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 // The program is distributed without any warranty, expressed or implied.
   4
   5
   6 /*
   7  * Function to generate RFC822-compliant textual time/date stamp
   8  */
   9
  10 #include "sysdep.h"
  11 #include <stdio.h>
  12 #include <stdlib.h>
  13 #include <ctype.h>
  14 #include <string.h>
  15 #include <time.h>
  16 #include "genstamp.h"
  17
  18 static char *months[] = {
  19         "Jan", "Feb", "Mar", "Apr", "May", "Jun",
  20         "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
  21 };
  22
  23 static char *weekdays[] = {
  24         "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"
  25 };
  26
  27 /*
  28  * Supplied with a unix timestamp, generate an RFC822-compliant textual
  29  * time and date stamp.
  30  */
  31 long datestring(char *buf, size_t n, time_t xtime, int which_format) {
  32         struct tm t;
  33
  34         long offset;
  35         char offsign;
  36
  37         localtime_r(&xtime, &t);
  38
  39         /* Convert "seconds west of GMT" to "hours/minutes offset" */
  40 #ifdef HAVE_STRUCT_TM_TM_GMTOFF
  41         offset = t.tm_gmtoff;
  42 #else
  43         offset = timezone;
  44 #endif
  45         if (offset > 0) {
  46                 offsign = '+';
  47         }
  48         else {
  49                 offset = 0L - offset;
  50                 offsign = '-';
  51         }
  52         offset = ( (offset / 3600) * 100 ) + ( offset % 60 );
  53
  54         switch(which_format) {
  55
  56                 case DATESTRING_RFC822:
  57                         return snprintf(
  58                                 buf, n,
  59                                 "%s, %02d %s %04d %02d:%02d:%02d %c%04ld",
  60                                 weekdays[t.tm_wday],
  61                                 t.tm_mday,
  62                                 months[t.tm_mon],
  63                                 t.tm_year + 1900,
  64                                 t.tm_hour,
  65                                 t.tm_min,
  66                                 t.tm_sec,
  67                                 offsign, offset
  68                                 );
  69                 break;
  70
  71                 case DATESTRING_IMAP:
  72                         return snprintf(
  73                                 buf, n,
  74                                 "%02d-%s-%04d %02d:%02d:%02d %c%04ld",
  75                                 t.tm_mday,
  76                                 months[t.tm_mon],
  77                                 t.tm_year + 1900,
  78                                 t.tm_hour,
  79                                 t.tm_min,
  80                                 t.tm_sec,
  81                                 offsign, offset
  82                                 );
  83                 break;
  84
  85         }
  86         return 0;
  87 }