# SPDX-License-Identifier: GPL-2.0# ==========================================================================# Installing headers## All headers under include/uapi, include/generated/uapi,# arch/<arch>/include/uapi and arch/<arch>/include/generated/uapi are# exported.# They are preprocessed to remove __KERNEL__ section of the file.## ========================================================================== PHONY := __headers__headers: include $(srctree)/scripts/Kbuild.include src := $(srctree)/$(obj)gen := $(objtree)/$(subst include/,include/generated/,$(obj))dst := usr/include -include $(src)/Kbuild # $(filter %/, ...) is a workaround for GNU Make <= 4.2.1, where# $(wildcard $(src)/*/) contains not only directories but also regular files.src-subdirs := $(patsubst $(src)/%/,%,$(filter %/, $(wildcard $(src)/*/)))gen-subdirs := $(patsubst $(gen)/%/,%,$(filter %/, $(wildcard $(gen)/*/)))all-subdirs := $(sort $(src-subdirs) $(gen-subdirs)) src-headers := $(if $(src-subdirs), $(shell cd $(src) && find $(src-subdirs) -name '*.h'))src-headers := $(filter-out $(no-export-headers), $(src-headers))gen-headers := $(if $(gen-subdirs), $(shell cd $(gen) && find $(gen-subdirs) -name '*.h'))gen-headers := $(filter-out $(no-export-headers), $(gen-headers)) # If the same header is exported from source and generated directories,# the former takes precedence, but this should be warned.duplicated := $(filter $(gen-headers), $(src-headers))$(if $(duplicated), $(warning duplicated header export: $(duplicated))) gen-headers := $(filter-out $(duplicated), $(gen-headers)) # Add dst path prefixall-subdirs := $(addprefix $(dst)/, $(all-subdirs))src-headers := $(addprefix $(dst)/, $(src-headers))gen-headers := $(addprefix $(dst)/, $(gen-headers))all-headers := $(src-headers) $(gen-headers) # Work out what needs to be removedold-subdirs := $(wildcard $(all-subdirs))old-headers := $(if $(old-subdirs),$(shell find $(old-subdirs) -name '*.h'))unwanted    := $(filter-out $(all-headers), $(old-headers)) # Create directoriesexisting-dirs := $(sort $(dir $(old-headers)))wanted-dirs   := $(sort $(dir $(all-headers)))new-dirs      := $(filter-out $(existing-dirs), $(wanted-dirs))$(if $(new-dirs), $(shell mkdir -p $(new-dirs))) # Rulesquiet_cmd_install = HDRINST $@      cmd_install = $(CONFIG_SHELL) $(srctree)/scripts/headers_install.sh $< $@ $(src-headers): $(dst)/%.h: $(src)/%.h $(srctree)/scripts/headers_install.sh FORCE	$(call if_changed,install) $(gen-headers): $(dst)/%.h: $(gen)/%.h $(srctree)/scripts/headers_install.sh FORCE	$(call if_changed,install) quiet_cmd_remove = REMOVE  $(unwanted)      cmd_remove = rm -f $(unwanted) __headers: $(all-headers)ifneq ($(unwanted),)	$(call cmd,remove)endif	@: existing-headers := $(filter $(old-headers), $(all-headers)) -include $(foreach f,$(existing-headers),$(dir $(f)).$(notdir $(f)).cmd) PHONY += FORCEFORCE: .PHONY: $(PHONY)