src/src/tod.c

   1 /*************************************************
   2 *     Exim - an Internet mail transport agent    *
   3 *************************************************/
   4
   5 /* Copyright (c) University of Cambridge 1995 - 2018 */
   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.ddd +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 struct timeval now;
  56 struct tm * t;
  57
  58 gettimeofday(&now, NULL);
  59
  60 /* Styles that don't need local time */
  61
  62 switch(type)
  63   {
  64   case tod_epoch:
  65     (void) snprintf(CS timebuf, sizeof(timebuf), TIME_T_FMT, now.tv_sec);  /* Unix epoch format */
  66     return timebuf;     /* NB the above will be wrong if time_t is FP */
  67
  68   case tod_epoch_l:
  69     /* Unix epoch/usec format */
  70     (void) snprintf(CS timebuf, sizeof(timebuf), TIME_T_FMT "%06ld", now.tv_sec, (long) now.tv_usec );
  71     return timebuf;
  72
  73   case tod_zulu:
  74     t = gmtime(&now.tv_sec);
  75     (void) snprintf(CS timebuf, sizeof(timebuf), "%04u%02u%02u%02u%02u%02uZ",
  76       1900 + (uint)t->tm_year, 1 + (uint)t->tm_mon, (uint)t->tm_mday, (uint)t->tm_hour, (uint)t->tm_min,
  77       (uint)t->tm_sec);
  78     return timebuf;
  79   }
  80
  81 /* Vary log type according to timezone requirement */
  82
  83 if (type == tod_log) type = log_timezone ? tod_log_zone : tod_log_bare;
  84
  85 /* Convert to local time or UTC */
  86
  87 t = f.timestamps_utc ? gmtime(&now.tv_sec) : localtime(&now.tv_sec);
  88
  89 switch(type)
  90   {
  91   case tod_log_bare:          /* Format used in logging without timezone */
  92 #ifndef COMPILE_UTILITY
  93     if (LOGGING(millisec))
  94       snprintf(CS timebuf, sizeof(timebuf), "%04u-%02u-%02u %02u:%02u:%02u.%03u",
  95         1900 + (uint)t->tm_year, 1 + (uint)t->tm_mon, (uint)t->tm_mday,
  96         (uint)t->tm_hour, (uint)t->tm_min, (uint)t->tm_sec,
  97         (uint)(now.tv_usec/1000));
  98     else
  99 #endif
 100       snprintf(CS timebuf, sizeof(timebuf), "%04u-%02u-%02u %02u:%02u:%02u",
 101         1900 + (uint)t->tm_year, 1 + (uint)t->tm_mon, (uint)t->tm_mday,
 102         (uint)t->tm_hour, (uint)t->tm_min, (uint)t->tm_sec);
 103
 104     break;
 105
 106     /* Format used as suffix of log file name when 'log_datestamp' is active. For
 107     testing purposes, it changes the file every second. */
 108
 109 #ifdef TESTING_LOG_DATESTAMP
 110   case tod_log_datestamp_daily:
 111   case tod_log_datestamp_monthly:
 112     snprintf(CS timebuf, sizeof(timebuf), "%04u%02u%02u%02u%02u",
 113       1900 + (uint)t->tm_year, 1 + (uint)t->tm_mon, (uint)t->tm_mday,
 114       (uint)t->tm_hour, (uint)t->tm_min);
 115     break;
 116
 117 #else
 118   case tod_log_datestamp_daily:
 119     snprintf(CS timebuf, sizeof(timebuf), "%04u%02u%02u",
 120       1900 + (uint)t->tm_year, 1 + (uint)t->tm_mon, (uint)t->tm_mday);
 121     break;
 122
 123   case tod_log_datestamp_monthly:
 124 #ifndef COMPILE_UTILITY
 125     snprintf(CS timebuf, sizeof(timebuf), "%04u%02u",
 126       1900 + (uint)t->tm_year, 1 + (uint)t->tm_mon);
 127 #endif
 128     break;
 129 #endif
 130
 131     /* Format used in BSD inbox separator lines. Sort-of documented in RFC 976
 132     ("UUCP Mail Interchange Format Standard") but only by example, not by
 133     explicit definition. The examples show no timezone offsets, and some MUAs
 134     appear to be sensitive to this, so Exim has been changed to remove the
 135     timezone offsets that originally appeared. */
 136
 137   case tod_bsdin:
 138       {
 139       int len = Ustrftime(timebuf, sizeof(timebuf), "%a %b %d %H:%M:%S", t);
 140       Ustrftime(timebuf + len, sizeof(timebuf) - len, " %Y", t);
 141       }
 142     break;
 143
 144     /* Other types require the GMT offset to be calculated, or just set up in the
 145     case of UTC timestamping. We need to take a copy of the local time first. */
 146
 147   default:
 148       {
 149       int diff_hour, diff_min;
 150       struct tm local;
 151       struct tm * lp = &local;
 152       memcpy(lp, t, sizeof(struct tm));
 153
 154       if (f.timestamps_utc)
 155         diff_hour = diff_min = 0;
 156       else
 157         {
 158         struct tm * gmt = gmtime(&now.tv_sec);
 159
 160         if (local.tm_sec == gmt->tm_sec)        /* usual case */
 161           {
 162           diff_min = 60 * (local.tm_hour - gmt->tm_hour)
 163                     + local.tm_min - gmt->tm_min;
 164           if (local.tm_year != gmt->tm_year)
 165             diff_min += (local.tm_year > gmt->tm_year) ? 1440 : -1440;
 166           else if (local.tm_yday != gmt->tm_yday)
 167             diff_min += (local.tm_yday > gmt->tm_yday) ? 1440 : -1440;
 168           diff_hour = diff_min/60;
 169           diff_min  = abs(diff_min - diff_hour*60);
 170           }
 171         else                                    /* subminute offset, eg. TAI */
 172           {
 173           lp = gmt;                             /* pretend we're in UTC */
 174           diff_min = diff_hour = 0;
 175           }
 176         }
 177
 178       switch(type)
 179         {
 180         case tod_log_zone:          /* Format used in logging with timezone */
 181 #ifndef COMPILE_UTILITY
 182           if (LOGGING(millisec))
 183             (void) snprintf(CS timebuf, sizeof(timebuf),
 184               "%04u-%02u-%02u %02u:%02u:%02u.%03u %+03d%02d",
 185               1900 + (uint)lp->tm_year, 1 + (uint)lp->tm_mon, (uint)lp->tm_mday,
 186               (uint)lp->tm_hour, (uint)lp->tm_min, (uint)lp->tm_sec, (uint)(now.tv_usec/1000),
 187               diff_hour, diff_min);
 188           else
 189 #endif
 190             (void) snprintf(CS timebuf, sizeof(timebuf),
 191               "%04u-%02u-%02u %02u:%02u:%02u %+03d%02d",
 192               1900 + (uint)lp->tm_year, 1 + (uint)lp->tm_mon, (uint)lp->tm_mday,
 193               (uint)lp->tm_hour, (uint)lp->tm_min, (uint)lp->tm_sec,
 194               diff_hour, diff_min);
 195           break;
 196
 197         case tod_zone:              /* Just the timezone offset */
 198           (void) snprintf(CS timebuf, sizeof(timebuf), "%+03d%02d", diff_hour, diff_min);
 199           break;
 200
 201         /* tod_mbx: format used in MBX mailboxes - subtly different to tod_full */
 202
 203 #ifdef SUPPORT_MBX
 204         case tod_mbx:
 205           {
 206           int len = snprintf(CS timebuf, sizeof(timebuf),
 207             "%02u-", (uint)lp->tm_mday);
 208           len += Ustrftime(timebuf + len, sizeof(timebuf) - len,
 209             "%b-%Y %H:%M:%S", lp);
 210           (void) snprintf(CS timebuf + len, sizeof(timebuf)-len,
 211             " %+03d%02d", diff_hour, diff_min);
 212           }
 213           break;
 214 #endif
 215
 216         /* tod_full: format used in Received: headers (use as default just in case
 217         called with a junk type value) */
 218
 219         default:
 220           {
 221           int len = Ustrftime(timebuf, sizeof(timebuf), "%a, ", lp);
 222           len += snprintf(CS timebuf + len, sizeof(timebuf)-len,
 223             "%02u ", (uint)lp->tm_mday);
 224           len += Ustrftime(timebuf + len, sizeof(timebuf) - len,
 225             "%b %Y %H:%M:%S", lp);
 226           (void) snprintf(CS timebuf + len, sizeof(timebuf)-len,
 227             " %+03d%02d", diff_hour, diff_min);
 228           }
 229           break;
 230         }
 231       }
 232     break;
 233   }
 234
 235 return timebuf;
 236 }
 237
 238 /* End of tod.c */