1 /* 2 * Copyright 2018 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 P2P_BASE_REGATHERING_CONTROLLER_H_ 12 #define P2P_BASE_REGATHERING_CONTROLLER_H_ 13 14 #include "p2p/base/ice_transport_internal.h" 15 #include "p2p/base/port_allocator.h" 16 #include "rtc_base/async_invoker.h" 17 #include "rtc_base/thread.h" 18 19 namespace webrtc { 20 21 // Controls regathering of candidates for the ICE transport passed into it, 22 // reacting to signals like SignalWritableState, SignalNetworkRouteChange, etc., 23 // using methods like GetStats to get additional information, and calling 24 // methods like RegatherOnFailedNetworks on the PortAllocatorSession when 25 // regathering is desired. 26 // 27 // "Regathering" is defined as gathering additional candidates within a single 28 // ICE generation (or in other words, PortAllocatorSession), and is possible 29 // when "continual gathering" is enabled. This may allow connectivity to be 30 // maintained and/or restored without a full ICE restart. 31 // 32 // Regathering will only begin after PortAllocationSession is set via 33 // set_allocator_session. This should be called any time the "active" 34 // PortAllocatorSession is changed (in other words, when an ICE restart occurs), 35 // so that candidates are gathered for the "current" ICE generation. 36 // 37 // All methods of BasicRegatheringController should be called on the same 38 // thread as the one passed to the constructor, and this thread should be the 39 // same one where PortAllocatorSession runs, which is also identical to the 40 // network thread of the ICE transport, as given by 41 // P2PTransportChannel::thread(). 42 class BasicRegatheringController : public sigslot::has_slots<> { 43 public: 44 struct Config { 45 int regather_on_failed_networks_interval = 46 cricket::REGATHER_ON_FAILED_NETWORKS_INTERVAL; 47 }; 48 49 BasicRegatheringController() = delete; 50 BasicRegatheringController(const Config& config, 51 cricket::IceTransportInternal* ice_transport, 52 rtc::Thread* thread); 53 ~BasicRegatheringController() override; 54 // TODO(qingsi): Remove this method after implementing a new signal in 55 // P2PTransportChannel and reacting to that signal for the initial schedules 56 // of regathering. 57 void Start(); set_allocator_session(cricket::PortAllocatorSession * allocator_session)58 void set_allocator_session(cricket::PortAllocatorSession* allocator_session) { 59 allocator_session_ = allocator_session; 60 } 61 // Setting a different config of the regathering interval range on all 62 // networks cancels and reschedules the recurring schedules, if any, of 63 // regathering on all networks. The same applies to the change of the 64 // regathering interval on the failed networks. This rescheduling behavior is 65 // seperately defined for the two config parameters. 66 void SetConfig(const Config& config); 67 68 private: 69 // TODO(qingsi): Implement the following methods and use methods from the ICE 70 // transport like GetStats to get additional information for the decision 71 // making in regathering. OnIceTransportStateChanged(cricket::IceTransportInternal *)72 void OnIceTransportStateChanged(cricket::IceTransportInternal*) {} OnIceTransportWritableState(rtc::PacketTransportInternal *)73 void OnIceTransportWritableState(rtc::PacketTransportInternal*) {} OnIceTransportReceivingState(rtc::PacketTransportInternal *)74 void OnIceTransportReceivingState(rtc::PacketTransportInternal*) {} OnIceTransportNetworkRouteChanged(absl::optional<rtc::NetworkRoute>)75 void OnIceTransportNetworkRouteChanged(absl::optional<rtc::NetworkRoute>) {} 76 // Schedules delayed and repeated regathering of local candidates on failed 77 // networks, where the delay in milliseconds is given by the config. Each 78 // repetition is separated by the same delay. When scheduled, all previous 79 // schedules are canceled. 80 void ScheduleRecurringRegatheringOnFailedNetworks(); 81 // Cancels regathering scheduled by ScheduleRecurringRegatheringOnAllNetworks. 82 void CancelScheduledRecurringRegatheringOnAllNetworks(); 83 // Cancels regathering scheduled by 84 // ScheduleRecurringRegatheringOnFailedNetworks. 85 void CancelScheduledRecurringRegatheringOnFailedNetworks(); 86 87 // The following method perform the actual regathering, if the recent port 88 // allocator session has done the initial gathering. 89 void RegatherOnFailedNetworksIfDoneGathering(); 90 91 Config config_; 92 cricket::IceTransportInternal* ice_transport_; 93 cricket::PortAllocatorSession* allocator_session_ = nullptr; 94 bool has_recurring_schedule_on_failed_networks_ = false; 95 rtc::Thread* thread_; 96 rtc::AsyncInvoker invoker_for_failed_networks_; 97 }; 98 99 } // namespace webrtc 100 101 #endif // P2P_BASE_REGATHERING_CONTROLLER_H_ 102