Re: [Qemu-devel] [PATCH v5] qom, qmp, hmp, qapi: create qom-type-prop-list for class properties

[Eduardo Habkost <ehabkost@redhat.com>]

On Mon, Jan 25, 2016 at 11:24:47AM +0300, Valentin Rakush wrote:
> This patch adds support for qom-type-prop-list command to list object
> class properties. A later patch will use this functionality to
> implement x86_64-cpu properties.
> 
> Signed-off-by: Valentin Rakush <valentin.rakush@gmail.com>
> Cc: Luiz Capitulino <lcapitulino@redhat.com>
> Cc: Eric Blake <eblake@redhat.com>
> Cc: Markus Armbruster <armbru@redhat.com>
> Cc: Andreas Färber <afaerber@suse.de>
> Cc: Daniel P. Berrange <berrange@redhat.com>
> Cc: Eduardo Habkost <ehabkost@redhat.com>
> ---
[...]
> diff --git a/qmp.c b/qmp.c
> index 53affe2..baf25c0 100644
> --- a/qmp.c
> +++ b/qmp.c
> @@ -460,6 +460,37 @@ ObjectTypeInfoList *qmp_qom_list_types(bool has_implements,
>      return ret;
>  }
>  
> +ObjectPropertyInfoList *qmp_qom_type_prop_list(const char *typename, Error **errp)
> +{
> +    ObjectClass *klass;
> +    ObjectPropertyInfoList *props = NULL;
> +    ObjectProperty *prop;
> +    ObjectPropertyIterator iter;
> +
> +    klass = object_class_by_name(typename);
> +    if (!klass) {
> +        error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
> +                  "Object class '%s' not found", typename);
> +        return NULL;
> +    }
> +
> +    object_class_property_iter_init(&iter, klass);
> +    while ((prop = object_property_iter_next(&iter))) {
> +        ObjectPropertyInfoList *entry = g_new0(ObjectPropertyInfoList, 1);
> +
> +        if (entry) {
> +            entry->value = g_new0(ObjectPropertyInfo, 1);
> +            entry->next = props;
> +            props = entry;
> +
> +            entry->value->name = g_strdup(prop->name);
> +            entry->value->type = g_strdup(prop->type);
> +        }
> +    }
> +
> +    return props;
> +}
> +

We already have "-device <type>,help", and it uses a completely
different mechanism for listing properties. There's no reason for
having two arbitrarily different APIs for listing properties
returning different results.

If qmp_device_list_properties() is not enough for you, please
clarify why, so we can consider improving it.


>  /* Return a DevicePropertyInfo for a qdev property.
>   *
>   * If a qdev property with the given name does not exist, use the given default
> diff --git a/qom/object.c b/qom/object.c
> index 5ff97ab..cabd91d 100644
> --- a/qom/object.c
> +++ b/qom/object.c
> @@ -994,6 +994,13 @@ ObjectProperty *object_property_find(Object *obj, const char *name,
>      return NULL;
>  }
>  
> +void object_class_property_iter_init(ObjectPropertyIterator *iter,
> +                                     ObjectClass *klass)
> +{
> +    g_hash_table_iter_init(&iter->iter, klass->properties);
> +    iter->nextclass = object_class_get_parent(klass);
> +}
> +
>  void object_property_iter_init(ObjectPropertyIterator *iter,
>                                 Object *obj)
>  {
> -- 
> 1.8.3.1
> 

-- 
Eduardo