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pushed experimental parameters 

into ZSTD_STATIC_LINKING_ONLY section
dev
Yann Collet 2018-11-21 16:18:55 -08:00
parent d4d4e109e9
commit d3a0c71259
2 changed files with 65 additions and 84 deletions
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56
doc/zstd_manual.html
View File

@ -503,48 +503,20 @@ size_t ZSTD_sizeof_DDict(const ZSTD_DDict* ddict);
* 9: full window; 8: w/2; 7: w/4; 6: w/8; 5:w/16; 4: w/32; 3:w/64; 2:w/128; 1:w/256;
* default value is 6 : use 1/8th of windowSize */
</b>/* =================================================================== */<b>
</b>/* experimental parameters - no stability guaranteed */<b>
</b>/* => note : should this part be exported in a different section of zstd.h ? */<b>
</b>/* =================================================================== */<b>
</b>/* compression format */<b>
ZSTD_p_format = 10, </b>/* See ZSTD_format_e enum definition.<b>
* Cast selected format as unsigned for ZSTD_CCtx_setParameter() compatibility. */
ZSTD_p_forceMaxWindow=1100, </b>/* Force back-reference distances to remain < windowSize,<b>
* even when referencing into Dictionary content (default:0) */
ZSTD_p_forceAttachDict, </b>/* Controls whether the contents of a CDict are<b>
* used in place, or whether they are copied into
* the working context.
*
* Accepts values from the ZSTD_dictAttachPref_e
* enum. See the comments on that enum for an
* explanation of the feature.
*/
</b>/* Question : should rsyncable remain experimental, or be part of candidate for stable ? */<b>
ZSTD_p_rsyncable, </b>/* Enables rsyncable mode, which makes compressed<b>
* files more rsync friendly by adding periodic
* synchronization points to the compressed data.
* The target average block size is
* ZSTD_p_jobSize / 2. You can modify the job size
* to increase or decrease the granularity of the
* synchronization point. Once the jobSize is
* smaller than the window size, you will start to
* see degraded compression ratio.
* NOTE: This only works when multithreading is
* enabled.
* NOTE: You probably don't want to use this with
* long range mode, since that will decrease the
* effectiveness of the synchronization points,
* but your milage may vary.
* NOTE: Rsyncable mode will limit the maximum
* compression speed to approximately 400 MB/s.
* If your compression level is already running
* significantly slower than that (< 200 MB/s),
* the speed won't be significantly impacted.
*/
</b>/* note : additional experimental parameters are also available<b>
* within the experimental section of the API.
* At the time of this writing, they include :
* ZSTD_p_rsyncable
* ZSTD_p_format
* ZSTD_p_forceMaxWindow
* ZSTD_p_forceAttachDict
* Because they are not stable, it's necessary to define ZSTD_STATIC_LINKING_ONLY to access them.
* note : never use experimentalParam names directly
*/
ZSTD_p_experimentalParam1=500,
ZSTD_p_experimentalParam2=10,
ZSTD_p_experimentalParam3=1000,
ZSTD_p_experimentalParam4
} ZSTD_cParameter;
</b></pre><BR>
<pre><b>typedef struct {

93
lib/zstd.h
View File

@ -600,48 +600,20 @@ typedef enum {
* 9: full window; 8: w/2; 7: w/4; 6: w/8; 5:w/16; 4: w/32; 3:w/64; 2:w/128; 1:w/256;
* default value is 6 : use 1/8th of windowSize */
/* =================================================================== */
/* experimental parameters - no stability guaranteed */
/* => note : should this part be exported in a different section of zstd.h ? */
/* =================================================================== */
/* compression format */
ZSTD_p_format = 10, /* See ZSTD_format_e enum definition.
* Cast selected format as unsigned for ZSTD_CCtx_setParameter() compatibility. */
ZSTD_p_forceMaxWindow=1100, /* Force back-reference distances to remain < windowSize,
* even when referencing into Dictionary content (default:0) */
ZSTD_p_forceAttachDict, /* Controls whether the contents of a CDict are
* used in place, or whether they are copied into
* the working context.
*
* Accepts values from the ZSTD_dictAttachPref_e
* enum. See the comments on that enum for an
* explanation of the feature.
*/
/* Question : should rsyncable remain experimental, or be part of candidate for stable ? */
ZSTD_p_rsyncable, /* Enables rsyncable mode, which makes compressed
* files more rsync friendly by adding periodic
* synchronization points to the compressed data.
* The target average block size is
* ZSTD_p_jobSize / 2. You can modify the job size
* to increase or decrease the granularity of the
* synchronization point. Once the jobSize is
* smaller than the window size, you will start to
* see degraded compression ratio.
* NOTE: This only works when multithreading is
* enabled.
* NOTE: You probably don't want to use this with
* long range mode, since that will decrease the
* effectiveness of the synchronization points,
* but your milage may vary.
* NOTE: Rsyncable mode will limit the maximum
* compression speed to approximately 400 MB/s.
* If your compression level is already running
* significantly slower than that (< 200 MB/s),
* the speed won't be significantly impacted.
*/
/* note : additional experimental parameters are also available
* within the experimental section of the API.
* At the time of this writing, they include :
* ZSTD_p_rsyncable
* ZSTD_p_format
* ZSTD_p_forceMaxWindow
* ZSTD_p_forceAttachDict
* Because they are not stable, it's necessary to define ZSTD_STATIC_LINKING_ONLY to access them.
* note : never use experimentalParam names directly
*/
ZSTD_p_experimentalParam1=500,
ZSTD_p_experimentalParam2=10,
ZSTD_p_experimentalParam3=1000,
ZSTD_p_experimentalParam4
} ZSTD_cParameter;
@ -1238,6 +1210,43 @@ ZSTDLIB_API size_t ZSTD_CCtx_loadDictionary_advanced(ZSTD_CCtx* cctx, const void
* how to interpret prefix content (automatic ? force raw mode (default) ? full mode only ?) */
ZSTDLIB_API size_t ZSTD_CCtx_refPrefix_advanced(ZSTD_CCtx* cctx, const void* prefix, size_t prefixSize, ZSTD_dictContentType_e dictContentType);
/* === experimental parameters === */
/* these parameters can be used with ZSTD_setParameter()
* they are not guaranteed to remain supported in the future */
/* Enables rsyncable mode,
* which makes compressed files more rsync friendly
* by adding periodic synchronization points to the compressed data.
* The target average block size is ZSTD_p_jobSize / 2.
* It's possible to modify the job size to increase or decrease
* the granularity of the synchronization point.
* Once the jobSize is smaller than the window size,
* it will result in compression ratio degradation.
* NOTE 1: rsyncable mode only works when multithreading is enabled.
* NOTE 2: rsyncable performs poorly in combination with long range mode,
* since it will decrease the effectiveness of synchronization points,
* though mileage may vary.
* NOTE 3: Rsyncable mode limits maximum compression speed to ~400 MB/s.
* If the selected compression level is already running significantly slower,
* the overall speed won't be significantly impacted.
*/
#define ZSTD_p_rsyncable ZSTD_p_experimentalParam1
/* Select a compression format.
* The value must be of type ZSTD_format_e.
* See ZSTD_format_e enum definition for details */
#define ZSTD_p_format ZSTD_p_experimentalParam2
/* Force back-reference distances to remain < windowSize,
* even when referencing into Dictionary content (default:0) */
#define ZSTD_p_forceMaxWindow ZSTD_p_experimentalParam3
/* Controls whether the contents of a CDict
* are used in place, or copied into the working context.
* Accepts values from the ZSTD_dictAttachPref_e enum.
* See the comments on that enum for an explanation of the feature. */
#define ZSTD_p_forceAttachDict ZSTD_p_experimentalParam4
/*! ZSTD_CCtx_getParameter() :
* Get the requested value of one compression parameter, selected by enum ZSTD_cParameter.
* @result : 0, or an error code (which can be tested with ZSTD_isError()).