1 /* 2 * Copyright 2011 The WebRTC Project Authors. All rights reserved. 3 * 4 * Use of this source code is governed by a BSD-style license 5 * that can be found in the LICENSE file in the root of the source 6 * tree. An additional intellectual property rights grant can be found 7 * in the file PATENTS. All contributing project authors may 8 * be found in the AUTHORS file in the root of the source tree. 9 */ 10 11 #ifndef WEBRTC_LIBJINGLE_XMPP_PINGTASK_H_ 12 #define WEBRTC_LIBJINGLE_XMPP_PINGTASK_H_ 13 14 #include "webrtc/libjingle/xmpp/xmpptask.h" 15 #include "webrtc/base/messagehandler.h" 16 #include "webrtc/base/messagequeue.h" 17 18 namespace buzz { 19 20 // Task to periodically send pings to the server to ensure that the network 21 // connection is valid, implementing XEP-0199. 22 // 23 // This is especially useful on cellular networks because: 24 // 1. It keeps the connections alive through the cellular network's NATs or 25 // proxies. 26 // 2. It detects when the server has crashed or any other case in which the 27 // connection has broken without a fin or reset packet being sent to us. 28 class PingTask : public buzz::XmppTask, private rtc::MessageHandler { 29 public: 30 PingTask(buzz::XmppTaskParentInterface* parent, 31 rtc::MessageQueue* message_queue, 32 uint32_t ping_period_millis, 33 uint32_t ping_timeout_millis); 34 35 virtual bool HandleStanza(const buzz::XmlElement* stanza); 36 virtual int ProcessStart(); 37 38 // Raised if there is no response to a ping within ping_timeout_millis. 39 // The task is automatically aborted after a timeout. 40 sigslot::signal0<> SignalTimeout; 41 42 private: 43 // Implementation of MessageHandler. 44 virtual void OnMessage(rtc::Message* msg); 45 46 rtc::MessageQueue* message_queue_; 47 uint32_t ping_period_millis_; 48 uint32_t ping_timeout_millis_; 49 uint32_t next_ping_time_; 50 uint32_t ping_response_deadline_; // 0 if the response has been received 51 }; 52 53 } // namespace buzz 54 55 #endif // WEBRTC_LIBJINGLE_XMPP_PINGTASK_H_ 56