time/tst-mktime2.c

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