Add QuicDataChannel and QuicDataTransport classes

webrtc/api/quicdatatransport.h

+/*
+ *  Copyright 2016 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.
+ */
+
+#ifndef WEBRTC_API_QUICDATATRANSPORT_H_
+#define WEBRTC_API_QUICDATATRANSPORT_H_
+
+#include <string>
+#include <unordered_map>
+
+#include "webrtc/api/datachannelinterface.h"
+#include "webrtc/api/quicdatachannel.h"
+#include "webrtc/base/scoped_ref_ptr.h"
+#include "webrtc/base/sigslot.h"
+#include "webrtc/base/thread.h"
+
+namespace cricket {
+class QuicTransportChannel;
+class ReliableQuicStream;
+}  // namepsace cricket
+
+namespace webrtc {
+
+// QuicDataTransport creates QuicDataChannels. It handles QUIC stream demuxing
+// by prepending the data channel ID and message ID to outgoing messages, and
+// distributes incoming QUIC streams from the QuicTransportChannel.
+//
+// QuicDataTransport reads the data channel ID from the incoming QUIC stream,
+// then looks it up in a map of ID => QuicDataChannel. If the data channel
+// exists, it sends the stream to the QuicDataChannel.
+class QuicDataTransport : public QuicMessageDispatcher,
+                          public sigslot::has_slots<> {
+ public:
+  QuicDataTransport();
+  ~QuicDataTransport() override;
+
+  // Sets the QUIC transport channel for the QuicDataChannels and the
+  // QuicDataTransport. The QUIC transport channel must not already be set.
+  void SetTransportChannel(
+      cricket::QuicTransportChannel* quic_transport_channel);
+  // Creates a QuicDataChannel that uses this QuicDataTransport.
+  rtc::scoped_refptr<DataChannelInterface> CreateDataChannel(
+      rtc::Thread* signaling_thread,
+      rtc::Thread* worker_thread,
+      const std::string& label,
+      const DataChannelInit* config);
+  // Removes a QuicDataChannel from the QuicDataTransport's data channel map.
+  void DestroyDataChannel(int id);
+  // True if the QuicDataTransport has a data channel with the given ID.
+  bool HasDataChannel(int id) const;
+  // True if the QuicDataTransport has data channels.
+  bool HasDataChannels() const;
+
+  // QuicMessageDispatcher override.
+  void EncodeHeader(int data_channel_id,
+                    uint64_t message_id,
+                    rtc::CopyOnWriteBuffer* payload) const override;
+
+ private:
+  // Called by the QuicTransportChannel when a ReliableQuicStream is created to
+  // receive incoming data.
+  void OnIncomingStream(cricket::ReliableQuicStream* stream);
+  // Called by the ReliableQuicStream when the first QUIC stream frame is
+  // received for incoming data.
+  void OnDataReceived(net::QuicStreamId stream_id,
+                      const char* data,
+                      size_t len);
+
+  // Map of data channel ID => QUIC data channel values.
+  std::unordered_map<int, rtc::scoped_refptr<QuicDataChannel>>
+      data_channel_by_id_;
+  // Map of QUIC stream ID => ReliableQuicStream* values.
+  std::unordered_map<net::QuicStreamId, cricket::ReliableQuicStream*>
+      quic_stream_by_id_;
+  // QuicTransportChannel for sending/receiving data.
+  cricket::QuicTransportChannel* quic_transport_channel_ = nullptr;
+};
+
+}  // namespace webrtc
+
+#endif  // WEBRTC_API_QUICDATATRANSPORT_H_