| /* |
| * 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 "modules/rtp_rtcp/source/rtp_sender.h" |
| |
| #include <algorithm> |
| #include <limits> |
| #include <string> |
| #include <utility> |
| |
| #include "absl/memory/memory.h" |
| #include "absl/strings/match.h" |
| #include "api/array_view.h" |
| #include "logging/rtc_event_log/events/rtc_event_rtp_packet_outgoing.h" |
| #include "logging/rtc_event_log/rtc_event_log.h" |
| #include "modules/rtp_rtcp/include/rtp_cvo.h" |
| #include "modules/rtp_rtcp/source/byte_io.h" |
| #include "modules/rtp_rtcp/source/rtp_generic_frame_descriptor_extension.h" |
| #include "modules/rtp_rtcp/source/rtp_header_extensions.h" |
| #include "modules/rtp_rtcp/source/rtp_packet_to_send.h" |
| #include "modules/rtp_rtcp/source/time_util.h" |
| #include "rtc_base/arraysize.h" |
| #include "rtc_base/checks.h" |
| #include "rtc_base/logging.h" |
| #include "rtc_base/numerics/safe_minmax.h" |
| #include "rtc_base/rate_limiter.h" |
| #include "rtc_base/time_utils.h" |
| |
| namespace webrtc { |
| |
| namespace { |
| // Max in the RFC 3550 is 255 bytes, we limit it to be modulus 32 for SRTP. |
| constexpr size_t kMaxPaddingLength = 224; |
| constexpr size_t kMinAudioPaddingLength = 50; |
| constexpr int kSendSideDelayWindowMs = 1000; |
| constexpr size_t kRtpHeaderLength = 12; |
| constexpr uint16_t kMaxInitRtpSeqNumber = 32767; // 2^15 -1. |
| constexpr uint32_t kTimestampTicksPerMs = 90; |
| constexpr int kBitrateStatisticsWindowMs = 1000; |
| |
| constexpr size_t kMinFlexfecPacketsToStoreForPacing = 50; |
| |
| // Min size needed to get payload padding from packet history. |
| constexpr int kMinPayloadPaddingBytes = 50; |
| |
| template <typename Extension> |
| constexpr RtpExtensionSize CreateExtensionSize() { |
| return {Extension::kId, Extension::kValueSizeBytes}; |
| } |
| |
| template <typename Extension> |
| constexpr RtpExtensionSize CreateMaxExtensionSize() { |
| return {Extension::kId, Extension::kMaxValueSizeBytes}; |
| } |
| |
| // Size info for header extensions that might be used in padding or FEC packets. |
| constexpr RtpExtensionSize kFecOrPaddingExtensionSizes[] = { |
| CreateExtensionSize<AbsoluteSendTime>(), |
| CreateExtensionSize<TransmissionOffset>(), |
| CreateExtensionSize<TransportSequenceNumber>(), |
| CreateExtensionSize<PlayoutDelayLimits>(), |
| CreateMaxExtensionSize<RtpMid>(), |
| }; |
| |
| // Size info for header extensions that might be used in video packets. |
| constexpr RtpExtensionSize kVideoExtensionSizes[] = { |
| CreateExtensionSize<AbsoluteSendTime>(), |
| CreateExtensionSize<TransmissionOffset>(), |
| CreateExtensionSize<TransportSequenceNumber>(), |
| CreateExtensionSize<PlayoutDelayLimits>(), |
| CreateExtensionSize<VideoOrientation>(), |
| CreateExtensionSize<VideoContentTypeExtension>(), |
| CreateExtensionSize<VideoTimingExtension>(), |
| CreateMaxExtensionSize<RtpStreamId>(), |
| CreateMaxExtensionSize<RepairedRtpStreamId>(), |
| CreateMaxExtensionSize<RtpMid>(), |
| {RtpGenericFrameDescriptorExtension00::kId, |
| RtpGenericFrameDescriptorExtension00::kMaxSizeBytes}, |
| {RtpGenericFrameDescriptorExtension01::kId, |
| RtpGenericFrameDescriptorExtension01::kMaxSizeBytes}, |
| }; |
| |
| // TODO(bugs.webrtc.org/10633): Remove when downstream code stops using |
| // priority. At the time of writing, the priority can be directly mapped to a |
| // packet type. This is only for a transition period. |
| RtpPacketToSend::Type PacketPriorityToType(RtpPacketSender::Priority priority) { |
| switch (priority) { |
| case RtpPacketSender::Priority::kLowPriority: |
| return RtpPacketToSend::Type::kVideo; |
| case RtpPacketSender::Priority::kNormalPriority: |
| return RtpPacketToSend::Type::kRetransmission; |
| case RtpPacketSender::Priority::kHighPriority: |
| return RtpPacketToSend::Type::kAudio; |
| default: |
| RTC_NOTREACHED() << "Unexpected priority: " << priority; |
| return RtpPacketToSend::Type::kVideo; |
| } |
| } |
| |
| // TODO(bugs.webrtc.org/10633): Remove when packets are always owned by pacer. |
| RtpPacketSender::Priority PacketTypeToPriority(RtpPacketToSend::Type type) { |
| switch (type) { |
| case RtpPacketToSend::Type::kAudio: |
| return RtpPacketSender::Priority::kHighPriority; |
| case RtpPacketToSend::Type::kVideo: |
| return RtpPacketSender::Priority::kLowPriority; |
| case RtpPacketToSend::Type::kRetransmission: |
| return RtpPacketSender::Priority::kNormalPriority; |
| case RtpPacketToSend::Type::kForwardErrorCorrection: |
| return RtpPacketSender::Priority::kLowPriority; |
| break; |
| case RtpPacketToSend::Type::kPadding: |
| RTC_NOTREACHED() << "Unexpected type for legacy path: kPadding"; |
| break; |
| } |
| return RtpPacketSender::Priority::kLowPriority; |
| } |
| |
| } // namespace |
| |
| RTPSender::RTPSender( |
| bool audio, |
| Clock* clock, |
| Transport* transport, |
| RtpPacketPacer* paced_sender, |
| absl::optional<uint32_t> flexfec_ssrc, |
| TransportSequenceNumberAllocator* sequence_number_allocator, |
| TransportFeedbackObserver* transport_feedback_observer, |
| BitrateStatisticsObserver* bitrate_callback, |
| SendSideDelayObserver* send_side_delay_observer, |
| RtcEventLog* event_log, |
| SendPacketObserver* send_packet_observer, |
| RateLimiter* retransmission_rate_limiter, |
| OverheadObserver* overhead_observer, |
| bool populate_network2_timestamp, |
| FrameEncryptorInterface* frame_encryptor, |
| bool require_frame_encryption, |
| bool extmap_allow_mixed, |
| const WebRtcKeyValueConfig& field_trials) |
| : clock_(clock), |
| random_(clock_->TimeInMicroseconds()), |
| audio_configured_(audio), |
| flexfec_ssrc_(flexfec_ssrc), |
| paced_sender_(paced_sender), |
| transport_sequence_number_allocator_(sequence_number_allocator), |
| transport_feedback_observer_(transport_feedback_observer), |
| transport_(transport), |
| sending_media_(true), // Default to sending media. |
| force_part_of_allocation_(false), |
| max_packet_size_(IP_PACKET_SIZE - 28), // Default is IP-v4/UDP. |
| last_payload_type_(-1), |
| rtp_header_extension_map_(extmap_allow_mixed), |
| packet_history_(clock), |
| flexfec_packet_history_(clock), |
| // Statistics |
| send_delays_(), |
| max_delay_it_(send_delays_.end()), |
| sum_delays_ms_(0), |
| total_packet_send_delay_ms_(0), |
| rtp_stats_callback_(nullptr), |
| total_bitrate_sent_(kBitrateStatisticsWindowMs, |
| RateStatistics::kBpsScale), |
| nack_bitrate_sent_(kBitrateStatisticsWindowMs, RateStatistics::kBpsScale), |
| send_side_delay_observer_(send_side_delay_observer), |
| event_log_(event_log), |
| send_packet_observer_(send_packet_observer), |
| bitrate_callback_(bitrate_callback), |
| // RTP variables |
| sequence_number_forced_(false), |
| last_rtp_timestamp_(0), |
| capture_time_ms_(0), |
| last_timestamp_time_ms_(0), |
| media_has_been_sent_(false), |
| last_packet_marker_bit_(false), |
| csrcs_(), |
| rtx_(kRtxOff), |
| rtp_overhead_bytes_per_packet_(0), |
| retransmission_rate_limiter_(retransmission_rate_limiter), |
| overhead_observer_(overhead_observer), |
| populate_network2_timestamp_(populate_network2_timestamp), |
| send_side_bwe_with_overhead_( |
| field_trials.Lookup("WebRTC-SendSideBwe-WithOverhead") |
| .find("Enabled") == 0), |
| legacy_packet_history_storage_mode_( |
| field_trials.Lookup("WebRTC-UseRtpPacketHistoryLegacyStorageMode") |
| .find("Enabled") == 0), |
| payload_padding_prefer_useful_packets_( |
| field_trials.Lookup("WebRTC-PayloadPadding-UseMostUsefulPacket") |
| .find("Disabled") != 0) { |
| // This random initialization is not intended to be cryptographic strong. |
| timestamp_offset_ = random_.Rand<uint32_t>(); |
| // Random start, 16 bits. Can't be 0. |
| sequence_number_rtx_ = random_.Rand(1, kMaxInitRtpSeqNumber); |
| sequence_number_ = random_.Rand(1, kMaxInitRtpSeqNumber); |
| |
| // Store FlexFEC packets in the packet history data structure, so they can |
| // be found when paced. |
| if (flexfec_ssrc_) { |
| RtpPacketHistory::StorageMode storage_mode = |
| legacy_packet_history_storage_mode_ |
| ? RtpPacketHistory::StorageMode::kStore |
| : RtpPacketHistory::StorageMode::kStoreAndCull; |
| |
| flexfec_packet_history_.SetStorePacketsStatus( |
| storage_mode, kMinFlexfecPacketsToStoreForPacing); |
| } |
| } |
| |
| RTPSender::~RTPSender() { |
| // TODO(tommi): Use a thread checker to ensure the object is created and |
| // deleted on the same thread. At the moment this isn't possible due to |
| // voe::ChannelOwner in voice engine. To reproduce, run: |
| // voe_auto_test --automated --gtest_filter=*MixManyChannelsForStressOpus |
| |
| // TODO(tommi,holmer): We don't grab locks in the dtor before accessing member |
| // variables but we grab them in all other methods. (what's the design?) |
| // Start documenting what thread we're on in what method so that it's easier |
| // to understand performance attributes and possibly remove locks. |
| } |
| |
| rtc::ArrayView<const RtpExtensionSize> RTPSender::FecExtensionSizes() { |
| return rtc::MakeArrayView(kFecOrPaddingExtensionSizes, |
| arraysize(kFecOrPaddingExtensionSizes)); |
| } |
| |
| rtc::ArrayView<const RtpExtensionSize> RTPSender::VideoExtensionSizes() { |
| return rtc::MakeArrayView(kVideoExtensionSizes, |
| arraysize(kVideoExtensionSizes)); |
| } |
| |
| uint16_t RTPSender::ActualSendBitrateKbit() const { |
| rtc::CritScope cs(&statistics_crit_); |
| return static_cast<uint16_t>( |
| total_bitrate_sent_.Rate(clock_->TimeInMilliseconds()).value_or(0) / |
| 1000); |
| } |
| |
| uint32_t RTPSender::NackOverheadRate() const { |
| rtc::CritScope cs(&statistics_crit_); |
| return nack_bitrate_sent_.Rate(clock_->TimeInMilliseconds()).value_or(0); |
| } |
| |
| void RTPSender::SetExtmapAllowMixed(bool extmap_allow_mixed) { |
| rtc::CritScope lock(&send_critsect_); |
| rtp_header_extension_map_.SetExtmapAllowMixed(extmap_allow_mixed); |
| } |
| |
| int32_t RTPSender::RegisterRtpHeaderExtension(RTPExtensionType type, |
| uint8_t id) { |
| rtc::CritScope lock(&send_critsect_); |
| return rtp_header_extension_map_.RegisterByType(id, type) ? 0 : -1; |
| } |
| |
| bool RTPSender::RegisterRtpHeaderExtension(const std::string& uri, int id) { |
| rtc::CritScope lock(&send_critsect_); |
| return rtp_header_extension_map_.RegisterByUri(id, uri); |
| } |
| |
| bool RTPSender::IsRtpHeaderExtensionRegistered(RTPExtensionType type) const { |
| rtc::CritScope lock(&send_critsect_); |
| return rtp_header_extension_map_.IsRegistered(type); |
| } |
| |
| int32_t RTPSender::DeregisterRtpHeaderExtension(RTPExtensionType type) { |
| rtc::CritScope lock(&send_critsect_); |
| return rtp_header_extension_map_.Deregister(type); |
| } |
| |
| void RTPSender::SetMaxRtpPacketSize(size_t max_packet_size) { |
| RTC_DCHECK_GE(max_packet_size, 100); |
| RTC_DCHECK_LE(max_packet_size, IP_PACKET_SIZE); |
| rtc::CritScope lock(&send_critsect_); |
| max_packet_size_ = max_packet_size; |
| } |
| |
| size_t RTPSender::MaxRtpPacketSize() const { |
| return max_packet_size_; |
| } |
| |
| void RTPSender::SetRtxStatus(int mode) { |
| rtc::CritScope lock(&send_critsect_); |
| rtx_ = mode; |
| } |
| |
| int RTPSender::RtxStatus() const { |
| rtc::CritScope lock(&send_critsect_); |
| return rtx_; |
| } |
| |
| void RTPSender::SetRtxSsrc(uint32_t ssrc) { |
| rtc::CritScope lock(&send_critsect_); |
| ssrc_rtx_.emplace(ssrc); |
| } |
| |
| uint32_t RTPSender::RtxSsrc() const { |
| rtc::CritScope lock(&send_critsect_); |
| RTC_DCHECK(ssrc_rtx_); |
| return *ssrc_rtx_; |
| } |
| |
| void RTPSender::SetRtxPayloadType(int payload_type, |
| int associated_payload_type) { |
| rtc::CritScope lock(&send_critsect_); |
| RTC_DCHECK_LE(payload_type, 127); |
| RTC_DCHECK_LE(associated_payload_type, 127); |
| if (payload_type < 0) { |
| RTC_LOG(LS_ERROR) << "Invalid RTX payload type: " << payload_type << "."; |
| return; |
| } |
| |
| rtx_payload_type_map_[associated_payload_type] = payload_type; |
| } |
| |
| size_t RTPSender::TrySendRedundantPayloads(size_t bytes_to_send, |
| const PacedPacketInfo& pacing_info) { |
| { |
| rtc::CritScope lock(&send_critsect_); |
| if (!sending_media_) |
| return 0; |
| if ((rtx_ & kRtxRedundantPayloads) == 0) |
| return 0; |
| } |
| |
| int bytes_left = static_cast<int>(bytes_to_send); |
| while (bytes_left >= kMinPayloadPaddingBytes) { |
| std::unique_ptr<RtpPacketToSend> packet; |
| if (payload_padding_prefer_useful_packets_) { |
| packet = packet_history_.GetPayloadPaddingPacket(); |
| } else { |
| packet = packet_history_.GetBestFittingPacket(bytes_left); |
| } |
| |
| if (!packet) |
| break; |
| size_t payload_size = packet->payload_size(); |
| if (!PrepareAndSendPacket(std::move(packet), true, false, pacing_info)) |
| break; |
| bytes_left -= payload_size; |
| } |
| return bytes_to_send - bytes_left; |
| } |
| |
| size_t RTPSender::SendPadData(size_t bytes, |
| const PacedPacketInfo& pacing_info) { |
| size_t padding_bytes_in_packet; |
| size_t max_payload_size = max_packet_size_ - RtpHeaderLength(); |
| |
| if (audio_configured_) { |
| // Allow smaller padding packets for audio. |
| padding_bytes_in_packet = rtc::SafeClamp<size_t>( |
| bytes, kMinAudioPaddingLength, |
| rtc::SafeMin(max_payload_size, kMaxPaddingLength)); |
| } else { |
| // Always send full padding packets. This is accounted for by the |
| // RtpPacketSender, which will make sure we don't send too much padding even |
| // if a single packet is larger than requested. |
| // We do this to avoid frequently sending small packets on higher bitrates. |
| padding_bytes_in_packet = |
| rtc::SafeMin<size_t>(max_payload_size, kMaxPaddingLength); |
| } |
| size_t bytes_sent = 0; |
| while (bytes_sent < bytes) { |
| int64_t now_ms = clock_->TimeInMilliseconds(); |
| uint32_t ssrc; |
| uint32_t timestamp; |
| int64_t capture_time_ms; |
| uint16_t sequence_number; |
| int payload_type; |
| bool over_rtx; |
| { |
| rtc::CritScope lock(&send_critsect_); |
| if (!sending_media_) |
| break; |
| timestamp = last_rtp_timestamp_; |
| capture_time_ms = capture_time_ms_; |
| if (rtx_ == kRtxOff) { |
| if (last_payload_type_ == -1) |
| break; |
| // Without RTX we can't send padding in the middle of frames. |
| // For audio marker bits doesn't mark the end of a frame and frames |
| // are usually a single packet, so for now we don't apply this rule |
| // for audio. |
| if (!audio_configured_ && !last_packet_marker_bit_) { |
| break; |
| } |
| if (!ssrc_) { |
| RTC_LOG(LS_ERROR) << "SSRC unset."; |
| return 0; |
| } |
| |
| RTC_DCHECK(ssrc_); |
| ssrc = *ssrc_; |
| |
| sequence_number = sequence_number_; |
| ++sequence_number_; |
| payload_type = last_payload_type_; |
| over_rtx = false; |
| } else { |
| // Without abs-send-time or transport sequence number a media packet |
| // must be sent before padding so that the timestamps used for |
| // estimation are correct. |
| if (!media_has_been_sent_ && |
| !(rtp_header_extension_map_.IsRegistered(AbsoluteSendTime::kId) || |
| (rtp_header_extension_map_.IsRegistered( |
| TransportSequenceNumber::kId) && |
| transport_sequence_number_allocator_))) { |
| break; |
| } |
| // Only change change the timestamp of padding packets sent over RTX. |
| // Padding only packets over RTP has to be sent as part of a media |
| // frame (and therefore the same timestamp). |
| if (last_timestamp_time_ms_ > 0) { |
| timestamp += |
| (now_ms - last_timestamp_time_ms_) * kTimestampTicksPerMs; |
| capture_time_ms += (now_ms - last_timestamp_time_ms_); |
| } |
| if (!ssrc_rtx_) { |
| RTC_LOG(LS_ERROR) << "RTX SSRC unset."; |
| return 0; |
| } |
| RTC_DCHECK(ssrc_rtx_); |
| ssrc = *ssrc_rtx_; |
| sequence_number = sequence_number_rtx_; |
| ++sequence_number_rtx_; |
| payload_type = rtx_payload_type_map_.begin()->second; |
| over_rtx = true; |
| } |
| } |
| |
| RtpPacketToSend padding_packet(&rtp_header_extension_map_); |
| padding_packet.SetPayloadType(payload_type); |
| padding_packet.SetMarker(false); |
| padding_packet.SetSequenceNumber(sequence_number); |
| padding_packet.SetTimestamp(timestamp); |
| padding_packet.SetSsrc(ssrc); |
| |
| if (capture_time_ms > 0) { |
| padding_packet.SetExtension<TransmissionOffset>( |
| (now_ms - capture_time_ms) * kTimestampTicksPerMs); |
| } |
| padding_packet.SetExtension<AbsoluteSendTime>( |
| AbsoluteSendTime::MsTo24Bits(now_ms)); |
| PacketOptions options; |
| // Padding packets are never retransmissions. |
| options.is_retransmit = false; |
| bool has_transport_seq_num; |
| { |
| rtc::CritScope lock(&send_critsect_); |
| has_transport_seq_num = |
| UpdateTransportSequenceNumber(&padding_packet, &options.packet_id); |
| options.included_in_allocation = |
| has_transport_seq_num || force_part_of_allocation_; |
| options.included_in_feedback = has_transport_seq_num; |
| } |
| padding_packet.SetPadding(padding_bytes_in_packet); |
| if (has_transport_seq_num) { |
| AddPacketToTransportFeedback(options.packet_id, padding_packet, |
| pacing_info); |
| } |
| |
| if (!SendPacketToNetwork(padding_packet, options, pacing_info)) |
| break; |
| |
| bytes_sent += padding_bytes_in_packet; |
| UpdateRtpStats(padding_packet, over_rtx, false); |
| } |
| |
| return bytes_sent; |
| } |
| |
| void RTPSender::SetStorePacketsStatus(bool enable, uint16_t number_to_store) { |
| RtpPacketHistory::StorageMode mode; |
| if (enable) { |
| mode = legacy_packet_history_storage_mode_ |
| ? RtpPacketHistory::StorageMode::kStore |
| : RtpPacketHistory::StorageMode::kStoreAndCull; |
| } else { |
| mode = RtpPacketHistory::StorageMode::kDisabled; |
| } |
| packet_history_.SetStorePacketsStatus(mode, number_to_store); |
| } |
| |
| bool RTPSender::StorePackets() const { |
| return packet_history_.GetStorageMode() != |
| RtpPacketHistory::StorageMode::kDisabled; |
| } |
| |
| int32_t RTPSender::ReSendPacket(uint16_t packet_id) { |
| // Try to find packet in RTP packet history. Also verify RTT here, so that we |
| // don't retransmit too often. |
| absl::optional<RtpPacketHistory::PacketState> stored_packet = |
| packet_history_.GetPacketState(packet_id); |
| if (!stored_packet || stored_packet->pending_transmission) { |
| // Packet not found or already queued for retransmission, ignore. |
| return 0; |
| } |
| |
| const int32_t packet_size = static_cast<int32_t>(stored_packet->packet_size); |
| |
| // Skip retransmission rate check if not configured. |
| if (retransmission_rate_limiter_) { |
| // Check if we're overusing retransmission bitrate. |
| // TODO(sprang): Add histograms for nack success or failure reasons. |
| if (!retransmission_rate_limiter_->TryUseRate(packet_size)) { |
| return -1; |
| } |
| } |
| |
| if (paced_sender_) { |
| // Mark packet as being in pacer queue again, to prevent duplicates. |
| if (!packet_history_.SetPendingTransmission(packet_id)) { |
| // Packet has already been removed from history, return early. |
| return 0; |
| } |
| |
| paced_sender_->InsertPacket( |
| RtpPacketSender::kNormalPriority, stored_packet->ssrc, |
| stored_packet->rtp_sequence_number, stored_packet->capture_time_ms, |
| stored_packet->packet_size, true); |
| |
| return packet_size; |
| } |
| |
| std::unique_ptr<RtpPacketToSend> packet = |
| packet_history_.GetPacketAndSetSendTime(packet_id); |
| if (!packet) { |
| // Packet could theoretically time out between the first check and this one. |
| return 0; |
| } |
| |
| const bool rtx = (RtxStatus() & kRtxRetransmitted) > 0; |
| if (!PrepareAndSendPacket(std::move(packet), rtx, true, PacedPacketInfo())) |
| return -1; |
| |
| return packet_size; |
| } |
| |
| bool RTPSender::SendPacketToNetwork(const RtpPacketToSend& packet, |
| const PacketOptions& options, |
| const PacedPacketInfo& pacing_info) { |
| int bytes_sent = -1; |
| if (transport_) { |
| UpdateRtpOverhead(packet); |
| bytes_sent = transport_->SendRtp(packet.data(), packet.size(), options) |
| ? static_cast<int>(packet.size()) |
| : -1; |
| if (event_log_ && bytes_sent > 0) { |
| event_log_->Log(absl::make_unique<RtcEventRtpPacketOutgoing>( |
| packet, pacing_info.probe_cluster_id)); |
| } |
| } |
| // TODO(pwestin): Add a separate bitrate for sent bitrate after pacer. |
| if (bytes_sent <= 0) { |
| RTC_LOG(LS_WARNING) << "Transport failed to send packet."; |
| return false; |
| } |
| return true; |
| } |
| |
| void RTPSender::OnReceivedNack( |
| const std::vector<uint16_t>& nack_sequence_numbers, |
| int64_t avg_rtt) { |
| packet_history_.SetRtt(5 + avg_rtt); |
| for (uint16_t seq_no : nack_sequence_numbers) { |
| const int32_t bytes_sent = ReSendPacket(seq_no); |
| if (bytes_sent < 0) { |
| // Failed to send one Sequence number. Give up the rest in this nack. |
| RTC_LOG(LS_WARNING) << "Failed resending RTP packet " << seq_no |
| << ", Discard rest of packets."; |
| break; |
| } |
| } |
| } |
| |
| // Called from pacer when we can send the packet. |
| RtpPacketSendResult RTPSender::TimeToSendPacket( |
| uint32_t ssrc, |
| uint16_t sequence_number, |
| int64_t capture_time_ms, |
| bool retransmission, |
| const PacedPacketInfo& pacing_info) { |
| if (!SendingMedia()) { |
| return RtpPacketSendResult::kPacketNotFound; |
| } |
| |
| std::unique_ptr<RtpPacketToSend> packet; |
| if (ssrc == SSRC()) { |
| packet = packet_history_.GetPacketAndSetSendTime(sequence_number); |
| } else if (ssrc == FlexfecSsrc()) { |
| packet = flexfec_packet_history_.GetPacketAndSetSendTime(sequence_number); |
| } |
| |
| if (!packet) { |
| // Packet cannot be found or was resent too recently. |
| return RtpPacketSendResult::kPacketNotFound; |
| } |
| |
| return PrepareAndSendPacket( |
| std::move(packet), |
| retransmission && (RtxStatus() & kRtxRetransmitted) > 0, |
| retransmission, pacing_info) |
| ? RtpPacketSendResult::kSuccess |
| : RtpPacketSendResult::kTransportUnavailable; |
| } |
| |
| // Called from pacer when we can send the packet. |
| bool RTPSender::TrySendPacket(RtpPacketToSend* packet, |
| const PacedPacketInfo& pacing_info) { |
| RTC_DCHECK(packet); |
| |
| const uint32_t packet_ssrc = packet->Ssrc(); |
| const auto packet_type = packet->packet_type(); |
| RTC_DCHECK(packet_type.has_value()); |
| |
| PacketOptions options; |
| bool is_media = false; |
| bool is_rtx = false; |
| { |
| rtc::CritScope lock(&send_critsect_); |
| if (!sending_media_) { |
| return false; |
| } |
| |
| switch (*packet_type) { |
| case RtpPacketToSend::Type::kAudio: |
| case RtpPacketToSend::Type::kVideo: |
| if (packet_ssrc != ssrc_) { |
| return false; |
| } |
| is_media = true; |
| break; |
| case RtpPacketToSend::Type::kRetransmission: |
| case RtpPacketToSend::Type::kPadding: |
| // Both padding and retransmission must be on either the media or the |
| // RTX stream. |
| if (packet_ssrc == ssrc_rtx_) { |
| is_rtx = true; |
| } else if (packet_ssrc != ssrc_) { |
| return false; |
| } |
| break; |
| case RtpPacketToSend::Type::kForwardErrorCorrection: |
| // FlexFEC is on separate SSRC, ULPFEC uses media SSRC. |
| if (packet_ssrc != ssrc_ && packet_ssrc != flexfec_ssrc_) { |
| return false; |
| } |
| break; |
| } |
| |
| options.included_in_allocation = force_part_of_allocation_; |
| } |
| |
| // Bug webrtc:7859. While FEC is invoked from rtp_sender_video, and not after |
| // the pacer, these modifications of the header below are happening after the |
| // FEC protection packets are calculated. This will corrupt recovered packets |
| // at the same place. It's not an issue for extensions, which are present in |
| // all the packets (their content just may be incorrect on recovered packets). |
| // In case of VideoTimingExtension, since it's present not in every packet, |
| // data after rtp header may be corrupted if these packets are protected by |
| // the FEC. |
| int64_t now_ms = clock_->TimeInMilliseconds(); |
| int64_t diff_ms = now_ms - packet->capture_time_ms(); |
| packet->SetExtension<TransmissionOffset>(kTimestampTicksPerMs * diff_ms); |
| packet->SetExtension<AbsoluteSendTime>(AbsoluteSendTime::MsTo24Bits(now_ms)); |
| |
| if (packet->HasExtension<VideoTimingExtension>()) { |
| if (populate_network2_timestamp_) { |
| packet->set_network2_time_ms(now_ms); |
| } else { |
| packet->set_pacer_exit_time_ms(now_ms); |
| } |
| } |
| |
| // Downstream code actually uses this flag to distinguish between media and |
| // everything else. |
| options.is_retransmit = !is_media; |
| if (auto packet_id = packet->GetExtension<TransportSequenceNumber>()) { |
| options.packet_id = *packet_id; |
| options.included_in_feedback = true; |
| options.included_in_allocation = true; |
| AddPacketToTransportFeedback(*packet_id, *packet, pacing_info); |
| } |
| |
| options.application_data.assign(packet->application_data().begin(), |
| packet->application_data().end()); |
| |
| if (packet->packet_type() != RtpPacketToSend::Type::kPadding && |
| packet->packet_type() != RtpPacketToSend::Type::kRetransmission) { |
| UpdateDelayStatistics(packet->capture_time_ms(), now_ms, packet_ssrc); |
| UpdateOnSendPacket(options.packet_id, packet->capture_time_ms(), |
| packet_ssrc); |
| } |
| |
| const bool send_success = SendPacketToNetwork(*packet, options, pacing_info); |
| |
| // Put packet in retransmission history or update pending status even if |
| // actual sending fails. |
| if (is_media && packet->allow_retransmission()) { |
| packet_history_.PutRtpPacket(absl::make_unique<RtpPacketToSend>(*packet), |
| StorageType::kAllowRetransmission, now_ms); |
| } else if (packet->retransmitted_sequence_number()) { |
| packet_history_.MarkPacketAsSent(*packet->retransmitted_sequence_number()); |
| } |
| |
| if (send_success) { |
| UpdateRtpStats(*packet, is_rtx, |
| packet_type == RtpPacketToSend::Type::kRetransmission); |
| |
| rtc::CritScope lock(&send_critsect_); |
| media_has_been_sent_ = true; |
| } |
| |
| // Return true even if transport failed (will be handled by retransmissions |
| // instead in that case), so that PacketRouter does not have to iterate over |
| // all other RTP modules and fail to send there too. |
| return true; |
| } |
| |
| bool RTPSender::PrepareAndSendPacket(std::unique_ptr<RtpPacketToSend> packet, |
| bool send_over_rtx, |
| bool is_retransmit, |
| const PacedPacketInfo& pacing_info) { |
| RTC_DCHECK(packet); |
| int64_t capture_time_ms = packet->capture_time_ms(); |
| RtpPacketToSend* packet_to_send = packet.get(); |
| |
| std::unique_ptr<RtpPacketToSend> packet_rtx; |
| if (send_over_rtx) { |
| packet_rtx = BuildRtxPacket(*packet); |
| if (!packet_rtx) |
| return false; |
| packet_to_send = packet_rtx.get(); |
| } |
| |
| // Bug webrtc:7859. While FEC is invoked from rtp_sender_video, and not after |
| // the pacer, these modifications of the header below are happening after the |
| // FEC protection packets are calculated. This will corrupt recovered packets |
| // at the same place. It's not an issue for extensions, which are present in |
| // all the packets (their content just may be incorrect on recovered packets). |
| // In case of VideoTimingExtension, since it's present not in every packet, |
| // data after rtp header may be corrupted if these packets are protected by |
| // the FEC. |
| int64_t now_ms = clock_->TimeInMilliseconds(); |
| int64_t diff_ms = now_ms - capture_time_ms; |
| packet_to_send->SetExtension<TransmissionOffset>(kTimestampTicksPerMs * |
| diff_ms); |
| packet_to_send->SetExtension<AbsoluteSendTime>( |
| AbsoluteSendTime::MsTo24Bits(now_ms)); |
| |
| if (packet_to_send->HasExtension<VideoTimingExtension>()) { |
| if (populate_network2_timestamp_) { |
| packet_to_send->set_network2_time_ms(now_ms); |
| } else { |
| packet_to_send->set_pacer_exit_time_ms(now_ms); |
| } |
| } |
| |
| PacketOptions options; |
| // If we are sending over RTX, it also means this is a retransmission. |
| // E.g. RTPSender::TrySendRedundantPayloads calls PrepareAndSendPacket with |
| // send_over_rtx = true but is_retransmit = false. |
| options.is_retransmit = is_retransmit || send_over_rtx; |
| bool has_transport_seq_num; |
| { |
| rtc::CritScope lock(&send_critsect_); |
| has_transport_seq_num = |
| UpdateTransportSequenceNumber(packet_to_send, &options.packet_id); |
| options.included_in_allocation = |
| has_transport_seq_num || force_part_of_allocation_; |
| options.included_in_feedback = has_transport_seq_num; |
| } |
| if (has_transport_seq_num) { |
| AddPacketToTransportFeedback(options.packet_id, *packet_to_send, |
| pacing_info); |
| } |
| options.application_data.assign(packet_to_send->application_data().begin(), |
| packet_to_send->application_data().end()); |
| |
| if (!is_retransmit && !send_over_rtx) { |
| UpdateDelayStatistics(packet->capture_time_ms(), now_ms, packet->Ssrc()); |
| UpdateOnSendPacket(options.packet_id, packet->capture_time_ms(), |
| packet->Ssrc()); |
| } |
| |
| if (!SendPacketToNetwork(*packet_to_send, options, pacing_info)) |
| return false; |
| |
| { |
| rtc::CritScope lock(&send_critsect_); |
| media_has_been_sent_ = true; |
| } |
| UpdateRtpStats(*packet_to_send, send_over_rtx, is_retransmit); |
| return true; |
| } |
| |
| void RTPSender::UpdateRtpStats(const RtpPacketToSend& packet, |
| bool is_rtx, |
| bool is_retransmit) { |
| int64_t now_ms = clock_->TimeInMilliseconds(); |
| |
| rtc::CritScope lock(&statistics_crit_); |
| StreamDataCounters* counters = is_rtx ? &rtx_rtp_stats_ : &rtp_stats_; |
| |
| total_bitrate_sent_.Update(packet.size(), now_ms); |
| |
| if (counters->first_packet_time_ms == -1) |
| counters->first_packet_time_ms = now_ms; |
| |
| if (packet.packet_type() == RtpPacketToSend::Type::kForwardErrorCorrection) { |
| counters->fec.AddPacket(packet); |
| } |
| |
| if (is_retransmit) { |
| counters->retransmitted.AddPacket(packet); |
| nack_bitrate_sent_.Update(packet.size(), now_ms); |
| } |
| counters->transmitted.AddPacket(packet); |
| |
| if (rtp_stats_callback_) |
| rtp_stats_callback_->DataCountersUpdated(*counters, packet.Ssrc()); |
| } |
| |
| size_t RTPSender::TimeToSendPadding(size_t bytes, |
| const PacedPacketInfo& pacing_info) { |
| if (bytes == 0) |
| return 0; |
| size_t bytes_sent = TrySendRedundantPayloads(bytes, pacing_info); |
| if (bytes_sent < bytes) |
| bytes_sent += SendPadData(bytes - bytes_sent, pacing_info); |
| return bytes_sent; |
| } |
| |
| bool RTPSender::SendToNetwork(std::unique_ptr<RtpPacketToSend> packet, |
| StorageType storage) { |
| RTC_DCHECK(packet); |
| int64_t now_ms = clock_->TimeInMilliseconds(); |
| |
| uint32_t ssrc = packet->Ssrc(); |
| if (paced_sender_) { |
| uint16_t seq_no = packet->SequenceNumber(); |
| int64_t capture_time_ms = packet->capture_time_ms(); |
| size_t packet_size = |
| send_side_bwe_with_overhead_ ? packet->size() : packet->payload_size(); |
| auto packet_type = packet->packet_type(); |
| RTC_DCHECK(packet_type.has_value()); |
| if (ssrc == FlexfecSsrc()) { |
| // Store FlexFEC packets in the history here, so they can be found |
| // when the pacer calls TimeToSendPacket. |
| flexfec_packet_history_.PutRtpPacket(std::move(packet), storage, |
| absl::nullopt); |
| } else { |
| packet_history_.PutRtpPacket(std::move(packet), storage, absl::nullopt); |
| } |
| |
| paced_sender_->InsertPacket(PacketTypeToPriority(*packet_type), ssrc, |
| seq_no, capture_time_ms, packet_size, false); |
| return true; |
| } |
| |
| PacketOptions options; |
| options.is_retransmit = false; |
| |
| // |capture_time_ms| <= 0 is considered invalid. |
| // TODO(holmer): This should be changed all over Video Engine so that negative |
| // time is consider invalid, while 0 is considered a valid time. |
| if (packet->capture_time_ms() > 0) { |
| packet->SetExtension<TransmissionOffset>( |
| kTimestampTicksPerMs * (now_ms - packet->capture_time_ms())); |
| |
| if (populate_network2_timestamp_ && |
| packet->HasExtension<VideoTimingExtension>()) { |
| packet->set_network2_time_ms(now_ms); |
| } |
| } |
| packet->SetExtension<AbsoluteSendTime>(AbsoluteSendTime::MsTo24Bits(now_ms)); |
| |
| bool has_transport_seq_num; |
| { |
| rtc::CritScope lock(&send_critsect_); |
| has_transport_seq_num = |
| UpdateTransportSequenceNumber(packet.get(), &options.packet_id); |
| options.included_in_allocation = |
| has_transport_seq_num || force_part_of_allocation_; |
| options.included_in_feedback = has_transport_seq_num; |
| } |
| if (has_transport_seq_num) { |
| AddPacketToTransportFeedback(options.packet_id, *packet.get(), |
| PacedPacketInfo()); |
| } |
| options.application_data.assign(packet->application_data().begin(), |
| packet->application_data().end()); |
| |
| UpdateDelayStatistics(packet->capture_time_ms(), now_ms, packet->Ssrc()); |
| UpdateOnSendPacket(options.packet_id, packet->capture_time_ms(), |
| packet->Ssrc()); |
| |
| bool sent = SendPacketToNetwork(*packet, options, PacedPacketInfo()); |
| |
| if (sent) { |
| { |
| rtc::CritScope lock(&send_critsect_); |
| media_has_been_sent_ = true; |
| } |
| UpdateRtpStats(*packet, false, false); |
| } |
| |
| // To support retransmissions, we store the media packet as sent in the |
| // packet history (even if send failed). |
| if (storage == kAllowRetransmission) { |
| RTC_DCHECK_EQ(ssrc, SSRC()); |
| packet_history_.PutRtpPacket(std::move(packet), storage, now_ms); |
| } |
| |
| return sent; |
| } |
| |
| bool RTPSender::SendToNetwork(std::unique_ptr<RtpPacketToSend> packet, |
| StorageType storage, |
| RtpPacketSender::Priority priority) { |
| packet->set_packet_type(PacketPriorityToType(priority)); |
| return SendToNetwork(std::move(packet), storage); |
| } |
| |
| void RTPSender::RecomputeMaxSendDelay() { |
| max_delay_it_ = send_delays_.begin(); |
| for (auto it = send_delays_.begin(); it != send_delays_.end(); ++it) { |
| if (it->second >= max_delay_it_->second) { |
| max_delay_it_ = it; |
| } |
| } |
| } |
| |
| void RTPSender::UpdateDelayStatistics(int64_t capture_time_ms, |
| int64_t now_ms, |
| uint32_t ssrc) { |
| if (!send_side_delay_observer_ || capture_time_ms <= 0) |
| return; |
| |
| int avg_delay_ms = 0; |
| int max_delay_ms = 0; |
| uint64_t total_packet_send_delay_ms = 0; |
| { |
| rtc::CritScope cs(&statistics_crit_); |
| // Compute the max and average of the recent capture-to-send delays. |
| // The time complexity of the current approach depends on the distribution |
| // of the delay values. This could be done more efficiently. |
| |
| // Remove elements older than kSendSideDelayWindowMs. |
| auto lower_bound = |
| send_delays_.lower_bound(now_ms - kSendSideDelayWindowMs); |
| for (auto it = send_delays_.begin(); it != lower_bound; ++it) { |
| if (max_delay_it_ == it) { |
| max_delay_it_ = send_delays_.end(); |
| } |
| sum_delays_ms_ -= it->second; |
| } |
| send_delays_.erase(send_delays_.begin(), lower_bound); |
| if (max_delay_it_ == send_delays_.end()) { |
| // Removed the previous max. Need to recompute. |
| RecomputeMaxSendDelay(); |
| } |
| |
| // Add the new element. |
| RTC_DCHECK_GE(now_ms, static_cast<int64_t>(0)); |
| RTC_DCHECK_LE(now_ms, std::numeric_limits<int64_t>::max() / 2); |
| RTC_DCHECK_GE(capture_time_ms, static_cast<int64_t>(0)); |
| RTC_DCHECK_LE(capture_time_ms, std::numeric_limits<int64_t>::max() / 2); |
| int64_t diff_ms = now_ms - capture_time_ms; |
| RTC_DCHECK_GE(diff_ms, static_cast<int64_t>(0)); |
| RTC_DCHECK_LE(diff_ms, |
| static_cast<int64_t>(std::numeric_limits<int>::max())); |
| int new_send_delay = rtc::dchecked_cast<int>(now_ms - capture_time_ms); |
| SendDelayMap::iterator it; |
| bool inserted; |
| std::tie(it, inserted) = |
| send_delays_.insert(std::make_pair(now_ms, new_send_delay)); |
| if (!inserted) { |
| // TODO(terelius): If we have multiple delay measurements during the same |
| // millisecond then we keep the most recent one. It is not clear that this |
| // is the right decision, but it preserves an earlier behavior. |
| int previous_send_delay = it->second; |
| sum_delays_ms_ -= previous_send_delay; |
| it->second = new_send_delay; |
| if (max_delay_it_ == it && new_send_delay < previous_send_delay) { |
| RecomputeMaxSendDelay(); |
| } |
| } |
| if (max_delay_it_ == send_delays_.end() || |
| it->second >= max_delay_it_->second) { |
| max_delay_it_ = it; |
| } |
| sum_delays_ms_ += new_send_delay; |
| total_packet_send_delay_ms_ += new_send_delay; |
| total_packet_send_delay_ms = total_packet_send_delay_ms_; |
| |
| size_t num_delays = send_delays_.size(); |
| RTC_DCHECK(max_delay_it_ != send_delays_.end()); |
| max_delay_ms = rtc::dchecked_cast<int>(max_delay_it_->second); |
| int64_t avg_ms = (sum_delays_ms_ + num_delays / 2) / num_delays; |
| RTC_DCHECK_GE(avg_ms, static_cast<int64_t>(0)); |
| RTC_DCHECK_LE(avg_ms, |
| static_cast<int64_t>(std::numeric_limits<int>::max())); |
| avg_delay_ms = |
| rtc::dchecked_cast<int>((sum_delays_ms_ + num_delays / 2) / num_delays); |
| } |
| send_side_delay_observer_->SendSideDelayUpdated( |
| avg_delay_ms, max_delay_ms, total_packet_send_delay_ms, ssrc); |
| } |
| |
| void RTPSender::UpdateOnSendPacket(int packet_id, |
| int64_t capture_time_ms, |
| uint32_t ssrc) { |
| if (!send_packet_observer_ || capture_time_ms <= 0 || packet_id == -1) |
| return; |
| |
| send_packet_observer_->OnSendPacket(packet_id, capture_time_ms, ssrc); |
| } |
| |
| void RTPSender::ProcessBitrate() { |
| if (!bitrate_callback_) |
| return; |
| int64_t now_ms = clock_->TimeInMilliseconds(); |
| uint32_t ssrc; |
| { |
| rtc::CritScope lock(&send_critsect_); |
| if (!ssrc_) |
| return; |
| ssrc = *ssrc_; |
| } |
| |
| rtc::CritScope lock(&statistics_crit_); |
| bitrate_callback_->Notify(total_bitrate_sent_.Rate(now_ms).value_or(0), |
| nack_bitrate_sent_.Rate(now_ms).value_or(0), ssrc); |
| } |
| |
| size_t RTPSender::RtpHeaderLength() const { |
| rtc::CritScope lock(&send_critsect_); |
| size_t rtp_header_length = kRtpHeaderLength; |
| rtp_header_length += sizeof(uint32_t) * csrcs_.size(); |
| rtp_header_length += RtpHeaderExtensionSize(kFecOrPaddingExtensionSizes, |
| rtp_header_extension_map_); |
| return rtp_header_length; |
| } |
| |
| uint16_t RTPSender::AllocateSequenceNumber(uint16_t packets_to_send) { |
| rtc::CritScope lock(&send_critsect_); |
| uint16_t first_allocated_sequence_number = sequence_number_; |
| sequence_number_ += packets_to_send; |
| return first_allocated_sequence_number; |
| } |
| |
| void RTPSender::GetDataCounters(StreamDataCounters* rtp_stats, |
| StreamDataCounters* rtx_stats) const { |
| rtc::CritScope lock(&statistics_crit_); |
| *rtp_stats = rtp_stats_; |
| *rtx_stats = rtx_rtp_stats_; |
| } |
| |
| std::unique_ptr<RtpPacketToSend> RTPSender::AllocatePacket() const { |
| rtc::CritScope lock(&send_critsect_); |
| // TODO(danilchap): Find better motivator and value for extra capacity. |
| // RtpPacketizer might slightly miscalulate needed size, |
| // SRTP may benefit from extra space in the buffer and do encryption in place |
| // saving reallocation. |
| // While sending slightly oversized packet increase chance of dropped packet, |
| // it is better than crash on drop packet without trying to send it. |
| static constexpr int kExtraCapacity = 16; |
| auto packet = absl::make_unique<RtpPacketToSend>( |
| &rtp_header_extension_map_, max_packet_size_ + kExtraCapacity); |
| RTC_DCHECK(ssrc_); |
| packet->SetSsrc(*ssrc_); |
| packet->SetCsrcs(csrcs_); |
| // Reserve extensions, if registered, RtpSender set in SendToNetwork. |
| packet->ReserveExtension<AbsoluteSendTime>(); |
| packet->ReserveExtension<TransmissionOffset>(); |
| packet->ReserveExtension<TransportSequenceNumber>(); |
| |
| if (!mid_.empty()) { |
| // This is a no-op if the MID header extension is not registered. |
| packet->SetExtension<RtpMid>(mid_); |
| } |
| if (!rid_.empty()) { |
| // This is a no-op if the RID header extension is not registered. |
| packet->SetExtension<RtpStreamId>(rid_); |
| } |
| return packet; |
| } |
| |
| bool RTPSender::AssignSequenceNumber(RtpPacketToSend* packet) { |
| rtc::CritScope lock(&send_critsect_); |
| if (!sending_media_) |
| return false; |
| RTC_DCHECK(packet->Ssrc() == ssrc_); |
| packet->SetSequenceNumber(sequence_number_++); |
| |
| // Remember marker bit to determine if padding can be inserted with |
| // sequence number following |packet|. |
| last_packet_marker_bit_ = packet->Marker(); |
| // Remember payload type to use in the padding packet if rtx is disabled. |
| last_payload_type_ = packet->PayloadType(); |
| // Save timestamps to generate timestamp field and extensions for the padding. |
| last_rtp_timestamp_ = packet->Timestamp(); |
| last_timestamp_time_ms_ = clock_->TimeInMilliseconds(); |
| capture_time_ms_ = packet->capture_time_ms(); |
| return true; |
| } |
| |
| bool RTPSender::UpdateTransportSequenceNumber(RtpPacketToSend* packet, |
| int* packet_id) { |
| RTC_DCHECK(packet); |
| RTC_DCHECK(packet_id); |
| if (!rtp_header_extension_map_.IsRegistered(TransportSequenceNumber::kId)) |
| return false; |
| |
| if (!transport_sequence_number_allocator_) |
| return false; |
| |
| *packet_id = transport_sequence_number_allocator_->AllocateSequenceNumber(); |
| |
| if (!packet->SetExtension<TransportSequenceNumber>(*packet_id)) |
| return false; |
| |
| return true; |
| } |
| |
| void RTPSender::SetSendingMediaStatus(bool enabled) { |
| rtc::CritScope lock(&send_critsect_); |
| sending_media_ = enabled; |
| } |
| |
| bool RTPSender::SendingMedia() const { |
| rtc::CritScope lock(&send_critsect_); |
| return sending_media_; |
| } |
| |
| void RTPSender::SetAsPartOfAllocation(bool part_of_allocation) { |
| rtc::CritScope lock(&send_critsect_); |
| force_part_of_allocation_ = part_of_allocation; |
| } |
| |
| void RTPSender::SetTimestampOffset(uint32_t timestamp) { |
| rtc::CritScope lock(&send_critsect_); |
| timestamp_offset_ = timestamp; |
| } |
| |
| uint32_t RTPSender::TimestampOffset() const { |
| rtc::CritScope lock(&send_critsect_); |
| return timestamp_offset_; |
| } |
| |
| void RTPSender::SetSSRC(uint32_t ssrc) { |
| // This is configured via the API. |
| rtc::CritScope lock(&send_critsect_); |
| |
| if (ssrc_ == ssrc) { |
| return; // Since it's same ssrc, don't reset anything. |
| } |
| ssrc_.emplace(ssrc); |
| if (!sequence_number_forced_) { |
| sequence_number_ = random_.Rand(1, kMaxInitRtpSeqNumber); |
| } |
| } |
| |
| uint32_t RTPSender::SSRC() const { |
| rtc::CritScope lock(&send_critsect_); |
| RTC_DCHECK(ssrc_); |
| return *ssrc_; |
| } |
| |
| void RTPSender::SetRid(const std::string& rid) { |
| // RID is used in simulcast scenario when multiple layers share the same mid. |
| rtc::CritScope lock(&send_critsect_); |
| RTC_DCHECK_LE(rid.length(), RtpStreamId::kMaxValueSizeBytes); |
| rid_ = rid; |
| } |
| |
| void RTPSender::SetMid(const std::string& mid) { |
| // This is configured via the API. |
| rtc::CritScope lock(&send_critsect_); |
| mid_ = mid; |
| } |
| |
| absl::optional<uint32_t> RTPSender::FlexfecSsrc() const { |
| return flexfec_ssrc_; |
| } |
| |
| void RTPSender::SetCsrcs(const std::vector<uint32_t>& csrcs) { |
| RTC_DCHECK_LE(csrcs.size(), kRtpCsrcSize); |
| rtc::CritScope lock(&send_critsect_); |
| csrcs_ = csrcs; |
| } |
| |
| void RTPSender::SetSequenceNumber(uint16_t seq) { |
| rtc::CritScope lock(&send_critsect_); |
| sequence_number_forced_ = true; |
| sequence_number_ = seq; |
| } |
| |
| uint16_t RTPSender::SequenceNumber() const { |
| rtc::CritScope lock(&send_critsect_); |
| return sequence_number_; |
| } |
| |
| static void CopyHeaderAndExtensionsToRtxPacket(const RtpPacketToSend& packet, |
| RtpPacketToSend* rtx_packet) { |
| // Set the relevant fixed packet headers. The following are not set: |
| // * Payload type - it is replaced in rtx packets. |
| // * Sequence number - RTX has a separate sequence numbering. |
| // * SSRC - RTX stream has its own SSRC. |
| rtx_packet->SetMarker(packet.Marker()); |
| rtx_packet->SetTimestamp(packet.Timestamp()); |
| |
| // Set the variable fields in the packet header: |
| // * CSRCs - must be set before header extensions. |
| // * Header extensions - replace Rid header with RepairedRid header. |
| const std::vector<uint32_t> csrcs = packet.Csrcs(); |
| rtx_packet->SetCsrcs(csrcs); |
| for (int extension = kRtpExtensionNone + 1; |
| extension < kRtpExtensionNumberOfExtensions; ++extension) { |
| RTPExtensionType source_extension = |
| static_cast<RTPExtensionType>(extension); |
| // Rid header should be replaced with RepairedRid header |
| RTPExtensionType destination_extension = |
| source_extension == kRtpExtensionRtpStreamId |
| ? kRtpExtensionRepairedRtpStreamId |
| : source_extension; |
| |
| // Empty extensions should be supported, so not checking |source.empty()|. |
| if (!packet.HasExtension(source_extension)) { |
| continue; |
| } |
| |
| rtc::ArrayView<const uint8_t> source = |
| packet.FindExtension(source_extension); |
| |
| rtc::ArrayView<uint8_t> destination = |
| rtx_packet->AllocateExtension(destination_extension, source.size()); |
| |
| // Could happen if any: |
| // 1. Extension has 0 length. |
| // 2. Extension is not registered in destination. |
| // 3. Allocating extension in destination failed. |
| if (destination.empty() || source.size() != destination.size()) { |
| continue; |
| } |
| |
| std::memcpy(destination.begin(), source.begin(), destination.size()); |
| } |
| } |
| |
| std::unique_ptr<RtpPacketToSend> RTPSender::BuildRtxPacket( |
| const RtpPacketToSend& packet) { |
| std::unique_ptr<RtpPacketToSend> rtx_packet; |
| |
| // Add original RTP header. |
| { |
| rtc::CritScope lock(&send_critsect_); |
| if (!sending_media_) |
| return nullptr; |
| |
| RTC_DCHECK(ssrc_rtx_); |
| |
| // Replace payload type. |
| auto kv = rtx_payload_type_map_.find(packet.PayloadType()); |
| if (kv == rtx_payload_type_map_.end()) |
| return nullptr; |
| |
| rtx_packet = absl::make_unique<RtpPacketToSend>(&rtp_header_extension_map_, |
| max_packet_size_); |
| |
| rtx_packet->SetPayloadType(kv->second); |
| |
| // Replace sequence number. |
| rtx_packet->SetSequenceNumber(sequence_number_rtx_++); |
| |
| // Replace SSRC. |
| rtx_packet->SetSsrc(*ssrc_rtx_); |
| |
| CopyHeaderAndExtensionsToRtxPacket(packet, rtx_packet.get()); |
| |
| // The spec indicates that it is possible for a sender to stop sending mids |
| // once the SSRCs have been bound on the receiver. As a result the source |
| // rtp packet might not have the MID header extension set. |
| // However, the SSRC of the RTX stream might not have been bound on the |
| // receiver. This means that we should include it here. |
| // The same argument goes for the Repaired RID extension. |
| if (!mid_.empty()) { |
| // This is a no-op if the MID header extension is not registered. |
| rtx_packet->SetExtension<RtpMid>(mid_); |
| } |
| if (!rid_.empty()) { |
| // This is a no-op if the Repaired-RID header extension is not registered. |
| // rtx_packet->SetExtension<RepairedRtpStreamId>(rid_); |
| } |
| } |
| RTC_DCHECK(rtx_packet); |
| |
| uint8_t* rtx_payload = |
| rtx_packet->AllocatePayload(packet.payload_size() + kRtxHeaderSize); |
| if (rtx_payload == nullptr) |
| return nullptr; |
| |
| // Add OSN (original sequence number). |
| ByteWriter<uint16_t>::WriteBigEndian(rtx_payload, packet.SequenceNumber()); |
| |
| // Add original payload data. |
| auto payload = packet.payload(); |
| memcpy(rtx_payload + kRtxHeaderSize, payload.data(), payload.size()); |
| |
| // Add original application data. |
| rtx_packet->set_application_data(packet.application_data()); |
| |
| return rtx_packet; |
| } |
| |
| void RTPSender::RegisterRtpStatisticsCallback( |
| StreamDataCountersCallback* callback) { |
| rtc::CritScope cs(&statistics_crit_); |
| rtp_stats_callback_ = callback; |
| } |
| |
| StreamDataCountersCallback* RTPSender::GetRtpStatisticsCallback() const { |
| rtc::CritScope cs(&statistics_crit_); |
| return rtp_stats_callback_; |
| } |
| |
| uint32_t RTPSender::BitrateSent() const { |
| rtc::CritScope cs(&statistics_crit_); |
| return total_bitrate_sent_.Rate(clock_->TimeInMilliseconds()).value_or(0); |
| } |
| |
| void RTPSender::SetRtpState(const RtpState& rtp_state) { |
| rtc::CritScope lock(&send_critsect_); |
| sequence_number_ = rtp_state.sequence_number; |
| sequence_number_forced_ = true; |
| timestamp_offset_ = rtp_state.start_timestamp; |
| last_rtp_timestamp_ = rtp_state.timestamp; |
| capture_time_ms_ = rtp_state.capture_time_ms; |
| last_timestamp_time_ms_ = rtp_state.last_timestamp_time_ms; |
| media_has_been_sent_ = rtp_state.media_has_been_sent; |
| } |
| |
| RtpState RTPSender::GetRtpState() const { |
| rtc::CritScope lock(&send_critsect_); |
| |
| RtpState state; |
| state.sequence_number = sequence_number_; |
| state.start_timestamp = timestamp_offset_; |
| state.timestamp = last_rtp_timestamp_; |
| state.capture_time_ms = capture_time_ms_; |
| state.last_timestamp_time_ms = last_timestamp_time_ms_; |
| state.media_has_been_sent = media_has_been_sent_; |
| |
| return state; |
| } |
| |
| void RTPSender::SetRtxRtpState(const RtpState& rtp_state) { |
| rtc::CritScope lock(&send_critsect_); |
| sequence_number_rtx_ = rtp_state.sequence_number; |
| } |
| |
| RtpState RTPSender::GetRtxRtpState() const { |
| rtc::CritScope lock(&send_critsect_); |
| |
| RtpState state; |
| state.sequence_number = sequence_number_rtx_; |
| state.start_timestamp = timestamp_offset_; |
| |
| return state; |
| } |
| |
| void RTPSender::AddPacketToTransportFeedback( |
| uint16_t packet_id, |
| const RtpPacketToSend& packet, |
| const PacedPacketInfo& pacing_info) { |
| if (transport_feedback_observer_) { |
| size_t packet_size = packet.payload_size() + packet.padding_size(); |
| if (send_side_bwe_with_overhead_) { |
| packet_size = packet.size(); |
| } |
| |
| RtpPacketSendInfo packet_info; |
| packet_info.ssrc = SSRC(); |
| packet_info.transport_sequence_number = packet_id; |
| packet_info.has_rtp_sequence_number = true; |
| packet_info.rtp_sequence_number = packet.SequenceNumber(); |
| packet_info.length = packet_size; |
| packet_info.pacing_info = pacing_info; |
| transport_feedback_observer_->OnAddPacket(packet_info); |
| } |
| } |
| |
| void RTPSender::UpdateRtpOverhead(const RtpPacketToSend& packet) { |
| if (!overhead_observer_) |
| return; |
| size_t overhead_bytes_per_packet; |
| { |
| rtc::CritScope lock(&send_critsect_); |
| if (rtp_overhead_bytes_per_packet_ == packet.headers_size()) { |
| return; |
| } |
| rtp_overhead_bytes_per_packet_ = packet.headers_size(); |
| overhead_bytes_per_packet = rtp_overhead_bytes_per_packet_; |
| } |
| overhead_observer_->OnOverheadChanged(overhead_bytes_per_packet); |
| } |
| |
| int64_t RTPSender::LastTimestampTimeMs() const { |
| rtc::CritScope lock(&send_critsect_); |
| return last_timestamp_time_ms_; |
| } |
| |
| void RTPSender::SetRtt(int64_t rtt_ms) { |
| packet_history_.SetRtt(rtt_ms); |
| flexfec_packet_history_.SetRtt(rtt_ms); |
| } |
| |
| void RTPSender::OnPacketsAcknowledged( |
| rtc::ArrayView<const uint16_t> sequence_numbers) { |
| packet_history_.CullAcknowledgedPackets(sequence_numbers); |
| } |
| } // namespace webrtc |