text: /*
   *  Copyright (c) 2019 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.
   */
  
  #include "test/network/emulated_network_manager.h"
  
  #include <memory>
  #include <utility>
  
  #include "absl/memory/memory.h"
  #include "test/network/fake_network_socket_server.h"
  
  namespace webrtc {
  namespace test {
  
  EmulatedNetworkManager::EmulatedNetworkManager(
      TimeController* time_controller,
      TaskQueueForTest* task_queue,
      EndpointsContainer* endpoints_container)
      : task_queue_(task_queue),
        endpoints_container_(endpoints_container),
        network_thread_(time_controller->CreateThread(
            "net_thread",
            std::make_unique<FakeNetworkSocketServer>(endpoints_container))),
        sent_first_update_(false),
        start_count_(0) {}
  
  void EmulatedNetworkManager::EnableEndpoint(EmulatedEndpointImpl* endpoint) {
    RTC_CHECK(endpoints_container_->HasEndpoint(endpoint))
        << "No such interface: " << endpoint->GetPeerLocalAddress().ToString();
    network_thread_->PostTask(RTC_FROM_HERE, [this, endpoint]() {
      endpoint->Enable();
      UpdateNetworksOnce();
    });
  }
  
  void EmulatedNetworkManager::DisableEndpoint(EmulatedEndpointImpl* endpoint) {
    RTC_CHECK(endpoints_container_->HasEndpoint(endpoint))
        << "No such interface: " << endpoint->GetPeerLocalAddress().ToString();
    network_thread_->PostTask(RTC_FROM_HERE, [this, endpoint]() {
      endpoint->Disable();
      UpdateNetworksOnce();
    });
  }
  
  // Network manager interface. All these methods are supposed to be called from
  // the same thread.
  void EmulatedNetworkManager::StartUpdating() {
    RTC_DCHECK_RUN_ON(network_thread_.get());
  
    if (start_count_) {
      // If network interfaces are already discovered and signal is sent,
      // we should trigger network signal immediately for the new clients
      // to start allocating ports.
      if (sent_first_update_)
        network_thread_->PostTask(RTC_FROM_HERE,
                                  [this]() { MaybeSignalNetworksChanged(); });
    } else {
      network_thread_->PostTask(RTC_FROM_HERE,
                                [this]() { UpdateNetworksOnce(); });
    }
    ++start_count_;
  }
  
  void EmulatedNetworkManager::StopUpdating() {
    RTC_DCHECK_RUN_ON(network_thread_.get());
    if (!start_count_)
      return;
  
    --start_count_;
    if (!start_count_) {
      sent_first_update_ = false;
    }
  }
  
  void EmulatedNetworkManager::GetStats(
      std::function<void(EmulatedNetworkStats)> stats_callback) const {
    task_queue_->PostTask([stats_callback, this]() {
      stats_callback(endpoints_container_->GetStats());
    });
  }
  
  void EmulatedNetworkManager::UpdateNetworksOnce() {
    RTC_DCHECK_RUN_ON(network_thread_.get());
  
    std::vector<rtc::Network*> networks;
    for (std::unique_ptr<rtc::Network>& net :
         endpoints_container_->GetEnabledNetworks()) {
      net->set_default_local_address_provider(this);
      networks.push_back(net.release());
    }
  
    bool changed;
    MergeNetworkList(networks, &changed);
    if (changed || !sent_first_update_) {
      MaybeSignalNetworksChanged();
      sent_first_update_ = true;
    }
  }
  
  void EmulatedNetworkManager::MaybeSignalNetworksChanged() {
    RTC_DCHECK_RUN_ON(network_thread_.get());
    // If manager is stopped we don't need to signal anything.
    if (start_count_ == 0) {
      return;
    }
    SignalNetworksChanged();
  }
  
  }  // namespace test
  }  // namespace webrtc
  