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diff --git a/deps/lzma-16.04/DOC/lzma.txt b/deps/lzma-16.04/DOC/lzma.txt new file mode 100644 index 0000000..f9a80ae --- /dev/null +++ b/deps/lzma-16.04/DOC/lzma.txt @@ -0,0 +1,328 @@ +LZMA compression
+----------------
+Version: 9.35
+
+This file describes LZMA encoding and decoding functions written in C language.
+
+LZMA is an improved version of famous LZ77 compression algorithm.
+It was improved in way of maximum increasing of compression ratio,
+keeping high decompression speed and low memory requirements for
+decompressing.
+
+Note: you can read also LZMA Specification (lzma-specification.txt from LZMA SDK)
+
+Also you can look source code for LZMA encoding and decoding:
+ C/Util/Lzma/LzmaUtil.c
+
+
+LZMA compressed file format
+---------------------------
+Offset Size Description
+ 0 1 Special LZMA properties (lc,lp, pb in encoded form)
+ 1 4 Dictionary size (little endian)
+ 5 8 Uncompressed size (little endian). -1 means unknown size
+ 13 Compressed data
+
+
+
+ANSI-C LZMA Decoder
+~~~~~~~~~~~~~~~~~~~
+
+Please note that interfaces for ANSI-C code were changed in LZMA SDK 4.58.
+If you want to use old interfaces you can download previous version of LZMA SDK
+from sourceforge.net site.
+
+To use ANSI-C LZMA Decoder you need the following files:
+1) LzmaDec.h + LzmaDec.c + Types.h
+
+Look example code:
+ C/Util/Lzma/LzmaUtil.c
+
+
+Memory requirements for LZMA decoding
+-------------------------------------
+
+Stack usage of LZMA decoding function for local variables is not
+larger than 200-400 bytes.
+
+LZMA Decoder uses dictionary buffer and internal state structure.
+Internal state structure consumes
+ state_size = (4 + (1.5 << (lc + lp))) KB
+by default (lc=3, lp=0), state_size = 16 KB.
+
+
+How To decompress data
+----------------------
+
+LZMA Decoder (ANSI-C version) now supports 2 interfaces:
+1) Single-call Decompressing
+2) Multi-call State Decompressing (zlib-like interface)
+
+You must use external allocator:
+Example:
+void *SzAlloc(void *p, size_t size) { p = p; return malloc(size); }
+void SzFree(void *p, void *address) { p = p; free(address); }
+ISzAlloc alloc = { SzAlloc, SzFree };
+
+You can use p = p; operator to disable compiler warnings.
+
+
+Single-call Decompressing
+-------------------------
+When to use: RAM->RAM decompressing
+Compile files: LzmaDec.h + LzmaDec.c + Types.h
+Compile defines: no defines
+Memory Requirements:
+ - Input buffer: compressed size
+ - Output buffer: uncompressed size
+ - LZMA Internal Structures: state_size (16 KB for default settings)
+
+Interface:
+ int LzmaDecode(Byte *dest, SizeT *destLen, const Byte *src, SizeT *srcLen,
+ const Byte *propData, unsigned propSize, ELzmaFinishMode finishMode,
+ ELzmaStatus *status, ISzAlloc *alloc);
+ In:
+ dest - output data
+ destLen - output data size
+ src - input data
+ srcLen - input data size
+ propData - LZMA properties (5 bytes)
+ propSize - size of propData buffer (5 bytes)
+ finishMode - It has meaning only if the decoding reaches output limit (*destLen).
+ LZMA_FINISH_ANY - Decode just destLen bytes.
+ LZMA_FINISH_END - Stream must be finished after (*destLen).
+ You can use LZMA_FINISH_END, when you know that
+ current output buffer covers last bytes of stream.
+ alloc - Memory allocator.
+
+ Out:
+ destLen - processed output size
+ srcLen - processed input size
+
+ Output:
+ SZ_OK
+ status:
+ LZMA_STATUS_FINISHED_WITH_MARK
+ LZMA_STATUS_NOT_FINISHED
+ LZMA_STATUS_MAYBE_FINISHED_WITHOUT_MARK
+ SZ_ERROR_DATA - Data error
+ SZ_ERROR_MEM - Memory allocation error
+ SZ_ERROR_UNSUPPORTED - Unsupported properties
+ SZ_ERROR_INPUT_EOF - It needs more bytes in input buffer (src).
+
+ If LZMA decoder sees end_marker before reaching output limit, it returns OK result,
+ and output value of destLen will be less than output buffer size limit.
+
+ You can use multiple checks to test data integrity after full decompression:
+ 1) Check Result and "status" variable.
+ 2) Check that output(destLen) = uncompressedSize, if you know real uncompressedSize.
+ 3) Check that output(srcLen) = compressedSize, if you know real compressedSize.
+ You must use correct finish mode in that case. */
+
+
+Multi-call State Decompressing (zlib-like interface)
+----------------------------------------------------
+
+When to use: file->file decompressing
+Compile files: LzmaDec.h + LzmaDec.c + Types.h
+
+Memory Requirements:
+ - Buffer for input stream: any size (for example, 16 KB)
+ - Buffer for output stream: any size (for example, 16 KB)
+ - LZMA Internal Structures: state_size (16 KB for default settings)
+ - LZMA dictionary (dictionary size is encoded in LZMA properties header)
+
+1) read LZMA properties (5 bytes) and uncompressed size (8 bytes, little-endian) to header:
+ unsigned char header[LZMA_PROPS_SIZE + 8];
+ ReadFile(inFile, header, sizeof(header)
+
+2) Allocate CLzmaDec structures (state + dictionary) using LZMA properties
+
+ CLzmaDec state;
+ LzmaDec_Constr(&state);
+ res = LzmaDec_Allocate(&state, header, LZMA_PROPS_SIZE, &g_Alloc);
+ if (res != SZ_OK)
+ return res;
+
+3) Init LzmaDec structure before any new LZMA stream. And call LzmaDec_DecodeToBuf in loop
+
+ LzmaDec_Init(&state);
+ for (;;)
+ {
+ ...
+ int res = LzmaDec_DecodeToBuf(CLzmaDec *p, Byte *dest, SizeT *destLen,
+ const Byte *src, SizeT *srcLen, ELzmaFinishMode finishMode);
+ ...
+ }
+
+
+4) Free all allocated structures
+ LzmaDec_Free(&state, &g_Alloc);
+
+Look example code:
+ C/Util/Lzma/LzmaUtil.c
+
+
+How To compress data
+--------------------
+
+Compile files:
+ Types.h
+ Threads.h
+ LzmaEnc.h
+ LzmaEnc.c
+ LzFind.h
+ LzFind.c
+ LzFindMt.h
+ LzFindMt.c
+ LzHash.h
+
+Memory Requirements:
+ - (dictSize * 11.5 + 6 MB) + state_size
+
+Lzma Encoder can use two memory allocators:
+1) alloc - for small arrays.
+2) allocBig - for big arrays.
+
+For example, you can use Large RAM Pages (2 MB) in allocBig allocator for
+better compression speed. Note that Windows has bad implementation for
+Large RAM Pages.
+It's OK to use same allocator for alloc and allocBig.
+
+
+Single-call Compression with callbacks
+--------------------------------------
+
+Look example code:
+ C/Util/Lzma/LzmaUtil.c
+
+When to use: file->file compressing
+
+1) you must implement callback structures for interfaces:
+ISeqInStream
+ISeqOutStream
+ICompressProgress
+ISzAlloc
+
+static void *SzAlloc(void *p, size_t size) { p = p; return MyAlloc(size); }
+static void SzFree(void *p, void *address) { p = p; MyFree(address); }
+static ISzAlloc g_Alloc = { SzAlloc, SzFree };
+
+ CFileSeqInStream inStream;
+ CFileSeqOutStream outStream;
+
+ inStream.funcTable.Read = MyRead;
+ inStream.file = inFile;
+ outStream.funcTable.Write = MyWrite;
+ outStream.file = outFile;
+
+
+2) Create CLzmaEncHandle object;
+
+ CLzmaEncHandle enc;
+
+ enc = LzmaEnc_Create(&g_Alloc);
+ if (enc == 0)
+ return SZ_ERROR_MEM;
+
+
+3) initialize CLzmaEncProps properties;
+
+ LzmaEncProps_Init(&props);
+
+ Then you can change some properties in that structure.
+
+4) Send LZMA properties to LZMA Encoder
+
+ res = LzmaEnc_SetProps(enc, &props);
+
+5) Write encoded properties to header
+
+ Byte header[LZMA_PROPS_SIZE + 8];
+ size_t headerSize = LZMA_PROPS_SIZE;
+ UInt64 fileSize;
+ int i;
+
+ res = LzmaEnc_WriteProperties(enc, header, &headerSize);
+ fileSize = MyGetFileLength(inFile);
+ for (i = 0; i < 8; i++)
+ header[headerSize++] = (Byte)(fileSize >> (8 * i));
+ MyWriteFileAndCheck(outFile, header, headerSize)
+
+6) Call encoding function:
+ res = LzmaEnc_Encode(enc, &outStream.funcTable, &inStream.funcTable,
+ NULL, &g_Alloc, &g_Alloc);
+
+7) Destroy LZMA Encoder Object
+ LzmaEnc_Destroy(enc, &g_Alloc, &g_Alloc);
+
+
+If callback function return some error code, LzmaEnc_Encode also returns that code
+or it can return the code like SZ_ERROR_READ, SZ_ERROR_WRITE or SZ_ERROR_PROGRESS.
+
+
+Single-call RAM->RAM Compression
+--------------------------------
+
+Single-call RAM->RAM Compression is similar to Compression with callbacks,
+but you provide pointers to buffers instead of pointers to stream callbacks:
+
+SRes LzmaEncode(Byte *dest, SizeT *destLen, const Byte *src, SizeT srcLen,
+ const CLzmaEncProps *props, Byte *propsEncoded, SizeT *propsSize, int writeEndMark,
+ ICompressProgress *progress, ISzAlloc *alloc, ISzAlloc *allocBig);
+
+Return code:
+ SZ_OK - OK
+ SZ_ERROR_MEM - Memory allocation error
+ SZ_ERROR_PARAM - Incorrect paramater
+ SZ_ERROR_OUTPUT_EOF - output buffer overflow
+ SZ_ERROR_THREAD - errors in multithreading functions (only for Mt version)
+
+
+
+Defines
+-------
+
+_LZMA_SIZE_OPT - Enable some optimizations in LZMA Decoder to get smaller executable code.
+
+_LZMA_PROB32 - It can increase the speed on some 32-bit CPUs, but memory usage for
+ some structures will be doubled in that case.
+
+_LZMA_UINT32_IS_ULONG - Define it if int is 16-bit on your compiler and long is 32-bit.
+
+_LZMA_NO_SYSTEM_SIZE_T - Define it if you don't want to use size_t type.
+
+
+_7ZIP_PPMD_SUPPPORT - Define it if you don't want to support PPMD method in AMSI-C .7z decoder.
+
+
+C++ LZMA Encoder/Decoder
+~~~~~~~~~~~~~~~~~~~~~~~~
+C++ LZMA code use COM-like interfaces. So if you want to use it,
+you can study basics of COM/OLE.
+C++ LZMA code is just wrapper over ANSI-C code.
+
+
+C++ Notes
+~~~~~~~~~~~~~~~~~~~~~~~~
+If you use some C++ code folders in 7-Zip (for example, C++ code for .7z handling),
+you must check that you correctly work with "new" operator.
+7-Zip can be compiled with MSVC 6.0 that doesn't throw "exception" from "new" operator.
+So 7-Zip uses "CPP\Common\NewHandler.cpp" that redefines "new" operator:
+operator new(size_t size)
+{
+ void *p = ::malloc(size);
+ if (p == 0)
+ throw CNewException();
+ return p;
+}
+If you use MSCV that throws exception for "new" operator, you can compile without
+"NewHandler.cpp". So standard exception will be used. Actually some code of
+7-Zip catches any exception in internal code and converts it to HRESULT code.
+So you don't need to catch CNewException, if you call COM interfaces of 7-Zip.
+
+---
+
+http://www.7-zip.org
+http://www.7-zip.org/sdk.html
+http://www.7-zip.org/support.html
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