FasTC/Core/include/ReferenceCounter.h

/* FasTC
 * Copyright (c) 2012 University of North Carolina at Chapel Hill. All rights reserved.
 *
 * Permission to use, copy, modify, and distribute this software and its documentation for educational, 
 * research, and non-profit purposes, without fee, and without a written agreement is hereby granted, 
 * provided that the above copyright notice, this paragraph, and the following four paragraphs appear 
 * in all copies.
 *
 * Permission to incorporate this software into commercial products may be obtained by contacting the 
 * authors or the Office of Technology Development at the University of North Carolina at Chapel Hill <otd@unc.edu>.
 *
 * This software program and documentation are copyrighted by the University of North Carolina at Chapel Hill. 
 * The software program and documentation are supplied "as is," without any accompanying services from the 
 * University of North Carolina at Chapel Hill or the authors. The University of North Carolina at Chapel Hill 
 * and the authors do not warrant that the operation of the program will be uninterrupted or error-free. The 
 * end-user understands that the program was developed for research purposes and is advised not to rely 
 * exclusively on the program for any reason.
 *
 * IN NO EVENT SHALL THE UNIVERSITY OF NORTH CAROLINA AT CHAPEL HILL OR THE AUTHORS BE LIABLE TO ANY PARTY FOR 
 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, INCLUDING LOST PROFITS, ARISING OUT OF THE 
 * USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF THE UNIVERSITY OF NORTH CAROLINA AT CHAPEL HILL OR THE 
 * AUTHORS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * THE UNIVERSITY OF NORTH CAROLINA AT CHAPEL HILL AND THE AUTHORS SPECIFICALLY DISCLAIM ANY WARRANTIES, INCLUDING, 
 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE AND ANY 
 * STATUTORY WARRANTY OF NON-INFRINGEMENT. THE SOFTWARE PROVIDED HEREUNDER IS ON AN "AS IS" BASIS, AND THE UNIVERSITY 
 * OF NORTH CAROLINA AT CHAPEL HILL AND THE AUTHORS HAVE NO OBLIGATIONS TO PROVIDE MAINTENANCE, SUPPORT, UPDATES, 
 * ENHANCEMENTS, OR MODIFICATIONS.
 *
 * Please send all BUG REPORTS to <pavel@cs.unc.edu>.
 *
 * The authors may be contacted via:
 *
 * Pavel Krajcevski
 * Dept of Computer Science
 * 201 S Columbia St
 * Frederick P. Brooks, Jr. Computer Science Bldg
 * Chapel Hill, NC 27599-3175
 * USA
 * 
 * <http://gamma.cs.unc.edu/FasTC/>
 */

#ifndef __REFERENCE_COUNTER_H__
#define __REFERENCE_COUNTER_H__

#include "TexCompTypes.h"

class ReferenceCounter {
 public:
 ReferenceCounter() : m_ReferenceCount( new uint32 ) { 
    *m_ReferenceCount = 1;
  }
 ReferenceCounter(const ReferenceCounter &other) 
   : m_ReferenceCount(other.m_ReferenceCount) { 
    IncRefCount();
  }

  ReferenceCounter &operator=(const ReferenceCounter &other) {
    DecRefCount();
    m_ReferenceCount = other.m_ReferenceCount;
    IncRefCount();
  }

  uint32 GetRefCount() const { 
    if(m_ReferenceCount)
      return *m_ReferenceCount; 
    else
      return 0;
  }

  void DecRefCount() { 
    if(!m_ReferenceCount) return;

    (*m_ReferenceCount)--; 

    if(*m_ReferenceCount == 0) {
      delete m_ReferenceCount;
      m_ReferenceCount = 0;
    }
  }
  
  void IncRefCount() { 
    if(!m_ReferenceCount) return;
    (*m_ReferenceCount)++; 
  }

 private:
  uint32 *m_ReferenceCount;
};

#endif // __REFERENCE_COUNTER_H__