blob: 85787d92a3ed06ee4dc9e7d94ea8d119c1550098 [file] [log] [blame]
// Copyright 2013 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 "base/macros.h"
#include "base/memory/ref_counted.h"
#include "ipc/ipc_sender.h"
namespace base {
class TaskRunner;
namespace IPC {
class MessageFilter;
namespace content {
class ThreadSafeSender;
// A base class for implementing IPC MessageFilter's that run on a different
// thread or TaskRunner than the main thread.
class ChildMessageFilter
: public base::RefCountedThreadSafe<ChildMessageFilter>,
public IPC::Sender {
// IPC::Sender implementation. Can be called on any threads.
bool Send(IPC::Message* message) override;
// If implementers want to run OnMessageReceived on a different task
// runner it should override this and return the TaskRunner for the message.
// Returning NULL runs OnMessageReceived() on the current IPC thread.
virtual base::TaskRunner* OverrideTaskRunnerForMessage(
const IPC::Message& msg) = 0;
// If OverrideTaskRunnerForMessage is overriden and returns non-null
// this will be called on the returned TaskRunner.
virtual bool OnMessageReceived(const IPC::Message& msg) = 0;
// This method is called when WorkerTaskRunner::PostTask() returned false
// for the target thread. Note that there's still a little chance that
// PostTask() returns true but OnMessageReceived() is never called on the
// target thread. By default this does nothing.
virtual void OnStaleMessageReceived(const IPC::Message& msg) {}
~ChildMessageFilter() override;
class Internal;
friend class ChildThreadImpl;
friend class RenderThreadImpl;
friend class WorkerThread;
friend class base::RefCountedThreadSafe<ChildMessageFilter>;
IPC::MessageFilter* GetFilter();
// This implements IPC::MessageFilter to hide the actual filter methods from
// child classes.
Internal* internal_;
scoped_refptr<ThreadSafeSender> thread_safe_sender_;
} // namespace content