cpython/Include/internal/pycore_hashtable.h
Victor Stinner 5b0a30354d
bpo-40609: _Py_hashtable_t values become void* (GH-20065)
_Py_hashtable_t values become regular "void *" pointers.

* Add _Py_hashtable_entry_t.data member
* Remove _Py_hashtable_t.data_size member
* Remove _Py_hashtable_t.get_func member. It is no longer needed
  to specialize _Py_hashtable_get() for a specific value size, since
  all entries now have the same size (void*).
* Remove the following macros:

  * _Py_HASHTABLE_GET()
  * _Py_HASHTABLE_SET()
  * _Py_HASHTABLE_SET_NODATA()
  * _Py_HASHTABLE_POP()

* Rename _Py_hashtable_pop() to _Py_hashtable_steal()
* _Py_hashtable_foreach() callback now gets key and value rather than
  entry.
* Remove _Py_hashtable_value_destroy_func type. value_destroy_func
  callback now only has a single parameter: data (void*).
2020-05-13 04:40:30 +02:00

147 lines
4.1 KiB
C

#ifndef Py_INTERNAL_HASHTABLE_H
#define Py_INTERNAL_HASHTABLE_H
#ifdef __cplusplus
extern "C" {
#endif
#ifndef Py_BUILD_CORE
# error "this header requires Py_BUILD_CORE define"
#endif
/* Single linked list */
typedef struct _Py_slist_item_s {
struct _Py_slist_item_s *next;
} _Py_slist_item_t;
typedef struct {
_Py_slist_item_t *head;
} _Py_slist_t;
#define _Py_SLIST_ITEM_NEXT(ITEM) (((_Py_slist_item_t *)ITEM)->next)
#define _Py_SLIST_HEAD(SLIST) (((_Py_slist_t *)SLIST)->head)
/* _Py_hashtable: table entry */
typedef struct {
/* used by _Py_hashtable_t.buckets to link entries */
_Py_slist_item_t _Py_slist_item;
Py_uhash_t key_hash;
void *key;
void *value;
} _Py_hashtable_entry_t;
/* _Py_hashtable: prototypes */
/* Forward declaration */
struct _Py_hashtable_t;
typedef struct _Py_hashtable_t _Py_hashtable_t;
typedef Py_uhash_t (*_Py_hashtable_hash_func) (const void *key);
typedef int (*_Py_hashtable_compare_func) (const void *key1, const void *key2);
typedef void (*_Py_hashtable_destroy_func) (void *key);
typedef _Py_hashtable_entry_t* (*_Py_hashtable_get_entry_func)(_Py_hashtable_t *ht,
const void *key);
typedef struct {
/* allocate a memory block */
void* (*malloc) (size_t size);
/* release a memory block */
void (*free) (void *ptr);
} _Py_hashtable_allocator_t;
/* _Py_hashtable: table */
struct _Py_hashtable_t {
size_t num_buckets;
size_t entries; /* Total number of entries in the table. */
_Py_slist_t *buckets;
_Py_hashtable_get_entry_func get_entry_func;
_Py_hashtable_hash_func hash_func;
_Py_hashtable_compare_func compare_func;
_Py_hashtable_destroy_func key_destroy_func;
_Py_hashtable_destroy_func value_destroy_func;
_Py_hashtable_allocator_t alloc;
};
/* hash a pointer (void*) */
PyAPI_FUNC(Py_uhash_t) _Py_hashtable_hash_ptr(const void *key);
/* comparison using memcmp() */
PyAPI_FUNC(int) _Py_hashtable_compare_direct(
const void *key1,
const void *key2);
PyAPI_FUNC(_Py_hashtable_t *) _Py_hashtable_new(
_Py_hashtable_hash_func hash_func,
_Py_hashtable_compare_func compare_func);
PyAPI_FUNC(_Py_hashtable_t *) _Py_hashtable_new_full(
_Py_hashtable_hash_func hash_func,
_Py_hashtable_compare_func compare_func,
_Py_hashtable_destroy_func key_destroy_func,
_Py_hashtable_destroy_func value_destroy_func,
_Py_hashtable_allocator_t *allocator);
PyAPI_FUNC(void) _Py_hashtable_destroy(_Py_hashtable_t *ht);
PyAPI_FUNC(void) _Py_hashtable_clear(_Py_hashtable_t *ht);
typedef int (*_Py_hashtable_foreach_func) (_Py_hashtable_t *ht,
const void *key, const void *value,
void *user_data);
/* Call func() on each entry of the hashtable.
Iteration stops if func() result is non-zero, in this case it's the result
of the call. Otherwise, the function returns 0. */
PyAPI_FUNC(int) _Py_hashtable_foreach(
_Py_hashtable_t *ht,
_Py_hashtable_foreach_func func,
void *user_data);
PyAPI_FUNC(size_t) _Py_hashtable_size(const _Py_hashtable_t *ht);
/* Add a new entry to the hash. The key must not be present in the hash table.
Return 0 on success, -1 on memory error. */
PyAPI_FUNC(int) _Py_hashtable_set(
_Py_hashtable_t *ht,
const void *key,
void *value);
/* Get an entry.
Return NULL if the key does not exist. */
static inline _Py_hashtable_entry_t *
_Py_hashtable_get_entry(_Py_hashtable_t *ht, const void *key)
{
return ht->get_entry_func(ht, key);
}
/* Get value from an entry.
Return NULL if the entry is not found.
Use _Py_hashtable_get_entry() to distinguish entry value equal to NULL
and entry not found. */
extern void *_Py_hashtable_get(_Py_hashtable_t *ht, const void *key);
// Remove a key and its associated value without calling key and value destroy
// functions.
// Return the removed value if the key was found.
// Return NULL if the key was not found.
PyAPI_FUNC(void*) _Py_hashtable_steal(
_Py_hashtable_t *ht,
const void *key);
#ifdef __cplusplus
}
#endif
#endif /* !Py_INTERNAL_HASHTABLE_H */