The Miscellaneous Group contains the API for routines that don't clearly fit into any of the other module API groups. More...

Functions
int	mdbm_get_errno (MDBM *db)
	Returns the value of internally saved errno. More...

int	mdbm_get_hash_value (datum key, int hashFunctionCode, uint32_t *hashValue)
	Given a hash function code, get the hash value for the given key. More...

mdbm_ubig_t	mdbm_get_page (MDBM db, const datum key)
	Gets the MDBM page number for a given key. More...

int	mdbm_preload (MDBM *db)
	Preload mdbm: Read every 4k bytes to force all pages into memory. More...

int	mdbm_lock_pages (MDBM *db)
	mdbm_lock_pages: Locks MDBM data pages into memory. More...

int	mdbm_unlock_pages (MDBM *db)
	mdbm_unlock_pages: Releases MDBM data pages from always staying in memory More...

Detailed Description

The Miscellaneous Group contains the API for routines that don't clearly fit into any of the other module API groups.

Function Documentation

int mdbm_get_errno ( MDBM * db )

Returns the value of internally saved errno.

Contains the value of errno that is set during some lock failures. Under other circumstances, mdbm_get_errno will not return the actual value of the errno variable.

Parameters

[in,out] db Database handle

Returns: Saved errno value, or zero if OK

int mdbm_get_hash_value	(	datum	key,
		int	hashFunctionCode,
		uint32_t *	hashValue
	)

Given a hash function code, get the hash value for the given key.

See mdbm_sethash for the list of valid hash function codes.

Parameters

[in]	key	Key
[in]	hashFunctionCode	for a valid hash function (below)
[out]	hashValue	is calculated according to the hashFunctionCode

Returns: Get Hash status

Return values

-1	Error, and errno is set
0	Success

Values for hashFunctionCode:

MDBM_HASH_CRC32 - Table based 32bit CRC
MDBM_HASH_EJB - From hsearch
MDBM_HASH_PHONG - Congruential hash
MDBM_HASH_OZ - From sdbm
MDBM_HASH_TOREK - From BerkeleyDB
MDBM_HASH_FNV - Fowler/Vo/Noll hash (DEFAULT)
MDBM_HASH_STL - STL string hash
MDBM_HASH_MD5 - MD5
MDBM_HASH_SHA_1 - SHA_1
MDBM_HASH_JENKINS - Jenkins string
MDBM_HASH_HSIEH - Hsieh SuperFast

mdbm_ubig_t mdbm_get_page	(	MDBM *	db,
		const datum *	key
	)

Gets the MDBM page number for a given key.

The key does not actually have to exist.

Parameters

[in,out]	db	Database handle
[in]	key	Lookup key

Returns: Page number or error indicator

Return values

-1	Error, and errno is set
Page	number where the parameter key would be stored.

int mdbm_preload ( MDBM * db )

Preload mdbm: Read every 4k bytes to force all pages into memory.

Parameters

[in,out] db Database handle

Returns: preload status

Return values

-1	Error
0	Success

int mdbm_lock_pages ( MDBM * db )

mdbm_lock_pages: Locks MDBM data pages into memory.

When running MDBM as root, mdbm_lock_pages will expand the amount of RAM that can be locked to infinity using setrlimit(RLIMIT_MEMLOCK). When not running as root, mdbm_lock_pages will expand the amount of RAM that can be locked up to the maximum allowed (retrieved using getrlimit(MEMLOCK), and normally a very small amount), and if the MDBM is larger than the amount of RAM that can be locked, a warning will be logged but mdbm_lock_pages will return 0 for success.

Parameters

[in,out] db Database handle

Returns: lock pages status

Return values

-1	Error
0	Success

int mdbm_unlock_pages ( MDBM * db )

mdbm_unlock_pages: Releases MDBM data pages from always staying in memory

Parameters

[in,out] db Database handle

Returns: unlock pages status

Return values

-1	Error
0	Success

Functions

Detailed Description

Function Documentation