lmdb::env Class Reference

Resource class for MDB_env* handles. More...

#include <lmdb++.h>

Public Member Functions
	env (MDB_env *const handle) noexcept
	Constructor.
	env (env &&other) noexcept
	Move constructor.
env &	operator= (env &&other) noexcept
	Move assignment operator.
	~env () noexcept
	Destructor.
	operator MDB_env * () const noexcept
	Returns the underlying MDB_env* handle.
MDB_env *	handle () const noexcept
	Returns the underlying MDB_env* handle.
void	sync (const bool force=true)
	Flushes data buffers to disk.
void	close () noexcept
	Closes this environment, releasing the memory map.
int	reader_check ()
env &	open (const char *const path, const unsigned int flags=default_flags, const modemode modemode=default_mode)
	Opens this environment.
env &	set_flags (const unsigned int flags, const bool onoff=true)
env &	set_mapsize (const std::size_t size)
env &	set_max_readers (const unsigned int count)
env &	set_max_dbs (const MDB_dbi count)
mdb_filehandle_t	get_fd ()
std::string_view	get_internal_map ()
	@notice WARNING: This is a function to access LMDB's internal memory map, use at your own risk!

Static Public Member Functions
static env	create (const unsigned int flags=default_flags)
	Creates a new LMDB environment.

Static Public Attributes
static constexpr unsigned int	default_flags = 0
static constexpr mode	default_mode = 0644

Protected Attributes
MDB_env *	_handle {nullptr}

Detailed Description

Resource class for MDB_env* handles.

Note

Instances of this class are movable, but not copyable.

See also

http://symas.com/mdb/doc/group__internal.html#structMDB__env

Constructor & Destructor Documentation

env() [1/2]

lmdb::env::env ( MDB_env *const handle )

inlinenoexcept

Constructor.

Parameters

handle

a valid MDB_env* handle

env() [2/2]

lmdb::env::env ( env && other )

inlinenoexcept

Move constructor.

~env()

lmdb::env::~env ( )

inlinenoexcept

Destructor.

Member Function Documentation

close()

void lmdb::env::close ( )

inlinenoexcept

Closes this environment, releasing the memory map.

Note

this method is idempotent

Postcondition

handle() == nullptr

create()

env lmdb::env::create ( const unsigned int flags = default_flags )

inlinestatic

Creates a new LMDB environment.

Parameters

flags

Exceptions

lmdb::error

on failure

get_fd()

mdb_filehandle_t lmdb::env::get_fd ( )

inline

get_internal_map()

std::string_view lmdb::env::get_internal_map ( )

inline

@notice WARNING: This is a function to access LMDB's internal memory map, use at your own risk!

handle()

MDB_env * lmdb::env::handle ( ) const

inlinenoexcept

Returns the underlying MDB_env* handle.

open()

env & lmdb::env::open ( const char *const path, const unsigned int flags = default_flags, const mode mode = default_mode )

inline

Opens this environment.

Parameters

path
flags
mode

Exceptions

lmdb::error

on failure

operator MDB_env *()

lmdb::env::operator MDB_env * ( ) const

inlinenoexcept

Returns the underlying MDB_env* handle.

operator=()

env & lmdb::env::operator= ( env && other )

inlinenoexcept

Move assignment operator.

reader_check()

int lmdb::env::reader_check ( )

inline

set_flags()

env & lmdb::env::set_flags ( const unsigned int flags, const bool onoff = true )

inline

Parameters

flags
onoff

Exceptions

lmdb::error

on failure

set_mapsize()

env & lmdb::env::set_mapsize ( const std::size_t size )

inline

Parameters

size

Exceptions

lmdb::error

on failure

set_max_dbs()

env & lmdb::env::set_max_dbs ( const MDB_dbi count )

inline

Parameters

count

Exceptions

lmdb::error

on failure

set_max_readers()

env & lmdb::env::set_max_readers ( const unsigned int count )

inline

Parameters

count

Exceptions

lmdb::error

on failure

sync()

void lmdb::env::sync ( const bool force = true )

inline

Flushes data buffers to disk.

Parameters

force

Exceptions

lmdb::error

on failure

Member Data Documentation

_handle

MDB_env* lmdb::env::_handle {nullptr}

protected

default_flags

unsigned int lmdb::env::default_flags = 0

staticconstexpr

default_mode

mode lmdb::env::default_mode = 0644

staticconstexpr

---

The documentation for this class was generated from the following file:

• lmdb++.h