+
+#if HAVE_UNISTD_H
+# include <unistd.h>
+#endif
+
+#if !HAVE_ALARM
+# define alarm(X) /* empty */
+#endif
+
+/* Work around redefinition to rpl_putenv by other config tests. */
+#undef putenv
+
+static time_t time_t_max;
+
+/* Values we'll use to set the TZ environment variable. */
+static const char *const tz_strings[] = {
+ (const char *) 0, "GMT0", "JST-9",
+ "EST+3EDT+2,M10.1.0/00:00:00,M2.3.0/00:00:00"
+};
+#define N_STRINGS (sizeof (tz_strings) / sizeof (tz_strings[0]))
+
+static void
+mktime_test (now)
+ time_t now;
+{
+ struct tm *lt;
+ if ((lt = localtime (&now)) && mktime (lt) != now)
+ exit (1);
+ now = time_t_max - now;
+ if ((lt = localtime (&now)) && mktime (lt) != now)
+ exit (1);
+}
+
+static void
+irix_6_4_bug ()
+{
+ /* Based on code from Ariel Faigon. */
+ struct tm tm;
+ tm.tm_year = 96;
+ tm.tm_mon = 3;
+ tm.tm_mday = 0;
+ tm.tm_hour = 0;
+ tm.tm_min = 0;
+ tm.tm_sec = 0;
+ tm.tm_isdst = -1;
+ mktime (&tm);
+ if (tm.tm_mon != 2 || tm.tm_mday != 31)
+ exit (1);
+}
+
+static void
+bigtime_test (j)
+ int j;
+{
+ struct tm tm;
+ time_t now;
+ tm.tm_year = tm.tm_mon = tm.tm_mday = tm.tm_hour = tm.tm_min = tm.tm_sec = j;
+ /* This test makes some buggy mktime implementations loop.
+ Give up after 10 seconds. */
+ alarm (10);
+ now = mktime (&tm);
+ alarm (0);
+ if (now != (time_t) -1)
+ {
+ struct tm *lt = localtime (&now);
+ if (! (lt
+ && lt->tm_year == tm.tm_year
+ && lt->tm_mon == tm.tm_mon
+ && lt->tm_mday == tm.tm_mday
+ && lt->tm_hour == tm.tm_hour
+ && lt->tm_min == tm.tm_min
+ && lt->tm_sec == tm.tm_sec
+ && lt->tm_yday == tm.tm_yday
+ && lt->tm_wday == tm.tm_wday
+ && ((lt->tm_isdst < 0 ? -1 : 0 < lt->tm_isdst)
+ == (tm.tm_isdst < 0 ? -1 : 0 < tm.tm_isdst))))
+ exit (1);
+ }
+}
+