Added ZDICT_getDictID()

This commit is contained in:
Yann Collet 2016-08-19 14:23:58 +02:00
parent b571a0eab4
commit da3fbcb302
3 changed files with 14 additions and 0 deletions

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@ -126,6 +126,13 @@ unsigned ZDICT_isError(size_t errorCode) { return ERR_isError(errorCode); }
const char* ZDICT_getErrorName(size_t errorCode) { return ERR_getErrorName(errorCode); }
unsigned ZDICT_getDictID(const void* dictBuffer, size_t dictSize)
{
if (dictSize < 8) return 0;
if (MEM_readLE32(dictBuffer) != ZSTD_DICT_MAGIC) return 0;
return MEM_readLE32((const char*)dictBuffer + 4);
}
/*-********************************************************
* Dictionary training functions

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@ -68,6 +68,7 @@ ZDICTLIB_API size_t ZDICT_trainFromBuffer(void* dictBuffer, size_t dictBufferCap
/*====== Helper functions ======*/
ZDICTLIB_API unsigned ZDICT_getDictID(const void* dictBuffer, size_t dictSize); /**< extracts dictID; @return zero if error (not a valid dictionary) */
ZDICTLIB_API unsigned ZDICT_isError(size_t errorCode);
ZDICTLIB_API const char* ZDICT_getErrorName(size_t errorCode);

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@ -272,6 +272,12 @@ static int basicUnitTests(U32 seed, double compressibility)
if (ZDICT_isError(dictSize)) goto _output_error;
DISPLAYLEVEL(4, "OK, created dictionary of size %u \n", (U32)dictSize);
DISPLAYLEVEL(4, "test%3i : check dictID : ", testNb++);
{ U32 const dictID = ZDICT_getDictID(dictBuffer, dictSize);
if (dictID==0) goto _output_error;
DISPLAYLEVEL(4, "OK : %u \n", dictID);
}
DISPLAYLEVEL(4, "test%3i : compress with dictionary : ", testNb++);
cSize = ZSTD_compress_usingDict(cctx, compressedBuffer, ZSTD_compressBound(CNBuffSize),
CNBuffer, CNBuffSize,