|  | /* | 
|  | *  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 <list> | 
|  | #include <memory> | 
|  |  | 
|  | #include "webrtc/modules/pacing/paced_sender.h" | 
|  | #include "webrtc/system_wrappers/include/clock.h" | 
|  | #include "webrtc/test/gmock.h" | 
|  | #include "webrtc/test/gtest.h" | 
|  |  | 
|  | using testing::_; | 
|  | using testing::Field; | 
|  | using testing::Return; | 
|  |  | 
|  | namespace { | 
|  | constexpr unsigned kFirstClusterBps = 900000; | 
|  | constexpr unsigned kSecondClusterBps = 1800000; | 
|  |  | 
|  | // The error stems from truncating the time interval of probe packets to integer | 
|  | // values. This results in probing slightly higher than the target bitrate. | 
|  | // For 1.8 Mbps, this comes to be about 120 kbps with 1200 probe packets. | 
|  | constexpr int kBitrateProbingError = 150000; | 
|  | }  // namespace | 
|  |  | 
|  | namespace webrtc { | 
|  | namespace test { | 
|  |  | 
|  | static const int kTargetBitrateBps = 800000; | 
|  |  | 
|  | class MockPacedSenderCallback : public PacedSender::PacketSender { | 
|  | public: | 
|  | MOCK_METHOD5(TimeToSendPacket, | 
|  | bool(uint32_t ssrc, | 
|  | uint16_t sequence_number, | 
|  | int64_t capture_time_ms, | 
|  | bool retransmission, | 
|  | const PacedPacketInfo& pacing_info)); | 
|  | MOCK_METHOD2(TimeToSendPadding, | 
|  | size_t(size_t bytes, const PacedPacketInfo& pacing_info)); | 
|  | }; | 
|  |  | 
|  | class PacedSenderPadding : public PacedSender::PacketSender { | 
|  | public: | 
|  | PacedSenderPadding() : padding_sent_(0) {} | 
|  |  | 
|  | bool TimeToSendPacket(uint32_t ssrc, | 
|  | uint16_t sequence_number, | 
|  | int64_t capture_time_ms, | 
|  | bool retransmission, | 
|  | const PacedPacketInfo& pacing_info) override { | 
|  | return true; | 
|  | } | 
|  |  | 
|  | size_t TimeToSendPadding(size_t bytes, | 
|  | const PacedPacketInfo& pacing_info) override { | 
|  | const size_t kPaddingPacketSize = 224; | 
|  | size_t num_packets = (bytes + kPaddingPacketSize - 1) / kPaddingPacketSize; | 
|  | padding_sent_ += kPaddingPacketSize * num_packets; | 
|  | return kPaddingPacketSize * num_packets; | 
|  | } | 
|  |  | 
|  | size_t padding_sent() { return padding_sent_; } | 
|  |  | 
|  | private: | 
|  | size_t padding_sent_; | 
|  | }; | 
|  |  | 
|  | class PacedSenderProbing : public PacedSender::PacketSender { | 
|  | public: | 
|  | PacedSenderProbing() : packets_sent_(0), padding_sent_(0) {} | 
|  |  | 
|  | bool TimeToSendPacket(uint32_t ssrc, | 
|  | uint16_t sequence_number, | 
|  | int64_t capture_time_ms, | 
|  | bool retransmission, | 
|  | const PacedPacketInfo& pacing_info) override { | 
|  | packets_sent_++; | 
|  | return true; | 
|  | } | 
|  |  | 
|  | size_t TimeToSendPadding(size_t bytes, | 
|  | const PacedPacketInfo& pacing_info) override { | 
|  | padding_sent_ += bytes; | 
|  | return padding_sent_; | 
|  | } | 
|  |  | 
|  | int packets_sent() const { return packets_sent_; } | 
|  |  | 
|  | int padding_sent() const { return padding_sent_; } | 
|  |  | 
|  | private: | 
|  | int packets_sent_; | 
|  | int padding_sent_; | 
|  | }; | 
|  |  | 
|  | class PacedSenderTest : public ::testing::Test { | 
|  | protected: | 
|  | PacedSenderTest() : clock_(123456) { | 
|  | srand(0); | 
|  | // Need to initialize PacedSender after we initialize clock. | 
|  | send_bucket_.reset(new PacedSender(&clock_, &callback_, nullptr)); | 
|  | send_bucket_->CreateProbeCluster(kFirstClusterBps); | 
|  | send_bucket_->CreateProbeCluster(kSecondClusterBps); | 
|  | // Default to bitrate probing disabled for testing purposes. Probing tests | 
|  | // have to enable probing, either by creating a new PacedSender instance or | 
|  | // by calling SetProbingEnabled(true). | 
|  | send_bucket_->SetProbingEnabled(false); | 
|  | send_bucket_->SetEstimatedBitrate(kTargetBitrateBps); | 
|  |  | 
|  | clock_.AdvanceTimeMilliseconds(send_bucket_->TimeUntilNextProcess()); | 
|  | } | 
|  |  | 
|  | void SendAndExpectPacket(PacedSender::Priority priority, | 
|  | uint32_t ssrc, | 
|  | uint16_t sequence_number, | 
|  | int64_t capture_time_ms, | 
|  | size_t size, | 
|  | bool retransmission) { | 
|  | send_bucket_->InsertPacket(priority, ssrc, sequence_number, capture_time_ms, | 
|  | size, retransmission); | 
|  | EXPECT_CALL(callback_, TimeToSendPacket(ssrc, sequence_number, | 
|  | capture_time_ms, retransmission, _)) | 
|  | .Times(1) | 
|  | .WillRepeatedly(Return(true)); | 
|  | } | 
|  | SimulatedClock clock_; | 
|  | MockPacedSenderCallback callback_; | 
|  | std::unique_ptr<PacedSender> send_bucket_; | 
|  | }; | 
|  |  | 
|  | TEST_F(PacedSenderTest, FirstSentPacketTimeIsSet) { | 
|  | uint16_t sequence_number = 1234; | 
|  | const uint32_t kSsrc = 12345; | 
|  | const size_t kSizeBytes = 250; | 
|  | const size_t kPacketToSend = 3; | 
|  | const int64_t kStartMs = clock_.TimeInMilliseconds(); | 
|  |  | 
|  | // No packet sent. | 
|  | EXPECT_EQ(-1, send_bucket_->FirstSentPacketTimeMs()); | 
|  |  | 
|  | for (size_t i = 0; i < kPacketToSend; ++i) { | 
|  | SendAndExpectPacket(PacedSender::kNormalPriority, kSsrc, sequence_number++, | 
|  | clock_.TimeInMilliseconds(), kSizeBytes, false); | 
|  | send_bucket_->Process(); | 
|  | clock_.AdvanceTimeMilliseconds(send_bucket_->TimeUntilNextProcess()); | 
|  | } | 
|  | EXPECT_EQ(kStartMs, send_bucket_->FirstSentPacketTimeMs()); | 
|  | } | 
|  |  | 
|  | TEST_F(PacedSenderTest, QueuePacket) { | 
|  | uint32_t ssrc = 12345; | 
|  | uint16_t sequence_number = 1234; | 
|  | // Due to the multiplicative factor we can send 5 packets during a send | 
|  | // interval. (network capacity * multiplier / (8 bits per byte * | 
|  | // (packet size * #send intervals per second) | 
|  | const size_t packets_to_send = | 
|  | kTargetBitrateBps * PacedSender::kDefaultPaceMultiplier / (8 * 250 * 200); | 
|  | for (size_t i = 0; i < packets_to_send; ++i) { | 
|  | SendAndExpectPacket(PacedSender::kNormalPriority, ssrc, sequence_number++, | 
|  | clock_.TimeInMilliseconds(), 250, false); | 
|  | } | 
|  |  | 
|  | int64_t queued_packet_timestamp = clock_.TimeInMilliseconds(); | 
|  | send_bucket_->InsertPacket(PacedSender::kNormalPriority, ssrc, | 
|  | sequence_number, queued_packet_timestamp, 250, | 
|  | false); | 
|  | EXPECT_EQ(packets_to_send + 1, send_bucket_->QueueSizePackets()); | 
|  | send_bucket_->Process(); | 
|  | EXPECT_EQ(5, send_bucket_->TimeUntilNextProcess()); | 
|  | EXPECT_CALL(callback_, TimeToSendPadding(_, _)).Times(0); | 
|  | clock_.AdvanceTimeMilliseconds(4); | 
|  | EXPECT_EQ(1, send_bucket_->TimeUntilNextProcess()); | 
|  | clock_.AdvanceTimeMilliseconds(1); | 
|  | EXPECT_EQ(0, send_bucket_->TimeUntilNextProcess()); | 
|  | EXPECT_EQ(1u, send_bucket_->QueueSizePackets()); | 
|  | EXPECT_CALL(callback_, TimeToSendPacket(ssrc, sequence_number++, | 
|  | queued_packet_timestamp, false, _)) | 
|  | .Times(1) | 
|  | .WillRepeatedly(Return(true)); | 
|  | send_bucket_->Process(); | 
|  | sequence_number++; | 
|  | EXPECT_EQ(0u, send_bucket_->QueueSizePackets()); | 
|  |  | 
|  | // We can send packets_to_send -1 packets of size 250 during the current | 
|  | // interval since one packet has already been sent. | 
|  | for (size_t i = 0; i < packets_to_send - 1; ++i) { | 
|  | SendAndExpectPacket(PacedSender::kNormalPriority, ssrc, sequence_number++, | 
|  | clock_.TimeInMilliseconds(), 250, false); | 
|  | } | 
|  | send_bucket_->InsertPacket(PacedSender::kNormalPriority, ssrc, | 
|  | sequence_number++, clock_.TimeInMilliseconds(), | 
|  | 250, false); | 
|  | EXPECT_EQ(packets_to_send, send_bucket_->QueueSizePackets()); | 
|  | send_bucket_->Process(); | 
|  | EXPECT_EQ(1u, send_bucket_->QueueSizePackets()); | 
|  | } | 
|  |  | 
|  | TEST_F(PacedSenderTest, PaceQueuedPackets) { | 
|  | uint32_t ssrc = 12345; | 
|  | uint16_t sequence_number = 1234; | 
|  |  | 
|  | // Due to the multiplicative factor we can send 5 packets during a send | 
|  | // interval. (network capacity * multiplier / (8 bits per byte * | 
|  | // (packet size * #send intervals per second) | 
|  | const size_t packets_to_send_per_interval = | 
|  | kTargetBitrateBps * PacedSender::kDefaultPaceMultiplier / (8 * 250 * 200); | 
|  | for (size_t i = 0; i < packets_to_send_per_interval; ++i) { | 
|  | SendAndExpectPacket(PacedSender::kNormalPriority, ssrc, sequence_number++, | 
|  | clock_.TimeInMilliseconds(), 250, false); | 
|  | } | 
|  |  | 
|  | for (size_t j = 0; j < packets_to_send_per_interval * 10; ++j) { | 
|  | send_bucket_->InsertPacket(PacedSender::kNormalPriority, ssrc, | 
|  | sequence_number++, clock_.TimeInMilliseconds(), | 
|  | 250, false); | 
|  | } | 
|  | EXPECT_EQ(packets_to_send_per_interval + packets_to_send_per_interval * 10, | 
|  | send_bucket_->QueueSizePackets()); | 
|  | send_bucket_->Process(); | 
|  | EXPECT_EQ(packets_to_send_per_interval * 10, | 
|  | send_bucket_->QueueSizePackets()); | 
|  | EXPECT_CALL(callback_, TimeToSendPadding(_, _)).Times(0); | 
|  | for (int k = 0; k < 10; ++k) { | 
|  | EXPECT_EQ(5, send_bucket_->TimeUntilNextProcess()); | 
|  | clock_.AdvanceTimeMilliseconds(5); | 
|  | EXPECT_CALL(callback_, TimeToSendPacket(ssrc, _, _, false, _)) | 
|  | .Times(packets_to_send_per_interval) | 
|  | .WillRepeatedly(Return(true)); | 
|  | EXPECT_EQ(0, send_bucket_->TimeUntilNextProcess()); | 
|  | send_bucket_->Process(); | 
|  | } | 
|  | EXPECT_EQ(0u, send_bucket_->QueueSizePackets()); | 
|  | EXPECT_EQ(5, send_bucket_->TimeUntilNextProcess()); | 
|  | clock_.AdvanceTimeMilliseconds(5); | 
|  | EXPECT_EQ(0, send_bucket_->TimeUntilNextProcess()); | 
|  | EXPECT_EQ(0u, send_bucket_->QueueSizePackets()); | 
|  | send_bucket_->Process(); | 
|  |  | 
|  | for (size_t i = 0; i < packets_to_send_per_interval; ++i) { | 
|  | SendAndExpectPacket(PacedSender::kNormalPriority, ssrc, sequence_number++, | 
|  | clock_.TimeInMilliseconds(), 250, false); | 
|  | } | 
|  | send_bucket_->InsertPacket(PacedSender::kNormalPriority, ssrc, | 
|  | sequence_number, clock_.TimeInMilliseconds(), 250, | 
|  | false); | 
|  | send_bucket_->Process(); | 
|  | EXPECT_EQ(1u, send_bucket_->QueueSizePackets()); | 
|  | } | 
|  |  | 
|  | TEST_F(PacedSenderTest, PaceQueuedPacketsWithDuplicates) { | 
|  | uint32_t ssrc = 12345; | 
|  | uint16_t sequence_number = 1234; | 
|  | uint16_t queued_sequence_number; | 
|  |  | 
|  | // Due to the multiplicative factor we can send 5 packets during a send | 
|  | // interval. (network capacity * multiplier / (8 bits per byte * | 
|  | // (packet size * #send intervals per second) | 
|  | const size_t packets_to_send_per_interval = | 
|  | kTargetBitrateBps * PacedSender::kDefaultPaceMultiplier / (8 * 250 * 200); | 
|  | for (size_t i = 0; i < packets_to_send_per_interval; ++i) { | 
|  | SendAndExpectPacket(PacedSender::kNormalPriority, ssrc, sequence_number++, | 
|  | clock_.TimeInMilliseconds(), 250, false); | 
|  | } | 
|  | queued_sequence_number = sequence_number; | 
|  |  | 
|  | for (size_t j = 0; j < packets_to_send_per_interval * 10; ++j) { | 
|  | // Send in duplicate packets. | 
|  | send_bucket_->InsertPacket(PacedSender::kNormalPriority, ssrc, | 
|  | sequence_number, clock_.TimeInMilliseconds(), | 
|  | 250, false); | 
|  | send_bucket_->InsertPacket(PacedSender::kNormalPriority, ssrc, | 
|  | sequence_number++, clock_.TimeInMilliseconds(), | 
|  | 250, false); | 
|  | } | 
|  | EXPECT_CALL(callback_, TimeToSendPadding(_, _)).Times(0); | 
|  | send_bucket_->Process(); | 
|  | for (int k = 0; k < 10; ++k) { | 
|  | EXPECT_EQ(5, send_bucket_->TimeUntilNextProcess()); | 
|  | clock_.AdvanceTimeMilliseconds(5); | 
|  |  | 
|  | for (size_t i = 0; i < packets_to_send_per_interval; ++i) { | 
|  | EXPECT_CALL(callback_, | 
|  | TimeToSendPacket(ssrc, queued_sequence_number++, _, false, _)) | 
|  | .Times(1) | 
|  | .WillRepeatedly(Return(true)); | 
|  | } | 
|  | EXPECT_EQ(0, send_bucket_->TimeUntilNextProcess()); | 
|  | send_bucket_->Process(); | 
|  | } | 
|  | EXPECT_EQ(5, send_bucket_->TimeUntilNextProcess()); | 
|  | clock_.AdvanceTimeMilliseconds(5); | 
|  | EXPECT_EQ(0, send_bucket_->TimeUntilNextProcess()); | 
|  | send_bucket_->Process(); | 
|  |  | 
|  | for (size_t i = 0; i < packets_to_send_per_interval; ++i) { | 
|  | SendAndExpectPacket(PacedSender::kNormalPriority, ssrc, sequence_number++, | 
|  | clock_.TimeInMilliseconds(), 250, false); | 
|  | } | 
|  | send_bucket_->InsertPacket(PacedSender::kNormalPriority, ssrc, | 
|  | sequence_number++, clock_.TimeInMilliseconds(), | 
|  | 250, false); | 
|  | send_bucket_->Process(); | 
|  | EXPECT_EQ(1u, send_bucket_->QueueSizePackets()); | 
|  | } | 
|  |  | 
|  | TEST_F(PacedSenderTest, CanQueuePacketsWithSameSequenceNumberOnDifferentSsrcs) { | 
|  | uint32_t ssrc = 12345; | 
|  | uint16_t sequence_number = 1234; | 
|  |  | 
|  | SendAndExpectPacket(PacedSender::kNormalPriority, | 
|  | ssrc, | 
|  | sequence_number, | 
|  | clock_.TimeInMilliseconds(), | 
|  | 250, | 
|  | false); | 
|  |  | 
|  | // Expect packet on second ssrc to be queued and sent as well. | 
|  | SendAndExpectPacket(PacedSender::kNormalPriority, | 
|  | ssrc + 1, | 
|  | sequence_number, | 
|  | clock_.TimeInMilliseconds(), | 
|  | 250, | 
|  | false); | 
|  |  | 
|  | clock_.AdvanceTimeMilliseconds(1000); | 
|  | send_bucket_->Process(); | 
|  | } | 
|  |  | 
|  | TEST_F(PacedSenderTest, Padding) { | 
|  | uint32_t ssrc = 12345; | 
|  | uint16_t sequence_number = 1234; | 
|  |  | 
|  | send_bucket_->SetEstimatedBitrate(kTargetBitrateBps); | 
|  | send_bucket_->SetSendBitrateLimits(kTargetBitrateBps, kTargetBitrateBps); | 
|  |  | 
|  | // Due to the multiplicative factor we can send 5 packets during a send | 
|  | // interval. (network capacity * multiplier / (8 bits per byte * | 
|  | // (packet size * #send intervals per second) | 
|  | const size_t packets_to_send_per_interval = | 
|  | kTargetBitrateBps * PacedSender::kDefaultPaceMultiplier / (8 * 250 * 200); | 
|  | for (size_t i = 0; i < packets_to_send_per_interval; ++i) { | 
|  | SendAndExpectPacket(PacedSender::kNormalPriority, ssrc, sequence_number++, | 
|  | clock_.TimeInMilliseconds(), 250, false); | 
|  | } | 
|  | // No padding is expected since we have sent too much already. | 
|  | EXPECT_CALL(callback_, TimeToSendPadding(_, _)).Times(0); | 
|  | EXPECT_EQ(0, send_bucket_->TimeUntilNextProcess()); | 
|  | send_bucket_->Process(); | 
|  | EXPECT_EQ(0u, send_bucket_->QueueSizePackets()); | 
|  |  | 
|  | // 5 milliseconds later should not send padding since we filled the buffers | 
|  | // initially. | 
|  | EXPECT_CALL(callback_, TimeToSendPadding(250, _)).Times(0); | 
|  | EXPECT_EQ(5, send_bucket_->TimeUntilNextProcess()); | 
|  | clock_.AdvanceTimeMilliseconds(5); | 
|  | EXPECT_EQ(0, send_bucket_->TimeUntilNextProcess()); | 
|  | send_bucket_->Process(); | 
|  |  | 
|  | // 5 milliseconds later we have enough budget to send some padding. | 
|  | EXPECT_CALL(callback_, TimeToSendPadding(250, _)) | 
|  | .Times(1) | 
|  | .WillOnce(Return(250)); | 
|  | EXPECT_EQ(5, send_bucket_->TimeUntilNextProcess()); | 
|  | clock_.AdvanceTimeMilliseconds(5); | 
|  | EXPECT_EQ(0, send_bucket_->TimeUntilNextProcess()); | 
|  | send_bucket_->Process(); | 
|  | } | 
|  |  | 
|  | TEST_F(PacedSenderTest, NoPaddingBeforeNormalPacket) { | 
|  | send_bucket_->SetEstimatedBitrate(kTargetBitrateBps); | 
|  | send_bucket_->SetSendBitrateLimits(kTargetBitrateBps, kTargetBitrateBps); | 
|  |  | 
|  | EXPECT_CALL(callback_, TimeToSendPadding(_, _)).Times(0); | 
|  | send_bucket_->Process(); | 
|  | clock_.AdvanceTimeMilliseconds(send_bucket_->TimeUntilNextProcess()); | 
|  |  | 
|  | send_bucket_->Process(); | 
|  | clock_.AdvanceTimeMilliseconds(send_bucket_->TimeUntilNextProcess()); | 
|  |  | 
|  | uint32_t ssrc = 12345; | 
|  | uint16_t sequence_number = 1234; | 
|  | int64_t capture_time_ms = 56789; | 
|  |  | 
|  | SendAndExpectPacket(PacedSender::kNormalPriority, ssrc, sequence_number++, | 
|  | capture_time_ms, 250, false); | 
|  | EXPECT_CALL(callback_, TimeToSendPadding(250, _)) | 
|  | .Times(1) | 
|  | .WillOnce(Return(250)); | 
|  | send_bucket_->Process(); | 
|  | } | 
|  |  | 
|  | TEST_F(PacedSenderTest, VerifyPaddingUpToBitrate) { | 
|  | uint32_t ssrc = 12345; | 
|  | uint16_t sequence_number = 1234; | 
|  | int64_t capture_time_ms = 56789; | 
|  | const int kTimeStep = 5; | 
|  | const int64_t kBitrateWindow = 100; | 
|  | send_bucket_->SetEstimatedBitrate(kTargetBitrateBps); | 
|  | send_bucket_->SetSendBitrateLimits(kTargetBitrateBps, kTargetBitrateBps); | 
|  |  | 
|  | int64_t start_time = clock_.TimeInMilliseconds(); | 
|  | while (clock_.TimeInMilliseconds() - start_time < kBitrateWindow) { | 
|  | SendAndExpectPacket(PacedSender::kNormalPriority, | 
|  | ssrc, | 
|  | sequence_number++, | 
|  | capture_time_ms, | 
|  | 250, | 
|  | false); | 
|  | EXPECT_CALL(callback_, TimeToSendPadding(250, _)) | 
|  | .Times(1) | 
|  | .WillOnce(Return(250)); | 
|  | send_bucket_->Process(); | 
|  | clock_.AdvanceTimeMilliseconds(kTimeStep); | 
|  | } | 
|  | } | 
|  |  | 
|  | TEST_F(PacedSenderTest, VerifyAverageBitrateVaryingMediaPayload) { | 
|  | uint32_t ssrc = 12345; | 
|  | uint16_t sequence_number = 1234; | 
|  | int64_t capture_time_ms = 56789; | 
|  | const int kTimeStep = 5; | 
|  | const int64_t kBitrateWindow = 10000; | 
|  | PacedSenderPadding callback; | 
|  | send_bucket_.reset(new PacedSender(&clock_, &callback, nullptr)); | 
|  | send_bucket_->SetProbingEnabled(false); | 
|  | send_bucket_->SetEstimatedBitrate(kTargetBitrateBps); | 
|  |  | 
|  | send_bucket_->SetSendBitrateLimits( | 
|  | 0 /*allocated_bitrate_bps*/, | 
|  | kTargetBitrateBps * 2 /* max_padding_bitrate_bps */); | 
|  |  | 
|  | int64_t start_time = clock_.TimeInMilliseconds(); | 
|  | size_t media_bytes = 0; | 
|  | while (clock_.TimeInMilliseconds() - start_time < kBitrateWindow) { | 
|  | int rand_value = rand();  // NOLINT (rand_r instead of rand) | 
|  | size_t media_payload = rand_value % 100 + 200;  // [200, 300] bytes. | 
|  | send_bucket_->InsertPacket(PacedSender::kNormalPriority, ssrc, | 
|  | sequence_number++, capture_time_ms, | 
|  | media_payload, false); | 
|  | media_bytes += media_payload; | 
|  | clock_.AdvanceTimeMilliseconds(kTimeStep); | 
|  | send_bucket_->Process(); | 
|  | } | 
|  | EXPECT_NEAR(kTargetBitrateBps / 1000, | 
|  | static_cast<int>(8 * (media_bytes + callback.padding_sent()) / | 
|  | kBitrateWindow), | 
|  | 1); | 
|  | } | 
|  |  | 
|  | TEST_F(PacedSenderTest, Priority) { | 
|  | uint32_t ssrc_low_priority = 12345; | 
|  | uint32_t ssrc = 12346; | 
|  | uint16_t sequence_number = 1234; | 
|  | int64_t capture_time_ms = 56789; | 
|  | int64_t capture_time_ms_low_priority = 1234567; | 
|  |  | 
|  | // Due to the multiplicative factor we can send 5 packets during a send | 
|  | // interval. (network capacity * multiplier / (8 bits per byte * | 
|  | // (packet size * #send intervals per second) | 
|  | const size_t packets_to_send_per_interval = | 
|  | kTargetBitrateBps * PacedSender::kDefaultPaceMultiplier / (8 * 250 * 200); | 
|  | for (size_t i = 0; i < packets_to_send_per_interval; ++i) { | 
|  | SendAndExpectPacket(PacedSender::kNormalPriority, ssrc, sequence_number++, | 
|  | clock_.TimeInMilliseconds(), 250, false); | 
|  | } | 
|  | send_bucket_->Process(); | 
|  | EXPECT_EQ(0u, send_bucket_->QueueSizePackets()); | 
|  |  | 
|  | // Expect normal and low priority to be queued and high to pass through. | 
|  | send_bucket_->InsertPacket(PacedSender::kLowPriority, ssrc_low_priority, | 
|  | sequence_number++, capture_time_ms_low_priority, | 
|  | 250, false); | 
|  |  | 
|  | for (size_t i = 0; i < packets_to_send_per_interval; ++i) { | 
|  | send_bucket_->InsertPacket(PacedSender::kNormalPriority, ssrc, | 
|  | sequence_number++, capture_time_ms, 250, false); | 
|  | } | 
|  | send_bucket_->InsertPacket(PacedSender::kHighPriority, ssrc, | 
|  | sequence_number++, capture_time_ms, 250, false); | 
|  |  | 
|  | // Expect all high and normal priority to be sent out first. | 
|  | EXPECT_CALL(callback_, TimeToSendPadding(_, _)).Times(0); | 
|  | EXPECT_CALL(callback_, TimeToSendPacket(ssrc, _, capture_time_ms, false, _)) | 
|  | .Times(packets_to_send_per_interval + 1) | 
|  | .WillRepeatedly(Return(true)); | 
|  |  | 
|  | EXPECT_EQ(5, send_bucket_->TimeUntilNextProcess()); | 
|  | clock_.AdvanceTimeMilliseconds(5); | 
|  | EXPECT_EQ(0, send_bucket_->TimeUntilNextProcess()); | 
|  | send_bucket_->Process(); | 
|  | EXPECT_EQ(1u, send_bucket_->QueueSizePackets()); | 
|  |  | 
|  | EXPECT_CALL(callback_, | 
|  | TimeToSendPacket(ssrc_low_priority, _, | 
|  | capture_time_ms_low_priority, false, _)) | 
|  | .Times(1) | 
|  | .WillRepeatedly(Return(true)); | 
|  |  | 
|  | EXPECT_EQ(5, send_bucket_->TimeUntilNextProcess()); | 
|  | clock_.AdvanceTimeMilliseconds(5); | 
|  | EXPECT_EQ(0, send_bucket_->TimeUntilNextProcess()); | 
|  | send_bucket_->Process(); | 
|  | } | 
|  |  | 
|  | TEST_F(PacedSenderTest, RetransmissionPriority) { | 
|  | uint32_t ssrc = 12345; | 
|  | uint16_t sequence_number = 1234; | 
|  | int64_t capture_time_ms = 45678; | 
|  | int64_t capture_time_ms_retransmission = 56789; | 
|  |  | 
|  | // Due to the multiplicative factor we can send 5 packets during a send | 
|  | // interval. (network capacity * multiplier / (8 bits per byte * | 
|  | // (packet size * #send intervals per second) | 
|  | const size_t packets_to_send_per_interval = | 
|  | kTargetBitrateBps * PacedSender::kDefaultPaceMultiplier / (8 * 250 * 200); | 
|  | send_bucket_->Process(); | 
|  | EXPECT_EQ(0u, send_bucket_->QueueSizePackets()); | 
|  |  | 
|  | // Alternate retransmissions and normal packets. | 
|  | for (size_t i = 0; i < packets_to_send_per_interval; ++i) { | 
|  | send_bucket_->InsertPacket(PacedSender::kNormalPriority, ssrc, | 
|  | sequence_number++, | 
|  | capture_time_ms_retransmission, 250, true); | 
|  | send_bucket_->InsertPacket(PacedSender::kNormalPriority, ssrc, | 
|  | sequence_number++, capture_time_ms, 250, false); | 
|  | } | 
|  | EXPECT_EQ(2 * packets_to_send_per_interval, send_bucket_->QueueSizePackets()); | 
|  |  | 
|  | // Expect all retransmissions to be sent out first despite having a later | 
|  | // capture time. | 
|  | EXPECT_CALL(callback_, TimeToSendPadding(_, _)).Times(0); | 
|  | EXPECT_CALL(callback_, TimeToSendPacket(_, _, _, false, _)).Times(0); | 
|  | EXPECT_CALL(callback_, TimeToSendPacket( | 
|  | ssrc, _, capture_time_ms_retransmission, true, _)) | 
|  | .Times(packets_to_send_per_interval) | 
|  | .WillRepeatedly(Return(true)); | 
|  |  | 
|  | EXPECT_EQ(5, send_bucket_->TimeUntilNextProcess()); | 
|  | clock_.AdvanceTimeMilliseconds(5); | 
|  | EXPECT_EQ(0, send_bucket_->TimeUntilNextProcess()); | 
|  | send_bucket_->Process(); | 
|  | EXPECT_EQ(packets_to_send_per_interval, send_bucket_->QueueSizePackets()); | 
|  |  | 
|  | // Expect the remaining (non-retransmission) packets to be sent. | 
|  | EXPECT_CALL(callback_, TimeToSendPadding(_, _)).Times(0); | 
|  | EXPECT_CALL(callback_, TimeToSendPacket(_, _, _, true, _)).Times(0); | 
|  | EXPECT_CALL(callback_, TimeToSendPacket(ssrc, _, capture_time_ms, false, _)) | 
|  | .Times(packets_to_send_per_interval) | 
|  | .WillRepeatedly(Return(true)); | 
|  |  | 
|  | EXPECT_EQ(5, send_bucket_->TimeUntilNextProcess()); | 
|  | clock_.AdvanceTimeMilliseconds(5); | 
|  | EXPECT_EQ(0, send_bucket_->TimeUntilNextProcess()); | 
|  | send_bucket_->Process(); | 
|  |  | 
|  | EXPECT_EQ(0u, send_bucket_->QueueSizePackets()); | 
|  | } | 
|  |  | 
|  | TEST_F(PacedSenderTest, HighPrioDoesntAffectBudget) { | 
|  | uint32_t ssrc = 12346; | 
|  | uint16_t sequence_number = 1234; | 
|  | int64_t capture_time_ms = 56789; | 
|  |  | 
|  | // As high prio packets doesn't affect the budget, we should be able to send | 
|  | // a high number of them at once. | 
|  | for (int i = 0; i < 25; ++i) { | 
|  | SendAndExpectPacket(PacedSender::kHighPriority, ssrc, sequence_number++, | 
|  | capture_time_ms, 250, false); | 
|  | } | 
|  | send_bucket_->Process(); | 
|  | // Low prio packets does affect the budget. | 
|  | // Due to the multiplicative factor we can send 5 packets during a send | 
|  | // interval. (network capacity * multiplier / (8 bits per byte * | 
|  | // (packet size * #send intervals per second) | 
|  | const size_t packets_to_send_per_interval = | 
|  | kTargetBitrateBps * PacedSender::kDefaultPaceMultiplier / (8 * 250 * 200); | 
|  | for (size_t i = 0; i < packets_to_send_per_interval; ++i) { | 
|  | SendAndExpectPacket(PacedSender::kLowPriority, ssrc, sequence_number++, | 
|  | clock_.TimeInMilliseconds(), 250, false); | 
|  | } | 
|  | send_bucket_->InsertPacket(PacedSender::kLowPriority, ssrc, sequence_number, | 
|  | capture_time_ms, 250, false); | 
|  | EXPECT_EQ(5, send_bucket_->TimeUntilNextProcess()); | 
|  | clock_.AdvanceTimeMilliseconds(5); | 
|  | send_bucket_->Process(); | 
|  | EXPECT_EQ(1u, send_bucket_->QueueSizePackets()); | 
|  | EXPECT_CALL(callback_, TimeToSendPacket(ssrc, sequence_number++, | 
|  | capture_time_ms, false, _)) | 
|  | .Times(1) | 
|  | .WillRepeatedly(Return(true)); | 
|  | EXPECT_EQ(5, send_bucket_->TimeUntilNextProcess()); | 
|  | clock_.AdvanceTimeMilliseconds(5); | 
|  | send_bucket_->Process(); | 
|  | EXPECT_EQ(0u, send_bucket_->QueueSizePackets()); | 
|  | } | 
|  |  | 
|  | TEST_F(PacedSenderTest, Pause) { | 
|  | uint32_t ssrc_low_priority = 12345; | 
|  | uint32_t ssrc = 12346; | 
|  | uint32_t ssrc_high_priority = 12347; | 
|  | uint16_t sequence_number = 1234; | 
|  | int64_t capture_time_ms = clock_.TimeInMilliseconds(); | 
|  |  | 
|  | EXPECT_EQ(0, send_bucket_->QueueInMs()); | 
|  |  | 
|  | // Due to the multiplicative factor we can send 5 packets during a send | 
|  | // interval. (network capacity * multiplier / (8 bits per byte * | 
|  | // (packet size * #send intervals per second) | 
|  | const size_t packets_to_send_per_interval = | 
|  | kTargetBitrateBps * PacedSender::kDefaultPaceMultiplier / (8 * 250 * 200); | 
|  | for (size_t i = 0; i < packets_to_send_per_interval; ++i) { | 
|  | SendAndExpectPacket(PacedSender::kNormalPriority, ssrc, sequence_number++, | 
|  | clock_.TimeInMilliseconds(), 250, false); | 
|  | } | 
|  |  | 
|  | send_bucket_->Process(); | 
|  |  | 
|  | send_bucket_->Pause(); | 
|  |  | 
|  | for (size_t i = 0; i < packets_to_send_per_interval; ++i) { | 
|  | send_bucket_->InsertPacket(PacedSender::kLowPriority, ssrc_low_priority, | 
|  | sequence_number++, capture_time_ms, 250, false); | 
|  | send_bucket_->InsertPacket(PacedSender::kNormalPriority, ssrc, | 
|  | sequence_number++, capture_time_ms, 250, false); | 
|  | send_bucket_->InsertPacket(PacedSender::kHighPriority, ssrc_high_priority, | 
|  | sequence_number++, capture_time_ms, 250, false); | 
|  | } | 
|  | clock_.AdvanceTimeMilliseconds(10000); | 
|  | int64_t second_capture_time_ms = clock_.TimeInMilliseconds(); | 
|  | for (size_t i = 0; i < packets_to_send_per_interval; ++i) { | 
|  | send_bucket_->InsertPacket(PacedSender::kLowPriority, ssrc_low_priority, | 
|  | sequence_number++, second_capture_time_ms, 250, | 
|  | false); | 
|  | send_bucket_->InsertPacket(PacedSender::kNormalPriority, ssrc, | 
|  | sequence_number++, second_capture_time_ms, 250, | 
|  | false); | 
|  | send_bucket_->InsertPacket(PacedSender::kHighPriority, ssrc_high_priority, | 
|  | sequence_number++, second_capture_time_ms, 250, | 
|  | false); | 
|  | } | 
|  |  | 
|  | // Expect everything to be queued. | 
|  | EXPECT_EQ(second_capture_time_ms - capture_time_ms, | 
|  | send_bucket_->QueueInMs()); | 
|  |  | 
|  | for (int i = 0; i < 10; ++i) { | 
|  | clock_.AdvanceTimeMilliseconds(5); | 
|  | // TimeUntilNextProcess must not return 0 when paused.  If it does, | 
|  | // we risk running a busy loop, so ideally it should return a large value. | 
|  | EXPECT_GE(send_bucket_->TimeUntilNextProcess(), 1000); | 
|  | send_bucket_->Process(); | 
|  | } | 
|  |  | 
|  | // Expect high prio packets to come out first followed by normal | 
|  | // prio packets and low prio packets (all in capture order). | 
|  | { | 
|  | ::testing::InSequence sequence; | 
|  | EXPECT_CALL(callback_, | 
|  | TimeToSendPacket(ssrc_high_priority, _, capture_time_ms, _, _)) | 
|  | .Times(packets_to_send_per_interval) | 
|  | .WillRepeatedly(Return(true)); | 
|  | EXPECT_CALL(callback_, TimeToSendPacket(ssrc_high_priority, _, | 
|  | second_capture_time_ms, _, _)) | 
|  | .Times(packets_to_send_per_interval) | 
|  | .WillRepeatedly(Return(true)); | 
|  |  | 
|  | for (size_t i = 0; i < packets_to_send_per_interval; ++i) { | 
|  | EXPECT_CALL(callback_, TimeToSendPacket(ssrc, _, capture_time_ms, _, _)) | 
|  | .Times(1) | 
|  | .WillRepeatedly(Return(true)); | 
|  | } | 
|  | for (size_t i = 0; i < packets_to_send_per_interval; ++i) { | 
|  | EXPECT_CALL(callback_, | 
|  | TimeToSendPacket(ssrc, _, second_capture_time_ms, _, _)) | 
|  | .Times(1) | 
|  | .WillRepeatedly(Return(true)); | 
|  | } | 
|  | for (size_t i = 0; i < packets_to_send_per_interval; ++i) { | 
|  | EXPECT_CALL(callback_, | 
|  | TimeToSendPacket(ssrc_low_priority, _, capture_time_ms, _, _)) | 
|  | .Times(1) | 
|  | .WillRepeatedly(Return(true)); | 
|  | } | 
|  | for (size_t i = 0; i < packets_to_send_per_interval; ++i) { | 
|  | EXPECT_CALL(callback_, TimeToSendPacket(ssrc_low_priority, _, | 
|  | second_capture_time_ms, _, _)) | 
|  | .Times(1) | 
|  | .WillRepeatedly(Return(true)); | 
|  | } | 
|  | } | 
|  | send_bucket_->Resume(); | 
|  |  | 
|  | for (size_t i = 0; i < 4; i++) { | 
|  | EXPECT_EQ(5, send_bucket_->TimeUntilNextProcess()); | 
|  | clock_.AdvanceTimeMilliseconds(5); | 
|  | EXPECT_EQ(0, send_bucket_->TimeUntilNextProcess()); | 
|  | send_bucket_->Process(); | 
|  | } | 
|  |  | 
|  | EXPECT_EQ(0, send_bucket_->QueueInMs()); | 
|  | } | 
|  |  | 
|  | TEST_F(PacedSenderTest, ResendPacket) { | 
|  | uint32_t ssrc = 12346; | 
|  | uint16_t sequence_number = 1234; | 
|  | int64_t capture_time_ms = clock_.TimeInMilliseconds(); | 
|  | EXPECT_EQ(0, send_bucket_->QueueInMs()); | 
|  |  | 
|  | send_bucket_->InsertPacket(PacedSender::kNormalPriority, ssrc, | 
|  | sequence_number, capture_time_ms, 250, false); | 
|  | clock_.AdvanceTimeMilliseconds(1); | 
|  | send_bucket_->InsertPacket(PacedSender::kNormalPriority, ssrc, | 
|  | sequence_number + 1, capture_time_ms + 1, 250, | 
|  | false); | 
|  | clock_.AdvanceTimeMilliseconds(9999); | 
|  | EXPECT_EQ(clock_.TimeInMilliseconds() - capture_time_ms, | 
|  | send_bucket_->QueueInMs()); | 
|  | // Fails to send first packet so only one call. | 
|  | EXPECT_CALL(callback_, TimeToSendPacket(ssrc, sequence_number, | 
|  | capture_time_ms, false, _)) | 
|  | .Times(1) | 
|  | .WillOnce(Return(false)); | 
|  | clock_.AdvanceTimeMilliseconds(10000); | 
|  | send_bucket_->Process(); | 
|  |  | 
|  | // Queue remains unchanged. | 
|  | EXPECT_EQ(clock_.TimeInMilliseconds() - capture_time_ms, | 
|  | send_bucket_->QueueInMs()); | 
|  |  | 
|  | // Fails to send second packet. | 
|  | EXPECT_CALL(callback_, TimeToSendPacket(ssrc, sequence_number, | 
|  | capture_time_ms, false, _)) | 
|  | .Times(1) | 
|  | .WillOnce(Return(true)); | 
|  | EXPECT_CALL(callback_, TimeToSendPacket(ssrc, sequence_number + 1, | 
|  | capture_time_ms + 1, false, _)) | 
|  | .Times(1) | 
|  | .WillOnce(Return(false)); | 
|  | clock_.AdvanceTimeMilliseconds(10000); | 
|  | send_bucket_->Process(); | 
|  |  | 
|  | // Queue is reduced by 1 packet. | 
|  | EXPECT_EQ(clock_.TimeInMilliseconds() - capture_time_ms - 1, | 
|  | send_bucket_->QueueInMs()); | 
|  |  | 
|  | // Send second packet and queue becomes empty. | 
|  | EXPECT_CALL(callback_, TimeToSendPacket(ssrc, sequence_number + 1, | 
|  | capture_time_ms + 1, false, _)) | 
|  | .Times(1) | 
|  | .WillOnce(Return(true)); | 
|  | clock_.AdvanceTimeMilliseconds(10000); | 
|  | send_bucket_->Process(); | 
|  | EXPECT_EQ(0, send_bucket_->QueueInMs()); | 
|  | } | 
|  |  | 
|  | TEST_F(PacedSenderTest, ExpectedQueueTimeMs) { | 
|  | uint32_t ssrc = 12346; | 
|  | uint16_t sequence_number = 1234; | 
|  | const size_t kNumPackets = 60; | 
|  | const size_t kPacketSize = 1200; | 
|  | const int32_t kMaxBitrate = PacedSender::kDefaultPaceMultiplier * 30000; | 
|  | EXPECT_EQ(0, send_bucket_->ExpectedQueueTimeMs()); | 
|  |  | 
|  | send_bucket_->SetEstimatedBitrate(30000); | 
|  | for (size_t i = 0; i < kNumPackets; ++i) { | 
|  | SendAndExpectPacket(PacedSender::kNormalPriority, ssrc, sequence_number++, | 
|  | clock_.TimeInMilliseconds(), kPacketSize, false); | 
|  | } | 
|  |  | 
|  | // Queue in ms = 1000 * (bytes in queue) *8 / (bits per second) | 
|  | int64_t queue_in_ms = | 
|  | static_cast<int64_t>(1000 * kNumPackets * kPacketSize * 8 / kMaxBitrate); | 
|  | EXPECT_EQ(queue_in_ms, send_bucket_->ExpectedQueueTimeMs()); | 
|  |  | 
|  | int64_t time_start = clock_.TimeInMilliseconds(); | 
|  | while (send_bucket_->QueueSizePackets() > 0) { | 
|  | int time_until_process = send_bucket_->TimeUntilNextProcess(); | 
|  | if (time_until_process <= 0) { | 
|  | send_bucket_->Process(); | 
|  | } else { | 
|  | clock_.AdvanceTimeMilliseconds(time_until_process); | 
|  | } | 
|  | } | 
|  | int64_t duration = clock_.TimeInMilliseconds() - time_start; | 
|  |  | 
|  | EXPECT_EQ(0, send_bucket_->ExpectedQueueTimeMs()); | 
|  |  | 
|  | // Allow for aliasing, duration should be within one pack of max time limit. | 
|  | EXPECT_NEAR(duration, PacedSender::kMaxQueueLengthMs, | 
|  | static_cast<int64_t>(1000 * kPacketSize * 8 / kMaxBitrate)); | 
|  | } | 
|  |  | 
|  | TEST_F(PacedSenderTest, QueueTimeGrowsOverTime) { | 
|  | uint32_t ssrc = 12346; | 
|  | uint16_t sequence_number = 1234; | 
|  | EXPECT_EQ(0, send_bucket_->QueueInMs()); | 
|  |  | 
|  | send_bucket_->SetEstimatedBitrate(30000); | 
|  | SendAndExpectPacket(PacedSender::kNormalPriority, | 
|  | ssrc, | 
|  | sequence_number, | 
|  | clock_.TimeInMilliseconds(), | 
|  | 1200, | 
|  | false); | 
|  |  | 
|  | clock_.AdvanceTimeMilliseconds(500); | 
|  | EXPECT_EQ(500, send_bucket_->QueueInMs()); | 
|  | send_bucket_->Process(); | 
|  | EXPECT_EQ(0, send_bucket_->QueueInMs()); | 
|  | } | 
|  |  | 
|  | TEST_F(PacedSenderTest, ProbingWithInsertedPackets) { | 
|  | const size_t kPacketSize = 1200; | 
|  | const int kInitialBitrateBps = 300000; | 
|  | uint32_t ssrc = 12346; | 
|  | uint16_t sequence_number = 1234; | 
|  |  | 
|  | PacedSenderProbing packet_sender; | 
|  | send_bucket_.reset(new PacedSender(&clock_, &packet_sender, nullptr)); | 
|  | send_bucket_->CreateProbeCluster(kFirstClusterBps); | 
|  | send_bucket_->CreateProbeCluster(kSecondClusterBps); | 
|  | send_bucket_->SetEstimatedBitrate(kInitialBitrateBps); | 
|  |  | 
|  | for (int i = 0; i < 10; ++i) { | 
|  | send_bucket_->InsertPacket(PacedSender::kNormalPriority, ssrc, | 
|  | sequence_number++, clock_.TimeInMilliseconds(), | 
|  | kPacketSize, false); | 
|  | } | 
|  |  | 
|  | int64_t start = clock_.TimeInMilliseconds(); | 
|  | while (packet_sender.packets_sent() < 5) { | 
|  | int time_until_process = send_bucket_->TimeUntilNextProcess(); | 
|  | clock_.AdvanceTimeMilliseconds(time_until_process); | 
|  | send_bucket_->Process(); | 
|  | } | 
|  | int packets_sent = packet_sender.packets_sent(); | 
|  | // Validate first cluster bitrate. Note that we have to account for number | 
|  | // of intervals and hence (packets_sent - 1) on the first cluster. | 
|  | EXPECT_NEAR((packets_sent - 1) * kPacketSize * 8000 / | 
|  | (clock_.TimeInMilliseconds() - start), | 
|  | kFirstClusterBps, kBitrateProbingError); | 
|  | EXPECT_EQ(0, packet_sender.padding_sent()); | 
|  |  | 
|  | clock_.AdvanceTimeMilliseconds(send_bucket_->TimeUntilNextProcess()); | 
|  | start = clock_.TimeInMilliseconds(); | 
|  | while (packet_sender.packets_sent() < 10) { | 
|  | int time_until_process = send_bucket_->TimeUntilNextProcess(); | 
|  | clock_.AdvanceTimeMilliseconds(time_until_process); | 
|  | send_bucket_->Process(); | 
|  | } | 
|  | packets_sent = packet_sender.packets_sent() - packets_sent; | 
|  | // Validate second cluster bitrate. | 
|  | EXPECT_NEAR((packets_sent - 1) * kPacketSize * 8000 / | 
|  | (clock_.TimeInMilliseconds() - start), | 
|  | kSecondClusterBps, kBitrateProbingError); | 
|  | } | 
|  |  | 
|  | TEST_F(PacedSenderTest, ProbingWithPaddingSupport) { | 
|  | const size_t kPacketSize = 1200; | 
|  | const int kInitialBitrateBps = 300000; | 
|  | uint32_t ssrc = 12346; | 
|  | uint16_t sequence_number = 1234; | 
|  |  | 
|  | PacedSenderProbing packet_sender; | 
|  | send_bucket_.reset(new PacedSender(&clock_, &packet_sender, nullptr)); | 
|  | send_bucket_->CreateProbeCluster(kFirstClusterBps); | 
|  | send_bucket_->SetEstimatedBitrate(kInitialBitrateBps); | 
|  |  | 
|  | for (int i = 0; i < 3; ++i) { | 
|  | send_bucket_->InsertPacket(PacedSender::kNormalPriority, ssrc, | 
|  | sequence_number++, clock_.TimeInMilliseconds(), | 
|  | kPacketSize, false); | 
|  | } | 
|  |  | 
|  | int64_t start = clock_.TimeInMilliseconds(); | 
|  | int process_count = 0; | 
|  | while (process_count < 5) { | 
|  | int time_until_process = send_bucket_->TimeUntilNextProcess(); | 
|  | clock_.AdvanceTimeMilliseconds(time_until_process); | 
|  | send_bucket_->Process(); | 
|  | ++process_count; | 
|  | } | 
|  | int packets_sent = packet_sender.packets_sent(); | 
|  | int padding_sent = packet_sender.padding_sent(); | 
|  | EXPECT_GT(packets_sent, 0); | 
|  | EXPECT_GT(padding_sent, 0); | 
|  | // Note that the number of intervals here for kPacketSize is | 
|  | // packets_sent due to padding in the same cluster. | 
|  | EXPECT_NEAR((packets_sent * kPacketSize * 8000 + padding_sent) / | 
|  | (clock_.TimeInMilliseconds() - start), | 
|  | kFirstClusterBps, kBitrateProbingError); | 
|  | } | 
|  |  | 
|  | TEST_F(PacedSenderTest, PriorityInversion) { | 
|  | uint32_t ssrc = 12346; | 
|  | uint16_t sequence_number = 1234; | 
|  | const size_t kPacketSize = 1200; | 
|  |  | 
|  | send_bucket_->InsertPacket( | 
|  | PacedSender::kHighPriority, ssrc, sequence_number + 3, | 
|  | clock_.TimeInMilliseconds() + 33, kPacketSize, true); | 
|  |  | 
|  | send_bucket_->InsertPacket( | 
|  | PacedSender::kHighPriority, ssrc, sequence_number + 2, | 
|  | clock_.TimeInMilliseconds() + 33, kPacketSize, true); | 
|  |  | 
|  | send_bucket_->InsertPacket(PacedSender::kHighPriority, ssrc, sequence_number, | 
|  | clock_.TimeInMilliseconds(), kPacketSize, true); | 
|  |  | 
|  | send_bucket_->InsertPacket(PacedSender::kHighPriority, ssrc, | 
|  | sequence_number + 1, clock_.TimeInMilliseconds(), | 
|  | kPacketSize, true); | 
|  |  | 
|  | // Packets from earlier frames should be sent first. | 
|  | { | 
|  | ::testing::InSequence sequence; | 
|  | EXPECT_CALL(callback_, | 
|  | TimeToSendPacket(ssrc, sequence_number, | 
|  | clock_.TimeInMilliseconds(), true, _)) | 
|  | .WillOnce(Return(true)); | 
|  | EXPECT_CALL(callback_, | 
|  | TimeToSendPacket(ssrc, sequence_number + 1, | 
|  | clock_.TimeInMilliseconds(), true, _)) | 
|  | .WillOnce(Return(true)); | 
|  | EXPECT_CALL(callback_, | 
|  | TimeToSendPacket(ssrc, sequence_number + 3, | 
|  | clock_.TimeInMilliseconds() + 33, true, _)) | 
|  | .WillOnce(Return(true)); | 
|  | EXPECT_CALL(callback_, | 
|  | TimeToSendPacket(ssrc, sequence_number + 2, | 
|  | clock_.TimeInMilliseconds() + 33, true, _)) | 
|  | .WillOnce(Return(true)); | 
|  |  | 
|  | while (send_bucket_->QueueSizePackets() > 0) { | 
|  | int time_until_process = send_bucket_->TimeUntilNextProcess(); | 
|  | if (time_until_process <= 0) { | 
|  | send_bucket_->Process(); | 
|  | } else { | 
|  | clock_.AdvanceTimeMilliseconds(time_until_process); | 
|  | } | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  | TEST_F(PacedSenderTest, PaddingOveruse) { | 
|  | uint32_t ssrc = 12346; | 
|  | uint16_t sequence_number = 1234; | 
|  | const size_t kPacketSize = 1200; | 
|  |  | 
|  | send_bucket_->Process(); | 
|  | send_bucket_->SetEstimatedBitrate(60000); | 
|  | send_bucket_->SetSendBitrateLimits(60000, 0); | 
|  |  | 
|  | SendAndExpectPacket(PacedSender::kNormalPriority, ssrc, sequence_number++, | 
|  | clock_.TimeInMilliseconds(), kPacketSize, false); | 
|  | send_bucket_->Process(); | 
|  |  | 
|  | // Add 30kbit padding. When increasing budget, media budget will increase from | 
|  | // negative (overuse) while padding budget will increase from 0. | 
|  | clock_.AdvanceTimeMilliseconds(5); | 
|  | send_bucket_->SetSendBitrateLimits(60000, 30000); | 
|  |  | 
|  | SendAndExpectPacket(PacedSender::kNormalPriority, ssrc, sequence_number++, | 
|  | clock_.TimeInMilliseconds(), kPacketSize, false); | 
|  | EXPECT_LT(5u, send_bucket_->ExpectedQueueTimeMs()); | 
|  | // Don't send padding if queue is non-empty, even if padding budget > 0. | 
|  | EXPECT_CALL(callback_, TimeToSendPadding(_, _)).Times(0); | 
|  | send_bucket_->Process(); | 
|  | } | 
|  |  | 
|  | TEST_F(PacedSenderTest, AverageQueueTime) { | 
|  | uint32_t ssrc = 12346; | 
|  | uint16_t sequence_number = 1234; | 
|  | const size_t kPacketSize = 1200; | 
|  | const int kBitrateBps = 10 * kPacketSize * 8;  // 10 packets per second. | 
|  |  | 
|  | send_bucket_->SetEstimatedBitrate(kBitrateBps); | 
|  |  | 
|  | EXPECT_EQ(0, send_bucket_->AverageQueueTimeMs()); | 
|  |  | 
|  | int64_t first_capture_time = clock_.TimeInMilliseconds(); | 
|  | send_bucket_->InsertPacket(PacedSender::kNormalPriority, ssrc, | 
|  | sequence_number, first_capture_time, kPacketSize, | 
|  | false); | 
|  | clock_.AdvanceTimeMilliseconds(10); | 
|  | send_bucket_->InsertPacket(PacedSender::kNormalPriority, ssrc, | 
|  | sequence_number + 1, clock_.TimeInMilliseconds(), | 
|  | kPacketSize, false); | 
|  | clock_.AdvanceTimeMilliseconds(10); | 
|  |  | 
|  | EXPECT_EQ((20 + 10) / 2, send_bucket_->AverageQueueTimeMs()); | 
|  |  | 
|  | // Only first packet (queued for 20ms) should be removed, leave the second | 
|  | // packet (queued for 10ms) alone in the queue. | 
|  | EXPECT_CALL(callback_, TimeToSendPacket(ssrc, sequence_number, | 
|  | first_capture_time, false, _)) | 
|  | .Times(1) | 
|  | .WillRepeatedly(Return(true)); | 
|  | send_bucket_->Process(); | 
|  |  | 
|  | EXPECT_EQ(10, send_bucket_->AverageQueueTimeMs()); | 
|  |  | 
|  | clock_.AdvanceTimeMilliseconds(10); | 
|  | EXPECT_CALL(callback_, TimeToSendPacket(ssrc, sequence_number + 1, | 
|  | first_capture_time + 10, false, _)) | 
|  | .Times(1) | 
|  | .WillRepeatedly(Return(true)); | 
|  | for (int i = 0; i < 3; ++i) { | 
|  | clock_.AdvanceTimeMilliseconds(30);  // Max delta. | 
|  | send_bucket_->Process(); | 
|  | } | 
|  |  | 
|  | EXPECT_EQ(0, send_bucket_->AverageQueueTimeMs()); | 
|  | } | 
|  |  | 
|  | TEST_F(PacedSenderTest, ProbeClusterId) { | 
|  | uint32_t ssrc = 12346; | 
|  | uint16_t sequence_number = 1234; | 
|  | const size_t kPacketSize = 1200; | 
|  |  | 
|  | send_bucket_->SetSendBitrateLimits(kTargetBitrateBps, kTargetBitrateBps); | 
|  | send_bucket_->SetProbingEnabled(true); | 
|  | for (int i = 0; i < 10; ++i) { | 
|  | send_bucket_->InsertPacket(PacedSender::kNormalPriority, ssrc, | 
|  | sequence_number + i, clock_.TimeInMilliseconds(), | 
|  | kPacketSize, false); | 
|  | } | 
|  |  | 
|  | // First probing cluster. | 
|  | EXPECT_CALL(callback_, | 
|  | TimeToSendPacket(_, _, _, _, | 
|  | Field(&PacedPacketInfo::probe_cluster_id, 0))) | 
|  | .Times(5) | 
|  | .WillRepeatedly(Return(true)); | 
|  | for (int i = 0; i < 5; ++i) { | 
|  | clock_.AdvanceTimeMilliseconds(20); | 
|  | send_bucket_->Process(); | 
|  | } | 
|  |  | 
|  | // Second probing cluster. | 
|  | EXPECT_CALL(callback_, | 
|  | TimeToSendPacket(_, _, _, _, | 
|  | Field(&PacedPacketInfo::probe_cluster_id, 1))) | 
|  | .Times(5) | 
|  | .WillRepeatedly(Return(true)); | 
|  | for (int i = 0; i < 5; ++i) { | 
|  | clock_.AdvanceTimeMilliseconds(20); | 
|  | send_bucket_->Process(); | 
|  | } | 
|  |  | 
|  | // Needed for the Field comparer below. | 
|  | const int kNotAProbe = PacedPacketInfo::kNotAProbe; | 
|  | // No more probing packets. | 
|  | EXPECT_CALL(callback_, | 
|  | TimeToSendPadding( | 
|  | _, Field(&PacedPacketInfo::probe_cluster_id, kNotAProbe))) | 
|  | .Times(1) | 
|  | .WillRepeatedly(Return(500)); | 
|  | send_bucket_->Process(); | 
|  | } | 
|  |  | 
|  | TEST_F(PacedSenderTest, AvoidBusyLoopOnSendFailure) { | 
|  | uint32_t ssrc = 12346; | 
|  | uint16_t sequence_number = 1234; | 
|  | const size_t kPacketSize = kFirstClusterBps / (8000 / 10); | 
|  |  | 
|  | send_bucket_->SetSendBitrateLimits(kTargetBitrateBps, kTargetBitrateBps); | 
|  | send_bucket_->SetProbingEnabled(true); | 
|  | send_bucket_->InsertPacket(PacedSender::kNormalPriority, ssrc, | 
|  | sequence_number, clock_.TimeInMilliseconds(), | 
|  | kPacketSize, false); | 
|  |  | 
|  | EXPECT_CALL(callback_, TimeToSendPacket(_, _, _, _, _)) | 
|  | .WillOnce(Return(true)); | 
|  | send_bucket_->Process(); | 
|  | EXPECT_EQ(10, send_bucket_->TimeUntilNextProcess()); | 
|  | clock_.AdvanceTimeMilliseconds(9); | 
|  |  | 
|  | EXPECT_CALL(callback_, TimeToSendPadding(_, _)) | 
|  | .Times(2) | 
|  | .WillRepeatedly(Return(0)); | 
|  | send_bucket_->Process(); | 
|  | EXPECT_EQ(1, send_bucket_->TimeUntilNextProcess()); | 
|  | clock_.AdvanceTimeMilliseconds(1); | 
|  | send_bucket_->Process(); | 
|  | EXPECT_EQ(5, send_bucket_->TimeUntilNextProcess()); | 
|  | } | 
|  |  | 
|  | }  // namespace test | 
|  | }  // namespace webrtc |