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Sam Ravnborg8ec4b4f2005-07-25 20:10:36 +00001####
2# kbuild: Generic definitions
3
Roman Zippelbeda9f32007-02-08 22:48:51 +01004# Convenient variables
Sam Ravnborg8ec4b4f2005-07-25 20:10:36 +00005comma := ,
Masahiro Yamada13338932014-03-20 11:08:20 +09006quote := "
Sam Ravnborgd51bfb72006-01-06 22:35:59 +01007squote := '
Sam Ravnborg8ec4b4f2005-07-25 20:10:36 +00008empty :=
9space := $(empty) $(empty)
Masahiro Yamada9c8fa9b2016-05-07 15:48:26 +090010space_escape := _-_SPACE_-_
Sam Ravnborg8ec4b4f2005-07-25 20:10:36 +000011
12###
Sam Ravnborg48f1f052006-07-23 19:37:44 +020013# Name of target with a '.' as filename prefix. foo/bar.o => foo/.bar.o
14dot-target = $(dir $@).$(notdir $@)
15
16###
Sam Ravnborg8ec4b4f2005-07-25 20:10:36 +000017# The temporary file to save gcc -MD generated dependencies must not
18# contain a comma
Sam Ravnborg48f1f052006-07-23 19:37:44 +020019depfile = $(subst $(comma),_,$(dot-target).d)
Sam Ravnborg8ec4b4f2005-07-25 20:10:36 +000020
21###
Sam Ravnborg5e8d7802006-07-01 09:58:02 +020022# filename of target with directory and extension stripped
23basetarget = $(basename $(notdir $@))
24
25###
Arnaud Lacombee0318d82011-06-01 17:50:25 -040026# filename of first prerequisite with directory and extension stripped
27baseprereq = $(basename $(notdir $<))
28
29###
Sam Ravnborgd51bfb72006-01-06 22:35:59 +010030# Escape single quote for use in echo statements
31escsq = $(subst $(squote),'\$(squote)',$1)
32
33###
Mike Frysinger5410ecc2008-11-06 03:31:34 -050034# Easy method for doing a status message
35 kecho := :
36 quiet_kecho := echo
37silent_kecho := :
38kecho := $($(quiet)kecho)
39
40###
Sam Ravnborg8ec4b4f2005-07-25 20:10:36 +000041# filechk is used to check if the content of a generated file is updated.
42# Sample usage:
43# define filechk_sample
44# echo $KERNELRELEASE
45# endef
46# version.h : Makefile
47# $(call filechk,sample)
48# The rule defined shall write to stdout the content of the new file.
49# The existing file will be compared with the new one.
50# - If no file exist it is created
51# - If the content differ the new file is used
52# - If they are equal no change, and no timestamp update
53# - stdin is piped in from the first prerequisite ($<) so one has
54# to specify a valid file as first prerequisite (often the kbuild file)
55define filechk
56 $(Q)set -e; \
Mike Frysingerfd54f502008-11-06 03:31:35 -050057 $(kecho) ' CHK $@'; \
Sam Ravnborg8ec4b4f2005-07-25 20:10:36 +000058 mkdir -p $(dir $@); \
59 $(filechk_$(1)) < $< > $@.tmp; \
60 if [ -r $@ ] && cmp -s $@ $@.tmp; then \
61 rm -f $@.tmp; \
62 else \
Mike Frysingerfd54f502008-11-06 03:31:35 -050063 $(kecho) ' UPD $@'; \
Sam Ravnborg8ec4b4f2005-07-25 20:10:36 +000064 mv -f $@.tmp $@; \
65 fi
66endef
67
Sam Ravnborg20a468b2006-01-22 13:34:15 +010068######
Sam Ravnborg9d6e7a72006-02-18 10:03:40 +010069# gcc support functions
Sam Ravnborg20a468b2006-01-22 13:34:15 +010070# See documentation in Documentation/kbuild/makefiles.txt
71
Sam Ravnborg910b4042007-10-19 21:46:01 +020072# cc-cross-prefix
73# Usage: CROSS_COMPILE := $(call cc-cross-prefix, m68k-linux-gnu- m68k-linux-)
74# Return first prefix where a prefix$(CC) is found in PATH.
75# If no $(CC) found in PATH with listed prefixes return nothing
76cc-cross-prefix = \
77 $(word 1, $(foreach c,$(1), \
78 $(shell set -e; \
79 if (which $(strip $(c))$(CC)) > /dev/null 2>&1 ; then \
80 echo $(c); \
81 fi)))
82
Roman Zippelbeda9f32007-02-08 22:48:51 +010083# output directory for tests below
84TMPOUT := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/)
85
86# try-run
87# Usage: option = $(call try-run, $(CC)...-o "$$TMP",option-ok,otherwise)
88# Exit code chooses option. "$$TMP" is can be used as temporary file and
89# is automatically cleaned up.
90try-run = $(shell set -e; \
91 TMP="$(TMPOUT).$$$$.tmp"; \
Sam Ravnborg691ef3e2009-09-19 10:31:45 +020092 TMPO="$(TMPOUT).$$$$.o"; \
Roman Zippelbeda9f32007-02-08 22:48:51 +010093 if ($(1)) >/dev/null 2>&1; \
94 then echo "$(2)"; \
95 else echo "$(3)"; \
96 fi; \
Sam Ravnborg691ef3e2009-09-19 10:31:45 +020097 rm -f "$$TMP" "$$TMPO")
Roman Zippel347a00f2006-12-10 02:18:41 -080098
Sam Ravnborg20a468b2006-01-22 13:34:15 +010099# as-option
Oleg Verychbff288c2007-02-07 23:04:35 +0100100# Usage: cflags-y += $(call as-option,-Wa$(comma)-isa=foo,)
Roman Zippelbeda9f32007-02-08 22:48:51 +0100101
102as-option = $(call try-run,\
Jean Delvareb1e0d8b2012-10-02 16:42:36 +0200103 $(CC) $(KBUILD_CFLAGS) $(1) -c -x assembler /dev/null -o "$$TMP",$(1),$(2))
Sam Ravnborg20a468b2006-01-22 13:34:15 +0100104
Andi Kleene2414912006-09-26 10:52:30 +0200105# as-instr
Oleg Verychbff288c2007-02-07 23:04:35 +0100106# Usage: cflags-y += $(call as-instr,instr,option1,option2)
Roman Zippelbeda9f32007-02-08 22:48:51 +0100107
108as-instr = $(call try-run,\
Jean Delvareb1e0d8b2012-10-02 16:42:36 +0200109 printf "%b\n" "$(1)" | $(CC) $(KBUILD_AFLAGS) -c -x assembler -o "$$TMP" -,$(2),$(3))
Andi Kleene2414912006-09-26 10:52:30 +0200110
Sam Ravnborg20a468b2006-01-22 13:34:15 +0100111# cc-option
Oleg Verychbff288c2007-02-07 23:04:35 +0100112# Usage: cflags-y += $(call cc-option,-march=winchip-c6,-march=i586)
Roman Zippelbeda9f32007-02-08 22:48:51 +0100113
114cc-option = $(call try-run,\
Jean Delvareb1e0d8b2012-10-02 16:42:36 +0200115 $(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",$(1),$(2))
Sam Ravnborg20a468b2006-01-22 13:34:15 +0100116
117# cc-option-yn
Oleg Verychbff288c2007-02-07 23:04:35 +0100118# Usage: flag := $(call cc-option-yn,-march=winchip-c6)
Roman Zippelbeda9f32007-02-08 22:48:51 +0100119cc-option-yn = $(call try-run,\
Jean Delvareb1e0d8b2012-10-02 16:42:36 +0200120 $(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",y,n)
Sam Ravnborg20a468b2006-01-22 13:34:15 +0100121
122# cc-option-align
123# Prefix align with either -falign or -malign
124cc-option-align = $(subst -functions=0,,\
Roman Zippelbeda9f32007-02-08 22:48:51 +0100125 $(call cc-option,-falign-functions=0,-malign-functions=0))
Sam Ravnborg20a468b2006-01-22 13:34:15 +0100126
Michal Marek8417da6f2011-05-02 12:51:15 +0200127# cc-disable-warning
128# Usage: cflags-y += $(call cc-disable-warning,unused-but-set-variable)
129cc-disable-warning = $(call try-run,\
Jean Delvareb1e0d8b2012-10-02 16:42:36 +0200130 $(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) -W$(strip $(1)) -c -x c /dev/null -o "$$TMP",-Wno-$(strip $(1)))
Michal Marek8417da6f2011-05-02 12:51:15 +0200131
Michal Marek5631d9c2015-08-19 17:36:41 +0200132# cc-name
133# Expands to either gcc or clang
134cc-name = $(shell $(CC) -v 2>&1 | grep -q "clang version" && echo clang || echo gcc)
135
Sam Ravnborg20a468b2006-01-22 13:34:15 +0100136# cc-version
Sam Ravnborg8eb3afe2006-07-23 19:49:45 +0200137cc-version = $(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-version.sh $(CC))
Sam Ravnborg20a468b2006-01-22 13:34:15 +0100138
Segher Boessenkool0ab2a272007-05-19 18:49:07 +0200139# cc-fullversion
Segher Boessenkool0ab2a272007-05-19 18:49:07 +0200140cc-fullversion = $(shell $(CONFIG_SHELL) \
141 $(srctree)/scripts/gcc-version.sh -p $(CC))
142
Sam Ravnborg20a468b2006-01-22 13:34:15 +0100143# cc-ifversion
144# Usage: EXTRA_CFLAGS += $(call cc-ifversion, -lt, 0402, -O1)
Masahiro Yamada6dcb4e52014-12-25 14:31:27 +0900145cc-ifversion = $(shell [ $(cc-version) $(1) $(2) ] && echo $(3) || echo $(4))
Sam Ravnborg20a468b2006-01-22 13:34:15 +0100146
Sam Ravnborgf86fd302009-09-19 10:14:33 +0200147# cc-ldoption
148# Usage: ldflags += $(call cc-ldoption, -Wl$(comma)--hash-style=both)
149cc-ldoption = $(call try-run,\
Jean Delvareb1e0d8b2012-10-02 16:42:36 +0200150 $(CC) $(1) -nostdlib -x c /dev/null -o "$$TMP",$(1),$(2))
Roland McGrath0b0bf7a2006-07-30 03:04:06 -0700151
Sam Ravnborg691ef3e2009-09-19 10:31:45 +0200152# ld-option
153# Usage: LDFLAGS += $(call ld-option, -X)
154ld-option = $(call try-run,\
Antony Pavlov5b83df22013-04-03 18:42:33 +0400155 $(CC) -x c /dev/null -c -o "$$TMPO" ; $(LD) $(1) "$$TMPO" -o "$$TMP",$(1),$(2))
Sam Ravnborg691ef3e2009-09-19 10:31:45 +0200156
Michal Marek40df7592011-04-20 13:45:30 +0200157# ar-option
158# Usage: KBUILD_ARFLAGS := $(call ar-option,D)
159# Important: no spaces around options
160ar-option = $(call try-run, $(AR) rc$(1) "$$TMP",$(1),$(2))
161
Andi Kleenccbef162014-02-08 09:01:13 +0100162# ld-version
Andi Kleenccbef162014-02-08 09:01:13 +0100163# Note this is mainly for HJ Lu's 3 number binutil versions
164ld-version = $(shell $(LD) --version | $(srctree)/scripts/ld-version.sh)
165
166# ld-ifversion
167# Usage: $(call ld-ifversion, -ge, 22252, y)
Masahiro Yamada6dcb4e52014-12-25 14:31:27 +0900168ld-ifversion = $(shell [ $(ld-version) $(1) $(2) ] && echo $(3) || echo $(4))
Andi Kleenccbef162014-02-08 09:01:13 +0100169
Oleg Verych5de043f2007-02-06 02:18:21 +0100170######
171
Roman Zippelbeda9f32007-02-08 22:48:51 +0100172###
Sam Ravnborg8ec4b4f2005-07-25 20:10:36 +0000173# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.build obj=
174# Usage:
175# $(Q)$(MAKE) $(build)=dir
Masahiro Yamada5b2389b2014-09-09 20:03:58 +0900176build := -f $(srctree)/scripts/Makefile.build obj
Sam Ravnborg8ec4b4f2005-07-25 20:10:36 +0000177
Michal Marekbc081dd2009-12-07 16:38:33 +0100178###
179# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.modbuiltin obj=
180# Usage:
181# $(Q)$(MAKE) $(modbuiltin)=dir
Masahiro Yamada5b2389b2014-09-09 20:03:58 +0900182modbuiltin := -f $(srctree)/scripts/Makefile.modbuiltin obj
Michal Marekbc081dd2009-12-07 16:38:33 +0100183
Robert Richter9fb5e532014-09-03 15:29:24 +0200184###
185# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.dtbinst obj=
186# Usage:
187# $(Q)$(MAKE) $(dtbinst)=dir
188dtbinst := -f $(if $(KBUILD_SRC),$(srctree)/)scripts/Makefile.dtbinst obj
189
Linus Torvaldsd08372c2014-12-20 13:31:14 -0800190###
Masahiro Yamada371fdc72014-11-26 19:31:13 +0900191# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.clean obj=
192# Usage:
193# $(Q)$(MAKE) $(clean)=dir
194clean := -f $(srctree)/scripts/Makefile.clean obj
195
196###
Masahiro Yamada1846dfb2014-12-02 13:30:46 +0900197# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.headersinst obj=
Masahiro Yamada371fdc72014-11-26 19:31:13 +0900198# Usage:
199# $(Q)$(MAKE) $(hdr-inst)=dir
Masahiro Yamada1846dfb2014-12-02 13:30:46 +0900200hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
Masahiro Yamada371fdc72014-11-26 19:31:13 +0900201
Roman Zippelbeda9f32007-02-08 22:48:51 +0100202# Prefix -I with $(srctree) if it is not an absolute path.
Sam Ravnborg5b91c332008-12-03 21:22:21 +0100203# skip if -I has no parameter
204addtree = $(if $(patsubst -I%,%,$(1)), \
Arnd Bergmanndb547ef2016-06-15 17:45:47 +0200205$(if $(filter-out -I/% -I./% -I../%,$(1)),$(patsubst -I%,-I$(srctree)/%,$(1)),$(1)))
Sam Ravnborgd9df92e2006-04-07 08:36:49 +0200206
Oleg Verych5de043f2007-02-06 02:18:21 +0100207# Find all -I options and call addtree
Roman Zippelbeda9f32007-02-08 22:48:51 +0100208flags = $(foreach o,$($(1)),$(if $(filter -I%,$(o)),$(call addtree,$(o)),$(o)))
Oleg Verych5de043f2007-02-06 02:18:21 +0100209
210# echo command.
211# Short version is used, if $(quiet) equals `quiet_', otherwise full one.
Oleg Verychbff288c2007-02-07 23:04:35 +0100212echo-cmd = $(if $($(quiet)cmd_$(1)),\
Oleg Verych5de043f2007-02-06 02:18:21 +0100213 echo ' $(call escsq,$($(quiet)cmd_$(1)))$(echo-why)';)
214
215# printing commands
Jan Beulich6176aa92006-01-30 10:04:27 +0100216cmd = @$(echo-cmd) $(cmd_$(1))
Sam Ravnborg8ec4b4f2005-07-25 20:10:36 +0000217
Oleg Verych5de043f2007-02-06 02:18:21 +0100218# Add $(obj)/ for paths that are not absolute
Oleg Verychbff288c2007-02-07 23:04:35 +0100219objectify = $(foreach o,$(1),$(if $(filter /%,$(o)),$(o),$(obj)/$(o)))
Sam Ravnborg0a504f22005-09-10 21:02:11 +0200220
Sam Ravnborg8ec4b4f2005-07-25 20:10:36 +0000221###
Oleg Verych5de043f2007-02-06 02:18:21 +0100222# if_changed - execute command if any prerequisite is newer than
Sam Ravnborg8ec4b4f2005-07-25 20:10:36 +0000223# target, or command line has changed
224# if_changed_dep - as if_changed, but uses fixdep to reveal dependencies
225# including used config symbols
226# if_changed_rule - as if_changed but execute rule instead
227# See Documentation/kbuild/makefiles.txt for more info
228
229ifneq ($(KBUILD_NOCMDDEP),1)
Masahiro Yamada9c8fa9b2016-05-07 15:48:26 +0900230# Check if both arguments are the same including their order. Result is empty
231# string if equal. User may override this check using make KBUILD_NOCMDDEP=1
232arg-check = $(filter-out $(subst $(space),$(space_escape),$(strip $(cmd_$@))), \
233 $(subst $(space),$(space_escape),$(strip $(cmd_$1))))
Michal Marekc4d5ee12011-05-16 16:37:34 +0200234else
235arg-check = $(if $(strip $(cmd_$@)),,1)
Sam Ravnborg8ec4b4f2005-07-25 20:10:36 +0000236endif
237
Michal Marek164f0d22014-08-07 21:39:57 +0200238# Replace >$< with >$$< to preserve $ when reloading the .cmd file
239# (needed for make)
240# Replace >#< with >\#< to avoid starting a comment in the .cmd file
241# (needed for make)
242# Replace >'< with >'\''< to be able to enclose the whole string in '...'
243# (needed for the shell)
244make-cmd = $(call escsq,$(subst \#,\\\#,$(subst $$,$$$$,$(cmd_$(1)))))
Jan Beulich6176aa92006-01-30 10:04:27 +0100245
Sam Ravnborg48f1f052006-07-23 19:37:44 +0200246# Find any prerequisites that is newer than target or that does not exist.
247# PHONY targets skipped in both cases.
248any-prereq = $(filter-out $(PHONY),$?) $(filter-out $(PHONY) $(wildcard $^),$^)
249
Oleg Verych5de043f2007-02-06 02:18:21 +0100250# Execute command if command has changed or prerequisite(s) are updated.
Paul Smith4f193362006-03-05 17:14:10 -0500251#
Sam Ravnborg48f1f052006-07-23 19:37:44 +0200252if_changed = $(if $(strip $(any-prereq) $(arg-check)), \
253 @set -e; \
254 $(echo-cmd) $(cmd_$(1)); \
Masahiro Yamada2aedcd02016-03-03 17:36:30 +0900255 printf '%s\n' 'cmd_$@ := $(make-cmd)' > $(dot-target).cmd, @:)
Sam Ravnborg8ec4b4f2005-07-25 20:10:36 +0000256
Oleg Verych5de043f2007-02-06 02:18:21 +0100257# Execute the command and also postprocess generated .d dependencies file.
Sam Ravnborg48f1f052006-07-23 19:37:44 +0200258if_changed_dep = $(if $(strip $(any-prereq) $(arg-check) ), \
259 @set -e; \
Nicolas Pitree4aca452016-02-17 15:50:06 -0500260 $(cmd_and_fixdep), @:)
261
Nicolas Pitrec1a95fd2016-01-22 13:41:57 -0500262ifndef CONFIG_TRIM_UNUSED_KSYMS
263
Nicolas Pitree4aca452016-02-17 15:50:06 -0500264cmd_and_fixdep = \
Sam Ravnborg48f1f052006-07-23 19:37:44 +0200265 $(echo-cmd) $(cmd_$(1)); \
266 scripts/basic/fixdep $(depfile) $@ '$(make-cmd)' > $(dot-target).tmp;\
267 rm -f $(depfile); \
Nicolas Pitree4aca452016-02-17 15:50:06 -0500268 mv -f $(dot-target).tmp $(dot-target).cmd;
Sam Ravnborg8ec4b4f2005-07-25 20:10:36 +0000269
Nicolas Pitrec1a95fd2016-01-22 13:41:57 -0500270else
271
272# Filter out exported kernel symbol names from the preprocessor output.
273# See also __KSYM_DEPS__ in include/linux/export.h.
274# We disable the depfile generation here, so as not to overwrite the existing
275# depfile while fixdep is parsing it.
276flags_nodeps = $(filter-out -Wp$(comma)-M%, $($(1)))
277ksym_dep_filter = \
278 case "$(1)" in \
Nicolas Pitre366f4852016-04-26 11:21:34 -0400279 cc_*_c|cpp_i_c) \
280 $(CPP) $(call flags_nodeps,c_flags) -D__KSYM_DEPS__ $< ;; \
281 as_*_S|cpp_s_S) \
282 $(CPP) $(call flags_nodeps,a_flags) -D__KSYM_DEPS__ $< ;; \
283 boot*|build*|*cpp_lds_S|dtc|host*|vdso*) : ;; \
284 *) echo "Don't know how to preprocess $(1)" >&2; false ;; \
Nicolas Pitref110e0f2016-04-28 17:29:42 -0400285 esac | tr ";" "\n" | sed -rn 's/^.*=== __KSYM_(.*) ===.*$$/KSYM_\1/p'
Nicolas Pitrec1a95fd2016-01-22 13:41:57 -0500286
287cmd_and_fixdep = \
288 $(echo-cmd) $(cmd_$(1)); \
289 $(ksym_dep_filter) | \
290 scripts/basic/fixdep -e $(depfile) $@ '$(make-cmd)' \
291 > $(dot-target).tmp; \
292 rm -f $(depfile); \
293 mv -f $(dot-target).tmp $(dot-target).cmd;
294
295endif
296
Sam Ravnborg8ec4b4f2005-07-25 20:10:36 +0000297# Usage: $(call if_changed_rule,foo)
Roman Zippelbeda9f32007-02-08 22:48:51 +0100298# Will check if $(cmd_foo) or any of the prerequisites changed,
299# and if so will execute $(rule_foo).
Sam Ravnborg48f1f052006-07-23 19:37:44 +0200300if_changed_rule = $(if $(strip $(any-prereq) $(arg-check) ), \
301 @set -e; \
Masahiro Yamada2aedcd02016-03-03 17:36:30 +0900302 $(rule_$(1)), @:)
Sam Ravnborg48f1f052006-07-23 19:37:44 +0200303
Sam Ravnborg45d506b2006-08-08 21:35:14 +0200304###
305# why - tell why a a target got build
306# enabled by make V=2
307# Output (listed in the order they are checked):
308# (1) - due to target is PHONY
309# (2) - due to target missing
310# (3) - due to: file1.h file2.h
311# (4) - due to command line change
312# (5) - due to missing .cmd file
313# (6) - due to target not in $(targets)
314# (1) PHONY targets are always build
315# (2) No target, so we better build it
316# (3) Prerequisite is newer than target
317# (4) The command line stored in the file named dir/.target.cmd
318# differed from actual command line. This happens when compiler
319# options changes
320# (5) No dir/.target.cmd file (used to store command line)
321# (6) No dir/.target.cmd file and target not listed in $(targets)
322# This is a good hint that there is a bug in the kbuild file
323ifeq ($(KBUILD_VERBOSE),2)
324why = \
325 $(if $(filter $@, $(PHONY)),- due to target is PHONY, \
326 $(if $(wildcard $@), \
327 $(if $(strip $(any-prereq)),- due to: $(any-prereq), \
328 $(if $(arg-check), \
329 $(if $(cmd_$@),- due to command line change, \
330 $(if $(filter $@, $(targets)), \
331 - due to missing .cmd file, \
332 - due to $(notdir $@) not in $$(targets) \
333 ) \
334 ) \
335 ) \
336 ), \
337 - due to target missing \
338 ) \
339 )
340
341echo-why = $(call escsq, $(strip $(why)))
342endif
David Woodhouse3ee550f2015-08-14 16:17:16 +0100343
344###############################################################################
345#
346# When a Kconfig string contains a filename, it is suitable for
347# passing to shell commands. It is surrounded by double-quotes, and
348# any double-quotes or backslashes within it are escaped by
349# backslashes.
350#
351# This is no use for dependencies or $(wildcard). We need to strip the
352# surrounding quotes and the escaping from quotes and backslashes, and
353# we *do* need to escape any spaces in the string. So, for example:
354#
355# Usage: $(eval $(call config_filename,FOO))
356#
357# Defines FOO_FILENAME based on the contents of the CONFIG_FOO option,
358# transformed as described above to be suitable for use within the
359# makefile.
360#
361# Also, if the filename is a relative filename and exists in the source
362# tree but not the build tree, define FOO_SRCPREFIX as $(srctree)/ to
363# be prefixed to *both* command invocation and dependencies.
364#
365# Note: We also print the filenames in the quiet_cmd_foo text, and
366# perhaps ought to have a version specially escaped for that purpose.
367# But it's only cosmetic, and $(patsubst "%",%,$(CONFIG_FOO)) is good
368# enough. It'll strip the quotes in the common case where there's no
369# space and it's a simple filename, and it'll retain the quotes when
370# there's a space. There are some esoteric cases in which it'll print
371# the wrong thing, but we don't really care. The actual dependencies
372# and commands *do* get it right, with various combinations of single
373# and double quotes, backslashes and spaces in the filenames.
374#
375###############################################################################
376#
David Woodhouse3ee550f2015-08-14 16:17:16 +0100377define config_filename
378ifneq ($$(CONFIG_$(1)),"")
379$(1)_FILENAME := $$(subst \\,\,$$(subst \$$(quote),$$(quote),$$(subst $$(space_escape),\$$(space),$$(patsubst "%",%,$$(subst $$(space),$$(space_escape),$$(CONFIG_$(1)))))))
380ifneq ($$(patsubst /%,%,$$(firstword $$($(1)_FILENAME))),$$(firstword $$($(1)_FILENAME)))
381else
382ifeq ($$(wildcard $$($(1)_FILENAME)),)
383ifneq ($$(wildcard $$(srctree)/$$($(1)_FILENAME)),)
384$(1)_SRCPREFIX := $(srctree)/
385endif
386endif
387endif
388endif
389endef
390#
391###############################################################################