RTT::ListLockFree< T > Class Template Reference

A simple lock-free list implementation to append or erase data of type T. More...

#include <rtt/ListLockFree.hpp>

Inheritance diagram for RTT::ListLockFree< T >:

Public Types
typedef T	value_t
Public Member Functions
	ListLockFree (unsigned int lsize, unsigned int threads=ORONUM_OS_MAX_THREADS)
	Create a lock-free list wich can store lsize elements.
size_t	capacity () const
size_t	size () const
bool	empty () const
void	grow (size_t items=1)
	Grow the capacity to contain at least n additional items.
void	shrink (size_t items=1)
	Shrink the capacity with at most n items.
void	reserve (size_t lsize)
	Reserve a capacity for this list.
void	clear ()
bool	append (value_t item)
	Append a single value to the list.
value_t	front () const
	Returns the first element of the list.
value_t	back () const
	Returns the last element of the list.
size_t	append (const std::vector< T > &items)
	Append a sequence of values to the list.
bool	erase (value_t item)
	Erase a value from the list.
template<class Function >
void	apply (Function func)
	Apply a function to the elements of the whole list.
template<class Function >
void	apply_and_blank (Function func, value_t blank)
	Apply a function to the non-blanked elements of the list.
bool	erase_and_blank (value_t item, value_t blank)
	Erase an element from the list and blank it if possible.
template<class Function >
value_t	find_if (Function func, value_t blank=value_t())
	Find an item in the list such that func( item ) == true.
Public Attributes
const unsigned int	MAX_THREADS
	The maximum number of threads.

Detailed Description

template<class T>
class RTT::ListLockFree< T >

A simple lock-free list implementation to append or erase data of type T.

No memory allocation is done during read or write, but the maximum number of threads which can access this object is defined by MAX_THREADS.

Parameters:

T

The value type to be stored in the list. Example : ListLockFree is a list which holds values of type A.

Definition at line 81 of file ListLockFree.hpp.

Constructor & Destructor Documentation

template<class T>

RTT::ListLockFree< T >::ListLockFree	(	unsigned int	lsize,
		unsigned int	threads = `ORONUM_OS_MAX_THREADS`
	)			`[inline]`

Create a lock-free list wich can store lsize elements.

Parameters:

	lsize	the capacity of the list.
	threads	the number of threads which may concurrently read or write this buffer. Defaults to ORONUM_OS_MAX_THREADS, but you may lower this number in case not all threads will read this buffer. A lower number will consume less memory. '

Definition at line 160 of file ListLockFree.hpp.

Member Function Documentation

template<class T>

size_t RTT::ListLockFree< T >::append ( const std::vector< T > & items ) [inline]

Append a sequence of values to the list.

Parameters:

items

the values to append.

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

Definition at line 369 of file ListLockFree.hpp.

template<class T>

bool RTT::ListLockFree< T >::append ( value_t item ) [inline]

Append a single value to the list.

Parameters:

d

the value to write

Returns:: false if the list is full.

Definition at line 316 of file ListLockFree.hpp.

template<class T>

template<class Function >

void RTT::ListLockFree< T >::apply ( Function func ) [inline]

Apply a function to the elements of the whole list.

Parameters:

func

The function to apply.

Definition at line 443 of file ListLockFree.hpp.

template<class T>

template<class Function >

void RTT::ListLockFree< T >::apply_and_blank	(	Function	func,
		value_t	blank
	)			`[inline]`

Apply a function to the non-blanked elements of the list.

If during an apply_and_blank, the erase_and_blank function is called, that element will not be subject to func if not yet processed. You must not call this function concurrently from multiple threads.

Parameters:

	func	The function to apply.
	blank	The 'blank' item. Each item of this list will be compared to this item using operator==(), if it matches, it is considered blank, and func is not applied.

See also:: erase_and_blank

Deprecated:: This complicated function is nowhere used.

Definition at line 469 of file ListLockFree.hpp.

template<class T>

bool RTT::ListLockFree< T >::erase ( value_t item ) [inline]

Erase a value from the list.

Parameters:

item

is to be erased from the list.

Returns:: true if found and erased.

Definition at line 404 of file ListLockFree.hpp.

Referenced by RTT::ListLockFree< detail::EventCatcher * >::erase_and_blank().

template<class T>

bool RTT::ListLockFree< T >::erase_and_blank	(	value_t	item,
		value_t	blank
	)			`[inline]`

Erase an element from the list and blank it if possible.

If during an apply_and_blank, the erase_and_blank function is called, that element will not be subject to func if not yet processed. You may call this function concurrently from multiple threads.

Warning:: It is possible that item is being processed within apply_and_blank. In that case the 'blank' operation has no effect.

Parameters:

	item	The item to erase from the list.
	blank	The 'blank' item to use to blank item from the list.

See also:: apply_and_blank

Deprecated:: This complicated function is nowhere used.

Definition at line 512 of file ListLockFree.hpp.

template<class T>

template<class Function >

value_t RTT::ListLockFree< T >::find_if	(	Function	func,
		value_t	blank = `value_t()`
	)			`[inline]`

Find an item in the list such that func( item ) == true.

Parameters:

blank

The value to return if not found.

Returns:: The item that matches func(item) or blank if none matches.

Definition at line 539 of file ListLockFree.hpp.

template<class T>

void RTT::ListLockFree< T >::grow ( size_t items = 1 ) [inline]

Grow the capacity to contain at least n additional items.

This method tries to avoid too much re-allocations, by growing a bit more than required every N invocations and growing nothing in between.

Parameters:

items

The number of items to at least additionally reserve.

Definition at line 207 of file ListLockFree.hpp.

template<class T>

void RTT::ListLockFree< T >::reserve ( size_t lsize ) [inline]

Reserve a capacity for this list.

If you wish to invoke this method concurrently, guard it with a mutex. The other methods may be invoked concurrently with this method.

Parameters:

lsize

the minimal number of items this list will be able to hold. Will not drop below the current capacity() and this method will do nothing if lsize < this->capacity().

Definition at line 233 of file ListLockFree.hpp.

Referenced by RTT::ListLockFree< detail::EventCatcher * >::grow().

template<class T>

void RTT::ListLockFree< T >::shrink ( size_t items = 1 ) [inline]

Shrink the capacity with at most n items.

This method does not actually free memory, it just prevents a (number of) subsequent grow() invocations to allocate more memory.

Parameters:

items

The number of items to at most remove from the capacity.

Definition at line 220 of file ListLockFree.hpp.

Member Data Documentation

template<class T>

const unsigned int RTT::ListLockFree< T >::MAX_THREADS

The maximum number of threads.

The number of threads which may concurrently access this buffer.

Definition at line 89 of file ListLockFree.hpp.

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

rtt/ListLockFree.hpp

RTT::ListLockFree< T > Class Template Reference

Public Types

Public Member Functions

Public Attributes

Detailed Description

template<class T> class RTT::ListLockFree< T >

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation

template<class T>
class RTT::ListLockFree< T >