michael@0: /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #ifndef plhash_h___
michael@0: #define plhash_h___
michael@0: /*
michael@0:  * API to portable hash table code.
michael@0:  */
michael@0: #include <stdio.h>
michael@0: #include "prtypes.h"
michael@0: 
michael@0: PR_BEGIN_EXTERN_C
michael@0: 
michael@0: typedef struct PLHashEntry  PLHashEntry;
michael@0: typedef struct PLHashTable  PLHashTable;
michael@0: typedef PRUint32 PLHashNumber;
michael@0: #define PL_HASH_BITS 32  /* Number of bits in PLHashNumber */
michael@0: typedef PLHashNumber (PR_CALLBACK *PLHashFunction)(const void *key);
michael@0: typedef PRIntn (PR_CALLBACK *PLHashComparator)(const void *v1, const void *v2);
michael@0: 
michael@0: typedef PRIntn (PR_CALLBACK *PLHashEnumerator)(PLHashEntry *he, PRIntn i, void *arg);
michael@0: 
michael@0: /* Flag bits in PLHashEnumerator's return value */
michael@0: #define HT_ENUMERATE_NEXT       0       /* continue enumerating entries */
michael@0: #define HT_ENUMERATE_STOP       1       /* stop enumerating entries */
michael@0: #define HT_ENUMERATE_REMOVE     2       /* remove and free the current entry */
michael@0: #define HT_ENUMERATE_UNHASH     4       /* just unhash the current entry */
michael@0: 
michael@0: typedef struct PLHashAllocOps {
michael@0:     void *              (PR_CALLBACK *allocTable)(void *pool, PRSize size);
michael@0:     void                (PR_CALLBACK *freeTable)(void *pool, void *item);
michael@0:     PLHashEntry *       (PR_CALLBACK *allocEntry)(void *pool, const void *key);
michael@0:     void                (PR_CALLBACK *freeEntry)(void *pool, PLHashEntry *he, PRUintn flag);
michael@0: } PLHashAllocOps;
michael@0: 
michael@0: #define HT_FREE_VALUE   0               /* just free the entry's value */
michael@0: #define HT_FREE_ENTRY   1               /* free value and entire entry */
michael@0: 
michael@0: struct PLHashEntry {
michael@0:     PLHashEntry         *next;          /* hash chain linkage */
michael@0:     PLHashNumber        keyHash;        /* key hash function result */
michael@0:     const void          *key;           /* ptr to opaque key */
michael@0:     void                *value;         /* ptr to opaque value */
michael@0: };
michael@0: 
michael@0: struct PLHashTable {
michael@0:     PLHashEntry         **buckets;      /* vector of hash buckets */
michael@0:     PRUint32              nentries;       /* number of entries in table */
michael@0:     PRUint32              shift;          /* multiplicative hash shift */
michael@0:     PLHashFunction      keyHash;        /* key hash function */
michael@0:     PLHashComparator    keyCompare;     /* key comparison function */
michael@0:     PLHashComparator    valueCompare;   /* value comparison function */
michael@0:     const PLHashAllocOps *allocOps;     /* allocation operations */
michael@0:     void                *allocPriv;     /* allocation private data */
michael@0: #ifdef HASHMETER
michael@0:     PRUint32              nlookups;       /* total number of lookups */
michael@0:     PRUint32              nsteps;         /* number of hash chains traversed */
michael@0:     PRUint32              ngrows;         /* number of table expansions */
michael@0:     PRUint32              nshrinks;       /* number of table contractions */
michael@0: #endif
michael@0: };
michael@0: 
michael@0: /*
michael@0:  * Create a new hash table.
michael@0:  * If allocOps is null, use default allocator ops built on top of malloc().
michael@0:  */
michael@0: PR_EXTERN(PLHashTable *)
michael@0: PL_NewHashTable(PRUint32 numBuckets, PLHashFunction keyHash,
michael@0:                 PLHashComparator keyCompare, PLHashComparator valueCompare,
michael@0:                 const PLHashAllocOps *allocOps, void *allocPriv);
michael@0: 
michael@0: PR_EXTERN(void)
michael@0: PL_HashTableDestroy(PLHashTable *ht);
michael@0: 
michael@0: /* Higher level access methods */
michael@0: PR_EXTERN(PLHashEntry *)
michael@0: PL_HashTableAdd(PLHashTable *ht, const void *key, void *value);
michael@0: 
michael@0: PR_EXTERN(PRBool)
michael@0: PL_HashTableRemove(PLHashTable *ht, const void *key);
michael@0: 
michael@0: PR_EXTERN(void *)
michael@0: PL_HashTableLookup(PLHashTable *ht, const void *key);
michael@0: 
michael@0: PR_EXTERN(void *)
michael@0: PL_HashTableLookupConst(PLHashTable *ht, const void *key);
michael@0: 
michael@0: PR_EXTERN(PRIntn)
michael@0: PL_HashTableEnumerateEntries(PLHashTable *ht, PLHashEnumerator f, void *arg);
michael@0: 
michael@0: /* General-purpose C string hash function. */
michael@0: PR_EXTERN(PLHashNumber)
michael@0: PL_HashString(const void *key);
michael@0: 
michael@0: /* Compare strings using strcmp(), return true if equal. */
michael@0: PR_EXTERN(PRIntn)
michael@0: PL_CompareStrings(const void *v1, const void *v2);
michael@0: 
michael@0: /* Stub function just returns v1 == v2 */
michael@0: PR_EXTERN(PRIntn)
michael@0: PL_CompareValues(const void *v1, const void *v2);
michael@0: 
michael@0: /* Low level access methods */
michael@0: PR_EXTERN(PLHashEntry **)
michael@0: PL_HashTableRawLookup(PLHashTable *ht, PLHashNumber keyHash, const void *key);
michael@0: 
michael@0: PR_EXTERN(PLHashEntry **)
michael@0: PL_HashTableRawLookupConst(PLHashTable *ht, PLHashNumber keyHash,
michael@0:                            const void *key);
michael@0: 
michael@0: PR_EXTERN(PLHashEntry *)
michael@0: PL_HashTableRawAdd(PLHashTable *ht, PLHashEntry **hep, PLHashNumber keyHash,
michael@0:                    const void *key, void *value);
michael@0: 
michael@0: PR_EXTERN(void)
michael@0: PL_HashTableRawRemove(PLHashTable *ht, PLHashEntry **hep, PLHashEntry *he);
michael@0: 
michael@0: /* This can be trivially implemented using PL_HashTableEnumerateEntries. */
michael@0: PR_EXTERN(PRIntn)
michael@0: PL_HashTableDump(PLHashTable *ht, PLHashEnumerator dump, FILE *fp);
michael@0: 
michael@0: PR_END_EXTERN_C
michael@0: 
michael@0: #endif /* plhash_h___ */