1# 2# Copyright (C) 2007 The Android Open Source Project 3# 4# Licensed under the Apache License, Version 2.0 (the "License"); 5# you may not use this file except in compliance with the License. 6# You may obtain a copy of the License at 7# 8# http://www.apache.org/licenses/LICENSE-2.0 9# 10# Unless required by applicable law or agreed to in writing, software 11# distributed under the License is distributed on an "AS IS" BASIS, 12# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13# See the License for the specific language governing permissions and 14# limitations under the License. 15# 16 17# 18# Clears a list of variables using ":=". 19# 20# E.g., 21# $(call clear-var-list,A B C) 22# would be the same as: 23# A := 24# B := 25# C := 26# 27# $(1): list of variable names to clear 28# 29define clear-var-list 30$(foreach v,$(1),$(eval $(v):=)) 31endef 32 33# 34# Copies a list of variables into another list of variables. 35# The target list is the same as the source list, but has 36# a dotted prefix affixed to it. 37# 38# E.g., 39# $(call copy-var-list, PREFIX, A B) 40# would be the same as: 41# PREFIX.A := $(A) 42# PREFIX.B := $(B) 43# 44# $(1): destination prefix 45# $(2): list of variable names to copy 46# 47define copy-var-list 48$(foreach v,$(2),$(eval $(strip $(1)).$(v):=$($(v)))) 49endef 50 51# 52# Moves a list of variables into another list of variables. 53# The variable names differ by a prefix. After moving, the 54# source variable is cleared. 55# 56# NOTE: Spaces are not allowed around the prefixes. 57# 58# E.g., 59# $(call move-var-list,SRC,DST,A B) 60# would be the same as: 61# DST.A := $(SRC.A) 62# SRC.A := 63# DST.B := $(SRC.B) 64# SRC.B := 65# 66# $(1): source prefix 67# $(2): destination prefix 68# $(3): list of variable names to move 69# 70define move-var-list 71$(foreach v,$(3), \ 72 $(eval $(2).$(v) := $($(1).$(v))) \ 73 $(eval $(1).$(v) :=) \ 74 ) 75endef 76 77# 78# $(1): haystack 79# $(2): needle 80# 81# Guarantees that needle appears at most once in haystack, 82# without changing the order of other elements in haystack. 83# If needle appears multiple times, only the first occurrance 84# will survive. 85# 86# How it works: 87# 88# - Stick everything in haystack into a single word, 89# with "|||" separating the words. 90# - Replace occurrances of "|||$(needle)|||" with "||| |||", 91# breaking haystack back into multiple words, with spaces 92# where needle appeared. 93# - Add needle between the first and second words of haystack. 94# - Replace "|||" with spaces, breaking haystack back into 95# individual words. 96# 97empty := 98space := $(empty) $(empty) 99define uniq-word 100$(strip \ 101 $(if $(filter $(2),$(1)), \ 102 $(eval h := |||$(subst $(space),|||,$(strip $(1)))|||) \ 103 $(eval h := $(subst |||$(strip $(2))|||,|||$(space)|||,$(h))) \ 104 $(eval h := $(word 1,$(h)) $(2) $(wordlist 2,9999,$(h))) \ 105 $(subst |||,$(space),$(h)) \ 106 , \ 107 $(1) \ 108 )) 109endef 110 111INHERIT_TAG := @inherit: 112 113# 114# Walks through the list of variables, each qualified by the prefix, 115# and finds instances of words beginning with INHERIT_TAG. Scrape 116# off INHERIT_TAG from each matching word, and return the sorted, 117# unique set of those words. 118# 119# E.g., given 120# PREFIX.A := A $(INHERIT_TAG)aaa B C 121# PREFIX.B := B $(INHERIT_TAG)aaa C $(INHERIT_TAG)bbb D E 122# Then 123# $(call get-inherited-nodes,PREFIX,A B) 124# returns 125# aaa bbb 126# 127# $(1): variable prefix 128# $(2): list of variables to check 129# 130define get-inherited-nodes 131$(sort \ 132 $(subst $(INHERIT_TAG),, \ 133 $(filter $(INHERIT_TAG)%, \ 134 $(foreach v,$(2),$($(1).$(v))) \ 135 ))) 136endef 137 138# 139# for each variable ( (prefix + name) * vars ): 140# get list of inherited words; if not empty: 141# for each inherit: 142# replace the first occurrence with (prefix + inherited + var) 143# clear the source var so we can't inherit the value twice 144# 145# $(1): context prefix 146# $(2): name of this node 147# $(3): list of variable names 148# 149define _expand-inherited-values 150 $(foreach v,$(3), \ 151 $(eval ### "Shorthand for the name of the target variable") \ 152 $(eval _eiv_tv := $(1).$(2).$(v)) \ 153 $(eval ### "Get the list of nodes that this variable inherits") \ 154 $(eval _eiv_i := \ 155 $(sort \ 156 $(patsubst $(INHERIT_TAG)%,%, \ 157 $(filter $(INHERIT_TAG)%, $($(_eiv_tv)) \ 158 )))) \ 159 $(foreach i,$(_eiv_i), \ 160 $(eval ### "Make sure that this inherit appears only once") \ 161 $(eval $(_eiv_tv) := \ 162 $(call uniq-word,$($(_eiv_tv)),$(INHERIT_TAG)$(i))) \ 163 $(eval ### "Expand the inherit tag") \ 164 $(eval $(_eiv_tv) := \ 165 $(strip \ 166 $(patsubst $(INHERIT_TAG)$(i),$($(1).$(i).$(v)), \ 167 $($(_eiv_tv))))) \ 168 $(eval ### "Clear the child so DAGs don't create duplicate entries" ) \ 169 $(eval $(1).$(i).$(v) :=) \ 170 $(eval ### "If we just inherited ourselves, it's a cycle.") \ 171 $(if $(filter $(INHERIT_TAG)$(2),$($(_eiv_tv))), \ 172 $(warning Cycle detected between "$(2)" and "$(i)" for context "$(1)") \ 173 $(error import of "$(2)" failed) \ 174 ) \ 175 ) \ 176 ) \ 177 $(eval _eiv_tv :=) \ 178 $(eval _eiv_i :=) 179endef 180 181# 182# $(1): context prefix 183# $(2): makefile representing this node 184# $(3): list of node variable names 185# 186# _include_stack contains the list of included files, with the most recent files first. 187define _import-node 188 $(eval _include_stack := $(2) $$(_include_stack)) 189 $(call clear-var-list, $(3)) 190 $(eval LOCAL_PATH := $(patsubst %/,%,$(dir $(2)))) 191 $(eval MAKEFILE_LIST :=) 192 $(eval include $(2)) 193 $(eval _included := $(filter-out $(2),$(MAKEFILE_LIST))) 194 $(eval MAKEFILE_LIST :=) 195 $(eval LOCAL_PATH :=) 196 $(call copy-var-list, $(1).$(2), $(3)) 197 $(call clear-var-list, $(3)) 198 199 $(eval $(1).$(2).inherited := \ 200 $(call get-inherited-nodes,$(1).$(2),$(3))) 201 $(call _import-nodes-inner,$(1),$($(1).$(2).inherited),$(3)) 202 203 $(call _expand-inherited-values,$(1),$(2),$(3)) 204 205 $(eval $(1).$(2).inherited :=) 206 $(eval _include_stack := $(wordlist 2,9999,$$(_include_stack))) 207endef 208 209# 210# This will generate a warning for _included above 211# $(if $(_included), \ 212# $(eval $(warning product spec file: $(2)))\ 213# $(foreach _inc,$(_included),$(eval $(warning $(space)$(space)$(space)includes: $(_inc)))),) 214# 215 216# 217# $(1): context prefix 218# $(2): list of makefiles representing nodes to import 219# $(3): list of node variable names 220# 221#TODO: Make the "does not exist" message more helpful; 222# should print out the name of the file trying to include it. 223define _import-nodes-inner 224 $(foreach _in,$(2), \ 225 $(if $(wildcard $(_in)), \ 226 $(if $($(1).$(_in).seen), \ 227 $(eval ### "skipping already-imported $(_in)") \ 228 , \ 229 $(eval $(1).$(_in).seen := true) \ 230 $(call _import-node,$(1),$(strip $(_in)),$(3)) \ 231 ) \ 232 , \ 233 $(error $(1): "$(_in)" does not exist) \ 234 ) \ 235 ) 236endef 237 238# 239# $(1): output list variable name, like "PRODUCTS" or "DEVICES" 240# $(2): list of makefiles representing nodes to import 241# $(3): list of node variable names 242# 243define import-nodes 244$(if \ 245 $(foreach _in,$(2), \ 246 $(eval _node_import_context := _nic.$(1).[[$(_in)]]) \ 247 $(if $(_include_stack),$(eval $(error ASSERTION FAILED: _include_stack \ 248 should be empty here: $(_include_stack))),) \ 249 $(eval _include_stack := ) \ 250 $(call _import-nodes-inner,$(_node_import_context),$(_in),$(3)) \ 251 $(call move-var-list,$(_node_import_context).$(_in),$(1).$(_in),$(3)) \ 252 $(eval _node_import_context :=) \ 253 $(eval $(1) := $($(1)) $(_in)) \ 254 $(if $(_include_stack),$(eval $(error ASSERTION FAILED: _include_stack \ 255 should be empty here: $(_include_stack))),) \ 256 ) \ 257,) 258endef 259