cmake: add pkgconfig (#493)

CMakeLists.txt

@@ -12,7 +12,12 @@
 
 cmake_minimum_required(VERSION 3.7)
 
-project(re VERSION 2.6.1 LANGUAGES C)
+project(re
+  VERSION 2.6.1
+  LANGUAGES C
+  HOMEPAGE_URL https://github.com/baresip/re
+  DESCRIPTION "Generic library for real-time communications"
+)
 
 set(PROJECT_SOVERSION 8) # bump if ABI breaks
 
@@ -554,6 +559,18 @@ set_target_properties(re PROPERTIES OUTPUT_NAME "re-static")
 endif()
 
 
+##############################################################################
+#
+# Packaging section
+#
+
+if(CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR)
+  add_subdirectory(packaging)
+endif()
+
+configure_file(packaging/libre.pc.in libre.pc @ONLY)
+
+
 ##############################################################################
 #
 # Install section
@@ -582,11 +599,6 @@ install(FILES cmake/re-config.cmake
   DESTINATION ${CMAKE_INSTALL_LIBDIR}/cmake/re
 )
 
-##############################################################################
-#
-# Packaging section
-#
-
-if(CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR)
-  add_subdirectory(packaging)
-endif()
+install(FILES libre.pc
+  DESTINATION ${CMAKE_INSTALL_LIBDIR}/pkgconfig
+)

packaging/libre.pc.in

@@ -0,0 +1,12 @@
+prefix="@CMAKE_INSTALL_PREFIX@"
+exec_prefix=${prefix}
+libdir={$prefix}/lib
+includedir=${prefix}/include/re
+
+Name: @PROJECT_NAME@
+Description: @CMAKE_PROJECT_DESCRIPTION@
+Version: @PROJECT_VERSION@
+URL: @CMAKE_PROJECT_HOMEPAGE_URL@
+Libs: -L${libdir} -lre
+Libs.private: -L${libdir} -lre -ldl -lssl -lcrypto -lz -lpthread
+Cflags: -I${includedir}