glibc/sysdeps/posix/gettimeofday.c

68 lines
1.9 KiB
C

/* Copyright (C) 1991-2016 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 Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#include <errno.h>
#include <time.h>
#include <sys/time.h>
/* 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 (struct timeval *tv, struct timezone *tz)
{
if (tv == NULL)
{
__set_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;
}
libc_hidden_def (__gettimeofday)
weak_alias (__gettimeofday, gettimeofday)
libc_hidden_weak (gettimeofday)