relnote: Add a new class QuicBufferedPacketStore which is not in use yet.

net/quic/quic_buffered_packet_store_test.cc

+// Copyright (c) 2016 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_buffered_packet_store.h"
+
+#include <list>
+#include <string>
+
+#include "base/stl_util.h"
+#include "net/quic/test_tools/mock_clock.h"
+#include "net/quic/test_tools/quic_test_utils.h"
+#include "testing/gmock/include/gmock/gmock.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace net {
+
+typedef QuicBufferedPacketStore::BufferedPacket BufferedPacket;
+typedef QuicBufferedPacketStore::EnqueuePacketResult EnqueuePacketResult;
+
+static const size_t kDefaultMaxConnectionsInStore = 100;
+
+namespace test {
+class QuicBufferedPacketStorePeer {
+ public:
+  static QuicAlarm* expiration_alarm(QuicBufferedPacketStore* store) {
+    return store->expiration_alarm_.get();
+  }
+};
+
+namespace {
+
+typedef QuicBufferedPacketStore::BufferedPacket BufferedPacket;
+typedef QuicBufferedPacketStore::BufferedPacketList BufferedPacketList;
+
+class QuicBufferedPacketStoreVisitor
+    : public QuicBufferedPacketStore::VisitorInterface {
+ public:
+  QuicBufferedPacketStoreVisitor() {}
+
+  ~QuicBufferedPacketStoreVisitor() override {}
+
+  void OnExpiredPackets(QuicConnectionId connection_id,
+                        BufferedPacketList early_arrived_packets) override {
+    last_expired_packet_queue_ = std::move(early_arrived_packets);
+  }
+
+  // The packets queue for most recently expirect connection.
+  BufferedPacketList last_expired_packet_queue_;
+};
+
+class QuicBufferedPacketStoreTest : public ::testing::Test {
+ public:
+  QuicBufferedPacketStoreTest()
+      : store_(&visitor_, &clock_, &alarm_factory_),
+        server_address_(Loopback6(), 65535),
+        client_address_(Loopback6(), 65535),
+        data_packet_(packet_content_.data(), packet_content_.size()) {}
+
+ protected:
+  QuicBufferedPacketStoreVisitor visitor_;
+  MockClock clock_;
+  MockAlarmFactory alarm_factory_;
+  QuicBufferedPacketStore store_;
+  IPEndPoint server_address_;
+  IPEndPoint client_address_;
+  std::string packet_content_ = "some encrypted content";
+  QuicEncryptedPacket data_packet_;
+};
+
+TEST_F(QuicBufferedPacketStoreTest, SimpleEnqueueAndDeliverPacket) {
+  QuicConnectionId connection_id = 1;
+  store_.EnqueuePacket(connection_id, data_packet_, server_address_,
+                       client_address_);
+  std::list<BufferedPacket> queue = store_.DeliverPackets(connection_id);
+  ASSERT_EQ(1u, queue.size());
+  // Check content of the only packet in the queue.
+  EXPECT_EQ(packet_content_, queue.front().packet->AsStringPiece());
+  EXPECT_EQ(client_address_, queue.front().client_address);
+  EXPECT_EQ(server_address_, queue.front().server_address);
+  // No more packets on connection 1 should remain in the store.
+  EXPECT_TRUE(store_.DeliverPackets(connection_id).empty());
+}
+
+TEST_F(QuicBufferedPacketStoreTest, DifferentPacketAddressOnOneConnection) {
+  IPEndPoint addr_with_new_port(Loopback4(), 256);
+  QuicConnectionId connection_id = 1;
+  store_.EnqueuePacket(connection_id, data_packet_, server_address_,
+                       client_address_);
+  store_.EnqueuePacket(connection_id, data_packet_, server_address_,
+                       addr_with_new_port);
+  std::list<BufferedPacket> queue = store_.DeliverPackets(connection_id);
+  ASSERT_EQ(2u, queue.size());
+  // The address migration path should be preserved.
+  EXPECT_EQ(client_address_, queue.front().client_address);
+  EXPECT_EQ(addr_with_new_port, queue.back().client_address);
+}
+
+TEST_F(QuicBufferedPacketStoreTest,
+       EnqueueAndDeliverMultiplePacketsOnMultipleConnections) {
+  size_t num_connections = 10;
+  for (QuicConnectionId connection_id = 1; connection_id <= num_connections;
+       ++connection_id) {
+    store_.EnqueuePacket(connection_id, data_packet_, server_address_,
+                         client_address_);
+    store_.EnqueuePacket(connection_id, data_packet_, server_address_,
+                         client_address_);
+  }
+
+  // Deliver packets in reversed order.
+  for (QuicConnectionId connection_id = num_connections; connection_id > 0;
+       --connection_id) {
+    std::list<BufferedPacket> queue = store_.DeliverPackets(connection_id);
+    ASSERT_EQ(2u, queue.size());
+  }
+}
+
+TEST_F(QuicBufferedPacketStoreTest,
+       FailToBufferTooManyPacketsOnExistingConnection) {
+  // Tests that for one connection, only limited number of packets can be
+  // buffered.
+  size_t num_packets = kDefaultMaxUndecryptablePackets + 1;
+  QuicConnectionId connection_id = 1;
+  for (size_t i = 1; i <= num_packets; ++i) {
+    // Only first |kDefaultMaxUndecryptablePackets packets| will be buffered.
+    EnqueuePacketResult result = store_.EnqueuePacket(
+        connection_id, data_packet_, server_address_, client_address_);
+    if (i <= kDefaultMaxUndecryptablePackets) {
+      EXPECT_EQ(EnqueuePacketResult::SUCCESS, result);
+    } else {
+      EXPECT_EQ(EnqueuePacketResult::TOO_MANY_PACKETS, result);
+    }
+  }
+
+  // Only first |kDefaultMaxUndecryptablePackets| packets are kept in the store
+  // and can be delivered.
+  EXPECT_EQ(kDefaultMaxUndecryptablePackets,
+            store_.DeliverPackets(connection_id).size());
+}
+
+TEST_F(QuicBufferedPacketStoreTest, FailToBufferPacketsForTooManyConnections) {
+  // Tests that store can only keep early arrived packets for limited number of
+  // connections.
+  size_t num_connections = kDefaultMaxConnectionsInStore + 1;
+  for (size_t connection_id = 1; connection_id <= num_connections;
+       ++connection_id) {
+    EnqueuePacketResult result = store_.EnqueuePacket(
+        connection_id, data_packet_, server_address_, client_address_);
+    if (connection_id <= kDefaultMaxConnectionsInStore) {
+      EXPECT_EQ(EnqueuePacketResult::SUCCESS, result);
+    } else {
+      EXPECT_EQ(EnqueuePacketResult::TOO_MANY_CONNECTIONS, result);
+    }
+  }
+  // Store only keeps early arrived packets upto |kDefaultMaxConnectionsInStore|
+  // connections.
+  for (size_t connection_id = 1; connection_id <= num_connections;
+       ++connection_id) {
+    std::list<BufferedPacket> queue = store_.DeliverPackets(connection_id);
+    if (connection_id <= kDefaultMaxConnectionsInStore) {
+      EXPECT_EQ(1u, queue.size());
+    } else {
+      EXPECT_EQ(0u, queue.size());
+    }
+  }
+}
+
+TEST_F(QuicBufferedPacketStoreTest, PacketQueueExpiredBeforeDelivery) {
+  QuicConnectionId connection_id = 1;
+  store_.EnqueuePacket(connection_id, data_packet_, server_address_,
+                       client_address_);
+  // Packet for another connection arrive 1ms later.
+  clock_.AdvanceTime(QuicTime::Delta::FromMilliseconds(1));
+  QuicConnectionId connection_id2 = 2;
+  // Use different client address to differetiate packets from different
+  // connections.
+  IPEndPoint another_client_address(Loopback4(), 255);
+  store_.EnqueuePacket(connection_id2, data_packet_, server_address_,
+                       another_client_address);
+  // Advance clock to the time when connection 1 expires.
+  clock_.AdvanceTime(QuicBufferedPacketStorePeer::expiration_alarm(&store_)
+                         ->deadline()
+                         .Subtract(clock_.ApproximateNow()));
+  ASSERT_GE(clock_.ApproximateNow(),
+            QuicBufferedPacketStorePeer::expiration_alarm(&store_)->deadline());
+  // Fire alarm to remove long-staying connection 1 packets.
+  alarm_factory_.FireAlarm(
+      QuicBufferedPacketStorePeer::expiration_alarm(&store_));
+  EXPECT_EQ(1u, visitor_.last_expired_packet_queue_.buffered_packets.size());
+  // Try to deliver packets, but packet queue has been removed so no
+  // packets can be returned.
+  ASSERT_EQ(0u, store_.DeliverPackets(connection_id).size());
+
+  // Deliver packets on connection 2. And the queue for connection 2 should be
+  // returned.
+  std::list<BufferedPacket> queue = store_.DeliverPackets(connection_id2);
+  ASSERT_EQ(1u, queue.size());
+  // Packets in connection 2 should use another client address.
+  EXPECT_EQ(another_client_address, queue.front().client_address);
+
+  // Test the alarm is reset by enqueueing 2 packets for 3rd connection and wait
+  // for them to expire.
+  QuicConnectionId connection_id3 = 3;
+  store_.EnqueuePacket(connection_id3, data_packet_, server_address_,
+                       client_address_);
+  store_.EnqueuePacket(connection_id3, data_packet_, server_address_,
+                       client_address_);
+  clock_.AdvanceTime(QuicBufferedPacketStorePeer::expiration_alarm(&store_)
+                         ->deadline()
+                         .Subtract(clock_.ApproximateNow()));
+  alarm_factory_.FireAlarm(
+      QuicBufferedPacketStorePeer::expiration_alarm(&store_));
+  // |last_expired_packet_queue_| should be updated.
+  EXPECT_EQ(2u, visitor_.last_expired_packet_queue_.buffered_packets.size());
+}
+
+}  // namespace
+}  // namespace test
+}  // namespace net