[libvirt] [PATCH] schema: Allow spaces in paths

[Michal Privoznik]

On 11.08.2016 19:43, Cole Robinson wrote:
> On 08/11/2016 12:02 PM, Michal Privoznik wrote:
>> Since ages filesystems allowed to have space characters in
>> filenames and even directory names. In fact, on all major
>> filesystems out there you can have whatever character you like
>> except NULL. There's no reason why we should forbid users to not
>> have spaces in their filenames. Moreover, if we do that only on
>> RNG schema level while our XML parser/formatter crunches that
>> happily.
>>
> 
> There's a fedora bug about this particular issue:
> 
> https://bugzilla.redhat.com/show_bug.cgi?id=1353296

Ah, thank you for pointing that out. I often forget about those.

> 
> But for example this range still rejects other valid characters as well, like
> unicode á . So maybe rather than a whitelist, we go the opposite way and make
> this a minimal blacklist, or drop the validation entirely. Unless there's some
> designated way to handle regex validation for unicode...

Yeah, I guess we can drop the validation completely. I see couple of
reasons to do that:
a) all modern filesystems allow users to have whatever character they
want in the file name (except NULL) [1]
b) we must not think about disk sources as UNIX style paths. I mean,
there are some hypervisors (like ESX) where disk source is just a name
that is translated by hypervisor then into a path that it understands.
c) it's okay if we have wider schema but narrower parser. I mean, if
schema allows something that is later reject by parser.

Will post v2. Thank you.

Michal

1: https://en.wikipedia.org/wiki/Comparison_of_file_systems#Limits