Harden dependency on generated sources.

Previously if a library has custom generated headers in
LOCAL_GENERATED_SOURCES and export its include path with
LOCAL_EXPORT_C_INCLUDE_DIRS, there is almost no way for the users of the
library to set up dependency of their object files on the generated
headers.
This change makes the generated sources dependency of the library's
export_includes, which is guaranteed generated before client code gets
compiled.

Also we added proto-generated cpp files to my_generated_sources so that
we can deal solely with $(my_generated_sources). Because many
Android.mks assume the generted .pb.hs are in $(generated_sources_dir)
instead of $(intermediates), we have to generate the source files in
$(generated_sources_dir) and make a copy in $(intermediates).

Bug: 28622149
Change-Id: I73b21443fa706f3735faf16356ed8c08fbfecca6

core/binary.mk

@@ -654,59 +654,57 @@ endif
 ## Compile the .proto files to .cc (or .c) and then to .o
 ###########################################################
 proto_sources := $(filter %.proto,$(my_src_files))
-proto_generated_objects :=
-proto_generated_headers :=
 ifneq ($(proto_sources),)
-proto_generated_sources_dir := $(generated_sources_dir)/proto
+proto_gen_dir := $(generated_sources_dir)/proto
-proto_generated_obj_dir := $(intermediates)/proto
 proto_sources_fullpath := $(addprefix $(LOCAL_PATH)/, $(proto_sources))
 
+my_rename_cpp_ext :=
 ifneq (,$(filter nanopb-c nanopb-c-enable_malloc, $(LOCAL_PROTOC_OPTIMIZE_TYPE)))
 my_proto_source_suffix := .c
 my_proto_c_includes := external/nanopb-c
-my_protoc_flags := --nanopb_out=$(proto_generated_sources_dir) \
+my_protoc_flags := --nanopb_out=$(proto_gen_dir) \
     --plugin=external/nanopb-c/generator/protoc-gen-nanopb
 my_protoc_deps := $(NANOPB_SRCS) $(proto_sources_fullpath:%.proto=%.options)
 else
-my_proto_source_suffix := .cc
+my_proto_source_suffix := $(LOCAL_CPP_EXTENSION)
+ifneq ($(my_proto_source_suffix),.cc)
+# aprotoc is hardcoded to write out only .cc file.
+# We need to rename the extension to $(LOCAL_CPP_EXTENSION) if it's not .cc.
+my_rename_cpp_ext := true
+endif
 my_proto_c_includes := external/protobuf/src
 my_cflags += -DGOOGLE_PROTOBUF_NO_RTTI
-my_protoc_flags := --cpp_out=$(proto_generated_sources_dir)
+my_protoc_flags := --cpp_out=$(proto_gen_dir)
 my_protoc_deps :=
 endif
-my_proto_c_includes += $(proto_generated_sources_dir)
+my_proto_c_includes += $(proto_gen_dir)
 
-proto_generated_sources := $(addprefix $(proto_generated_sources_dir)/, \
+proto_generated_cpps := $(addprefix $(proto_gen_dir)/, \
     $(patsubst %.proto,%.pb$(my_proto_source_suffix),$(proto_sources_fullpath)))
-proto_generated_headers := $(patsubst %.pb$(my_proto_source_suffix),%.pb.h, $(proto_generated_sources))
-proto_generated_objects := $(addprefix $(proto_generated_obj_dir)/, \
-    $(patsubst %.proto,%.pb.o,$(proto_sources_fullpath)))
-$(call track-src-file-obj,$(proto_sources),$(proto_generated_objects))
 
 # Ensure the transform-proto-to-cc rule is only defined once in multilib build.
-ifndef $(my_prefix)_$(LOCAL_MODULE_CLASS)_$(LOCAL_MODULE)_proto_defined
+ifndef $(my_host)$(LOCAL_MODULE_CLASS)_$(LOCAL_MODULE)_proto_defined
-$(proto_generated_sources): PRIVATE_PROTO_INCLUDES := $(TOP)
+$(proto_generated_cpps): PRIVATE_PROTO_INCLUDES := $(TOP)
-$(proto_generated_sources): PRIVATE_PROTOC_FLAGS := $(LOCAL_PROTOC_FLAGS) $(my_protoc_flags)
+$(proto_generated_cpps): PRIVATE_PROTOC_FLAGS := $(LOCAL_PROTOC_FLAGS) $(my_protoc_flags)
-$(proto_generated_sources): $(proto_generated_sources_dir)/%.pb$(my_proto_source_suffix): %.proto $(my_protoc_deps) $(PROTOC)
+$(proto_generated_cpps): PRIVATE_RENAME_CPP_EXT := $(my_rename_cpp_ext)
+$(proto_generated_cpps): $(proto_gen_dir)/%.pb$(my_proto_source_suffix): %.proto $(my_protoc_deps) $(PROTOC)
 	$(transform-proto-to-cc)
 
-# This is just a dummy rule to make sure gmake doesn't skip updating the dependents.
+$(my_host)$(LOCAL_MODULE_CLASS)_$(LOCAL_MODULE)_proto_defined := true
-$(proto_generated_headers): $(proto_generated_sources_dir)/%.pb.h: $(proto_generated_sources_dir)/%.pb$(my_proto_source_suffix)
-	@echo "Updated header file $@."
-	$(hide) touch $@
-
-$(my_prefix)_$(LOCAL_MODULE_CLASS)_$(LOCAL_MODULE)_proto_defined := true
-endif  # transform-proto-to-cc rule included only once
-
-$(proto_generated_objects): PRIVATE_ARM_MODE := $(normal_objects_mode)
-$(proto_generated_objects): PRIVATE_ARM_CFLAGS := $(normal_objects_cflags)
-$(proto_generated_objects): $(proto_generated_obj_dir)/%.o: $(proto_generated_sources_dir)/%$(my_proto_source_suffix) $(proto_generated_headers)
-ifeq ($(my_proto_source_suffix),.c)
-	$(transform-$(PRIVATE_HOST)c-to-o)
-else
-	$(transform-$(PRIVATE_HOST)cpp-to-o)
 endif
-$(call include-depfiles-for-objs, $(proto_generated_objects))
+# Ideally we can generate the source directly into $(intermediates).
+# But many Android.mks assume the .pb.hs are in $(generated_sources_dir).
+# As a workaround, we make a copy in the $(intermediates).
+proto_intermediate_dir := $(intermediates)/proto
+proto_intermediate_cpps := $(patsubst $(proto_gen_dir)/%,$(proto_intermediate_dir)/%,\
+    $(proto_generated_cpps))
+$(proto_intermediate_cpps) : $(proto_intermediate_dir)/% : $(proto_gen_dir)/%
+	@echo "Copy: $@"
+	$(copy-file-to-target)
+	$(hide) cp $(basename $<).h $(basename $@).h
+$(call track-src-file-gen,$(proto_sources),$(proto_intermediate_cpps))
+
+my_generated_sources += $(proto_intermediate_cpps)
 
 my_c_includes += $(my_proto_c_includes)
 # Auto-export the generated proto source dir.
@@ -892,7 +890,7 @@ $(call track-src-file-obj,$(patsubst %,%.arm,$(cpp_arm_sources)),$(cpp_arm_objec
 dotdot_arm_objects :=
 $(foreach s,$(dotdot_arm_sources),\
   $(eval $(call compile-dotdot-cpp-file,$(s),\
-  $(yacc_cpps) $(proto_generated_headers) $(my_additional_dependencies),\
+  $(my_additional_dependencies),\
   dotdot_arm_objects)))
 $(call track-src-file-obj,$(patsubst %,%.arm,$(dotdot_arm_sources)),$(dotdot_arm_objects))
 
@@ -900,7 +898,7 @@ dotdot_sources := $(filter ../%$(LOCAL_CPP_EXTENSION),$(my_src_files))
 dotdot_objects :=
 $(foreach s,$(dotdot_sources),\
   $(eval $(call compile-dotdot-cpp-file,$(s),\
-    $(yacc_cpps) $(proto_generated_headers) $(my_additional_dependencies),\
+    $(my_additional_dependencies),\
     dotdot_objects)))
 $(call track-src-file-obj,$(dotdot_sources),$(dotdot_objects))
 
@@ -918,7 +916,6 @@ cpp_objects        := $(cpp_arm_objects) $(cpp_normal_objects)
 ifneq ($(strip $(cpp_objects)),)
 $(cpp_objects): $(intermediates)/%.o: \
     $(TOPDIR)$(LOCAL_PATH)/%$(LOCAL_CPP_EXTENSION) \
-    $(yacc_cpps) $(proto_generated_headers) \
     $(my_additional_dependencies)
 	$(transform-$(PRIVATE_HOST)cpp-to-o)
 $(call include-depfiles-for-objs, $(cpp_objects))
@@ -940,8 +937,7 @@ ifneq ($(strip $(gen_cpp_objects)),)
 $(gen_cpp_objects): PRIVATE_ARM_MODE := $(normal_objects_mode)
 $(gen_cpp_objects): PRIVATE_ARM_CFLAGS := $(normal_objects_cflags)
 $(gen_cpp_objects): $(intermediates)/%.o: \
-    $(intermediates)/%$(LOCAL_CPP_EXTENSION) $(yacc_cpps) \
+    $(intermediates)/%$(LOCAL_CPP_EXTENSION) \
-    $(proto_generated_headers) \
     $(my_additional_dependencies)
 	$(transform-$(PRIVATE_HOST)cpp-to-o)
 $(call include-depfiles-for-objs, $(gen_cpp_objects))
@@ -996,7 +992,7 @@ $(call track-src-file-obj,$(patsubst %,%.arm,$(c_arm_sources)),$(c_arm_objects))
 dotdot_arm_objects :=
 $(foreach s,$(dotdot_arm_sources),\
   $(eval $(call compile-dotdot-c-file,$(s),\
-    $(yacc_cpps) $(proto_generated_headers) $(my_additional_dependencies),\
+    $(my_additional_dependencies),\
     dotdot_arm_objects)))
 $(call track-src-file-obj,$(patsubst %,%.arm,$(dotdot_arm_sources)),$(dotdot_arm_objects))
 
@@ -1004,7 +1000,7 @@ dotdot_sources := $(filter ../%.c, $(my_src_files))
 dotdot_objects :=
 $(foreach s, $(dotdot_sources),\
   $(eval $(call compile-dotdot-c-file,$(s),\
-    $(yacc_cpps) $(proto_generated_headers) $(my_additional_dependencies),\
+    $(my_additional_dependencies),\
     dotdot_objects)))
 $(call track-src-file-obj,$(dotdot_sources),$(dotdot_objects))
 
@@ -1020,7 +1016,7 @@ $(dotdot_objects) $(c_normal_objects): PRIVATE_ARM_CFLAGS := $(normal_objects_cf
 c_objects        := $(c_arm_objects) $(c_normal_objects)
 
 ifneq ($(strip $(c_objects)),)
-$(c_objects): $(intermediates)/%.o: $(TOPDIR)$(LOCAL_PATH)/%.c $(yacc_cpps) $(proto_generated_headers) \
+$(c_objects): $(intermediates)/%.o: $(TOPDIR)$(LOCAL_PATH)/%.c \
     $(my_additional_dependencies)
 	$(transform-$(PRIVATE_HOST)c-to-o)
 $(call include-depfiles-for-objs, $(c_objects))
@@ -1041,7 +1037,7 @@ ifneq ($(strip $(gen_c_objects)),)
 # TODO: support compiling certain generated files as arm.
 $(gen_c_objects): PRIVATE_ARM_MODE := $(normal_objects_mode)
 $(gen_c_objects): PRIVATE_ARM_CFLAGS := $(normal_objects_cflags)
-$(gen_c_objects): $(intermediates)/%.o: $(intermediates)/%.c $(yacc_cpps) $(proto_generated_headers) \
+$(gen_c_objects): $(intermediates)/%.o: $(intermediates)/%.c \
     $(my_additional_dependencies)
 	$(transform-$(PRIVATE_HOST)c-to-o)
 $(call include-depfiles-for-objs, $(gen_c_objects))
@@ -1056,7 +1052,7 @@ objc_objects := $(addprefix $(intermediates)/,$(objc_sources:.m=.o))
 $(call track-src-file-obj,$(objc_sources),$(objc_objects))
 
 ifneq ($(strip $(objc_objects)),)
-$(objc_objects): $(intermediates)/%.o: $(TOPDIR)$(LOCAL_PATH)/%.m $(yacc_cpps) $(proto_generated_headers) \
+$(objc_objects): $(intermediates)/%.o: $(TOPDIR)$(LOCAL_PATH)/%.m \
     $(my_additional_dependencies)
 	$(transform-$(PRIVATE_HOST)m-to-o)
 $(call include-depfiles-for-objs, $(objc_objects))
@@ -1071,7 +1067,7 @@ objcpp_objects := $(addprefix $(intermediates)/,$(objcpp_sources:.mm=.o))
 $(call track-src-file-obj,$(objcpp_sources),$(objcpp_objects))
 
 ifneq ($(strip $(objcpp_objects)),)
-$(objcpp_objects): $(intermediates)/%.o: $(TOPDIR)$(LOCAL_PATH)/%.mm $(yacc_cpps) $(proto_generated_headers) \
+$(objcpp_objects): $(intermediates)/%.o: $(TOPDIR)$(LOCAL_PATH)/%.mm \
     $(my_additional_dependencies)
 	$(transform-$(PRIVATE_HOST)mm-to-o)
 $(call include-depfiles-for-objs, $(objcpp_objects))
@@ -1201,8 +1197,7 @@ normal_objects := \
     $(c_objects) \
     $(gen_c_objects) \
     $(objc_objects) \
-    $(objcpp_objects) \
+    $(objcpp_objects)
-    $(proto_generated_objects)
 
 new_order_normal_objects := $(foreach f,$(my_src_files),$(my_src_file_obj_$(f)))
 new_order_normal_objects += $(foreach f,$(my_gen_src_files),$(my_src_file_obj_$(f)))
@@ -1483,11 +1478,9 @@ export_include_deps += $(strip \
    $(foreach l,$(LOCAL_EXPORT_STATIC_LIBRARY_HEADERS), \
      $(call intermediates-dir-for,STATIC_LIBRARIES,$(l),$(LOCAL_IS_HOST_MODULE),,$(LOCAL_2ND_ARCH_VAR_PREFIX),$(my_host_cross))/export_includes))
 $(export_includes): PRIVATE_REEXPORTED_INCLUDES := $(export_include_deps)
-# Make sure .pb.h are already generated before any dependent source files get compiled.
+# By adding $(my_generated_sources) it makes sure the headers get generated
-# Similarly, the generated DBus headers need to exist before we export their location.
+# before any dependent source files get compiled.
-# People are not going to consume the aidl generated cpp file, but the cpp file is
+$(export_includes) : $(my_generated_sources) $(export_include_deps)
-# generated after the headers, so this is a convenient way to ensure the headers exist.
-$(export_includes) : $(proto_generated_headers) $(dbus_generated_headers) $(aidl_gen_cpp) $(export_include_deps)
 	@echo Export includes file: $< -- $@
 	$(hide) mkdir -p $(dir $@) && rm -f $@.tmp && touch $@.tmp
 ifdef my_export_c_include_dirs

core/definitions.mk

@@ -1109,6 +1109,9 @@ $(hide) $(PROTOC) \
 	$(addprefix --proto_path=, $(PRIVATE_PROTO_INCLUDES)) \
 	$(PRIVATE_PROTOC_FLAGS) \
 	$<
+@# aprotoc outputs only .cc. Rename it to .cpp if necessary.
+$(if $(PRIVATE_RENAME_CPP_EXT),\
+  $(hide) mv $(basename $@).cc $@)
 endef