blob: f1a86baa94108a02d3fe0df445b6b81e04be8973 [file] [log] [blame]
* Copyright 2020 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 <stdint.h>
#include <memory>
#include <string>
#include "absl/types/optional.h"
#include "api/data_channel_interface.h"
#include "api/priority.h"
#include "api/rtc_error.h"
#include "api/scoped_refptr.h"
#include "api/transport/data_channel_transport_interface.h"
#include "media/base/media_channel.h"
#include "pc/channel.h"
#include "pc/data_channel_utils.h"
#include "rtc_base/async_invoker.h"
#include "rtc_base/copy_on_write_buffer.h"
#include "rtc_base/third_party/sigslot/sigslot.h"
#include "rtc_base/thread.h"
#include "rtc_base/thread_annotations.h"
namespace webrtc {
class RtpDataChannel;
// TODO(deadbeef): Once RTP data channels go away, get rid of this and have
// DataChannel depend on SctpTransportInternal (pure virtual SctpTransport
// interface) instead.
class RtpDataChannelProviderInterface {
// Sends the data to the transport.
virtual bool SendData(const cricket::SendDataParams& params,
const rtc::CopyOnWriteBuffer& payload,
cricket::SendDataResult* result) = 0;
// Connects to the transport signals.
virtual bool ConnectDataChannel(RtpDataChannel* data_channel) = 0;
// Disconnects from the transport signals.
virtual void DisconnectDataChannel(RtpDataChannel* data_channel) = 0;
// Returns true if the transport channel is ready to send data.
virtual bool ReadyToSendData() const = 0;
virtual ~RtpDataChannelProviderInterface() {}
// RtpDataChannel is an implementation of the DataChannelInterface based on
// libjingle's data engine. It provides an implementation of unreliable data
// channels.
// DataChannel states:
// kConnecting: The channel has been created the transport might not yet be
// ready.
// kOpen: The channel have a local SSRC set by a call to UpdateSendSsrc
// and a remote SSRC set by call to UpdateReceiveSsrc and the transport
// has been writable once.
// kClosing: DataChannelInterface::Close has been called or UpdateReceiveSsrc
// has been called with SSRC==0
// kClosed: Both UpdateReceiveSsrc and UpdateSendSsrc has been called with
// SSRC==0.
class RtpDataChannel : public DataChannelInterface,
public sigslot::has_slots<> {
static rtc::scoped_refptr<RtpDataChannel> Create(
RtpDataChannelProviderInterface* provider,
const std::string& label,
const DataChannelInit& config,
rtc::Thread* signaling_thread);
// Instantiates an API proxy for a DataChannel instance that will be handed
// out to external callers.
static rtc::scoped_refptr<DataChannelInterface> CreateProxy(
rtc::scoped_refptr<RtpDataChannel> channel);
void RegisterObserver(DataChannelObserver* observer) override;
void UnregisterObserver() override;
std::string label() const override { return label_; }
bool reliable() const override { return false; }
bool ordered() const override { return config_.ordered; }
// Backwards compatible accessors
uint16_t maxRetransmitTime() const override {
return config_.maxRetransmitTime ? *config_.maxRetransmitTime
: static_cast<uint16_t>(-1);
uint16_t maxRetransmits() const override {
return config_.maxRetransmits ? *config_.maxRetransmits
: static_cast<uint16_t>(-1);
absl::optional<int> maxPacketLifeTime() const override {
return config_.maxRetransmitTime;
absl::optional<int> maxRetransmitsOpt() const override {
return config_.maxRetransmits;
std::string protocol() const override { return config_.protocol; }
bool negotiated() const override { return config_.negotiated; }
int id() const override { return; }
Priority priority() const override {
return config_.priority ? *config_.priority : Priority::kLow;
virtual int internal_id() const { return internal_id_; }
uint64_t buffered_amount() const override { return 0; }
void Close() override;
DataState state() const override;
RTCError error() const override;
uint32_t messages_sent() const override;
uint64_t bytes_sent() const override;
uint32_t messages_received() const override;
uint64_t bytes_received() const override;
bool Send(const DataBuffer& buffer) override;
// Close immediately, ignoring any queued data or closing procedure.
// This is called when SDP indicates a channel should be removed.
void CloseAbruptlyWithError(RTCError error);
// Called when the channel's ready to use. That can happen when the
// underlying DataMediaChannel becomes ready, or when this channel is a new
// stream on an existing DataMediaChannel, and we've finished negotiation.
void OnChannelReady(bool writable);
// Slots for provider to connect signals to.
void OnDataReceived(const cricket::ReceiveDataParams& params,
const rtc::CopyOnWriteBuffer& payload);
// Called when the transport channel is unusable.
// This method makes sure the DataChannel is disconnected and changes state
// to kClosed.
void OnTransportChannelClosed();
DataChannelStats GetStats() const;
// The remote peer requested that this channel should be closed.
void RemotePeerRequestClose();
// Set the SSRC this channel should use to send data on the
// underlying data engine. |send_ssrc| == 0 means that the channel is no
// longer part of the session negotiation.
void SetSendSsrc(uint32_t send_ssrc);
// Set the SSRC this channel should use to receive data from the
// underlying data engine.
void SetReceiveSsrc(uint32_t receive_ssrc);
// Emitted when state transitions to kOpen.
sigslot::signal1<DataChannelInterface*> SignalOpened;
// Emitted when state transitions to kClosed.
sigslot::signal1<DataChannelInterface*> SignalClosed;
// Reset the allocator for internal ID values for testing, so that
// the internal IDs generated are predictable. Test only.
static void ResetInternalIdAllocatorForTesting(int new_value);
RtpDataChannel(const DataChannelInit& config,
RtpDataChannelProviderInterface* client,
const std::string& label,
rtc::Thread* signaling_thread);
~RtpDataChannel() override;
bool Init();
void UpdateState();
void SetState(DataState state);
void DisconnectFromProvider();
void DeliverQueuedReceivedData();
bool SendDataMessage(const DataBuffer& buffer);
rtc::Thread* const signaling_thread_;
const int internal_id_;
const std::string label_;
const DataChannelInit config_;
DataChannelObserver* observer_ RTC_GUARDED_BY(signaling_thread_) = nullptr;
DataState state_ RTC_GUARDED_BY(signaling_thread_) = kConnecting;
RTCError error_ RTC_GUARDED_BY(signaling_thread_);
uint32_t messages_sent_ RTC_GUARDED_BY(signaling_thread_) = 0;
uint64_t bytes_sent_ RTC_GUARDED_BY(signaling_thread_) = 0;
uint32_t messages_received_ RTC_GUARDED_BY(signaling_thread_) = 0;
uint64_t bytes_received_ RTC_GUARDED_BY(signaling_thread_) = 0;
RtpDataChannelProviderInterface* const provider_;
bool connected_to_provider_ RTC_GUARDED_BY(signaling_thread_) = false;
bool send_ssrc_set_ RTC_GUARDED_BY(signaling_thread_) = false;
bool receive_ssrc_set_ RTC_GUARDED_BY(signaling_thread_) = false;
bool writable_ RTC_GUARDED_BY(signaling_thread_) = false;
uint32_t send_ssrc_ RTC_GUARDED_BY(signaling_thread_) = 0;
uint32_t receive_ssrc_ RTC_GUARDED_BY(signaling_thread_) = 0;
PacketQueue queued_received_data_ RTC_GUARDED_BY(signaling_thread_);
} // namespace webrtc