blob: fa58bf517471d3c41717b7449f01cf3411820648 [file] [log] [blame]
/*
* Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#include <memory>
#include "webrtc/test/gmock.h"
#include "webrtc/test/gtest.h"
#include "webrtc/call.h"
#include "webrtc/system_wrappers/include/clock.h"
#include "webrtc/test/fake_network_pipe.h"
using ::testing::_;
using ::testing::AnyNumber;
using ::testing::Return;
using ::testing::Invoke;
namespace webrtc {
class TestReceiver : public PacketReceiver {
public:
TestReceiver() {}
virtual ~TestReceiver() {}
void IncomingPacket(const uint8_t* data, size_t length) {
DeliverPacket(MediaType::ANY, data, length, PacketTime());
delete [] data;
}
virtual MOCK_METHOD4(
DeliverPacket,
DeliveryStatus(MediaType, const uint8_t*, size_t, const PacketTime&));
};
class ReorderTestReceiver : public TestReceiver {
public:
ReorderTestReceiver() {}
virtual ~ReorderTestReceiver() {}
DeliveryStatus DeliverPacket(MediaType media_type,
const uint8_t* packet,
size_t length,
const PacketTime& packet_time) override {
int seq_num;
memcpy(&seq_num, packet, sizeof(int));
delivered_sequence_numbers_.push_back(seq_num);
return PacketReceiver::DELIVERY_OK;
}
std::vector<int> delivered_sequence_numbers_;
};
class FakeNetworkPipeTest : public ::testing::Test {
public:
FakeNetworkPipeTest() : fake_clock_(12345) {}
protected:
virtual void SetUp() {
receiver_.reset(new TestReceiver());
ON_CALL(*receiver_, DeliverPacket(_, _, _, _))
.WillByDefault(Return(PacketReceiver::DELIVERY_OK));
}
virtual void TearDown() {
}
void SendPackets(FakeNetworkPipe* pipe, int number_packets, int packet_size) {
RTC_DCHECK_GE(packet_size, static_cast<int>(sizeof(int)));
std::unique_ptr<uint8_t[]> packet(new uint8_t[packet_size]);
for (int i = 0; i < number_packets; ++i) {
// Set a sequence number for the packets by
// using the first bytes in the packet.
memcpy(packet.get(), &i, sizeof(int));
pipe->SendPacket(packet.get(), packet_size);
}
}
int PacketTimeMs(int capacity_kbps, int packet_size) const {
return 8 * packet_size / capacity_kbps;
}
SimulatedClock fake_clock_;
std::unique_ptr<TestReceiver> receiver_;
};
void DeleteMemory(uint8_t* data, int length) { delete [] data; }
// Test the capacity link and verify we get as many packets as we expect.
TEST_F(FakeNetworkPipeTest, CapacityTest) {
FakeNetworkPipe::Config config;
config.queue_length_packets = 20;
config.link_capacity_kbps = 80;
std::unique_ptr<FakeNetworkPipe> pipe(
new FakeNetworkPipe(&fake_clock_, config));
pipe->SetReceiver(receiver_.get());
// Add 10 packets of 1000 bytes, = 80 kb, and verify it takes one second to
// get through the pipe.
const int kNumPackets = 10;
const int kPacketSize = 1000;
SendPackets(pipe.get(), kNumPackets , kPacketSize);
// Time to get one packet through the link.
const int kPacketTimeMs = PacketTimeMs(config.link_capacity_kbps,
kPacketSize);
// Time haven't increased yet, so we souldn't get any packets.
EXPECT_CALL(*receiver_, DeliverPacket(_, _, _, _)).Times(0);
pipe->Process();
// Advance enough time to release one packet.
fake_clock_.AdvanceTimeMilliseconds(kPacketTimeMs);
EXPECT_CALL(*receiver_, DeliverPacket(_, _, _, _)).Times(1);
pipe->Process();
// Release all but one packet
fake_clock_.AdvanceTimeMilliseconds(9 * kPacketTimeMs - 1);
EXPECT_CALL(*receiver_, DeliverPacket(_, _, _, _)).Times(8);
pipe->Process();
// And the last one.
fake_clock_.AdvanceTimeMilliseconds(1);
EXPECT_CALL(*receiver_, DeliverPacket(_, _, _, _)).Times(1);
pipe->Process();
}
// Test the extra network delay.
TEST_F(FakeNetworkPipeTest, ExtraDelayTest) {
FakeNetworkPipe::Config config;
config.queue_length_packets = 20;
config.queue_delay_ms = 100;
config.link_capacity_kbps = 80;
std::unique_ptr<FakeNetworkPipe> pipe(
new FakeNetworkPipe(&fake_clock_, config));
pipe->SetReceiver(receiver_.get());
const int kNumPackets = 2;
const int kPacketSize = 1000;
SendPackets(pipe.get(), kNumPackets , kPacketSize);
// Time to get one packet through the link.
const int kPacketTimeMs = PacketTimeMs(config.link_capacity_kbps,
kPacketSize);
// Increase more than kPacketTimeMs, but not more than the extra delay.
fake_clock_.AdvanceTimeMilliseconds(kPacketTimeMs);
EXPECT_CALL(*receiver_, DeliverPacket(_, _, _, _)).Times(0);
pipe->Process();
// Advance the network delay to get the first packet.
fake_clock_.AdvanceTimeMilliseconds(config.queue_delay_ms);
EXPECT_CALL(*receiver_, DeliverPacket(_, _, _, _)).Times(1);
pipe->Process();
// Advance one more kPacketTimeMs to get the last packet.
fake_clock_.AdvanceTimeMilliseconds(kPacketTimeMs);
EXPECT_CALL(*receiver_, DeliverPacket(_, _, _, _)).Times(1);
pipe->Process();
}
// Test the number of buffers and packets are dropped when sending too many
// packets too quickly.
TEST_F(FakeNetworkPipeTest, QueueLengthTest) {
FakeNetworkPipe::Config config;
config.queue_length_packets = 2;
config.link_capacity_kbps = 80;
std::unique_ptr<FakeNetworkPipe> pipe(
new FakeNetworkPipe(&fake_clock_, config));
pipe->SetReceiver(receiver_.get());
const int kPacketSize = 1000;
const int kPacketTimeMs = PacketTimeMs(config.link_capacity_kbps,
kPacketSize);
// Send three packets and verify only 2 are delivered.
SendPackets(pipe.get(), 3, kPacketSize);
// Increase time enough to deliver all three packets, verify only two are
// delivered.
fake_clock_.AdvanceTimeMilliseconds(3 * kPacketTimeMs);
EXPECT_CALL(*receiver_, DeliverPacket(_, _, _, _)).Times(2);
pipe->Process();
}
// Test we get statistics as expected.
TEST_F(FakeNetworkPipeTest, StatisticsTest) {
FakeNetworkPipe::Config config;
config.queue_length_packets = 2;
config.queue_delay_ms = 20;
config.link_capacity_kbps = 80;
std::unique_ptr<FakeNetworkPipe> pipe(
new FakeNetworkPipe(&fake_clock_, config));
pipe->SetReceiver(receiver_.get());
const int kPacketSize = 1000;
const int kPacketTimeMs = PacketTimeMs(config.link_capacity_kbps,
kPacketSize);
// Send three packets and verify only 2 are delivered.
SendPackets(pipe.get(), 3, kPacketSize);
fake_clock_.AdvanceTimeMilliseconds(3 * kPacketTimeMs +
config.queue_delay_ms);
EXPECT_CALL(*receiver_, DeliverPacket(_, _, _, _)).Times(2);
pipe->Process();
// Packet 1: kPacketTimeMs + config.queue_delay_ms,
// packet 2: 2 * kPacketTimeMs + config.queue_delay_ms => 170 ms average.
EXPECT_EQ(pipe->AverageDelay(), 170);
EXPECT_EQ(pipe->sent_packets(), 2u);
EXPECT_EQ(pipe->dropped_packets(), 1u);
EXPECT_EQ(pipe->PercentageLoss(), 1/3.f);
}
// Change the link capacity half-way through the test and verify that the
// delivery times change accordingly.
TEST_F(FakeNetworkPipeTest, ChangingCapacityWithEmptyPipeTest) {
FakeNetworkPipe::Config config;
config.queue_length_packets = 20;
config.link_capacity_kbps = 80;
std::unique_ptr<FakeNetworkPipe> pipe(
new FakeNetworkPipe(&fake_clock_, config));
pipe->SetReceiver(receiver_.get());
// Add 10 packets of 1000 bytes, = 80 kb, and verify it takes one second to
// get through the pipe.
const int kNumPackets = 10;
const int kPacketSize = 1000;
SendPackets(pipe.get(), kNumPackets, kPacketSize);
// Time to get one packet through the link.
int packet_time_ms = PacketTimeMs(config.link_capacity_kbps, kPacketSize);
// Time hasn't increased yet, so we souldn't get any packets.
EXPECT_CALL(*receiver_, DeliverPacket(_, _, _, _)).Times(0);
pipe->Process();
// Advance time in steps to release one packet at a time.
for (int i = 0; i < kNumPackets; ++i) {
fake_clock_.AdvanceTimeMilliseconds(packet_time_ms);
EXPECT_CALL(*receiver_, DeliverPacket(_, _, _, _)).Times(1);
pipe->Process();
}
// Change the capacity.
config.link_capacity_kbps /= 2; // Reduce to 50%.
pipe->SetConfig(config);
// Add another 10 packets of 1000 bytes, = 80 kb, and verify it takes two
// seconds to get them through the pipe.
SendPackets(pipe.get(), kNumPackets, kPacketSize);
// Time to get one packet through the link.
packet_time_ms = PacketTimeMs(config.link_capacity_kbps, kPacketSize);
// Time hasn't increased yet, so we souldn't get any packets.
EXPECT_CALL(*receiver_, DeliverPacket(_, _, _, _)).Times(0);
pipe->Process();
// Advance time in steps to release one packet at a time.
for (int i = 0; i < kNumPackets; ++i) {
fake_clock_.AdvanceTimeMilliseconds(packet_time_ms);
EXPECT_CALL(*receiver_, DeliverPacket(_, _, _, _)).Times(1);
pipe->Process();
}
// Check that all the packets were sent.
EXPECT_EQ(static_cast<size_t>(2 * kNumPackets), pipe->sent_packets());
fake_clock_.AdvanceTimeMilliseconds(pipe->TimeUntilNextProcess());
EXPECT_CALL(*receiver_, DeliverPacket(_, _, _, _)).Times(0);
pipe->Process();
}
// Change the link capacity half-way through the test and verify that the
// delivery times change accordingly.
TEST_F(FakeNetworkPipeTest, ChangingCapacityWithPacketsInPipeTest) {
FakeNetworkPipe::Config config;
config.queue_length_packets = 20;
config.link_capacity_kbps = 80;
std::unique_ptr<FakeNetworkPipe> pipe(
new FakeNetworkPipe(&fake_clock_, config));
pipe->SetReceiver(receiver_.get());
// Add 10 packets of 1000 bytes, = 80 kb.
const int kNumPackets = 10;
const int kPacketSize = 1000;
SendPackets(pipe.get(), kNumPackets, kPacketSize);
// Time to get one packet through the link at the initial speed.
int packet_time_1_ms = PacketTimeMs(config.link_capacity_kbps, kPacketSize);
// Change the capacity.
config.link_capacity_kbps *= 2; // Double the capacity.
pipe->SetConfig(config);
// Add another 10 packets of 1000 bytes, = 80 kb, and verify it takes two
// seconds to get them through the pipe.
SendPackets(pipe.get(), kNumPackets, kPacketSize);
// Time to get one packet through the link at the new capacity.
int packet_time_2_ms = PacketTimeMs(config.link_capacity_kbps, kPacketSize);
// Time hasn't increased yet, so we souldn't get any packets.
EXPECT_CALL(*receiver_, DeliverPacket(_, _, _, _)).Times(0);
pipe->Process();
// Advance time in steps to release one packet at a time.
for (int i = 0; i < kNumPackets; ++i) {
fake_clock_.AdvanceTimeMilliseconds(packet_time_1_ms);
EXPECT_CALL(*receiver_, DeliverPacket(_, _, _, _)).Times(1);
pipe->Process();
}
// Advance time in steps to release one packet at a time.
for (int i = 0; i < kNumPackets; ++i) {
fake_clock_.AdvanceTimeMilliseconds(packet_time_2_ms);
EXPECT_CALL(*receiver_, DeliverPacket(_, _, _, _)).Times(1);
pipe->Process();
}
// Check that all the packets were sent.
EXPECT_EQ(static_cast<size_t>(2 * kNumPackets), pipe->sent_packets());
fake_clock_.AdvanceTimeMilliseconds(pipe->TimeUntilNextProcess());
EXPECT_CALL(*receiver_, DeliverPacket(_, _, _, _)).Times(0);
pipe->Process();
}
// At first disallow reordering and then allow reordering.
TEST_F(FakeNetworkPipeTest, DisallowReorderingThenAllowReordering) {
FakeNetworkPipe::Config config;
config.queue_length_packets = 1000;
config.link_capacity_kbps = 800;
config.queue_delay_ms = 100;
config.delay_standard_deviation_ms = 10;
std::unique_ptr<FakeNetworkPipe> pipe(
new FakeNetworkPipe(&fake_clock_, config));
ReorderTestReceiver* receiver = new ReorderTestReceiver();
receiver_.reset(receiver);
pipe->SetReceiver(receiver_.get());
const uint32_t kNumPackets = 100;
const int kPacketSize = 10;
SendPackets(pipe.get(), kNumPackets, kPacketSize);
fake_clock_.AdvanceTimeMilliseconds(1000);
pipe->Process();
// Confirm that all packets have been delivered in order.
EXPECT_EQ(kNumPackets, receiver->delivered_sequence_numbers_.size());
int last_seq_num = -1;
for (int seq_num : receiver->delivered_sequence_numbers_) {
EXPECT_GT(seq_num, last_seq_num);
last_seq_num = seq_num;
}
config.allow_reordering = true;
pipe->SetConfig(config);
SendPackets(pipe.get(), kNumPackets, kPacketSize);
fake_clock_.AdvanceTimeMilliseconds(1000);
receiver->delivered_sequence_numbers_.clear();
pipe->Process();
// Confirm that all packets have been delivered
// and that reordering has occured.
EXPECT_EQ(kNumPackets, receiver->delivered_sequence_numbers_.size());
bool reordering_has_occured = false;
last_seq_num = -1;
for (int seq_num : receiver->delivered_sequence_numbers_) {
if (last_seq_num > seq_num) {
reordering_has_occured = true;
break;
}
last_seq_num = seq_num;
}
EXPECT_TRUE(reordering_has_occured);
}
TEST_F(FakeNetworkPipeTest, BurstLoss) {
const int kLossPercent = 5;
const int kAvgBurstLength = 3;
const int kNumPackets = 10000;
const int kPacketSize = 10;
FakeNetworkPipe::Config config;
config.queue_length_packets = kNumPackets;
config.loss_percent = kLossPercent;
config.avg_burst_loss_length = kAvgBurstLength;
std::unique_ptr<FakeNetworkPipe> pipe(
new FakeNetworkPipe(&fake_clock_, config));
ReorderTestReceiver* receiver = new ReorderTestReceiver();
receiver_.reset(receiver);
pipe->SetReceiver(receiver_.get());
SendPackets(pipe.get(), kNumPackets, kPacketSize);
fake_clock_.AdvanceTimeMilliseconds(1000);
pipe->Process();
// Check that the average loss is |kLossPercent| percent.
int lost_packets = kNumPackets - receiver->delivered_sequence_numbers_.size();
double loss_fraction = lost_packets / static_cast<double>(kNumPackets);
EXPECT_NEAR(kLossPercent / 100.0, loss_fraction, 0.05);
// Find the number of bursts that has occurred.
size_t received_packets = receiver->delivered_sequence_numbers_.size();
int num_bursts = 0;
for (size_t i = 0; i < received_packets - 1; ++i) {
int diff = receiver->delivered_sequence_numbers_[i + 1] -
receiver->delivered_sequence_numbers_[i];
if (diff > 1)
++num_bursts;
}
double average_burst_length = static_cast<double>(lost_packets) / num_bursts;
EXPECT_NEAR(kAvgBurstLength, average_burst_length, 0.3);
}
} // namespace webrtc