37 lines
854 B
C
37 lines
854 B
C
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/* ------------------------------------------------------------------------ */
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/* */
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/* CRC-calculation routines. */
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/* */
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/* ------------------------------------------------------------------------ */
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#include "uac_crc.h"
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ULONG crctable[256];
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ULONG rd_crc=0;
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void make_crctable(void) // initializes CRC table
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{
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ULONG r,
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i,
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j;
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for (i = 0; i <= 255; i++)
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{
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for (r = i, j = 8; j; j--)
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r = (r & 1) ? (r >> 1) ^ CRCPOLY : (r >> 1);
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crctable[i] = r;
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}
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}
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// Updates crc from addr till addr+len-1
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//
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ULONG getcrc(ULONG crc, UCHAR * addr, INT len)
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{
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while (len--)
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crc = crctable[(unsigned char) crc ^ (*addr++)] ^ (crc >> 8);
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return (crc);
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}
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