[libvirt] [PATCH] qemu: Report error on unexpected job stats type

[Michal Privoznik]

On 06/28/2018 04:30 PM, Jiri Denemark wrote:
> On Thu, Jun 28, 2018 at 15:45:12 +0200, Michal Privoznik wrote:
>> On 06/28/2018 03:29 PM, Jiri Denemark wrote:
>>> If we ever fail to properly set jobinfo->statsType,
>>> qemuDomainJobInfoToParams would return -1 without setting an error.
>>
>> Have you actually seen such error? Looks to me like both callers handle
>> this case properly.
> 
> Yes, when the code for destination migration filled in migration stats,
> but failed to set the stats type. As a result no stats were reported
> and the programmer's error was silently ignored.
> 
>>> Signed-off-by: Jiri Denemark <jdenemar at redhat.com>
>>> ---
>>>  src/qemu/qemu_domain.c | 6 ++++++
>>>  1 file changed, 6 insertions(+)
>>>
>>> diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c
>>> index fee44812c1..9afe705929 100644
>>> --- a/src/qemu/qemu_domain.c
>>> +++ b/src/qemu/qemu_domain.c
>>> @@ -730,6 +730,12 @@ qemuDomainJobInfoToParams(qemuDomainJobInfoPtr jobInfo,
>>>          return qemuDomainDumpJobInfoToParams(jobInfo, type, params, nparams);
>>>  
>>>      case QEMU_DOMAIN_JOB_STATS_TYPE_NONE:
>>> +        virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
>>> +                       _("invalid job statistics type"));
>>> +        break;
>>> +
>>> +    default:
>>> +        virReportEnumRangeError(qemuDomainJobStatsType, jobInfo->statsType);
>>>          break;
>>>      }
>>>  
>>>
>>
>> Can't we join TYPE_NONE and default together and just report enum range
>> error? What is the point in differentiating the two?
> 
> I did it in the first version of this patch (a long time ago), but
> Daniel explained that virReportEnumRangeError is supposed to be used
> only for unknown enum values. A different error should be used for known
> values which do not make sense in a specific place in the code.

Ah, okay.

ACK then.

Michal