gecko-dev/js/ref/prhash.h

132 строки
4.8 KiB
C

/* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
*
* The contents of this file are subject to the Netscape Public License
* Version 1.0 (the "NPL"); you may not use this file except in
* compliance with the NPL. You may obtain a copy of the NPL at
* http://www.mozilla.org/NPL/
*
* Software distributed under the NPL is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the NPL
* for the specific language governing rights and limitations under the
* NPL.
*
* The Initial Developer of this code under the NPL is Netscape
* Communications Corporation. Portions created by Netscape are
* Copyright (C) 1998 Netscape Communications Corporation. All Rights
* Reserved.
*/
#ifndef prhash_h___
#define prhash_h___
/*
* API to portable hash table code.
*/
#include <stddef.h>
#include <stdio.h>
#include "prtypes.h"
PR_BEGIN_EXTERN_C
typedef uint32 prhashcode;
#define PR_HASH_BITS 32
#define PR_GOLDEN_RATIO 0x9E3779B9U
typedef prhashcode (*PRHashFunction)(const void *key);
typedef intN (*PRHashComparator)(const void *v1, const void *v2);
typedef intN (*PRHashEnumerator)(PRHashEntry *he, intN i, void *arg);
/* Flag bits in PRHashEnumerator's return value */
#define HT_ENUMERATE_NEXT 0 /* continue enumerating entries */
#define HT_ENUMERATE_STOP 1 /* stop enumerating entries */
#define HT_ENUMERATE_REMOVE 2 /* remove and free the current entry */
#define HT_ENUMERATE_UNHASH 4 /* just unhash the current entry */
typedef struct PRHashAllocOps {
void * (*allocTable)(void *pool, size_t size);
void (*freeTable)(void *pool, void *item);
PRHashEntry * (*allocEntry)(void *pool, const void *key);
void (*freeEntry)(void *pool, PRHashEntry *he, uintN flag);
} PRHashAllocOps;
#define HT_FREE_VALUE 0 /* just free the entry's value */
#define HT_FREE_ENTRY 1 /* free value and entire entry */
struct PRHashEntry {
PRHashEntry *next; /* hash chain linkage */
prhashcode keyHash; /* key hash function result */
const void *key; /* ptr to opaque key */
void *value; /* ptr to opaque value */
};
struct PRHashTable {
PRHashEntry **buckets; /* vector of hash buckets */
uint32 nentries; /* number of entries in table */
uint32 shift; /* multiplicative hash shift */
PRHashFunction keyHash; /* key hash function */
PRHashComparator keyCompare; /* key comparison function */
PRHashComparator valueCompare; /* value comparison function */
PRHashAllocOps *allocOps; /* allocation operations */
void *allocPriv; /* allocation private data */
#ifdef HASHMETER
uint32 nlookups; /* total number of lookups */
uint32 nsteps; /* number of hash chains traversed */
uint32 ngrows; /* number of table expansions */
uint32 nshrinks; /* number of table contractions */
#endif
};
/*
* Create a new hash table.
* If allocOps is null, use default allocator ops built on top of malloc().
*/
extern PR_PUBLIC_API(PRHashTable *)
PR_NewHashTable(uint32 n, PRHashFunction keyHash,
PRHashComparator keyCompare, PRHashComparator valueCompare,
PRHashAllocOps *allocOps, void *allocPriv);
extern PR_PUBLIC_API(void)
PR_HashTableDestroy(PRHashTable *ht);
/* Low level access methods */
extern PR_PUBLIC_API(PRHashEntry **)
PR_HashTableRawLookup(PRHashTable *ht, prhashcode keyHash, const void *key);
extern PR_PUBLIC_API(PRHashEntry *)
PR_HashTableRawAdd(PRHashTable *ht, PRHashEntry **hep, prhashcode keyHash,
const void *key, void *value);
extern PR_PUBLIC_API(void)
PR_HashTableRawRemove(PRHashTable *ht, PRHashEntry **hep, PRHashEntry *he);
/* Higher level access methods */
extern PR_PUBLIC_API(PRHashEntry *)
PR_HashTableAdd(PRHashTable *ht, const void *key, void *value);
extern PR_PUBLIC_API(PRBool)
PR_HashTableRemove(PRHashTable *ht, const void *key);
extern PR_PUBLIC_API(intN)
PR_HashTableEnumerateEntries(PRHashTable *ht, PRHashEnumerator f, void *arg);
extern PR_PUBLIC_API(void *)
PR_HashTableLookup(PRHashTable *ht, const void *key);
extern PR_PUBLIC_API(intN)
PR_HashTableDump(PRHashTable *ht, PRHashEnumerator dump, FILE *fp);
/* General-purpose C string hash function. */
extern PR_PUBLIC_API(prhashcode)
PR_HashString(const void *key);
/* Compare strings using strcmp(), return true if equal. */
extern PR_PUBLIC_API(int)
PR_CompareStrings(const void *v1, const void *v2);
/* Stub function just returns v1 == v2 */
PR_PUBLIC_API(intN)
PR_CompareValues(const void *v1, const void *v2);
PR_END_EXTERN_C
#endif /* prhash_h___ */