1                 : /* -*- mode: C -*-
       2                 :  *
       3                 :  *       File:         pdf-time-context.c
       4                 :  *       Date:         Sun May 18 13:08:37 2008
       5                 :  *
       6                 :  *       GNU PDF Library - Time Module Context management
       7                 :  *
       8                 :  */
       9                 : 
      10                 : /* Copyright (C) 2008 Free Software Foundation, Inc. */
      11                 : 
      12                 : /* This program is free software: you can redistribute it and/or modify
      13                 :  * it under the terms of the GNU General Public License as published by
      14                 :  * the Free Software Foundation, either version 3 of the License, or
      15                 :  * (at your option) any later version.
      16                 :  *
      17                 :  * This program is distributed in the hope that it will be useful,
      18                 :  * but WITHOUT ANY WARRANTY; without even the implied warranty of
      19                 :  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
      20                 :  * GNU General Public License for more details.
      21                 :  *
      22                 :  * You should have received a copy of the GNU General Public License
      23                 :  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
      24                 :  */
      25                 : 
      26                 : #include <config.h>
      27                 : 
      28                 : #include <stdio.h>
      29                 : #include <time.h>
      30                 : 
      31                 : #include <pdf-alloc.h>
      32                 : #include <pdf-time-context.h>
      33                 : 
      34                 : 
      35                 : typedef struct pdf_time_context_s {
      36                 :   pdf_i32_t   local_time_gmt_offset;      /* Seconds west of GMT */
      37                 :   pdf_bool_t  local_time_daylight_save; /* True if Daylight saving times */
      38                 : } pdf_time_context_t;
      39                 : 
      40                 : 
      41                 : /* This context will be initialized only once at program startup, and it will
      42                 :  *  be treated as constant from then on, so there shouldn't be any problem
      43                 :  *  with multiple threading and reentrancy */
      44                 : static pdf_time_context_t time_context;
      45                 : 
      46                 : 
      47                 : 
      48                 : /* Initialize time context. Must be done only once at program startup!.
      49                 :  *  Not thread-safe! */
      50                 : pdf_status_t
      51                 : pdf_time_context_init(void)
      52             618 : {
      53                 :   time_t tloc;
      54                 :   struct tm* time_struct;
      55                 : 
      56             618 :   time(&tloc);
      57             618 :   time_struct = localtime(&tloc);
      58                 : 
      59                 : #if defined PDF_HOST_WIN32
      60                 :   /* mingw does not support tm_gmtoff in struct tm, but it provides
      61                 :      the _timezone global variable with the difference in seconds
      62                 :      between GMT and local time. */
      63                 :   time_context.local_time_gmt_offset = _timezone;
      64                 : #else
      65                 :   /* Set GMT offset */
      66             618 :   time_context.local_time_gmt_offset = time_struct->tm_gmtoff;
      67                 : #endif
      68                 : 
      69                 :   /* Set flag to indicate if Daylight saving times are applied in the system
      70                 :    * if needed */
      71             618 :   time_context.local_time_daylight_save = (time_struct->tm_isdst == 0) ? PDF_FALSE : PDF_TRUE;
      72                 :   
      73                 :   PDF_DEBUG_BASE("Initializing Time module...");
      74                 :   PDF_DEBUG_BASE("GMT offset: %d secs", time_context.local_time_gmt_offset);
      75                 :   PDF_DEBUG_BASE("Daylight saving? %s",time_context.local_time_daylight_save ? \
      76                 :                  "yes":"no");
      77                 : 
      78             618 :   return PDF_OK;
      79                 : }
      80                 : 
      81                 : 
      82                 : /* Get the GMT offset of the local time configuration. The offset is obtained as
      83                 :  *  seconds west of GMT */
      84                 : pdf_i32_t
      85                 : pdf_time_context_get_gmt_offset(void)
      86              76 : {
      87              76 :   return time_context.local_time_gmt_offset;
      88                 : }
      89                 : 
      90                 : 
      91                 : /* End of pdf-time-context.c */