Re: [PATCH v3 00/30] qapi/qom: QAPIfy --object and object-add

[Markus Armbruster]

Paolo Bonzini <pbonzini@redhat.com> writes:

> On 11/03/21 11:38, Markus Armbruster wrote:
>> Here's a differently terrible hack.  We have
>>           keyval_parse()       visitor
>>      optarg --------> QObject --------> QAPI type
>> Idea: hack the QObject.  If we're working for -object, and QObject
>> maps
>> key "qom-type" to value "memory-backend-ram", get the value of
>> host-nodes, and if it's a string, parse it into a list like the opts
>> visitor does, and put that back, replacing the string value.
>> Same for other uses of Memdev and NumaNodeOptions with -object, if
>> they
>> exist.
>
> This doesn't help with backwards compatibility, since keyval loses the
> first of host-nodes=0,host-nodes=4.

You're right, I missed the fact that we rely on both hacks working
together for the full syntax.

> I would rather keep the OptsVisitor here.  Do the same check for JSON
> syntax that you have in qobject_input_visitor_new_str, and whenever
> you need to walk all -object arguments, use something like this:
>
>     typedef struct ObjectArgument {
>         const char *id;
>         QDict *json;    /* or NULL for QemuOpts */
>         QSIMPLEQ_ENTRY(ObjectArgument) next;
>     }
>
> I already had patches in my queue to store -object in a GSList of
> dictionaries, changing it to use the above is easy enough.

I think I'd prefer following -display's precedence.  See my reply to
Kevin for details.