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+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 + 7zTypes.h + Precomp.h + Compiler.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 + 7zTypes.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 + 7zTypes.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: 
+  7zTypes.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