1 files changed, 40 insertions, 0 deletions
diff --git a/dom/ipc/PVsync.ipdl b/dom/ipc/PVsync.ipdl
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+++ b/dom/ipc/PVsync.ipdl
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+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* 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/. */
+
+include protocol PBackground;
+include protocol PBrowser;
+include "mozilla/layers/LayersMessageUtils.h";
+
+using class mozilla::TimeStamp from "mozilla/TimeStamp.h";
+using mozilla::VsyncEvent from "mozilla/VsyncDispatcher.h";
+
+namespace mozilla {
+namespace dom {
+
+/*
+ * The PVsync is a sub-protocol in PBackground or PBrowser and it is used to
+ * notify the vsync event from chrome to content process. It also provides the
+ * interfaces for content to observe/unobserve vsync event notifications.
+ */
+async protocol PVsync
+{
+  manager PBackground or PBrowser;
+
+child:
+  // Send vsync event and vsync rate from chrome to content process.
+  [Compress, Priority=vsync] async Notify(VsyncEvent aVsync, float aVsyncRate);
+
+parent:
+  // Content process use these messages to acquire the vsync event.
+  async Observe();
+  async Unobserve();
+
+  // This message is never sent. Each PVsync actor will stay alive as long as
+  // its PBackground or PBrowser manager.
+  async __delete__();
+};
+
+} // namespace dom
+} // namespace mozilla