub-identifiers plus a 'child' pointer */
+struct mib_list_rootnode
+{
+  /* inherited "base class" members */
+  void (*get_object_def)(u8_t ident_len, s32_t *ident, struct obj_def *od);
+  void (*get_value)(struct obj_def *od, u16_t len, void *value);
+  u8_t (*set_test)(struct obj_def *od, u16_t len, void *value);
+  void (*set_value)(struct obj_def *od, u16_t len, void *value);
+
+  u8_t node_type;
+  u16_t maxlength;
+
+  /* additional struct members */
+  struct mib_list_node *head;
+  struct mib_list_node *tail;
+  /* counts list nodes in list  */
+  u16_t count;
+};
+
+/** derived node, has access functions for mib object in external memory or device
+    using 'tree_level' and 'idx', with a range 0 .. (level_length() - 1) */
+struct mib_external_node
+{
+  /* inherited "base class" members */
+  void (*get_object_def)(u8_t ident_len, s32_t *ident, struct obj_def *od);
+  void (*get_value)(struct obj_def *od, u16_t len, void *value);
+  u8_t (*set_test)(struct obj_def *od, u16_t len, void *value);
+  void (*set_value)(struct obj_def *od, u16_t len, void *value);
+
+  u8_t node_type;
+  u16_t maxlength;
+
+  /* additional struct members */
+  /** points to an external (in memory) record of some sort of addressing
+      information, passed to and interpreted by the funtions below */
+  void* addr_inf;
+  /** tree levels under this node */
+  u8_t tree_levels;
+  /** number of objects at this level */
+  u16_t (*level_length)(void* addr_inf, u8_t level);
+  /** compares object sub identifier with external id
+      return zero when equal, nonzero when unequal */
+  s32_t (*ident_cmp)(void* addr_inf, u8_t level, u16_t idx, s32_t sub_id);
+  void (*get_objid)(void* addr_inf, u8_t level, u16_t idx, s32_t *sub_id);
+
+  /** async Questions */
+  void (*get_object_def_q)(void* addr_inf, u8_t rid, u8_t ident_len, s32_t *ident);
+  void (*get_value_q)(u8_t rid, struct obj_def *od);
+  void (*set_test_q)(u8_t rid, struct obj_def *od);
+  void (*set_value_q)(u8_t rid, struct obj_def *od, u16_t len, void *value);
+  /** async Answers */
+  void (*get_object_def_a)(u8_t rid, u8_t ident_len, s32_t *ident, struct obj_def *od);
+  void (*get_value_a)(u8_t rid, struct obj_def *od, u16_t len, void *value);
+  u8_t (*set_test_a)(u8_t rid, struct obj_def *od, u16_t len, void *value);
+  void (*set_value_a)(u8_t rid, struct obj_def *od, u16_t len, void *value);
+  /** async Panic Close (agent returns error reply, 
+      e.g. used for external transaction cleanup) */
+  void (*get_object_def_pc)(u8_t rid, u8_t ident_len, s32_t *ident);
+  void (*get_value_pc)(u8_t rid, struct obj_def *od);
+  void (*set_test_pc)(u8_t rid, struct obj_def *od);
+  void (*set_value_pc)(u8_t rid, struct obj_def *od);
+};
+
+/** export MIB tree from mib2.c */
+extern const struct mib_array_node internet;
+
+/** dummy function pointers for non-leaf MIB nodes from mib2.c */
+void noleafs_get_object_def(u8_t ident_len, s32_t *ident, struct obj_def *od);
+void noleafs_get_value(struct obj_def *od, u16_t len, void *value);
+u8_t noleafs_set_test(struct obj_def *od, u16_t len, void *value);
+void noleafs_set_value(struct obj_def *od, u16_t len, void *value);
+
+void snmp_oidtoip(s32_t *ident, ip_addr_t *ip);
+void snmp_iptooid(ip_addr_t *ip, s32_t *ident);
+void snmp_ifindextonetif(s32_t ifindex, struct netif **netif);
+void snmp_netiftoifindex(struct netif *netif, s32_t *ifidx);
+
+struct mib_list_node* snmp_mib_ln_alloc(s32_t id);
+void snmp_mib_ln_free(struct mib_list_node *ln);
+struct mib_list_rootnode* snmp_mib_lrn_alloc(void);
+void snmp_mib_lrn_free(struct mib_list_rootnode *lrn);
+
+s8_t snmp_mib_node_insert(struct mib_list_rootnode *rn, s32_t objid, struct mib_list_node **insn);
+s8_t snmp_mib_node_find(struct mib_list_rootnode *rn, s32_t objid, struct mib_list_node **fn);
+struct mib_list_rootnode *snmp_mib_node_delete(struct mib_list_rootnode *rn, struct mib_list_node *n);
+
+struct mib_node* snmp_search_tree(struct mib_node *node, u8_t ident_len, s32_t *ident, struct snmp_name_ptr *np);
+struct mib_node* snmp_expand_tree(struct mib_node *node, u8_t ident_len, s32_t *ident, struct snmp_obj_id *oidret);
+u8_t snmp_iso_prefix_tst(u8_t ident_len, s32_t *ident);
+u8_t snmp_iso_prefix_expand(u8_t ident_len, s32_t *ident, struct snmp_obj_id *oidret);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* LWIP_SNMP */
+
+#endif /* __LWIP_SNMP_STRUCTS_H__ */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/include/lwip/sockets.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,376 @@
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+
+
+#ifndef __LWIP_SOCKETS_H__
+#define __LWIP_SOCKETS_H__
+
+#include "lwip/opt.h"
+
+#if LWIP_SOCKET /* don't build if not configured for use in lwipopts.h */
+
+#include <stddef.h> /* for size_t */
+
+#include "lwip/ip_addr.h"
+#include "lwip/inet.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* members are in network byte order */
+struct sockaddr_in {
+  u8_t sin_len;
+  u8_t sin_family;
+  u16_t sin_port;
+  struct in_addr sin_addr;
+  char sin_zero[8];
+};
+
+struct sockaddr {
+  u8_t sa_len;
+  u8_t sa_family;
+  u16_t sa_data[14];
+};
+
+#ifndef socklen_t
+#  define socklen_t u32_t
+#endif
+
+/* Socket protocol types (TCP/UDP/RAW) */
+#define SOCK_STREAM     1
+#define SOCK_DGRAM      2
+#define SOCK_RAW        3
+
+/*
+ * Option flags per-socket. These must match the SOF_ flags in ip.h (checked in init.c)
+ */
+#define  SO_DEBUG       0x0001 /* Unimplemented: turn on debugging info recording */
+#define  SO_ACCEPTCONN  0x0002 /* socket has had listen() */
+#define  SO_REUSEADDR   0x0004 /* Allow local address reuse */
+#define  SO_KEEPALIVE   0x0008 /* keep connections alive */
+#define  SO_DONTROUTE   0x0010 /* Unimplemented: just use interface addresses */
+#define  SO_BROADCAST   0x0020 /* permit to send and to receive broadcast messages (see IP_SOF_BROADCAST option) */
+#define  SO_USELOOPBACK 0x0040 /* Unimplemented: bypass hardware when possible */
+#define  SO_LINGER      0x0080 /* linger on close if data present */
+#define  SO_OOBINLINE   0x0100 /* Unimplemented: leave received OOB data in line */
+#define  SO_REUSEPORT   0x0200 /* Unimplemented: allow local address & port reuse */
+
+#define SO_DONTLINGER   ((int)(~SO_LINGER))
+
+/*
+ * Additional options, not kept in so_options.
+ */
+#define SO_SNDBUF    0x1001    /* Unimplemented: send buffer size */
+#define SO_RCVBUF    0x1002    /* receive buffer size */
+#define SO_SNDLOWAT  0x1003    /* Unimplemented: send low-water mark */
+#define SO_RCVLOWAT  0x1004    /* Unimplemented: receive low-water mark */
+#define SO_SNDTIMEO  0x1005    /* Unimplemented: send timeout */
+#define SO_RCVTIMEO  0x1006    /* receive timeout */
+#define SO_ERROR     0x1007    /* get error status and clear */
+#define SO_TYPE      0x1008    /* get socket type */
+#define SO_CONTIMEO  0x1009    /* Unimplemented: connect timeout */
+#define SO_NO_CHECK  0x100a    /* don't create UDP checksum */
+
+
+/*
+ * Structure used for manipulating linger option.
+ */
+struct linger {
+       int l_onoff;                /* option on/off */
+       int l_linger;               /* linger time */
+};
+
+/*
+ * Level number for (get/set)sockopt() to apply to socket itself.
+ */
+#define  SOL_SOCKET  0xfff    /* options for socket level */
+
+
+#define AF_UNSPEC       0
+#define AF_INET         2
+#define PF_INET         AF_INET
+#define PF_UNSPEC       AF_UNSPEC
+
+#define IPPROTO_IP      0
+#define IPPROTO_TCP     6
+#define IPPROTO_UDP     17
+#define IPPROTO_UDPLITE 136
+
+/* Flags we can use with send and recv. */
+#define MSG_PEEK       0x01    /* Peeks at an incoming message */
+#define MSG_WAITALL    0x02    /* Unimplemented: Requests that the function block until the full amount of data requested can be returned */
+#define MSG_OOB        0x04    /* Unimplemented: Requests out-of-band data. The significance and semantics of out-of-band data are protocol-specific */
+#define MSG_DONTWAIT   0x08    /* Nonblocking i/o for this operation only */
+#define MSG_MORE       0x10    /* Sender will send more */
+
+
+/*
+ * Options for level IPPROTO_IP
+ */
+#define IP_TOS             1
+#define IP_TTL             2
+
+#if LWIP_TCP
+/*
+ * Options for level IPPROTO_TCP
+ */
+#define TCP_NODELAY    0x01    /* don't delay send to coalesce packets */
+#define TCP_KEEPALIVE  0x02    /* send KEEPALIVE probes when idle for pcb->keep_idle milliseconds */
+#define TCP_KEEPIDLE   0x03    /* set pcb->keep_idle  - Same as TCP_KEEPALIVE, but use seconds for get/setsockopt */
+#define TCP_KEEPINTVL  0x04    /* set pcb->keep_intvl - Use seconds for get/setsockopt */
+#define TCP_KEEPCNT    0x05    /* set pcb->keep_cnt   - Use number of probes sent for get/setsockopt */
+#endif /* LWIP_TCP */
+
+#if LWIP_UDP && LWIP_UDPLITE
+/*
+ * Options for level IPPROTO_UDPLITE
+ */
+#define UDPLITE_SEND_CSCOV 0x01 /* sender checksum coverage */
+#define UDPLITE_RECV_CSCOV 0x02 /* minimal receiver checksum coverage */
+#endif /* LWIP_UDP && LWIP_UDPLITE*/
+
+
+#if LWIP_IGMP
+/*
+ * Options and types for UDP multicast traffic handling
+ */
+#define IP_ADD_MEMBERSHIP  3
+#define IP_DROP_MEMBERSHIP 4
+#define IP_MULTICAST_TTL   5
+#define IP_MULTICAST_IF    6
+#define IP_MULTICAST_LOOP  7
+
+typedef struct ip_mreq {
+    struct in_addr imr_multiaddr; /* IP multicast address of group */
+    struct in_addr imr_interface; /* local IP address of interface */
+} ip_mreq;
+#endif /* LWIP_IGMP */
+
+/*
+ * The Type of Service provides an indication of the abstract
+ * parameters of the quality of service desired.  These parameters are
+ * to be used to guide the selection of the actual service parameters
+ * when transmitting a datagram through a particular network.  Several
+ * networks offer service precedence, which somehow treats high
+ * precedence traffic as more important than other traffic (generally
+ * by accepting only traffic above a certain precedence at time of high
+ * load).  The major choice is a three way tradeoff between low-delay,
+ * high-reliability, and high-throughput.
+ * The use of the Delay, Throughput, and Reliability indications may
+ * increase the cost (in some sense) of the service.  In many networks
+ * better performance for one of these parameters is coupled with worse
+ * performance on another.  Except for very unusual cases at most two
+ * of these three indications should be set.
+ */
+#define IPTOS_TOS_MASK          0x1E
+#define IPTOS_TOS(tos)          ((tos) & IPTOS_TOS_MASK)
+#define IPTOS_LOWDELAY          0x10
+#define IPTOS_THROUGHPUT        0x08
+#define IPTOS_RELIABILITY       0x04
+#define IPTOS_LOWCOST           0x02
+#define IPTOS_MINCOST           IPTOS_LOWCOST
+
+/*
+ * The Network Control precedence designation is intended to be used
+ * within a network only.  The actual use and control of that
+ * designation is up to each network. The Internetwork Control
+ * designation is intended for use by gateway control originators only.
+ * If the actual use of these precedence designations is of concern to
+ * a particular network, it is the responsibility of that network to
+ * control the access to, and use of, those precedence designations.
+ */
+#define IPTOS_PREC_MASK                 0xe0
+#define IPTOS_PREC(tos)                ((tos) & IPTOS_PREC_MASK)
+#define IPTOS_PREC_NETCONTROL           0xe0
+#define IPTOS_PREC_INTERNETCONTROL      0xc0
+#define IPTOS_PREC_CRITIC_ECP           0xa0
+#define IPTOS_PREC_FLASHOVERRIDE        0x80
+#define IPTOS_PREC_FLASH                0x60
+#define IPTOS_PREC_IMMEDIATE            0x40
+#define IPTOS_PREC_PRIORITY             0x20
+#define IPTOS_PREC_ROUTINE              0x00
+
+
+/*
+ * Commands for ioctlsocket(),  taken from the BSD file fcntl.h.
+ * lwip_ioctl only supports FIONREAD and FIONBIO, for now
+ *
+ * Ioctl's have the command encoded in the lower word,
+ * and the size of any in or out parameters in the upper
+ * word.  The high 2 bits of the upper word are used
+ * to encode the in/out status of the parameter; for now
+ * we restrict parameters to at most 128 bytes.
+ */
+#if !defined(FIONREAD) || !defined(FIONBIO)
+#define IOCPARM_MASK    0x7fU           /* parameters must be < 128 bytes */
+#define IOC_VOID        0x20000000UL    /* no parameters */
+#define IOC_OUT         0x40000000UL    /* copy out parameters */
+#define IOC_IN          0x80000000UL    /* copy in parameters */
+#define IOC_INOUT       (IOC_IN|IOC_OUT)
+                                        /* 0x20000000 distinguishes new &
+                                           old ioctl's */
+#define _IO(x,y)        (IOC_VOID|((x)<<8)|(y))
+
+#define _IOR(x,y,t)     (IOC_OUT|(((long)sizeof(t)&IOCPARM_MASK)<<16)|((x)<<8)|(y))
+
+#define _IOW(x,y,t)     (IOC_IN|(((long)sizeof(t)&IOCPARM_MASK)<<16)|((x)<<8)|(y))
+#endif /* !defined(FIONREAD) || !defined(FIONBIO) */
+
+#ifndef FIONREAD
+#define FIONREAD    _IOR('f', 127, unsigned long) /* get # bytes to read */
+#endif
+#ifndef FIONBIO
+#define FIONBIO     _IOW('f', 126, unsigned long) /* set/clear non-blocking i/o */
+#endif
+
+/* Socket I/O Controls: unimplemented */
+#ifndef SIOCSHIWAT
+#define SIOCSHIWAT  _IOW('s',  0, unsigned long)  /* set high watermark */
+#define SIOCGHIWAT  _IOR('s',  1, unsigned long)  /* get high watermark */
+#define SIOCSLOWAT  _IOW('s',  2, unsigned long)  /* set low watermark */
+#define SIOCGLOWAT  _IOR('s',  3, unsigned long)  /* get low watermark */
+#define SIOCATMARK  _IOR('s',  7, unsigned long)  /* at oob mark? */
+#endif
+
+/* commands for fnctl */
+#ifndef F_GETFL
+#define F_GETFL 3
+#endif
+#ifndef F_SETFL
+#define F_SETFL 4
+#endif
+
+/* File status flags and file access modes for fnctl,
+   these are bits in an int. */
+#ifndef O_NONBLOCK
+#define O_NONBLOCK  1 /* nonblocking I/O */
+#endif
+#ifndef O_NDELAY
+#define O_NDELAY    1 /* same as O_NONBLOCK, for compatibility */
+#endif
+
+#ifndef SHUT_RD
+  #define SHUT_RD   1
+  #define SHUT_WR   2
+  #define SHUT_RDWR 3
+#endif
+
+/* FD_SET used for lwip_select */
+#ifndef FD_SET
+  #undef  FD_SETSIZE
+  /* Make FD_SETSIZE match NUM_SOCKETS in socket.c */
+  #define FD_SETSIZE    MEMP_NUM_NETCONN
+  #define FD_SET(n, p)  ((p)->fd_bits[(n)/8] |=  (1 << ((n) & 7)))
+  #define FD_CLR(n, p)  ((p)->fd_bits[(n)/8] &= ~(1 << ((n) & 7)))
+  #define FD_ISSET(n,p) ((p)->fd_bits[(n)/8] &   (1 << ((n) & 7)))
+  #define FD_ZERO(p)    memset((void*)(p),0,sizeof(*(p)))
+
+  typedef struct fd_set {
+          unsigned char fd_bits [(FD_SETSIZE+7)/8];
+        } fd_set;
+
+#endif /* FD_SET */
+
+/** LWIP_TIMEVAL_PRIVATE: if you want to use the struct timeval provided
+ * by your system, set this to 0 and include <sys/time.h> in cc.h */ 
+#ifndef LWIP_TIMEVAL_PRIVATE
+#define LWIP_TIMEVAL_PRIVATE 1
+#endif
+
+#if LWIP_TIMEVAL_PRIVATE
+struct timeval {
+  long    tv_sec;         /* seconds */
+  long    tv_usec;        /* and microseconds */
+};
+#endif /* LWIP_TIMEVAL_PRIVATE */
+
+void lwip_socket_init(void);
+
+int lwip_accept(int s, struct sockaddr *addr, socklen_t *addrlen);
+int lwip_bind(int s, const struct sockaddr *name, socklen_t namelen);
+int lwip_shutdown(int s, int how);
+int lwip_getpeername (int s, struct sockaddr *name, socklen_t *namelen);
+int lwip_getsockname (int s, struct sockaddr *name, socklen_t *namelen);
+int lwip_getsockopt (int s, int level, int optname, void *optval, socklen_t *optlen);
+int lwip_setsockopt (int s, int level, int optname, const void *optval, socklen_t optlen);
+int lwip_close(int s);
+int lwip_connect(int s, const struct sockaddr *name, socklen_t namelen);
+int lwip_listen(int s, int backlog);
+int lwip_recv(int s, void *mem, size_t len, int flags);
+int lwip_read(int s, void *mem, size_t len);
+int lwip_recvfrom(int s, void *mem, size_t len, int flags,
+      struct sockaddr *from, socklen_t *fromlen);
+int lwip_send(int s, const void *dataptr, size_t size, int flags);
+int lwip_sendto(int s, const void *dataptr, size_t size, int flags,
+    const struct sockaddr *to, socklen_t tolen);
+int lwip_socket(int domain, int type, int protocol);
+int lwip_write(int s, const void *dataptr, size_t size);
+int lwip_select(int maxfdp1, fd_set *readset, fd_set *writeset, fd_set *exceptset,
+                struct timeval *timeout);
+int lwip_ioctl(int s, long cmd, void *argp);
+int lwip_fcntl(int s, int cmd, int val);
+
+#if LWIP_COMPAT_SOCKETS
+#define accept(a,b,c)         lwip_accept(a,b,c)
+#define bind(a,b,c)           lwip_bind(a,b,c)
+#define shutdown(a,b)         lwip_shutdown(a,b)
+#define closesocket(s)        lwip_close(s)
+#define connect(a,b,c)        lwip_connect(a,b,c)
+#define getsockname(a,b,c)    lwip_getsockname(a,b,c)
+#define getpeername(a,b,c)    lwip_getpeername(a,b,c)
+#define setsockopt(a,b,c,d,e) lwip_setsockopt(a,b,c,d,e)
+#define getsockopt(a,b,c,d,e) lwip_getsockopt(a,b,c,d,e)
+#define listen(a,b)           lwip_listen(a,b)
+#define recv(a,b,c,d)         lwip_recv(a,b,c,d)
+#define recvfrom(a,b,c,d,e,f) lwip_recvfrom(a,b,c,d,e,f)
+#define send(a,b,c,d)         lwip_send(a,b,c,d)
+#define sendto(a,b,c,d,e,f)   lwip_sendto(a,b,c,d,e,f)
+#define socket(a,b,c)         lwip_socket(a,b,c)
+#define select(a,b,c,d,e)     lwip_select(a,b,c,d,e)
+#define ioctlsocket(a,b,c)    lwip_ioctl(a,b,c)
+
+#if LWIP_POSIX_SOCKETS_IO_NAMES
+#define read(a,b,c)           lwip_read(a,b,c)
+#define write(a,b,c)          lwip_write(a,b,c)
+#define close(s)              lwip_close(s)
+#endif /* LWIP_POSIX_SOCKETS_IO_NAMES */
+
+#endif /* LWIP_COMPAT_SOCKETS */
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* LWIP_SOCKET */
+
+#endif /* __LWIP_SOCKETS_H__ */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/include/lwip/stats.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,292 @@
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+#ifndef __LWIP_STATS_H__
+#define __LWIP_STATS_H__
+
+#include "lwip/opt.h"
+
+#include "lwip/mem.h"
+#include "lwip/memp.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#if LWIP_STATS
+
+#ifndef LWIP_STATS_LARGE
+#define LWIP_STATS_LARGE 0
+#endif
+
+#if LWIP_STATS_LARGE
+#define STAT_COUNTER     u32_t
+#define STAT_COUNTER_F   U32_F
+#else
+#define STAT_COUNTER     u16_t
+#define STAT_COUNTER_F   U16_F
+#endif 
+
+struct stats_proto {
+  STAT_COUNTER xmit;             /* Transmitted packets. */
+  STAT_COUNTER recv;             /* Received packets. */
+  STAT_COUNTER fw;               /* Forwarded packets. */
+  STAT_COUNTER drop;             /* Dropped packets. */
+  STAT_COUNTER chkerr;           /* Checksum error. */
+  STAT_COUNTER lenerr;           /* Invalid length error. */
+  STAT_COUNTER memerr;           /* Out of memory error. */
+  STAT_COUNTER rterr;            /* Routing error. */
+  STAT_COUNTER proterr;          /* Protocol error. */
+  STAT_COUNTER opterr;           /* Error in options. */
+  STAT_COUNTER err;              /* Misc error. */
+  STAT_COUNTER cachehit;
+};
+
+struct stats_igmp {
+  STAT_COUNTER xmit;             /* Transmitted packets. */
+  STAT_COUNTER recv;             /* Received packets. */
+  STAT_COUNTER drop;             /* Dropped packets. */
+  STAT_COUNTER chkerr;           /* Checksum error. */
+  STAT_COUNTER lenerr;           /* Invalid length error. */
+  STAT_COUNTER memerr;           /* Out of memory error. */
+  STAT_COUNTER proterr;          /* Protocol error. */
+  STAT_COUNTER rx_v1;            /* Received v1 frames. */
+  STAT_COUNTER rx_group;         /* Received group-specific queries. */
+  STAT_COUNTER rx_general;       /* Received general queries. */
+  STAT_COUNTER rx_report;        /* Received reports. */
+  STAT_COUNTER tx_join;          /* Sent joins. */
+  STAT_COUNTER tx_leave;         /* Sent leaves. */
+  STAT_COUNTER tx_report;        /* Sent reports. */
+};
+
+struct stats_mem {
+#ifdef LWIP_DEBUG
+  const char *name;
+#endif /* LWIP_DEBUG */
+  mem_size_t avail;
+  mem_size_t used;
+  mem_size_t max;
+  STAT_COUNTER err;
+  STAT_COUNTER illegal;
+};
+
+struct stats_syselem {
+  STAT_COUNTER used;
+  STAT_COUNTER max;
+  STAT_COUNTER err;
+};
+
+struct stats_sys {
+  struct stats_syselem sem;
+  struct stats_syselem mutex;
+  struct stats_syselem mbox;
+};
+
+struct stats_ {
+#if LINK_STATS
+  struct stats_proto link;
+#endif
+#if ETHARP_STATS
+  struct stats_proto etharp;
+#endif
+#if IPFRAG_STATS
+  struct stats_proto ip_frag;
+#endif
+#if IP_STATS
+  struct stats_proto ip;
+#endif
+#if ICMP_STATS
+  struct stats_proto icmp;
+#endif
+#if IGMP_STATS
+  struct stats_igmp igmp;
+#endif
+#if UDP_STATS
+  struct stats_proto udp;
+#endif
+#if TCP_STATS
+  struct stats_proto tcp;
+#endif
+#if MEM_STATS
+  struct stats_mem mem;
+#endif
+#if MEMP_STATS
+  struct stats_mem memp[MEMP_MAX];
+#endif
+#if SYS_STATS
+  struct stats_sys sys;
+#endif
+};
+
+extern struct stats_ lwip_stats;
+
+void stats_init(void);
+
+#define STATS_INC(x) ++lwip_stats.x
+#define STATS_DEC(x) --lwip_stats.x
+#define STATS_INC_USED(x, y) do { lwip_stats.x.used += y; \
+                                if (lwip_stats.x.max < lwip_stats.x.used) { \
+                                    lwip_stats.x.max = lwip_stats.x.used; \
+                                } \
+                             } while(0)
+#else /* LWIP_STATS */
+#define stats_init()
+#define STATS_INC(x)
+#define STATS_DEC(x)
+#define STATS_INC_USED(x)
+#endif /* LWIP_STATS */
+
+#if TCP_STATS
+#define TCP_STATS_INC(x) STATS_INC(x)
+#define TCP_STATS_DISPLAY() stats_display_proto(&lwip_stats.tcp, "TCP")
+#else
+#define TCP_STATS_INC(x)
+#define TCP_STATS_DISPLAY()
+#endif
+
+#if UDP_STATS
+#define UDP_STATS_INC(x) STATS_INC(x)
+#define UDP_STATS_DISPLAY() stats_display_proto(&lwip_stats.udp, "UDP")
+#else
+#define UDP_STATS_INC(x)
+#define UDP_STATS_DISPLAY()
+#endif
+
+#if ICMP_STATS
+#define ICMP_STATS_INC(x) STATS_INC(x)
+#define ICMP_STATS_DISPLAY() stats_display_proto(&lwip_stats.icmp, "ICMP")
+#else
+#define ICMP_STATS_INC(x)
+#define ICMP_STATS_DISPLAY()
+#endif
+
+#if IGMP_STATS
+#define IGMP_STATS_INC(x) STATS_INC(x)
+#define IGMP_STATS_DISPLAY() stats_display_igmp(&lwip_stats.igmp)
+#else
+#define IGMP_STATS_INC(x)
+#define IGMP_STATS_DISPLAY()
+#endif
+
+#if IP_STATS
+#define IP_STATS_INC(x) STATS_INC(x)
+#define IP_STATS_DISPLAY() stats_display_proto(&lwip_stats.ip, "IP")
+#else
+#define IP_STATS_INC(x)
+#define IP_STATS_DISPLAY()
+#endif
+
+#if IPFRAG_STATS
+#define IPFRAG_STATS_INC(x) STATS_INC(x)
+#define IPFRAG_STATS_DISPLAY() stats_display_proto(&lwip_stats.ip_frag, "IP_FRAG")
+#else
+#define IPFRAG_STATS_INC(x)
+#define IPFRAG_STATS_DISPLAY()
+#endif
+
+#if ETHARP_STATS
+#define ETHARP_STATS_INC(x) STATS_INC(x)
+#define ETHARP_STATS_DISPLAY() stats_display_proto(&lwip_stats.etharp, "ETHARP")
+#else
+#define ETHARP_STATS_INC(x)
+#define ETHARP_STATS_DISPLAY()
+#endif
+
+#if LINK_STATS
+#define LINK_STATS_INC(x) STATS_INC(x)
+#define LINK_STATS_DISPLAY() stats_display_proto(&lwip_stats.link, "LINK")
+#else
+#define LINK_STATS_INC(x)
+#define LINK_STATS_DISPLAY()
+#endif
+
+#if MEM_STATS
+#define MEM_STATS_AVAIL(x, y) lwip_stats.mem.x = y
+#define MEM_STATS_INC(x) STATS_INC(mem.x)
+#define MEM_STATS_INC_USED(x, y) STATS_INC_USED(mem, y)
+#define MEM_STATS_DEC_USED(x, y) lwip_stats.mem.x -= y
+#define MEM_STATS_DISPLAY() stats_display_mem(&lwip_stats.mem, "HEAP")
+#else
+#define MEM_STATS_AVAIL(x, y)
+#define MEM_STATS_INC(x)
+#define MEM_STATS_INC_USED(x, y)
+#define MEM_STATS_DEC_USED(x, y)
+#define MEM_STATS_DISPLAY()
+#endif
+
+#if MEMP_STATS
+#define MEMP_STATS_AVAIL(x, i, y) lwip_stats.memp[i].x = y
+#define MEMP_STATS_INC(x, i) STATS_INC(memp[i].x)
+#define MEMP_STATS_DEC(x, i) STATS_DEC(memp[i].x)
+#define MEMP_STATS_INC_USED(x, i) STATS_INC_USED(memp[i], 1)
+#define MEMP_STATS_DISPLAY(i) stats_display_memp(&lwip_stats.memp[i], i)
+#else
+#define MEMP_STATS_AVAIL(x, i, y)
+#define MEMP_STATS_INC(x, i)
+#define MEMP_STATS_DEC(x, i)
+#define MEMP_STATS_INC_USED(x, i)
+#define MEMP_STATS_DISPLAY(i)
+#endif
+
+#if SYS_STATS
+#define SYS_STATS_INC(x) STATS_INC(sys.x)
+#define SYS_STATS_DEC(x) STATS_DEC(sys.x)
+#define SYS_STATS_INC_USED(x) STATS_INC_USED(sys.x, 1)
+#define SYS_STATS_DISPLAY() stats_display_sys(&lwip_stats.sys)
+#else
+#define SYS_STATS_INC(x)
+#define SYS_STATS_DEC(x)
+#define SYS_STATS_INC_USED(x)
+#define SYS_STATS_DISPLAY()
+#endif
+
+/* Display of statistics */
+#if LWIP_STATS_DISPLAY
+void stats_display(void);
+void stats_display_proto(struct stats_proto *proto, char *name);
+void stats_display_igmp(struct stats_igmp *igmp);
+void stats_display_mem(struct stats_mem *mem, char *name);
+void stats_display_memp(struct stats_mem *mem, int index);
+void stats_display_sys(struct stats_sys *sys);
+#else /* LWIP_STATS_DISPLAY */
+#define stats_display()
+#define stats_display_proto(proto, name)
+#define stats_display_igmp(igmp)
+#define stats_display_mem(mem, name)
+#define stats_display_memp(mem, index)
+#define stats_display_sys(sys)
+#endif /* LWIP_STATS_DISPLAY */
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __LWIP_STATS_H__ */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/include/lwip/sys.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,331 @@
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+#ifndef __LWIP_SYS_H__
+#define __LWIP_SYS_H__
+
+#include "lwip/opt.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#if NO_SYS
+
+/* For a totally minimal and standalone system, we provide null
+   definitions of the sys_ functions. */
+typedef u8_t sys_sem_t;
+typedef u8_t sys_mutex_t;
+typedef u8_t sys_mbox_t;
+
+#define sys_sem_new(s, c) ERR_OK
+#define sys_sem_signal(s)
+#define sys_sem_wait(s)
+#define sys_arch_sem_wait(s,t)
+#define sys_sem_free(s)
+#define sys_mutex_new(mu) ERR_OK
+#define sys_mutex_lock(mu)
+#define sys_mutex_unlock(mu)
+#define sys_mutex_free(mu)
+#define sys_mbox_new(m, s) ERR_OK
+#define sys_mbox_fetch(m,d)
+#define sys_mbox_tryfetch(m,d)
+#define sys_mbox_post(m,d)
+#define sys_mbox_trypost(m,d)
+#define sys_mbox_free(m)
+
+#define sys_thread_new(n,t,a,s,p)
+
+#define sys_msleep(t)
+
+#else /* NO_SYS */
+
+/** Return code for timeouts from sys_arch_mbox_fetch and sys_arch_sem_wait */
+#define SYS_ARCH_TIMEOUT 0xffffffffUL
+
+/** sys_mbox_tryfetch() returns SYS_MBOX_EMPTY if appropriate.
+ * For now we use the same magic value, but we allow this to change in future.
+ */
+#define SYS_MBOX_EMPTY SYS_ARCH_TIMEOUT 
+
+#include "lwip/err.h"
+#include "arch/sys_arch.h"
+
+/** Function prototype for thread functions */
+typedef void (*lwip_thread_fn)(void *arg);
+
+/* Function prototypes for functions to be implemented by platform ports
+   (in sys_arch.c) */
+
+/* Mutex functions: */
+
+/** Define LWIP_COMPAT_MUTEX if the port has no mutexes and binary semaphores
+    should be used instead */
+#if LWIP_COMPAT_MUTEX
+/* for old ports that don't have mutexes: define them to binary semaphores */
+#define sys_mutex_t                   sys_sem_t
+#define sys_mutex_new(mutex)          sys_sem_new(mutex, 1)
+#define sys_mutex_lock(mutex)         sys_sem_wait(mutex)
+#define sys_mutex_unlock(mutex)       sys_sem_signal(mutex)
+#define sys_mutex_free(mutex)         sys_sem_free(mutex)
+#define sys_mutex_valid(mutex)        sys_sem_valid(mutex)
+#define sys_mutex_set_invalid(mutex)  sys_sem_set_invalid(mutex)
+
+#else /* LWIP_COMPAT_MUTEX */
+
+/** Create a new mutex
+ * @param mutex pointer to the mutex to create
+ * @return a new mutex */
+err_t sys_mutex_new(sys_mutex_t *mutex);
+/** Lock a mutex
+ * @param mutex the mutex to lock */
+void sys_mutex_lock(sys_mutex_t *mutex);
+/** Unlock a mutex
+ * @param mutex the mutex to unlock */
+void sys_mutex_unlock(sys_mutex_t *mutex);
+/** Delete a semaphore
+ * @param mutex the mutex to delete */
+void sys_mutex_free(sys_mutex_t *mutex); 
+#ifndef sys_mutex_valid
+/** Check if a mutex is valid/allocated: return 1 for valid, 0 for invalid */
+int sys_mutex_valid(sys_mutex_t *mutex);
+#endif
+#ifndef sys_mutex_set_invalid
+/** Set a mutex invalid so that sys_mutex_valid returns 0 */
+void sys_mutex_set_invalid(sys_mutex_t *mutex);
+#endif
+#endif /* LWIP_COMPAT_MUTEX */
+
+/* Semaphore functions: */
+
+/** Create a new semaphore
+ * @param sem pointer to the semaphore to create
+ * @param count initial count of the semaphore
+ * @return ERR_OK if successful, another err_t otherwise */
+err_t sys_sem_new(sys_sem_t *sem, u8_t count);
+/** Signals a semaphore
+ * @param sem the semaphore to signal */
+void sys_sem_signal(sys_sem_t *sem);
+/** Wait for a semaphore for the specified timeout
+ * @param sem the semaphore to wait for
+ * @param timeout timeout in milliseconds to wait (0 = wait forever)
+ * @return time (in milliseconds) waited for the semaphore
+ *         or SYS_ARCH_TIMEOUT on timeout */
+u32_t sys_arch_sem_wait(sys_sem_t *sem, u32_t timeout);
+/** Delete a semaphore
+ * @param sem semaphore to delete */
+void sys_sem_free(sys_sem_t *sem);
+/** Wait for a semaphore - forever/no timeout */
+#define sys_sem_wait(sem)                  sys_arch_sem_wait(sem, 0)
+#ifndef sys_sem_valid
+/** Check if a sempahore is valid/allocated: return 1 for valid, 0 for invalid */
+int sys_sem_valid(sys_sem_t *sem);
+#endif
+#ifndef sys_sem_set_invalid
+/** Set a semaphore invalid so that sys_sem_valid returns 0 */
+void sys_sem_set_invalid(sys_sem_t *sem);
+#endif
+
+/* Time functions. */
+#ifndef sys_msleep
+void sys_msleep(u32_t ms); /* only has a (close to) 1 jiffy resolution. */
+#endif
+
+/* Mailbox functions. */
+
+/** Create a new mbox of specified size
+ * @param mbox pointer to the mbox to create
+ * @param size (miminum) number of messages in this mbox
+ * @return ERR_OK if successful, another err_t otherwise */
+err_t sys_mbox_new(sys_mbox_t *mbox, int size);
+/** Post a message to an mbox - may not fail
+ * -> blocks if full, only used from tasks not from ISR
+ * @param mbox mbox to posts the message
+ * @param msg message to post (ATTENTION: can be NULL) */
+void sys_mbox_post(sys_mbox_t *mbox, void *msg);
+/** Try to post a message to an mbox - may fail if full or ISR
+ * @param mbox mbox to posts the message
+ * @param msg message to post (ATTENTION: can be NULL) */
+err_t sys_mbox_trypost(sys_mbox_t *mbox, void *msg);
+/** Wait for a new message to arrive in the mbox
+ * @param mbox mbox to get a message from
+ * @param msg pointer where the message is stored
+ * @param timeout maximum time (in milliseconds) to wait for a message
+ * @return time (in milliseconds) waited for a message, may be 0 if not waited
+           or SYS_ARCH_TIMEOUT on timeout
+ *         The returned time has to be accurate to prevent timer jitter! */
+u32_t sys_arch_mbox_fetch(sys_mbox_t *mbox, void **msg, u32_t timeout);
+/* Allow port to override with a macro, e.g. special timout for sys_arch_mbox_fetch() */
+#ifndef sys_arch_mbox_tryfetch
+/** Wait for a new message to arrive in the mbox
+ * @param mbox mbox to get a message from
+ * @param msg pointer where the message is stored
+ * @param timeout maximum time (in milliseconds) to wait for a message
+ * @return 0 (milliseconds) if a message has been received
+ *         or SYS_MBOX_EMPTY if the mailbox is empty */
+u32_t sys_arch_mbox_tryfetch(sys_mbox_t *mbox, void **msg);
+#endif
+/** For now, we map straight to sys_arch implementation. */
+#define sys_mbox_tryfetch(mbox, msg) sys_arch_mbox_tryfetch(mbox, msg)
+/** Delete an mbox
+ * @param mbox mbox to delete */
+void sys_mbox_free(sys_mbox_t *mbox);
+#define sys_mbox_fetch(mbox, msg) sys_arch_mbox_fetch(mbox, msg, 0)
+#ifndef sys_mbox_valid
+/** Check if an mbox is valid/allocated: return 1 for valid, 0 for invalid */
+int sys_mbox_valid(sys_mbox_t *mbox);
+#endif
+#ifndef sys_mbox_set_invalid
+/** Set an mbox invalid so that sys_mbox_valid returns 0 */
+void sys_mbox_set_invalid(sys_mbox_t *mbox);
+#endif
+
+/** The only thread function:
+ * Creates a new thread
+ * @param name human-readable name for the thread (used for debugging purposes)
+ * @param thread thread-function
+ * @param arg parameter passed to 'thread'
+ * @param stacksize stack size in bytes for the new thread (may be ignored by ports)
+ * @param prio priority of the new thread (may be ignored by ports) */
+sys_thread_t sys_thread_new(const char *name, lwip_thread_fn thread, void *arg, int stacksize, int prio);
+
+#endif /* NO_SYS */
+
+/* sys_init() must be called before anthing else. */
+void sys_init(void);
+
+#ifndef sys_jiffies
+/** Ticks/jiffies since power up. */
+u32_t sys_jiffies(void);
+#endif
+
+/** Returns the current time in milliseconds,
+ * may be the same as sys_jiffies or at least based on it. */
+u32_t sys_now(void);
+
+/* Critical Region Protection */
+/* These functions must be implemented in the sys_arch.c file.
+   In some implementations they can provide a more light-weight protection
+   mechanism than using semaphores. Otherwise semaphores can be used for
+   implementation */
+#ifndef SYS_ARCH_PROTECT
+/** SYS_LIGHTWEIGHT_PROT
+ * define SYS_LIGHTWEIGHT_PROT in lwipopts.h if you want inter-task protection
+ * for certain critical regions during buffer allocation, deallocation and memory
+ * allocation and deallocation.
+ */
+#if SYS_LIGHTWEIGHT_PROT
+
+/** SYS_ARCH_DECL_PROTECT
+ * declare a protection variable. This macro will default to defining a variable of
+ * type sys_prot_t. If a particular port needs a different implementation, then
+ * this macro may be defined in sys_arch.h.
+ */
+#define SYS_ARCH_DECL_PROTECT(lev) sys_prot_t lev
+/** SYS_ARCH_PROTECT
+ * Perform a "fast" protect. This could be implemented by
+ * disabling interrupts for an embedded system or by using a semaphore or
+ * mutex. The implementation should allow calling SYS_ARCH_PROTECT when
+ * already protected. The old protection level is returned in the variable
+ * "lev". This macro will default to calling the sys_arch_protect() function
+ * which should be implemented in sys_arch.c. If a particular port needs a
+ * different implementation, then this macro may be defined in sys_arch.h
+ */
+#define SYS_ARCH_PROTECT(lev) lev = sys_arch_protect()
+/** SYS_ARCH_UNPROTECT
+ * Perform a "fast" set of the protection level to "lev". This could be
+ * implemented by setting the interrupt level to "lev" within the MACRO or by
+ * using a semaphore or mutex.  This macro will default to calling the
+ * sys_arch_unprotect() function which should be implemented in
+ * sys_arch.c. If a particular port needs a different implementation, then
+ * this macro may be defined in sys_arch.h
+ */
+#define SYS_ARCH_UNPROTECT(lev) sys_arch_unprotect(lev)
+sys_prot_t sys_arch_protect(void);
+void sys_arch_unprotect(sys_prot_t pval);
+
+#else
+
+#define SYS_ARCH_DECL_PROTECT(lev)
+#define SYS_ARCH_PROTECT(lev)
+#define SYS_ARCH_UNPROTECT(lev)
+
+#endif /* SYS_LIGHTWEIGHT_PROT */
+
+#endif /* SYS_ARCH_PROTECT */
+
+/*
+ * Macros to set/get and increase/decrease variables in a thread-safe way.
+ * Use these for accessing variable that are used from more than one thread.
+ */
+
+#ifndef SYS_ARCH_INC
+#define SYS_ARCH_INC(var, val) do { \
+                                SYS_ARCH_DECL_PROTECT(old_level); \
+                                SYS_ARCH_PROTECT(old_level); \
+                                var += val; \
+                                SYS_ARCH_UNPROTECT(old_level); \
+                              } while(0)
+#endif /* SYS_ARCH_INC */
+
+#ifndef SYS_ARCH_DEC
+#define SYS_ARCH_DEC(var, val) do { \
+                                SYS_ARCH_DECL_PROTECT(old_level); \
+                                SYS_ARCH_PROTECT(old_level); \
+                                var -= val; \
+                                SYS_ARCH_UNPROTECT(old_level); \
+                              } while(0)
+#endif /* SYS_ARCH_DEC */
+
+#ifndef SYS_ARCH_GET
+#define SYS_ARCH_GET(var, ret) do { \
+                                SYS_ARCH_DECL_PROTECT(old_level); \
+                                SYS_ARCH_PROTECT(old_level); \
+                                ret = var; \
+                                SYS_ARCH_UNPROTECT(old_level); \
+                              } while(0)
+#endif /* SYS_ARCH_GET */
+
+#ifndef SYS_ARCH_SET
+#define SYS_ARCH_SET(var, val) do { \
+                                SYS_ARCH_DECL_PROTECT(old_level); \
+                                SYS_ARCH_PROTECT(old_level); \
+                                var = val; \
+                                SYS_ARCH_UNPROTECT(old_level); \
+                              } while(0)
+#endif /* SYS_ARCH_SET */
+
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __LWIP_SYS_H__ */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/include/lwip/tcp.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,377 @@
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+#ifndef __LWIP_TCP_H__
+#define __LWIP_TCP_H__
+
+#include "lwip/opt.h"
+
+#if LWIP_TCP /* don't build if not configured for use in lwipopts.h */
+
+#include "lwip/sys.h"
+#include "lwip/mem.h"
+#include "lwip/pbuf.h"
+#include "lwip/ip.h"
+#include "lwip/icmp.h"
+#include "lwip/err.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+struct tcp_pcb;
+
+/** Function prototype for tcp accept callback functions. Called when a new
+ * connection can be accepted on a listening pcb.
+ *
+ * @param arg Additional argument to pass to the callback function (@see tcp_arg())
+ * @param newpcb The new connection pcb
+ * @param err An error code if there has been an error accepting.
+ *            Only return ERR_ABRT if you have called tcp_abort from within the
+ *            callback function!
+ */
+typedef err_t (*tcp_accept_fn)(void *arg, struct tcp_pcb *newpcb, err_t err);
+
+/** Function prototype for tcp receive callback functions. Called when data has
+ * been received.
+ *
+ * @param arg Additional argument to pass to the callback function (@see tcp_arg())
+ * @param tpcb The connection pcb which received data
+ * @param p The received data (or NULL when the connection has been closed!)
+ * @param err An error code if there has been an error receiving
+ *            Only return ERR_ABRT if you have called tcp_abort from within the
+ *            callback function!
+ */
+typedef err_t (*tcp_recv_fn)(void *arg, struct tcp_pcb *tpcb,
+                             struct pbuf *p, err_t err);
+
+/** Function prototype for tcp sent callback functions. Called when sent data has
+ * been acknowledged by the remote side. Use it to free corresponding resources.
+ * This also means that the pcb has now space available to send new data.
+ *
+ * @param arg Additional argument to pass to the callback function (@see tcp_arg())
+ * @param tpcb The connection pcb for which data has been acknowledged
+ * @param len The amount of bytes acknowledged
+ * @return ERR_OK: try to send some data by calling tcp_output
+ *            Only return ERR_ABRT if you have called tcp_abort from within the
+ *            callback function!
+ */
+typedef err_t (*tcp_sent_fn)(void *arg, struct tcp_pcb *tpcb,
+                              u16_t len);
+
+/** Function prototype for tcp poll callback functions. Called periodically as
+ * specified by @see tcp_poll.
+ *
+ * @param arg Additional argument to pass to the callback function (@see tcp_arg())
+ * @param tpcb tcp pcb
+ * @return ERR_OK: try to send some data by calling tcp_output
+ *            Only return ERR_ABRT if you have called tcp_abort from within the
+ *            callback function!
+ */
+typedef err_t (*tcp_poll_fn)(void *arg, struct tcp_pcb *tpcb);
+
+/** Function prototype for tcp error callback functions. Called when the pcb
+ * receives a RST or is unexpectedly closed for any other reason.
+ *
+ * @note The corresponding pcb is already freed when this callback is called!
+ *
+ * @param arg Additional argument to pass to the callback function (@see tcp_arg())
+ * @param err Error code to indicate why the pcb has been closed
+ *            ERR_ABRT: aborted through tcp_abort or by a TCP timer
+ *            ERR_RST: the connection was reset by the remote host
+ */
+typedef void  (*tcp_err_fn)(void *arg, err_t err);
+
+/** Function prototype for tcp connected callback functions. Called when a pcb
+ * is connected to the remote side after initiating a connection attempt by
+ * calling tcp_connect().
+ *
+ * @param arg Additional argument to pass to the callback function (@see tcp_arg())
+ * @param tpcb The connection pcb which is connected
+ * @param err An unused error code, always ERR_OK currently ;-) TODO!
+ *            Only return ERR_ABRT if you have called tcp_abort from within the
+ *            callback function!
+ *
+ * @note When a connection attempt fails, the error callback is currently called!
+ */
+typedef err_t (*tcp_connected_fn)(void *arg, struct tcp_pcb *tpcb, err_t err);
+
+enum tcp_state {
+  CLOSED      = 0,
+  LISTEN      = 1,
+  SYN_SENT    = 2,
+  SYN_RCVD    = 3,
+  ESTABLISHED = 4,
+  FIN_WAIT_1  = 5,
+  FIN_WAIT_2  = 6,
+  CLOSE_WAIT  = 7,
+  CLOSING     = 8,
+  LAST_ACK    = 9,
+  TIME_WAIT   = 10
+};
+
+#if LWIP_CALLBACK_API
+  /* Function to call when a listener has been connected.
+   * @param arg user-supplied argument (tcp_pcb.callback_arg)
+   * @param pcb a new tcp_pcb that now is connected
+   * @param err an error argument (TODO: that is current always ERR_OK?)
+   * @return ERR_OK: accept the new connection,
+   *                 any other err_t abortsthe new connection
+   */
+#define DEF_ACCEPT_CALLBACK  tcp_accept_fn accept;
+#else /* LWIP_CALLBACK_API */
+#define DEF_ACCEPT_CALLBACK
+#endif /* LWIP_CALLBACK_API */
+
+/**
+ * members common to struct tcp_pcb and struct tcp_listen_pcb
+ */
+#define TCP_PCB_COMMON(type) \
+  type *next; /* for the linked list */ \
+  enum tcp_state state; /* TCP state */ \
+  u8_t prio; \
+  void *callback_arg; \
+  /* the accept callback for listen- and normal pcbs, if LWIP_CALLBACK_API */ \
+  DEF_ACCEPT_CALLBACK \
+  /* ports are in host byte order */ \
+  u16_t local_port
+
+
+/* the TCP protocol control block */
+struct tcp_pcb {
+/** common PCB members */
+  IP_PCB;
+/** protocol specific PCB members */
+  TCP_PCB_COMMON(struct tcp_pcb);
+
+  /* ports are in host byte order */
+  u16_t remote_port;
+  
+  u8_t flags;
+#define TF_ACK_DELAY   ((u8_t)0x01U)   /* Delayed ACK. */
+#define TF_ACK_NOW     ((u8_t)0x02U)   /* Immediate ACK. */
+#define TF_INFR        ((u8_t)0x04U)   /* In fast recovery. */
+#define TF_TIMESTAMP   ((u8_t)0x08U)   /* Timestamp option enabled */
+#define TF_RXCLOSED    ((u8_t)0x10U)   /* rx closed by tcp_shutdown */
+#define TF_FIN         ((u8_t)0x20U)   /* Connection was closed locally (FIN segment enqueued). */
+#define TF_NODELAY     ((u8_t)0x40U)   /* Disable Nagle algorithm */
+#define TF_NAGLEMEMERR ((u8_t)0x80U)   /* nagle enabled, memerr, try to output to prevent delayed ACK to happen */
+
+  /* the rest of the fields are in host byte order
+     as we have to do some math with them */
+  /* receiver variables */
+  u32_t rcv_nxt;   /* next seqno expected */
+  u16_t rcv_wnd;   /* receiver window available */
+  u16_t rcv_ann_wnd; /* receiver window to announce */
+  u32_t rcv_ann_right_edge; /* announced right edge of window */
+
+  /* Timers */
+  u32_t tmr;
+  u8_t polltmr, pollinterval;
+  
+  /* Retransmission timer. */
+  s16_t rtime;
+  
+  u16_t mss;   /* maximum segment size */
+  
+  /* RTT (round trip time) estimation variables */
+  u32_t rttest; /* RTT estimate in 500ms ticks */
+  u32_t rtseq;  /* sequence number being timed */
+  s16_t sa, sv; /* @todo document this */
+
+  s16_t rto;    /* retransmission time-out */
+  u8_t nrtx;    /* number of retransmissions */
+
+  /* fast retransmit/recovery */
+  u32_t lastack; /* Highest acknowledged seqno. */
+  u8_t dupacks;
+  
+  /* congestion avoidance/control variables */
+  u16_t cwnd;  
+  u16_t ssthresh;
+
+  /* sender variables */
+  u32_t snd_nxt;   /* next new seqno to be sent */
+  u16_t snd_wnd;   /* sender window */
+  u32_t snd_wl1, snd_wl2; /* Sequence and acknowledgement numbers of last
+                             window update. */
+  u32_t snd_lbb;       /* Sequence number of next byte to be buffered. */
+
+  u16_t acked;
+  
+  u16_t snd_buf;   /* Available buffer space for sending (in bytes). */
+#define TCP_SNDQUEUELEN_OVERFLOW (0xffff-3)
+  u16_t snd_queuelen; /* Available buffer space for sending (in tcp_segs). */
+
+#if TCP_OVERSIZE
+  /* Extra bytes available at the end of the last pbuf in unsent. */
+  u16_t unsent_oversize;
+#endif /* TCP_OVERSIZE */ 
+
+  /* These are ordered by sequence number: */
+  struct tcp_seg *unsent;   /* Unsent (queued) segments. */
+  struct tcp_seg *unacked;  /* Sent but unacknowledged segments. */
+#if TCP_QUEUE_OOSEQ  
+  struct tcp_seg *ooseq;    /* Received out of sequence segments. */
+#endif /* TCP_QUEUE_OOSEQ */
+
+  struct pbuf *refused_data; /* Data previously received but not yet taken by upper layer */
+
+#if LWIP_CALLBACK_API
+  /* Function to be called when more send buffer space is available. */
+  tcp_sent_fn sent;
+  /* Function to be called when (in-sequence) data has arrived. */
+  tcp_recv_fn recv;
+  /* Function to be called when a connection has been set up. */
+  tcp_connected_fn connected;
+  /* Function which is called periodically. */
+  tcp_poll_fn poll;
+  /* Function to be called whenever a fatal error occurs. */
+  tcp_err_fn errf;
+#endif /* LWIP_CALLBACK_API */
+
+#if LWIP_TCP_TIMESTAMPS
+  u32_t ts_lastacksent;
+  u32_t ts_recent;
+#endif /* LWIP_TCP_TIMESTAMPS */
+
+  /* idle time before KEEPALIVE is sent */
+  u32_t keep_idle;
+#if LWIP_TCP_KEEPALIVE
+  u32_t keep_intvl;
+  u32_t keep_cnt;
+#endif /* LWIP_TCP_KEEPALIVE */
+  
+  /* Persist timer counter */
+  u32_t persist_cnt;
+  /* Persist timer back-off */
+  u8_t persist_backoff;
+
+  /* KEEPALIVE counter */
+  u8_t keep_cnt_sent;
+};
+
+struct tcp_pcb_listen {  
+/* Common members of all PCB types */
+  IP_PCB;
+/* Protocol specific PCB members */
+  TCP_PCB_COMMON(struct tcp_pcb_listen);
+
+#if TCP_LISTEN_BACKLOG
+  u8_t backlog;
+  u8_t accepts_pending;
+#endif /* TCP_LISTEN_BACKLOG */
+};
+
+#if LWIP_EVENT_API
+
+enum lwip_event {
+  LWIP_EVENT_ACCEPT,
+  LWIP_EVENT_SENT,
+  LWIP_EVENT_RECV,
+  LWIP_EVENT_CONNECTED,
+  LWIP_EVENT_POLL,
+  LWIP_EVENT_ERR
+};
+
+err_t lwip_tcp_event(void *arg, struct tcp_pcb *pcb,
+         enum lwip_event,
+         struct pbuf *p,
+         u16_t size,
+         err_t err);
+
+#endif /* LWIP_EVENT_API */
+
+/* Application program's interface: */
+struct tcp_pcb * tcp_new     (void);
+
+void             tcp_arg     (struct tcp_pcb *pcb, void *arg);
+void             tcp_accept  (struct tcp_pcb *pcb, tcp_accept_fn accept);
+void             tcp_recv    (struct tcp_pcb *pcb, tcp_recv_fn recv);
+void             tcp_sent    (struct tcp_pcb *pcb, tcp_sent_fn sent);
+void             tcp_poll    (struct tcp_pcb *pcb, tcp_poll_fn poll, u8_t interval);
+void             tcp_err     (struct tcp_pcb *pcb, tcp_err_fn err);
+
+#define          tcp_mss(pcb)             (((pcb)->flags & TF_TIMESTAMP) ? ((pcb)->mss - 12)  : (pcb)->mss)
+#define          tcp_sndbuf(pcb)          ((pcb)->snd_buf)
+#define          tcp_sndqueuelen(pcb)     ((pcb)->snd_queuelen)
+#define          tcp_nagle_disable(pcb)   ((pcb)->flags |= TF_NODELAY)
+#define          tcp_nagle_enable(pcb)    ((pcb)->flags &= ~TF_NODELAY)
+#define          tcp_nagle_disabled(pcb)  (((pcb)->flags & TF_NODELAY) != 0)
+
+#if TCP_LISTEN_BACKLOG
+#define          tcp_accepted(pcb) do { \
+  LWIP_ASSERT("pcb->state == LISTEN (called for wrong pcb?)", pcb->state == LISTEN); \
+  (((struct tcp_pcb_listen *)(pcb))->accepts_pending--); } while(0)
+#else  /* TCP_LISTEN_BACKLOG */
+#define          tcp_accepted(pcb) LWIP_ASSERT("pcb->state == LISTEN (called for wrong pcb?)", \
+                                               pcb->state == LISTEN)
+#endif /* TCP_LISTEN_BACKLOG */
+
+void             tcp_recved  (struct tcp_pcb *pcb, u16_t len);
+err_t            tcp_bind    (struct tcp_pcb *pcb, ip_addr_t *ipaddr,
+                              u16_t port);
+err_t            tcp_connect (struct tcp_pcb *pcb, ip_addr_t *ipaddr,
+                              u16_t port, tcp_connected_fn connected);
+
+struct tcp_pcb * tcp_listen_with_backlog(struct tcp_pcb *pcb, u8_t backlog);
+#define          tcp_listen(pcb) tcp_listen_with_backlog(pcb, TCP_DEFAULT_LISTEN_BACKLOG)
+
+void             tcp_abort (struct tcp_pcb *pcb);
+err_t            tcp_close   (struct tcp_pcb *pcb);
+err_t            tcp_shutdown(struct tcp_pcb *pcb, int shut_rx, int shut_tx);
+
+/* Flags for "apiflags" parameter in tcp_write */
+#define TCP_WRITE_FLAG_COPY 0x01
+#define TCP_WRITE_FLAG_MORE 0x02
+
+err_t            tcp_write   (struct tcp_pcb *pcb, const void *dataptr, u16_t len,
+                              u8_t apiflags);
+
+void             tcp_setprio (struct tcp_pcb *pcb, u8_t prio);
+
+#define TCP_PRIO_MIN    1
+#define TCP_PRIO_NORMAL 64
+#define TCP_PRIO_MAX    127
+
+err_t            tcp_output  (struct tcp_pcb *pcb);
+
+
+const char* tcp_debug_state_str(enum tcp_state s);
+
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* LWIP_TCP */
+
+#endif /* __LWIP_TCP_H__ */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/include/lwip/tcp_impl.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,472 @@
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+#ifndef __LWIP_TCP_IMPL_H__
+#define __LWIP_TCP_IMPL_H__
+
+#include "lwip/opt.h"
+
+#if LWIP_TCP /* don't build if not configured for use in lwipopts.h */
+
+#include "lwip/tcp.h"
+#include "lwip/sys.h"
+#include "lwip/mem.h"
+#include "lwip/pbuf.h"
+#include "lwip/ip.h"
+#include "lwip/icmp.h"
+#include "lwip/err.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* Functions for interfacing with TCP: */
+
+/* Lower layer interface to TCP: */
+#define tcp_init() /* Compatibility define, no init needed. */
+void             tcp_tmr     (void);  /* Must be called every
+                                         TCP_TMR_INTERVAL
+                                         ms. (Typically 250 ms). */
+/* It is also possible to call these two functions at the right
+   intervals (instead of calling tcp_tmr()). */
+void             tcp_slowtmr (void);
+void             tcp_fasttmr (void);
+
+
+/* Only used by IP to pass a TCP segment to TCP: */
+void             tcp_input   (struct pbuf *p, struct netif *inp);
+/* Used within the TCP code only: */
+struct tcp_pcb * tcp_alloc   (u8_t prio);
+void             tcp_abandon (struct tcp_pcb *pcb, int reset);
+err_t            tcp_send_empty_ack(struct tcp_pcb *pcb);
+void             tcp_rexmit  (struct tcp_pcb *pcb);
+void             tcp_rexmit_rto  (struct tcp_pcb *pcb);
+void             tcp_rexmit_fast (struct tcp_pcb *pcb);
+u32_t            tcp_update_rcv_ann_wnd(struct tcp_pcb *pcb);
+
+/**
+ * This is the Nagle algorithm: try to combine user data to send as few TCP
+ * segments as possible. Only send if
+ * - no previously transmitted data on the connection remains unacknowledged or
+ * - the TF_NODELAY flag is set (nagle algorithm turned off for this pcb) or
+ * - the only unsent segment is at least pcb->mss bytes long (or there is more
+ *   than one unsent segment - with lwIP, this can happen although unsent->len < mss)
+ * - or if we are in fast-retransmit (TF_INFR)
+ */
+#define tcp_do_output_nagle(tpcb) ((((tpcb)->unacked == NULL) || \
+                            ((tpcb)->flags & (TF_NODELAY | TF_INFR)) || \
+                            (((tpcb)->unsent != NULL) && (((tpcb)->unsent->next != NULL) || \
+                              ((tpcb)->unsent->len >= (tpcb)->mss))) \
+                            ) ? 1 : 0)
+#define tcp_output_nagle(tpcb) (tcp_do_output_nagle(tpcb) ? tcp_output(tpcb) : ERR_OK)
+
+
+#define TCP_SEQ_LT(a,b)     ((s32_t)((a)-(b)) < 0)
+#define TCP_SEQ_LEQ(a,b)    ((s32_t)((a)-(b)) <= 0)
+#define TCP_SEQ_GT(a,b)     ((s32_t)((a)-(b)) > 0)
+#define TCP_SEQ_GEQ(a,b)    ((s32_t)((a)-(b)) >= 0)
+/* is b<=a<=c? */
+#if 0 /* see bug #10548 */
+#define TCP_SEQ_BETWEEN(a,b,c) ((c)-(b) >= (a)-(b))
+#endif
+#define TCP_SEQ_BETWEEN(a,b,c) (TCP_SEQ_GEQ(a,b) && TCP_SEQ_LEQ(a,c))
+#define TCP_FIN 0x01U
+#define TCP_SYN 0x02U
+#define TCP_RST 0x04U
+#define TCP_PSH 0x08U
+#define TCP_ACK 0x10U
+#define TCP_URG 0x20U
+#define TCP_ECE 0x40U
+#define TCP_CWR 0x80U
+
+#define TCP_FLAGS 0x3fU
+
+/* Length of the TCP header, excluding options. */
+#define TCP_HLEN 20
+
+#ifndef TCP_TMR_INTERVAL
+#define TCP_TMR_INTERVAL       250  /* The TCP timer interval in milliseconds. */
+#endif /* TCP_TMR_INTERVAL */
+
+#ifndef TCP_FAST_INTERVAL
+#define TCP_FAST_INTERVAL      TCP_TMR_INTERVAL /* the fine grained timeout in milliseconds */
+#endif /* TCP_FAST_INTERVAL */
+
+#ifndef TCP_SLOW_INTERVAL
+#define TCP_SLOW_INTERVAL      (2*TCP_TMR_INTERVAL)  /* the coarse grained timeout in milliseconds */
+#endif /* TCP_SLOW_INTERVAL */
+
+#define TCP_FIN_WAIT_TIMEOUT 20000 /* milliseconds */
+#define TCP_SYN_RCVD_TIMEOUT 20000 /* milliseconds */
+
+#define TCP_OOSEQ_TIMEOUT        6U /* x RTO */
+
+#ifndef TCP_MSL
+#define TCP_MSL 60000UL /* The maximum segment lifetime in milliseconds */
+#endif
+
+/* Keepalive values, compliant with RFC 1122. Don't change this unless you know what you're doing */
+#ifndef  TCP_KEEPIDLE_DEFAULT
+#define  TCP_KEEPIDLE_DEFAULT     7200000UL /* Default KEEPALIVE timer in milliseconds */
+#endif
+
+#ifndef  TCP_KEEPINTVL_DEFAULT
+#define  TCP_KEEPINTVL_DEFAULT    75000UL   /* Default Time between KEEPALIVE probes in milliseconds */
+#endif
+
+#ifndef  TCP_KEEPCNT_DEFAULT
+#define  TCP_KEEPCNT_DEFAULT      9U        /* Default Counter for KEEPALIVE probes */
+#endif
+
+#define  TCP_MAXIDLE              TCP_KEEPCNT_DEFAULT * TCP_KEEPINTVL_DEFAULT  /* Maximum KEEPALIVE probe time */
+
+/* Fields are (of course) in network byte order.
+ * Some fields are converted to host byte order in tcp_input().
+ */
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/bpstruct.h"
+#endif
+PACK_STRUCT_BEGIN
+struct tcp_hdr {
+  PACK_STRUCT_FIELD(u16_t src);
+  PACK_STRUCT_FIELD(u16_t dest);
+  PACK_STRUCT_FIELD(u32_t seqno);
+  PACK_STRUCT_FIELD(u32_t ackno);
+  PACK_STRUCT_FIELD(u16_t _hdrlen_rsvd_flags);
+  PACK_STRUCT_FIELD(u16_t wnd);
+  PACK_STRUCT_FIELD(u16_t chksum);
+  PACK_STRUCT_FIELD(u16_t urgp);
+} PACK_STRUCT_STRUCT;
+PACK_STRUCT_END
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/epstruct.h"
+#endif
+
+#define TCPH_OFFSET(phdr) (ntohs((phdr)->_hdrlen_rsvd_flags) >> 8)
+#define TCPH_HDRLEN(phdr) (ntohs((phdr)->_hdrlen_rsvd_flags) >> 12)
+#define TCPH_FLAGS(phdr)  (ntohs((phdr)->_hdrlen_rsvd_flags) & TCP_FLAGS)
+
+#define TCPH_OFFSET_SET(phdr, offset) (phdr)->_hdrlen_rsvd_flags = htons(((offset) << 8) | TCPH_FLAGS(phdr))
+#define TCPH_HDRLEN_SET(phdr, len) (phdr)->_hdrlen_rsvd_flags = htons(((len) << 12) | TCPH_FLAGS(phdr))
+#define TCPH_FLAGS_SET(phdr, flags) (phdr)->_hdrlen_rsvd_flags = (((phdr)->_hdrlen_rsvd_flags & PP_HTONS((u16_t)(~(u16_t)(TCP_FLAGS)))) | htons(flags))
+#define TCPH_HDRLEN_FLAGS_SET(phdr, len, flags) (phdr)->_hdrlen_rsvd_flags = htons(((len) << 12) | (flags))
+
+#define TCPH_SET_FLAG(phdr, flags ) (phdr)->_hdrlen_rsvd_flags = ((phdr)->_hdrlen_rsvd_flags | htons(flags))
+#define TCPH_UNSET_FLAG(phdr, flags) (phdr)->_hdrlen_rsvd_flags = htons(ntohs((phdr)->_hdrlen_rsvd_flags) | (TCPH_FLAGS(phdr) & ~(flags)) )
+
+#define TCP_TCPLEN(seg) ((seg)->len + ((TCPH_FLAGS((seg)->tcphdr) & (TCP_FIN | TCP_SYN)) != 0))
+
+/** Flags used on input processing, not on pcb->flags
+*/
+#define TF_RESET     (u8_t)0x08U   /* Connection was reset. */
+#define TF_CLOSED    (u8_t)0x10U   /* Connection was sucessfully closed. */
+#define TF_GOT_FIN   (u8_t)0x20U   /* Connection was closed by the remote end. */
+
+
+#if LWIP_EVENT_API
+
+#define TCP_EVENT_ACCEPT(pcb,err,ret)    ret = lwip_tcp_event((pcb)->callback_arg, (pcb),\
+                LWIP_EVENT_ACCEPT, NULL, 0, err)
+#define TCP_EVENT_SENT(pcb,space,ret) ret = lwip_tcp_event((pcb)->callback_arg, (pcb),\
+                   LWIP_EVENT_SENT, NULL, space, ERR_OK)
+#define TCP_EVENT_RECV(pcb,p,err,ret) ret = lwip_tcp_event((pcb)->callback_arg, (pcb),\
+                LWIP_EVENT_RECV, (p), 0, (err))
+#define TCP_EVENT_CLOSED(pcb,ret) ret = lwip_tcp_event((pcb)->callback_arg, (pcb),\
+                LWIP_EVENT_RECV, NULL, 0, ERR_OK)
+#define TCP_EVENT_CONNECTED(pcb,err,ret) ret = lwip_tcp_event((pcb)->callback_arg, (pcb),\
+                LWIP_EVENT_CONNECTED, NULL, 0, (err))
+#define TCP_EVENT_POLL(pcb,ret)       ret = lwip_tcp_event((pcb)->callback_arg, (pcb),\
+                LWIP_EVENT_POLL, NULL, 0, ERR_OK)
+#define TCP_EVENT_ERR(errf,arg,err)  lwip_tcp_event((arg), NULL, \
+                LWIP_EVENT_ERR, NULL, 0, (err))
+
+#else /* LWIP_EVENT_API */
+
+#define TCP_EVENT_ACCEPT(pcb,err,ret)                          \
+  do {                                                         \
+    if((pcb)->accept != NULL)                                  \
+      (ret) = (pcb)->accept((pcb)->callback_arg,(pcb),(err));  \
+    else (ret) = ERR_ARG;                                      \
+  } while (0)
+
+#define TCP_EVENT_SENT(pcb,space,ret)                          \
+  do {                                                         \
+    if((pcb)->sent != NULL)                                    \
+      (ret) = (pcb)->sent((pcb)->callback_arg,(pcb),(space));  \
+    else (ret) = ERR_OK;                                       \
+  } while (0)
+
+#define TCP_EVENT_RECV(pcb,p,err,ret)                          \
+  do {                                                         \
+    if((pcb)->recv != NULL) {                                  \
+      (ret) = (pcb)->recv((pcb)->callback_arg,(pcb),(p),(err));\
+    } else {                                                   \
+      (ret) = tcp_recv_null(NULL, (pcb), (p), (err));          \
+    }                                                          \
+  } while (0)
+
+#define TCP_EVENT_CLOSED(pcb,ret)                                \
+  do {                                                           \
+    if(((pcb)->recv != NULL)) {                                  \
+      (ret) = (pcb)->recv((pcb)->callback_arg,(pcb),NULL,ERR_OK);\
+    } else {                                                     \
+      (ret) = ERR_OK;                                            \
+    }                                                            \
+  } while (0)
+
+#define TCP_EVENT_CONNECTED(pcb,err,ret)                         \
+  do {                                                           \
+    if((pcb)->connected != NULL)                                 \
+      (ret) = (pcb)->connected((pcb)->callback_arg,(pcb),(err)); \
+    else (ret) = ERR_OK;                                         \
+  } while (0)
+
+#define TCP_EVENT_POLL(pcb,ret)                                \
+  do {                                                         \
+    if((pcb)->poll != NULL)                                    \
+      (ret) = (pcb)->poll((pcb)->callback_arg,(pcb));          \
+    else (ret) = ERR_OK;                                       \
+  } while (0)
+
+#define TCP_EVENT_ERR(errf,arg,err)                            \
+  do {                                                         \
+    if((errf) != NULL)                                         \
+      (errf)((arg),(err));                                     \
+  } while (0)
+
+#endif /* LWIP_EVENT_API */
+
+/** Enabled extra-check for TCP_OVERSIZE if LWIP_DEBUG is enabled */
+#if TCP_OVERSIZE && defined(LWIP_DEBUG)
+#define TCP_OVERSIZE_DBGCHECK 1
+#else
+#define TCP_OVERSIZE_DBGCHECK 0
+#endif
+
+/** Don't generate checksum on copy if CHECKSUM_GEN_TCP is disabled */
+#define TCP_CHECKSUM_ON_COPY  (LWIP_CHECKSUM_ON_COPY && CHECKSUM_GEN_TCP)
+
+/* This structure represents a TCP segment on the unsent, unacked and ooseq queues */
+struct tcp_seg {
+  struct tcp_seg *next;    /* used when putting segements on a queue */
+  struct pbuf *p;          /* buffer containing data + TCP header */
+  void *dataptr;           /* pointer to the TCP data in the pbuf */
+  u16_t len;               /* the TCP length of this segment */
+#if TCP_OVERSIZE_DBGCHECK
+  u16_t oversize_left;     /* Extra bytes available at the end of the last
+                              pbuf in unsent (used for asserting vs.
+                              tcp_pcb.unsent_oversized only) */
+#endif /* TCP_OVERSIZE_DBGCHECK */ 
+#if TCP_CHECKSUM_ON_COPY
+  u16_t chksum;
+  u8_t  chksum_swapped;
+#endif /* TCP_CHECKSUM_ON_COPY */
+  u8_t  flags;
+#define TF_SEG_OPTS_MSS         (u8_t)0x01U /* Include MSS option. */
+#define TF_SEG_OPTS_TS          (u8_t)0x02U /* Include timestamp option. */
+#define TF_SEG_DATA_CHECKSUMMED (u8_t)0x04U /* ALL data (not the header) is
+                                               checksummed into 'chksum' */
+  struct tcp_hdr *tcphdr;  /* the TCP header */
+};
+
+#define LWIP_TCP_OPT_LENGTH(flags)              \
+  (flags & TF_SEG_OPTS_MSS ? 4  : 0) +          \
+  (flags & TF_SEG_OPTS_TS  ? 12 : 0)
+
+/** This returns a TCP header option for MSS in an u32_t */
+#define TCP_BUILD_MSS_OPTION(x) (x) = PP_HTONL(((u32_t)2 << 24) |          \
+                                               ((u32_t)4 << 16) |          \
+                                               (((u32_t)TCP_MSS / 256) << 8) | \
+                                               (TCP_MSS & 255))
+
+/* Global variables: */
+extern struct tcp_pcb *tcp_input_pcb;
+extern u32_t tcp_ticks;
+
+/* The TCP PCB lists. */
+union tcp_listen_pcbs_t { /* List of all TCP PCBs in LISTEN state. */
+  struct tcp_pcb_listen *listen_pcbs; 
+  struct tcp_pcb *pcbs;
+};
+extern struct tcp_pcb *tcp_bound_pcbs;
+extern union tcp_listen_pcbs_t tcp_listen_pcbs;
+extern struct tcp_pcb *tcp_active_pcbs;  /* List of all TCP PCBs that are in a
+              state in which they accept or send
+              data. */
+extern struct tcp_pcb *tcp_tw_pcbs;      /* List of all TCP PCBs in TIME-WAIT. */
+
+extern struct tcp_pcb *tcp_tmp_pcb;      /* Only used for temporary storage. */
+
+/* Axioms about the above lists:   
+   1) Every TCP PCB that is not CLOSED is in one of the lists.
+   2) A PCB is only in one of the lists.
+   3) All PCBs in the tcp_listen_pcbs list is in LISTEN state.
+   4) All PCBs in the tcp_tw_pcbs list is in TIME-WAIT state.
+*/
+/* Define two macros, TCP_REG and TCP_RMV that registers a TCP PCB
+   with a PCB list or removes a PCB from a list, respectively. */
+#ifndef TCP_DEBUG_PCB_LISTS
+#define TCP_DEBUG_PCB_LISTS 0
+#endif
+#if TCP_DEBUG_PCB_LISTS
+#define TCP_REG(pcbs, npcb) do {\
+                            LWIP_DEBUGF(TCP_DEBUG, ("TCP_REG %p local port %d\n", (npcb), (npcb)->local_port)); \
+                            for(tcp_tmp_pcb = *(pcbs); \
+          tcp_tmp_pcb != NULL; \
+        tcp_tmp_pcb = tcp_tmp_pcb->next) { \
+                                LWIP_ASSERT("TCP_REG: already registered\n", tcp_tmp_pcb != (npcb)); \
+                            } \
+                            LWIP_ASSERT("TCP_REG: pcb->state != CLOSED", ((pcbs) == &tcp_bound_pcbs) || ((npcb)->state != CLOSED)); \
+                            (npcb)->next = *(pcbs); \
+                            LWIP_ASSERT("TCP_REG: npcb->next != npcb", (npcb)->next != (npcb)); \
+                            *(pcbs) = (npcb); \
+                            LWIP_ASSERT("TCP_RMV: tcp_pcbs sane", tcp_pcbs_sane()); \
+              tcp_timer_needed(); \
+                            } while(0)
+#define TCP_RMV(pcbs, npcb) do { \
+                            LWIP_ASSERT("TCP_RMV: pcbs != NULL", *(pcbs) != NULL); \
+                            LWIP_DEBUGF(TCP_DEBUG, ("TCP_RMV: removing %p from %p\n", (npcb), *(pcbs))); \
+                            if(*(pcbs) == (npcb)) { \
+                               *(pcbs) = (*pcbs)->next; \
+                            } else for(tcp_tmp_pcb = *(pcbs); tcp_tmp_pcb != NULL; tcp_tmp_pcb = tcp_tmp_pcb->next) { \
+                               if(tcp_tmp_pcb->next == (npcb)) { \
+                                  tcp_tmp_pcb->next = (npcb)->next; \
+                                  break; \
+                               } \
+                            } \
+                            (npcb)->next = NULL; \
+                            LWIP_ASSERT("TCP_RMV: tcp_pcbs sane", tcp_pcbs_sane()); \
+                            LWIP_DEBUGF(TCP_DEBUG, ("TCP_RMV: removed %p from %p\n", (npcb), *(pcbs))); \
+                            } while(0)
+
+#else /* LWIP_DEBUG */
+
+#define TCP_REG(pcbs, npcb)                        \
+  do {                                             \
+    (npcb)->next = *pcbs;                          \
+    *(pcbs) = (npcb);                              \
+    tcp_timer_needed();                            \
+  } while (0)
+
+#define TCP_RMV(pcbs, npcb)                        \
+  do {                                             \
+    if(*(pcbs) == (npcb)) {                        \
+      (*(pcbs)) = (*pcbs)->next;                   \
+    }                                              \
+    else {                                         \
+      for(tcp_tmp_pcb = *pcbs;                     \
+          tcp_tmp_pcb != NULL;                     \
+          tcp_tmp_pcb = tcp_tmp_pcb->next) {       \
+        if(tcp_tmp_pcb->next == (npcb)) {          \
+          tcp_tmp_pcb->next = (npcb)->next;        \
+          break;                                   \
+        }                                          \
+      }                                            \
+    }                                              \
+    (npcb)->next = NULL;                           \
+  } while(0)
+
+#endif /* LWIP_DEBUG */
+
+
+/* Internal functions: */
+struct tcp_pcb *tcp_pcb_copy(struct tcp_pcb *pcb);
+void tcp_pcb_purge(struct tcp_pcb *pcb);
+void tcp_pcb_remove(struct tcp_pcb **pcblist, struct tcp_pcb *pcb);
+
+void tcp_segs_free(struct tcp_seg *seg);
+void tcp_seg_free(struct tcp_seg *seg);
+struct tcp_seg *tcp_seg_copy(struct tcp_seg *seg);
+
+#define tcp_ack(pcb)                               \
+  do {                                             \
+    if((pcb)->flags & TF_ACK_DELAY) {              \
+      (pcb)->flags &= ~TF_ACK_DELAY;               \
+      (pcb)->flags |= TF_ACK_NOW;                  \
+    }                                              \
+    else {                                         \
+      (pcb)->flags |= TF_ACK_DELAY;                \
+    }                                              \
+  } while (0)
+
+#define tcp_ack_now(pcb)                           \
+  do {                                             \
+    (pcb)->flags |= TF_ACK_NOW;                    \
+  } while (0)
+
+err_t tcp_send_fin(struct tcp_pcb *pcb);
+err_t tcp_enqueue_flags(struct tcp_pcb *pcb, u8_t flags);
+
+void tcp_rexmit_seg(struct tcp_pcb *pcb, struct tcp_seg *seg);
+
+void tcp_rst(u32_t seqno, u32_t ackno,
+       ip_addr_t *local_ip, ip_addr_t *remote_ip,
+       u16_t local_port, u16_t remote_port);
+
+u32_t tcp_next_iss(void);
+
+void tcp_keepalive(struct tcp_pcb *pcb);
+void tcp_zero_window_probe(struct tcp_pcb *pcb);
+
+#if TCP_CALCULATE_EFF_SEND_MSS
+u16_t tcp_eff_send_mss(u16_t sendmss, ip_addr_t *addr);
+#endif /* TCP_CALCULATE_EFF_SEND_MSS */
+
+#if LWIP_CALLBACK_API
+err_t tcp_recv_null(void *arg, struct tcp_pcb *pcb, struct pbuf *p, err_t err);
+#endif /* LWIP_CALLBACK_API */
+
+#if TCP_DEBUG || TCP_INPUT_DEBUG || TCP_OUTPUT_DEBUG
+void tcp_debug_print(struct tcp_hdr *tcphdr);
+void tcp_debug_print_flags(u8_t flags);
+void tcp_debug_print_state(enum tcp_state s);
+void tcp_debug_print_pcbs(void);
+s16_t tcp_pcbs_sane(void);
+#else
+#  define tcp_debug_print(tcphdr)
+#  define tcp_debug_print_flags(flags)
+#  define tcp_debug_print_state(s)
+#  define tcp_debug_print_pcbs()
+#  define tcp_pcbs_sane() 1
+#endif /* TCP_DEBUG */
+
+/** External function (implemented in timers.c), called when TCP detects
+ * that a timer is needed (i.e. active- or time-wait-pcb found). */
+void tcp_timer_needed(void);
+
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* LWIP_TCP */
+
+#endif /* __LWIP_TCP_H__ */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/include/lwip/tcpip.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,159 @@
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+#ifndef __LWIP_TCPIP_H__
+#define __LWIP_TCPIP_H__
+
+#include "lwip/opt.h"
+
+#if !NO_SYS /* don't build if not configured for use in lwipopts.h */
+
+#include "lwip/api_msg.h"
+#include "lwip/netifapi.h"
+#include "lwip/pbuf.h"
+#include "lwip/api.h"
+#include "lwip/sys.h"
+#include "lwip/timers.h"
+#include "lwip/netif.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/** Define this to something that triggers a watchdog. This is called from
+ * tcpip_thread after processing a message. */
+#ifndef LWIP_TCPIP_THREAD_ALIVE
+#define LWIP_TCPIP_THREAD_ALIVE()
+#endif
+
+#if LWIP_TCPIP_CORE_LOCKING
+/** The global semaphore to lock the stack. */
+extern sys_mutex_t lock_tcpip_core;
+#define LOCK_TCPIP_CORE()     sys_mutex_lock(&lock_tcpip_core)
+#define UNLOCK_TCPIP_CORE()   sys_mutex_unlock(&lock_tcpip_core)
+#define TCPIP_APIMSG(m)       tcpip_apimsg_lock(m)
+#define TCPIP_APIMSG_ACK(m)
+#define TCPIP_NETIFAPI(m)     tcpip_netifapi_lock(m)
+#define TCPIP_NETIFAPI_ACK(m)
+#else /* LWIP_TCPIP_CORE_LOCKING */
+#define LOCK_TCPIP_CORE()
+#define UNLOCK_TCPIP_CORE()
+#define TCPIP_APIMSG(m)       tcpip_apimsg(m)
+#define TCPIP_APIMSG_ACK(m)   sys_sem_signal(&m->conn->op_completed)
+#define TCPIP_NETIFAPI(m)     tcpip_netifapi(m)
+#define TCPIP_NETIFAPI_ACK(m) sys_sem_signal(&m->sem)
+#endif /* LWIP_TCPIP_CORE_LOCKING */
+
+/** Function prototype for the init_done function passed to tcpip_init */
+typedef void (*tcpip_init_done_fn)(void *arg);
+/** Function prototype for functions passed to tcpip_callback() */
+typedef void (*tcpip_callback_fn)(void *ctx);
+
+void tcpip_init(tcpip_init_done_fn tcpip_init_done, void *arg);
+
+#if LWIP_NETCONN
+err_t tcpip_apimsg(struct api_msg *apimsg);
+#if LWIP_TCPIP_CORE_LOCKING
+err_t tcpip_apimsg_lock(struct api_msg *apimsg);
+#endif /* LWIP_TCPIP_CORE_LOCKING */
+#endif /* LWIP_NETCONN */
+
+err_t tcpip_input(struct pbuf *p, struct netif *inp);
+
+#if LWIP_NETIF_API
+err_t tcpip_netifapi(struct netifapi_msg *netifapimsg);
+#if LWIP_TCPIP_CORE_LOCKING
+err_t tcpip_netifapi_lock(struct netifapi_msg *netifapimsg);
+#endif /* LWIP_TCPIP_CORE_LOCKING */
+#endif /* LWIP_NETIF_API */
+
+err_t tcpip_callback_with_block(tcpip_callback_fn function, void *ctx, u8_t block);
+#define tcpip_callback(f, ctx)              tcpip_callback_with_block(f, ctx, 1)
+
+/* free pbufs or heap memory from another context without blocking */
+err_t pbuf_free_callback(struct pbuf *p);
+err_t mem_free_callback(void *m);
+
+#if LWIP_TCPIP_TIMEOUT
+err_t tcpip_timeout(u32_t msecs, sys_timeout_handler h, void *arg);
+err_t tcpip_untimeout(sys_timeout_handler h, void *arg);
+#endif /* LWIP_TCPIP_TIMEOUT */
+
+enum tcpip_msg_type {
+#if LWIP_NETCONN
+  TCPIP_MSG_API,
+#endif /* LWIP_NETCONN */
+  TCPIP_MSG_INPKT,
+#if LWIP_NETIF_API
+  TCPIP_MSG_NETIFAPI,
+#endif /* LWIP_NETIF_API */
+#if LWIP_TCPIP_TIMEOUT
+  TCPIP_MSG_TIMEOUT,
+  TCPIP_MSG_UNTIMEOUT,
+#endif /* LWIP_TCPIP_TIMEOUT */
+  TCPIP_MSG_CALLBACK
+};
+
+struct tcpip_msg {
+  enum tcpip_msg_type type;
+  sys_sem_t *sem;
+  union {
+#if LWIP_NETCONN
+    struct api_msg *apimsg;
+#endif /* LWIP_NETCONN */
+#if LWIP_NETIF_API
+    struct netifapi_msg *netifapimsg;
+#endif /* LWIP_NETIF_API */
+    struct {
+      struct pbuf *p;
+      struct netif *netif;
+    } inp;
+    struct {
+      tcpip_callback_fn function;
+      void *ctx;
+    } cb;
+#if LWIP_TCPIP_TIMEOUT
+    struct {
+      u32_t msecs;
+      sys_timeout_handler h;
+      void *arg;
+    } tmo;
+#endif /* LWIP_TCPIP_TIMEOUT */
+  } msg;
+};
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* !NO_SYS */
+
+#endif /* __LWIP_TCPIP_H__ */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/include/lwip/timers.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,98 @@
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *         Simon Goldschmidt
+ *
+ */
+#ifndef __LWIP_TIMERS_H__
+#define __LWIP_TIMERS_H__
+
+#include "lwip/opt.h"
+
+/* Timers are not supported when NO_SYS==1 and NO_SYS_NO_TIMERS==1 */
+#define LWIP_TIMERS (!NO_SYS || (NO_SYS && !NO_SYS_NO_TIMERS))
+
+#if LWIP_TIMERS
+
+#include "lwip/err.h"
+#include "lwip/sys.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#ifndef LWIP_DEBUG_TIMERNAMES
+#ifdef LWIP_DEBUG
+#define LWIP_DEBUG_TIMERNAMES SYS_DEBUG
+#else /* LWIP_DEBUG */
+#define LWIP_DEBUG_TIMERNAMES 0
+#endif /* LWIP_DEBUG*/
+#endif
+
+/** Function prototype for a timeout callback function. Register such a function
+ * using sys_timeout().
+ *
+ * @param arg Additional argument to pass to the function - set up by sys_timeout()
+ */
+typedef void (* sys_timeout_handler)(void *arg);
+
+struct sys_timeo {
+  struct sys_timeo *next;
+  u32_t time;
+  sys_timeout_handler h;
+  void *arg;
+#if LWIP_DEBUG_TIMERNAMES
+  const char* handler_name;
+#endif /* LWIP_DEBUG_TIMERNAMES */
+};
+
+void sys_timeouts_init(void);
+
+#if LWIP_DEBUG_TIMERNAMES
+void sys_timeout_debug(u32_t msecs, sys_timeout_handler handler, void *arg, const char* handler_name);
+#define sys_timeout(msecs, handler, arg) sys_timeout_debug(msecs, handler, arg, #handler)
+#else /* LWIP_DEBUG_TIMERNAMES */
+void sys_timeout(u32_t msecs, sys_timeout_handler handler, void *arg);
+#endif /* LWIP_DEBUG_TIMERNAMES */
+
+void sys_untimeout(sys_timeout_handler handler, void *arg);
+#if NO_SYS
+void sys_check_timeouts(void);
+void sys_restart_timeouts(void);
+#else /* NO_SYS */
+void sys_timeouts_mbox_fetch(sys_mbox_t *mbox, void **msg);
+#endif /* NO_SYS */
+
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* LWIP_TIMERS */
+#endif /* __LWIP_TIMERS_H__ */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/include/lwip/udp.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,171 @@
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+#ifndef __LWIP_UDP_H__
+#define __LWIP_UDP_H__
+
+#include "lwip/opt.h"
+
+#if LWIP_UDP /* don't build if not configured for use in lwipopts.h */
+
+#include "lwip/pbuf.h"
+#include "lwip/netif.h"
+#include "lwip/ip_addr.h"
+#include "lwip/ip.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#define UDP_HLEN 8
+
+/* Fields are (of course) in network byte order. */
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/bpstruct.h"
+#endif
+PACK_STRUCT_BEGIN
+struct udp_hdr {
+  PACK_STRUCT_FIELD(u16_t src);
+  PACK_STRUCT_FIELD(u16_t dest);  /* src/dest UDP ports */
+  PACK_STRUCT_FIELD(u16_t len);
+  PACK_STRUCT_FIELD(u16_t chksum);
+} PACK_STRUCT_STRUCT;
+PACK_STRUCT_END
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/epstruct.h"
+#endif
+
+#define UDP_FLAGS_NOCHKSUM       0x01U
+#define UDP_FLAGS_UDPLITE        0x02U
+#define UDP_FLAGS_CONNECTED      0x04U
+#define UDP_FLAGS_MULTICAST_LOOP 0x08U
+
+struct udp_pcb;
+
+/** Function prototype for udp pcb receive callback functions
+ * addr and port are in same byte order as in the pcb
+ * The callback is responsible for freeing the pbuf
+ * if it's not used any more.
+ *
+ * ATTENTION: Be aware that 'addr' points into the pbuf 'p' so freeing this pbuf
+ *            makes 'addr' invalid, too.
+ *
+ * @param arg user supplied argument (udp_pcb.recv_arg)
+ * @param pcb the udp_pcb which received data
+ * @param p the packet buffer that was received
+ * @param addr the remote IP address from which the packet was received
+ * @param port the remote port from which the packet was received
+ */
+typedef void (*udp_recv_fn)(void *arg, struct udp_pcb *pcb, struct pbuf *p,
+    ip_addr_t *addr, u16_t port);
+
+
+struct udp_pcb {
+/* Common members of all PCB types */
+  IP_PCB;
+
+/* Protocol specific PCB members */
+
+  struct udp_pcb *next;
+
+  u8_t flags;
+  /** ports are in host byte order */
+  u16_t local_port, remote_port;
+
+#if LWIP_IGMP
+  /** outgoing network interface for multicast packets */
+  ip_addr_t multicast_ip;
+#endif /* LWIP_IGMP */
+
+#if LWIP_UDPLITE
+  /** used for UDP_LITE only */
+  u16_t chksum_len_rx, chksum_len_tx;
+#endif /* LWIP_UDPLITE */
+
+  /** receive callback function */
+  udp_recv_fn recv;
+  /** user-supplied argument for the recv callback */
+  void *recv_arg;  
+};
+/* udp_pcbs export for exernal reference (e.g. SNMP agent) */
+extern struct udp_pcb *udp_pcbs;
+
+/* The following functions is the application layer interface to the
+   UDP code. */
+struct udp_pcb * udp_new        (void);
+void             udp_remove     (struct udp_pcb *pcb);
+err_t            udp_bind       (struct udp_pcb *pcb, ip_addr_t *ipaddr,
+                                 u16_t port);
+err_t            udp_connect    (struct udp_pcb *pcb, ip_addr_t *ipaddr,
+                                 u16_t port);
+void             udp_disconnect (struct udp_pcb *pcb);
+void             udp_recv       (struct udp_pcb *pcb, udp_recv_fn recv,
+                                 void *recv_arg);
+err_t            udp_sendto_if  (struct udp_pcb *pcb, struct pbuf *p,
+                                 ip_addr_t *dst_ip, u16_t dst_port,
+                                 struct netif *netif);
+err_t            udp_sendto     (struct udp_pcb *pcb, struct pbuf *p,
+                                 ip_addr_t *dst_ip, u16_t dst_port);
+err_t            udp_send       (struct udp_pcb *pcb, struct pbuf *p);
+
+#if LWIP_CHECKSUM_ON_COPY
+err_t            udp_sendto_if_chksum(struct udp_pcb *pcb, struct pbuf *p,
+                                 ip_addr_t *dst_ip, u16_t dst_port,
+                                 struct netif *netif, u8_t have_chksum,
+                                 u16_t chksum);
+err_t            udp_sendto_chksum(struct udp_pcb *pcb, struct pbuf *p,
+                                 ip_addr_t *dst_ip, u16_t dst_port,
+                                 u8_t have_chksum, u16_t chksum);
+err_t            udp_send_chksum(struct udp_pcb *pcb, struct pbuf *p,
+                                 u8_t have_chksum, u16_t chksum);
+#endif /* LWIP_CHECKSUM_ON_COPY */
+
+#define          udp_flags(pcb) ((pcb)->flags)
+#define          udp_setflags(pcb, f)  ((pcb)->flags = (f))
+
+/* The following functions are the lower layer interface to UDP. */
+void             udp_input      (struct pbuf *p, struct netif *inp);
+
+#define udp_init() /* Compatibility define, not init needed. */
+
+#if UDP_DEBUG
+void udp_debug_print(struct udp_hdr *udphdr);
+#else
+#define udp_debug_print(udphdr)
+#endif
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* LWIP_UDP */
+
+#endif /* __LWIP_UDP_H__ */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/include/netif/etharp.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,221 @@
+/*
+ * Copyright (c) 2001-2003 Swedish Institute of Computer Science.
+ * Copyright (c) 2003-2004 Leon Woestenberg <leon.woestenberg@axon.tv>
+ * Copyright (c) 2003-2004 Axon Digital Design B.V., The Netherlands.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+
+#ifndef __NETIF_ETHARP_H__
+#define __NETIF_ETHARP_H__
+
+#include "lwip/opt.h"
+
+#if LWIP_ARP || LWIP_ETHERNET /* don't build if not configured for use in lwipopts.h */
+
+#include "lwip/pbuf.h"
+#include "lwip/ip_addr.h"
+#include "lwip/netif.h"
+#include "lwip/ip.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#ifndef ETHARP_HWADDR_LEN
+#define ETHARP_HWADDR_LEN     6
+#endif
+
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/bpstruct.h"
+#endif
+PACK_STRUCT_BEGIN
+struct eth_addr {
+  PACK_STRUCT_FIELD(u8_t addr[ETHARP_HWADDR_LEN]);
+} PACK_STRUCT_STRUCT;
+PACK_STRUCT_END
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/epstruct.h"
+#endif
+
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/bpstruct.h"
+#endif
+PACK_STRUCT_BEGIN
+/* Ethernet header */
+struct eth_hdr {
+#if ETH_PAD_SIZE
+  PACK_STRUCT_FIELD(u8_t padding[ETH_PAD_SIZE]);
+#endif
+  PACK_STRUCT_FIELD(struct eth_addr dest);
+  PACK_STRUCT_FIELD(struct eth_addr src);
+  PACK_STRUCT_FIELD(u16_t type);
+} PACK_STRUCT_STRUCT;
+PACK_STRUCT_END
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/epstruct.h"
+#endif
+
+#define SIZEOF_ETH_HDR (14 + ETH_PAD_SIZE)
+
+#if ETHARP_SUPPORT_VLAN
+
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/bpstruct.h"
+#endif
+PACK_STRUCT_BEGIN
+/* VLAN header inserted between ethernet header and payload
+ * if 'type' in ethernet header is ETHTYPE_VLAN.
+ * See IEEE802.Q */
+struct eth_vlan_hdr {
+  PACK_STRUCT_FIELD(u16_t tpid);
+  PACK_STRUCT_FIELD(u16_t prio_vid);
+} PACK_STRUCT_STRUCT;
+PACK_STRUCT_END
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/epstruct.h"
+#endif
+
+#define SIZEOF_VLAN_HDR 4
+#define VLAN_ID(vlan_hdr) (htons((vlan_hdr)->prio_vid) & 0xFFF)
+
+#endif /* ETHARP_SUPPORT_VLAN */
+
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/bpstruct.h"
+#endif
+PACK_STRUCT_BEGIN
+/* the ARP message, see RFC 826 ("Packet format") */
+struct etharp_hdr {
+  PACK_STRUCT_FIELD(u16_t hwtype);
+  PACK_STRUCT_FIELD(u16_t proto);
+  PACK_STRUCT_FIELD(u8_t  hwlen);
+  PACK_STRUCT_FIELD(u8_t  protolen);
+  PACK_STRUCT_FIELD(u16_t opcode);
+  PACK_STRUCT_FIELD(struct eth_addr shwaddr);
+  PACK_STRUCT_FIELD(struct ip_addr2 sipaddr);
+  PACK_STRUCT_FIELD(struct eth_addr dhwaddr);
+  PACK_STRUCT_FIELD(struct ip_addr2 dipaddr);
+} PACK_STRUCT_STRUCT;
+PACK_STRUCT_END
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/epstruct.h"
+#endif
+
+#define SIZEOF_ETHARP_HDR 28
+#define SIZEOF_ETHARP_PACKET (SIZEOF_ETH_HDR + SIZEOF_ETHARP_HDR)
+
+/* 5 seconds period */
+#define ARP_TMR_INTERVAL 5000
+
+#define ETHTYPE_ARP       0x0806
+#define ETHTYPE_IP        0x0800
+#define ETHTYPE_VLAN      0x8100
+#define ETHTYPE_PPPOEDISC 0x8863  /* PPP Over Ethernet Discovery Stage */
+#define ETHTYPE_PPPOE     0x8864  /* PPP Over Ethernet Session Stage */
+
+/* MEMCPY-like macro to copy to/from struct eth_addr's that are local variables
+ * or known to be 32-bit aligned within the protocol header. */
+#ifndef ETHADDR32_COPY
+#define ETHADDR32_COPY(src, dst)  SMEMCPY(src, dst, ETHARP_HWADDR_LEN)
+#endif
+
+/* MEMCPY-like macro to copy to/from struct eth_addr's that are no local
+ * variables and known to be 16-bit aligned within the protocol header. */
+#ifndef ETHADDR16_COPY
+#define ETHADDR16_COPY(src, dst)  SMEMCPY(src, dst, ETHARP_HWADDR_LEN)
+#endif
+
+#if LWIP_ARP /* don't build if not configured for use in lwipopts.h */
+
+/* ARP message types (opcodes) */
+#define ARP_REQUEST 1
+#define ARP_REPLY   2
+
+/* Define this to 1 and define LWIP_ARP_FILTER_NETIF_FN(pbuf, netif, type)
+ * to a filter function that returns the correct netif when using multiple
+ * netifs on one hardware interface where the netif's low-level receive
+ * routine cannot decide for the correct netif (e.g. when mapping multiple
+ * IP addresses to one hardware interface).
+ */
+#ifndef LWIP_ARP_FILTER_NETIF
+#define LWIP_ARP_FILTER_NETIF 0
+#endif
+
+#if ARP_QUEUEING
+/* struct for queueing outgoing packets for unknown address
+  * defined here to be accessed by memp.h
+  */
+struct etharp_q_entry {
+  struct etharp_q_entry *next;
+  struct pbuf *p;
+};
+#endif /* ARP_QUEUEING */
+
+#define etharp_init() /* Compatibility define, not init needed. */
+void etharp_tmr(void);
+s8_t etharp_find_addr(struct netif *netif, ip_addr_t *ipaddr,
+         struct eth_addr **eth_ret, ip_addr_t **ip_ret);
+err_t etharp_output(struct netif *netif, struct pbuf *q, ip_addr_t *ipaddr);
+err_t etharp_query(struct netif *netif, ip_addr_t *ipaddr, struct pbuf *q);
+err_t etharp_request(struct netif *netif, ip_addr_t *ipaddr);
+/* For Ethernet network interfaces, we might want to send "gratuitous ARP";
+ *  this is an ARP packet sent by a node in order to spontaneously cause other
+ *  nodes to update an entry in their ARP cache.
+ *  From RFC 3220 "IP Mobility Support for IPv4" section 4.6. */
+#define etharp_gratuitous(netif) etharp_request((netif), &(netif)->ip_addr)
+
+#if ETHARP_SUPPORT_STATIC_ENTRIES
+err_t etharp_add_static_entry(ip_addr_t *ipaddr, struct eth_addr *ethaddr);
+err_t etharp_remove_static_entry(ip_addr_t *ipaddr);
+#endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
+
+#if LWIP_AUTOIP
+err_t etharp_raw(struct netif *netif, const struct eth_addr *ethsrc_addr,
+                 const struct eth_addr *ethdst_addr,
+                 const struct eth_addr *hwsrc_addr, const ip_addr_t *ipsrc_addr,
+                 const struct eth_addr *hwdst_addr, const ip_addr_t *ipdst_addr,
+                 const u16_t opcode);
+#endif /* LWIP_AUTOIP */
+
+#endif /* LWIP_ARP */
+
+err_t ethernet_input(struct pbuf *p, struct netif *netif);
+
+#define eth_addr_cmp(addr1, addr2) (memcmp((addr1)->addr, (addr2)->addr, ETHARP_HWADDR_LEN) == 0)
+
+extern const struct eth_addr ethbroadcast, ethzero;
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* LWIP_ARP || LWIP_ETHERNET */
+
+#endif /* __NETIF_ARP_H__ */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/include/netif/ppp_oe.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,190 @@
+/*****************************************************************************
+* ppp_oe.h - PPP Over Ethernet implementation for lwIP.
+*
+* Copyright (c) 2006 by Marc Boucher, Services Informatiques (MBSI) inc.
+*
+* The authors hereby grant permission to use, copy, modify, distribute,
+* and license this software and its documentation for any purpose, provided
+* that existing copyright notices are retained in all copies and that this
+* notice and the following disclaimer are included verbatim in any 
+* distributions. No written agreement, license, or royalty fee is required
+* for any of the authorized uses.
+*
+* THIS SOFTWARE IS PROVIDED BY THE CONTRIBUTORS *AS IS* AND ANY EXPRESS OR
+* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 
+* IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*
+******************************************************************************
+* REVISION HISTORY
+*
+* 06-01-01 Marc Boucher <marc@mbsi.ca>
+*   Ported to lwIP.
+*****************************************************************************/
+
+
+
+/* based on NetBSD: if_pppoe.c,v 1.64 2006/01/31 23:50:15 martin Exp */
+
+/*-
+ * Copyright (c) 2002 The NetBSD Foundation, Inc.
+ * All rights reserved.
+ *
+ * This code is derived from software contributed to The NetBSD Foundation
+ * by Martin Husemann <martin@NetBSD.org>.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *        This product includes software developed by the NetBSD
+ *        Foundation, Inc. and its contributors.
+ * 4. Neither the name of The NetBSD Foundation nor the names of its
+ *    contributors may be used to endorse or promote products derived
+ *    from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+ * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
+ * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+#ifndef PPP_OE_H
+#define PPP_OE_H
+
+#include "lwip/opt.h"
+
+#if PPPOE_SUPPORT > 0
+
+#include "netif/etharp.h"
+
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/bpstruct.h"
+#endif
+PACK_STRUCT_BEGIN
+struct pppoehdr {
+  PACK_STRUCT_FIELD(u8_t vertype);
+  PACK_STRUCT_FIELD(u8_t code);
+  PACK_STRUCT_FIELD(u16_t session);
+  PACK_STRUCT_FIELD(u16_t plen);
+} PACK_STRUCT_STRUCT;
+PACK_STRUCT_END
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/epstruct.h"
+#endif
+
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/bpstruct.h"
+#endif
+PACK_STRUCT_BEGIN
+struct pppoetag {
+  PACK_STRUCT_FIELD(u16_t tag);
+  PACK_STRUCT_FIELD(u16_t len);
+} PACK_STRUCT_STRUCT;
+PACK_STRUCT_END
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/epstruct.h"
+#endif
+
+
+#define PPPOE_STATE_INITIAL   0
+#define PPPOE_STATE_PADI_SENT 1
+#define PPPOE_STATE_PADR_SENT 2
+#define PPPOE_STATE_SESSION   3
+#define PPPOE_STATE_CLOSING   4
+/* passive */
+#define PPPOE_STATE_PADO_SENT 1
+
+#define PPPOE_HEADERLEN       sizeof(struct pppoehdr)
+#define PPPOE_VERTYPE         0x11    /* VER=1, TYPE = 1 */
+
+#define PPPOE_TAG_EOL         0x0000  /* end of list */
+#define PPPOE_TAG_SNAME       0x0101  /* service name */
+#define PPPOE_TAG_ACNAME      0x0102  /* access concentrator name */
+#define PPPOE_TAG_HUNIQUE     0x0103  /* host unique */
+#define PPPOE_TAG_ACCOOKIE    0x0104  /* AC cookie */
+#define PPPOE_TAG_VENDOR      0x0105  /* vendor specific */
+#define PPPOE_TAG_RELAYSID    0x0110  /* relay session id */
+#define PPPOE_TAG_SNAME_ERR   0x0201  /* service name error */
+#define PPPOE_TAG_ACSYS_ERR   0x0202  /* AC system error */
+#define PPPOE_TAG_GENERIC_ERR 0x0203  /* gerneric error */
+
+#define PPPOE_CODE_PADI       0x09    /* Active Discovery Initiation */
+#define PPPOE_CODE_PADO       0x07    /* Active Discovery Offer */
+#define PPPOE_CODE_PADR       0x19    /* Active Discovery Request */
+#define PPPOE_CODE_PADS       0x65    /* Active Discovery Session confirmation */
+#define PPPOE_CODE_PADT       0xA7    /* Active Discovery Terminate */
+
+#ifndef ETHERMTU
+#define ETHERMTU 1500
+#endif
+
+/* two byte PPP protocol discriminator, then IP data */
+#define PPPOE_MAXMTU          (ETHERMTU-PPPOE_HEADERLEN-2)
+
+#ifndef PPPOE_MAX_AC_COOKIE_LEN
+#define PPPOE_MAX_AC_COOKIE_LEN   64
+#endif
+
+struct pppoe_softc {
+  struct pppoe_softc *next;
+  struct netif *sc_ethif;      /* ethernet interface we are using */
+  int sc_pd;                   /* ppp unit number */
+  void (*sc_linkStatusCB)(int pd, int up);
+
+  int sc_state;                /* discovery phase or session connected */
+  struct eth_addr sc_dest;     /* hardware address of concentrator */
+  u16_t sc_session;            /* PPPoE session id */
+
+#ifdef PPPOE_TODO
+  char *sc_service_name;       /* if != NULL: requested name of service */
+  char *sc_concentrator_name;  /* if != NULL: requested concentrator id */
+#endif /* PPPOE_TODO */
+  u8_t sc_ac_cookie[PPPOE_MAX_AC_COOKIE_LEN]; /* content of AC cookie we must echo back */
+  size_t sc_ac_cookie_len;     /* length of cookie data */
+#ifdef PPPOE_SERVER
+  u8_t *sc_hunique;            /* content of host unique we must echo back */
+  size_t sc_hunique_len;       /* length of host unique */
+#endif
+  int sc_padi_retried;         /* number of PADI retries already done */
+  int sc_padr_retried;         /* number of PADR retries already done */
+};
+
+
+#define pppoe_init() /* compatibility define, no initialization needed */
+
+err_t pppoe_create(struct netif *ethif, int pd, void (*linkStatusCB)(int pd, int up), struct pppoe_softc **scptr);
+err_t pppoe_destroy(struct netif *ifp);
+
+int pppoe_connect(struct pppoe_softc *sc);
+void pppoe_disconnect(struct pppoe_softc *sc);
+
+void pppoe_disc_input(struct netif *netif, struct pbuf *p);
+void pppoe_data_input(struct netif *netif, struct pbuf *p);
+
+err_t pppoe_xmit(struct pppoe_softc *sc, struct pbuf *pb);
+
+/** used in ppp.c */
+#define PPPOE_HDRLEN (sizeof(struct eth_hdr) + PPPOE_HEADERLEN)
+
+#endif /* PPPOE_SUPPORT */
+
+#endif /* PPP_OE_H */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/include/netif/slipif.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,51 @@
+/*
+ * Copyright (c) 2001, Swedish Institute of Computer Science.
+ * All rights reserved. 
+ *
+ * Redistribution and use in source and binary forms, with or without 
+ * modification, are permitted provided that the following conditions 
+ * are met: 
+ * 1. Redistributions of source code must retain the above copyright 
+ *    notice, this list of conditions and the following disclaimer. 
+ * 2. Redistributions in binary form must reproduce the above copyright 
+ *    notice, this list of conditions and the following disclaimer in the 
+ *    documentation and/or other materials provided with the distribution. 
+ * 3. Neither the name of the Institute nor the names of its contributors 
+ *    may be used to endorse or promote products derived from this software 
+ *    without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND 
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE 
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 
+ * SUCH DAMAGE. 
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+#ifndef __NETIF_SLIPIF_H__
+#define __NETIF_SLIPIF_H__
+
+#include "lwip/netif.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+err_t slipif_init(struct netif * netif);
+void slipif_poll(struct netif *netif);
+
+#ifdef __cplusplus
+}
+#endif
+ 
+#endif 
+
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/lwipopts.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,463 @@
+/*
+ * Copyright (c) 2001-2003 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+#ifndef __LWIPOPTS_H__
+#define __LWIPOPTS_H__
+
+#include "netCfg.h"
+#if NET_LWIP_STACK
+
+//#include "arch/sys_arch.h"
+
+/* <sys/time.h> is included in cc.h! */
+#define LWIP_TIMEVAL_PRIVATE 0
+
+//#define __LWIP_DEBUG
+#include "dbg/dbg.h"
+
+#ifdef __LWIP_DEBUG
+
+#define LWIP_DEBUG 1
+
+#define LWIP_DBG_MIN_LEVEL 0
+//#define LWIP_COMPAT_SOCKETS 1
+#define TAPIF_DEBUG LWIP_DBG_OFF
+#define TUNIF_DEBUG LWIP_DBG_OFF
+#define UNIXIF_DEBUG LWIP_DBG_OFF
+#define DELIF_DEBUG LWIP_DBG_OFF
+#define SIO_FIFO_DEBUG LWIP_DBG_OFF
+#define TCPDUMP_DEBUG LWIP_DBG_OFF
+
+#define PPP_DEBUG        LWIP_DBG_OFF
+#define MEM_DEBUG        LWIP_DBG_OFF
+#define MEMP_DEBUG       LWIP_DBG_OFF
+#define PBUF_DEBUG       LWIP_DBG_OFF
+#define API_LIB_DEBUG    LWIP_DBG_OFF
+#define API_MSG_DEBUG    LWIP_DBG_OFF
+#define TCPIP_DEBUG      LWIP_DBG_OFF
+#define NETIF_DEBUG      LWIP_DBG_OFF
+#define SOCKETS_DEBUG    LWIP_DBG_OFF
+#define DEMO_DEBUG       LWIP_DBG_OFF
+#define IP_DEBUG         LWIP_DBG_OFF
+#define IP_REASS_DEBUG   LWIP_DBG_OFF
+#define RAW_DEBUG        LWIP_DBG_OFF
+#define ICMP_DEBUG       LWIP_DBG_OFF
+#define IGMP_DEBUG       LWIP_DBG_OFF
+#define UDP_DEBUG        LWIP_DBG_OFF
+#define TCP_DEBUG        LWIP_DBG_OFF
+#define TCP_INPUT_DEBUG  LWIP_DBG_OFF
+#define TCP_OUTPUT_DEBUG LWIP_DBG_OFF
+#define TCP_RTO_DEBUG    LWIP_DBG_OFF
+#define TCP_CWND_DEBUG   LWIP_DBG_OFF
+#define TCP_WND_DEBUG    LWIP_DBG_OFF
+#define TCP_FR_DEBUG     LWIP_DBG_OFF
+#define TCP_QLEN_DEBUG   LWIP_DBG_OFF
+#define TCP_RST_DEBUG    LWIP_DBG_OFF
+#define ETHARP_DEBUG     LWIP_DBG_OFF
+#define DNS_DEBUG        LWIP_DBG_OFF
+
+#endif
+
+/*
+extern unsigned char debug_flags;
+#define LWIP_DBG_TYPES_ON debug_flags
+*/
+#define NO_SYS                     1
+#define LWIP_SOCKET                (NO_SYS==0)
+#define LWIP_NETCONN               (NO_SYS==0)
+
+
+#define IP_FRAG_USES_STATIC_BUF         0
+
+
+
+/* ---------- Memory options ---------- */
+/* MEM_ALIGNMENT: should be set to the alignment of the CPU for which
+   lwIP is compiled. 4 byte alignment -> define MEM_ALIGNMENT to 4, 2
+   byte alignment -> define MEM_ALIGNMENT to 2. */
+/* MSVC port: intel processors don't need 4-byte alignment,
+   but are faster that way! */
+#define MEM_ALIGNMENT           4
+
+/* MEM_SIZE: the size of the heap memory. If the application will send
+a lot of data that needs to be copied, this should be set high. */
+//#define MEM_SIZE               10240 
+
+#if TARGET_LPC1768
+
+
+#define MEM_SIZE               3000 //2000
+
+///
+
+#define MEM_POSITION __attribute((section("AHBSRAM1"),aligned))
+
+/* MEMP_NUM_PBUF: the number of memp struct pbufs. If the application
+   sends a lot of data out of ROM (or other static memory), this
+   should be set high. */
+#define MEMP_NUM_PBUF           16
+/* MEMP_NUM_RAW_PCB: the number of UDP protocol control blocks. One
+   per active RAW "connection". */
+//#define MEMP_NUM_RAW_PCB        3
+/* MEMP_NUM_UDP_PCB: the number of UDP protocol control blocks. One
+   per active UDP "connection". */
+#define MEMP_NUM_UDP_PCB        4
+/* MEMP_NUM_TCP_PCB: the number of simulatenously active TCP
+   connections. */
+#define MEMP_NUM_TCP_PCB        3
+/* MEMP_NUM_TCP_PCB_LISTEN: the number of listening TCP
+   connections. */
+#define MEMP_NUM_TCP_PCB_LISTEN 2//4
+/* MEMP_NUM_TCP_SEG: the number of simultaneously queued TCP
+   segments. */
+#define MEMP_NUM_TCP_SEG        16
+/* MEMP_NUM_SYS_TIMEOUT: the number of simulateously active
+   timeouts. */
+#define MEMP_NUM_SYS_TIMEOUT    12
+
+/* The following four are used only with the sequential API and can be
+   set to 0 if the application only will use the raw API. */
+/* MEMP_NUM_NETBUF: the number of struct netbufs. */
+#define MEMP_NUM_NETBUF         0
+/* MEMP_NUM_NETCONN: the number of struct netconns. */
+#define MEMP_NUM_NETCONN        0
+/* MEMP_NUM_TCPIP_MSG_*: the number of struct tcpip_msg, which is used
+   for sequential API communication and incoming packets. Used in
+   src/api/tcpip.c. */
+#define MEMP_NUM_TCPIP_MSG_API   0
+#define MEMP_NUM_TCPIP_MSG_INPKT 0
+
+/* ---------- Pbuf options ---------- */
+/* PBUF_POOL_SIZE: the number of buffers in the pbuf pool. */
+#define PBUF_POOL_SIZE          8//16//100
+
+/* PBUF_POOL_BUFSIZE: the size of each pbuf in the pbuf pool. */
+//#define PBUF_POOL_BUFSIZE       128
+
+/* PBUF_LINK_HLEN: the number of bytes that should be allocated for a
+   link level header. */
+//#define PBUF_LINK_HLEN          16 
+
+/** SYS_LIGHTWEIGHT_PROT
+ * define SYS_LIGHTWEIGHT_PROT in lwipopts.h if you want inter-task protection
+ * for certain critical regions during buffer allocation, deallocation and memory
+ * allocation and deallocation.
+ */
+#define SYS_LIGHTWEIGHT_PROT           0 //No sys here
+
+/* ---------- TCP options ---------- */
+#define LWIP_TCP                1
+//#define TCP_TTL                 255
+
+/* Controls if TCP should queue segments that arrive out of
+   order. Define to 0 if your device is low on memory. */
+#define TCP_QUEUE_OOSEQ         1
+
+/* TCP Maximum segment size. */
+//#define TCP_MSS                 1024
+#define TCP_MSS                   536//1024//536//0x276
+
+/* TCP sender buffer space (bytes). */
+#define TCP_SND_BUF             (3 * TCP_MSS) //2048
+
+/* TCP sender buffer space (pbufs). This must be at least = 2 *
+   TCP_SND_BUF/TCP_MSS for things to work. */
+#define TCP_SND_QUEUELEN        (4 * (TCP_SND_BUF)/(TCP_MSS))
+
+/* TCP writable space (bytes). This must be less than or equal
+   to TCP_SND_BUF. It is the amount of space which must be
+   available in the tcp snd_buf for select to return writable */
+#define TCP_SNDLOWAT        ((TCP_SND_BUF)/2)
+
+/**
+ * TCP_WND: The size of a TCP window.  This must be at least 
+ * (2 * TCP_MSS) for things to work well
+ */
+/* TCP receive window. */
+#define TCP_WND        (4 * TCP_MSS)         //8096
+
+/* Maximum number of retransmissions of data segments. */
+//#define TCP_MAXRTX              12
+
+/* Maximum number of retransmissions of SYN segments. */
+//#define TCP_SYNMAXRTX           4
+
+#elif TARGET_LPC2368
+
+#define MEM_POSITION __attribute((section("AHBSRAM1")))
+
+/* MEMP_NUM_PBUF: the number of memp struct pbufs. If the application
+   sends a lot of data out of ROM (or other static memory), this
+   should be set high. */
+#define MEMP_NUM_PBUF           8
+/* MEMP_NUM_RAW_PCB: the number of UDP protocol control blocks. One
+   per active RAW "connection". */
+//#define MEMP_NUM_RAW_PCB        3
+/* MEMP_NUM_UDP_PCB: the number of UDP protocol control blocks. One
+   per active UDP "connection". */
+#define MEMP_NUM_UDP_PCB        2
+/* MEMP_NUM_TCP_PCB: the number of simulatenously active TCP
+   connections. */
+#define MEMP_NUM_TCP_PCB        2
+/* MEMP_NUM_TCP_PCB_LISTEN: the number of listening TCP
+   connections. */
+#define MEMP_NUM_TCP_PCB_LISTEN 2//4
+/* MEMP_NUM_TCP_SEG: the number of simultaneously queued TCP
+   segments. */
+#define MEMP_NUM_TCP_SEG        8
+/* MEMP_NUM_SYS_TIMEOUT: the number of simulateously active
+   timeouts. */
+#define MEMP_NUM_SYS_TIMEOUT    12
+
+/* The following four are used only with the sequential API and can be
+   set to 0 if the application only will use the raw API. */
+/* MEMP_NUM_NETBUF: the number of struct netbufs. */
+#define MEMP_NUM_NETBUF         0
+/* MEMP_NUM_NETCONN: the number of struct netconns. */
+#define MEMP_NUM_NETCONN        0
+/* MEMP_NUM_TCPIP_MSG_*: the number of struct tcpip_msg, which is used
+   for sequential API communication and incoming packets. Used in
+   src/api/tcpip.c. */
+#define MEMP_NUM_TCPIP_MSG_API   0
+#define MEMP_NUM_TCPIP_MSG_INPKT 0
+
+/* ---------- Pbuf options ---------- */
+/* PBUF_POOL_SIZE: the number of buffers in the pbuf pool. */
+#define PBUF_POOL_SIZE          8//16//100
+
+/* PBUF_POOL_BUFSIZE: the size of each pbuf in the pbuf pool. */
+//#define PBUF_POOL_BUFSIZE       128
+
+/* PBUF_LINK_HLEN: the number of bytes that should be allocated for a
+   link level header. */
+//#define PBUF_LINK_HLEN          16 
+
+/** SYS_LIGHTWEIGHT_PROT
+ * define SYS_LIGHTWEIGHT_PROT in lwipopts.h if you want inter-task protection
+ * for certain critical regions during buffer allocation, deallocation and memory
+ * allocation and deallocation.
+ */
+#define SYS_LIGHTWEIGHT_PROT           0 //No sys here
+
+/* ---------- TCP options ---------- */
+#define LWIP_TCP                1
+#define TCP_TTL                 255
+
+/* Controls if TCP should queue segments that arrive out of
+   order. Define to 0 if your device is low on memory. */
+#define TCP_QUEUE_OOSEQ         0
+
+/* TCP Maximum segment size. */
+//#define TCP_MSS                 1024
+#define TCP_MSS                   536//0x276//536//0x276
+
+/* TCP sender buffer space (bytes). */
+#define TCP_SND_BUF             (3 * TCP_MSS)
+
+/* TCP sender buffer space (pbufs). This must be at least = 2 *
+   TCP_SND_BUF/TCP_MSS for things to work. */
+#define TCP_SND_QUEUELEN        (2 * TCP_SND_BUF/TCP_MSS)//(4 * TCP_SND_BUF/TCP_MSS)
+
+/* TCP writable space (bytes). This must be less than or equal
+   to TCP_SND_BUF. It is the amount of space which must be
+   available in the tcp snd_buf for select to return writable */
+#define TCP_SNDLOWAT        (TCP_SND_BUF/2)
+
+/* TCP receive window. */
+#define TCP_WND        (3 * TCP_MSS)         //8096
+
+/* Maximum number of retransmissions of data segments. */
+//#define TCP_MAXRTX              12
+
+/* Maximum number of retransmissions of SYN segments. */
+//#define TCP_SYNMAXRTX           4
+
+#endif
+
+/* ---------- ARP options ---------- */
+#define LWIP_ARP                (NET_ETH | NET_ZG2100)
+#define ARP_TABLE_SIZE          4//10
+#define ARP_QUEUEING            0
+#define ETHARP_TRUST_IP_MAC     1
+
+/* ---------- IP options ---------- */
+/* Define IP_FORWARD to 1 if you wish to have the ability to forward
+   IP packets across network interfaces. If you are going to run lwIP
+   on a device with only one network interface, define this to 0. */
+#define IP_FORWARD              0
+
+
+/* IP reassembly and segmentation.These are orthogonal even
+ * if they both deal with IP fragments */
+ /*
+#define IP_REASSEMBLY     1
+#define IP_REASS_MAX_PBUFS      10
+#define MEMP_NUM_REASSDATA      10
+#define IP_FRAG           1
+*/
+/* ---------- ICMP options ---------- */
+#define ICMP_TTL                255
+
+/* ---------- IGMP options ---------- */
+#define LWIP_IGMP               (NET_ETH | NET_ZG2100)
+
+/* ---------- DHCP options ---------- */
+/* Define LWIP_DHCP to 1 if you want DHCP configuration of
+   interfaces. */
+#define LWIP_DHCP               (NET_ETH | NET_ZG2100)
+#define LWIP_NETIF_HOSTNAME     1
+
+/* 1 if you want to do an ARP check on the offered address
+   (recommended if using DHCP). */
+#define DHCP_DOES_ARP_CHECK     (LWIP_DHCP)
+
+/* ---------- AUTOIP options ------- */
+#define LWIP_AUTOIP             0
+
+/* ---------- SNMP options ---------- */
+/** @todo SNMP is experimental for now
+    @note UDP must be available for SNMP transport */
+#ifndef LWIP_SNMP
+#define LWIP_SNMP               0
+#endif
+
+
+#ifndef SNMP_PRIVATE_MIB
+#define SNMP_PRIVATE_MIB        0
+#endif
+
+
+/* ---------- UDP options ---------- */
+#define LWIP_UDP                1
+#define UDP_TTL                 255
+
+/* ---------- DNS options ---------- */
+#define LWIP_DNS                1
+
+/* ---------- RAW options ---------- */
+#define LWIP_RAW                0
+#define RAW_TTL                 255
+
+/* ---------- Statistics options ---------- */
+/* individual STATS options can be turned off by defining them to 0 
+ * (e.g #define TCP_STATS 0). All of them are turned off if LWIP_STATS
+ * is 0
+ * */
+
+#define LWIP_STATS    0
+
+/* ---------- PPP options ---------- */
+
+#define PPP_SUPPORT      NET_PPP      /* Set > 0 for PPP */
+
+#if PPP_SUPPORT > 0
+
+#define NUM_PPP 1           /* Max PPP sessions. */
+
+
+/* Select modules to enable.  Ideally these would be set in the makefile but
+ * we're limited by the command line length so you need to modify the settings
+ * in this file.
+ */
+#define PAP_SUPPORT      1      /* Set > 0 for PAP. */
+#define CHAP_SUPPORT     1      /* Set > 0 for CHAP. */
+#define MSCHAP_SUPPORT   0      /* Set > 0 for MSCHAP (NOT FUNCTIONAL!) */
+#define CBCP_SUPPORT     0      /* Set > 0 for CBCP (NOT FUNCTIONAL!) */
+#define CCP_SUPPORT      0      /* Set > 0 for CCP (NOT FUNCTIONAL!) */
+#define VJ_SUPPORT       1      /* Set > 0 for VJ header compression. */
+#define MD5_SUPPORT      1      /* Set > 0 for MD5 (see also CHAP) */
+
+
+/*
+ * Timeouts.
+ */
+#define FSM_DEFTIMEOUT        6    /* Timeout time in seconds */
+#define FSM_DEFMAXTERMREQS    2    /* Maximum Terminate-Request transmissions */
+#define FSM_DEFMAXCONFREQS    10    /* Maximum Configure-Request transmissions */
+#define FSM_DEFMAXNAKLOOPS    5    /* Maximum number of nak loops */
+
+#define UPAP_DEFTIMEOUT        6    /* Timeout (seconds) for retransmitting req */
+#define UPAP_DEFREQTIME        30    /* Time to wait for auth-req from peer */
+
+#define CHAP_DEFTIMEOUT        6    /* Timeout time in seconds */
+#define CHAP_DEFTRANSMITS    10    /* max # times to send challenge */
+
+
+/* Interval in seconds between keepalive echo requests, 0 to disable. */
+#if 1
+#define LCP_ECHOINTERVAL 0
+#else
+
+#define LCP_ECHOINTERVAL 10
+#endif
+
+
+/* Number of unanswered echo requests before failure. */
+#define LCP_MAXECHOFAILS 3
+
+/* Max Xmit idle time (in jiffies) before resend flag char. */
+#define PPP_MAXIDLEFLAG 0//Send it every time//100
+
+/*
+ * Packet sizes
+ *
+ * Note - lcp shouldn't be allowed to negotiate stuff outside these
+ *    limits.  See lcp.h in the pppd directory.
+ * (XXX - these constants should simply be shared by lcp.c instead
+ *    of living in lcp.h)
+ */
+#define PPP_MTU     1500     /* Default MTU (size of Info field) */
+#if 0
+#define PPP_MAXMTU  65535 - (PPP_HDRLEN + PPP_FCSLEN)
+#else
+
+#define PPP_MAXMTU  1500 /* Largest MTU we allow */
+#endif
+
+#define PPP_MINMTU  64
+#define PPP_MRU     1500     /* default MRU = max length of info field */
+#define PPP_MAXMRU  1500     /* Largest MRU we allow */
+#define PPP_DEFMRU    296        /* Try for this */
+#define PPP_MINMRU    128        /* No MRUs below this */
+
+
+#define MAXNAMELEN      64     /* max length of hostname or name for auth */
+#define MAXSECRETLEN    64     /* max length of password or secret */
+
+#endif /* PPP_SUPPORT > 0 */
+
+//C++ Compat
+#define try vTry
+
+#endif
+
+
+#endif /* __LWIPOPTS_H__ */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/netif/etharp.c	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,1285 @@
+/**
+ * @file
+ * Address Resolution Protocol module for IP over Ethernet
+ *
+ * Functionally, ARP is divided into two parts. The first maps an IP address
+ * to a physical address when sending a packet, and the second part answers
+ * requests from other machines for our physical address.
+ *
+ * This implementation complies with RFC 826 (Ethernet ARP). It supports
+ * Gratuitious ARP from RFC3220 (IP Mobility Support for IPv4) section 4.6
+ * if an interface calls etharp_gratuitous(our_netif) upon address change.
+ */
+
+/*
+ * Copyright (c) 2001-2003 Swedish Institute of Computer Science.
+ * Copyright (c) 2003-2004 Leon Woestenberg <leon.woestenberg@axon.tv>
+ * Copyright (c) 2003-2004 Axon Digital Design B.V., The Netherlands.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ *
+ */
+ 
+#include "lwip/opt.h"
+
+#if LWIP_ARP || LWIP_ETHERNET
+
+#include "lwip/ip_addr.h"
+#include "lwip/def.h"
+#include "lwip/ip.h"
+#include "lwip/stats.h"
+#include "lwip/snmp.h"
+#include "lwip/dhcp.h"
+#include "lwip/autoip.h"
+#include "netif/etharp.h"
+
+#if PPPOE_SUPPORT
+#include "netif/ppp_oe.h"
+#endif /* PPPOE_SUPPORT */
+
+#include <string.h>
+
+const struct eth_addr ethbroadcast = {{0xff,0xff,0xff,0xff,0xff,0xff}};
+const struct eth_addr ethzero = {{0,0,0,0,0,0}};
+
+#if LWIP_ARP /* don't build if not configured for use in lwipopts.h */
+
+/** the time an ARP entry stays valid after its last update,
+ *  for ARP_TMR_INTERVAL = 5000, this is
+ *  (240 * 5) seconds = 20 minutes.
+ */
+#define ARP_MAXAGE 240
+/** the time an ARP entry stays pending after first request,
+ *  for ARP_TMR_INTERVAL = 5000, this is
+ *  (2 * 5) seconds = 10 seconds.
+ * 
+ *  @internal Keep this number at least 2, otherwise it might
+ *  run out instantly if the timeout occurs directly after a request.
+ */
+#define ARP_MAXPENDING 2
+
+#define HWTYPE_ETHERNET 1
+
+enum etharp_state {
+  ETHARP_STATE_EMPTY = 0,
+  ETHARP_STATE_PENDING,
+  ETHARP_STATE_STABLE
+};
+
+struct etharp_entry {
+#if ARP_QUEUEING
+  /** Pointer to queue of pending outgoing packets on this ARP entry. */
+  struct etharp_q_entry *q;
+#endif /* ARP_QUEUEING */
+  ip_addr_t ipaddr;
+  struct eth_addr ethaddr;
+#if LWIP_SNMP
+  struct netif *netif;
+#endif /* LWIP_SNMP */
+  u8_t state;
+  u8_t ctime;
+#if ETHARP_SUPPORT_STATIC_ENTRIES
+  u8_t static_entry;
+#endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
+};
+
+static struct etharp_entry arp_table[ARP_TABLE_SIZE];
+
+#if !LWIP_NETIF_HWADDRHINT
+static u8_t etharp_cached_entry;
+#endif /* !LWIP_NETIF_HWADDRHINT */
+
+/** Try hard to create a new entry - we want the IP address to appear in
+    the cache (even if this means removing an active entry or so). */
+#define ETHARP_FLAG_TRY_HARD     1
+#define ETHARP_FLAG_FIND_ONLY    2
+#define ETHARP_FLAG_STATIC_ENTRY 4
+
+#if LWIP_NETIF_HWADDRHINT
+#define ETHARP_SET_HINT(netif, hint)  if (((netif) != NULL) && ((netif)->addr_hint != NULL))  \
+                                      *((netif)->addr_hint) = (hint);
+#else /* LWIP_NETIF_HWADDRHINT */
+#define ETHARP_SET_HINT(netif, hint)  (etharp_cached_entry = (hint))
+#endif /* LWIP_NETIF_HWADDRHINT */
+
+static err_t update_arp_entry(struct netif *netif, ip_addr_t *ipaddr, struct eth_addr *ethaddr, u8_t flags);
+
+
+/* Some checks, instead of etharp_init(): */
+#if (LWIP_ARP && (ARP_TABLE_SIZE > 0x7f))
+  #error "ARP_TABLE_SIZE must fit in an s8_t, you have to reduce it in your lwipopts.h"
+#endif
+
+
+#if ARP_QUEUEING
+/**
+ * Free a complete queue of etharp entries
+ *
+ * @param q a qeueue of etharp_q_entry's to free
+ */
+static void
+free_etharp_q(struct etharp_q_entry *q)
+{
+  struct etharp_q_entry *r;
+  LWIP_ASSERT("q != NULL", q != NULL);
+  LWIP_ASSERT("q->p != NULL", q->p != NULL);
+  while (q) {
+    r = q;
+    q = q->next;
+    LWIP_ASSERT("r->p != NULL", (r->p != NULL));
+    pbuf_free(r->p);
+    memp_free(MEMP_ARP_QUEUE, r);
+  }
+}
+#endif /* ARP_QUEUEING */
+
+/** Clean up ARP table entries */
+static void
+free_entry(int i)
+{
+  /* remove from SNMP ARP index tree */
+  snmp_delete_arpidx_tree(arp_table[i].netif, &arp_table[i].ipaddr);
+#if ARP_QUEUEING
+  /* and empty packet queue */
+  if (arp_table[i].q != NULL) {
+    /* remove all queued packets */
+    LWIP_DEBUGF(ETHARP_DEBUG, ("etharp_timer: freeing entry %"U16_F", packet queue %p.\n", (u16_t)i, (void *)(arp_table[i].q)));
+    free_etharp_q(arp_table[i].q);
+    arp_table[i].q = NULL;
+  }
+#endif /* ARP_QUEUEING */
+  /* recycle entry for re-use */      
+  arp_table[i].state = ETHARP_STATE_EMPTY;
+#if ETHARP_SUPPORT_STATIC_ENTRIES
+  arp_table[i].static_entry = 0;
+#endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
+#ifdef LWIP_DEBUG
+  /* for debugging, clean out the complete entry */
+  arp_table[i].ctime = 0;
+#if LWIP_SNMP
+  arp_table[i].netif = NULL;
+#endif /* LWIP_SNMP */
+  ip_addr_set_zero(&arp_table[i].ipaddr);
+  arp_table[i].ethaddr = ethzero;
+#endif /* LWIP_DEBUG */
+}
+
+/**
+ * Clears expired entries in the ARP table.
+ *
+ * This function should be called every ETHARP_TMR_INTERVAL milliseconds (5 seconds),
+ * in order to expire entries in the ARP table.
+ */
+void
+etharp_tmr(void)
+{
+  u8_t i;
+
+  LWIP_DEBUGF(ETHARP_DEBUG, ("etharp_timer\n"));
+  /* remove expired entries from the ARP table */
+  for (i = 0; i < ARP_TABLE_SIZE; ++i) {
+    u8_t state = arp_table[i].state;
+    if (state != ETHARP_STATE_EMPTY
+#if ETHARP_SUPPORT_STATIC_ENTRIES
+      && (arp_table[i].static_entry == 0)
+#endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
+      ) {
+      arp_table[i].ctime++;
+      if ((arp_table[i].ctime >= ARP_MAXAGE) ||
+          ((arp_table[i].state == ETHARP_STATE_PENDING)  &&
+           (arp_table[i].ctime >= ARP_MAXPENDING))) {
+        /* pending or stable entry has become old! */
+        LWIP_DEBUGF(ETHARP_DEBUG, ("etharp_timer: expired %s entry %"U16_F".\n",
+             arp_table[i].state == ETHARP_STATE_STABLE ? "stable" : "pending", (u16_t)i));
+        /* clean up entries that have just been expired */
+        free_entry(i);
+      }
+#if ARP_QUEUEING
+      /* still pending entry? (not expired) */
+      if (arp_table[i].state == ETHARP_STATE_PENDING) {
+        /* resend an ARP query here? */
+      }
+#endif /* ARP_QUEUEING */
+    }
+  }
+}
+
+/**
+ * Search the ARP table for a matching or new entry.
+ * 
+ * If an IP address is given, return a pending or stable ARP entry that matches
+ * the address. If no match is found, create a new entry with this address set,
+ * but in state ETHARP_EMPTY. The caller must check and possibly change the
+ * state of the returned entry.
+ * 
+ * If ipaddr is NULL, return a initialized new entry in state ETHARP_EMPTY.
+ * 
+ * In all cases, attempt to create new entries from an empty entry. If no
+ * empty entries are available and ETHARP_FLAG_TRY_HARD flag is set, recycle
+ * old entries. Heuristic choose the least important entry for recycling.
+ *
+ * @param ipaddr IP address to find in ARP cache, or to add if not found.
+ * @param flags @see definition of ETHARP_FLAG_*
+ * @param netif netif related to this address (used for NETIF_HWADDRHINT)
+ *  
+ * @return The ARP entry index that matched or is created, ERR_MEM if no
+ * entry is found or could be recycled.
+ */
+static s8_t
+find_entry(ip_addr_t *ipaddr, u8_t flags)
+{
+  s8_t old_pending = ARP_TABLE_SIZE, old_stable = ARP_TABLE_SIZE;
+  s8_t empty = ARP_TABLE_SIZE;
+  u8_t i = 0, age_pending = 0, age_stable = 0;
+#if ARP_QUEUEING
+  /* oldest entry with packets on queue */
+  s8_t old_queue = ARP_TABLE_SIZE;
+  /* its age */
+  u8_t age_queue = 0;
+#endif /* ARP_QUEUEING */
+
+  /**
+   * a) do a search through the cache, remember candidates
+   * b) select candidate entry
+   * c) create new entry
+   */
+
+  /* a) in a single search sweep, do all of this
+   * 1) remember the first empty entry (if any)
+   * 2) remember the oldest stable entry (if any)
+   * 3) remember the oldest pending entry without queued packets (if any)
+   * 4) remember the oldest pending entry with queued packets (if any)
+   * 5) search for a matching IP entry, either pending or stable
+   *    until 5 matches, or all entries are searched for.
+   */
+
+  for (i = 0; i < ARP_TABLE_SIZE; ++i) {
+    u8_t state = arp_table[i].state;
+    /* no empty entry found yet and now we do find one? */
+    if ((empty == ARP_TABLE_SIZE) && (state == ETHARP_STATE_EMPTY)) {
+      LWIP_DEBUGF(ETHARP_DEBUG, ("find_entry: found empty entry %"U16_F"\n", (u16_t)i));
+      /* remember first empty entry */
+      empty = i;
+    } else if (state != ETHARP_STATE_EMPTY) {
+      LWIP_ASSERT("state == ETHARP_STATE_PENDING || state == ETHARP_STATE_STABLE",
+        state == ETHARP_STATE_PENDING || state == ETHARP_STATE_STABLE);
+      /* if given, does IP address match IP address in ARP entry? */
+      if (ipaddr && ip_addr_cmp(ipaddr, &arp_table[i].ipaddr)) {
+        LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("find_entry: found matching entry %"U16_F"\n", (u16_t)i));
+        /* found exact IP address match, simply bail out */
+        return i;
+      }
+      /* pending entry? */
+      if (state == ETHARP_STATE_PENDING) {
+        /* pending with queued packets? */
+#if ARP_QUEUEING
+        if (arp_table[i].q != NULL) {
+          if (arp_table[i].ctime >= age_queue) {
+            old_queue = i;
+            age_queue = arp_table[i].ctime;
+          }
+        } else
+#endif /* ARP_QUEUEING */
+        /* pending without queued packets? */
+        {
+          if (arp_table[i].ctime >= age_pending) {
+            old_pending = i;
+            age_pending = arp_table[i].ctime;
+          }
+        }
+      /* stable entry? */
+      } else if (state == ETHARP_STATE_STABLE) {
+#if ETHARP_SUPPORT_STATIC_ENTRIES
+        /* don't record old_stable for static entries since they never expire */
+        if (arp_table[i].static_entry == 0)
+#endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
+        {
+          /* remember entry with oldest stable entry in oldest, its age in maxtime */
+          if (arp_table[i].ctime >= age_stable) {
+            old_stable = i;
+            age_stable = arp_table[i].ctime;
+          }
+        }
+      }
+    }
+  }
+  /* { we have no match } => try to create a new entry */
+   
+  /* don't create new entry, only search? */
+  if (((flags & ETHARP_FLAG_FIND_ONLY) != 0) ||
+      /* or no empty entry found and not allowed to recycle? */
+      ((empty == ARP_TABLE_SIZE) && ((flags & ETHARP_FLAG_TRY_HARD) == 0))) {
+    LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("find_entry: no empty entry found and not allowed to recycle\n"));
+    return (s8_t)ERR_MEM;
+  }
+  
+  /* b) choose the least destructive entry to recycle:
+   * 1) empty entry
+   * 2) oldest stable entry
+   * 3) oldest pending entry without queued packets
+   * 4) oldest pending entry with queued packets
+   * 
+   * { ETHARP_FLAG_TRY_HARD is set at this point }
+   */ 
+
+  /* 1) empty entry available? */
+  if (empty < ARP_TABLE_SIZE) {
+    i = empty;
+    LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("find_entry: selecting empty entry %"U16_F"\n", (u16_t)i));
+  } else {
+    /* 2) found recyclable stable entry? */
+    if (old_stable < ARP_TABLE_SIZE) {
+      /* recycle oldest stable*/
+      i = old_stable;
+      LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("find_entry: selecting oldest stable entry %"U16_F"\n", (u16_t)i));
+#if ARP_QUEUEING
+      /* no queued packets should exist on stable entries */
+      LWIP_ASSERT("arp_table[i].q == NULL", arp_table[i].q == NULL);
+#endif /* ARP_QUEUEING */
+    /* 3) found recyclable pending entry without queued packets? */
+    } else if (old_pending < ARP_TABLE_SIZE) {
+      /* recycle oldest pending */
+      i = old_pending;
+      LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("find_entry: selecting oldest pending entry %"U16_F" (without queue)\n", (u16_t)i));
+#if ARP_QUEUEING
+    /* 4) found recyclable pending entry with queued packets? */
+    } else if (old_queue < ARP_TABLE_SIZE) {
+      /* recycle oldest pending (queued packets are free in free_entry) */
+      i = old_queue;
+      LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("find_entry: selecting oldest pending entry %"U16_F", freeing packet queue %p\n", (u16_t)i, (void *)(arp_table[i].q)));
+#endif /* ARP_QUEUEING */
+      /* no empty or recyclable entries found */
+    } else {
+      LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("find_entry: no empty or recyclable entries found\n"));
+      return (s8_t)ERR_MEM;
+    }
+
+    /* { empty or recyclable entry found } */
+    LWIP_ASSERT("i < ARP_TABLE_SIZE", i < ARP_TABLE_SIZE);
+    free_entry(i);
+  }
+
+  LWIP_ASSERT("i < ARP_TABLE_SIZE", i < ARP_TABLE_SIZE);
+  LWIP_ASSERT("arp_table[i].state == ETHARP_STATE_EMPTY",
+    arp_table[i].state == ETHARP_STATE_EMPTY);
+
+  /* IP address given? */
+  if (ipaddr != NULL) {
+    /* set IP address */
+    ip_addr_copy(arp_table[i].ipaddr, *ipaddr);
+  }
+  arp_table[i].ctime = 0;
+#if ETHARP_SUPPORT_STATIC_ENTRIES
+  arp_table[i].static_entry = 0;
+#endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
+  return (err_t)i;
+}
+
+/**
+ * Send an IP packet on the network using netif->linkoutput
+ * The ethernet header is filled in before sending.
+ *
+ * @params netif the lwIP network interface on which to send the packet
+ * @params p the packet to send, p->payload pointing to the (uninitialized) ethernet header
+ * @params src the source MAC address to be copied into the ethernet header
+ * @params dst the destination MAC address to be copied into the ethernet header
+ * @return ERR_OK if the packet was sent, any other err_t on failure
+ */
+static err_t
+etharp_send_ip(struct netif *netif, struct pbuf *p, struct eth_addr *src, struct eth_addr *dst)
+{
+  struct eth_hdr *ethhdr = (struct eth_hdr *)p->payload;
+
+  LWIP_ASSERT("netif->hwaddr_len must be the same as ETHARP_HWADDR_LEN for etharp!",
+              (netif->hwaddr_len == ETHARP_HWADDR_LEN));
+  ETHADDR32_COPY(&ethhdr->dest, dst);
+  ETHADDR16_COPY(&ethhdr->src, src);
+  ethhdr->type = PP_HTONS(ETHTYPE_IP);
+  LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("etharp_send_ip: sending packet %p\n", (void *)p));
+  /* send the packet */
+  return netif->linkoutput(netif, p);
+}
+
+/**
+ * Update (or insert) a IP/MAC address pair in the ARP cache.
+ *
+ * If a pending entry is resolved, any queued packets will be sent
+ * at this point.
+ * 
+ * @param netif netif related to this entry (used for NETIF_ADDRHINT)
+ * @param ipaddr IP address of the inserted ARP entry.
+ * @param ethaddr Ethernet address of the inserted ARP entry.
+ * @param flags @see definition of ETHARP_FLAG_*
+ *
+ * @return
+ * - ERR_OK Succesfully updated ARP cache.
+ * - ERR_MEM If we could not add a new ARP entry when ETHARP_FLAG_TRY_HARD was set.
+ * - ERR_ARG Non-unicast address given, those will not appear in ARP cache.
+ *
+ * @see pbuf_free()
+ */
+static err_t
+update_arp_entry(struct netif *netif, ip_addr_t *ipaddr, struct eth_addr *ethaddr, u8_t flags)
+{
+  s8_t i;
+  LWIP_ASSERT("netif->hwaddr_len == ETHARP_HWADDR_LEN", netif->hwaddr_len == ETHARP_HWADDR_LEN);
+  LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("update_arp_entry: %"U16_F".%"U16_F".%"U16_F".%"U16_F" - %02"X16_F":%02"X16_F":%02"X16_F":%02"X16_F":%02"X16_F":%02"X16_F"\n",
+    ip4_addr1_16(ipaddr), ip4_addr2_16(ipaddr), ip4_addr3_16(ipaddr), ip4_addr4_16(ipaddr),
+    ethaddr->addr[0], ethaddr->addr[1], ethaddr->addr[2],
+    ethaddr->addr[3], ethaddr->addr[4], ethaddr->addr[5]));
+  /* non-unicast address? */
+  if (ip_addr_isany(ipaddr) ||
+      ip_addr_isbroadcast(ipaddr, netif) ||
+      ip_addr_ismulticast(ipaddr)) {
+    LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("update_arp_entry: will not add non-unicast IP address to ARP cache\n"));
+    return ERR_ARG;
+  }
+  /* find or create ARP entry */
+  i = find_entry(ipaddr, flags);
+  /* bail out if no entry could be found */
+  if (i < 0) {
+    return (err_t)i;
+  }
+
+#if ETHARP_SUPPORT_STATIC_ENTRIES
+  if (flags & ETHARP_FLAG_STATIC_ENTRY) {
+    /* record static type */
+    arp_table[i].static_entry = 1;
+  }
+#endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
+
+  /* mark it stable */
+  arp_table[i].state = ETHARP_STATE_STABLE;
+
+#if LWIP_SNMP
+  /* record network interface */
+  arp_table[i].netif = netif;
+#endif /* LWIP_SNMP */
+  /* insert in SNMP ARP index tree */
+  snmp_insert_arpidx_tree(netif, &arp_table[i].ipaddr);
+
+  LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("update_arp_entry: updating stable entry %"S16_F"\n", (s16_t)i));
+  /* update address */
+  ETHADDR32_COPY(&arp_table[i].ethaddr, ethaddr);
+  /* reset time stamp */
+  arp_table[i].ctime = 0;
+#if ARP_QUEUEING
+  /* this is where we will send out queued packets! */
+  while (arp_table[i].q != NULL) {
+    struct pbuf *p;
+    /* remember remainder of queue */
+    struct etharp_q_entry *q = arp_table[i].q;
+    /* pop first item off the queue */
+    arp_table[i].q = q->next;
+    /* get the packet pointer */
+    p = q->p;
+    /* now queue entry can be freed */
+    memp_free(MEMP_ARP_QUEUE, q);
+    /* send the queued IP packet */
+    etharp_send_ip(netif, p, (struct eth_addr*)(netif->hwaddr), ethaddr);
+    /* free the queued IP packet */
+    pbuf_free(p);
+  }
+#endif /* ARP_QUEUEING */
+  return ERR_OK;
+}
+
+#if ETHARP_SUPPORT_STATIC_ENTRIES
+/** Add a new static entry to the ARP table. If an entry exists for the
+ * specified IP address, this entry is overwritten.
+ * If packets are queued for the specified IP address, they are sent out.
+ *
+ * @param ipaddr IP address for the new static entry
+ * @param ethaddr ethernet address for the new static entry
+ * @return @see return values of etharp_add_static_entry
+ */
+err_t
+etharp_add_static_entry(ip_addr_t *ipaddr, struct eth_addr *ethaddr)
+{
+  struct netif *netif;
+  LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("etharp_add_static_entry: %"U16_F".%"U16_F".%"U16_F".%"U16_F" - %02"X16_F":%02"X16_F":%02"X16_F":%02"X16_F":%02"X16_F":%02"X16_F"\n",
+    ip4_addr1_16(ipaddr), ip4_addr2_16(ipaddr), ip4_addr3_16(ipaddr), ip4_addr4_16(ipaddr),
+    ethaddr->addr[0], ethaddr->addr[1], ethaddr->addr[2],
+    ethaddr->addr[3], ethaddr->addr[4], ethaddr->addr[5]));
+
+  netif = ip_route(ipaddr);
+  if (netif == NULL) {
+    return ERR_RTE;
+  }
+
+  return update_arp_entry(netif, ipaddr, ethaddr, ETHARP_FLAG_TRY_HARD | ETHARP_FLAG_STATIC_ENTRY);
+}
+
+/** Remove a static entry from the ARP table previously added with a call to
+ * etharp_add_static_entry.
+ *
+ * @param ipaddr IP address of the static entry to remove
+ * @return ERR_OK: entry removed
+ *         ERR_MEM: entry wasn't found
+ *         ERR_ARG: entry wasn't a static entry but a dynamic one
+ */
+err_t
+etharp_remove_static_entry(ip_addr_t *ipaddr)
+{
+  s8_t i;
+  LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("etharp_remove_static_entry: %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
+    ip4_addr1_16(ipaddr), ip4_addr2_16(ipaddr), ip4_addr3_16(ipaddr), ip4_addr4_16(ipaddr)));
+
+  /* find or create ARP entry */
+  i = find_entry(ipaddr, ETHARP_FLAG_FIND_ONLY);
+  /* bail out if no entry could be found */
+  if (i < 0) {
+    return (err_t)i;
+  }
+
+  if ((arp_table[i].state != ETHARP_STATE_STABLE) ||
+    (arp_table[i].static_entry == 0)) {
+    /* entry wasn't a static entry, cannot remove it */
+    return ERR_ARG;
+  }
+  /* entry found, free it */
+  free_entry(i);
+  return ERR_OK;
+}
+#endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
+
+/**
+ * Finds (stable) ethernet/IP address pair from ARP table
+ * using interface and IP address index.
+ * @note the addresses in the ARP table are in network order!
+ *
+ * @param netif points to interface index
+ * @param ipaddr points to the (network order) IP address index
+ * @param eth_ret points to return pointer
+ * @param ip_ret points to return pointer
+ * @return table index if found, -1 otherwise
+ */
+s8_t
+etharp_find_addr(struct netif *netif, ip_addr_t *ipaddr,
+         struct eth_addr **eth_ret, ip_addr_t **ip_ret)
+{
+  s8_t i;
+
+  LWIP_ASSERT("eth_ret != NULL && ip_ret != NULL",
+    eth_ret != NULL && ip_ret != NULL);
+
+  LWIP_UNUSED_ARG(netif);
+
+  i = find_entry(ipaddr, ETHARP_FLAG_FIND_ONLY);
+  if((i >= 0) && arp_table[i].state == ETHARP_STATE_STABLE) {
+      *eth_ret = &arp_table[i].ethaddr;
+      *ip_ret = &arp_table[i].ipaddr;
+      return i;
+  }
+  return -1;
+}
+
+#if ETHARP_TRUST_IP_MAC
+/**
+ * Updates the ARP table using the given IP packet.
+ *
+ * Uses the incoming IP packet's source address to update the
+ * ARP cache for the local network. The function does not alter
+ * or free the packet. This function must be called before the
+ * packet p is passed to the IP layer.
+ *
+ * @param netif The lwIP network interface on which the IP packet pbuf arrived.
+ * @param p The IP packet that arrived on netif.
+ *
+ * @return NULL
+ *
+ * @see pbuf_free()
+ */
+static void
+etharp_ip_input(struct netif *netif, struct pbuf *p)
+{
+  struct eth_hdr *ethhdr;
+  struct ip_hdr *iphdr;
+  ip_addr_t iphdr_src;
+  LWIP_ERROR("netif != NULL", (netif != NULL), return;);
+
+  /* Only insert an entry if the source IP address of the
+     incoming IP packet comes from a host on the local network. */
+  ethhdr = (struct eth_hdr *)p->payload;
+  iphdr = (struct ip_hdr *)((u8_t*)ethhdr + SIZEOF_ETH_HDR);
+#if ETHARP_SUPPORT_VLAN
+  if (ethhdr->type == ETHTYPE_VLAN) {
+    iphdr = (struct ip_hdr *)((u8_t*)ethhdr + SIZEOF_ETH_HDR + SIZEOF_VLAN_HDR);
+  }
+#endif /* ETHARP_SUPPORT_VLAN */
+
+  ip_addr_copy(iphdr_src, iphdr->src);
+
+  /* source is not on the local network? */
+  if (!ip_addr_netcmp(&iphdr_src, &(netif->ip_addr), &(netif->netmask))) {
+    /* do nothing */
+    return;
+  }
+
+  LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("etharp_ip_input: updating ETHARP table.\n"));
+  /* update the source IP address in the cache, if present */
+  /* @todo We could use ETHARP_FLAG_TRY_HARD if we think we are going to talk
+   * back soon (for example, if the destination IP address is ours. */
+  update_arp_entry(netif, &iphdr_src, &(ethhdr->src), ETHARP_FLAG_FIND_ONLY);
+}
+#endif /* ETHARP_TRUST_IP_MAC */
+
+/**
+ * Responds to ARP requests to us. Upon ARP replies to us, add entry to cache  
+ * send out queued IP packets. Updates cache with snooped address pairs.
+ *
+ * Should be called for incoming ARP packets. The pbuf in the argument
+ * is freed by this function.
+ *
+ * @param netif The lwIP network interface on which the ARP packet pbuf arrived.
+ * @param ethaddr Ethernet address of netif.
+ * @param p The ARP packet that arrived on netif. Is freed by this function.
+ *
+ * @return NULL
+ *
+ * @see pbuf_free()
+ */
+static void
+etharp_arp_input(struct netif *netif, struct eth_addr *ethaddr, struct pbuf *p)
+{
+  struct etharp_hdr *hdr;
+  struct eth_hdr *ethhdr;
+  /* these are aligned properly, whereas the ARP header fields might not be */
+  ip_addr_t sipaddr, dipaddr;
+  u8_t for_us;
+#if LWIP_AUTOIP
+  const u8_t * ethdst_hwaddr;
+#endif /* LWIP_AUTOIP */
+
+  LWIP_ERROR("netif != NULL", (netif != NULL), return;);
+
+  /* drop short ARP packets: we have to check for p->len instead of p->tot_len here
+     since a struct etharp_hdr is pointed to p->payload, so it musn't be chained! */
+  if (p->len < SIZEOF_ETHARP_PACKET) {
+    LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_WARNING,
+      ("etharp_arp_input: packet dropped, too short (%"S16_F"/%"S16_F")\n", p->tot_len,
+      (s16_t)SIZEOF_ETHARP_PACKET));
+    ETHARP_STATS_INC(etharp.lenerr);
+    ETHARP_STATS_INC(etharp.drop);
+    pbuf_free(p);
+    return;
+  }
+
+  ethhdr = (struct eth_hdr *)p->payload;
+  hdr = (struct etharp_hdr *)((u8_t*)ethhdr + SIZEOF_ETH_HDR);
+#if ETHARP_SUPPORT_VLAN
+  if (ethhdr->type == ETHTYPE_VLAN) {
+    hdr = (struct etharp_hdr *)(((u8_t*)ethhdr) + SIZEOF_ETH_HDR + SIZEOF_VLAN_HDR);
+  }
+#endif /* ETHARP_SUPPORT_VLAN */
+
+  /* RFC 826 "Packet Reception": */
+  if ((hdr->hwtype != PP_HTONS(HWTYPE_ETHERNET)) ||
+      (hdr->hwlen != ETHARP_HWADDR_LEN) ||
+      (hdr->protolen != sizeof(ip_addr_t)) ||
+      (hdr->proto != PP_HTONS(ETHTYPE_IP)) ||
+      (ethhdr->type != PP_HTONS(ETHTYPE_ARP)))  {
+    LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_WARNING,
+      ("etharp_arp_input: packet dropped, wrong hw type, hwlen, proto, protolen or ethernet type (%"U16_F"/%"U16_F"/%"U16_F"/%"U16_F"/%"U16_F")\n",
+      hdr->hwtype, hdr->hwlen, hdr->proto, hdr->protolen, ethhdr->type));
+    ETHARP_STATS_INC(etharp.proterr);
+    ETHARP_STATS_INC(etharp.drop);
+    pbuf_free(p);
+    return;
+  }
+  ETHARP_STATS_INC(etharp.recv);
+
+#if LWIP_AUTOIP
+  /* We have to check if a host already has configured our random
+   * created link local address and continously check if there is
+   * a host with this IP-address so we can detect collisions */
+  autoip_arp_reply(netif, hdr);
+#endif /* LWIP_AUTOIP */
+
+  /* Copy struct ip_addr2 to aligned ip_addr, to support compilers without
+   * structure packing (not using structure copy which breaks strict-aliasing rules). */
+  IPADDR2_COPY(&sipaddr, &hdr->sipaddr);
+  IPADDR2_COPY(&dipaddr, &hdr->dipaddr);
+
+  /* this interface is not configured? */
+  if (ip_addr_isany(&netif->ip_addr)) {
+    for_us = 0;
+  } else {
+    /* ARP packet directed to us? */
+    for_us = (u8_t)ip_addr_cmp(&dipaddr, &(netif->ip_addr));
+  }
+
+  /* ARP message directed to us?
+      -> add IP address in ARP cache; assume requester wants to talk to us,
+         can result in directly sending the queued packets for this host.
+     ARP message not directed to us?
+      ->  update the source IP address in the cache, if present */
+  update_arp_entry(netif, &sipaddr, &(hdr->shwaddr),
+                   for_us ? ETHARP_FLAG_TRY_HARD : ETHARP_FLAG_FIND_ONLY);
+
+  /* now act on the message itself */
+  switch (hdr->opcode) {
+  /* ARP request? */
+  case PP_HTONS(ARP_REQUEST):
+    /* ARP request. If it asked for our address, we send out a
+     * reply. In any case, we time-stamp any existing ARP entry,
+     * and possiby send out an IP packet that was queued on it. */
+
+    LWIP_DEBUGF (ETHARP_DEBUG | LWIP_DBG_TRACE, ("etharp_arp_input: incoming ARP request\n"));
+    /* ARP request for our address? */
+    if (for_us) {
+
+      LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("etharp_arp_input: replying to ARP request for our IP address\n"));
+      /* Re-use pbuf to send ARP reply.
+         Since we are re-using an existing pbuf, we can't call etharp_raw since
+         that would allocate a new pbuf. */
+      hdr->opcode = htons(ARP_REPLY);
+
+      IPADDR2_COPY(&hdr->dipaddr, &hdr->sipaddr);
+      IPADDR2_COPY(&hdr->sipaddr, &netif->ip_addr);
+
+      LWIP_ASSERT("netif->hwaddr_len must be the same as ETHARP_HWADDR_LEN for etharp!",
+                  (netif->hwaddr_len == ETHARP_HWADDR_LEN));
+#if LWIP_AUTOIP
+      /* If we are using Link-Local, all ARP packets that contain a Link-Local
+       * 'sender IP address' MUST be sent using link-layer broadcast instead of
+       * link-layer unicast. (See RFC3927 Section 2.5, last paragraph) */
+      ethdst_hwaddr = ip_addr_islinklocal(&netif->ip_addr) ? (u8_t*)(ethbroadcast.addr) : hdr->shwaddr.addr;
+#endif /* LWIP_AUTOIP */
+
+      ETHADDR16_COPY(&hdr->dhwaddr, &hdr->shwaddr);
+#if LWIP_AUTOIP
+      ETHADDR16_COPY(&ethhdr->dest, ethdst_hwaddr);
+#else  /* LWIP_AUTOIP */
+      ETHADDR16_COPY(&ethhdr->dest, &hdr->shwaddr);
+#endif /* LWIP_AUTOIP */
+      ETHADDR16_COPY(&hdr->shwaddr, ethaddr);
+      ETHADDR16_COPY(&ethhdr->src, ethaddr);
+
+      /* hwtype, hwaddr_len, proto, protolen and the type in the ethernet header
+         are already correct, we tested that before */
+
+      /* return ARP reply */
+      netif->linkoutput(netif, p);
+    /* we are not configured? */
+    } else if (ip_addr_isany(&netif->ip_addr)) {
+      /* { for_us == 0 and netif->ip_addr.addr == 0 } */
+      LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("etharp_arp_input: we are unconfigured, ARP request ignored.\n"));
+    /* request was not directed to us */
+    } else {
+      /* { for_us == 0 and netif->ip_addr.addr != 0 } */
+      LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("etharp_arp_input: ARP request was not for us.\n"));
+    }
+    break;
+  case PP_HTONS(ARP_REPLY):
+    /* ARP reply. We already updated the ARP cache earlier. */
+    LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("etharp_arp_input: incoming ARP reply\n"));
+#if (LWIP_DHCP && DHCP_DOES_ARP_CHECK)
+    /* DHCP wants to know about ARP replies from any host with an
+     * IP address also offered to us by the DHCP server. We do not
+     * want to take a duplicate IP address on a single network.
+     * @todo How should we handle redundant (fail-over) interfaces? */
+    dhcp_arp_reply(netif, &sipaddr);
+#endif /* (LWIP_DHCP && DHCP_DOES_ARP_CHECK) */
+    break;
+  default:
+    LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("etharp_arp_input: ARP unknown opcode type %"S16_F"\n", htons(hdr->opcode)));
+    ETHARP_STATS_INC(etharp.err);
+    break;
+  }
+  /* free ARP packet */
+  pbuf_free(p);
+}
+
+/**
+ * Resolve and fill-in Ethernet address header for outgoing IP packet.
+ *
+ * For IP multicast and broadcast, corresponding Ethernet addresses
+ * are selected and the packet is transmitted on the link.
+ *
+ * For unicast addresses, the packet is submitted to etharp_query(). In
+ * case the IP address is outside the local network, the IP address of
+ * the gateway is used.
+ *
+ * @param netif The lwIP network interface which the IP packet will be sent on.
+ * @param q The pbuf(s) containing the IP packet to be sent.
+ * @param ipaddr The IP address of the packet destination.
+ *
+ * @return
+ * - ERR_RTE No route to destination (no gateway to external networks),
+ * or the return type of either etharp_query() or etharp_send_ip().
+ */
+err_t
+etharp_output(struct netif *netif, struct pbuf *q, ip_addr_t *ipaddr)
+{
+  struct eth_addr *dest, mcastaddr;
+
+  /* make room for Ethernet header - should not fail */
+  if (pbuf_header(q, sizeof(struct eth_hdr)) != 0) {
+    /* bail out */
+    LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_SERIOUS,
+      ("etharp_output: could not allocate room for header.\n"));
+    LINK_STATS_INC(link.lenerr);
+    return ERR_BUF;
+  }
+
+  /* assume unresolved Ethernet address */
+  dest = NULL;
+  /* Determine on destination hardware address. Broadcasts and multicasts
+   * are special, other IP addresses are looked up in the ARP table. */
+
+  /* broadcast destination IP address? */
+  if (ip_addr_isbroadcast(ipaddr, netif)) {
+    /* broadcast on Ethernet also */
+    dest = (struct eth_addr *)&ethbroadcast;
+  /* multicast destination IP address? */
+  } else if (ip_addr_ismulticast(ipaddr)) {
+    /* Hash IP multicast address to MAC address.*/
+    mcastaddr.addr[0] = 0x01;
+    mcastaddr.addr[1] = 0x00;
+    mcastaddr.addr[2] = 0x5e;
+    mcastaddr.addr[3] = ip4_addr2(ipaddr) & 0x7f;
+    mcastaddr.addr[4] = ip4_addr3(ipaddr);
+    mcastaddr.addr[5] = ip4_addr4(ipaddr);
+    /* destination Ethernet address is multicast */
+    dest = &mcastaddr;
+  /* unicast destination IP address? */
+  } else {
+    /* outside local network? */
+    if (!ip_addr_netcmp(ipaddr, &(netif->ip_addr), &(netif->netmask)) &&
+        !ip_addr_islinklocal(ipaddr)) {
+      /* interface has default gateway? */
+      if (!ip_addr_isany(&netif->gw)) {
+        /* send to hardware address of default gateway IP address */
+        ipaddr = &(netif->gw);
+      /* no default gateway available */
+      } else {
+        /* no route to destination error (default gateway missing) */
+        return ERR_RTE;
+      }
+    }
+#if LWIP_NETIF_HWADDRHINT
+    if (netif->addr_hint != NULL) {
+      /* per-pcb cached entry was given */
+      u8_t etharp_cached_entry = *(netif->addr_hint);
+      if (etharp_cached_entry < ARP_TABLE_SIZE) {
+#endif /* LWIP_NETIF_HWADDRHINT */
+        if ((arp_table[etharp_cached_entry].state == ETHARP_STATE_STABLE) &&
+            (ip_addr_cmp(ipaddr, &arp_table[etharp_cached_entry].ipaddr))) {
+          /* the per-pcb-cached entry is stable and the right one! */
+          ETHARP_STATS_INC(etharp.cachehit);
+          return etharp_send_ip(netif, q, (struct eth_addr*)(netif->hwaddr),
+            &arp_table[etharp_cached_entry].ethaddr);
+        }
+#if LWIP_NETIF_HWADDRHINT
+      }
+    }
+#endif /* LWIP_NETIF_HWADDRHINT */
+    /* queue on destination Ethernet address belonging to ipaddr */
+    return etharp_query(netif, ipaddr, q);
+  }
+
+  /* continuation for multicast/broadcast destinations */
+  /* obtain source Ethernet address of the given interface */
+  /* send packet directly on the link */
+  return etharp_send_ip(netif, q, (struct eth_addr*)(netif->hwaddr), dest);
+}
+
+/**
+ * Send an ARP request for the given IP address and/or queue a packet.
+ *
+ * If the IP address was not yet in the cache, a pending ARP cache entry
+ * is added and an ARP request is sent for the given address. The packet
+ * is queued on this entry.
+ *
+ * If the IP address was already pending in the cache, a new ARP request
+ * is sent for the given address. The packet is queued on this entry.
+ *
+ * If the IP address was already stable in the cache, and a packet is
+ * given, it is directly sent and no ARP request is sent out. 
+ * 
+ * If the IP address was already stable in the cache, and no packet is
+ * given, an ARP request is sent out.
+ * 
+ * @param netif The lwIP network interface on which ipaddr
+ * must be queried for.
+ * @param ipaddr The IP address to be resolved.
+ * @param q If non-NULL, a pbuf that must be delivered to the IP address.
+ * q is not freed by this function.
+ *
+ * @note q must only be ONE packet, not a packet queue!
+ *
+ * @return
+ * - ERR_BUF Could not make room for Ethernet header.
+ * - ERR_MEM Hardware address unknown, and no more ARP entries available
+ *   to query for address or queue the packet.
+ * - ERR_MEM Could not queue packet due to memory shortage.
+ * - ERR_RTE No route to destination (no gateway to external networks).
+ * - ERR_ARG Non-unicast address given, those will not appear in ARP cache.
+ *
+ */
+err_t
+etharp_query(struct netif *netif, ip_addr_t *ipaddr, struct pbuf *q)
+{
+  struct eth_addr * srcaddr = (struct eth_addr *)netif->hwaddr;
+  err_t result = ERR_MEM;
+  s8_t i; /* ARP entry index */
+
+  /* non-unicast address? */
+  if (ip_addr_isbroadcast(ipaddr, netif) ||
+      ip_addr_ismulticast(ipaddr) ||
+      ip_addr_isany(ipaddr)) {
+    LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("etharp_query: will not add non-unicast IP address to ARP cache\n"));
+    return ERR_ARG;
+  }
+
+  /* find entry in ARP cache, ask to create entry if queueing packet */
+  i = find_entry(ipaddr, ETHARP_FLAG_TRY_HARD);
+
+  /* could not find or create entry? */
+  if (i < 0) {
+    LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("etharp_query: could not create ARP entry\n"));
+    if (q) {
+      LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("etharp_query: packet dropped\n"));
+      ETHARP_STATS_INC(etharp.memerr);
+    }
+    return (err_t)i;
+  }
+
+  /* mark a fresh entry as pending (we just sent a request) */
+  if (arp_table[i].state == ETHARP_STATE_EMPTY) {
+    arp_table[i].state = ETHARP_STATE_PENDING;
+  }
+
+  /* { i is either a STABLE or (new or existing) PENDING entry } */
+  LWIP_ASSERT("arp_table[i].state == PENDING or STABLE",
+  ((arp_table[i].state == ETHARP_STATE_PENDING) ||
+   (arp_table[i].state == ETHARP_STATE_STABLE)));
+
+  /* do we have a pending entry? or an implicit query request? */
+  if ((arp_table[i].state == ETHARP_STATE_PENDING) || (q == NULL)) {
+    /* try to resolve it; send out ARP request */
+    result = etharp_request(netif, ipaddr);
+    if (result != ERR_OK) {
+      /* ARP request couldn't be sent */
+      /* We don't re-send arp request in etharp_tmr, but we still queue packets,
+         since this failure could be temporary, and the next packet calling
+         etharp_query again could lead to sending the queued packets. */
+    }
+    if (q == NULL) {
+      return result;
+    }
+  }
+
+  /* packet given? */
+  LWIP_ASSERT("q != NULL", q != NULL);
+  /* stable entry? */
+  if (arp_table[i].state == ETHARP_STATE_STABLE) {
+    /* we have a valid IP->Ethernet address mapping */
+    ETHARP_SET_HINT(netif, i);
+    /* send the packet */
+    result = etharp_send_ip(netif, q, srcaddr, &(arp_table[i].ethaddr));
+  /* pending entry? (either just created or already pending */
+  } else if (arp_table[i].state == ETHARP_STATE_PENDING) {
+#if ARP_QUEUEING /* queue the given q packet */
+    struct pbuf *p;
+    int copy_needed = 0;
+    /* IF q includes a PBUF_REF, PBUF_POOL or PBUF_RAM, we have no choice but
+     * to copy the whole queue into a new PBUF_RAM (see bug #11400) 
+     * PBUF_ROMs can be left as they are, since ROM must not get changed. */
+    p = q;
+    while (p) {
+      LWIP_ASSERT("no packet queues allowed!", (p->len != p->tot_len) || (p->next == 0));
+      if(p->type != PBUF_ROM) {
+        copy_needed = 1;
+        break;
+      }
+      p = p->next;
+    }
+    if(copy_needed) {
+      /* copy the whole packet into new pbufs */
+      p = pbuf_alloc(PBUF_RAW, p->tot_len, PBUF_RAM);
+      if(p != NULL) {
+        if (pbuf_copy(p, q) != ERR_OK) {
+          pbuf_free(p);
+          p = NULL;
+        }
+      }
+    } else {
+      /* referencing the old pbuf is enough */
+      p = q;
+      pbuf_ref(p);
+    }
+    /* packet could be taken over? */
+    if (p != NULL) {
+      /* queue packet ... */
+      struct etharp_q_entry *new_entry;
+      /* allocate a new arp queue entry */
+      new_entry = (struct etharp_q_entry *)memp_malloc(MEMP_ARP_QUEUE);
+      if (new_entry != NULL) {
+        new_entry->next = 0;
+        new_entry->p = p;
+        if(arp_table[i].q != NULL) {
+          /* queue was already existent, append the new entry to the end */
+          struct etharp_q_entry *r;
+          r = arp_table[i].q;
+          while (r->next != NULL) {
+            r = r->next;
+          }
+          r->next = new_entry;
+        } else {
+          /* queue did not exist, first item in queue */
+          arp_table[i].q = new_entry;
+        }
+        LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("etharp_query: queued packet %p on ARP entry %"S16_F"\n", (void *)q, (s16_t)i));
+        result = ERR_OK;
+      } else {
+        /* the pool MEMP_ARP_QUEUE is empty */
+        pbuf_free(p);
+        LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("etharp_query: could not queue a copy of PBUF_REF packet %p (out of memory)\n", (void *)q));
+        /* { result == ERR_MEM } through initialization */
+      }
+    } else {
+      ETHARP_STATS_INC(etharp.memerr);
+      LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("etharp_query: could not queue a copy of PBUF_REF packet %p (out of memory)\n", (void *)q));
+      /* { result == ERR_MEM } through initialization */
+    }
+#else /* ARP_QUEUEING */
+    /* q && state == PENDING && ARP_QUEUEING == 0 => result = ERR_MEM */
+    /* { result == ERR_MEM } through initialization */
+    LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("etharp_query: Ethernet destination address unknown, queueing disabled, packet %p dropped\n", (void *)q));
+#endif /* ARP_QUEUEING */
+  }
+  return result;
+}
+
+/**
+ * Send a raw ARP packet (opcode and all addresses can be modified)
+ *
+ * @param netif the lwip network interface on which to send the ARP packet
+ * @param ethsrc_addr the source MAC address for the ethernet header
+ * @param ethdst_addr the destination MAC address for the ethernet header
+ * @param hwsrc_addr the source MAC address for the ARP protocol header
+ * @param ipsrc_addr the source IP address for the ARP protocol header
+ * @param hwdst_addr the destination MAC address for the ARP protocol header
+ * @param ipdst_addr the destination IP address for the ARP protocol header
+ * @param opcode the type of the ARP packet
+ * @return ERR_OK if the ARP packet has been sent
+ *         ERR_MEM if the ARP packet couldn't be allocated
+ *         any other err_t on failure
+ */
+#if !LWIP_AUTOIP
+static
+#endif /* LWIP_AUTOIP */
+err_t
+etharp_raw(struct netif *netif, const struct eth_addr *ethsrc_addr,
+           const struct eth_addr *ethdst_addr,
+           const struct eth_addr *hwsrc_addr, const ip_addr_t *ipsrc_addr,
+           const struct eth_addr *hwdst_addr, const ip_addr_t *ipdst_addr,
+           const u16_t opcode)
+{
+  struct pbuf *p;
+  err_t result = ERR_OK;
+  struct eth_hdr *ethhdr;
+  struct etharp_hdr *hdr;
+#if LWIP_AUTOIP
+  const u8_t * ethdst_hwaddr;
+#endif /* LWIP_AUTOIP */
+
+  /* allocate a pbuf for the outgoing ARP request packet */
+  p = pbuf_alloc(PBUF_RAW, SIZEOF_ETHARP_PACKET, PBUF_RAM);
+  /* could allocate a pbuf for an ARP request? */
+  if (p == NULL) {
+    LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_SERIOUS,
+      ("etharp_raw: could not allocate pbuf for ARP request.\n"));
+    ETHARP_STATS_INC(etharp.memerr);
+    return ERR_MEM;
+  }
+  LWIP_ASSERT("check that first pbuf can hold struct etharp_hdr",
+              (p->len >= SIZEOF_ETHARP_PACKET));
+
+  ethhdr = (struct eth_hdr *)p->payload;
+  hdr = (struct etharp_hdr *)((u8_t*)ethhdr + SIZEOF_ETH_HDR);
+  LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("etharp_raw: sending raw ARP packet.\n"));
+  hdr->opcode = htons(opcode);
+
+  LWIP_ASSERT("netif->hwaddr_len must be the same as ETHARP_HWADDR_LEN for etharp!",
+              (netif->hwaddr_len == ETHARP_HWADDR_LEN));
+#if LWIP_AUTOIP
+  /* If we are using Link-Local, all ARP packets that contain a Link-Local
+   * 'sender IP address' MUST be sent using link-layer broadcast instead of
+   * link-layer unicast. (See RFC3927 Section 2.5, last paragraph) */
+  ethdst_hwaddr = ip_addr_islinklocal(ipsrc_addr) ? (u8_t*)(ethbroadcast.addr) : ethdst_addr->addr;
+#endif /* LWIP_AUTOIP */
+  /* Write the ARP MAC-Addresses */
+  ETHADDR16_COPY(&hdr->shwaddr, hwsrc_addr);
+  ETHADDR16_COPY(&hdr->dhwaddr, hwdst_addr);
+  /* Write the Ethernet MAC-Addresses */
+#if LWIP_AUTOIP
+  ETHADDR16_COPY(&ethhdr->dest, ethdst_hwaddr);
+#else  /* LWIP_AUTOIP */
+  ETHADDR16_COPY(&ethhdr->dest, ethdst_addr);
+#endif /* LWIP_AUTOIP */
+  ETHADDR16_COPY(&ethhdr->src, ethsrc_addr);
+  /* Copy struct ip_addr2 to aligned ip_addr, to support compilers without
+   * structure packing. */ 
+  IPADDR2_COPY(&hdr->sipaddr, ipsrc_addr);
+  IPADDR2_COPY(&hdr->dipaddr, ipdst_addr);
+
+  hdr->hwtype = PP_HTONS(HWTYPE_ETHERNET);
+  hdr->proto = PP_HTONS(ETHTYPE_IP);
+  /* set hwlen and protolen */
+  hdr->hwlen = ETHARP_HWADDR_LEN;
+  hdr->protolen = sizeof(ip_addr_t);
+
+  ethhdr->type = PP_HTONS(ETHTYPE_ARP);
+  /* send ARP query */
+  result = netif->linkoutput(netif, p);
+  ETHARP_STATS_INC(etharp.xmit);
+  /* free ARP query packet */
+  pbuf_free(p);
+  p = NULL;
+  /* could not allocate pbuf for ARP request */
+
+  return result;
+}
+
+/**
+ * Send an ARP request packet asking for ipaddr.
+ *
+ * @param netif the lwip network interface on which to send the request
+ * @param ipaddr the IP address for which to ask
+ * @return ERR_OK if the request has been sent
+ *         ERR_MEM if the ARP packet couldn't be allocated
+ *         any other err_t on failure
+ */
+err_t
+etharp_request(struct netif *netif, ip_addr_t *ipaddr)
+{
+  LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("etharp_request: sending ARP request.\n"));
+  return etharp_raw(netif, (struct eth_addr *)netif->hwaddr, &ethbroadcast,
+                    (struct eth_addr *)netif->hwaddr, &netif->ip_addr, &ethzero,
+                    ipaddr, ARP_REQUEST);
+}
+#endif /* LWIP_ARP */
+
+/**
+ * Process received ethernet frames. Using this function instead of directly
+ * calling ip_input and passing ARP frames through etharp in ethernetif_input,
+ * the ARP cache is protected from concurrent access.
+ *
+ * @param p the recevied packet, p->payload pointing to the ethernet header
+ * @param netif the network interface on which the packet was received
+ */
+err_t
+ethernet_input(struct pbuf *p, struct netif *netif)
+{
+  struct eth_hdr* ethhdr;
+  u16_t type;
+
+  /* points to packet payload, which starts with an Ethernet header */
+  ethhdr = (struct eth_hdr *)p->payload;
+  LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE,
+    ("ethernet_input: dest:%"X8_F":%"X8_F":%"X8_F":%"X8_F":%"X8_F":%"X8_F", src:%"X8_F":%"X8_F":%"X8_F":%"X8_F":%"X8_F":%"X8_F", type:%"X16_F"\n",
+     (unsigned)ethhdr->dest.addr[0], (unsigned)ethhdr->dest.addr[1], (unsigned)ethhdr->dest.addr[2],
+     (unsigned)ethhdr->dest.addr[3], (unsigned)ethhdr->dest.addr[4], (unsigned)ethhdr->dest.addr[5],
+     (unsigned)ethhdr->src.addr[0], (unsigned)ethhdr->src.addr[1], (unsigned)ethhdr->src.addr[2],
+     (unsigned)ethhdr->src.addr[3], (unsigned)ethhdr->src.addr[4], (unsigned)ethhdr->src.addr[5],
+     (unsigned)htons(ethhdr->type)));
+
+  type = ethhdr->type;
+#if ETHARP_SUPPORT_VLAN
+  if (type == PP_HTONS(ETHTYPE_VLAN)) {
+    struct eth_vlan_hdr *vlan = (struct eth_vlan_hdr*)(((char*)ethhdr) + SIZEOF_ETH_HDR);
+#ifdef ETHARP_VLAN_CHECK /* if not, allow all VLANs */
+    if (VLAN_ID(vlan) != ETHARP_VLAN_CHECK) {
+      /* silently ignore this packet: not for our VLAN */
+      pbuf_free(p);
+      return ERR_OK;
+    }
+#endif /* ETHARP_VLAN_CHECK */
+    type = vlan->tpid;
+  }
+#endif /* ETHARP_SUPPORT_VLAN */
+
+#if LWIP_ARP_FILTER_NETIF
+  netif = LWIP_ARP_FILTER_NETIF_FN(p, netif, htons(type));
+#endif /* LWIP_ARP_FILTER_NETIF*/
+
+  switch (type) {
+#if LWIP_ARP
+    /* IP packet? */
+    case PP_HTONS(ETHTYPE_IP):
+      if (!(netif->flags & NETIF_FLAG_ETHARP)) {
+        goto free_and_return;
+      }
+#if ETHARP_TRUST_IP_MAC
+      /* update ARP table */
+      etharp_ip_input(netif, p);
+#endif /* ETHARP_TRUST_IP_MAC */
+      /* skip Ethernet header */
+      if(pbuf_header(p, -(s16_t)SIZEOF_ETH_HDR)) {
+        LWIP_ASSERT("Can't move over header in packet", 0);
+        goto free_and_return;
+      } else {
+        /* pass to IP layer */
+        ip_input(p, netif);
+      }
+      break;
+      
+    case PP_HTONS(ETHTYPE_ARP):
+      if (!(netif->flags & NETIF_FLAG_ETHARP)) {
+        goto free_and_return;
+      }
+      /* pass p to ARP module */
+      etharp_arp_input(netif, (struct eth_addr*)(netif->hwaddr), p);
+      break;
+#endif /* LWIP_ARP */
+#if PPPOE_SUPPORT
+    case PP_HTONS(ETHTYPE_PPPOEDISC): /* PPP Over Ethernet Discovery Stage */
+      pppoe_disc_input(netif, p);
+      break;
+
+    case PP_HTONS(ETHTYPE_PPPOE): /* PPP Over Ethernet Session Stage */
+      pppoe_data_input(netif, p);
+      break;
+#endif /* PPPOE_SUPPORT */
+
+    default:
+      ETHARP_STATS_INC(etharp.proterr);
+      ETHARP_STATS_INC(etharp.drop);
+      goto free_and_return;
+  }
+
+  /* This means the pbuf is freed or consumed,
+     so the caller doesn't have to free it again */
+  return ERR_OK;
+
+free_and_return:
+  pbuf_free(p);
+  return ERR_OK;
+}
+#endif /* LWIP_ARP || LWIP_ETHERNET */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwip/netif/ethernetif.c	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,318 @@
+/**
+ * @file
+ * Ethernet Interface Skeleton
+ *
+ */
+
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+
+/*
+ * This file is a skeleton for developing Ethernet network interface
+ * drivers for lwIP. Add code to the low_level functions and do a
+ * search-and-replace for the word "ethernetif" to replace it with
+ * something that better describes your network interface.
+ */
+
+#include "lwip/opt.h"
+
+#if 0 /* don't build, this is only a skeleton, see previous comment */
+
+#include "lwip/def.h"
+#include "lwip/mem.h"
+#include "lwip/pbuf.h"
+#include "lwip/sys.h"
+#include <lwip/stats.h>
+#include <lwip/snmp.h>
+#include "netif/etharp.h"
+#include "netif/ppp_oe.h"
+
+/* Define those to better describe your network interface. */
+#define IFNAME0 'e'
+#define IFNAME1 'n'
+
+/**
+ * Helper struct to hold private data used to operate your ethernet interface.
+ * Keeping the ethernet address of the MAC in this struct is not necessary
+ * as it is already kept in the struct netif.
+ * But this is only an example, anyway...
+ */
+struct ethernetif {
+  struct eth_addr *ethaddr;
+  /* Add whatever per-interface state that is needed here. */
+};
+
+/* Forward declarations. */
+static void  ethernetif_input(struct netif *netif);
+
+/**
+ * In this function, the hardware should be initialized.
+ * Called from ethernetif_init().
+ *
+ * @param netif the already initialized lwip network interface structure
+ *        for this ethernetif
+ */
+static void
+low_level_init(struct netif *netif)
+{
+  struct ethernetif *ethernetif = netif->state;
+  
+  /* set MAC hardware address length */
+  netif->hwaddr_len = ETHARP_HWADDR_LEN;
+
+  /* set MAC hardware address */
+  netif->hwaddr[0] = ;
+  ...
+  netif->hwaddr[5] = ;
+
+  /* maximum transfer unit */
+  netif->mtu = 1500;
+  
+  /* device capabilities */
+  /* don't set NETIF_FLAG_ETHARP if this device is not an ethernet one */
+  netif->flags = NETIF_FLAG_BROADCAST | NETIF_FLAG_ETHARP | NETIF_FLAG_LINK_UP;
+ 
+  /* Do whatever else is needed to initialize interface. */  
+}
+
+/**
+ * This function should do the actual transmission of the packet. The packet is
+ * contained in the pbuf that is passed to the function. This pbuf
+ * might be chained.
+ *
+ * @param netif the lwip network interface structure for this ethernetif
+ * @param p the MAC packet to send (e.g. IP packet including MAC addresses and type)
+ * @return ERR_OK if the packet could be sent
+ *         an err_t value if the packet couldn't be sent
+ *
+ * @note Returning ERR_MEM here if a DMA queue of your MAC is full can lead to
+ *       strange results. You might consider waiting for space in the DMA queue
+ *       to become availale since the stack doesn't retry to send a packet
+ *       dropped because of memory failure (except for the TCP timers).
+ */
+
+static err_t
+low_level_output(struct netif *netif, struct pbuf *p)
+{
+  struct ethernetif *ethernetif = netif->state;
+  struct pbuf *q;
+
+  initiate transfer();
+  
+#if ETH_PAD_SIZE
+  pbuf_header(p, -ETH_PAD_SIZE); /* drop the padding word */
+#endif
+
+  for(q = p; q != NULL; q = q->next) {
+    /* Send the data from the pbuf to the interface, one pbuf at a
+       time. The size of the data in each pbuf is kept in the ->len
+       variable. */
+    send data from(q->payload, q->len);
+  }
+
+  signal that packet should be sent();
+
+#if ETH_PAD_SIZE
+  pbuf_header(p, ETH_PAD_SIZE); /* reclaim the padding word */
+#endif
+  
+  LINK_STATS_INC(link.xmit);
+
+  return ERR_OK;
+}
+
+/**
+ * Should allocate a pbuf and transfer the bytes of the incoming
+ * packet from the interface into the pbuf.
+ *
+ * @param netif the lwip network interface structure for this ethernetif
+ * @return a pbuf filled with the received packet (including MAC header)
+ *         NULL on memory error
+ */
+static struct pbuf *
+low_level_input(struct netif *netif)
+{
+  struct ethernetif *ethernetif = netif->state;
+  struct pbuf *p, *q;
+  u16_t len;
+
+  /* Obtain the size of the packet and put it into the "len"
+     variable. */
+  len = ;
+
+#if ETH_PAD_SIZE
+  len += ETH_PAD_SIZE; /* allow room for Ethernet padding */
+#endif
+
+  /* We allocate a pbuf chain of pbufs from the pool. */
+  p = pbuf_alloc(PBUF_RAW, len, PBUF_POOL);
+  
+  if (p != NULL) {
+
+#if ETH_PAD_SIZE
+    pbuf_header(p, -ETH_PAD_SIZE); /* drop the padding word */
+#endif
+
+    /* We iterate over the pbuf chain until we have read the entire
+     * packet into the pbuf. */
+    for(q = p; q != NULL; q = q->next) {
+      /* Read enough bytes to fill this pbuf in the chain. The
+       * available data in the pbuf is given by the q->len
+       * variable.
+       * This does not necessarily have to be a memcpy, you can also preallocate
+       * pbufs for a DMA-enabled MAC and after receiving truncate it to the
+       * actually received size. In this case, ensure the tot_len member of the
+       * pbuf is the sum of the chained pbuf len members.
+       */
+      read data into(q->payload, q->len);
+    }
+    acknowledge that packet has been read();
+
+#if ETH_PAD_SIZE
+    pbuf_header(p, ETH_PAD_SIZE); /* reclaim the padding word */
+#endif
+
+    LINK_STATS_INC(link.recv);
+  } else {
+    drop packet();
+    LINK_STATS_INC(link.memerr);
+    LINK_STATS_INC(link.drop);
+  }
+
+  return p;  
+}
+
+/**
+ * This function should be called when a packet is ready to be read
+ * from the interface. It uses the function low_level_input() that
+ * should handle the actual reception of bytes from the network
+ * interface. Then the type of the received packet is determined and
+ * the appropriate input function is called.
+ *
+ * @param netif the lwip network interface structure for this ethernetif
+ */
+static void
+ethernetif_input(struct netif *netif)
+{
+  struct ethernetif *ethernetif;
+  struct eth_hdr *ethhdr;
+  struct pbuf *p;
+
+  ethernetif = netif->state;
+
+  /* move received packet into a new pbuf */
+  p = low_level_input(netif);
+  /* no packet could be read, silently ignore this */
+  if (p == NULL) return;
+  /* points to packet payload, which starts with an Ethernet header */
+  ethhdr = p->payload;
+
+  switch (htons(ethhdr->type)) {
+  /* IP or ARP packet? */
+  case ETHTYPE_IP:
+  case ETHTYPE_ARP:
+#if PPPOE_SUPPORT
+  /* PPPoE packet? */
+  case ETHTYPE_PPPOEDISC:
+  case ETHTYPE_PPPOE:
+#endif /* PPPOE_SUPPORT */
+    /* full packet send to tcpip_thread to process */
+    if (netif->input(p, netif)!=ERR_OK)
+     { LWIP_DEBUGF(NETIF_DEBUG, ("ethernetif_input: IP input error\n"));
+       pbuf_free(p);
+       p = NULL;
+     }
+    break;
+
+  default:
+    pbuf_free(p);
+    p = NULL;
+    break;
+  }
+}
+
+/**
+ * Should be called at the beginning of the program to set up the
+ * network interface. It calls the function low_level_init() to do the
+ * actual setup of the hardware.
+ *
+ * This function should be passed as a parameter to netif_add().
+ *
+ * @param netif the lwip network interface structure for this ethernetif
+ * @return ERR_OK if the loopif is initialized
+ *         ERR_MEM if private data couldn't be allocated
+ *         any other err_t on error
+ */
+err_t
+ethernetif_init(struct netif *netif)
+{
+  struct ethernetif *ethernetif;
+
+  LWIP_ASSERT("netif != NULL", (netif != NULL));
+    
+  ethernetif = mem_malloc(sizeof(struct ethernetif));
+  if (ethernetif == NULL) {
+    LWIP_DEBUGF(NETIF_DEBUG, ("ethernetif_init: out of memory\n"));
+    return ERR_MEM;
+  }
+
+#if LWIP_NETIF_HOSTNAME
+  /* Initialize interface hostname */
+  netif->hostname = "lwip";
+#endif /* LWIP_NETIF_HOSTNAME */
+
+  /*
+   * Initialize the snmp variables and counters inside the struct netif.
+   * The last argument should be replaced with your link speed, in units
+   * of bits per second.
+   */
+  NETIF_INIT_SNMP(netif, snmp_ifType_ethernet_csmacd, LINK_SPEED_OF_YOUR_NETIF_IN_BPS);
+
+  netif->state = ethernetif;
+  netif->name[0] = IFNAME0;
+  netif->name[1] = IFNAME1;
+  /* We directly use etharp_output() here to save a function call.
+   * You can instead declare your own function an call etharp_output()
+   * from it if you have to do some checks before sending (e.g. if link
+   * is available...) */
+  netif->output = etharp_output;
+  netif->linkoutput = low_level_output;
+  
+  ethernetif->ethaddr = (struct eth_addr *)&(netif->hwaddr[0]);
+  
+  /* initialize the hardware */
+  low_level_init(netif);
+
+  return ERR_OK;
+}
+
+#endif /* 0 */
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/netCfg.h	Mon Jan 10 21:03:11 2011 +0000
@@ -0,0 +1,11 @@
+#ifndef NET_CFG_H
+#define NET_GPRS 0
+#define NET_PPP 0
+#define NET_GPRS_MODULE 0
+#define NET_ETH 1
+#define NET_USB_SERIAL 0
+#define NET_CFG_H 1
+#define NET_UMTS 0
+#define NET_USB 0
+#define NET_LWIP_STACK 1
+#endif