1 files changed, 98 insertions, 0 deletions
diff --git a/third_party/libwebrtc/video/video_receive_stream_timeout_tracker.cc b/third_party/libwebrtc/video/video_receive_stream_timeout_tracker.cc
new file mode 100644
index 0000000000..0409f26560
--- /dev/null
+++ b/third_party/libwebrtc/video/video_receive_stream_timeout_tracker.cc
@@ -0,0 +1,98 @@
+/*
+ *  Copyright (c) 2022 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 "video/video_receive_stream_timeout_tracker.h"
+
+#include <algorithm>
+#include <utility>
+
+#include "rtc_base/logging.h"
+
+namespace webrtc {
+
+VideoReceiveStreamTimeoutTracker::VideoReceiveStreamTimeoutTracker(
+    Clock* clock,
+    TaskQueueBase* const bookkeeping_queue,
+    const Timeouts& timeouts,
+    TimeoutCallback callback)
+    : clock_(clock),
+      bookkeeping_queue_(bookkeeping_queue),
+      timeouts_(timeouts),
+      timeout_cb_(std::move(callback)) {}
+
+VideoReceiveStreamTimeoutTracker::~VideoReceiveStreamTimeoutTracker() {
+  RTC_DCHECK(!timeout_task_.Running());
+}
+
+bool VideoReceiveStreamTimeoutTracker::Running() const {
+  return timeout_task_.Running();
+}
+
+TimeDelta VideoReceiveStreamTimeoutTracker::TimeUntilTimeout() const {
+  return std::max(timeout_ - clock_->CurrentTime(), TimeDelta::Zero());
+}
+
+void VideoReceiveStreamTimeoutTracker::Start(bool waiting_for_keyframe) {
+  RTC_DCHECK_RUN_ON(bookkeeping_queue_);
+  RTC_DCHECK(!timeout_task_.Running());
+  waiting_for_keyframe_ = waiting_for_keyframe;
+  TimeDelta timeout_delay = TimeoutForNextFrame();
+  last_frame_ = clock_->CurrentTime();
+  timeout_ = last_frame_ + timeout_delay;
+  timeout_task_ =
+      RepeatingTaskHandle::DelayedStart(bookkeeping_queue_, timeout_delay,
+                                        [this] { return HandleTimeoutTask(); });
+}
+
+void VideoReceiveStreamTimeoutTracker::Stop() {
+  timeout_task_.Stop();
+}
+
+void VideoReceiveStreamTimeoutTracker::SetWaitingForKeyframe() {
+  RTC_DCHECK_RUN_ON(bookkeeping_queue_);
+  waiting_for_keyframe_ = true;
+  TimeDelta timeout_delay = TimeoutForNextFrame();
+  if (clock_->CurrentTime() + timeout_delay < timeout_) {
+    Stop();
+    Start(waiting_for_keyframe_);
+  }
+}
+
+void VideoReceiveStreamTimeoutTracker::OnEncodedFrameReleased() {
+  RTC_DCHECK_RUN_ON(bookkeeping_queue_);
+  // If we were waiting for a keyframe, then it has just been released.
+  waiting_for_keyframe_ = false;
+  last_frame_ = clock_->CurrentTime();
+  timeout_ = last_frame_ + TimeoutForNextFrame();
+}
+
+TimeDelta VideoReceiveStreamTimeoutTracker::HandleTimeoutTask() {
+  RTC_DCHECK_RUN_ON(bookkeeping_queue_);
+  Timestamp now = clock_->CurrentTime();
+  // `timeout_` is hit and we have timed out. Schedule the next timeout at
+  // the timeout delay.
+  if (now >= timeout_) {
+    RTC_DLOG(LS_VERBOSE) << "Stream timeout at " << now;
+    TimeDelta timeout_delay = TimeoutForNextFrame();
+    timeout_ = now + timeout_delay;
+    timeout_cb_(now - last_frame_);
+    return timeout_delay;
+  }
+  // Otherwise, `timeout_` changed since we scheduled a timeout. Reschedule
+  // a timeout check.
+  return timeout_ - now;
+}
+
+void VideoReceiveStreamTimeoutTracker::SetTimeouts(Timeouts timeouts) {
+  RTC_DCHECK_RUN_ON(bookkeeping_queue_);
+  timeouts_ = timeouts;
+}
+
+}  // namespace webrtc