contrib/python-zstandard/zstd/compress/zstd_compress.c

30923:5b60464efbde

/*-*************************************
*  Context memory management
***************************************/
struct ZSTD_CCtx_s
{
    const BYTE* nextSrc;    /* next block here to continue on current prefix */
    const BYTE* base;       /* All regular indexes relative to this position */
    const BYTE* dictBase;   /* extDict indexes relative to this position */
    U32   dictLimit;        /* below that point, need extDict */
    U32   lowLimit;         /* below that point, no more data */
    U32   nextToUpdate;     /* index from which to continue dictionary update */
    U32   nextToUpdate3;    /* index from which to continue dictionary update */
    U32   hashLog3;         /* dispatch table : larger == faster, more memory */
    U32   loadedDictEnd;
    ZSTD_compressionStage_e stage;
    U32   rep[ZSTD_REP_NUM];
    U32   savedRep[ZSTD_REP_NUM];
    U32   dictID;
    ZSTD_parameters params;
    void* workSpace;
    size_t workSpaceSize;
    size_t blockSize;

    if (!customMem.customAlloc || !customMem.customFree) return NULL;

    cctx = (ZSTD_CCtx*) ZSTD_malloc(sizeof(ZSTD_CCtx), customMem);
    if (!cctx) return NULL;
    memset(cctx, 0, sizeof(ZSTD_CCtx));
    memcpy(&(cctx->customMem), &customMem, sizeof(customMem));
    return cctx;
}

size_t ZSTD_freeCCtx(ZSTD_CCtx* cctx)
{

size_t ZSTD_sizeof_CCtx(const ZSTD_CCtx* cctx)
{
    if (cctx==NULL) return 0;   /* support sizeof on NULL */
    return sizeof(*cctx) + cctx->workSpaceSize;
}

const seqStore_t* ZSTD_getSeqStore(const ZSTD_CCtx* ctx)   /* hidden interface */
{
    return &(ctx->seqStore);

        return 0;
    }
}


/*! ZSTD_copyCCtx() :
*   Duplicate an existing context `srcCCtx` into another one `dstCCtx`.
*   Only works during stage ZSTDcs_init (i.e. after creation, but before first call to ZSTD_compressContinue()).
*   @return : 0, or an error code */

    { size_t const minGain = ZSTD_minGain(srcSize);
      size_t const maxCSize = srcSize - minGain;
      if ((size_t)(op-ostart) >= maxCSize) return 0; }

    /* confirm repcodes */
    { int i; for (i=0; i<ZSTD_REP_NUM; i++) zc->rep[i] = zc->savedRep[i]; }

    return op - ostart;
}


/*! ZSTD_storeSeq() :
    Store a sequence (literal length, literals, offset code and match length code) into seqStore_t.
    `offsetCode` : distance to match, or 0 == repCode.
    `matchCode` : matchLength - MINMATCH
*/
MEM_STATIC void ZSTD_storeSeq(seqStore_t* seqStorePtr, size_t litLength, const void* literals, U32 offsetCode, size_t matchCode)
{
#if 0  /* for debug */
    static const BYTE* g_start = NULL;
    const U32 pos = (U32)((const BYTE*)literals - g_start);
    if (g_start==NULL) g_start = (const BYTE*)literals;
    //if ((pos > 1) && (pos < 50000))
        printf("Cpos %6u :%5u literals & match %3u bytes at distance %6u \n",
               pos, (U32)litLength, (U32)matchCode+MINMATCH, (U32)offsetCode);
#endif
    /* copy Literals */
    ZSTD_wildcopy(seqStorePtr->lit, literals, litLength);
    seqStorePtr->lit += litLength;

                anchor = ip;
                continue;   /* faster when present ... (?) */
    }   }   }

    /* save reps for next block */
    cctx->savedRep[0] = offset_1 ? offset_1 : offsetSaved;
    cctx->savedRep[1] = offset_2 ? offset_2 : offsetSaved;

    /* Last Literals */
    {   size_t const lastLLSize = iend - anchor;
        memcpy(seqStorePtr->lit, anchor, lastLLSize);
        seqStorePtr->lit += lastLLSize;

                }
                break;
    }   }   }

    /* save reps for next block */
    ctx->savedRep[0] = offset_1; ctx->savedRep[1] = offset_2;

    /* Last Literals */
    {   size_t const lastLLSize = iend - anchor;
        memcpy(seqStorePtr->lit, anchor, lastLLSize);
        seqStorePtr->lit += lastLLSize;

                anchor = ip;
                continue;   /* faster when present ... (?) */
    }   }   }

    /* save reps for next block */
    cctx->savedRep[0] = offset_1 ? offset_1 : offsetSaved;
    cctx->savedRep[1] = offset_2 ? offset_2 : offsetSaved;

    /* Last Literals */
    {   size_t const lastLLSize = iend - anchor;
        memcpy(seqStorePtr->lit, anchor, lastLLSize);
        seqStorePtr->lit += lastLLSize;

                }
                break;
    }   }   }

    /* save reps for next block */
    ctx->savedRep[0] = offset_1; ctx->savedRep[1] = offset_2;

    /* Last Literals */
    {   size_t const lastLLSize = iend - anchor;
        memcpy(seqStorePtr->lit, anchor, lastLLSize);
        seqStorePtr->lit += lastLLSize;

            anchor = ip;
            continue;   /* faster when present ... (?) */
    }   }

    /* Save reps for next block */
    ctx->savedRep[0] = offset_1 ? offset_1 : savedOffset;
    ctx->savedRep[1] = offset_2 ? offset_2 : savedOffset;

    /* Last Literals */
    {   size_t const lastLLSize = iend - anchor;
        memcpy(seqStorePtr->lit, anchor, lastLLSize);
        seqStorePtr->lit += lastLLSize;

            }
            break;
    }   }

    /* Save reps for next block */
    ctx->savedRep[0] = offset_1; ctx->savedRep[1] = offset_2;

    /* Last Literals */
    {   size_t const lastLLSize = iend - anchor;
        memcpy(seqStorePtr->lit, anchor, lastLLSize);
        seqStorePtr->lit += lastLLSize;

        cctx->lowLimit = lowLimitMax;
    }

    cctx->nextSrc = ip + srcSize;

    {   size_t const cSize = frame ?
                             ZSTD_compress_generic (cctx, dst, dstCapacity, src, srcSize, lastFrameChunk) :
                             ZSTD_compressBlock_internal (cctx, dst, dstCapacity, src, srcSize);
        if (ZSTD_isError(cSize)) return cSize;
        return cSize + fhSize;
    }
}


size_t ZSTD_compressContinue (ZSTD_CCtx* cctx,
                              void* dst, size_t dstCapacity,

    zc->lowLimit = zc->dictLimit;
    zc->dictLimit = (U32)(zc->nextSrc - zc->base);
    zc->dictBase = zc->base;
    zc->base += ip - zc->nextSrc;
    zc->nextToUpdate = zc->dictLimit;
    zc->loadedDictEnd = (U32)(iend - zc->base);

    zc->nextSrc = iend;
    if (srcSize <= HASH_READ_SIZE) return 0;

    switch(zc->params.cParams.strategy)

        CHECK_E(FSE_buildCTable_wksp(cctx->litlengthCTable, litlengthNCount, litlengthMaxValue, litlengthLog, scratchBuffer, sizeof(scratchBuffer)), dictionary_corrupted);
        dictPtr += litlengthHeaderSize;
    }

    if (dictPtr+12 > dictEnd) return ERROR(dictionary_corrupted);
    cctx->rep[0] = MEM_readLE32(dictPtr+0); if (cctx->rep[0] >= dictSize) return ERROR(dictionary_corrupted);
    cctx->rep[1] = MEM_readLE32(dictPtr+4); if (cctx->rep[1] >= dictSize) return ERROR(dictionary_corrupted);
    cctx->rep[2] = MEM_readLE32(dictPtr+8); if (cctx->rep[2] >= dictSize) return ERROR(dictionary_corrupted);
    dictPtr += 12;

    {   U32 offcodeMax = MaxOff;
        if ((size_t)(dictEnd - dictPtr) <= ((U32)-1) - 128 KB) {
            U32 const maxOffset = (U32)(dictEnd - dictPtr) + 128 KB; /* The maximum offset that must be supported */

        if (ZSTD_isError(loadError)) return loadError;
        return ZSTD_loadDictionaryContent(zc, (const char*)dict+eSize, dictSize-eSize);
    }
}


/*! ZSTD_compressBegin_internal() :
*   @return : 0, or an error code */
static size_t ZSTD_compressBegin_internal(ZSTD_CCtx* cctx,
                             const void* dict, size_t dictSize,
                                   ZSTD_parameters params, U64 pledgedSrcSize)

    ZSTD_parameters const params = ZSTD_getParams(compressionLevel, 0, dictSize);
    return ZSTD_compressBegin_internal(cctx, dict, dictSize, params, 0);
}


size_t ZSTD_compressBegin(ZSTD_CCtx* zc, int compressionLevel)
{
    return ZSTD_compressBegin_usingDict(zc, NULL, 0, compressionLevel);
}


/*! ZSTD_writeEpilogue() :
*   Ends a frame.

/* =====  Dictionary API  ===== */

struct ZSTD_CDict_s {
    void* dictContent;
    size_t dictContentSize;
    ZSTD_CCtx* refContext;
};  /* typedef'd tp ZSTD_CDict within "zstd.h" */

size_t ZSTD_sizeof_CDict(const ZSTD_CDict* cdict)
{
    if (cdict==NULL) return 0;   /* support sizeof on NULL */
    return ZSTD_sizeof_CCtx(cdict->refContext) + cdict->dictContentSize;
}

ZSTD_CDict* ZSTD_createCDict_advanced(const void* dict, size_t dictSize, ZSTD_parameters params, ZSTD_customMem customMem)
{
    if (!customMem.customAlloc && !customMem.customFree) customMem = defaultCustomMem;
    if (!customMem.customAlloc || !customMem.customFree) return NULL;

    {   ZSTD_CDict* const cdict = (ZSTD_CDict*) ZSTD_malloc(sizeof(ZSTD_CDict), customMem);
        void* const dictContent = ZSTD_malloc(dictSize, customMem);
        ZSTD_CCtx* const cctx = ZSTD_createCCtx_advanced(customMem);

        if (!dictContent || !cdict || !cctx) {
            ZSTD_free(dictContent, customMem);
            ZSTD_free(cdict, customMem);
            ZSTD_free(cctx, customMem);
            return NULL;
        }

        if (dictSize) {
            memcpy(dictContent, dict, dictSize);
        }
        {   size_t const errorCode = ZSTD_compressBegin_advanced(cctx, dictContent, dictSize, params, 0);
            if (ZSTD_isError(errorCode)) {
                ZSTD_free(dictContent, customMem);
                ZSTD_free(cdict, customMem);
                ZSTD_free(cctx, customMem);
                return NULL;
        }   }

        cdict->dictContent = dictContent;
        cdict->dictContentSize = dictSize;
        cdict->refContext = cctx;
        return cdict;
    }
}

ZSTD_CDict* ZSTD_createCDict(const void* dict, size_t dictSize, int compressionLevel)
{
    ZSTD_customMem const allocator = { NULL, NULL, NULL };
    ZSTD_parameters params = ZSTD_getParams(compressionLevel, 0, dictSize);
    params.fParams.contentSizeFlag = 1;
    return ZSTD_createCDict_advanced(dict, dictSize, params, allocator);
}

size_t ZSTD_freeCDict(ZSTD_CDict* cdict)
{
    if (cdict==NULL) return 0;   /* support free on NULL */
    {   ZSTD_customMem const cMem = cdict->refContext->customMem;
        ZSTD_freeCCtx(cdict->refContext);
        ZSTD_free(cdict->dictContent, cMem);
        ZSTD_free(cdict, cMem);
        return 0;
    }
}

static ZSTD_parameters ZSTD_getParamsFromCDict(const ZSTD_CDict* cdict) {
    return ZSTD_getParamsFromCCtx(cdict->refContext);
}

size_t ZSTD_compressBegin_usingCDict(ZSTD_CCtx* cctx, const ZSTD_CDict* cdict, U64 pledgedSrcSize)
{
    if (cdict->dictContentSize) CHECK_F(ZSTD_copyCCtx(cctx, cdict->refContext, pledgedSrcSize))
    else CHECK_F(ZSTD_compressBegin_advanced(cctx, NULL, 0, cdict->refContext->params, pledgedSrcSize));
    return 0;
}

size_t ZSTD_CStreamInSize(void)  { return ZSTD_BLOCKSIZE_ABSOLUTEMAX; }
size_t ZSTD_CStreamOutSize(void) { return ZSTD_compressBound(ZSTD_BLOCKSIZE_ABSOLUTEMAX) + ZSTD_blockHeaderSize + 4 /* 32-bits hash */ ; }

size_t ZSTD_resetCStream(ZSTD_CStream* zcs, unsigned long long pledgedSrcSize)
{
    if (zcs->inBuffSize==0) return ERROR(stage_wrong);   /* zcs has not been init at least once */

    if (zcs->cdict) CHECK_F(ZSTD_compressBegin_usingCDict(zcs->cctx, zcs->cdict, pledgedSrcSize))
    else CHECK_F(ZSTD_compressBegin_advanced(zcs->cctx, NULL, 0, zcs->params, pledgedSrcSize));

    zcs->inToCompress = 0;

        ZSTD_free(zcs->outBuff, zcs->customMem);
        zcs->outBuff = (char*) ZSTD_malloc(zcs->outBuffSize, zcs->customMem);
        if (zcs->outBuff == NULL) return ERROR(memory_allocation);
    }

    if (dict) {
        ZSTD_freeCDict(zcs->cdictLocal);
        zcs->cdictLocal = ZSTD_createCDict_advanced(dict, dictSize, params, zcs->customMem);
        if (zcs->cdictLocal == NULL) return ERROR(memory_allocation);
        zcs->cdict = zcs->cdictLocal;
    } else zcs->cdict = NULL;

    zcs->checksum = params.fParams.checksumFlag > 0;

size_t ZSTD_initCStream_usingCDict(ZSTD_CStream* zcs, const ZSTD_CDict* cdict)
{
    ZSTD_parameters const params = ZSTD_getParamsFromCDict(cdict);
    size_t const initError =  ZSTD_initCStream_advanced(zcs, NULL, 0, params, 0);
    zcs->cdict = cdict;
    return initError;
}

size_t ZSTD_initCStream_usingDict(ZSTD_CStream* zcs, const void* dict, size_t dictSize, int compressionLevel)
{

    return ZSTD_initCStream_advanced(zcs, dict, dictSize, params, 0);
}

size_t ZSTD_initCStream_srcSize(ZSTD_CStream* zcs, int compressionLevel, unsigned long long pledgedSrcSize)
{
    ZSTD_parameters const params = ZSTD_getParams(compressionLevel, pledgedSrcSize, 0);
    return ZSTD_initCStream_advanced(zcs, NULL, 0, params, pledgedSrcSize);
}

size_t ZSTD_initCStream(ZSTD_CStream* zcs, int compressionLevel)
{

30924:c32454d69b85

/*-*************************************
*  Context memory management
***************************************/
struct ZSTD_CCtx_s {
    const BYTE* nextSrc;    /* next block here to continue on current prefix */
    const BYTE* base;       /* All regular indexes relative to this position */
    const BYTE* dictBase;   /* extDict indexes relative to this position */
    U32   dictLimit;        /* below that point, need extDict */
    U32   lowLimit;         /* below that point, no more data */
    U32   nextToUpdate;     /* index from which to continue dictionary update */
    U32   nextToUpdate3;    /* index from which to continue dictionary update */
    U32   hashLog3;         /* dispatch table : larger == faster, more memory */
    U32   loadedDictEnd;    /* index of end of dictionary */
    U32   forceWindow;      /* force back-references to respect limit of 1<<wLog, even for dictionary */
    ZSTD_compressionStage_e stage;
    U32   rep[ZSTD_REP_NUM];
    U32   repToConfirm[ZSTD_REP_NUM];
    U32   dictID;
    ZSTD_parameters params;
    void* workSpace;
    size_t workSpaceSize;
    size_t blockSize;

    if (!customMem.customAlloc || !customMem.customFree) return NULL;

    cctx = (ZSTD_CCtx*) ZSTD_malloc(sizeof(ZSTD_CCtx), customMem);
    if (!cctx) return NULL;
    memset(cctx, 0, sizeof(ZSTD_CCtx));
    cctx->customMem = customMem;
    return cctx;
}

size_t ZSTD_freeCCtx(ZSTD_CCtx* cctx)
{

size_t ZSTD_sizeof_CCtx(const ZSTD_CCtx* cctx)
{
    if (cctx==NULL) return 0;   /* support sizeof on NULL */
    return sizeof(*cctx) + cctx->workSpaceSize;
}

size_t ZSTD_setCCtxParameter(ZSTD_CCtx* cctx, ZSTD_CCtxParameter param, unsigned value)
{
    switch(param)
    {
    case ZSTD_p_forceWindow : cctx->forceWindow = value>0; cctx->loadedDictEnd = 0; return 0;
    default: return ERROR(parameter_unknown);
    }
}

const seqStore_t* ZSTD_getSeqStore(const ZSTD_CCtx* ctx)   /* hidden interface */
{
    return &(ctx->seqStore);

        return 0;
    }
}

/* ZSTD_invalidateRepCodes() :
 * ensures next compression will not use repcodes from previous block.
 * Note : only works with regular variant;
 *        do not use with extDict variant ! */
void ZSTD_invalidateRepCodes(ZSTD_CCtx* cctx) {
    int i;
    for (i=0; i<ZSTD_REP_NUM; i++) cctx->rep[i] = 0;
}

/*! ZSTD_copyCCtx() :
*   Duplicate an existing context `srcCCtx` into another one `dstCCtx`.
*   Only works during stage ZSTDcs_init (i.e. after creation, but before first call to ZSTD_compressContinue()).
*   @return : 0, or an error code */

    { size_t const minGain = ZSTD_minGain(srcSize);
      size_t const maxCSize = srcSize - minGain;
      if ((size_t)(op-ostart) >= maxCSize) return 0; }

    /* confirm repcodes */
    { int i; for (i=0; i<ZSTD_REP_NUM; i++) zc->rep[i] = zc->repToConfirm[i]; }

    return op - ostart;
}


#if 0 /* for debug */
#  define STORESEQ_DEBUG
#include <stdio.h>   /* fprintf */
U32 g_startDebug = 0;
const BYTE* g_start = NULL;
#endif

/*! ZSTD_storeSeq() :
    Store a sequence (literal length, literals, offset code and match length code) into seqStore_t.
    `offsetCode` : distance to match, or 0 == repCode.
    `matchCode` : matchLength - MINMATCH
*/
MEM_STATIC void ZSTD_storeSeq(seqStore_t* seqStorePtr, size_t litLength, const void* literals, U32 offsetCode, size_t matchCode)
{
#ifdef STORESEQ_DEBUG
    if (g_startDebug) {
        const U32 pos = (U32)((const BYTE*)literals - g_start);
        if (g_start==NULL) g_start = (const BYTE*)literals;
        if ((pos > 1895000) && (pos < 1895300))
            fprintf(stderr, "Cpos %6u :%5u literals & match %3u bytes at distance %6u \n",
                   pos, (U32)litLength, (U32)matchCode+MINMATCH, (U32)offsetCode);
    }
#endif
    /* copy Literals */
    ZSTD_wildcopy(seqStorePtr->lit, literals, litLength);
    seqStorePtr->lit += litLength;

                anchor = ip;
                continue;   /* faster when present ... (?) */
    }   }   }

    /* save reps for next block */
    cctx->repToConfirm[0] = offset_1 ? offset_1 : offsetSaved;
    cctx->repToConfirm[1] = offset_2 ? offset_2 : offsetSaved;

    /* Last Literals */
    {   size_t const lastLLSize = iend - anchor;
        memcpy(seqStorePtr->lit, anchor, lastLLSize);
        seqStorePtr->lit += lastLLSize;

                }
                break;
    }   }   }

    /* save reps for next block */
    ctx->repToConfirm[0] = offset_1; ctx->repToConfirm[1] = offset_2;

    /* Last Literals */
    {   size_t const lastLLSize = iend - anchor;
        memcpy(seqStorePtr->lit, anchor, lastLLSize);
        seqStorePtr->lit += lastLLSize;

                anchor = ip;
                continue;   /* faster when present ... (?) */
    }   }   }

    /* save reps for next block */
    cctx->repToConfirm[0] = offset_1 ? offset_1 : offsetSaved;
    cctx->repToConfirm[1] = offset_2 ? offset_2 : offsetSaved;

    /* Last Literals */
    {   size_t const lastLLSize = iend - anchor;
        memcpy(seqStorePtr->lit, anchor, lastLLSize);
        seqStorePtr->lit += lastLLSize;

                }
                break;
    }   }   }

    /* save reps for next block */
    ctx->repToConfirm[0] = offset_1; ctx->repToConfirm[1] = offset_2;

    /* Last Literals */
    {   size_t const lastLLSize = iend - anchor;
        memcpy(seqStorePtr->lit, anchor, lastLLSize);
        seqStorePtr->lit += lastLLSize;

            anchor = ip;
            continue;   /* faster when present ... (?) */
    }   }

    /* Save reps for next block */
    ctx->repToConfirm[0] = offset_1 ? offset_1 : savedOffset;
    ctx->repToConfirm[1] = offset_2 ? offset_2 : savedOffset;

    /* Last Literals */
    {   size_t const lastLLSize = iend - anchor;
        memcpy(seqStorePtr->lit, anchor, lastLLSize);
        seqStorePtr->lit += lastLLSize;

            }
            break;
    }   }

    /* Save reps for next block */
    ctx->repToConfirm[0] = offset_1; ctx->repToConfirm[1] = offset_2;

    /* Last Literals */
    {   size_t const lastLLSize = iend - anchor;
        memcpy(seqStorePtr->lit, anchor, lastLLSize);
        seqStorePtr->lit += lastLLSize;

        cctx->lowLimit = lowLimitMax;
    }

    cctx->nextSrc = ip + srcSize;

    if (srcSize) {
        size_t const cSize = frame ?
                             ZSTD_compress_generic (cctx, dst, dstCapacity, src, srcSize, lastFrameChunk) :
                             ZSTD_compressBlock_internal (cctx, dst, dstCapacity, src, srcSize);
        if (ZSTD_isError(cSize)) return cSize;
        return cSize + fhSize;
    } else
        return fhSize;
}


size_t ZSTD_compressContinue (ZSTD_CCtx* cctx,
                              void* dst, size_t dstCapacity,

    zc->lowLimit = zc->dictLimit;
    zc->dictLimit = (U32)(zc->nextSrc - zc->base);
    zc->dictBase = zc->base;
    zc->base += ip - zc->nextSrc;
    zc->nextToUpdate = zc->dictLimit;
    zc->loadedDictEnd = zc->forceWindow ? 0 : (U32)(iend - zc->base);

    zc->nextSrc = iend;
    if (srcSize <= HASH_READ_SIZE) return 0;

    switch(zc->params.cParams.strategy)

        CHECK_E(FSE_buildCTable_wksp(cctx->litlengthCTable, litlengthNCount, litlengthMaxValue, litlengthLog, scratchBuffer, sizeof(scratchBuffer)), dictionary_corrupted);
        dictPtr += litlengthHeaderSize;
    }

    if (dictPtr+12 > dictEnd) return ERROR(dictionary_corrupted);
    cctx->rep[0] = MEM_readLE32(dictPtr+0); if (cctx->rep[0] == 0 || cctx->rep[0] >= dictSize) return ERROR(dictionary_corrupted);
    cctx->rep[1] = MEM_readLE32(dictPtr+4); if (cctx->rep[1] == 0 || cctx->rep[1] >= dictSize) return ERROR(dictionary_corrupted);
    cctx->rep[2] = MEM_readLE32(dictPtr+8); if (cctx->rep[2] == 0 || cctx->rep[2] >= dictSize) return ERROR(dictionary_corrupted);
    dictPtr += 12;

    {   U32 offcodeMax = MaxOff;
        if ((size_t)(dictEnd - dictPtr) <= ((U32)-1) - 128 KB) {
            U32 const maxOffset = (U32)(dictEnd - dictPtr) + 128 KB; /* The maximum offset that must be supported */

        if (ZSTD_isError(loadError)) return loadError;
        return ZSTD_loadDictionaryContent(zc, (const char*)dict+eSize, dictSize-eSize);
    }
}

/*! ZSTD_compressBegin_internal() :
*   @return : 0, or an error code */
static size_t ZSTD_compressBegin_internal(ZSTD_CCtx* cctx,
                             const void* dict, size_t dictSize,
                                   ZSTD_parameters params, U64 pledgedSrcSize)

    ZSTD_parameters const params = ZSTD_getParams(compressionLevel, 0, dictSize);
    return ZSTD_compressBegin_internal(cctx, dict, dictSize, params, 0);
}


size_t ZSTD_compressBegin(ZSTD_CCtx* cctx, int compressionLevel)
{
    return ZSTD_compressBegin_usingDict(cctx, NULL, 0, compressionLevel);
}


/*! ZSTD_writeEpilogue() :
*   Ends a frame.

/* =====  Dictionary API  ===== */

struct ZSTD_CDict_s {
    void* dictBuffer;
    const void* dictContent;
    size_t dictContentSize;
    ZSTD_CCtx* refContext;
};  /* typedef'd tp ZSTD_CDict within "zstd.h" */

size_t ZSTD_sizeof_CDict(const ZSTD_CDict* cdict)
{
    if (cdict==NULL) return 0;   /* support sizeof on NULL */
    return ZSTD_sizeof_CCtx(cdict->refContext) + (cdict->dictBuffer ? cdict->dictContentSize : 0) + sizeof(*cdict);
}

ZSTD_CDict* ZSTD_createCDict_advanced(const void* dictBuffer, size_t dictSize, unsigned byReference,
                                      ZSTD_parameters params, ZSTD_customMem customMem)
{
    if (!customMem.customAlloc && !customMem.customFree) customMem = defaultCustomMem;
    if (!customMem.customAlloc || !customMem.customFree) return NULL;

    {   ZSTD_CDict* const cdict = (ZSTD_CDict*) ZSTD_malloc(sizeof(ZSTD_CDict), customMem);
        ZSTD_CCtx* const cctx = ZSTD_createCCtx_advanced(customMem);

        if (!cdict || !cctx) {
            ZSTD_free(cdict, customMem);
            ZSTD_free(cctx, customMem);
            return NULL;
        }

        if ((byReference) || (!dictBuffer) || (!dictSize)) {
            cdict->dictBuffer = NULL;
            cdict->dictContent = dictBuffer;
        } else {
            void* const internalBuffer = ZSTD_malloc(dictSize, customMem);
            if (!internalBuffer) { ZSTD_free(cctx, customMem); ZSTD_free(cdict, customMem); return NULL; }
            memcpy(internalBuffer, dictBuffer, dictSize);
            cdict->dictBuffer = internalBuffer;
            cdict->dictContent = internalBuffer;
        }

        {   size_t const errorCode = ZSTD_compressBegin_advanced(cctx, cdict->dictContent, dictSize, params, 0);
            if (ZSTD_isError(errorCode)) {
                ZSTD_free(cdict->dictBuffer, customMem);
                ZSTD_free(cctx, customMem);
                ZSTD_free(cdict, customMem);
                return NULL;
        }   }

        cdict->refContext = cctx;
        cdict->dictContentSize = dictSize;
        return cdict;
    }
}

ZSTD_CDict* ZSTD_createCDict(const void* dict, size_t dictSize, int compressionLevel)
{
    ZSTD_customMem const allocator = { NULL, NULL, NULL };
    ZSTD_parameters params = ZSTD_getParams(compressionLevel, 0, dictSize);
    params.fParams.contentSizeFlag = 1;
    return ZSTD_createCDict_advanced(dict, dictSize, 0, params, allocator);
}

ZSTD_CDict* ZSTD_createCDict_byReference(const void* dict, size_t dictSize, int compressionLevel)
{
    ZSTD_customMem const allocator = { NULL, NULL, NULL };
    ZSTD_parameters params = ZSTD_getParams(compressionLevel, 0, dictSize);
    params.fParams.contentSizeFlag = 1;
    return ZSTD_createCDict_advanced(dict, dictSize, 1, params, allocator);
}

size_t ZSTD_freeCDict(ZSTD_CDict* cdict)
{
    if (cdict==NULL) return 0;   /* support free on NULL */
    {   ZSTD_customMem const cMem = cdict->refContext->customMem;
        ZSTD_freeCCtx(cdict->refContext);
        ZSTD_free(cdict->dictBuffer, cMem);
        ZSTD_free(cdict, cMem);
        return 0;
    }
}

static ZSTD_parameters ZSTD_getParamsFromCDict(const ZSTD_CDict* cdict) {
    return ZSTD_getParamsFromCCtx(cdict->refContext);
}

size_t ZSTD_compressBegin_usingCDict(ZSTD_CCtx* cctx, const ZSTD_CDict* cdict, unsigned long long pledgedSrcSize)
{
    if (cdict->dictContentSize) CHECK_F(ZSTD_copyCCtx(cctx, cdict->refContext, pledgedSrcSize))
    else CHECK_F(ZSTD_compressBegin_advanced(cctx, NULL, 0, cdict->refContext->params, pledgedSrcSize));
    return 0;
}

size_t ZSTD_CStreamInSize(void)  { return ZSTD_BLOCKSIZE_ABSOLUTEMAX; }
size_t ZSTD_CStreamOutSize(void) { return ZSTD_compressBound(ZSTD_BLOCKSIZE_ABSOLUTEMAX) + ZSTD_blockHeaderSize + 4 /* 32-bits hash */ ; }

size_t ZSTD_resetCStream(ZSTD_CStream* zcs, unsigned long long pledgedSrcSize)
{
    if (zcs->inBuffSize==0) return ERROR(stage_wrong);   /* zcs has not been init at least once => can't reset */

    if (zcs->cdict) CHECK_F(ZSTD_compressBegin_usingCDict(zcs->cctx, zcs->cdict, pledgedSrcSize))
    else CHECK_F(ZSTD_compressBegin_advanced(zcs->cctx, NULL, 0, zcs->params, pledgedSrcSize));

    zcs->inToCompress = 0;

        ZSTD_free(zcs->outBuff, zcs->customMem);
        zcs->outBuff = (char*) ZSTD_malloc(zcs->outBuffSize, zcs->customMem);
        if (zcs->outBuff == NULL) return ERROR(memory_allocation);
    }

    if (dict && dictSize >= 8) {
        ZSTD_freeCDict(zcs->cdictLocal);
        zcs->cdictLocal = ZSTD_createCDict_advanced(dict, dictSize, 0, params, zcs->customMem);
        if (zcs->cdictLocal == NULL) return ERROR(memory_allocation);
        zcs->cdict = zcs->cdictLocal;
    } else zcs->cdict = NULL;

    zcs->checksum = params.fParams.checksumFlag > 0;

size_t ZSTD_initCStream_usingCDict(ZSTD_CStream* zcs, const ZSTD_CDict* cdict)
{
    ZSTD_parameters const params = ZSTD_getParamsFromCDict(cdict);
    size_t const initError =  ZSTD_initCStream_advanced(zcs, NULL, 0, params, 0);
    zcs->cdict = cdict;
    zcs->cctx->dictID = params.fParams.noDictIDFlag ? 0 : cdict->refContext->dictID;
    return initError;
}

size_t ZSTD_initCStream_usingDict(ZSTD_CStream* zcs, const void* dict, size_t dictSize, int compressionLevel)
{

    return ZSTD_initCStream_advanced(zcs, dict, dictSize, params, 0);
}

size_t ZSTD_initCStream_srcSize(ZSTD_CStream* zcs, int compressionLevel, unsigned long long pledgedSrcSize)
{
    ZSTD_parameters params = ZSTD_getParams(compressionLevel, pledgedSrcSize, 0);
    if (pledgedSrcSize) params.fParams.contentSizeFlag = 1;
    return ZSTD_initCStream_advanced(zcs, NULL, 0, params, pledgedSrcSize);
}

size_t ZSTD_initCStream(ZSTD_CStream* zcs, int compressionLevel)
{