michael@0: /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #include "nsIRunnable.idl"
michael@0: 
michael@0: /**
michael@0:  * Represents a task which can be dispatched to a thread for execution and
michael@0:  * which can be cancelled if necessary.
michael@0:  */
michael@0: 
michael@0: [scriptable, uuid(de93dc4c-5eea-4eb7-b6d1-dbf1e0cef65c)]
michael@0: interface nsICancelableRunnable : nsIRunnable
michael@0: {
michael@0:     /**
michael@0:      * Cancels a pending task.  If the task has already been executed this will
michael@0:      * be a no-op.  Calling this method twice is considered an error.
michael@0:      *
michael@0:      * @throws NS_ERROR_UNEXPECTED
michael@0:      *   Indicates that the runnable has already been canceled.
michael@0:      */
michael@0:     void cancel();
michael@0: };