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			112 lines
		
	
	
		
			3.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			112 lines
		
	
	
		
			3.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* Lzma86.h -- LZMA + x86 (BCJ) Filter
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| 2013-01-18 : Igor Pavlov : Public domain */
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| 
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| #ifndef __LZMA86_H
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| #define __LZMA86_H
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| 
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| #include "7zTypes.h"
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| 
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| EXTERN_C_BEGIN
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| 
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| #define LZMA86_SIZE_OFFSET (1 + 5)
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| #define LZMA86_HEADER_SIZE (LZMA86_SIZE_OFFSET + 8)
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| 
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| /*
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| It's an example for LZMA + x86 Filter use.
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| You can use .lzma86 extension, if you write that stream to file.
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| .lzma86 header adds one additional byte to standard .lzma header.
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| .lzma86 header (14 bytes):
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|   Offset Size  Description
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|     0     1    = 0 - no filter, pure LZMA
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|                = 1 - x86 filter + LZMA
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|     1     1    lc, lp and pb in encoded form
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|     2     4    dictSize (little endian)
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|     6     8    uncompressed size (little endian)
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| 
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| 
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| Lzma86_Encode
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| -------------
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| level - compression level: 0 <= level <= 9, the default value for "level" is 5.
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| 
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| dictSize - The dictionary size in bytes. The maximum value is
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|         128 MB = (1 << 27) bytes for 32-bit version
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|           1 GB = (1 << 30) bytes for 64-bit version
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|      The default value is 16 MB = (1 << 24) bytes, for level = 5.
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|      It's recommended to use the dictionary that is larger than 4 KB and
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|      that can be calculated as (1 << N) or (3 << N) sizes.
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|      For better compression ratio dictSize must be >= inSize.
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| 
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| filterMode:
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|     SZ_FILTER_NO   - no Filter
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|     SZ_FILTER_YES  - x86 Filter
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|     SZ_FILTER_AUTO - it tries both alternatives to select best.
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|               Encoder will use 2 or 3 passes:
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|               2 passes when FILTER_NO provides better compression.
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|               3 passes when FILTER_YES provides better compression.
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| 
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| Lzma86Encode allocates Data with MyAlloc functions.
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| RAM Requirements for compressing:
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|   RamSize = dictionarySize * 11.5 + 6MB + FilterBlockSize
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|       filterMode     FilterBlockSize
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|      SZ_FILTER_NO         0
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|      SZ_FILTER_YES      inSize
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|      SZ_FILTER_AUTO     inSize
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| 
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| 
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| Return code:
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|   SZ_OK               - OK
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|   SZ_ERROR_MEM        - Memory allocation error
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|   SZ_ERROR_PARAM      - Incorrect paramater
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|   SZ_ERROR_OUTPUT_EOF - output buffer overflow
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|   SZ_ERROR_THREAD     - errors in multithreading functions (only for Mt version)
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| */
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| 
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| enum ESzFilterMode
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| {
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|   SZ_FILTER_NO,
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|   SZ_FILTER_YES,
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|   SZ_FILTER_AUTO
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| };
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| 
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| SRes Lzma86_Encode(Byte *dest, size_t *destLen, const Byte *src, size_t srcLen,
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|     int level, UInt32 dictSize, int filterMode);
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| 
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| 
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| /*
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| Lzma86_GetUnpackSize:
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|   In:
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|     src      - input data
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|     srcLen   - input data size
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|   Out:
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|     unpackSize - size of uncompressed stream
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|   Return code:
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|     SZ_OK               - OK
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|     SZ_ERROR_INPUT_EOF  - Error in headers
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| */
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| 
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| SRes Lzma86_GetUnpackSize(const Byte *src, SizeT srcLen, UInt64 *unpackSize);
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| 
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| /*
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| Lzma86_Decode:
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|   In:
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|     dest     - output data
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|     destLen  - output data size
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|     src      - input data
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|     srcLen   - input data size
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|   Out:
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|     destLen  - processed output size
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|     srcLen   - processed input size
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|   Return code:
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|     SZ_OK           - OK
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|     SZ_ERROR_DATA  - Data error
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|     SZ_ERROR_MEM   - Memory allocation error
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|     SZ_ERROR_UNSUPPORTED - unsupported file
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|     SZ_ERROR_INPUT_EOF - it needs more bytes in input buffer
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| */
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| 
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| SRes Lzma86_Decode(Byte *dest, SizeT *destLen, const Byte *src, SizeT *srcLen);
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| 
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| EXTERN_C_END
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| 
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| #endif
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