Quantum Leaps
Example program for the lwIP TCP/IP stack (library lwip_1_4_0_rc2) and the QP state machine framework (library qp). This program demonstrates use of lwIP in hard real-time applications, in which the TCP/IP stack is used to monitor and configure the embedded device as well as to provide remote user interface (e.g., by means of a web browser). In particular, the lwIP stack, which is not reentrant, is strictly encapsulated inside a dedicated QP state machine object (active object in QP), so interrupt locking around calls to lwIP is unnecessary. Also, the Ethernet interrupt service routine (ISR) runs very fast without performing any lengthy copy operations. All this means that hard-real-time processing can be done at the task level, especially when you use the preemptive QK kernel built into QP for executing your application. No external RTOS component is needed to achieve fully deterministic real-time response of active object tasks prioritized above the lwiP task. The lwIP-QP integration uses exclusively the event-driven lwIP API. The heavyweight Berkeley-like socket API requiring a blocking RTOS and is not used, which results in much better performance of the lwIP stack and less memory consumption. NOTE: This example compiles cleanly, but does not run just yet because the low-level Ethernet driver in the lwIP library needs to be completed. See comments in the lwip_1_4_0_rc2 library for more information.
Diff: lwipmgr.cpp
- Revision:
- 0:84f3d3d7e5d9
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/lwipmgr.cpp Sun Mar 27 16:50:21 2011 +0000
@@ -0,0 +1,326 @@
+//////////////////////////////////////////////////////////////////////////////
+// Product: lwIP-Manager Active Object
+// Last Updated for Version: 4.1.06
+// Date of the Last Update: Feb 21, 2011
+//
+// Q u a n t u m L e a P s
+// ---------------------------
+// innovating embedded systems
+//
+// Copyright (C) 2002-2011 Quantum Leaps, LLC. All rights reserved.
+//
+// This software may be distributed and modified under the terms of the GNU
+// General Public License version 2 (GPL) as published by the Free Software
+// Foundation and appearing in the file GPL.TXT included in the packaging of
+// this file. Please note that GPL Section 2[b] requires that all works based
+// on this software must also be made publicly available under the terms of
+// the GPL ("Copyleft").
+//
+// Alternatively, this software may be distributed and modified under the
+// terms of Quantum Leaps commercial licenses, which expressly supersede
+// the GPL and are specifically designed for licensees interested in
+// retaining the proprietary status of their code.
+//
+// Contact information:
+// Quantum Leaps Web site: http://www.quantum-leaps.com
+// e-mail: info@quantum-leaps.com
+//////////////////////////////////////////////////////////////////////////////
+#include "qp_port.h" // QP-port
+#include "dpp.h" // application events and active objects
+#include "bsp.h" // Board Support Package
+
+#include "lwip/opt.h" // lwIP options come first
+#include "lwip/stats.h"
+#include "lwip/tcp.h"
+#include "lwip/tcp_impl.h"
+#include "lwip/udp.h"
+#include "lwip/tcpip.h"
+#include "lwip/mem.h"
+#include "lwip/autoip.h"
+#include "lwip/dhcp.h"
+
+#include "netif/etharp.h"
+#include "port/eth_driver.h"
+ // utilities added by QL...
+#include "app/httpd.h" // application layer protocols
+
+#include <string.h>
+#include <stdio.h>
+
+Q_DEFINE_THIS_FILE
+
+ // application signals cannot overlap the device-driver signals
+Q_ASSERT_COMPILE(MAX_SIG < DEV_DRIVER_SIG);
+
+#define LWIP_SLOW_TICK_MS TCP_TMR_INTERVAL
+
+// Active object class -------------------------------------------------------
+class LwIPMgr : public QActive {
+
+ QTimeEvt m_te_LWIP_SLOW_TICK;
+ struct netif *m_netif;
+ struct udp_pcb *m_upcb;
+ uint32_t m_ip_addr; // IP address in the native host byte order
+
+#if LWIP_TCP
+ uint32_t m_tcp_tmr;
+#endif
+#if LWIP_ARP
+ uint32_t m_arp_tmr;
+#endif
+#if LWIP_DHCP
+ uint32_t m_dhcp_fine_tmr;
+ uint32_t m_dhcp_coarse_tmr;
+#endif
+#if LWIP_AUTOIP
+ uint32_t m_auto_ip_tmr;
+#endif
+
+public:
+ LwIPMgr(); // ctor
+
+private:
+ static QState initial(LwIPMgr *me, QEvent const *e);
+ static QState running(LwIPMgr *me, QEvent const *e);
+};
+
+
+// Local objects -------------------------------------------------------------
+static LwIPMgr l_lwIPMgr; // the single instance of LwIPMgr AO
+
+// Global-scope objects ------------------------------------------------------
+QActive * const AO_LwIPMgr = (QActive *)&l_lwIPMgr; // "opaque" pointer
+
+// Server-Side Include (SSI) demo ............................................
+static char const * const ssi_tags[] = {
+ "s_xmit",
+ "s_recv",
+ "s_fw",
+ "s_drop",
+ "s_chkerr",
+ "s_lenerr",
+ "s_memerr",
+ "s_rterr",
+ "s_proerr",
+ "s_opterr",
+ "s_err",
+};
+static int ssi_handler(int iIndex, char *pcInsert, int iInsertLen);
+
+// Common Gateway Iinterface (CG) demo .......................................
+static char const *cgi_display(int index, int numParams,
+ char const *param[],
+ char const *value[]);
+static tCGI const cgi_handlers[] = {
+ { "/display.cgi", &cgi_display },
+};
+
+// UDP handler ...............................................................
+static void udp_rx_handler(void *arg, struct udp_pcb *upcb,
+ struct pbuf *p, struct ip_addr *addr, u16_t port);
+//............................................................................
+LwIPMgr::LwIPMgr()
+ : QActive((QStateHandler)&LwIPMgr::initial),
+ m_te_LWIP_SLOW_TICK(LWIP_SLOW_TICK_SIG)
+{}
+//............................................................................
+QState LwIPMgr::initial(LwIPMgr *me, QEvent const * /*e*/) {
+ // initialize the Ethernet Driver
+ me->m_netif = eth_driver_init((QActive *)me, 0);
+
+ me->m_ip_addr = 0xFFFFFFFF; // initialize to impossible value
+
+ // initialize the lwIP applications...
+ httpd_init(); // initialize the simple HTTP-Deamon (web server)
+ http_set_ssi_handler(&ssi_handler, ssi_tags, Q_DIM(ssi_tags));
+ http_set_cgi_handlers(cgi_handlers, Q_DIM(cgi_handlers));
+
+ me->m_upcb = udp_new();
+ udp_bind(me->m_upcb, IP_ADDR_ANY, 777); // use port 777 for UDP
+ udp_recv(me->m_upcb, &udp_rx_handler, me);
+
+ QS_OBJ_DICTIONARY(&l_lwIPMgr);
+ QS_OBJ_DICTIONARY(&l_lwIPMgr.m_te_LWIP_SLOW_TICK);
+ QS_FUN_DICTIONARY(&QHsm::top);
+ QS_FUN_DICTIONARY(&LwIPMgr::initial);
+ QS_FUN_DICTIONARY(&LwIPMgr::running);
+
+ QS_SIG_DICTIONARY(SEND_UDP_SIG, me);
+ QS_SIG_DICTIONARY(LWIP_SLOW_TICK_SIG, me);
+ QS_SIG_DICTIONARY(LWIP_RX_READY_SIG, me);
+ QS_SIG_DICTIONARY(LWIP_TX_READY_SIG, me);
+ QS_SIG_DICTIONARY(LWIP_RX_OVERRUN_SIG, me);
+
+ return Q_TRAN(&LwIPMgr::running);
+}
+//............................................................................
+QState LwIPMgr::running(LwIPMgr *me, QEvent const *e) {
+ switch (e->sig) {
+ case Q_ENTRY_SIG: {
+ me->m_te_LWIP_SLOW_TICK.postEvery((QActive *)me,
+ (LWIP_SLOW_TICK_MS * BSP_TICKS_PER_SEC) / 1000);
+ return Q_HANDLED();
+ }
+ case Q_EXIT_SIG: {
+ me->m_te_LWIP_SLOW_TICK.disarm();
+ return Q_HANDLED();
+ }
+
+ case SEND_UDP_SIG: {
+ if (me->m_upcb->remote_port != (uint16_t)0) {
+ struct pbuf *p = pbuf_new((u8_t *)((TextEvt const *)e)->text,
+ strlen(((TextEvt const *)e)->text) + 1);
+ if (p != (struct pbuf *)0) {
+ udp_send(me->m_upcb, p);
+ pbuf_free(p); // don't leak the pbuf!
+
+ QS_BEGIN(LWIP_SEND_UDP, me) // app-specific record begin
+ QS_STR(((TextEvt const *)e)->text);
+ QS_END()
+ }
+ }
+ return Q_HANDLED();
+ }
+
+ case LWIP_RX_READY_SIG: {
+ eth_driver_read();
+ return Q_HANDLED();
+ }
+ case LWIP_TX_READY_SIG: {
+ eth_driver_write();
+ return Q_HANDLED();
+ }
+ case LWIP_SLOW_TICK_SIG: {
+ QS_BEGIN(LWIP_SLOW_TICK, me) // app-specific record begin
+ QS_END()
+
+ if (me->m_ip_addr != me->m_netif->ip_addr.addr) {
+ me->m_ip_addr = me->m_netif->ip_addr.addr; // save the IP addr
+ uint32_t ip_net = ntohl(me->m_ip_addr);// IP in network order
+ // publish the text event to display the new IP address
+ QS_BEGIN(LWIP_IPADDR, me) // app-specific record begin
+ QS_U8(3, (uint8_t)(ip_net >> 24));
+ QS_U8(3, (uint8_t)(ip_net >> 16));
+ QS_U8(3, (uint8_t)(ip_net >> 8));
+ QS_U8(3, (uint8_t)ip_net);
+ QS_END()
+ }
+
+#if LWIP_TCP
+ me->m_tcp_tmr += LWIP_SLOW_TICK_MS;
+ if (me->m_tcp_tmr >= TCP_TMR_INTERVAL) {
+ me->m_tcp_tmr = 0;
+ tcp_tmr();
+ }
+#endif
+#if LWIP_ARP
+ me->m_arp_tmr += LWIP_SLOW_TICK_MS;
+ if (me->m_arp_tmr >= ARP_TMR_INTERVAL) {
+ me->m_arp_tmr = 0;
+ etharp_tmr();
+ }
+#endif
+#if LWIP_DHCP
+ me->m_dhcp_fine_tmr += LWIP_SLOW_TICK_MS;
+ if (me->m_dhcp_fine_tmr >= DHCP_FINE_TIMER_MSECS) {
+ me->m_dhcp_fine_tmr = 0;
+ dhcp_fine_tmr();
+ }
+ me->m_dhcp_coarse_tmr += LWIP_SLOW_TICK_MS;
+ if (me->m_dhcp_coarse_tmr >= DHCP_COARSE_TIMER_MSECS) {
+ me->m_dhcp_coarse_tmr = 0;
+ dhcp_coarse_tmr();
+ }
+#endif
+#if LWIP_AUTOIP
+ me->auto_ip_tmr += LWIP_SLOW_TICK_MS;
+ if (me->auto_ip_tmr >= AUTOIP_TMR_INTERVAL) {
+ me->auto_ip_tmr = 0;
+ autoip_tmr();
+ }
+#endif
+ return Q_HANDLED();
+ }
+ case LWIP_RX_OVERRUN_SIG: {
+ LINK_STATS_INC(link.err);
+ return Q_HANDLED();
+ }
+ }
+ return Q_SUPER(&QHsm::top);
+}
+
+// HTTPD customizations ------------------------------------------------------
+
+// Server-Side Include (SSI) handler .........................................
+static int ssi_handler(int iIndex, char *pcInsert, int iInsertLen) {
+ struct stats_proto *stats = &lwip_stats.link;
+ STAT_COUNTER value;
+
+ switch (iIndex) {
+ case 0: // s_xmit
+ value = stats->xmit;
+ break;
+ case 1: // s_recv
+ value = stats->recv;
+ break;
+ case 2: // s_fw
+ value = stats->fw;
+ break;
+ case 3: // s_drop
+ value = stats->drop;
+ break;
+ case 4: // s_chkerr
+ value = stats->chkerr;
+ break;
+ case 5: // s_lenerr
+ value = stats->lenerr;
+ break;
+ case 6: // s_memerr
+ value = stats->memerr;
+ break;
+ case 7: // s_rterr
+ value = stats->rterr;
+ break;
+ case 8: // s_proerr
+ value = stats->proterr;
+ break;
+ case 9: // s_opterr
+ value = stats->opterr;
+ break;
+ case 10: // s_err
+ value = stats->err;
+ break;
+ }
+
+ return snprintf(pcInsert, MAX_TAG_INSERT_LEN, "%d", value);
+}
+
+// Common Gateway Iinterface (CG) handler ....................................
+static char const *cgi_display(int index, int numParams,
+ char const *param[],
+ char const *value[])
+{
+ for (int i = 0; i < numParams; ++i) {
+ if (strstr(param[i], "text") != (char *)0) { // param text found?
+
+
+ TextEvt *te = Q_NEW(TextEvt, DISPLAY_CGI_SIG);
+ strncpy(te->text, value[i], Q_DIM(te->text));
+ QF::publish((QEvent *)te);
+ return "/thank_you.htm";
+ }
+ }
+ return (char *)0; // no URI, HTTPD will send 404 error page to the browser
+}
+
+// UDP receive handler -------------------------------------------------------
+static void udp_rx_handler(void *arg, struct udp_pcb *upcb,
+ struct pbuf *p, struct ip_addr *addr, u16_t port)
+{
+ TextEvt *te = Q_NEW(TextEvt, DISPLAY_UDP_SIG);
+ strncpy(te->text, (char *)p->payload, Q_DIM(te->text));
+ QF::publish(te);
+
+ udp_connect(upcb, addr, port); // connect to the remote host
+ pbuf_free(p); // don't leak the pbuf!
+}