Add TransportSession interface to prepare for WebRTC-based transport.

remoting/protocol/ice_transport_session.cc

Index: remoting/protocol/ice_transport_session.cc
diff --git a/remoting/protocol/ice_transport_session.cc b/remoting/protocol/ice_transport_session.cc
new file mode 100644
index 0000000000000000000000000000000000000000..f87e65534b5dd1671f34daeb981d606ed98c09ec
--- /dev/null
+++ b/remoting/protocol/ice_transport_session.cc
@@ -0,0 +1,193 @@
+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "remoting/protocol/ice_transport_session.h"
+
+#include "remoting/protocol/channel_authenticator.h"
+#include "remoting/protocol/channel_multiplexer.h"
+#include "remoting/protocol/libjingle_transport_factory.h"
+#include "remoting/protocol/pseudotcp_channel_factory.h"
+#include "remoting/protocol/secure_channel_factory.h"
+#include "remoting/protocol/stream_channel_factory.h"
+
+namespace remoting {
+namespace protocol {
+
+// Delay after candidate creation before sending transport-info message to
+// accumulate multiple candidates. This is an optimization to reduce number of
+// transport-info messages.
+const int kTransportInfoSendDelayMs = 20;
+
+// Name of the multiplexed channel.
+static const char kMuxChannelName[] = "mux";
+
+IceTransportSession::IceTransportSession(
+    LibjingleTransportFactory* libjingle_transport_factory)
+    : libjingle_transport_factory_(libjingle_transport_factory) {}
+
+IceTransportSession::~IceTransportSession() {
+  channel_multiplexer_.reset();
+  DCHECK(channels_.empty());
+}
+
+void IceTransportSession::Start(TransportSession::EventHandler* event_handler,
+                                Authenticator* authenticator) {
+  event_handler_ = event_handler;
+  pseudotcp_channel_factory_.reset(new PseudoTcpChannelFactory(this));
+  secure_channel_factory_.reset(new SecureChannelFactory(
+      pseudotcp_channel_factory_.get(), authenticator));
+}
+
+bool IceTransportSession::ProcessTransportInfo(
+    buzz::XmlElement* transport_info_xml) {
+  IceTransportInfo transport_info;
+  if (!transport_info.ParseXml(transport_info_xml))
+    return false;
+
+  for (auto it = transport_info.ice_credentials.begin();
+       it != transport_info.ice_credentials.end(); ++it) {
+    ChannelsMap::iterator channel = channels_.find(it->channel);
+    if (channel != channels_.end()) {
+      channel->second->SetRemoteCredentials(it->ufrag, it->password);
+    } else {
+      // Transport info was received before the channel was created.
+      // This could happen due to messages being reordered on the wire.
+      pending_remote_ice_credentials_.push_back(*it);
+    }
+  }
+
+  for (auto it = transport_info.candidates.begin();
+       it != transport_info.candidates.end(); ++it) {
+    ChannelsMap::iterator channel = channels_.find(it->name);
+    if (channel != channels_.end()) {
+      channel->second->AddRemoteCandidate(it->candidate);
+    } else {
+      // Transport info was received before the channel was created.
+      // This could happen due to messages being reordered on the wire.
+      pending_remote_candidates_.push_back(*it);
+    }
+  }
+
+  return true;
+}
+
+DatagramChannelFactory* IceTransportSession::GetDatagramChannelFactory() {
+  return this;
+}
+
+StreamChannelFactory* IceTransportSession::GetStreamChannelFactory() {
+  return secure_channel_factory_.get();
+}
+
+StreamChannelFactory* IceTransportSession::GetMultiplexedChannelFactory() {
+  if (!channel_multiplexer_.get()) {
+    channel_multiplexer_.reset(
+        new ChannelMultiplexer(GetStreamChannelFactory(), kMuxChannelName));
+  }
+  return channel_multiplexer_.get();
+}
+
+void IceTransportSession::CreateChannel(
+    const std::string& name,
+    const ChannelCreatedCallback& callback) {
+  DCHECK(!channels_[name]);
+
+  scoped_ptr<Transport> channel =
+      libjingle_transport_factory_->CreateTransport();
+  channel->Connect(name, this, callback);
+  AddPendingRemoteTransportInfo(channel.get());
+  channels_[name] = channel.release();
+}
+
+void IceTransportSession::CancelChannelCreation(const std::string& name) {
+  ChannelsMap::iterator it = channels_.find(name);
+  if (it != channels_.end()) {
+    DCHECK(!it->second->is_connected());
+    delete it->second;
+    DCHECK(channels_.find(name) == channels_.end());
+  }
+}
+
+void IceTransportSession::AddPendingRemoteTransportInfo(Transport* channel) {
+  std::list<IceTransportInfo::IceCredentials>::iterator credentials =
+      pending_remote_ice_credentials_.begin();
+  while (credentials != pending_remote_ice_credentials_.end()) {
+    if (credentials->channel == channel->name()) {
+      channel->SetRemoteCredentials(credentials->ufrag, credentials->password);
+      credentials = pending_remote_ice_credentials_.erase(credentials);
+    } else {
+      ++credentials;
+    }
+  }
+
+  std::list<IceTransportInfo::NamedCandidate>::iterator candidate =
+      pending_remote_candidates_.begin();
+  while (candidate != pending_remote_candidates_.end()) {
+    if (candidate->name == channel->name()) {
+      channel->AddRemoteCandidate(candidate->candidate);
+      candidate = pending_remote_candidates_.erase(candidate);
+    } else {
+      ++candidate;
+    }
+  }
+}
+
+void IceTransportSession::OnTransportIceCredentials(
+    Transport* transport,
+    const std::string& ufrag,
+    const std::string& password) {
+  EnsurePendingTransportInfoMessage();
+  pending_transport_info_message_->ice_credentials.push_back(
+      IceTransportInfo::IceCredentials(transport->name(), ufrag, password));
+}
+
+void IceTransportSession::OnTransportCandidate(
+    Transport* transport,
+    const cricket::Candidate& candidate) {
+  EnsurePendingTransportInfoMessage();
+  pending_transport_info_message_->candidates.push_back(
+      IceTransportInfo::NamedCandidate(transport->name(), candidate));
+}
+
+void IceTransportSession::OnTransportRouteChange(Transport* transport,
+                                                 const TransportRoute& route) {
+  if (event_handler_)
+    event_handler_->OnTransportRouteChange(transport->name(), route);
+}
+
+void IceTransportSession::OnTransportFailed(Transport* transport) {
+  event_handler_->OnTransportError(CHANNEL_CONNECTION_ERROR);
+}
+
+void IceTransportSession::OnTransportDeleted(Transport* transport) {
+  ChannelsMap::iterator it = channels_.find(transport->name());
+  DCHECK_EQ(it->second, transport);
+  channels_.erase(it);
+}
+
+void IceTransportSession::EnsurePendingTransportInfoMessage() {
+  // |transport_info_timer_| must be running iff
+  // |pending_transport_info_message_| exists.
+  DCHECK_EQ(pending_transport_info_message_ != nullptr,
+            transport_info_timer_.IsRunning());
+
+  if (!pending_transport_info_message_) {
+    pending_transport_info_message_.reset(new IceTransportInfo());
+    // Delay sending the new candidates in case we get more candidates
+    // that we can send in one message.
+    transport_info_timer_.Start(
+        FROM_HERE, base::TimeDelta::FromMilliseconds(kTransportInfoSendDelayMs),
+        this, &IceTransportSession::SendTransportInfo);
+  }
+}
+
+void IceTransportSession::SendTransportInfo() {
+  DCHECK(pending_transport_info_message_);
+  event_handler_->OnOutgoingTransportInfo(
+      pending_transport_info_message_->ToXml());
+  pending_transport_info_message_.reset();
+}
+
+}  // namespace protocol
+}  // namespace remoting