ext/zstdruby/libzstd/zstd.h in zstd-ruby-1.4.0.0 vs ext/zstdruby/libzstd/zstd.h in zstd-ruby-1.4.1.0
- old
+ new
@@ -69,31 +69,31 @@
*******************************************************************************/
/*------ Version ------*/
#define ZSTD_VERSION_MAJOR 1
#define ZSTD_VERSION_MINOR 4
-#define ZSTD_VERSION_RELEASE 0
+#define ZSTD_VERSION_RELEASE 1
#define ZSTD_VERSION_NUMBER (ZSTD_VERSION_MAJOR *100*100 + ZSTD_VERSION_MINOR *100 + ZSTD_VERSION_RELEASE)
ZSTDLIB_API unsigned ZSTD_versionNumber(void); /**< to check runtime library version */
#define ZSTD_LIB_VERSION ZSTD_VERSION_MAJOR.ZSTD_VERSION_MINOR.ZSTD_VERSION_RELEASE
#define ZSTD_QUOTE(str) #str
#define ZSTD_EXPAND_AND_QUOTE(str) ZSTD_QUOTE(str)
#define ZSTD_VERSION_STRING ZSTD_EXPAND_AND_QUOTE(ZSTD_LIB_VERSION)
ZSTDLIB_API const char* ZSTD_versionString(void); /* requires v1.3.0+ */
-/***************************************
-* Default constant
-***************************************/
+/* *************************************
+ * Default constant
+ ***************************************/
#ifndef ZSTD_CLEVEL_DEFAULT
# define ZSTD_CLEVEL_DEFAULT 3
#endif
-/***************************************
-* Constants
-***************************************/
+/* *************************************
+ * Constants
+ ***************************************/
/* All magic numbers are supposed read/written to/from files/memory using little-endian convention */
#define ZSTD_MAGICNUMBER 0xFD2FB528 /* valid since v0.8.0 */
#define ZSTD_MAGIC_DICTIONARY 0xEC30A437 /* valid since v0.7.0 */
#define ZSTD_MAGIC_SKIPPABLE_START 0x184D2A50 /* all 16 values, from 0x184D2A50 to 0x184D2A5F, signal the beginning of a skippable frame */
@@ -181,13 +181,18 @@
/***************************************
* Explicit context
***************************************/
/*= Compression context
* When compressing many times,
- * it is recommended to allocate a context just once, and re-use it for each successive compression operation.
+ * it is recommended to allocate a context just once,
+ * and re-use it for each successive compression operation.
* This will make workload friendlier for system's memory.
- * Use one context per thread for parallel execution in multi-threaded environments. */
+ * Note : re-using context is just a speed / resource optimization.
+ * It doesn't change the compression ratio, which remains identical.
+ * Note 2 : In multi-threaded environments,
+ * use one different context per thread for parallel execution.
+ */
typedef struct ZSTD_CCtx_s ZSTD_CCtx;
ZSTDLIB_API ZSTD_CCtx* ZSTD_createCCtx(void);
ZSTDLIB_API size_t ZSTD_freeCCtx(ZSTD_CCtx* cctx);
/*! ZSTD_compressCCtx() :
@@ -378,19 +383,21 @@
* ZSTD_c_rsyncable
* ZSTD_c_format
* 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.
*/
ZSTD_c_experimentalParam1=500,
ZSTD_c_experimentalParam2=10,
ZSTD_c_experimentalParam3=1000,
ZSTD_c_experimentalParam4=1001,
ZSTD_c_experimentalParam5=1002,
+ ZSTD_c_experimentalParam6=1003,
} ZSTD_cParameter;
typedef struct {
size_t error;
int lowerBound;
@@ -655,38 +662,54 @@
ZSTDLIB_API size_t ZSTD_compressStream2( ZSTD_CCtx* cctx,
ZSTD_outBuffer* output,
ZSTD_inBuffer* input,
ZSTD_EndDirective endOp);
+
+/* These buffer sizes are softly recommended.
+ * They are not required : ZSTD_compressStream*() happily accepts any buffer size, for both input and output.
+ * Respecting the recommended size just makes it a bit easier for ZSTD_compressStream*(),
+ * reducing the amount of memory shuffling and buffering, resulting in minor performance savings.
+ *
+ * However, note that these recommendations are from the perspective of a C caller program.
+ * If the streaming interface is invoked from some other language,
+ * especially managed ones such as Java or Go, through a foreign function interface such as jni or cgo,
+ * a major performance rule is to reduce crossing such interface to an absolute minimum.
+ * It's not rare that performance ends being spent more into the interface, rather than compression itself.
+ * In which cases, prefer using large buffers, as large as practical,
+ * for both input and output, to reduce the nb of roundtrips.
+ */
ZSTDLIB_API size_t ZSTD_CStreamInSize(void); /**< recommended size for input buffer */
-ZSTDLIB_API size_t ZSTD_CStreamOutSize(void); /**< recommended size for output buffer. Guarantee to successfully flush at least one complete compressed block in all circumstances. */
+ZSTDLIB_API size_t ZSTD_CStreamOutSize(void); /**< recommended size for output buffer. Guarantee to successfully flush at least one complete compressed block. */
-/*******************************************************************************
- * This is a legacy streaming API, and can be replaced by ZSTD_CCtx_reset() and
- * ZSTD_compressStream2(). It is redundant, but is still fully supported.
+
+/* *****************************************************************************
+ * This following is a legacy streaming API.
+ * It can be replaced by ZSTD_CCtx_reset() and ZSTD_compressStream2().
+ * It is redundant, but remains fully supported.
* Advanced parameters and dictionary compression can only be used through the
* new API.
******************************************************************************/
-/**
+/*!
* Equivalent to:
*
* ZSTD_CCtx_reset(zcs, ZSTD_reset_session_only);
* ZSTD_CCtx_refCDict(zcs, NULL); // clear the dictionary (if any)
* ZSTD_CCtx_setParameter(zcs, ZSTD_c_compressionLevel, compressionLevel);
*/
ZSTDLIB_API size_t ZSTD_initCStream(ZSTD_CStream* zcs, int compressionLevel);
-/**
+/*!
* Alternative for ZSTD_compressStream2(zcs, output, input, ZSTD_e_continue).
* NOTE: The return value is different. ZSTD_compressStream() returns a hint for
* the next read size (if non-zero and not an error). ZSTD_compressStream2()
- * returns the number of bytes left to flush (if non-zero and not an error).
+ * returns the minimum nb of bytes left to flush (if non-zero and not an error).
*/
ZSTDLIB_API size_t ZSTD_compressStream(ZSTD_CStream* zcs, ZSTD_outBuffer* output, ZSTD_inBuffer* input);
-/** Equivalent to ZSTD_compressStream2(zcs, output, &emptyInput, ZSTD_e_flush). */
+/*! Equivalent to ZSTD_compressStream2(zcs, output, &emptyInput, ZSTD_e_flush). */
ZSTDLIB_API size_t ZSTD_flushStream(ZSTD_CStream* zcs, ZSTD_outBuffer* output);
-/** Equivalent to ZSTD_compressStream2(zcs, output, &emptyInput, ZSTD_e_end). */
+/*! Equivalent to ZSTD_compressStream2(zcs, output, &emptyInput, ZSTD_e_end). */
ZSTDLIB_API size_t ZSTD_endStream(ZSTD_CStream* zcs, ZSTD_outBuffer* output);
/*-***************************************************************************
* Streaming decompression - HowTo
@@ -967,11 +990,11 @@
ZSTDLIB_API size_t ZSTD_sizeof_DDict(const ZSTD_DDict* ddict);
#endif /* ZSTD_H_235446 */
-/****************************************************************************************
+/* **************************************************************************************
* ADVANCED AND EXPERIMENTAL FUNCTIONS
****************************************************************************************
* The definitions in the following section are considered experimental.
* They are provided for advanced scenarios.
* They should never be used with a dynamic library, as prototypes may change in the future.
@@ -1035,10 +1058,14 @@
#define ZSTD_LDM_BUCKETSIZELOG_MIN 1
#define ZSTD_LDM_BUCKETSIZELOG_MAX 8
#define ZSTD_LDM_HASHRATELOG_MIN 0
#define ZSTD_LDM_HASHRATELOG_MAX (ZSTD_WINDOWLOG_MAX - ZSTD_HASHLOG_MIN)
+/* Advanced parameter bounds */
+#define ZSTD_TARGETCBLOCKSIZE_MIN 64
+#define ZSTD_TARGETCBLOCKSIZE_MAX ZSTD_BLOCKSIZE_MAX
+
/* internal */
#define ZSTD_HASHLOG3_MAX 17
/* --- Advanced types --- */
@@ -1160,11 +1187,11 @@
* note 5 : ZSTD_findDecompressedSize handles multiple frames, and so it must traverse the input to
* read each contained frame header. This is fast as most of the data is skipped,
* however it does mean that all frame data must be present and valid. */
ZSTDLIB_API unsigned long long ZSTD_findDecompressedSize(const void* src, size_t srcSize);
-/** ZSTD_decompressBound() :
+/*! ZSTD_decompressBound() :
* `src` should point to the start of a series of ZSTD encoded and/or skippable frames
* `srcSize` must be the _exact_ size of this series
* (i.e. there should be a frame boundary at `src + srcSize`)
* @return : - upper-bound for the decompressed size of all data in all successive frames
* - if an error occured: ZSTD_CONTENTSIZE_ERROR
@@ -1407,10 +1434,15 @@
* The value must be of type ZSTD_literalCompressionMode_e.
* See ZSTD_literalCompressionMode_t enum definition for details.
*/
#define ZSTD_c_literalCompressionMode ZSTD_c_experimentalParam5
+/* Tries to fit compressed block size to be around targetCBlockSize.
+ * No target when targetCBlockSize == 0.
+ * There is no guarantee on compressed block size (default:0) */
+#define ZSTD_c_targetCBlockSize ZSTD_c_experimentalParam6
+
/*! ZSTD_CCtx_getParameter() :
* Get the requested compression parameter value, selected by enum ZSTD_cParameter,
* and store it into int* value.
* @return : 0, or an error code (which can be tested with ZSTD_isError()).
*/
@@ -1841,10 +1873,10 @@
unsigned headerSize;
unsigned dictID;
unsigned checksumFlag;
} ZSTD_frameHeader;
-/** ZSTD_getFrameHeader() :
+/*! ZSTD_getFrameHeader() :
* decode Frame Header, or requires larger `srcSize`.
* @return : 0, `zfhPtr` is correctly filled,
* >0, `srcSize` is too small, value is wanted `srcSize` amount,
* or an error code, which can be tested using ZSTD_isError() */
ZSTDLIB_API size_t ZSTD_getFrameHeader(ZSTD_frameHeader* zfhPtr, const void* src, size_t srcSize); /**< doesn't consume input */