citadel/server/genstamp.c

   1 // This program is open source software.  Use, duplication, or disclosure
   2 // is subject to the terms of the GNU General Public License, version 3.
   3
   4
   5 // Function to generate RFC822-compliant textual time/date stamp
   6
   7 #include "sysdep.h"
   8 #include <stdio.h>
   9 #include <stdlib.h>
  10 #include <ctype.h>
  11 #include <string.h>
  12 #include <time.h>
  13 #include "genstamp.h"
  14
  15 static char *months[] = {
  16         "Jan", "Feb", "Mar", "Apr", "May", "Jun",
  17         "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
  18 };
  19
  20 static char *weekdays[] = {
  21         "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"
  22 };
  23
  24 // Supplied with a unix timestamp, generate an RFC822-compliant textual
  25 // time and date stamp.
  26 long datestring(char *buf, size_t n, time_t xtime, int which_format) {
  27         struct tm t;
  28
  29         long offset;
  30         char offsign;
  31
  32         localtime_r(&xtime, &t);
  33
  34         // Convert "seconds west of GMT" to "hours/minutes offset"
  35 #ifdef HAVE_STRUCT_TM_TM_GMTOFF
  36         offset = t.tm_gmtoff;
  37 #else
  38         offset = timezone;
  39 #endif
  40         if (offset > 0) {
  41                 offsign = '+';
  42         }
  43         else {
  44                 offset = 0L - offset;
  45                 offsign = '-';
  46         }
  47         offset = ( (offset / 3600) * 100 ) + ( offset % 60 );
  48
  49         switch(which_format) {
  50
  51                 case DATESTRING_RFC822:
  52                         return snprintf(
  53                                 buf, n,
  54                                 "%s, %02d %s %04d %02d:%02d:%02d %c%04ld",
  55                                 weekdays[t.tm_wday],
  56                                 t.tm_mday,
  57                                 months[t.tm_mon],
  58                                 t.tm_year + 1900,
  59                                 t.tm_hour,
  60                                 t.tm_min,
  61                                 t.tm_sec,
  62                                 offsign, offset
  63                                 );
  64                 break;
  65
  66                 case DATESTRING_IMAP:
  67                         return snprintf(
  68                                 buf, n,
  69                                 "%02d-%s-%04d %02d:%02d:%02d %c%04ld",
  70                                 t.tm_mday,
  71                                 months[t.tm_mon],
  72                                 t.tm_year + 1900,
  73                                 t.tm_hour,
  74                                 t.tm_min,
  75                                 t.tm_sec,
  76                                 offsign, offset
  77                                 );
  78                 break;
  79
  80         }
  81         return 0;
  82 }