//C-  -*- C++ -*-

//C- -------------------------------------------------------------------

//C- DjVuLibre-3.5

//C- Copyright (c) 2002  Leon Bottou and Yann Le Cun.

//C- Copyright (c) 2001  AT&T

//C-

//C- This software is subject to, and may be distributed under, the

//C- GNU General Public License, either Version 2 of the license,

//C- or (at your option) any later version. The license should have

//C- accompanied the software or you may obtain a copy of the license

//C- from the Free Software Foundation at http://www.fsf.org .

//C-

//C- This program is distributed in the hope that it will be useful,

//C- but WITHOUT ANY WARRANTY; without even the implied warranty of

//C- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

//C- GNU General Public License for more details.

//C- 

//C- DjVuLibre-3.5 is derived from the DjVu(r) Reference Library from

//C- Lizardtech Software.  Lizardtech Software has authorized us to

//C- replace the original DjVu(r) Reference Library notice by the following

//C- text (see doc/lizard2002.djvu and doc/lizardtech2007.djvu):

//C-

//C-  ------------------------------------------------------------------

//C- | DjVu (r) Reference Library (v. 3.5)

//C- | Copyright (c) 1999-2001 LizardTech, Inc. All Rights Reserved.

//C- | The DjVu Reference Library is protected by U.S. Pat. No.

//C- | 6,058,214 and patents pending.

//C- |

//C- | This software is subject to, and may be distributed under, the

//C- | GNU General Public License, either Version 2 of the license,

//C- | or (at your option) any later version. The license should have

//C- | accompanied the software or you may obtain a copy of the license

//C- | from the Free Software Foundation at http://www.fsf.org .

//C- |

//C- | The computer code originally released by LizardTech under this

//C- | license and unmodified by other parties is deemed "the LIZARDTECH

//C- | ORIGINAL CODE."  Subject to any third party intellectual property

//C- | claims, LizardTech grants recipient a worldwide, royalty-free, 

//C- | non-exclusive license to make, use, sell, or otherwise dispose of 

//C- | the LIZARDTECH ORIGINAL CODE or of programs derived from the 

//C- | LIZARDTECH ORIGINAL CODE in compliance with the terms of the GNU 

//C- | General Public License.   This grant only confers the right to 

//C- | infringe patent claims underlying the LIZARDTECH ORIGINAL CODE to 

//C- | the extent such infringement is reasonably necessary to enable 

//C- | recipient to make, have made, practice, sell, or otherwise dispose 

//C- | of the LIZARDTECH ORIGINAL CODE (or portions thereof) and not to 

//C- | any greater extent that may be necessary to utilize further 

//C- | modifications or combinations.

//C- |

//C- | The LIZARDTECH ORIGINAL CODE is provided "AS IS" WITHOUT WARRANTY

//C- | OF ANY KIND, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED

//C- | TO ANY WARRANTY OF NON-INFRINGEMENT, OR ANY IMPLIED WARRANTY OF

//C- | MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

//C- +------------------------------------------------------------------

#ifdef HAVE_CONFIG_H

# include "config.h"

#endif

#if NEED_GNUG_PRAGMAS

# pragma implementation

#endif

// - Author: Leon Bottou, 05/1997

// From: Leon Bottou, 1/31/2002

// Class GPBuffer has been added (but not documented) by Lizardtech.

// Our original implementation consisted of multiple classes.

// <http://prdownloads.sourceforge.net/djvu/DjVu2_2b-src.tgz>.

#include <stddef.h>

#include <string.h>

#if PARANOID_DEBUG

# include <assert.h>

#endif

#include "GThreads.h"

#include "GSmartPointer.h"

#include "GException.h"

#ifdef HAVE_NAMESPACES

namespace DJVU {

# ifdef NOT_DEFINED // Just to fool emacs c++ mode

}

#endif

#endif

// ------ GPENABLED

GPEnabled::~GPEnabled()

{

  if (count > 0)

    G_THROW( ERR_MSG("GSmartPointer.suspicious") );

}

void

GPEnabled::destroy()

{

  // Only delete if the counter is still zero.

  // because someone may have rescued the object...

  // If yes, set the counter to -0x7fff to mark 

  // the object as doomed and make sure things

  // will work if the destructor uses a GP...

  if (! atomicCompareAndSwap(&count, 0, -0x7fff))

    delete this;

}

// ------ GPBASE

GPBase&

GPBase::assign (const GPBase &sptr)

{

  GPEnabled *nptr = sptr.ptr;

  if (nptr && atomicIncrement(&nptr->count) <= 0)

    nptr = 0;

  GPEnabled *optr = (GPEnabled*)atomicExchangePointer((void**)&ptr, (void*)nptr);

  if (optr)

    optr->unref();

  return *this;

}

GPBase&

GPBase::assign (GPEnabled *nptr)

{

  if (nptr && atomicIncrement(&nptr->count) <= 0)

    nptr = 0;

  GPEnabled *optr = (GPEnabled*)atomicExchangePointer((void**)&ptr, (void*)nptr);

  if (optr)

    optr->unref();

  return *this;

}

// ------ GPBUFFERBASE

void

GPBufferBase::replace(void *nptr,const size_t n)

{

  resize(0,0);

  ptr=nptr;

  num=n;

}

GPBufferBase::GPBufferBase(void *&xptr,const size_t n,const size_t t) 

  : ptr(xptr), num(n)

{

  if (n)

    xptr = ::operator new(n*t);

  else

    xptr = 0;

}

GPBufferBase::~GPBufferBase()

{

  ::operator delete(ptr);

}

void 

GPBufferBase::swap(GPBufferBase &other)

{

  void * const temp_ptr=ptr;

  ptr=other.ptr;

  other.ptr=temp_ptr;

  const size_t temp_num=num;

  num=other.num;

  other.num=temp_num;

}

void

GPBufferBase::resize(const size_t n, const size_t t)

{

  if(!n && !ptr)

    {

      num=0;

    }

  else

    {

      const size_t s=ptr?(((num

      void *nptr;

      GPBufferBase gnptr(nptr, n, t);

      if(s)

        {

          memcpy(nptr, ptr, s);

        }

      swap(gnptr);

    }

}

void

GPBufferBase::set(const size_t t,const char c)

{

  if(num)

    memset(ptr,c,num*t);

}

#ifdef HAVE_NAMESPACES

}

# ifndef NOT_USING_DJVU_NAMESPACE

using namespace DJVU;

# endif

#endif