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MINMATCH=3 or 4 selected in ZSTD frame

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This commit is contained in:
inikep 2016-02-22 15:53:42 +01:00
parent 84f43e2359
commit 6b3739c8e5
2 changed files with 16 additions and 11 deletions
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17
lib/zstd_compress.c
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@ -2144,7 +2144,7 @@ size_t ZSTD_compressBegin_advanced(ZSTD_CCtx* zc,
if (ZSTD_isError(errorCode)) return errorCode; if (ZSTD_isError(errorCode)) return errorCode;
MEM_writeLE32(zc->headerBuffer, ZSTD_MAGICNUMBER); /* Write Header */ MEM_writeLE32(zc->headerBuffer, ZSTD_MAGICNUMBER); /* Write Header */
((BYTE*)zc->headerBuffer)[4] = (BYTE)(params.windowLog - ZSTD_WINDOWLOG_ABSOLUTEMIN); ((BYTE*)zc->headerBuffer)[4] = (BYTE)(params.windowLog - ZSTD_WINDOWLOG_ABSOLUTEMIN + ((params.searchLength==3)<<4));
zc->hbSize = ZSTD_frameHeaderSize_min; zc->hbSize = ZSTD_frameHeaderSize_min;
zc->stage = 0; zc->stage = 0;
@ -2259,7 +2259,7 @@ size_t ZSTD_compress(void* dst, size_t maxDstSize, const void* src, size_t srcSi
/*-===== Pre-defined compression levels =====-*/ /*-===== Pre-defined compression levels =====-*/
#define ZSTD_MAX_CLEVEL 22 #define ZSTD_MAX_CLEVEL 25
unsigned ZSTD_maxCLevel(void) { return ZSTD_MAX_CLEVEL; } unsigned ZSTD_maxCLevel(void) { return ZSTD_MAX_CLEVEL; }
@ -2284,11 +2284,14 @@ static const ZSTD_parameters ZSTD_defaultParameters[4][ZSTD_MAX_CLEVEL+1] = {
{ 0, 23, 23, 23, 0, 5, 5, 4, ZSTD_lazy2 }, /* level 15 */ { 0, 23, 23, 23, 0, 5, 5, 4, ZSTD_lazy2 }, /* level 15 */
{ 0, 23, 22, 22, 0, 5, 5, 4, ZSTD_btlazy2 }, /* level 16 */ { 0, 23, 22, 22, 0, 5, 5, 4, ZSTD_btlazy2 }, /* level 16 */
{ 0, 24, 24, 23, 0, 4, 5, 4, ZSTD_btlazy2 }, /* level 17 */ { 0, 24, 24, 23, 0, 4, 5, 4, ZSTD_btlazy2 }, /* level 17 */
{ 0, 24, 24, 23, 16, 5, 5, 30, ZSTD_btopt }, /* level 18 */ { 0, 24, 24, 23, 0, 5, 5, 30, ZSTD_btopt }, /* level 18 */
{ 0, 25, 25, 24, 16, 5, 4, 40, ZSTD_btopt }, /* level 19 */ { 0, 25, 25, 24, 0, 5, 4, 40, ZSTD_btopt }, /* level 19 */
{ 0, 26, 26, 25, 16, 8, 4,256, ZSTD_btopt }, /* level 20 */ { 0, 26, 26, 25, 0, 8, 4,256, ZSTD_btopt }, /* level 20 */
{ 0, 26, 27, 25, 24, 10, 4,256, ZSTD_btopt }, /* level 21 */ { 0, 26, 27, 25, 0, 10, 4,256, ZSTD_btopt }, /* level 21 */
{ 0, 26, 26, 25, 16, 8, 3,256, ZSTD_btopt }, /* level 20+MM3 */ { 0, 24, 24, 23, 16, 5, 3, 30, ZSTD_btopt }, /* level 22 */
{ 0, 25, 25, 24, 16, 5, 3, 40, ZSTD_btopt }, /* level 23 */
{ 0, 26, 26, 25, 16, 8, 3,256, ZSTD_btopt }, /* level 24 */
{ 0, 26, 27, 25, 24, 10, 3,256, ZSTD_btopt }, /* level 25 */
}, },
{ /* for srcSize <= 256 KB */ { /* for srcSize <= 256 KB */
/* l, W, C, H, H3, S, L, T, strat */ /* l, W, C, H, H3, S, L, T, strat */

10
lib/zstd_decompress.c
View File

@ -292,7 +292,8 @@ size_t ZSTD_getFrameParams(ZSTD_parameters* params, const void* src, size_t srcS
if (magicNumber != ZSTD_MAGICNUMBER) return ERROR(prefix_unknown); if (magicNumber != ZSTD_MAGICNUMBER) return ERROR(prefix_unknown);
memset(params, 0, sizeof(*params)); memset(params, 0, sizeof(*params));
params->windowLog = (((const BYTE*)src)[4] & 15) + ZSTD_WINDOWLOG_ABSOLUTEMIN; params->windowLog = (((const BYTE*)src)[4] & 15) + ZSTD_WINDOWLOG_ABSOLUTEMIN;
if ((((const BYTE*)src)[4] >> 4) != 0) return ERROR(frameParameter_unsupported); /* reserved bits */ params->searchLength = (((const BYTE*)src)[4] & 16) ? MINMATCH-1 : MINMATCH;
if ((((const BYTE*)src)[4] >> 5) != 0) return ERROR(frameParameter_unsupported); /* reserved 3 bits */
return 0; return 0;
} }
@ -614,7 +615,7 @@ typedef struct {
static void ZSTD_decodeSequence(seq_t* seq, seqState_t* seqState) static void ZSTD_decodeSequence(seq_t* seq, seqState_t* seqState, const U32 mls)
{ {
size_t litLength; size_t litLength;
size_t prevOffset; size_t prevOffset;
@ -669,7 +670,7 @@ static void ZSTD_decodeSequence(seq_t* seq, seqState_t* seqState)
} }
if (dumps >= de) dumps = de-1; /* late correction, to avoid read overflow (data is now corrupted anyway) */ if (dumps >= de) dumps = de-1; /* late correction, to avoid read overflow (data is now corrupted anyway) */
} }
matchLength += MINMATCH; matchLength += mls;
/* save result */ /* save result */
seq->litLength = litLength; seq->litLength = litLength;
@ -784,6 +785,7 @@ static size_t ZSTD_decompressSequences(
const BYTE* const base = (const BYTE*) (dctx->base); const BYTE* const base = (const BYTE*) (dctx->base);
const BYTE* const vBase = (const BYTE*) (dctx->vBase); const BYTE* const vBase = (const BYTE*) (dctx->vBase);
const BYTE* const dictEnd = (const BYTE*) (dctx->dictEnd); const BYTE* const dictEnd = (const BYTE*) (dctx->dictEnd);
const U32 mls = dctx->params.searchLength;
/* Build Decoding Tables */ /* Build Decoding Tables */
errorCode = ZSTD_decodeSeqHeaders(&nbSeq, &dumps, &dumpsLength, errorCode = ZSTD_decodeSeqHeaders(&nbSeq, &dumps, &dumpsLength,
@ -811,7 +813,7 @@ static size_t ZSTD_decompressSequences(
for ( ; (BIT_reloadDStream(&(seqState.DStream)) <= BIT_DStream_completed) && nbSeq ; ) { for ( ; (BIT_reloadDStream(&(seqState.DStream)) <= BIT_DStream_completed) && nbSeq ; ) {
size_t oneSeqSize; size_t oneSeqSize;
nbSeq--; nbSeq--;
ZSTD_decodeSequence(&sequence, &seqState); ZSTD_decodeSequence(&sequence, &seqState, mls);
oneSeqSize = ZSTD_execSequence(op, oend, sequence, &litPtr, litLimit_8, base, vBase, dictEnd); oneSeqSize = ZSTD_execSequence(op, oend, sequence, &litPtr, litLimit_8, base, vBase, dictEnd);
if (ZSTD_isError(oneSeqSize)) return oneSeqSize; if (ZSTD_isError(oneSeqSize)) return oneSeqSize;
op += oneSeqSize; op += oneSeqSize;