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#define LZ4_VERSION_STRING LZ4_EXPAND_AND_QUOTE(LZ4_LIB_VERSION)

LZ4LIB_API int LZ4_versionNumber (void);  /**< library version number; to be used when checking dll version */
LZ4LIB_API const char* LZ4_versionString (void);   /**< library version string; to be used when checking dll version */


/*-************************************
*  Tuning parameter
**************************************/
/*!
 * LZ4_MEMORY_USAGE :
 * Memory usage formula : N->2^N Bytes (examples : 10 -> 1KB; 12 -> 4KB ; 16 -> 64KB; 20 -> 1MB; etc.)
 * Increasing memory usage improves compression ratio
 * Reduced memory usage can improve speed, due to cache effect
 * Default value is 14, for 16KB, which nicely fits into Intel x86 L1 cache
 */
#ifndef LZ4_MEMORY_USAGE
# define LZ4_MEMORY_USAGE 14
#endif

/*-************************************
*  Simple Functions
**************************************/
/*! LZ4_compress_default() :
    Compresses 'srcSize' bytes from buffer 'src'
    into already allocated 'dst' buffer of size 'dstCapacity'.
    Compression is guaranteed to succeed if 'dstCapacity' >= LZ4_compressBound(srcSize).
    It also runs faster, so it's a recommended setting.
    If the function cannot compress 'src' into a limited 'dst' budget,
    compression stops *immediately*, and the function result is zero.
    As a consequence, 'dst' content is not valid.
    This function never writes outside 'dst' buffer, nor read outside 'source' buffer.
        srcSize : supported max value is LZ4_MAX_INPUT_VALUE
        dstCapacity : full or partial size of buffer 'dst' (which must be already allocated)
        return  : the number of bytes written into buffer 'dst' (necessarily <= dstCapacity)
                  or 0 if compression fails */
LZ4LIB_API int LZ4_compress_default(const char* src, char* dst, int srcSize, int dstCapacity);

/*! LZ4_decompress_safe() :
    compressedSize : is the exact complete size of the compressed block.
    dstCapacity : is the size of destination buffer, which must be already allocated.
    return : the number of bytes decompressed into destination buffer (necessarily <= dstCapacity)
             If destination buffer is not large enough, decoding will stop and output an error code (negative value).
             If the source stream is detected malformed, the function will stop decoding and return a negative result.
             This function is protected against buffer overflow exploits, including malicious data packets.
             It never writes outside output buffer, nor reads outside input buffer.
*/
LZ4LIB_API int LZ4_decompress_safe (const char* src, char* dst, int compressedSize, int dstCapacity);


/*-************************************
*  Advanced Functions
**************************************/
#define LZ4_MAX_INPUT_SIZE        0x7E000000   /* 2 113 929 216 bytes */
#define LZ4_COMPRESSBOUND(isize)  ((unsigned)(isize) > (unsigned)LZ4_MAX_INPUT_SIZE ? 0 : (isize) + ((isize)/255) + 16)

/*!
LZ4_compressBound() :
    Provides the maximum size that LZ4 compression may output in a "worst case" scenario (input data not compressible)
    This function is primarily useful for memory allocation purposes (destination buffer size).
    Macro LZ4_COMPRESSBOUND() is also provided for compilation-time evaluation (stack memory allocation for example).
    Note that LZ4_compress_default() compress faster when dest buffer size is >= LZ4_compressBound(srcSize)
        inputSize  : max supported value is LZ4_MAX_INPUT_SIZE
        return : maximum output size in a "worst case" scenario
              or 0, if input size is too large ( > LZ4_MAX_INPUT_SIZE)
*/
LZ4LIB_API int LZ4_compressBound(int inputSize);

/*!
LZ4_compress_fast() :
    Same as LZ4_compress_default(), but allows to select an "acceleration" factor.
    The larger the acceleration value, the faster the algorithm, but also the lesser the compression.
    It's a trade-off. It can be fine tuned, with each successive value providing roughly +~3% to speed.
    An acceleration value of "1" is the same as regular LZ4_compress_default()
    Values <= 0 will be replaced by ACCELERATION_DEFAULT (see lz4.c), which is 1.
*/
LZ4LIB_API int LZ4_compress_fast (const char* src, char* dst, int srcSize, int dstCapacity, int acceleration);


/*!
LZ4_compress_fast_extState() :
    Same compression function, just using an externally allocated memory space to store compression state.
    Use LZ4_sizeofState() to know how much memory must be allocated,
    and allocate it on 8-bytes boundaries (using malloc() typically).
    Then, provide it as 'void* state' to compression function.
*/
LZ4LIB_API int LZ4_sizeofState(void);
LZ4LIB_API int LZ4_compress_fast_extState (void* state, const char* src, char* dst, int srcSize, int dstCapacity, int acceleration);


/*!
LZ4_compress_destSize() :
    Reverse the logic : compresses as much data as possible from 'src' buffer
    into already allocated buffer 'dst' of size 'targetDestSize'.
    This function either compresses the entire 'src' content into 'dst' if it's large enough,
    or fill 'dst' buffer completely with as much data as possible from 'src'.
        *srcSizePtr : will be modified to indicate how many bytes where read from 'src' to fill 'dst'.
                      New value is necessarily <= old value.
        return : Nb bytes written into 'dst' (necessarily <= targetDestSize)
                 or 0 if compression fails
*/
LZ4LIB_API int LZ4_compress_destSize (const char* src, char* dst, int* srcSizePtr, int targetDstSize);


/*!
LZ4_decompress_fast() : (unsafe!!)
    originalSize : is the original uncompressed size
    return : the number of bytes read from the source buffer (in other words, the compressed size)
             If the source stream is detected malformed, the function will stop decoding and return a negative result.
             Destination buffer must be already allocated. Its size must be >= 'originalSize' bytes.
    note : This function respects memory boundaries for *properly formed* compressed data.
           It is a bit faster than LZ4_decompress_safe().
           However, it does not provide any protection against intentionally modified data stream (malicious input).
           Use this function in trusted environment only (data to decode comes from a trusted source).
*/
LZ4LIB_API int LZ4_decompress_fast (const char* src, char* dst, int originalSize);

/*!
LZ4_decompress_safe_partial() :
    This function decompress a compressed block of size 'srcSize' at position 'src'
    into destination buffer 'dst' of size 'dstCapacity'.