xapian-applications/omega/timegm.cc

   1 /** @file timegm.cc
   2  * @brief Portable implementation of timegm().
   3  */
   4 /* Copyright (c) 2013 Olly Betts
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a copy
   7  * of this software and associated documentation files (the "Software"), to
   8  * deal in the Software without restriction, including without limitation the
   9  * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
  10  * sell copies of the Software, and to permit persons to whom the Software is
  11  * furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included in
  14  * all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  19  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  21  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
  22  * IN THE SOFTWARE.
  23  */
  24
  25 #include <config.h>
  26 #include "timegm.h"
  27
  28 #ifndef HAVE_TIMEGM
  29
  30 #include <stdlib.h> // For setenv() or putenv()
  31 #include <time.h>
  32
  33 using namespace std;
  34
  35 time_t
  36 timegm(struct tm *tm)
  37 {
  38     static bool set_tz = false;
  39     if (!set_tz) {
  40 #ifdef HAVE__PUTENV_S
  41         _putenv_s("TZ", "");
  42 #elif defined HAVE_SETENV
  43         setenv("TZ", "", 1);
  44 #else
  45         putenv(const_cast<char*>("TZ="));
  46 #endif
  47         tzset();
  48         set_tz = true;
  49     }
  50     return mktime(tm);
  51 }
  52
  53 #endif