Merge branch 'master' of ssh://sourceware.org/git/glibc
[glibc.git] / time / timegm.c
blobbbc8c919add0559f82fe41b3e05040e02bc60ee9
1 /* Convert UTC calendar time to simple time. Like mktime but assumes UTC.
3 Copyright (C) 1994, 1997, 2003 Free Software Foundation, Inc.
4 This file is part of the GNU C Library.
6 The GNU C Library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Lesser General Public
8 License as published by the Free Software Foundation; either
9 version 2.1 of the License, or (at your option) any later version.
11 The GNU C Library is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details.
16 You should have received a copy of the GNU Lesser General Public
17 License along with the GNU C Library; if not, write to the Free
18 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
19 02111-1307 USA. */
21 #ifdef HAVE_CONFIG_H
22 # include <config.h>
23 #endif
25 #ifdef _LIBC
26 # include <time.h>
27 #else
28 # include "timegm.h"
30 /* Portable standalone applications should supply a "time_r.h" that
31 declares a POSIX-compliant gmtime_r, for the benefit of older
32 implementations that lack gmtime_r or have a nonstandard one.
33 See the gnulib time_r module for one way to implement this. */
34 # include <time_r.h>
35 # undef __gmtime_r
36 # define __gmtime_r gmtime_r
37 time_t __mktime_internal (struct tm *,
38 struct tm * (*) (time_t const *, struct tm *),
39 time_t *);
40 #endif
42 time_t
43 timegm (struct tm *tmp)
45 static time_t gmtime_offset;
46 tmp->tm_isdst = 0;
47 return __mktime_internal (tmp, __gmtime_r, &gmtime_offset);