1 files changed, 250 insertions, 0 deletions
diff --git a/m4/mktime.m4 b/m4/mktime.m4
new file mode 100644
index 0000000..f509bc4
--- /dev/null
+++ b/m4/mktime.m4
@@ -0,0 +1,250 @@
+# serial 24
+dnl Copyright (C) 2002-2003, 2005-2007, 2009-2012 Free Software Foundation,
+dnl Inc.
+dnl This file is free software; the Free Software Foundation
+dnl gives unlimited permission to copy and/or distribute it,
+dnl with or without modifications, as long as this notice is preserved.
+
+dnl From Jim Meyering.
+
+AC_DEFUN([gl_FUNC_MKTIME],
+[
+  AC_REQUIRE([gl_HEADER_TIME_H_DEFAULTS])
+
+  dnl We don't use AC_FUNC_MKTIME any more, because it is no longer maintained
+  dnl in Autoconf and because it invokes AC_LIBOBJ.
+  AC_CHECK_HEADERS_ONCE([unistd.h])
+  AC_CHECK_FUNCS_ONCE([alarm])
+  AC_REQUIRE([gl_MULTIARCH])
+  if test $APPLE_UNIVERSAL_BUILD = 1; then
+    # A universal build on Apple Mac OS X platforms.
+    # The test result would be 'yes' in 32-bit mode and 'no' in 64-bit mode.
+    # But we need a configuration result that is valid in both modes.
+    gl_cv_func_working_mktime=no
+  fi
+  AC_CACHE_CHECK([for working mktime], [gl_cv_func_working_mktime],
+    [AC_RUN_IFELSE(
+       [AC_LANG_SOURCE(
+[[/* Test program from Paul Eggert and Tony Leneis.  */
+#include <limits.h>
+#include <stdlib.h>
+#include <time.h>
+
+#ifdef HAVE_UNISTD_H
+# include <unistd.h>
+#endif
+
+#ifndef 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;
+static time_t time_t_min;
+
+/* Values we'll use to set the TZ environment variable.  */
+static char *tz_strings[] = {
+  (char *) 0, "TZ=GMT0", "TZ=JST-9",
+  "TZ=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]))
+
+/* Return 0 if mktime fails to convert a date in the spring-forward gap.
+   Based on a problem report from Andreas Jaeger.  */
+static int
+spring_forward_gap ()
+{
+  /* glibc (up to about 1998-10-07) failed this test. */
+  struct tm tm;
+
+  /* Use the portable POSIX.1 specification "TZ=PST8PDT,M4.1.0,M10.5.0"
+     instead of "TZ=America/Vancouver" in order to detect the bug even
+     on systems that don't support the Olson extension, or don't have the
+     full zoneinfo tables installed.  */
+  putenv ("TZ=PST8PDT,M4.1.0,M10.5.0");
+
+  tm.tm_year = 98;
+  tm.tm_mon = 3;
+  tm.tm_mday = 5;
+  tm.tm_hour = 2;
+  tm.tm_min = 0;
+  tm.tm_sec = 0;
+  tm.tm_isdst = -1;
+  return mktime (&tm) != (time_t) -1;
+}
+
+static int
+mktime_test1 (time_t now)
+{
+  struct tm *lt;
+  return ! (lt = localtime (&now)) || mktime (lt) == now;
+}
+
+static int
+mktime_test (time_t now)
+{
+  return (mktime_test1 (now)
+          && mktime_test1 ((time_t) (time_t_max - now))
+          && mktime_test1 ((time_t) (time_t_min + now)));
+}
+
+static int
+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);
+  return tm.tm_mon == 2 && tm.tm_mday == 31;
+}
+
+static int
+bigtime_test (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;
+  now = mktime (&tm);
+  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))))
+        return 0;
+    }
+  return 1;
+}
+
+static int
+year_2050_test ()
+{
+  /* The correct answer for 2050-02-01 00:00:00 in Pacific time,
+     ignoring leap seconds.  */
+  unsigned long int answer = 2527315200UL;
+
+  struct tm tm;
+  time_t t;
+  tm.tm_year = 2050 - 1900;
+  tm.tm_mon = 2 - 1;
+  tm.tm_mday = 1;
+  tm.tm_hour = tm.tm_min = tm.tm_sec = 0;
+  tm.tm_isdst = -1;
+
+  /* Use the portable POSIX.1 specification "TZ=PST8PDT,M4.1.0,M10.5.0"
+     instead of "TZ=America/Vancouver" in order to detect the bug even
+     on systems that don't support the Olson extension, or don't have the
+     full zoneinfo tables installed.  */
+  putenv ("TZ=PST8PDT,M4.1.0,M10.5.0");
+
+  t = mktime (&tm);
+
+  /* Check that the result is either a failure, or close enough
+     to the correct answer that we can assume the discrepancy is
+     due to leap seconds.  */
+  return (t == (time_t) -1
+          || (0 < t && answer - 120 <= t && t <= answer + 120));
+}
+
+int
+main ()
+{
+  int result = 0;
+  time_t t, delta;
+  int i, j;
+  int time_t_signed_magnitude = (time_t) ~ (time_t) 0 < (time_t) -1;
+  int time_t_signed = ! ((time_t) 0 < (time_t) -1);
+
+  /* This test makes some buggy mktime implementations loop.
+     Give up after 60 seconds; a mktime slower than that
+     isn't worth using anyway.  */
+  alarm (60);
+
+  time_t_max = (! time_t_signed
+                ? (time_t) -1
+                : ((((time_t) 1 << (sizeof (time_t) * CHAR_BIT - 2)) - 1)
+                   * 2 + 1));
+  time_t_min = (! time_t_signed
+                ? (time_t) 0
+                : time_t_signed_magnitude
+                ? ~ (time_t) 0
+                : ~ time_t_max);
+
+  delta = time_t_max / 997; /* a suitable prime number */
+  for (i = 0; i < N_STRINGS; i++)
+    {
+      if (tz_strings[i])
+        putenv (tz_strings[i]);
+
+      for (t = 0; t <= time_t_max - delta && (result & 1) == 0; t += delta)
+        if (! mktime_test (t))
+          result |= 1;
+      if ((result & 2) == 0
+          && ! (mktime_test ((time_t) 1)
+                && mktime_test ((time_t) (60 * 60))
+                && mktime_test ((time_t) (60 * 60 * 24))))
+        result |= 2;
+
+      for (j = 1; (result & 4) == 0; j <<= 1)
+        {
+          if (! bigtime_test (j))
+            result |= 4;
+          if (INT_MAX / 2 < j)
+            break;
+        }
+      if ((result & 8) == 0 && ! bigtime_test (INT_MAX))
+        result |= 8;
+    }
+  if (! irix_6_4_bug ())
+    result |= 16;
+  if (! spring_forward_gap ())
+    result |= 32;
+  if (! year_2050_test ())
+    result |= 64;
+  return result;
+}]])],
+       [gl_cv_func_working_mktime=yes],
+       [gl_cv_func_working_mktime=no],
+       [gl_cv_func_working_mktime=no])
+    ])
+
+  if test $gl_cv_func_working_mktime = no; then
+    REPLACE_MKTIME=1
+  else
+    REPLACE_MKTIME=0
+  fi
+])
+
+AC_DEFUN([gl_FUNC_MKTIME_INTERNAL], [
+  AC_REQUIRE([gl_FUNC_MKTIME])
+  if test $REPLACE_MKTIME = 0; then
+    dnl BeOS has __mktime_internal in libc, but other platforms don't.
+    AC_CHECK_FUNC([__mktime_internal],
+      [AC_DEFINE([mktime_internal], [__mktime_internal],
+         [Define to the real name of the mktime_internal function.])
+      ],
+      [dnl mktime works but it doesn't export __mktime_internal,
+       dnl so we need to substitute our own mktime implementation.
+       REPLACE_MKTIME=1
+      ])
+  fi
+])
+
+# Prerequisites of lib/mktime.c.
+AC_DEFUN([gl_PREREQ_MKTIME], [:])