coco
51 lines
1.0 KiB
C++
51 lines
1.0 KiB
C++
// Crc32.cpp: implementation of the Crc32 class.
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//
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//////////////////////////////////////////////////////////////////////
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#include "stdafx.h"
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#include "Crc32.h"
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#ifdef _DEBUG
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#undef THIS_FILE
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static char THIS_FILE[]=__FILE__;
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#define new DEBUG_NEW
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#endif
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//////////////////////////////////////////////////////////////////////
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// Construction/Destruction
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//////////////////////////////////////////////////////////////////////
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// Crc32::Crc32()
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// {
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//
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// }
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//
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// Crc32::~Crc32()
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// {
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//
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// }
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unsigned long Crc32::table[ 256 ];
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int Crc32::initialized = 0;
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Crc32::Crc32( unsigned long init_value )
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{
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if ( !initialized ) {
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int i;
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int j;
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unsigned long coeff;
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for ( i = 0; i < 256 ; i++ ) {
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coeff = i;
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for ( j = 0; j < 8; j++ ) {
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if ( coeff & 1 )
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coeff = ( coeff >> 1 ) ^ 0xEDB88320L;
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else
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coeff >>= 1;
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}
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table[ i ] = coeff;
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}
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initialized = 1;
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}
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crc = init_value;
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} |