Method get_session

src/stream.cpp:490–548

  static auto broadcast = safe::make_shared<broadcast_ctx_t>(start_broadcast, end_broadcast);

  session_t *control_server_t::get_session(const net::peer_t peer, uint32_t connect_data) {
    {
      // Fast path - look up existing session by peer
      auto lg = _peer_to_session.lock();
      auto it = _peer_to_session->find(peer);
      if (it != _peer_to_session->end()) {
        return it->second;
      }
    }

    // Slow path - process new session
    TUPLE_2D(peer_port, peer_addr, platf::from_sockaddr_ex((sockaddr *) &peer->address.address));
    auto lg = _sessions.lock();
    for (auto pos = std::begin(*_sessions); pos != std::end(*_sessions); ++pos) {
      auto session_p = *pos;

      // Skip sessions that are already established
      if (session_p->control.peer) {
        continue;
      }

      // Identify the connection by the unique connect data if the client supports it.
      // Only fall back to IP address matching for clients without session ID support.
      if (session_p->config.mlFeatureFlags & ML_FF_SESSION_ID_V1) {
        if (session_p->control.connect_data != connect_data) {
          continue;
        } else {
          BOOST_LOG(debug) << "Initialized new control stream session by connect data match [v2]"sv;
        }
      } else {
        if (session_p->control.expected_peer_address != peer_addr) {
          continue;
        } else {
          BOOST_LOG(debug) << "Initialized new control stream session by IP address match [v1]"sv;
        }
      }

      // Once the control stream connection is established, RTSP session state can be torn down
      rtsp_stream::launch_session_clear(session_p->launch_session_id);

      session_p->control.peer = peer;

      // Use the local address from the control connection as the source address
      // for other communications to the client. This is necessary to ensure
      // proper routing on multi-homed hosts.
      auto local_address = platf::from_sockaddr((sockaddr *) &peer->localAddress.address);
      session_p->localAddress = boost::asio::ip::make_address(local_address);

      BOOST_LOG(debug) << "Control local address ["sv << local_address << ']';
      BOOST_LOG(debug) << "Control peer address ["sv << peer_addr << ':' << peer_port << ']';

      // Insert this into the map for O(1) lookups in the future
      auto ptslg = _peer_to_session.lock();
      _peer_to_session->emplace(peer, session_p);
      return session_p;
    }

    return nullptr;