sc::RefCount Class Reference

The base class for all reference counted objects. More...

#include <ref.h>

Inheritance diagram for sc::RefCount:

sc::Identity sc::CorrelationTable sc::DescribedClass sc::GenPetite4 sc::Int1eCCA sc::Int1eCints sc::Int1eV3 sc::Int2eCCA sc::Int2eCints sc::Int2eV3 sc::KeyVal sc::MOPairIter sc::NonlinearTransform sc::OneBodyDerivInt sc::OneBodyInt sc::OneBodyOneCenterDerivInt sc::OneBodyOneCenterInt sc::PrimPairsCints sc::PsiFile11 sc::PsiInput sc::R12Amplitudes sc::SCMatrixSubblockIter sc::SOBasis sc::ThreadLock sc::TwoBodyDerivInt sc::TwoBodyInt sc::TwoBodyThreeCenterDerivInt sc::TwoBodyThreeCenterInt sc::TwoBodyTwoCenterDerivInt sc::TwoBodyTwoCenterInt List of all members.

Public Member Functions

int lock_ptr () const
 Lock this object.
int unlock_ptr () const
 Unlock this object.
void use_locks (bool inVal)
 start and stop using locks on this object
refcount_t nreference () const
 Return the reference count.
refcount_t reference ()
 Increment the reference count and return the new count.
refcount_t dereference ()
 Decrement the reference count and return the new count.
int managed () const
void unmanage ()
 Turn off the reference counting mechanism for this object.
int managed () const
 Return 1 if the object is managed. Otherwise return 0.

Protected Member Functions

 RefCount (const RefCount &)
RefCountoperator= (const RefCount &)

Detailed Description

The base class for all reference counted objects.

If multiple inheritance is used, RefCount must be virtually inherited from, otherwise references to invalid memory will likely result.

Reference counting information is usually maintained by smart pointer classes Ref, however this mechanism can be supplemented or replaced by directly using the public interface to RefCount.

The unmanage() member is only needed for special cases where memory management must be turned off. For example, if a reference counted object is created on the stack, memory management mechanisms based on reference counting must be prohibited from deleting it. The unmanage() member accomplishes this, but a better solution would be to allocate the object on the heap with new and let a smart pointer manage the memory for the object.

When using a debugger to look at reference counted objects the count is maintained in the _reference_count_ member. However, this member is encoded so that memory overwrites can be sometimes detected. Thus, interpretation of _reference_count_ is not always straightforward.


Member Function Documentation

void sc::RefCount::unmanage (  )  [inline]

Turn off the reference counting mechanism for this object.

The value returned by nreference() will always be 1 after this is called. The ability to unmanage() objects must be turned on at compile time by defining REF_MANAGE. There is a slight performance penalty.


The documentation for this class was generated from the following file:
Generated at Mon Dec 3 23:24:01 2007 for MPQC 2.3.1 using the documentation package Doxygen 1.5.2.