【转】Android编译系统详解(三)——编译流程详解

.PHONY: droid
DEFAULT_GOAL := droid
$(DEFAULT_GOAL):

ifneq ($(TARGET_BUILD_APPS),)
……
droid: apps_only #如果编译app，那么droid依赖apps_only目标
else
……
droid: droidcore dist_files #默认依赖droidcore目标和dist_files目标
endif

$(call dist-for-goals, dist_files, $(EMMA_META_ZIP))
system/core/mkbootimg/Android.mk$(call dist-for-goals, dist_files, $( LOCAL_BUILT_MODULE ))
system/core/cpio/Android.mk:13:$(call dist-for-goals,dist_files,$(LOCAL_BUILT_MODULE))
system/core/adb/Android.mk:88:$(call dist-for-goals,dist_files sdk,$(LOCAL_BUILT_MODULE))
system/core/fastboot/Android.mk:68:$(call dist-for-goals,dist_files sdk,$(LOCAL_BUILT_MODULE))
external/guava/Android.mk:26:$(call dist-for-goals, dist_files, $(LOCAL_BUILT_MODULE):guava.jar)
external/yaffs2/Android.mk:28:$(call dist-for-goals, dist_files, $(LOCAL_BUILT_MODULE))
external/mp4parser/Android.mk:26:$(call dist-for-goals, dist_files, $(LOCAL_BUILT_MODULE):mp4parser.jar)
external/jsr305/Android.mk:25:$(call dist-for-goals, dist_files, $(LOCAL_BUILT_MODULE):jsr305.jar)
frameworks/support/renderscript/v8/Android.mk:29:#$(call dist-for-goals, dist_files, $(LOCAL_BUILT_MODULE):volley.jar)
frameworks/support/volley/Android.mk:29:#$(call dist-for-goals, dist_files, $(LOCAL_BUILT_MODULE):volley.jar)

droidcore: files 	systemimage \ #system.img
	$(INSTALLED_BOOTIMAGE_TARGET) \ #boot.img
	$(INSTALLED_RECOVERYIMAGE_TARGET) \#recovery.img
	$(INSTALLED_USERDATAIMAGE_TARGET) \#data.img
	$(INSTALLED_CACHEIMAGE_TARGET) \#cache.img
	$(INSTALLED_FILES_FILE)# installed-files.txt
ifneq ($(TARGET_BUILD_APPS),)
….
else
$(call dist-for-goals, droidcore,     $(INTERNAL_UPDATE_PACKAGE_TARGET) #cm_find5-img-eng.cloud.zip
    $(INTERNAL_OTA_PACKAGE_TARGET) \ # cm_find5-ota-eng.cloud.zip
    $(SYMBOLS_ZIP) \ # cm_find5-symbols-eng.cloud.zip
    $(INSTALLED_FILES_FILE) \# installed-files.txt
    $(INSTALLED_BUILD_PROP_TARGET) \# system/build.prop
    $(BUILT_TARGET_FILES_PACKAGE) \# cm_find5-target_files-eng.cloud.zip
    $(INSTALLED_ANDROID_INFO_TXT_TARGET) \# android-info.txt
    $(INSTALLED_RAMDISK_TARGET) \# ramdisk.img
    $(INSTALLED_FACTORY_RAMDISK_TARGET) \# factory_ramdisk.gz
    $(INSTALLED_FACTORY_BUNDLE_TARGET) \# cm_find5-factory_bundle- eng.cloud.zip
   )
endif

files: prebuilt         $(modules_to_install)         $(INSTALLED_ANDROID_INFO_TXT_TARGET)

……
tags_to_install :=
ifneq (,$(user_variant))
…..
  ifeq ($(user_variant),userdebug)
  tags_to_install += debug
  else
  …
  endif
endif
ifeq ($(TARGET_BUILD_VARIANT),eng)
tags_to_install := debug eng
…
endif
ifeq ($(TARGET_BUILD_VARIANT),tests)
tags_to_install := debug eng tests
endif
ifdef is_sdk_build
tags_to_install := debug eng
else # !sdk
endif
……
# ------------------------------------------------------------
# Define a function that, given a list of module tags, returns
# non-empty if that module should be installed in /system.
 
# For most goals, anything not tagged with the "tests" tag should
# be installed in /system.
define should-install-to-system
$(if $(filter tests,$(1)),,true)
endef
ifdef is_sdk_build
# For the sdk goal, anything with the "samples" tag should be
# installed in /data even if that module also has "eng"/"debug"/"user".
define should-install-to-system
$(if $(filter samples tests,$(1)),,true)
endef
endif
…
#接下来根据配置计算要查找的subdirs目录
ifneq ($(dont_bother),true)
…
ifeq ($(SDK_ONLY),true)
include $(TOPDIR)sdk/build/sdk_only_whitelist.mk
include $(TOPDIR)development/build/sdk_only_whitelist.mk
# Exclude tools/acp when cross-compiling windows under linux
ifeq ($(findstring Linux,$(UNAME)),)
subdirs += build/tools/acp
endif
 
else	# !SDK_ONLY
ifeq ($(BUILD_TINY_ANDROID), true)
subdirs := 	bionic 	system/core 	system/extras/ext4_utils 	system/extras/su 	build/libs 	build/target 	build/tools/acp 	external/gcc-demangle 	external/mksh 	external/openssl 	external/yaffs2 	external/zlib
else	# !BUILD_TINY_ANDROID
subdirs := $(TOP) 
FULL_BUILD := true
endif	# !BUILD_TINY_ANDROID
endif
# Before we go and include all of the module makefiles, stash away
# the PRODUCT_* values so that later we can verify they are not modified.
stash_product_vars:=true
ifeq ($(stash_product_vars),true)
  $(call stash-product-vars, __STASHED)
endif
….
ifneq ($(ONE_SHOT_MAKEFILE),)
include $(ONE_SHOT_MAKEFILE)
CUSTOM_MODULES := $(sort $(call get-tagged-modules,$(ALL_MODULE_TAGS)))
FULL_BUILD :=
…
else # ONE_SHOT_MAKEFILE
#
# Include all of the makefiles in the system
#
 
# Can‘t use first-makefiles-under here because
# --mindepth=2 makes the prunes not work.
subdir_makefiles := 	$(shell build/tools/findleaves.py --prune=out --prune=.repo --prune=.git $(subdirs) Android.mk)
 
include $(subdir_makefiles)
 
endif # ONE_SHOT_MAKEFILE
……
ifeq ($(stash_product_vars),true)
  $(call assert-product-vars, __STASHED)
endif
…
# -------------------------------------------------------------------
# Fix up CUSTOM_MODULES to refer to installed files rather than
# just bare module names.  Leave unknown modules alone in case
# they‘re actually full paths to a particular file.
known_custom_modules := $(filter $(ALL_MODULES),$(CUSTOM_MODULES))
unknown_custom_modules := $(filter-out $(ALL_MODULES),$(CUSTOM_MODULES))
CUSTOM_MODULES := 	$(call module-installed-files,$(known_custom_modules)) 	$(unknown_custom_modules
# -------------------------------------------------------------------
# Figure out our module sets.
#
# Of the modules defined by the component makefiles,
# determine what we actually want to build.
 
ifdef FULL_BUILD
  # The base list of modules to build for this product is specified
  # by the appropriate product definition file, which was included
  # by product_config.make.
  product_MODULES := $(PRODUCTS.$(INTERNAL_PRODUCT).PRODUCT_PACKAGES)
  # Filter out the overridden packages before doing expansion
  product_MODULES := $(filter-out $(foreach p, $(product_MODULES),       $(PACKAGES.$(p).OVERRIDES)), $(product_MODULES))
  $(call expand-required-modules,product_MODULES,$(product_MODULES))
  product_FILES := $(call module-installed-files, $(product_MODULES))
  ifeq (0,1)
    $(info product_FILES for $(TARGET_DEVICE) ($(INTERNAL_PRODUCT)):)
    $(foreach p,$(product_FILES),$(info :   $(p)))
    $(error done)
  endif
else
  # We‘re not doing a full build, and are probably only including
  # a subset of the module makefiles.  Don‘t try to build any modules
  # requested by the product, because we probably won‘t have rules
  # to build them.
  product_FILES :=
endif
# When modules are tagged with debug eng or tests, they are installed
# for those variants regardless of what the product spec says.
debug_MODULES := $(sort         $(call get-tagged-modules,debug)         $(call module-installed-files, $(PRODUCTS.$(INTERNAL_PRODUCT).PRODUCT_PACKAGES_DEBUG))     )
eng_MODULES := $(sort         $(call get-tagged-modules,eng)         $(call module-installed-files, $(PRODUCTS.$(INTERNAL_PRODUCT).PRODUCT_PACKAGES_ENG))     )
tests_MODULES := $(sort         $(call get-tagged-modules,tests)         $(call module-installed-files, $(PRODUCTS.$(INTERNAL_PRODUCT).PRODUCT_PACKAGES_TESTS)) )
# TODO: Remove the 3 places in the tree that use ALL_DEFAULT_INSTALLED_MODULES
# and get rid of it from this list.
# TODO: The shell is chosen by magic.  Do we still need this?
modules_to_install := $(sort     $(ALL_DEFAULT_INSTALLED_MODULES)     $(product_FILES)     $(foreach tag,$(tags_to_install),$($(tag)_MODULES))     $(call get-tagged-modules, shell_$(TARGET_SHELL))     $(CUSTOM_MODULES)   )
# Some packages may override others using LOCAL_OVERRIDES_PACKAGES.
# Filter out (do not install) any overridden packages.
overridden_packages := $(call get-package-overrides,$(modules_to_install))
ifdef overridden_packages
#  old_modules_to_install := $(modules_to_install)
  modules_to_install :=       $(filter-out $(foreach p,$(overridden_packages),$(p) %/$(p).apk),           $(modules_to_install))
endif
#$(error filtered out
#           $(filter-out $(modules_to_install),$(old_modules_to_install)))
 
# Don‘t include any GNU targets in the SDK.  It‘s ok (and necessary)
# to build the host tools, but nothing that‘s going to be installed
# on the target (including static libraries).
ifdef is_sdk_build
  target_gnu_MODULES :=               $(filter                       $(TARGET_OUT_INTERMEDIATES)/%                       $(TARGET_OUT)/%                       $(TARGET_OUT_DATA)/%,                               $(sort $(call get-tagged-modules,gnu)))
  $(info Removing from sdk:)$(foreach d,$(target_gnu_MODULES),$(info : $(d)))
  modules_to_install :=               $(filter-out $(target_gnu_MODULES),$(modules_to_install))
 
  # Ensure every module listed in PRODUCT_PACKAGES* gets something installed
  # TODO: Should we do this for all builds and not just the sdk?
  $(foreach m, $(PRODUCTS.$(INTERNAL_PRODUCT).PRODUCT_PACKAGES),     $(if $(strip $(ALL_MODULES.$(m).INSTALLED)),,      $(warning $(ALL_MODULES.$(m).MAKEFILE): Module ‘$(m)‘ in PRODUCT_PACKAGES has nothing to install!)))
  $(foreach m, $(PRODUCTS.$(INTERNAL_PRODUCT).PRODUCT_PACKAGES_DEBUG),     $(if $(strip $(ALL_MODULES.$(m).INSTALLED)),,      $(warning $(ALL_MODULES.$(m).MAKEFILE): Module ‘$(m)‘ in PRODUCT_PACKAGES_DEBUG has nothing to install!)))
  $(foreach m, $(PRODUCTS.$(INTERNAL_PRODUCT).PRODUCT_PACKAGES_ENG),     $(if $(strip $(ALL_MODULES.$(m).INSTALLED)),,      $(warning $(ALL_MODULES.$(m).MAKEFILE): Module ‘$(m)‘ in PRODUCT_PACKAGES_ENG has nothing to install!)))
  $(foreach m, $(PRODUCTS.$(INTERNAL_PRODUCT).PRODUCT_PACKAGES_TESTS),     $(if $(strip $(ALL_MODULES.$(m).INSTALLED)),,      $(warning $(ALL_MODULES.$(m).MAKEFILE): Module ‘$(m)‘ in PRODUCT_PACKAGES_TESTS has nothing to install!)))
endif
 
# Install all of the host modules
modules_to_install += $(sort $(modules_to_install) $(ALL_HOST_INSTALLED_FILES))
 
# build/core/Makefile contains extra stuff that we don‘t want to pollute this
# top-level makefile with.  It expects that ALL_DEFAULT_INSTALLED_MODULES
# contains everything that‘s built during the current make, but it also further
# extends ALL_DEFAULT_INSTALLED_MODULES.
ALL_DEFAULT_INSTALLED_MODULES := $(modules_to_install)
include $(BUILD_SYSTEM)/Makefile
modules_to_install := $(sort $(ALL_DEFAULT_INSTALLED_MODULES))
ALL_DEFAULT_INSTALLED_MODULES :=
 
endif # dont_bother
# These are additional goals that we build, in order to make sure that there
# is as little code as possible in the tree that doesn‘t build.
modules_to_check := $(foreach m,$(ALL_MODULES),$(ALL_MODULES.$(m).CHECKED))
 
# If you would like to build all goals, and not skip any intermediate
# steps, you can pass the "all" modifier goal on the commandline.
ifneq ($(filter all,$(MAKECMDGOALS)),)
modules_to_check += $(foreach m,$(ALL_MODULES),$(ALL_MODULES.$(m).BUILT))
endif
 
# for easier debugging
modules_to_check := $(sort $(modules_to_check))
#$(error modules_to_check $(modules_to_check))