CountedConstPtrOrConstPtr.h

#pragma once

#if defined(CountedConstPtrOrConstPtr_RECURSES)
#error Recursive header files inclusion detected in CountedConstPtrOrConstPtr.h
#else // defined(CountedConstPtrOrConstPtr_RECURSES)

#define CountedConstPtrOrConstPtr_RECURSES

#if !defined CountedConstPtrOrConstPtr_h

#define CountedConstPtrOrConstPtr_h

// Inclusions
#include <iostream>
#include "DGtal/base/Common.h"
#include "DGtal/base/CountedPtr.h"
#include "DGtal/base/CountedPtrOrPtr.h"

namespace DGtal
{

  // template class CountedConstPtrOrConstPtr
  template <typename T>
  class CountedConstPtrOrConstPtr
  {
  public:

    // ----------------------- Standard services ------------------------------
  public:

    typedef typename CountedPtr<T>::Counter Counter;

    inline explicit CountedConstPtrOrConstPtr( const T* p = 0, bool isCountedPtr = true )
      : myAny(0), myIsCountedPtr( isCountedPtr )
    { 
      if ( isCountedPtr ) {
        if (p) myAny = static_cast<void*>( new Counter( const_cast<T*>( p ) ) );
      }
      else
        myAny = const_cast<void*>( static_cast<const void*>( p ) );
    }

    ~CountedConstPtrOrConstPtr()
    {
      if ( myIsCountedPtr ) release(); 
    }

    CountedConstPtrOrConstPtr( const CountedPtr<T> & r ) throw()
      : myIsCountedPtr( true )
    { 
      acquire( r.myCounter ); 
    }

    CountedConstPtrOrConstPtr(const CountedConstPtrOrConstPtr& r) throw()
      : myIsCountedPtr( r.myIsCountedPtr )
    { 
      if ( myIsCountedPtr )
        acquire( r.counterPtr() ); 
      else
        myAny = r.myAny;
    }

    CountedConstPtrOrConstPtr(const CountedPtrOrPtr<T>& r) throw()
      : myIsCountedPtr( r.myIsCountedPtr )
    { 
      if ( myIsCountedPtr )
        acquire( r.counterPtr() ); 
      else
        myAny = r.myAny;
    }

    CountedConstPtrOrConstPtr& operator=(const CountedConstPtrOrConstPtr& r)
    {
      if ( this != & r ) {
        if ( myIsCountedPtr ) release();
        myIsCountedPtr = r.myIsCountedPtr;
        if ( r.myIsCountedPtr ) acquire( r.counterPtr() );
        else myAny = r.myAny;
      }
      return *this;
    }

    CountedConstPtrOrConstPtr& operator=(const CountedPtrOrPtr<T>& r)
    {
      if ( myIsCountedPtr ) release();
      myIsCountedPtr = r.myIsCountedPtr;
      if ( r.myIsCountedPtr ) acquire( r.counterPtr() );
      else myAny = r.myAny;
      return *this;
    }

    CountedConstPtrOrConstPtr& operator=(const CountedPtr<T>& r)
    {
      if ( myIsCountedPtr ) release();
      myIsCountedPtr = true;
      acquire( r.myCounter );
      return *this;
    }

    bool isSmart() const
    {
      return myIsCountedPtr;
    }

    bool isSimple() const
    {
      return ! myIsCountedPtr;
    }

    bool operator==( const T* other ) const
    {
      return myIsCountedPtr ? ( myAny ? counterPtr()->ptr : 0 ) == other : ptr() == other;
    }

    bool operator!=( const T* other ) const
    {
      return myIsCountedPtr ? ( myAny ? counterPtr()->ptr : 0 ) != other : ptr() != other;
    }

    const T& operator*()  const throw()
    { 
      // Travis is too slow in Debug mode with this ASSERT.
      ASSERT( isValid() );
      return myIsCountedPtr ? ( * counterPtr()->ptr ) : ( * ptr() ); 
    }

    const T* operator->() const throw()
    { 
      // Travis is too slow in Debug mode with this ASSERT.
      ASSERT( isValid() );
      return myIsCountedPtr ? counterPtr()->ptr : ptr();
    }

    const T* get()        const throw()
    {
      return myIsCountedPtr ? ( myAny ? counterPtr()->ptr : 0 ) : ptr(); 
    }

    bool unique()   const throw()
    {
      return myIsCountedPtr
        ? ( myAny ? counterPtr()->count == 1 : true )
        : true;
    }

    unsigned int count() const
    { 
      return myIsCountedPtr ? counterPtr()->count : 0; 
    }

    inline const T* drop() 
    { // Gives back the pointer without deleting him. Delete only the counter.
      ASSERT( isValid() );
      if ( myIsCountedPtr ) {
        ASSERT( unique() );
        T* tmp = counterPtr()->ptr;
        delete counterPtr();
        myAny = 0; 
        return tmp;
      } else {
        return ptr();
      }
    }

private:

    void* myAny;
    bool myIsCountedPtr;

            
    inline Counter* counterPtr() const
    { 
      // Travis is too slow in Debug mode with this ASSERT.
      ASSERT( myIsCountedPtr );
      return static_cast<Counter*>( myAny ); 
    }

    inline T* ptr() const
    { 
      // Travis is too slow in Debug mode with this ASSERT.
      ASSERT( ! myIsCountedPtr );
      return static_cast<T*>( myAny ); 
    }

    inline void acquire(Counter* c) throw()
    { // increment the count
      // Travis is too slow in Debug mode with this ASSERT.
      ASSERT( myIsCountedPtr );
      myAny = static_cast<void*>( c );
      if (c) ++c->count;
    }

    void release()
    { // decrement the count, delete if it is 0
      // Travis is too slow in Debug mode with this ASSERT.
      ASSERT( myIsCountedPtr );
      if (myAny) {
        Counter * counter = counterPtr();
        if (--counter->count == 0) {
          delete counter->ptr;
          delete counter;
        }
        myAny = 0;
      }
    }


    // ----------------------- Interface --------------------------------------
  public:

    void selfDisplay ( std::ostream & out ) const;

    bool isValid() const;

    // ------------------------- Protected Datas ------------------------------
  private:
    // ------------------------- Private Datas --------------------------------
  private:

    // ------------------------- Hidden services ------------------------------
  protected:


    // ------------------------- Internals ------------------------------------
  private:

  }; // end of class CountedConstPtrOrConstPtr


  template <typename T>
  std::ostream&
  operator<< ( std::ostream & out, const CountedConstPtrOrConstPtr<T> & object );

} // namespace DGtal


// Includes inline functions.
#include "DGtal/base/CountedConstPtrOrConstPtr.ih"

//                                                                           //

#endif // !defined CountedConstPtrOrConstPtr_h

#undef CountedConstPtrOrConstPtr_RECURSES
#endif // else defined(CountedConstPtrOrConstPtr_RECURSES)