content: Pass IOSurface references using Mach IPC.

content/common/mac/io_surface_manager_messages.h

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CONTENT_COMMON_MAC_IO_SURFACE_MANAGER_MESSAGES_H_
+#define CONTENT_COMMON_MAC_IO_SURFACE_MANAGER_MESSAGES_H_
+
+// Mach IPC messages used for child processes.
+
+// Message IDs.
+// Note: we currently use __LINE__ to give unique IDs to messages.
+// They're unique since all messages are defined in this file.
+#define MACH_MESSAGE_ID() __LINE__
+
+namespace content {
+
+// Messages sent from the child process to the browser.
+
+struct IOSurfaceManagerHostMsg_RegisterIOSurface {

[Robert Sesek, 2015/05/15 21:45:05]

Each of these messages should have the

mach_msg_header_t header
mach_msg_body_t body
gpu::Mailbox mailbox
<data>

Rather than declaring those where you're calling mach_msg.

[reveman, 2015/05/18 18:15:39]

Done but gpu::Mailbox here gets ugly as it's not POD (need explicit ctor) so
changed it to mailbox_name[64].

+  enum { ID = MACH_MESSAGE_ID() };
+  mach_msg_port_descriptor_t io_surface_port;
+  int io_surface_id;
+  int client_id;
+};
+
+struct IOSurfaceManagerHostMsg_RegisterIOSurfaceReply {
+  enum { ID = MACH_MESSAGE_ID() };
+  boolean_t result;
+};
+
+struct IOSurfaceManagerHostMsg_UnregisterIOSurface {
+  enum { ID = MACH_MESSAGE_ID() };
+  int io_surface_id;
+  int client_id;
+};
+
+struct IOSurfaceManagerHostMsg_AcquireIOSurface {
+  enum { ID = MACH_MESSAGE_ID() };
+  int io_surface_id;
+};
+
+// Messages sent from the browser to the child process.
+
+struct IOSurfaceManagerMsg_RegisterIOSurfaceReply {
+  boolean_t result;
+};
+
+struct IOSurfaceManagerMsg_AcquireIOSurfaceReply {
+  mach_msg_port_descriptor_t io_surface_port;
+};
+
+}  // namespace content
+
+#endif  // CONTENT_COMMON_MAC_IO_SURFACE_MANAGER_MESSAGES_H_