[libvirt] [PATCH 02/20] remote: Don't hard code the feature VIR_DRV_FEATURE_REMOTE_CLOSE_CALLBACK as available

[Marc Hartmayer]

On Wed, Mar 21, 2018 at 07:57 AM +0100, Marc Hartmayer <mhartmay at linux.vnet.ibm.com> wrote:
> On Mon, Mar 19, 2018 at 04:06 PM +0100, "Daniel P. Berrangé" <berrange at redhat.com> wrote:
>> On Thu, Mar 08, 2018 at 01:20:25PM +0100, Marc Hartmayer wrote:
>>> Don't assume that the feature VIR_DRV_FEATURE_REMOTE_CLOSE_CALLBACK is
>>> available for every driver used for the connection.
>>
>> The very definition of the virConnectRegisterCloseCallback() API is that
>> it will always succeed.   What varies is that some driver connections
>> may never fail and so the close callback will never be invoked. The actual
>> registration of the callback will always succeed regardless of which driver
>> is in use. So it is correct to report the VIR_DRV_FEATURE_REMOTE_CLOSE_CALLBACK
>> as always supported regardless of driver.
>
> Okay. So how can we deal with the situation in patch 18 if we cannot
> differentiate between 'callback was “really” registered' and only the
> call was 'successful'? If it’s not really registered nobody will free
> the callback data. This was also the cause for the fix: ce35122cfe:
> "daemon: fixup refcounting in close callback handling".
>
> Thanks in advance.

Polite ping.

>
>>
>>
>> Regards,
>> Daniel
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> --
> Beste Grüße / Kind regards
>    Marc Hartmayer
>
> IBM Deutschland Research & Development GmbH
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--
Beste Grüße / Kind regards
   Marc Hartmayer

IBM Deutschland Research & Development GmbH
Vorsitzende des Aufsichtsrats: Martina Koederitz
Geschäftsführung: Dirk Wittkopp
Sitz der Gesellschaft: Böblingen
Registergericht: Amtsgericht Stuttgart, HRB 243294