qemu-e2k/include/qom/object_interfaces.h
Daniel P. Berrange 90998d5896 qom: add helpers for UserCreatable object types
The QMP monitor code has two helper methods object_add
and qmp_object_del that are called from several places
in the code (QMP, HMP and main emulator startup).

The HMP and main emulator startup code also share
further logic that extracts the qom-type & id
values from a qdict.

We soon need to use this logic from qemu-img, qemu-io
and qemu-nbd too, but don't want those to depend on
the monitor, nor do we want to duplicate the code.

To avoid this, move some code out of qmp.c and hmp.c
adding new methods to qom/object_interfaces.c

 - user_creatable_add - takes a QDict holding a full
   object definition & instantiates it
 - user_creatable_add_type - takes an ID, type name,
   and QDict holding object properties & instantiates
   it
 - user_creatable_add_opts - takes a QemuOpts holding
   a full object definition & instantiates it
 - user_creatable_add_opts_foreach - variant on
   user_creatable_add_opts which can be directly used
   in conjunction with qemu_opts_foreach.
 - user_creatable_del - takes an ID and deletes the
   corresponding object

The existing code is updated to use these new methods.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1455129674-17255-2-git-send-email-berrange@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-02-16 17:12:57 +01:00

168 lines
5.5 KiB
C

#ifndef OBJECT_INTERFACES_H
#define OBJECT_INTERFACES_H
#include "qom/object.h"
#include "qapi/qmp/qdict.h"
#include "qapi/visitor.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.
* @can_be_deleted: callback to be called before an object is removed
* to check if @obj can be removed safely.
*
* 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);
bool (*can_be_deleted)(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);
/**
* user_creatable_can_be_deleted:
* @uc: the object whose can_be_deleted() method is called if implemented
* @errp: if an error occurs, a pointer to an area to store the error
*
* Wrapper to call can_be_deleted() method if one of types it's inherited
* from implements USER_CREATABLE interface.
*/
bool user_creatable_can_be_deleted(UserCreatable *uc, Error **errp);
/**
* user_creatable_add:
* @qdict: the object definition
* @v: the visitor
* @errp: if an error occurs, a pointer to an area to store the error
*
* Create an instance of the user creatable object whose type
* is defined in @qdict by the 'qom-type' field, placing it
* in the object composition tree with name provided by the
* 'id' field. The remaining fields in @qdict are used to
* initialize the object properties.
*
* Returns: the newly created object or NULL on error
*/
Object *user_creatable_add(const QDict *qdict,
Visitor *v, Error **errp);
/**
* user_creatable_add_type:
* @type: the object type name
* @id: the unique ID for the object
* @qdict: the object properties
* @v: the visitor
* @errp: if an error occurs, a pointer to an area to store the error
*
* Create an instance of the user creatable object @type, placing
* it in the object composition tree with name @id, initializing
* it with properties from @qdict
*
* Returns: the newly created object or NULL on error
*/
Object *user_creatable_add_type(const char *type, const char *id,
const QDict *qdict,
Visitor *v, Error **errp);
/**
* user_creatable_add_opts:
* @opts: the object definition
* @errp: if an error occurs, a pointer to an area to store the error
*
* Create an instance of the user creatable object whose type
* is defined in @opts by the 'qom-type' option, placing it
* in the object composition tree with name provided by the
* 'id' field. The remaining options in @opts are used to
* initialize the object properties.
*
* Returns: the newly created object or NULL on error
*/
Object *user_creatable_add_opts(QemuOpts *opts, Error **errp);
/**
* user_creatable_add_opts_predicate:
* @type: the QOM type to be added
*
* A callback function to determine whether an object
* of type @type should be created. Instances of this
* callback should be passed to user_creatable_add_opts_foreach
*/
typedef bool (*user_creatable_add_opts_predicate)(const char *type);
/**
* user_creatable_add_opts_foreach:
* @opaque: a user_creatable_add_opts_predicate callback or NULL
* @opts: options to create
* @errp: if an error occurs, a pointer to an area to store the error
*
* An iterator callback to be used in conjunction with
* the qemu_opts_foreach() method for creating a list of
* objects from a set of QemuOpts
*
* The @opaque parameter can be passed a user_creatable_add_opts_predicate
* callback to filter which types of object are created during iteration.
*
* Returns: 0 on success, -1 on error
*/
int user_creatable_add_opts_foreach(void *opaque,
QemuOpts *opts, Error **errp);
/**
* user_creatable_del:
* @id: the unique ID for the object
* @errp: if an error occurs, a pointer to an area to store the error
*
* Delete an instance of the user creatable object identified
* by @id.
*/
void user_creatable_del(const char *id, Error **errp);
#endif