| 1 | # serial 25 |
| 2 | dnl Copyright (C) 2002-2003, 2005-2007, 2009-2013 Free Software Foundation, |
| 3 | dnl Inc. |
| 4 | dnl This file is free software; the Free Software Foundation |
| 5 | dnl gives unlimited permission to copy and/or distribute it, |
| 6 | dnl with or without modifications, as long as this notice is preserved. |
| 7 | |
| 8 | dnl From Jim Meyering. |
| 9 | |
| 10 | AC_DEFUN([gl_FUNC_MKTIME], |
| 11 | [ |
| 12 | AC_REQUIRE([gl_HEADER_TIME_H_DEFAULTS]) |
| 13 | |
| 14 | dnl We don't use AC_FUNC_MKTIME any more, because it is no longer maintained |
| 15 | dnl in Autoconf and because it invokes AC_LIBOBJ. |
| 16 | AC_CHECK_HEADERS_ONCE([unistd.h]) |
| 17 | AC_CHECK_DECLS_ONCE([alarm]) |
| 18 | AC_REQUIRE([gl_MULTIARCH]) |
| 19 | if test $APPLE_UNIVERSAL_BUILD = 1; then |
| 20 | # A universal build on Apple Mac OS X platforms. |
| 21 | # The test result would be 'yes' in 32-bit mode and 'no' in 64-bit mode. |
| 22 | # But we need a configuration result that is valid in both modes. |
| 23 | gl_cv_func_working_mktime=no |
| 24 | fi |
| 25 | AC_CACHE_CHECK([for working mktime], [gl_cv_func_working_mktime], |
| 26 | [AC_RUN_IFELSE( |
| 27 | [AC_LANG_SOURCE( |
| 28 | [[/* Test program from Paul Eggert and Tony Leneis. */ |
| 29 | #include <limits.h> |
| 30 | #include <stdlib.h> |
| 31 | #include <time.h> |
| 32 | |
| 33 | #ifdef HAVE_UNISTD_H |
| 34 | # include <unistd.h> |
| 35 | #endif |
| 36 | |
| 37 | #if HAVE_DECL_ALARM |
| 38 | # include <signal.h> |
| 39 | #endif |
| 40 | |
| 41 | /* Work around redefinition to rpl_putenv by other config tests. */ |
| 42 | #undef putenv |
| 43 | |
| 44 | static time_t time_t_max; |
| 45 | static time_t time_t_min; |
| 46 | |
| 47 | /* Values we'll use to set the TZ environment variable. */ |
| 48 | static char *tz_strings[] = { |
| 49 | (char *) 0, "TZ=GMT0", "TZ=JST-9", |
| 50 | "TZ=EST+3EDT+2,M10.1.0/00:00:00,M2.3.0/00:00:00" |
| 51 | }; |
| 52 | #define N_STRINGS (sizeof (tz_strings) / sizeof (tz_strings[0])) |
| 53 | |
| 54 | /* Return 0 if mktime fails to convert a date in the spring-forward gap. |
| 55 | Based on a problem report from Andreas Jaeger. */ |
| 56 | static int |
| 57 | spring_forward_gap () |
| 58 | { |
| 59 | /* glibc (up to about 1998-10-07) failed this test. */ |
| 60 | struct tm tm; |
| 61 | |
| 62 | /* Use the portable POSIX.1 specification "TZ=PST8PDT,M4.1.0,M10.5.0" |
| 63 | instead of "TZ=America/Vancouver" in order to detect the bug even |
| 64 | on systems that don't support the Olson extension, or don't have the |
| 65 | full zoneinfo tables installed. */ |
| 66 | putenv ("TZ=PST8PDT,M4.1.0,M10.5.0"); |
| 67 | |
| 68 | tm.tm_year = 98; |
| 69 | tm.tm_mon = 3; |
| 70 | tm.tm_mday = 5; |
| 71 | tm.tm_hour = 2; |
| 72 | tm.tm_min = 0; |
| 73 | tm.tm_sec = 0; |
| 74 | tm.tm_isdst = -1; |
| 75 | return mktime (&tm) != (time_t) -1; |
| 76 | } |
| 77 | |
| 78 | static int |
| 79 | mktime_test1 (time_t now) |
| 80 | { |
| 81 | struct tm *lt; |
| 82 | return ! (lt = localtime (&now)) || mktime (lt) == now; |
| 83 | } |
| 84 | |
| 85 | static int |
| 86 | mktime_test (time_t now) |
| 87 | { |
| 88 | return (mktime_test1 (now) |
| 89 | && mktime_test1 ((time_t) (time_t_max - now)) |
| 90 | && mktime_test1 ((time_t) (time_t_min + now))); |
| 91 | } |
| 92 | |
| 93 | static int |
| 94 | irix_6_4_bug () |
| 95 | { |
| 96 | /* Based on code from Ariel Faigon. */ |
| 97 | struct tm tm; |
| 98 | tm.tm_year = 96; |
| 99 | tm.tm_mon = 3; |
| 100 | tm.tm_mday = 0; |
| 101 | tm.tm_hour = 0; |
| 102 | tm.tm_min = 0; |
| 103 | tm.tm_sec = 0; |
| 104 | tm.tm_isdst = -1; |
| 105 | mktime (&tm); |
| 106 | return tm.tm_mon == 2 && tm.tm_mday == 31; |
| 107 | } |
| 108 | |
| 109 | static int |
| 110 | bigtime_test (int j) |
| 111 | { |
| 112 | struct tm tm; |
| 113 | time_t now; |
| 114 | tm.tm_year = tm.tm_mon = tm.tm_mday = tm.tm_hour = tm.tm_min = tm.tm_sec = j; |
| 115 | now = mktime (&tm); |
| 116 | if (now != (time_t) -1) |
| 117 | { |
| 118 | struct tm *lt = localtime (&now); |
| 119 | if (! (lt |
| 120 | && lt->tm_year == tm.tm_year |
| 121 | && lt->tm_mon == tm.tm_mon |
| 122 | && lt->tm_mday == tm.tm_mday |
| 123 | && lt->tm_hour == tm.tm_hour |
| 124 | && lt->tm_min == tm.tm_min |
| 125 | && lt->tm_sec == tm.tm_sec |
| 126 | && lt->tm_yday == tm.tm_yday |
| 127 | && lt->tm_wday == tm.tm_wday |
| 128 | && ((lt->tm_isdst < 0 ? -1 : 0 < lt->tm_isdst) |
| 129 | == (tm.tm_isdst < 0 ? -1 : 0 < tm.tm_isdst)))) |
| 130 | return 0; |
| 131 | } |
| 132 | return 1; |
| 133 | } |
| 134 | |
| 135 | static int |
| 136 | year_2050_test () |
| 137 | { |
| 138 | /* The correct answer for 2050-02-01 00:00:00 in Pacific time, |
| 139 | ignoring leap seconds. */ |
| 140 | unsigned long int answer = 2527315200UL; |
| 141 | |
| 142 | struct tm tm; |
| 143 | time_t t; |
| 144 | tm.tm_year = 2050 - 1900; |
| 145 | tm.tm_mon = 2 - 1; |
| 146 | tm.tm_mday = 1; |
| 147 | tm.tm_hour = tm.tm_min = tm.tm_sec = 0; |
| 148 | tm.tm_isdst = -1; |
| 149 | |
| 150 | /* Use the portable POSIX.1 specification "TZ=PST8PDT,M4.1.0,M10.5.0" |
| 151 | instead of "TZ=America/Vancouver" in order to detect the bug even |
| 152 | on systems that don't support the Olson extension, or don't have the |
| 153 | full zoneinfo tables installed. */ |
| 154 | putenv ("TZ=PST8PDT,M4.1.0,M10.5.0"); |
| 155 | |
| 156 | t = mktime (&tm); |
| 157 | |
| 158 | /* Check that the result is either a failure, or close enough |
| 159 | to the correct answer that we can assume the discrepancy is |
| 160 | due to leap seconds. */ |
| 161 | return (t == (time_t) -1 |
| 162 | || (0 < t && answer - 120 <= t && t <= answer + 120)); |
| 163 | } |
| 164 | |
| 165 | int |
| 166 | main () |
| 167 | { |
| 168 | int result = 0; |
| 169 | time_t t, delta; |
| 170 | int i, j; |
| 171 | int time_t_signed_magnitude = (time_t) ~ (time_t) 0 < (time_t) -1; |
| 172 | int time_t_signed = ! ((time_t) 0 < (time_t) -1); |
| 173 | |
| 174 | #if HAVE_DECL_ALARM |
| 175 | /* This test makes some buggy mktime implementations loop. |
| 176 | Give up after 60 seconds; a mktime slower than that |
| 177 | isn't worth using anyway. */ |
| 178 | signal (SIGALRM, SIG_DFL); |
| 179 | alarm (60); |
| 180 | #endif |
| 181 | |
| 182 | time_t_max = (! time_t_signed |
| 183 | ? (time_t) -1 |
| 184 | : ((((time_t) 1 << (sizeof (time_t) * CHAR_BIT - 2)) - 1) |
| 185 | * 2 + 1)); |
| 186 | time_t_min = (! time_t_signed |
| 187 | ? (time_t) 0 |
| 188 | : time_t_signed_magnitude |
| 189 | ? ~ (time_t) 0 |
| 190 | : ~ time_t_max); |
| 191 | |
| 192 | delta = time_t_max / 997; /* a suitable prime number */ |
| 193 | for (i = 0; i < N_STRINGS; i++) |
| 194 | { |
| 195 | if (tz_strings[i]) |
| 196 | putenv (tz_strings[i]); |
| 197 | |
| 198 | for (t = 0; t <= time_t_max - delta && (result & 1) == 0; t += delta) |
| 199 | if (! mktime_test (t)) |
| 200 | result |= 1; |
| 201 | if ((result & 2) == 0 |
| 202 | && ! (mktime_test ((time_t) 1) |
| 203 | && mktime_test ((time_t) (60 * 60)) |
| 204 | && mktime_test ((time_t) (60 * 60 * 24)))) |
| 205 | result |= 2; |
| 206 | |
| 207 | for (j = 1; (result & 4) == 0; j <<= 1) |
| 208 | { |
| 209 | if (! bigtime_test (j)) |
| 210 | result |= 4; |
| 211 | if (INT_MAX / 2 < j) |
| 212 | break; |
| 213 | } |
| 214 | if ((result & 8) == 0 && ! bigtime_test (INT_MAX)) |
| 215 | result |= 8; |
| 216 | } |
| 217 | if (! irix_6_4_bug ()) |
| 218 | result |= 16; |
| 219 | if (! spring_forward_gap ()) |
| 220 | result |= 32; |
| 221 | if (! year_2050_test ()) |
| 222 | result |= 64; |
| 223 | return result; |
| 224 | }]])], |
| 225 | [gl_cv_func_working_mktime=yes], |
| 226 | [gl_cv_func_working_mktime=no], |
| 227 | [gl_cv_func_working_mktime=no]) |
| 228 | ]) |
| 229 | |
| 230 | if test $gl_cv_func_working_mktime = no; then |
| 231 | REPLACE_MKTIME=1 |
| 232 | else |
| 233 | REPLACE_MKTIME=0 |
| 234 | fi |
| 235 | ]) |
| 236 | |
| 237 | AC_DEFUN([gl_FUNC_MKTIME_INTERNAL], [ |
| 238 | AC_REQUIRE([gl_FUNC_MKTIME]) |
| 239 | if test $REPLACE_MKTIME = 0; then |
| 240 | dnl BeOS has __mktime_internal in libc, but other platforms don't. |
| 241 | AC_CHECK_FUNC([__mktime_internal], |
| 242 | [AC_DEFINE([mktime_internal], [__mktime_internal], |
| 243 | [Define to the real name of the mktime_internal function.]) |
| 244 | ], |
| 245 | [dnl mktime works but it doesn't export __mktime_internal, |
| 246 | dnl so we need to substitute our own mktime implementation. |
| 247 | REPLACE_MKTIME=1 |
| 248 | ]) |
| 249 | fi |
| 250 | ]) |
| 251 | |
| 252 | # Prerequisites of lib/mktime.c. |
| 253 | AC_DEFUN([gl_PREREQ_MKTIME], [:]) |