forked from KolibriOS/kolibrios
65 lines
1.2 KiB
C++
65 lines
1.2 KiB
C++
#include "kosSyst.h"
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#include "CRC32.h"
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CCRC32::CCRC32()
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{
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Dword i, mask, j, k;
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for ( i=0xEDB8; i >= 0x8320; i-- )
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{
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mask = i;
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for ( j=0; j<8; j++ )
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{
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k = mask;
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mask >>= 1;
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if ( k & 1 )
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{
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mask ^= 0xEDB88320;
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}
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this->table[i & 0xFF] = mask;
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}
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}
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}
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Dword CCRC32::InitCRC32()
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{
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return 0xFFFFFFFF;
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}
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Dword CCRC32::FinalizeCRC32(Dword d)
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{
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return ~d;
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}
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void CCRC32::DoCRC32(Byte *buffer, Dword length, Dword *CRC32value)
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{
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Dword result, i;
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Byte mask;
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result = *CRC32value;
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for ( i=0; i<length; i++ )
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{
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mask = (Byte)( ( result ^ buffer[i] ) & 0xFF );
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result = ( result >>= 8 ) ^ this->table[mask];
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}
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*CRC32value = result;
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}
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Dword CCRC32::GetCRC32(Byte *buffer, Dword length)
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{
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Dword result;
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result = 0xFFFFFFFF;
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this->DoCRC32( buffer, length, &result );
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return ~result;
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}
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