Revert of Use TaskQueue in IncomingVideoStream

webrtc/common_video/incoming_video_stream.cc

Index: webrtc/common_video/incoming_video_stream.cc
diff --git a/webrtc/common_video/incoming_video_stream.cc b/webrtc/common_video/incoming_video_stream.cc
index b88892d9672ddfa18ad675b6f02d9383af8e54c0..c1f61d1cfb87c94b55f57246a4ceaf684f98526d 100644
--- a/webrtc/common_video/incoming_video_stream.cc
+++ b/webrtc/common_video/incoming_video_stream.cc
@@ -10,8 +10,6 @@
 
 #include "webrtc/common_video/include/incoming_video_stream.h"
 
-#include <memory>
-
 #include "webrtc/base/timeutils.h"
 #include "webrtc/common_video/video_render_frames.h"
 #include "webrtc/system_wrappers/include/critical_section_wrapper.h"
@@ -19,62 +17,87 @@
 
 namespace webrtc {
 namespace {
-const char kIncomingQueueName[] = "IncomingVideoStream";
-}
-
-// Capture by moving (std::move) into a lambda isn't possible in C++11
-// (supported in C++14). This class provides the functionality of what would be
-// something like (inside OnFrame):
-// VideoFrame frame(video_frame);
-// incoming_render_queue_.PostTask([this, frame = std::move(frame)](){
-//   if (render_buffers_.AddFrame(std::move(frame)) == 1)
-//     Dequeue();
-// });
-class IncomingVideoStream::NewFrameTask : public rtc::QueuedTask {
- public:
-  NewFrameTask(IncomingVideoStream* stream, VideoFrame frame)
-      : stream_(stream), frame_(std::move(frame)) {}
-
- private:
-  bool Run() override {
-    RTC_DCHECK(rtc::TaskQueue::IsCurrent(kIncomingQueueName));
-    if (stream_->render_buffers_.AddFrame(std::move(frame_)) == 1)
-      stream_->Dequeue();
-    return true;
-  }
-
-  IncomingVideoStream* stream_;
-  VideoFrame frame_;
-};
+const int kEventStartupTimeMs = 10;
+const int kEventMaxWaitTimeMs = 100;
+}  // namespace
 
 IncomingVideoStream::IncomingVideoStream(
     int32_t delay_ms,
     rtc::VideoSinkInterface<VideoFrame>* callback)
-    : render_buffers_(delay_ms),
-      callback_(callback),
-      incoming_render_queue_(kIncomingQueueName,
-                             rtc::TaskQueue::Priority::HIGH) {}
+    : incoming_render_thread_(&IncomingVideoStreamThreadFun,
+                              this,
+                              "IncomingVideoStreamThread",
+                              rtc::kRealtimePriority),
+      deliver_buffer_event_(EventTimerWrapper::Create()),
+      external_callback_(callback),
+      render_buffers_(new VideoRenderFrames(delay_ms)) {
+  RTC_DCHECK(external_callback_);
+
+  render_thread_checker_.DetachFromThread();
+
+  deliver_buffer_event_->StartTimer(false, kEventStartupTimeMs);
+  incoming_render_thread_.Start();
+}
 
 IncomingVideoStream::~IncomingVideoStream() {
   RTC_DCHECK(main_thread_checker_.CalledOnValidThread());
+
+  {
+    rtc::CritScope cs(&buffer_critsect_);
+    render_buffers_.reset();
+  }
+
+  deliver_buffer_event_->Set();
+  incoming_render_thread_.Stop();
+  deliver_buffer_event_->StopTimer();
 }
 
 void IncomingVideoStream::OnFrame(const VideoFrame& video_frame) {
   RTC_CHECK_RUNS_SERIALIZED(&decoder_race_checker_);
-  RTC_DCHECK(!incoming_render_queue_.IsCurrent());
-  incoming_render_queue_.PostTask(
-      std::unique_ptr<rtc::QueuedTask>(new NewFrameTask(this, video_frame)));
+  // Hand over or insert frame.
+  rtc::CritScope csB(&buffer_critsect_);
+  if (render_buffers_->AddFrame(video_frame) == 1) {
+    deliver_buffer_event_->Set();
+  }
 }
 
-void IncomingVideoStream::Dequeue() {
-  RTC_DCHECK(incoming_render_queue_.IsCurrent());
-  rtc::Optional<VideoFrame> frame_to_render = render_buffers_.FrameToRender();
-  if (frame_to_render)
-    callback_->OnFrame(*frame_to_render);
+// static
+void IncomingVideoStream::IncomingVideoStreamThreadFun(void* obj) {
+  static_cast<IncomingVideoStream*>(obj)->IncomingVideoStreamProcess();
+}
 
-  if (render_buffers_.HasPendingFrames()) {
-    uint32_t wait_time = render_buffers_.TimeToNextFrameRelease();
-    incoming_render_queue_.PostDelayedTask([this]() { Dequeue(); }, wait_time);
+void IncomingVideoStream::IncomingVideoStreamProcess() {
+  RTC_DCHECK_RUN_ON(&render_thread_checker_);
+
+  while (true) {
+    if (kEventError != deliver_buffer_event_->Wait(kEventMaxWaitTimeMs)) {
+      // Get a new frame to render and the time for the frame after this one.
+      rtc::Optional<VideoFrame> frame_to_render;
+      uint32_t wait_time;
+      {
+        rtc::CritScope cs(&buffer_critsect_);
+        if (!render_buffers_.get()) {
+          // Terminating
+          return;
+        }
+
+        frame_to_render = render_buffers_->FrameToRender();
+        wait_time = render_buffers_->TimeToNextFrameRelease();
+      }
+
+      // Set timer for next frame to render.
+      if (wait_time > kEventMaxWaitTimeMs) {
+        wait_time = kEventMaxWaitTimeMs;
+      }
+
+      deliver_buffer_event_->StartTimer(false, wait_time);
+
+      if (frame_to_render) {
+        external_callback_->OnFrame(*frame_to_render);
+      }
+    } else {
+      RTC_NOTREACHED();
+    }
   }
 }