Re: [ECOS] sigwait not returning

["N.Suresh" <nsuresh at cdotb dot ernet dot in>]

Hi,
   We tried delivering the signal to a sigwait () call:
       *) Using alarm () function --- Working.
       *) pthread_kill () function ---  Working.

   It looks like only in the case of timer_create () case, the sigwait 
is not returning.

   We traced the call and found that in the following piece of code, 
signal_sigwait condition variable's queue is empty.
   So it is not calling the broadcast method which will wake the 
sigwait thread.
   It is releasing the thread, and in next POSIX_ASR call, the 
cyg_deliver_signals function is calling  _exit because there
    is no signal handler registered for this thread.
  
    All these functions are getting called only if i unmask the signal 
in the thread before calling the sigwait.
    Otherwise the check in the alarm_action function whether thread is 
accepting this signal will fail.
  
   Are we on the right path of debugging?

regards

<cut signal.cxx>

    sigaddset( &sig_pending, signo );

       // Wake up any threads in sigsuspend() and sigwait().

       if (!signal_sigwait.get_queue()->empty())

       {

           signal_sigwait.broadcast();

       } 
       else

       {

           cyg_posix_pthread_release_thread( &sig_pending );

       }

</cut signal.cxx>

  
N.Suresh wrote:

> > Try this instead:
> >
> >     pthread_sigmask (SIG_BLOCK, &set, (sigset_t*)NULL);
> >
> >  
> I had tried this before. It didn't work.
> So i tried to unblock all the signals in the thread itself.
>
> If i don't do this, in alarm_action () function, the check whether any 
> thread is waiting for the signal is failing and
> it is simply returning.
>
> regards

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