gl/time_r.c

   1 /* Reentrant time functions like localtime_r.
   2
   3    Copyright (C) 2003 Free Software Foundation, Inc.
   4
   5    This program is free software; you can redistribute it and/or modify
   6    it under the terms of the GNU General Public License as published by
   7    the Free Software Foundation; either version 2, or (at your option)
   8    any later version.
   9
  10    This program is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13    GNU General Public License for more details.
  14
  15    You should have received a copy of the GNU General Public License along
  16    with this program; if not, write to the Free Software Foundation,
  17    Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  18
  19 /* Written by Paul Eggert.  */
  20
  21 #if HAVE_CONFIG_H
  22 # include <config.h>
  23 #endif
  24
  25 #include "time_r.h"
  26
  27 #include <string.h>
  28
  29 static char *
  30 copy_string_result (char *dest, char const *src)
  31 {
  32   if (! src)
  33     return 0;
  34   return strcpy (dest, src);
  35 }
  36
  37 static struct tm *
  38 copy_tm_result (struct tm *dest, struct tm const *src)
  39 {
  40   if (! src)
  41     return 0;
  42   *dest = *src;
  43   return dest;
  44 }
  45
  46
  47 char *
  48 asctime_r (struct tm const * restrict tm, char * restrict buf)
  49 {
  50   return copy_string_result (buf, asctime (tm));
  51 }
  52
  53 char *
  54 ctime_r (time_t const *t, char *buf)
  55 {
  56   return copy_string_result (buf, ctime (t));
  57 }
  58
  59 struct tm *
  60 gmtime_r (time_t const * restrict t, struct tm * restrict tp)
  61 {
  62   return copy_tm_result (tp, gmtime (t));
  63 }
  64
  65 struct tm *
  66 localtime_r (time_t const * restrict t, struct tm * restrict tp)
  67 {
  68   return copy_tm_result (tp, localtime (t));
  69 }