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7d17818cec
specification. Simplify things by removing most of the support for known uncompressed size in most places. There are some miscellaneous changes here and there too. The API of liblzma has got many changes and still some more will be done soon. While most of the code has been updated, some things are not fixed (the command line tool will choke with invalid filter chain, if nothing else). Subblock filter is somewhat broken for now. It will be updated once the encoded format of the Subblock filter has been decided.
56 lines
1.2 KiB
C
56 lines
1.2 KiB
C
///////////////////////////////////////////////////////////////////////////////
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//
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/// \file crc64_init.c
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/// \brief CRC64 table initialization
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//
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// This code is based on various public domain sources.
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// This code has been put into the public domain.
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//
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// This library is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
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//
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///////////////////////////////////////////////////////////////////////////////
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#ifdef HAVE_CONFIG_H
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# include "check.h"
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#endif
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#ifdef WORDS_BIGENDIAN
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# include "../../common/bswap.h"
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#endif
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uint64_t lzma_crc64_table[4][256];
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extern void
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lzma_crc64_init(void)
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{
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static const uint64_t poly64 = UINT64_C(0xC96C5795D7870F42);
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for (size_t s = 0; s < 4; ++s) {
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for (size_t b = 0; b < 256; ++b) {
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uint64_t r = s == 0 ? b : lzma_crc64_table[s - 1][b];
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for (size_t i = 0; i < 8; ++i) {
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if (r & 1)
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r = (r >> 1) ^ poly64;
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else
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r >>= 1;
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}
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lzma_crc64_table[s][b] = r;
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}
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}
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#ifdef WORDS_BIGENDIAN
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for (size_t s = 0; s < 4; ++s)
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for (size_t b = 0; b < 256; ++b)
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lzma_crc64_table[s][b]
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= bswap_64(lzma_crc64_table[s][b]);
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#endif
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return;
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}
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