116 строки
4.2 KiB
Plaintext
116 строки
4.2 KiB
Plaintext
# ============================================================================
|
|
# https://www.gnu.org/software/autoconf-archive/ax_compile_check_sizeof.html
|
|
# ============================================================================
|
|
#
|
|
# SYNOPSIS
|
|
#
|
|
# AX_COMPILE_CHECK_SIZEOF(TYPE [, HEADERS [, EXTRA_SIZES...]])
|
|
#
|
|
# DESCRIPTION
|
|
#
|
|
# This macro checks for the size of TYPE using compile checks, not run
|
|
# checks. You can supply extra HEADERS to look into. the check will cycle
|
|
# through 1 2 4 8 16 and any EXTRA_SIZES the user supplies. If a match is
|
|
# found, it will #define SIZEOF_`TYPE' to that value. Otherwise it will
|
|
# emit a configure time error indicating the size of the type could not be
|
|
# determined.
|
|
#
|
|
# The trick is that C will not allow duplicate case labels. While this is
|
|
# valid C code:
|
|
#
|
|
# switch (0) case 0: case 1:;
|
|
#
|
|
# The following is not:
|
|
#
|
|
# switch (0) case 0: case 0:;
|
|
#
|
|
# Thus, the AC_TRY_COMPILE will fail if the currently tried size does not
|
|
# match.
|
|
#
|
|
# Here is an example skeleton configure.in script, demonstrating the
|
|
# macro's usage:
|
|
#
|
|
# AC_PROG_CC
|
|
# AC_CHECK_HEADERS(stddef.h unistd.h)
|
|
# AC_TYPE_SIZE_T
|
|
# AC_CHECK_TYPE(ssize_t, int)
|
|
#
|
|
# headers='#ifdef HAVE_STDDEF_H
|
|
# #include <stddef.h>
|
|
# #endif
|
|
# #ifdef HAVE_UNISTD_H
|
|
# #include <unistd.h>
|
|
# #endif
|
|
# '
|
|
#
|
|
# AX_COMPILE_CHECK_SIZEOF(char)
|
|
# AX_COMPILE_CHECK_SIZEOF(short)
|
|
# AX_COMPILE_CHECK_SIZEOF(int)
|
|
# AX_COMPILE_CHECK_SIZEOF(long)
|
|
# AX_COMPILE_CHECK_SIZEOF(unsigned char *)
|
|
# AX_COMPILE_CHECK_SIZEOF(void *)
|
|
# AX_COMPILE_CHECK_SIZEOF(size_t, $headers)
|
|
# AX_COMPILE_CHECK_SIZEOF(ssize_t, $headers)
|
|
# AX_COMPILE_CHECK_SIZEOF(ptrdiff_t, $headers)
|
|
# AX_COMPILE_CHECK_SIZEOF(off_t, $headers)
|
|
#
|
|
# LICENSE
|
|
#
|
|
# Copyright (c) 2008 Kaveh Ghazi <ghazi@caip.rutgers.edu>
|
|
# Copyright (c) 2017 Reini Urban <rurban@cpan.org>
|
|
#
|
|
# 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.
|
|
#
|
|
# You should have received a copy of the GNU General Public License along
|
|
# with this program. If not, see <https://www.gnu.org/licenses/>.
|
|
#
|
|
# As a special exception, the respective Autoconf Macro's copyright owner
|
|
# gives unlimited permission to copy, distribute and modify the configure
|
|
# scripts that are the output of Autoconf when processing the Macro. You
|
|
# need not follow the terms of the GNU General Public License when using
|
|
# or distributing such scripts, even though portions of the text of the
|
|
# Macro appear in them. The GNU General Public License (GPL) does govern
|
|
# all other use of the material that constitutes the Autoconf Macro.
|
|
#
|
|
# This special exception to the GPL applies to versions of the Autoconf
|
|
# Macro released by the Autoconf Archive. When you make and distribute a
|
|
# modified version of the Autoconf Macro, you may extend this special
|
|
# exception to the GPL to apply to your modified version as well.
|
|
|
|
#serial 7
|
|
|
|
AU_ALIAS([AC_COMPILE_CHECK_SIZEOF], [AX_COMPILE_CHECK_SIZEOF])
|
|
AC_DEFUN([AX_COMPILE_CHECK_SIZEOF],
|
|
[changequote(<<, >>)dnl
|
|
dnl The name to #define.
|
|
define(<<AC_TYPE_NAME>>, translit(sizeof_$1, [a-z *], [A-Z_P]))dnl
|
|
dnl The cache variable name.
|
|
define(<<AC_CV_NAME>>, translit(ac_cv_sizeof_$1, [ *], [_p]))dnl
|
|
changequote([, ])dnl
|
|
AC_MSG_CHECKING(size of $1)
|
|
AC_CACHE_VAL(AC_CV_NAME,
|
|
[for ac_size in 4 8 1 2 16 $3 ; do # List sizes in rough order of prevalence.
|
|
AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
|
|
#include <sys/types.h>
|
|
$2
|
|
]], [[switch (0) case 0: case (sizeof ($1) == $ac_size):;]])], [AC_CV_NAME=$ac_size])
|
|
if test x$AC_CV_NAME != x ; then break; fi
|
|
done
|
|
])
|
|
if test x$AC_CV_NAME = x ; then
|
|
AC_MSG_ERROR([cannot determine a size for $1])
|
|
fi
|
|
AC_MSG_RESULT($AC_CV_NAME)
|
|
AC_DEFINE_UNQUOTED(AC_TYPE_NAME, $AC_CV_NAME, [The number of bytes in type $1])
|
|
undefine([AC_TYPE_NAME])dnl
|
|
undefine([AC_CV_NAME])dnl
|
|
])
|