Prepare for ICE-renomination

webrtc/p2p/base/port.h

Index: webrtc/p2p/base/port.h
diff --git a/webrtc/p2p/base/port.h b/webrtc/p2p/base/port.h
index 081e81af1d0c32db9a88510181745dd4ce18b673..f958f56380ddfa5013c61bb5b5787b5827b5ea88 100644
--- a/webrtc/p2p/base/port.h
+++ b/webrtc/p2p/base/port.h
@@ -417,11 +417,12 @@ class Connection : public CandidatePairInterface,
                    public sigslot::has_slots<> {
  public:
   struct SentPing {
-    SentPing(const std::string id, int64_t sent_time)
-        : id(id), sent_time(sent_time) {}
+    SentPing(const std::string id, int64_t sent_time, int nomination)
+        : id(id), sent_time(sent_time), nomination(nomination) {}
 
     std::string id;
     int64_t sent_time;
+    int nomination;
   };
 
   // States are from RFC 5245. http://tools.ietf.org/html/rfc5245#section-5.7.4
@@ -511,8 +512,20 @@ class Connection : public CandidatePairInterface,
   bool use_candidate_attr() const { return use_candidate_attr_; }
   void set_use_candidate_attr(bool enable);
 
-  bool nominated() const { return nominated_; }
-  void set_nominated(bool nominated) { nominated_ = nominated; }
+  void set_nomination(int value) { nomination_ = value; }
+
+  int remote_nomination() const { return remote_nomination_; }
+  bool nominated() const { return remote_nomination_ > 0; }
+  // Public for unit tests.
+  void set_remote_nomination(int remote_nomination) {
+    // We don't un-nominate a connection, so we will keep the maximum
+    // nominated value.
+    if (remote_nomination > remote_nomination_) {
+      remote_nomination_ = remote_nomination;
+    }
+  }
+  // Public for unit tests.
+  int acked_nomination() const { return acked_nomination_; }
 
   void set_remote_ice_mode(IceMode mode) {
     remote_ice_mode_ = mode;
@@ -539,7 +552,7 @@ class Connection : public CandidatePairInterface,
   // Called when this connection should try checking writability again.
   int64_t last_ping_sent() const { return last_ping_sent_; }
   void Ping(int64_t now);
-  void ReceivedPingResponse(int rtt);
+  void ReceivedPingResponse(int rtt, const std::string& request_id);
   int64_t last_ping_response_received() const {
     return last_ping_response_received_;
   }
@@ -631,11 +644,19 @@ class Connection : public CandidatePairInterface,
   void set_state(State state);
   void set_connected(bool value);
 
+  int nomination() const { return nomination_; }
+
   void OnMessage(rtc::Message *pmsg);
 
   Port* port_;
   size_t local_candidate_index_;
   Candidate remote_candidate_;
+
+  ConnectionInfo stats_;
+  rtc::RateTracker recv_rate_tracker_;
+  rtc::RateTracker send_rate_tracker_;
+
+ private:
   WriteState write_state_;
   bool receiving_;
   bool connected_;
@@ -645,9 +666,19 @@ class Connection : public CandidatePairInterface,
   // But when peer is ice-lite, this flag "must" be initialized to false and
   // turn on when connection becomes "best connection".
   bool use_candidate_attr_;
-  // Whether this connection has been nominated by the controlling side via
-  // the use_candidate attribute.
-  bool nominated_;
+  // Used by the controlling side to indicate that this connection will be
+  // selected for transmission if the peer supports ICE-renomination when this
+  // value is positive. A larger-value indicates that a connection is nominated
+  // later and should be selected by the controlled side with higher precedence.
+  // A zero-value indicates not nominating this connection.
+  int nomination_ = 0;
+  // The last nominating value that has been acknowledged.
+  int acked_nomination_ = 0;
+  // Used by the controlled side to remember the nomination value received from
+  // the controlling side. When the peer does not support ICE re-nomination,
+  // its value will be 1 if the connection has been nominated.
+  int remote_nomination_ = 0;
+
   IceMode remote_ice_mode_;
   StunRequestManager requests_;
   int rtt_;
@@ -660,12 +691,6 @@ class Connection : public CandidatePairInterface,
   int64_t receiving_unchanged_since_ = 0;
   std::vector<SentPing> pings_since_last_response_;
 
-  rtc::RateTracker recv_rate_tracker_;
-  rtc::RateTracker send_rate_tracker_;
-
-  ConnectionInfo stats_;
-
- private:
   void MaybeAddPrflxCandidate(ConnectionRequest* request,
                               StunMessage* response);