miniupnpc/CMakeLists.txt: generate and install miniupnpc.pc

fixes #574

miniupnpc/CMakeLists.txt

@@ -219,6 +219,8 @@ if (UPNPC_BUILD_TESTS)
 # set (UPNPC_INSTALL_TARGETS ${UPNPC_INSTALL_TARGETS} testminixml minixmlvalid testupnpreplyparse testigddescparse testminiwget)
 endif ()
 
+configure_file(miniupnpc.pc.in miniupnpc.pc @ONLY)
+
 if (NOT UPNPC_NO_INSTALL)
   install (FILES
     include/miniupnpc.h
@@ -237,6 +239,10 @@ if (NOT UPNPC_NO_INSTALL)
   install(FILES miniupnpc-config.cmake
     DESTINATION ${CMAKE_INSTALL_LIBDIR}/cmake/miniupnpc
   )
+
+  install(FILES ${CMAKE_CURRENT_BINARY_DIR}/miniupnpc.pc
+    DESTINATION ${CMAKE_INSTALL_LIBDIR}/pkgconfig
+  )
 endif()
 
 # vim: ts=2:sw=2:expandtab

miniupnpc/miniupnpc.pc.in

@@ -0,0 +1,18 @@
+# this template is filled-in by CMake `configure_file(... @ONLY)`
+# the `@....@` are filled in by CMake configure_file(), 
+# from variables set in your CMakeLists.txt or by CMake itself
+#
+# Good tutoral for understanding .pc files: 
+# https://people.freedesktop.org/~dbn/pkg-config-guide.html
+
+prefix="@CMAKE_INSTALL_PREFIX@"
+exec_prefix="${prefix}"
+libdir="${prefix}/lib"
+includedir="${prefix}/include"
+
+Name: @PROJECT_NAME@
+Description: @CMAKE_PROJECT_DESCRIPTION@
+URL: @CMAKE_PROJECT_HOMEPAGE_URL@
+Version: @PROJECT_VERSION@
+Libs: -L"${libdir}" -lminiupnpc
+Cflags: -I"${includedir}"