Add QuicDataChannel and QuicDataTransport classes

webrtc/api/quicdatatransport.cc

+/*
+ *  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.
+ */
+
+#include "webrtc/api/quicdatatransport.h"
+
+#include "webrtc/base/bytebuffer.h"
+#include "webrtc/base/logging.h"
+#include "webrtc/p2p/quic/quictransportchannel.h"
+#include "webrtc/p2p/quic/reliablequicstream.h"
+
+namespace webrtc {
+
+QuicDataTransport::QuicDataTransport() {}
+
+QuicDataTransport::~QuicDataTransport() {}
+
+void QuicDataTransport::SetTransportChannel(
+    cricket::QuicTransportChannel* channel) {
+  RTC_DCHECK(channel != nullptr);
+  RTC_DCHECK(quic_transport_channel_ == nullptr);
+
+  LOG(LS_INFO) << "Setting QuicTransportChannel for QuicDataTransport";
+  quic_transport_channel_ = channel;
+  quic_transport_channel_->SignalIncomingStream.connect(
+      this, &QuicDataTransport::OnIncomingStream);
+
+  for (const auto& kv : data_channel_by_id_) {
+    rtc::scoped_refptr<QuicDataChannel> data_channel = kv.second;
+    data_channel->SetTransportChannel(quic_transport_channel_);
+  }
+}
+
+rtc::scoped_refptr<DataChannelInterface> QuicDataTransport::CreateDataChannel(
+    rtc::Thread* signaling_thread,
+    rtc::Thread* worker_thread,
+    const std::string& label,
+    const DataChannelInit* config) {
+  RTC_DCHECK(config != nullptr);
+  if (data_channel_by_id_.find(config->id) != data_channel_by_id_.end()) {
+    LOG(LS_ERROR) << "QUIC data channel already exists with id " << config->id;
+    return nullptr;
+  }
+  rtc::scoped_refptr<QuicDataChannel> data_channel(new QuicDataChannel(
+      signaling_thread, worker_thread, label, *config, *this));
+  if (quic_transport_channel_) {
+    data_channel->SetTransportChannel(quic_transport_channel_);
+  }
+
+  data_channel_by_id_[data_channel->id()] = data_channel;
+  return data_channel;
+}
+
+void QuicDataTransport::DestroyDataChannel(int id) {
+  data_channel_by_id_.erase(id);
+}
+
+bool QuicDataTransport::HasDataChannel(int id) const {
+  return data_channel_by_id_.find(id) != data_channel_by_id_.end();
+}
+
+bool QuicDataTransport::HasDataChannels() const {
+  return !data_channel_by_id_.empty();
+}
+
+// Called when a QUIC stream is created for incoming data.
+void QuicDataTransport::OnIncomingStream(cricket::ReliableQuicStream* stream) {
+  RTC_DCHECK(stream != nullptr);
+  quic_stream_by_id_[stream->id()] = stream;
+  stream->SignalDataReceived.connect(this, &QuicDataTransport::OnDataReceived);
+}
+
+// Called when the first QUIC stream frame is received for incoming data.
+void QuicDataTransport::OnDataReceived(net::QuicStreamId id,
+                                       const char* data,
+                                       size_t len) {
+  RTC_DCHECK(quic_stream_by_id_.find(id) != quic_stream_by_id_.end());
+  cricket::ReliableQuicStream* stream = quic_stream_by_id_[id];
+  stream->SignalDataReceived.disconnect(this);
+  quic_stream_by_id_.erase(id);
+  // Read data channel id
+  rtc::ByteBufferReader byte_buffer(data, len, rtc::ByteBuffer::ORDER_HOST);
+  uint64_t data_channel_id;
+  if (!byte_buffer.ReadUVarint(&data_channel_id)) {
+    LOG(LS_ERROR) << "Could not read the data channel ID for QUIC stream "
+                  << id;
+    return;
+  }
+  // Retrieve the data channel which will handle the message.
+  const auto& kv = data_channel_by_id_.find(data_channel_id);
+  if (kv == data_channel_by_id_.end()) {
+    // TODO(mikescarlett): Implement OPEN message to create a new
+    // QuicDataChannel when messages are received for a nonexistent ID.
+    LOG(LS_ERROR) << "Data was received for QUIC data channel "
+                  << data_channel_id
+                  << " but it is not registered to the QuicDataTransport.";
+    return;
+  }
+  QuicDataChannel* data_channel = kv->second;
+  uint64_t message_id;
+  if (!byte_buffer.ReadUVarint(&message_id)) {
+    LOG(LS_ERROR) << "Could not read message ID for QUIC stream " << id
+                  << " destined for data channel " << data_channel_id;
+    return;
+  }
+  QuicMessageDispatcher::Dispatch(data_channel, message_id, byte_buffer.Data(),
+                                  byte_buffer.Length(), stream);
+}
+
+void QuicDataTransport::EncodeHeader(int data_channel_id,
+                                     uint64_t message_id,
+                                     rtc::CopyOnWriteBuffer* header) const {
+  RTC_DCHECK(header != nullptr);
+  // 64-bit varints require at most 10 bytes (7*10 == 70), and 32-bit varints
+  // require at most 5 bytes (7*5 == 35).
+  size_t max_length = 15;
+  rtc::ByteBufferWriter byte_buffer(nullptr, max_length,
+                                    rtc::ByteBuffer::ByteOrder::ORDER_HOST);
+  byte_buffer.WriteUVarint(data_channel_id);
+  byte_buffer.WriteUVarint(message_id);
+  header->SetData(byte_buffer.Data(), byte_buffer.Length());
+}
+
+}  // namespace webrtc