ddidderr/zstd-rs
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

changed searchLength into minMatch

Browse Source 
refactored all relevant API and calls
for consistency.
This commit is contained in:
Yann Collet
2018-11-20 14:56:07 -08:00
parent 114bd4346e
commit e874dacc08
18 changed files with 197 additions and 134 deletions
Download Patch File Download Diff File Expand all files Collapse all files
lib/zstd.h
+22 -18
View File
@@ -513,9 +513,11 @@ typedef enum {
* More attempts result in better and slower compression.
* This parameter is useless when using "fast" and "dFast" strategies.
* Special: value 0 means "use default searchLog". */
ZSTD_p_minMatch=105, /* Minimum size of searched matches (note : repCode matches can be smaller).
* Larger values make faster compression and decompression, but decrease ratio.
* Must be clamped between ZSTD_SEARCHLENGTH_MIN and ZSTD_SEARCHLENGTH_MAX.
ZSTD_p_minMatch=105, /* Minimum size of searched matches.
* Note that Zstandard can still find matches of smaller size,
* it just tweaks its search algorithm to look for this size and larger.
* Larger values increase compression and decompression speed, but decrease ratio.
* Must be clamped between ZSTD_MINMATCH_MIN and ZSTD_MINMATCH_MAX.
* Note that currently, for all strategies < btopt, effective minimum is 4.
* , for all strategies > fast, effective maximum is 6.
* Special: value 0 means "use default minMatchLength". */
@@ -528,7 +530,6 @@ typedef enum {
* Larger values make compression faster, and weaker.
* Special: value 0 means "use default targetLength". */
ZSTD_p_compressionStrategy=107, /* See ZSTD_strategy enum definition.
* Cast selected strategy as unsigned for ZSTD_CCtx_setParameter() compatibility.
* The higher the value of selected strategy, the more complex it is,
* resulting in stronger and slower compression.
* Special: value 0 means "use default strategy". */
@@ -631,16 +632,20 @@ typedef enum {
} ZSTD_cParameter;
/*! ZSTD_cParam_lowerBound() and ZSTD_cParam_upperBound() :
* All parameters must respect lower/upper bounds,
* otherwise they will either trigger an error
* or be automatically clamped.
* @return : requested bound (inclusive)
* note : if the request specifies a non-existing parameter, it will return 0.
*/
ZSTDLIB_API int ZSTD_cParam_lowerBound(ZSTD_cParameter cParam);
ZSTDLIB_API int ZSTD_cParam_upperBound(ZSTD_cParameter cParam);
typedef struct {
size_t error;
int lowerBound;
int upperBound;
} ZSTD_bounds;
/*! ZSTD_cParam_getBounds() :
* All parameters must belong to an interval with lower and upper bounds,
* otherwise they will either trigger an error or be automatically clamped.
* @return : a structure, ZSTD_bounds, which contains
* - an error status field, which must be tested using ZSTD_isError()
* - both lower and upper bounds, inclusive
*/
ZSTDLIB_API ZSTD_bounds ZSTD_cParam_getBounds(ZSTD_cParameter cParam);
/*! ZSTD_CCtx_setParameter() :
* Set one compression parameter, selected by enum ZSTD_cParameter.
@@ -651,8 +656,7 @@ ZSTDLIB_API int ZSTD_cParam_upperBound(ZSTD_cParameter cParam);
* the following parameters can be updated _during_ compression (within same frame):
* => compressionLevel, hashLog, chainLog, searchLog, minMatch, targetLength and strategy.
* new parameters will be active for next job only (after a flush()).
* @result : informational value (typically, value being effectively set, after clamping),
* or an error code (which can be tested with ZSTD_isError()). */
* @return : an error code (which can be tested using ZSTD_isError()). */
ZSTDLIB_API size_t ZSTD_CCtx_setParameter(ZSTD_CCtx* cctx, ZSTD_cParameter param, int value);
/*! ZSTD_CCtx_setPledgedSrcSize() :
@@ -903,8 +907,8 @@ ZSTDLIB_API size_t ZSTD_decompress_generic(ZSTD_DCtx* dctx,
#define ZSTD_CHAINLOG_MIN ZSTD_HASHLOG_MIN
#define ZSTD_SEARCHLOG_MAX (ZSTD_WINDOWLOG_MAX-1)
#define ZSTD_SEARCHLOG_MIN 1
#define ZSTD_SEARCHLENGTH_MAX 7 /* only for ZSTD_fast, other strategies are limited to 6 */
#define ZSTD_SEARCHLENGTH_MIN 3 /* only for ZSTD_btopt, other strategies are limited to 4 */
#define ZSTD_MINMATCH_MAX 7 /* only for ZSTD_fast, other strategies are limited to 6 */
#define ZSTD_MINMATCH_MIN 3 /* only for ZSTD_btopt+, faster strategies are limited to 4 */
#define ZSTD_TARGETLENGTH_MAX ZSTD_BLOCKSIZE_MAX
#define ZSTD_TARGETLENGTH_MIN 0 /* note : comparing this constant to an unsigned results in a tautological test */
@@ -923,7 +927,7 @@ typedef struct {
unsigned chainLog; /**< fully searched segment : larger == more compression, slower, more memory (useless for fast) */
unsigned hashLog; /**< dispatch table : larger == faster, more memory */
unsigned searchLog; /**< nb of searches : larger == more compression, slower */
unsigned searchLength; /**< match length searched : larger == faster decompression, sometimes less compression */
unsigned minMatch; /**< match length searched : larger == faster decompression, sometimes less compression */
unsigned targetLength; /**< acceptable match size for optimal parser (only) : larger == more compression, slower */
ZSTD_strategy strategy; /**< see ZSTD_strategy definition above */
} ZSTD_compressionParameters;