OVMS3/OVMS.V3/components/wolfssh/m4/ax_check_library.m4

95 lines
3.7 KiB
Text

# ===========================================================================
# https://www.gnu.org/software/autoconf-archive/ax_check_library.html
# ===========================================================================
#
# SYNOPSIS
#
# AX_CHECK_LIBRARY(VARIABLE-PREFIX, HEADER-FILE, LIBRARY-FILE,
# [ACTION-IF-FOUND], [ACTION-IF-NOT_FOUND])
#
# DESCRIPTION
#
# Provides a generic test for a given library, similar in concept to the
# PKG_CHECK_MODULES macro used by pkg-config.
#
# Most simplest libraries can be checked against simply through the
# presence of a header file and a library to link to. This macro allows to
# wrap around the test so that it doesn't have to be recreated each time.
#
# Rather than define --with-$LIBRARY arguments, it uses variables in the
# same way that PKG_CHECK_MODULES does. It doesn't, though, use the same
# names, since you shouldn't provide a value for LIBS or CFLAGS but rather
# for LDFLAGS and CPPFLAGS, to tell the linker and compiler where to find
# libraries and headers respectively.
#
# If the library is find, HAVE_PREFIX is defined, and in all cases
# PREFIX_LDFLAGS and PREFIX_CPPFLAGS are substituted.
#
# Example:
#
# AX_CHECK_LIBRARY([LIBEVENT], [event.h], [event], [],
# [AC_MSG_ERROR([Unable to find libevent])])
#
# LICENSE
#
# Copyright (c) 2010 Diego Elio Petteno` <flameeyes@gmail.com>
#
# 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 5
AC_DEFUN([AX_CHECK_LIBRARY], [
AC_ARG_VAR($1[_CPPFLAGS], [C preprocessor flags for ]$1[ headers])
AC_ARG_VAR($1[_LDFLAGS], [linker flags for ]$1[ libraries])
AC_CACHE_VAL(AS_TR_SH([ax_cv_have_]$1),
[save_CPPFLAGS="$CPPFLAGS"
save_LDFLAGS="$LDFLAGS"
save_LIBS="$LIBS"
AS_IF([test "x$]$1[_CPPFLAGS" != "x"],
[CPPFLAGS="$CPPFLAGS $]$1[_CPPFLAGS"])
AS_IF([test "x$]$1[_LDFLAGS" != "x"],
[LDFLAGS="$LDFLAGS $]$1[_LDFLAGS"])
AC_CHECK_HEADER($2, [
AC_CHECK_LIB($3, [main],
[AS_TR_SH([ax_cv_have_]$1)=yes],
[AS_TR_SH([ax_cv_have_]$1)=no])
], [AS_TR_SH([ax_cv_have_]$1)=no])
CPPFLAGS="$save_CPPFLAGS"
LDFLAGS="$save_LDFLAGS"
LIBS="$save_LIBS"
])
AS_IF([test "$]AS_TR_SH([ax_cv_have_]$1)[" = "yes"],
AC_DEFINE([HAVE_]$1, [1], [Define to 1 if ]$1[ is found])
[$4],
[$5])
])