Add CMake module to parse IDL files on Windows

cmake/Modules/IDLFileHelper.cmake

@@ -0,0 +1,65 @@
+macro(add_idl_files generated_files)
+	foreach(filename ${ARGN})
+		get_filename_component(file_we ${filename} NAME_WE)
+		get_filename_component(file_path ${filename} PATH)
+
+		set(file_c ${file_we}_i.c)
+		set(file_h ${file_we}.h)
+		set(bin_file_h ${CMAKE_CURRENT_BINARY_DIR}/${file_h})
+		set(bin_file_c ${CMAKE_CURRENT_BINARY_DIR}/${file_c})
+
+		if(MSVC)
+			add_custom_command(
+				OUTPUT ${bin_file_h} ${bin_file_c}
+				DEPENDS ${filename}
+				COMMAND midl /h ${file_h} /iid ${file_c} /notlb ${CMAKE_CURRENT_SOURCE_DIR}/${filename}
+				WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR})
+		else()
+			execute_process(COMMAND echo
+				COMMAND ${CMAKE_C_COMPILER} -v -x c++ -E -
+				ERROR_VARIABLE cpp_inc_output
+				OUTPUT_QUIET
+				ERROR_STRIP_TRAILING_WHITESPACE)
+
+			string(REPLACE ";" " " include_dirs ${cpp_inc_output})
+			string(REPLACE "\n" ";" include_dirs ${cpp_inc_output})
+
+			set(include_params)
+			foreach(include_dir ${include_dirs})
+				string(SUBSTRING ${include_dir} 0 1 first_char)
+				if(${first_char} STREQUAL " ")
+					string(LENGTH "${include_dir}" include_dir_len)
+					math(EXPR include_dir_len "${include_dir_len} - 1")
+					string(SUBSTRING ${include_dir} 1 ${include_dir_len} include_dir)
+					set(include_params "-I\"${include_dir}\" ${include_params}")
+				endif()
+			endforeach()
+
+			if(WIN32)
+				separate_arguments(include_params WINDOWS_COMMAND ${include_params})
+			endif()
+
+			add_custom_command(
+				OUTPUT ${file_h}
+				DEPENDS ${filename}
+				COMMAND ${CMAKE_WIDL} ${include_params} -h -o ${file_h} ${CMAKE_CURRENT_SOURCE_DIR}/${filename}
+				WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR})
+
+			file(WRITE ${bin_file_c} "#include <initguid.h>\n#include <${file_h}>\n")
+		endif()
+
+		set_source_files_properties(
+			${bin_file_h}
+			${bin_file_c}
+			PROPERTIES
+			GENERATED TRUE)
+
+		set(${generated_files} ${${generated_file}}
+			${bin_file_h}
+			${bin_file_c})
+
+		set_source_files_properties(${filename}
+			PROPERTIES
+			HEADER_FILE_ONLY TRUE)
+	endforeach(filename ${ARGN})
+endmacro(add_idl_files)