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    }
    memcpy(cdict->dictContent, dictStart, dictSize);
    LZ4_resetStream(cdict->fastCtx);
    LZ4_loadDict (cdict->fastCtx, (const char*)cdict->dictContent, (int)dictSize);
    LZ4_resetStreamHC(cdict->HCCtx, LZ4HC_CLEVEL_DEFAULT);
    LZ4_loadDictHC(cdict->HCCtx, (const char*)cdict->dictContent, (int)dictSize);
    return cdict;
}

void LZ4F_freeCDict(LZ4F_CDict* cdict)
{
    if (cdict==NULL) return;  /* support free on NULL */
    FREEMEM(cdict->dictContent);
    LZ4_freeStream(cdict->fastCtx);
    LZ4_freeStreamHC(cdict->HCCtx);
    FREEMEM(cdict);
}


/*-*********************************
*  Advanced compression functions
***********************************/

/*! LZ4F_createCompressionContext() :
 *  The first thing to do is to create a compressionContext object, which will be used in all compression operations.
 *  This is achieved using LZ4F_createCompressionContext(), which takes as argument a version and an LZ4F_preferences_t structure.
 *  The version provided MUST be LZ4F_VERSION. It is intended to track potential incompatible differences between different binaries.
 *  The function will provide a pointer to an allocated LZ4F_compressionContext_t object.
 *  If the result LZ4F_errorCode_t is not OK_NoError, there was an error during context creation.
 *  Object can release its memory using LZ4F_freeCompressionContext();
 */
LZ4F_errorCode_t LZ4F_createCompressionContext(LZ4F_compressionContext_t* LZ4F_compressionContextPtr, unsigned version)
{
    LZ4F_cctx_t* const cctxPtr = (LZ4F_cctx_t*)ALLOCATOR(sizeof(LZ4F_cctx_t));
    if (cctxPtr==NULL) return err0r(LZ4F_ERROR_allocation_failed);

    cctxPtr->version = version;
    cctxPtr->cStage = 0;   /* Next stage : init stream */

    *LZ4F_compressionContextPtr = (LZ4F_compressionContext_t)cctxPtr;

    return LZ4F_OK_NoError;
}


LZ4F_errorCode_t LZ4F_freeCompressionContext(LZ4F_compressionContext_t LZ4F_compressionContext)
{
    LZ4F_cctx_t* const cctxPtr = (LZ4F_cctx_t*)LZ4F_compressionContext;

    if (cctxPtr != NULL) {  /* support free on NULL */
       FREEMEM(cctxPtr->lz4CtxPtr);  /* works because LZ4_streamHC_t and LZ4_stream_t are simple POD types */
       FREEMEM(cctxPtr->tmpBuff);
       FREEMEM(LZ4F_compressionContext);
    }

    return LZ4F_OK_NoError;
}


/*! LZ4F_compressBegin_usingCDict() :
 *  init streaming compression and writes frame header into dstBuffer.
 *  dstBuffer must be >= LZ4F_HEADER_SIZE_MAX bytes.
 * @return : number of bytes written into dstBuffer for the header
 *           or an error code (can be tested using LZ4F_isError())
 */
size_t LZ4F_compressBegin_usingCDict(LZ4F_cctx* cctxPtr,
                          void* dstBuffer, size_t dstCapacity,
                          const LZ4F_CDict* cdict,
                          const LZ4F_preferences_t* preferencesPtr)
{
    LZ4F_preferences_t prefNull;
    BYTE* const dstStart = (BYTE*)dstBuffer;
    BYTE* dstPtr = dstStart;
    BYTE* headerStart;

    if (dstCapacity < maxFHSize) return err0r(LZ4F_ERROR_dstMaxSize_tooSmall);
    memset(&prefNull, 0, sizeof(prefNull));
    if (preferencesPtr == NULL) preferencesPtr = &prefNull;
    cctxPtr->prefs = *preferencesPtr;

    /* Ctx Management */
    {   U32 const ctxTypeID = (cctxPtr->prefs.compressionLevel < LZ4HC_CLEVEL_MIN) ? 1 : 2;  /* 0:nothing ; 1:LZ4 table ; 2:HC tables */
        if (cctxPtr->lz4CtxLevel < ctxTypeID) {
            FREEMEM(cctxPtr->lz4CtxPtr);
            if (cctxPtr->prefs.compressionLevel < LZ4HC_CLEVEL_MIN)
                cctxPtr->lz4CtxPtr = (void*)LZ4_createStream();
            else
                cctxPtr->lz4CtxPtr = (void*)LZ4_createStreamHC();
            if (cctxPtr->lz4CtxPtr == NULL) return err0r(LZ4F_ERROR_allocation_failed);
            cctxPtr->lz4CtxLevel = ctxTypeID;
    }   }

    /* Buffer Management */
    if (cctxPtr->prefs.frameInfo.blockSizeID == 0)
        cctxPtr->prefs.frameInfo.blockSizeID = LZ4F_BLOCKSIZEID_DEFAULT;
    cctxPtr->maxBlockSize = LZ4F_getBlockSize(cctxPtr->prefs.frameInfo.blockSizeID);

    {   size_t const requiredBuffSize = preferencesPtr->autoFlush ?
                (cctxPtr->prefs.frameInfo.blockMode == LZ4F_blockLinked) * 64 KB :  /* only needs windows size */
                cctxPtr->maxBlockSize + ((cctxPtr->prefs.frameInfo.blockMode == LZ4F_blockLinked) * 128 KB);

        if (cctxPtr->maxBufferSize < requiredBuffSize) {
            cctxPtr->maxBufferSize = 0;
            FREEMEM(cctxPtr->tmpBuff);
            cctxPtr->tmpBuff = (BYTE*)ALLOCATOR(requiredBuffSize);
            if (cctxPtr->tmpBuff == NULL) return err0r(LZ4F_ERROR_allocation_failed);
            cctxPtr->maxBufferSize = requiredBuffSize;
    }   }
    cctxPtr->tmpIn = cctxPtr->tmpBuff;
    cctxPtr->tmpInSize = 0;
    XXH32_reset(&(cctxPtr->xxh), 0);

    /* context init */
    cctxPtr->cdict = cdict;
    if (cctxPtr->prefs.frameInfo.blockMode == LZ4F_blockLinked) {
        /* frame init only for blockLinked : blockIndependent will be init at each block */
        if (cdict) {
            if (cctxPtr->prefs.compressionLevel < LZ4HC_CLEVEL_MIN) {
                memcpy(cctxPtr->lz4CtxPtr, cdict->fastCtx, sizeof(*cdict->fastCtx));
            } else {
                memcpy(cctxPtr->lz4CtxPtr, cdict->HCCtx, sizeof(*cdict->HCCtx));
                LZ4_setCompressionLevel((LZ4_streamHC_t*)cctxPtr->lz4CtxPtr, cctxPtr->prefs.compressionLevel);
            }
        } else {
            if (cctxPtr->prefs.compressionLevel < LZ4HC_CLEVEL_MIN)
                LZ4_resetStream((LZ4_stream_t*)(cctxPtr->lz4CtxPtr));
            else
                LZ4_resetStreamHC((LZ4_streamHC_t*)(cctxPtr->lz4CtxPtr), cctxPtr->prefs.compressionLevel);
        }
    }

    /* Magic Number */
    LZ4F_writeLE32(dstPtr, LZ4F_MAGICNUMBER);
    dstPtr += 4;
    headerStart = dstPtr;

    /* FLG Byte */
    *dstPtr++ = (BYTE)(((1 & _2BITS) << 6)    /* Version('01') */
        + ((cctxPtr->prefs.frameInfo.blockMode & _1BIT ) << 5)
        + ((cctxPtr->prefs.frameInfo.blockChecksumFlag & _1BIT ) << 4)
        + ((cctxPtr->prefs.frameInfo.contentSize > 0) << 3)
        + ((cctxPtr->prefs.frameInfo.contentChecksumFlag & _1BIT ) << 2)
        +  (cctxPtr->prefs.frameInfo.dictID > 0) );
    /* BD Byte */
    *dstPtr++ = (BYTE)((cctxPtr->prefs.frameInfo.blockSizeID & _3BITS) << 4);
    /* Optional Frame content size field */
    if (cctxPtr->prefs.frameInfo.contentSize) {
        LZ4F_writeLE64(dstPtr, cctxPtr->prefs.frameInfo.contentSize);
        dstPtr += 8;
        cctxPtr->totalInSize = 0;
    }
    /* Optional dictionary ID field */
    if (cctxPtr->prefs.frameInfo.dictID) {
        LZ4F_writeLE32(dstPtr, cctxPtr->prefs.frameInfo.dictID);
        dstPtr += 4;
    }
    /* Header CRC Byte */
    *dstPtr = LZ4F_headerChecksum(headerStart, dstPtr - headerStart);
    dstPtr++;

    cctxPtr->cStage = 1;   /* header written, now request input data block */
    return (dstPtr - dstStart);
}


/*! LZ4F_compressBegin() :
 *  init streaming compression and writes frame header into dstBuffer.
 *  dstBuffer must be >= LZ4F_HEADER_SIZE_MAX bytes.
 *  preferencesPtr can be NULL, in which case default parameters are selected.
 * @return : number of bytes written into dstBuffer for the header
 *           or an error code (can be tested using LZ4F_isError())
 */
size_t LZ4F_compressBegin(LZ4F_cctx* cctxPtr,
                          void* dstBuffer, size_t dstCapacity,
                          const LZ4F_preferences_t* preferencesPtr)
{
    return LZ4F_compressBegin_usingCDict(cctxPtr, dstBuffer, dstCapacity,
                                         NULL, preferencesPtr);
}


/*  LZ4F_compressBound() :
 * @return minimum capacity of dstBuffer for a given srcSize to handle worst case scenario.
 *  LZ4F_preferences_t structure is optional : if NULL, preferences will be set to cover worst case scenario.
 *  This function cannot fail.
 */
size_t LZ4F_compressBound(size_t srcSize, const LZ4F_preferences_t* preferencesPtr)
{
    return LZ4F_compressBound_internal(srcSize, preferencesPtr, (size_t)-1);
}


typedef int (*compressFunc_t)(void* ctx, const char* src, char* dst, int srcSize, int dstSize, int level, const LZ4F_CDict* cdict);


/*! LZ4F_makeBlock():
 *  compress a single block, add header and checksum
 *  assumption : dst buffer capacity is >= srcSize */
static size_t LZ4F_makeBlock(void* dst, const void* src, size_t srcSize,
                             compressFunc_t compress, void* lz4ctx, int level,
                             const LZ4F_CDict* cdict, LZ4F_blockChecksum_t crcFlag)
{
    BYTE* const cSizePtr = (BYTE*)dst;
    U32 cSize = (U32)compress(lz4ctx, (const char*)src, (char*)(cSizePtr+4),
                                      (int)(srcSize), (int)(srcSize-1),
                                      level, cdict);
    LZ4F_writeLE32(cSizePtr, cSize);
    if (cSize == 0) {  /* compression failed */
        cSize = (U32)srcSize;
        LZ4F_writeLE32(cSizePtr, cSize | LZ4F_BLOCKUNCOMPRESSED_FLAG);
        memcpy(cSizePtr+4, src, srcSize);
    }
    if (crcFlag) {
        U32 const crc32 = XXH32(cSizePtr+4, cSize, 0);  /* checksum of compressed data */
        LZ4F_writeLE32(cSizePtr+4+cSize, crc32);
    }
    return 4 + cSize + ((U32)crcFlag)*4;
}


static int LZ4F_compressBlock(void* ctx, const char* src, char* dst, int srcSize, int dstCapacity, int level, const LZ4F_CDict* cdict)
{
    int const acceleration = (level < -1) ? -level : 1;
    if (cdict) {
        memcpy(ctx, cdict->fastCtx, sizeof(*cdict->fastCtx));
        return LZ4_compress_fast_continue((LZ4_stream_t*)ctx, src, dst, srcSize, dstCapacity, acceleration);
    }