Fix a deadlock in the new queueing logic.

[nageru] / player.cpp

diff --git a/player.cpp b/player.cpp
index fa4ea47d8615f72fcf48c7f863865f6760eba4f4..1432f04bad93d2b5df348755e0b7e5349d0f038a 100644 (file)
--- a/player.cpp
+++ b/player.cpp
@@ -73,7 +73,7 @@ wait_for_clip:
 
                if (!clip_ready) {
                        if (video_stream != nullptr) {
-                               video_stream->schedule_refresh_frame(pts);
+                               video_stream->schedule_refresh_frame(steady_clock::now(), pts, /*display_func=*/nullptr);
                        }
                        continue;
                }
@@ -85,7 +85,7 @@ wait_for_clip:
                        clip = current_clip;
                        stream_idx = current_stream_idx;
                }
-               steady_clock::time_point origin = steady_clock::now();
+               steady_clock::time_point origin = steady_clock::now();  // TODO: Add a 100 ms buffer for ramp-up?
                int64_t in_pts_origin = clip.pts_in;
 got_clip:
                int64_t out_pts_origin = pts;
@@ -180,13 +180,22 @@ got_clip:
                                break;
                        }
 
-                       // Sleep until the next frame start, or until there's a new clip we're supposed to play.
+                       // If the queue is full (which is really the state we'd like to be in),
+                       // wait until there's room for one more frame (ie., one was output from
+                       // VideoStream), or until or until there's a new clip we're supposed to play.
                        {
                                unique_lock<mutex> lock(queue_state_mu);
-                               new_clip_changed.wait_until(lock, next_frame_start, [this]{
+                               new_clip_changed.wait(lock, [this]{
+                                       if (video_stream != nullptr && num_queued_frames < max_queued_frames) {
+                                               return true;
+                                       }
                                        return new_clip_ready || override_stream_idx != -1;
                                });
                                if (new_clip_ready) {
+                                       if (video_stream != nullptr) {
+                                               video_stream->clear_queue();
+                                               num_queued_frames = 0;
+                                       }
                                        goto wait_for_clip;
                                }
                                if (override_stream_idx != -1) {
@@ -197,12 +206,24 @@ got_clip:
                        }
 
                        if (in_pts_lower == in_pts_upper) {
-                               destination->setFrame(primary_stream_idx, in_pts_lower, /*interpolated=*/false, secondary_stream_idx, secondary_pts, fade_alpha);
-                               if (video_stream != nullptr) {
+                               auto display_func = [this, primary_stream_idx, in_pts_lower, secondary_stream_idx, secondary_pts, fade_alpha]{
+                                       destination->setFrame(primary_stream_idx, in_pts_lower, /*interpolated=*/false, secondary_stream_idx, secondary_pts, fade_alpha);
+                                       unique_lock<mutex> lock(queue_state_mu);
+                                       assert(num_queued_frames > 0);
+                                       --num_queued_frames;
+                                       new_clip_changed.notify_all();
+                               };
+                               if (video_stream == nullptr) {
+                                       display_func();
+                               } else {
                                        if (secondary_stream_idx == -1) {
-                                               video_stream->schedule_original_frame(pts, primary_stream_idx, in_pts_lower);
+                                               video_stream->schedule_original_frame(next_frame_start, pts, display_func, primary_stream_idx, in_pts_lower);
+                                               unique_lock<mutex> lock(queue_state_mu);
+                                               ++num_queued_frames;
                                        } else {
-                                               video_stream->schedule_faded_frame(pts, primary_stream_idx, in_pts_lower, secondary_stream_idx, secondary_pts, fade_alpha);
+                                               bool ok = video_stream->schedule_faded_frame(next_frame_start, pts, display_func, primary_stream_idx, in_pts_lower, secondary_stream_idx, secondary_pts, fade_alpha);
+                                               unique_lock<mutex> lock(queue_state_mu);
+                                               if (ok) ++num_queued_frames;
                                        }
                                }
                                continue;
@@ -215,12 +236,24 @@ got_clip:
                        for (int64_t snap_pts : { in_pts_lower, in_pts_upper }) {
                                double snap_pts_as_frameno = (snap_pts - in_pts_origin) * output_framerate / TIMEBASE / speed;
                                if (fabs(snap_pts_as_frameno - frameno) < 0.01) {
-                                       destination->setFrame(primary_stream_idx, snap_pts, /*interpolated=*/false, secondary_stream_idx, secondary_pts, fade_alpha);
-                                       if (video_stream != nullptr) {
+                                       auto display_func = [this, primary_stream_idx, snap_pts, secondary_stream_idx, secondary_pts, fade_alpha]{
+                                               destination->setFrame(primary_stream_idx, snap_pts, /*interpolated=*/false, secondary_stream_idx, secondary_pts, fade_alpha);
+                                               unique_lock<mutex> lock(queue_state_mu);
+                                               assert(num_queued_frames > 0);
+                                               --num_queued_frames;
+                                               new_clip_changed.notify_all();
+                                       };
+                                       if (video_stream == nullptr) {
+                                               display_func();
+                                       } else {
                                                if (secondary_stream_idx == -1) {
-                                                       video_stream->schedule_original_frame(pts, primary_stream_idx, snap_pts);
+                                                       video_stream->schedule_original_frame(next_frame_start, pts, display_func, primary_stream_idx, snap_pts);
+                                                       unique_lock<mutex> lock(queue_state_mu);
+                                                       ++num_queued_frames;
                                                } else {
-                                                       video_stream->schedule_faded_frame(pts, primary_stream_idx, snap_pts, secondary_stream_idx, secondary_pts, fade_alpha);
+                                                       bool ok = video_stream->schedule_faded_frame(next_frame_start, pts, display_func, primary_stream_idx, snap_pts, secondary_stream_idx, secondary_pts, fade_alpha);
+                                                       unique_lock<mutex> lock(queue_state_mu);
+                                                       if (ok) ++num_queued_frames;
                                                }
                                        }
                                        in_pts_origin += snap_pts - in_pts;
@@ -245,10 +278,15 @@ got_clip:
                                assert(secondary_stream_idx == -1);
                                destination->setFrame(primary_stream_idx, in_pts_lower, /*interpolated=*/false);
                        } else {
-                               // Calculate the interpolated frame. When it's done, the destination
-                               // will be unblocked.
-                               destination->setFrame(primary_stream_idx, pts, /*interpolated=*/true, secondary_stream_idx, secondary_pts, fade_alpha);
-                               video_stream->schedule_interpolated_frame(pts, primary_stream_idx, in_pts_lower, in_pts_upper, alpha, secondary_stream_idx, secondary_pts, fade_alpha);
+                               auto display_func = [this, primary_stream_idx, pts, secondary_stream_idx, secondary_pts, fade_alpha]{
+                                       destination->setFrame(primary_stream_idx, pts, /*interpolated=*/true, secondary_stream_idx, secondary_pts, fade_alpha);
+                                       assert(num_queued_frames > 0);
+                                       --num_queued_frames;
+                                       new_clip_changed.notify_all();
+                               };
+                               bool ok = video_stream->schedule_interpolated_frame(next_frame_start, pts, display_func, primary_stream_idx, in_pts_lower, in_pts_upper, alpha, secondary_stream_idx, secondary_pts, fade_alpha);
+                               unique_lock<mutex> lock(queue_state_mu);
+                               if (ok) ++num_queued_frames;
                        }
                }