--- /dev/null
+# This file is part of Autoconf. -*- Autoconf -*-
+# Macros that test for specific, unclassified, features.
+#
+# Copyright (C) 1992-1996, 1998-2017, 2020-2023 Free Software
+# Foundation, Inc.
+
+# This file is part of Autoconf. This program is free
+# software; you can redistribute it and/or modify it under the
+# terms of the GNU General Public License as published by the
+# Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# Under Section 7 of GPL version 3, you are granted additional
+# permissions described in the Autoconf Configure Script Exception,
+# version 3.0, as published by the Free Software Foundation.
+#
+# You should have received a copy of the GNU General Public License
+# and a copy of the Autoconf Configure Script Exception along with
+# this program; see the files COPYINGv3 and COPYING.EXCEPTION
+# respectively. If not, see <https://www.gnu.org/licenses/>.
+
+# Written by David MacKenzie, with help from
+# François Pinard, Karl Berry, Richard Pixley, Ian Lance Taylor,
+# Roland McGrath, Noah Friedman, david d zuhn, and many others.
+# _AC_SYS_YEAR2038_TEST_CODE
+# --------------------------
+# C code used to probe for time_t that can represent time points more
+# than 2**31 - 1 seconds after the epoch. With the usual Unix epoch,
+# these correspond to dates after 2038-01-18 22:14:07 +0000 (Gregorian),
+# hence the name.
+
+AC_DEFUN([_AC_SYS_YEAR2038_TEST_CODE],
+[[
+ #include <time.h>
+ /* Check that time_t can represent 2**32 - 1 correctly. */
+ #define LARGE_TIME_T \\
+ ((time_t) (((time_t) 1 << 30) - 1 + 3 * ((time_t) 1 << 30)))
+ int verify_time_t_range[(LARGE_TIME_T / 65537 == 65535
+ && LARGE_TIME_T % 65537 == 0)
+ ? 1 : -1];
+]])
+
+# _AC_SYS_YEAR2038_OPTIONS
+# ------------------------
+# List of known ways to enable support for large time_t. If you change
+# this list you probably also need to change the AS_CASE at the end of
+# _AC_SYS_YEAR2038_PROBE.
+m4_define([_AC_SYS_YEAR2038_OPTIONS], m4_normalize(
+ ["none needed"] dnl 64-bit and newer 32-bit Unix
+ ["-D_TIME_BITS=64"] dnl glibc 2.34 with some 32-bit ABIs
+ ["-D__MINGW_USE_VC2005_COMPAT"] dnl 32-bit MinGW
+ ["-U_USE_32_BIT_TIME_T -D__MINGW_USE_VC2005_COMPAT"]
+ dnl 32-bit MinGW (misconfiguration)
+))
+
+# _AC_SYS_YEAR2038_PROBE
+# ----------------------
+# Subroutine of AC_SYS_YEAR2038. Probe for time_t that can represent
+# time points more than 2**31 - 1 seconds after the epoch (dates after
+# 2038-01-18, see above) and set the cache variable ac_cv_sys_year2038_opts
+# to one of the values in the _AC_SYS_YEAR2038_OPTIONS list, or to
+# "support not detected" if none of them worked. Then, set compilation
+# options and #defines as necessary to enable large time_t support.
+#
+# Note that we do not test whether mktime, localtime, etc. handle
+# large values of time_t correctly, as that would require use of
+# AC_TRY_RUN. Note also that some systems only support large time_t
+# together with large off_t.
+#
+# If you change this macro you may also need to change
+# _AC_SYS_YEAR2038_OPTIONS.
+AC_DEFUN([_AC_SYS_YEAR2038_PROBE],
+[AC_CACHE_CHECK([for $CC option for timestamps after 2038],
+ [ac_cv_sys_year2038_opts],
+ [ac_save_CPPFLAGS="$CPPFLAGS"
+ ac_opt_found=no
+ for ac_opt in _AC_SYS_YEAR2038_OPTIONS; do
+ AS_IF([test x"$ac_opt" != x"none needed"],
+ [CPPFLAGS="$ac_save_CPPFLAGS $ac_opt"])
+ AC_COMPILE_IFELSE([AC_LANG_PROGRAM([_AC_SYS_YEAR2038_TEST_CODE])],
+ [ac_cv_sys_year2038_opts="$ac_opt"
+ ac_opt_found=yes])
+ test $ac_opt_found = no || break
+ done
+ CPPFLAGS="$ac_save_CPPFLAGS"
+ test $ac_opt_found = yes || ac_cv_sys_year2038_opts="support not detected"])
+
+ac_have_year2038=yes
+AS_CASE([$ac_cv_sys_year2038_opts],
+ ["none needed"], [],
+ ["support not detected"],
+ [ac_have_year2038=no],
+
+ ["-D_TIME_BITS=64"],
+ [AC_DEFINE([_TIME_BITS], [64],
+ [Number of bits in time_t, on hosts where this is settable.])],
+
+ ["-D__MINGW_USE_VC2005_COMPAT"],
+ [AC_DEFINE([__MINGW_USE_VC2005_COMPAT], [1],
+ [Define to 1 on platforms where this makes time_t a 64-bit type.])],
+
+ ["-U_USE_32_BIT_TIME_T"*],
+ [AC_MSG_FAILURE(m4_text_wrap(
+ [the 'time_t' type is currently forced to be 32-bit.
+ It will stop working after mid-January 2038.
+ Remove _USE_32BIT_TIME_T from the compiler flags.],
+ [], [], [55]))],
+
+ [AC_MSG_ERROR(
+ [internal error: bad value for \$ac_cv_sys_year2038_opts])])
+])
+
+# _AC_SYS_YEAR2038_ENABLE
+# -----------------------
+# Depending on which of the YEAR2038 macros was used, add either an
+# --enable-year2038 or a --disable-year2038 to
+# the configure script. This is expanded very late and
+# therefore there cannot be any code in the AC_ARG_ENABLE. The
+# default value for 'enable_year2038' is emitted unconditionally
+# because the generated code always looks at this variable.
+m4_define([_AC_SYS_YEAR2038_ENABLE],
+[m4_divert_text([DEFAULTS],
+ m4_provide_if([AC_SYS_YEAR2038],
+ [enable_year2038=yes],
+ [enable_year2038=no]))]dnl
+[AC_ARG_ENABLE([year2038],
+ m4_provide_if([AC_SYS_YEAR2038],
+ [AS_HELP_STRING([--disable-year2038],
+ [don't support timestamps after 2038])],
+ [AS_HELP_STRING([--enable-year2038],
+ [support timestamps after 2038])]))])
+
+# AC_SYS_YEAR2038
+# ---------------
+# Attempt to detect and activate support for large time_t.
+# On systems where time_t is not always 64 bits, this probe can be
+# skipped by passing the --disable-year2038 option to configure.
+AC_DEFUN([AC_SYS_YEAR2038],
+[AC_REQUIRE([AC_SYS_LARGEFILE])dnl
+AS_IF([test "$enable_year2038,$ac_have_year2038,$cross_compiling" = yes,no,no],
+ [# If we're not cross compiling and 'touch' works with a large
+ # timestamp, then we can presume the system supports wider time_t
+ # *somehow* and we just weren't able to detect it. One common
+ # case that we deliberately *don't* probe for is a system that
+ # supports both 32- and 64-bit ABIs but only the 64-bit ABI offers
+ # wide time_t. (It would be inappropriate for us to override an
+ # intentional use of -m32.) Error out, demanding use of
+ # --disable-year2038 if this is intentional.
+ AS_IF([TZ=UTC0 touch -t 210602070628.15 conftest.time 2>/dev/null],
+ [AS_CASE([`TZ=UTC0 LC_ALL=C ls -l conftest.time 2>/dev/null`],
+ [*'Feb 7 2106'* | *'Feb 7 17:10'*],
+ [AC_MSG_FAILURE(m4_text_wrap(
+ [this system appears to support timestamps after mid-January 2038,
+ but no mechanism for enabling wide 'time_t' was detected.
+ Did you mean to build a 64-bit binary? (E.g., 'CC="${CC} -m64"'.)
+ To proceed with 32-bit time_t, configure with '--disable-year2038'.],
+ [], [], [55]))])])])])
+
+# AC_SYS_YEAR2038_RECOMMENDED
+# ---------------------------
+# Same as AC_SYS_YEAR2038, but recommend support for large time_t.
+# If we cannot find any way to make time_t capable of representing
+# values larger than 2**31 - 1, error out unless --disable-year2038 is given.
+AC_DEFUN([AC_SYS_YEAR2038_RECOMMENDED],
+[AC_REQUIRE([AC_SYS_YEAR2038])dnl
+AS_IF([test "$enable_year2038,$ac_have_year2038" = yes,no],
+ [AC_MSG_FAILURE(m4_text_wrap(
+ [could not enable timestamps after mid-January 2038.
+ This package recommends support for these later timestamps.
+ However, to proceed with signed 32-bit time_t even though it
+ will fail then, configure with '--disable-year2038'.],
+ [], [], [55]))])])
+
+AC_DEFUN([UL_YEAR2038_INIT],[
+ AS_IF([test "$enable_year2038" != no],
+ [_AC_SYS_YEAR2038_PROBE])
+ AC_CONFIG_COMMANDS_PRE([_AC_SYS_YEAR2038_ENABLE])])
projects / thirdparty / util-linux.git / commitdiff
