Re: why "in_sighandler"?

[Jan Djärv]

YAMAMOTO Mitsuharu skrev:
> > > > > > On Sun, 20 Aug 2006 18:37:30 +0200, "Jan D." <address@hidden> said:
>
> > I needed a variable that was only set when the signal handler is
> > running.
>
> I've got no response from you to my last message (*1) in the related
> thread.  So I'm not sure if you are for or against my suggestion about
> undoing `in_sighandler'-related changes and just changing the order of
> lock/unlock and BLOCK_INPUT/UNBLOCK_INPUT in the previous version of
> BLOCK_INPUT_ALLOC/UNBLOCK_INPUT_ALLOC as follows.
>
> #define BLOCK_INPUT_ALLOC                       \
>   do                                            \
>     {                                           \
>       if (pthread_self () == main_thread)       \
>         BLOCK_INPUT;                            \
>       pthread_mutex_lock (&alloc_mutex);        \
>     }                                           \
>   while (0)
> #define UNBLOCK_INPUT_ALLOC                     \
>   do                                            \
>     {                                           \
>       pthread_mutex_unlock (&alloc_mutex);      \
>       if (pthread_self () == main_thread)       \
>         UNBLOCK_INPUT;                          \
>     }                                           \
>   while (0)


I don't like it, because it assumes things are "probably OK" to run in the 
signal handler (i.e. pthread_mutex_lock/unlock).  I still think it might hang 
if a Gnome thread is in mutex_lock and a signal arrives and then the signal 
handler also enters mutex_lock.  It is one assumtion against another, neither 
suggestion is without flaws (we need SYNC_INPUT for that).

        Jan D.