/* 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ #include #include #include /* 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 ((void)); 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); /* Make sure the database is initialized. */ __tzset_internal (); 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); result = localtime_internal (timer, tp); __libc_lock_unlock (__tzset_lock); return result; } weak_alias (__localtime_r, localtime_r)