[TheFreeNetwork] Do not allow lower priority protocols to handle remote actors already handled by the higher ones

lib/exceptions/alreadyhandledexception.php

@@ -0,0 +1,40 @@
+<?php
+// This file is part of GNU social - https://www.gnu.org/software/social
+//
+// GNU social is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// GNU social is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with GNU social.  If not, see <http://www.gnu.org/licenses/>.
+/**
+ * Class for exception thrown when something was already handled.
+ * Useful to use as a lock when handling a same something in different queues and only one should be attended
+ *
+ * @category  Exception
+ * @author    Diogo Cordeiro <diogo@fc.up.pt>
+ * @copyright 2020 Free Software Foundation, Inc http://www.fsf.org
+ * @license   https://www.gnu.org/licenses/agpl.html GNU AGPL v3 or later
+ */
+
+defined('GNUSOCIAL') || die();
+
+/**
+ * Exception thrown when something was already handled.
+ *
+ * @copyright 2019 Free Software Foundation, Inc http://www.fsf.org
+ * @license   https://www.gnu.org/licenses/agpl.html GNU AGPL v3 or later
+ */
+class AlreadyHandledException extends ServerException
+{
+    public function __construct($msg)
+    {
+        parent::__construct($msg, 202);
+    }
+}