Implement Cast Streaming mirroring, DLNA casting, daemon+GUI, and breadd integration

Builds out the full v1 scope: a vendored+patched openscreen subset for
low-latency Cast Streaming (Mirroring receiver 0F5096E8) alongside the
existing Cast V2/HLS and new DLNA/AVTransport casting paths, breadcastd's
Idle/Casting state machine with a private IPC socket, the breadcast GTK4
popup as a thin IPC client, and bread.cast.*/bread.command.cast.* breadd
integration (device discovery, start/stop, mirroring lifecycle events).
Also adds bakery/systemd/Forgejo CI packaging.

Validated end-to-end against a real Chromecast/Google TV: negotiated
Cast Streaming session, live pipeline playback, and daemon+GUI click-to-cast/
stop through the actual popup.

breadcast-caststream-sys/vendor/openscreen/cast/streaming/impl/statistics_analyzer.cc

@@ -0,0 +1,573 @@
+// Copyright 2023 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "cast/streaming/impl/statistics_analyzer.h"
+
+#include <algorithm>
+
+#include "cast/streaming/impl/statistics_common.h"
+#include "platform/base/trivial_clock_traits.h"
+#include "util/chrono_helpers.h"
+
+namespace openscreen::cast {
+
+using openscreen::clock_operators::operator<<;
+
+namespace {
+
+constexpr Clock::duration kAnalysisInterval = std::chrono::milliseconds(500);
+
+constexpr size_t kMaxRecentPacketInfoMapSize = 1000;
+constexpr size_t kMaxRecentFrameInfoMapSize = 200;
+
+constexpr int kDefaultMaxLatencyBucketMs = 800;
+constexpr int kDefaultBucketWidthMs = 20;
+
+double InMilliseconds(Clock::duration duration) {
+  return static_cast<double>(to_milliseconds(duration).count());
+}
+
+bool IsReceiverEvent(StatisticsEvent::Type event) {
+  return event == StatisticsEvent::Type::kFrameAckSent ||
+         event == StatisticsEvent::Type::kFrameDecoded ||
+         event == StatisticsEvent::Type::kFramePlayedOut ||
+         event == StatisticsEvent::Type::kPacketReceived;
+}
+
+}  // namespace
+
+StatisticsAnalyzer::StatisticsAnalyzer(
+    SenderStatsClient* stats_client,
+    ClockNowFunctionPtr now,
+    TaskRunner& task_runner,
+    std::unique_ptr<ClockOffsetEstimator> offset_estimator)
+    : stats_client_(stats_client),
+      offset_estimator_(std::move(offset_estimator)),
+      now_(now),
+      alarm_(now, task_runner),
+      start_time_(now()) {
+  statistics_collector_ = std::make_unique<StatisticsCollector>(now_);
+  InitHistograms();
+}
+
+StatisticsAnalyzer::~StatisticsAnalyzer() = default;
+
+void StatisticsAnalyzer::ScheduleAnalysis() {
+  Clock::time_point next_analysis_time = now_() + kAnalysisInterval;
+  alarm_.Schedule([this] { AnalyzeStatistics(); }, next_analysis_time);
+}
+
+void StatisticsAnalyzer::InitHistograms() {
+  for (auto& histogram : histograms_.audio) {
+    histogram =
+        SimpleHistogram(0, kDefaultMaxLatencyBucketMs, kDefaultBucketWidthMs);
+  }
+  for (auto& histogram : histograms_.video) {
+    histogram =
+        SimpleHistogram(0, kDefaultMaxLatencyBucketMs, kDefaultBucketWidthMs);
+  }
+}
+
+void StatisticsAnalyzer::AnalyzeStatistics() {
+  ProcessFrameEvents(statistics_collector_->TakeRecentFrameEvents());
+  ProcessPacketEvents(statistics_collector_->TakeRecentPacketEvents());
+  SendStatistics();
+  ScheduleAnalysis();
+}
+
+void StatisticsAnalyzer::SendStatistics() {
+  if (!stats_client_) {
+    return;
+  }
+
+  const Clock::time_point end_time = now_();
+  stats_client_->OnStatisticsUpdated(SenderStats{
+      .audio_statistics =
+          ConstructStatisticsList(end_time, StatisticsEvent::MediaType::kAudio),
+      .audio_histograms = histograms_.audio,
+      .video_statistics =
+          ConstructStatisticsList(end_time, StatisticsEvent::MediaType::kVideo),
+      .video_histograms = histograms_.video});
+}
+
+void StatisticsAnalyzer::ProcessFrameEvents(
+    const std::vector<FrameEvent>& frame_events) {
+  for (FrameEvent frame_event : frame_events) {
+    offset_estimator_->OnFrameEvent(frame_event);
+
+    FrameStatsMap& frame_stats_map = frame_stats_.Get(frame_event.media_type);
+    auto it = frame_stats_map.find(frame_event.type);
+    if (it == frame_stats_map.end()) {
+      frame_stats_map.insert(std::make_pair(
+          frame_event.type,
+          FrameStatsAggregate{.event_counter = 1,
+                              .sum_size = frame_event.size,
+                              .sum_delay = frame_event.delay_delta}));
+    } else {
+      ++(it->second.event_counter);
+      it->second.sum_size += frame_event.size;
+      it->second.sum_delay += frame_event.delay_delta;
+    }
+
+    RecordEventTimes(frame_event);
+    RecordFrameLatencies(frame_event);
+  }
+}
+
+void StatisticsAnalyzer::ProcessPacketEvents(
+    const std::vector<PacketEvent>& packet_events) {
+  for (PacketEvent packet_event : packet_events) {
+    offset_estimator_->OnPacketEvent(packet_event);
+
+    PacketStatsMap& packet_stats_map =
+        packet_stats_.Get(packet_event.media_type);
+    auto it = packet_stats_map.find(packet_event.type);
+    if (it == packet_stats_map.end()) {
+      packet_stats_map.insert(
+          std::make_pair(packet_event.type,
+                         PacketStatsAggregate{.event_counter = 1,
+                                              .sum_size = packet_event.size}));
+    } else {
+      ++(it->second.event_counter);
+      it->second.sum_size += packet_event.size;
+    }
+
+    RecordEventTimes(packet_event);
+    if (packet_event.type == StatisticsEvent::Type::kPacketSentToNetwork ||
+        packet_event.type == StatisticsEvent::Type::kPacketReceived) {
+      RecordPacketLatencies(packet_event);
+    } else if (packet_event.type ==
+               StatisticsEvent::Type::kPacketRetransmitted) {
+      // We only measure network latency for packets that are not retransmitted.
+      ErasePacketInfo(packet_event);
+    }
+  }
+}
+
+void StatisticsAnalyzer::RecordFrameLatencies(const FrameEvent& frame_event) {
+  FrameInfoMap& frame_infos = recent_frame_infos_.Get(frame_event.media_type);
+
+  // Event is too old, don't bother.
+  const bool map_is_full = frame_infos.size() == kMaxRecentFrameInfoMapSize;
+  if (map_is_full && frame_event.rtp_timestamp <= frame_infos.begin()->first) {
+    return;
+  }
+
+  auto it = frame_infos.find(frame_event.rtp_timestamp);
+  if (it == frame_infos.end()) {
+    if (map_is_full) {
+      frame_infos.erase(frame_infos.begin());
+    }
+
+    auto emplace_result =
+        frame_infos.emplace(frame_event.rtp_timestamp, FrameInfo{});
+    OSP_CHECK(emplace_result.second);
+    it = emplace_result.first;
+  }
+
+  switch (frame_event.type) {
+    case StatisticsEvent::Type::kFrameCaptureBegin:
+      it->second.capture_begin_time = frame_event.timestamp;
+      break;
+
+    case StatisticsEvent::Type::kFrameCaptureEnd: {
+      it->second.capture_end_time = frame_event.timestamp;
+      if (it->second.capture_begin_time != Clock::time_point::min()) {
+        const Clock::duration capture_latency =
+            frame_event.timestamp - it->second.capture_begin_time;
+        AddToLatencyAggregrate(StatisticType::kAvgCaptureLatencyMs,
+                               capture_latency, frame_event.media_type);
+        AddToHistogram(HistogramType::kCaptureLatencyMs, frame_event.media_type,
+                       InMilliseconds(capture_latency));
+      }
+    } break;
+
+    case StatisticsEvent::Type::kFrameEncoded: {
+      it->second.encode_end_time = frame_event.timestamp;
+      if (it->second.capture_end_time != Clock::time_point::min()) {
+        const Clock::duration encode_latency =
+            frame_event.timestamp - it->second.capture_end_time;
+        AddToLatencyAggregrate(StatisticType::kAvgEncodeTimeMs, encode_latency,
+                               frame_event.media_type);
+        AddToHistogram(HistogramType::kEncodeTimeMs, frame_event.media_type,
+                       InMilliseconds(encode_latency));
+      }
+    } break;
+
+    // Frame latency is the time from when the frame is encoded until the
+    // receiver ack for the frame is sent.
+    case StatisticsEvent::Type::kFrameAckSent: {
+      const auto adjusted_timestamp =
+          ToSenderTimestamp(frame_event.timestamp, frame_event.media_type);
+      if (!adjusted_timestamp) {
+        return;
+      }
+
+      if (it->second.encode_end_time != Clock::time_point::min()) {
+        const Clock::duration frame_latency =
+            *adjusted_timestamp - it->second.encode_end_time;
+        AddToLatencyAggregrate(StatisticType::kAvgFrameLatencyMs, frame_latency,
+                               frame_event.media_type);
+      }
+    } break;
+
+    case StatisticsEvent::Type::kFramePlayedOut: {
+      const auto adjusted_timestamp =
+          ToSenderTimestamp(frame_event.timestamp, frame_event.media_type);
+      if (!adjusted_timestamp) {
+        return;
+      }
+
+      if (it->second.capture_begin_time != Clock::time_point::min()) {
+        const Clock::duration e2e_latency =
+            *adjusted_timestamp - it->second.capture_begin_time;
+        AddToLatencyAggregrate(StatisticType::kAvgEndToEndLatencyMs,
+                               e2e_latency, frame_event.media_type);
+        AddToHistogram(HistogramType::kEndToEndLatencyMs,
+                       frame_event.media_type, InMilliseconds(e2e_latency));
+      }
+
+      // Positive delay means the frame is late.
+      if (frame_event.delay_delta > Clock::duration::zero()) {
+        session_stats_.Get(frame_event.media_type).late_frame_counter += 1;
+        AddToHistogram(HistogramType::kFrameLatenessMs, frame_event.media_type,
+                       InMilliseconds(frame_event.delay_delta));
+      }
+    } break;
+
+    default:
+      break;
+  }
+}
+
+void StatisticsAnalyzer::RecordPacketLatencies(
+    const PacketEvent& packet_event) {
+  FrameInfoMap& frame_infos = recent_frame_infos_.Get(packet_event.media_type);
+
+  // Queueing latency is the time from when a frame is encoded to when the
+  // packet is first sent.
+  if (packet_event.type == StatisticsEvent::Type::kPacketSentToNetwork) {
+    const auto it = frame_infos.find(packet_event.rtp_timestamp);
+
+    // We have an encode end time for a frame associated with this packet.
+    if (it != frame_infos.end()) {
+      const Clock::duration queueing_latency =
+          packet_event.timestamp - it->second.encode_end_time;
+      AddToLatencyAggregrate(StatisticType::kAvgQueueingLatencyMs,
+                             queueing_latency, packet_event.media_type);
+      AddToHistogram(HistogramType::kQueueingLatencyMs, packet_event.media_type,
+                     InMilliseconds(queueing_latency));
+    }
+  }
+
+  StatisticsAnalyzer::PacketKey key =
+      std::make_pair(packet_event.rtp_timestamp, packet_event.packet_id);
+  PacketInfoMap& packet_infos =
+      recent_packet_infos_.Get(packet_event.media_type);
+
+  const auto it = packet_infos.find(key);
+  if (it == packet_infos.end()) {
+    packet_infos.insert(
+        std::make_pair(key, PacketInfo{.timestamp = packet_event.timestamp,
+                                       .type = packet_event.type}));
+    if (packet_infos.size() > kMaxRecentPacketInfoMapSize) {
+      packet_infos.erase(packet_infos.begin());
+    }
+  } else {  // We know when this packet was sent, and when it arrived.
+    PacketInfo value = it->second;
+    StatisticsEvent::Type recorded_type = value.type;
+    Clock::time_point packet_sent_time;
+    Clock::time_point packet_received_time;
+    if (recorded_type == StatisticsEvent::Type::kPacketSentToNetwork &&
+        packet_event.type == StatisticsEvent::Type::kPacketReceived) {
+      packet_sent_time = value.timestamp;
+      packet_received_time = packet_event.timestamp;
+    } else if (recorded_type == StatisticsEvent::Type::kPacketReceived &&
+               packet_event.type ==
+                   StatisticsEvent::Type::kPacketSentToNetwork) {
+      packet_sent_time = packet_event.timestamp;
+      packet_received_time = value.timestamp;
+    } else {
+      return;
+    }
+
+    packet_infos.erase(it);
+
+    // Use the offset estimator directly since we are trying to calculate the
+    // average network latency.
+    const std::optional<Clock::duration> receiver_offset =
+        offset_estimator_->GetEstimatedOffset();
+    if (!receiver_offset) {
+      return;
+    }
+    packet_received_time -= *receiver_offset;
+
+    const auto latency = packet_received_time - packet_sent_time;
+    AddToLatencyAggregrate(StatisticType::kAvgNetworkLatencyMs, latency,
+                           packet_event.media_type);
+    AddToHistogram(HistogramType::kNetworkLatencyMs, packet_event.media_type,
+                   InMilliseconds(latency));
+
+    // Packet latency is the time from when a frame is encoded until when the
+    // packet is received.
+    const auto frame_it = frame_infos.find(packet_event.rtp_timestamp);
+    if (frame_it != frame_infos.end()) {
+      const Clock::duration packet_latency =
+          packet_received_time - frame_it->second.encode_end_time;
+      AddToLatencyAggregrate(StatisticType::kAvgPacketLatencyMs, packet_latency,
+                             packet_event.media_type);
+      AddToHistogram(HistogramType::kPacketLatencyMs, packet_event.media_type,
+                     InMilliseconds(packet_latency));
+    }
+  }
+}
+
+void StatisticsAnalyzer::RecordEventTimes(const StatisticsEvent& event) {
+  SessionStats& session_stats = session_stats_.Get(event.media_type);
+
+  Clock::time_point sender_timestamp = event.timestamp;
+  if (IsReceiverEvent(event.type)) {
+    const auto latency = offset_estimator_->GetEstimatedLatency();
+    if (latency) {
+      const Clock::time_point estimated_sent_time =
+          event.received_timestamp - *latency;
+      session_stats.last_response_received_time = std::max(
+          session_stats.last_response_received_time, estimated_sent_time);
+    }
+
+    const auto result = ToSenderTimestamp(event.timestamp, event.media_type);
+    if (!result) {
+      return;
+    }
+    sender_timestamp = *result;
+  }
+
+  session_stats.first_event_time =
+      std::min(session_stats.first_event_time, sender_timestamp);
+  session_stats.last_event_time =
+      std::max(session_stats.last_event_time, sender_timestamp);
+}
+
+void StatisticsAnalyzer::ErasePacketInfo(const PacketEvent& packet_event) {
+  const StatisticsAnalyzer::PacketKey key =
+      std::make_pair(packet_event.rtp_timestamp, packet_event.packet_id);
+  PacketInfoMap& packet_infos =
+      recent_packet_infos_.Get(packet_event.media_type);
+  packet_infos.erase(key);
+}
+
+void StatisticsAnalyzer::AddToLatencyAggregrate(
+    StatisticType latency_stat,
+    Clock::duration latency_delta,
+    StatisticsEvent::MediaType media_type) {
+  LatencyStatsMap& latency_stats = latency_stats_.Get(media_type);
+
+  auto it = latency_stats.find(latency_stat);
+  if (it == latency_stats.end()) {
+    latency_stats.insert(std::make_pair(
+        latency_stat, LatencyStatsAggregate{.data_point_counter = 1,
+                                            .sum_latency = latency_delta}));
+  } else {
+    ++(it->second.data_point_counter);
+    it->second.sum_latency += latency_delta;
+  }
+}
+
+void StatisticsAnalyzer::AddToHistogram(HistogramType histogram,
+                                        StatisticsEvent::MediaType media_type,
+                                        int64_t sample) {
+  histograms_.Get(media_type)[static_cast<int>(histogram)].Add(sample);
+}
+
+SenderStats::StatisticsList StatisticsAnalyzer::ConstructStatisticsList(
+    Clock::time_point end_time,
+    StatisticsEvent::MediaType media_type) {
+  SenderStats::StatisticsList stats_list;
+
+  PopulateFrameCountStat(StatisticsEvent::Type::kFrameDroppedByEncoder,
+                         StatisticType::kNumFramesDroppedByEncoder, media_type,
+                         stats_list);
+
+  PopulateFrameCountStat(StatisticsEvent::Type::kFrameCaptureEnd,
+                         StatisticType::kNumFramesCaptured, media_type,
+                         stats_list);
+
+  // kEnqueueFps
+  PopulateFpsStat(StatisticsEvent::Type::kFrameEncoded,
+                  StatisticType::kEnqueueFps, media_type, end_time, stats_list);
+
+  constexpr StatisticType kSupportedLatencyStats[] = {
+      StatisticType::kAvgEncodeTimeMs,      StatisticType::kAvgCaptureLatencyMs,
+      StatisticType::kAvgQueueingLatencyMs, StatisticType::kAvgNetworkLatencyMs,
+      StatisticType::kAvgPacketLatencyMs,   StatisticType::kAvgFrameLatencyMs,
+      StatisticType::kAvgEndToEndLatencyMs,
+  };
+  for (StatisticType type : kSupportedLatencyStats) {
+    PopulateAvgLatencyStat(type, media_type, stats_list);
+  }
+
+  // kEncodeRateKbps
+  PopulateFrameBitrateStat(StatisticsEvent::Type::kFrameEncoded,
+                           StatisticType::kEncodeRateKbps, media_type, end_time,
+                           stats_list);
+
+  // kPacketTransmissionRateKbps
+  PopulatePacketBitrateStat(StatisticsEvent::Type::kPacketSentToNetwork,
+                            StatisticType::kPacketTransmissionRateKbps,
+                            media_type, end_time, stats_list);
+
+  // kNumPacketsSent
+  PopulatePacketCountStat(StatisticsEvent::Type::kPacketSentToNetwork,
+                          StatisticType::kNumPacketsSent, media_type,
+                          stats_list);
+
+  // kNumPacketsReceived
+  PopulatePacketCountStat(StatisticsEvent::Type::kPacketReceived,
+                          StatisticType::kNumPacketsReceived, media_type,
+                          stats_list);
+
+  // kTimeSinceLastReceiverResponseMs
+  // kFirstEventTimeMs
+  // kLastEventTimeMs
+  // kNumLateFrames
+  PopulateSessionStats(media_type, end_time, stats_list);
+
+  return stats_list;
+}
+
+void StatisticsAnalyzer::PopulatePacketCountStat(
+    StatisticsEvent::Type event,
+    StatisticType stat,
+    StatisticsEvent::MediaType media_type,
+    SenderStats::StatisticsList& stats_list) {
+  PacketStatsMap& stats_map = packet_stats_.Get(media_type);
+
+  auto it = stats_map.find(event);
+  if (it != stats_map.end()) {
+    stats_list[static_cast<int>(stat)] = it->second.event_counter;
+  }
+}
+
+void StatisticsAnalyzer::PopulateFrameCountStat(
+    StatisticsEvent::Type event,
+    StatisticType stat,
+    StatisticsEvent::MediaType media_type,
+    SenderStats::StatisticsList& stats_list) {
+  FrameStatsMap& stats_map = frame_stats_.Get(media_type);
+
+  const auto it = stats_map.find(event);
+  if (it != stats_map.end()) {
+    stats_list[static_cast<int>(stat)] = it->second.event_counter;
+  }
+}
+
+void StatisticsAnalyzer::PopulateFpsStat(
+    StatisticsEvent::Type event,
+    StatisticType stat,
+    StatisticsEvent::MediaType media_type,
+    Clock::time_point end_time,
+    SenderStats::StatisticsList& stats_list) {
+  FrameStatsMap& stats_map = frame_stats_.Get(media_type);
+
+  const auto it = stats_map.find(event);
+  if (it != stats_map.end()) {
+    const Clock::duration duration = end_time - start_time_;
+    if (duration != Clock::duration::zero()) {
+      const int count = it->second.event_counter;
+      const double fps = (count / InMilliseconds(duration)) * 1000;
+      stats_list[static_cast<int>(stat)] = fps;
+    }
+  }
+}
+
+void StatisticsAnalyzer::PopulateAvgLatencyStat(
+    StatisticType stat,
+    StatisticsEvent::MediaType media_type,
+    SenderStats::StatisticsList& stats_list
+
+) {
+  LatencyStatsMap& latency_map = latency_stats_.Get(media_type);
+
+  const auto it = latency_map.find(stat);
+  if (it != latency_map.end() && it->second.data_point_counter > 0) {
+    const double avg_latency =
+        InMilliseconds(it->second.sum_latency) / it->second.data_point_counter;
+    stats_list[static_cast<int>(stat)] = avg_latency;
+  }
+}
+
+void StatisticsAnalyzer::PopulateFrameBitrateStat(
+    StatisticsEvent::Type event,
+    StatisticType stat,
+    StatisticsEvent::MediaType media_type,
+    Clock::time_point end_time,
+    SenderStats::StatisticsList& stats_list) {
+  FrameStatsMap& stats_map = frame_stats_.Get(media_type);
+
+  const auto it = stats_map.find(event);
+  if (it != stats_map.end()) {
+    const Clock::duration duration = end_time - start_time_;
+    if (duration != Clock::duration::zero()) {
+      const double kbps = it->second.sum_size / InMilliseconds(duration) * 8;
+      stats_list[static_cast<int>(stat)] = kbps;
+    }
+  }
+}
+
+void StatisticsAnalyzer::PopulatePacketBitrateStat(
+    StatisticsEvent::Type event,
+    StatisticType stat,
+    StatisticsEvent::MediaType media_type,
+    Clock::time_point end_time,
+    SenderStats::StatisticsList& stats_list) {
+  PacketStatsMap& stats_map = packet_stats_.Get(media_type);
+
+  auto it = stats_map.find(event);
+  if (it != stats_map.end()) {
+    const Clock::duration duration = end_time - start_time_;
+    if (duration != Clock::duration::zero()) {
+      const double kbps = it->second.sum_size / InMilliseconds(duration) * 8;
+      stats_list[static_cast<int>(stat)] = kbps;
+    }
+  }
+}
+
+void StatisticsAnalyzer::PopulateSessionStats(
+    StatisticsEvent::MediaType media_type,
+    Clock::time_point end_time,
+    SenderStats::StatisticsList& stats_list) {
+  SessionStats& session_stats = session_stats_.Get(media_type);
+
+  if (session_stats.first_event_time != Clock::time_point::min()) {
+    stats_list[static_cast<int>(StatisticType::kFirstEventTimeMs)] =
+        InMilliseconds(session_stats.first_event_time.time_since_epoch());
+  }
+
+  if (session_stats.last_event_time != Clock::time_point::min()) {
+    stats_list[static_cast<int>(StatisticType::kLastEventTimeMs)] =
+        InMilliseconds(session_stats.last_event_time.time_since_epoch());
+  }
+
+  if (session_stats.last_response_received_time != Clock::time_point::min()) {
+    stats_list[static_cast<int>(
+        StatisticType::kTimeSinceLastReceiverResponseMs)] =
+        InMilliseconds(end_time - session_stats.last_response_received_time);
+  }
+
+  stats_list[static_cast<int>(StatisticType::kNumLateFrames)] =
+      session_stats.late_frame_counter;
+}
+
+std::optional<Clock::time_point> StatisticsAnalyzer::ToSenderTimestamp(
+    Clock::time_point receiver_timestamp,
+    StatisticsEvent::MediaType media_type) const {
+  const std::optional<Clock::duration> receiver_offset =
+      offset_estimator_->GetEstimatedOffset();
+  if (!receiver_offset) {
+    return {};
+  }
+  return receiver_timestamp - *receiver_offset;
+}
+
+}  // namespace openscreen::cast