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// SPDX-License-Identifier: 0BSD
///////////////////////////////////////////////////////////////////////////////
//
/// \file crc64_tablegen.c
/// \brief Generate crc64_table_le.h and crc64_table_be.h
///
/// Compiling: gcc -std=c99 -o crc64_tablegen crc64_tablegen.c
/// Add -DWORDS_BIGENDIAN to generate big endian table.
//
// Author: Lasse Collin
//
///////////////////////////////////////////////////////////////////////////////
#include <stdio.h>
#include "../../common/tuklib_integer.h"
static uint64_t crc64_table[4][256];
extern void
init_crc64_table(void)
{
static const uint64_t poly64 = UINT64_C(0xC96C5795D7870F42);
for (size_t s = 0; s < 4; ++s) {
for (size_t b = 0; b < 256; ++b) {
uint64_t r = s == 0 ? b : crc64_table[s - 1][b];
for (size_t i = 0; i < 8; ++i) {
if (r & 1)
r = (r >> 1) ^ poly64;
else
r >>= 1;
}
crc64_table[s][b] = r;
}
}
#ifdef WORDS_BIGENDIAN
for (size_t s = 0; s < 4; ++s)
for (size_t b = 0; b < 256; ++b)
crc64_table[s][b] = byteswap64(crc64_table[s][b]);
#endif
return;
}
static void
print_crc64_table(void)
{
// Split the SPDX string so that it won't accidentally match
// when tools search for the string.
printf("// SPDX" "-License-Identifier" ": 0BSD\n\n"
"// This file has been generated by crc64_tablegen.c.\n\n"
"const uint64_t lzma_crc64_table[4][256] = {\n\t{");
for (size_t s = 0; s < 4; ++s) {
for (size_t b = 0; b < 256; ++b) {
if ((b % 2) == 0)
printf("\n\t\t");
printf("UINT64_C(0x%016" PRIX64 ")",
crc64_table[s][b]);
if (b != 255)
printf(",%s", (b+1) % 2 == 0 ? "" : " ");
}
if (s == 3)
printf("\n\t}\n};\n");
else
printf("\n\t}, {");
}
return;
}
int
main(void)
{
init_crc64_table();
print_crc64_table();
return 0;
}
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