cgi/hash.h File Reference

hash functions. More...

Defines
#define	HASH_TABLE_SIZE   65535
	Hash table size.
Typedefs
typedef unsigned int(*	t_hash_fn )(void *)
	Hash function type.
typedef int(*	t_hash_key_compare_fn )(void *, void *)
	Keys comparison function type.
typedef void *(*	t_hash_key_copy_fn )(void *)
	Key copy function type.
typedef void(*	t_hash_key_free_fn )(void *)
	Free key function type.
typedef struct s_hash	t_hash
	Hash type.
Functions
void *	hash_find (t_hash *, void *)
	Find hash value with given key.
void	hash_add (t_hash *, void *, void *)
	Adds new value with given key.
void	hash_del (t_hash *, void *)
	Deletes element with given key.
t_hash *	hash_create (t_hash_key_compare_fn, t_hash_key_copy_fn, t_hash_key_free_fn, t_hash_fn)
	Create hash using given functions for keys manipulations.
t_hash *	hash_create_strkey ()
	Create hash with char* keys.
void	hash_free (t_hash *)
	Frees hash and releases occupied memory.

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Detailed Description

hash functions.

Author:

Vladimir Pavluk, 2006-2007

Hash is a data structure to speed up data searching based on keys. This file contains functions to create and handle hash structures.

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Define Documentation

#define HASH_TABLE_SIZE   65535

Hash table size.

Size of a virtual hash table. The bigger is it, the more memory it consumes, but works faster.

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Typedef Documentation

typedef struct s_hash t_hash

Hash type.

Contains hash structure.

typedef unsigned int(* t_hash_fn)(void *)

Hash function type.

Function converting key to integer in range 0 to HASH_TABLE_SIZE.

typedef int(* t_hash_key_compare_fn)(void *, void *)

Keys comparison function type.

Function returning -1 0 or 1 depending on keys comparison.

typedef void*(* t_hash_key_copy_fn)(void *)

Key copy function type.

Function returning a copy of key.

typedef void(* t_hash_key_free_fn)(void *)

Free key function type.

Function freeing passed key.

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Function Documentation

void hash_add	(	t_hash *	hash,
		void *	key,
		void *	data
	)

Adds new value with given key.

Adds hash element with given key and value.

Attention:

WARNING: its your responsibility to ensure the hash is valid.

Parameters:

	hash	hash to add to.
	key	key to add.
	data	element data.

See also:

hash_create(t_hash_key_compare_fn, t_hash_key_copy_fn, t_hash_key_free_fn, t_hash_fn)

hash_find(t_hash *, void *)

hash_del(t_hash *, void *)

t_hash* hash_create	(	t_hash_key_compare_fn	cmp,
		t_hash_key_copy_fn	cpy,
		t_hash_key_free_fn	kfree,
		t_hash_fn	hash_fn
	)

Create hash using given functions for keys manipulations.

Creates hash using given functions for keys manipulations.

Parameters:

	cmp	comparison function.
	cpy	function for copying keys.
	kfree	function for releasing memory occupied by key.
	hash_fn	hash function.

Returns:

pointer to created hash (t_hash*).

See also:

hash_create_strkey()

hash_free(t_hash *)

t_hash* hash_create_strkey

(

)

Create hash with char* keys.

Automatically creates hash using existing functions for char* keys manipulations.

Returns:

pointer to created hash (t_hash*).

See also:

hash_create(t_hash_key_compare_fn, t_hash_key_copy_fn, t_hash_key_free_fn, t_hash_fn)

hash_free(t_hash *)

void hash_del	(	t_hash *	hash,
		void *	key
	)

Deletes element with given key.

Deletes hash element with given key.

Attention:

WARNING: its your responsibility to ensure the hash is valid.

Parameters:

	hash	hash to delete from.
	key	key to delete.

See also:

hash_create(t_hash_key_compare_fn, t_hash_key_copy_fn, t_hash_key_free_fn, t_hash_fn)

hash_add(t_hash *, void *, void *)

hash_find(t_hash *, void *)

void* hash_find	(	t_hash *	hash,
		void *	key
	)

Find hash value with given key.

Finds hash element with given key and returns its value.

Attention:

WARNING: its your responsibility to ensure the hash is valid.

Parameters:

	hash	hash to search in.
	key	key for which to search.

Returns:

pointer to found element, or null if not found.

See also:

hash_create(t_hash_key_compare_fn, t_hash_key_copy_fn, t_hash_key_free_fn, t_hash_fn)

hash_add(t_hash *, void *, void *)

hash_del(t_hash *, void *)

void hash_free

(

t_hash *

hash

)

Frees hash and releases occupied memory.

Releases memory occupied by the hash. Deletes all hash elements.

Attention:

WARNING: its your responsibility to ensure the hash is valid.

WARNING: if you don't keep your data pointers anywhere else, you will lose all the data,

along with memory it occupies.

Parameters:

hash

hash to add to.

See also:

hash_create(t_hash_key_compare_fn, t_hash_key_copy_fn, t_hash_key_free_fn, t_hash_fn)

hash_create_strkey()