1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/ipc/chromium/src/chrome/common/message_router.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,60 @@
1.4 +// Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
1.5 +// Use of this source code is governed by a BSD-style license that can be
1.6 +// found in the LICENSE file.
1.7 +
1.8 +#ifndef CHROME_COMMON_MESSAGE_ROUTER_H__
1.9 +#define CHROME_COMMON_MESSAGE_ROUTER_H__
1.10 +
1.11 +#include "base/id_map.h"
1.12 +#include "chrome/common/ipc_channel.h"
1.13 +
1.14 +// The MessageRouter handles all incoming messages sent to it by routing them
1.15 +// to the correct listener. Routing is based on the Message's routing ID.
1.16 +// Since routing IDs are typically assigned asynchronously by the browser
1.17 +// process, the MessageRouter has the notion of pending IDs for listeners that
1.18 +// have not yet been assigned a routing ID.
1.19 +//
1.20 +// When a message arrives, the routing ID is used to index the set of routes to
1.21 +// find a listener. If a listener is found, then the message is passed to it.
1.22 +// Otherwise, the message is ignored if its routing ID is not equal to
1.23 +// MSG_ROUTING_CONTROL.
1.24 +//
1.25 +// The MessageRouter supports the IPC::Message::Sender interface for outgoing
1.26 +// messages, but does not define a meaningful implementation of it. The
1.27 +// subclass of MessageRouter is intended to provide that if appropriate.
1.28 +//
1.29 +// The MessageRouter can be used as a concrete class provided its Send method
1.30 +// is not called and it does not receive any control messages.
1.31 +
1.32 +class MessageRouter : public IPC::Channel::Listener,
1.33 + public IPC::Message::Sender {
1.34 + public:
1.35 + MessageRouter() {}
1.36 + virtual ~MessageRouter() {}
1.37 +
1.38 + // Implemented by subclasses to handle control messages
1.39 + virtual void OnControlMessageReceived(const IPC::Message& msg);
1.40 +
1.41 + // IPC::Channel::Listener implementation:
1.42 + virtual void OnMessageReceived(const IPC::Message& msg);
1.43 +
1.44 + // Like OnMessageReceived, except it only handles routed messages. Returns
1.45 + // true if the message was dispatched, or false if there was no listener for
1.46 + // that route id.
1.47 + virtual bool RouteMessage(const IPC::Message& msg);
1.48 +
1.49 + // IPC::Message::Sender implementation:
1.50 + virtual bool Send(IPC::Message* msg);
1.51 +
1.52 + // Called to add/remove a listener for a particular message routing ID.
1.53 + void AddRoute(int32_t routing_id, IPC::Channel::Listener* listener);
1.54 + void RemoveRoute(int32_t routing_id);
1.55 +
1.56 + private:
1.57 + // A list of all listeners with assigned routing IDs.
1.58 + IDMap<IPC::Channel::Listener> routes_;
1.59 +
1.60 + DISALLOW_EVIL_CONSTRUCTORS(MessageRouter);
1.61 +};
1.62 +
1.63 +#endif // CHROME_COMMON_MESSAGE_ROUTER_H__
