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        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'.
    The function will decompress a minimum of 'targetOutputSize' bytes, and stop after that.
    However, it's not accurate, and may write more than 'targetOutputSize' (but <= dstCapacity).
   @return : the number of bytes decoded in the destination buffer (necessarily <= dstCapacity)
       Note : this number can be < 'targetOutputSize' should the compressed block contain less data.
             Always control how many bytes were decoded.
             If the source stream is detected malformed, the function will stop decoding and return a negative result.
             This function never writes outside of output buffer, and never reads outside of input buffer. It is therefore protected against malicious data packets.
*/
LZ4LIB_API int LZ4_decompress_safe_partial (const char* src, char* dst, int srcSize, int targetOutputSize, int dstCapacity);


/*-*********************************************
*  Streaming Compression Functions
***********************************************/
typedef union LZ4_stream_u LZ4_stream_t;   /* incomplete type (defined later) */

/*! LZ4_createStream() and LZ4_freeStream() :
 *  LZ4_createStream() will allocate and initialize an `LZ4_stream_t` structure.
 *  LZ4_freeStream() releases its memory.
 */
LZ4LIB_API LZ4_stream_t* LZ4_createStream(void);
LZ4LIB_API int           LZ4_freeStream (LZ4_stream_t* streamPtr);

/*! LZ4_resetStream() :
 *  An LZ4_stream_t structure can be allocated once and re-used multiple times.
 *  Use this function to start compressing a new stream.
 */
LZ4LIB_API void LZ4_resetStream (LZ4_stream_t* streamPtr);

/*! LZ4_loadDict() :
 *  Use this function to load a static dictionary into LZ4_stream_t.
 *  Any previous data will be forgotten, only 'dictionary' will remain in memory.
 *  Loading a size of 0 is allowed, and is the same as reset.
 * @return : dictionary size, in bytes (necessarily <= 64 KB)
 */
LZ4LIB_API int LZ4_loadDict (LZ4_stream_t* streamPtr, const char* dictionary, int dictSize);

/*! LZ4_compress_fast_continue() :
 *  Compress content into 'src' using data from previously compressed blocks, improving compression ratio.
 *  'dst' buffer must be already allocated.
 *  If dstCapacity >= LZ4_compressBound(srcSize), compression is guaranteed to succeed, and runs faster.
 *
 *  Important : Up to 64KB of previously compressed data is assumed to remain present and unmodified in memory !
 *  Special 1 : If input buffer is a double-buffer, it can have any size, including < 64 KB.
 *  Special 2 : If input buffer is a ring-buffer, it can have any size, including < 64 KB.
 *
 * @return : size of compressed block
 *           or 0 if there is an error (typically, compressed data cannot fit into 'dst')
 *  After an error, the stream status is invalid, it can only be reset or freed.
 */
LZ4LIB_API int LZ4_compress_fast_continue (LZ4_stream_t* streamPtr, const char* src, char* dst, int srcSize, int dstCapacity, int acceleration);

/*! LZ4_saveDict() :
 *  If previously compressed data block is not guaranteed to remain available at its current memory location,
 *  save it into a safer place (char* safeBuffer).
 *  Note : it's not necessary to call LZ4_loadDict() after LZ4_saveDict(), dictionary is immediately usable.
 *  @return : saved dictionary size in bytes (necessarily <= dictSize), or 0 if error.
 */
LZ4LIB_API int LZ4_saveDict (LZ4_stream_t* streamPtr, char* safeBuffer, int dictSize);


/*-**********************************************
*  Streaming Decompression Functions
*  Bufferless synchronous API
************************************************/
typedef union LZ4_streamDecode_u LZ4_streamDecode_t;   /* incomplete type (defined later) */

/*! LZ4_createStreamDecode() and LZ4_freeStreamDecode() :
 *  creation / destruction of streaming decompression tracking structure.
 *  A tracking structure can be re-used multiple times sequentially. */
LZ4LIB_API LZ4_streamDecode_t* LZ4_createStreamDecode(void);
LZ4LIB_API int                 LZ4_freeStreamDecode (LZ4_streamDecode_t* LZ4_stream);

/*! LZ4_setStreamDecode() :
 *  An LZ4_streamDecode_t structure can be allocated once and re-used multiple times.
 *  Use this function to start decompression of a new stream of blocks.
 *  A dictionary can optionnally be set. Use NULL or size 0 for a simple reset order.
 * @return : 1 if OK, 0 if error
 */
LZ4LIB_API int LZ4_setStreamDecode (LZ4_streamDecode_t* LZ4_streamDecode, const char* dictionary, int dictSize);

/*! LZ4_decompress_*_continue() :
 *  These decoding functions allow decompression of consecutive blocks in "streaming" mode.
 *  A block is an unsplittable entity, it must be presented entirely to a decompression function.
 *  Decompression functions only accept one block at a time.
 *  Previously decoded blocks *must* remain available at the memory position where they were decoded (up to 64 KB).
 *
 *  Special : if application sets a ring buffer for decompression, it must respect one of the following conditions :
 *  - Exactly same size as encoding buffer, with same update rule (block boundaries at same positions)
 *    In which case, the decoding & encoding ring buffer can have any size, including very small ones ( < 64 KB).
 *  - Larger than encoding buffer, by a minimum of maxBlockSize more bytes.
 *    maxBlockSize is implementation dependent. It's the maximum size of any single block.
 *    In which case, encoding and decoding buffers do not need to be synchronized,
 *    and encoding ring buffer can have any size, including small ones ( < 64 KB).
 *  - _At least_ 64 KB + 8 bytes + maxBlockSize.
 *    In which case, encoding and decoding buffers do not need to be synchronized,
 *    and encoding ring buffer can have any size, including larger than decoding buffer.
 *  Whenever these conditions are not possible, save the last 64KB of decoded data into a safe buffer,
 *  and indicate where it is saved using LZ4_setStreamDecode() before decompressing next block.
*/
LZ4LIB_API int LZ4_decompress_safe_continue (LZ4_streamDecode_t* LZ4_streamDecode, const char* src, char* dst, int srcSize, int dstCapacity);
LZ4LIB_API int LZ4_decompress_fast_continue (LZ4_streamDecode_t* LZ4_streamDecode, const char* src, char* dst, int originalSize);


/*! LZ4_decompress_*_usingDict() :
 *  These decoding functions work the same as
 *  a combination of LZ4_setStreamDecode() followed by LZ4_decompress_*_continue()
 *  They are stand-alone, and don't need an LZ4_streamDecode_t structure.
 */
LZ4LIB_API int LZ4_decompress_safe_usingDict (const char* src, char* dst, int srcSize, int dstCapcity, const char* dictStart, int dictSize);
LZ4LIB_API int LZ4_decompress_fast_usingDict (const char* src, char* dst, int originalSize, const char* dictStart, int dictSize);


/*^**********************************************
 * !!!!!!   STATIC LINKING ONLY   !!!!!!
 ***********************************************/
/*-************************************
 *  Private definitions
 **************************************
 * Do not use these definitions.
 * They are exposed to allow static allocation of `LZ4_stream_t` and `LZ4_streamDecode_t`.
 * Using these definitions will expose code to API and/or ABI break in future versions of the library.
 **************************************/
#define LZ4_HASHLOG   (LZ4_MEMORY_USAGE-2)
#define LZ4_HASHTABLESIZE (1 << LZ4_MEMORY_USAGE)
#define LZ4_HASH_SIZE_U32 (1 << LZ4_HASHLOG)       /* required as macro for static allocation */

#if defined(__cplusplus) || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */)
#include <stdint.h>

typedef struct {
    uint32_t hashTable[LZ4_HASH_SIZE_U32];
    uint32_t currentOffset;
    uint32_t initCheck;
    const uint8_t* dictionary;
    uint8_t* bufferStart;   /* obsolete, used for slideInputBuffer */
    uint32_t dictSize;
} LZ4_stream_t_internal;

typedef struct {
    const uint8_t* externalDict;
    size_t extDictSize;
    const uint8_t* prefixEnd;
    size_t prefixSize;
} LZ4_streamDecode_t_internal;

#else

typedef struct {
    unsigned int hashTable[LZ4_HASH_SIZE_U32];
    unsigned int currentOffset;
    unsigned int initCheck;
    const unsigned char* dictionary;
    unsigned char* bufferStart;   /* obsolete, used for slideInputBuffer */
    unsigned int dictSize;
} LZ4_stream_t_internal;

typedef struct {