net/quic/quic_ack_notifier_manager_test.cc

   1 // Copyright (c) 2015 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "net/quic/quic_ack_notifier_manager.h"
   6
   7 #include "net/quic/quic_ack_notifier.h"
   8 #include "net/quic/quic_protocol.h"
   9 #include "net/quic/test_tools/quic_ack_notifier_manager_peer.h"
  10 #include "net/quic/test_tools/quic_test_utils.h"
  11 #include "testing/gtest/include/gtest/gtest.h"
  12
  13 namespace net {
  14 namespace test {
  15 namespace {
  16
  17 // Test fixture for testing AckNotifierManager.  Instantiates a manager and
  18 // provides shared code for adding notifiers and verifying the contents of the
  19 // manager.
  20 class QuicAckNotifierManagerTest : public ::testing::Test {
  21  protected:
  22   AckNotifierManager manager_;
  23   scoped_refptr<MockAckNotifierDelegate> delegate_;
  24   QuicTime::Delta zero_;
  25
  26   QuicAckNotifierManagerTest() : zero_(QuicTime::Delta::Zero()) {
  27     delegate_ = new MockAckNotifierDelegate;
  28   }
  29
  30   ~QuicAckNotifierManagerTest() override {}
  31
  32   size_t CountPackets() const {
  33     return AckNotifierManagerPeer::GetNumberOfRegisteredPackets(&manager_);
  34   }
  35
  36   // Add a mock packet with specified parameters.  The packet with given
  37   // packet number must not exist in the map before.
  38   void AddPacket(QuicPacketNumber packet_number, bool retransmittable) {
  39     // Create a mock packet.
  40     RetransmittableFrames frames(ENCRYPTION_NONE);
  41     SerializedPacket packet(packet_number, PACKET_4BYTE_PACKET_NUMBER,
  42                             /*packet=*/nullptr,
  43                             /*entropy_hash=*/0,
  44                             retransmittable ? &frames : nullptr,
  45                             /*has_ack=*/false,
  46                             /*has_stop_waiting=*/false);
  47
  48     // Create and register a notifier.  Normally, this would be created by
  49     // QuicPacketGenerator.
  50     QuicAckNotifier* notifier = new QuicAckNotifier(delegate_.get());
  51     packet.notifiers.push_back(notifier);
  52
  53     // Ensure that exactly one packet is added.
  54     const size_t old_packet_count = CountPackets();
  55
  56     // Actually add the packet.
  57     manager_.OnSerializedPacket(packet);
  58
  59     // Ensure the change in the number of packets.
  60     EXPECT_EQ(old_packet_count + 1, CountPackets());
  61   }
  62 };
  63
  64 // This test verifies that QuicAckNotifierManager can handle the trivial case of
  65 // received packet notification.
  66 TEST_F(QuicAckNotifierManagerTest, SimpleAck) {
  67   AddPacket(1, false);
  68   AddPacket(2, true);
  69
  70   EXPECT_CALL(*delegate_, OnAckNotification(0, 0, zero_)).Times(2);
  71   manager_.OnPacketAcked(1, zero_);
  72   EXPECT_EQ(1u, CountPackets());
  73   manager_.OnPacketAcked(2, zero_);
  74   EXPECT_EQ(0u, CountPackets());
  75
  76   manager_.OnPacketRemoved(1);
  77   manager_.OnPacketRemoved(2);
  78   EXPECT_EQ(0u, CountPackets());
  79 }
  80
  81 // This test verifies that QuicAckNotifierManager can correctly handle the case
  82 // when some of the packets are lost, which causes retransmission and removal
  83 // from the unacked packet map.
  84 TEST_F(QuicAckNotifierManagerTest, AckWithLosses) {
  85   const size_t retransmitted_packet_size = kDefaultMaxPacketSize;
  86
  87   // Here, we simulate the following scenario:
  88   // 1. We send packets 1 to 5, where only odd-numbered packets are
  89   //    retransmittable.
  90   // 2. The peer acks 1, 2 and 5, but not 3 and 4.
  91   // 3. We retransmit 3 as 6.
  92   // 4. We remove 1 and 2, since we no longer care about them.
  93   // 4. The peer acks 6.
  94   // 5. We remove packets 3 to 6.
  95
  96   // Step 1: send five packets.
  97   AddPacket(1, true);
  98   AddPacket(2, false);
  99   AddPacket(3, true);
 100   AddPacket(4, false);
 101   AddPacket(5, true);
 102
 103   // Step 2: handle acks from peer.
 104   EXPECT_CALL(*delegate_, OnAckNotification(0, 0, zero_)).Times(3);
 105   manager_.OnPacketAcked(1, zero_);
 106   EXPECT_EQ(4u, CountPackets());
 107   manager_.OnPacketAcked(2, zero_);
 108   EXPECT_EQ(3u, CountPackets());
 109   manager_.OnPacketAcked(5, zero_);
 110   EXPECT_EQ(2u, CountPackets());
 111
 112   // Step 3: retransmit 3 as 6.
 113   manager_.OnPacketRetransmitted(3, 6, retransmitted_packet_size);
 114   EXPECT_EQ(2u, CountPackets());
 115
 116   // Step 4: remove 1 and 2.
 117   manager_.OnPacketRemoved(1);
 118   manager_.OnPacketRemoved(2);
 119   EXPECT_EQ(2u, CountPackets());
 120
 121   // Step 4: ack packet 6.
 122   EXPECT_CALL(*delegate_,
 123               OnAckNotification(1, retransmitted_packet_size, zero_)).Times(1);
 124   manager_.OnPacketAcked(6, zero_);
 125   EXPECT_EQ(1u, CountPackets());
 126
 127   // Step 5: remove all packets.  This causes packet 4 to be dropped from the
 128   // map.
 129   manager_.OnPacketRemoved(3);
 130   manager_.OnPacketRemoved(4);
 131   manager_.OnPacketRemoved(5);
 132   manager_.OnPacketRemoved(6);
 133   EXPECT_EQ(0u, CountPackets());
 134 }
 135
 136 // This test verifies that the QuicAckNotifierManager behaves correctly when
 137 // there are many retransmissions.
 138 TEST_F(QuicAckNotifierManagerTest, RepeatedRetransmission) {
 139   AddPacket(1, true);
 140
 141   const size_t packet_size = kDefaultMaxPacketSize;
 142   const size_t times_lost = 100;
 143   const size_t total_size_lost = packet_size * times_lost;
 144   const QuicPacketNumber last_packet = times_lost + 1;
 145
 146   // Retransmit the packet many times.
 147   for (size_t packet_number = 1; packet_number < last_packet; packet_number++) {
 148     manager_.OnPacketRetransmitted(packet_number, packet_number + 1,
 149                                    packet_size);
 150     EXPECT_EQ(1u, CountPackets());
 151   }
 152
 153   // Remove all lost packets.
 154   for (QuicPacketNumber packet = 1; packet < last_packet; packet++) {
 155     manager_.OnPacketRemoved(packet);
 156   }
 157   EXPECT_EQ(1u, CountPackets());
 158
 159   // Finally get the packet acknowledged.
 160   EXPECT_CALL(*delegate_, OnAckNotification(times_lost, total_size_lost, zero_))
 161       .Times(1);
 162   manager_.OnPacketAcked(last_packet, zero_);
 163   EXPECT_EQ(0u, CountPackets());
 164
 165   // Remove the last packet.
 166   manager_.OnPacketRemoved(last_packet);
 167   EXPECT_EQ(0u, CountPackets());
 168 }
 169
 170 }  // namespace
 171 }  // namespace test
 172 }  // namespace net