Land Recent QUIC Changes.

net/quic/quic_flow_controller.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "net/quic/quic_flow_controller.h"
 
 #include "base/basictypes.h"
 #include "net/quic/quic_connection.h"
 #include "net/quic/quic_flags.h"
 #include "net/quic/quic_protocol.h"
 
 namespace net {
 
 #define ENDPOINT (is_server_ ? "Server: " : " Client: ")
 
 QuicFlowController::QuicFlowController(QuicVersion version,
                                        QuicStreamId id,
                                        bool is_server,
                                        uint64 send_window_offset,
                                        uint64 receive_window_offset,
                                        uint64 max_receive_window)
       : id_(id),
         is_enabled_(true),
         is_server_(is_server),
         bytes_consumed_(0),
-        bytes_buffered_(0),
+        highest_received_byte_offset_(0),
         bytes_sent_(0),
         send_window_offset_(send_window_offset),
         receive_window_offset_(receive_window_offset),
         max_receive_window_(max_receive_window),
         last_blocked_send_window_offset_(0) {
   DVLOG(1) << ENDPOINT << "Created flow controller for stream " << id_
            << ", setting initial receive window offset to: "
            << receive_window_offset_
            << ", max receive window to: "
            << max_receive_window_
            << ", setting send window offset to: " << send_window_offset_;
   if (version < QUIC_VERSION_17) {
     DVLOG(1) << ENDPOINT << "Disabling QuicFlowController for stream " << id_
              << ", QUIC version " << version;
     Disable();
   }
 }
 
 void QuicFlowController::AddBytesConsumed(uint64 bytes_consumed) {
   if (!IsEnabled()) {
     return;
   }
 
   bytes_consumed_ += bytes_consumed;
   DVLOG(1) << ENDPOINT << "Stream " << id_ << " consumed: " << bytes_consumed_;
 }
 
-void QuicFlowController::AddBytesBuffered(uint64 bytes_buffered) {
+bool QuicFlowController::UpdateHighestReceivedOffset(uint64 new_offset) {
   if (!IsEnabled()) {
-    return;
+    return false;
   }
 
-  bytes_buffered_ += bytes_buffered;
-  DVLOG(1) << ENDPOINT << "Stream " << id_ << " buffered: " << bytes_buffered_;
-}
-
-void QuicFlowController::RemoveBytesBuffered(uint64 bytes_buffered) {
-  if (!IsEnabled()) {
-    return;
+  // Only update if offset has increased.
+  if (new_offset <= highest_received_byte_offset_) {
+    return false;
   }
 
-  if (bytes_buffered_ < bytes_buffered) {
-    LOG(DFATAL) << "Trying to remove " << bytes_buffered << " bytes, when only "
-                << bytes_buffered_ << " bytes are buffered";
-    bytes_buffered_ = 0;
-    return;
-  }
-
-  bytes_buffered_ -= bytes_buffered;
-  DVLOG(1) << ENDPOINT << "Stream " << id_ << " buffered: " << bytes_buffered_;
+  DVLOG(1) << ENDPOINT << "Stream " << id_
+           << " highest byte offset increased from: "
+           << highest_received_byte_offset_ << " to " << new_offset;
+  highest_received_byte_offset_ = new_offset;
+  return true;
 }
 
 void QuicFlowController::AddBytesSent(uint64 bytes_sent) {
   if (!IsEnabled()) {
     return;
   }
 
   if (bytes_sent_ + bytes_sent > send_window_offset_) {
     LOG(DFATAL) << ENDPOINT << "Stream " << id_ << " Trying to send an extra "
                 << bytes_sent << " bytes, when bytes_sent = " << bytes_sent_
                 << ", and send_window_offset_ = " << send_window_offset_;
     bytes_sent_ = send_window_offset_;
     return;
   }
 
   bytes_sent_ += bytes_sent;
   DVLOG(1) << ENDPOINT << "Stream " << id_ << " sent: " << bytes_sent_;
 }
 
 bool QuicFlowController::FlowControlViolation() {
   if (!IsEnabled()) {
     return false;
   }
 
-  if (receive_window_offset_ < TotalReceivedBytes()) {
-    LOG(ERROR)
-        << ENDPOINT << "Flow control violation on stream " << id_
-        << ", receive window: " << receive_window_offset_
-        << ", bytes received: " << TotalReceivedBytes();
-
+  if (highest_received_byte_offset_ > receive_window_offset_) {
+    LOG(ERROR) << ENDPOINT << "Flow control violation on stream "
+               << id_ << ", receive window offset: "
+               << receive_window_offset_
+               << ", highest received byte offset: "
+               << highest_received_byte_offset_;
     return true;
   }
   return false;
 }
 
 void QuicFlowController::MaybeSendWindowUpdate(QuicConnection* connection) {
   if (!IsEnabled()) {
     return;
   }
 
@@ skipping 77 matching lines @@
   return IsEnabled() && SendWindowSize() == 0;
 }
 
 uint64 QuicFlowController::SendWindowSize() const {
   if (bytes_sent_ > send_window_offset_) {
     return 0;
   }
   return send_window_offset_ - bytes_sent_;
 }
 
-uint64 QuicFlowController::TotalReceivedBytes() const {
-  return bytes_consumed_ + bytes_buffered_;
-}
-
 }  // namespace net