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// SPDX-License-Identifier: LGPL-2.1+
/* NetworkManager -- Network link manager
*
* (C) Copyright 2017 Red Hat, Inc.
*/
#ifndef __NM_OBJ_H__
#define __NM_OBJ_H__
/*****************************************************************************/
#define NM_OBJ_REF_COUNT_STACKINIT (G_MAXINT)
typedef struct _NMObjBaseInst NMObjBaseInst;
typedef struct _NMObjBaseClass NMObjBaseClass;
struct _NMObjBaseInst {
/* The first field of NMObjBaseInst is compatible with GObject.
* Basically, NMObjBaseInst is an abstract base type of GTypeInstance.
*
* If you do it right, you may derive a type of NMObjBaseInst as a proper GTypeInstance.
* That involves allocating a GType for it, which can be inconvenient because
* a GType is dynamically created (and the class can no longer be immutable
* memory).
*
* Even if your implementation of NMObjBaseInst is not a full fledged GType(Instance),
* you still can use GTypeInstances in the same context as you can decide based on the
* NMObjBaseClass with what kind of object you are dealing with.
*
* Basically, the only thing NMObjBaseInst gives you is access to an
* NMObjBaseClass instance.
*/
union {
const NMObjBaseClass *klass;
GTypeInstance g_type_instance;
};
};
struct _NMObjBaseClass {
/* NMObjBaseClass is the base class of all NMObjBaseInst implementations.
* Note that it is also an abstract super class of GTypeInstance, that means
* you may implement a NMObjBaseClass as a subtype of GTypeClass.
*
* For that to work, you must properly set the GTypeClass instance (and its
* GType).
*
* Note that to implement a NMObjBaseClass that is *not* a GTypeClass, you wouldn't
* set the GType. Hence, this field is only useful for type implementations that actually
* extend GTypeClass.
*
* In a way it is wrong that NMObjBaseClass has the GType member, because it is
* a base class of GTypeClass and doesn't necessarily use the GType. However,
* it is here so that G_TYPE_CHECK_INSTANCE_TYPE() and friends work correctly
* on any NMObjectClass. That means, while not necessary, it is convenient that
* a NMObjBaseClass has all members of GTypeClass.
* Also note that usually you have only one instance of a certain type, so this
* wastes just a few bytes for the unneeded GType.
*/
union {
GType g_type;
GTypeClass g_type_class;
};
};
/*****************************************************************************/
#endif /* __NM_OBJ_H__ */
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