A few updates on connection states

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 8e7a2592d991661c59bc745e901d523c5b1dd9a8..9a6003c933a3188a5d99da787f2db3e0d94cb24e 100644
--- a/webrtc/p2p/base/port.h
+++ b/webrtc/p2p/base/port.h
@@ -60,6 +60,9 @@ const uint32 WEAK_CONNECTION_RECEIVE_TIMEOUT = 2500;  // 2.5 seconds
 // The length of time we wait before timing out writability on a connection.
 const uint32 CONNECTION_WRITE_TIMEOUT = 15 * 1000;  // 15 seconds
 
+// The length of time we wait before the write state become stale.
+const uint32 CONNECTION_WRITE_STALE_TIMEOUT = 10 * 1000;  // 10 seconds
+
 // The length of time we wait before we become unwritable.
 const uint32 CONNECTION_WRITE_CONNECT_TIMEOUT = 5 * 1000;  // 5 seconds
 
@@ -423,13 +426,15 @@ class Connection : public rtc::MessageHandler,
 
   enum WriteState {
     STATE_WRITABLE          = 0,  // we have received ping responses recently
-    STATE_WRITE_UNRELIABLE  = 1,  // we have had a few ping failures
-    STATE_WRITE_INIT        = 2,  // we have yet to receive a ping response
-    STATE_WRITE_TIMEOUT     = 3,  // we have had a large number of ping failures
+    STATE_WRITE_STALE       = 1,  // we have not sent ping recently.
+    STATE_WRITE_UNRELIABLE  = 2,  // we have had a few ping failures
+    STATE_WRITE_INIT        = 3,  // we have yet to receive a ping response
+    STATE_WRITE_TIMEOUT     = 4,  // we have had a large number of ping failures

[pthatcher1, 2015/09/21 23:49:18]

So the only difference between STALE and UNRELIABLE is whether we are sending
them or not?  I wonder if we can think of a better name here, especially when
related to the STRONG/WEAK analogy with receiving.

[honghaiz3, 2015/09/22 19:35:08]

Dropped this change now. 

   };
 
   WriteState write_state() const { return write_state_; }
   bool writable() const { return write_state_ == STATE_WRITABLE; }
+  bool write_timed_out() const { return write_state_ == STATE_WRITE_TIMEOUT; }
   bool receiving() const { return receiving_; }
 
   // Determines whether the connection has finished connecting.  This can only
@@ -480,6 +485,7 @@ class Connection : public rtc::MessageHandler,
   // side stops using it as well.
   bool pruned() const { return pruned_; }
   void Prune();
+  void Unprune();
 
   bool use_candidate_attr() const { return use_candidate_attr_; }
   void set_use_candidate_attr(bool enable);
@@ -570,9 +576,6 @@ class Connection : public rtc::MessageHandler,
   void set_state(State state);
   void set_connected(bool value);
 
-  // Checks if this connection is useless, and hence, should be destroyed.
-  void CheckTimeout();
-
   void OnMessage(rtc::Message *pmsg);
 
   Port* port_;
@@ -593,6 +596,7 @@ class Connection : public rtc::MessageHandler,
   IceMode remote_ice_mode_;
   StunRequestManager requests_;
   uint32 rtt_;
+  uint32 time_created_;
   uint32 last_ping_sent_;      // last time we sent a ping to the other side
   uint32 last_ping_received_;  // last time we received a ping from the other
                                // side