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ZSTD_estimateCDictSize_advanced()

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ZSTD_estimateCDictSize() now uses same arguments as ZSTD_createCDict()
ZSTD_estimateCDictSize_advanced() uses same arguments as ZSTD_createCDict_advanced()
This commit is contained in:
Yann Collet 2017-06-26 16:47:32 -07:00
parent 0c9a915a28
commit 09ae03a570
5 changed files with 20 additions and 8 deletions
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7
doc/zstd_manual.html
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@ -430,9 +430,12 @@ size_t ZSTD_estimateDStreamSize(ZSTD_frameHeader fHeader);
In this case, get total size by adding ZSTD_estimate?DictSize
</p></pre><BR>
<pre><b>size_t ZSTD_estimateCDictSize(ZSTD_compressionParameters cParams, size_t dictSize, unsigned byReference);
<pre><b>size_t ZSTD_estimateCDictSize(size_t dictSize, int compressionLevel);
size_t ZSTD_estimateCDictSize_advanced(size_t dictSize, ZSTD_compressionParameters cParams, unsigned byReference);
size_t ZSTD_estimateDDictSize(size_t dictSize, unsigned byReference);
</b><p> Note : dictionary created "byReference" are smaller
</b><p> ZSTD_estimateCDictSize() will bet that src size is relatively "small", and content is copied, like ZSTD_createCDict().
ZSTD_estimateCStreamSize_advanced() makes it possible to control precisely compression parameters, like ZSTD_createCDict_advanced().
Note : dictionary created "byReference" are smaller
</p></pre><BR>
<a name="Chapter14"></a><h2>Advanced compression functions</h2><pre></pre>

10
lib/compress/zstd_compress.c
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@ -3361,9 +3361,9 @@ size_t ZSTD_compress(void* dst, size_t dstCapacity, const void* src, size_t srcS
/* ===== Dictionary API ===== */
/*! ZSTD_estimateCDictSize() :
/*! ZSTD_estimateCDictSize_advanced() :
* Estimate amount of memory that will be needed to create a dictionary with following arguments */
size_t ZSTD_estimateCDictSize(ZSTD_compressionParameters cParams, size_t dictSize, unsigned byReference)
size_t ZSTD_estimateCDictSize_advanced(size_t dictSize, ZSTD_compressionParameters cParams, unsigned byReference)
{
DEBUGLOG(5, "sizeof(ZSTD_CDict) : %u", (U32)sizeof(ZSTD_CDict));
DEBUGLOG(5, "CCtx estimate : %u", (U32)ZSTD_estimateCCtxSize_advanced(cParams));
@ -3371,6 +3371,12 @@ size_t ZSTD_estimateCDictSize(ZSTD_compressionParameters cParams, size_t dictSiz
+ (byReference ? 0 : dictSize);
}
size_t ZSTD_estimateCDictSize(size_t dictSize, int compressionLevel)
{
ZSTD_compressionParameters const cParams = ZSTD_getCParams(compressionLevel, 0, dictSize);
return ZSTD_estimateCDictSize_advanced(dictSize, cParams, 0);
}
size_t ZSTD_sizeof_CDict(const ZSTD_CDict* cdict)
{
if (cdict==NULL) return 0; /* support sizeof on NULL */

5
lib/zstd.h
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@ -517,8 +517,11 @@ ZSTDLIB_API size_t ZSTD_estimateCStreamSize_advanced(ZSTD_compressionParameters
ZSTDLIB_API size_t ZSTD_estimateDStreamSize(ZSTD_frameHeader fHeader);
/*! ZSTD_estimate?DictSize() :
* ZSTD_estimateCDictSize() will bet that src size is relatively "small", and content is copied, like ZSTD_createCDict().
* ZSTD_estimateCStreamSize_advanced() makes it possible to control precisely compression parameters, like ZSTD_createCDict_advanced().
* Note : dictionary created "byReference" are smaller */
ZSTDLIB_API size_t ZSTD_estimateCDictSize(ZSTD_compressionParameters cParams, size_t dictSize, unsigned byReference);
ZSTDLIB_API size_t ZSTD_estimateCDictSize(size_t dictSize, int compressionLevel);
ZSTDLIB_API size_t ZSTD_estimateCDictSize_advanced(size_t dictSize, ZSTD_compressionParameters cParams, unsigned byReference);
ZSTDLIB_API size_t ZSTD_estimateDDictSize(size_t dictSize, unsigned byReference);

4
tests/fuzzer.c
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@ -501,7 +501,7 @@ static int basicUnitTests(U32 seed, double compressibility)
DISPLAYLEVEL(4, "test%3i : estimate CDict size : ", testNb++);
{ ZSTD_compressionParameters const cParams = ZSTD_getCParams(1, CNBuffSize, dictSize);
size_t const estimatedSize = ZSTD_estimateCDictSize(cParams, dictSize, 1 /*byReference*/);
size_t const estimatedSize = ZSTD_estimateCDictSize_advanced(dictSize, cParams, 1 /*byReference*/);
DISPLAYLEVEL(4, "OK : %u \n", (U32)estimatedSize);
}
@ -534,7 +534,7 @@ static int basicUnitTests(U32 seed, double compressibility)
DISPLAYLEVEL(4, "test%3i : compress with static CDict : ", testNb++);
{ ZSTD_compressionParameters const cParams = ZSTD_getCParams(1, CNBuffSize, dictSize);
size_t const cdictSize = ZSTD_estimateCDictSize(cParams, dictSize, 0);
size_t const cdictSize = ZSTD_estimateCDictSize_advanced(dictSize, cParams, 0);
void* const cdictBuffer = malloc(cdictSize);
if (cdictBuffer==NULL) goto _output_error;
{ ZSTD_CDict* const cdict = ZSTD_initStaticCDict(cdictBuffer, cdictSize,

2
tests/zstreamtest.c
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@ -212,7 +212,7 @@ static int basicUnitTests(U32 seed, double compressibility, ZSTD_customMem custo
{ ZSTD_compressionParameters const cParams = ZSTD_getCParams(1, CNBufferSize, dictSize);
size_t const s = ZSTD_estimateCStreamSize_advanced(cParams)
/* uses ZSTD_initCStream_usingDict() */
+ ZSTD_estimateCDictSize(cParams, dictSize, 0);
+ ZSTD_estimateCDictSize_advanced(dictSize, cParams, 0);
if (ZSTD_isError(s)) goto _output_error;
DISPLAYLEVEL(3, "OK (%u bytes) \n", (U32)s);
}