2 dnl Copyright (C) 2002, 2003, 2005 Free Software Foundation, Inc.
3 dnl This file is free software; the Free Software Foundation
4 dnl gives unlimited permission to copy and/or distribute it,
5 dnl with or without modifications, as long as this notice is preserved.
9 # Redefine AC_FUNC_MKTIME, to fix a bug in Autoconf 2.57 and earlier.
10 # This redefinition can be removed once a new version of Autoconf comes out.
11 # The redefinition is taken from
12 # <http://savannah.gnu.org/cgi-bin/viewcvs/*checkout*/autoconf/autoconf/lib/autoconf/functions.m4?rev=1.78>.
15 AC_DEFUN([AC_FUNC_MKTIME],
16 [AC_REQUIRE([AC_HEADER_TIME])dnl
17 AC_CHECK_HEADERS_ONCE(sys/time.h)
18 AC_CHECK_FUNCS_ONCE(alarm)
19 AC_CACHE_CHECK([for working mktime], ac_cv_func_working_mktime,
20 [AC_RUN_IFELSE([AC_LANG_SOURCE(
21 [[/* Test program from Paul Eggert and Tony Leneis. */
22 #if TIME_WITH_SYS_TIME
23 # include <sys/time.h>
27 # include <sys/time.h>
37 # define alarm(X) /* empty */
40 /* Work around redefinition to rpl_putenv by other config tests. */
43 static time_t time_t_max;
44 static time_t time_t_min;
46 /* Values we'll use to set the TZ environment variable. */
47 static char *tz_strings[] = {
48 (char *) 0, "TZ=GMT0", "TZ=JST-9",
49 "TZ=EST+3EDT+2,M10.1.0/00:00:00,M2.3.0/00:00:00"
51 #define N_STRINGS (sizeof (tz_strings) / sizeof (tz_strings[0]))
53 /* Fail if mktime fails to convert a date in the spring-forward gap.
54 Based on a problem report from Andreas Jaeger. */
58 /* glibc (up to about 1998-10-07) failed this test. */
61 /* Use the portable POSIX.1 specification "TZ=PST8PDT,M4.1.0,M10.5.0"
62 instead of "TZ=America/Vancouver" in order to detect the bug even
63 on systems that don't support the Olson extension, or don't have the
64 full zoneinfo tables installed. */
65 putenv ("TZ=PST8PDT,M4.1.0,M10.5.0");
74 if (mktime (&tm) == (time_t)-1)
83 if ((lt = localtime (&now)) && mktime (lt) != now)
92 mktime_test1 ((time_t) (time_t_max - now));
93 mktime_test1 ((time_t) (time_t_min + now));
99 /* Based on code from Ariel Faigon. */
109 if (tm.tm_mon != 2 || tm.tm_mday != 31)
119 tm.tm_year = tm.tm_mon = tm.tm_mday = tm.tm_hour = tm.tm_min = tm.tm_sec = j;
121 if (now != (time_t) -1)
123 struct tm *lt = localtime (&now);
125 && lt->tm_year == tm.tm_year
126 && lt->tm_mon == tm.tm_mon
127 && lt->tm_mday == tm.tm_mday
128 && lt->tm_hour == tm.tm_hour
129 && lt->tm_min == tm.tm_min
130 && lt->tm_sec == tm.tm_sec
131 && lt->tm_yday == tm.tm_yday
132 && lt->tm_wday == tm.tm_wday
133 && ((lt->tm_isdst < 0 ? -1 : 0 < lt->tm_isdst)
134 == (tm.tm_isdst < 0 ? -1 : 0 < tm.tm_isdst))))
145 /* This test makes some buggy mktime implementations loop.
146 Give up after 60 seconds; a mktime slower than that
147 isn't worth using anyway. */
150 for (time_t_max = 1; 0 < time_t_max; time_t_max *= 2)
154 for (time_t_min = -1; (time_t) (time_t_min * 2) < 0; time_t_min *= 2)
156 delta = time_t_max / 997; /* a suitable prime number */
157 for (i = 0; i < N_STRINGS; i++)
160 putenv (tz_strings[i]);
162 for (t = 0; t <= time_t_max - delta; t += delta)
164 mktime_test ((time_t) 1);
165 mktime_test ((time_t) (60 * 60));
166 mktime_test ((time_t) (60 * 60 * 24));
168 for (j = 1; 0 < j; j *= 2)
170 bigtime_test (j - 1);
173 spring_forward_gap ();
176 [ac_cv_func_working_mktime=yes],
177 [ac_cv_func_working_mktime=no],
178 [ac_cv_func_working_mktime=no])])
179 if test $ac_cv_func_working_mktime = no; then
184 AC_DEFUN([gl_FUNC_MKTIME],
186 AC_REQUIRE([AC_FUNC_MKTIME])
187 if test $ac_cv_func_working_mktime = no; then
188 AC_DEFINE(mktime, rpl_mktime,
189 [Define to rpl_mktime if the replacement function should be used.])
194 # Prerequisites of lib/mktime.c.
195 AC_DEFUN([gl_PREREQ_MKTIME], [:])