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/**
* @file
* SNTP client module
*
*/
/*
* 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/sys.h"
#include "lwip/sockets.h"
#include <string.h>
#include <time.h>
/** This is an example of a "SNTP" client (with socket API).
*
* For a list of some public NTP servers, see this link :
* http://support.ntp.org/bin/view/Servers/NTPPoolServers
*
*/
/**
* SNTP_DEBUG: Enable debugging for SNTP.
*/
#ifndef SNTP_DEBUG
#define SNTP_DEBUG LWIP_DBG_ON
#endif
/** SNTP server port */
#ifndef SNTP_PORT
#define SNTP_PORT 123
#endif
/** SNTP server address as IPv4 address in "u32_t" format */
#ifndef SNTP_SERVER_ADDRESS
#define SNTP_SERVER_ADDRESS inet_addr("213.161.194.93") /* pool.ntp.org */
#endif
/** SNTP receive timeout - in milliseconds */
#ifndef SNTP_RECV_TIMEOUT
#define SNTP_RECV_TIMEOUT 3000
#endif
/** SNTP update delay - in milliseconds */
#ifndef SNTP_UPDATE_DELAY
#define SNTP_UPDATE_DELAY 60000
#endif
/** SNTP macro to change system time and/or the update the RTC clock */
#ifndef SNTP_SYSTEM_TIME
#define SNTP_SYSTEM_TIME(t)
#endif
/* SNTP protocol defines */
#define SNTP_MAX_DATA_LEN 48
#define SNTP_RCV_TIME_OFS 32
#define SNTP_LI_NO_WARNING 0x00
#define SNTP_VERSION (4/* NTP Version 4*/<<3)
#define SNTP_MODE_CLIENT 0x03
#define SNTP_MODE_SERVER 0x04
#define SNTP_MODE_BROADCAST 0x05
#define SNTP_MODE_MASK 0x07
/* number of seconds between 1900 and 1970 */
#define DIFF_SEC_1900_1970 (2208988800)
/**
* SNTP processing
*/
static void sntp_process( time_t t)
{
/* change system time and/or the update the RTC clock */
SNTP_SYSTEM_TIME(t);
/* display local time from GMT time */
LWIP_DEBUGF( SNTP_DEBUG, ("sntp_process: %s", ctime(&t)));
}
/**
* SNTP request
*/
static void sntp_request()
{
int sock;
struct sockaddr_in local;
struct sockaddr_in to;
int tolen;
int size;
int timeout;
u8_t sntp_request [SNTP_MAX_DATA_LEN];
u8_t sntp_response[SNTP_MAX_DATA_LEN];
u32_t sntp_server_address;
u32_t timestamp;
time_t t;
/* initialize SNTP server address */
sntp_server_address = SNTP_SERVER_ADDRESS;
/* if we got a valid SNTP server address... */
if (sntp_server_address!=0)
{
/* create new socket */
sock = socket( AF_INET, SOCK_DGRAM, 0);
if (sock>=0)
{
/* prepare local address */
memset(&local, 0, sizeof(local));
local.sin_family = AF_INET;
local.sin_port = htons(INADDR_ANY);
local.sin_addr.s_addr = htonl(INADDR_ANY);
/* bind to local address */
if (bind( sock, (struct sockaddr *)&local, sizeof(local))==0)
{
/* set recv timeout */
timeout = SNTP_RECV_TIMEOUT;
setsockopt( sock, SOL_SOCKET, SO_RCVTIMEO, (char *)&timeout, sizeof(timeout));
/* prepare SNTP request */
memset( sntp_request, 0, sizeof(sntp_request));
sntp_request[0] = SNTP_LI_NO_WARNING | SNTP_VERSION | SNTP_MODE_CLIENT;
/* prepare SNTP server address */
memset(&to, 0, sizeof(to));
to.sin_family = AF_INET;
to.sin_port = htons(SNTP_PORT);
to.sin_addr.s_addr = sntp_server_address;
/* send SNTP request to server */
if (sendto( sock, sntp_request, sizeof(sntp_request), 0, (struct sockaddr *)&to, sizeof(to))>=0)
{
/* receive SNTP server response */
tolen = sizeof(to);
size = recvfrom( sock, sntp_response, sizeof(sntp_response), 0, (struct sockaddr *)&to, (socklen_t *)&tolen);
/* if the response size is good */
if (size == SNTP_MAX_DATA_LEN)
{
/* if this is a SNTP response... */
if (((sntp_response[0] & SNTP_MODE_MASK) == SNTP_MODE_SERVER) || ((sntp_response[0] & SNTP_MODE_MASK) == SNTP_MODE_BROADCAST))
{
/* extract GMT time from response */
SMEMCPY( ×tamp, (sntp_response+SNTP_RCV_TIME_OFS), sizeof(timestamp));
t = (ntohl(timestamp) - DIFF_SEC_1900_1970);
/* do time processing */
sntp_process(t);
}
else
{
LWIP_DEBUGF( SNTP_DEBUG, ("sntp_request: not response frame code\n"));
}
}
else
{
LWIP_DEBUGF( SNTP_DEBUG, ("sntp_request: not recvfrom==%i\n", errno));
}
}
else
{
LWIP_DEBUGF( SNTP_DEBUG, ("sntp_request: not sendto==%i\n", errno));
}
}
/* close the socket */
closesocket(sock);
}
}
}
/**
* SNTP thread
*/
static void
sntp_thread(void *arg)
{
LWIP_UNUSED_ARG(arg);
while(1)
{
sntp_request();
sys_msleep(SNTP_UPDATE_DELAY);
}
}
void sntp_init(void)
{
sys_thread_new("sntp_thread", sntp_thread, NULL, DEFAULT_THREAD_STACKSIZE, DEFAULT_THREAD_PRIO);
}
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