[PlanetCCRMA] help fix qtractor crash on bus changing/configuration (3021645)

[Niels Mayer]

In another thread I mentioned:
> You can get it to change the number of channels, but it may crash
> jackd in the process. Requiring a qtractor restart after you save the
> file/template with the multichannel audio bus. This is a known bug:
> http://sourceforge.net/tracker/?func=detail&atid=733076&aid=3021645&group_id=135501
> that is still present in subversion.
>

Rui needs help reproducing this bug: "Crash after changing audio bus -
ID: 3021645)"
http://sourceforge.net/tracker/?func=detail&atid=733076&aid=3021645&group_id=135501

If interested, please enable gdb coredumps and send backtraces in
reply-all to this thread.

To do this you need

(1) Build from subversion a debug build:

http://qtractor.sourceforge.net/qtractor-downloads.html#SVN and
compile using
http://qtractor.sourceforge.net/qtractor-index.html#Installation
but with "/configure --enable-debug"

(2) do command ' bash -c "ulimit -c" ' If it returns 0, do ' bash -c
"ulimit -c unlimited" '

(3)  Run Qtractor and attempt to reproduce the problem:

In my case, the crash, however, isn't happeing in qtractor, it's
happeing in jack2 -- which in this case for simplicitly, I'm letting
qtractor startup w/o qjackctl.
( jack-audio-connection-kit-1.9.4-1.fc12.ccrma.x86_64 )

Below is the qtractor log output that happens after I go to "VIew ->
Buses..." , select "Audio Master" -> "Audio" -> "Channels" --> "12" ->
"Update"

If I were to save the template containing these settings, I could
startup qtractor in 12 channel mode. It's the updating of master bus
from 2-> 12 that causes jackd to die, takes everything else down with
it, and forces you to save and restart qtractor.

.............

13:05:35.220 Open session: "Untitled1".
13:05:36.689 Session started.
Cannot connect to server socket err = Connection refused
Cannot connect to server socket
Cannot connect to server socket err = Connection refused
Cannot connect to server socket
no message buffer overruns
no message buffer overruns
jackdmp 1.9.4
Copyright 2001-2005 Paul Davis and others.
Copyright 2004-2009 Grame.
jackdmp comes with ABSOLUTELY NO WARRANTY
This is free software, and you are welcome to redistribute it
under certain conditions; see the file COPYING for details
JACK server starting in realtime mode with priority 60
audio_reservation_init
Acquire audio card Audio2
creating alsa driver ... hw:M66|hw:M66|256|2|44100|0|0|hwmon|hwmeter|-|32bit
Using ALSA driver ICE1712 running on card 2 - M Audio Delta 66 at 0xec00, irq 21
configuring for 44100Hz, period = 256 frames (5.8 ms), buffer = 2 periods
ALSA: final selected sample format for capture: 32bit integer little-endian
ALSA: use 2 periods for capture
ALSA: final selected sample format for playback: 32bit integer little-endian

ALSA: use 2 periods for playback
port created: Midi-Through:midi/playback_1
port created: Midi-Through:midi/capture_1
port created: MT4:midi/playback_1
port created: MT4:midi/capture_1
port created: MT4:midi/playback_2
port created: MT4:midi/capture_2
port created: MT4:midi/playback_3
port created: MT4:midi/capture_3
port created: MT4:midi/capture_4
port created: MT4:midi/capture_5
port created: BCD3000:midi/playback_1
port created: BCD3000:midi/capture_1
port created: UM-2:midi/playback_1
port created: UM-2:midi/capture_1
port created: UM-2:midi/playback_2
port created: UM-2:midi/capture_2
port created: QmidiNet:midi/playback_1
port created: QmidiNet:midi/capture_1
port created: QmidiNet:midi/playback_2
port created: QmidiNet:midi/capture_2
port created: QMidiRoute:midi/capture_1
port created: QMidiRoute:midi/playback_2
port created: QMidiRoute:midi/playback_3
port created: Qtractor:midi/playback_1
port created: Qtractor:midi/playback_2
port created: Qtractor:midi/capture_2
port created: Qtractor:midi/playback_3

port created: Qtractor:midi/playback_4
port created: Qtractor:midi/capture_4
port created: Qtractor:midi/playback_5
port created: Qtractor:midi/capture_5

13:05:37.169 Audio connections change.
13:05:37.176 MIDI connections change.
13:05:51.799 The audio engine has been shutdown. Make sure the JACK
audio server (jackd) is up and running and then restart session.
JackClientSocket::Read time out
JackClientSocket::Read time out
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Could not read result type = 1
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Could not read result type = 1
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Could not read result type = 1

Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Could not read result type = 1
JackSocketClientChannel read fail
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Could not read result type = 7
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Could not read result type = 2
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Could not read result type = 2
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Could not read result type = 2
Cannot write socket fd = 12 err = Broken pipe

Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Could not read result type = 2
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Could not read result type = 2
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Could not read result type = 2
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Could not read result type = 2
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Could not read result type = 2
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Could not read result type = 2
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe

Cannot write socket fd = 12 err = Broken pipe
Could not read result type = 2
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Could not read result type = 2
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Could not read result type = 2
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Could not read result type = 2
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Could not read result type = 2
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Could not read result type = 2
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe

Cannot write socket fd = 12 err = Broken pipe
Could not read result type = 2
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Could not read result type = 2
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Could not read result type = 2
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Could not read result type = 2
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Could not read result type = 2
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Cannot write socket fd = 12 err = Broken pipe
Could not read result type = 2

13:05:51.971 Audio connections change.
.....................

Above happening off current subversion trunk:  "At revision 1597."

Niels
http://nielsmayer.com