[libvirt] [PATCH 3/3] virsh: Notify users about disconnects

[Jiri Denemark]

On Tue, Sep 22, 2015 at 13:21:18 +0200, Jiri Denemark wrote:
> On Mon, Sep 21, 2015 at 17:32:41 -0400, John Ferlan wrote:
> > 
> > 
> > On 09/17/2015 08:23 AM, Jiri Denemark wrote:
> > > After my "client rpc: Report proper error for keepalive disconnections"
> > > patch, virsh would no long print a warning when it closes a connection
> > > to a daemon after a keepalive timeout. Although the warning
> > > 
> > >     virsh # 2015-09-15 10:59:26.729+0000: 642080: info :
> > >     libvirt version: 1.2.19
> > >     2015-09-15 10:59:26.729+0000: 642080: warning :
> > >     virKeepAliveTimerInternal:143 : No response from client
> > >     0x7efdc0a46730 after 1 keepalive messages in 2 seconds
> > > 
> > > was pretty ugly, it was still useful. This patch brings the useful part
> > > back while making it much nicer:
> > > 
> > > virsh # error: Disconnected from qemu:///system due to keepalive timeout
> > > 
> > > Signed-off-by: Jiri Denemark <jdenemar at redhat.com>
> > > ---
> > >  tools/virsh.c | 35 ++++++++++++++++++++++++++++++++---
> > >  1 file changed, 32 insertions(+), 3 deletions(-)
> > > 
> > 
> > Patch series seems reasonable to me, except for one minor thing....
> > Found by my coverity checker...  Naturally
> > 
> > > diff --git a/tools/virsh.c b/tools/virsh.c
> > > index bb12dec..23436ea 100644
> > > --- a/tools/virsh.c
> > > +++ b/tools/virsh.c
> > > @@ -95,12 +95,41 @@ static int disconnected; /* we may have been disconnected */
> > >   * handler, just save the fact it was raised.
> > >   */
> > >  static void
> > > -virshCatchDisconnect(virConnectPtr conn ATTRIBUTE_UNUSED,
> > > +virshCatchDisconnect(virConnectPtr conn,
> > >                       int reason,
> > > -                     void *opaque ATTRIBUTE_UNUSED)
> > > +                     void *opaque)
> > >  {
> > > -    if (reason != VIR_CONNECT_CLOSE_REASON_CLIENT)
> > > +    if (reason != VIR_CONNECT_CLOSE_REASON_CLIENT) {
> > 
> > [1]
> > 
> > > +        vshControl *ctl = opaque;
> > > +        const char *str = "unknown reason";
> > > +        virErrorPtr error;
> > > +        char *uri;
> > > +
> > > +        error = virSaveLastError();
> > > +        uri = virConnectGetURI(conn);
> > > +
> > > +        switch ((virConnectCloseReason) reason) {
> > > +        case VIR_CONNECT_CLOSE_REASON_ERROR:
> > > +            str = N_("Disconnected from %s due to I/O error");
> > > +            break;
> > > +        case VIR_CONNECT_CLOSE_REASON_EOF:
> > > +            str = N_("Disconnected from %s due to end of file");
> > > +            break;
> > > +        case VIR_CONNECT_CLOSE_REASON_KEEPALIVE:
> > > +            str = N_("Disconnected from %s due to keepalive timeout");
> > > +            break;
> > > +        case VIR_CONNECT_CLOSE_REASON_CLIENT:
> > 
> > [1]        ^^^ Coverity complains about DEADCODE
> > 
> > Other than setting str = NULL and testing for it later, I'm not exactly
> > sure of the 'best' course of action.  e.g., if (str) { vshError();
> > disconnected++; }
> > 
> > I think if this is handled, then the series is ACK-able.
> 
> I think /* coverity[dead_error_begin] */ is the right solution in this
> case.

I pushed the series with this comment added above case
VIR_CONNECT_CLOSE_REASON_CLIENT.

Thanks,

Jirka