| /* |
| * Copyright (c) 2015 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 "modules/congestion_controller/rtp/transport_feedback_adapter.h" |
| |
| #include <stdlib.h> |
| #include <algorithm> |
| #include <cmath> |
| |
| #include "api/units/timestamp.h" |
| #include "modules/rtp_rtcp/include/rtp_rtcp_defines.h" |
| #include "modules/rtp_rtcp/source/rtcp_packet/transport_feedback.h" |
| #include "rtc_base/checks.h" |
| #include "rtc_base/logging.h" |
| #include "system_wrappers/include/field_trial.h" |
| |
| namespace webrtc { |
| namespace { |
| |
| PacketResult NetworkPacketFeedbackFromRtpPacketFeedback( |
| const webrtc::PacketFeedback& pf) { |
| PacketResult feedback; |
| if (pf.arrival_time_ms == webrtc::PacketFeedback::kNotReceived) { |
| feedback.receive_time = Timestamp::PlusInfinity(); |
| } else { |
| feedback.receive_time = Timestamp::ms(pf.arrival_time_ms); |
| } |
| feedback.sent_packet.sequence_number = pf.long_sequence_number; |
| feedback.sent_packet.send_time = Timestamp::ms(pf.send_time_ms); |
| feedback.sent_packet.size = DataSize::bytes(pf.payload_size); |
| feedback.sent_packet.pacing_info = pf.pacing_info; |
| feedback.sent_packet.prior_unacked_data = |
| DataSize::bytes(pf.unacknowledged_data); |
| return feedback; |
| } |
| } // namespace |
| const int64_t kNoTimestamp = -1; |
| const int64_t kSendTimeHistoryWindowMs = 60000; |
| const int64_t kBaseTimestampScaleFactor = |
| rtcp::TransportFeedback::kDeltaScaleFactor * (1 << 8); |
| const int64_t kBaseTimestampRangeSizeUs = kBaseTimestampScaleFactor * (1 << 24); |
| |
| TransportFeedbackAdapter::TransportFeedbackAdapter() |
| : allow_duplicates_(field_trial::IsEnabled( |
| "WebRTC-TransportFeedbackAdapter-AllowDuplicates")), |
| send_time_history_(kSendTimeHistoryWindowMs), |
| current_offset_ms_(kNoTimestamp), |
| last_timestamp_us_(kNoTimestamp), |
| local_net_id_(0), |
| remote_net_id_(0) {} |
| |
| TransportFeedbackAdapter::~TransportFeedbackAdapter() { |
| RTC_DCHECK(observers_.empty()); |
| } |
| |
| void TransportFeedbackAdapter::RegisterPacketFeedbackObserver( |
| PacketFeedbackObserver* observer) { |
| rtc::CritScope cs(&observers_lock_); |
| RTC_DCHECK(observer); |
| RTC_DCHECK(std::find(observers_.begin(), observers_.end(), observer) == |
| observers_.end()); |
| observers_.push_back(observer); |
| } |
| |
| void TransportFeedbackAdapter::DeRegisterPacketFeedbackObserver( |
| PacketFeedbackObserver* observer) { |
| rtc::CritScope cs(&observers_lock_); |
| RTC_DCHECK(observer); |
| const auto it = std::find(observers_.begin(), observers_.end(), observer); |
| RTC_DCHECK(it != observers_.end()); |
| observers_.erase(it); |
| } |
| |
| void TransportFeedbackAdapter::AddPacket(uint32_t ssrc, |
| uint16_t sequence_number, |
| size_t length, |
| const PacedPacketInfo& pacing_info, |
| Timestamp creation_time) { |
| RtpPacketSendInfo packet_info; |
| packet_info.ssrc = ssrc; |
| packet_info.transport_sequence_number = sequence_number; |
| packet_info.length = length; |
| packet_info.pacing_info = pacing_info; |
| AddPacket(packet_info, 0u, creation_time); |
| } |
| |
| void TransportFeedbackAdapter::AddPacket(const RtpPacketSendInfo& packet_info, |
| size_t overhead_bytes, |
| Timestamp creation_time) { |
| { |
| rtc::CritScope cs(&lock_); |
| PacketFeedback packet_feedback( |
| creation_time.ms(), packet_info.transport_sequence_number, |
| packet_info.length + overhead_bytes, local_net_id_, remote_net_id_, |
| packet_info.pacing_info); |
| if (packet_info.has_rtp_sequence_number) { |
| packet_feedback.ssrc = packet_info.ssrc; |
| packet_feedback.rtp_sequence_number = packet_info.rtp_sequence_number; |
| } |
| send_time_history_.AddAndRemoveOld(packet_feedback, creation_time.ms()); |
| } |
| |
| { |
| rtc::CritScope cs(&observers_lock_); |
| for (auto* observer : observers_) { |
| observer->OnPacketAdded(packet_info.ssrc, |
| packet_info.transport_sequence_number); |
| } |
| } |
| } |
| absl::optional<SentPacket> TransportFeedbackAdapter::ProcessSentPacket( |
| const rtc::SentPacket& sent_packet) { |
| rtc::CritScope cs(&lock_); |
| // TODO(srte): Only use one way to indicate that packet feedback is used. |
| if (sent_packet.info.included_in_feedback || sent_packet.packet_id != -1) { |
| SendTimeHistory::Status send_status = send_time_history_.OnSentPacket( |
| sent_packet.packet_id, sent_packet.send_time_ms); |
| absl::optional<PacketFeedback> packet; |
| if (allow_duplicates_ || |
| send_status != SendTimeHistory::Status::kDuplicate) { |
| packet = send_time_history_.GetPacket(sent_packet.packet_id); |
| } |
| |
| if (packet) { |
| SentPacket msg; |
| msg.size = DataSize::bytes(packet->payload_size); |
| msg.send_time = Timestamp::ms(packet->send_time_ms); |
| msg.sequence_number = packet->long_sequence_number; |
| msg.prior_unacked_data = DataSize::bytes(packet->unacknowledged_data); |
| msg.data_in_flight = |
| send_time_history_.GetOutstandingData(local_net_id_, remote_net_id_); |
| return msg; |
| } |
| } else if (sent_packet.info.included_in_allocation) { |
| send_time_history_.AddUntracked(sent_packet.info.packet_size_bytes, |
| sent_packet.send_time_ms); |
| } |
| return absl::nullopt; |
| } |
| |
| absl::optional<TransportPacketsFeedback> |
| TransportFeedbackAdapter::ProcessTransportFeedback( |
| const rtcp::TransportFeedback& feedback, |
| Timestamp feedback_receive_time) { |
| DataSize prior_in_flight = GetOutstandingData(); |
| |
| last_packet_feedback_vector_ = |
| GetPacketFeedbackVector(feedback, feedback_receive_time); |
| { |
| rtc::CritScope cs(&observers_lock_); |
| for (auto* observer : observers_) { |
| observer->OnPacketFeedbackVector(last_packet_feedback_vector_); |
| } |
| } |
| |
| std::vector<PacketFeedback> feedback_vector = last_packet_feedback_vector_; |
| if (feedback_vector.empty()) |
| return absl::nullopt; |
| |
| TransportPacketsFeedback msg; |
| for (const PacketFeedback& rtp_feedback : feedback_vector) { |
| if (rtp_feedback.send_time_ms != PacketFeedback::kNoSendTime) { |
| auto feedback = NetworkPacketFeedbackFromRtpPacketFeedback(rtp_feedback); |
| msg.packet_feedbacks.push_back(feedback); |
| } else if (rtp_feedback.arrival_time_ms == PacketFeedback::kNotReceived) { |
| msg.sendless_arrival_times.push_back(Timestamp::PlusInfinity()); |
| } else { |
| msg.sendless_arrival_times.push_back( |
| Timestamp::ms(rtp_feedback.arrival_time_ms)); |
| } |
| } |
| { |
| rtc::CritScope cs(&lock_); |
| absl::optional<int64_t> first_unacked_send_time_ms = |
| send_time_history_.GetFirstUnackedSendTime(); |
| if (first_unacked_send_time_ms) |
| msg.first_unacked_send_time = Timestamp::ms(*first_unacked_send_time_ms); |
| } |
| msg.feedback_time = feedback_receive_time; |
| msg.prior_in_flight = prior_in_flight; |
| msg.data_in_flight = GetOutstandingData(); |
| return msg; |
| } |
| |
| void TransportFeedbackAdapter::SetNetworkIds(uint16_t local_id, |
| uint16_t remote_id) { |
| rtc::CritScope cs(&lock_); |
| local_net_id_ = local_id; |
| remote_net_id_ = remote_id; |
| } |
| |
| DataSize TransportFeedbackAdapter::GetOutstandingData() const { |
| rtc::CritScope cs(&lock_); |
| return send_time_history_.GetOutstandingData(local_net_id_, remote_net_id_); |
| } |
| |
| std::vector<PacketFeedback> TransportFeedbackAdapter::GetPacketFeedbackVector( |
| const rtcp::TransportFeedback& feedback, |
| Timestamp feedback_time) { |
| int64_t timestamp_us = feedback.GetBaseTimeUs(); |
| |
| // Add timestamp deltas to a local time base selected on first packet arrival. |
| // This won't be the true time base, but makes it easier to manually inspect |
| // time stamps. |
| if (last_timestamp_us_ == kNoTimestamp) { |
| current_offset_ms_ = feedback_time.ms(); |
| } else { |
| int64_t delta = timestamp_us - last_timestamp_us_; |
| |
| // Detect and compensate for wrap-arounds in base time. |
| if (std::abs(delta - kBaseTimestampRangeSizeUs) < std::abs(delta)) { |
| delta -= kBaseTimestampRangeSizeUs; // Wrap backwards. |
| } else if (std::abs(delta + kBaseTimestampRangeSizeUs) < std::abs(delta)) { |
| delta += kBaseTimestampRangeSizeUs; // Wrap forwards. |
| } |
| |
| current_offset_ms_ += delta / 1000; |
| } |
| last_timestamp_us_ = timestamp_us; |
| |
| std::vector<PacketFeedback> packet_feedback_vector; |
| if (feedback.GetPacketStatusCount() == 0) { |
| RTC_LOG(LS_INFO) << "Empty transport feedback packet received."; |
| return packet_feedback_vector; |
| } |
| packet_feedback_vector.reserve(feedback.GetPacketStatusCount()); |
| { |
| rtc::CritScope cs(&lock_); |
| size_t failed_lookups = 0; |
| int64_t offset_us = 0; |
| int64_t timestamp_ms = 0; |
| uint16_t seq_num = feedback.GetBaseSequence(); |
| for (const auto& packet : feedback.GetReceivedPackets()) { |
| // Insert into the vector those unreceived packets which precede this |
| // iteration's received packet. |
| for (; seq_num != packet.sequence_number(); ++seq_num) { |
| PacketFeedback packet_feedback(PacketFeedback::kNotReceived, seq_num); |
| // Note: Element not removed from history because it might be reported |
| // as received by another feedback. |
| if (!send_time_history_.GetFeedback(&packet_feedback, false)) |
| ++failed_lookups; |
| if (packet_feedback.local_net_id == local_net_id_ && |
| packet_feedback.remote_net_id == remote_net_id_) { |
| packet_feedback_vector.push_back(packet_feedback); |
| } |
| } |
| |
| // Handle this iteration's received packet. |
| offset_us += packet.delta_us(); |
| timestamp_ms = current_offset_ms_ + (offset_us / 1000); |
| PacketFeedback packet_feedback(timestamp_ms, packet.sequence_number()); |
| if (!send_time_history_.GetFeedback(&packet_feedback, true)) |
| ++failed_lookups; |
| if (packet_feedback.local_net_id == local_net_id_ && |
| packet_feedback.remote_net_id == remote_net_id_) { |
| packet_feedback_vector.push_back(packet_feedback); |
| } |
| |
| ++seq_num; |
| } |
| |
| if (failed_lookups > 0) { |
| RTC_LOG(LS_WARNING) << "Failed to lookup send time for " << failed_lookups |
| << " packet" << (failed_lookups > 1 ? "s" : "") |
| << ". Send time history too small?"; |
| } |
| } |
| return packet_feedback_vector; |
| } |
| |
| std::vector<PacketFeedback> |
| TransportFeedbackAdapter::GetTransportFeedbackVector() const { |
| return last_packet_feedback_vector_; |
| } |
| |
| } // namespace webrtc |
