Replace GeoPVLink & GeoPVConstLink with a GeoSmartLink pointer

Hi everybody,

in atlas/athena!67229 (merged), @tsulaia told me that the GeoPVLink and the GeoPVConstLink are not incrementing / decrementing the reference counters of the PhysVols that they hold. In fact, they're nothing else than a wrapper. That's quite surprising to me and I think that this beheviour should change. In this MR, I've replaced the two classes by the GeoSmartLink class -- Improvements to the name are more than welcome -- which takes over the reference counting and also which can transparently casted into the bare pointers. The reference count updates will probably introduce some overhead to the overall code. How much I don't know.. How to test? I don't know neither.

Tagging: @rbianchi, @boudreau, @nstyles, @mbandier

GeoModelCore/GeoModelKernel/GeoModelKernel/ConstLink.h

-/*
-  Copyright (C) 2002-2017 CERN for the benefit of the ATLAS collaboration
-*/
-
-#ifndef GEOMODELKERNEL_CONSTLINK_H
-#define GEOMODELKERNEL_CONSTLINK_H
-
-/**
- * @class ConstLink
- * 
- * @brief Smart links to reference-counted pointers.  Used in this
- *      package for calorimeter cells
- **	Template Smart Pointer Class.  This reference counted
- *	link allocates on demand. It audits the total pointer
- *	count and collects the garbage when nobody's looking.
- */
-
-template <class T>
-class ConstLink 
-{
-  public:
-  
-
-  /**
-   * @brief Constructor
-   */
-  ConstLink();
-  
-  /**
-   * @brief Copy Constructor
-   */
-  ConstLink(const ConstLink< T > &right);
-  
-  /**
-   * @brief Constructor
-   */
-  ConstLink (const T *target);
-  
-  /**
-   * @brief Destructor 
-   */
-  virtual ~ConstLink();
-  
-  /**
-   * @brief Assignment
-   */
-  ConstLink< T > & operator=(const ConstLink< T > &right);
-  
-  /**
-   * @brief Equality
-   */
-  int operator==(const ConstLink< T > &right) const;
-  
-  /**
-   * @brief Inequality
-   */
-  int operator!=(const ConstLink< T > &right) const;
-  
-  
-  /**
-   * @brief Relational operator
-   */
-  int operator<(const ConstLink< T > &right) const;
-  
-  /**
-   * @brief Relational operator
-   */
-  int operator>(const ConstLink< T > &right) const;
-  
-  /**
-   * @brief Relational operator
-   */
-  int operator<=(const ConstLink< T > &right) const;
-  
-  /**
-   * @brief Relational operator
-   */
-  int operator>=(const ConstLink< T > &right) const;
-  
-  
-  
-  /**
-   *     @brief Dereference:  (*t).method();
-   */
-  virtual const T & operator * () const;
-  
-  /**
-   *     @brief Dereference: t->method()
-   */
-  virtual const T * operator -> () const;
-  
-  /**
-   *      @brief Check pointer validity:  if (t) {...}
-   */
-  operator bool () const;
-  
-
-
-  private: 
-  /**
-   * @brief Raw pointer to reference counted object.
-   */ 
-  mutable T *m_ptr;
-};
-
-
-
-template <class T>
-inline ConstLink<T>::ConstLink()
-  :m_ptr(nullptr)
-{
-}
-
-template <class T>
-inline ConstLink<T>::ConstLink(const ConstLink<T> &right)
-  :m_ptr(right.m_ptr)
-{
-  if (m_ptr) m_ptr->ref();
-}
-
-template <class T>
-inline ConstLink<T>::ConstLink (const T *target)
-  :m_ptr(const_cast<T *> (target))
-{
-  if (target) target->ref();
-}
-
-
-template <class T>
-inline ConstLink<T>::~ConstLink()
-{
-  if (m_ptr) m_ptr->unref();
-}
-
-
-template <class T>
-inline ConstLink<T> & ConstLink<T>::operator=(const ConstLink<T> &right)
-{
-  if (this!=&right) {
-    if (m_ptr) m_ptr->unref();
-    m_ptr = right.m_ptr;
-    if (m_ptr) m_ptr->ref();
-  }
-  return *this;
-}
-
-
-template <class T>
-inline int ConstLink<T>::operator==(const ConstLink<T> &right) const
-{
-  return m_ptr==right.m_ptr;
-}
-
-template <class T>
-inline int ConstLink<T>::operator!=(const ConstLink<T> &right) const
-{
-  return m_ptr!=right.m_ptr;
-}
-
-
-template <class T>
-inline int ConstLink<T>::operator<(const ConstLink<T> &right) const
-{
-  return m_ptr<right.m_ptr;
-}
-
-template <class T>
-inline int ConstLink<T>::operator>(const ConstLink<T> &right) const
-{
-  return m_ptr>right.m_ptr;
-}
-
-template <class T>
-inline int ConstLink<T>::operator<=(const ConstLink<T> &right) const
-{
-  return m_ptr<=right.m_ptr;
-}
-
-template <class T>
-inline int ConstLink<T>::operator>=(const ConstLink<T> &right) const
-{
-  return m_ptr>=right.m_ptr;
-}
-
-
-
-template <class T>
-inline const T & ConstLink<T>::operator * () const
-{
-  return *m_ptr;
-}
-
-template <class T>
-inline const T * ConstLink<T>::operator -> () const
-{
-  return m_ptr;
-}
-
-template <class T>
-inline ConstLink<T>::operator bool () const
-{
-  return m_ptr;
-}
-
-#endif