cmake: add support for building services with config files

cmake/Sysroot.cmake

@@ -155,6 +155,40 @@ function(sysroot_add_program)
 	set_property(GLOBAL PROPERTY sysroot_target_list ${sysroot_targets} ${sysroot_target_name})
 endfunction(sysroot_add_program)
 
+function(sysroot_add_service)
+	set(options)
+	set(one_value_args NAME BIN_DIR SVC_DIR)
+	set(multi_value_args)
+
+	cmake_parse_arguments(PARSE_ARGV 0 arg
+		"${options}"
+		"${one_value_args}"
+		"${multi_value_args}")
+
+	set(target_name ${arg_NAME})
+	set(sysroot_target_name _sysroot-${target_name})
+
+	get_property(sysroot_targets GLOBAL PROPERTY sysroot_target_list)
+	get_property(cfg_file TARGET ${arg_NAME} PROPERTY service_cfg_path)
+	list(LENGTH sysroot_targets nr_sysroot_targets)
+	if (${nr_sysroot_targets} GREATER 0)
+		math(EXPR serialiser_index "${nr_sysroot_targets}-1")
+		list(GET sysroot_targets ${serialiser_index} serialiser)
+	endif ()
+
+	add_custom_target(${sysroot_target_name}
+		COMMAND	${Python_EXECUTABLE} ${sysroot_tool}
+			add-binary ${sysroot_manifest} ${target_name}
+			${arg_BIN_DIR} $<TARGET_FILE:${target_name}>
+		COMMAND	${Python_EXECUTABLE} ${sysroot_tool}
+			add-binary ${sysroot_manifest} ${target_name}-cfg
+			${arg_SVC_DIR} ${cfg_file}
+		COMMENT "Preparing sysroot component: ${target_name}"
+		DEPENDS ${target_name} ${serialiser})
+
+	set_property(GLOBAL PROPERTY sysroot_target_list ${sysroot_targets} ${sysroot_target_name})
+endfunction(sysroot_add_service)
+
 function(sysroot_add_file)
 	set(options)
 	set(one_value_args ID SRC_PATH DEST_DIR)