NTPClient.h

00001 
00002 /*
00003 Copyright (c) 2010 Donatien Garnier (donatiengar [at] gmail [dot] com)
00004  
00005 Permission is hereby granted, free of charge, to any person obtaining a copy
00006 of this software and associated documentation files (the "Software"), to deal
00007 in the Software without restriction, including without limitation the rights
00008 to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
00009 copies of the Software, and to permit persons to whom the Software is
00010 furnished to do so, subject to the following conditions:
00011  
00012 The above copyright notice and this permission notice shall be included in
00013 all copies or substantial portions of the Software.
00014  
00015 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
00016 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
00017 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
00018 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
00019 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
00020 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
00021 THE SOFTWARE.
00022 */
00023 
00024 #ifndef NTP_CLIENT_H
00025 #define NTP_CLIENT_H
00026 
00027 #include "if/net/net.h"
00028 #include "api/UDPSocket.h"
00029 #include "api/DNSRequest.h"
00030 #include "mbed.h"
00031 
00032 enum NTPResult
00033 {
00034   NTP_OK,
00035   NTP_PROCESSING,
00036   NTP_PRTCL, //Protocol error
00037   NTP_TIMEOUT, //Connection timeout
00038   NTP_DNS //Could not resolve DNS Addr
00039 };
00040 
00041 class NTPClient
00042 {
00043 public:
00044   NTPClient();
00045   virtual ~NTPClient();
00046   
00047   //High level setup functions
00048   NTPResult setTime(const Host& host); //Blocking
00049   NTPResult setTime(const Host& host, void (*pMethod)(NTPResult)); //Non blocking
00050   template<class T> 
00051   NTPResult setTime(const Host& host, T* pItem, void (T::*pMethod)(NTPResult)) //Non blocking
00052   {
00053     setOnResult(pItem, pMethod);
00054     doSetTime(host);
00055     return NTP_PROCESSING;
00056   }
00057   
00058   void doSetTime(const Host& host);
00059   
00060   void setOnResult( void (*pMethod)(NTPResult) );
00061   class CDummy;
00062   template<class T> 
00063   void setOnResult( T* pItem, void (T::*pMethod)(NTPResult) )
00064   {
00065     m_pCbItem = (CDummy*) pItem;
00066     m_pCbMeth = (void (CDummy::*)(NTPResult)) pMethod;
00067   }
00068   
00069   void init();
00070   void close();
00071   
00072 private:
00073   __packed struct NTPPacket //See RFC 4330 for Simple NTP
00074   {
00075     //WARN: We are in LE! Network is BE!
00076     //LSb first
00077     unsigned mode : 3;
00078     unsigned vn : 3;
00079     unsigned li : 2;
00080     
00081     uint8_t stratum;
00082     uint8_t poll;
00083     uint8_t precision;
00084     //32 bits header
00085     
00086     uint32_t rootDelay;
00087     uint32_t rootDispersion;
00088     uint32_t refId;
00089     
00090     uint32_t refTm_s;
00091     uint32_t refTm_f;
00092     uint32_t origTm_s;
00093     uint32_t origTm_f;
00094     uint32_t rxTm_s;
00095     uint32_t rxTm_f;
00096     uint32_t txTm_s;
00097     uint32_t txTm_f;
00098   };
00099 
00100   void process(); //Main state-machine
00101 
00102   void setTimeout(int ms);
00103   void resetTimeout();
00104   
00105   void onTimeout(); //Connection has timed out
00106   void onDNSReply(DNSReply r);
00107   void onUDPSocketEvent(UDPSocketEvent e);
00108   void onResult(NTPResult r); //Called when exchange completed or on failure
00109   
00110   NTPResult blockingProcess(); //Called in blocking mode, calls Net::poll() until return code is available
00111 
00112   UDPSocket* m_pUDPSocket;
00113 
00114   enum NTPStep
00115   {
00116     NTP_PING,
00117     NTP_PONG
00118   };
00119   
00120   NTPStep m_state;
00121   
00122   CDummy* m_pCbItem;
00123   void (CDummy::*m_pCbMeth)(NTPResult);
00124   
00125   void (*m_pCb)(NTPResult);
00126   
00127   Timeout m_watchdog;
00128   int m_timeout;
00129   
00130   bool m_closed;
00131   
00132   Host m_host;
00133   
00134   DNSRequest* m_pDnsReq;
00135   
00136   NTPResult m_blockingResult; //Result if blocking mode
00137 
00138 };
00139 
00140 #endif