qemu/include/qom/object_interfaces.h
Igor Mammedov 269e09f3fc add optional 2nd stage initialization to -object/object-add commands
Introduces USER_CREATABLE interface that must be implemented by
objects which are designed to created with -object CLI option or
object-add QMP command.

Interface provides an ability to do an optional second stage
initialization of the object created with -object/object-add
commands. By providing complete() callback, which is called
after the object properties were set.

It allows to:
 * prevents misusing of -object/object-add by filtering out
   objects that are not designed for it.
 * generalize second stage backend initialization instead of
   adding custom APIs to perform it
 * early error detection of backend initialization at -object/
   object-add time rather than through a proxy DEVICE object
   that tries to use backend.

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2014-01-28 12:47:02 -05:00

63 lines
1.9 KiB
C

#ifndef OBJECT_INTERFACES_H
#define OBJECT_INTERFACES_H
#include "qom/object.h"
#define TYPE_USER_CREATABLE "user-creatable"
#define USER_CREATABLE_CLASS(klass) \
OBJECT_CLASS_CHECK(UserCreatableClass, (klass), \
TYPE_USER_CREATABLE)
#define USER_CREATABLE_GET_CLASS(obj) \
OBJECT_GET_CLASS(UserCreatableClass, (obj), \
TYPE_USER_CREATABLE)
#define USER_CREATABLE(obj) \
INTERFACE_CHECK(UserCreatable, (obj), \
TYPE_USER_CREATABLE)
typedef struct UserCreatable {
/* <private> */
Object Parent;
} UserCreatable;
/**
* UserCreatableClass:
* @parent_class: the base class
* @complete: callback to be called after @obj's properties are set.
*
* Interface is designed to work with -object/object-add/object_add
* commands.
* Interface is mandatory for objects that are designed to be user
* creatable (i.e. -object/object-add/object_add, will accept only
* objects that inherit this interface).
*
* Interface also provides an optional ability to do the second
* stage * initialization of the object after its properties were
* set.
*
* For objects created without using -object/object-add/object_add,
* @user_creatable_complete() wrapper should be called manually if
* object's type implements USER_CREATABLE interface and needs
* complete() callback to be called.
*/
typedef struct UserCreatableClass {
/* <private> */
InterfaceClass parent_class;
/* <public> */
void (*complete)(UserCreatable *uc, Error **errp);
} UserCreatableClass;
/**
* user_creatable_complete:
* @obj: the object whose complete() method is called if defined
* @errp: if an error occurs, a pointer to an area to store the error
*
* Wrapper to call complete() method if one of types it's inherited
* from implements USER_CREATABLE interface, otherwise the call does
* nothing.
*/
void user_creatable_complete(Object *obj, Error **errp);
#endif