blob: dfac4578e9c4860a623055b7095c85ab27e6829a [file] [log] [blame]
/* Copyright 2018 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.
*/
// This is EXPERIMENTAL interface for media and datagram transports.
#ifndef API_TRANSPORT_DATAGRAM_TRANSPORT_INTERFACE_H_
#define API_TRANSPORT_DATAGRAM_TRANSPORT_INTERFACE_H_
#include <memory>
#include <string>
#include <utility>
#include "absl/types/optional.h"
#include "api/array_view.h"
#include "api/rtc_error.h"
#include "api/transport/congestion_control_interface.h"
#include "api/transport/data_channel_transport_interface.h"
#include "api/units/data_rate.h"
#include "api/units/timestamp.h"
namespace rtc {
class PacketTransportInternal;
} // namespace rtc
namespace webrtc {
class MediaTransportStateCallback;
typedef int64_t DatagramId;
struct DatagramAck {
// |datagram_id| is same as passed in
// DatagramTransportInterface::SendDatagram.
DatagramId datagram_id;
// The timestamp at which the remote peer received the identified datagram,
// according to that peer's clock.
Timestamp receive_timestamp = Timestamp::MinusInfinity();
};
// All sink methods are called on network thread.
class DatagramSinkInterface {
public:
virtual ~DatagramSinkInterface() {}
// Called when new packet is received.
virtual void OnDatagramReceived(rtc::ArrayView<const uint8_t> data) = 0;
// Called when datagram is actually sent (datragram can be delayed due
// to congestion control or fusing). |datagram_id| is same as passed in
// DatagramTransportInterface::SendDatagram.
virtual void OnDatagramSent(DatagramId datagram_id) = 0;
// Called when datagram is ACKed.
virtual void OnDatagramAcked(const DatagramAck& datagram_ack) = 0;
// Called when a datagram is lost.
virtual void OnDatagramLost(DatagramId datagram_id) = 0;
};
// Datagram transport allows to send and receive unreliable packets (datagrams)
// and receive feedback from congestion control (via
// CongestionControlInterface). The idea is to send RTP packets as datagrams and
// have underlying implementation of datagram transport to use QUIC datagram
// protocol.
class DatagramTransportInterface : public DataChannelTransportInterface {
public:
virtual ~DatagramTransportInterface() = default;
// Connect the datagram transport to the ICE transport.
// The implementation must be able to ignore incoming packets that don't
// belong to it.
virtual void Connect(rtc::PacketTransportInternal* packet_transport) = 0;
// Returns congestion control feedback interface or nullptr if datagram
// transport does not implement congestion control.
//
// Note that right now datagram transport is used without congestion control,
// but we plan to use it in the future.
virtual CongestionControlInterface* congestion_control() = 0;
// Sets a state observer callback. Before datagram transport is destroyed, the
// callback must be unregistered by setting it to nullptr.
// A newly registered callback will be called with the current state.
// Datagram transport does not invoke this callback concurrently.
virtual void SetTransportStateCallback(
MediaTransportStateCallback* callback) = 0;
// Start asynchronous send of datagram. The status returned by this method
// only pertains to the synchronous operations (e.g. serialization /
// packetization), not to the asynchronous operation.
//
// Datagrams larger than GetLargestDatagramSize() will fail and return error.
//
// Datagrams are sent in FIFO order.
//
// |datagram_id| is only used in ACK/LOST notifications in
// DatagramSinkInterface and does not need to be unique.
virtual RTCError SendDatagram(rtc::ArrayView<const uint8_t> data,
DatagramId datagram_id) = 0;
// Returns maximum size of datagram message, does not change.
// TODO(sukhanov): Because value may be undefined before connection setup
// is complete, consider returning error when called before connection is
// established. Currently returns hardcoded const, because integration
// prototype may call before connection is established.
virtual size_t GetLargestDatagramSize() const = 0;
// Sets packet sink. Sink must be unset by calling
// SetDataTransportSink(nullptr) before the data transport is destroyed or
// before new sink is set.
virtual void SetDatagramSink(DatagramSinkInterface* sink) = 0;
// Retrieves transport parameters for this datagram transport. May be called
// on either client- or server-perspective transports.
//
// For servers, the parameters represent what kind of connections and data the
// server is prepared to accept. This is generally a superset of acceptable
// parameters.
//
// For clients, the parameters echo the server configuration used to create
// the client, possibly removing any fields or parameters which the client
// does not understand.
virtual std::string GetTransportParameters() const = 0;
};
} // namespace webrtc
#endif // API_TRANSPORT_DATAGRAM_TRANSPORT_INTERFACE_H_