sntp.c
2.8 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
/*
* Copyright (C) 2016 Luminița Lăzărescu <cluminita.lazarescu@gmail.com>
*
* This file is subject to the terms and conditions of the GNU Lesser
* General Public License v2.1. See the file LICENSE in the top level
* directory for more details.
*/
/**
* @{
*
* @file
* @brief SNTP implementation
*
* @author Luminița Lăzărescu <cluminita.lazarescu@gmail.com>
* @author Martine Lenders <m.lenders@fu-berlin.de>
*
* @}
*/
#include <string.h>
#include "net/sntp.h"
#include "net/ntp_packet.h"
#include "net/sock/udp.h"
#include "xtimer.h"
#include "mutex.h"
#include "byteorder.h"
#define ENABLE_DEBUG (1)
#include "debug.h"
static sock_udp_t _sntp_sock;
static int64_t _sntp_offset = 0;
static mutex_t _sntp_mutex = MUTEX_INIT;
static ntp_packet_t _sntp_packet;
int sntp_sync(sock_udp_ep_t *server, uint32_t timeout)
{
int result;
mutex_lock(&_sntp_mutex);
if ((result = sock_udp_create(&_sntp_sock,
NULL,
server,
0)) < 0) {
DEBUG("Error creating UDP sock\n");
mutex_unlock(&_sntp_mutex);
return result;
}
memset(&_sntp_packet, 0, sizeof(_sntp_packet));
ntp_packet_set_vn(&_sntp_packet);
ntp_packet_set_mode(&_sntp_packet, NTP_MODE_CLIENT);
_sntp_packet.transmit.seconds=byteorder_htonl( xtimer_now_usec());
if ((result = (int)sock_udp_send(&_sntp_sock,
&_sntp_packet,
sizeof(_sntp_packet),
NULL)) < 0) {
DEBUG("Error sending message\n");
sock_udp_close(&_sntp_sock);
mutex_unlock(&_sntp_mutex);
return result;
}
if ((result = (int)sock_udp_recv(&_sntp_sock,
&_sntp_packet,
sizeof(_sntp_packet),
timeout,
NULL)) < 0) {
DEBUG("Error receiving message\n");
sock_udp_close(&_sntp_sock);
mutex_unlock(&_sntp_mutex);
return result;
}
//xtimer_ticks64_t now = xtimer_now64();
sock_udp_close(&_sntp_sock);
_sntp_offset= (byteorder_ntohl(_sntp_packet.receive.seconds)+ byteorder_ntohl(_sntp_packet.transmit.seconds))/2 - (byteorder_ntohl(_sntp_packet.origin.seconds) + xtimer_now_usec())/2;
/* _sntp_offset = (byteorder_ntohl(_sntp_packet.transmit.seconds) * SEC_IN_USEC) +
((byteorder_ntohl(_sntp_packet.transmit.fraction) * 232)
/ 1000000) - xtimer_now_usec();*/
mutex_unlock(&_sntp_mutex);
return 0;
}
int64_t sntp_get_offset(void)
{
int64_t result;
mutex_lock(&_sntp_mutex);
result = _sntp_offset;
mutex_unlock(&_sntp_mutex);
return result;
}