Re: [Ekiga-devel-list] Crashes and freezes in the account edition

[Julien Puydt <jpuydt free fr>]

Le 16/09/2012 22:19, Julien Puydt a écrit :
> I don't think it explains any crash or freeze, but it will at least
> avoid a discrepancy between the internal state of the account and what
> the user interface displays about it.

Sigh ; here is what the crash I see looks like :

(gdb) bt
#0  0x00007ffff3d2f957 in PWaitAndSignal::PWaitAndSignal(PSync const&, 
bool) () from /usr/lib/libopal.so.3.10-beta8
#1  0x00007ffff414d961 in SIPHandlersList::FindBy(std::map<PString, 
PSafePtr<SIPHandler, PSafePtrBase>, std::less<PString>, 
std::allocator<std::pair<PString const, PSafePtr<SIPHandler, 
PSafePtrBase> > > >&, PString const&, PSafetyMode) () from 
/usr/lib/libopal.so.3.10-beta8
#2  0x00007ffff414dc08 in 
SIPHandlersList::FindSIPHandlerByCallID(PString const&, PSafetyMode) () 
from /usr/lib/libopal.so.3.10-beta8
#3  0x00007ffff40f874a in SIPEndPoint::Unsubscribe(PString const&, 
PString const&, bool) () from /usr/lib/libopal.so.3.10-beta8
#4  0x00007ffff40f86de in 
SIPEndPoint::Unsubscribe(SIPSubscribe::PredefinedPackages, PString 
const&, bool) () from /usr/lib/libopal.so.3.10-beta8
#5  0x00007ffff4158c0a in SIP_Presentity::Close() () from 
/usr/lib/libopal.so.3.10-beta8
#6  0x00007ffff77bc5aa in Main (this=0xeb7940) at 
../../ekiga.git/lib/engine/components/opal/sip-endpoint.cpp:104
#7  Opal::Sip::subscriber::Main (this=0xeb7940) at 
../../ekiga.git/lib/engine/components/opal/sip-endpoint.cpp:92
#8  0x00007ffff32d2675 in PThread::PX_ThreadStart(void*) () from 
/usr/lib/libpt.so.2.10-beta8
#9  0x00007ffff1eceb50 in start_thread () from 
/lib/x86_64-linux-gnu/libpthread.so.0
#10 0x00007ffff1c1970d in clone () from /lib/x86_64-linux-gnu/libc.so.6
#11 0x0000000000000000 in ?? ()

It happens when I play in the account edition window, and is generally 
triggered by doing the following :
- activate the account so it tries to do something ;
- modify the account (let it active in the edit account window) ;
- disactivate the account from the button in the accounts window.

Here is part of the code of Opal::Account::disable, which is probably 
the culprit since it's clicking on the disabling which triggers the 
segfault :

  endpoint->unsubscribe (*this, presentity);
  if (presentity) {

    // FIXME : the following actions should probably be done by opal 
itself,
    // remembering what ekiga asked...
    for (std::set<std::string>::iterator iter = watched_uris.begin ();
         iter != watched_uris.end (); ++iter) {
      presentity->UnsubscribeFromPresence (PString (*iter));

Now that raises a few questions:

(1) I see a SIP_Presentity::Close in the backtrace, which is probably 
triggered by the call to endpoint->unsubscribe()... which as far as I 
understand, runs in parallel with the later code where we do 
presentity->UnsubscribeFromPresence... so if the presentity object has 
thread-safety issues, perhaps that explains the crash?

(2) what was this loop on watched_uris about anyway? [I don't remember...]

Snark