[libvirt] [PATCH] Improve error reporting when virsh console is run without a TTY

Eric Blake eblake at redhat.com
Fri Feb 24 15:42:38 UTC 2012


On 02/24/2012 08:13 AM, Daniel P. Berrange wrote:
> From: "Daniel P. Berrange" <berrange at redhat.com>
> 
> If attempting to run
> 
>   ssh root at somehost virsh console someguest
> 
> You'll get an error
> 
>   2012-02-15 13:11:47.683+0000: 4765: info : libvirt version: 0.9.10, package: 1.fc18 (Unknown, 2012-02-15-11:48:57, lettuce.camlab.fab.redhat.com)
>   2012-02-15 13:11:47.683+0000: 4765: error : vshRunConsole:320 : unable to get tty attributes: Invalid argument
>   Connected to domain f16x86_64
>   Escape character is ^]
> 
> There are several problems here
> 
>  - The actual error message is bad for users
>  - We shouldn't rely on VIR_ERROR for this case
>  - The prompt makes it look like we still connected
>    because we didn't flush stdout.

Did you also test 'ssh root at somehost virsh start --console someguest' to
make sure that the guest is started, but the console sanely refused?

> +++ b/tools/virsh.c
> @@ -838,8 +838,14 @@ cmdRunConsole(vshControl *ctl, virDomainPtr dom, const char *name)
>          goto cleanup;
>      }
>  
> +    if (!isatty(STDIN_FILENO)) {
> +        vshError(ctl, "%s", _("Cannot run interactive console without a controlling TTY"));
> +        goto cleanup;
> +    }
> +
>      vshPrintExtra(ctl, _("Connected to domain %s\n"), virDomainGetName(dom));
>      vshPrintExtra(ctl, _("Escape character is %s\n"), ctl->escapeChar);
> +    fflush(stdout);

At any rate, this looks sane. ACK.

Hmm, we ought to ask gnulib if they will relicense the isatty() module
(currently LGPLv3+); as isatty() on mingw has bugs worth working around.

-- 
Eric Blake   eblake at redhat.com    +1-919-301-3266
Libvirt virtualization library http://libvirt.org

-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 620 bytes
Desc: OpenPGP digital signature
URL: <http://listman.redhat.com/archives/libvir-list/attachments/20120224/5dbeb436/attachment-0001.sig>


More information about the libvir-list mailing list