glibc/time/localtime.c
1995-02-18 01:27:10 +00:00

85 lines
2.2 KiB
C

/* Copyright (C) 1991, 1992, 1993 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 <ansidecl.h>
#include <localeinfo.h>
#include <stddef.h>
#include <ctype.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#ifndef HAVE_GNU_LD
#define __tzname tzname
#define __daylight daylight
#define __timezone timezone
#endif
/* Return the `struct tm' representation of *TIMER in the local timezone. */
struct tm *
DEFUN(localtime, (timer), CONST time_t *timer)
{
extern int __use_tzfile;
extern int EXFUN(__tz_compute, (time_t timer, struct tm *tp));
extern int EXFUN(__tzfile_compute, (time_t timer,
long int *leap_correct, int *leap_hit));
register struct tm *tp;
long int leap_correction;
int leap_extra_secs;
if (timer == NULL)
{
errno = EINVAL;
return NULL;
}
{
/* Make sure the database is initialized. */
extern int __tzset_run;
if (! __tzset_run)
__tzset ();
}
if (__use_tzfile)
{
if (! __tzfile_compute (*timer, &leap_correction, &leap_extra_secs))
return NULL;
}
else
{
tp = gmtime (timer);
if (tp == NULL)
return NULL;
if (! __tz_compute (*timer, tp))
return NULL;
leap_correction = 0L;
leap_extra_secs = 0;
}
tp = __offtime (timer, __timezone - leap_correction);
tp->tm_sec += leap_extra_secs;
tp->tm_isdst = __daylight;
tp->tm_gmtoff = __timezone;
tp->tm_zone = __tzname[__daylight];
return tp;
}