Make QuicPacketCreator be able to serialize packet itself when it does not have room for next strea…

net/quic/quic_packet_creator_test.cc

 // 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.
 
 #include "net/quic/quic_packet_creator.h"
 
 #include <stdint.h>
 
 #include "base/stl_util.h"
 #include "net/quic/crypto/null_encrypter.h"
 #include "net/quic/crypto/quic_decrypter.h"
 #include "net/quic/crypto/quic_encrypter.h"
 #include "net/quic/quic_flags.h"
 #include "net/quic/quic_utils.h"
 #include "net/quic/test_tools/mock_random.h"
 #include "net/quic/test_tools/quic_framer_peer.h"
 #include "net/quic/test_tools/quic_packet_creator_peer.h"
 #include "net/quic/test_tools/quic_test_utils.h"
 #include "net/test/gtest_util.h"
 #include "testing/gmock/include/gmock/gmock.h"
 
 using base::StringPiece;
 using std::ostream;
 using std::string;
 using std::vector;
 using testing::DoAll;
 using testing::InSequence;
 using testing::Return;
 using testing::SaveArg;
+using testing::StrictMock;
 using testing::_;
 
 namespace net {
 namespace test {
 namespace {
 
 // Run tests with combinations of {QuicVersion, ToggleVersionSerialization}.
 struct TestParams {
   TestParams(QuicVersion version,
              bool version_serialization,
@@ skipping 30 matching lines @@
   params.push_back(TestParams(all_supported_versions[0], true,
                               PACKET_0BYTE_CONNECTION_ID, false));
   params.push_back(TestParams(all_supported_versions[0], true,
                               PACKET_1BYTE_CONNECTION_ID, false));
   params.push_back(TestParams(all_supported_versions[0], true,
                               PACKET_4BYTE_CONNECTION_ID, false));
   params.push_back(TestParams(all_supported_versions[0], true, max, true));
   return params;
 }
 
+class MockDelegate : public QuicPacketCreator::DelegateInterface {
+ public:
+  MockDelegate() {}
+  ~MockDelegate() override {}
+
+  MOCK_METHOD1(OnSerializedPacket, void(SerializedPacket* packet));
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(MockDelegate);
+};
+
 class QuicPacketCreatorTest : public ::testing::TestWithParam<TestParams> {
+ public:
+  void ClearSerializedPacket(SerializedPacket* serialized_packet) {
+    if (serialized_packet == nullptr) {
+      return;
+    }
+
+    delete serialized_packet->retransmittable_frames;
+    delete serialized_packet->packet;
+  }
+
+  void SaveSerializedPacket(SerializedPacket* serialized_packet) {
+    if (serialized_packet == nullptr) {
+      return;
+    }
+
+    serialized_packet_ = *serialized_packet;
+    serialized_packet_.packet = serialized_packet->packet->Clone();
+    delete serialized_packet->packet;
+  }
+
  protected:
   QuicPacketCreatorTest()
       : server_framer_(SupportedVersions(GetParam().version),
                        QuicTime::Zero(),
                        Perspective::IS_SERVER),
         client_framer_(SupportedVersions(GetParam().version),
                        QuicTime::Zero(),
                        Perspective::IS_CLIENT),
         connection_id_(2),
         data_("foo"),
-        creator_(connection_id_, &client_framer_, &mock_random_) {
+        creator_(connection_id_, &client_framer_, &mock_random_, &delegate_),
+        serialized_packet_(creator_.NoPacket()) {
     creator_.set_connection_id_length(GetParam().connection_id_length);
     client_framer_.set_visitor(&framer_visitor_);
     client_framer_.set_received_entropy_calculator(&entropy_calculator_);
     server_framer_.set_visitor(&framer_visitor_);
     FLAGS_quic_packet_creator_prefetch = GetParam().copy_use_prefetch;
   }
 
   ~QuicPacketCreatorTest() override {}
 
   void ProcessPacket(QuicEncryptedPacket* encrypted) {
@@ skipping 45 matching lines @@
 
   QuicIOVector MakeIOVector(StringPiece s) {
     return ::net::MakeIOVector(s, &iov_);
   }
 
   static const QuicStreamOffset kOffset = 1u;
 
   QuicFrames frames_;
   QuicFramer server_framer_;
   QuicFramer client_framer_;
-  testing::StrictMock<MockFramerVisitor> framer_visitor_;
+  StrictMock<MockFramerVisitor> framer_visitor_;
+  StrictMock<MockDelegate> delegate_;
   QuicConnectionId connection_id_;
   string data_;
   struct iovec iov_;
   MockRandom mock_random_;
   QuicPacketCreator creator_;
   MockEntropyCalculator entropy_calculator_;
+  SerializedPacket serialized_packet_;
 };
 
 // Run all packet creator tests with all supported versions of QUIC, and with
 // and without version in the packet header, as well as doing a run for each
 // length of truncated connection id.
 INSTANTIATE_TEST_CASE_P(QuicPacketCreatorTests,
                         QuicPacketCreatorTest,
                         ::testing::ValuesIn(GetTestParams()));
 
 TEST_P(QuicPacketCreatorTest, SerializeFrames) {
@@ skipping 73 matching lines @@
   }
   ProcessPacket(serialized.packet);
   delete serialized.packet;
 }
 
 TEST_P(QuicPacketCreatorTest, SerializeChangingSequenceNumberLength) {
   frames_.push_back(QuicFrame(new QuicAckFrame(MakeAckFrame(0u))));
   creator_.AddSavedFrame(frames_[0]);
   QuicPacketCreatorPeer::SetNextPacketNumberLength(&creator_,
                                                    PACKET_4BYTE_PACKET_NUMBER);
-  char buffer[kMaxPacketSize];
-  SerializedPacket serialized =
-      creator_.SerializePacket(buffer, kMaxPacketSize);
+
+  EXPECT_CALL(delegate_, OnSerializedPacket(_))
+      .WillRepeatedly(
+          Invoke(this, &QuicPacketCreatorTest::SaveSerializedPacket));
+  creator_.Flush();
   // The packet number length will not change mid-packet.
-  EXPECT_EQ(PACKET_1BYTE_PACKET_NUMBER, serialized.packet_number_length);
+  EXPECT_EQ(PACKET_1BYTE_PACKET_NUMBER,
+            serialized_packet_.packet_number_length);
 
   {
     InSequence s;
     EXPECT_CALL(framer_visitor_, OnPacket());
     EXPECT_CALL(framer_visitor_, OnUnauthenticatedPublicHeader(_));
     EXPECT_CALL(framer_visitor_, OnUnauthenticatedHeader(_));
     EXPECT_CALL(framer_visitor_, OnDecryptedPacket(_));
     EXPECT_CALL(framer_visitor_, OnPacketHeader(_));
     EXPECT_CALL(framer_visitor_, OnAckFrame(_));
     EXPECT_CALL(framer_visitor_, OnPacketComplete());
   }
-  ProcessPacket(serialized.packet);
-  delete serialized.packet;
+  ProcessPacket(serialized_packet_.packet);
+  ClearSerializedPacket(&serialized_packet_);
 
   creator_.AddSavedFrame(frames_[0]);
-  serialized = creator_.SerializePacket(buffer, kMaxPacketSize);
+  creator_.Flush();
   // Now the actual packet number length should have changed.
-  EXPECT_EQ(PACKET_4BYTE_PACKET_NUMBER, serialized.packet_number_length);
+  EXPECT_EQ(PACKET_4BYTE_PACKET_NUMBER,
+            serialized_packet_.packet_number_length);
   delete frames_[0].ack_frame;
 
   {
     InSequence s;
     EXPECT_CALL(framer_visitor_, OnPacket());
     EXPECT_CALL(framer_visitor_, OnUnauthenticatedPublicHeader(_));
     EXPECT_CALL(framer_visitor_, OnUnauthenticatedHeader(_));
     EXPECT_CALL(framer_visitor_, OnDecryptedPacket(_));
     EXPECT_CALL(framer_visitor_, OnPacketHeader(_));
     EXPECT_CALL(framer_visitor_, OnAckFrame(_));
     EXPECT_CALL(framer_visitor_, OnPacketComplete());
   }
-  ProcessPacket(serialized.packet);
-  delete serialized.packet;
+  ProcessPacket(serialized_packet_.packet);
+  ClearSerializedPacket(&serialized_packet_);
 }
 
 TEST_P(QuicPacketCreatorTest, ChangeSequenceNumberLengthMidPacket) {
   // Changing the packet number length with queued frames in the creator
   // should hold the change until after any currently queued frames are
   // serialized.
 
   // Packet 1.
   // Queue a frame in the creator.
   EXPECT_FALSE(creator_.HasPendingFrames());
   QuicFrame ack_frame = QuicFrame(new QuicAckFrame(MakeAckFrame(0u)));
   creator_.AddSavedFrame(ack_frame);
 
   // Now change packet number length.
   QuicPacketCreatorPeer::SetNextPacketNumberLength(&creator_,
                                                    PACKET_4BYTE_PACKET_NUMBER);
 
   // Add a STOP_WAITING frame since it contains a packet number,
   // whose length should be 1.
   QuicStopWaitingFrame stop_waiting_frame;
   EXPECT_TRUE(creator_.AddSavedFrame(QuicFrame(&stop_waiting_frame)));
   EXPECT_TRUE(creator_.HasPendingFrames());
 
   // Ensure the packet is successfully created.
-  char buffer[kMaxPacketSize];
-  SerializedPacket serialized =
-      creator_.SerializePacket(buffer, kMaxPacketSize);
-  ASSERT_TRUE(serialized.packet);
-  EXPECT_EQ(PACKET_1BYTE_PACKET_NUMBER, serialized.packet_number_length);
+  EXPECT_CALL(delegate_, OnSerializedPacket(_))
+      .WillRepeatedly(
+          Invoke(this, &QuicPacketCreatorTest::SaveSerializedPacket));
+  creator_.Flush();
+  ASSERT_TRUE(serialized_packet_.packet);
+  EXPECT_EQ(PACKET_1BYTE_PACKET_NUMBER,
+            serialized_packet_.packet_number_length);
 
   // Verify that header in transmitted packet has 1 byte sequence length.
   QuicPacketHeader header;
   {
     InSequence s;
     EXPECT_CALL(framer_visitor_, OnPacket());
     EXPECT_CALL(framer_visitor_, OnUnauthenticatedPublicHeader(_));
     EXPECT_CALL(framer_visitor_, OnUnauthenticatedHeader(_));
     EXPECT_CALL(framer_visitor_, OnDecryptedPacket(_));
     EXPECT_CALL(framer_visitor_, OnPacketHeader(_)).WillOnce(
         DoAll(SaveArg<0>(&header), Return(true)));
     EXPECT_CALL(framer_visitor_, OnAckFrame(_));
     EXPECT_CALL(framer_visitor_, OnStopWaitingFrame(_));
     EXPECT_CALL(framer_visitor_, OnPacketComplete());
   }
-  ProcessPacket(serialized.packet);
+  ProcessPacket(serialized_packet_.packet);
   EXPECT_EQ(PACKET_1BYTE_PACKET_NUMBER,
             header.public_header.packet_number_length);
-  delete serialized.packet;
+  ClearSerializedPacket(&serialized_packet_);
 
   // Packet 2.
   EXPECT_FALSE(creator_.HasPendingFrames());
   // Generate Packet 2 with one frame -- packet number length should now
   // change to 4 bytes.
   EXPECT_TRUE(creator_.AddSavedFrame(QuicFrame(&stop_waiting_frame)));
   EXPECT_TRUE(creator_.HasPendingFrames());
 
   // Ensure the packet is successfully created.
-  serialized = creator_.SerializePacket(buffer, kMaxPacketSize);
-  ASSERT_TRUE(serialized.packet);
-  EXPECT_EQ(PACKET_4BYTE_PACKET_NUMBER, serialized.packet_number_length);
+  creator_.Flush();
+  ASSERT_TRUE(serialized_packet_.packet);
+  EXPECT_EQ(PACKET_4BYTE_PACKET_NUMBER,
+            serialized_packet_.packet_number_length);
 
   // Verify that header in transmitted packet has 4 byte sequence length.
   {
     InSequence s;
     EXPECT_CALL(framer_visitor_, OnPacket());
     EXPECT_CALL(framer_visitor_, OnUnauthenticatedPublicHeader(_));
     EXPECT_CALL(framer_visitor_, OnUnauthenticatedHeader(_));
     EXPECT_CALL(framer_visitor_, OnDecryptedPacket(_));
     EXPECT_CALL(framer_visitor_, OnPacketHeader(_)).WillOnce(
         DoAll(SaveArg<0>(&header), Return(true)));
     EXPECT_CALL(framer_visitor_, OnStopWaitingFrame(_));
     EXPECT_CALL(framer_visitor_, OnPacketComplete());
   }
-  ProcessPacket(serialized.packet);
+  ProcessPacket(serialized_packet_.packet);
   EXPECT_EQ(PACKET_4BYTE_PACKET_NUMBER,
             header.public_header.packet_number_length);
 
-  delete serialized.packet;
+  ClearSerializedPacket(&serialized_packet_);
   delete ack_frame.ack_frame;
 }
 
 TEST_P(QuicPacketCreatorTest, SerializeWithFECChangingSequenceNumberLength) {
   // Test goal is to test the following sequence (P1 => generate Packet 1):
   // P1 <change seq num length> P2 FEC,
   // and we expect that packet number length should not change until the end
   // of the open FEC group.
 
   // Enable FEC protection, and send FEC packet every 6 packets.
   EXPECT_TRUE(SwitchFecProtectionOn(6));
   // Should return false since we do not have enough packets in the FEC group to
   // trigger an FEC packet.
   ASSERT_FALSE(creator_.ShouldSendFec(/*force_close=*/false));
   frames_.push_back(QuicFrame(new QuicAckFrame(MakeAckFrame(0u))));
 
   // Generate Packet 1.
   creator_.AddSavedFrame(frames_[0]);
   // Change the packet number length mid-FEC group and it should not change.
   QuicPacketCreatorPeer::SetNextPacketNumberLength(&creator_,
                                                    PACKET_4BYTE_PACKET_NUMBER);
-  char buffer[kMaxPacketSize];
-  SerializedPacket serialized =
-      creator_.SerializePacket(buffer, kMaxPacketSize);
-  EXPECT_EQ(PACKET_1BYTE_PACKET_NUMBER, serialized.packet_number_length);
+  EXPECT_CALL(delegate_, OnSerializedPacket(_))
+      .WillRepeatedly(
+          Invoke(this, &QuicPacketCreatorTest::SaveSerializedPacket));
+  creator_.Flush();
+  EXPECT_EQ(PACKET_1BYTE_PACKET_NUMBER,
+            serialized_packet_.packet_number_length);
 
   {
     InSequence s;
     EXPECT_CALL(framer_visitor_, OnPacket());
     EXPECT_CALL(framer_visitor_, OnUnauthenticatedPublicHeader(_));
     EXPECT_CALL(framer_visitor_, OnUnauthenticatedHeader(_));
     EXPECT_CALL(framer_visitor_, OnDecryptedPacket(_));
     EXPECT_CALL(framer_visitor_, OnPacketHeader(_));
     EXPECT_CALL(framer_visitor_, OnFecProtectedPayload(_));
     EXPECT_CALL(framer_visitor_, OnAckFrame(_));
     EXPECT_CALL(framer_visitor_, OnPacketComplete());
   }
-  ProcessPacket(serialized.packet);
-  delete serialized.packet;
+  ProcessPacket(serialized_packet_.packet);
+  ClearSerializedPacket(&serialized_packet_);
 
   // Generate Packet 2.
   creator_.AddSavedFrame(frames_[0]);
-  serialized = creator_.SerializePacket(buffer, kMaxPacketSize);
-  EXPECT_EQ(PACKET_1BYTE_PACKET_NUMBER, serialized.packet_number_length);
+  creator_.Flush();
+  EXPECT_EQ(PACKET_1BYTE_PACKET_NUMBER,
+            serialized_packet_.packet_number_length);
 
   {
     InSequence s;
     EXPECT_CALL(framer_visitor_, OnPacket());
     EXPECT_CALL(framer_visitor_, OnUnauthenticatedPublicHeader(_));
     EXPECT_CALL(framer_visitor_, OnUnauthenticatedHeader(_));
     EXPECT_CALL(framer_visitor_, OnDecryptedPacket(_));
     EXPECT_CALL(framer_visitor_, OnPacketHeader(_));
     EXPECT_CALL(framer_visitor_, OnFecProtectedPayload(_));
     EXPECT_CALL(framer_visitor_, OnAckFrame(_));
     EXPECT_CALL(framer_visitor_, OnPacketComplete());
   }
-  ProcessPacket(serialized.packet);
-  delete serialized.packet;
+  ProcessPacket(serialized_packet_.packet);
+  ClearSerializedPacket(&serialized_packet_);
 
   // Should return false since we do not have enough packets in the FEC group to
   // trigger an FEC packet.
   ASSERT_FALSE(creator_.ShouldSendFec(/*force_close=*/false));
   // Should return true since there are packets in the FEC group.
   ASSERT_TRUE(creator_.ShouldSendFec(/*force_close=*/true));
 
   // Force generation of FEC packet.
-  serialized = creator_.SerializeFec(buffer, kMaxPacketSize);
+  char buffer[kMaxPacketSize];
+  SerializedPacket serialized = creator_.SerializeFec(buffer, kMaxPacketSize);
   EXPECT_EQ(PACKET_1BYTE_PACKET_NUMBER, serialized.packet_number_length);
   ASSERT_EQ(3u, serialized.packet_number);
 
   {
     InSequence s;
     EXPECT_CALL(framer_visitor_, OnPacket());
     EXPECT_CALL(framer_visitor_, OnUnauthenticatedPublicHeader(_));
     EXPECT_CALL(framer_visitor_, OnUnauthenticatedHeader(_));
     EXPECT_CALL(framer_visitor_, OnDecryptedPacket(_));
     EXPECT_CALL(framer_visitor_, OnPacketHeader(_));
     EXPECT_CALL(framer_visitor_, OnFecData(_));
     EXPECT_CALL(framer_visitor_, OnPacketComplete());
   }
   ProcessPacket(serialized.packet);
-  delete serialized.packet;
+  ClearSerializedPacket(&serialized);
 
   // Ensure the next FEC group starts using the new packet number length.
   serialized = creator_.SerializeAllFrames(frames_, buffer, kMaxPacketSize);
   EXPECT_EQ(PACKET_4BYTE_PACKET_NUMBER, serialized.packet_number_length);
   delete frames_[0].ack_frame;
-  delete serialized.packet;
+  ClearSerializedPacket(&serialized);
 }
 
 TEST_P(QuicPacketCreatorTest, ReserializeFramesWithSequenceNumberLength) {
   // If the original packet number length, the current packet number
   // length, and the configured send packet number length are different, the
   // retransmit must sent with the original length and the others do not change.
   QuicPacketCreatorPeer::SetNextPacketNumberLength(&creator_,
                                                    PACKET_4BYTE_PACKET_NUMBER);
   QuicPacketCreatorPeer::SetPacketNumberLength(&creator_,
                                                PACKET_2BYTE_PACKET_NUMBER);
@@ skipping 169 matching lines @@
   EXPECT_TRUE(creator_.HasPendingFrames());
 
   // Enable FEC protection, and send FEC packet every 6 packets.
   creator_.set_max_packets_per_fec_group(6);
   EXPECT_TRUE(creator_.IsFecEnabled());
   EXPECT_DFATAL(creator_.StartFecProtectingPackets(),
                 "Cannot start FEC protection with pending frames.");
   EXPECT_FALSE(creator_.IsFecProtected());
 
   // Serialize packet for transmission.
-  char buffer[kMaxPacketSize];
-  SerializedPacket serialized =
-      creator_.SerializePacket(buffer, kMaxPacketSize);
-  delete serialized.packet;
-  delete serialized.retransmittable_frames;
+  EXPECT_CALL(delegate_, OnSerializedPacket(_))
+      .WillOnce(Invoke(this, &QuicPacketCreatorTest::ClearSerializedPacket));
+  creator_.Flush();
   EXPECT_FALSE(creator_.HasPendingFrames());
 
   // Since all pending frames have been serialized, turning FEC on should work.
   creator_.StartFecProtectingPackets();
   EXPECT_TRUE(creator_.IsFecProtected());
 }
 
 TEST_P(QuicPacketCreatorTest, ConsumeData) {
   QuicFrame frame;
   QuicIOVector io_vector(MakeIOVector("test"));
@@ skipping 34 matching lines @@
                           + GetEncryptionOverhead();
   for (size_t i = overhead; i < overhead + 100; ++i) {
     creator_.SetMaxPacketLength(i);
     const bool should_have_room = i > overhead + GetStreamFrameOverhead(
         NOT_IN_FEC_GROUP);
     ASSERT_EQ(should_have_room, creator_.HasRoomForStreamFrame(
                                     kClientDataStreamId1, kOffset));
     if (should_have_room) {
       QuicFrame frame;
       QuicIOVector io_vector(MakeIOVector("testdata"));
+      EXPECT_CALL(delegate_, OnSerializedPacket(_))
+          .WillRepeatedly(
+              Invoke(this, &QuicPacketCreatorTest::ClearSerializedPacket));
       ASSERT_TRUE(creator_.ConsumeData(kClientDataStreamId1, io_vector, 0u,
                                        kOffset, false, false, &frame));
       ASSERT_TRUE(frame.stream_frame);
       size_t bytes_consumed = frame.stream_frame->data.length();
       EXPECT_LT(0u, bytes_consumed);
-      char buffer[kMaxPacketSize];
-      SerializedPacket serialized_packet =
-          creator_.SerializePacket(buffer, kMaxPacketSize);
-      ASSERT_TRUE(serialized_packet.packet);
-      delete serialized_packet.packet;
-      delete serialized_packet.retransmittable_frames;
+      creator_.Flush();
     }
   }
 }
 
 TEST_P(QuicPacketCreatorTest, StreamFrameConsumption) {
   // Compute the total overhead for a single frame in packet.
-  const size_t overhead = GetPacketHeaderOverhead(NOT_IN_FEC_GROUP)
-      + GetEncryptionOverhead() + GetStreamFrameOverhead(NOT_IN_FEC_GROUP);
+  const size_t overhead = GetPacketHeaderOverhead(NOT_IN_FEC_GROUP) +
+                          GetEncryptionOverhead() +
+                          GetStreamFrameOverhead(NOT_IN_FEC_GROUP);
   size_t capacity = kDefaultMaxPacketSize - overhead;
   // Now, test various sizes around this size.
   for (int delta = -5; delta <= 5; ++delta) {
     string data(capacity + delta, 'A');
     size_t bytes_free = delta > 0 ? 0 : 0 - delta;
     QuicFrame frame;
     QuicIOVector io_vector(MakeIOVector(data));
-    ASSERT_TRUE(creator_.ConsumeData(kClientDataStreamId1, io_vector, 0u,
-                                     kOffset, false, false, &frame));
-    ASSERT_TRUE(frame.stream_frame);
-    size_t bytes_consumed = frame.stream_frame->data.length();
+    UniqueStreamBuffer stream_buffer;
+    size_t bytes_consumed = QuicPacketCreatorPeer::CreateStreamFrame(
+        &creator_, kClientDataStreamId1, io_vector, 0u, kOffset, false, &frame,
+        &stream_buffer);
     EXPECT_EQ(capacity - bytes_free, bytes_consumed);
 
+    ASSERT_TRUE(creator_.AddSavedFrame(frame));
     // BytesFree() returns bytes available for the next frame, which will
     // be two bytes smaller since the stream frame would need to be grown.
     EXPECT_EQ(2u, creator_.ExpansionOnNewFrame());
     size_t expected_bytes_free = bytes_free < 3 ? 0 : bytes_free - 2;
     EXPECT_EQ(expected_bytes_free, creator_.BytesFree()) << "delta: " << delta;
-    char buffer[kMaxPacketSize];
-    SerializedPacket serialized_packet =
-        creator_.SerializePacket(buffer, kMaxPacketSize);
-    ASSERT_TRUE(serialized_packet.packet);
-    delete serialized_packet.packet;
-    delete serialized_packet.retransmittable_frames;
+    EXPECT_CALL(delegate_, OnSerializedPacket(_))
+        .WillOnce(Invoke(this, &QuicPacketCreatorTest::SaveSerializedPacket));
+    creator_.Flush();
+    ASSERT_TRUE(serialized_packet_.packet);
+    ClearSerializedPacket(&serialized_packet_);
   }
 }
 
 TEST_P(QuicPacketCreatorTest, StreamFrameConsumptionWithFec) {
   // Enable FEC protection, and send FEC packet every 6 packets.
   EXPECT_TRUE(SwitchFecProtectionOn(6));
   // Compute the total overhead for a single frame in packet.
-  const size_t overhead = GetPacketHeaderOverhead(IN_FEC_GROUP)
-      + GetEncryptionOverhead() + GetStreamFrameOverhead(IN_FEC_GROUP);
+  const size_t overhead = GetPacketHeaderOverhead(IN_FEC_GROUP) +
+                          GetEncryptionOverhead() +
+                          GetStreamFrameOverhead(IN_FEC_GROUP);
   size_t capacity = kDefaultMaxPacketSize - overhead;
   // Now, test various sizes around this size.
   for (int delta = -5; delta <= 5; ++delta) {
     string data(capacity + delta, 'A');
     size_t bytes_free = delta > 0 ? 0 : 0 - delta;
     QuicFrame frame;
     QuicIOVector io_vector(MakeIOVector(data));
-    ASSERT_TRUE(creator_.ConsumeData(kClientDataStreamId1, io_vector, 0u,
-                                     kOffset, false, false, &frame));
-    ASSERT_TRUE(frame.stream_frame);
-    size_t bytes_consumed = frame.stream_frame->data.length();;
+    UniqueStreamBuffer stream_buffer;
+    size_t bytes_consumed = QuicPacketCreatorPeer::CreateStreamFrame(
+        &creator_, kClientDataStreamId1, io_vector, 0u, kOffset, false, &frame,
+        &stream_buffer);
     EXPECT_EQ(capacity - bytes_free, bytes_consumed);
 
+    ASSERT_TRUE(creator_.AddSavedFrame(frame));
     // BytesFree() returns bytes available for the next frame. Since stream
     // frame does not grow for FEC protected packets, this should be the same
     // as bytes_free (bound by 0).
     EXPECT_EQ(0u, creator_.ExpansionOnNewFrame());
     size_t expected_bytes_free = bytes_free > 0 ? bytes_free : 0;
     EXPECT_EQ(expected_bytes_free, creator_.BytesFree()) << "delta: " << delta;
-    char buffer[kMaxPacketSize];
-    SerializedPacket serialized_packet =
-        creator_.SerializePacket(buffer, kMaxPacketSize);
-    ASSERT_TRUE(serialized_packet.packet);
-    delete serialized_packet.packet;
-    delete serialized_packet.retransmittable_frames;
+    EXPECT_CALL(delegate_, OnSerializedPacket(_))
+        .WillOnce(Invoke(this, &QuicPacketCreatorTest::SaveSerializedPacket));
+    creator_.Flush();
+    ASSERT_TRUE(serialized_packet_.packet);
+    ClearSerializedPacket(&serialized_packet_);
   }
 }
 
 TEST_P(QuicPacketCreatorTest, CryptoStreamFramePacketPadding) {
   // Compute the total overhead for a single frame in packet.
   const size_t overhead = GetPacketHeaderOverhead(NOT_IN_FEC_GROUP)
       + GetEncryptionOverhead() + GetStreamFrameOverhead(NOT_IN_FEC_GROUP);
   ASSERT_GT(kMaxPacketSize, overhead);
   size_t capacity = kDefaultMaxPacketSize - overhead;
   // Now, test various sizes around this size.
   for (int delta = -5; delta <= 5; ++delta) {
     string data(capacity + delta, 'A');
     size_t bytes_free = delta > 0 ? 0 : 0 - delta;
 
     QuicFrame frame;
     QuicIOVector io_vector(MakeIOVector(data));
+    EXPECT_CALL(delegate_, OnSerializedPacket(_))
+        .WillRepeatedly(
+            Invoke(this, &QuicPacketCreatorTest::SaveSerializedPacket));
     ASSERT_TRUE(creator_.ConsumeData(kCryptoStreamId, io_vector, 0u, kOffset,
                                      false, true, &frame));
     ASSERT_TRUE(frame.stream_frame);
     size_t bytes_consumed = frame.stream_frame->data.length();
     EXPECT_LT(0u, bytes_consumed);
-    char buffer[kMaxPacketSize];
-    SerializedPacket serialized_packet =
-        creator_.SerializePacket(buffer, kMaxPacketSize);
-    ASSERT_TRUE(serialized_packet.packet);
+    creator_.Flush();
+    ASSERT_TRUE(serialized_packet_.packet);
     // If there is not enough space in the packet to fit a padding frame
     // (1 byte) and to expand the stream frame (another 2 bytes) the packet
     // will not be padded.
     if (bytes_free < 3) {
       EXPECT_EQ(kDefaultMaxPacketSize - bytes_free,
-                serialized_packet.packet->length());
+                serialized_packet_.packet->length());
     } else {
-      EXPECT_EQ(kDefaultMaxPacketSize, serialized_packet.packet->length());
+      EXPECT_EQ(kDefaultMaxPacketSize, serialized_packet_.packet->length());
     }
-    delete serialized_packet.packet;
-    delete serialized_packet.retransmittable_frames;
+    ClearSerializedPacket(&serialized_packet_);
   }
 }
 
 TEST_P(QuicPacketCreatorTest, NonCryptoStreamFramePacketNonPadding) {
   // Compute the total overhead for a single frame in packet.
   const size_t overhead = GetPacketHeaderOverhead(NOT_IN_FEC_GROUP)
       + GetEncryptionOverhead() + GetStreamFrameOverhead(NOT_IN_FEC_GROUP);
   ASSERT_GT(kDefaultMaxPacketSize, overhead);
   size_t capacity = kDefaultMaxPacketSize - overhead;
   // Now, test various sizes around this size.
   for (int delta = -5; delta <= 5; ++delta) {
     string data(capacity + delta, 'A');
     size_t bytes_free = delta > 0 ? 0 : 0 - delta;
 
     QuicFrame frame;
     QuicIOVector io_vector(MakeIOVector(data));
+    EXPECT_CALL(delegate_, OnSerializedPacket(_))
+        .WillOnce(Invoke(this, &QuicPacketCreatorTest::SaveSerializedPacket));
     ASSERT_TRUE(creator_.ConsumeData(kClientDataStreamId1, io_vector, 0u,
                                      kOffset, false, false, &frame));
     ASSERT_TRUE(frame.stream_frame);
     size_t bytes_consumed = frame.stream_frame->data.length();
     EXPECT_LT(0u, bytes_consumed);
-    char buffer[kMaxPacketSize];
-    SerializedPacket serialized_packet =
-        creator_.SerializePacket(buffer, kMaxPacketSize);
-    ASSERT_TRUE(serialized_packet.packet);
+    creator_.Flush();
+    ASSERT_TRUE(serialized_packet_.packet);
     if (bytes_free > 0) {
       EXPECT_EQ(kDefaultMaxPacketSize - bytes_free,
-                serialized_packet.packet->length());
+                serialized_packet_.packet->length());
     } else {
-      EXPECT_EQ(kDefaultMaxPacketSize, serialized_packet.packet->length());
+      EXPECT_EQ(kDefaultMaxPacketSize, serialized_packet_.packet->length());
     }
-    delete serialized_packet.packet;
-    delete serialized_packet.retransmittable_frames;
+    ClearSerializedPacket(&serialized_packet_);
   }
 }
 
 TEST_P(QuicPacketCreatorTest, SerializeVersionNegotiationPacket) {
   QuicFramerPeer::SetPerspective(&client_framer_, Perspective::IS_SERVER);
   QuicVersionVector versions;
   versions.push_back(test::QuicVersionMax());
   scoped_ptr<QuicEncryptedPacket> encrypted(
       creator_.SerializeVersionNegotiationPacket(versions));
 
@@ skipping 98 matching lines @@
   // A string larger than fits into a frame.
   size_t payload_length;
   creator_.SetMaxPacketLength(GetPacketLengthForOneStream(
       client_framer_.version(),
       QuicPacketCreatorPeer::SendVersionInPacket(&creator_),
       creator_.connection_id_length(), PACKET_1BYTE_PACKET_NUMBER,
       NOT_IN_FEC_GROUP, &payload_length));
   QuicFrame frame;
   const string too_long_payload(payload_length * 2, 'a');
   QuicIOVector io_vector(MakeIOVector(too_long_payload));
+  EXPECT_CALL(delegate_, OnSerializedPacket(_))
+      .WillOnce(Invoke(this, &QuicPacketCreatorTest::SaveSerializedPacket));
   ASSERT_TRUE(creator_.ConsumeData(1u, io_vector, 0u, 0u, true, false, &frame));
   ASSERT_TRUE(frame.stream_frame);
   size_t consumed = frame.stream_frame->data.length();
   EXPECT_EQ(payload_length, consumed);
   const string payload(payload_length, 'a');
   CheckStreamFrame(frame, 1u, payload, 0u, false);
+  creator_.Flush();
+  ClearSerializedPacket(&serialized_packet_);
 }
 
-TEST_P(QuicPacketCreatorTest, AddFrameAndSerialize) {
+TEST_P(QuicPacketCreatorTest, AddFrameAndFlush) {
   if (!GetParam().version_serialization) {
     creator_.StopSendingVersion();
   }
   const size_t max_plaintext_size =
       client_framer_.GetMaxPlaintextSize(creator_.max_packet_length());
   EXPECT_FALSE(creator_.HasPendingFrames());
   EXPECT_EQ(max_plaintext_size -
                 GetPacketHeaderSize(
                     creator_.connection_id_length(),
                     QuicPacketCreatorPeer::SendVersionInPacket(&creator_),
@@ skipping 12 matching lines @@
   ASSERT_TRUE(frame.stream_frame);
   size_t consumed = frame.stream_frame->data.length();
   EXPECT_EQ(4u, consumed);
   EXPECT_TRUE(creator_.HasPendingFrames());
 
   QuicPaddingFrame padding_frame;
   EXPECT_TRUE(creator_.AddSavedFrame(QuicFrame(padding_frame)));
   EXPECT_TRUE(creator_.HasPendingFrames());
   EXPECT_EQ(0u, creator_.BytesFree());
 
+  // Packet is full. Creator will flush.
+  EXPECT_CALL(delegate_, OnSerializedPacket(_))
+      .WillOnce(Invoke(this, &QuicPacketCreatorTest::SaveSerializedPacket));
   EXPECT_FALSE(creator_.AddSavedFrame(QuicFrame(&ack_frame)));
 
   // Ensure the packet is successfully created.
-  char buffer[kMaxPacketSize];
-  SerializedPacket serialized =
-      creator_.SerializePacket(buffer, kMaxPacketSize);
-  ASSERT_TRUE(serialized.packet);
-  delete serialized.packet;
-  ASSERT_TRUE(serialized.retransmittable_frames);
-  RetransmittableFrames* retransmittable = serialized.retransmittable_frames;
+  ASSERT_TRUE(serialized_packet_.packet);
+  ASSERT_TRUE(serialized_packet_.retransmittable_frames);
+  RetransmittableFrames* retransmittable =
+      serialized_packet_.retransmittable_frames;
   ASSERT_EQ(1u, retransmittable->frames().size());
   EXPECT_EQ(STREAM_FRAME, retransmittable->frames()[0].type);
   ASSERT_TRUE(retransmittable->frames()[0].stream_frame);
-  delete serialized.retransmittable_frames;
+  ClearSerializedPacket(&serialized_packet_);
 
   EXPECT_FALSE(creator_.HasPendingFrames());
   EXPECT_EQ(max_plaintext_size -
                 GetPacketHeaderSize(
                     creator_.connection_id_length(),
                     QuicPacketCreatorPeer::SendVersionInPacket(&creator_),
                     PACKET_1BYTE_PACKET_NUMBER, NOT_IN_FEC_GROUP),
             creator_.BytesFree());
 }
 
@@ skipping 23 matching lines @@
   QuicIOVector io_vector(MakeIOVector("test"));
   ASSERT_TRUE(
       creator_.ConsumeData(2u, io_vector, 0u, 0u, false, false, &frame));
   ASSERT_TRUE(frame.stream_frame);
   size_t consumed = frame.stream_frame->data.length();
   EXPECT_EQ(4u, consumed);
   EXPECT_TRUE(creator_.HasPendingFrames());
 
   // Ensure the packet is successfully created, and the packet size estimate
   // matches the serialized packet length.
-  EXPECT_CALL(entropy_calculator_,
-             EntropyHash(_)).WillOnce(testing::Return(0));
+  EXPECT_CALL(entropy_calculator_, EntropyHash(_)).WillOnce(testing::Return(0));
+  EXPECT_CALL(delegate_, OnSerializedPacket(_))
+      .WillOnce(Invoke(this, &QuicPacketCreatorTest::SaveSerializedPacket));
   size_t est_packet_size = creator_.PacketSize();
-  char buffer[kMaxPacketSize];
-  SerializedPacket serialized =
-      creator_.SerializePacket(buffer, kMaxPacketSize);
-  ASSERT_TRUE(serialized.packet);
-  EXPECT_EQ(est_packet_size,
-            client_framer_.GetMaxPlaintextSize(serialized.packet->length()));
-  delete serialized.retransmittable_frames;
-  delete serialized.packet;
+  creator_.Flush();
+  ASSERT_TRUE(serialized_packet_.packet);
+  EXPECT_EQ(est_packet_size, client_framer_.GetMaxPlaintextSize(
+                                 serialized_packet_.packet->length()));
+  ClearSerializedPacket(&serialized_packet_);
 }
 
 TEST_P(QuicPacketCreatorTest, SerializeTruncatedAckFrameWithSmallPacketSize) {
   if (!GetParam().version_serialization) {
     creator_.StopSendingVersion();
   }
   creator_.SetMaxPacketLength(500u);
 
   const size_t max_plaintext_size =
       client_framer_.GetMaxPlaintextSize(creator_.max_packet_length());
   EXPECT_EQ(max_plaintext_size - creator_.PacketSize(), creator_.BytesFree());
 
   // Serialized length of ack frame with 2000 nack ranges should be limited by
   // the packet size.
   QuicAckFrame ack_frame = MakeAckFrameWithNackRanges(2000u, 0u);
   size_t frame_len = client_framer_.GetSerializedFrameLength(
       QuicFrame(&ack_frame), creator_.BytesFree(), true, true, NOT_IN_FEC_GROUP,
       PACKET_1BYTE_PACKET_NUMBER);
   EXPECT_EQ(creator_.BytesFree(), frame_len);
 
   // Add ack frame to creator.
   EXPECT_TRUE(creator_.AddSavedFrame(QuicFrame(&ack_frame)));
   EXPECT_TRUE(creator_.HasPendingFrames());
   EXPECT_EQ(client_framer_.GetMaxPlaintextSize(creator_.max_packet_length()),
             creator_.PacketSize());
   EXPECT_EQ(0u, creator_.BytesFree());
 
   // Ensure the packet is successfully created, and the packet size estimate
   // may not match the serialized packet length.
-  EXPECT_CALL(entropy_calculator_,
-             EntropyHash(_)).WillOnce(Return(0));
+  EXPECT_CALL(entropy_calculator_, EntropyHash(_)).WillOnce(Return(0));
   size_t est_packet_size = creator_.PacketSize();
-  char buffer[kMaxPacketSize];
-  SerializedPacket serialized =
-      creator_.SerializePacket(buffer, kMaxPacketSize);
-  ASSERT_TRUE(serialized.packet);
-  EXPECT_GE(est_packet_size,
-            client_framer_.GetMaxPlaintextSize(serialized.packet->length()));
-  delete serialized.packet;
+  EXPECT_CALL(delegate_, OnSerializedPacket(_))
+      .WillOnce(Invoke(this, &QuicPacketCreatorTest::SaveSerializedPacket));
+  creator_.Flush();
+  ASSERT_TRUE(serialized_packet_.packet);
+  EXPECT_GE(est_packet_size, client_framer_.GetMaxPlaintextSize(
+                                 serialized_packet_.packet->length()));
+  ClearSerializedPacket(&serialized_packet_);
 }
 
 
 TEST_P(QuicPacketCreatorTest, EntropyFlag) {
   frames_.push_back(
       QuicFrame(new QuicStreamFrame(0u, false, 0u, StringPiece())));
 
   char buffer[kMaxPacketSize];
   for (int i = 0; i < 2; ++i) {
     for (int j = 0; j < 64; ++j) {
@@ skipping 75 matching lines @@
   QuicIOVector io_vector(MakeIOVector("test"));
   ASSERT_TRUE(
       creator_.ConsumeData(1u, io_vector, 0u, 0u, false, false, &frame));
   ASSERT_TRUE(frame.stream_frame);
   size_t consumed = frame.stream_frame->data.length();
   EXPECT_EQ(4u, consumed);
   EXPECT_TRUE(creator_.HasPendingFrames());
   EXPECT_DFATAL(creator_.ResetFecGroup(),
                 "Cannot reset FEC group with pending frames.");
 
-  // Serialize packet for transmission.
-  char buffer[kMaxPacketSize];
-  SerializedPacket serialized =
-      creator_.SerializePacket(buffer, kMaxPacketSize);
-  delete serialized.packet;
-  delete serialized.retransmittable_frames;
+  EXPECT_CALL(delegate_, OnSerializedPacket(_))
+      .WillOnce(Invoke(this, &QuicPacketCreatorTest::ClearSerializedPacket));
+  creator_.Flush();
   EXPECT_FALSE(creator_.HasPendingFrames());
 
   // Close the FEC Group.
   creator_.ResetFecGroup();
   EXPECT_FALSE(creator_.IsFecGroupOpen());
 }
 
 }  // namespace
 }  // namespace test
 }  // namespace net