hiredis/dict.h

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/* Hash table 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... :)
*
* Copyright (c) 2006-2010, Salvatore Sanfilippo <antirez at gmail dot com>
* 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;
typedef struct dict {
dictEntry **table;
dictType *type;
unsigned long size;
unsigned long sizemask;
unsigned long used;
void *privdata;
} dict;
typedef struct dictIterator {
dict *ht;
int index;
dictEntry *entry, *nextEntry;
} dictIterator;
/* This is the initial size of every hash table */
#define DICT_HT_INITIAL_SIZE 4
/* ------------------------------- Macros ------------------------------------*/
#define dictFreeEntryVal(ht, entry) \
if ((ht)->type->valDestructor) \
(ht)->type->valDestructor((ht)->privdata, (entry)->val)
#define dictSetHashVal(ht, entry, _val_) do { \
if ((ht)->type->valDup) \
entry->val = (ht)->type->valDup((ht)->privdata, _val_); \
else \
entry->val = (_val_); \
} while(0)
#define dictFreeEntryKey(ht, entry) \
if ((ht)->type->keyDestructor) \
(ht)->type->keyDestructor((ht)->privdata, (entry)->key)
#define dictSetHashKey(ht, entry, _key_) do { \
if ((ht)->type->keyDup) \
entry->key = (ht)->type->keyDup((ht)->privdata, _key_); \
else \
entry->key = (_key_); \
} while(0)
#define dictCompareHashKeys(ht, key1, key2) \
(((ht)->type->keyCompare) ? \
(ht)->type->keyCompare((ht)->privdata, key1, key2) : \
(key1) == (key2))
#define dictHashKey(ht, key) (ht)->type->hashFunction(key)
#define dictGetEntryKey(he) ((he)->key)
#define dictGetEntryVal(he) ((he)->val)
#define dictSlots(ht) ((ht)->size)
#define dictSize(ht) ((ht)->used)
/* API */
static unsigned int dictGenHashFunction(const unsigned char *buf, int len);
static dict *dictCreate(dictType *type, void *privDataPtr);
static int dictExpand(dict *ht, unsigned long size);
static int dictAdd(dict *ht, void *key, void *val);
static int dictReplace(dict *ht, void *key, void *val);
static int dictDelete(dict *ht, const void *key);
static void dictRelease(dict *ht);
static dictEntry * dictFind(dict *ht, const void *key);
static dictIterator *dictGetIterator(dict *ht);
static dictEntry *dictNext(dictIterator *iter);
static void dictReleaseIterator(dictIterator *iter);
#endif /* __DICT_H */