Eric Blake <ebl...@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. 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.
