A simple triple buffer for lockfree comunication between a single writer and a single reader. More...

#include <ArmarXCore/util/CPPUtility/TripleBuffer.h>

Public Member Functions
T &	_getNonConstHiddenBuffer ()

T &	_getNonConstReadBuffer ()

void	commitWrite ()

const T &	getReadBuffer () const

const T &	getUpToDateReadBuffer () const

T &	getWriteBuffer ()

const T &	getWriteBuffer () const

template<class U = T>
std::enable_if< std::is_copy_constructible< U >::value >::type	reinitAllBuffers (const T &init)

void	reinitAllBuffers (T &&writeBuff, T &&hiddenBuff, T &&readBuff)

void	setDebugMode (bool mode)

template<class... Ts>
	TripleBuffer (const Ts &... ts)

	TripleBuffer (T &&initR, T &&initH, T &&initW)

bool	updateReadBuffer () const
	Swaps in the hidden buffer if it contains new data.

Protected Member Functions
uint_fast8_t	getHiddenBufferIndex () const

uint_fast8_t	getReadBufferIndex () const

uint_fast8_t	getWriteBufferIndex () const

bool	hasNewWrite (uint_fast8_t flags) const

TripleBuffer &	operator= (const TripleBuffer &)=delete

void	swapWriteAndHiddenBuffer ()
	Swap the write buffer with the hidden buffer.

	TripleBuffer (const TripleBuffer &)=delete

Static Protected Member Functions
static uint_fast8_t	flagSwapReadWithHidden (uint_fast8_t flags)
	swap read and hidden indexes

static uint_fast8_t	flagSwapWriteWithHidden (uint_fast8_t flags)
	swap write and hidden indexes of given flags (set dirty to 1)

Protected Attributes
T	buffer [3]

std::atomic_bool	debugMode {false}

std::atomic_uint_fast8_t	flags {initialFlags}

Static Protected Attributes
static const uint_fast8_t	dirtyBitMask = 1 << dirtyBitShift

static const uint_fast8_t	dirtyBitShift = 7

static const uint_fast8_t	hiddenBufferIndexMask = 3 << hiddenBufferIndexShift

static const uint_fast8_t	hiddenBufferIndexShift = 2

static const uint_fast8_t	hiddenToReadShift = hiddenBufferIndexShift - readBufferIndexShift

static const uint_fast8_t	hiddenToWriteShift

static const uint_fast8_t	initialFlags = 2 + (1 << 2)

static const uint_fast8_t	readBufferIndexMask = 3 << readBufferIndexShift

static const uint_fast8_t	readBufferIndexShift = 0

static const uint_fast8_t	writeBufferIndexMask = 3 << writeBufferIndexShift

static const uint_fast8_t	writeBufferIndexShift = 4

Detailed Description

template<typename T>
class armarx::TripleBuffer< T >

A simple triple buffer for lockfree comunication between a single writer and a single reader.

If more than one reader/writer is required, you have to synchronize the access. Writers must not have: writes to the same data cell (except it is an atomic et al) and no writes are allowed during swapping of the buffer. Readers must not read when the buffer is swapped. If a writer only writes parts of the data structure, data loss could occure! (use a WriteBufferedTripleBuffer instead)

Constructor & Destructor Documentation

◆ TripleBuffer() [1/3]

template<typename T>

TripleBuffer	(	T &&	initR,
		T &&	initH,
		T &&	initW )

inline

◆ TripleBuffer() [2/3]

template<typename T>

template<class... Ts>

TripleBuffer ( const Ts &... ts )

inline

◆ TripleBuffer() [3/3]

template<typename T>

TripleBuffer ( const TripleBuffer< T > & )

protecteddelete

Member Function Documentation

◆ _getNonConstHiddenBuffer()

template<typename T>

T & _getNonConstHiddenBuffer ( )

inline

Returns: the current read buffer (sometimes required for more complex initialization)

◆ _getNonConstReadBuffer()

template<typename T>

T & _getNonConstReadBuffer ( )

inline

Returns: the current read buffer (sometimes required for more complex initialization)

◆ commitWrite()

template<typename T>

void commitWrite ( )

inline

◆ flagSwapReadWithHidden()

template<typename T>

static uint_fast8_t flagSwapReadWithHidden ( uint_fast8_t flags )

inlinestaticprotected

swap read and hidden indexes

swap read and hidden indexes of given flags (set dirty to 0)

Parameters

flags the current flags

Returns: the new flags

◆ flagSwapWriteWithHidden()

template<typename T>

static uint_fast8_t flagSwapWriteWithHidden ( uint_fast8_t flags )

inlinestaticprotected

swap write and hidden indexes of given flags (set dirty to 1)

Parameters

flags the current flags

Returns: the new flags

◆ getHiddenBufferIndex()

template<typename T>

uint_fast8_t getHiddenBufferIndex ( ) const

inlineprotected

◆ getReadBuffer()

template<typename T>

const T & getReadBuffer ( ) const

inline

Returns: the current read buffer

◆ getReadBufferIndex()

template<typename T>

uint_fast8_t getReadBufferIndex ( ) const

inlineprotected

◆ getUpToDateReadBuffer()

template<typename T>

const T & getUpToDateReadBuffer ( ) const

inline

Returns: the most up to date read buffer

◆ getWriteBuffer() [1/2]

template<typename T>

T & getWriteBuffer ( )

inline

Returns: the write buffer

◆ getWriteBuffer() [2/2]

template<typename T>

const T & getWriteBuffer ( ) const

inline

Returns: the write buffer

◆ getWriteBufferIndex()

template<typename T>

uint_fast8_t getWriteBufferIndex ( ) const

inlineprotected

◆ hasNewWrite()

template<typename T>

bool hasNewWrite ( uint_fast8_t flags ) const

inlineprotected

◆ operator=()

template<typename T>

TripleBuffer & operator= ( const TripleBuffer< T > & )

protecteddelete

◆ reinitAllBuffers() [1/2]

template<typename T>

template<class U = T>

std::enable_if< std::is_copy_constructible< U >::value >::type reinitAllBuffers ( const T & init )

inline

◆ reinitAllBuffers() [2/2]

template<typename T>

void reinitAllBuffers	(	T &&	writeBuff,
		T &&	hiddenBuff,
		T &&	readBuff )

inline

◆ setDebugMode()

template<typename T>

void setDebugMode ( bool mode )

inline

◆ swapWriteAndHiddenBuffer()

template<typename T>

void swapWriteAndHiddenBuffer ( )

inlineprotected

Swap the write buffer with the hidden buffer.

◆ updateReadBuffer()

template<typename T>

bool updateReadBuffer ( ) const

inline

Swaps in the hidden buffer if it contains new data.

Returns: True if new data is available

Member Data Documentation

◆ buffer

template<typename T>

T buffer[3]

protected

◆ debugMode

template<typename T>

std::atomic_bool debugMode {false}

protected

◆ dirtyBitMask

template<typename T>

const uint_fast8_t dirtyBitMask = 1 << dirtyBitShift

staticprotected

◆ dirtyBitShift

template<typename T>

const uint_fast8_t dirtyBitShift = 7

staticprotected

◆ flags

template<typename T>

std::atomic_uint_fast8_t flags {initialFlags}

mutableprotected

◆ hiddenBufferIndexMask

template<typename T>

const uint_fast8_t hiddenBufferIndexMask = 3 << hiddenBufferIndexShift

staticprotected

◆ hiddenBufferIndexShift

template<typename T>

const uint_fast8_t hiddenBufferIndexShift = 2

staticprotected

◆ hiddenToReadShift

template<typename T>

const uint_fast8_t hiddenToReadShift = hiddenBufferIndexShift - readBufferIndexShift

staticprotected

◆ hiddenToWriteShift

template<typename T>

const uint_fast8_t hiddenToWriteShift

staticprotected

Initial value:

=

writeBufferIndexShift - hiddenBufferIndexShift

armarx::TripleBuffer::writeBufferIndexShift

static const uint_fast8_t writeBufferIndexShift

Definition TripleBuffer.h:285

armarx::TripleBuffer::hiddenBufferIndexShift

static const uint_fast8_t hiddenBufferIndexShift

Definition TripleBuffer.h:284

◆ initialFlags

template<typename T>

const uint_fast8_t initialFlags = 2 + (1 << 2)

staticprotected

◆ readBufferIndexMask

template<typename T>

const uint_fast8_t readBufferIndexMask = 3 << readBufferIndexShift

staticprotected

◆ readBufferIndexShift

template<typename T>

const uint_fast8_t readBufferIndexShift = 0

staticprotected

◆ writeBufferIndexMask

template<typename T>

const uint_fast8_t writeBufferIndexMask = 3 << writeBufferIndexShift

staticprotected

◆ writeBufferIndexShift

template<typename T>

const uint_fast8_t writeBufferIndexShift = 4

staticprotected

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

ArmarXCore/util/CPPUtility/TripleBuffer.h

Public Member Functions

Protected Member Functions

Static Protected Member Functions

Protected Attributes

Static Protected Attributes

Detailed Description

Constructor & Destructor Documentation

◆ TripleBuffer() [1/3]

◆ TripleBuffer() [2/3]

◆ TripleBuffer() [3/3]

Member Function Documentation

◆ _getNonConstHiddenBuffer()

◆ _getNonConstReadBuffer()

◆ commitWrite()

◆ flagSwapReadWithHidden()

◆ flagSwapWriteWithHidden()

◆ getHiddenBufferIndex()

◆ getReadBuffer()

◆ getReadBufferIndex()

◆ getUpToDateReadBuffer()

◆ getWriteBuffer() [1/2]

◆ getWriteBuffer() [2/2]

◆ getWriteBufferIndex()

◆ hasNewWrite()

◆ operator=()

◆ reinitAllBuffers() [1/2]

◆ reinitAllBuffers() [2/2]

◆ setDebugMode()

◆ swapWriteAndHiddenBuffer()

◆ updateReadBuffer()

Member Data Documentation

◆ buffer

◆ debugMode

◆ dirtyBitMask

◆ dirtyBitShift

◆ flags

◆ hiddenBufferIndexMask

◆ hiddenBufferIndexShift

◆ hiddenToReadShift

◆ hiddenToWriteShift

◆ initialFlags

◆ readBufferIndexMask

◆ readBufferIndexShift

◆ writeBufferIndexMask

◆ writeBufferIndexShift