time/bug-mktime4.c

   1 #include <time.h>
   2 #include <errno.h>
   3 #include <limits.h>
   4 #include <stdbool.h>
   5 #include <stdio.h>
   6 #include <string.h>
   7
   8 static bool
   9 equal_tm (struct tm const *t, struct tm const *u)
  10 {
  11   return (t->tm_sec == u->tm_sec && t->tm_min == u->tm_min
  12           && t->tm_hour == u->tm_hour && t->tm_mday == u->tm_mday
  13           && t->tm_mon == u->tm_mon && t->tm_year == u->tm_year
  14           && t->tm_wday == u->tm_wday && t->tm_yday == u->tm_yday
  15           && t->tm_isdst == u->tm_isdst && t->tm_gmtoff == u->tm_gmtoff
  16           && t->tm_zone == u->tm_zone);
  17 }
  18
  19 static int
  20 do_test (void)
  21 {
  22   /* Calculate minimum time_t value.  This would be simpler with C11,
  23      which has _Generic, but we cannot assume C11.  It would also
  24      be simpler with intprops.h, which has TYPE_MINIMUM, but it's
  25      better not to use glibc internals.  */
  26   time_t time_t_min = -1;
  27   time_t_min = (0 < time_t_min ? 0
  28                 : sizeof time_t_min == sizeof (long int) ? LONG_MIN
  29                 : sizeof time_t_min == sizeof (long long int) ? LLONG_MIN
  30                 : 1);
  31   if (time_t_min == 1)
  32     {
  33       printf ("unknown time type\n");
  34       return 1;
  35     }
  36   time_t ymin = time_t_min / 60 / 60 / 24 / 366;
  37   bool mktime_should_fail = ymin == 0 || INT_MIN + 1900 < ymin + 1970;
  38
  39   struct tm tm0 = { .tm_year = INT_MIN, .tm_mday = 1, .tm_wday = -1 };
  40   struct tm tm = tm0;
  41   errno = 0;
  42   time_t t = mktime (&tm);
  43   long long int llt = t;
  44   bool mktime_failed = tm.tm_wday == tm0.tm_wday;
  45
  46   if (mktime_failed)
  47     {
  48       if (! mktime_should_fail)
  49         {
  50           printf ("mktime failed but should have succeeded\n");
  51           return 1;
  52         }
  53       if (errno == 0)
  54         {
  55           printf ("mktime failed without setting errno");
  56           return 1;
  57         }
  58       if (t != (time_t) -1)
  59         {
  60           printf ("mktime returned %lld but did not set tm_wday\n", llt);
  61           return 1;
  62         }
  63       if (! equal_tm (&tm, &tm0))
  64         {
  65           printf ("mktime (P) failed but modified *P\n");
  66           return 1;
  67         }
  68     }
  69   else
  70     {
  71       if (mktime_should_fail)
  72         {
  73           printf ("mktime succeeded but should have failed\n");
  74           return 1;
  75         }
  76       struct tm *lt = localtime (&t);
  77       if (lt == NULL)
  78         {
  79           printf ("mktime returned a value rejected by localtime\n");
  80           return 1;
  81         }
  82       if (! equal_tm (lt, &tm))
  83         {
  84           printf ("mktime result does not match localtime result\n");
  85           return 1;
  86         }
  87     }
  88   return 0;
  89 }
  90
  91 #define TIMEOUT 1000
  92 #include "support/test-driver.c"