nel/3rdparty/seven_zip/Lzma86.h

   1 /* Lzma86.h -- LZMA + x86 (BCJ) Filter
   2 2013-01-18 : Igor Pavlov : Public domain */
   3
   4 #ifndef __LZMA86_H
   5 #define __LZMA86_H
   6
   7 #include "7zTypes.h"
   8
   9 EXTERN_C_BEGIN
  10
  11 #define LZMA86_SIZE_OFFSET (1 + 5)
  12 #define LZMA86_HEADER_SIZE (LZMA86_SIZE_OFFSET + 8)
  13
  14 /*
  15 It's an example for LZMA + x86 Filter use.
  16 You can use .lzma86 extension, if you write that stream to file.
  17 .lzma86 header adds one additional byte to standard .lzma header.
  18 .lzma86 header (14 bytes):
  19   Offset Size  Description
  20     0     1    = 0 - no filter, pure LZMA
  21                = 1 - x86 filter + LZMA
  22     1     1    lc, lp and pb in encoded form
  23     2     4    dictSize (little endian)
  24     6     8    uncompressed size (little endian)
  25
  26
  27 Lzma86_Encode
  28 -------------
  29 level - compression level: 0 <= level <= 9, the default value for "level" is 5.
  30
  31 dictSize - The dictionary size in bytes. The maximum value is
  32         128 MB = (1 << 27) bytes for 32-bit version
  33           1 GB = (1 << 30) bytes for 64-bit version
  34      The default value is 16 MB = (1 << 24) bytes, for level = 5.
  35      It's recommended to use the dictionary that is larger than 4 KB and
  36      that can be calculated as (1 << N) or (3 << N) sizes.
  37      For better compression ratio dictSize must be >= inSize.
  38
  39 filterMode:
  40     SZ_FILTER_NO   - no Filter
  41     SZ_FILTER_YES  - x86 Filter
  42     SZ_FILTER_AUTO - it tries both alternatives to select best.
  43               Encoder will use 2 or 3 passes:
  44               2 passes when FILTER_NO provides better compression.
  45               3 passes when FILTER_YES provides better compression.
  46
  47 Lzma86Encode allocates Data with MyAlloc functions.
  48 RAM Requirements for compressing:
  49   RamSize = dictionarySize * 11.5 + 6MB + FilterBlockSize
  50       filterMode     FilterBlockSize
  51      SZ_FILTER_NO         0
  52      SZ_FILTER_YES      inSize
  53      SZ_FILTER_AUTO     inSize
  54
  55
  56 Return code:
  57   SZ_OK               - OK
  58   SZ_ERROR_MEM        - Memory allocation error
  59   SZ_ERROR_PARAM      - Incorrect paramater
  60   SZ_ERROR_OUTPUT_EOF - output buffer overflow
  61   SZ_ERROR_THREAD     - errors in multithreading functions (only for Mt version)
  62 */
  63
  64 enum ESzFilterMode
  65 {
  66   SZ_FILTER_NO,
  67   SZ_FILTER_YES,
  68   SZ_FILTER_AUTO
  69 };
  70
  71 SRes Lzma86_Encode(Byte *dest, size_t *destLen, const Byte *src, size_t srcLen,
  72     int level, UInt32 dictSize, int filterMode);
  73
  74
  75 /*
  76 Lzma86_GetUnpackSize:
  77   In:
  78     src      - input data
  79     srcLen   - input data size
  80   Out:
  81     unpackSize - size of uncompressed stream
  82   Return code:
  83     SZ_OK               - OK
  84     SZ_ERROR_INPUT_EOF  - Error in headers
  85 */
  86
  87 SRes Lzma86_GetUnpackSize(const Byte *src, SizeT srcLen, UInt64 *unpackSize);
  88
  89 /*
  90 Lzma86_Decode:
  91   In:
  92     dest     - output data
  93     destLen  - output data size
  94     src      - input data
  95     srcLen   - input data size
  96   Out:
  97     destLen  - processed output size
  98     srcLen   - processed input size
  99   Return code:
 100     SZ_OK           - OK
 101     SZ_ERROR_DATA  - Data error
 102     SZ_ERROR_MEM   - Memory allocation error
 103     SZ_ERROR_UNSUPPORTED - unsupported file
 104     SZ_ERROR_INPUT_EOF - it needs more bytes in input buffer
 105 */
 106
 107 SRes Lzma86_Decode(Byte *dest, SizeT *destLen, const Byte *src, SizeT *srcLen);
 108
 109 EXTERN_C_END
 110
 111 #endif