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| /programs/cmm/lib/crc32.h |
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| 0,0 → 1,58 |
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| /* CRC32 function; Author PaulCodeman */ |
| :dword crc32Table = 0; |
| :dword makeCRCTable(void) |
| { |
| dword i = 0; |
| dword c = 0; |
| dword ii = 0; |
| dword crcTable = 0; |
| IF (crc32Table) RETURN 0; |
| crc32Table = malloc(4*256); |
| crcTable = crc32Table; |
| WHILE (i < 256) |
| { |
| c = i; |
| ii = 0; |
| WHILE (ii < 8) |
| { |
| IF (c&1) |
| { |
| c >>= 1; |
| c ^= 0xEDB88320; |
| } |
| ELSE c >>= 1; |
| ii++; |
| } |
| DSDWORD[crcTable] = c; |
| crcTable += 4; |
| i++; |
| } |
| } |
| :dword crc32(dword bytes, length) |
| { |
| dword crc = 0; |
| dword i = 0; |
| byte b = 0; |
| IF (!crc32Table) makeCRCTable(); |
| crc = 0xFFFFFFFF; |
| WHILE (i < length) |
| { |
| b = DSBYTE[bytes]; |
| bytes++; |
| EDX = crc^b; |
| EDX &= 0xFF; |
| EDX <<= 2; |
| EDX += crc32Table; |
| crc >>= 8; |
| crc ^= DSDWORD[EDX]; |
| i++; |
| } |
| RETURN crc ^ 0xFFFFFFFF; |
| } |
| |
| /* EXAMPLE |
| dword str = 0; |
| str = "Kevin van Zonneveld"; |
| crc32(str, strlen(str)); |
| IF (EAX == 1249991249) ExitProcess(); |
| */ |
| Property changes: |
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| Added: svn:executable |
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| +* |
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| \ No newline at end of property |
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