Smart Pointers and other Pointer classes

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Because copy has different meaning with different classes, there are several pointer
classes here.

  • Smart pointers classes. Replace the now
    obsolete CWizPtr, BaseMultiRefPtr, and MultiRefPtr.(I don’t remove them for convenience
    only). No plain C/C++ pointers again!
    File SmartPointers.h defines the following classes:

    • CWizSmartPtr – trivial base class for all others;
    • CWizSafePtr – smart pointer class which basic garbage collections (i.e. knows to
      delete the pointer in destructor). From here and later every pointer class must hold
      a pointer allocated from heap only! Copy operator attaches the object to the
      pointer and then detaches it from previous pointer – "pessimistic shadow copy".
    • CWizSafeArray – simple array of objects.
    • CWizDuplPtr – implements deep copy semantics for copy constructor/operator.
      Requires from an object to have a copy constructor. No polymorphism.
    • CWizClonePtr – implements deep copy semantics for copy constructor/operator, with
      support for polymorphism in pointed object. Requires from an object to have a Clone()
      function. In the case of polymorphism a Clone() function must be virtual function
      returning pointer to the root of hierarchy.
      An example:

      class A
      {
      A(const A& a);
      virtual A* Clone() const { return new A(*this); }
      };

      class B
      {
      B(const B& a);
      virtual A* Clone() const { return new B(*this); }
      };

    • CWizBaseMultiRefPtr – Multiply pointer classes with reference counting and
      polymorphism.
      Class implements basic machinery of reference counting, but doesn’t implement a counter.
      Class CWizMultiRefPtr uses int as counter (the simplest solution).
      Implement garbage collection with reference counting, shadow copy, polymorphism.
    • CWizCounterMultiRefPtr – optimized Multiply pointer classes with reference
      counting
      and polymorphism. Differs from CWizBaseMultiRefPtr in implementing reference
      counting,
      which shifted to the managed class itself. It minimizes memory fragmentation, but requires
      access to the managed classes, which is not always possible.
       

    File SmartPointersSerialize.h defines StoreSmartPtr()
    and LoadSmartPtr() functions for serializing to/from MFC CArchive.
    File SmartPointerArrays.h defines arrays of smart
    pointers. All arrays are derived from CArray of MFC.
    File SmartPointerArraysSerialize.h defines
    template function SerializeArray() for serializing to/from MFC CArchive.
    File SmartPointerArraysSort.h defines template
    function SerializeArray() for serializing to/from MFC CArchive.
    File SerializeVersion.h defines function
    SortSmartPrtArray().

  • Multiply pointer class with reference counting CWizMultiPtr.
    Designed to hold objects of one class (no polymorphism). Several pointers can point to the
    same object; the object deleted when destroying the last pointer to it. By the nature uses
    shallow copy.
    File MULTIPTR.H .
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