summaryrefslogtreecommitdiffstats
path: root/refclock_sock.c
blob: 86143cf46423eebc672fadddb7c602e400a05d79 (plain)
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
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
/*
  chronyd/chronyc - Programs for keeping computer clocks accurate.

 **********************************************************************
 * Copyright (C) Miroslav Lichvar  2009
 * 
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of version 2 of the GNU General Public License as
 * published by the Free Software Foundation.
 * 
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 * 
 **********************************************************************

  =======================================================================

  Unix domain socket refclock driver.

  */

#include "config.h"

#include "sysincl.h"

#include "refclock.h"
#include "logging.h"
#include "util.h"
#include "sched.h"
#include "socket.h"

#define SOCK_MAGIC 0x534f434b

struct sock_sample {
  /* Time of the measurement (system time) */
  struct timeval tv;

  /* Offset between the true time and the system time (in seconds) */
  double offset;

  /* Non-zero if the sample is from a PPS signal, i.e. another source
     is needed to obtain seconds */
  int pulse;

  /* 0 - normal, 1 - insert leap second, 2 - delete leap second */
  int leap;

  /* Padding, ignored */
  int _pad;

  /* Protocol identifier (0x534f434b) */
  int magic;
};

static void read_sample(int sockfd, int event, void *anything)
{
  struct sock_sample sample;
  struct timespec ts;
  RCL_Instance instance;
  int s;

  instance = (RCL_Instance)anything;

  s = recv(sockfd, &sample, sizeof (sample), 0);

  if (s < 0) {
    DEBUG_LOG("Could not read SOCK sample : %s", strerror(errno));
    return;
  }

  if (s != sizeof (sample)) {
    DEBUG_LOG("Unexpected length of SOCK sample : %d != %ld",
              s, (long)sizeof (sample));
    return;
  }

  if (sample.magic != SOCK_MAGIC) {
    DEBUG_LOG("Unexpected magic number in SOCK sample : %x != %x",
              (unsigned int)sample.magic, (unsigned int)SOCK_MAGIC);
    return;
  }

  UTI_TimevalToTimespec(&sample.tv, &ts);
  UTI_NormaliseTimespec(&ts);

  if (sample.pulse) {
    RCL_AddPulse(instance, &ts, sample.offset);
  } else {
    RCL_AddSample(instance, &ts, sample.offset, sample.leap);
  }
}

static int sock_initialise(RCL_Instance instance)
{
  int sockfd;
  char *path;

  RCL_CheckDriverOptions(instance, NULL);

  path = RCL_GetDriverParameter(instance);
 
  sockfd = SCK_OpenUnixDatagramSocket(NULL, path, 0);
  if (sockfd < 0)
    LOG_FATAL("Could not open socket %s", path);

  RCL_SetDriverData(instance, (void *)(long)sockfd);
  SCH_AddFileHandler(sockfd, SCH_FILE_INPUT, read_sample, instance);
  return 1;
}

static void sock_finalise(RCL_Instance instance)
{
  int sockfd;

  sockfd = (long)RCL_GetDriverData(instance);
  SCH_RemoveFileHandler(sockfd);
  SCK_RemoveSocket(sockfd);
  SCK_CloseSocket(sockfd);
}

RefclockDriver RCL_SOCK_driver = {
  sock_initialise,
  sock_finalise,
  NULL
};