/* localtime -- convert `time_t' to `struct tm' in local time zone
Copyright (C) 1991, 92, 93, 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 <libc-lock.h>
/* The C Standard says that localtime and gmtime return the same pointer. */
struct tm _tmbuf;
/* Return the `struct tm' representation of *TIMER in the local timezone. */
struct tm *
localtime (timer)
const time_t *timer;
{
return __localtime_r (timer, &_tmbuf);
}
struct tm *
__localtime_r (timer, tp)
const time_t *timer;
struct tm *tp;
{
/* This lock is defined in tzset.c and locks all the data defined there
and in tzfile.c; the internal functions do no locking themselves.
This lock is only taken here and in `tzset'. */
extern int __tzset_run, __use_tzfile;
extern int __tz_compute __P ((time_t timer, struct tm *tp));
extern int __tzfile_compute __P ((time_t timer,
long int *leap_correct, int *leap_hit));
long int leap_correction;
int leap_extra_secs;
__libc_lock_define (extern, __tzset_lock);
if (timer == NULL)
{
errno = EINVAL;
return NULL;
}
__libc_lock_lock (__tzset_lock);
/* Make sure the database is initialized. */
if (! __tzset_run)
__tzset ();
if (__use_tzfile)
{
if (! __tzfile_compute (*timer, &leap_correction, &leap_extra_secs))
tp = NULL;
}
else
{
tp = __gmtime_r (timer, tp);
if (tp && ! __tz_compute (*timer, tp))
tp = NULL;
leap_correction = 0L;
leap_extra_secs = 0;
}
if (tp)
{
__offtime (timer, __timezone - leap_correction, tp);
tp->tm_sec += leap_extra_secs;
tp->tm_isdst = __daylight;
tp->tm_gmtoff = __timezone;
tp->tm_zone = __tzname[__daylight];
}
__libc_lock_unlock (__tzset_lock);
return tp;
}
weak_alias (__localtime_r, localtime_r)