Ping backup connection at a slower rate

webrtc/p2p/base/p2ptransportchannel.h

 /*
  *  Copyright 2004 The WebRTC Project Authors. All rights reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 162 matching lines @@
   // A transport channel is weak if the current best connection is either
   // not receiving or not writable, or if there is no best connection at all.
   bool weak() const;
   void UpdateConnectionStates();
   void RequestSort();
   void SortConnections();
   void SwitchBestConnectionTo(Connection* conn);
   void UpdateChannelState();
   void HandleAllTimedOut();
   void MaybeStopPortAllocatorSessions();
+  TransportChannelState ComputeState() const;
 
   Connection* GetBestConnectionOnNetwork(rtc::Network* network) const;
   bool CreateConnections(const Candidate& remote_candidate,
                          PortInterface* origin_port);
   bool CreateConnection(PortInterface* port,
                         const Candidate& remote_candidate,
                         PortInterface* origin_port);
   bool FindConnection(cricket::Connection* connection) const;
 
   uint32_t GetRemoteCandidateGeneration(const Candidate& candidate);
   bool IsDuplicateRemoteCandidate(const Candidate& candidate);
   void RememberRemoteCandidate(const Candidate& remote_candidate,
                                PortInterface* origin_port);
-  bool IsPingable(Connection* conn);
+  bool IsPingable(Connection* conn, uint32_t now);
   void PingConnection(Connection* conn);
   void AddAllocatorSession(PortAllocatorSession* session);
   void AddConnection(Connection* connection);
 
   void OnPortReady(PortAllocatorSession *session, PortInterface* port);
   void OnCandidatesReady(PortAllocatorSession *session,
                          const std::vector<Candidate>& candidates);
   void OnCandidatesAllocationDone(PortAllocatorSession* session);
   void OnUnknownAddress(PortInterface* port,
                         const rtc::SocketAddress& addr,
@@ skipping 12 matching lines @@
   void OnConnectionDestroyed(Connection *connection);
 
   void OnNominated(Connection* conn);
 
   void OnMessage(rtc::Message* pmsg) override;
   void OnSort();
   void OnCheckAndPing();
 
   void PruneConnections();
   Connection* best_nominated_connection() const;
+  bool IsBackupConnection(Connection* conn) const;
 
   P2PTransport* transport_;
   PortAllocator* allocator_;
   rtc::Thread* worker_thread_;
   bool incoming_only_;
   int error_;
   std::vector<PortAllocatorSession*> allocator_sessions_;
   std::vector<PortInterface *> ports_;
   std::vector<Connection *> connections_;
   Connection* best_connection_;
@@ skipping 10 matching lines @@
   std::string remote_ice_ufrag_;
   std::string remote_ice_pwd_;
   IceMode remote_ice_mode_;
   IceRole ice_role_;
   uint64_t tiebreaker_;
   uint32_t remote_candidate_generation_;
   IceGatheringState gathering_state_;
 
   int check_receiving_delay_;
   int receiving_timeout_;
+  int backup_connection_ping_interval_;
   uint32_t last_ping_sent_ms_ = 0;
   bool gather_continually_ = false;
   int weak_ping_delay_ = WEAK_PING_DELAY;
+  TransportChannelState state_ = TransportChannelState::STATE_INIT;
 
   RTC_DISALLOW_COPY_AND_ASSIGN(P2PTransportChannel);
 };
 
 }  // namespace cricket
 
 #endif  // WEBRTC_P2P_BASE_P2PTRANSPORTCHANNEL_H_