lib/gztime.c

   1 /* gztime.c     convert into GeneralizedTime
   2  * Copyright (C) 2002, 2003  Simon Josefsson
   3  *
   4  * This file is part of Shishi.
   5  *
   6  * Shishi is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * Shishi is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with Shishi; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  *
  20  */
  21
  22 #include "internal.h"
  23
  24 const char *
  25 shishi_generalize_time (Shishi * handle, time_t t)
  26 {
  27   struct tm *tm;
  28
  29   tm = gmtime (&t);
  30   strftime (handle->gztime_buf, sizeof (handle->gztime_buf),
  31             "%Y%m%d%H%M%SZ", tm);
  32
  33   return handle->gztime_buf;
  34 }
  35
  36 static time_t
  37 my_timegm (struct tm *tm)
  38 {
  39   time_t ret;
  40   char *tz;
  41
  42   tz = getenv ("TZ");
  43   setenv ("TZ", "UTC", 1);
  44   tzset ();
  45   ret = mktime (tm);
  46   if (tz)
  47     setenv ("TZ", tz, 1);
  48   else
  49     unsetenv ("TZ");
  50   tzset ();
  51   return ret;
  52 }
  53
  54 time_t
  55 shishi_generalize_ctime (Shishi * handle, const char *t)
  56 {
  57   struct tm tm;
  58   time_t ct;
  59
  60   memset (&tm, 0, sizeof (tm));
  61
  62   sscanf (t, "%4u%2u%2u%2u%2u%2uZ",
  63           &tm.tm_year, &tm.tm_mon, &tm.tm_mday,
  64           &tm.tm_hour, &tm.tm_min, &tm.tm_sec);
  65   tm.tm_year -= 1900;
  66   tm.tm_mon--;
  67
  68   ct = my_timegm (&tm);
  69
  70   return ct;
  71 }