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 2.61a 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/autoconf/lib/autoconf/functions.m4?rev=1.119>.
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>
41 # define alarm(X) /* empty */
44 /* Work around redefinition to rpl_putenv by other config tests. */
47 static time_t time_t_max;
48 static time_t time_t_min;
50 /* Values we'll use to set the TZ environment variable. */
51 static char *tz_strings[] = {
52 (char *) 0, "TZ=GMT0", "TZ=JST-9",
53 "TZ=EST+3EDT+2,M10.1.0/00:00:00,M2.3.0/00:00:00"
55 #define N_STRINGS (sizeof (tz_strings) / sizeof (tz_strings[0]))
57 /* Return 0 if mktime fails to convert a date in the spring-forward gap.
58 Based on a problem report from Andreas Jaeger. */
62 /* glibc (up to about 1998-10-07) failed this test. */
65 /* Use the portable POSIX.1 specification "TZ=PST8PDT,M4.1.0,M10.5.0"
66 instead of "TZ=America/Vancouver" in order to detect the bug even
67 on systems that don't support the Olson extension, or don't have the
68 full zoneinfo tables installed. */
69 putenv ("TZ=PST8PDT,M4.1.0,M10.5.0");
78 return mktime (&tm) != (time_t) -1;
86 return ! (lt = localtime (&now)) || mktime (lt) == now;
93 return (mktime_test1 (now)
94 && mktime_test1 ((time_t) (time_t_max - now))
95 && mktime_test1 ((time_t) (time_t_min + now)));
101 /* Based on code from Ariel Faigon. */
111 return tm.tm_mon == 2 && tm.tm_mday == 31;
120 tm.tm_year = tm.tm_mon = tm.tm_mday = tm.tm_hour = tm.tm_min = tm.tm_sec = j;
122 if (now != (time_t) -1)
124 struct tm *lt = localtime (&now);
126 && lt->tm_year == tm.tm_year
127 && lt->tm_mon == tm.tm_mon
128 && lt->tm_mday == tm.tm_mday
129 && lt->tm_hour == tm.tm_hour
130 && lt->tm_min == tm.tm_min
131 && lt->tm_sec == tm.tm_sec
132 && lt->tm_yday == tm.tm_yday
133 && lt->tm_wday == tm.tm_wday
134 && ((lt->tm_isdst < 0 ? -1 : 0 < lt->tm_isdst)
135 == (tm.tm_isdst < 0 ? -1 : 0 < tm.tm_isdst))))
144 /* The correct answer for 2050-02-01 00:00:00 in Pacific time,
145 ignoring leap seconds. */
146 unsigned long int answer = 2527315200UL;
150 tm.tm_year = 2050 - 1900;
153 tm.tm_hour = tm.tm_min = tm.tm_sec = 0;
156 /* Use the portable POSIX.1 specification "TZ=PST8PDT,M4.1.0,M10.5.0"
157 instead of "TZ=America/Vancouver" in order to detect the bug even
158 on systems that don't support the Olson extension, or don't have the
159 full zoneinfo tables installed. */
160 putenv ("TZ=PST8PDT,M4.1.0,M10.5.0");
164 /* Check that the result is either a failure, or close enough
165 to the correct answer that we can assume the discrepancy is
166 due to leap seconds. */
167 return (t == (time_t) -1
168 || (0 < t && answer - 120 <= t && t <= answer + 120));
177 /* This test makes some buggy mktime implementations loop.
178 Give up after 60 seconds; a mktime slower than that
179 isn't worth using anyway. */
184 t = (time_t_max << 1) + 1;
189 time_t_min = - ((time_t) ~ (time_t) 0 == (time_t) -1) - time_t_max;
191 delta = time_t_max / 997; /* a suitable prime number */
192 for (i = 0; i < N_STRINGS; i++)
195 putenv (tz_strings[i]);
197 for (t = 0; t <= time_t_max - delta; t += delta)
198 if (! mktime_test (t))
200 if (! (mktime_test ((time_t) 1)
201 && mktime_test ((time_t) (60 * 60))
202 && mktime_test ((time_t) (60 * 60 * 24))))
205 for (j = 1; ; j <<= 1)
206 if (! bigtime_test (j))
208 else if (INT_MAX / 2 < j)
210 if (! bigtime_test (INT_MAX))
213 return ! (irix_6_4_bug () && spring_forward_gap () && year_2050_test ());
215 [ac_cv_func_working_mktime=yes],
216 [ac_cv_func_working_mktime=no],
217 [ac_cv_func_working_mktime=no])])
218 if test $ac_cv_func_working_mktime = no; then
223 AC_DEFUN([gl_FUNC_MKTIME],
225 AC_REQUIRE([AC_FUNC_MKTIME])
226 if test $ac_cv_func_working_mktime = no; then
227 AC_DEFINE(mktime, rpl_mktime,
228 [Define to rpl_mktime if the replacement function should be used.])
233 # Prerequisites of lib/mktime.c.
234 AC_DEFUN([gl_PREREQ_MKTIME], [:])