android编译分析之7—product_config.mk

顾名思义，product_config.mk为产品相关的配置makefile。（假设lunch时选择的是aosp_arm-eng）
通过该makefile，就可以将product相关makefile中定义的变量复制过来，以备其他makefile调用。这些变量包括：
TARGET_DEVICE
PRODUCT_LOCALES
PRODUCT_COPY_FILES
PRODUCT_PROPERTY_OVERRIDES
PRODUCT_PACKAGE_OVERLAYS
DEVICE_PACKAGE_OVERLAYS
等等……

首先定义了一个函数，判断字符串是否是c描述符，

###########################################################
## Return non-empty if $(1) is a C identifier; i.e., if it
## matches /^[a-zA-Z_][a-zA-Z0-9_]*$/.  We do this by first
## making sure that it isn't empty and doesn't start with
## a digit, then by removing each valid character.  If the
## final result is empty, then it was a valid C identifier.
##
## $(1): word to check
###########################################################

_ici_digits := 0 1 2 3 4 5 6 7 8 9
_ici_alphaunderscore := \
    a b c d e f g h i j k l m n o p q r s t u v w x y z \
    A B C D E F G H I J K L M N O P Q R S T U V W X Y Z _
define is-c-identifier
$(strip \
  $(if $(1), \
    $(if $(filter $(addsuffix %,$(_ici_digits)),$(1)), \
     , \
      $(eval w := $(1)) \
      $(foreach c,$(_ici_digits) $(_ici_alphaunderscore), \
        $(eval w := $(subst $(c),,$(w))) \
       ) \
      $(if $(w),,TRUE) \
      $(eval w :=) \
     ) \
   ) \
 )
endef

检测sed的版本，如果不对，make直接就error了。

# TODO: push this into the combo files; unfortunately, we don't even
# know HOST_OS at this point.
trysed := $(shell echo a | sed -E -e 's/a/b/' 2>/dev/null)
ifeq ($(trysed),b)
  SED_EXTENDED := sed -E
else
  trysed := $(shell echo c | sed -r -e 's/c/d/' 2>/dev/null)
  ifeq ($(trysed),d)
    SED_EXTENDED := sed -r
  else
    $(error Unknown sed version)
  endif
endif

下面这个函数，在目录中找到指定的文件，然后表示成PRODUCT_COPY_FILES那种格式原文件：目标目录，例如

prodir/bootanimation/boot.wav:system/media/boot.wav 

########################################################### ## List all of the files in a subdirectory in a format ## suitable for PRODUCT_COPY_FILES and ## PRODUCT_SDK_ADDON_COPY_FILES ## ## $(1): Glob to match file name ## $(2): Source directory ## $(3): Target base directory ###########################################################

define find-copy-subdir-files
$(shell find $(2) -name "$(1)" | $(SED_EXTENDED) "s:($(2)/?(.*)):\\1\\:$(3)/\\2:" | sed "s://:/:g")
endef

默认的TARGET_BUILD_VARIANT包含user userdebug eng这三种，

# These are the valid values of TARGET_BUILD_VARIANT.  Also, if anything else is passed
# as the variant in the PRODUCT-$TARGET_BUILD_PRODUCT-$TARGET_BUILD_VARIANT form,
# it will be treated as a goal, and the eng variant will be used.
INTERNAL_VALID_VARIANTS := user userdebug eng

判断make的目标是否为PRODUCT-prodname-goal这种类型，这里显然不是，

# ---------------------------------------------------------------
# Provide "PRODUCT-<prodname>-<goal>" targets, which lets you build
# a particular configuration without needing to set up the environment.
#
product_goals := $(strip $(filter PRODUCT-%,$(MAKECMDGOALS)))
ifdef product_goals
  # Scrape the product and build names out of the goal,
  # which should be of the form PRODUCT-<productname>-<buildname>.
  #
  ifneq ($(words $(product_goals)),1)
    $(error Only one PRODUCT-* goal may be specified; saw "$(product_goals)")
  endif
  goal_name := $(product_goals)
  product_goals := $(patsubst PRODUCT-%,%,$(product_goals))
  product_goals := $(subst -, ,$(product_goals))
  ifneq ($(words $(product_goals)),2)
    $(error Bad PRODUCT-* goal "$(goal_name)")
  endif

  # The product they want
  TARGET_PRODUCT := $(word 1,$(product_goals))

  # The variant they want
  TARGET_BUILD_VARIANT := $(word 2,$(product_goals))

  ifeq ($(TARGET_BUILD_VARIANT),tests)
    $(error "tests" has been deprecated as a build variant. Use it as a build goal instead.)
  endif

  # The build server wants to do make PRODUCT-dream-installclean
  # which really means TARGET_PRODUCT=dream make installclean.
  ifneq ($(filter-out $(INTERNAL_VALID_VARIANTS),$(TARGET_BUILD_VARIANT)),)
    MAKECMDGOALS := $(MAKECMDGOALS) $(TARGET_BUILD_VARIANT)
    TARGET_BUILD_VARIANT := eng
    default_goal_substitution :=
  else
    default_goal_substitution := $(DEFAULT_GOAL)
  endif

  # Replace the PRODUCT-* goal with the build goal that it refers to.
  # Note that this will ensure that it appears in the same relative
  # position, in case it matters.
  #
  # Note that modifying this will not affect the goals that make will
  # attempt to build, but it's important because we inspect this value
  # in certain situations (like for "make sdk").
  #
  MAKECMDGOALS := $(patsubst $(goal_name),$(default_goal_substitution),$(MAKECMDGOALS))

  # Define a rule for the PRODUCT-* goal, and make it depend on the
  # patched-up command-line goals as well as any other goals that we
  # want to force.
  #
.PHONY: $(goal_name)
$(goal_name): $(MAKECMDGOALS)
endif
# else: Use the value set in the environment or buildspec.mk.

判断make的目标是否为APP-appname这种类型，这里显然不是，

# ---------------------------------------------------------------
# Provide "APP-<appname>" targets, which lets you build
# an unbundled app.
#
unbundled_goals := $(strip $(filter APP-%,$(MAKECMDGOALS)))
ifdef unbundled_goals
  ifneq ($(words $(unbundled_goals)),1)
    $(error Only one APP-* goal may be specified; saw "$(unbundled_goals)"))
  endif
  TARGET_BUILD_APPS := $(strip $(subst -, ,$(patsubst APP-%,%,$(unbundled_goals))))
  ifneq ($(filter $(DEFAULT_GOAL),$(MAKECMDGOALS)),)
    MAKECMDGOALS := $(patsubst $(unbundled_goals),,$(MAKECMDGOALS))
  else
    MAKECMDGOALS := $(patsubst $(unbundled_goals),$(DEFAULT_GOAL),$(MAKECMDGOALS))
  endif

.PHONY: $(unbundled_goals)
$(unbundled_goals): $(MAKECMDGOALS)
endif # unbundled_goals

默认dalvikvm 在host主机上也要编译，

# Default to building dalvikvm on hosts that support it...
ifeq ($(HOST_OS),linux)
# ... or if the if the option is already set
ifeq ($(WITH_HOST_DALVIK),)
  WITH_HOST_DALVIK := true
endif
endif

下面要Include三个makefile，其中的函数和变量在前面已经分析过，之所以include，那肯定是要用这些函数和变量啦。

# ---------------------------------------------------------------
# Include the product definitions.
# We need to do this to translate TARGET_PRODUCT into its
# underlying TARGET_DEVICE before we start defining any rules.
#
include $(BUILD_SYSTEM)/node_fns.mk
include $(BUILD_SYSTEM)/product.mk
include $(BUILD_SYSTEM)/device.mk

TARGET_BUILD_APPS为空，走else分支，然后调用get-all-product-makefiles函数，返回所有产品的makefile列表。

ifneq ($(strip $(TARGET_BUILD_APPS)),)
# An unbundled app build needs only the core product makefiles.
all_product_configs := $(call get-product-makefiles,\ $(SRC_TARGET_DIR)/product/AndroidProducts.mk) else # Read in all of the product definitions specified by the AndroidProducts.mk # files in the tree. # 作用是将device和vendor下的AndroidProducts.mk找出来，然后全部include进来，返回包含类似aosp_flounder.mk这种的列表 all_product_configs := $(get-all-product-makefiles) endif

就像注释所写，为当前product找到对应的config makefile，

# Find the product config makefile for the current product.
# all_product_configs consists items like:
# <product_name>:<path_to_the_product_makefile>
# or just <path_to_the_product_makefile> in case the product name is the
# same as the base filename of the product config makefile.
# 这里all_product_configs都是类似makefile文件的列表，没有:
# 所以_cpm_word2为空，all_product_makefiles这时候是所有产品的mk的文件列表
# 而current_product_makefile为build/target/product/aosp_arm.mk
current_product_makefile :=
all_product_makefiles :=
$(foreach f, $(all_product_configs),\
    $(eval _cpm_words := $(subst :,$(space),$(f)))\
    $(eval _cpm_word1 := $(word 1,$(_cpm_words)))\
    $(eval _cpm_word2 := $(word 2,$(_cpm_words)))\
    $(if $(_cpm_word2),\
        $(eval all_product_makefiles += $(_cpm_word2))\
        $(if $(filter $(TARGET_PRODUCT),$(_cpm_word1)),\
            $(eval current_product_makefile += $(_cpm_word2)),),\
        $(eval all_product_makefiles += $(f))\
        $(if $(filter $(TARGET_PRODUCT),$(basename $(notdir $(f)))),\
            $(eval current_product_makefile += $(f)),)))
_cpm_words :=
_cpm_word1 :=
_cpm_word2 :=
current_product_makefile := $(strip $(current_product_makefile))
all_product_makefiles := $(strip $(all_product_makefiles))

调用import-products（build/target/product/aosp_arm.mk），将产品中定义的变量都import进来。例如，产品中定义了PRODUCT_NAME，则最终PRODUCT_NAME的值会保存在PRODUCTS.aosp_arm.mk.PRODUCT_NAME中。

# 如果目标是打印产品，如product-graph dump-products，打印产品，则是将所有的产品都import，
ifneq (,$(filter product-graph dump-products, $(MAKECMDGOALS)))
# Import all product makefiles.
$(call import-products, $(all_product_makefiles))
else
# Import just the current product.
ifndef current_product_makefile
$(error Can not locate config makefile for product "$(TARGET_PRODUCT)")
endif
ifneq (1,$(words $(current_product_makefile)))
$(error Product "$(TARGET_PRODUCT)" ambiguous: matches $(current_product_makefile))
endif
#将aosp_arm.mk 利用import-products import
$(call import-products, $(current_product_makefile))
endif  # Import all or just the current product makefile

然后调用check-all-products检查产品是否正确import，要保证必须的变量在product中都被定义。

# Sanity check
$(check-all-products)

如果make目标为dump-products，打印产品。

ifneq ($(filter dump-products, $(MAKECMDGOALS)),)
$(dump-products)
$(error done)
endif

INTERNAL_PRODUCT，为产品的全部路径，例如TARGET_PRODUCT=aosp_arm，则INTERNAL_PRODUCT为build/target/product/aosp_arm.mk

# Convert a short name like "sooner" into the path to the product
# file defining that product.
#
INTERNAL_PRODUCT := $(call resolve-short-product-name, $(TARGET_PRODUCT))
ifneq ($(current_product_makefile),$(INTERNAL_PRODUCT))
$(error PRODUCT_NAME inconsistent in $(current_product_makefile) and $(INTERNAL_PRODUCT))
endif
current_product_makefile :=
all_product_makefiles :=
all_product_configs :=

下面的变量都是在产品中定义的，将其拷贝到product_config.mk中，以备其他makefile使用。

#############################################################################

# A list of module names of BOOTCLASSPATH (jar files)
PRODUCT_BOOT_JARS := $(strip $(PRODUCTS.$(INTERNAL_PRODUCT).PRODUCT_BOOT_JARS))
PRODUCT_SYSTEM_SERVER_JARS := $(strip $(PRODUCTS.$(INTERNAL_PRODUCT).PRODUCT_SYSTEM_SERVER_JARS))

# Find the device that this product maps to.
TARGET_DEVICE := $(PRODUCTS.$(INTERNAL_PRODUCT).PRODUCT_DEVICE)

# Figure out which resoure configuration options to use for this
# product.
# 产品中定义的语言
PRODUCT_LOCALES := $(strip $(PRODUCTS.$(INTERNAL_PRODUCT).PRODUCT_LOCALES))
# TODO: also keep track of things like "port", "land" in product files.

# 如果CUSTOM_LOCALES中定义了PRODUCT_LOCALES中没有的，则添加到PRODUCT_LOCALES中
# If CUSTOM_LOCALES contains any locales not already included
# in PRODUCT_LOCALES, add them to PRODUCT_LOCALES.
extra_locales := $(filter-out $(PRODUCT_LOCALES),$(CUSTOM_LOCALES))
ifneq (,$(extra_locales))
  ifneq ($(CALLED_FROM_SETUP),true)
    # Don't spam stdout, because envsetup.sh may be scraping values from it.
    $(info Adding CUSTOM_LOCALES [$(extra_locales)] to PRODUCT_LOCALES [$(PRODUCT_LOCALES)])
  endif
  PRODUCT_LOCALES += $(extra_locales)
  extra_locales :=
endif

# Add PRODUCT_LOCALES to PRODUCT_AAPT_CONFIG
PRODUCT_AAPT_CONFIG := $(strip $(PRODUCT_LOCALES) $(PRODUCTS.$(INTERNAL_PRODUCT).PRODUCT_AAPT_CONFIG))
PRODUCT_AAPT_PREF_CONFIG := $(strip $(PRODUCTS.$(INTERNAL_PRODUCT).PRODUCT_AAPT_PREF_CONFIG))
PRODUCT_AAPT_PREBUILT_DPI := $(strip $(PRODUCTS.$(INTERNAL_PRODUCT).PRODUCT_AAPT_PREBUILT_DPI))

# Keep a copy of the space-separated config
PRODUCT_AAPT_CONFIG_SP := $(PRODUCT_AAPT_CONFIG)

# Convert spaces to commas.
PRODUCT_AAPT_CONFIG := \
    $(subst $(space),$(comma),$(strip $(PRODUCT_AAPT_CONFIG)))

# product-scoped aapt flags
PRODUCT_AAPT_FLAGS :=
ifneq ($(filter en_XA ar_XB,$(PRODUCT_LOCALES)),)
# Force generating resources for pseudo-locales.
PRODUCT_AAPT_FLAGS += --pseudo-localize
endif

PRODUCT_BRAND := $(strip $(PRODUCTS.$(INTERNAL_PRODUCT).PRODUCT_BRAND))

PRODUCT_MODEL := $(strip $(PRODUCTS.$(INTERNAL_PRODUCT).PRODUCT_MODEL))
ifndef PRODUCT_MODEL
  PRODUCT_MODEL := $(strip $(PRODUCTS.$(INTERNAL_PRODUCT).PRODUCT_NAME))
endif

PRODUCT_MANUFACTURER := \
    $(strip $(PRODUCTS.$(INTERNAL_PRODUCT).PRODUCT_MANUFACTURER))
ifndef PRODUCT_MANUFACTURER
  PRODUCT_MANUFACTURER := unknown
endif

ifeq ($(PRODUCTS.$(INTERNAL_PRODUCT).PRODUCT_CHARACTERISTICS),)
  TARGET_AAPT_CHARACTERISTICS := default
else
  TARGET_AAPT_CHARACTERISTICS := $(strip $(PRODUCTS.$(INTERNAL_PRODUCT).PRODUCT_CHARACTERISTICS))
endif

PRODUCT_DEFAULT_WIFI_CHANNELS := \
    $(strip $(PRODUCTS.$(INTERNAL_PRODUCT).PRODUCT_DEFAULT_WIFI_CHANNELS))

PRODUCT_DEFAULT_DEV_CERTIFICATE := \
    $(strip $(PRODUCTS.$(INTERNAL_PRODUCT).PRODUCT_DEFAULT_DEV_CERTIFICATE))
ifdef PRODUCT_DEFAULT_DEV_CERTIFICATE
ifneq (1,$(words $(PRODUCT_DEFAULT_DEV_CERTIFICATE)))
    $(error PRODUCT_DEFAULT_DEV_CERTIFICATE='$(PRODUCT_DEFAULT_DEV_CERTIFICATE)', \
      only 1 certificate is allowed.)
endif
endif

# A list of words like <source path>:<destination path>[:<owner>].
# The file at the source path should be copied to the destination path
# when building this product. <destination path> is relative to
# $(PRODUCT_OUT), so it should look like, e.g., "system/etc/file.xml".
# The rules for these copy steps are defined in build/core/Makefile.
# The optional :<owner> is used to indicate the owner of a vendor file.
PRODUCT_COPY_FILES := \
    $(strip $(PRODUCTS.$(INTERNAL_PRODUCT).PRODUCT_COPY_FILES))

# A list of property assignments, like "key = value", with zero or more
# whitespace characters on either side of the '='.
PRODUCT_PROPERTY_OVERRIDES := \
    $(strip $(PRODUCTS.$(INTERNAL_PRODUCT).PRODUCT_PROPERTY_OVERRIDES))

# A list of property assignments, like "key = value", with zero or more
# whitespace characters on either side of the '='.
# used for adding properties to default.prop
PRODUCT_DEFAULT_PROPERTY_OVERRIDES := \
    $(strip $(PRODUCTS.$(INTERNAL_PRODUCT).PRODUCT_DEFAULT_PROPERTY_OVERRIDES))

# Should we use the default resources or add any product specific overlays
PRODUCT_PACKAGE_OVERLAYS := \
    $(strip $(PRODUCTS.$(INTERNAL_PRODUCT).PRODUCT_PACKAGE_OVERLAYS))
DEVICE_PACKAGE_OVERLAYS := \
        $(strip $(PRODUCTS.$(INTERNAL_PRODUCT).DEVICE_PACKAGE_OVERLAYS))

# The list of product-specific kernel header dirs
PRODUCT_VENDOR_KERNEL_HEADERS := \
    $(PRODUCTS.$(INTERNAL_PRODUCT).PRODUCT_VENDOR_KERNEL_HEADERS)

# Add the product-defined properties to the build properties.
ADDITIONAL_BUILD_PROPERTIES := \
    $(ADDITIONAL_BUILD_PROPERTIES) \
    $(PRODUCT_PROPERTY_OVERRIDES)

# The OTA key(s) specified by the product config, if any. The names
# of these keys are stored in the target-files zip so that post-build
# signing tools can substitute them for the test key embedded by
# default.
PRODUCT_OTA_PUBLIC_KEYS := $(sort \
    $(PRODUCTS.$(INTERNAL_PRODUCT).PRODUCT_OTA_PUBLIC_KEYS))

PRODUCT_EXTRA_RECOVERY_KEYS := $(sort \
    $(PRODUCTS.$(INTERNAL_PRODUCT).PRODUCT_EXTRA_RECOVERY_KEYS))

PRODUCT_DEX_PREOPT_DEFAULT_FLAGS := \
    $(strip $(PRODUCTS.$(INTERNAL_PRODUCT).PRODUCT_DEX_PREOPT_DEFAULT_FLAGS))
PRODUCT_DEX_PREOPT_BOOT_FLAGS := \
    $(strip $(PRODUCTS.$(INTERNAL_PRODUCT).PRODUCT_DEX_PREOPT_BOOT_FLAGS))
# Resolve and setup per-module dex-preopot configs.
PRODUCT_DEX_PREOPT_MODULE_CONFIGS := \
    $(strip $(PRODUCTS.$(INTERNAL_PRODUCT).PRODUCT_DEX_PREOPT_MODULE_CONFIGS))
# If a module has multiple setups, the first takes precedence.
_pdpmc_modules :=
$(foreach c,$(PRODUCT_DEX_PREOPT_MODULE_CONFIGS),\
  $(eval m := $(firstword $(subst =,$(space),$(c))))\
  $(if $(filter $(_pdpmc_modules),$(m)),,\
    $(eval _pdpmc_modules += $(m))\
    $(eval cf := $(patsubst $(m)=%,%,$(c)))\
    $(eval cf := $(subst $(_PDPMC_SP_PLACE_HOLDER),$(space),$(cf)))\
    $(eval DEXPREOPT.$(TARGET_PRODUCT).$(m).CONFIG := $(cf))))
_pdpmc_modules :=