SPDY: Initial support for handling WINDOW_UPDATE frames and some cleanup.

BUG=48100
TEST=net_unittests --gtest_filter="SpdyProtocolTest.ControlFrameStructs:SpdyNetworkTransactionTest.WindowSizeChange:SpdyNetworkTransactionTest.WindowSizeOverflow"

Contributed by: agayev@google.com

Review URL: http://codereview.chromium.org/2807042

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@52352 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 17 insertions, 0 deletions

diff --git a/net/spdy/spdy_stream.cc b/net/spdy/spdy_stream.cc
index 3d68d5d..29fb10a 100644
--- a/net/spdy/spdy_stream.cc
+++ b/net/spdy/spdy_stream.cc
@@ -71,6 +71,23 @@ void SpdyStream::set_spdy_headers(
   request_ = headers;
 }
 
+void SpdyStream::UpdateWindowSize(int delta_window_size) {
+  DCHECK_GE(delta_window_size, 1);
+  int new_window_size = window_size_ + delta_window_size;
+
+  // it's valid for window_size_ to become negative (via an incoming
+  // SETTINGS frame which is handled in SpdySession::OnSettings), in which
+  // case incoming WINDOW_UPDATEs will eventually make it positive;
+  // however, if window_size_ is positive and incoming WINDOW_UPDATE makes
+  // it negative, we have an overflow.
+  if (window_size_ > 0 && new_window_size < 0) {
+    LOG(WARNING) << "Received WINDOW_UPDATE overflows the window size";
+    session_->ResetStream(stream_id_, spdy::FLOW_CONTROL_ERROR);
+    return;
+  }
+  window_size_ = new_window_size;
+}
+
 base::Time SpdyStream::GetRequestTime() const {
   return request_time_;
 }