On Wed, 10 Nov 2021 08:29:32 +0900
Takashi Yano wrote:
> On Wed, 10 Nov 2021 08:22:45 +0900
> Takashi Yano wrote:
> > On Tue, 9 Nov 2021 09:11:28 -0500
> > Ken Brown wrote:
> > > I'll have to reproduce the hang myself in order to test this (or maybe
> > > you could
> > > test it), but I now have a new guess: If the read call above keeps
> > > failing with
> > > EINTR, then we're in an infinite loop. This could happen because of the
> > > following code in fhandler_pipe::raw_read:
> > >
> > > DWORD waitret = cygwait (read_mtx, timeout);
> > > switch (waitret)
> > > {
> > > case WAIT_OBJECT_0:
> > > break;
> > > case WAIT_TIMEOUT:
> > > set_errno (EAGAIN);
> > > len = (size_t) -1;
> > > return;
> > > default:
> > > set_errno (EINTR);
> > > len = (size_t) -1;
> > > return;
> > > }
> > >
> > > Takashi, is EINTR really the appropriate errno in the default case?
> > > Isn't
> > > cygwait supposed to handle signals?
> >
> > I assume cygwait() returns WAIT_SIGNALED when signalled
> > by SIGINT, SIGTERM, SIGTSTP, etc... In this case, EINTR
> > should return I think.
> >
> > Is it wrong?
>
> Ah, if SA_RESTART is set, we should continue to read even
> if signalled...
So, should this be like following?
restart_wait_read_mtx:
DWORD waitret = cygwait (read_mtx, timeout, cw_sig_eintr);
switch (waitret)
{
case WAIT_OBJECT_0:
break;
case WAIT_TIMEOUT:
set_errno (EAGAIN);
len = (size_t) -1;
return;
case WAIT_SIGNALED:
if (_my_tls.call_signal_handler ())
goto restart_wait_read_mtx;
set_errno (EINTR);
len = (size_t) -1;
return;
default:
/* Should not reach here. */
__seterrno ();
len = (size_t) -1;
return;
}
--
Takashi Yano <takashi.y...@nifty.ne.jp>
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