coco
54 lines
1.1 KiB
C++
54 lines
1.1 KiB
C++
// Crc16.cpp: implementation of the Crc16 class.
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//
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//////////////////////////////////////////////////////////////////////
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#include "stdafx.h"
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#include "Crc16.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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// Crc16::Crc16()
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// {
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//
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// }
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//
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// Crc16::~Crc16()
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// {
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//
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// }
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unsigned short Crc16::table[ 256 ];
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int Crc16::initialized = 0;
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Crc16::Crc16( unsigned short 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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int k;
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int crc;
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for ( i = 0 ; i < 256 ; i++ ) {
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k = i << 8;
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crc = 0;
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for ( j = 0 ; j < 8 ; j++ ) {
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if ( ( crc ^ k ) & 0x8000 )
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crc = ( crc << 1 ) ^ 0x1021;
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else
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crc <<= 1;
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k <<= 1;
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}
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table[ i ] = (unsigned short) crc;
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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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} |