summaryrefslogtreecommitdiff
path: root/sysdeps/posix/gettimeofday.c
blob: 3c079a5af210582ff67ddcea5ebaf7a6a2872f33 (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
/* Copyright (C) 1991, 92, 94, 95, 96 Free Software Foundation, Inc.
This file is part of the GNU C Library.

The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.

The GNU C Library 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
Library General Public License for more details.

You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB.  If
not, write to the Free Software Foundation, Inc., 675 Mass Ave,
Cambridge, MA 02139, USA.  */

#include <errno.h>
#include <time.h>
#include <sys/time.h>

#ifndef HAVE_GNU_LD
#define __daylight	daylight
#define __timezone	timezone
#define __tzname	tzname
#endif


/* Get the current time of day and timezone information,
   putting it into *TV and *TZ.  If TZ is NULL, *TZ is not filled.
   Returns 0 on success, -1 on errors.  */
int
__gettimeofday (tv, tz)
     struct timeval *tv;
     struct timezone *tz;
{
  if (tv == NULL)
    {
      errno = EINVAL;
      return -1;
    }

  tv->tv_sec = (long int) time ((time_t *) NULL);
  tv->tv_usec = 0L;

  if (tz != NULL)
    {
      const time_t timer = tv->tv_sec;
      struct tm tm;
      const struct tm *tmp;

      const long int save_timezone = __timezone;
      const long int save_daylight = __daylight;
      char *save_tzname[2];
      save_tzname[0] = __tzname[0];
      save_tzname[1] = __tzname[1];

      tmp = localtime_r (&timer, &tm);

      tz->tz_minuteswest = __timezone / 60;
      tz->tz_dsttime = __daylight;

      __timezone = save_timezone;
      __daylight = save_daylight;
      __tzname[0] = save_tzname[0];
      __tzname[1] = save_tzname[1];

      if (tmp == NULL)
	return -1;
    }

  return 0;
}

weak_alias (__gettimeofday, gettimeofday)