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Date: Sat, 11 Oct 2014 11:53:40 +0200
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Subject: Re: [Qemu-devel] [PATCH 2/3] qemu-io: Respect early image end for
 map
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To: =?windows-1252?Q?Beno=EEt_Canet?= <benoit.canet@irqsave.net>
Cc: Kevin Wolf <kwolf@redhat.com>, qemu-devel@nongnu.org, Stefan Hajnoczi <stefanha@redhat.com>

Am 10.10.2014 um 14:03 schrieb Beno=EEt Canet:
>> +        } else if (!num) {
>> +            error_report("Unexpected end of image");
>> +            return 0;
> I think this test can miss some case of Unexpected end of image.
>
> For example supose that in map_is_allocated the first bdrv_is_allocated
> actually succeed then *pnum =3D num. Then the bottom loop has exit on f=
ailure
> and the function return.
>
> in map_f &num is map_is_allocated *pnum so map_f's num !=3D 0 and this =
very test
> fails to see the unexpected end of image error.

num !=3D 0 because some sectors where successfully queried. In my opinion=
,=20
we should print the information about them we have. Then, the do-while=20
loop is repeated; and this time, map_is_allocated() either again returns=20
num > 0 (for whatever reason, but I'd be fine with it) or, more=20
probably, it'll be num =3D=3D 0 this time. So the error is not missed, it=
's=20
just printed one iteration later.

Max

> Best regards
>
> Beno=EEt
>
>>           }
>>  =20
>>           retstr =3D ret ? "    allocated" : "not allocated";
>> --=20
>> 2.0.4
>>
>>