SPDY - implement greedy approach to read all the data and process it

net/spdy/spdy_session.h

Index: net/spdy/spdy_session.h
===================================================================
--- net/spdy/spdy_session.h	(revision 180807)
+++ net/spdy/spdy_session.h	(working copy)
@@ -43,6 +43,10 @@
 // Specifies the maxiumum concurrent streams server could send (via push).
 const int kMaxConcurrentPushedStreams = 1000;
 
+// Specifies the number of bytes read synchronously (without yielding) if the
+// data is available.
+const int kMaxReadBytes = 32 * 1024;

[Ryan Sleevi, 2013/02/06 23:04:46]

I'm not sure I understand why these constants get exposed via the header.
They're implementation details, are they not? Is this only for unit tests?

[ramant (doing other things), 2013/02/07 02:11:07]

This is for unit tests.

+
 class BoundNetLog;
 struct LoadTimingInfo;
 class SpdyStream;
@@ -265,7 +269,7 @@
   void SendWindowUpdate(SpdyStreamId stream_id, int32 delta_window_size);
 
   // If session is closed, no new streams/transactions should be created.
-  bool IsClosed() const { return state_ == CLOSED; }
+  bool IsClosed() const { return state_ == STATE_CLOSED; }
 
   // Closes this session.  This will close all active streams and mark
   // the session as permanently closed.
@@ -422,10 +426,11 @@
       PendingCallbackMap;
 
   enum State {
-    IDLE,
-    CONNECTING,
-    CONNECTED,
-    CLOSED
+    STATE_IDLE,
+    STATE_CONNECTING,
+    STATE_DO_READ,
+    STATE_DO_READ_COMPLETE,
+    STATE_CLOSED
   };
 
   virtual ~SpdySession();
@@ -437,6 +442,21 @@
       scoped_refptr<SpdyStream>* spdy_stream,
       const BoundNetLog& stream_net_log);
 
+  // Start the DoLoop to read data from socket.
+  void StartRead();
+
+  // Try to make progress by reading and processing data.
+  int DoLoop(int result);
+  // The implementations of STATE_DO_READ/STATE_DO_READ_COMPLETE state changes
+  // of the state machine.
+  int DoRead();
+  int DoReadComplete(int bytes_read);
+
+  // Check if session is connected or not.
+  bool IsConnected() const {
+    return state_ == STATE_DO_READ || state_ == STATE_DO_READ_COMPLETE;
+  }
+
   // IO Callbacks
   void OnReadComplete(int result);
   void OnWriteComplete(int result);
@@ -471,10 +491,6 @@
   // haven't received any data in |kHungInterval| time period.
   void CheckPingStatus(base::TimeTicks last_check_time);
 
-  // Start reading from the socket.
-  // Returns OK on success, or an error on failure.
-  net::Error ReadSocket();
-
   // Write current data to the socket.
   void WriteSocketLater();
   void WriteSocket();
@@ -672,7 +688,15 @@
   int streams_pushed_count_;
   int streams_pushed_and_claimed_count_;
   int streams_abandoned_count_;
-  int bytes_received_;
+
+  // |total_bytes_received_| keeps track of all the bytes read by the
+  // SpdySession. It is used by the |Net.SpdySettingsCwnd...| histograms.
+  int total_bytes_received_;
+
+  // |bytes_read_| keeps track of number of bytes read continously in the
+  // DoLoop() without yielding.
+  int bytes_read_;
+
   bool sent_settings_;      // Did this session send settings when it started.
   bool received_settings_;  // Did this session receive at least one settings
                             // frame.