1 // Copyright (c) 2011 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef NET_WEBSOCKETS_WEBSOCKET_THROTTLE_H_ 6 #define NET_WEBSOCKETS_WEBSOCKET_THROTTLE_H_ 7 8 #include <deque> 9 #include <map> 10 #include <set> 11 #include <string> 12 13 #include "net/base/ip_endpoint.h" 14 #include "net/base/net_export.h" 15 16 template <typename T> struct DefaultSingletonTraits; 17 18 namespace net { 19 20 class SocketStream; 21 class WebSocketJob; 22 23 // SocketStreamThrottle for WebSocket protocol. 24 // Implements the client-side requirements in the spec. 25 // http://tools.ietf.org/html/draft-hixie-thewebsocketprotocol 26 // 4.1 Handshake 27 // 1. If the user agent already has a Web Socket connection to the 28 // remote host (IP address) identified by /host/, even if known by 29 // another name, wait until that connection has been established or 30 // for that connection to have failed. 31 class NET_EXPORT_PRIVATE WebSocketThrottle { 32 public: 33 // Returns the singleton instance. 34 static WebSocketThrottle* GetInstance(); 35 36 // Puts |job| in |queue_| and queues for the destination addresses 37 // of |job|. 38 // If other job is using the same destination address, set |job| waiting. 39 // 40 // Returns true if successful. If the number of pending jobs will exceed 41 // the limit, does nothing and returns false. 42 bool PutInQueue(WebSocketJob* job); 43 44 // Removes |job| from |queue_| and queues for the destination addresses 45 // of |job|, and then wakes up jobs that can now resume establishing a 46 // connection. 47 void RemoveFromQueue(WebSocketJob* job); 48 49 private: 50 typedef std::deque<WebSocketJob*> ConnectingQueue; 51 typedef std::map<IPEndPoint, ConnectingQueue> ConnectingAddressMap; 52 53 WebSocketThrottle(); 54 ~WebSocketThrottle(); 55 friend struct DefaultSingletonTraits<WebSocketThrottle>; 56 57 // Examines if any of the given jobs can resume establishing a connection. If 58 // for all per-address queues for each resolved addresses 59 // (job->address_list()) of a job, the job is at the front of the queues, the 60 // job can resume establishing a connection, so wakes up the job. 61 void WakeupSocketIfNecessary( 62 const std::set<WebSocketJob*>& wakeup_candidates); 63 64 // Key: string of host's address. Value: queue of sockets for the address. 65 ConnectingAddressMap addr_map_; 66 67 // Queue of sockets for websockets in opening state. 68 ConnectingQueue queue_; 69 70 DISALLOW_COPY_AND_ASSIGN(WebSocketThrottle); 71 }; 72 73 } // namespace net 74 75 #endif // NET_WEBSOCKETS_WEBSOCKET_THROTTLE_H_ 76
