[thirdparty/squid.git] / include / hash.h

/*
 * $Id: hash.h,v 1.4 2000/10/31 23:48:08 wessels Exp $
 */

typedef void HASHFREE(void *);
typedef int HASHCMP(const void *, const void *);
typedef unsigned int HASHHASH(const void *, unsigned int);
typedef struct _hash_link hash_link;
typedef struct _hash_table hash_table;

struct _hash_link {
    void *key;
    hash_link *next;
};

struct _hash_table {
    hash_link **buckets;
    HASHCMP *cmp;
    HASHHASH *hash;
    unsigned int size;
    unsigned int current_slot;
    hash_link *next;
    int count;
};

extern hash_table *hash_create(HASHCMP *, int, HASHHASH *);
extern void hash_join(hash_table *, hash_link *);
extern void hash_remove_link(hash_table *, hash_link *);
extern int hashPrime(int n);
extern void *hash_lookup(hash_table *, const void *);
extern void hash_first(hash_table *);
extern void *hash_next(hash_table *);
extern void hash_last(hash_table *);
extern hash_link *hash_get_bucket(hash_table *, unsigned int);
extern void hashFreeMemory(hash_table *);
extern void hashFreeItems(hash_table *, HASHFREE *);
extern HASHHASH hash_string;
extern HASHHASH hash4;
extern const char *hashKeyStr(hash_link *);

/*
 *  Here are some good prime number choices.  It's important not to
 *  choose a prime number that is too close to exact powers of 2.
 *
 *  HASH_SIZE 103               // prime number < 128
 *  HASH_SIZE 229               // prime number < 256
 *  HASH_SIZE 467               // prime number < 512
 *  HASH_SIZE 977               // prime number < 1024
 *  HASH_SIZE 1979              // prime number < 2048
 *  HASH_SIZE 4019              // prime number < 4096
 *  HASH_SIZE 6037              // prime number < 6144
 *  HASH_SIZE 7951              // prime number < 8192
 *  HASH_SIZE 12149             // prime number < 12288
 *  HASH_SIZE 16231             // prime number < 16384
 *  HASH_SIZE 33493             // prime number < 32768
 *  HASH_SIZE 65357             // prime number < 65536
 */
#define  DEFAULT_HASH_SIZE 7951	/* prime number < 8192 */
Commit	Line	Data
0e2cd867	1	/*
186477c1	2	* $Id: hash.h,v 1.4 2000/10/31 23:48:08 wessels Exp $
0e2cd867	3	*/
0e2cd867	4
f52a7d75	5	typedef void HASHFREE(void *);
	6	typedef int HASHCMP(const void , const void );
	7	typedef unsigned int HASHHASH(const void *, unsigned int);
	8	typedef struct _hash_link hash_link;
	9	typedef struct _hash_table hash_table;
	10
	11	struct _hash_link {
186477c1	12	void *key;
f52a7d75	13	hash_link *next;
	14	};
	15
	16	struct _hash_table {
	17	hash_link **buckets;
	18	HASHCMP *cmp;
	19	HASHHASH *hash;
	20	unsigned int size;
	21	unsigned int current_slot;
	22	hash_link *next;
	23	int count;
	24	};
	25
	26	extern hash_table hash_create(HASHCMP , int, HASHHASH *);
	27	extern void hash_join(hash_table , hash_link );
	28	extern void hash_remove_link(hash_table , hash_link );
	29	extern int hashPrime(int n);
	30	extern void hash_lookup(hash_table , const void *);
	31	extern void hash_first(hash_table *);
	32	extern void hash_next(hash_table );
2c4f7ab2	33	extern void hash_last(hash_table *);
f52a7d75	34	extern hash_link hash_get_bucket(hash_table , unsigned int);
	35	extern void hashFreeMemory(hash_table *);
	36	extern void hashFreeItems(hash_table , HASHFREE );
	37	extern HASHHASH hash_string;
	38	extern HASHHASH hash4;
186477c1	39	extern const char hashKeyStr(hash_link );
f52a7d75	40
	41	/*
	42	* Here are some good prime number choices. It's important not to
	43	* choose a prime number that is too close to exact powers of 2.
	44	*
	45	* HASH_SIZE 103 // prime number < 128
	46	* HASH_SIZE 229 // prime number < 256
	47	* HASH_SIZE 467 // prime number < 512
	48	* HASH_SIZE 977 // prime number < 1024
	49	* HASH_SIZE 1979 // prime number < 2048
	50	* HASH_SIZE 4019 // prime number < 4096
	51	* HASH_SIZE 6037 // prime number < 6144
	52	* HASH_SIZE 7951 // prime number < 8192
	53	* HASH_SIZE 12149 // prime number < 12288
	54	* HASH_SIZE 16231 // prime number < 16384
	55	* HASH_SIZE 33493 // prime number < 32768
	56	* HASH_SIZE 65357 // prime number < 65536
	57	*/
186477c1	58	#define DEFAULT_HASH_SIZE 7951 /* prime number < 8192 */