Change QuicFramer::BuildDataPacket to return a length instead of QuicPacket* in order to reduce mem…

net/quic/quic_framer.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.
 
 #ifndef NET_QUIC_QUIC_FRAMER_H_
 #define NET_QUIC_QUIC_FRAMER_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 268 matching lines @@
                                   QuicPacketNumberLength packet_number_length);
 
   // Returns the associated data from the encrypted packet |encrypted| as a
   // stringpiece.
   static base::StringPiece GetAssociatedDataFromEncryptedPacket(
       const QuicEncryptedPacket& encrypted,
       QuicConnectionIdLength connection_id_length,
       bool includes_version,
       QuicPacketNumberLength packet_number_length);
 
-  // Returns a QuicPacket* that is owned by the caller, is created from
-  // |frames|.  Returns nullptr if the packet could not be created.
-  // The packet must be of size |packet_size|.
-  QuicPacket* BuildDataPacket(const QuicPacketHeader& header,
-                              const QuicFrames& frames,
-                              char* buffer,
-                              size_t packet_length);
+  // Serializes a packet containing |frames| into |buffer|.
+  // Returns the length of the packet, which must not be longer than
+  // |packet_length|.  Returns 0 if it fails to serialize.
+  size_t BuildDataPacket(const QuicPacketHeader& header,
+                         const QuicFrames& frames,
+                         char* buffer,
+                         size_t packet_length);
 
   // Returns a QuicPacket* that is owned by the caller, and is populated with
   // the fields in |header| and |fec|.  Returns nullptr if the packet could
   // not be created.
   QuicPacket* BuildFecPacket(const QuicPacketHeader& header,
                              base::StringPiece redundancy);
 
   // Returns a new public reset packet, owned by the caller.
   static QuicEncryptedPacket* BuildPublicResetPacket(
       const QuicPublicResetPacket& packet);
@@ skipping 238 matching lines @@
   // The time delta computed for the last timestamp frame. This is relative to
   // the creation_time.
   QuicTime::Delta last_timestamp_;
 
   DISALLOW_COPY_AND_ASSIGN(QuicFramer);
 };
 
 }  // namespace net
 
 #endif  // NET_QUIC_QUIC_FRAMER_H_