client: add function client_is_local()

src/client.h

@@ -45,6 +45,17 @@ bool client_is_expired(const struct client *client);
 G_GNUC_PURE
 int client_get_uid(const struct client *client);
 
+/**
+ * Is this client running on the same machine, connected with a local
+ * (UNIX domain) socket?
+ */
+G_GNUC_PURE
+static inline bool
+client_is_local(const struct client *client)
+{
+	return client_get_uid(client) > 0;
+}
+
 G_GNUC_PURE
 unsigned client_get_permission(const struct client *client);
 

src/command.c

@@ -451,7 +451,7 @@ static enum command_return
 handle_urlhandlers(struct client *client,
 		   G_GNUC_UNUSED int argc, G_GNUC_UNUSED char *argv[])
 {
-	if (client_get_uid(client) > 0)
+	if (client_is_local(client))
 		client_puts(client, "handler: file://\n");
 	print_supported_uri_schemes(client);
 	return COMMAND_RETURN_OK;