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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/common/stream_flags_decoder.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/common/stream_flags_decoder.c')
-rw-r--r-- | contrib/xz/src/liblzma/common/stream_flags_decoder.c | 82 |
1 files changed, 82 insertions, 0 deletions
diff --git a/contrib/xz/src/liblzma/common/stream_flags_decoder.c b/contrib/xz/src/liblzma/common/stream_flags_decoder.c new file mode 100644 index 0000000..1bc2f97 --- /dev/null +++ b/contrib/xz/src/liblzma/common/stream_flags_decoder.c @@ -0,0 +1,82 @@ +/////////////////////////////////////////////////////////////////////////////// +// +/// \file stream_flags_decoder.c +/// \brief Decodes Stream Header and Stream Footer from .xz files +// +// Author: Lasse Collin +// +// This file has been put into the public domain. +// You can do whatever you want with this file. +// +/////////////////////////////////////////////////////////////////////////////// + +#include "stream_flags_common.h" + + +static bool +stream_flags_decode(lzma_stream_flags *options, const uint8_t *in) +{ + // Reserved bits must be unset. + if (in[0] != 0x00 || (in[1] & 0xF0)) + return true; + + options->version = 0; + options->check = in[1] & 0x0F; + + return false; +} + + +extern LZMA_API(lzma_ret) +lzma_stream_header_decode(lzma_stream_flags *options, const uint8_t *in) +{ + // Magic + if (memcmp(in, lzma_header_magic, sizeof(lzma_header_magic)) != 0) + return LZMA_FORMAT_ERROR; + + // Verify the CRC32 so we can distinguish between corrupt + // and unsupported files. + const uint32_t crc = lzma_crc32(in + sizeof(lzma_header_magic), + LZMA_STREAM_FLAGS_SIZE, 0); + if (crc != unaligned_read32le(in + sizeof(lzma_header_magic) + + LZMA_STREAM_FLAGS_SIZE)) + return LZMA_DATA_ERROR; + + // Stream Flags + if (stream_flags_decode(options, in + sizeof(lzma_header_magic))) + return LZMA_OPTIONS_ERROR; + + // Set Backward Size to indicate unknown value. That way + // lzma_stream_flags_compare() can be used to compare Stream Header + // and Stream Footer while keeping it useful also for comparing + // two Stream Footers. + options->backward_size = LZMA_VLI_UNKNOWN; + + return LZMA_OK; +} + + +extern LZMA_API(lzma_ret) +lzma_stream_footer_decode(lzma_stream_flags *options, const uint8_t *in) +{ + // Magic + if (memcmp(in + sizeof(uint32_t) * 2 + LZMA_STREAM_FLAGS_SIZE, + lzma_footer_magic, sizeof(lzma_footer_magic)) != 0) + return LZMA_FORMAT_ERROR; + + // CRC32 + const uint32_t crc = lzma_crc32(in + sizeof(uint32_t), + sizeof(uint32_t) + LZMA_STREAM_FLAGS_SIZE, 0); + if (crc != unaligned_read32le(in)) + return LZMA_DATA_ERROR; + + // Stream Flags + if (stream_flags_decode(options, in + sizeof(uint32_t) * 2)) + return LZMA_OPTIONS_ERROR; + + // Backward Size + options->backward_size = unaligned_read32le(in + sizeof(uint32_t)); + options->backward_size = (options->backward_size + 1) * 4; + + return LZMA_OK; +} |