php-src/Zend/zend_hash.h
2003-06-10 20:04:29 +00:00

291 lines
13 KiB
C

/*
+----------------------------------------------------------------------+
| Zend Engine |
+----------------------------------------------------------------------+
| Copyright (c) 1998-2003 Zend Technologies Ltd. (http://www.zend.com) |
+----------------------------------------------------------------------+
| This source file is subject to version 2.00 of the Zend license, |
| that is bundled with this package in the file LICENSE, and is |
| available through the world-wide-web at the following url: |
| http://www.zend.com/license/2_00.txt. |
| If you did not receive a copy of the Zend license and are unable to |
| obtain it through the world-wide-web, please send a note to |
| license@zend.com so we can mail you a copy immediately. |
+----------------------------------------------------------------------+
| Authors: Andi Gutmans <andi@zend.com> |
| Zeev Suraski <zeev@zend.com> |
+----------------------------------------------------------------------+
*/
/* $Id$ */
#ifndef ZEND_HASH_H
#define ZEND_HASH_H
#include <sys/types.h>
#include "zend.h"
#define HASH_KEY_IS_STRING 1
#define HASH_KEY_IS_LONG 2
#define HASH_KEY_NON_EXISTANT 3
#define HASH_UPDATE (1<<0)
#define HASH_ADD (1<<1)
#define HASH_NEXT_INSERT (1<<2)
#define HASH_DEL_KEY 0
#define HASH_DEL_INDEX 1
typedef ulong (*hash_func_t)(char *arKey, uint nKeyLength);
typedef int (*compare_func_t)(const void *, const void * TSRMLS_DC);
typedef void (*sort_func_t)(void *, size_t, register size_t, compare_func_t TSRMLS_DC);
typedef void (*dtor_func_t)(void *pDest);
typedef void (*copy_ctor_func_t)(void *pElement);
typedef void (*copy_ctor_param_func_t)(void *pElement, void *pParam);
struct _hashtable;
typedef struct bucket {
ulong h; /* Used for numeric indexing */
uint nKeyLength;
void *pData;
void *pDataPtr;
struct bucket *pListNext;
struct bucket *pListLast;
struct bucket *pNext;
struct bucket *pLast;
char arKey[1]; /* Must be last element */
} Bucket;
typedef struct _hashtable {
uint nTableSize;
uint nTableMask;
uint nNumOfElements;
ulong nNextFreeElement;
Bucket *pInternalPointer; /* Used for element traversal */
Bucket *pListHead;
Bucket *pListTail;
Bucket **arBuckets;
dtor_func_t pDestructor;
zend_bool persistent;
unsigned char nApplyCount;
zend_bool bApplyProtection;
#if ZEND_DEBUG
int inconsistent;
#endif
} HashTable;
typedef struct _zend_hash_key {
char *arKey;
uint nKeyLength;
ulong h;
} zend_hash_key;
typedef zend_bool (*merge_checker_func_t)(HashTable *target_ht, void *source_data, zend_hash_key *hash_key, void *pParam);
typedef Bucket* HashPosition;
BEGIN_EXTERN_C()
/* startup/shutdown */
ZEND_API int _zend_hash_init(HashTable *ht, uint nSize, hash_func_t pHashFunction, dtor_func_t pDestructor, zend_bool persistent ZEND_FILE_LINE_DC);
ZEND_API int _zend_hash_init_ex(HashTable *ht, uint nSize, hash_func_t pHashFunction, dtor_func_t pDestructor, zend_bool persistent, zend_bool bApplyProtection ZEND_FILE_LINE_DC);
ZEND_API void zend_hash_destroy(HashTable *ht);
ZEND_API void zend_hash_clean(HashTable *ht);
#define zend_hash_init(ht, nSize, pHashFunction, pDestructor, persistent) _zend_hash_init((ht), (nSize), (pHashFunction), (pDestructor), (persistent) ZEND_FILE_LINE_CC)
#define zend_hash_init_ex(ht, nSize, pHashFunction, pDestructor, persistent, bApplyProtection) _zend_hash_init_ex((ht), (nSize), (pHashFunction), (pDestructor), (persistent), (bApplyProtection) ZEND_FILE_LINE_CC)
/* additions/updates/changes */
ZEND_API int zend_hash_add_or_update(HashTable *ht, char *arKey, uint nKeyLength, void *pData, uint nDataSize, void **pDest, int flag);
#define zend_hash_update(ht, arKey, nKeyLength, pData, nDataSize, pDest) \
zend_hash_add_or_update(ht, arKey, nKeyLength, pData, nDataSize, pDest, HASH_UPDATE)
#define zend_hash_add(ht, arKey, nKeyLength, pData, nDataSize, pDest) \
zend_hash_add_or_update(ht, arKey, nKeyLength, pData, nDataSize, pDest, HASH_ADD)
ZEND_API int zend_hash_quick_add_or_update(HashTable *ht, char *arKey, uint nKeyLength, ulong h, void *pData, uint nDataSize, void **pDest, int flag);
#define zend_hash_quick_update(ht, arKey, nKeyLength, h, pData, nDataSize, pDest) \
zend_hash_quick_add_or_update(ht, arKey, nKeyLength, h, pData, nDataSize, pDest, HASH_UPDATE)
#define zend_hash_quick_add(ht, arKey, nKeyLength, h, pData, nDataSize, pDest) \
zend_hash_quick_add_or_update(ht, arKey, nKeyLength, h, pData, nDataSize, pDest, HASH_ADD)
ZEND_API int zend_hash_index_update_or_next_insert(HashTable *ht, ulong h, void *pData, uint nDataSize, void **pDest, int flag);
#define zend_hash_index_update(ht, h, pData, nDataSize, pDest) \
zend_hash_index_update_or_next_insert(ht, h, pData, nDataSize, pDest, HASH_UPDATE)
#define zend_hash_next_index_insert(ht, pData, nDataSize, pDest) \
zend_hash_index_update_or_next_insert(ht, 0, pData, nDataSize, pDest, HASH_NEXT_INSERT)
ZEND_API int zend_hash_add_empty_element(HashTable *ht, char *arKey, uint nKeyLength);
#define ZEND_HASH_APPLY_KEEP 0
#define ZEND_HASH_APPLY_REMOVE 1<<0
#define ZEND_HASH_APPLY_STOP 1<<1
typedef int (*apply_func_t)(void *pDest TSRMLS_DC);
typedef int (*apply_func_arg_t)(void *pDest, void *argument TSRMLS_DC);
typedef int (*apply_func_args_t)(void *pDest, int num_args, va_list args, zend_hash_key *hash_key);
ZEND_API void zend_hash_graceful_destroy(HashTable *ht);
ZEND_API void zend_hash_graceful_reverse_destroy(HashTable *ht);
ZEND_API void zend_hash_apply(HashTable *ht, apply_func_t apply_func TSRMLS_DC);
ZEND_API void zend_hash_apply_with_argument(HashTable *ht, apply_func_arg_t apply_func, void * TSRMLS_DC);
ZEND_API void zend_hash_apply_with_arguments(HashTable *ht, apply_func_args_t apply_func, int, ...);
/* This function should be used with special care (in other words,
* it should usually not be used). When used with the ZEND_HASH_APPLY_STOP
* return value, it assumes things about the order of the elements in the hash.
* Also, it does not provide the same kind of reentrancy protection that
* the standard apply functions do.
*/
ZEND_API void zend_hash_reverse_apply(HashTable *ht, apply_func_t apply_func TSRMLS_DC);
/* Deletes */
ZEND_API int zend_hash_del_key_or_index(HashTable *ht, char *arKey, uint nKeyLength, ulong h, int flag);
#define zend_hash_del(ht, arKey, nKeyLength) \
zend_hash_del_key_or_index(ht, arKey, nKeyLength, 0, HASH_DEL_KEY)
#define zend_hash_index_del(ht, h) \
zend_hash_del_key_or_index(ht, NULL, 0, h, HASH_DEL_INDEX)
ZEND_API ulong zend_get_hash_value(char *arKey, uint nKeyLength);
/* Data retreival */
ZEND_API int zend_hash_find(HashTable *ht, char *arKey, uint nKeyLength, void **pData);
ZEND_API int zend_hash_quick_find(HashTable *ht, char *arKey, uint nKeyLength, ulong h, void **pData);
ZEND_API int zend_hash_index_find(HashTable *ht, ulong h, void **pData);
/* Misc */
ZEND_API int zend_hash_exists(HashTable *ht, char *arKey, uint nKeyLength);
ZEND_API int zend_hash_quick_exists(HashTable *ht, char *arKey, uint nKeyLength, ulong h);
ZEND_API int zend_hash_index_exists(HashTable *ht, ulong h);
ZEND_API ulong zend_hash_next_free_element(HashTable *ht);
/* traversing */
ZEND_API int zend_hash_move_forward_ex(HashTable *ht, HashPosition *pos);
ZEND_API int zend_hash_move_backwards_ex(HashTable *ht, HashPosition *pos);
ZEND_API int zend_hash_get_current_key_ex(HashTable *ht, char **str_index, uint *str_length, ulong *num_index, zend_bool duplicate, HashPosition *pos);
ZEND_API int zend_hash_get_current_key_type_ex(HashTable *ht, HashPosition *pos);
ZEND_API int zend_hash_get_current_data_ex(HashTable *ht, void **pData, HashPosition *pos);
ZEND_API void zend_hash_internal_pointer_reset_ex(HashTable *ht, HashPosition *pos);
ZEND_API void zend_hash_internal_pointer_end_ex(HashTable *ht, HashPosition *pos);
#define zend_hash_move_forward(ht) \
zend_hash_move_forward_ex(ht, NULL)
#define zend_hash_move_backwards(ht) \
zend_hash_move_backwards_ex(ht, NULL)
#define zend_hash_get_current_key(ht, str_index, num_index, duplicate) \
zend_hash_get_current_key_ex(ht, str_index, NULL, num_index, duplicate, NULL)
#define zend_hash_get_current_key_type(ht) \
zend_hash_get_current_key_type_ex(ht, NULL)
#define zend_hash_get_current_data(ht, pData) \
zend_hash_get_current_data_ex(ht, pData, NULL)
#define zend_hash_internal_pointer_reset(ht) \
zend_hash_internal_pointer_reset_ex(ht, NULL)
#define zend_hash_internal_pointer_end(ht) \
zend_hash_internal_pointer_end_ex(ht, NULL)
/* Copying, merging and sorting */
ZEND_API void zend_hash_copy(HashTable *target, HashTable *source, copy_ctor_func_t pCopyConstructor, void *tmp, uint size);
ZEND_API void zend_hash_merge(HashTable *target, HashTable *source, copy_ctor_func_t pCopyConstructor, void *tmp, uint size, int overwrite);
ZEND_API void zend_hash_merge_ex(HashTable *target, HashTable *source, copy_ctor_func_t pCopyConstructor, uint size, merge_checker_func_t pMergeSource, void *pParam);
ZEND_API int zend_hash_sort(HashTable *ht, sort_func_t sort_func, compare_func_t compare_func, int renumber TSRMLS_DC);
ZEND_API int zend_hash_compare(HashTable *ht1, HashTable *ht2, compare_func_t compar, zend_bool ordered TSRMLS_DC);
ZEND_API int zend_hash_minmax(HashTable *ht, compare_func_t compar, int flag, void **pData TSRMLS_DC);
ZEND_API int zend_hash_num_elements(HashTable *ht);
ZEND_API int zend_hash_rehash(HashTable *ht);
/*
* DJBX33A (Daniel J. Bernstein, Times 33 with Addition)
*
* This is Daniel J. Bernstein's popular `times 33' hash function as
* posted by him years ago on comp.lang.c. It basically uses a function
* like ``hash(i) = hash(i-1) * 33 + str[i]''. This is one of the best
* known hash functions for strings. Because it is both computed very
* fast and distributes very well.
*
* The magic of number 33, i.e. why it works better than many other
* constants, prime or not, has never been adequately explained by
* anyone. So I try an explanation: if one experimentally tests all
* multipliers between 1 and 256 (as RSE did now) one detects that even
* numbers are not useable at all. The remaining 128 odd numbers
* (except for the number 1) work more or less all equally well. They
* all distribute in an acceptable way and this way fill a hash table
* with an average percent of approx. 86%.
*
* If one compares the Chi^2 values of the variants, the number 33 not
* even has the best value. But the number 33 and a few other equally
* good numbers like 17, 31, 63, 127 and 129 have nevertheless a great
* advantage to the remaining numbers in the large set of possible
* multipliers: their multiply operation can be replaced by a faster
* operation based on just one shift plus either a single addition
* or subtraction operation. And because a hash function has to both
* distribute good _and_ has to be very fast to compute, those few
* numbers should be preferred and seems to be the reason why Daniel J.
* Bernstein also preferred it.
*
*
* -- Ralf S. Engelschall <rse@engelschall.com>
*/
static inline ulong zend_inline_hash_func(char *arKey, uint nKeyLength)
{
register ulong hash = 5381;
/* variant with the hash unrolled eight times */
for (; nKeyLength >= 8; nKeyLength -= 8) {
hash = ((hash << 5) + hash) + *arKey++;
hash = ((hash << 5) + hash) + *arKey++;
hash = ((hash << 5) + hash) + *arKey++;
hash = ((hash << 5) + hash) + *arKey++;
hash = ((hash << 5) + hash) + *arKey++;
hash = ((hash << 5) + hash) + *arKey++;
hash = ((hash << 5) + hash) + *arKey++;
hash = ((hash << 5) + hash) + *arKey++;
}
switch (nKeyLength) {
case 7: hash = ((hash << 5) + hash) + *arKey++; /* fallthrough... */
case 6: hash = ((hash << 5) + hash) + *arKey++; /* fallthrough... */
case 5: hash = ((hash << 5) + hash) + *arKey++; /* fallthrough... */
case 4: hash = ((hash << 5) + hash) + *arKey++; /* fallthrough... */
case 3: hash = ((hash << 5) + hash) + *arKey++; /* fallthrough... */
case 2: hash = ((hash << 5) + hash) + *arKey++; /* fallthrough... */
case 1: hash = ((hash << 5) + hash) + *arKey++; break;
case 0: break;
EMPTY_SWITCH_DEFAULT_CASE()
}
return hash;
}
ZEND_API ulong zend_hash_func(char *arKey, uint nKeyLength);
#if ZEND_DEBUG
/* debug */
void zend_hash_display_pListTail(HashTable *ht);
void zend_hash_display(HashTable *ht);
#endif
END_EXTERN_C()
#define ZEND_INIT_SYMTABLE(ht) \
ZEND_INIT_SYMTABLE_EX(ht, 2, 0)
#define ZEND_INIT_SYMTABLE_EX(ht, n, persistent) \
zend_hash_init(ht, n, NULL, ZVAL_PTR_DTOR, persistent)
#endif /* ZEND_HASH_H */
/*
* Local variables:
* tab-width: 4
* c-basic-offset: 4
* indent-tabs-mode: t
* End:
*/