ha0storage.h File Reference

#include "univ.i"
#include "ha0storage.ic"

Include dependency graph for ha0storage.h:

This graph shows which files directly or indirectly include this file:

Go to the source code of this file.

Macros
#define	HA_STORAGE_DEFAULT_HEAP_BYTES   1024
#define	HA_STORAGE_DEFAULT_HASH_CELLS   4096
#define	ha_storage_put(storage, data, data_len)   ha_storage_put_memlim((storage), (data), (data_len), 0)
#define	ha_storage_put_str(storage, str)   ((const char*) ha_storage_put((storage), (str), strlen(str) + 1))
#define	ha_storage_put_str_memlim(storage, str, memlim)

Functions
UNIV_INLINE ha_storage_t *	ha_storage_create (ulint initial_heap_bytes, ulint initial_hash_cells)
UNIV_INTERN const void *	ha_storage_put_memlim (ha_storage_t *storage, const void *data, ulint data_len, ulint memlim)
UNIV_INLINE void	ha_storage_empty (ha_storage_t **storage)
UNIV_INLINE void	ha_storage_free (ha_storage_t *storage)
UNIV_INLINE ulint	ha_storage_get_size (const ha_storage_t *storage)

Detailed Description

Hash storage. Provides a data structure that stores chunks of data in its own storage, avoiding duplicates.

Created September 22, 2007 Vasil Dimov

Macro Definition Documentation

#define HA_STORAGE_DEFAULT_HASH_CELLS   4096

This value is used by default by ha_storage_create(). It is a

constant per ha_storage's lifetime.

#define HA_STORAGE_DEFAULT_HEAP_BYTES   1024

This value is used by default by ha_storage_create(). More memory

is allocated later when/if it is needed.

#define ha_storage_put	(		storage,
			data,
			data_len
	)		ha_storage_put_memlim((storage), (data), (data_len), 0)

Same as ha_storage_put_memlim() but without memory limit.

Parameters

storage	in/out: hash storage
data	in: data to store
data_len	in: data length

Returns

pointer to the copy of the string

#define ha_storage_put_str	(		storage,
			str
	)		((const char*) ha_storage_put((storage), (str), strlen(str) + 1))

Copies string into the storage and returns a pointer to the copy. If the same string is already present, then pointer to it is returned. Strings are considered to be equal if strcmp(str1, str2) == 0.

Parameters

storage	in/out: hash storage
str	in: string to put

Returns

pointer to the copy of the string

#define ha_storage_put_str_memlim	(		storage,
			str,
			memlim
	)

Value:

((const char*) ha_storage_put_memlim((storage), (str),  \
                                             strlen(str) + 1, (memlim)))

Copies string into the storage and returns a pointer to the copy obeying a memory limit. If the same string is already present, then pointer to it is returned. Strings are considered to be equal if strcmp(str1, str2) == 0.

Parameters

storage	in/out: hash storage
str	in: string to put
memlim	in: memory limit to obey

Returns

pointer to the copy of the string

Function Documentation

UNIV_INLINE ha_storage_t* ha_storage_create	(	ulint	initial_heap_bytes,
		ulint	initial_hash_cells
	)

Creates a hash storage. If any of the parameters is 0, then a default value is used.

Returns

own: hash storage in: initial number of cells in the hash table

Creates a hash storage. If any of the parameters is 0, then a default value is used.

Returns

own: hash storage

Parameters

initial_heap_bytes	in: initial heap's size
initial_hash_cells	in: initial number of cells in the hash table

UNIV_INLINE void ha_storage_empty

(

ha_storage_t **

storage

)

Empties a hash storage, freeing memory occupied by data chunks. This invalidates any pointers previously returned by ha_storage_put(). The hash storage is not invalidated itself and can be used again. in/out: hash storage

Empties a hash storage, freeing memory occupied by data chunks. This invalidates any pointers previously returned by ha_storage_put(). The hash storage is not invalidated itself and can be used again.

Parameters

storage

in/out: hash storage

UNIV_INLINE void ha_storage_free

(

ha_storage_t *

storage

)

Frees a hash storage and everything it contains, it cannot be used after this call. This invalidates any pointers previously returned by ha_storage_put(). in, own: hash storage

Frees a hash storage and everything it contains, it cannot be used after this call. This invalidates any pointers previously returned by ha_storage_put().

Parameters

storage

in, own: hash storage

UNIV_INLINE ulint ha_storage_get_size

(

const ha_storage_t *

storage

)

Gets the size of the memory used by a storage.

Returns

bytes used in: hash storage

Gets the size of the memory used by a storage.

Returns

bytes used

Parameters

storage

in: hash storage

UNIV_INTERN const void* ha_storage_put_memlim	(	ha_storage_t *	storage,
		const void *	data,
		ulint	data_len,
		ulint	memlim
	)

Copies data into the storage and returns a pointer to the copy. If the same data chunk is already present, then pointer to it is returned. Data chunks are considered to be equal if len1 == len2 and memcmp(data1, data2, len1) == 0. If "data" is not present (and thus data_len bytes need to be allocated) and the size of storage is going to become more than "memlim" then "data" is not added and NULL is returned. To disable this behavior "memlim" can be set to 0, which stands for "no limit".

Returns

pointer to the copy in: memory limit to obey

Parameters

storage	in/out: hash storage
data	in: data to store
data_len	in: data length