dict.h 5.4 KB
Newer Older
A
antirez 已提交
1 2 3 4 5 6 7
/* Hash Tables Implementation.
 *
 * This file implements in memory hash tables with insert/del/replace/find/
 * get-random-element operations. Hash tables will auto resize if needed
 * tables of power of two in size are used, collisions are handled by
 * chaining. See the source code for more information... :)
 *
8
 * Copyright (c) 2006-2010, Salvatore Sanfilippo <antirez at gmail dot com>
A
antirez 已提交
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *   * Redistributions of source code must retain the above copyright notice,
 *     this list of conditions and the following disclaimer.
 *   * Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 *   * Neither the name of Redis nor the names of its contributors may be used
 *     to endorse or promote products derived from this software without
 *     specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#ifndef __DICT_H
#define __DICT_H

#define DICT_OK 0
#define DICT_ERR 1

/* Unused arguments generate annoying warnings... */
#define DICT_NOTUSED(V) ((void) V)

typedef struct dictEntry {
    void *key;
    void *val;
    struct dictEntry *next;
} dictEntry;

typedef struct dictType {
    unsigned int (*hashFunction)(const void *key);
    void *(*keyDup)(void *privdata, const void *key);
    void *(*valDup)(void *privdata, const void *obj);
    int (*keyCompare)(void *privdata, const void *key1, const void *key2);
    void (*keyDestructor)(void *privdata, void *key);
    void (*valDestructor)(void *privdata, void *obj);
} dictType;

60 61 62
/* This is our hash table structure. Every dictionary has two of this as we
 * implement incremental rehashing, for the old to the new table. */
typedef struct dictht {
A
antirez 已提交
63
    dictEntry **table;
64 65 66
    unsigned long size;
    unsigned long sizemask;
    unsigned long used;
67 68 69 70
} dictht;

typedef struct dict {
    dictType *type;
A
antirez 已提交
71
    void *privdata;
72 73 74
    dictht ht[2];
    int rehashidx; /* rehashing not in progress if rehashidx == -1 */
    int iterators; /* number of iterators currently running */
A
antirez 已提交
75 76 77
} dict;

typedef struct dictIterator {
78 79
    dict *d;
    int table;
A
antirez 已提交
80 81 82 83 84
    int index;
    dictEntry *entry, *nextEntry;
} dictIterator;

/* This is the initial size of every hash table */
85
#define DICT_HT_INITIAL_SIZE     4
A
antirez 已提交
86 87

/* ------------------------------- Macros ------------------------------------*/
88 89 90
#define dictFreeEntryVal(d, entry) \
    if ((d)->type->valDestructor) \
        (d)->type->valDestructor((d)->privdata, (entry)->val)
A
antirez 已提交
91

92 93 94
#define dictSetHashVal(d, entry, _val_) do { \
    if ((d)->type->valDup) \
        entry->val = (d)->type->valDup((d)->privdata, _val_); \
A
antirez 已提交
95 96 97 98
    else \
        entry->val = (_val_); \
} while(0)

99 100 101
#define dictFreeEntryKey(d, entry) \
    if ((d)->type->keyDestructor) \
        (d)->type->keyDestructor((d)->privdata, (entry)->key)
A
antirez 已提交
102

103 104 105
#define dictSetHashKey(d, entry, _key_) do { \
    if ((d)->type->keyDup) \
        entry->key = (d)->type->keyDup((d)->privdata, _key_); \
A
antirez 已提交
106 107 108 109
    else \
        entry->key = (_key_); \
} while(0)

110 111 112
#define dictCompareHashKeys(d, key1, key2) \
    (((d)->type->keyCompare) ? \
        (d)->type->keyCompare((d)->privdata, key1, key2) : \
A
antirez 已提交
113 114
        (key1) == (key2))

115
#define dictHashKey(d, key) (d)->type->hashFunction(key)
A
antirez 已提交
116 117 118

#define dictGetEntryKey(he) ((he)->key)
#define dictGetEntryVal(he) ((he)->val)
119 120 121
#define dictSlots(d) ((d)->ht[0].size+(d)->ht[1].size)
#define dictSize(d) ((d)->ht[0].used+(d)->ht[1].used)
#define dictIsRehashing(ht) ((ht)->rehashidx != -1)
A
antirez 已提交
122 123 124

/* API */
dict *dictCreate(dictType *type, void *privDataPtr);
A
antirez 已提交
125 126 127 128 129 130 131
int dictExpand(dict *d, unsigned long size);
int dictAdd(dict *d, void *key, void *val);
int dictReplace(dict *d, void *key, void *val);
int dictDelete(dict *d, const void *key);
int dictDeleteNoFree(dict *d, const void *key);
void dictRelease(dict *d);
dictEntry * dictFind(dict *d, const void *key);
132
void *dictFetchValue(dict *d, const void *key);
A
antirez 已提交
133 134
int dictResize(dict *d);
dictIterator *dictGetIterator(dict *d);
A
antirez 已提交
135 136
dictEntry *dictNext(dictIterator *iter);
void dictReleaseIterator(dictIterator *iter);
A
antirez 已提交
137 138
dictEntry *dictGetRandomKey(dict *d);
void dictPrintStats(dict *d);
A
antirez 已提交
139
unsigned int dictGenHashFunction(const unsigned char *buf, int len);
A
antirez 已提交
140
void dictEmpty(dict *d);
141 142
void dictEnableResize(void);
void dictDisableResize(void);
143
int dictRehash(dict *d, int n);
A
antirez 已提交
144
int dictRehashMilliseconds(dict *d, int ms);
A
antirez 已提交
145 146 147 148 149 150 151

/* Hash table types */
extern dictType dictTypeHeapStringCopyKey;
extern dictType dictTypeHeapStrings;
extern dictType dictTypeHeapStringCopyKeyValue;

#endif /* __DICT_H */