Maybe a deadlock between consumer and producer in player.c

[FredericHamel]

These are the sequences I do to freeze the cmus.

Sequence 1

1. Start playing a track
2. Press 'c' to pause the track.
3. Press 'v' to stop the track
   Expected result: the track is stop
   Actual result: the player is frozen

Sequence 2

1. Start playing a track
2. Press 'c' to pause
3. Press 'q' and quit.
   Expected result: cmus exits
   Actual result: cmus hang. Probably a deadlock between consumer and producer.

Note: cmus exit correctly without freezing if it is in the playing state or stopped state.
I tried to debug the consumer and producer threads, I notice one of the thread was stuck on either a mutex or condition variable.

---

1. uname -a:

Linux akaii-ryzen 5.16.16-artix1-1 #1 SMP PREEMPT Tue, 22 Mar 2022 12:25:22 +0000 x86_64 GNU/Linux

2. cmus --version:

cmus v2.9.1

3. cmus --plugins:

Input Plugins: /usr/lib/cmus/ip
  mad:
    Priority: 55
    File Types: mp3 mp2
    MIME Types: audio/mpeg audio/x-mp3 audio/x-mpeg
  opus:
    Priority: 50
    File Types: opus
    MIME Types:
  flac:
    Priority: 50
    File Types: flac fla
    MIME Types:
  modplug:
    Priority: 50
    File Types: mod s3m xm it 669 amf ams dbm dmf dsm far mdl med mtm okt ptm stm ult umx mt2 psm
    MIME Types:
  wavpack:
    Priority: 50
    File Types: wv
    MIME Types: audio/x-wavpack
  aac:
    Priority: 50
    File Types: aac
    MIME Types: audio/aac audio/aacp
  wav:
    Priority: 50
    File Types: wav
    MIME Types:
  vorbis:
    Priority: 50
    File Types: ogg oga ogx
    MIME Types: application/ogg audio/x-ogg
  cdio:
    Priority: 50
    File Types:
    MIME Types: x-content/audio-cdda
  mpc:
    Priority: 50
    File Types: mpc mpp mp+
    MIME Types: audio/x-musepack
  cue:
    Priority: 50
    File Types:
    MIME Types: application/x-cue
  ffmpeg:
    Priority: 30
    File Types: aa aac ac3 aif aifc aiff ape au fla flac m4a m4b mka mkv mp+ mp2 mp3 mp4 mpc mpp ogg opus shn tak tta wav webm wma wv
    MIME Types:

Output Plugins: /usr/lib/cmus/op
  pulse
  alsa
  oss
  jack
  ao

[FredericHamel]

The issue happen in op_close.The issue may be in pipewire-pulse.

[pgaskin]

The issue may be in pipewire-pulse.

I agree since this only started happening for me recently.

[FredericHamel]

I am not sure but I think the issue might have been solve in pipewire. I tried the above sequences and I got the expected result in both cases.
Can someone verify in their configuration if the problem is still happening?

[FredericHamel]

The problem is still there.

[philippemilink]

I encounter the same bug, reproductible with the following steps:

1. Start playing a track
2. Press 'c' to pause
3. Wait some time (usually more than a hour)
4. Press 'q' to quit.

The interface closes, but it takes several dozens of seconds for cmus to really exit.

[er888kh]

@philippemilink
Do you use pipewire? Can you check my workaround (#1172)? I had the same problem with earlier versions of pipewire but last time I checked there was no problem anymore.

[philippemilink]

@philippemilink Do you use pipewire? Can you check my workaround (#1172)? I had the same problem with earlier versions of pipewire but last time I checked there was no problem anymore.

Sorry for the late reply. Yes, I'm using pipewire and your workaround fixes the bug. Thanks!

[Dano507]

Getting the same UI freezing with the sequence Ctrl+s. The current song continues but the UI freezes completely except for when the window gets resized to a smaller size

Also confirming that the other sequences mentioned by @FredericHamel still cause freezing.

cmus version: cmus v2.10.0
uname -a: Linux hostname 5.19.5-arch1-1 #1 SMP PREEMPT_DYNAMIC Mon, 29 Aug 2022 15:51:05 +0000 x86_64 GNU/Linux
audio server: pipewire

[er888kh]

@Dano507
Are you sure this freezing is not related to software flow control?

[Dano507]

@Dano507 Are you sure this freezing is not related to software flow control?

Thanks for pointing that out @er888kh. My freezing sequence was related to software flow control and Ctrl+q unfroze the terminal.