On 12/07/10 21:36, Stefan Hajnoczi wrote:
> On Tue, Dec 7, 2010 at 5:39 PM, <jes.soren...@redhat.com> wrote:
>> // The size for the image must always be specified, with one exception:
>> // If we are using a backing file, we can obtain the size from there
>> - if (get_option_parameter(param, BLOCK_OPT_SIZE)->value.n == -1) {
>> -
>> + if (get_option_parameter(param, BLOCK_OPT_SIZE)->value.n == 0) {
>> QEMUOptionParameter *backing_file =
>> get_option_parameter(param, BLOCK_OPT_BACKING_FILE);
>> QEMUOptionParameter *backing_fmt =
>
> Today it is possible to create 0 byte sized images. Your patch will
> change that:
> If there is a backing file, then the size will be taken from the backing file.
> If there is no backing file, then an error about missing size will be
> printed, even though a size of 0 has been given.
>
> I don't think 0 sized images are very useful, but I'm not sure we
> should make this change.
The old code also fails if there is no size, except for when a backing
file is present.
I hadn't thought of the zero sized file, but on the other hand, I don't
see it being useful.
I would like to make this change to get the option handling cleaned up
as it allows me to refactor the code in img_create().
Cheers,
Jes
