# SPDX-License-Identifier: GPL-2.0

####

# kbuild: Generic definitions

# Convenient variables

comma := ,

quote := "

squote := '

empty :=

space := $(empty) $(empty)

space_escape := _-_SPACE_-_

pound := \#

define newline

endef

###

# Comparison macros.

# Usage: $(call test-lt, $(CONFIG_LLD_VERSION), 150000)

#

# Use $(intcmp ...) if supported. (Make >= 4.4)

# Otherwise, fall back to the 'test' shell command.

ifeq ($(intcmp 1,0,,,y),y)

test-ge = $(intcmp $(strip $1)0, $(strip $2)0,,y,y)

test-gt = $(intcmp $(strip $1)0, $(strip $2)0,,,y)

else

test-ge = $(shell test $(strip $1)0 -ge $(strip $2)0 && echo y)

test-gt = $(shell test $(strip $1)0 -gt $(strip $2)0 && echo y)

endif

test-le = $(call test-ge, $2, $1)

test-lt = $(call test-gt, $2, $1)

###

# Name of target with a '.' as filename prefix. foo/bar.o => foo/.bar.o

dot-target = $(dir $@).$(notdir $@)

###

# Name of target with a '.tmp_' as filename prefix. foo/bar.o => foo/.tmp_bar.o

tmp-target = $(dir $@).tmp_$(notdir $@)

###

# The temporary file to save gcc -MMD generated dependencies must not

# contain a comma

depfile = $(subst $(comma),_,$(dot-target).d)

###

# filename of target with directory and extension stripped

basetarget = $(basename $(notdir $@))

###

# real prerequisites without phony targets

real-prereqs = $(filter-out $(PHONY), $^)

###

# Escape single quote for use in echo statements

escsq = $(subst $(squote),'\$(squote)',$1)

###

# Quote a string to pass it to C files. foo => '"foo"'

stringify = $(squote)$(quote)$1$(quote)$(squote)

###

# The path to Kbuild or Makefile. Kbuild has precedence over Makefile.

kbuild-file = $(or $(wildcard $(src)/Kbuild),$(src)/Makefile)

###

# Read a file, replacing newlines with spaces

#

# Make 4.2 or later can read a file by using its builtin function.

ifneq ($(filter-out 4.0 4.1, $(MAKE_VERSION)),)

read-file = $(subst $(newline),$(space),$(file < $1))

else

read-file = $(shell cat $1 2>/dev/null)

endif

###

# Easy method for doing a status message

kecho := :

quiet_kecho := echo

silent_kecho := :

kecho := $($(quiet)kecho)

###

# filechk is used to check if the content of a generated file is updated.

# Sample usage:

#

# filechk_sample = echo $(KERNELRELEASE)

# version.h: FORCE

# $(call filechk,sample)

#

# The rule defined shall write to stdout the content of the new file.

# The existing file will be compared with the new one.

# - If no file exist it is created

# - If the content differ the new file is used

# - If they are equal no change, and no timestamp update

define filechk

$(check-FORCE)

$(Q)set -e; \

mkdir -p $(dir $@); \

trap "rm -f $(tmp-target)" EXIT; \

{ $(filechk_$(1)); } > $(tmp-target); \

if [ ! -r $@ ] || ! cmp -s $@ $(tmp-target); then \

$(kecho) ' UPD $@'; \

mv -f $(tmp-target) $@; \

fi

endef

###

# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.build obj=

# Usage:

# $(Q)$(MAKE) $(build)=dir

build := -f $(srctree)/scripts/Makefile.build obj

###

# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.clean obj=

# Usage:

# $(Q)$(MAKE) $(clean)=dir

clean := -f $(srctree)/scripts/Makefile.clean obj

# pring log

#

# If quiet is "silent_", print nothing and sink stdout

# If quiet is "quiet_", print short log

# If quiet is empty, print short log and whole command

silent_log_print = exec >/dev/null;

quiet_log_print = $(if $(quiet_cmd_$1), echo ' $(call escsq,$(quiet_cmd_$1)$(why))';)

log_print = echo '$(pound) $(call escsq,$(or $(quiet_cmd_$1),cmd_$1 $@)$(why))'; \

echo ' $(call escsq,$(cmd_$1))';

# Delete the target on interruption

#

# GNU Make automatically deletes the target if it has already been changed by

# the interrupted recipe. So, you can safely stop the build by Ctrl-C (Make

# will delete incomplete targets), and resume it later.

#

# However, this does not work when the stderr is piped to another program, like

# $ make >&2 | tee log

# Make dies with SIGPIPE before cleaning the targets.

#

# To address it, we clean the target in signal traps.

#

# Make deletes the target when it catches SIGHUP, SIGINT, SIGQUIT, SIGTERM.

# So, we cover them, and also SIGPIPE just in case.

#

# Of course, this is unneeded for phony targets.

delete-on-interrupt = \

$(if $(filter-out $(PHONY), $@), \

$(foreach sig, HUP INT QUIT TERM PIPE, \

trap 'rm -f $@; trap - $(sig); kill -s $(sig) $$$$' $(sig);))

# print and execute commands

cmd = @$(if $(cmd_$(1)),set -e; $($(quiet)log_print) $(delete-on-interrupt) $(cmd_$(1)),:)

###

# if_changed - execute command if any prerequisite is newer than

# target, or command line has changed

# if_changed_dep - as if_changed, but uses fixdep to reveal dependencies

# including used config symbols

# if_changed_rule - as if_changed but execute rule instead

# See Documentation/kbuild/makefiles.rst for more info

ifneq ($(KBUILD_NOCMDDEP),1)

# Check if both commands are the same including their order. Result is empty

# string if equal. User may override this check using make KBUILD_NOCMDDEP=1

# If the target does not exist, the *.cmd file should not be included so

# $(savedcmd_$@) gets empty. Then, target will be built even if $(newer-prereqs)

# happens to become empty.

cmd-check = $(filter-out $(subst $(space),$(space_escape),$(strip $(savedcmd_$@))), \

$(subst $(space),$(space_escape),$(strip $(cmd_$1))))

else

# We still need to detect missing targets.

cmd-check = $(if $(strip $(savedcmd_$@)),,1)

endif

# Replace >$< with >$$< to preserve $ when reloading the .cmd file

# (needed for make)

# Replace >#< with >$(pound)< to avoid starting a comment in the .cmd file

# (needed for make)

# Replace >'< with >'\''< to be able to enclose the whole string in '...'

# (needed for the shell)

make-cmd = $(call escsq,$(subst $(pound),$$(pound),$(subst $$,$$$$,$(cmd_$(1)))))

# Find any prerequisites that are newer than target or that do not exist.

# PHONY targets skipped in both cases.

# If there is no prerequisite other than phony targets, $(newer-prereqs) becomes

# empty even if the target does not exist. cmd-check saves this corner case.

newer-prereqs = $(filter-out $(PHONY),$?)

# It is a typical mistake to forget the FORCE prerequisite. Check it here so

# no more breakage will slip in.

check-FORCE = $(if $(filter FORCE, $^),,$(warning FORCE prerequisite is missing))

if-changed-cond = $(newer-prereqs)$(cmd-check)$(check-FORCE)

# Execute command if command has changed or prerequisite(s) are updated.

if_changed = $(if $(if-changed-cond),$(cmd_and_savecmd),@:)

cmd_and_savecmd = \

$(cmd); \

printf '%s\n' 'savedcmd_$@ := $(make-cmd)' > $(dot-target).cmd

# Execute the command and also postprocess generated .d dependencies file.

if_changed_dep = $(if $(if-changed-cond),$(cmd_and_fixdep),@:)

cmd_and_fixdep = \

$(cmd); \

scripts/basic/fixdep $(depfile) $@ '$(make-cmd)' > $(dot-target).cmd;\

rm -f $(depfile)

# Usage: $(call if_changed_rule,foo)

# Will check if $(cmd_foo) or any of the prerequisites changed,

# and if so will execute $(rule_foo).

if_changed_rule = $(if $(if-changed-cond),$(rule_$(1)),@:)

###

# why - tell why a target got built

# enabled by make V=2

# Output (listed in the order they are checked):

# (1) - due to target is PHONY

# (2) - due to target missing

# (3) - due to: file1.h file2.h

# (4) - due to command line change

# (5) - due to missing .cmd file

# (6) - due to target not in $(targets)

# (1) PHONY targets are always build

# (2) No target, so we better build it

# (3) Prerequisite is newer than target

# (4) The command line stored in the file named dir/.target.cmd

# differed from actual command line. This happens when compiler

# options changes

# (5) No dir/.target.cmd file (used to store command line)

# (6) No dir/.target.cmd file and target not listed in $(targets)

# This is a good hint that there is a bug in the kbuild file

ifneq ($(findstring 2, $(KBUILD_VERBOSE)),)

_why = \

$(if $(filter $@, $(PHONY)),- due to target is PHONY, \

$(if $(wildcard $@), \

$(if $(newer-prereqs),- due to: $(newer-prereqs), \

$(if $(cmd-check), \

$(if $(savedcmd_$@),- due to command line change, \

$(if $(filter $@, $(targets)), \

- due to missing .cmd file, \

- due to $(notdir $@) not in $$(targets) \

) \

) \

) \

), \

- due to target missing \

) \

)

why = $(space)$(strip $(_why))

endif

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

# delete partially updated (i.e. corrupted) files on error

.DELETE_ON_ERROR:

# do not delete intermediate files automatically

#

# .NOTINTERMEDIATE is more correct, but only available on newer Make versions.

# Make 4.4 introduced .NOTINTERMEDIATE, and it appears in .FEATURES, but the

# global .NOTINTERMEDIATE does not work. We can use it on Make > 4.4.

# Use .SECONDARY for older Make versions, but "newer-prereq" cannot detect

# deleted files.

ifneq ($(and $(filter notintermediate, $(.FEATURES)),$(filter-out 4.4,$(MAKE_VERSION))),)

.NOTINTERMEDIATE:

else

.SECONDARY:

endif