mirror of https://github.com/python/cpython
76 lines
2.4 KiB
C
76 lines
2.4 KiB
C
/* Weak references objects for Python. */
|
|
|
|
#ifndef Py_WEAKREFOBJECT_H
|
|
#define Py_WEAKREFOBJECT_H
|
|
#ifdef __cplusplus
|
|
extern "C" {
|
|
#endif
|
|
|
|
|
|
typedef struct _PyWeakReference PyWeakReference;
|
|
|
|
/* PyWeakReference is the base struct for the Python ReferenceType, ProxyType,
|
|
* and CallableProxyType.
|
|
*/
|
|
struct _PyWeakReference {
|
|
PyObject_HEAD
|
|
|
|
/* The object to which this is a weak reference, or Py_None if none.
|
|
* Note that this is a stealth reference: wr_object's refcount is
|
|
* not incremented to reflect this pointer.
|
|
*/
|
|
PyObject *wr_object;
|
|
|
|
/* A callable to invoke when wr_object dies, or NULL if none. */
|
|
PyObject *wr_callback;
|
|
|
|
/* A cache for wr_object's hash code. As usual for hashes, this is -1
|
|
* if the hash code isn't known yet.
|
|
*/
|
|
long hash;
|
|
|
|
/* If wr_object is weakly referenced, wr_object has a doubly-linked NULL-
|
|
* terminated list of weak references to it. These are the list pointers.
|
|
* If wr_object goes away, wr_object is set to Py_None, and these pointers
|
|
* have no meaning then.
|
|
*/
|
|
PyWeakReference *wr_prev;
|
|
PyWeakReference *wr_next;
|
|
};
|
|
|
|
PyAPI_DATA(PyTypeObject) _PyWeakref_RefType;
|
|
PyAPI_DATA(PyTypeObject) _PyWeakref_ProxyType;
|
|
PyAPI_DATA(PyTypeObject) _PyWeakref_CallableProxyType;
|
|
|
|
#define PyWeakref_CheckRef(op) PyObject_TypeCheck(op, &_PyWeakref_RefType)
|
|
#define PyWeakref_CheckRefExact(op) \
|
|
(Py_TYPE(op) == &_PyWeakref_RefType)
|
|
#define PyWeakref_CheckProxy(op) \
|
|
((Py_TYPE(op) == &_PyWeakref_ProxyType) || \
|
|
(Py_TYPE(op) == &_PyWeakref_CallableProxyType))
|
|
|
|
/* This macro calls PyWeakref_CheckRef() last since that can involve a
|
|
function call; this makes it more likely that the function call
|
|
will be avoided. */
|
|
#define PyWeakref_Check(op) \
|
|
(PyWeakref_CheckRef(op) || PyWeakref_CheckProxy(op))
|
|
|
|
|
|
PyAPI_FUNC(PyObject *) PyWeakref_NewRef(PyObject *ob,
|
|
PyObject *callback);
|
|
PyAPI_FUNC(PyObject *) PyWeakref_NewProxy(PyObject *ob,
|
|
PyObject *callback);
|
|
PyAPI_FUNC(PyObject *) PyWeakref_GetObject(PyObject *ref);
|
|
|
|
PyAPI_FUNC(Py_ssize_t) _PyWeakref_GetWeakrefCount(PyWeakReference *head);
|
|
|
|
PyAPI_FUNC(void) _PyWeakref_ClearRef(PyWeakReference *self);
|
|
|
|
#define PyWeakref_GET_OBJECT(ref) (((PyWeakReference *)(ref))->wr_object)
|
|
|
|
|
|
#ifdef __cplusplus
|
|
}
|
|
#endif
|
|
#endif /* !Py_WEAKREFOBJECT_H */
|