# pkg.m4 - Macros to locate and utilise pkg-config.            -*- Autoconf -*-
 # serial 1 (pkg-config-0.24)
 # 
 # Copyright © 2004 Scott James Remnant <scott@netsplit.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 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, write to the Free Software
 # Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 #
 # As a special exception to the GNU General Public License, if you
 # distribute this file as part of a program that contains a
 # configuration script generated by Autoconf, you may include it under
 # the same distribution terms that you use for the rest of that program.
 
 # PKG_PROG_PKG_CONFIG([MIN-VERSION])
 # ----------------------------------
 AC_DEFUN([PKG_PROG_PKG_CONFIG],
 [m4_pattern_forbid([^_?PKG_[A-Z_]+$])
 m4_pattern_allow([^PKG_CONFIG(_(PATH|LIBDIR|SYSROOT_DIR|ALLOW_SYSTEM_(CFLAGS|LIBS)))?$])
 m4_pattern_allow([^PKG_CONFIG_(DISABLE_UNINSTALLED|TOP_BUILD_DIR|DEBUG_SPEW)$])
 AC_ARG_VAR([PKG_CONFIG], [path to pkg-config utility])
 AC_ARG_VAR([PKG_CONFIG_PATH], [directories to add to pkg-config's search path])
 AC_ARG_VAR([PKG_CONFIG_LIBDIR], [path overriding pkg-config's built-in search path])
 
 if test "x$ac_cv_env_PKG_CONFIG_set" != "xset"; then
 	AC_PATH_TOOL([PKG_CONFIG], [pkg-config])
 fi
 if test -n "$PKG_CONFIG"; then
 	_pkg_min_version=m4_default([$1], [0.9.0])
 	AC_MSG_CHECKING([pkg-config is at least version $_pkg_min_version])
 	if $PKG_CONFIG --atleast-pkgconfig-version $_pkg_min_version; then
 		AC_MSG_RESULT([yes])
 	else
 		AC_MSG_RESULT([no])
 		PKG_CONFIG=""
 	fi
 fi[]dnl
 ])# PKG_PROG_PKG_CONFIG
 
 # PKG_CHECK_EXISTS(MODULES, [ACTION-IF-FOUND], [ACTION-IF-NOT-FOUND])
 #
 # Check to see whether a particular set of modules exists.  Similar
 # to PKG_CHECK_MODULES(), but does not set variables or print errors.
 #
 # Please remember that m4 expands AC_REQUIRE([PKG_PROG_PKG_CONFIG])
 # only at the first occurence in configure.ac, so if the first place
 # it's called might be skipped (such as if it is within an "if", you
 # have to call PKG_CHECK_EXISTS manually
 # --------------------------------------------------------------
 AC_DEFUN([PKG_CHECK_EXISTS],
 [AC_REQUIRE([PKG_PROG_PKG_CONFIG])dnl
 if test -n "$PKG_CONFIG" && \
     AC_RUN_LOG([$PKG_CONFIG --exists --print-errors "$1"]); then
   m4_default([$2], [:])
 m4_ifvaln([$3], [else
   $3])dnl
 fi])
 
 # _PKG_CONFIG([VARIABLE], [COMMAND], [MODULES])
 # ---------------------------------------------
 m4_define([_PKG_CONFIG],
 [if test -n "$$1"; then
     pkg_cv_[]$1="$$1"
  elif test -n "$PKG_CONFIG"; then
     PKG_CHECK_EXISTS([$3],
                      [pkg_cv_[]$1=`$PKG_CONFIG --[]$2 "$3" 2>/dev/null`
 		      test "x$?" != "x0" && pkg_failed=yes ],
 		     [pkg_failed=yes])
  else
     pkg_failed=untried
 fi[]dnl
 ])# _PKG_CONFIG
 
 # _PKG_SHORT_ERRORS_SUPPORTED
 # -----------------------------
 AC_DEFUN([_PKG_SHORT_ERRORS_SUPPORTED],
 [AC_REQUIRE([PKG_PROG_PKG_CONFIG])
 if $PKG_CONFIG --atleast-pkgconfig-version 0.20; then
         _pkg_short_errors_supported=yes
 else
         _pkg_short_errors_supported=no
 fi[]dnl
 ])# _PKG_SHORT_ERRORS_SUPPORTED
 
 
 # PKG_CHECK_MODULES(VARIABLE-PREFIX, MODULES, [ACTION-IF-FOUND],
 # [ACTION-IF-NOT-FOUND])
 #
 #
 # Note that if there is a possibility the first call to
 # PKG_CHECK_MODULES might not happen, you should be sure to include an
 # explicit call to PKG_PROG_PKG_CONFIG in your configure.ac
 #
 #
 # --------------------------------------------------------------
 AC_DEFUN([PKG_CHECK_MODULES],
 [AC_REQUIRE([PKG_PROG_PKG_CONFIG])dnl
 AC_ARG_VAR([$1][_CFLAGS], [C compiler flags for $1, overriding pkg-config])dnl
 AC_ARG_VAR([$1][_LIBS], [linker flags for $1, overriding pkg-config])dnl
 
 pkg_failed=no
 AC_MSG_CHECKING([for $1])
 
 _PKG_CONFIG([$1][_CFLAGS], [cflags], [$2])
 _PKG_CONFIG([$1][_LIBS], [libs], [$2])
 
 m4_define([_PKG_TEXT], [Alternatively, you may set the environment variables $1[]_CFLAGS
 and $1[]_LIBS to avoid the need to call pkg-config.
 See the pkg-config man page for more details.])
 
 if test $pkg_failed = yes; then
    	AC_MSG_RESULT([no])
         _PKG_SHORT_ERRORS_SUPPORTED
         if test $_pkg_short_errors_supported = yes; then
 	        $1[]_PKG_ERRORS=`$PKG_CONFIG --short-errors --print-errors --cflags --libs "$2" 2>&1`
         else 
 	        $1[]_PKG_ERRORS=`$PKG_CONFIG --print-errors --cflags --libs "$2" 2>&1`
         fi
 	# Put the nasty error message in config.log where it belongs
 	echo "$$1[]_PKG_ERRORS" >&AS_MESSAGE_LOG_FD
 
 	m4_default([$4], [AC_MSG_ERROR(
 [Package requirements ($2) were not met:
 
 $$1_PKG_ERRORS
 
 Consider adjusting the PKG_CONFIG_PATH environment variable if you
 installed software in a non-standard prefix.
 
 _PKG_TEXT])[]dnl
         ])
 elif test $pkg_failed = untried; then
      	AC_MSG_RESULT([no])
 	m4_default([$4], [AC_MSG_FAILURE(
 [The pkg-config script could not be found or is too old.  Make sure it
 is in your PATH or set the PKG_CONFIG environment variable to the full
 path to pkg-config.
 
 _PKG_TEXT
 
 To get pkg-config, see <http://pkg-config.freedesktop.org/>.])[]dnl
         ])
 else
 	$1[]_CFLAGS=$pkg_cv_[]$1[]_CFLAGS
 	$1[]_LIBS=$pkg_cv_[]$1[]_LIBS
         AC_MSG_RESULT([yes])
 	$3
 fi[]dnl
 ])# PKG_CHECK_MODULES