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 # 29 define clear-var-list 30 $(foreach v,$(1),$(eval $(v):=)) 31 endef 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 # 47 define copy-var-list 48 $(foreach v,$(2),$(eval $(strip $(1)).$(v):=$($(v)))) 49 endef 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 # 70 define move-var-list 71 $(foreach v,$(3), \ 72 $(eval $(2).$(v) := $($(1).$(v))) \ 73 $(eval $(1).$(v) :=) \ 74 ) 75 endef 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 # 97 empty := 98 space := $(empty) $(empty) 99 define 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 )) 109 endef 110 111 INHERIT_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 # 130 define get-inherited-nodes 131 $(sort \ 132 $(subst $(INHERIT_TAG),, \ 133 $(filter $(INHERIT_TAG)%, \ 134 $(foreach v,$(2),$($(1).$(v))) \ 135 ))) 136 endef 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 # 149 define _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 :=) 179 endef 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. 187 define _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))) 207 endef 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. 223 define _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 ) 236 endef 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 # 243 define 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 ,) 258 endef 259
