Author: Luca Boccassi <bluca@debian.org>
Description: generate pkg-config file for libbpf
 Generate a libbpf.pc file at build time so that users can rely
 on pkg-config to find the library, its CFLAGS and LDFLAGS.
Origin: https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git/commit/?id=dd399ac9e343c7573c47d6820e4a23013c54749d
Applied-Upstream: yes
--- a/tools/lib/bpf/.gitignore
+++ b/tools/lib/bpf/.gitignore
@@ -1,2 +1,3 @@
 libbpf_version.h
+libbpf.pc
 FEATURE-DUMP.libbpf
--- a/tools/lib/bpf/Makefile
+++ b/tools/lib/bpf/Makefile
@@ -93,6 +93,7 @@
 LIBBPF_VERSION=$(shell make --no-print-directory -sC ../../.. kernelversion)
 
 LIB_FILE = libbpf.a libbpf.so.$(LIBBPF_VERSION)
+PC_FILE = libbpf.pc
 
 OBJ		= $@
 N		=
@@ -136,8 +137,9 @@
 
 BPF_IN    := $(OUTPUT)libbpf-in.o
 LIB_FILE := $(addprefix $(OUTPUT),$(LIB_FILE))
+PC_FILE := $(addprefix $(OUTPUT),$(PC_FILE))
 
-CMD_TARGETS = $(LIB_FILE)
+CMD_TARGETS = $(LIB_FILE) $(PC_FILE)
 
 TARGETS = $(CMD_TARGETS)
 
@@ -166,6 +168,12 @@
 $(OUTPUT)libbpf.a: $(BPF_IN)
 	$(QUIET_LINK)$(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 > $@
+
 define do_install
 	if [ ! -d '$(DESTDIR_SQ)$2' ]; then		\
 		$(INSTALL) -d -m 755 '$(DESTDIR_SQ)$2';	\
@@ -184,7 +192,12 @@
 		$(call do_install,libbpf.h,$(prefix)/include/bpf,644);
 		$(call do_install,btf.h,$(prefix)/include/bpf,644);
 
-install: install_lib
+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
 
@@ -193,7 +206,7 @@
 	$(Q)$(MAKE) -C $(srctree)/tools/build/feature/ clean >/dev/null
 
 clean:
-	$(call QUIET_CLEAN, libbpf) $(RM) *.o *~ $(TARGETS) *.a *.so .*.d .*.cmd \
+	$(call QUIET_CLEAN, libbpf) $(RM) *.o *~ $(TARGETS) *.a *.so .*.d .*.cmd *.pc \
 		$(RM) LIBBPF-CFLAGS
 	$(call QUIET_CLEAN, core-gen) $(RM) $(OUTPUT)FEATURE-DUMP.libbpf
 
--- /dev/null
+++ b/tools/lib/bpf/libbpf.pc.template
@@ -0,0 +1,12 @@
+# SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
+
+prefix=@PREFIX@
+libdir=@LIBDIR@
+includedir=${prefix}/include
+
+Name: libbpf
+Description: BPF library
+Version: @VERSION@
+Libs: -L${libdir} -lbpf
+Requires.private: libelf
+Cflags: -I${includedir}