mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-27 19:53:32 +08:00
123 lines
3.2 KiB
C
123 lines
3.2 KiB
C
/* Convert `time_t' to `struct tm' in local time zone.
|
|
Copyright (C) 1991, 92, 93, 95, 96, 97 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., 59 Temple Place - Suite 330,
|
|
Boston, MA 02111-1307, 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;
|
|
|
|
/* Prototype for the internal function to get information based on TZ. */
|
|
extern void __tzset_internal __P ((int always));
|
|
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));
|
|
|
|
extern int __use_tzfile;
|
|
|
|
/* 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'. */
|
|
__libc_lock_define (extern, __tzset_lock)
|
|
|
|
|
|
/* Return the `struct tm' representation of *TIMER in the local timezone. */
|
|
static struct tm *
|
|
localtime_internal (const time_t *timer, struct tm *tp)
|
|
{
|
|
long int leap_correction;
|
|
int leap_extra_secs;
|
|
|
|
if (timer == NULL)
|
|
{
|
|
__set_errno (EINVAL);
|
|
return NULL;
|
|
}
|
|
|
|
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];
|
|
}
|
|
|
|
return tp;
|
|
}
|
|
|
|
|
|
/* POSIX.1 8.3.7.2 says that localtime_r is not required to set
|
|
tzname. This is a good idea since this allows at least a bit more
|
|
parallelism. */
|
|
|
|
struct tm *
|
|
localtime (timer)
|
|
const time_t *timer;
|
|
{
|
|
struct tm *result;
|
|
|
|
__libc_lock_lock (__tzset_lock);
|
|
|
|
/* Update internal database according to current TZ setting. */
|
|
__tzset_internal (1);
|
|
|
|
result = localtime_internal (timer, &_tmbuf);
|
|
|
|
__libc_lock_unlock (__tzset_lock);
|
|
|
|
return result;
|
|
}
|
|
|
|
|
|
struct tm *
|
|
__localtime_r (timer, tp)
|
|
const time_t *timer;
|
|
struct tm *tp;
|
|
{
|
|
struct tm *result;
|
|
|
|
__libc_lock_lock (__tzset_lock);
|
|
|
|
/* Make sure the database is initialized. */
|
|
__tzset_internal (0);
|
|
|
|
result = localtime_internal (timer, tp);
|
|
|
|
__libc_lock_unlock (__tzset_lock);
|
|
|
|
return result;
|
|
}
|
|
weak_alias (__localtime_r, localtime_r)
|