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#include "sysconfig.h"
#include "sysdeps.h"
#include "crc32.h"
static uae_u32 crc_table32[256];
static uae_u16 crc_table16[256];
static void make_crc_table (void)
{
uae_u32 c;
uae_u16 w;
unsigned int n, k;
for (n = 0; n < 256; n++) {
c = (uae_u32) n;
w = n << 8;
for (k = 0; k < 8; k++) {
c = (c >> 1) ^ (c & 1 ? 0xedb88320 : 0);
w = (w << 1) ^ ((w & 0x8000) ? 0x1021 : 0);
}
crc_table32[n] = c;
crc_table16[n] = w;
}
}
uae_u32 get_crc32 (const uae_u8 *buf, unsigned int len)
{
uae_u32 crc;
if (!crc_table32[1])
make_crc_table ();
crc = 0xffffffff;
while (len-- > 0)
crc = crc_table32[(crc ^ (*buf++)) & 0xff] ^ (crc >> 8);
return crc ^ 0xffffffff;
}
uae_u16 get_crc16 (const uae_u8 *buf, unsigned int len)
{
uae_u16 crc;
if (!crc_table32[1])
make_crc_table ();
crc = 0xffff;
while (len-- > 0)
crc = (crc << 8) ^ crc_table16[((crc >> 8) ^ (*buf++)) & 0xff];
return crc;
}
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