tools/lib/bpf/Makefile - linux/kernel/git/gregkh/usb - Git at Google

 # SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
 # Most of this file is copied from tools/lib/traceevent/Makefile

 LIBBPF_VERSION := $(shell \
 	grep -oE '^LIBBPF_([0-9.]+)' libbpf.map | \
 	sort -rV | head -n1 | cut -d'_' -f2)
 LIBBPF_MAJOR_VERSION := $(firstword $(subst ., ,$(LIBBPF_VERSION)))

 MAKEFLAGS += --no-print-directory

 # This will work when bpf is built in tools env. where srctree
 # isn't set and when invoked from selftests build, where srctree
 # is a ".". building_out_of_srctree is undefined for in srctree
 # builds
 ifndef building_out_of_srctree
 srctree := $(patsubst %/,%,$(dir $(CURDIR)))
 srctree := $(patsubst %/,%,$(dir $(srctree)))
 srctree := $(patsubst %/,%,$(dir $(srctree)))
 #$(info Determined 'srctree' to be $(srctree))
 endif

 INSTALL = install

 # Use DESTDIR for installing into a different root directory.
 # This is useful for building a package. The program will be
 # installed in this directory as if it was the root directory.
 # Then the build tool can move it later.
 DESTDIR ?=
 DESTDIR_SQ = '$(subst ','\'',$(DESTDIR))'

 include $(srctree)/tools/scripts/Makefile.arch

 ifeq ($(LP64), 1)
   libdir_relative = lib64
 else
   libdir_relative = lib
 endif

 prefix ?= /usr/local
 libdir = $(prefix)/$(libdir_relative)
 man_dir = $(prefix)/share/man
 man_dir_SQ = '$(subst ','\'',$(man_dir))'

 export man_dir man_dir_SQ INSTALL
 export DESTDIR DESTDIR_SQ

 include $(srctree)/tools/scripts/Makefile.include

 # copy a bit from Linux kbuild

 ifeq ("$(origin V)", "command line")
   VERBOSE = $(V)
 endif
 ifndef VERBOSE
   VERBOSE = 0
 endif

 FEATURE_USER = .libbpf
 FEATURE_TESTS = libelf libelf-mmap zlib bpf reallocarray
 FEATURE_DISPLAY = libelf zlib bpf

 INCLUDES = -I. -I$(srctree)/tools/include -I$(srctree)/tools/arch/$(ARCH)/include/uapi -I$(srctree)/tools/include/uapi
 FEATURE_CHECK_CFLAGS-bpf = $(INCLUDES)

 check_feat := 1
 NON_CHECK_FEAT_TARGETS := clean TAGS tags cscope help
 ifdef MAKECMDGOALS
 ifeq ($(filter-out $(NON_CHECK_FEAT_TARGETS),$(MAKECMDGOALS)),)
   check_feat := 0
 endif
 endif

 ifeq ($(check_feat),1)
 ifeq ($(FEATURES_DUMP),)
 include $(srctree)/tools/build/Makefile.feature
 else
 include $(FEATURES_DUMP)
 endif
 endif

 export prefix libdir src obj

 # Shell quotes
 libdir_SQ = $(subst ','\'',$(libdir))
 libdir_relative_SQ = $(subst ','\'',$(libdir_relative))

 OBJ		= $@
 N		=

 LIB_TARGET	= libbpf.a libbpf.so.$(LIBBPF_VERSION)
 LIB_FILE	= libbpf.a libbpf.so*
 PC_FILE		= libbpf.pc

 # Set compile option CFLAGS
 ifdef EXTRA_CFLAGS
   CFLAGS := $(EXTRA_CFLAGS)
 else
   CFLAGS := -g -Wall
 endif

 ifeq ($(feature-libelf-mmap), 1)
   override CFLAGS += -DHAVE_LIBELF_MMAP_SUPPORT
 endif

 ifeq ($(feature-reallocarray), 0)
   override CFLAGS += -DCOMPAT_NEED_REALLOCARRAY
 endif

 # Append required CFLAGS
 override CFLAGS += $(EXTRA_WARNINGS)
 override CFLAGS += -Werror -Wall
 override CFLAGS += -fPIC
 override CFLAGS += $(INCLUDES)
 override CFLAGS += -fvisibility=hidden
 override CFLAGS += -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64

 # flags specific for shared library
 SHLIB_FLAGS := -DSHARED

 ifeq ($(VERBOSE),1)
   Q =
 else
   Q = @
 endif

 # Disable command line variables (CFLAGS) override from top
 # level Makefile (perf), otherwise build Makefile will get
 # the same command line setup.
 MAKEOVERRIDES=

 all:

 export srctree OUTPUT CC LD CFLAGS V
 include $(srctree)/tools/build/Makefile.include

 SHARED_OBJDIR	:= $(OUTPUT)sharedobjs/
 STATIC_OBJDIR	:= $(OUTPUT)staticobjs/
 BPF_IN_SHARED	:= $(SHARED_OBJDIR)libbpf-in.o
 BPF_IN_STATIC	:= $(STATIC_OBJDIR)libbpf-in.o
 VERSION_SCRIPT	:= libbpf.map
 BPF_HELPER_DEFS	:= $(OUTPUT)bpf_helper_defs.h

 LIB_TARGET	:= $(addprefix $(OUTPUT),$(LIB_TARGET))
 LIB_FILE	:= $(addprefix $(OUTPUT),$(LIB_FILE))
 PC_FILE		:= $(addprefix $(OUTPUT),$(PC_FILE))

 TAGS_PROG := $(if $(shell which etags 2>/dev/null),etags,ctags)

 GLOBAL_SYM_COUNT = $(shell readelf -s --wide $(BPF_IN_SHARED) | \
 			   cut -d "@" -f1 | sed 's/_v[0-9]_[0-9]_[0-9].*//' | \
 			   sed 's/\[.*\]//' | \
 			   awk '/GLOBAL/ && /DEFAULT/ && !/UND/ {print $$NF}' | \
 			   sort -u | wc -l)
 VERSIONED_SYM_COUNT = $(shell readelf -s --wide $(OUTPUT)libbpf.so | \
 			      grep -Eo '[^ ]+@LIBBPF_' | cut -d@ -f1 | sort -u | wc -l)

 CMD_TARGETS = $(LIB_TARGET) $(PC_FILE)

 all: fixdep
 	$(Q)$(MAKE) all_cmd

 all_cmd: $(CMD_TARGETS) check

 $(BPF_IN_SHARED): force elfdep zdep bpfdep $(BPF_HELPER_DEFS)
 	@(test -f ../../include/uapi/linux/bpf.h -a -f ../../../include/uapi/linux/bpf.h && ( \
 	(diff -B ../../include/uapi/linux/bpf.h ../../../include/uapi/linux/bpf.h >/dev/null) || \
 	echo "Warning: Kernel ABI header at 'tools/include/uapi/linux/bpf.h' differs from latest version at 'include/uapi/linux/bpf.h'" >&2 )) || true
 	@(test -f ../../include/uapi/linux/bpf_common.h -a -f ../../../include/uapi/linux/bpf_common.h && ( \
 	(diff -B ../../include/uapi/linux/bpf_common.h ../../../include/uapi/linux/bpf_common.h >/dev/null) || \
 	echo "Warning: Kernel ABI header at 'tools/include/uapi/linux/bpf_common.h' differs from latest version at 'include/uapi/linux/bpf_common.h'" >&2 )) || true
 	@(test -f ../../include/uapi/linux/netlink.h -a -f ../../../include/uapi/linux/netlink.h && ( \
 	(diff -B ../../include/uapi/linux/netlink.h ../../../include/uapi/linux/netlink.h >/dev/null) || \
 	echo "Warning: Kernel ABI header at 'tools/include/uapi/linux/netlink.h' differs from latest version at 'include/uapi/linux/netlink.h'" >&2 )) || true
 	@(test -f ../../include/uapi/linux/if_link.h -a -f ../../../include/uapi/linux/if_link.h && ( \
 	(diff -B ../../include/uapi/linux/if_link.h ../../../include/uapi/linux/if_link.h >/dev/null) || \
 	echo "Warning: Kernel ABI header at 'tools/include/uapi/linux/if_link.h' differs from latest version at 'include/uapi/linux/if_link.h'" >&2 )) || true
 	@(test -f ../../include/uapi/linux/if_xdp.h -a -f ../../../include/uapi/linux/if_xdp.h && ( \
 	(diff -B ../../include/uapi/linux/if_xdp.h ../../../include/uapi/linux/if_xdp.h >/dev/null) || \
 	echo "Warning: Kernel ABI header at 'tools/include/uapi/linux/if_xdp.h' differs from latest version at 'include/uapi/linux/if_xdp.h'" >&2 )) || true
 	$(Q)$(MAKE) $(build)=libbpf OUTPUT=$(SHARED_OBJDIR) CFLAGS="$(CFLAGS) $(SHLIB_FLAGS)"

 $(BPF_IN_STATIC): force elfdep zdep bpfdep $(BPF_HELPER_DEFS)
 	$(Q)$(MAKE) $(build)=libbpf OUTPUT=$(STATIC_OBJDIR)

 $(BPF_HELPER_DEFS): $(srctree)/tools/include/uapi/linux/bpf.h
 	$(QUIET_GEN)$(srctree)/scripts/bpf_helpers_doc.py --header \
 		--file $(srctree)/tools/include/uapi/linux/bpf.h > $(BPF_HELPER_DEFS)

 $(OUTPUT)libbpf.so: $(OUTPUT)libbpf.so.$(LIBBPF_VERSION)

 $(OUTPUT)libbpf.so.$(LIBBPF_VERSION): $(BPF_IN_SHARED)
 	$(QUIET_LINK)$(CC) $(LDFLAGS) \
 		--shared -Wl,-soname,libbpf.so.$(LIBBPF_MAJOR_VERSION) \
 		-Wl,--version-script=$(VERSION_SCRIPT) $^ -lelf -lz -o $@
 	@ln -sf $(@F) $(OUTPUT)libbpf.so
 	@ln -sf $(@F) $(OUTPUT)libbpf.so.$(LIBBPF_MAJOR_VERSION)

 $(OUTPUT)libbpf.a: $(BPF_IN_STATIC)
 	$(QUIET_LINK)$(RM) $@; $(AR) rcs $@ $^

 $(OUTPUT)libbpf.pc:
 	$(QUIET_GEN)sed -e "s|@PREFIX@|$(prefix)|" \
 		-e "s|@LIBDIR@|$(libdir_SQ)|" \
 		-e "s|@VERSION@|$(LIBBPF_VERSION)|" \
 		< libbpf.pc.template > $@

 check: check_abi

 check_abi: $(OUTPUT)libbpf.so
 	@if [ "$(GLOBAL_SYM_COUNT)" != "$(VERSIONED_SYM_COUNT)" ]; then	 \
 		echo "Warning: Num of global symbols in $(BPF_IN_SHARED)"	 \
 		     "($(GLOBAL_SYM_COUNT)) does NOT match with num of"	 \
 		     "versioned symbols in $^ ($(VERSIONED_SYM_COUNT))." \
 		     "Please make sure all LIBBPF_API symbols are"	 \
 		     "versioned in $(VERSION_SCRIPT)." >&2;		 \
 		readelf -s --wide $(BPF_IN_SHARED) |			 \
 		    cut -d "@" -f1 | sed 's/_v[0-9]_[0-9]_[0-9].*//' |	 \
 		    sed 's/\[.*\]//' |					 \
 		    awk '/GLOBAL/ && /DEFAULT/ && !/UND/ {print $$NF}'|  \
 		    sort -u > $(OUTPUT)libbpf_global_syms.tmp;		 \
 		readelf -s --wide $(OUTPUT)libbpf.so |			 \
 		    grep -Eo '[^ ]+@LIBBPF_' | cut -d@ -f1 |		 \
 		    sort -u > $(OUTPUT)libbpf_versioned_syms.tmp; 	 \
 		diff -u $(OUTPUT)libbpf_global_syms.tmp			 \
 		     $(OUTPUT)libbpf_versioned_syms.tmp;		 \
 		rm $(OUTPUT)libbpf_global_syms.tmp			 \
 		   $(OUTPUT)libbpf_versioned_syms.tmp;			 \
 		exit 1;							 \
 	fi

 define do_install_mkdir
 	if [ ! -d '$(DESTDIR_SQ)$1' ]; then		\
 		$(INSTALL) -d -m 755 '$(DESTDIR_SQ)$1';	\
 	fi
 endef

 define do_install
 	if [ ! -d '$(DESTDIR_SQ)$2' ]; then		\
 		$(INSTALL) -d -m 755 '$(DESTDIR_SQ)$2';	\
 	fi;						\
 	$(INSTALL) $1 $(if $3,-m $3,) '$(DESTDIR_SQ)$2'
 endef

 install_lib: all_cmd
 	$(call QUIET_INSTALL, $(LIB_TARGET)) \
 		$(call do_install_mkdir,$(libdir_SQ)); \
 		cp -fpR $(LIB_FILE) $(DESTDIR)$(libdir_SQ)

 install_headers: $(BPF_HELPER_DEFS)
 	$(call QUIET_INSTALL, headers) \
 		$(call do_install,bpf.h,$(prefix)/include/bpf,644); \
 		$(call do_install,libbpf.h,$(prefix)/include/bpf,644); \
 		$(call do_install,btf.h,$(prefix)/include/bpf,644); \
 		$(call do_install,libbpf_util.h,$(prefix)/include/bpf,644); \
 		$(call do_install,libbpf_common.h,$(prefix)/include/bpf,644); \
 		$(call do_install,xsk.h,$(prefix)/include/bpf,644); \
 		$(call do_install,bpf_helpers.h,$(prefix)/include/bpf,644); \
 		$(call do_install,$(BPF_HELPER_DEFS),$(prefix)/include/bpf,644); \
 		$(call do_install,bpf_tracing.h,$(prefix)/include/bpf,644); \
 		$(call do_install,bpf_endian.h,$(prefix)/include/bpf,644); \
 		$(call do_install,bpf_core_read.h,$(prefix)/include/bpf,644);

 install_pkgconfig: $(PC_FILE)
 	$(call QUIET_INSTALL, $(PC_FILE)) \
 		$(call do_install,$(PC_FILE),$(libdir_SQ)/pkgconfig,644)

 install: install_lib install_pkgconfig

 ### Cleaning rules

 config-clean:
 	$(call QUIET_CLEAN, config)
 	$(Q)$(MAKE) -C $(srctree)/tools/build/feature/ clean >/dev/null

 clean:
 	$(call QUIET_CLEAN, libbpf) $(RM) -rf $(CMD_TARGETS)		     \
 		*~ .*.d .*.cmd LIBBPF-CFLAGS $(BPF_HELPER_DEFS)		     \
 		$(SHARED_OBJDIR) $(STATIC_OBJDIR)			     \
 		$(addprefix $(OUTPUT),					     \
 			    *.o *.a *.so *.so.$(LIBBPF_MAJOR_VERSION) *.pc)
 	$(call QUIET_CLEAN, core-gen) $(RM) $(OUTPUT)FEATURE-DUMP.libbpf


 PHONY += force elfdep zdep bpfdep cscope tags
 force:

 elfdep:
 	@if [ "$(feature-libelf)" != "1" ]; then echo "No libelf found"; exit 1 ; fi

 zdep:
 	@if [ "$(feature-zlib)" != "1" ]; then echo "No zlib found"; exit 1 ; fi

 bpfdep:
 	@if [ "$(feature-bpf)" != "1" ]; then echo "BPF API too old"; exit 1 ; fi

 cscope:
 	ls *.c *.h > cscope.files
 	cscope -b -q -I $(srctree)/include -f cscope.out

 tags:
 	rm -f TAGS tags
 	ls *.c *.h | xargs $(TAGS_PROG) -a

 # Declare the contents of the .PHONY variable as phony.  We keep that
 # information in a variable so we can use it in if_changed and friends.
 .PHONY: $(PHONY)

 # Delete partially updated (corrupted) files on error
 .DELETE_ON_ERROR:
	# SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
	# Most of this file is copied from tools/lib/traceevent/Makefile

	LIBBPF_VERSION := $(shell \
	grep -oE '^LIBBPF_([0-9.]+)' libbpf.map \| \
	sort -rV \| head -n1 \| cut -d'_' -f2)
	LIBBPF_MAJOR_VERSION := $(firstword $(subst ., ,$(LIBBPF_VERSION)))

	MAKEFLAGS += --no-print-directory

	# This will work when bpf is built in tools env. where srctree
	# isn't set and when invoked from selftests build, where srctree
	# is a ".". building_out_of_srctree is undefined for in srctree
	# builds
	ifndef building_out_of_srctree
	srctree := $(patsubst %/,%,$(dir $(CURDIR)))
	srctree := $(patsubst %/,%,$(dir $(srctree)))
	srctree := $(patsubst %/,%,$(dir $(srctree)))
	#$(info Determined 'srctree' to be $(srctree))
	endif

	INSTALL = install

	# Use DESTDIR for installing into a different root directory.
	# This is useful for building a package. The program will be
	# installed in this directory as if it was the root directory.
	# Then the build tool can move it later.
	DESTDIR ?=
	DESTDIR_SQ = '$(subst ','\'',$(DESTDIR))'

	include $(srctree)/tools/scripts/Makefile.arch

	ifeq ($(LP64), 1)
	libdir_relative = lib64
	else
	libdir_relative = lib
	endif

	prefix ?= /usr/local
	libdir = $(prefix)/$(libdir_relative)
	man_dir = $(prefix)/share/man
	man_dir_SQ = '$(subst ','\'',$(man_dir))'

	export man_dir man_dir_SQ INSTALL
	export DESTDIR DESTDIR_SQ

	include $(srctree)/tools/scripts/Makefile.include

	# copy a bit from Linux kbuild

	ifeq ("$(origin V)", "command line")
	VERBOSE = $(V)
	endif
	ifndef VERBOSE
	VERBOSE = 0
	endif

	FEATURE_USER = .libbpf
	FEATURE_TESTS = libelf libelf-mmap zlib bpf reallocarray
	FEATURE_DISPLAY = libelf zlib bpf

	INCLUDES = -I. -I$(srctree)/tools/include -I$(srctree)/tools/arch/$(ARCH)/include/uapi -I$(srctree)/tools/include/uapi
	FEATURE_CHECK_CFLAGS-bpf = $(INCLUDES)

	check_feat := 1
	NON_CHECK_FEAT_TARGETS := clean TAGS tags cscope help
	ifdef MAKECMDGOALS
	ifeq ($(filter-out $(NON_CHECK_FEAT_TARGETS),$(MAKECMDGOALS)),)
	check_feat := 0
	endif
	endif

	ifeq ($(check_feat),1)
	ifeq ($(FEATURES_DUMP),)
	include $(srctree)/tools/build/Makefile.feature
	else
	include $(FEATURES_DUMP)
	endif
	endif

	export prefix libdir src obj

	# Shell quotes
	libdir_SQ = $(subst ','\'',$(libdir))
	libdir_relative_SQ = $(subst ','\'',$(libdir_relative))

	OBJ = $@
	N =

	LIB_TARGET = libbpf.a libbpf.so.$(LIBBPF_VERSION)
	LIB_FILE = libbpf.a libbpf.so*
	PC_FILE = libbpf.pc

	# Set compile option CFLAGS
	ifdef EXTRA_CFLAGS
	CFLAGS := $(EXTRA_CFLAGS)
	else
	CFLAGS := -g -Wall
	endif

	ifeq ($(feature-libelf-mmap), 1)
	override CFLAGS += -DHAVE_LIBELF_MMAP_SUPPORT
	endif

	ifeq ($(feature-reallocarray), 0)
	override CFLAGS += -DCOMPAT_NEED_REALLOCARRAY
	endif

	# Append required CFLAGS
	override CFLAGS += $(EXTRA_WARNINGS)
	override CFLAGS += -Werror -Wall
	override CFLAGS += -fPIC
	override CFLAGS += $(INCLUDES)
	override CFLAGS += -fvisibility=hidden
	override CFLAGS += -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64

	# flags specific for shared library
	SHLIB_FLAGS := -DSHARED

	ifeq ($(VERBOSE),1)
	Q =
	else
	Q = @
	endif

	# Disable command line variables (CFLAGS) override from top
	# level Makefile (perf), otherwise build Makefile will get
	# the same command line setup.
	MAKEOVERRIDES=

	all:

	export srctree OUTPUT CC LD CFLAGS V
	include $(srctree)/tools/build/Makefile.include

	SHARED_OBJDIR := $(OUTPUT)sharedobjs/
	STATIC_OBJDIR := $(OUTPUT)staticobjs/
	BPF_IN_SHARED := $(SHARED_OBJDIR)libbpf-in.o
	BPF_IN_STATIC := $(STATIC_OBJDIR)libbpf-in.o
	VERSION_SCRIPT := libbpf.map
	BPF_HELPER_DEFS := $(OUTPUT)bpf_helper_defs.h

	LIB_TARGET := $(addprefix $(OUTPUT),$(LIB_TARGET))
	LIB_FILE := $(addprefix $(OUTPUT),$(LIB_FILE))
	PC_FILE := $(addprefix $(OUTPUT),$(PC_FILE))

	TAGS_PROG := $(if $(shell which etags 2>/dev/null),etags,ctags)

	GLOBAL_SYM_COUNT = $(shell readelf -s --wide $(BPF_IN_SHARED) \| \
	cut -d "@" -f1 \| sed 's/_v[0-9]_[0-9]_[0-9].*//' \| \
	sed 's/\[.*\]//' \| \
	awk '/GLOBAL/ && /DEFAULT/ && !/UND/ {print $$NF}' \| \
	sort -u \| wc -l)
	VERSIONED_SYM_COUNT = $(shell readelf -s --wide $(OUTPUT)libbpf.so \| \
	grep -Eo '[^ ]+@LIBBPF_' \| cut -d@ -f1 \| sort -u \| wc -l)

	CMD_TARGETS = $(LIB_TARGET) $(PC_FILE)

	all: fixdep
	$(Q)$(MAKE) all_cmd

	all_cmd: $(CMD_TARGETS) check

	$(BPF_IN_SHARED): force elfdep zdep bpfdep $(BPF_HELPER_DEFS)
	@(test -f ../../include/uapi/linux/bpf.h -a -f ../../../include/uapi/linux/bpf.h && ( \
	(diff -B ../../include/uapi/linux/bpf.h ../../../include/uapi/linux/bpf.h >/dev/null) \|\| \
	echo "Warning: Kernel ABI header at 'tools/include/uapi/linux/bpf.h' differs from latest version at 'include/uapi/linux/bpf.h'" >&2 )) \|\| true
	@(test -f ../../include/uapi/linux/bpf_common.h -a -f ../../../include/uapi/linux/bpf_common.h && ( \
	(diff -B ../../include/uapi/linux/bpf_common.h ../../../include/uapi/linux/bpf_common.h >/dev/null) \|\| \
	echo "Warning: Kernel ABI header at 'tools/include/uapi/linux/bpf_common.h' differs from latest version at 'include/uapi/linux/bpf_common.h'" >&2 )) \|\| true
	@(test -f ../../include/uapi/linux/netlink.h -a -f ../../../include/uapi/linux/netlink.h && ( \
	(diff -B ../../include/uapi/linux/netlink.h ../../../include/uapi/linux/netlink.h >/dev/null) \|\| \
	echo "Warning: Kernel ABI header at 'tools/include/uapi/linux/netlink.h' differs from latest version at 'include/uapi/linux/netlink.h'" >&2 )) \|\| true
	@(test -f ../../include/uapi/linux/if_link.h -a -f ../../../include/uapi/linux/if_link.h && ( \
	(diff -B ../../include/uapi/linux/if_link.h ../../../include/uapi/linux/if_link.h >/dev/null) \|\| \
	echo "Warning: Kernel ABI header at 'tools/include/uapi/linux/if_link.h' differs from latest version at 'include/uapi/linux/if_link.h'" >&2 )) \|\| true
	@(test -f ../../include/uapi/linux/if_xdp.h -a -f ../../../include/uapi/linux/if_xdp.h && ( \
	(diff -B ../../include/uapi/linux/if_xdp.h ../../../include/uapi/linux/if_xdp.h >/dev/null) \|\| \
	echo "Warning: Kernel ABI header at 'tools/include/uapi/linux/if_xdp.h' differs from latest version at 'include/uapi/linux/if_xdp.h'" >&2 )) \|\| true
	$(Q)$(MAKE) $(build)=libbpf OUTPUT=$(SHARED_OBJDIR) CFLAGS="$(CFLAGS) $(SHLIB_FLAGS)"

	$(BPF_IN_STATIC): force elfdep zdep bpfdep $(BPF_HELPER_DEFS)
	$(Q)$(MAKE) $(build)=libbpf OUTPUT=$(STATIC_OBJDIR)

	$(BPF_HELPER_DEFS): $(srctree)/tools/include/uapi/linux/bpf.h
	$(QUIET_GEN)$(srctree)/scripts/bpf_helpers_doc.py --header \
	--file $(srctree)/tools/include/uapi/linux/bpf.h > $(BPF_HELPER_DEFS)

	$(OUTPUT)libbpf.so: $(OUTPUT)libbpf.so.$(LIBBPF_VERSION)

	$(OUTPUT)libbpf.so.$(LIBBPF_VERSION): $(BPF_IN_SHARED)
	$(QUIET_LINK)$(CC) $(LDFLAGS) \
	--shared -Wl,-soname,libbpf.so.$(LIBBPF_MAJOR_VERSION) \
	-Wl,--version-script=$(VERSION_SCRIPT) $^ -lelf -lz -o $@
	@ln -sf $(@F) $(OUTPUT)libbpf.so
	@ln -sf $(@F) $(OUTPUT)libbpf.so.$(LIBBPF_MAJOR_VERSION)

	$(OUTPUT)libbpf.a: $(BPF_IN_STATIC)
	$(QUIET_LINK)$(RM) $@; $(AR) rcs $@ $^

	$(OUTPUT)libbpf.pc:
	$(QUIET_GEN)sed -e "s\|@PREFIX@\|$(prefix)\|" \
	-e "s\|@LIBDIR@\|$(libdir_SQ)\|" \
	-e "s\|@VERSION@\|$(LIBBPF_VERSION)\|" \
	< libbpf.pc.template > $@

	check: check_abi

	check_abi: $(OUTPUT)libbpf.so
	@if [ "$(GLOBAL_SYM_COUNT)" != "$(VERSIONED_SYM_COUNT)" ]; then \
	echo "Warning: Num of global symbols in $(BPF_IN_SHARED)" \
	"($(GLOBAL_SYM_COUNT)) does NOT match with num of" \
	"versioned symbols in $^ ($(VERSIONED_SYM_COUNT))." \
	"Please make sure all LIBBPF_API symbols are" \
	"versioned in $(VERSION_SCRIPT)." >&2; \
	readelf -s --wide $(BPF_IN_SHARED) \| \
	cut -d "@" -f1 \| sed 's/_v[0-9]_[0-9]_[0-9].*//' \| \
	sed 's/\[.*\]//' \| \
	awk '/GLOBAL/ && /DEFAULT/ && !/UND/ {print $$NF}'\| \
	sort -u > $(OUTPUT)libbpf_global_syms.tmp; \
	readelf -s --wide $(OUTPUT)libbpf.so \| \
	grep -Eo '[^ ]+@LIBBPF_' \| cut -d@ -f1 \| \
	sort -u > $(OUTPUT)libbpf_versioned_syms.tmp; \
	diff -u $(OUTPUT)libbpf_global_syms.tmp \
	$(OUTPUT)libbpf_versioned_syms.tmp; \
	rm $(OUTPUT)libbpf_global_syms.tmp \
	$(OUTPUT)libbpf_versioned_syms.tmp; \
	exit 1; \
	fi

	define do_install_mkdir
	if [ ! -d '$(DESTDIR_SQ)$1' ]; then \
	$(INSTALL) -d -m 755 '$(DESTDIR_SQ)$1'; \
	fi
	endef

	define do_install
	if [ ! -d '$(DESTDIR_SQ)$2' ]; then \
	$(INSTALL) -d -m 755 '$(DESTDIR_SQ)$2'; \
	fi; \
	$(INSTALL) $1 $(if $3,-m $3,) '$(DESTDIR_SQ)$2'
	endef

	install_lib: all_cmd
	$(call QUIET_INSTALL, $(LIB_TARGET)) \
	$(call do_install_mkdir,$(libdir_SQ)); \
	cp -fpR $(LIB_FILE) $(DESTDIR)$(libdir_SQ)

	install_headers: $(BPF_HELPER_DEFS)
	$(call QUIET_INSTALL, headers) \
	$(call do_install,bpf.h,$(prefix)/include/bpf,644); \
	$(call do_install,libbpf.h,$(prefix)/include/bpf,644); \
	$(call do_install,btf.h,$(prefix)/include/bpf,644); \
	$(call do_install,libbpf_util.h,$(prefix)/include/bpf,644); \
	$(call do_install,libbpf_common.h,$(prefix)/include/bpf,644); \
	$(call do_install,xsk.h,$(prefix)/include/bpf,644); \
	$(call do_install,bpf_helpers.h,$(prefix)/include/bpf,644); \
	$(call do_install,$(BPF_HELPER_DEFS),$(prefix)/include/bpf,644); \
	$(call do_install,bpf_tracing.h,$(prefix)/include/bpf,644); \
	$(call do_install,bpf_endian.h,$(prefix)/include/bpf,644); \
	$(call do_install,bpf_core_read.h,$(prefix)/include/bpf,644);

	install_pkgconfig: $(PC_FILE)
	$(call QUIET_INSTALL, $(PC_FILE)) \
	$(call do_install,$(PC_FILE),$(libdir_SQ)/pkgconfig,644)

	install: install_lib install_pkgconfig

	### Cleaning rules

	config-clean:
	$(call QUIET_CLEAN, config)
	$(Q)$(MAKE) -C $(srctree)/tools/build/feature/ clean >/dev/null

	clean:
	$(call QUIET_CLEAN, libbpf) $(RM) -rf $(CMD_TARGETS) \
	~ ..d .*.cmd LIBBPF-CFLAGS $(BPF_HELPER_DEFS) \
	$(SHARED_OBJDIR) $(STATIC_OBJDIR) \
	$(addprefix $(OUTPUT), \
	.o .a .so .so.$(LIBBPF_MAJOR_VERSION) *.pc)
	$(call QUIET_CLEAN, core-gen) $(RM) $(OUTPUT)FEATURE-DUMP.libbpf



	PHONY += force elfdep zdep bpfdep cscope tags
	force:

	elfdep:
	@if [ "$(feature-libelf)" != "1" ]; then echo "No libelf found"; exit 1 ; fi

	zdep:
	@if [ "$(feature-zlib)" != "1" ]; then echo "No zlib found"; exit 1 ; fi

	bpfdep:
	@if [ "$(feature-bpf)" != "1" ]; then echo "BPF API too old"; exit 1 ; fi

	cscope:
	ls .c .h > cscope.files
	cscope -b -q -I $(srctree)/include -f cscope.out

	tags:
	rm -f TAGS tags
	ls .c .h \| xargs $(TAGS_PROG) -a

	# Declare the contents of the .PHONY variable as phony. We keep that
	# information in a variable so we can use it in if_changed and friends.
	.PHONY: $(PHONY)

	# Delete partially updated (corrupted) files on error
	.DELETE_ON_ERROR: