Re: [Qemu-devel] [PATCH 4/5] Use libuuid if available.

[Daniel P. Berrange]

On Thu, Jun 05, 2008 at 11:22:17PM +0100, Paul Brook wrote:
> On Thursday 05 June 2008, Anthony Liguori wrote:
> > Gleb Natapov wrote:
> > > Anthony, thanks for the review.
> > >
> > > On Thu, Jun 05, 2008 at 10:18:15AM -0500, Anthony Liguori wrote:
> > >>> @@ -256,8 +260,14 @@ static void do_info_name(void)
> > >>>   static void do_info_uuid(void)
> > >>>  {
> > >>> +#ifdef CONFIG_UUID
> > >>> +    char uuid_str[37];
> > >>> +    uuid_unparse(qemu_uuid, uuid_str);
> > >>> +    term_printf("%s\n", uuid_str);
> > >>> +#else
> > >>
> > >> Just use a printf() string here again to eliminate the need for
> > >> CONFIG_UUID.
> > >
> > > So may be do not use libuuid at all and just write simple uuid string
> > > parsing function?
> >
> > For parsing, sure. But uuid generation requires implementing an
> > algorithm from an RFC. I think that warrants using libuuid.
> 
> Can we punt this to management tools? Having qemu create randomly different 
> machines seems like it's going to cause as many problems as it solves.  We've 
> already got things like MAC addresses which are fixed but need to be unique.

FYI, once you have the -uuid argument supported in QEMU, I'll update libvirt
to use it, and libvirt will always generate a random UUID when invoking QEMU
if the user didn't specify one explicitly. So for any management tool using
libvirt, there's no need for QEMU itself to generate random UUIDs.

Regards,
Daniel.
-- 
|: Red Hat, Engineering, London   -o-   http://people.redhat.com/berrange/ :|
|: http://libvirt.org  -o-  http://virt-manager.org  -o-  http://ovirt.org :|
|: http://autobuild.org       -o-         http://search.cpan.org/~danberr/ :|
|: GnuPG: 7D3B9505  -o-  F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 :|