stxxl::counting_ptr< Type > Class Template Reference

Detailed Description

template<class Type>
class stxxl::counting_ptr< Type >

High-performance smart pointer used as a wrapping reference counting pointer.

This smart pointer class requires two functions in the templated type: void inc_reference() and void dec_reference(). These must increment and decrement a reference counter inside the templated object. When initialized, the type must have reference count zero. It is not immediately called with add_reference(). Each new object referencing the data calls add_reference() and each destroying holder calls del_reference(). When the data object determines that it's internal counter is zero, then it must destroy itself.

Accompanying the counting_ptr is a const_counting_ptr and a class counted_object, from which reference counted classes must be derive from. The class counted_object implement all methods required for reference counting.

The whole method is more similar to boost' instrusive_ptr, but also yields something resembling shared_ptr.

Definition at line 48 of file counting_ptr.h.

Inheritance diagram for stxxl::counting_ptr< Type >:

Public Types
typedef Type	element_type
	contained type. More...

Public Member Functions
	counting_ptr ()
	default constructor: contains a NULL pointer. More...
	counting_ptr (Type *ptr)
	constructor with pointer: initializes new reference to ptr. More...
	counting_ptr (const counting_ptr &other_ptr)
	copy-constructor: also initializes new reference to ptr. More...
	~counting_ptr ()
	destructor: decrements reference counter in ptr. More...
bool	empty () const
	test for a NULL pointer More...
Type *	get () const
	return the enclosed pointer. More...
	operator bool () const
	cast to bool check for a NULL pointer More...
	operator Type * () const
	implicit cast to the enclosed pointer. More...
bool	operator!= (const counting_ptr &other_ptr) const
	test inequality of only the pointer values. More...
Type &	operator* () const
	return the enclosed object as reference. More...
Type *	operator-> () const
	return the enclosed pointer. More...
counting_ptr &	operator= (const counting_ptr &other_ptr)
	assignment operator: dereference current object and acquire reference on new one. More...
counting_ptr &	operator= (Type *ptr)
	assignment to pointer: dereference current and acquire reference to new ptr. More...
bool	operator== (const counting_ptr &other_ptr) const
	test equality of only the pointer values. More...
void	swap (counting_ptr &b)
	swap enclosed object with another counting pointer (no reference counts need change) More...
void	unify ()
	make and refer a copy if the original object was shared. More...
bool	unique () const
	if the object is referred by this counting_ptr only More...
bool	valid () const
	test for a non-NULL pointer More...

Protected Member Functions
void	dec_reference ()
	decrement reference counter of current object and maybe delete it. More...
void	inc_reference ()
	increment reference counter for current object. More...
void	inc_reference (Type *o)
	increment reference counter of other object. More...

Private Attributes
Type *	m_ptr
	the pointer to the currently referenced object. More...

Member Typedef Documentation

template<class Type>

typedef Type stxxl::counting_ptr< Type >::element_type

contained type.

Definition at line 52 of file counting_ptr.h.

Constructor & Destructor Documentation

template<class Type>

stxxl::counting_ptr< Type >::counting_ptr ( )

inline

default constructor: contains a NULL pointer.

Definition at line 73 of file counting_ptr.h.

template<class Type>

stxxl::counting_ptr< Type >::counting_ptr ( Type *  ptr )

inline

constructor with pointer: initializes new reference to ptr.

Definition at line 77 of file counting_ptr.h.

template<class Type>

stxxl::counting_ptr< Type >::counting_ptr ( const counting_ptr< Type > &  other_ptr )

inline

copy-constructor: also initializes new reference to ptr.

Definition at line 81 of file counting_ptr.h.

template<class Type>

stxxl::counting_ptr< Type >::~counting_ptr ( )

inline

destructor: decrements reference counter in ptr.

Definition at line 98 of file counting_ptr.h.

Member Function Documentation

template<class Type>

void stxxl::counting_ptr< Type >::dec_reference ( )

inlineprotected

decrement reference counter of current object and maybe delete it.

Definition at line 68 of file counting_ptr.h.

template<class Type>

bool stxxl::counting_ptr< Type >::empty ( ) const

inline

test for a NULL pointer

Definition at line 140 of file counting_ptr.h.

Referenced by stxxl::request_queue_impl_1q::add_request(), stxxl::request_queue_impl_qwqr::add_request(), stxxl::request_queue_impl_1q::cancel_request(), and stxxl::request_queue_impl_qwqr::cancel_request().

template<class Type>

Type* stxxl::counting_ptr< Type >::get ( ) const

inline

return the enclosed pointer.

Definition at line 120 of file counting_ptr.h.

Referenced by stxxl::request_queue_impl_qwqr::add_request(), stxxl::request_queue_impl_qwqr::cancel_request(), stxxl::const_counting_ptr< Type >::operator!=(), stxxl::const_counting_ptr< Type >::operator=(), and stxxl::const_counting_ptr< Type >::operator==().

template<class Type>

void stxxl::counting_ptr< Type >::inc_reference ( )

inlineprotected

increment reference counter for current object.

Definition at line 60 of file counting_ptr.h.

template<class Type>

void stxxl::counting_ptr< Type >::inc_reference ( Type *  o )

inlineprotected

increment reference counter of other object.

Definition at line 64 of file counting_ptr.h.

template<class Type>

stxxl::counting_ptr< Type >::operator bool ( ) const

inline

cast to bool check for a NULL pointer

Definition at line 132 of file counting_ptr.h.

template<class Type>

stxxl::counting_ptr< Type >::operator Type * ( ) const

inline

implicit cast to the enclosed pointer.

Definition at line 116 of file counting_ptr.h.

template<class Type>

bool stxxl::counting_ptr< Type >::operator!= ( const counting_ptr< Type > &  other_ptr ) const

inline

test inequality of only the pointer values.

Definition at line 128 of file counting_ptr.h.

template<class Type>

Type& stxxl::counting_ptr< Type >::operator* ( ) const

inline

return the enclosed object as reference.

Definition at line 102 of file counting_ptr.h.

template<class Type>

Type* stxxl::counting_ptr< Type >::operator-> ( ) const

inline

return the enclosed pointer.

Definition at line 109 of file counting_ptr.h.

template<class Type>

counting_ptr& stxxl::counting_ptr< Type >::operator= ( const counting_ptr< Type > &  other_ptr )

inline

assignment operator: dereference current object and acquire reference on new one.

Definition at line 85 of file counting_ptr.h.

template<class Type>

counting_ptr& stxxl::counting_ptr< Type >::operator= ( Type *  ptr )

inline

assignment to pointer: dereference current and acquire reference to new ptr.

Definition at line 89 of file counting_ptr.h.

template<class Type>

bool stxxl::counting_ptr< Type >::operator== ( const counting_ptr< Type > &  other_ptr ) const

inline

test equality of only the pointer values.

Definition at line 124 of file counting_ptr.h.

template<class Type>

void stxxl::counting_ptr< Type >::swap ( counting_ptr< Type > &  b )

inline

swap enclosed object with another counting pointer (no reference counts need change)

Definition at line 155 of file counting_ptr.h.

Referenced by stxxl::swap().

template<class Type>

void stxxl::counting_ptr< Type >::unify ( )

inline

make and refer a copy if the original object was shared.

Definition at line 148 of file counting_ptr.h.

template<class Type>

bool stxxl::counting_ptr< Type >::unique ( ) const

inline

if the object is referred by this counting_ptr only

Definition at line 144 of file counting_ptr.h.

template<class Type>

bool stxxl::counting_ptr< Type >::valid ( ) const

inline

test for a non-NULL pointer

Definition at line 136 of file counting_ptr.h.

Referenced by stxxl::swappable_block< ValueType, BlockSideLength *BlockSideLength >::clean_sync(), stxxl::block_scheduler< SwappableBlockType >::flush(), and stxxl::block_scheduler_algorithm_offline_lru_prefetching< SwappableBlockType >::schedule_write().

Member Data Documentation

template<class Type>

Type* stxxl::counting_ptr< Type >::m_ptr

private

the pointer to the currently referenced object.

Definition at line 56 of file counting_ptr.h.

Referenced by stxxl::counting_ptr< sorted_runs_data_type >::operator!=(), stxxl::counting_ptr< sorted_runs_data_type >::operator=(), stxxl::counting_ptr< sorted_runs_data_type >::operator==(), and stxxl::counting_ptr< sorted_runs_data_type >::swap().

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

• include/stxxl/bits/common/counting_ptr.h