godot: Microphone recording doesn't work on Linux with official builds

@FeralBytes the change might be in the fa26a551. After reverting that in Master the recording started working for me. The changes look pretty innocent and I cannot tell just by looking what is the problem. Any thoughts @marcelofg55.

Edit: Adding this line seems to be enough fix it for me. Race condition / synchronization problem perhaps?

--- drivers/pulseaudio/audio_driver_pulseaudio.cpp	(revision 21dec856f2a7482fc69e18ffc60f64e90e10fcc5)
+++ drivers/pulseaudio/audio_driver_pulseaudio.cpp	(date 1577224764136)
@@ -669,6 +669,8 @@
 			break;
 	}
 
+	print_verbose("PulseAudio: detected " + itos(pa_rec_map.channels) + " input channels");
+	
 	pa_sample_spec spec;
 
 	spec.format = PA_SAMPLE_S16LE;

I was looking closely at the code and I’m no expert at C++ or threaded stuff. When set_recording_active is set to false, it never waits for the thread to finish. The code inside the thread _io_thread_process does know when to stop processing, but it seems like that function is still being called since the thread never finishes.

Also _io_thread_process really just calls _update_buffer. Though what’s strange is that another function called _update also calls _update_buffer as well. I’m not sure where _update gets called from but it never checks if the recording has stopped.

Maybe I can try to clone the repo and test to see if there is any issues there.

Over 3 years later and this is still happening on Godot 4.01 stable. Recorded audio is silent every time. The length of the recording is accurate but the data is all 0s. You can clearly hear yourself with the Record bus unmuted, so imo the issue lies somewhere within the set_recording_active() and/or get_recording() functions. I tried to figure it out but I am not equipped enough to figure it out. Please help anyone 😢

@Calinou 3.2 beta 4 is broken, also 3.1.1 is broken Also 3.1 Stable does not work. A what stage of 3.1 was it added at Alpha? Ah 3.1 Alpha1 works. I then tested Beta 1 and it was broken. I then worked backwards and found that even 3.1. Alpha2 was broken.

So a change between 3.1 Alpha1 and 3.1Alpha2 broke mic recording for many versions of Linux.

EDIT: Tested in both Linux Mint 19.2 and 19.3, same result.

More testing, i was reading through the source code and wanted to get more details. I run the test project in verbose mode, and all of the sudden, it starts to work.

For some unknown reason, verbose mode, fixes the issue? And running without verbose mode, brings the issue back.

All I can assume here and what I’m guessing, is that the verbose printing is delaying something long enough for it to work?

EDIT: Oh wait, that’s what everyone above has said as well, didn’t check that part, whoops.

I could finally reproduce this too, it seems like official builds don’t work but local builds do. Likely an issue with the different PulseAudio versions used on the official buildsystem and on user systems.