Re: [Qemu-devel] [PATCH 1/9] qom: add qom_init_completion

[Paolo Bonzini <pbonzini@redhat.com>]

Il 03/05/2013 18:03, Michael Roth ha scritto:
> This is similar in concept to "realize", though semantics are a
> bit more open-ended:
> 
> And object might in some cases need a number of properties to be
> specified before it can be "used"/"started"/etc. This can't always
> be done via an open-ended new() function, the main example being objects
> that around created via the command-line by -object.
> 
> To support these cases we allow a function, ->instance_init_completion,
> to be registered that will be called by the -object constructor, or can
> be called at the end of new() constructors and such.

This seems a lot like a realize property that cannot be set back to false...

Paolo

> Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
> ---
>  include/qom/object.h |   19 +++++++++++++++++++
>  qom/object.c         |   21 +++++++++++++++++++++
>  vl.c                 |    2 ++
>  3 files changed, 42 insertions(+)
> 
> diff --git a/include/qom/object.h b/include/qom/object.h
> index d0f99c5..86f1e2e 100644
> --- a/include/qom/object.h
> +++ b/include/qom/object.h
> @@ -394,6 +394,11 @@ struct Object
>   * @instance_init: This function is called to initialize an object.  The parent
>   *   class will have already been initialized so the type is only responsible
>   *   for initializing its own members.
> + * @instance_init_completion: This function is used mainly cases where an
> + *   object has been instantiated via the command-line, and is called once all
> + *   properties specified via command-line have been set for the object. This
> + *   is not called automatically, but manually via @object_init_completion once
> + *   the processing of said properties is completed.
>   * @instance_finalize: This function is called during object destruction.  This
>   *   is called before the parent @instance_finalize function has been called.
>   *   An object should only free the members that are unique to its type in this
> @@ -429,6 +434,7 @@ struct TypeInfo
>  
>      size_t instance_size;
>      void (*instance_init)(Object *obj);
> +    void (*instance_init_completion)(Object *obj);
>      void (*instance_finalize)(Object *obj);
>  
>      bool abstract;
> @@ -562,6 +568,19 @@ struct InterfaceClass
>  Object *object_new(const char *typename);
>  
>  /**
> + * object_init_completion:
> + * @obj: The object to complete initialization of
> + *
> + * In cases where an object is instantiated from a command-line with a number
> + * of properties specified as parameters (generally via -object), or for cases
> + * where a new()/helper function is used to pass/set some minimal number of
> + * properties that are required prior to completion of object initialization,
> + * this function can be called to mark when that occurs to complete object
> + * initialization.
> + */
> +void object_init_completion(Object *obj);
> +
> +/**
>   * object_new_with_type:
>   * @type: The type of the object to instantiate.
>   *
> diff --git a/qom/object.c b/qom/object.c
> index 75e6aac..c932f64 100644
> --- a/qom/object.c
> +++ b/qom/object.c
> @@ -50,6 +50,7 @@ struct TypeImpl
>      void *class_data;
>  
>      void (*instance_init)(Object *obj);
> +    void (*instance_init_completion)(Object *obj);
>      void (*instance_finalize)(Object *obj);
>  
>      bool abstract;
> @@ -110,6 +111,7 @@ static TypeImpl *type_register_internal(const TypeInfo *info)
>      ti->class_data = info->class_data;
>  
>      ti->instance_init = info->instance_init;
> +    ti->instance_init_completion = info->instance_init_completion;
>      ti->instance_finalize = info->instance_finalize;
>  
>      ti->abstract = info->abstract;
> @@ -422,6 +424,25 @@ Object *object_new(const char *typename)
>      return object_new_with_type(ti);
>  }
>  
> +
> +static void object_init_completion_with_type(Object *obj, TypeImpl *ti)
> +{
> +    if (type_has_parent(ti)) {
> +        object_init_completion_with_type(obj, type_get_parent(ti));
> +    }
> +
> +    if (ti->instance_init_completion) {
> +        ti->instance_init_completion(obj);
> +    }
> +}
> +
> +void object_init_completion(Object *obj)
> +{
> +    TypeImpl *ti = type_get_by_name(object_get_class(obj)->type->name);
> +
> +    object_init_completion_with_type(obj, ti);
> +}
> +
>  Object *object_dynamic_cast(Object *obj, const char *typename)
>  {
>      if (obj && object_class_dynamic_cast(object_get_class(obj), typename)) {
> diff --git a/vl.c b/vl.c
> index 6e6225f..d454c86 100644
> --- a/vl.c
> +++ b/vl.c
> @@ -2831,6 +2831,8 @@ static int object_create(QemuOpts *opts, void *opaque)
>      object_property_add_child(container_get(object_get_root(), "/objects"),
>                                id, obj, NULL);
>  
> +    object_init_completion(obj);
> +
>      return 0;
>  }
>  
>