[Bug 34983] arts cannot work with esd

[Francois-Denis Gonthier]

Public bug reported:
https://launchpad.net/malone/bugs/34983

Affects: arts (Ubuntu)
       Severity: Normal
       Priority: (none set)
         Status: Unconfirmed

Description:
arts cannot function with esd in Dapper, probably because of a recent
upgrade in arts or KDE package that I could trace.

Symptoms: arts simply blocks.  It became pretty bad for me because arts
was set to run with esd in the control panel.  Since it did not respond
after starting, it gets automatically restarted, I ended up with a ton
of artsd process doing nothing in background.

To reproduce:

kill any artsd process currently running.
in one terminal, start esd.
in another terminal, start artsd: artsd -a esd -l0

you will get this:

artsd version is 1.5.1
gsl: using Unix98 pthreads directly for mutexes and conditions
[artsd:  4826] SoundServerStartup --> got lock
virtualize StereoVolumeControl
audio format is 44100 Hz, 16 bits, 2 channels
addDirectory(/usr/lib/mcop,)
addDirectory(/usr/lib/mcop/Amarok,Amarok)
addDirectory(/usr/lib/mcop/Arts,Arts)
addDirectory(/usr/lib/mcop/Arts/Environment,Arts::Environment)
addDirectory(/home/neumann/.mcop/trader-cache,)
Arts::MidiManager registered successfully.
[artsd:  4826] SoundServerStartup <-- released lock

at this point, artsd is blocked and can't be stopped with ctrl+c.
Stopping esd will stop artsd.

Stack trace of artsd at the moment it is blocked:

#0  0x00002aaaab66d602 in write () from /lib/libc.so.6
#1  0x00002aaaaae05d5f in Arts::AudioIOESD::write ()
   from /usr/lib/libartsflow.so.1
#2  0x00002aaaaae0deda in Arts::AudioSubSystem::handleIO ()
   from /usr/lib/libartsflow.so.1
#3  0x00002aaaaae21430 in Arts::Synth_PLAY_impl::notifyIO ()
   from /usr/lib/libartsflow.so.1
#4  0x00002aaaabbe3010 in Arts::StdIOManager::processOneEvent ()
   from /usr/lib/libmcop.so.1
#5  0x00002aaaabbdcce6 in Arts::StdIOManager::run () from /usr/lib/libmcop.so.1
#6  0x0000000000416b0d in ?? ()
#7  0x00002aaaab5cf49b in __libc_start_main () from /lib/libc.so.6
#8  0x000000000040ee1a in ?? ()
#9  0x00007fffff99fe78 in ?? ()
#10 0x000000000000001c in ?? ()
#11 0x0000000000000004 in ?? ()
#12 0x00007fffff9a08c4 in ?? ()
#13 0x00007fffff9a08d3 in ?? ()
#14 0x00007fffff9a08d6 in ?? ()
#15 0x00007fffff9a08da in ?? ()
#16 0x0000000000000000 in ?? ()

I will attach an strace output after this message.