MemCore::ReferenceCount Class Reference

Base class for thread-safe reference counting. More...

#include <elementary/memcore/ReferenceCount.hpp>

Inheritance diagram for MemCore::ReferenceCount:

Public Member Functions
bool	canIncrementStrongRefsEvenMore () const noexcept
	The "extreme unction" state is when a pointer is determined to die sure, and this state is set by the suicide() function.
refcount_t	get_pointers () const noexcept
	Return the weak reference count, i.e.
refcount_t	get_refs () const noexcept
	Return the strong reference count, i.e.
refcount_t	weak_refcount () const noexcept
	Return the weak reference count, i.e.

Static Public Attributes
static constexpr refcount_t	dead_object_refcount = -111L
	Some unrealistically large value that is used during premature destruction of objects to indicate that they are still alive even though they will be killed soon after.
static constexpr refcount_t	max_object_refcount = 0x39000000L
	Maximum value that a reference count can reach before it overflows.
static constexpr refcount_t	null_referencer = -222L
	Magic number to indicate that a reference refers to a non-existent reference, i.e.

Protected Member Functions
	ReferenceCount () noexcept
	Initialize reference counts to zero.

Protected Attributes
interlocked_t	strong_refs
	Strong references.
interlocked_t	weak_refs
	Weak references.

Detailed Description

Base class for thread-safe reference counting.

Member Function Documentation

canIncrementStrongRefsEvenMore()

bool MemCore::ReferenceCount::canIncrementStrongRefsEvenMore ( ) const

inlinenoexcept

The "extreme unction" state is when a pointer is determined to die sure, and this state is set by the suicide() function.

In that state a reference pointer can still be incremented and decremented, but it is prone to die soonish.

get_pointers()

refcount_t MemCore::ReferenceCount::get_pointers ( ) const

inlinenoexcept

Return the weak reference count, i.e.

how many pointers refer to this object.

get_refs()

refcount_t MemCore::ReferenceCount::get_refs ( ) const

inlinenoexcept

Return the strong reference count, i.e.

how many object keep this object alive.

weak_refcount()

refcount_t MemCore::ReferenceCount::weak_refcount ( ) const

inlinenoexcept

Return the weak reference count, i.e.

how many pointers refer to this object.

Member Data Documentation

dead_object_refcount

constexpr refcount_t MemCore::ReferenceCount::dead_object_refcount = -111L

staticconstexpr

Some unrealistically large value that is used during premature destruction of objects to indicate that they are still alive even though they will be killed soon after.

Objects with such a strong reference count value pretty much dead. Magic number to indicate that a reference refers to an object that has already died.

max_object_refcount

constexpr refcount_t MemCore::ReferenceCount::max_object_refcount = 0x39000000L

staticconstexpr

Maximum value that a reference count can reach before it overflows.

Theoretically, this value is like the max number of bits, but here we set it to some smaller, arbitrarily chosen value for debugging purposes. It should still never be reached.

null_referencer

constexpr refcount_t MemCore::ReferenceCount::null_referencer = -222L

staticconstexpr

Magic number to indicate that a reference refers to a non-existent reference, i.e.

the weakptr does not have a control block to oeprate on.

Referenced by MemCore::DynPtr< ObjectBase, ObjectBase >::strong_refs(), and MemCore::DynPtr< ObjectBase, ObjectBase >::weak_refs().