AC_DEFUN([AC_FUNC_MKTIME],
[AC_CHECK_HEADERS_ONCE(unistd.h)
AC_CHECK_FUNCS_ONCE(alarm)
AC_CACHE_CHECK([for working mktime], ac_cv_func_working_mktime,
[AC_RUN_IFELSE([AC_LANG_SOURCE(
[[/* Test program from Paul Eggert and Tony Leneis. */
/* Work around redefinition to rpl_putenv by other config tests. */
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"
};
/* 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 (now)
time_t now;
{
struct tm *lt;
return ! (lt = localtime (&now)) || mktime (lt) == now;
}
static int
mktime_test (now)
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 (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;
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 ()
{
time_t t, delta;
int i, j;
/* 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);
for (;;)
{
t = (time_t_max << 1) + 1;
if (t <= time_t_max)
break;
time_t_max = t;
}
time_t_min = - ((time_t) ~ (time_t) 0 == (time_t) -1) - 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; t += delta)
if (! mktime_test (t))
return 1;
if (! (mktime_test ((time_t) 1)
&& mktime_test ((time_t) (60 * 60))
&& mktime_test ((time_t) (60 * 60 * 24))))
return 1;
for (j = 1; ; j <<= 1)
if (! bigtime_test (j))
return 1;
else if (INT_MAX / 2 < j)
break;
if (! bigtime_test (INT_MAX))
return 1;
}
return ! (irix_6_4_bug () && spring_forward_gap () && year_2050_test ());
}]])],
[ac_cv_func_working_mktime=yes],
[ac_cv_func_working_mktime=no],
[ac_cv_func_working_mktime=no])])
if test $ac_cv_func_working_mktime = no; then
AC_LIBOBJ([mktime])
fi
])
AC_DEFUN([gl_FUNC_MKTIME],
[
AC_FUNC_MKTIME
if test $ac_cv_func_working_mktime = no; then
AC_DEFINE(mktime, rpl_mktime,
[Define to rpl_mktime if the replacement function should be used.])
gl_PREREQ_MKTIME
fi
])
AC_DEFUN([gl_PREREQ_MKTIME],
[
AC_REQUIRE([AC_C_INLINE])
])