contrib/python-zstandard/zstd/decompress/zstd_decompress.c

30923:5b60464efbde

                           const void* dict, size_t dictSize)
{
#if defined(ZSTD_LEGACY_SUPPORT) && (ZSTD_LEGACY_SUPPORT==1)
    if (ZSTD_isLegacy(src, srcSize)) return ZSTD_decompressLegacy(dst, dstCapacity, src, srcSize, dict, dictSize);
#endif
    ZSTD_decompressBegin_usingDict(dctx, dict, dictSize);
    ZSTD_checkContinuity(dctx, dst);
    return ZSTD_decompressFrame(dctx, dst, dstCapacity, src, srcSize);
}

        CHECK_E(FSE_buildDTable(dctx->LLTable, litlengthNCount, litlengthMaxValue, litlengthLog), dictionary_corrupted);
        dictPtr += litlengthHeaderSize;
    }

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

    dctx->litEntropy = dctx->fseEntropy = 1;
    return dictPtr - (const BYTE*)dict;
}

/* ======   ZSTD_DDict   ====== */

struct ZSTD_DDict_s {
    void* dict;
    size_t dictSize;
    ZSTD_DCtx* refContext;
};  /* typedef'd to ZSTD_DDict within "zstd.h" */

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

    {   ZSTD_DDict* const ddict = (ZSTD_DDict*) ZSTD_malloc(sizeof(ZSTD_DDict), customMem);
        void* const dictContent = ZSTD_malloc(dictSize, customMem);
        ZSTD_DCtx* const dctx = ZSTD_createDCtx_advanced(customMem);

        if (!dictContent || !ddict || !dctx) {
            ZSTD_free(dictContent, customMem);
            ZSTD_free(ddict, customMem);
            ZSTD_free(dctx, customMem);
            return NULL;
        }

        if (dictSize) {
            memcpy(dictContent, dict, dictSize);
        }
        {   size_t const errorCode = ZSTD_decompressBegin_usingDict(dctx, dictContent, dictSize);
            if (ZSTD_isError(errorCode)) {
                ZSTD_free(dictContent, customMem);
                ZSTD_free(ddict, customMem);
                ZSTD_free(dctx, customMem);
                return NULL;
        }   }

        ddict->dict = dictContent;
        ddict->dictSize = dictSize;
        ddict->refContext = dctx;
        return ddict;
    }
}

*   Create a digested dictionary, ready to start decompression without startup delay.
*   `dict` can be released after `ZSTD_DDict` creation */
ZSTD_DDict* ZSTD_createDDict(const void* dict, size_t dictSize)
{
    ZSTD_customMem const allocator = { NULL, NULL, NULL };
    return ZSTD_createDDict_advanced(dict, dictSize, allocator);
}

size_t ZSTD_freeDDict(ZSTD_DDict* ddict)
{
    if (ddict==NULL) return 0;   /* support free on NULL */
    {   ZSTD_customMem const cMem = ddict->refContext->customMem;
        ZSTD_freeDCtx(ddict->refContext);
        ZSTD_free(ddict->dict, cMem);
        ZSTD_free(ddict, cMem);
        return 0;
    }
}

size_t ZSTD_sizeof_DDict(const ZSTD_DDict* ddict)
{
    if (ddict==NULL) return 0;   /* support sizeof on NULL */
    return sizeof(*ddict) + sizeof(ddict->refContext) + ddict->dictSize;
}

/*! ZSTD_getDictID_fromDict() :
 *  Provides the dictID stored within dictionary.
 *  if @return == 0, the dictionary is not conformant with Zstandard specification.

 *  If @return == 0, the dictionary is not conformant to Zstandard specification, or empty.
 *  Non-conformant dictionaries can still be loaded, but as content-only dictionaries. */
unsigned ZSTD_getDictID_fromDDict(const ZSTD_DDict* ddict)
{
    if (ddict==NULL) return 0;
    return ZSTD_getDictID_fromDict(ddict->dict, ddict->dictSize);
}

/*! ZSTD_getDictID_fromFrame() :
 *  Provides the dictID required to decompressed the frame stored within `src`.
 *  If @return == 0, the dictID could not be decoded.

                                  void* dst, size_t dstCapacity,
                            const void* src, size_t srcSize,
                            const ZSTD_DDict* ddict)
{
#if defined(ZSTD_LEGACY_SUPPORT) && (ZSTD_LEGACY_SUPPORT==1)
    if (ZSTD_isLegacy(src, srcSize)) return ZSTD_decompressLegacy(dst, dstCapacity, src, srcSize, ddict->dict, ddict->dictSize);
#endif
    ZSTD_refDCtx(dctx, ddict->refContext);
    ZSTD_checkContinuity(dctx, dst);
    return ZSTD_decompressFrame(dctx, dst, dstCapacity, src, srcSize);
}

size_t ZSTD_initDStream_usingDict(ZSTD_DStream* zds, const void* dict, size_t dictSize)
{
    zds->stage = zdss_loadHeader;
    zds->lhSize = zds->inPos = zds->outStart = zds->outEnd = 0;
    ZSTD_freeDDict(zds->ddictLocal);
    if (dict) {
        zds->ddictLocal = ZSTD_createDDict(dict, dictSize);
        if (zds->ddictLocal == NULL) return ERROR(memory_allocation);
    } else zds->ddictLocal = NULL;
    zds->ddict = zds->ddictLocal;
    zds->legacyVersion = 0;

                                ZSTD_DStreamParameter_e paramType, unsigned paramValue)
{
    switch(paramType)
    {
        default : return ERROR(parameter_unknown);
        case ZSTDdsp_maxWindowSize : zds->maxWindowSize = paramValue ? paramValue : (U32)(-1); break;
    }
    return 0;
}

            {   size_t const hSize = ZSTD_getFrameParams(&zds->fParams, zds->headerBuffer, zds->lhSize);
                if (ZSTD_isError(hSize))
#if defined(ZSTD_LEGACY_SUPPORT) && (ZSTD_LEGACY_SUPPORT>=1)
                {   U32 const legacyVersion = ZSTD_isLegacy(istart, iend-istart);
                    if (legacyVersion) {
                        const void* const dict = zds->ddict ? zds->ddict->dict : NULL;
                        size_t const dictSize = zds->ddict ? zds->ddict->dictSize : 0;
                        CHECK_F(ZSTD_initLegacyStream(&zds->legacyContext, zds->previousLegacyVersion, legacyVersion,
                                                       dict, dictSize));
                        zds->legacyVersion = zds->previousLegacyVersion = legacyVersion;
                        return ZSTD_decompressLegacyStream(zds->legacyContext, zds->legacyVersion, output, input);

30924:c32454d69b85

                           const void* dict, size_t dictSize)
{
#if defined(ZSTD_LEGACY_SUPPORT) && (ZSTD_LEGACY_SUPPORT==1)
    if (ZSTD_isLegacy(src, srcSize)) return ZSTD_decompressLegacy(dst, dstCapacity, src, srcSize, dict, dictSize);
#endif
    CHECK_F(ZSTD_decompressBegin_usingDict(dctx, dict, dictSize));
    ZSTD_checkContinuity(dctx, dst);
    return ZSTD_decompressFrame(dctx, dst, dstCapacity, src, srcSize);
}

        CHECK_E(FSE_buildDTable(dctx->LLTable, litlengthNCount, litlengthMaxValue, litlengthLog), dictionary_corrupted);
        dictPtr += litlengthHeaderSize;
    }

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

    dctx->litEntropy = dctx->fseEntropy = 1;
    return dictPtr - (const BYTE*)dict;
}

/* ======   ZSTD_DDict   ====== */

struct ZSTD_DDict_s {
    void* dictBuffer;
    const void* dictContent;
    size_t dictSize;
    ZSTD_DCtx* refContext;
};  /* typedef'd to ZSTD_DDict within "zstd.h" */

ZSTD_DDict* ZSTD_createDDict_advanced(const void* dict, size_t dictSize, unsigned byReference, ZSTD_customMem customMem)
{
    if (!customMem.customAlloc && !customMem.customFree) customMem = defaultCustomMem;
    if (!customMem.customAlloc || !customMem.customFree) return NULL;

    {   ZSTD_DDict* const ddict = (ZSTD_DDict*) ZSTD_malloc(sizeof(ZSTD_DDict), customMem);
        ZSTD_DCtx* const dctx = ZSTD_createDCtx_advanced(customMem);

        if (!ddict || !dctx) {
            ZSTD_free(ddict, customMem);
            ZSTD_free(dctx, customMem);
            return NULL;
        }

        if ((byReference) || (!dict) || (!dictSize)) {
            ddict->dictBuffer = NULL;
            ddict->dictContent = dict;
        } else {
            void* const internalBuffer = ZSTD_malloc(dictSize, customMem);
            if (!internalBuffer) { ZSTD_free(dctx, customMem); ZSTD_free(ddict, customMem); return NULL; }
            memcpy(internalBuffer, dict, dictSize);
            ddict->dictBuffer = internalBuffer;
            ddict->dictContent = internalBuffer;
        }
        {   size_t const errorCode = ZSTD_decompressBegin_usingDict(dctx, ddict->dictContent, dictSize);
            if (ZSTD_isError(errorCode)) {
                ZSTD_free(ddict->dictBuffer, customMem);
                ZSTD_free(ddict, customMem);
                ZSTD_free(dctx, customMem);
                return NULL;
        }   }

        ddict->dictSize = dictSize;
        ddict->refContext = dctx;
        return ddict;
    }
}

*   Create a digested dictionary, ready to start decompression without startup delay.
*   `dict` can be released after `ZSTD_DDict` creation */
ZSTD_DDict* ZSTD_createDDict(const void* dict, size_t dictSize)
{
    ZSTD_customMem const allocator = { NULL, NULL, NULL };
    return ZSTD_createDDict_advanced(dict, dictSize, 0, allocator);
}


/*! ZSTD_createDDict_byReference() :
 *  Create a digested dictionary, ready to start decompression operation without startup delay.
 *  Dictionary content is simply referenced, and therefore stays in dictBuffer.
 *  It is important that dictBuffer outlives DDict, it must remain read accessible throughout the lifetime of DDict */
ZSTD_DDict* ZSTD_createDDict_byReference(const void* dictBuffer, size_t dictSize)
{
    ZSTD_customMem const allocator = { NULL, NULL, NULL };
    return ZSTD_createDDict_advanced(dictBuffer, dictSize, 1, allocator);
}


size_t ZSTD_freeDDict(ZSTD_DDict* ddict)
{
    if (ddict==NULL) return 0;   /* support free on NULL */
    {   ZSTD_customMem const cMem = ddict->refContext->customMem;
        ZSTD_freeDCtx(ddict->refContext);
        ZSTD_free(ddict->dictBuffer, cMem);
        ZSTD_free(ddict, cMem);
        return 0;
    }
}

size_t ZSTD_sizeof_DDict(const ZSTD_DDict* ddict)
{
    if (ddict==NULL) return 0;   /* support sizeof on NULL */
    return sizeof(*ddict) + ZSTD_sizeof_DCtx(ddict->refContext) + (ddict->dictBuffer ? ddict->dictSize : 0) ;
}

/*! ZSTD_getDictID_fromDict() :
 *  Provides the dictID stored within dictionary.
 *  if @return == 0, the dictionary is not conformant with Zstandard specification.

 *  If @return == 0, the dictionary is not conformant to Zstandard specification, or empty.
 *  Non-conformant dictionaries can still be loaded, but as content-only dictionaries. */
unsigned ZSTD_getDictID_fromDDict(const ZSTD_DDict* ddict)
{
    if (ddict==NULL) return 0;
    return ZSTD_getDictID_fromDict(ddict->dictContent, ddict->dictSize);
}

/*! ZSTD_getDictID_fromFrame() :
 *  Provides the dictID required to decompressed the frame stored within `src`.
 *  If @return == 0, the dictID could not be decoded.

                                  void* dst, size_t dstCapacity,
                            const void* src, size_t srcSize,
                            const ZSTD_DDict* ddict)
{
#if defined(ZSTD_LEGACY_SUPPORT) && (ZSTD_LEGACY_SUPPORT==1)
    if (ZSTD_isLegacy(src, srcSize)) return ZSTD_decompressLegacy(dst, dstCapacity, src, srcSize, ddict->dictContent, ddict->dictSize);
#endif
    ZSTD_refDCtx(dctx, ddict->refContext);
    ZSTD_checkContinuity(dctx, dst);
    return ZSTD_decompressFrame(dctx, dst, dstCapacity, src, srcSize);
}

size_t ZSTD_initDStream_usingDict(ZSTD_DStream* zds, const void* dict, size_t dictSize)
{
    zds->stage = zdss_loadHeader;
    zds->lhSize = zds->inPos = zds->outStart = zds->outEnd = 0;
    ZSTD_freeDDict(zds->ddictLocal);
    if (dict && dictSize >= 8) {
        zds->ddictLocal = ZSTD_createDDict(dict, dictSize);
        if (zds->ddictLocal == NULL) return ERROR(memory_allocation);
    } else zds->ddictLocal = NULL;
    zds->ddict = zds->ddictLocal;
    zds->legacyVersion = 0;

                                ZSTD_DStreamParameter_e paramType, unsigned paramValue)
{
    switch(paramType)
    {
        default : return ERROR(parameter_unknown);
        case DStream_p_maxWindowSize : zds->maxWindowSize = paramValue ? paramValue : (U32)(-1); break;
    }
    return 0;
}

            {   size_t const hSize = ZSTD_getFrameParams(&zds->fParams, zds->headerBuffer, zds->lhSize);
                if (ZSTD_isError(hSize))
#if defined(ZSTD_LEGACY_SUPPORT) && (ZSTD_LEGACY_SUPPORT>=1)
                {   U32 const legacyVersion = ZSTD_isLegacy(istart, iend-istart);
                    if (legacyVersion) {
                        const void* const dict = zds->ddict ? zds->ddict->dictContent : NULL;
                        size_t const dictSize = zds->ddict ? zds->ddict->dictSize : 0;
                        CHECK_F(ZSTD_initLegacyStream(&zds->legacyContext, zds->previousLegacyVersion, legacyVersion,
                                                       dict, dictSize));
                        zds->legacyVersion = zds->previousLegacyVersion = legacyVersion;
                        return ZSTD_decompressLegacyStream(zds->legacyContext, zds->legacyVersion, output, input);