Remove the dependency of TransportChannel and TransportChannelImpl.

webrtc/p2p/base/dtlstransportchannel.h

Index: webrtc/p2p/base/dtlstransportchannel.h
diff --git a/webrtc/p2p/base/dtlstransportchannel.h b/webrtc/p2p/base/dtlstransportchannel.h
index 5850813fcd6002d36b556572b31e9e1ead0b765d..370dbcb29f3887f73b3d82d148d4f295fa18c784 100644
--- a/webrtc/p2p/base/dtlstransportchannel.h
+++ b/webrtc/p2p/base/dtlstransportchannel.h
@@ -15,12 +15,12 @@
 #include <string>
 #include <vector>
 
-#include "webrtc/p2p/base/transportchannelimpl.h"
 #include "webrtc/base/buffer.h"
 #include "webrtc/base/bufferqueue.h"
 #include "webrtc/base/constructormagic.h"
 #include "webrtc/base/sslstreamadapter.h"
 #include "webrtc/base/stream.h"
+#include "webrtc/p2p/base/dtlstransportinternal.h"
 
 namespace rtc {
 class PacketTransportInterface;
@@ -66,7 +66,7 @@ class StreamInterfaceChannel : public rtc::StreamInterface {
 //   DtlsTransportChannelWrapper {
 //       SSLStreamAdapter* dtls_ {
 //           StreamInterfaceChannel downward_ {
-//               TransportChannelImpl* channel_;
+//               IceTransportInternal* channel_;
 //           }
 //       }
 //   }
@@ -84,15 +84,23 @@ class StreamInterfaceChannel : public rtc::StreamInterface {
 //
 //   - The SSLStreamAdapter writes to downward_->Write()
 //     which translates it into packet writes on channel_.
-class DtlsTransportChannelWrapper : public TransportChannelImpl {
+class DtlsTransportChannelWrapper : public DtlsTransportInternal {
  public:
   // The parameters here are:
   // channel -- the TransportChannel we are wrapping
   explicit DtlsTransportChannelWrapper(TransportChannelImpl* channel);
   ~DtlsTransportChannelWrapper() override;
 
-  void SetIceRole(IceRole role) override { channel_->SetIceRole(role); }
-  IceRole GetIceRole() const override { return channel_->GetIceRole(); }
+  DtlsTransportState dtls_state() const override { return dtls_state_; }
+
+  const std::string& transport_name() const override { return transport_name_; }
+
+  int component() const override { return component_; }
+
+  // Returns false if no local certificate was set, or if the peer doesn't
+  // support DTLS.
+  bool IsDtlsActive() const override { return dtls_active_; }
+
   bool SetLocalCertificate(
       const rtc::scoped_refptr<rtc::RTCCertificate>& certificate) override;
   rtc::scoped_refptr<rtc::RTCCertificate> GetLocalCertificate() const override;
@@ -101,9 +109,6 @@ class DtlsTransportChannelWrapper : public TransportChannelImpl {
                             const uint8_t* digest,
                             size_t digest_len) override;
 
-  // Returns false if no local certificate was set, or if the peer doesn't
-  // support DTLS.
-  bool IsDtlsActive() const override { return dtls_active_; }
 
   // Called to send a packet (via DTLS, if turned on).
   int SendPacket(const char* data,
@@ -111,17 +116,9 @@ class DtlsTransportChannelWrapper : public TransportChannelImpl {
                  const rtc::PacketOptions& options,
                  int flags) override;
 
-  // TransportChannel calls that we forward to the wrapped transport.
-  int SetOption(rtc::Socket::Option opt, int value) override {
-    return channel_->SetOption(opt, value);
-  }
   bool GetOption(rtc::Socket::Option opt, int* value) override {
     return channel_->GetOption(opt, value);
   }
-  int GetError() override { return channel_->GetError(); }
-  bool GetStats(ConnectionInfos* infos) override {
-    return channel_->GetStats(infos);
-  }
 
   virtual bool SetSslMaxProtocolVersion(rtc::SSLProtocolVersion version);
 
@@ -160,51 +157,39 @@ class DtlsTransportChannelWrapper : public TransportChannelImpl {
         : false;
   }
 
-  // TransportChannelImpl calls.
-  TransportChannelState GetState() const override {
-    return channel_->GetState();
-  }
-  void SetIceTiebreaker(uint64_t tiebreaker) override {
-    channel_->SetIceTiebreaker(tiebreaker);
-  }
-  void SetIceParameters(const IceParameters& ice_params) override {
-    channel_->SetIceParameters(ice_params);
-  }
-  void SetRemoteIceParameters(const IceParameters& ice_params) override {
-    channel_->SetRemoteIceParameters(ice_params);
-  }
-  void SetRemoteIceMode(IceMode mode) override {
-    channel_->SetRemoteIceMode(mode);
-  }
+  TransportChannelImpl* ice_transport() override { return channel_; }

[Taylor Brandstetter, 2017/01/03 23:21:59]

Can this be IceTransportInternal instead now (assuming this CL is landed after
the one that introduces IceTransportInternal)?

[Zhi Huang, 2017/01/10 18:30:51]

Yes, I'll merge the IceTransportInternal change into this CL.

 
-  void MaybeStartGathering() override { channel_->MaybeStartGathering(); }
+  // For informational purposes. Tells if the DTLS handshake has finished.
+  // This may be true even if writable() is false, if the remote fingerprint
+  // has not yet been verified.
+  bool IsDtlsConnected();
 
-  IceGatheringState gathering_state() const override {
-    return channel_->gathering_state();
-  }
+  bool receiving() const override { return receiving_; }
 
-  void AddRemoteCandidate(const Candidate& candidate) override {
-    channel_->AddRemoteCandidate(candidate);
-  }
-  void RemoveRemoteCandidate(const Candidate& candidate) override {
-    channel_->RemoveRemoteCandidate(candidate);
-  }
+  bool writable() const override { return writable_; }
 
-  void SetMetricsObserver(webrtc::MetricsObserverInterface* observer) override {
-    channel_->SetMetricsObserver(observer);
-  }
+  int GetError() override { return channel_->GetError(); }

[Taylor Brandstetter, 2017/01/03 23:21:59]

Since this and SetOption just pass through to the ICE channel, can they be
removed? If not, can you leave a TODO and describe what would need to be done?

[Zhi Huang, 2017/01/10 18:30:51]

These functions are from the PacketTransportInterface. But we can hide them by
implementing them in the DtlsTransportInternal.

 
-  void SetIceConfig(const IceConfig& config) override {
-    channel_->SetIceConfig(config);
+  int SetOption(rtc::Socket::Option opt, int value) override {
+    return channel_->SetOption(opt, value);
   }
 
-  // Needed by DtlsTransport.
-  TransportChannelImpl* channel() { return channel_; }
+  bool SetSrtpCiphers(const std::vector<std::string>& ciphers) override {
+    std::vector<int> crypto_suites;
+    for (const auto cipher : ciphers) {
+      crypto_suites.push_back(rtc::SrtpCryptoSuiteFromName(cipher));
+    }
+    return SetSrtpCryptoSuites(crypto_suites);
+  }
 
-  // For informational purposes. Tells if the DTLS handshake has finished.
-  // This may be true even if writable() is false, if the remote fingerprint
-  // has not yet been verified.
-  bool IsDtlsConnected();
+  std::string ToString() const {
+    const char RECEIVING_ABBREV[2] = {'_', 'R'};
+    const char WRITABLE_ABBREV[2] = {'_', 'W'};
+    std::stringstream ss;
+    ss << "DtlsTransport[" << transport_name_ << "|" << component_ << "|"
+       << RECEIVING_ABBREV[receiving()] << WRITABLE_ABBREV[writable()] << "]";
+    return ss.str();
+  }
 
  private:
   void OnWritableState(rtc::PacketTransportInterface* transport);
@@ -221,20 +206,15 @@ class DtlsTransportChannelWrapper : public TransportChannelImpl {
   bool SetupDtls();
   void MaybeStartDtls();
   bool HandleDtlsPacket(const char* data, size_t size);
-  void OnGatheringState(TransportChannelImpl* channel);
-  void OnCandidateGathered(TransportChannelImpl* channel, const Candidate& c);
-  void OnCandidatesRemoved(TransportChannelImpl* channel,
-                           const Candidates& candidates);
-  void OnRoleConflict(TransportChannelImpl* channel);
-  void OnRouteChange(TransportChannel* channel, const Candidate& candidate);
-  void OnSelectedCandidatePairChanged(
-      TransportChannel* channel,
-      CandidatePairInterface* selected_candidate_pair,
-      int last_sent_packet_id,
-      bool ready_to_send);
-  void OnChannelStateChanged(TransportChannelImpl* channel);
   void OnDtlsHandshakeError(rtc::SSLHandshakeError error);
-
+  void set_receiving(bool receiving);
+  void set_writable(bool writable);
+  // Sets the DTLS state, signaling if necessary.
+  void set_dtls_state(DtlsTransportState state);
+
+  std::string transport_name_;
+  int component_;
+  DtlsTransportState dtls_state_ = DTLS_TRANSPORT_NEW;
   rtc::Thread* network_thread_;  // Everything should occur on this thread.
   // Underlying channel, not owned by this class.
   TransportChannelImpl* const channel_;
@@ -254,6 +234,9 @@ class DtlsTransportChannelWrapper : public TransportChannelImpl {
   // received.
   rtc::Buffer cached_client_hello_;
 
+  bool receiving_ = false;
+  bool writable_ = false;
+
   RTC_DISALLOW_COPY_AND_ASSIGN(DtlsTransportChannelWrapper);
 };