Delegate WebSocket message handlers to the loading task runner

content/child/websocket_message_filter.cc

Index: content/child/websocket_message_filter.cc
diff --git a/content/child/websocket_message_filter.cc b/content/child/websocket_message_filter.cc
new file mode 100644
index 0000000000000000000000000000000000000000..9f2b52ab9c058559081f4ad29d0d8db449431dd5
--- /dev/null
+++ b/content/child/websocket_message_filter.cc
@@ -0,0 +1,30 @@
+// Copyright 2016 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.
+
+#include "content/child/websocket_message_filter.h"
+
+#include "base/bind.h"
+#include "base/single_thread_task_runner.h"
+#include "content/child/websocket_dispatcher.h"
+#include "ipc/ipc_message.h"
+
+namespace content {
+
+WebSocketMessageFilter::WebSocketMessageFilter(
+    WebSocketDispatcher* websocket_dispatcher)
+  : websocket_dispatcher_(websocket_dispatcher) {}
+
+WebSocketMessageFilter::~WebSocketMessageFilter() {}
+
+bool WebSocketMessageFilter::OnMessageReceived(const IPC::Message& message) {

[yhirano, 2016/05/25 10:39:52]

Does this function run on the IO thread? If so, can you add an assertion?

[yhirano, 2016/05/25 11:34:52]

Hmm, it seems there is no easy way to check that. I retract this comment.

+  if (!websocket_dispatcher_->CanHandleMessage(message))
+    return false;
+  loading_task_runner_->PostTask(FROM_HERE, base::Bind(
+      base::IgnoreResult(&WebSocketDispatcher::OnMessageReceived),
+      base::Unretained(websocket_dispatcher_),

[kinuko, 2016/05/25 09:30:53]

It's not obvious who guarantees websocket_dispatcher_ is still alive when the
posted task runs?  If it's really safe can you add a comment here and at the raw
ptr in .h?  Or if it's not the case I think we should post task to |this| or to
static function first and make sure if websocket_dispatcher_ is alive via
weakptr etc

[hajimehoshi, 2016/05/25 12:05:02]

IIUC websocket_dispatcher_ is owned by a RenderThreadImpl, which lives while the
renderer process lives.  Done.

+      message));
+  return true;
+}
+
+}  // namespace content