A Lock-free buffer implementation to read and write data of type T in a FIFO way. More...

#include <rtt/base/BufferLockFree.hpp>

Inheritance diagram for RTT::base::BufferLockFree< T >:

Public Types
typedef BufferInterface< T > ::reference_t	reference_t
typedef BufferInterface< T > ::param_t	param_t
typedef BufferInterface< T > ::size_type	size_type
typedef T	value_t
typedef boost::shared_ptr < BufferInterface< T > >	shared_ptr
Public Member Functions
	BufferLockFree (unsigned int bufsize, const T &initial_value=T(), bool circular=false)
	Create a lock-free buffer wich can store bufsize elements.
virtual void	data_sample (const T &sample)
	Initializes this buffer with a data sample, such that for dynamical allocated types T, the buffer can reserve place to hold these elements.
virtual T	data_sample () const
	Reads back a data sample.
size_type	capacity () const
	Returns the maximum number of items that can be stored in the buffer.
size_type	size () const
	Returns the actual number of items that are stored in the buffer.
bool	empty () const
	Check if this buffer is empty.
bool	full () const
	Check if this buffer is full.
void	clear ()
	Clears all contents of this buffer.
bool	Push (param_t item)
	Write a single value to the buffer.
size_type	Push (const std::vector< T > &items)
	Write a sequence of values to the buffer.
bool	Pop (reference_t item)
	Read the oldest value from the buffer.
size_type	Pop (std::vector< T > &items)
	Read the whole buffer.
value_t *	PopWithoutRelease ()
	Returns a pointer to the first element in the buffer.
void	Release (value_t *item)
	Releases the pointer.

Detailed Description

template<class T>
class RTT::base::BufferLockFree< T >

A Lock-free buffer implementation to read and write data of type T in a FIFO way.

No memory allocation is done during read or write. One thread may read and any number of threads may write this buffer.

Parameters:

T	The value type to be stored in the Buffer. Example : BufferLockFree is a buffer which holds values of type A.

Definition at line 68 of file BufferLockFree.hpp.

Constructor & Destructor Documentation

template<class T >

RTT::base::BufferLockFree< T >::BufferLockFree	(	unsigned int	bufsize,
		const T &	initial_value = `T()`,
		bool	circular = `false`
	)		`[inline]`

Create a lock-free buffer wich can store bufsize elements.

Parameters:

bufsize the capacity of the buffer. '

Definition at line 87 of file BufferLockFree.hpp.

References RTT::internal::TsPool< T >::data_sample().

Member Function Documentation

template<class T >

size_type RTT::base::BufferLockFree< T >::capacity ( ) const [inline, virtual]

Returns the maximum number of items that can be stored in the buffer.

Returns:: maximum number of items.

Implements RTT::base::BufferBase.

Definition at line 115 of file BufferLockFree.hpp.

References RTT::internal::AtomicMWSRQueue< T >::capacity().

Referenced by RTT::base::BufferLockFree< T >::Push().

template<class T >

void RTT::base::BufferLockFree< T >::clear ( ) [inline, virtual]

Clears all contents of this buffer.

Implements RTT::base::BufferBase.

Definition at line 135 of file BufferLockFree.hpp.

References RTT::internal::AtomicMWSRQueue< T >::dequeue().

template<class T >

virtual void RTT::base::BufferLockFree< T >::data_sample ( const T & sample ) [inline, virtual]

Initializes this buffer with a data sample, such that for dynamical allocated types T, the buffer can reserve place to hold these elements.

Postcondition:: Calling this function causes all data in the buffer to be lost and the size being reset to zero.

Implements RTT::base::BufferInterface< T >.

Definition at line 98 of file BufferLockFree.hpp.

References RTT::internal::TsPool< T >::data_sample().

template<class T >

bool RTT::base::BufferLockFree< T >::empty ( ) const [inline, virtual]

Check if this buffer is empty.

Returns:: true if size() == 0

Implements RTT::base::BufferBase.

Definition at line 125 of file BufferLockFree.hpp.

References RTT::internal::AtomicMWSRQueue< T >::isEmpty().

template<class T >

bool RTT::base::BufferLockFree< T >::full ( ) const [inline, virtual]

Check if this buffer is full.

Returns:: true if size() == capacity()

Implements RTT::base::BufferBase.

Definition at line 130 of file BufferLockFree.hpp.

References RTT::internal::AtomicMWSRQueue< T >::isFull().

template<class T >

bool RTT::base::BufferLockFree< T >::Pop ( reference_t item ) [inline, virtual]

Read the oldest value from the buffer.

Parameters:

item	is to be set with a value from the buffer.

Returns:: true if something was read.

Implements RTT::base::BufferInterface< T >.

Definition at line 194 of file BufferLockFree.hpp.

References RTT::internal::AtomicMWSRQueue< T >::dequeue().

template<class T >

size_type RTT::base::BufferLockFree< T >::Pop ( std::vector< T > & items ) [inline, virtual]

Read the whole buffer.

Parameters:

items is to be filled with all values in the buffer, with items.begin() the oldest value.

Returns:: the number of items read.

Implements RTT::base::BufferInterface< T >.

Definition at line 205 of file BufferLockFree.hpp.

References RTT::internal::AtomicMWSRQueue< T >::dequeue().

template<class T >

value_t* RTT::base::BufferLockFree< T >::PopWithoutRelease ( ) [inline, virtual]

Returns a pointer to the first element in the buffer.

The pointer is only garanteed to stay valid until the next pop operation.

Note the pointer needs the be released by calling Release on the buffer.

Returns:: a pointer to a sample or Zero if buffer is empty

Implements RTT::base::BufferInterface< T >.

Definition at line 217 of file BufferLockFree.hpp.

References RTT::internal::AtomicMWSRQueue< T >::dequeue().

template<class T >

bool RTT::base::BufferLockFree< T >::Push ( param_t item ) [inline, virtual]

Write a single value to the buffer.

Parameters:

item	the value to write

Returns:: false if the buffer is full.

Implements RTT::base::BufferInterface< T >.

Definition at line 142 of file BufferLockFree.hpp.

References RTT::base::BufferLockFree< T >::capacity(), RTT::internal::AtomicMWSRQueue< T >::dequeue(), RTT::internal::AtomicMWSRQueue< T >::enqueue(), and RTT::internal::AtomicMWSRQueue< T >::size().

Referenced by RTT::base::BufferLockFree< T >::Push().

template<class T >

size_type RTT::base::BufferLockFree< T >::Push ( const std::vector< T > & items ) [inline, virtual]

Write a sequence of values to the buffer.

Parameters:

items the values to write

Returns:: the number of values written (may be less than items.size())

Implements RTT::base::BufferInterface< T >.

Definition at line 181 of file BufferLockFree.hpp.

References RTT::base::BufferLockFree< T >::Push().

template<class T >

void RTT::base::BufferLockFree< T >::Release ( value_t * item ) [inline, virtual]

Releases the pointer.

Parameters:

item	pointer aquired using PopWithoutRelease()

Implements RTT::base::BufferInterface< T >.

Definition at line 225 of file BufferLockFree.hpp.

template<class T >

size_type RTT::base::BufferLockFree< T >::size ( ) const [inline, virtual]

Returns the actual number of items that are stored in the buffer.

Returns:: number of items.

Implements RTT::base::BufferBase.

Definition at line 120 of file BufferLockFree.hpp.

References RTT::internal::AtomicMWSRQueue< T >::size().

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

rtt/base/BufferLockFree.hpp

Public Types

Public Member Functions

Detailed Description

template<class T> class RTT::base::BufferLockFree< T >

Constructor & Destructor Documentation

Member Function Documentation

template<class T>
class RTT::base::BufferLockFree< T >