join::ShmMem Class Reference

posix shared memory provider. More...

#include <memory.hpp>

Public Types
template<size_t Count, size_t... Sizes>
using	Allocator = BasicArena<ShmMem, Count, Sizes...>
using	Spsc = SyncBinding<ShmMem, ::join::Spsc>
using	Mpsc = SyncBinding<ShmMem, ::join::Mpsc>
using	Mpmc = SyncBinding<ShmMem, ::join::Mpmc>

Public Member Functions
	ShmMem (uint64_t size, const std::string &name)
	creates or opens a named shared memory segment.
	ShmMem (const ShmMem &other)=delete
	copy constructor.
ShmMem &	operator= (const ShmMem &other)=delete
	copy assignment operator.
	ShmMem (ShmMem &&other) noexcept
	move constructor.
ShmMem &	operator= (ShmMem &&other) noexcept
	move assignment operator.
	~ShmMem () noexcept
	unmaps the memory and closes the file descriptor.
const void *	get (uint64_t offset=0) const
	get a const pointer to the shared memory at a given offset.
void *	get (uint64_t offset=0)
	get a pointer to the shared memory at a given offset.
int	mbind (int numa) const noexcept
	bind memory to a NUMA node.
int	mlock () const noexcept
	lock memory in RAM.

Static Public Member Functions
static int	unlink (const std::string &name) noexcept
	destroy synchronization primitives and unlink the shared memory segment.

Detailed Description

posix shared memory provider.

Member Typedef Documentation

Allocator

template<size_t Count, size_t... Sizes>

using join::ShmMem::Allocator = BasicArena<ShmMem, Count, Sizes...>

Mpmc

using join::ShmMem::Mpmc = SyncBinding<ShmMem, ::join::Mpmc>

Mpsc

using join::ShmMem::Mpsc = SyncBinding<ShmMem, ::join::Mpsc>

Spsc

using join::ShmMem::Spsc = SyncBinding<ShmMem, ::join::Spsc>

Constructor & Destructor Documentation

ShmMem() [1/3]

join::ShmMem::ShmMem ( uint64_t size, const std::string & name )

inlineexplicit

creates or opens a named shared memory segment.

Parameters

size	shared memory size in bytes.
name	shared memory unique name.

Exceptions

std::system_error

if mmap fails.

ShmMem() [2/3]

join::ShmMem::ShmMem ( const ShmMem & other )

delete

copy constructor.

Parameters

other

other object to copy.

ShmMem() [3/3]

join::ShmMem::ShmMem ( ShmMem && other )

inlinenoexcept

move constructor.

Parameters

other

other object to move.

~ShmMem()

join::ShmMem::~ShmMem ( )

inlinenoexcept

unmaps the memory and closes the file descriptor.

Member Function Documentation

get() [1/2]

void * join::ShmMem::get ( uint64_t offset = 0 )

inline

get a pointer to the shared memory at a given offset.

Parameters

offset

byte offset from the start of the shared memory.

Returns

pointer to the mapped memory at the specified offset, or nullptr if not opened.

Exceptions

std::runtime_error	if memory is not mapped.
std::out_of_range	if offset is out of bounds.

get() [2/2]

const void * join::ShmMem::get ( uint64_t offset = 0 ) const

inline

get a const pointer to the shared memory at a given offset.

Parameters

offset

byte offset from the start of the shared memory.

Returns

pointer to the mapped memory at the specified offset, or nullptr if not opened.

Exceptions

std::runtime_error	if memory is not mapped.
std::out_of_range	if offset is out of bounds.

mbind()

int join::ShmMem::mbind ( int numa ) const

inlinenoexcept

bind memory to a NUMA node.

Parameters

numa	NUMA node ID.

Returns

0 on success, -1 on failure.

mlock()

int join::ShmMem::mlock ( ) const

inlinenoexcept

lock memory in RAM.

Returns

0 on success, -1 on failure.

operator=() [1/2]

ShmMem & join::ShmMem::operator= ( const ShmMem & other )

delete

copy assignment operator.

Parameters

other

other object to copy.

Returns

this.

operator=() [2/2]

ShmMem & join::ShmMem::operator= ( ShmMem && other )

inlinenoexcept

move assignment operator.

Parameters

other

other object to move.

Returns

this.

unlink()

static int join::ShmMem::unlink ( const std::string & name )

inlinestaticnoexcept

destroy synchronization primitives and unlink the shared memory segment.

Parameters

name	shared memory segment name.

Returns

0 on success, -1 on failure.

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

• core/include/join/memory.hpp