Core/MemoryMappedFile.h

/*===========================================================================
FILE: 
   MemoryMappedFile.h

DESCRIPTION:
   Declaration of cMemoryMappedFile class

PUBLIC CLASSES AND METHODS:
   cMemoryMappedFile
      The cMemoryMappedFile class provides the ability to read in a file 
      via Linux memory maps

      Note: cMemoryMappedFiles are read only
    
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===========================================================================*/

//---------------------------------------------------------------------------
// Pragmas
//---------------------------------------------------------------------------
#pragma once

/*=========================================================================*/
// Class cMemoryMappedFile
/*=========================================================================*/
class cMemoryMappedFile
{
   public:
      // Constructor (loads file)
      cMemoryMappedFile( LPCSTR pFile );

      // Constructor (loads file from resource)
      cMemoryMappedFile( 
         const char *               pStart,
         const int                  nSize );

      // Destructor
      virtual ~cMemoryMappedFile();

      // (Inline) Get error status
      DWORD GetStatus()
      {
         DWORD stat = mStatus;
         if (mStatus == NO_ERROR)
         {
            if (mpBuffer == 0 || mFileSize == 0)
            {
               // We failed but GetLastError() return NO_ERROR
               stat = ERROR_NO_MORE_ITEMS;
            }
         }

         return stat;
      };

      // (Inline) Return the size of the file (contents)
      ULONG GetSize()
      {
         ULONG sz = 0;
         if (GetStatus() == NO_ERROR)
         {
            sz = mFileSize;
         }

         return sz;
      };

      // (Inline) Return the file contents
      LPVOID GetContents()
      {
         LPVOID pContents = 0;
         if (GetStatus() == NO_ERROR)
         {
            pContents = mpBuffer;
         }

         return pContents;
      };

   protected:
      /* Resource based file? */
      bool mbResourceBased;

      /* File handle */
      int mFile;

      /* File contents*/
      LPVOID mpBuffer;

      /* File size */
      ULONG mFileSize;

      /* Error status */
      DWORD mStatus;
};