Generate and install a pkg-config file. (#142)

* Generate and install a pkg-config file.

* Use Makefile libdir and includedir for pkg-config.

This splits the prefix out from these variables, so that
the same variables can be used to construct the pkg-config
file.

* Update the manifest for installation of pkg-config file.

* Revert "Use Makefile libdir and includedir for pkg-config."

This reverts commit a4cd6dc.

* Use Makefile libdir and includedir for pkg-config.

This splits the prefix out from these variables, so that
the same variables can be used to construct the pkg-config
file.

MANIFEST

@@ -5,3 +5,5 @@ lib/libutf8proc.a
 lib/libutf8proc.so -> libutf8proc.so.2.2.0
 lib/libutf8proc.so.2 -> libutf8proc.so.2.2.0
 lib/libutf8proc.so.2.2.0
+lib/pkgconfig/
+lib/pkgconfig/libutf8proc.pc

Makefile

@@ -36,6 +36,10 @@ endif
 prefix=/usr/local
 libdir=$(prefix)/lib
 includedir=$(prefix)/include
+pkgconfigdir=$(libdir)/pkgconfig
+
+pkglibdir=$(libdir:$(prefix)/%=%)
+pkgincludedir=$(includedir:$(prefix)/%=%)
 
 # meta targets
 
@@ -45,6 +49,7 @@ all: libutf8proc.a libutf8proc.$(SHLIB_EXT)
 
 clean:
 	rm -f utf8proc.o libutf8proc.a libutf8proc.$(SHLIB_VERS_EXT) libutf8proc.$(SHLIB_EXT)
+	rm -f libutf8proc.pc
 ifneq ($(OS),Darwin)
 	rm -f libutf8proc.so.$(MAJOR)
 endif
@@ -86,12 +91,22 @@ libutf8proc.$(MAJOR).dylib: utf8proc.o
 libutf8proc.dylib: libutf8proc.$(MAJOR).dylib
 	ln -f -s libutf8proc.$(MAJOR).dylib $@
 
-install: libutf8proc.a libutf8proc.$(SHLIB_EXT) libutf8proc.$(SHLIB_VERS_EXT)
+libutf8proc.pc: libutf8proc.pc.in
+	sed \
+		-e 's#PREFIX#$(prefix)#' \
+		-e 's#LIBDIR#$(pkglibdir)#' \
+		-e 's#INCLUDEDIR#$(pkgincludedir)#' \
+		-e 's#VERSION#$(MAJOR).$(MINOR).$(PATCH)#' \
+		libutf8proc.pc.in > libutf8proc.pc
+
+install: libutf8proc.a libutf8proc.$(SHLIB_EXT) libutf8proc.$(SHLIB_VERS_EXT) libutf8proc.pc
 	mkdir -m 755 -p $(DESTDIR)$(includedir)
 	$(INSTALL) -m 644 utf8proc.h $(DESTDIR)$(includedir)
 	mkdir -m 755 -p $(DESTDIR)$(libdir)
 	$(INSTALL) -m 644 libutf8proc.a $(DESTDIR)$(libdir)
 	$(INSTALL) -m 755 libutf8proc.$(SHLIB_VERS_EXT) $(DESTDIR)$(libdir)
+	mkdir -m 755 -p $(DESTDIR)$(pkgconfigdir)
+	$(INSTALL) -m 644 libutf8proc.pc $(DESTDIR)$(pkgconfigdir)/libutf8proc.pc
 	ln -f -s libutf8proc.$(SHLIB_VERS_EXT) $(DESTDIR)$(libdir)/libutf8proc.$(SHLIB_EXT)
 ifneq ($(OS),Darwin)
 	ln -f -s libutf8proc.$(SHLIB_VERS_EXT) $(DESTDIR)$(libdir)/libutf8proc.so.$(MAJOR)

libutf8proc.pc.in

@@ -0,0 +1,10 @@
+prefix=PREFIX
+exec_prefix=${prefix}
+libdir=${prefix}/LIBDIR
+includedir=${prefix}/INCLUDEDIR
+
+Name: libutf8proc
+Description: UTF8 processing
+Version: VERSION
+Libs: -L${libdir} -lutf8proc
+Cflags: -I${includedir} -DUTF8PROC_EXPORTS