111 lines
4.1 KiB
C
111 lines
4.1 KiB
C
#ifndef Py_DICTOBJECT_H
|
|
#define Py_DICTOBJECT_H
|
|
#ifdef __cplusplus
|
|
extern "C" {
|
|
#endif
|
|
|
|
|
|
/* Dictionary object type -- mapping from hashable object to object */
|
|
|
|
/*
|
|
There are three kinds of slots in the table:
|
|
|
|
1. Unused. me_key == me_value == NULL
|
|
Does not hold an active (key, value) pair now and never did. Unused can
|
|
transition to Active upon key insertion. This is the only case in which
|
|
me_key is NULL, and is each slot's initial state.
|
|
|
|
2. Active. me_key != NULL and me_key != dummy and me_value != NULL
|
|
Holds an active (key, value) pair. Active can transition to Dummy upon
|
|
key deletion. This is the only case in which me_value != NULL.
|
|
|
|
3. Dummy. me_key == dummy and me_value == NULL
|
|
Previously held an active (key, value) pair, but that was deleted and an
|
|
active pair has not yet overwritten the slot. Dummy can transition to
|
|
Active upon key insertion. Dummy slots cannot be made Unused again
|
|
(cannot have me_key set to NULL), else the probe sequence in case of
|
|
collision would have no way to know they were once active.
|
|
|
|
Note: .popitem() abuses the me_hash field of an Unused or Dummy slot to
|
|
hold a search finger. The me_hash field of Unused or Dummy slots has no
|
|
meaning otherwise.
|
|
*/
|
|
|
|
/* PyDict_MINSIZE is the minimum size of a dictionary. This many slots are
|
|
* allocated directly in the dict object (in the ma_smalltable member).
|
|
* It must be a power of 2, and at least 4. 8 allows dicts with no more
|
|
* than 5 active entries to live in ma_smalltable (and so avoid an
|
|
* additional malloc); instrumentation suggested this suffices for the
|
|
* majority of dicts (consisting mostly of usually-small instance dicts and
|
|
* usually-small dicts created to pass keyword arguments).
|
|
*/
|
|
#define PyDict_MINSIZE 8
|
|
|
|
typedef struct {
|
|
long me_hash; /* cached hash code of me_key */
|
|
PyObject *me_key;
|
|
PyObject *me_value;
|
|
#ifdef USE_CACHE_ALIGNED
|
|
long aligner;
|
|
#endif
|
|
} PyDictEntry;
|
|
|
|
/*
|
|
To ensure the lookup algorithm terminates, there must be at least one Unused
|
|
slot (NULL key) in the table.
|
|
The value ma_fill is the number of non-NULL keys (sum of Active and Dummy);
|
|
ma_used is the number of non-NULL, non-dummy keys (== the number of non-NULL
|
|
values == the number of Active items).
|
|
To avoid slowing down lookups on a near-full table, we resize the table when
|
|
it's two-thirds full.
|
|
*/
|
|
typedef struct _dictobject PyDictObject;
|
|
struct _dictobject {
|
|
PyObject_HEAD
|
|
int ma_fill; /* # Active + # Dummy */
|
|
int ma_used; /* # Active */
|
|
|
|
/* The table contains ma_mask + 1 slots, and that's a power of 2.
|
|
* We store the mask instead of the size because the mask is more
|
|
* frequently needed.
|
|
*/
|
|
int ma_mask;
|
|
|
|
/* ma_table points to ma_smalltable for small tables, else to
|
|
* additional malloc'ed memory. ma_table is never NULL! This rule
|
|
* saves repeated runtime null-tests in the workhorse getitem and
|
|
* setitem calls.
|
|
*/
|
|
PyDictEntry *ma_table;
|
|
PyDictEntry *(*ma_lookup)(PyDictObject *mp, PyObject *key, long hash);
|
|
PyDictEntry ma_smalltable[PyDict_MINSIZE];
|
|
};
|
|
|
|
extern DL_IMPORT(PyTypeObject) PyDict_Type;
|
|
|
|
#define PyDict_Check(op) PyObject_TypeCheck(op, &PyDict_Type)
|
|
|
|
extern DL_IMPORT(PyObject *) PyDict_New(void);
|
|
extern DL_IMPORT(PyObject *) PyDict_GetItem(PyObject *mp, PyObject *key);
|
|
extern DL_IMPORT(int) PyDict_SetItem(PyObject *mp, PyObject *key, PyObject *item);
|
|
extern DL_IMPORT(int) PyDict_DelItem(PyObject *mp, PyObject *key);
|
|
extern DL_IMPORT(void) PyDict_Clear(PyObject *mp);
|
|
extern DL_IMPORT(int) PyDict_Next
|
|
(PyObject *mp, int *pos, PyObject **key, PyObject **value);
|
|
extern DL_IMPORT(PyObject *) PyDict_Keys(PyObject *mp);
|
|
extern DL_IMPORT(PyObject *) PyDict_Values(PyObject *mp);
|
|
extern DL_IMPORT(PyObject *) PyDict_Items(PyObject *mp);
|
|
extern DL_IMPORT(int) PyDict_Size(PyObject *mp);
|
|
extern DL_IMPORT(PyObject *) PyDict_Copy(PyObject *mp);
|
|
extern DL_IMPORT(int) PyDict_Update(PyObject *mp, PyObject *other);
|
|
|
|
|
|
extern DL_IMPORT(PyObject *) PyDict_GetItemString(PyObject *dp, char *key);
|
|
extern DL_IMPORT(int) PyDict_SetItemString(PyObject *dp, char *key, PyObject *item);
|
|
extern DL_IMPORT(int) PyDict_DelItemString(PyObject *dp, char *key);
|
|
|
|
#ifdef __cplusplus
|
|
}
|
|
#endif
|
|
#endif /* !Py_DICTOBJECT_H */
|