integrate mklibs.py support into the build process

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@17173 3c298f89-4303-0410-b956-a3cf2f4a3e73

Config.in

@@ -126,6 +126,14 @@ choice
 
 endchoice
 
+config USE_MKLIBS
+	bool "Strip unnecessary functions from libraries"
+	help
+	  Reduces libraries to only those functions that are necessary for using all
+	  selected packages (including those selected as <M>)
+	  Note that this will make the system libraries incompatible with most of the packages
+	  that are not selected during the build process
+
 comment "Package build options"
 
 config DEBUG

package/Makefile

@@ -25,6 +25,40 @@ $(curdir)/install:=$(curdir)/install-cleanup
 $(curdir)/cleanup: $(TMP_DIR)/.build
 	rm -rf $(TARGET_DIR) $(STAGING_DIR_ROOT)
 
+ifdef CONFIG_USE_MKLIBS
+  define mklibs
+	rm -rf $(TMP_DIR)/mklibs-progs $(TMP_DIR)/mklibs-out
+	# first find all programs and add them to the mklibs list
+	find $(STAGING_DIR_ROOT) -type f -perm +100 -exec \
+		file -r -N -F '' {} + | \
+		awk ' /executable.*dynamically/ { print $$1 }' > $(TMP_DIR)/mklibs-progs
+	# find all loadable objects that are not regular libraries and add them to the list as well
+	find $(STAGING_DIR_ROOT) -type f -name \*.so\* -exec \
+		file -r -N -F '' {} + | \
+		awk ' /shared object/ { print $$1 }' >> $(TMP_DIR)/mklibs-progs
+	mkdir -p $(TMP_DIR)/mklibs-out
+	$(STAGING_DIR_HOST)/bin/mklibs.py -D -v \
+		-d $(TMP_DIR)/mklibs-out \
+		--sysroot $(STAGING_DIR_ROOT) \
+		-L /lib \
+		-L /usr/lib \
+		--ldlib $(patsubst $(STAGING_DIR_ROOT)/%,/%,$(firstword $(wildcard \
+			$(foreach name,ld-uClibc.so.* ld-linux.so.*, \
+			  $(STAGING_DIR_ROOT)/lib/$(name) \
+			)))) \
+		--target $(REAL_GNU_TARGET_NAME) \
+		`cat $(TMP_DIR)/mklibs-progs` 2>&1
+	$(RSTRIP) $(TMP_DIR)/mklibs-out
+	for lib in `ls $(TMP_DIR)/mklibs-out/*.so.* 2>/dev/null`; do \
+		LIB="$${lib##*/}"; \
+		DEST="`ls "$(TARGET_DIR)/lib/$$LIB" "$(TARGET_DIR)/usr/lib/$$LIB" 2>/dev/null`"; \
+		[ -n "$$DEST" ] || continue; \
+		echo "Copying stripped library $$lib to $$DEST"; \
+		cp "$$lib" "$$DEST" || exit 1; \
+	done
+  endef
+endif
+
 $(curdir)/rootfs-prepare: $(TMP_DIR)/.build
 	@-$(MAKE) package/preconfig
 	@if [ -d $(TOPDIR)/files ]; then \
@@ -42,6 +76,7 @@ $(curdir)/rootfs-prepare: $(TMP_DIR)/.build
 	@-find $(TARGET_DIR) -name .svn  | $(XARGS) rm -rf
 	@-find $(TARGET_DIR) -name '.#*' | $(XARGS) rm -f
 	$(if $(CONFIG_CLEAN_IPKG),rm -rf $(TARGET_DIR)/usr/lib/ipkg)
+	$(call mklibs)
 
 $(curdir)/index: FORCE
 	@(cd $(PACKAGE_DIR); $(SCRIPT_DIR)/ipkg-make-index.sh . > Packages && \