Mercurial > repos > rliterman > csp2

comparison CSP2/CSP2_env/env-d9b9114564458d9d-741b3de822f2aaca6c6caa4325c4afce/include/python3.8/weakrefobject.h @ 69:33d812a61356

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
planemo upload commit 2e9511a184a1ca667c7be0c6321a36dc4e3d116d
author jpayne
date Tue, 18 Mar 2025 17:55:14 -0400
parents
children
comparison
equal deleted inserted replaced
67:0e9998148a16 69:33d812a61356
1 /* Weak references objects for Python. */
2
3 #ifndef Py_WEAKREFOBJECT_H
4 #define Py_WEAKREFOBJECT_H
5 #ifdef __cplusplus
6 extern "C" {
7 #endif
8
9
10 typedef struct _PyWeakReference PyWeakReference;
11
12 /* PyWeakReference is the base struct for the Python ReferenceType, ProxyType,
13 * and CallableProxyType.
14 */
15 #ifndef Py_LIMITED_API
16 struct _PyWeakReference {
17 PyObject_HEAD
18
19 /* The object to which this is a weak reference, or Py_None if none.
20 * Note that this is a stealth reference: wr_object's refcount is
21 * not incremented to reflect this pointer.
22 */
23 PyObject *wr_object;
24
25 /* A callable to invoke when wr_object dies, or NULL if none. */
26 PyObject *wr_callback;
27
28 /* A cache for wr_object's hash code. As usual for hashes, this is -1
29 * if the hash code isn't known yet.
30 */
31 Py_hash_t hash;
32
33 /* If wr_object is weakly referenced, wr_object has a doubly-linked NULL-
34 * terminated list of weak references to it. These are the list pointers.
35 * If wr_object goes away, wr_object is set to Py_None, and these pointers
36 * have no meaning then.
37 */
38 PyWeakReference *wr_prev;
39 PyWeakReference *wr_next;
40 };
41 #endif
42
43 PyAPI_DATA(PyTypeObject) _PyWeakref_RefType;
44 PyAPI_DATA(PyTypeObject) _PyWeakref_ProxyType;
45 PyAPI_DATA(PyTypeObject) _PyWeakref_CallableProxyType;
46
47 #define PyWeakref_CheckRef(op) PyObject_TypeCheck(op, &_PyWeakref_RefType)
48 #define PyWeakref_CheckRefExact(op) \
49 (Py_TYPE(op) == &_PyWeakref_RefType)
50 #define PyWeakref_CheckProxy(op) \
51 ((Py_TYPE(op) == &_PyWeakref_ProxyType) || \
52 (Py_TYPE(op) == &_PyWeakref_CallableProxyType))
53
54 #define PyWeakref_Check(op) \
55 (PyWeakref_CheckRef(op) || PyWeakref_CheckProxy(op))
56
57
58 PyAPI_FUNC(PyObject *) PyWeakref_NewRef(PyObject *ob,
59 PyObject *callback);
60 PyAPI_FUNC(PyObject *) PyWeakref_NewProxy(PyObject *ob,
61 PyObject *callback);
62 PyAPI_FUNC(PyObject *) PyWeakref_GetObject(PyObject *ref);
63
64 #ifndef Py_LIMITED_API
65 PyAPI_FUNC(Py_ssize_t) _PyWeakref_GetWeakrefCount(PyWeakReference *head);
66
67 PyAPI_FUNC(void) _PyWeakref_ClearRef(PyWeakReference *self);
68 #endif
69
70 /* Explanation for the Py_REFCNT() check: when a weakref's target is part
71 of a long chain of deallocations which triggers the trashcan mechanism,
72 clearing the weakrefs can be delayed long after the target's refcount
73 has dropped to zero. In the meantime, code accessing the weakref will
74 be able to "see" the target object even though it is supposed to be
75 unreachable. See issue #16602. */
76
77 #define PyWeakref_GET_OBJECT(ref) \
78 (Py_REFCNT(((PyWeakReference *)(ref))->wr_object) > 0 \
79 ? ((PyWeakReference *)(ref))->wr_object \
80 : Py_None)
81
82
83 #ifdef __cplusplus
84 }
85 #endif
86 #endif /* !Py_WEAKREFOBJECT_H */