Re: [Qemu-devel] [PATCH 1/1] parallels: add format spec

[Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>]

On 17.11.2015 18:54, Eric Blake wrote:
> On 11/16/2015 04:52 AM, Denis V. Lunev wrote:
>> From: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
>>
>> This specifies Parallels image format as implemented in Parallels Cloud
>> Server 6.10
> Are we the canonical location of the specification?  If not, do we risk
> getting out of sync with the canonical Parallels Cloud Server
> documentation, in which case, wouldn't it be better to point to a URL of
> the externally-maintained spec rather than duplicating it here?
>
>> +++ b/docs/specs/parallels.txt
>> @@ -0,0 +1,218 @@
>> += Parallels Expandable Image File Format =
>> +
> Is this document okay under the default GPLv2+ license, or does it need
> to explicitly call out a different license?
>
>
>> +== Header ==
>> +
>> +The header is placed at the start of an image and contains the following
>> +fields:
>> +
>> +    char      magic[16]
>> +              Must contain "WithoutFreeSpace" or "WithouFreSpacExt".
>> +
>> +    uint32    version
>> +              Must be 2.
>> +
> You may want to compare to the qcow2 spec, which also lists expected
> byte offsets for each field (rather than having to count how many
> earlier fields of which widths were specified).

I've compared qed spec with qcow2 spec and like the first one. What the 
need of specifying each offset? Creating a c-structure is simpler when 
you see types. and than offsetof and sizeof may be used if needed. 
Nobody will #define numeric offsets I think.



-- 
Best regards,
Vladimir
* now, @virtuozzo.com instead of @parallels.com. Sorry for this inconvenience.