Refactor build rules for hidden API lists

The build rules were getting messy and too difficult to extend.
Extract assertions into own functions, create shared variables.

Bug: 64382372
Test: make out/target/common/obj/PACKAGING/hiddenapi-blacklist.txt
Change-Id: Ie34adb8b5349b30daa2e9e4976d285f6d9711f0e
diff --git a/Android.mk b/Android.mk
index bb37fa2..ff2a62c 100644
--- a/Android.mk
+++ b/Android.mk
@@ -867,23 +867,65 @@
 include $(BUILD_STATIC_JAVA_LIBRARY)
 
 # ==== hiddenapi lists =======================================
+include $(CLEAR_VARS)
 
-# Copy light and dark greylist over into the build folder.
-# This is for ART buildbots which need to mock these lists and have alternative
-# rules for building them. Other rules in the build system should depend on the
-# files in the build folder.
+# File names of final API lists
+LOCAL_LIGHT_GREYLIST := $(INTERNAL_PLATFORM_HIDDENAPI_LIGHT_GREYLIST)
+LOCAL_DARK_GREYLIST := $(INTERNAL_PLATFORM_HIDDENAPI_DARK_GREYLIST)
+LOCAL_BLACKLIST := $(INTERNAL_PLATFORM_HIDDENAPI_BLACKLIST)
+
+# File names of source files we will use to generate the final API lists.
+LOCAL_SRC_GREYLIST := frameworks/base/config/hiddenapi-light-greylist.txt
+LOCAL_SRC_VENDOR_LIST := frameworks/base/config/hiddenapi-vendor-list.txt
+LOCAL_SRC_PRIVATE_API := $(INTERNAL_PLATFORM_PRIVATE_DEX_API_FILE)
+LOCAL_SRC_REMOVED_API := $(INTERNAL_PLATFORM_REMOVED_DEX_API_FILE)
+
+LOCAL_SRC_ALL := \
+	$(LOCAL_SRC_GREYLIST) \
+	$(LOCAL_SRC_VENDOR_LIST) \
+	$(LOCAL_SRC_PRIVATE_API) \
+	$(LOCAL_SRC_REMOVED_API)
+
+define assert-has-no-overlap
+if [ ! -z "`comm -12 <(sort $(1)) <(sort $(2))`" ]; then \
+	echo "$(1) and $(2) should not overlap" 1>&2; \
+	comm -12 <(sort $(1)) <(sort $(2)) 1>&2; \
+	exit 1; \
+fi
+endef
+
+define assert-is-subset
+if [ ! -z "`comm -23 <(sort $(1)) <(sort $(2))`" ]; then \
+	echo "$(1) must be a subset of $(2)" 1>&2; \
+	comm -23 <(sort $(1)) <(sort $(2)) 1>&2; \
+	exit 1; \
+fi
+endef
+
+define assert-has-no-duplicates
+if [ ! -z "`sort $(1) | uniq -D`" ]; then \
+	echo "$(1) has duplicate entries" 1>&2; \
+	sort $(1) | uniq -D 1>&2; \
+	exit 1; \
+fi
+endef
+
+# The following rules build API lists in the build folder.
+# By not using files from the source tree, ART buildbots can mock these lists
+# or have alternative rules for building them. Other rules in the build system
+# should depend on the files in the build folder.
 
 # Merge light greylist from multiple files:
-#  (1) manual light greylist
-#  (2) list of usages from vendor apps
-#  (3) list of removed APIs
+#  (1) manual greylist LOCAL_SRC_GREYLIST
+#  (2) list of usages from vendor apps LOCAL_SRC_VENDOR_LIST
+#  (3) list of removed APIs in LOCAL_SRC_REMOVED_API
 #      @removed does not imply private in Doclava. We must take the subset also
-#      in PRIVATE_API.
+#      in LOCAL_SRC_PRIVATE_API.
 #  (4) list of serialization APIs
 #      Automatically adds all methods which match the signatures in
 #      REGEX_SERIALIZATION. These are greylisted in order to allow applications
 #      to write their own serializers.
-$(INTERNAL_PLATFORM_HIDDENAPI_LIGHT_GREYLIST): REGEX_SERIALIZATION := \
+$(LOCAL_LIGHT_GREYLIST): REGEX_SERIALIZATION := \
     "readObject\(Ljava/io/ObjectInputStream;\)V" \
     "readObjectNoData\(\)V" \
     "readResolve\(\)Ljava/lang/Object;" \
@@ -891,43 +933,32 @@
     "serialPersistentFields:\[Ljava/io/ObjectStreamField;" \
     "writeObject\(Ljava/io/ObjectOutputStream;\)V" \
     "writeReplace\(\)Ljava/lang/Object;"
-$(INTERNAL_PLATFORM_HIDDENAPI_LIGHT_GREYLIST): PRIVATE_API := $(INTERNAL_PLATFORM_PRIVATE_DEX_API_FILE)
-$(INTERNAL_PLATFORM_HIDDENAPI_LIGHT_GREYLIST): REMOVED_API := $(INTERNAL_PLATFORM_REMOVED_DEX_API_FILE)
-$(INTERNAL_PLATFORM_HIDDENAPI_LIGHT_GREYLIST): frameworks/base/config/hiddenapi-light-greylist.txt \
-                                               frameworks/base/config/hiddenapi-vendor-list.txt \
-                                               $(INTERNAL_PLATFORM_PRIVATE_DEX_API_FILE) \
-                                               $(INTERNAL_PLATFORM_REMOVED_DEX_API_FILE)
-	sort frameworks/base/config/hiddenapi-light-greylist.txt \
-	     frameworks/base/config/hiddenapi-vendor-list.txt \
-	     <(grep -E "\->("$(subst $(space),"|",$(REGEX_SERIALIZATION))")$$" $(PRIVATE_API)) \
-	     <(comm -12 <(sort $(REMOVED_API)) <(sort $(PRIVATE_API))) \
-	> $@
+$(LOCAL_LIGHT_GREYLIST): $(LOCAL_SRC_ALL)
+	sort $(LOCAL_SRC_GREYLIST) $(LOCAL_SRC_VENDOR_LIST) \
+	     <(grep -E "\->("$(subst $(space),"|",$(REGEX_SERIALIZATION))")$$" \
+	               $(LOCAL_SRC_PRIVATE_API)) \
+	     <(comm -12 <(sort $(LOCAL_SRC_REMOVED_API)) <(sort $(LOCAL_SRC_PRIVATE_API))) \
+	     > $@
+	$(call assert-has-no-duplicates,$@)
+	$(call assert-is-subset,$@,$(LOCAL_SRC_PRIVATE_API))
 
-$(eval $(call copy-one-file,frameworks/base/config/hiddenapi-dark-greylist.txt,\
-                            $(INTERNAL_PLATFORM_HIDDENAPI_DARK_GREYLIST)))
+# Generate an empty dark greylist.
+$(LOCAL_DARK_GREYLIST): $(LOCAL_SRC_ALL) $(LOCAL_LIGHT_GREYLIST)
+	rm -f $@
+	touch $@
+	$(call assert-is-subset,$@,$(LOCAL_SRC_PRIVATE_API))
+	$(call assert-has-no-duplicates,$@)
+	$(call assert-has-no-overlap,$@,$(LOCAL_LIGHT_GREYLIST))
 
-# Generate dark greylist as private API minus (blacklist plus light greylist).
-
-$(INTERNAL_PLATFORM_HIDDENAPI_BLACKLIST): PRIVATE_API := $(INTERNAL_PLATFORM_PRIVATE_DEX_API_FILE)
-$(INTERNAL_PLATFORM_HIDDENAPI_BLACKLIST): LIGHT_GREYLIST := $(INTERNAL_PLATFORM_HIDDENAPI_LIGHT_GREYLIST)
-$(INTERNAL_PLATFORM_HIDDENAPI_BLACKLIST): DARK_GREYLIST := $(INTERNAL_PLATFORM_HIDDENAPI_DARK_GREYLIST)
-$(INTERNAL_PLATFORM_HIDDENAPI_BLACKLIST): $(INTERNAL_PLATFORM_PRIVATE_DEX_API_FILE) \
-                                          $(INTERNAL_PLATFORM_HIDDENAPI_LIGHT_GREYLIST) \
-                                          $(INTERNAL_PLATFORM_HIDDENAPI_DARK_GREYLIST)
-	if [ ! -z "`comm -12 <(sort $(LIGHT_GREYLIST)) <(sort $(DARK_GREYLIST))`" ]; then \
-		echo "There should be no overlap between $(LIGHT_GREYLIST) and $(DARK_GREYLIST)" 1>&2; \
-		comm -12 <(sort $(LIGHT_GREYLIST)) <(sort $(DARK_GREYLIST)) 1>&2; \
-		exit 1; \
-	elif [ ! -z "`comm -13 <(sort $(PRIVATE_API)) <(sort $(LIGHT_GREYLIST))`" ]; then \
-		echo "$(LIGHT_GREYLIST) must be a subset of $(PRIVATE_API)" 1>&2; \
-		comm -13 <(sort $(PRIVATE_API)) <(sort $(LIGHT_GREYLIST)) 1>&2; \
-		exit 2; \
-	elif [ ! -z "`comm -13 <(sort $(PRIVATE_API)) <(sort $(DARK_GREYLIST))`" ]; then \
-		echo "$(DARK_GREYLIST) must be a subset of $(PRIVATE_API)" 1>&2; \
-		comm -13 <(sort $(PRIVATE_API)) <(sort $(DARK_GREYLIST)) 1>&2; \
-		exit 3; \
-	fi
-	comm -23 <(sort $(PRIVATE_API)) <(sort $(LIGHT_GREYLIST) $(DARK_GREYLIST)) > $@
+# Generate blacklist as private API minus (light greylist plus dark greylist).
+$(LOCAL_BLACKLIST): $(LOCAL_SRC_ALL) $(LOCAL_LIGHT_GREYLIST) $(LOCAL_DARK_GREYLIST)
+	comm -13 <(sort $(LOCAL_LIGHT_GREYLIST) $(LOCAL_DARK_GREYLIST)) \
+	         <(sort $(LOCAL_SRC_PRIVATE_API)) \
+	         > $@
+	$(call assert-is-subset,$@,$(LOCAL_SRC_PRIVATE_API))
+	$(call assert-has-no-duplicates,$@)
+	$(call assert-has-no-overlap,$@,$(LOCAL_LIGHT_GREYLIST))
+	$(call assert-has-no-overlap,$@,$(LOCAL_DARK_GREYLIST))
 
 # Include subdirectory makefiles
 # ============================================================