time/tst-mktime2.c

   1 /* Test program from Paul Eggert and Tony Leneis.  */
   2
   3 #include <limits.h>
   4 #include <time.h>
   5 #include <stdlib.h>
   6 #include <unistd.h>
   7
   8 static time_t time_t_max;
   9 static time_t time_t_min;
  10
  11 /* Values we'll use to set the TZ environment variable.  */
  12 static const char *tz_strings[] =
  13   {
  14     (const char *) 0, "GMT0", "JST-9",
  15     "EST+3EDT+2,M10.1.0/00:00:00,M2.3.0/00:00:00"
  16   };
  17 #define N_STRINGS ((int) (sizeof (tz_strings) / sizeof (tz_strings[0])))
  18
  19 /* Fail if mktime fails to convert a date in the spring-forward gap.
  20    Based on a problem report from Andreas Jaeger.  */
  21 static void
  22 spring_forward_gap (void)
  23 {
  24   /* glibc (up to about 1998-10-07) failed this test. */
  25   struct tm tm;
  26
  27   /* Use the portable POSIX.1 specification "TZ=PST8PDT,M4.1.0,M10.5.0"
  28      instead of "TZ=America/Vancouver" in order to detect the bug even
  29      on systems that don't support the Olson extension, or don't have the
  30      full zoneinfo tables installed.  */
  31   setenv ("TZ", "PST8PDT,M4.1.0,M10.5.0", 1);
  32
  33   tm.tm_year = 98;
  34   tm.tm_mon = 3;
  35   tm.tm_mday = 5;
  36   tm.tm_hour = 2;
  37   tm.tm_min = 0;
  38   tm.tm_sec = 0;
  39   tm.tm_isdst = -1;
  40   if (mktime (&tm) == (time_t)-1)
  41     exit (1);
  42 }
  43
  44 static void
  45 mktime_test1 (time_t now)
  46 {
  47   struct tm *lt = localtime (&now);
  48   if (lt && mktime (lt) != now)
  49     exit (2);
  50 }
  51
  52 static void
  53 mktime_test (time_t now)
  54 {
  55   mktime_test1 (now);
  56   mktime_test1 ((time_t) (time_t_max - now));
  57   mktime_test1 ((time_t) (time_t_min + now));
  58 }
  59
  60 static void
  61 irix_6_4_bug (void)
  62 {
  63   /* Based on code from Ariel Faigon.  */
  64   struct tm tm;
  65   tm.tm_year = 96;
  66   tm.tm_mon = 3;
  67   tm.tm_mday = 0;
  68   tm.tm_hour = 0;
  69   tm.tm_min = 0;
  70   tm.tm_sec = 0;
  71   tm.tm_isdst = -1;
  72   mktime (&tm);
  73   if (tm.tm_mon != 2 || tm.tm_mday != 31)
  74     exit (3);
  75 }
  76
  77 static void
  78 bigtime_test (int j)
  79 {
  80   struct tm tm;
  81   time_t now;
  82   tm.tm_year = tm.tm_mon = tm.tm_mday = tm.tm_hour = tm.tm_min = tm.tm_sec = j;
  83   tm.tm_isdst = -1;
  84   now = mktime (&tm);
  85   if (now != (time_t) -1)
  86     {
  87       struct tm *lt = localtime (&now);
  88       if (! (lt
  89              && lt->tm_year == tm.tm_year
  90              && lt->tm_mon == tm.tm_mon
  91              && lt->tm_mday == tm.tm_mday
  92              && lt->tm_hour == tm.tm_hour
  93              && lt->tm_min == tm.tm_min
  94              && lt->tm_sec == tm.tm_sec
  95              && lt->tm_yday == tm.tm_yday
  96              && lt->tm_wday == tm.tm_wday
  97              && ((lt->tm_isdst < 0 ? -1 : 0 < lt->tm_isdst)
  98                   == (tm.tm_isdst < 0 ? -1 : 0 < tm.tm_isdst))))
  99         exit (4);
 100     }
 101 }
 102
 103 static int
 104 do_test (void)
 105 {
 106   time_t t, delta;
 107   int i;
 108   unsigned int j;
 109
 110   setenv ("TZ", "America/Sao_Paulo", 1);
 111   /* This test makes some buggy mktime implementations loop.
 112      Give up after 60 seconds; a mktime slower than that
 113      isn't worth using anyway.  */
 114   alarm (60);
 115
 116   for (time_t_max = 1; 0 < time_t_max; time_t_max *= 2)
 117     continue;
 118   time_t_max--;
 119   if ((time_t) -1 < 0)
 120     for (time_t_min = -1; (time_t) (time_t_min * 2) < 0; time_t_min *= 2)
 121       continue;
 122   delta = time_t_max / 997; /* a suitable prime number */
 123   for (i = 0; i < N_STRINGS; i++)
 124     {
 125       if (tz_strings[i])
 126         setenv ("TZ", tz_strings[i], 1);
 127
 128       for (t = 0; t <= time_t_max - delta; t += delta)
 129         mktime_test (t);
 130       mktime_test ((time_t) 1);
 131       mktime_test ((time_t) (60 * 60));
 132       mktime_test ((time_t) (60 * 60 * 24));
 133
 134       for (j = 1; j <= INT_MAX; j *= 2)
 135         bigtime_test (j);
 136       bigtime_test (j - 1);
 137     }
 138   irix_6_4_bug ();
 139   spring_forward_gap ();
 140   return 0;
 141 }
 142
 143 #define TEST_FUNCTION do_test ()
 144 #include "../test-skeleton.c"