E:/Projetos_Primeiro_Semestre_2012/TerraView/terralib/src/terralib/kernel/TeDecoderMemoryMap.h

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/************************************************************************************
TerraLib - a library for developing GIS applications.
Copyright � 2001-2007 INPE and Tecgraf/PUC-Rio.

This code is part of the TerraLib library.
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.

You should have received a copy of the GNU Lesser General Public
License along with this library.

The authors reassure the license terms regarding the warranties.
They specifically disclaim any warranties, including, but not limited to,
the implied warranties of merchantability and fitness for a particular purpose.
The library provided hereunder is on an "as is" basis, and the authors have no
obligation to provide maintenance, support, updates, enhancements, or modifications.
In no event shall INPE and Tecgraf / PUC-Rio be held liable to any party for direct,
indirect, special, incidental, or consequential damages arising out of the use
of this library and its documentation.
*************************************************************************************/
#ifndef  __TERRALIB_INTERNAL_DECODERMEMORYMAP_H
#define  __TERRALIB_INTERNAL_DECODERMEMORYMAP_H

#include "TeDecoder.h"

#ifdef WIN32
#include <windows.h>
#include <winbase.h>
#else
#include <sys/mman.h>
#endif

 
/*
           Due to limits set by the operating system, the maximum amount of data you can map 
           with a single instance of a memory map is 2^31 - 1 (or 2 GB).
*/
class TL_DLL TeDecoderMemoryMap : public TeDecoder
{
public:
           TeDecoderMemoryMap ( const TeRasterParams& );

           ~TeDecoderMemoryMap ();

           bool setElement (int col,int lin, double val, int band=0);

           bool getElement (int col,int lin, double &val,int band=0);

           virtual void init();

           virtual bool clear();

private:
           long       dataInitPos_;
#ifdef WIN32
// Windows support to file memory mapping
           HANDLE  m_hFile;                            // Handle to file we're currently zapping
           HANDLE     m_hMapping;                                 // Handle to memory-mapping of that file
           LPVOID  m_lpszFile;                         // Pointer to view of file mapped to memory
           DWORD      m_dwSize;
#else
// Linux support to file memory mapping
           int        m_hFile;                         //(fd) Handle to file we're currently zapping
           void*      m_lpszFile;                                 // Pointer to view of file mapped to memory
           off_t      m_dwSize;
#endif
};

class TL_DLL TeDecoderMemoryMapFactory : public TeDecoderFactory
{
public:

           TeDecoderMemoryMapFactory(const string& name);

           virtual TeDecoder* build (const TeRasterParams& arg)
           {  return new TeDecoderMemoryMap(arg); }
};
#endif