src/time/asctime_r.c

   1 #include <time.h>
   2 #include <stdio.h>
   3 #include <langinfo.h>
   4 #include "locale_impl.h"
   5 #include "atomic.h"
   6
   7 char *__asctime_r(const struct tm *restrict tm, char *restrict buf)
   8 {
   9         if (snprintf(buf, 26, "%.3s %.3s%3d %.2d:%.2d:%.2d %d\n",
  10                 __nl_langinfo_l(ABDAY_1+tm->tm_wday, C_LOCALE),
  11                 __nl_langinfo_l(ABMON_1+tm->tm_mon, C_LOCALE),
  12                 tm->tm_mday, tm->tm_hour,
  13                 tm->tm_min, tm->tm_sec,
  14                 1900 + tm->tm_year) >= 26)
  15         {
  16                 /* ISO C requires us to use the above format string,
  17                  * even if it will not fit in the buffer. Thus asctime_r
  18                  * is _supposed_ to crash if the fields in tm are too large.
  19                  * We follow this behavior and crash "gracefully" to warn
  20                  * application developers that they may not be so lucky
  21                  * on other implementations (e.g. stack smashing..).
  22                  */
  23                 a_crash();
  24         }
  25         return buf;
  26 }
  27
  28 weak_alias(__asctime_r, asctime_r);