[PATCH 3/3] Fix cli socket close due to io buffer full

[Kenth Eriksson]

On Tue, 2019-06-11 at 17:20 +0200, Ondrej Zajicek wrote:
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> On Tue, Jun 11, 2019 at 12:09:03PM +0200, Kenth Eriksson wrote:
> > The pointer rpos in the socket io module is only restored if the
> > rx_hook
> > callback returns 1. Previously the cli_rx hook always returned
> > 0. Guarantee by design that we return 1 if we are at the end of the
> > socket buffer.
> 
> I don't think this is correct, as that would reset buffer before its
> content is processed by cli_event().
> 
We can remove patch 3/3, but only if we have patch 1/3, else the socket
may be closed by the event loop reading 0 bytes. The socket read
(sk_read) happens in an inner while loop and the event list
(ev_run_list) in the outer while loop.

> Also, the issue is already fixed by patch 2/3.
> 
Well, patch 2/3 fixes the bug, but due to the asynchronous design where
io may happen before events I see this as robustness improvement. But
again, if we include patch 1/3 we can skip patch 3/3. 

> > Signed-off-by: Kenth Eriksson <kenth.eriksson at infinera.com>
> > ---
> >  sysdep/unix/main.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/sysdep/unix/main.c b/sysdep/unix/main.c
> > index cf5f4a3c..6a6d1d2b 100644
> > --- a/sysdep/unix/main.c
> > +++ b/sysdep/unix/main.c
> > @@ -422,7 +422,7 @@ static int
> >  cli_rx(sock *s, uint size UNUSED)
> >  {
> >    cli_kick(s->data);
> > -  return 0;
> > +  return s->rbuf+s->rbsize==s->rpos? 1 : 0;
> >  }
> > 
> >  static void
> > --
> > 2.21.0
> 
> --
> Elen sila lumenn' omentielvo
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> Ondrej 'Santiago' Zajicek (email: santiago at crfreenet.org)
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