fad81ed299
git-svn-id: svn://svn.h5l.se/heimdal/trunk/heimdal@1107 ec53bebd-3082-4978-b11e-865c3cabbd6b
34 lines
518 B
C
34 lines
518 B
C
#include <stdio.h>
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#include "crc.h"
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static u_long table[256];
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void
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crc_init_table( )
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{
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unsigned long crc, poly;
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int i, j;
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poly = 0xEDB88320L;
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for (i = 0; i < 256; i++) {
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crc = i;
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for (j = 8; j > 0; j--) {
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if (crc & 1) {
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crc = (crc >> 1) ^ poly;
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} else {
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crc >>= 1;
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}
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}
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table[i] = crc;
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}
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}
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u_long
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crc_update (char *p, size_t len, u_long res)
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{
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res ^= 0xFFFFFFFF;
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while (len--)
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res = table[(res ^ *p++) & 0xFF] ^ (res >> 8);
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return res & 0xFFFFFFFF;
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}
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