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Diffstat (limited to 'deps/hiredis/dict.c')
-rw-r--r-- | deps/hiredis/dict.c | 338 |
1 files changed, 0 insertions, 338 deletions
diff --git a/deps/hiredis/dict.c b/deps/hiredis/dict.c deleted file mode 100644 index e17a62546..000000000 --- a/deps/hiredis/dict.c +++ /dev/null @@ -1,338 +0,0 @@ -/* 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. - */ - -#include "fmacros.h" -#include <stdlib.h> -#include <assert.h> -#include <limits.h> -#include "dict.h" - -/* -------------------------- private prototypes ---------------------------- */ - -static int _dictExpandIfNeeded(dict *ht); -static unsigned long _dictNextPower(unsigned long size); -static int _dictKeyIndex(dict *ht, const void *key); -static int _dictInit(dict *ht, dictType *type, void *privDataPtr); - -/* -------------------------- hash functions -------------------------------- */ - -/* Generic hash function (a popular one from Bernstein). - * I tested a few and this was the best. */ -static unsigned int dictGenHashFunction(const unsigned char *buf, int len) { - unsigned int hash = 5381; - - while (len--) - hash = ((hash << 5) + hash) + (*buf++); /* hash * 33 + c */ - return hash; -} - -/* ----------------------------- API implementation ------------------------- */ - -/* Reset an hashtable already initialized with ht_init(). - * NOTE: This function should only called by ht_destroy(). */ -static void _dictReset(dict *ht) { - ht->table = NULL; - ht->size = 0; - ht->sizemask = 0; - ht->used = 0; -} - -/* Create a new hash table */ -static dict *dictCreate(dictType *type, void *privDataPtr) { - dict *ht = malloc(sizeof(*ht)); - _dictInit(ht,type,privDataPtr); - return ht; -} - -/* Initialize the hash table */ -static int _dictInit(dict *ht, dictType *type, void *privDataPtr) { - _dictReset(ht); - ht->type = type; - ht->privdata = privDataPtr; - return DICT_OK; -} - -/* Expand or create the hashtable */ -static int dictExpand(dict *ht, unsigned long size) { - dict n; /* the new hashtable */ - unsigned long realsize = _dictNextPower(size), i; - - /* the size is invalid if it is smaller than the number of - * elements already inside the hashtable */ - if (ht->used > size) - return DICT_ERR; - - _dictInit(&n, ht->type, ht->privdata); - n.size = realsize; - n.sizemask = realsize-1; - n.table = calloc(realsize,sizeof(dictEntry*)); - - /* Copy all the elements from the old to the new table: - * note that if the old hash table is empty ht->size is zero, - * so dictExpand just creates an hash table. */ - n.used = ht->used; - for (i = 0; i < ht->size && ht->used > 0; i++) { - dictEntry *he, *nextHe; - - if (ht->table[i] == NULL) continue; - - /* For each hash entry on this slot... */ - he = ht->table[i]; - while(he) { - unsigned int h; - - nextHe = he->next; - /* Get the new element index */ - h = dictHashKey(ht, he->key) & n.sizemask; - he->next = n.table[h]; - n.table[h] = he; - ht->used--; - /* Pass to the next element */ - he = nextHe; - } - } - assert(ht->used == 0); - free(ht->table); - - /* Remap the new hashtable in the old */ - *ht = n; - return DICT_OK; -} - -/* Add an element to the target hash table */ -static int dictAdd(dict *ht, void *key, void *val) { - int index; - dictEntry *entry; - - /* Get the index of the new element, or -1 if - * the element already exists. */ - if ((index = _dictKeyIndex(ht, key)) == -1) - return DICT_ERR; - - /* Allocates the memory and stores key */ - entry = malloc(sizeof(*entry)); - entry->next = ht->table[index]; - ht->table[index] = entry; - - /* Set the hash entry fields. */ - dictSetHashKey(ht, entry, key); - dictSetHashVal(ht, entry, val); - ht->used++; - return DICT_OK; -} - -/* Add an element, discarding the old if the key already exists. - * Return 1 if the key was added from scratch, 0 if there was already an - * element with such key and dictReplace() just performed a value update - * operation. */ -static int dictReplace(dict *ht, void *key, void *val) { - dictEntry *entry, auxentry; - - /* Try to add the element. If the key - * does not exists dictAdd will succeed. */ - if (dictAdd(ht, key, val) == DICT_OK) - return 1; - /* It already exists, get the entry */ - entry = dictFind(ht, key); - /* Free the old value and set the new one */ - /* Set the new value and free the old one. Note that it is important - * to do that in this order, as the value may just be exactly the same - * as the previous one. In this context, think to reference counting, - * you want to increment (set), and then decrement (free), and not the - * reverse. */ - auxentry = *entry; - dictSetHashVal(ht, entry, val); - dictFreeEntryVal(ht, &auxentry); - return 0; -} - -/* Search and remove an element */ -static int dictDelete(dict *ht, const void *key) { - unsigned int h; - dictEntry *de, *prevde; - - if (ht->size == 0) - return DICT_ERR; - h = dictHashKey(ht, key) & ht->sizemask; - de = ht->table[h]; - - prevde = NULL; - while(de) { - if (dictCompareHashKeys(ht,key,de->key)) { - /* Unlink the element from the list */ - if (prevde) - prevde->next = de->next; - else - ht->table[h] = de->next; - - dictFreeEntryKey(ht,de); - dictFreeEntryVal(ht,de); - free(de); - ht->used--; - return DICT_OK; - } - prevde = de; - de = de->next; - } - return DICT_ERR; /* not found */ -} - -/* Destroy an entire hash table */ -static int _dictClear(dict *ht) { - unsigned long i; - - /* Free all the elements */ - for (i = 0; i < ht->size && ht->used > 0; i++) { - dictEntry *he, *nextHe; - - if ((he = ht->table[i]) == NULL) continue; - while(he) { - nextHe = he->next; - dictFreeEntryKey(ht, he); - dictFreeEntryVal(ht, he); - free(he); - ht->used--; - he = nextHe; - } - } - /* Free the table and the allocated cache structure */ - free(ht->table); - /* Re-initialize the table */ - _dictReset(ht); - return DICT_OK; /* never fails */ -} - -/* Clear & Release the hash table */ -static void dictRelease(dict *ht) { - _dictClear(ht); - free(ht); -} - -static dictEntry *dictFind(dict *ht, const void *key) { - dictEntry *he; - unsigned int h; - - if (ht->size == 0) return NULL; - h = dictHashKey(ht, key) & ht->sizemask; - he = ht->table[h]; - while(he) { - if (dictCompareHashKeys(ht, key, he->key)) - return he; - he = he->next; - } - return NULL; -} - -static dictIterator *dictGetIterator(dict *ht) { - dictIterator *iter = malloc(sizeof(*iter)); - - iter->ht = ht; - iter->index = -1; - iter->entry = NULL; - iter->nextEntry = NULL; - return iter; -} - -static dictEntry *dictNext(dictIterator *iter) { - while (1) { - if (iter->entry == NULL) { - iter->index++; - if (iter->index >= - (signed)iter->ht->size) break; - iter->entry = iter->ht->table[iter->index]; - } else { - iter->entry = iter->nextEntry; - } - if (iter->entry) { - /* We need to save the 'next' here, the iterator user - * may delete the entry we are returning. */ - iter->nextEntry = iter->entry->next; - return iter->entry; - } - } - return NULL; -} - -static void dictReleaseIterator(dictIterator *iter) { - free(iter); -} - -/* ------------------------- private functions ------------------------------ */ - -/* Expand the hash table if needed */ -static int _dictExpandIfNeeded(dict *ht) { - /* If the hash table is empty expand it to the initial size, - * if the table is "full" dobule its size. */ - if (ht->size == 0) - return dictExpand(ht, DICT_HT_INITIAL_SIZE); - if (ht->used == ht->size) - return dictExpand(ht, ht->size*2); - return DICT_OK; -} - -/* Our hash table capability is a power of two */ -static unsigned long _dictNextPower(unsigned long size) { - unsigned long i = DICT_HT_INITIAL_SIZE; - - if (size >= LONG_MAX) return LONG_MAX; - while(1) { - if (i >= size) - return i; - i *= 2; - } -} - -/* Returns the index of a free slot that can be populated with - * an hash entry for the given 'key'. - * If the key already exists, -1 is returned. */ -static int _dictKeyIndex(dict *ht, const void *key) { - unsigned int h; - dictEntry *he; - - /* Expand the hashtable if needed */ - if (_dictExpandIfNeeded(ht) == DICT_ERR) - return -1; - /* Compute the key hash value */ - h = dictHashKey(ht, key) & ht->sizemask; - /* Search if this slot does not already contain the given key */ - he = ht->table[h]; - while(he) { - if (dictCompareHashKeys(ht, key, he->key)) - return -1; - he = he->next; - } - return h; -} - |