In QUIC, send data is copied to streams rather than frames. Protected by FLAGS_quic_reloadable_flag…

net/quic/core/quic_session.h

 // Copyright (c) 2012 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.
 //
 // A QuicSession, which demuxes a single connection to individual streams.
 
 #ifndef NET_QUIC_CORE_QUIC_SESSION_H_
 #define NET_QUIC_CORE_QUIC_SESSION_H_
 
 #include <cstddef>
@@ skipping 90 matching lines @@
   void OnConnectionMigration(PeerAddressChangeType type) override {}
   // Deletes streams that are safe to be deleted now that it's safe to do so (no
   // other operations are being done on the streams at this time).
   void PostProcessAfterData() override;
   // Adds a connection level WINDOW_UPDATE frame.
   void OnAckNeedsRetransmittableFrame() override;
   bool WillingAndAbleToWrite() const override;
   bool HasPendingHandshake() const override;
   bool HasOpenDynamicStreams() const override;
   void OnPathDegrading() override;
+  void SaveStreamData(QuicStreamId id,
+                      QuicIOVector iov,
+                      size_t iov_offset,
+                      QuicStreamOffset offset,
+                      QuicByteCount data_length) override;
+  bool WriteStreamData(QuicStreamId id,
+                       QuicStreamOffset offset,
+                       QuicByteCount data_length,
+                       QuicDataWriter* writer) override;
 
   // StreamNotifierInterface methods:
   void OnStreamFrameAcked(const QuicStreamFrame& frame,
                           QuicTime::Delta ack_delay_time) override;
   void OnStreamFrameRetransmitted(const QuicStreamFrame& frame) override;
   void OnStreamFrameDiscarded(const QuicStreamFrame& frame) override;
 
   // Called on every incoming packet. Passes |packet| through to |connection_|.
   virtual void ProcessUdpPacket(const QuicSocketAddress& self_address,
                                 const QuicSocketAddress& peer_address,
@@ skipping 141 matching lines @@
 
   // Returns true if this stream should yield writes to another blocked stream.
   bool ShouldYield(QuicStreamId stream_id);
 
   void set_respect_goaway(bool respect_goaway) {
     respect_goaway_ = respect_goaway;
   }
 
   bool use_stream_notifier() const { return use_stream_notifier_; }
 
+  bool streams_own_data() const { return streams_own_data_; }
+
  protected:
   using StaticStreamMap = QuicSmallMap<QuicStreamId, QuicStream*, 2>;
 
   using DynamicStreamMap =
       QuicSmallMap<QuicStreamId, std::unique_ptr<QuicStream>, 10>;
 
   using ClosedStreams = std::vector<std::unique_ptr<QuicStream>>;
 
   using ZombieStreamMap =
       QuicSmallMap<QuicStreamId, std::unique_ptr<QuicStream>, 10>;
@@ skipping 227 matching lines @@
   QuicStreamId currently_writing_stream_id_;
 
   // If this is set to false, the session will ignore peer GOAWAYs and
   // allow the creation of outgoing streams regardless of the high
   // chance they will fail.
   bool respect_goaway_;
 
   // This session is notified on every ack or loss.
   const bool use_stream_notifier_;
 
+  // Streams of this session own their outstanding data. Outstanding data here
+  // means sent data waiting to be acked.
+  const bool streams_own_data_;
+
   DISALLOW_COPY_AND_ASSIGN(QuicSession);
 };
 
 }  // namespace net
 
 #endif  // NET_QUIC_CORE_QUIC_SESSION_H_