[include] package-ipkg.mk: build sysupgrade keepfile hints out of conffiles not yet present in the package.

This applies to config directories or files that do not exist but may be created by the
user after package installation.


git-svn-id: svn://svn.openwrt.org/openwrt/trunk@23257 3c298f89-4303-0410-b956-a3cf2f4a3e73

include/package-ipkg.mk

@@ -49,6 +49,7 @@ ifeq ($(DUMP),)
     IPKG_$(1):=$(PACKAGE_DIR)/$(1)_$(VERSION)_$(PKGARCH).ipk
     IDIR_$(1):=$(PKG_BUILD_DIR)/ipkg-$(PKGARCH)/$(1)
     INFO_$(1):=$(IPKG_STATE_DIR)/info/$(1).list
+    KEEP_$(1):=$(strip $(call Package/$(1)/conffiles))
 
     ifeq ($(if $(VARIANT),$(BUILD_VARIANT)),$(VARIANT))
     ifdef Package/$(1)/install
@@ -112,6 +113,20 @@ ifeq ($(DUMP),)
 	(cd $$(IDIR_$(1))/CONTROL; \
 		$($(1)_COMMANDS) \
 	)
+
+    ifneq ($$(KEEP_$(1)),)
+		@( \
+			keepfiles=""; \
+			for x in $$(KEEP_$(1)); do \
+				[ -f "$$(IDIR_$(1))/$$$$x" ] || keepfiles="$$$${keepfiles:+$$$$keepfiles }$$$$x"; \
+			done; \
+			[ -z "$keepfiles" ] || { \
+				mkdir -p $$(IDIR_$(1))/lib/upgrade/keep.d; \
+				for x in $$$$keepfiles; do echo $$$$x >> $$(IDIR_$(1))/lib/upgrade/keep.d/$(1); done; \
+			}; \
+		)
+    endif
+
 	$(IPKG_BUILD) $$(IDIR_$(1)) $(PACKAGE_DIR)
 	@[ -f $$(IPKG_$(1)) ]