+_public_ int sd_bus_path_encode(const char *prefix, const char *external_id, char **ret_path) {
+ _cleanup_free_ char *e = NULL;
+ char *ret;
+
+ assert_return(object_path_is_valid(prefix), -EINVAL);
+ assert_return(external_id, -EINVAL);
+ assert_return(ret_path, -EINVAL);
+
+ e = bus_label_escape(external_id);
+ if (!e)
+ return -ENOMEM;
+
+ ret = strjoin(prefix, "/", e, NULL);
+ if (!ret)
+ return -ENOMEM;
+
+ *ret_path = ret;
+ return 0;