diff --git a/doc/zstd_manual.html b/doc/zstd_manual.html
index 024c10e63..c38c1f60c 100644
--- a/doc/zstd_manual.html
+++ b/doc/zstd_manual.html
@@ -318,6 +318,7 @@ size_t ZSTD_freeDCtx(ZSTD_DCtx* dctx);
* ZSTD_c_forceMaxWindow
* ZSTD_c_forceAttachDict
* ZSTD_c_literalCompressionMode
+ * ZSTD_c_targetCBlockSize
* Because they are not stable, it's necessary to define ZSTD_STATIC_LINKING_ONLY to access them.
* note : never ever use experimentalParam? names directly;
* also, the enums values themselves are unstable and can still change.
@@ -327,6 +328,7 @@ size_t ZSTD_freeDCtx(ZSTD_DCtx* dctx);
ZSTD_c_experimentalParam3=1000,
ZSTD_c_experimentalParam4=1001,
ZSTD_c_experimentalParam5=1002,
+ ZSTD_c_experimentalParam6=1003,
} ZSTD_cParameter;
typedef struct {
diff --git a/lib/compress/zstd_compress.c b/lib/compress/zstd_compress.c
index b4feaef83..bf173db5d 100644
--- a/lib/compress/zstd_compress.c
+++ b/lib/compress/zstd_compress.c
@@ -385,6 +385,11 @@ ZSTD_bounds ZSTD_cParam_getBounds(ZSTD_cParameter param)
bounds.upperBound = ZSTD_lcm_uncompressed;
return bounds;
+ case ZSTD_c_targetCBlockSize:
+ bounds.lowerBound = ZSTD_TARGETCBLOCKSIZE_MIN;
+ bounds.upperBound = ZSTD_TARGETCBLOCKSIZE_MAX;
+ return bounds;
+
default:
{ ZSTD_bounds const boundError = { ERROR(parameter_unsupported), 0, 0 };
return boundError;
@@ -452,6 +457,7 @@ static int ZSTD_isUpdateAuthorized(ZSTD_cParameter param)
case ZSTD_c_ldmHashRateLog:
case ZSTD_c_forceAttachDict:
case ZSTD_c_literalCompressionMode:
+ case ZSTD_c_targetCBlockSize:
default:
return 0;
}
@@ -497,6 +503,7 @@ size_t ZSTD_CCtx_setParameter(ZSTD_CCtx* cctx, ZSTD_cParameter param, int value)
case ZSTD_c_ldmHashLog:
case ZSTD_c_ldmMinMatch:
case ZSTD_c_ldmBucketSizeLog:
+ case ZSTD_c_targetCBlockSize:
break;
default: RETURN_ERROR(parameter_unsupported);
@@ -671,6 +678,12 @@ size_t ZSTD_CCtxParams_setParameter(ZSTD_CCtx_params* CCtxParams,
CCtxParams->ldmParams.hashRateLog = value;
return CCtxParams->ldmParams.hashRateLog;
+ case ZSTD_c_targetCBlockSize :
+ if (value!=0) /* 0 ==> default */
+ BOUNDCHECK(ZSTD_c_targetCBlockSize, value);
+ CCtxParams->targetCBlockSize = value;
+ return CCtxParams->targetCBlockSize;
+
default: RETURN_ERROR(parameter_unsupported, "unknown parameter");
}
}
@@ -773,6 +786,9 @@ size_t ZSTD_CCtxParams_getParameter(
case ZSTD_c_ldmHashRateLog :
*value = CCtxParams->ldmParams.hashRateLog;
break;
+ case ZSTD_c_targetCBlockSize :
+ *value = (int)CCtxParams->targetCBlockSize;
+ break;
default: RETURN_ERROR(parameter_unsupported, "unknown parameter");
}
return 0;
diff --git a/lib/compress/zstd_compress_internal.h b/lib/compress/zstd_compress_internal.h
index ee9d9e31a..8a9001c41 100644
--- a/lib/compress/zstd_compress_internal.h
+++ b/lib/compress/zstd_compress_internal.h
@@ -194,6 +194,9 @@ struct ZSTD_CCtx_params_s {
int compressionLevel;
int forceWindow; /* force back-references to respect limit of
* 1<ldmMinMatch = 0;
ret->ldmBucketSizeLog = FIO_LDM_PARAM_NOTSET;
ret->ldmHashRateLog = FIO_LDM_PARAM_NOTSET;
+ ret->targetCBlockSize = 0;
ret->literalCompressionMode = ZSTD_lcm_auto;
return ret;
}
@@ -416,6 +418,10 @@ void FIO_setRsyncable(FIO_prefs_t* const prefs, int rsyncable) {
prefs->rsyncable = rsyncable;
}
+void FIO_setTargetCBlockSize(FIO_prefs_t* const prefs, size_t targetCBlockSize) {
+ prefs->targetCBlockSize = targetCBlockSize;
+}
+
void FIO_setLiteralCompressionMode(
FIO_prefs_t* const prefs,
ZSTD_literalCompressionMode_e mode) {
@@ -656,6 +662,8 @@ static cRess_t FIO_createCResources(FIO_prefs_t* const prefs,
CHECK( ZSTD_CCtx_setParameter(ress.cctx, ZSTD_c_checksumFlag, prefs->checksumFlag) );
/* compression level */
CHECK( ZSTD_CCtx_setParameter(ress.cctx, ZSTD_c_compressionLevel, cLevel) );
+ /* max compressed block size */
+ CHECK( ZSTD_CCtx_setParameter(ress.cctx, ZSTD_c_targetCBlockSize, (int)prefs->targetCBlockSize) );
/* long distance matching */
CHECK( ZSTD_CCtx_setParameter(ress.cctx, ZSTD_c_enableLongDistanceMatching, prefs->ldmFlag) );
CHECK( ZSTD_CCtx_setParameter(ress.cctx, ZSTD_c_ldmHashLog, prefs->ldmHashLog) );
diff --git a/programs/fileio.h b/programs/fileio.h
index e46633752..311f8c0e1 100644
--- a/programs/fileio.h
+++ b/programs/fileio.h
@@ -71,6 +71,7 @@ void FIO_setOverlapLog(FIO_prefs_t* const prefs, int overlapLog);
void FIO_setRemoveSrcFile(FIO_prefs_t* const prefs, unsigned flag);
void FIO_setSparseWrite(FIO_prefs_t* const prefs, unsigned sparse); /**< 0: no sparse; 1: disable on stdout; 2: always enabled */
void FIO_setRsyncable(FIO_prefs_t* const prefs, int rsyncable);
+void FIO_setTargetCBlockSize(FIO_prefs_t* const prefs, size_t targetCBlockSize);
void FIO_setLiteralCompressionMode(
FIO_prefs_t* const prefs,
ZSTD_literalCompressionMode_e mode);
diff --git a/programs/zstdcli.c b/programs/zstdcli.c
index c0dd925ce..1d2e1ec73 100644
--- a/programs/zstdcli.c
+++ b/programs/zstdcli.c
@@ -141,6 +141,7 @@ static int usage_advanced(const char* programName)
DISPLAY( "--long[=#]: enable long distance matching with given window log (default: %u)\n", g_defaultMaxWindowLog);
DISPLAY( "--fast[=#]: switch to ultra fast compression level (default: %u)\n", 1);
DISPLAY( "--adapt : dynamically adapt compression level to I/O conditions \n");
+ DISPLAY( "--target-compressed-block-size=# : make compressed block near targeted size \n");
#ifdef ZSTD_MULTITHREAD
DISPLAY( " -T# : spawns # compression threads (default: 1, 0==# cores) \n");
DISPLAY( " -B# : select size of each job (default: 0==automatic) \n");
@@ -555,6 +556,7 @@ int main(int argCount, const char* argv[])
const char* suffix = ZSTD_EXTENSION;
unsigned maxDictSize = g_defaultMaxDictSize;
unsigned dictID = 0;
+ size_t targetCBlockSize = 0;
int dictCLevel = g_defaultDictCLevel;
unsigned dictSelect = g_defaultSelectivityLevel;
#ifdef UTIL_HAS_CREATEFILELIST
@@ -711,6 +713,7 @@ int main(int argCount, const char* argv[])
if (longCommandWArg(&argument, "--maxdict=")) { maxDictSize = readU32FromChar(&argument); continue; }
if (longCommandWArg(&argument, "--dictID=")) { dictID = readU32FromChar(&argument); continue; }
if (longCommandWArg(&argument, "--zstd=")) { if (!parseCompressionParameters(argument, &compressionParams)) CLEAN_RETURN(badusage(programName)); continue; }
+ if (longCommandWArg(&argument, "--target-compressed-block-size=")) { targetCBlockSize = readU32FromChar(&argument); continue; }
if (longCommandWArg(&argument, "--long")) {
unsigned ldmWindowLog = 0;
ldmFlag = 1;
@@ -1115,6 +1118,7 @@ int main(int argCount, const char* argv[])
FIO_setAdaptMin(prefs, adaptMin);
FIO_setAdaptMax(prefs, adaptMax);
FIO_setRsyncable(prefs, rsyncable);
+ FIO_setTargetCBlockSize(prefs, targetCBlockSize);
FIO_setLiteralCompressionMode(prefs, literalCompressionMode);
if (adaptMin > cLevel) cLevel = adaptMin;
if (adaptMax < cLevel) cLevel = adaptMax;
@@ -1124,7 +1128,7 @@ int main(int argCount, const char* argv[])
else
operationResult = FIO_compressMultipleFilenames(prefs, filenameTable, filenameIdx, outFileName, suffix, dictFileName, cLevel, compressionParams);
#else
- (void)suffix; (void)adapt; (void)rsyncable; (void)ultra; (void)cLevel; (void)ldmFlag; (void)literalCompressionMode; /* not used when ZSTD_NOCOMPRESS set */
+ (void)suffix; (void)adapt; (void)rsyncable; (void)ultra; (void)cLevel; (void)ldmFlag; (void)literalCompressionMode; (void)targetCBlockSize; /* not used when ZSTD_NOCOMPRESS set */
DISPLAY("Compression not supported \n");
#endif
} else { /* decompression or test */