1/*
2   +----------------------------------------------------------------------+
3   | Zend Engine                                                          |
4   +----------------------------------------------------------------------+
5   | Copyright (c) 1998-2013 Zend Technologies Ltd. (http://www.zend.com) |
6   +----------------------------------------------------------------------+
7   | This source file is subject to version 2.00 of the Zend license,     |
8   | that is bundled with this package in the file LICENSE, and is        |
9   | available through the world-wide-web at the following url:           |
10   | http://www.zend.com/license/2_00.txt.                                |
11   | If you did not receive a copy of the Zend license and are unable to  |
12   | obtain it through the world-wide-web, please send a note to          |
13   | license@zend.com so we can mail you a copy immediately.              |
14   +----------------------------------------------------------------------+
15   | Authors: Andi Gutmans <andi@zend.com>                                |
16   |          Zeev Suraski <zeev@zend.com>                                |
17   +----------------------------------------------------------------------+
18*/
19
20/* $Id$ */
21
22#ifndef ZEND_HASH_H
23#define ZEND_HASH_H
24
25#include <sys/types.h>
26#include "zend.h"
27
28#define HASH_KEY_IS_STRING 1
29#define HASH_KEY_IS_LONG 2
30#define HASH_KEY_NON_EXISTANT 3
31
32#define HASH_UPDATE         (1<<0)
33#define HASH_ADD            (1<<1)
34#define HASH_NEXT_INSERT    (1<<2)
35
36#define HASH_DEL_KEY 0
37#define HASH_DEL_INDEX 1
38#define HASH_DEL_KEY_QUICK 2
39
40#define HASH_UPDATE_KEY_IF_NONE    0
41#define HASH_UPDATE_KEY_IF_BEFORE  1
42#define HASH_UPDATE_KEY_IF_AFTER   2
43#define HASH_UPDATE_KEY_ANYWAY     3
44
45typedef ulong (*hash_func_t)(const char *arKey, uint nKeyLength);
46typedef int  (*compare_func_t)(const void *, const void * TSRMLS_DC);
47typedef void (*sort_func_t)(void *, size_t, register size_t, compare_func_t TSRMLS_DC);
48typedef void (*dtor_func_t)(void *pDest);
49typedef void (*copy_ctor_func_t)(void *pElement);
50typedef void (*copy_ctor_param_func_t)(void *pElement, void *pParam);
51
52struct _hashtable;
53
54typedef struct bucket {
55    ulong h;                        /* Used for numeric indexing */
56    uint nKeyLength;
57    void *pData;
58    void *pDataPtr;
59    struct bucket *pListNext;
60    struct bucket *pListLast;
61    struct bucket *pNext;
62    struct bucket *pLast;
63    char arKey[1]; /* Must be last element */
64} Bucket;
65
66typedef struct _hashtable {
67    uint nTableSize;
68    uint nTableMask;
69    uint nNumOfElements;
70    ulong nNextFreeElement;
71    Bucket *pInternalPointer;   /* Used for element traversal */
72    Bucket *pListHead;
73    Bucket *pListTail;
74    Bucket **arBuckets;
75    dtor_func_t pDestructor;
76    zend_bool persistent;
77    unsigned char nApplyCount;
78    zend_bool bApplyProtection;
79#if ZEND_DEBUG
80    int inconsistent;
81#endif
82} HashTable;
83
84
85typedef struct _zend_hash_key {
86    char *arKey;
87    uint nKeyLength;
88    ulong h;
89} zend_hash_key;
90
91
92typedef zend_bool (*merge_checker_func_t)(HashTable *target_ht, void *source_data, zend_hash_key *hash_key, void *pParam);
93
94typedef Bucket* HashPosition;
95
96BEGIN_EXTERN_C()
97
98/* startup/shutdown */
99ZEND_API int _zend_hash_init(HashTable *ht, uint nSize, hash_func_t pHashFunction, dtor_func_t pDestructor, zend_bool persistent ZEND_FILE_LINE_DC);
100ZEND_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);
101ZEND_API void zend_hash_destroy(HashTable *ht);
102ZEND_API void zend_hash_clean(HashTable *ht);
103#define zend_hash_init(ht, nSize, pHashFunction, pDestructor, persistent)                       _zend_hash_init((ht), (nSize), (pHashFunction), (pDestructor), (persistent) ZEND_FILE_LINE_CC)
104#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)
105
106/* additions/updates/changes */
107ZEND_API int _zend_hash_add_or_update(HashTable *ht, const char *arKey, uint nKeyLength, void *pData, uint nDataSize, void **pDest, int flag ZEND_FILE_LINE_DC);
108#define zend_hash_update(ht, arKey, nKeyLength, pData, nDataSize, pDest) \
109        _zend_hash_add_or_update(ht, arKey, nKeyLength, pData, nDataSize, pDest, HASH_UPDATE ZEND_FILE_LINE_CC)
110#define zend_hash_add(ht, arKey, nKeyLength, pData, nDataSize, pDest) \
111        _zend_hash_add_or_update(ht, arKey, nKeyLength, pData, nDataSize, pDest, HASH_ADD ZEND_FILE_LINE_CC)
112
113ZEND_API int _zend_hash_quick_add_or_update(HashTable *ht, const char *arKey, uint nKeyLength, ulong h, void *pData, uint nDataSize, void **pDest, int flag ZEND_FILE_LINE_DC);
114#define zend_hash_quick_update(ht, arKey, nKeyLength, h, pData, nDataSize, pDest) \
115        _zend_hash_quick_add_or_update(ht, arKey, nKeyLength, h, pData, nDataSize, pDest, HASH_UPDATE ZEND_FILE_LINE_CC)
116#define zend_hash_quick_add(ht, arKey, nKeyLength, h, pData, nDataSize, pDest) \
117        _zend_hash_quick_add_or_update(ht, arKey, nKeyLength, h, pData, nDataSize, pDest, HASH_ADD ZEND_FILE_LINE_CC)
118
119ZEND_API int _zend_hash_index_update_or_next_insert(HashTable *ht, ulong h, void *pData, uint nDataSize, void **pDest, int flag ZEND_FILE_LINE_DC);
120#define zend_hash_index_update(ht, h, pData, nDataSize, pDest) \
121        _zend_hash_index_update_or_next_insert(ht, h, pData, nDataSize, pDest, HASH_UPDATE ZEND_FILE_LINE_CC)
122#define zend_hash_next_index_insert(ht, pData, nDataSize, pDest) \
123        _zend_hash_index_update_or_next_insert(ht, 0, pData, nDataSize, pDest, HASH_NEXT_INSERT ZEND_FILE_LINE_CC)
124
125ZEND_API int zend_hash_add_empty_element(HashTable *ht, const char *arKey, uint nKeyLength);
126
127
128#define ZEND_HASH_APPLY_KEEP                0
129#define ZEND_HASH_APPLY_REMOVE              1<<0
130#define ZEND_HASH_APPLY_STOP                1<<1
131
132typedef int (*apply_func_t)(void *pDest TSRMLS_DC);
133typedef int (*apply_func_arg_t)(void *pDest, void *argument TSRMLS_DC);
134typedef int (*apply_func_args_t)(void *pDest TSRMLS_DC, int num_args, va_list args, zend_hash_key *hash_key);
135
136ZEND_API void zend_hash_graceful_destroy(HashTable *ht);
137ZEND_API void zend_hash_graceful_reverse_destroy(HashTable *ht);
138ZEND_API void zend_hash_apply(HashTable *ht, apply_func_t apply_func TSRMLS_DC);
139ZEND_API void zend_hash_apply_with_argument(HashTable *ht, apply_func_arg_t apply_func, void * TSRMLS_DC);
140ZEND_API void zend_hash_apply_with_arguments(HashTable *ht TSRMLS_DC, apply_func_args_t apply_func, int, ...);
141
142/* This function should be used with special care (in other words,
143 * it should usually not be used).  When used with the ZEND_HASH_APPLY_STOP
144 * return value, it assumes things about the order of the elements in the hash.
145 * Also, it does not provide the same kind of reentrancy protection that
146 * the standard apply functions do.
147 */
148ZEND_API void zend_hash_reverse_apply(HashTable *ht, apply_func_t apply_func TSRMLS_DC);
149
150
151/* Deletes */
152ZEND_API int zend_hash_del_key_or_index(HashTable *ht, const char *arKey, uint nKeyLength, ulong h, int flag);
153#define zend_hash_del(ht, arKey, nKeyLength) \
154        zend_hash_del_key_or_index(ht, arKey, nKeyLength, 0, HASH_DEL_KEY)
155#define zend_hash_quick_del(ht, arKey, nKeyLength, h) \
156        zend_hash_del_key_or_index(ht, arKey, nKeyLength, h, HASH_DEL_KEY_QUICK)
157#define zend_hash_index_del(ht, h) \
158        zend_hash_del_key_or_index(ht, NULL, 0, h, HASH_DEL_INDEX)
159
160ZEND_API ulong zend_get_hash_value(const char *arKey, uint nKeyLength);
161
162/* Data retreival */
163ZEND_API int zend_hash_find(const HashTable *ht, const char *arKey, uint nKeyLength, void **pData);
164ZEND_API int zend_hash_quick_find(const HashTable *ht, const char *arKey, uint nKeyLength, ulong h, void **pData);
165ZEND_API int zend_hash_index_find(const HashTable *ht, ulong h, void **pData);
166
167/* Misc */
168ZEND_API int zend_hash_exists(const HashTable *ht, const char *arKey, uint nKeyLength);
169ZEND_API int zend_hash_quick_exists(const HashTable *ht, const char *arKey, uint nKeyLength, ulong h);
170ZEND_API int zend_hash_index_exists(const HashTable *ht, ulong h);
171ZEND_API ulong zend_hash_next_free_element(const HashTable *ht);
172
173
174/* traversing */
175#define zend_hash_has_more_elements_ex(ht, pos) \
176    (zend_hash_get_current_key_type_ex(ht, pos) == HASH_KEY_NON_EXISTANT ? FAILURE : SUCCESS)
177ZEND_API int zend_hash_move_forward_ex(HashTable *ht, HashPosition *pos);
178ZEND_API int zend_hash_move_backwards_ex(HashTable *ht, HashPosition *pos);
179ZEND_API int zend_hash_get_current_key_ex(const HashTable *ht, char **str_index, uint *str_length, ulong *num_index, zend_bool duplicate, HashPosition *pos);
180ZEND_API int zend_hash_get_current_key_type_ex(HashTable *ht, HashPosition *pos);
181ZEND_API int zend_hash_get_current_data_ex(HashTable *ht, void **pData, HashPosition *pos);
182ZEND_API void zend_hash_internal_pointer_reset_ex(HashTable *ht, HashPosition *pos);
183ZEND_API void zend_hash_internal_pointer_end_ex(HashTable *ht, HashPosition *pos);
184ZEND_API int zend_hash_update_current_key_ex(HashTable *ht, int key_type, const char *str_index, uint str_length, ulong num_index, int mode, HashPosition *pos);
185
186typedef struct _HashPointer {
187    HashPosition pos;
188    ulong h;
189} HashPointer;
190
191ZEND_API int zend_hash_get_pointer(const HashTable *ht, HashPointer *ptr);
192ZEND_API int zend_hash_set_pointer(HashTable *ht, const HashPointer *ptr);
193
194#define zend_hash_has_more_elements(ht) \
195    zend_hash_has_more_elements_ex(ht, NULL)
196#define zend_hash_move_forward(ht) \
197    zend_hash_move_forward_ex(ht, NULL)
198#define zend_hash_move_backwards(ht) \
199    zend_hash_move_backwards_ex(ht, NULL)
200#define zend_hash_get_current_key(ht, str_index, num_index, duplicate) \
201    zend_hash_get_current_key_ex(ht, str_index, NULL, num_index, duplicate, NULL)
202#define zend_hash_get_current_key_type(ht) \
203    zend_hash_get_current_key_type_ex(ht, NULL)
204#define zend_hash_get_current_data(ht, pData) \
205    zend_hash_get_current_data_ex(ht, pData, NULL)
206#define zend_hash_internal_pointer_reset(ht) \
207    zend_hash_internal_pointer_reset_ex(ht, NULL)
208#define zend_hash_internal_pointer_end(ht) \
209    zend_hash_internal_pointer_end_ex(ht, NULL)
210#define zend_hash_update_current_key(ht, key_type, str_index, str_length, num_index) \
211    zend_hash_update_current_key_ex(ht, key_type, str_index, str_length, num_index, HASH_UPDATE_KEY_ANYWAY, NULL)
212
213/* Copying, merging and sorting */
214ZEND_API void zend_hash_copy(HashTable *target, HashTable *source, copy_ctor_func_t pCopyConstructor, void *tmp, uint size);
215ZEND_API void _zend_hash_merge(HashTable *target, HashTable *source, copy_ctor_func_t pCopyConstructor, void *tmp, uint size, int overwrite ZEND_FILE_LINE_DC);
216ZEND_API void zend_hash_merge_ex(HashTable *target, HashTable *source, copy_ctor_func_t pCopyConstructor, uint size, merge_checker_func_t pMergeSource, void *pParam);
217ZEND_API int zend_hash_sort(HashTable *ht, sort_func_t sort_func, compare_func_t compare_func, int renumber TSRMLS_DC);
218ZEND_API int zend_hash_compare(HashTable *ht1, HashTable *ht2, compare_func_t compar, zend_bool ordered TSRMLS_DC);
219ZEND_API int zend_hash_minmax(const HashTable *ht, compare_func_t compar, int flag, void **pData TSRMLS_DC);
220
221#define zend_hash_merge(target, source, pCopyConstructor, tmp, size, overwrite)                 \
222    _zend_hash_merge(target, source, pCopyConstructor, tmp, size, overwrite ZEND_FILE_LINE_CC)
223
224ZEND_API int zend_hash_num_elements(const HashTable *ht);
225
226ZEND_API int zend_hash_rehash(HashTable *ht);
227
228/*
229 * DJBX33A (Daniel J. Bernstein, Times 33 with Addition)
230 *
231 * This is Daniel J. Bernstein's popular `times 33' hash function as
232 * posted by him years ago on comp.lang.c. It basically uses a function
233 * like ``hash(i) = hash(i-1) * 33 + str[i]''. This is one of the best
234 * known hash functions for strings. Because it is both computed very
235 * fast and distributes very well.
236 *
237 * The magic of number 33, i.e. why it works better than many other
238 * constants, prime or not, has never been adequately explained by
239 * anyone. So I try an explanation: if one experimentally tests all
240 * multipliers between 1 and 256 (as RSE did now) one detects that even
241 * numbers are not useable at all. The remaining 128 odd numbers
242 * (except for the number 1) work more or less all equally well. They
243 * all distribute in an acceptable way and this way fill a hash table
244 * with an average percent of approx. 86%.
245 *
246 * If one compares the Chi^2 values of the variants, the number 33 not
247 * even has the best value. But the number 33 and a few other equally
248 * good numbers like 17, 31, 63, 127 and 129 have nevertheless a great
249 * advantage to the remaining numbers in the large set of possible
250 * multipliers: their multiply operation can be replaced by a faster
251 * operation based on just one shift plus either a single addition
252 * or subtraction operation. And because a hash function has to both
253 * distribute good _and_ has to be very fast to compute, those few
254 * numbers should be preferred and seems to be the reason why Daniel J.
255 * Bernstein also preferred it.
256 *
257 *
258 *                  -- Ralf S. Engelschall <rse@engelschall.com>
259 */
260
261static inline ulong zend_inline_hash_func(const char *arKey, uint nKeyLength)
262{
263    register ulong hash = 5381;
264
265    /* variant with the hash unrolled eight times */
266    for (; nKeyLength >= 8; nKeyLength -= 8) {
267        hash = ((hash << 5) + hash) + *arKey++;
268        hash = ((hash << 5) + hash) + *arKey++;
269        hash = ((hash << 5) + hash) + *arKey++;
270        hash = ((hash << 5) + hash) + *arKey++;
271        hash = ((hash << 5) + hash) + *arKey++;
272        hash = ((hash << 5) + hash) + *arKey++;
273        hash = ((hash << 5) + hash) + *arKey++;
274        hash = ((hash << 5) + hash) + *arKey++;
275    }
276    switch (nKeyLength) {
277        case 7: hash = ((hash << 5) + hash) + *arKey++; /* fallthrough... */
278        case 6: hash = ((hash << 5) + hash) + *arKey++; /* fallthrough... */
279        case 5: hash = ((hash << 5) + hash) + *arKey++; /* fallthrough... */
280        case 4: hash = ((hash << 5) + hash) + *arKey++; /* fallthrough... */
281        case 3: hash = ((hash << 5) + hash) + *arKey++; /* fallthrough... */
282        case 2: hash = ((hash << 5) + hash) + *arKey++; /* fallthrough... */
283        case 1: hash = ((hash << 5) + hash) + *arKey++; break;
284        case 0: break;
285EMPTY_SWITCH_DEFAULT_CASE()
286    }
287    return hash;
288}
289
290
291ZEND_API ulong zend_hash_func(const char *arKey, uint nKeyLength);
292
293#if ZEND_DEBUG
294/* debug */
295void zend_hash_display_pListTail(const HashTable *ht);
296void zend_hash_display(const HashTable *ht);
297#endif
298
299END_EXTERN_C()
300
301#define ZEND_INIT_SYMTABLE(ht)                              \
302    ZEND_INIT_SYMTABLE_EX(ht, 2, 0)
303
304#define ZEND_INIT_SYMTABLE_EX(ht, n, persistent)            \
305    zend_hash_init(ht, n, NULL, ZVAL_PTR_DTOR, persistent)
306
307#define ZEND_HANDLE_NUMERIC(key, length, func) do {                         \
308    register const char *tmp = key;                                         \
309                                                                            \
310    if (*tmp == '-') {                                                      \
311        tmp++;                                                              \
312    }                                                                       \
313    if (*tmp >= '0' && *tmp <= '9') { /* possibly a numeric index */        \
314        const char *end = key + length - 1;                                 \
315        ulong idx;                                                          \
316                                                                            \
317        if ((*end != '\0') /* not a null terminated string */               \
318         || (*tmp == '0' && length > 2) /* numbers with leading zeros */    \
319         || (end - tmp > MAX_LENGTH_OF_LONG - 1) /* number too long */      \
320         || (SIZEOF_LONG == 4 &&                                            \
321             end - tmp == MAX_LENGTH_OF_LONG - 1 &&                         \
322             *tmp > '2')) { /* overflow */                                  \
323            break;                                                          \
324        }                                                                   \
325        idx = (*tmp - '0');                                                 \
326        while (++tmp != end && *tmp >= '0' && *tmp <= '9') {                \
327            idx = (idx * 10) + (*tmp - '0');                                \
328        }                                                                   \
329        if (tmp == end) {                                                   \
330            if (*key == '-') {                                              \
331                if (idx-1 > LONG_MAX) { /* overflow */                      \
332                    break;                                                  \
333                }                                                           \
334                idx = 0 - idx;                                                  \
335            } else if (idx > LONG_MAX) { /* overflow */                     \
336                break;                                                      \
337            }                                                               \
338            return func;                                                    \
339        }                                                                   \
340    }                                                                       \
341} while (0)
342
343static inline int zend_symtable_update(HashTable *ht, const char *arKey, uint nKeyLength, void *pData, uint nDataSize, void **pDest)                    \
344{
345    ZEND_HANDLE_NUMERIC(arKey, nKeyLength, zend_hash_index_update(ht, idx, pData, nDataSize, pDest));
346    return zend_hash_update(ht, arKey, nKeyLength, pData, nDataSize, pDest);
347}
348
349
350static inline int zend_symtable_del(HashTable *ht, const char *arKey, uint nKeyLength)
351{
352    ZEND_HANDLE_NUMERIC(arKey, nKeyLength, zend_hash_index_del(ht, idx));
353    return zend_hash_del(ht, arKey, nKeyLength);
354}
355
356
357static inline int zend_symtable_find(HashTable *ht, const char *arKey, uint nKeyLength, void **pData)
358{
359    ZEND_HANDLE_NUMERIC(arKey, nKeyLength, zend_hash_index_find(ht, idx, pData));
360    return zend_hash_find(ht, arKey, nKeyLength, pData);
361}
362
363
364static inline int zend_symtable_exists(HashTable *ht, const char *arKey, uint nKeyLength)
365{
366    ZEND_HANDLE_NUMERIC(arKey, nKeyLength, zend_hash_index_exists(ht, idx));
367    return zend_hash_exists(ht, arKey, nKeyLength);
368}
369
370static inline int zend_symtable_update_current_key_ex(HashTable *ht, const char *arKey, uint nKeyLength, int mode, HashPosition *pos)
371{
372    ZEND_HANDLE_NUMERIC(arKey, nKeyLength, zend_hash_update_current_key_ex(ht, HASH_KEY_IS_LONG, NULL, 0, idx, mode, pos));
373    return zend_hash_update_current_key_ex(ht, HASH_KEY_IS_STRING, arKey, nKeyLength, 0, mode, pos);
374}
375#define zend_symtable_update_current_key(ht,arKey,nKeyLength,mode) \
376    zend_symtable_update_current_key_ex(ht, arKey, nKeyLength, mode, NULL)
377
378
379#endif                          /* ZEND_HASH_H */
380
381/*
382 * Local variables:
383 * tab-width: 4
384 * c-basic-offset: 4
385 * indent-tabs-mode: t
386 * End:
387 */
388