weak_object_ptr< T >

Implementation of a weak pointer for usage with iobject_ptr and object_ptr. More...

#include <weak_object_ptr.h>

Public Member Functions
constexpr	weak_object_ptr () noexcept
	Default constructor for empty construction.
	~weak_object_ptr () noexcept
	Destructs the weak_object_ptr.
constexpr	weak_object_ptr (std::nullptr_t) noexcept
	Construct the weak_ptr from a nullptr - for empty construction.
	weak_object_ptr (const weak_object_ptr &i_oOther) noexcept
	Copy constructor.
weak_object_ptr &	operator= (weak_object_ptr oOther) noexcept
	Assignment operator.
	weak_object_ptr (weak_object_ptr &&oOther) noexcept
	Move constructor.
template<typename U>
	weak_object_ptr (const iobject_ptr< U > &i_pOther) noexcept
	Copy construction from an iobject_ptr.
template<typename U>
weak_object_ptr &	operator= (const iobject_ptr< U > &i_pOther) noexcept
	Assignment from an iobject_ptr.
template<typename U>
tResult	Reset (const iobject_ptr< U > &i_oOther) noexcept
	Reset this weak_object_ptr<> with the content of another iobject_ptr<>
tResult	Reset (const iobject_ptr< T > &i_oOther) noexcept
	Reset this weak_object_ptr<> with the content of another iobject_ptr<>
void	Reset () noexcept
	Reset to an empty weak_ptr object.
void	Swap (weak_object_ptr &o_oOther) noexcept
	Swap content of *this with o_oOther (only shallow copies are performed!)
object_ptr< T >	Lock () const noexcept
	Create an object_ptr<> from *this weak pointer (thread safe).

Private Attributes
T *	m_pObject
	The managed object.
detail::iobject_ptr_ref< size_type > *	m_pRefer
	Refer to control the weak counting.

Detailed Description

template<typename T>
class adtf::ucom::ant::weak_object_ptr< T >

Implementation of a weak pointer for usage with iobject_ptr and object_ptr.

This weak_ptr<> implementation is almost exactly according to the standard. Some functionality required by the standard has been left out to focus on the main task - weak counting! For a detailed explanation of a weak pointer implementation, C++-11 reference websites may be consulted.

Template Parameters

T	Type of the shared resource the weak reference counting is performed on.

Definition at line 33 of file weak_object_ptr.h.

Constructor & Destructor Documentation

weak_object_ptr() [1/5]

template<typename T>

weak_object_ptr ( )

inlineconstexprnoexcept

Default constructor for empty construction.

Definition at line 66 of file weak_object_ptr.h.

References m_pObject, and m_pRefer.

Referenced by weak_object_ptr(), weak_object_ptr(), operator=(), operator=(), and Swap().

~weak_object_ptr()

template<typename T>

~weak_object_ptr ( )

inlinenoexcept

Destructs the weak_object_ptr.

Does not have any effect on the shared resource. The weak_count is decreased by one.

Definition at line 75 of file weak_object_ptr.h.

References Reset().

weak_object_ptr() [2/5]

template<typename T>

weak_object_ptr ( std::nullptr_t )

inlineconstexprnoexcept

Construct the weak_ptr from a nullptr - for empty construction.

Definition at line 83 of file weak_object_ptr.h.

weak_object_ptr() [3/5]

template<typename T>

weak_object_ptr ( const weak_object_ptr< T > & i_oOther )

inlinenoexcept

Copy constructor.

Does not have any effect on the shared count.

Parameters

[in]

i_oOther

weak_ptr to copy from.

Postcondition

If pointer to the shared object is not nullptr, the weak count of the reference counting object gets increased by one.

Definition at line 94 of file weak_object_ptr.h.

References weak_object_ptr().

weak_object_ptr() [4/5]

template<typename T>

weak_object_ptr ( weak_object_ptr< T > && oOther )

inlinenoexcept

Move constructor.

Parameters

[in]

oOther

weak_object_ptr object to create this from. Will be reset.

Definition at line 117 of file weak_object_ptr.h.

References weak_object_ptr(), and Swap().

weak_object_ptr() [5/5]

template<typename T>

template<typename U>

weak_object_ptr ( const iobject_ptr< U > & i_pOther )

inlinenoexcept

Copy construction from an iobject_ptr.

Does not have any effect on the shared count.

Template Parameters

U	Type of managed resource - must be ucom_cast castable to object of type T

Parameters

[in]

i_pOther

Shared object pointer *this gets created from.

Postcondition

If the object pointer manages a valid shared resource, the weak count gets increased by one.

Definition at line 132 of file weak_object_ptr.h.

Member Function Documentation

Lock()

template<typename T>

object_ptr< T > Lock ( ) const

inlinenoexcept

Create an object_ptr<> from *this weak pointer (thread safe).

Does not have any effect on the weak count.

Postcondition

If the shared count for the managed shared resource is greater than zero, the shared count gets increased by one.

Returns

If the shared resource still exists, an object_ptr<> referencing the shared resource. Empty object_ptr<> otherwise.

Definition at line 218 of file weak_object_ptr.h.

operator=() [1/2]

template<typename T>

template<typename U>

weak_object_ptr & operator= ( const iobject_ptr< U > & i_pOther )

inlinenoexcept

Assignment from an iobject_ptr.

Does not have any effect on the shared count.

Template Parameters

U	Type of managed resource - must be ucom_cast castable to object of type T

Parameters

[in]

i_pOther

Shared object pointer *this gets created from.

Postcondition

If the object pointer manages a valid shared resource, the weak count gets increased by one.

Returns

Reference to *this

Definition at line 147 of file weak_object_ptr.h.

References weak_object_ptr().

operator=() [2/2]

template<typename T>

weak_object_ptr & operator= ( weak_object_ptr< T > oOther )

inlinenoexcept

Assignment operator.

Does not have any effect on the shared count.

Parameters

[in]

oOther

Other weak_object_ptr<> to create this from. Call-by-value is intentional to make use of the copy-swap-idiom and the copy elision.

Postcondition

If pointer to the shared object is not nullptr, the weak count of the reference counting object gets increased by one.

Returns

Reference to *this.

Definition at line 107 of file weak_object_ptr.h.

References weak_object_ptr(), and Swap().

Reset() [1/3]

template<typename T>

void Reset ( )

inlinenoexcept

Reset to an empty weak_ptr object.

Postcondition

The weak count on any previously referenced shared resource gets decreased by one.

Returns

Nothing

Definition at line 188 of file weak_object_ptr.h.

References m_pObject, and m_pRefer.

Referenced by ~weak_object_ptr().

Reset() [2/3]

template<typename T>

tResult Reset ( const iobject_ptr< T > & i_oOther )

inlinenoexcept

Reset this weak_object_ptr<> with the content of another iobject_ptr<>

Parameters

[in]

i_oOther

Contains the shared object to reset this type with

Postcondition

Weak count of previously held shared resource is decreased by one. If i_oOther manages a valid shared resource, the weak count gets increased by one for this resource

Return values

ERR_NOERROR

Everything went fine

Definition at line 177 of file weak_object_ptr.h.

Reset() [3/3]

template<typename T>

template<typename U>

tResult Reset ( const iobject_ptr< U > & i_oOther )

inlinenoexcept

Reset this weak_object_ptr<> with the content of another iobject_ptr<>

Parameters

[in]

i_oOther

Contains the shared object to reset this type with

Postcondition

Weak count of previously held shared resource is decreased by one. If i_oOther manages a valid shared resource, the weak count gets increased by one for this resource

Return values

ERR_NOERROR	Everything went fine
ERR_NO_INTERFACE	Managed resource owned by i_oOther does not expose interface type T. *this is reset to nullptr

Definition at line 164 of file weak_object_ptr.h.

References m_pObject.

Swap()

template<typename T>

void Swap ( weak_object_ptr< T > & o_oOther )

inlinenoexcept

Swap content of *this with o_oOther (only shallow copies are performed!)

Parameters

[in,out]

o_oOther

Other object_ptr object whose content is swapped with *this.

Returns

Nothing

Definition at line 203 of file weak_object_ptr.h.

References weak_object_ptr(), m_pObject, and m_pRefer.

Referenced by weak_object_ptr(), and operator=().

Member Data Documentation

m_pObject

template<typename T>

T* m_pObject

private

The managed object.

Definition at line 224 of file weak_object_ptr.h.

Referenced by weak_object_ptr(), Reset(), Reset(), and Swap().

m_pRefer

template<typename T>

detail::iobject_ptr_ref<size_type>* m_pRefer

private

Refer to control the weak counting.

Definition at line 225 of file weak_object_ptr.h.

Referenced by weak_object_ptr(), Reset(), and Swap().