Orocos Real-Time Toolkit  2.8.3
Public Types | Public Member Functions | List of all members
RTT::base::BufferLockFree< T > Class Template Reference

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 >:
RTT::base::BufferInterface< T > RTT::base::BufferBase RTT::base::Buffer< 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. More...
 
 ~BufferLockFree ()
 
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. More...
 
virtual T data_sample () const
 Reads back a data sample. More...
 
size_type capacity () const
 Returns the maximum number of items that can be stored in the buffer. More...
 
size_type size () const
 Returns the actual number of items that are stored in the buffer. More...
 
bool empty () const
 Check if this buffer is empty. More...
 
bool full () const
 Check if this buffer is full. More...
 
void clear ()
 Clears all contents of this buffer. More...
 
virtual size_type dropped () const
 Returns the number of dropped samples, because the buffer was full. More...
 
bool Push (param_t item)
 Write a single value to the buffer. More...
 
size_type Push (const std::vector< T > &items)
 Write a sequence of values to the buffer. More...
 
bool Pop (reference_t item)
 Read the oldest value from the buffer. More...
 
size_type Pop (std::vector< T > &items)
 Read the whole buffer. More...
 
value_tPopWithoutRelease ()
 Returns a pointer to the first element in the buffer. More...
 
void Release (value_t *item)
 Releases the pointer. More...
 

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

Definition at line 69 of file BufferLockFree.hpp.

Member Typedef Documentation

template<class T>
typedef BufferInterface<T>::param_t RTT::base::BufferLockFree< T >::param_t

Definition at line 74 of file BufferLockFree.hpp.

Definition at line 73 of file BufferLockFree.hpp.

template<class T>
typedef boost::shared_ptr< BufferInterface<T> > RTT::base::BufferInterface< T >::shared_ptr
inherited

Definition at line 62 of file BufferInterface.hpp.

template<class T>
typedef BufferInterface<T>::size_type RTT::base::BufferLockFree< T >::size_type

Definition at line 75 of file BufferLockFree.hpp.

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

Definition at line 76 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
bufsizethe capacity of the buffer. '

Definition at line 90 of file BufferLockFree.hpp.

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

template<class T>
RTT::base::BufferLockFree< T >::~BufferLockFree ( )
inline

Definition at line 96 of file BufferLockFree.hpp.

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

Member Function Documentation

template<class T>
size_type RTT::base::BufferLockFree< T >::capacity ( ) const
inlinevirtual

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 118 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 ( )
inlinevirtual
template<class T>
virtual void RTT::base::BufferLockFree< T >::data_sample ( const T &  sample)
inlinevirtual

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 101 of file BufferLockFree.hpp.

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

template<class T>
virtual T RTT::base::BufferLockFree< T >::data_sample ( ) const
inlinevirtual

Reads back a data sample.

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

Definition at line 106 of file BufferLockFree.hpp.

References RTT::internal::TsPool< T >::allocate(), and RTT::internal::TsPool< T >::deallocate().

template<class T>
virtual size_type RTT::base::BufferLockFree< T >::dropped ( ) const
inlinevirtual

Returns the number of dropped samples, because the buffer was full.

Implements RTT::base::BufferBase.

Definition at line 145 of file BufferLockFree.hpp.

References RTT::os::AtomicInt::read().

template<class T>
bool RTT::base::BufferLockFree< T >::empty ( ) const
inlinevirtual

Check if this buffer is empty.

Returns
true if size() == 0

Implements RTT::base::BufferBase.

Definition at line 128 of file BufferLockFree.hpp.

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

template<class T>
bool RTT::base::BufferLockFree< T >::full ( ) const
inlinevirtual

Check if this buffer is full.

Returns
true if size() == capacity()

Implements RTT::base::BufferBase.

Definition at line 133 of file BufferLockFree.hpp.

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

template<class T>
bool RTT::base::BufferLockFree< T >::Pop ( reference_t  item)
inlinevirtual

Read the oldest value from the buffer.

Parameters
itemis to be set with a value from the buffer.
Returns
true if something was read.

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

Definition at line 221 of file BufferLockFree.hpp.

References RTT::internal::TsPool< T >::deallocate(), and RTT::internal::AtomicMWSRQueue< T >::dequeue().

template<class T>
size_type RTT::base::BufferLockFree< T >::Pop ( std::vector< T > &  items)
inlinevirtual

Read the whole buffer.

Parameters
itemsis 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 232 of file BufferLockFree.hpp.

References RTT::internal::TsPool< T >::deallocate(), and RTT::internal::AtomicMWSRQueue< T >::dequeue().

template<class T>
value_t* RTT::base::BufferLockFree< T >::PopWithoutRelease ( )
inlinevirtual

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 244 of file BufferLockFree.hpp.

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

template<class T>
bool RTT::base::BufferLockFree< T >::Push ( param_t  item)
inlinevirtual
template<class T>
size_type RTT::base::BufferLockFree< T >::Push ( const std::vector< T > &  items)
inlinevirtual

Write a sequence of values to the buffer.

Parameters
itemsthe values to write
Returns
the number of values written (may be less than items.size())

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

Definition at line 204 of file BufferLockFree.hpp.

References RTT::os::AtomicInt::add(), and RTT::base::BufferLockFree< T >::Push().

template<class T>
void RTT::base::BufferLockFree< T >::Release ( value_t item)
inlinevirtual

Releases the pointer.

Parameters
itempointer aquired using PopWithoutRelease()

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

Definition at line 252 of file BufferLockFree.hpp.

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

template<class T>
size_type RTT::base::BufferLockFree< T >::size ( ) const
inlinevirtual

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

Returns
number of items.

Implements RTT::base::BufferBase.

Definition at line 123 of file BufferLockFree.hpp.

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


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