2 dnl Copyright (C) 2002, 2003, 2005, 2006 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 2.60a and earlier.
10 # This redefinition can be removed once a new version of Autoconf is assumed.
11 # The redefinition is taken from
12 # <http://cvs.sv.gnu.org/viewcvs/*checkout*/autoconf/lib/autoconf/functions.m4?rev=1.108&root=autoconf>.
15 AC_DEFUN([AC_FUNC_MKTIME],
16 [AC_REQUIRE([AC_HEADER_TIME])dnl
17 AC_CHECK_HEADERS_ONCE(sys/time.h unistd.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 #ifdef TIME_WITH_SYS_TIME
23 # include <sys/time.h>
26 # ifdef HAVE_SYS_TIME_H
27 # include <sys/time.h>
40 # define alarm(X) /* empty */
43 /* Work around redefinition to rpl_putenv by other config tests. */
46 static time_t time_t_max;
47 static time_t time_t_min;
49 /* Values we'll use to set the TZ environment variable. */
50 static char *tz_strings[] = {
51 (char *) 0, "TZ=GMT0", "TZ=JST-9",
52 "TZ=EST+3EDT+2,M10.1.0/00:00:00,M2.3.0/00:00:00"
54 #define N_STRINGS (sizeof (tz_strings) / sizeof (tz_strings[0]))
56 /* Return 0 if mktime fails to convert a date in the spring-forward gap.
57 Based on a problem report from Andreas Jaeger. */
61 /* glibc (up to about 1998-10-07) failed this test. */
64 /* Use the portable POSIX.1 specification "TZ=PST8PDT,M4.1.0,M10.5.0"
65 instead of "TZ=America/Vancouver" in order to detect the bug even
66 on systems that don't support the Olson extension, or don't have the
67 full zoneinfo tables installed. */
68 putenv ("TZ=PST8PDT,M4.1.0,M10.5.0");
77 return mktime (&tm) != (time_t) -1;
85 return ! (lt = localtime (&now)) || mktime (lt) == now;
92 return (mktime_test1 (now)
93 && mktime_test1 ((time_t) (time_t_max - now))
94 && mktime_test1 ((time_t) (time_t_min + now)));
100 /* Based on code from Ariel Faigon. */
110 return 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))))
143 /* The correct answer for 2050-02-01 00:00:00 in Pacific time,
144 ignoring leap seconds. */
145 unsigned long int answer = 2527315200UL;
149 tm.tm_year = 2050 - 1900;
152 tm.tm_hour = tm.tm_min = tm.tm_sec = 0;
155 /* Use the portable POSIX.1 specification "TZ=PST8PDT,M4.1.0,M10.5.0"
156 instead of "TZ=America/Vancouver" in order to detect the bug even
157 on systems that don't support the Olson extension, or don't have the
158 full zoneinfo tables installed. */
159 putenv ("TZ=PST8PDT,M4.1.0,M10.5.0");
163 /* Check that the result is either a failure, or close enough
164 to the correct answer that we can assume the discrepancy is
165 due to leap seconds. */
166 return (t == (time_t) -1
167 || (0 < t && answer - 120 <= t && t <= answer + 120));
176 /* This test makes some buggy mktime implementations loop.
177 Give up after 60 seconds; a mktime slower than that
178 isn't worth using anyway. */
181 for (time_t_max = 1; 0 < time_t_max; time_t_max *= 2)
185 for (time_t_min = -1; (time_t) (time_t_min * 2) < 0; time_t_min *= 2)
187 delta = time_t_max / 997; /* a suitable prime number */
188 for (i = 0; i < N_STRINGS; i++)
191 putenv (tz_strings[i]);
193 for (t = 0; t <= time_t_max - delta; t += delta)
194 if (! mktime_test (t))
196 if (! (mktime_test ((time_t) 1)
197 && mktime_test ((time_t) (60 * 60))
198 && mktime_test ((time_t) (60 * 60 * 24))))
201 for (j = 1; 0 < j; j *= 2)
202 if (! bigtime_test (j))
204 if (! bigtime_test (j - 1))
207 return ! (irix_6_4_bug () && spring_forward_gap () && year_2050_test ());
209 [ac_cv_func_working_mktime=yes],
210 [ac_cv_func_working_mktime=no],
211 [ac_cv_func_working_mktime=no])])
212 if test $ac_cv_func_working_mktime = no; then
217 AC_DEFUN([gl_FUNC_MKTIME],
219 AC_REQUIRE([AC_FUNC_MKTIME])
220 if test $ac_cv_func_working_mktime = no; then
221 AC_DEFINE(mktime, rpl_mktime,
222 [Define to rpl_mktime if the replacement function should be used.])
227 # Prerequisites of lib/mktime.c.
228 AC_DEFUN([gl_PREREQ_MKTIME], [:])