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added ZDICT_finalizeDictionary()

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This commit is contained in:
Yann Collet 2016-12-22 20:18:43 +01:00
parent 9ceb49e097
commit d76d1a9ef0
3 changed files with 97 additions and 12 deletions
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3
NEWS
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@ -1,7 +1,8 @@
v1.1.3
cli : new : commands for advanced parameters, by Przemyslaw Skibinski
cli : new : advanced commands for detailed parameters, by Przemyslaw Skibinski
API : fix : all symbols properly exposed in libzstd, by Nick Terrell
API : new : ZSTD_create?Dict_byReference(), requested by Bartosz Taudul
API : new : ZDICT_finalizeDictionary()
v1.1.2
API : streaming : decompression : changed : automatic implicit reset when chain-decoding new frames without init

49
lib/dictBuilder/zdict.c
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@ -824,6 +824,55 @@ _cleanup:
}
size_t ZDICT_finalizeDictionary(void* dictBuffer, size_t dictBufferCapacity,
const void* customDictContent, size_t dictContentSize,
const void* samplesBuffer, const size_t* samplesSizes, unsigned nbSamples,
ZDICT_params_t params)
{
size_t hSize;
#define HBUFFSIZE 256
BYTE header[HBUFFSIZE];
int const compressionLevel = (params.compressionLevel <= 0) ? g_compressionLevel_default : params.compressionLevel;
U32 const notificationLevel = params.notificationLevel;
/* check conditions */
if (dictBufferCapacity <= dictContentSize) return ERROR(dstSize_tooSmall);
if (dictContentSize < ZDICT_CONTENTSIZE_MIN) return ERROR(srcSize_wrong);
if (dictBufferCapacity < ZDICT_DICTSIZE_MIN) return ERROR(dstSize_tooSmall);
/* dictionary header */
MEM_writeLE32(header, ZSTD_DICT_MAGIC);
{ U64 const randomID = XXH64(customDictContent, dictContentSize, 0);
U32 const compliantID = (randomID % ((1U<<31)-32768)) + 32768;
U32 const dictID = params.dictID ? params.dictID : compliantID;
MEM_writeLE32(header+4, dictID);
}
hSize = 8;
/* entropy tables */
DISPLAYLEVEL(2, "\r%70s\r", ""); /* clean display line */
DISPLAYLEVEL(2, "statistics ... \n");
{ size_t const eSize = ZDICT_analyzeEntropy(header+hSize, HBUFFSIZE-hSize,
compressionLevel,
samplesBuffer, samplesSizes, nbSamples,
customDictContent, dictContentSize,
notificationLevel);
if (ZDICT_isError(eSize)) return eSize;
hSize += eSize;
}
/* copy elements in final buffer ; note : src and dst buffer can overlap */
if (hSize + dictContentSize < dictBufferCapacity) dictContentSize = dictBufferCapacity - hSize;
{ size_t const dictSize = hSize + dictContentSize;
char* dictEnd = (char*)dictBuffer + dictSize;
memmove(dictEnd - dictContentSize, customDictContent, dictContentSize);
memcpy(dictBuffer, header, hSize);
return dictSize;
}
}
size_t ZDICT_addEntropyTablesFromBuffer_advanced(void* dictBuffer, size_t dictContentSize, size_t dictBufferCapacity,
const void* samplesBuffer, const size_t* samplesSizes, unsigned nbSamples,
ZDICT_params_t params)

57
lib/dictBuilder/zdict.h
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@ -87,22 +87,57 @@ ZDICTLIB_API size_t ZDICT_trainFromBuffer_advanced(void* dictBuffer, size_t dict
ZDICT_params_t parameters);
/*! ZDICT_addEntropyTablesFromBuffer() :
/*! ZDICT_finalizeDictionary() :
Given a custom content as a basis for dictionary, and a set of samples,
finalize dictionary by adding headers and statistics.
Given a content-only dictionary (built using any 3rd party algorithm),
add entropy tables computed from an array of samples.
Samples must be stored concatenated in a flat buffer `samplesBuffer`,
supplied with an array of sizes `samplesSizes`, providing the size of each sample in order.
The input dictionary content must be stored *at the end* of `dictBuffer`.
Its size is `dictContentSize`.
The resulting dictionary with added entropy tables will be *written back to `dictBuffer`*,
starting from its beginning.
@return : size of dictionary stored into `dictBuffer` (<= `dictBufferCapacity`).
*/
ZDICTLIB_API size_t ZDICT_addEntropyTablesFromBuffer(void* dictBuffer, size_t dictContentSize, size_t dictBufferCapacity,
const void* samplesBuffer, const size_t* samplesSizes, unsigned nbSamples);
dictContentSize must be > ZDICT_CONTENTSIZE_MIN bytes.
maxDictSize must be > dictContentSize, and must be > ZDICT_DICTSIZE_MIN bytes.
@return : size of dictionary stored into `dictBuffer` (<= `dictBufferCapacity`),
or an error code, which can be tested by ZDICT_isError().
note : ZDICT_finalizeDictionary() will push notifications into stderr if instructed to, using notificationLevel>0.
note 2 : dictBuffer and customDictContent can overlap
*/
#define ZDICT_CONTENTSIZE_MIN 256
#define ZDICT_DICTSIZE_MIN 512
ZDICTLIB_API size_t ZDICT_finalizeDictionary(void* dictBuffer, size_t dictBufferCapacity,
const void* customDictContent, size_t dictContentSize,
const void* samplesBuffer, const size_t* samplesSizes, unsigned nbSamples,
ZDICT_params_t parameters);
/* Deprecation warnings */
/* It is generally possible to disable deprecation warnings from compiler,
for example with -Wno-deprecated-declarations for gcc
or _CRT_SECURE_NO_WARNINGS in Visual.
Otherwise, it's also possible to manually define ZDICT_DISABLE_DEPRECATE_WARNINGS */
#ifdef ZDICT_DISABLE_DEPRECATE_WARNINGS
# define ZDICT_DEPRECATED(message) /* disable deprecation warnings */
#else
# define ZDICT_GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__)
# if defined (__cplusplus) && (__cplusplus >= 201402) /* C++14 or greater */
# define ZDICT_DEPRECATED(message) [[deprecated(message)]]
# elif (ZDICT_GCC_VERSION >= 405) || defined(__clang__)
# define ZDICT_DEPRECATED(message) __attribute__((deprecated(message)))
# elif (ZDICT_GCC_VERSION >= 301)
# define ZDICT_DEPRECATED(message) __attribute__((deprecated))
# elif defined(_MSC_VER)
# define ZDICT_DEPRECATED(message) __declspec(deprecated(message))
# else
# pragma message("WARNING: You need to implement ZDICT_DEPRECATED for this compiler")
# define ZDICT_DEPRECATED(message)
# endif
#endif /* ZDICT_DISABLE_DEPRECATE_WARNINGS */
ZDICT_DEPRECATED("use ZDICT_finalizeDictionary() instead")
size_t ZDICT_addEntropyTablesFromBuffer(void* dictBuffer, size_t dictContentSize, size_t dictBufferCapacity,
const void* samplesBuffer, const size_t* samplesSizes, unsigned nbSamples);
#endif /* ZDICT_STATIC_LINKING_ONLY */