3360. [bug] isc-config.sh did not honour includedir and libdir

when set via configure. [RT #33345]

CHANGES

@@ -1,3 +1,6 @@
+3360.	[bug]		isc-config.sh did not honour includedir and libdir
+			when set via configure. [RT #33345]
+
 3559.	[func]		Check that both forms of Sender Policy Framework
 			records exist or do not exist. [RT #33355]
 

isc-config.sh.in

@@ -20,6 +20,8 @@
 prefix=@prefix@
 exec_prefix=@exec_prefix@
 exec_prefix_set=
+includedir=@includedir@
+libdir=@libdir@
 
 usage()
 {
@@ -57,6 +59,7 @@ while test $# -gt 0; do
 		prefix=$optarg
 		if test "x$exec_prefix_set" = x ; then
 			exec_prefix=$prefix
+			exec_prefix_set=true
 		fi
 		;;
 	--prefix)
@@ -64,6 +67,7 @@ while test $# -gt 0; do
 		;;
 	--exec-prefix=*)
 		exec_prefix=$optarg
+		exec_prefix_set=true
 		;;
 	--exec-prefix)
 		echo_exec_prefix=true
@@ -115,14 +119,22 @@ if test x"$echo_exec_prefix" = x"true" ; then
 	echo $exec_prefix
 fi
 if test x"$echo_cflags" = x"true"; then
-	includes="-I${exec_prefix}/include"
+	if test x"${exec_prefix_set}" = x"true"; then
+		includes="-I${exec_prefix}/include"
+	else
+		includes="-I${includedir}"
+	fi
 	if test x"$libisc" = x"true"; then
 		includes="$includes @ALWAYS_DEFINES@ @STD_CINCLUDES@ @STD_CDEFINES@ @CCOPT@"
 	fi
 	echo $includes
 fi
 if test x"$echo_libs" = x"true"; then
-	libs=-L${exec_prefix}/lib
+	if test x"${exec_prefix_set}" = x"true"; then
+		includes="-L${exec_prefix}/lib"
+	else
+		libs="-L${libdir}"
+	fi
 	if test x"$liblwres" = x"true" ; then
 		libs="$libs -llwres"
 	fi