build: allow packages to declare ABI versions to detect necessary package rebuilds

If a package directly depends on another package that recently changed
its ABI version, it will be cleaned up and rebuilt (assuming quilt is
not used).

This helps with packages that have no stable ABI, e.g. libubox, ubus,
etc.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@39720 3c298f89-4303-0410-b956-a3cf2f4a3e73

include/package-defaults.mk

@@ -32,6 +32,7 @@ define Package/Default
   else
     VERSION:=$(PKG_RELEASE)
   endif
+  ABI_VERSION:=
   ifneq ($(PKG_FLAGS),)
     PKGFLAGS:=$(PKG_FLAGS)
   else

include/package-ipkg.mk

@@ -83,6 +83,9 @@ ifeq ($(DUMP),)
       ifneq ($(CONFIG_PACKAGE_$(1))$(SDK)$(DEVELOPER),)
         IPKGS += $(1)
         compile: $$(IPKG_$(1)) $(PKG_INFO_DIR)/$(1).provides $(STAGING_DIR_ROOT)/stamp/.$(1)_installed
+        ifneq ($(ABI_VERSION),)
+        compile: $(PKG_INFO_DIR)/$(1).version
+        endif
 
         ifeq ($(CONFIG_PACKAGE_$(1)),y)
           .PHONY: $(PKG_INSTALL_STAMP).$(1)
@@ -124,6 +127,10 @@ ifeq ($(DUMP),)
 	rm -rf $(STAGING_DIR_ROOT)/tmp-$(1)
 	touch $$@
 
+    $(PKG_INFO_DIR)/$(1).version: $$(IPKG_$(1))
+	echo '$(ABI_VERSION)' | cmp -s - $$@ || \
+		echo '$(ABI_VERSION)' > $$@
+
     $(PKG_INFO_DIR)/$(1).provides: $$(IPKG_$(1))
     $$(IPKG_$(1)): $(STAMP_BUILT) $(INCLUDE_DIR)/package-ipkg.mk
 	@rm -rf $(PACKAGE_DIR)/$(1)_* $$(IDIR_$(1))

include/package.mk

@@ -39,6 +39,15 @@ include $(INCLUDE_DIR)/host.mk
 include $(INCLUDE_DIR)/unpack.mk
 include $(INCLUDE_DIR)/depends.mk
 
+find_library_dependencies = $(wildcard $(patsubst %,$(STAGING_DIR)/pkginfo/%.version, \
+	$(filter-out $(BUILD_PACKAGES),$(foreach dep, \
+		$(filter-out @%, $(patsubst +%,%,$(1))), \
+		$(if $(findstring :,$(dep)), \
+			$(word 2,$(subst :,$(space),$(dep))), \
+			$(dep) \
+		) \
+	))))
+
 STAMP_NO_AUTOREBUILD=$(wildcard $(PKG_BUILD_DIR)/.no_autorebuild)
 PREV_STAMP_PREPARED:=$(if $(STAMP_NO_AUTOREBUILD),$(wildcard $(PKG_BUILD_DIR)/.prepared*))
 ifneq ($(PREV_STAMP_PREPARED),)
@@ -227,6 +236,9 @@ define Package/$(1)/description
 endef
 endif
 
+  BUILD_PACKAGES += $(1)
+  $(STAMP_PREPARED): $$(if $(QUILT)$(DUMP),,$(call find_library_dependencies,$(DEPENDS)))
+
   $(foreach FIELD, TITLE CATEGORY SECTION VERSION,
     ifeq ($($(FIELD)),)
       $$(error Package/$(1) is missing the $(FIELD) field)