lnav/m4/ax_check_pcre2.m4
AJ Bagwell c431ba904c [pcre2] don't add PRCE2_HOME to the search path if it is empty
This used to add -L/lib to LDFLAGS which was not an issue unless
you are cross compiling and then it may detect PCRE features based
on the host PCRE not the target one.
2022-11-29 11:07:32 +00:00

166 lines
6.6 KiB
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# ===========================================================================
# https://www.gnu.org/software/autoconf-archive/ax_check_pcre2.html
# ===========================================================================
#
# SYNOPSIS
#
# AX_CHECK_PCRE2([bits], [action-if-found], [action-if-not-found])
#
# DESCRIPTION
#
# Search for an installed libpcre2-8 library. If nothing was specified
# when calling configure, it searches first in /usr/local and then in
# /usr, /opt/local and /sw. If the --with-pcre2=DIR is specified, it will
# try to find it in DIR/include/pcre2.h and DIR/lib/libpcre2-8. If
# --without-pcre2 is specified, the library is not searched at all.
#
# If 'bits' is empty or '8', PCRE2 8-bit character support is checked
# only. If 'bits' contains '16', PCRE2 8-bit and 16-bit character support
# are checked. If 'bits' contains '32', PCRE2 8-bit and 32-bit character
# support are checked. When 'bits' contains both '16' and '32', PCRE2
# 8-bit, 16-bit, and 32-bit character support is checked.
#
# If either the header file (pcre2.h), or the library (libpcre2-8) is not
# found, or the specified PCRE2 character bit width is not supported,
# shell commands 'action-if-not-found' is run. If 'action-if-not-found' is
# not specified, the configuration exits on error, asking for a valid
# PCRE2 installation directory or --without-pcre2.
#
# If both header file and library are found, and the specified PCRE2 bit
# widths are supported, shell commands 'action-if-found' is run. If
# 'action-if-found' is not specified, the default action appends
# '-I${PCRE2_HOME}/include' to CPFLAGS, appends '-L$PCRE2_HOME}/lib' to
# LDFLAGS, prepends '-lpcre2-8' to LIBS, and calls AC_DEFINE(HAVE_PCRE2).
# You should use autoheader to include a definition for this symbol in a
# config.h file. Sample usage in a C/C++ source is as follows:
#
# #ifdef HAVE_PCRE2
# #define PCRE2_CODE_UNIT_WIDTH 8
# #include <pcre2.h>
# #endif /* HAVE_PCRE2 */
#
# LICENSE
#
# Copyright (c) 2020 Robert van Engelen <engelen@acm.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 2 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 2
AC_DEFUN([AX_CHECK_PCRE2],
#
# Handle user hints
#
[AC_MSG_CHECKING(if PCRE2 is wanted)
pcre2_places="/usr/local /usr /opt/local /sw"
AC_ARG_WITH([pcre2],
[ --with-pcre2=DIR root directory path of PCRE2 installation @<:@defaults to
/usr/local or /usr if not found in /usr/local@:>@
--without-pcre2 to disable PCRE2 usage completely],
[if test "$withval" != "no" ; then
AC_MSG_RESULT(yes)
if test -d "$withval"
then
pcre2_places="$withval $pcre2_places"
else
AC_MSG_WARN([Sorry, $withval does not exist, checking usual places])
fi
else
pcre2_places=""
AC_MSG_RESULT(no)
fi],
[AC_MSG_RESULT(yes)])
#
# Locate PCRE2, if wanted
#
if test -n "${pcre2_places}"
then
# check the user supplied or any other more or less 'standard' place:
# Most UNIX systems : /usr/local and /usr
# MacPorts / Fink on OSX : /opt/local respectively /sw
for PCRE2_HOME in ${pcre2_places} ; do
if test -f "${PCRE2_HOME}/include/pcre2.h"; then break; fi
PCRE2_HOME=""
done
PCRE2_OLD_LDFLAGS=$LDFLAGS
PCRE2_OLD_CPPFLAGS=$CPPFLAGS
if test -n "${PCRE2_HOME}"; then
LDFLAGS="$LDFLAGS -L${PCRE2_HOME}/lib"
CPPFLAGS="$CPPFLAGS -I${PCRE2_HOME}/include"
fi
AC_LANG_PUSH([C])
AC_CHECK_LIB([pcre2-8], [pcre2_compile_8], [pcre2_cv_libpcre2=yes], [pcre2_cv_libpcre2=no])
AC_CHECK_HEADER([pcre2.h], [pcre2_cv_pcre2_h=yes], [pcre2_cv_pcre2_h=no], [#define PCRE2_CODE_UNIT_WIDTH 8])
case "$1" in
*16*)
AC_CHECK_LIB([pcre2-16], [pcre2_compile_16], [pcre2_cv_libpcre2_16=yes], [pcre2_cv_libpcre2_16=no])
AC_CHECK_HEADER([pcre2.h], [pcre2_cv_pcre2_16_h=yes], [pcre2_cv_pcre2_16_h=no], [#define PCRE2_CODE_UNIT_WIDTH 16])
if test "$pcre2_cv_libpcre2_16" = "no" || test "$pcre2_cv_pcre2_16_h" = "no"; then
pcre2_cv_libpcre2=no
fi
;;
esac
case "$1" in
*32*)
AC_CHECK_LIB([pcre2-32], [pcre2_compile_32], [pcre2_cv_libpcre2_32=yes], [pcre2_cv_libpcre2_32=no])
AC_CHECK_HEADER([pcre2.h], [pcre2_cv_pcre2_32_h=yes], [pcre2_cv_pcre2_32_h=no], [#define PCRE2_CODE_UNIT_WIDTH 32])
if test "$pcre2_cv_libpcre2_32" = "no" || test "$pcre2_cv_pcre2_32_h" = "no"; then
pcre2_cv_libpcre2=no
fi
esac
AC_LANG_POP([C])
if test "$pcre2_cv_libpcre2" = "yes" && test "$pcre2_cv_pcre2_h" = "yes"
then
#
# If both library and header were found, action-if-found
#
m4_ifblank([$2],[
if test -n "${PCRE2_HOME}"; then
CPPFLAGS="$CPPFLAGS -I${PCRE2_HOME}/include"
LDFLAGS="$LDFLAGS -L${PCRE2_HOME}/lib"
fi
LIBS="-lpcre2-8 $LIBS"
AC_DEFINE([HAVE_PCRE2], [1],
[Define to 1 if you have `PCRE2' library (-lpcre2-$1)])
],[
# Restore variables
LDFLAGS="$PCRE2_OLD_LDFLAGS"
CPPFLAGS="$PCRE2_OLD_CPPFLAGS"
$2
])
else
#
# If either header or library was not found, action-if-not-found
#
m4_default([$3],[
AC_MSG_ERROR([either specify a valid PCRE2 installation with --with-pcre2=DIR or disable PCRE2 usage with --without-pcre2])
])
fi
fi
])