NTPClient.h

00001 /* NTPClient.h */
00002 /* Copyright (C) 2012 mbed.org, MIT License
00003  *
00004  * Permission is hereby granted, free of charge, to any person obtaining a copy of this software
00005  * and associated documentation files (the "Software"), to deal in the Software without restriction,
00006  * including without limitation the rights to use, copy, modify, merge, publish, distribute,
00007  * sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
00008  * furnished to do so, subject to the following conditions:
00009  *
00010  * The above copyright notice and this permission notice shall be included in all copies or
00011  * substantial portions of the Software.
00012  *
00013  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING
00014  * BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
00015  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
00016  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
00017  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
00018  */
00019 
00020 /** \file
00021 NTP Client header file
00022 */
00023 
00024 #ifndef NTPCLIENT_H_
00025 #define NTPCLIENT_H_
00026 
00027 #include <stdint.h>
00028 
00029 //using std::uint8_t;
00030 //using std::uint16_t;
00031 //using std::uint32_t;
00032 
00033 #include "UDPSocket.h"
00034 #include "NetworkInterface.h"
00035 
00036 #define NTP_DEFAULT_PORT 123
00037 #define NTP_DEFAULT_TIMEOUT 4000
00038 
00039 ///NTP client results
00040 enum NTPResult
00041 {
00042   NTP_DNS, ///<Could not resolve name
00043   NTP_PRTCL, ///<Protocol error
00044   NTP_TIMEOUT, ///<Connection timeout
00045   NTP_CONN, ///<Connection error
00046   NTP_OK = 0, ///<Success
00047 };
00048 
00049 /** NTP Client to update the mbed's RTC using a remote time server
00050 *
00051 */
00052 class NTPClient
00053 {
00054 public:
00055   /**
00056   Instantiate the NTP client
00057   */
00058  // NTPClient();
00059   NTPClient(NetworkInterface & _m_intf);
00060   /**Get current time (blocking)
00061   Update the time using the server host
00062   Blocks until completion
00063   @param host NTP server IPv4 address or hostname (will be resolved via DNS)
00064   @param port port to use; defaults to 123
00065   @param timeout waiting timeout in ms (osWaitForever for blocking function, not recommended)
00066   @return 0 on success, NTP error code (<0) on failure
00067   */
00068   NTPResult setTime(const char* host, uint16_t port = NTP_DEFAULT_PORT, uint32_t timeout = NTP_DEFAULT_TIMEOUT); 
00069 
00070 private:
00071   struct NTPPacket //See RFC 4330 for Simple NTP
00072   {
00073     //WARN: We are in LE! Network is BE!
00074     //LSb first
00075     unsigned mode : 3;
00076     unsigned vn : 3;
00077     unsigned li : 2;
00078 
00079     uint8_t stratum;
00080     uint8_t poll;
00081     uint8_t precision;
00082     //32 bits header
00083 
00084     uint32_t rootDelay;
00085     uint32_t rootDispersion;
00086     uint32_t refId;
00087 
00088     uint32_t refTm_s;
00089     uint32_t refTm_f;
00090     uint32_t origTm_s;
00091     uint32_t origTm_f;
00092     uint32_t rxTm_s;
00093     uint32_t rxTm_f;
00094     uint32_t txTm_s;
00095     uint32_t txTm_f;
00096   } __attribute__ ((packed));
00097   
00098   NetworkInterface & m_intf;  // WiFi interface  
00099   UDPSocket m_sock;
00100 };
00101 
00102 
00103 #endif /* NTPCLIENT_H_ */