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 /* True if the arithmetic type T is signed.  */
   9 #define TYPE_SIGNED(t) (! ((t) 0 < (t) -1))
  10
  11 /* The maximum and minimum values for the integer type T.  These
  12    macros have undefined behavior if T is signed and has padding bits.
  13    If this is a problem for you, please let us know how to fix it for
  14    your host.  */
  15 #define TYPE_MINIMUM(t) \
  16   ((t) (! TYPE_SIGNED (t) \
  17         ? (t) 0 \
  18         : ~ TYPE_MAXIMUM (t)))
  19 #define TYPE_MAXIMUM(t) \
  20   ((t) (! TYPE_SIGNED (t) \
  21         ? (t) -1 \
  22         : ((((t) 1 << (sizeof (t) * CHAR_BIT - 2)) - 1) * 2 + 1)))
  23
  24 #ifndef TIME_T_MIN
  25 # define TIME_T_MIN TYPE_MINIMUM (time_t)
  26 #endif
  27 #ifndef TIME_T_MAX
  28 # define TIME_T_MAX TYPE_MAXIMUM (time_t)
  29 #endif
  30
  31 /* Values we'll use to set the TZ environment variable.  */
  32 static const char *tz_strings[] =
  33   {
  34     (const char *) 0, "GMT0", "JST-9",
  35     "EST+3EDT+2,M10.1.0/00:00:00,M2.3.0/00:00:00"
  36   };
  37 #define N_STRINGS ((int) (sizeof (tz_strings) / sizeof (tz_strings[0])))
  38
  39 /* Fail if mktime fails to convert a date in the spring-forward gap.
  40    Based on a problem report from Andreas Jaeger.  */
  41 static void
  42 spring_forward_gap (void)
  43 {
  44   /* glibc (up to about 1998-10-07) failed this test. */
  45   struct tm tm;
  46
  47   /* Use the portable POSIX.1 specification "TZ=PST8PDT,M4.1.0,M10.5.0"
  48      instead of "TZ=America/Vancouver" in order to detect the bug even
  49      on systems that don't support the Olson extension, or don't have the
  50      full zoneinfo tables installed.  */
  51   setenv ("TZ", "PST8PDT,M4.1.0,M10.5.0", 1);
  52
  53   tm.tm_year = 98;
  54   tm.tm_mon = 3;
  55   tm.tm_mday = 5;
  56   tm.tm_hour = 2;
  57   tm.tm_min = 0;
  58   tm.tm_sec = 0;
  59   tm.tm_isdst = -1;
  60   if (mktime (&tm) == (time_t)-1)
  61     exit (1);
  62 }
  63
  64 static void
  65 mktime_test1 (time_t now)
  66 {
  67   struct tm *lt = localtime (&now);
  68   if (lt && mktime (lt) != now)
  69     exit (2);
  70 }
  71
  72 static void
  73 mktime_test (time_t now)
  74 {
  75   mktime_test1 (now);
  76   mktime_test1 ((time_t) (TIME_T_MAX - now));
  77   mktime_test1 ((time_t) (TIME_T_MIN + now));
  78 }
  79
  80 static void
  81 irix_6_4_bug (void)
  82 {
  83   /* Based on code from Ariel Faigon.  */
  84   struct tm tm;
  85   tm.tm_year = 96;
  86   tm.tm_mon = 3;
  87   tm.tm_mday = 0;
  88   tm.tm_hour = 0;
  89   tm.tm_min = 0;
  90   tm.tm_sec = 0;
  91   tm.tm_isdst = -1;
  92   mktime (&tm);
  93   if (tm.tm_mon != 2 || tm.tm_mday != 31)
  94     exit (3);
  95 }
  96
  97 static void
  98 bigtime_test (int j)
  99 {
 100   struct tm tm;
 101   time_t now;
 102   tm.tm_year = tm.tm_mon = tm.tm_mday = tm.tm_hour = tm.tm_min = tm.tm_sec = j;
 103   tm.tm_isdst = -1;
 104   now = mktime (&tm);
 105   if (now != (time_t) -1)
 106     {
 107       struct tm *lt = localtime (&now);
 108       if (! (lt
 109              && lt->tm_year == tm.tm_year
 110              && lt->tm_mon == tm.tm_mon
 111              && lt->tm_mday == tm.tm_mday
 112              && lt->tm_hour == tm.tm_hour
 113              && lt->tm_min == tm.tm_min
 114              && lt->tm_sec == tm.tm_sec
 115              && lt->tm_yday == tm.tm_yday
 116              && lt->tm_wday == tm.tm_wday
 117              && ((lt->tm_isdst < 0 ? -1 : 0 < lt->tm_isdst)
 118                   == (tm.tm_isdst < 0 ? -1 : 0 < tm.tm_isdst))))
 119         exit (4);
 120     }
 121 }
 122
 123 static int
 124 do_test (void)
 125 {
 126   time_t t, delta;
 127   int i;
 128   unsigned int j;
 129
 130   setenv ("TZ", "America/Sao_Paulo", 1);
 131   /* This test makes some buggy mktime implementations loop.
 132      Give up after 60 seconds; a mktime slower than that
 133      isn't worth using anyway.  */
 134   alarm (60);
 135
 136   delta = TIME_T_MAX / 997; /* a suitable prime number */
 137   for (i = 0; i < N_STRINGS; i++)
 138     {
 139       if (tz_strings[i])
 140         setenv ("TZ", tz_strings[i], 1);
 141
 142       for (t = 0; t <= TIME_T_MAX - delta; t += delta)
 143         mktime_test (t);
 144       mktime_test ((time_t) 1);
 145       mktime_test ((time_t) (60 * 60));
 146       mktime_test ((time_t) (60 * 60 * 24));
 147
 148       for (j = 1; j <= INT_MAX; j *= 2)
 149         bigtime_test (j);
 150       bigtime_test (j - 1);
 151     }
 152   irix_6_4_bug ();
 153   spring_forward_gap ();
 154   return 0;
 155 }
 156
 157 #define TEST_FUNCTION do_test ()
 158 #include "../test-skeleton.c"