#include <ListLockFree.hpp>

Inheritance diagram for RTT::internal::ListLockFree< T >:

Classes
struct	Item

struct	StorageImpl

Public Types
typedef T	value_t

Public Member Functions
bool	append (value_t item)

size_t	append (const std::vector< T > &items)

template<class Function >
void	apply (Function func)

template<class Function >
void	apply_and_blank (Function func, value_t blank)

value_t	back () const

size_t	capacity () const

void	clear ()

template<typename Pred >
bool	delete_if (Pred pred)

bool	empty () const

bool	erase (value_t item)

bool	erase_and_blank (value_t item, value_t blank)

template<class Function >
value_t	find_if (Function func, value_t blank=value_t())

value_t	front () const

void	grow (size_t items=1)

	ListLockFree (unsigned int lsize, unsigned int threads=ORONUM_OS_MAX_THREADS)

void	reserve (size_t lsize)

void	shrink (size_t items=1)

size_t	size () const

	~ListLockFree ()

Public Attributes
const unsigned int	MAX_THREADS
	The maximum number of threads. More...

Private Types
typedef std::vector< value_t >	BufferType

typedef BufferType::const_iterator	CIterator

typedef BufferType::iterator	Iterator

typedef boost::intrusive_ptr< StorageImpl >	Storage

Private Member Functions
size_t	BufNum () const

Item *	findEmptyBuf (Storage &bufptr)

Item *	lockAndGetActive (Storage &bufptr) const

Item *	lockAndGetActive () const

Item *	lockAndGetBlank (Storage &bufptr) const

Storage	newStorage (size_t alloc, size_t items, bool init=true)

bool	pointsTo (Item *p, const Storage &bf) const

Private Attributes
Item *volatile	active

Item *volatile	blankp

Storage	bufs

size_t	required

Detailed Description

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

A simple lock-free list implementation to append or erase data of type T. If T is a value type, no memory allocation is done during appending or erasing. 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. If T is a type that does memory allocation or deallocation in copy-constructor or destructor, certain functions of this list will not be real-time. Example : ListLockFree is a list which holds values of type A.

Definition at line 85 of file ListLockFree.hpp.

Member Typedef Documentation

template<class T>

typedef std::vector<value_t> RTT::internal::ListLockFree< T >::BufferType

private

Definition at line 97 of file ListLockFree.hpp.

template<class T>

typedef BufferType::const_iterator RTT::internal::ListLockFree< T >::CIterator

private

Definition at line 99 of file ListLockFree.hpp.

template<class T>

typedef BufferType::iterator RTT::internal::ListLockFree< T >::Iterator

private

Definition at line 98 of file ListLockFree.hpp.

template<class T>

typedef boost::intrusive_ptr<StorageImpl> RTT::internal::ListLockFree< T >::Storage

private

The intrusive_ptr is far more thread-safe than the shared_ptr for 'reads' during 'assignments'.

Definition at line 126 of file ListLockFree.hpp.

template<class T>

typedef T RTT::internal::ListLockFree< T >::value_t

Definition at line 95 of file ListLockFree.hpp.

Constructor & Destructor Documentation

template<class T>

RTT::internal::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 164 of file ListLockFree.hpp.

template<class T>

RTT::internal::ListLockFree< T >::~ListLockFree ( )

inline

Definition at line 171 of file ListLockFree.hpp.

Member Function Documentation

template<class T>

bool RTT::internal::ListLockFree< T >::append ( value_t item )

inline

Append a single value to the list. This function calls the copy-constructor of item and may call the destructor of item

Parameters

item	the value to write

Returns: false if the list is full.

Note: This function is only real-time if the destructor or copy-constructor of of T is real-time.

Definition at line 344 of file ListLockFree.hpp.

template<class T>

size_t RTT::internal::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())

Note: This function is only real-time if the destructor and copy-constructor of of T is real-time.

Definition at line 401 of file ListLockFree.hpp.

template<class T>

template<class Function >

void RTT::internal::ListLockFree< T >::apply ( Function func )

inline

Apply a function to the elements of the whole list.

Parameters

func	The function to apply.

Note: Always real-time.

Definition at line 524 of file ListLockFree.hpp.

template<class T>

template<class Function >

void RTT::internal::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.

Note: This function is only real-time if the destructor and copy-constructor of of T is real-time.

Definition at line 552 of file ListLockFree.hpp.

template<class T>

value_t RTT::internal::ListLockFree< T >::back ( ) const

inline

Returns the last element of the list.

Definition at line 385 of file ListLockFree.hpp.

template<class T>

size_t RTT::internal::ListLockFree< T >::BufNum ( ) const

inlineprivate

Definition at line 150 of file ListLockFree.hpp.

template<class T>

size_t RTT::internal::ListLockFree< T >::capacity ( ) const

inline

Returns the maximum number of elements this list can hold.

Note: Always real-time.

Definition at line 178 of file ListLockFree.hpp.

template<class T>

void RTT::internal::ListLockFree< T >::clear ( )

inline

Clears all elements in the list.

Postcondition: this->empty() == true

Note: This function is not real-time if the destructor of of T is not real-time.

Definition at line 316 of file ListLockFree.hpp.

template<class T>

template<typename Pred >

bool RTT::internal::ListLockFree< T >::delete_if ( Pred pred )

inline

Erase a value from the list.

Parameters

function each elements for which pred returns true are removed

Returns: true if at least one element has been removed

Note: This function is only real-time if the destructor and copy-constructor of of T is real-time.

Definition at line 480 of file ListLockFree.hpp.

template<class T>

bool RTT::internal::ListLockFree< T >::empty ( ) const

inline

Returns true if this list is empty.

Note: Always real-time.

Definition at line 206 of file ListLockFree.hpp.

template<class T>

bool RTT::internal::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.

Note: This function is only real-time if the destructor and copy-constructor of of T is real-time.

Definition at line 438 of file ListLockFree.hpp.

template<class T>

bool RTT::internal::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.

Note: This function is only real-time if the destructor and copy-constructor of of T is real-time.

Definition at line 597 of file ListLockFree.hpp.

template<class T>

template<class Function >

value_t RTT::internal::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.

Note: This function is only real-time if the copy-constructor of of T is real-time.

Definition at line 626 of file ListLockFree.hpp.

template<class T>

Item* RTT::internal::ListLockFree< T >::findEmptyBuf ( Storage & bufptr )

inlineprivate

Item returned is guaranteed to point into bufptr. This function calls all destructors of all old elements in the empty buf, by using the std::vector::clear() function. This means that if a destructor of T is not real-time, all functions calling this function are not real-time as well. For example, append() and erase().

Definition at line 649 of file ListLockFree.hpp.

template<class T>

value_t RTT::internal::ListLockFree< T >::front ( ) const

inline

Returns the first element of the list.

Note: This function is only real-time if the copy-constructor of of T is real-time.

Definition at line 373 of file ListLockFree.hpp.

template<class T>

void RTT::internal::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.

Note: Almost never real-time.

Definition at line 224 of file ListLockFree.hpp.

template<class T>

Item* RTT::internal::ListLockFree< T >::lockAndGetActive ( Storage & bufptr ) const

inlineprivate

Item returned is guaranteed to point into bufptr.

Note: Always real-time.

Definition at line 670 of file ListLockFree.hpp.

template<class T>

Item* RTT::internal::ListLockFree< T >::lockAndGetActive ( ) const

inlineprivate

Only to be used by reserve() ! Caller must guarantee that active points to valid memory.

Note: Always real-time

Definition at line 698 of file ListLockFree.hpp.

template<class T>

Item* RTT::internal::ListLockFree< T >::lockAndGetBlank ( Storage & bufptr ) const

inlineprivate

Get the blank buffer or null if no apply_and_blank operation going on.

Definition at line 716 of file ListLockFree.hpp.

template<class T>

Storage RTT::internal::ListLockFree< T >::newStorage	(	size_t	alloc,
		size_t	items,
		bool	init = `true`
	)

inlineprivate

Definition at line 128 of file ListLockFree.hpp.

template<class T>

bool RTT::internal::ListLockFree< T >::pointsTo	(	Item *	p,
		const Storage &	bf
	)		const

inlineprivate

Definition at line 739 of file ListLockFree.hpp.

template<class T>

void RTT::internal::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(). @ Not real-time if lsize <= this->capacity().

Definition at line 252 of file ListLockFree.hpp.

template<class T>

void RTT::internal::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.

Note: Always real-time.

Definition at line 238 of file ListLockFree.hpp.

template<class T>

size_t RTT::internal::ListLockFree< T >::size ( ) const

inline

Returns the current number of elements in this list.

Note: Always real-time.

Definition at line 192 of file ListLockFree.hpp.

Member Data Documentation

template<class T>

Item* volatile RTT::internal::ListLockFree< T >::active

private

Definition at line 144 of file ListLockFree.hpp.

template<class T>

Item* volatile RTT::internal::ListLockFree< T >::blankp

private

Definition at line 145 of file ListLockFree.hpp.

template<class T>

Storage RTT::internal::ListLockFree< T >::bufs

private

Definition at line 143 of file ListLockFree.hpp.

template<class T>

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

The maximum number of threads.

The number of threads which may concurrently access this buffer.

Definition at line 93 of file ListLockFree.hpp.

template<class T>

size_t RTT::internal::ListLockFree< T >::required

private

Definition at line 154 of file ListLockFree.hpp.

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

ListLockFree.hpp

Classes

Public Types

Public Member Functions

Public Attributes

Private Types

Private Member Functions

Private Attributes

Detailed Description

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

Member Typedef Documentation

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation

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