[PATCH liburing 1/2] pkgconfig: install a liburing.pc file

[Stefan Hajnoczi <stefanha@redhat.com>]

pkg-config (https://pkgconfig.freedesktop.org/) makes it easier to build
applications that have library dependencies.  Libraries ship .pc files
containing the compiler and linker flags needed to build successfully.
This saves applications from hardcoding these details into their build
scripts, especially when these details can change between operating
systems or distributions.

To build a liburing application:

  gcc $(pkg-config --cflags --libs liburing) -o myapp myapp.c

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 Makefile       | 13 +++++++++++--
 .gitignore     |  2 ++
 liburing.pc.in | 12 ++++++++++++
 3 files changed, 25 insertions(+), 2 deletions(-)
 create mode 100644 liburing.pc.in

diff --git a/Makefile b/Makefile
index d42dd45..6755713 100644
--- a/Makefile
+++ b/Makefile
@@ -33,13 +33,22 @@ ifneq ($(MAKECMDGOALS),clean)
 include config-host.mak
 endif
 
-install:
+%.pc: %.pc.in
+	sed -e "s%@prefix@%$(prefix)%g" \
+	    -e "s%@libdir@%$(libdir)%g" \
+	    -e "s%@includedir@%$(includedir)%g" \
+	    -e "s%@NAME@%$(NAME)%g" \
+	    -e "s%@VERSION@%$(VERSION)%g" \
+	    $< >$@
+
+install: $(NAME).pc
 	@$(MAKE) -C src install prefix=$(DESTDIR)$(prefix) includedir=$(DESTDIR)$(includedir) libdir=$(DESTDIR)$(libdir)
+	$(INSTALL) -D -m 644 $(NAME).pc $(DESTDIR)$(libdir)/pkgconfig/$(NAME).pc
 	$(INSTALL) -m 755 -d $(DESTDIR)$(mandir)/man2
 	$(INSTALL) -m 644 man/*.2 $(DESTDIR)$(mandir)/man2
 
 clean:
-	@rm -f config-host.mak config-host.h cscope.out
+	@rm -f config-host.mak config-host.h cscope.out $(NAME).pc
 	@$(MAKE) -C src clean
 	@$(MAKE) -C test clean
 	@$(MAKE) -C examples clean
diff --git a/.gitignore b/.gitignore
index e292825..08ba0e0 100644
--- a/.gitignore
+++ b/.gitignore
@@ -12,3 +12,5 @@
 config-host.h
 config-host.mak
 config.log
+
+liburing.pc
diff --git a/liburing.pc.in b/liburing.pc.in
new file mode 100644
index 0000000..e621939
--- /dev/null
+++ b/liburing.pc.in
@@ -0,0 +1,12 @@
+prefix=@prefix@
+exec_prefix=${prefix}
+libdir=@libdir@
+includedir=@includedir@
+
+Name: @NAME@
+Version: @VERSION@
+Description: io_uring library
+URL: http://git.kernel.dk/cgit/liburing/
+
+Libs: -L${libdir} -luring
+Cflags: -I${includedir}
-- 
2.21.0