[PATCH v2] ui: Make the DisplayType enum entries conditional

[Gerd Hoffmann]

On Tue, Jun 15, 2021 at 11:04:39AM +0200, Thomas Huth wrote:
> Libvirt's "domcapabilities" command has a way to state whether certain
> graphic frontends are available in QEMU or not. Originally, libvirt
> looked at the "--help" output of the QEMU binary to determine whether
> SDL was available or not (by looking for the "-sdl" parameter in the
> help text), but since libvirt stopped doing this analysis of the help
> text, the detection of SDL is currently broken, see:
> 
>  https://bugzilla.redhat.com/show_bug.cgi?id=1790902
> 
> QEMU should provide a way via the QMP interface instead. A simple way,
> without introducing additional commands, is to make the DisplayType
> enum entries conditional, so that the enum only contains the entries if
> the corresponding CONFIG_xxx switches have been set. This of course
> only gives an indication which possibilities have been enabled during
> compile-time of QEMU (and does not take into account whether modules
> are later available or not for example - for this we'd need a separate
> command), but anyway, this should already be good enough for the above
> bug ticket, and it's a good idea anyway to make the QMP interface
> conditional here, so let's simply do it.
> 
> Signed-off-by: Thomas Huth <thuth at redhat.com>

Added to ui queue.

thanks,
  Gerd