15821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// Copyright (c) 2012 The Chromium Authors. All rights reserved. 25821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// Use of this source code is governed by a BSD-style license that can be 35821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// found in the LICENSE file. 45821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 55821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#ifndef CONTENT_COMMON_MESSAGE_ROUTER_H_ 65821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#define CONTENT_COMMON_MESSAGE_ROUTER_H_ 75821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 85821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include "base/id_map.h" 95821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include "ipc/ipc_listener.h" 105821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include "ipc/ipc_sender.h" 115821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 125821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// The MessageRouter handles all incoming messages sent to it by routing them 135821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// to the correct listener. Routing is based on the Message's routing ID. 145821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// Since routing IDs are typically assigned asynchronously by the browser 155821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// process, the MessageRouter has the notion of pending IDs for listeners that 165821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// have not yet been assigned a routing ID. 175821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// 185821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// When a message arrives, the routing ID is used to index the set of routes to 195821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// find a listener. If a listener is found, then the message is passed to it. 205821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// Otherwise, the message is ignored if its routing ID is not equal to 215821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// MSG_ROUTING_CONTROL. 225821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// 235821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// The MessageRouter supports the IPC::Sender interface for outgoing messages, 245821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// but does not define a meaningful implementation of it. The subclass of 255821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// MessageRouter is intended to provide that if appropriate. 265821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// 275821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// The MessageRouter can be used as a concrete class provided its Send method 285821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// is not called and it does not receive any control messages. 295821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 305821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)namespace content { 315821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 325821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)class MessageRouter : public IPC::Listener, public IPC::Sender { 335821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) public: 345821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) MessageRouter(); 355821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) virtual ~MessageRouter(); 365821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 375821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // Implemented by subclasses to handle control messages 385821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) virtual bool OnControlMessageReceived(const IPC::Message& msg); 395821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 405821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // IPC::Listener implementation: 415821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) virtual bool OnMessageReceived(const IPC::Message& msg) OVERRIDE; 425821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 435821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // Like OnMessageReceived, except it only handles routed messages. Returns 445821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // true if the message was dispatched, or false if there was no listener for 455821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // that route id. 465821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) virtual bool RouteMessage(const IPC::Message& msg); 475821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 485821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // IPC::Sender implementation: 495821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) virtual bool Send(IPC::Message* msg) OVERRIDE; 505821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 51c5cede9ae108bb15f6b7a8aea21c7e1fefa2834cBen Murdoch // Called to add a listener for a particular message routing ID. 52c5cede9ae108bb15f6b7a8aea21c7e1fefa2834cBen Murdoch // Returns true if succeeded. 53c5cede9ae108bb15f6b7a8aea21c7e1fefa2834cBen Murdoch bool AddRoute(int32 routing_id, IPC::Listener* listener); 54c5cede9ae108bb15f6b7a8aea21c7e1fefa2834cBen Murdoch 55c5cede9ae108bb15f6b7a8aea21c7e1fefa2834cBen Murdoch // Called to remove a listener for a particular message routing ID. 565821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) void RemoveRoute(int32 routing_id); 575821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 585821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) private: 595821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // A list of all listeners with assigned routing IDs. 605821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) IDMap<IPC::Listener> routes_; 615821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 625821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) DISALLOW_COPY_AND_ASSIGN(MessageRouter); 635821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)}; 645821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 655821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} // namespace content 665821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 675821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#endif // CONTENT_COMMON_MESSAGE_ROUTER_H_ 68