test for boost from the autoconf archive.

It is modified such that the presence of boost is not mandatory.

[[Imported from SVN: r6081]]

m4/ax_boost_base.m4

+# ===========================================================================
+#             http://autoconf-archive.cryp.to/ax_boost_base.html
+# ===========================================================================
+#
+# SYNOPSIS
+#
+#   AX_BOOST_BASE([MINIMUM-VERSION])
+#
+# DESCRIPTION
+#
+#   Test for the Boost C++ libraries of a particular version (or newer)
+#
+#   If no path to the installed boost library is given the macro searchs
+#   under /usr, /usr/local, /opt and /opt/local and evaluates the
+#   $BOOST_ROOT environment variable. Further documentation is available at
+#   <http://randspringer.de/boost/index.html>.
+#
+#   This macro calls:
+#
+#     AC_SUBST(BOOST_CPPFLAGS) / AC_SUBST(BOOST_LDFLAGS)
+#
+#   And sets:
+#
+#     HAVE_BOOST
+#
+# LICENSE
+#
+#   Copyright (c) 2008 Thomas Porschberg <thomas@randspringer.de>
+#
+#   Copying and distribution of this file, with or without modification, are
+#   permitted in any medium without royalty provided the copyright notice
+#   and this notice are preserved.
+
+AC_DEFUN([AX_BOOST_BASE],
+[
+AC_ARG_WITH([boost],
+	AS_HELP_STRING([--with-boost@<:@=DIR@:>@], [use boost (default is yes) - it is possible to specify the root directory for boost (optional)]),
+	[
+    if test "$withval" = "no"; then
+		want_boost="no"
+    elif test "$withval" = "yes"; then
+        want_boost="yes"
+        ac_boost_path=""
+    else
+	    want_boost="yes"
+        ac_boost_path="$withval"
+	fi
+    ],
+    [want_boost="yes"])
+
+
+AC_ARG_WITH([boost-libdir],
+        AS_HELP_STRING([--with-boost-libdir=LIB_DIR],
+        [Force given directory for boost libraries. Note that this will overwrite library path detection, so use this parameter only if default library detection fails and you know exactly where your boost libraries are located.]),
+        [
+        if test -d $withval
+        then
+                ac_boost_lib_path="$withval"
+        else
+                AC_MSG_ERROR(--with-boost-libdir expected directory name)
+        fi
+        ],
+        [ac_boost_lib_path=""]
+)
+
+if test "x$want_boost" = "xyes"; then
+	boost_lib_version_req=ifelse([$1], ,1.20.0,$1)
+	boost_lib_version_req_shorten=`expr $boost_lib_version_req : '\([[0-9]]*\.[[0-9]]*\)'`
+	boost_lib_version_req_major=`expr $boost_lib_version_req : '\([[0-9]]*\)'`
+	boost_lib_version_req_minor=`expr $boost_lib_version_req : '[[0-9]]*\.\([[0-9]]*\)'`
+	boost_lib_version_req_sub_minor=`expr $boost_lib_version_req : '[[0-9]]*\.[[0-9]]*\.\([[0-9]]*\)'`
+	if test "x$boost_lib_version_req_sub_minor" = "x" ; then
+		boost_lib_version_req_sub_minor="0"
+    	fi
+	WANT_BOOST_VERSION=`expr $boost_lib_version_req_major \* 100000 \+  $boost_lib_version_req_minor \* 100 \+ $boost_lib_version_req_sub_minor`
+	AC_MSG_CHECKING(for boostlib >= $boost_lib_version_req)
+	succeeded=no
+
+	dnl first we check the system location for boost libraries
+	dnl this location ist chosen if boost libraries are installed with the --layout=system option
+	dnl or if you install boost with RPM
+	if test "$ac_boost_path" != ""; then
+		BOOST_LDFLAGS="-L$ac_boost_path/lib"
+		BOOST_CPPFLAGS="-I$ac_boost_path/include"
+	else
+		for ac_boost_path_tmp in /usr /usr/local /opt /opt/local ; do
+			if test -d "$ac_boost_path_tmp/include/boost" && test -r "$ac_boost_path_tmp/include/boost"; then
+				BOOST_LDFLAGS="-L$ac_boost_path_tmp/lib"
+				BOOST_CPPFLAGS="-I$ac_boost_path_tmp/include"
+				break;
+			fi
+		done
+	fi
+
+    dnl overwrite ld flags if we have required special directory with
+    dnl --with-boost-libdir parameter
+    if test "$ac_boost_lib_path" != ""; then
+       BOOST_LDFLAGS="-L$ac_boost_lib_path"
+    fi
+
+	CPPFLAGS_SAVED="$CPPFLAGS"
+	CPPFLAGS="$CPPFLAGS $BOOST_CPPFLAGS"
+	export CPPFLAGS
+
+	LDFLAGS_SAVED="$LDFLAGS"
+	LDFLAGS="$LDFLAGS $BOOST_LDFLAGS"
+	export LDFLAGS
+
+	AC_LANG_PUSH(C++)
+     	AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
+	@%:@include <boost/version.hpp>
+	]], [[
+	#if BOOST_VERSION >= $WANT_BOOST_VERSION
+	// Everything is okay
+	#else
+	#  error Boost version is too old
+	#endif
+	]])],[
+        AC_MSG_RESULT(yes)
+	succeeded=yes
+	found_system=yes
+       	],[
+       	])
+	AC_LANG_POP([C++])
+
+
+
+	dnl if we found no boost with system layout we search for boost libraries
+	dnl built and installed without the --layout=system option or for a staged(not installed) version
+	if test "x$succeeded" != "xyes"; then
+		_version=0
+		if test "$ac_boost_path" != ""; then
+			if test -d "$ac_boost_path" && test -r "$ac_boost_path"; then
+				for i in `ls -d $ac_boost_path/include/boost-* 2>/dev/null`; do
+					_version_tmp=`echo $i | sed "s#$ac_boost_path##" | sed 's/\/include\/boost-//' | sed 's/_/./'`
+					V_CHECK=`expr $_version_tmp \> $_version`
+					if test "$V_CHECK" = "1" ; then
+						_version=$_version_tmp
+					fi
+					VERSION_UNDERSCORE=`echo $_version | sed 's/\./_/'`
+					BOOST_CPPFLAGS="-I$ac_boost_path/include/boost-$VERSION_UNDERSCORE"
+				done
+			fi
+		else
+			for ac_boost_path in /usr /usr/local /opt /opt/local ; do
+				if test -d "$ac_boost_path" && test -r "$ac_boost_path"; then
+					for i in `ls -d $ac_boost_path/include/boost-* 2>/dev/null`; do
+						_version_tmp=`echo $i | sed "s#$ac_boost_path##" | sed 's/\/include\/boost-//' | sed 's/_/./'`
+						V_CHECK=`expr $_version_tmp \> $_version`
+						if test "$V_CHECK" = "1" ; then
+							_version=$_version_tmp
+	               					best_path=$ac_boost_path
+						fi
+					done
+				fi
+			done
+
+			VERSION_UNDERSCORE=`echo $_version | sed 's/\./_/'`
+			BOOST_CPPFLAGS="-I$best_path/include/boost-$VERSION_UNDERSCORE"
+            if test "$ac_boost_lib_path" = ""
+            then
+               BOOST_LDFLAGS="-L$best_path/lib"
+            fi
+
+	    		if test "x$BOOST_ROOT" != "x"; then
+				if test -d "$BOOST_ROOT" && test -r "$BOOST_ROOT" && test -d "$BOOST_ROOT/stage/lib" && test -r "$BOOST_ROOT/stage/lib"; then
+					version_dir=`expr //$BOOST_ROOT : '.*/\(.*\)'`
+					stage_version=`echo $version_dir | sed 's/boost_//' | sed 's/_/./g'`
+			        	stage_version_shorten=`expr $stage_version : '\([[0-9]]*\.[[0-9]]*\)'`
+					V_CHECK=`expr $stage_version_shorten \>\= $_version`
+                    if test "$V_CHECK" = "1" -a "$ac_boost_lib_path" = "" ; then
+						AC_MSG_NOTICE(We will use a staged boost library from $BOOST_ROOT)
+						BOOST_CPPFLAGS="-I$BOOST_ROOT"
+						BOOST_LDFLAGS="-L$BOOST_ROOT/stage/lib"
+					fi
+				fi
+	    		fi
+		fi
+
+		CPPFLAGS="$CPPFLAGS $BOOST_CPPFLAGS"
+		export CPPFLAGS
+		LDFLAGS="$LDFLAGS $BOOST_LDFLAGS"
+		export LDFLAGS
+
+		AC_LANG_PUSH(C++)
+	     	AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
+		@%:@include <boost/version.hpp>
+		]], [[
+		#if BOOST_VERSION >= $WANT_BOOST_VERSION
+		// Everything is okay
+		#else
+		#  error Boost version is too old
+		#endif
+		]])],[
+        	AC_MSG_RESULT(yes)
+		succeeded=yes
+		found_system=yes
+       		],[
+	       	])
+		AC_LANG_POP([C++])
+	fi
+
+	if test "$succeeded" != "yes" ; then
+		if test "$_version" = "0" ; then
+			AC_MSG_NOTICE([[We could not detect the boost libraries (version $boost_lib_version_req_shorten or higher). If you have a staged boost library (still not installed) please specify \$BOOST_ROOT in your environment and do not give a PATH to --with-boost option.  If you are sure you have boost installed, then check your version number looking in <boost/version.hpp>. See http://randspringer.de/boost for more documentation.]])
+		else
+			AC_MSG_NOTICE([Your boost libraries seems to old (version $_version).])
+		fi
+	else
+		AC_SUBST(BOOST_CPPFLAGS)
+		AC_SUBST(BOOST_LDFLAGS)
+		AC_DEFINE(HAVE_BOOST,,[define if the Boost library is available])
+	fi
+
+        CPPFLAGS="$CPPFLAGS_SAVED"
+       	LDFLAGS="$LDFLAGS_SAVED"
+fi
+
+])