Re: [PATCH v2 2/3] qom: move user_creatable_add_opts logic to vl.c and QAPIfy it

[Paolo Bonzini]

On 13/04/21 11:48, Markus Armbruster wrote:
> > Oh, there is qapi/qom.json -- maybe that does the trick.
> >
> > (I have mixed feelings about having to specify the same thing twice at
> > different locations)
>
> With reason.
>
> We've talked about generating QOM boilerplate from the QAPI schema, but
> haven't progressed to actual patches.

There is an initial sketch at
https://wiki.qemu.org/Features/QOM-QAPI_integration, covering what can 
be done before touching the code generator.

The basic idea is to keep property getters, which allow to read how an 
object was configured and already vastly reduces the amount of 
boilerplate, and replace the setters with a method that takes a QAPI 
visitor.

Later on the low-level QAPI code can be generated by qapi-gen, similar 
to QMP commands.  However, unlike QMP (where QAPIfication included 
switching from raw QDicts to QAPI structs) here we already start with 
code that uses vistors and QAPI structs.  So it's not like having to 
rewrite things twice.

Paolo