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+/* 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... :)
+ *
+ * Copyright (c) 2006-2012, 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
+
+#include "mt19937-64.h"
+#include <limits.h>
+#include <stdint.h>
+#include <stdlib.h>
+
+#define DICT_OK 0
+#define DICT_ERR 1
+
+typedef struct dictEntry {
+ void *key;
+ union {
+ void *val;
+ uint64_t u64;
+ int64_t s64;
+ double d;
+ } v;
+ struct dictEntry *next; /* Next entry in the same hash bucket. */
+ void *metadata[]; /* An arbitrary number of bytes (starting at a
+ * pointer-aligned address) of size as returned
+ * by dictType's dictEntryMetadataBytes(). */
+} dictEntry;
+
+typedef struct dict dict;
+
+typedef struct dictType {
+ uint64_t (*hashFunction)(const void *key);
+ void *(*keyDup)(dict *d, const void *key);
+ void *(*valDup)(dict *d, const void *obj);
+ int (*keyCompare)(dict *d, const void *key1, const void *key2);
+ void (*keyDestructor)(dict *d, void *key);
+ void (*valDestructor)(dict *d, void *obj);
+ int (*expandAllowed)(size_t moreMem, double usedRatio);
+ /* Allow a dictEntry to carry extra caller-defined metadata. The
+ * extra memory is initialized to 0 when a dictEntry is allocated. */
+ size_t (*dictEntryMetadataBytes)(dict *d);
+} dictType;
+
+#define DICTHT_SIZE(exp) ((exp) == -1 ? 0 : (unsigned long)1<<(exp))
+#define DICTHT_SIZE_MASK(exp) ((exp) == -1 ? 0 : (DICTHT_SIZE(exp))-1)
+
+struct dict {
+ dictType *type;
+
+ dictEntry **ht_table[2];
+ unsigned long ht_used[2];
+
+ long rehashidx; /* rehashing not in progress if rehashidx == -1 */
+
+ /* Keep small vars at end for optimal (minimal) struct padding */
+ int16_t pauserehash; /* If >0 rehashing is paused (<0 indicates coding error) */
+ signed char ht_size_exp[2]; /* exponent of size. (size = 1<<exp) */
+};
+
+/* If safe is set to 1 this is a safe iterator, that means, you can call
+ * dictAdd, dictFind, and other functions against the dictionary even while
+ * iterating. Otherwise it is a non safe iterator, and only dictNext()
+ * should be called while iterating. */
+typedef struct dictIterator {
+ dict *d;
+ long index;
+ int table, safe;
+ dictEntry *entry, *nextEntry;
+ /* unsafe iterator fingerprint for misuse detection. */
+ unsigned long long fingerprint;
+} dictIterator;
+
+typedef void (dictScanFunction)(void *privdata, const dictEntry *de);
+typedef void (dictScanBucketFunction)(dict *d, dictEntry **bucketref);
+
+/* This is the initial size of every hash table */
+#define DICT_HT_INITIAL_EXP 2
+#define DICT_HT_INITIAL_SIZE (1<<(DICT_HT_INITIAL_EXP))
+
+/* ------------------------------- Macros ------------------------------------*/
+#define dictFreeVal(d, entry) \
+ if ((d)->type->valDestructor) \
+ (d)->type->valDestructor((d), (entry)->v.val)
+
+#define dictSetVal(d, entry, _val_) do { \
+ if ((d)->type->valDup) \
+ (entry)->v.val = (d)->type->valDup((d), _val_); \
+ else \
+ (entry)->v.val = (_val_); \
+} while(0)
+
+#define dictSetSignedIntegerVal(entry, _val_) \
+ do { (entry)->v.s64 = _val_; } while(0)
+
+#define dictSetUnsignedIntegerVal(entry, _val_) \
+ do { (entry)->v.u64 = _val_; } while(0)
+
+#define dictSetDoubleVal(entry, _val_) \
+ do { (entry)->v.d = _val_; } while(0)
+
+#define dictFreeKey(d, entry) \
+ if ((d)->type->keyDestructor) \
+ (d)->type->keyDestructor((d), (entry)->key)
+
+#define dictSetKey(d, entry, _key_) do { \
+ if ((d)->type->keyDup) \
+ (entry)->key = (d)->type->keyDup((d), _key_); \
+ else \
+ (entry)->key = (_key_); \
+} while(0)
+
+#define dictCompareKeys(d, key1, key2) \
+ (((d)->type->keyCompare) ? \
+ (d)->type->keyCompare((d), key1, key2) : \
+ (key1) == (key2))
+
+#define dictMetadata(entry) (&(entry)->metadata)
+#define dictMetadataSize(d) ((d)->type->dictEntryMetadataBytes \
+ ? (d)->type->dictEntryMetadataBytes(d) : 0)
+
+#define dictHashKey(d, key) (d)->type->hashFunction(key)
+#define dictGetKey(he) ((he)->key)
+#define dictGetVal(he) ((he)->v.val)
+#define dictGetSignedIntegerVal(he) ((he)->v.s64)
+#define dictGetUnsignedIntegerVal(he) ((he)->v.u64)
+#define dictGetDoubleVal(he) ((he)->v.d)
+#define dictSlots(d) (DICTHT_SIZE((d)->ht_size_exp[0])+DICTHT_SIZE((d)->ht_size_exp[1]))
+#define dictSize(d) ((d)->ht_used[0]+(d)->ht_used[1])
+#define dictIsRehashing(d) ((d)->rehashidx != -1)
+#define dictPauseRehashing(d) (d)->pauserehash++
+#define dictResumeRehashing(d) (d)->pauserehash--
+
+/* If our unsigned long type can store a 64 bit number, use a 64 bit PRNG. */
+#if ULONG_MAX >= 0xffffffffffffffff
+#define randomULong() ((unsigned long) genrand64_int64())
+#else
+#define randomULong() random()
+#endif
+
+typedef enum {
+ DICT_RESIZE_ENABLE,
+ DICT_RESIZE_AVOID,
+ DICT_RESIZE_FORBID,
+} dictResizeEnable;
+
+/* API */
+dict *dictCreate(dictType *type);
+int dictExpand(dict *d, unsigned long size);
+int dictTryExpand(dict *d, unsigned long size);
+int dictAdd(dict *d, void *key, void *val);
+dictEntry *dictAddRaw(dict *d, void *key, dictEntry **existing);
+dictEntry *dictAddOrFind(dict *d, void *key);
+int dictReplace(dict *d, void *key, void *val);
+int dictDelete(dict *d, const void *key);
+dictEntry *dictUnlink(dict *d, const void *key);
+void dictFreeUnlinkedEntry(dict *d, dictEntry *he);
+void dictRelease(dict *d);
+dictEntry * dictFind(dict *d, const void *key);
+void *dictFetchValue(dict *d, const void *key);
+int dictResize(dict *d);
+dictIterator *dictGetIterator(dict *d);
+dictIterator *dictGetSafeIterator(dict *d);
+dictEntry *dictNext(dictIterator *iter);
+void dictReleaseIterator(dictIterator *iter);
+dictEntry *dictGetRandomKey(dict *d);
+dictEntry *dictGetFairRandomKey(dict *d);
+unsigned int dictGetSomeKeys(dict *d, dictEntry **des, unsigned int count);
+void dictGetStats(char *buf, size_t bufsize, dict *d);
+uint64_t dictGenHashFunction(const void *key, size_t len);
+uint64_t dictGenCaseHashFunction(const unsigned char *buf, size_t len);
+void dictEmpty(dict *d, void(callback)(dict*));
+void dictSetResizeEnabled(dictResizeEnable enable);
+int dictRehash(dict *d, int n);
+int dictRehashMilliseconds(dict *d, int ms);
+void dictSetHashFunctionSeed(uint8_t *seed);
+uint8_t *dictGetHashFunctionSeed(void);
+unsigned long dictScan(dict *d, unsigned long v, dictScanFunction *fn, dictScanBucketFunction *bucketfn, void *privdata);
+uint64_t dictGetHash(dict *d, const void *key);
+dictEntry **dictFindEntryRefByPtrAndHash(dict *d, const void *oldptr, uint64_t hash);
+
+#ifdef REDIS_TEST
+int dictTest(int argc, char *argv[], int flags);
+#endif
+
+#endif /* __DICT_H */