1/* Set object interface */
2
3#ifndef Py_SETOBJECT_H
4#define Py_SETOBJECT_H
5#ifdef __cplusplus
6extern "C" {
7#endif
8
9
10/*
11There are three kinds of slots in the table:
12
131. Unused:  key == NULL
142. Active:  key != NULL and key != dummy
153. Dummy:   key == dummy
16
17Note: .pop() abuses the hash field of an Unused or Dummy slot to
18hold a search finger.  The hash field of Unused or Dummy slots has
19no meaning otherwise.
20*/
21
22#define PySet_MINSIZE 8
23
24typedef struct {
25    long hash;      /* cached hash code for the entry key */
26    PyObject *key;
27} setentry;
28
29
30/*
31This data structure is shared by set and frozenset objects.
32*/
33
34typedef struct _setobject PySetObject;
35struct _setobject {
36    PyObject_HEAD
37
38    Py_ssize_t fill;  /* # Active + # Dummy */
39    Py_ssize_t used;  /* # Active */
40
41    /* The table contains mask + 1 slots, and that's a power of 2.
42     * We store the mask instead of the size because the mask is more
43     * frequently needed.
44     */
45    Py_ssize_t mask;
46
47    /* table points to smalltable for small tables, else to
48     * additional malloc'ed memory.  table is never NULL!  This rule
49     * saves repeated runtime null-tests.
50     */
51    setentry *table;
52    setentry *(*lookup)(PySetObject *so, PyObject *key, long hash);
53    setentry smalltable[PySet_MINSIZE];
54
55    long hash;                  /* only used by frozenset objects */
56    PyObject *weakreflist;      /* List of weak references */
57};
58
59PyAPI_DATA(PyTypeObject) PySet_Type;
60PyAPI_DATA(PyTypeObject) PyFrozenSet_Type;
61
62/* Invariants for frozensets:
63 *     data is immutable.
64 *     hash is the hash of the frozenset or -1 if not computed yet.
65 * Invariants for sets:
66 *     hash is -1
67 */
68
69#define PyFrozenSet_CheckExact(ob) (Py_TYPE(ob) == &PyFrozenSet_Type)
70#define PyAnySet_CheckExact(ob) \
71    (Py_TYPE(ob) == &PySet_Type || Py_TYPE(ob) == &PyFrozenSet_Type)
72#define PyAnySet_Check(ob) \
73    (Py_TYPE(ob) == &PySet_Type || Py_TYPE(ob) == &PyFrozenSet_Type || \
74      PyType_IsSubtype(Py_TYPE(ob), &PySet_Type) || \
75      PyType_IsSubtype(Py_TYPE(ob), &PyFrozenSet_Type))
76#define PySet_Check(ob) \
77    (Py_TYPE(ob) == &PySet_Type || \
78    PyType_IsSubtype(Py_TYPE(ob), &PySet_Type))
79#define   PyFrozenSet_Check(ob) \
80    (Py_TYPE(ob) == &PyFrozenSet_Type || \
81      PyType_IsSubtype(Py_TYPE(ob), &PyFrozenSet_Type))
82
83PyAPI_FUNC(PyObject *) PySet_New(PyObject *);
84PyAPI_FUNC(PyObject *) PyFrozenSet_New(PyObject *);
85PyAPI_FUNC(Py_ssize_t) PySet_Size(PyObject *anyset);
86#define PySet_GET_SIZE(so) (((PySetObject *)(so))->used)
87PyAPI_FUNC(int) PySet_Clear(PyObject *set);
88PyAPI_FUNC(int) PySet_Contains(PyObject *anyset, PyObject *key);
89PyAPI_FUNC(int) PySet_Discard(PyObject *set, PyObject *key);
90PyAPI_FUNC(int) PySet_Add(PyObject *set, PyObject *key);
91PyAPI_FUNC(int) _PySet_Next(PyObject *set, Py_ssize_t *pos, PyObject **key);
92PyAPI_FUNC(int) _PySet_NextEntry(PyObject *set, Py_ssize_t *pos, PyObject **key, long *hash);
93PyAPI_FUNC(PyObject *) PySet_Pop(PyObject *set);
94PyAPI_FUNC(int) _PySet_Update(PyObject *set, PyObject *iterable);
95
96#ifdef __cplusplus
97}
98#endif
99#endif /* !Py_SETOBJECT_H */
100