core/node_fns.mk - platform/build - Git at Google

 #
 # Copyright (C) 2007 The Android Open Source Project
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
 # You may obtain a copy of the License at
 #
 #      http://www.apache.org/licenses/LICENSE-2.0
 #
 # Unless required by applicable law or agreed to in writing, software
 # distributed under the License is distributed on an "AS IS" BASIS,
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
 #

 #
 # Clears a list of variables using ":=".
 #
 # E.g.,
 #   $(call clear-var-list,A B C)
 # would be the same as:
 #   A :=
 #   B :=
 #   C :=
 #
 # $(1): list of variable names to clear
 #
 define clear-var-list
 $(foreach v,$(1),$(eval $(v):=))
 endef

 #
 # Copies a list of variables into another list of variables.
 # The target list is the same as the source list, but has
 # a dotted prefix affixed to it.
 #
 # E.g.,
 #   $(call copy-var-list, PREFIX, A B)
 # would be the same as:
 #   PREFIX.A := $(A)
 #   PREFIX.B := $(B)
 #
 # $(1): destination prefix
 # $(2): list of variable names to copy
 #
 define copy-var-list
 $(foreach v,$(2),$(eval $(strip $(1)).$(v):=$($(v))))
 endef

 #
 # Moves a list of variables into another list of variables.
 # The variable names differ by a prefix.  After moving, the
 # source variable is cleared.
 #
 # NOTE: Spaces are not allowed around the prefixes.
 #
 # E.g.,
 #   $(call move-var-list,SRC,DST,A B)
 # would be the same as:
 #   DST.A := $(SRC.A)
 #   SRC.A :=
 #   DST.B := $(SRC.B)
 #   SRC.B :=
 #
 # $(1): source prefix
 # $(2): destination prefix
 # $(3): list of variable names to move
 #
 define move-var-list
 $(foreach v,$(3), \
   $(eval $(2).$(v) := $($(1).$(v))) \
   $(eval $(1).$(v) :=) \
  )
 endef

 #
 # $(1): haystack
 # $(2): needle
 #
 # Guarantees that needle appears at most once in haystack,
 # without changing the order of other elements in haystack.
 # If needle appears multiple times, only the first occurrance
 # will survive.
 #
 define uniq-word
 $(strip \
   $(if $(filter-out 0 1,$(words $(filter $(2),$(1)))), \
     $(eval _uniq_word_seen :=) \
     $(foreach w,$(1), \
       $(if $(filter $(2),$(w)), \
         $(if $(_uniq_word_seen),, \
           $(w) \
           $(eval _uniq_word_seen := true)), \
         $(w))), \
   $(1)))
 endef

 INHERIT_TAG := @inherit:

 #
 # Walks through the list of variables, each qualified by the prefix,
 # and finds instances of words beginning with INHERIT_TAG.  Scrape
 # off INHERIT_TAG from each matching word, and return the sorted,
 # unique set of those words.
 #
 # E.g., given
 #   PREFIX.A := A $(INHERIT_TAG)aaa B C
 #   PREFIX.B := B $(INHERIT_TAG)aaa C $(INHERIT_TAG)bbb D E
 # Then
 #   $(call get-inherited-nodes,PREFIX,A B)
 # returns
 #   aaa bbb
 #
 # $(1): variable prefix
 # $(2): list of variables to check
 #
 define get-inherited-nodes
 $(sort \
   $(subst $(INHERIT_TAG),, \
     $(filter $(INHERIT_TAG)%, \
       $(foreach v,$(2),$($(1).$(v))) \
  )))
 endef

 #
 # for each variable ( (prefix + name) * vars ):
 #   get list of inherited words; if not empty:
 #     for each inherit:
 #       replace the first occurrence with (prefix + inherited + var)
 #       clear the source var so we can't inherit the value twice
 #
 # $(1): context prefix
 # $(2): name of this node
 # $(3): list of node variable names
 # $(4): list of single value variable names (subset of $(3))
 #
 define _expand-inherited-values
   $(foreach v,$(3), \
     $(eval ### "Shorthand for the name of the target variable") \
     $(eval _eiv_tv := $(1).$(2).$(v)) \
     $(eval ### "Get the list of nodes that this variable inherits") \
     $(eval _eiv_i := \
         $(sort \
             $(patsubst $(INHERIT_TAG)%,%, \
                 $(filter $(INHERIT_TAG)%, $($(_eiv_tv)) \
      )))) \
     $(eval ### "Whether this variable should only take a single value") \
     $(eval _eiv_sv := $(filter $(v),$(4))) \
     $(foreach i,$(_eiv_i), \
       $(eval ### "Make sure that this inherit appears only once") \
       $(eval $(_eiv_tv) := \
           $(call uniq-word,$($(_eiv_tv)),$(INHERIT_TAG)$(i))) \
       $(eval ### "The expanded value, empty if we want a single value and have one") \
       $(eval _eiv_ev := \
         $(if $(and $(_eiv_sv),$(filter-out $(INHERIT_TAG)%,$($(_eiv_tv)))),,\
           $($(1).$(i).$(v)) \
         ) \
       ) \
       $(eval ### "Expand the inherit tag") \
       $(eval $(_eiv_tv) := \
           $(strip $(patsubst $(INHERIT_TAG)$(i),$(_eiv_ev),$($(_eiv_tv))))) \
       $(eval ### "Clear the child so DAGs don't create duplicate entries" ) \
       $(eval $(1).$(i).$(v) :=) \
       $(eval ### "If we just inherited ourselves, it's a cycle.") \
       $(if $(filter $(INHERIT_TAG)$(2),$($(_eiv_tv))), \
         $(warning Cycle detected between "$(2)" and "$(i)" for context "$(1)") \
         $(error import of "$(2)" failed) \
       ) \
      ) \
    ) \
    $(eval _eiv_tv :=) \
    $(eval _eiv_i :=)
 endef

 #
 # $(1): context prefix
 # $(2): makefile representing this node
 # $(3): list of node variable names
 # $(4): list of single value variable names (subset of $(3))
 #
 # _include_stack contains the list of included files, with the most recent files first.
 define _import-node
   $(eval _include_stack := $(2) $$(_include_stack))
   $(call clear-var-list, $(3))
   $(eval LOCAL_PATH := $(patsubst %/,%,$(dir $(2))))
   $(eval MAKEFILE_LIST :=)
   $(call dump-import-start,$(_include_stack))
   $(call dump-config-vals,$(2),before)
   $(eval include $(2))
   $(call dump-import-done,$(_include_stack))
   $(call dump-config-vals,$(2),after)
   $(eval _included := $(filter-out $(2),$(MAKEFILE_LIST)))
   $(eval MAKEFILE_LIST :=)
   $(eval LOCAL_PATH :=)
   $(call copy-var-list, $(1).$(2), $(3))
   $(call clear-var-list, $(3))

   $(eval $(1).$(2).inherited := \
       $(call get-inherited-nodes,$(1).$(2),$(3)))
   $(call _import-nodes-inner,$(1),$($(1).$(2).inherited),$(3),$(4))

   $(call _expand-inherited-values,$(1),$(2),$(3),$(4))

   $(eval $(1).$(2).inherited :=)
   $(eval _include_stack := $(wordlist 2,9999,$$(_include_stack)))
 endef

 #
 # This will generate a warning for _included above
 #  $(if $(_included), \
 #      $(eval $(warning product spec file: $(2)))\
 #      $(foreach _inc,$(_included),$(eval $(warning $(space)$(space)$(space)includes: $(_inc)))),)
 #

 #
 # $(1): context prefix
 # $(2): list of makefiles representing nodes to import
 # $(3): list of node variable names
 # $(4): list of single value variable names (subset of $(3))
 #
 #TODO: Make the "does not exist" message more helpful;
 #      should print out the name of the file trying to include it.
 define _import-nodes-inner
   $(foreach _in,$(2), \
     $(if $(wildcard $(_in)), \
       $(if $($(1).$(_in).seen), \
         $(eval ### "skipping already-imported $(_in)") \
        , \
         $(eval $(1).$(_in).seen := true) \
         $(call _import-node,$(1),$(strip $(_in)),$(3),$(4)) \
        ) \
      , \
       $(error $(1): "$(_in)" does not exist) \
      ) \
    )
 endef

 #
 # $(1): output list variable name, like "PRODUCTS" or "DEVICES"
 # $(2): list of makefiles representing nodes to import
 # $(3): list of node variable names
 # $(4): list with subset of variable names that take only a single value, instead
 #       of the default list semantics
 #
 define import-nodes
 $(call dump-phase-start,$(1),$(2),$(3),$(4),build/make/core/node_fns.mk) \
 $(if \
   $(foreach _in,$(2), \
     $(eval _node_import_context := _nic.$(1).[[$(_in)]]) \
     $(if $(_include_stack),$(eval $(error ASSERTION FAILED: _include_stack \
                 should be empty here: $(_include_stack))),) \
     $(eval _include_stack := ) \
     $(call _import-nodes-inner,$(_node_import_context),$(_in),$(3),$(4)) \
     $(call move-var-list,$(_node_import_context).$(_in),$(1).$(_in),$(3)) \
     $(eval _node_import_context :=) \
     $(eval $(1) := $($(1)) $(_in)) \
     $(if $(_include_stack),$(eval $(error ASSERTION FAILED: _include_stack \
                 should be empty here: $(_include_stack))),) \
    ) \
 ,) \
 $(call dump-phase-end,build/make/core/node_fns.mk)
 endef
	#
	# Copyright (C) 2007 The Android Open Source Project
	#
	# Licensed under the Apache License, Version 2.0 (the "License");
	# you may not use this file except in compliance with the License.
	# You may obtain a copy of the License at
	#
	# http://www.apache.org/licenses/LICENSE-2.0
	#
	# Unless required by applicable law or agreed to in writing, software
	# distributed under the License is distributed on an "AS IS" BASIS,
	# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	# See the License for the specific language governing permissions and
	# limitations under the License.
	#

	#
	# Clears a list of variables using ":=".
	#
	# E.g.,
	# $(call clear-var-list,A B C)
	# would be the same as:
	# A :=
	# B :=
	# C :=
	#
	# $(1): list of variable names to clear
	#
	define clear-var-list
	$(foreach v,$(1),$(eval $(v):=))
	endef

	#
	# Copies a list of variables into another list of variables.
	# The target list is the same as the source list, but has
	# a dotted prefix affixed to it.
	#
	# E.g.,
	# $(call copy-var-list, PREFIX, A B)
	# would be the same as:
	# PREFIX.A := $(A)
	# PREFIX.B := $(B)
	#
	# $(1): destination prefix
	# $(2): list of variable names to copy
	#
	define copy-var-list
	$(foreach v,$(2),$(eval $(strip $(1)).$(v):=$($(v))))
	endef

	#
	# Moves a list of variables into another list of variables.
	# The variable names differ by a prefix. After moving, the
	# source variable is cleared.
	#
	# NOTE: Spaces are not allowed around the prefixes.
	#
	# E.g.,
	# $(call move-var-list,SRC,DST,A B)
	# would be the same as:
	# DST.A := $(SRC.A)
	# SRC.A :=
	# DST.B := $(SRC.B)
	# SRC.B :=
	#
	# $(1): source prefix
	# $(2): destination prefix
	# $(3): list of variable names to move
	#
	define move-var-list
	$(foreach v,$(3), \
	$(eval $(2).$(v) := $($(1).$(v))) \
	$(eval $(1).$(v) :=) \
	)
	endef

	#
	# $(1): haystack
	# $(2): needle
	#
	# Guarantees that needle appears at most once in haystack,
	# without changing the order of other elements in haystack.
	# If needle appears multiple times, only the first occurrance
	# will survive.
	#
	define uniq-word
	$(strip \
	$(if $(filter-out 0 1,$(words $(filter $(2),$(1)))), \
	$(eval _uniq_word_seen :=) \
	$(foreach w,$(1), \
	$(if $(filter $(2),$(w)), \
	$(if $(_uniq_word_seen),, \
	$(w) \
	$(eval _uniq_word_seen := true)), \
	$(w))), \
	$(1)))
	endef

	INHERIT_TAG := @inherit:

	#
	# Walks through the list of variables, each qualified by the prefix,
	# and finds instances of words beginning with INHERIT_TAG. Scrape
	# off INHERIT_TAG from each matching word, and return the sorted,
	# unique set of those words.
	#
	# E.g., given
	# PREFIX.A := A $(INHERIT_TAG)aaa B C
	# PREFIX.B := B $(INHERIT_TAG)aaa C $(INHERIT_TAG)bbb D E
	# Then
	# $(call get-inherited-nodes,PREFIX,A B)
	# returns
	# aaa bbb
	#
	# $(1): variable prefix
	# $(2): list of variables to check
	#
	define get-inherited-nodes
	$(sort \
	$(subst $(INHERIT_TAG),, \
	$(filter $(INHERIT_TAG)%, \
	$(foreach v,$(2),$($(1).$(v))) \
	)))
	endef

	#
	# for each variable ( (prefix + name) * vars ):
	# get list of inherited words; if not empty:
	# for each inherit:
	# replace the first occurrence with (prefix + inherited + var)
	# clear the source var so we can't inherit the value twice
	#
	# $(1): context prefix
	# $(2): name of this node
	# $(3): list of node variable names
	# $(4): list of single value variable names (subset of $(3))
	#
	define _expand-inherited-values
	$(foreach v,$(3), \
	$(eval ### "Shorthand for the name of the target variable") \
	$(eval _eiv_tv := $(1).$(2).$(v)) \
	$(eval ### "Get the list of nodes that this variable inherits") \
	$(eval _eiv_i := \
	$(sort \
	$(patsubst $(INHERIT_TAG)%,%, \
	$(filter $(INHERIT_TAG)%, $($(_eiv_tv)) \
	)))) \
	$(eval ### "Whether this variable should only take a single value") \
	$(eval _eiv_sv := $(filter $(v),$(4))) \
	$(foreach i,$(_eiv_i), \
	$(eval ### "Make sure that this inherit appears only once") \
	$(eval $(_eiv_tv) := \
	$(call uniq-word,$($(_eiv_tv)),$(INHERIT_TAG)$(i))) \
	$(eval ### "The expanded value, empty if we want a single value and have one") \
	$(eval _eiv_ev := \
	$(if $(and $(_eiv_sv),$(filter-out $(INHERIT_TAG)%,$($(_eiv_tv)))),,\
	$($(1).$(i).$(v)) \
	) \
	) \
	$(eval ### "Expand the inherit tag") \
	$(eval $(_eiv_tv) := \
	$(strip $(patsubst $(INHERIT_TAG)$(i),$(_eiv_ev),$($(_eiv_tv))))) \
	$(eval ### "Clear the child so DAGs don't create duplicate entries" ) \
	$(eval $(1).$(i).$(v) :=) \
	$(eval ### "If we just inherited ourselves, it's a cycle.") \
	$(if $(filter $(INHERIT_TAG)$(2),$($(_eiv_tv))), \
	$(warning Cycle detected between "$(2)" and "$(i)" for context "$(1)") \
	$(error import of "$(2)" failed) \
	) \
	) \
	) \
	$(eval _eiv_tv :=) \
	$(eval _eiv_i :=)
	endef

	#
	# $(1): context prefix
	# $(2): makefile representing this node
	# $(3): list of node variable names
	# $(4): list of single value variable names (subset of $(3))
	#
	# _include_stack contains the list of included files, with the most recent files first.
	define _import-node
	$(eval _include_stack := $(2) $$(_include_stack))
	$(call clear-var-list, $(3))
	$(eval LOCAL_PATH := $(patsubst %/,%,$(dir $(2))))
	$(eval MAKEFILE_LIST :=)
	$(call dump-import-start,$(_include_stack))
	$(call dump-config-vals,$(2),before)
	$(eval include $(2))
	$(call dump-import-done,$(_include_stack))
	$(call dump-config-vals,$(2),after)
	$(eval _included := $(filter-out $(2),$(MAKEFILE_LIST)))
	$(eval MAKEFILE_LIST :=)
	$(eval LOCAL_PATH :=)
	$(call copy-var-list, $(1).$(2), $(3))
	$(call clear-var-list, $(3))

	$(eval $(1).$(2).inherited := \
	$(call get-inherited-nodes,$(1).$(2),$(3)))
	$(call _import-nodes-inner,$(1),$($(1).$(2).inherited),$(3),$(4))

	$(call _expand-inherited-values,$(1),$(2),$(3),$(4))

	$(eval $(1).$(2).inherited :=)
	$(eval _include_stack := $(wordlist 2,9999,$$(_include_stack)))
	endef

	#
	# This will generate a warning for _included above
	# $(if $(_included), \
	# $(eval $(warning product spec file: $(2)))\
	# $(foreach _inc,$(_included),$(eval $(warning $(space)$(space)$(space)includes: $(_inc)))),)
	#

	#
	# $(1): context prefix
	# $(2): list of makefiles representing nodes to import
	# $(3): list of node variable names
	# $(4): list of single value variable names (subset of $(3))
	#
	#TODO: Make the "does not exist" message more helpful;
	# should print out the name of the file trying to include it.
	define _import-nodes-inner
	$(foreach _in,$(2), \
	$(if $(wildcard $(_in)), \
	$(if $($(1).$(_in).seen), \
	$(eval ### "skipping already-imported $(_in)") \
	, \
	$(eval $(1).$(_in).seen := true) \
	$(call _import-node,$(1),$(strip $(_in)),$(3),$(4)) \
	) \
	, \
	$(error $(1): "$(_in)" does not exist) \
	) \
	)
	endef

	#
	# $(1): output list variable name, like "PRODUCTS" or "DEVICES"
	# $(2): list of makefiles representing nodes to import
	# $(3): list of node variable names
	# $(4): list with subset of variable names that take only a single value, instead
	# of the default list semantics
	#
	define import-nodes
	$(call dump-phase-start,$(1),$(2),$(3),$(4),build/make/core/node_fns.mk) \
	$(if \
	$(foreach _in,$(2), \
	$(eval _node_import_context := _nic.$(1).[[$(_in)]]) \
	$(if $(_include_stack),$(eval $(error ASSERTION FAILED: _include_stack \
	should be empty here: $(_include_stack))),) \
	$(eval _include_stack := ) \
	$(call _import-nodes-inner,$(_node_import_context),$(_in),$(3),$(4)) \
	$(call move-var-list,$(_node_import_context).$(_in),$(1).$(_in),$(3)) \
	$(eval _node_import_context :=) \
	$(eval $(1) := $($(1)) $(_in)) \
	$(if $(_include_stack),$(eval $(error ASSERTION FAILED: _include_stack \
	should be empty here: $(_include_stack))),) \
	) \
	,) \
	$(call dump-phase-end,build/make/core/node_fns.mk)
	endef