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author | mm <mm@FreeBSD.org> | 2010-05-10 06:59:50 +0000 |
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committer | mm <mm@FreeBSD.org> | 2010-05-10 06:59:50 +0000 |
commit | 5c358d45429b654efa9c8177ecd370a7965ec1a7 (patch) | |
tree | d2d916954c6a66a3168ee356b5f24da01c2017d6 /contrib/xz/src/liblzma/check/crc64_small.c | |
parent | 3e09decd1986826f54af1a47be97bb87c1220783 (diff) | |
parent | 1008b7c6744a190c5b15aaf8cab1054671e4c7c3 (diff) | |
download | FreeBSD-src-5c358d45429b654efa9c8177ecd370a7965ec1a7.zip FreeBSD-src-5c358d45429b654efa9c8177ecd370a7965ec1a7.tar.gz |
Import of liblzma, xz, xzdec, lzmainfo from vendor branch
Add support for xz and lzma to lesspipe.sh (xzless, lzless)
Bump __FreeBSD_version
Approved by: delphij (mentor)
MFC after: 2 weeks
Diffstat (limited to 'contrib/xz/src/liblzma/check/crc64_small.c')
-rw-r--r-- | contrib/xz/src/liblzma/check/crc64_small.c | 53 |
1 files changed, 53 insertions, 0 deletions
diff --git a/contrib/xz/src/liblzma/check/crc64_small.c b/contrib/xz/src/liblzma/check/crc64_small.c new file mode 100644 index 0000000..55d7231 --- /dev/null +++ b/contrib/xz/src/liblzma/check/crc64_small.c @@ -0,0 +1,53 @@ +/////////////////////////////////////////////////////////////////////////////// +// +/// \file crc64_small.c +/// \brief CRC64 calculation (size-optimized) +// +// Author: Lasse Collin +// +// This file has been put into the public domain. +// You can do whatever you want with this file. +// +/////////////////////////////////////////////////////////////////////////////// + +#include "check.h" + + +static uint64_t crc64_table[256]; + + +static void +crc64_init(void) +{ + static const uint64_t poly64 = UINT64_C(0xC96C5795D7870F42); + + for (size_t b = 0; b < 256; ++b) { + uint64_t r = b; + for (size_t i = 0; i < 8; ++i) { + if (r & 1) + r = (r >> 1) ^ poly64; + else + r >>= 1; + } + + crc64_table[b] = r; + } + + return; +} + + +extern LZMA_API(uint64_t) +lzma_crc64(const uint8_t *buf, size_t size, uint64_t crc) +{ + mythread_once(crc64_init); + + crc = ~crc; + + while (size != 0) { + crc = crc64_table[*buf++ ^ (crc & 0xFF)] ^ (crc >> 8); + --size; + } + + return ~crc; +} |