1 files changed, 38 insertions, 0 deletions
diff --git a/xpcom/threads/nsICancelableRunnable.h b/xpcom/threads/nsICancelableRunnable.h
new file mode 100644
index 000000000..5ae9f5b14
--- /dev/null
+++ b/xpcom/threads/nsICancelableRunnable.h
@@ -0,0 +1,38 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsICancelableRunnable_h__
+#define nsICancelableRunnable_h__
+
+#include "nsISupports.h"
+
+#define NS_ICANCELABLERUNNABLE_IID \
+{ 0xde93dc4c, 0x5eea, 0x4eb7, \
+{ 0xb6, 0xd1, 0xdb, 0xf1, 0xe0, 0xce, 0xf6, 0x5c } }
+
+class nsICancelableRunnable : public nsISupports
+{
+public:
+  NS_DECLARE_STATIC_IID_ACCESSOR(NS_ICANCELABLERUNNABLE_IID)
+
+  /*
+   * Cancels a pending task.  If the task has already been executed this will
+   * be a no-op.  Calling this method twice is considered an error.
+   *
+   * @throws NS_ERROR_UNEXPECTED
+   *   Indicates that the runnable has already been canceled.
+   */
+  virtual nsresult Cancel() = 0;
+
+protected:
+  nsICancelableRunnable() { }
+  virtual ~nsICancelableRunnable() {}
+};
+
+NS_DEFINE_STATIC_IID_ACCESSOR(nsICancelableRunnable,
+                              NS_ICANCELABLERUNNABLE_IID)
+
+#endif // nsICancelableRunnable_h__