Re: [Qemu-devel] [PATCH v1] hmp: 'info snapshots' not showing the id

[seeteena <s1seetee@linux.vnet.ibm.com>]

On 12/22/2017 01:07 PM, Markus Armbruster wrote:
> Eric Blake <eblake@redhat.com> writes:
>
>> On 12/19/2017 08:20 AM, Max Reitz wrote:
>>
>>> So there are three things:
>>>
>>> (1) We probably should not allow snapshot names that could be IDs.
>>> Easiest way to solve this: Names have to start with a non-digit.
>> Yes, that would be a nice change.  It is not strictly backwards
>> compatible (so we'd still have to cope with images that didn't follow
>> the rule, whether created by older qemu or by non-qemu implementations
>> of qcow2), but would alleviate a lot of confusion.
> I recommend to restrict ID strings to letters, digits, '-', '.', '_',
> starting with a letter.  Use id_wellformed() to check.
char *id_generate(IdSubSystems id) autogenates ID in the format eg- 
"#block146" with starting with '#' always.
restricting ID strings to use id_wellformed() means we need to force ID 
to start with letter.

#define ID_SPECIAL_CHAR '#' needs to change to (some letter)
#define ID_SPECIAL_CHAR 'A'

>
> If backward compatibility is an issue, deprecate offending IDs (with a
> suitable warning), and kill them off after the customary grace period.
>
> IDs embedded in image files and such you may have to keep working
> somehow indefinitely.
>