break up event-log-tags; generate java source files with constants

Construct the /system/etc/event-log-tags file by unioning together any
*.logtags files included in LOCAL_SRC_FILES throughout the system (with
appropriate error checking for dup tag numbers, etc.)

For java packages, generate a java source file from the logtags file for
that package that contains static integer constants for each tag name.
diff --git a/core/Makefile b/core/Makefile
index 2f316ca..05a9b86 100644
--- a/core/Makefile
+++ b/core/Makefile
@@ -472,6 +472,27 @@
 
 
 # -----------------------------------------------------------------
+
+.PHONY: event-log-tags
+
+event_log_tags_file := $(TARGET_OUT)/etc/event-log-tags
+ALL_PREBUILT += $(event_log_tag_file)
+
+# Include tags from all packages included in this product.
+event_log_tags_src := \
+    $(sort $(foreach m,\
+      $(PRODUCTS.$(INTERNAL_PRODUCT).PRODUCT_PACKAGES) \
+      $(call module-names-for-tag-list,user), \
+      $(ALL_MODULES.$(m).EVENT_LOG_TAGS)))
+
+$(event_log_tags_file): PRIVATE_SRC_FILES := $(event_log_tags_src)
+$(event_log_tags_file): $(event_log_tags_src)
+	$(hide) mkdir -p $(dir $@)
+	$(hide) build/tools/merge-event-log-tags.py -o $@ $(PRIVATE_SRC_FILES)
+
+event-log-tags: $(event_log_tags_file)
+
+# -----------------------------------------------------------------
 # Build a keystore with the authorized keys in it, used to verify the
 # authenticity of downloaded OTA packages.
 #
diff --git a/core/base_rules.mk b/core/base_rules.mk
index 64b74e7..8937360 100644
--- a/core/base_rules.mk
+++ b/core/base_rules.mk
@@ -186,11 +186,38 @@
 endif
 
 ###########################################################
+## logtags: Add .logtags files to global list, emit java source
+###########################################################
+
+logtags_sources := $(filter %.logtags,$(LOCAL_SRC_FILES))
+
+ifneq ($(strip $(logtags_sources)),)
+
+event_log_tags := $(addprefix $(LOCAL_PATH)/,$(logtags_sources))
+
+# Emit a java source file with constants for the tags, if
+# LOCAL_MODULE_CLASS is "APPS" or "JAVA_LIBRARIES".
+ifneq ($(strip $(filter $(LOCAL_MODULE_CLASS),APPS JAVA_LIBRARIES)),)
+
+logtags_java_sources := $(patsubst %.logtags,%.java,$(addprefix $(intermediates.COMMON)/src/, $(logtags_sources)))
+logtags_sources := $(addprefix $(TOP_DIR)$(LOCAL_PATH)/, $(logtags_sources))
+
+$(logtags_java_sources): $(intermediates.COMMON)/src/%.java: $(TOPDIR)$(LOCAL_PATH)/%.logtags
+	$(transform-logtags-to-java)
+
+endif
+
+else
+logtags_java_sources :=
+event_log_tags :=
+endif
+
+###########################################################
 ## Java: Compile .java files to .class
 ###########################################################
 #TODO: pull this into java.make once host and target are combined
 
-java_sources := $(addprefix $(TOP_DIR)$(LOCAL_PATH)/, $(filter %.java,$(LOCAL_SRC_FILES))) $(aidl_java_sources)
+java_sources := $(addprefix $(TOP_DIR)$(LOCAL_PATH)/, $(filter %.java,$(LOCAL_SRC_FILES))) $(aidl_java_sources) $(logtags_java_sources)
 all_java_sources := $(java_sources) $(addprefix $($(my_prefix)OUT_COMMON_INTERMEDIATES)/, $(filter %.java,$(LOCAL_INTERMEDIATE_SOURCES)))
 
 ## Java resources #########################################
@@ -432,6 +459,8 @@
     $(ALL_MODULES.$(LOCAL_MODULE).INSTALLED) $(LOCAL_INSTALLED_MODULE)
 ALL_MODULES.$(LOCAL_MODULE).REQUIRED := \
     $(ALL_MODULES.$(LOCAL_MODULE).REQUIRED) $(LOCAL_REQUIRED_MODULES)
+ALL_MODULES.$(LOCAL_MODULE).EVENT_LOG_TAGS := \
+    $(ALL_MODULES.$(LOCAL_MODULE).EVENT_LOG_TAGS) $(event_log_tags)
 
 ###########################################################
 ## Take care of LOCAL_MODULE_TAGS
diff --git a/core/config.mk b/core/config.mk
index e574124..586f403 100644
--- a/core/config.mk
+++ b/core/config.mk
@@ -201,6 +201,7 @@
 E2FSCK := e2fsck
 JARJAR := java -jar $(HOST_OUT_JAVA_LIBRARIES)/jarjar.jar
 PROGUARD := external/proguard/bin/proguard.sh
+JAVATAGS := build/tools/java-event-log-tags.py
 
 # dx is java behind a shell script; no .exe necessary.
 DX := $(HOST_OUT_EXECUTABLES)/dx
@@ -295,7 +296,6 @@
 
 PREBUILT_IS_PRESENT := $(if $(wildcard prebuilt/Android.mk),true)
 
-
 # ###############################################################
 # Collect a list of the SDK versions that we could compile against
 # For use with the LOCAL_SDK_VERSION variable for include $(BUILD_PACKAGE)
diff --git a/core/definitions.mk b/core/definitions.mk
index 06b6201..61bd562 100644
--- a/core/definitions.mk
+++ b/core/definitions.mk
@@ -717,6 +717,16 @@
 #$(AIDL) $(PRIVATE_AIDL_FLAGS) $< - | indent -nut -br -npcs -l1000 > $@
 
 
+###########################################################
+## Commands for running java-event-log-tags.py
+###########################################################
+
+define transform-logtags-to-java
+@mkdir -p $(dir $@)
+@echo "logtags: $@ <= $<"
+$(hide) $(JAVATAGS) -o $@ $<
+endef
+
 
 ###########################################################
 ## Commands for running gcc to compile a C++ file