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Member "lessfs-1.5.13/lib_qlz.h" of archive lessfs-1.5.13.tar.gz:

#ifndef QLZ_HEADER
#define QLZ_HEADER

// Fast data compression library
// Copyright (C) 2006-2009 Lasse Mikkel Reinhold
// lar@quicklz.com
//
// QuickLZ can be used for free under the GPL-1 or GPL-2 license (where anything 
// released into public must be open source) or under a commercial license if such 
// has been acquired (see http://www.quicklz.com/order.html). The commercial license 
// does not cover derived or ported versions created by third parties under GPL.

// You can edit following user settings. Data must be decompressed with the same 
// setting of QLZ_COMPRESSION_LEVEL and QLZ_STREAMING_BUFFER as it was compressed
// (see manual). If QLZ_STREAMING_BUFFER > 0, scratch buffers must be initially
// zeroed out (see manual). First #ifndef makes it possible to define settings from 
// the outside like the compiler command line or from higher level code.

// Version 1.4.1 final - april 2010

compr *clz_compress(unsigned char *, int);
compr *clz_decompress(unsigned char *, int);

#ifndef QLZ_COMPRESSION_LEVEL
#define QLZ_COMPRESSION_LEVEL 1
        //#define QLZ_COMPRESSION_LEVEL 2
        //#define QLZ_COMPRESSION_LEVEL 3

#define QLZ_STREAMING_BUFFER 0
        //#define QLZ_STREAMING_BUFFER 100000
        //#define QLZ_STREAMING_BUFFER 1000000

        //#define QLZ_MEMORY_SAFE
#endif

#define QLZ_VERSION_MAJOR 1
#define QLZ_VERSION_MINOR 4
#define QLZ_VERSION_REVISION 1

// Using size_t, memset() and memcpy()
#include <string.h>

// Public functions of QuickLZ
size_t qlz_size_decompressed(const char *source);
size_t qlz_size_compressed(const char *source);
size_t qlz_decompress(const char *source, void *destination,
                      char *scratch_decompress);
size_t qlz_compress(const void *source, char *destination, size_t size,
                    char *scratch_compress);
int qlz_get_setting(int setting);

// Verify compression level
#if QLZ_COMPRESSION_LEVEL != 1 && QLZ_COMPRESSION_LEVEL != 2 && QLZ_COMPRESSION_LEVEL != 3
#error QLZ_COMPRESSION_LEVEL must be 1, 2 or 3
#endif

// Compute QLZ_SCRATCH_COMPRESS and QLZ_SCRATCH_DECOMPRESS
#if QLZ_COMPRESSION_LEVEL == 1
#define QLZ_POINTERS 1
#define QLZ_HASH_VALUES 4096
#elif QLZ_COMPRESSION_LEVEL == 2
#define QLZ_POINTERS 4
#define QLZ_HASH_VALUES 2048
#elif QLZ_COMPRESSION_LEVEL == 3
#define QLZ_POINTERS 16
#define QLZ_HASH_VALUES 4096
#endif

typedef struct {
#if QLZ_COMPRESSION_LEVEL == 1
    unsigned int cache[QLZ_POINTERS];
#endif
    const unsigned char *offset[QLZ_POINTERS];
} qlz_hash_compress;

typedef struct {
    const unsigned char *offset[QLZ_POINTERS];
} qlz_hash_decompress;


#define QLZ_ALIGNMENT_PADD 8
#define QLZ_BUFFER_COUNTER 8

#define QLZ_SCRATCH_COMPRESS (QLZ_ALIGNMENT_PADD + QLZ_BUFFER_COUNTER + QLZ_STREAMING_BUFFER + sizeof(qlz_hash_compress[QLZ_HASH_VALUES]) + QLZ_HASH_VALUES)

#if QLZ_COMPRESSION_LEVEL < 3
#define QLZ_SCRATCH_DECOMPRESS (QLZ_ALIGNMENT_PADD + QLZ_BUFFER_COUNTER + QLZ_STREAMING_BUFFER + sizeof(qlz_hash_decompress[QLZ_HASH_VALUES]) + QLZ_HASH_VALUES)
#else
#define QLZ_SCRATCH_DECOMPRESS (QLZ_ALIGNMENT_PADD + QLZ_BUFFER_COUNTER + QLZ_STREAMING_BUFFER)
#endif

#endif