Re: [Qemu-devel] [PATCH 12/13] qapi: support for keyworded variable-length argument list

[Luiz Capitulino <lcapitulino@redhat.com>]

On Thu, 29 Mar 2012 13:26:34 -0500
Anthony Liguori <aliguori@us.ibm.com> wrote:

> On 03/29/2012 12:26 PM, Luiz Capitulino wrote:
> > This allows for QAPI functions to receive a variable-length argument
> > list. This is going to be used by device_add and netdev_add commands.
> >
> > In the schema, the argument list is represented by type name '**',
> > like this example:
> >
> >      { 'command': 'foo', 'data': { 'arg-list': '**' } }
> >
> > Each argument is represented by the KeyValues type and the C
> > implementation should expect a KeyValuesList, like:
> >
> >      void qmp_foo(KeyValuesList *values_list, Error **errp);
> >
> > XXX: This implementation is simple but very hacky. We just iterate
> >       through all arguments and build the KeyValuesList list to be
> >       passed to the QAPI function.
> >
> >       Maybe we could have a kwargs type, that does exactly this but
> >       through a visitor instead?
> >
> > Signed-off-by: Luiz Capitulino<lcapitulino@redhat.com>
> 
> What about just treating '**' as "marshal remaining arguments to a string" and 
> then pass that string to device_add?  qmp_device_add can then parse that string 
> with QemuOpts.

If this turns out to be simple enough, I'm fine with it.

> It's a bit ugly, but that's how things worked.  When we introduce qom_add, this 
> problem goes away because you would make multiple calls to qom_set to set all of 
> the properties.

Just out of curiosity, is qom_add going to supersede device_add?