[libvirt] [PATCH 03/16] Add callback to virNetClient to be invoked on EOF

[Daniel P. Berrange]

On Thu, Jul 19, 2012 at 05:44:13PM +0800, Daniel Veillard wrote:
> On Thu, Jul 19, 2012 at 09:58:58AM +0100, Daniel P. Berrange wrote:
> > On Thu, Jul 19, 2012 at 04:18:33PM +0800, Daniel Veillard wrote:
> > > > @@ -1636,17 +1657,21 @@ void virNetClientIncomingEvent(virNetSocketPtr sock,
> > > >          VIR_DEBUG("%s : VIR_EVENT_HANDLE_HANGUP or "
> > > >                    "VIR_EVENT_HANDLE_ERROR encountered", __FUNCTION__);
> > > >          virNetSocketRemoveIOCallback(sock);
> > > > -        goto done;
> > > > +        goto eof;
> > > >      }
> > > >  
> > > >      if (events & VIR_EVENT_HANDLE_WRITABLE) {
> > > > -        if (virNetClientIOHandleOutput(client) < 0)
> > > > +        if (virNetClientIOHandleOutput(client) < 0) {
> > > >              virNetSocketRemoveIOCallback(sock);
> > > > +            goto eof;
> > > > +        }
> > > >      }
> > > >  
> > > >      if (events & VIR_EVENT_HANDLE_READABLE) {
> > > > -        if (virNetClientIOHandleInput(client) < 0)
> > > > +        if (virNetClientIOHandleInput(client) < 0) {
> > > >              virNetSocketRemoveIOCallback(sock);
> > > > +            goto eof;
> > > > +        }
> > > >      }
> > > 
> > > 
> > >   What about the case ?
> > >     if (client->haveTheBuck || client->wantClose) ?
> > > sure it's induced locally instead of getting raised by an eof
> > 
> > If either of those conditions are true, the virNetClientIncomingEvent
> > method should not be invoked - we just have a check for those at the
> > top as a sanity check. In the haveTheBuck==true case, this callback
> > will be activated again once the buck is released, so we'll deal with
> > EOF callbacks correctly.  In the wantClose==true case, we might miss
> > out invoking the EOF callback - I suspect this is only a problem if
> > the app code explicitly asked for a close itself, or if the keepalive
> > code triggers.
> > 
> > I'll check into this and if there are any fixes required, I'll do them
> > as a followup patch.
> 
>   Okay, ACK !

Actually based on Jiri's comments, I'll hold off pushing this and
post a new version.


Daniel
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