[libvirt] [PATCH 1/2] xen: add error handling to UUID parsing

[Guido Günther]

On Thu, Oct 06, 2011 at 03:55:48PM -0400, Laine Stump wrote:
> On 10/06/2011 01:36 PM, Guido Günther wrote:
> >Hi Eric,
> >On Thu, Oct 06, 2011 at 10:50:46AM -0600, Eric Blake wrote:
> >>
> >>These three errors should probably all be changed away from
> >>VIR_ERR_INTERNAL_ERROR into something more useful, but I'm not sure
> >>whether that would be VIR_ERR_CONF_SYNTAX,
> >>VIR_ERR_CONFIG_UNSUPPORTED, or something else.
> >I was uncertain about the error codes too, that's why I kept
> >VIR_ERR_INTERNAL_ERROR as used by other functions in this file. I'd
> >opt for VIR_ERR_CONF_SYNTAX.
> 
> We really need to agree on a policy on which code to use for which
> type of errors, write it down, then go through the code and correct
> everything that's wrong. INTERNAL_ERROR is used *a lot* in XML
> parsing where it obviously shouldn't be. Much of it is probably code
> written before the CONFIG_UNSUPPORTED, XML_ERROR, and CONF_SYNTAX
> codes were added, but I'd wager just as much is due to people
> writing new code who look to the existing code for guidelines (I
> know I've done this a lot, and continue to be confused about which
> code to use in a lot of cases - heck, this is the first I've noticed
> CONF_SYNTAX, and I'm not sure when it would be appropriate to use
> that vs. XML_ERROR).

We're not parsing XML here but xen configuration so CONF_SYNTAX fits
better. When parsing XML XML_ERROR makes more sense but you're right
that's mostly guessing at the moment.
Cheers,
 -- Guido