60 lines
1.1 KiB
C
60 lines
1.1 KiB
C
/*++
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Copyright (C) 1997-2001 Microsoft Corporation
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Module Name:
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CRC32.H
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Abstract:
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Standard CRC-32 implementation
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History:
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raymcc 07-Jul-97 Createada
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--*/
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#ifndef _CRC_H_
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#define _CRC_H_
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#define STARTING_CRC32_VALUE 0xFFFFFFFF
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DWORD UpdateCRC32(
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LPBYTE pSrc, // Points to buffer
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int nBytes, // Number of bytes to compute
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DWORD dwOldCrc // Must be STARTING_CRC_VALUE (0xFFFFFFFF)
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// if no previous CRC, otherwise this is the
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// CRC of the previous cycle.
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);
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#define FINALIZE_CRC32(x) (x=~x)
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/*
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The CRC holding value must be preinitialized to STARTING_CRC32_VALUE
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UpdateCRC32() may be called as many times as necessary on a single buffer.
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When computing the CRC32
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The final value must be post-processed using the FINALIZE_CRC32() macro.
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Example:
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void main()
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{
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BYTE Data[] = { 1, 2, 3 };
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DWORD dwCRC = STARTING_CRC32_VALUE;
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dwCRC = UpdateCRC32(Data, 3, dwCRC);
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FINALIZE_CRC32(dwCRC);
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printf("CRC32 = 0x%X\n", dwCRC);
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}
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*/
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#endif
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