Hash storage. More...

#include "ha0storage.h"
#include "ha_prototypes.h"
#include "hash0hash.h"
#include "mem0mem.h"
#include "ut0rnd.h"

Macros
#define	IS_FOUND node->data_len == data_len &&memcmp(node->data, data, data_len) == 0

Functions
static const void *	ha_storage_get (ha_storage_t storage, const void data, ulint data_len)
	Retrieves a data from a storage. More...

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. More...

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

◆ IS_FOUND

#define IS_FOUND node->data_len == data_len &&memcmp(node->data, data, data_len) == 0

Function Documentation

◆ ha_storage_get()

static const void * ha_storage_get	(	ha_storage_t *	storage,
		const void *	data,
		ulint	data_len
	)

static

Retrieves a data from a storage.

If it is present, a pointer to the stored copy of data is returned, otherwise NULL is returned.

Parameters

storage	in: hash storage
data	in: data to check for
data_len	in: data length

◆ ha_storage_put_memlim()

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".