configure: add support for libdir option

index 7f4f3bd9..ea9051ab 100755
@@ -485,7 +485,7 @@ usage()
 {
 	cat <<EOF
 Usage: $0 [OPTIONS]
-	--include_dir		Path to iproute2 include dir
+	--include_dir <dir>	Path to iproute2 include dir
 	--libbpf_dir		Path to libbpf DESTDIR
 	--libbpf_force		Enable/disable libbpf by force. Available options:
 				  on: require link against libbpf, quit config if no libbpf support

@@ -502,8 +502,9 @@ else
 	while true; do
 		case "$1" in
 			--include_dir)
-				INCLUDE=$2
-				shift 2 ;;
+				shift
+				INCLUDE="$1"
+				[ "$#" -gt 0 ] && shift ;;
 			--libbpf_dir)
 				LIBBPF_DIR="$2"
 				shift 2 ;;

@@ -523,6 +524,8 @@ else
 	done
 fi
 
+[ -d "$INCLUDE" ] || usage 1
+
 echo "# Generated config based on" $INCLUDE >$CONFIG
 quiet_config >> $CONFIG
 

index ea9051ab..0f304206 100755
@@ -486,7 +486,7 @@ usage()
 	cat <<EOF
 Usage: $0 [OPTIONS]
 	--include_dir <dir>	Path to iproute2 include dir
-	--libbpf_dir		Path to libbpf DESTDIR
+	--libbpf_dir <dir>	Path to libbpf DESTDIR
 	--libbpf_force		Enable/disable libbpf by force. Available options:
 				  on: require link against libbpf, quit config if no libbpf support
 				  off: disable libbpf probing

@@ -506,8 +506,9 @@ else
 				INCLUDE="$1"
 				[ "$#" -gt 0 ] && shift ;;
 			--libbpf_dir)
-				LIBBPF_DIR="$2"
-				shift 2 ;;
+				shift
+				LIBBPF_DIR="$1"
+				[ "$#" -gt 0 ] && shift ;;
 			--libbpf_force)
 				if [ "$2" != 'on' ] && [ "$2" != 'off' ]; then
 					usage 1

@@ -525,6 +526,9 @@ else
 fi
 
 [ -d "$INCLUDE" ] || usage 1
+if [ "${LIBBPF_DIR-unused}" != "unused" ]; then
+	[ -d "$LIBBPF_DIR" ] || usage 1
+fi
 
 echo "# Generated config based on" $INCLUDE >$CONFIG
 quiet_config >> $CONFIG

index 0f304206..9ec19a5b 100755
@@ -517,10 +517,12 @@ else
 				shift 2 ;;
 			-h | --help)
 				usage 0 ;;
+			--*)
+				shift ;;
 			"")
 				break ;;
 			*)
-				shift 1 ;;
+				usage 1 ;;
 		esac
 	done
 fi

index 9ec19a5b..26e06eb8 100755
@@ -485,12 +485,12 @@ usage()
 {
 	cat <<EOF
 Usage: $0 [OPTIONS]
-	--include_dir <dir>	Path to iproute2 include dir
-	--libbpf_dir <dir>	Path to libbpf DESTDIR
-	--libbpf_force		Enable/disable libbpf by force. Available options:
-				  on: require link against libbpf, quit config if no libbpf support
-				  off: disable libbpf probing
-	-h | --help		Show this usage info
+	--include_dir <dir>		Path to iproute2 include dir
+	--libbpf_dir <dir>		Path to libbpf DESTDIR
+	--libbpf_force <on|off>		Enable/disable libbpf by force. Available options:
+					  on: require link against libbpf, quit config if no libbpf support
+					  off: disable libbpf probing
+	-h | --help			Show this usage info
 EOF
 	exit $1
 }

@@ -499,31 +499,25 @@ EOF
 if [ $# -eq 1 ] && [ "$(echo $1 | cut -c 1)" != '-' ]; then
 	INCLUDE="$1"
 else
-	while true; do
+	while [ "$#" -gt 0 ]; do
 		case "$1" in
 			--include_dir)
 				shift
-				INCLUDE="$1"
-				[ "$#" -gt 0 ] && shift ;;
+				INCLUDE="$1" ;;
 			--libbpf_dir)
 				shift
-				LIBBPF_DIR="$1"
-				[ "$#" -gt 0 ] && shift ;;
+				LIBBPF_DIR="$1" ;;
 			--libbpf_force)
-				if [ "$2" != 'on' ] && [ "$2" != 'off' ]; then
-					usage 1
-				fi
-				LIBBPF_FORCE=$2
-				shift 2 ;;
+				shift
+				LIBBPF_FORCE="$1" ;;
 			-h | --help)
 				usage 0 ;;
 			--*)
-				shift ;;
-			"")
-				break ;;
+				;;
 			*)
 				usage 1 ;;
 		esac
+		[ "$#" -gt 0 ] && shift
 	done
 fi
 

@@ -531,6 +525,11 @@ fi
 if [ "${LIBBPF_DIR-unused}" != "unused" ]; then
 	[ -d "$LIBBPF_DIR" ] || usage 1
 fi
+if [ "${LIBBPF_FORCE-unused}" != "unused" ]; then
+	if [ "$LIBBPF_FORCE" != 'on' ] && [ "$LIBBPF_FORCE" != 'off' ]; then
+		usage 1
+	fi
+fi
 
 echo "# Generated config based on" $INCLUDE >$CONFIG
 quiet_config >> $CONFIG

index 26e06eb8..9a2645d9 100755
@@ -504,12 +504,18 @@ else
 			--include_dir)
 				shift
 				INCLUDE="$1" ;;
+			--include_dir=*)
+				INCLUDE="${1#*=}" ;;
 			--libbpf_dir)
 				shift
 				LIBBPF_DIR="$1" ;;
+			--libbpf_dir=*)
+				LIBBPF_DIR="${1#*=}" ;;
 			--libbpf_force)
 				shift
 				LIBBPF_FORCE="$1" ;;
+			--libbpf_force=*)
+				LIBBPF_FORCE="${1#*=}" ;;
 			-h | --help)
 				usage 0 ;;
 			--*)

index 9a2645d9..05e23eff 100755
@@ -3,6 +3,7 @@
 # This is not an autoconf generated configure
 
 INCLUDE="$PWD/include"
+PREFIX="/usr"
 
 # Output file which is input to Makefile
 CONFIG=config.mk

@@ -490,6 +491,7 @@ Usage: $0 [OPTIONS]
 	--libbpf_force <on|off>		Enable/disable libbpf by force. Available options:
 					  on: require link against libbpf, quit config if no libbpf support
 					  off: disable libbpf probing
+	--prefix <dir>			Path prefix of the lib files to install
 	-h | --help			Show this usage info
 EOF
 	exit $1

@@ -516,6 +518,11 @@ else
 				LIBBPF_FORCE="$1" ;;
 			--libbpf_force=*)
 				LIBBPF_FORCE="${1#*=}" ;;
+			--prefix)
+				shift
+				PREFIX="$1" ;;
+			--prefix=*)
+				PREFIX="${1#*=}" ;;
 			-h | --help)
 				usage 0 ;;
 			--*)

@@ -536,6 +543,7 @@ if [ "${LIBBPF_FORCE-unused}" != "unused" ]; then
 		usage 1
 	fi
 fi
+[ -z "$PREFIX" ] && usage 1
 
 echo "# Generated config based on" $INCLUDE >$CONFIG
 quiet_config >> $CONFIG

index 5eddd504..f6214534 100644
@@ -1,6 +1,8 @@
 # SPDX-License-Identifier: GPL-2.0
 # Top level Makefile for iproute2
 
+-include config.mk
+
 ifeq ("$(origin V)", "command line")
 VERBOSE = $(V)
 endif

@@ -13,7 +15,6 @@ MAKEFLAGS += --no-print-directory
 endif
 
 PREFIX?=/usr
-LIBDIR?=$(PREFIX)/lib
 SBINDIR?=/sbin
 CONFDIR?=/etc/iproute2
 NETNS_RUN_DIR?=/var/run/netns

@@ -69,7 +70,7 @@ SUBDIRS=lib ip tc bridge misc netem genl tipc devlink rdma dcb man vdpa
 LIBNETLINK=../lib/libutil.a ../lib/libnetlink.a
 LDLIBS += $(LIBNETLINK)
 
-all: config
+all: config.mk
 	@set -e; \
 	for i in $(SUBDIRS); \
 	do echo; echo $$i; $(MAKE) -C $$i; done

@@ -89,7 +90,7 @@ help:
 	@echo "Make Arguments:"
 	@echo " V=[0|1]             - set build verbosity level"
 
-config:
+config.mk:
 	@if [ ! -f config.mk -o configure -nt config.mk ]; then \
 		sh configure $(KERNEL_INCLUDE); \
 	fi

index 05e23eff..8ddff43c 100755
@@ -4,6 +4,7 @@
 
 INCLUDE="$PWD/include"
 PREFIX="/usr"
+LIBDIR="\${prefix}/lib"
 
 # Output file which is input to Makefile
 CONFIG=config.mk

@@ -149,6 +150,15 @@ EOF
 	rm -f $TMPDIR/ipttest.c $TMPDIR/ipttest
 }
 
+check_lib_dir()
+{
+	LIBDIR=$(echo $LIBDIR | sed "s|\${prefix}|$PREFIX|")
+
+	echo -n "lib directory: "
+	echo "$LIBDIR"
+	echo "LIBDIR:=$LIBDIR" >> $CONFIG
+}
+
 check_ipt()
 {
 	if ! grep TC_CONFIG_XT $CONFIG > /dev/null; then

@@ -487,6 +497,7 @@ usage()
 	cat <<EOF
 Usage: $0 [OPTIONS]
 	--include_dir <dir>		Path to iproute2 include dir
+	--libdir <dir>			Path to iproute2 lib dir
 	--libbpf_dir <dir>		Path to libbpf DESTDIR
 	--libbpf_force <on|off>		Enable/disable libbpf by force. Available options:
 					  on: require link against libbpf, quit config if no libbpf support

@@ -508,6 +519,11 @@ else
 				INCLUDE="$1" ;;
 			--include_dir=*)
 				INCLUDE="${1#*=}" ;;
+			--libdir)
+				shift
+				LIBDIR="$1" ;;
+			--libdir=*)
+				LIBDIR="${1#*=}" ;;
 			--libbpf_dir)
 				shift
 				LIBBPF_DIR="$1" ;;

@@ -544,6 +560,7 @@ if [ "${LIBBPF_FORCE-unused}" != "unused" ]; then
 	fi
 fi
 [ -z "$PREFIX" ] && usage 1
+[ -z "$LIBDIR" ] && usage 1
 
 echo "# Generated config based on" $INCLUDE >$CONFIG
 quiet_config >> $CONFIG

@@ -568,6 +585,7 @@ if ! grep -q TC_CONFIG_NO_XT $CONFIG; then
 fi
 
 echo
+check_lib_dir
 if ! grep -q TC_CONFIG_NO_XT $CONFIG; then
 	echo -n "iptables modules directory: "
 	check_ipt_lib_dir