Re: [Qemu-devel] [RFC v0] HACK: qom: object_property_set: abort on failure

[Anthony Liguori <aliguori@us.ibm.com>]

"Peter A. G. Crosthwaite" <peter.crosthwaite@petalogix.com> writes:

> Hi All. A couple of times now ive had debug issues due to silent failure of
> object_property_set. This function silently fails if the requested property
> does not exist for the target object. To trap this error I applied the patch
> below to my tree, but I am assuming that this is not mergeable as is as im
> guessing there are clients out there that are speculatively trying to set props.
>
> Could someone confirm the expected policy here? is setting a non-existant
> property supposed to be a no-op (as it currently is) or should it fail
> gracefully?

Are you calling set via object_property_set_[str,int,bool,...]?

Why don't you add a terminal error to those functions if setting fails and errp
is NULL.

Regards,

Anthony Liguori

>
> Whats the best meachinism for creating a no_fail version of object_property_set,
> for the 90% case where a non-existant property is an error in machine model
> development?
>
> Signed-off-by: Peter A. G. Crosthwaite <peter.crosthwaite@petalogix.com>
> ---
>  qom/object.c |    2 +-
>  1 files changed, 1 insertions(+), 1 deletions(-)
>
> diff --git a/qom/object.c b/qom/object.c
> index a552be2..6e875a8 100644
> --- a/qom/object.c
> +++ b/qom/object.c
> @@ -687,7 +687,7 @@ void object_property_set(Object *obj, Visitor *v, const char *name,
>  {
>      ObjectProperty *prop = object_property_find(obj, name, errp);
>      if (prop == NULL) {
> -        return;
> +        abort();
>      }
>  
>      if (!prop->set) {
> -- 
> 1.7.0.4