src/src/tod.c

   1 /*************************************************
   2 *     Exim - an Internet mail transport agent    *
   3 *************************************************/
   4
   5 /* Copyright (c) University of Cambridge 1995 - 2009 */
   6 /* See the file NOTICE for conditions of use and distribution. */
   7
   8 /* A function for returning the time of day in various formats */
   9
  10
  11 #include "exim.h"
  12
  13 /* #define TESTING_LOG_DATESTAMP */
  14
  15
  16 static uschar timebuf[sizeof("www, dd-mmm-yyyy hh:mm:ss +zzzz")];
  17
  18
  19 /*************************************************
  20 *                Return timestamp                *
  21 *************************************************/
  22
  23 /* The log timestamp format is dd-mmm-yy so as to be non-confusing on both
  24 sides of the Atlantic. We calculate an explicit numerical offset from GMT for
  25 the full datestamp and BSD inbox datestamp. Note that on some systems
  26 localtime() and gmtime() re-use the same store, so we must save the local time
  27 values before calling gmtime(). If timestamps_utc is set, don't use
  28 localtime(); all times are then in UTC (with offset +0000).
  29
  30 There are also some contortions to get the day of the month without
  31 a leading zero for the full stamp, since Ustrftime() doesn't provide this
  32 option.
  33
  34 Argument:  type of timestamp required:
  35              tod_bsdin                  BSD inbox format
  36              tod_epoch                  Unix epoch format
  37              tod_epochl                 Unix epoch/usec format
  38              tod_full                   full date and time
  39              tod_log                    log file data line format,
  40                                           with zone if log_timezone is TRUE
  41              tod_log_bare               always without zone
  42              tod_log_datestamp_daily    for log file names when datestamped daily
  43              tod_log_datestamp_monthly  for log file names when datestamped monthly
  44              tod_log_zone               always with zone
  45              tod_mbx                    MBX inbox format
  46              tod_zone                   just the timezone offset
  47              tod_zulu                   time in 8601 zulu format
  48
  49 Returns:   pointer to fixed buffer containing the timestamp
  50 */
  51
  52 uschar *
  53 tod_stamp(int type)
  54 {
  55 time_t now;
  56 struct tm *t;
  57
  58 if (type == tod_epoch_l)
  59   {
  60   struct timeval tv;
  61   gettimeofday(&tv, NULL);
  62   /* Unix epoch/usec format */
  63   (void) sprintf(CS timebuf, TIME_T_FMT "%06ld", tv.tv_sec, (long) tv.tv_usec );
  64   return timebuf;
  65   }
  66
  67 now = time(NULL);
  68
  69 /* Vary log type according to timezone requirement */
  70
  71 if (type == tod_log) type = log_timezone? tod_log_zone : tod_log_bare;
  72
  73 /* Styles that don't need local time */
  74
  75 else if (type == tod_epoch)
  76   {
  77   (void) sprintf(CS timebuf, TIME_T_FMT, now);  /* Unix epoch format */
  78   return timebuf;       /* NB the above will be wrong if time_t is FP */
  79   }
  80
  81 else if (type == tod_zulu)
  82   {
  83   t = gmtime(&now);
  84   (void) sprintf(CS timebuf, "%04d%02d%02d%02d%02d%02dZ",
  85     1900 + t->tm_year, 1 + t->tm_mon, t->tm_mday, t->tm_hour, t->tm_min,
  86     t->tm_sec);
  87   return timebuf;
  88   }
  89
  90 /* Convert to local time or UTC */
  91
  92 t = timestamps_utc? gmtime(&now) : localtime(&now);
  93
  94 switch(type)
  95   {
  96   case tod_log_bare:          /* Format used in logging without timezone */
  97   (void) sprintf(CS timebuf, "%04d-%02d-%02d %02d:%02d:%02d",
  98     1900 + t->tm_year, 1 + t->tm_mon, t->tm_mday,
  99     t->tm_hour, t->tm_min, t->tm_sec);
 100   break;
 101
 102   /* Format used as suffix of log file name when 'log_datestamp' is active. For
 103   testing purposes, it changes the file every second. */
 104
 105   #ifdef TESTING_LOG_DATESTAMP
 106   case tod_log_datestamp_daily:
 107   case tod_log_datestamp_monthly:
 108   (void) sprintf(CS timebuf, "%04d%02d%02d%02d%02d",
 109     1900 + t->tm_year, 1 + t->tm_mon, t->tm_mday, t->tm_hour, t->tm_min);
 110   break;
 111
 112   #else
 113   case tod_log_datestamp_daily:
 114   (void) sprintf(CS timebuf, "%04d%02d%02d",
 115     1900 + t->tm_year, 1 + t->tm_mon, t->tm_mday);
 116   break;
 117
 118   case tod_log_datestamp_monthly:
 119   (void) sprintf(CS timebuf, "%04d%02d",
 120     1900 + t->tm_year, 1 + t->tm_mon);
 121   break;
 122   #endif
 123
 124   /* Format used in BSD inbox separator lines. Sort-of documented in RFC 976
 125   ("UUCP Mail Interchange Format Standard") but only by example, not by
 126   explicit definition. The examples show no timezone offsets, and some MUAs
 127   appear to be sensitive to this, so Exim has been changed to remove the
 128   timezone offsets that originally appeared. */
 129
 130   case tod_bsdin:
 131     {
 132     int len = Ustrftime(timebuf, sizeof(timebuf), "%a %b %d %H:%M:%S", t);
 133     Ustrftime(timebuf + len, sizeof(timebuf) - len, " %Y", t);
 134     }
 135   break;
 136
 137   /* Other types require the GMT offset to be calculated, or just set up in the
 138   case of UTC timestamping. We need to take a copy of the local time first. */
 139
 140   default:
 141     {
 142     int diff_hour, diff_min;
 143     struct tm local;
 144     memcpy(&local, t, sizeof(struct tm));
 145
 146     if (timestamps_utc)
 147       {
 148       diff_hour = diff_min = 0;
 149       }
 150     else
 151       {
 152       struct tm *gmt = gmtime(&now);
 153       diff_min = 60*(local.tm_hour - gmt->tm_hour) + local.tm_min - gmt->tm_min;
 154       if (local.tm_year != gmt->tm_year)
 155         diff_min += (local.tm_year > gmt->tm_year)? 1440 : -1440;
 156       else if (local.tm_yday != gmt->tm_yday)
 157         diff_min += (local.tm_yday > gmt->tm_yday)? 1440 : -1440;
 158       diff_hour = diff_min/60;
 159       diff_min  = abs(diff_min - diff_hour*60);
 160       }
 161
 162     switch(type)
 163       {
 164       case tod_log_zone:          /* Format used in logging with timezone */
 165       (void) sprintf(CS timebuf, "%04d-%02d-%02d %02d:%02d:%02d %+03d%02d",
 166         1900 + local.tm_year, 1 + local.tm_mon, local.tm_mday,
 167         local.tm_hour, local.tm_min, local.tm_sec,
 168         diff_hour, diff_min);
 169       break;
 170
 171       case tod_zone:              /* Just the timezone offset */
 172       (void) sprintf(CS timebuf, "%+03d%02d", diff_hour, diff_min);
 173       break;
 174
 175       /* tod_mbx: format used in MBX mailboxes - subtly different to tod_full */
 176
 177       #ifdef SUPPORT_MBX
 178       case tod_mbx:
 179         {
 180         int len;
 181         (void) sprintf(CS timebuf, "%02d-", local.tm_mday);
 182         len = Ustrlen(timebuf);
 183         len += Ustrftime(timebuf + len, sizeof(timebuf) - len, "%b-%Y %H:%M:%S",
 184           &local);
 185         (void) sprintf(CS timebuf + len, " %+03d%02d", diff_hour, diff_min);
 186         }
 187       break;
 188       #endif
 189
 190       /* tod_full: format used in Received: headers (use as default just in case
 191       called with a junk type value) */
 192
 193       default:
 194         {
 195         int len = Ustrftime(timebuf, sizeof(timebuf), "%a, ", &local);
 196         (void) sprintf(CS timebuf + len, "%02d ", local.tm_mday);
 197         len += Ustrlen(timebuf + len);
 198         len += Ustrftime(timebuf + len, sizeof(timebuf) - len, "%b %Y %H:%M:%S",
 199           &local);
 200         (void) sprintf(CS timebuf + len, " %+03d%02d", diff_hour, diff_min);
 201         }
 202       break;
 203       }
 204     }
 205   break;
 206   }
 207
 208 return timebuf;
 209 }
 210
 211 /* End of tod.c */