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/*
* expand_context.h - decompressor context definitions
*
* Copyright (C) 2019 Emmanuel Marty
*
* This software is provided 'as-is', without any express or implied
* warranty. In no event will the authors be held liable for any damages
* arising from the use of this software.
*
* Permission is granted to anyone to use this software for any purpose,
* including commercial applications, and to alter it and redistribute it
* freely, subject to the following restrictions:
*
* 1. The origin of this software must not be misrepresented; you must not
* claim that you wrote the original software. If you use this software
* in a product, an acknowledgment in the product documentation would be
* appreciated but is not required.
* 2. Altered source versions must be plainly marked as such, and must not be
* misrepresented as being the original software.
* 3. This notice may not be removed or altered from any source distribution.
*/
/*
* Uses the libdivsufsort library Copyright (c) 2003-2008 Yuta Mori
*
* Inspired by LZ4 by Yann Collet. https://github.com/lz4/lz4
* With help, ideas, optimizations and speed measurements by spke <zxintrospec@gmail.com>
* With ideas from Lizard by Przemyslaw Skibinski and Yann Collet. https://github.com/inikep/lizard
* Also with ideas from smallz4 by Stephan Brumme. https://create.stephan-brumme.com/smallz4/
*
*/
#include <stdlib.h>
#include <string.h>
#include "expand_context.h"
#include "expand_block_v1.h"
#include "expand_block_v2.h"
#include "lib.h"
/**
* Decompress one data block
*
* @param pInBlock pointer to compressed data
* @param nBlockSize size of compressed data, in bytes
* @param pOutData pointer to output decompression buffer (previously decompressed bytes + room for decompressing this block)
* @param nOutDataOffset starting index of where to store decompressed bytes in output buffer (and size of previously decompressed bytes)
* @param nBlockMaxSize total size of output decompression buffer, in bytes
* @param nFormatVersion version of format to use (1-2)
* @param nFlags compression flags (LZSA_FLAG_xxx)
*
* @return size of decompressed data in bytes, or -1 for error
*/
int lzsa_decompressor_expand_block(unsigned char *pInBlock, int nBlockSize, unsigned char *pOutData, int nOutDataOffset, int nBlockMaxSize, const int nFormatVersion, const int nFlags) {
int nDecompressedSize;
if (nFlags & LZSA_FLAG_RAW_BACKWARD) {
lzsa_reverse_buffer(pInBlock, nBlockSize);
}
if (nFormatVersion == 1)
nDecompressedSize = lzsa_decompressor_expand_block_v1(pInBlock, nBlockSize, pOutData, nOutDataOffset, nBlockMaxSize);
else if (nFormatVersion == 2)
nDecompressedSize = lzsa_decompressor_expand_block_v2(pInBlock, nBlockSize, pOutData, nOutDataOffset, nBlockMaxSize);
else
nDecompressedSize = -1;
if (nDecompressedSize != -1 && (nFlags & LZSA_FLAG_RAW_BACKWARD)) {
lzsa_reverse_buffer(pOutData + nOutDataOffset, nDecompressedSize);
}
if (nFlags & LZSA_FLAG_RAW_BACKWARD) {
lzsa_reverse_buffer(pInBlock, nBlockSize);
}
return nDecompressedSize;
}
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