const void* src, size_t srcSize);
-/**************************
-* Simple dictionary API
-***************************/
-/*! ZSTD_compress_usingDict() :
- * Compression at an explicit compression level using a Dictionary.
- * A dictionary can be any arbitrary data segment (also called a prefix),
- * or a buffer with specified information (see dictBuilder/zdict.h).
- * Note : This function loads the dictionary, resulting in significant startup delay.
- * It's intended for a dictionary used only once.
- * Note 2 : When `dict == NULL || dictSize < 8` no dictionary is used. */
-ZSTDLIB_API size_t ZSTD_compress_usingDict(ZSTD_CCtx* ctx,
- void* dst, size_t dstCapacity,
- const void* src, size_t srcSize,
- const void* dict,size_t dictSize,
- int compressionLevel);
-
-/*! ZSTD_decompress_usingDict() :
- * Decompression using a known Dictionary.
- * Dictionary must be identical to the one used during compression.
- * Note : This function loads the dictionary, resulting in significant startup delay.
- * It's intended for a dictionary used only once.
- * Note : When `dict == NULL || dictSize < 8` no dictionary is used. */
-ZSTDLIB_API size_t ZSTD_decompress_usingDict(ZSTD_DCtx* dctx,
- void* dst, size_t dstCapacity,
- const void* src, size_t srcSize,
- const void* dict,size_t dictSize);
-
-
-/***********************************
- * Bulk processing dictionary API
- **********************************/
-typedef struct ZSTD_CDict_s ZSTD_CDict;
-
-/*! ZSTD_createCDict() :
- * When compressing multiple messages / blocks using the same dictionary, it's recommended to load it only once.
- * ZSTD_createCDict() will create a digested dictionary, ready to start future compression operations without startup cost.
- * ZSTD_CDict can be created once and shared by multiple threads concurrently, since its usage is read-only.
- * `dictBuffer` can be released after ZSTD_CDict creation, because its content is copied within CDict.
- * Consider experimental function `ZSTD_createCDict_byReference()` if you prefer to not duplicate `dictBuffer` content.
- * Note : A ZSTD_CDict can be created from an empty dictBuffer, but it is inefficient when used to compress small data. */
-ZSTDLIB_API ZSTD_CDict* ZSTD_createCDict(const void* dictBuffer, size_t dictSize,
- int compressionLevel);
-
-/*! ZSTD_freeCDict() :
- * Function frees memory allocated by ZSTD_createCDict(). */
-ZSTDLIB_API size_t ZSTD_freeCDict(ZSTD_CDict* CDict);
-
-/*! ZSTD_compress_usingCDict() :
- * Compression using a digested Dictionary.
- * Recommended when same dictionary is used multiple times.
- * Note : compression level is _decided at dictionary creation time_,
- * and frame parameters are hardcoded (dictID=yes, contentSize=yes, checksum=no) */
-ZSTDLIB_API size_t ZSTD_compress_usingCDict(ZSTD_CCtx* cctx,
- void* dst, size_t dstCapacity,
- const void* src, size_t srcSize,
- const ZSTD_CDict* cdict);
-
-
-typedef struct ZSTD_DDict_s ZSTD_DDict;
-
-/*! ZSTD_createDDict() :
- * Create a digested dictionary, ready to start decompression operation without startup delay.
- * dictBuffer can be released after DDict creation, as its content is copied inside DDict. */
-ZSTDLIB_API ZSTD_DDict* ZSTD_createDDict(const void* dictBuffer, size_t dictSize);
-
-/*! ZSTD_freeDDict() :
- * Function frees memory allocated with ZSTD_createDDict() */
-ZSTDLIB_API size_t ZSTD_freeDDict(ZSTD_DDict* ddict);
-
-/*! ZSTD_decompress_usingDDict() :
- * Decompression using a digested Dictionary.
- * Recommended when same dictionary is used multiple times. */
-ZSTDLIB_API size_t ZSTD_decompress_usingDDict(ZSTD_DCtx* dctx,
- void* dst, size_t dstCapacity,
- const void* src, size_t srcSize,
- const ZSTD_DDict* ddict);
-
-
/***************************************
* Advanced compression API
***************************************/
*/
ZSTDLIB_API size_t ZSTD_CCtx_setPledgedSrcSize(ZSTD_CCtx* cctx, unsigned long long pledgedSrcSize);
-/*! ZSTD_CCtx_loadDictionary() :
- * Create an internal CDict from `dict` buffer.
- * Decompression will have to use same dictionary.
- * @result : 0, or an error code (which can be tested with ZSTD_isError()).
- * Special: Loading a NULL (or 0-size) dictionary invalidates previous dictionary,
- * meaning "return to no-dictionary mode".
- * Note 1 : Dictionary is sticky, it will be used for all future compressed frames.
- * To return to "no-dictionary" situation, load a NULL dictionary (or reset parameters).
- * Note 2 : Loading a dictionary involves building tables.
- * It's also a CPU consuming operation, with non-negligible impact on latency.
- * Tables are dependent on compression parameters, and for this reason,
- * compression parameters can no longer be changed after loading a dictionary.
- * Note 3 :`dict` content will be copied internally.
- * Use experimental ZSTD_CCtx_loadDictionary_byReference() to reference content instead.
- * In such a case, dictionary buffer must outlive its users.
- * Note 4 : Use ZSTD_CCtx_loadDictionary_advanced()
- * to precisely select how dictionary content must be interpreted. */
-ZSTDLIB_API size_t ZSTD_CCtx_loadDictionary(ZSTD_CCtx* cctx, const void* dict, size_t dictSize);
-
-/*! ZSTD_CCtx_refCDict() :
- * Reference a prepared dictionary, to be used for all next compressed frames.
- * Note that compression parameters are enforced from within CDict,
- * and supersede any compression parameter previously set within CCtx.
- * The parameters ignored are labled as "superseded-by-cdict" in the ZSTD_cParameter enum docs.
- * The ignored parameters will be used again if the CCtx is returned to no-dictionary mode.
- * The dictionary will remain valid for future compressed frames using same CCtx.
- * @result : 0, or an error code (which can be tested with ZSTD_isError()).
- * Special : Referencing a NULL CDict means "return to no-dictionary mode".
- * Note 1 : Currently, only one dictionary can be managed.
- * Referencing a new dictionary effectively "discards" any previous one.
- * Note 2 : CDict is just referenced, its lifetime must outlive its usage within CCtx. */
-ZSTDLIB_API size_t ZSTD_CCtx_refCDict(ZSTD_CCtx* cctx, const ZSTD_CDict* cdict);
-
-/*! ZSTD_CCtx_refPrefix() :
- * Reference a prefix (single-usage dictionary) for next compressed frame.
- * A prefix is **only used once**. Tables are discarded at end of frame (ZSTD_e_end).
- * Decompression will need same prefix to properly regenerate data.
- * Compressing with a prefix is similar in outcome as performing a diff and compressing it,
- * but performs much faster, especially during decompression (compression speed is tunable with compression level).
- * @result : 0, or an error code (which can be tested with ZSTD_isError()).
- * Special: Adding any prefix (including NULL) invalidates any previous prefix or dictionary
- * Note 1 : Prefix buffer is referenced. It **must** outlive compression.
- * Its content must remain unmodified during compression.
- * Note 2 : If the intention is to diff some large src data blob with some prior version of itself,
- * ensure that the window size is large enough to contain the entire source.
- * See ZSTD_c_windowLog.
- * Note 3 : Referencing a prefix involves building tables, which are dependent on compression parameters.
- * It's a CPU consuming operation, with non-negligible impact on latency.
- * If there is a need to use the same prefix multiple times, consider loadDictionary instead.
- * Note 4 : By default, the prefix is interpreted as raw content (ZSTD_dm_rawContent).
- * Use experimental ZSTD_CCtx_refPrefix_advanced() to alter dictionary interpretation. */
-ZSTDLIB_API size_t ZSTD_CCtx_refPrefix(ZSTD_CCtx* cctx,
- const void* prefix, size_t prefixSize);
-
typedef enum {
ZSTD_reset_session_only = 1,
ZSTD_reset_parameters = 2,
*/
ZSTDLIB_API size_t ZSTD_DCtx_setParameter(ZSTD_DCtx* dctx, ZSTD_dParameter param, int value);
-/*! ZSTD_DCtx_loadDictionary() :
- * Create an internal DDict from dict buffer,
- * to be used to decompress next frames.
- * The dictionary remains valid for all future frames, until explicitly invalidated.
- * @result : 0, or an error code (which can be tested with ZSTD_isError()).
- * Special : Adding a NULL (or 0-size) dictionary invalidates any previous dictionary,
- * meaning "return to no-dictionary mode".
- * Note 1 : Loading a dictionary involves building tables,
- * which has a non-negligible impact on CPU usage and latency.
- * It's recommended to "load once, use many times", to amortize the cost
- * Note 2 :`dict` content will be copied internally, so `dict` can be released after loading.
- * Use ZSTD_DCtx_loadDictionary_byReference() to reference dictionary content instead.
- * Note 3 : Use ZSTD_DCtx_loadDictionary_advanced() to take control of
- * how dictionary content is loaded and interpreted.
- */
-ZSTDLIB_API size_t ZSTD_DCtx_loadDictionary(ZSTD_DCtx* dctx, const void* dict, size_t dictSize);
-
-/*! ZSTD_DCtx_refDDict() :
- * Reference a prepared dictionary, to be used to decompress next frames.
- * The dictionary remains active for decompression of future frames using same DCtx.
- * @result : 0, or an error code (which can be tested with ZSTD_isError()).
- * Note 1 : Currently, only one dictionary can be managed.
- * Referencing a new dictionary effectively "discards" any previous one.
- * Special: referencing a NULL DDict means "return to no-dictionary mode".
- * Note 2 : DDict is just referenced, its lifetime must outlive its usage from DCtx.
- */
-ZSTDLIB_API size_t ZSTD_DCtx_refDDict(ZSTD_DCtx* dctx, const ZSTD_DDict* ddict);
-
-/*! ZSTD_DCtx_refPrefix() :
- * Reference a prefix (single-usage dictionary) to decompress next frame.
- * This is the reverse operation of ZSTD_CCtx_refPrefix(),
- * and must use the same prefix as the one used during compression.
- * Prefix is **only used once**. Reference is discarded at end of frame.
- * End of frame is reached when ZSTD_decompressStream() returns 0.
- * @result : 0, or an error code (which can be tested with ZSTD_isError()).
- * Note 1 : Adding any prefix (including NULL) invalidates any previously set prefix or dictionary
- * Note 2 : Prefix buffer is referenced. It **must** outlive decompression.
- * Prefix buffer must remain unmodified up to the end of frame,
- * reached when ZSTD_decompressStream() returns 0.
- * Note 3 : By default, the prefix is treated as raw content (ZSTD_dm_rawContent).
- * Use ZSTD_CCtx_refPrefix_advanced() to alter dictMode (Experimental section)
- * Note 4 : Referencing a raw content prefix has almost no cpu nor memory cost.
- * A full dictionary is more costly, as it requires building tables.
- */
-ZSTDLIB_API size_t ZSTD_DCtx_refPrefix(ZSTD_DCtx* dctx,
- const void* prefix, size_t prefixSize);
-
/*! ZSTD_DCtx_reset() :
* Return a DCtx to clean state.
* Session and parameters can be reset jointly or separately.
ZSTD_inBuffer* input,
ZSTD_EndDirective endOp);
+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. */
+
+/*******************************************************************************
+ * This is a legacy streaming API, and can be replaced by ZSTD_CCtx_reset() and
+ * ZSTD_compressStream2(). It is redundent, but is still fully supported.
+ * Advanced parameters and dictionary compression can only be used through the
+ * new API.
+ ******************************************************************************/
+
/**
* Equivalent to:
*
/** Equivalent to ZSTD_compressStream2(zcs, output, &emptyInput, ZSTD_e_end). */
ZSTDLIB_API size_t ZSTD_endStream(ZSTD_CStream* zcs, ZSTD_outBuffer* output);
-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. */
-
/*-***************************************************************************
* Streaming decompression - HowTo
ZSTDLIB_API size_t ZSTD_DStreamInSize(void); /*!< recommended size for input buffer */
ZSTDLIB_API size_t ZSTD_DStreamOutSize(void); /*!< recommended size for output buffer. Guarantee to successfully flush at least one complete block in all circumstances. */
+
+/**************************
+* Simple dictionary API
+***************************/
+/*! ZSTD_compress_usingDict() :
+ * Compression at an explicit compression level using a Dictionary.
+ * A dictionary can be any arbitrary data segment (also called a prefix),
+ * or a buffer with specified information (see dictBuilder/zdict.h).
+ * Note : This function loads the dictionary, resulting in significant startup delay.
+ * It's intended for a dictionary used only once.
+ * Note 2 : When `dict == NULL || dictSize < 8` no dictionary is used. */
+ZSTDLIB_API size_t ZSTD_compress_usingDict(ZSTD_CCtx* ctx,
+ void* dst, size_t dstCapacity,
+ const void* src, size_t srcSize,
+ const void* dict,size_t dictSize,
+ int compressionLevel);
+
+/*! ZSTD_decompress_usingDict() :
+ * Decompression using a known Dictionary.
+ * Dictionary must be identical to the one used during compression.
+ * Note : This function loads the dictionary, resulting in significant startup delay.
+ * It's intended for a dictionary used only once.
+ * Note : When `dict == NULL || dictSize < 8` no dictionary is used. */
+ZSTDLIB_API size_t ZSTD_decompress_usingDict(ZSTD_DCtx* dctx,
+ void* dst, size_t dstCapacity,
+ const void* src, size_t srcSize,
+ const void* dict,size_t dictSize);
+
+
+/***********************************
+ * Bulk processing dictionary API
+ **********************************/
+typedef struct ZSTD_CDict_s ZSTD_CDict;
+
+/*! ZSTD_createCDict() :
+ * When compressing multiple messages / blocks using the same dictionary, it's recommended to load it only once.
+ * ZSTD_createCDict() will create a digested dictionary, ready to start future compression operations without startup cost.
+ * ZSTD_CDict can be created once and shared by multiple threads concurrently, since its usage is read-only.
+ * `dictBuffer` can be released after ZSTD_CDict creation, because its content is copied within CDict.
+ * Consider experimental function `ZSTD_createCDict_byReference()` if you prefer to not duplicate `dictBuffer` content.
+ * Note : A ZSTD_CDict can be created from an empty dictBuffer, but it is inefficient when used to compress small data. */
+ZSTDLIB_API ZSTD_CDict* ZSTD_createCDict(const void* dictBuffer, size_t dictSize,
+ int compressionLevel);
+
+/*! ZSTD_freeCDict() :
+ * Function frees memory allocated by ZSTD_createCDict(). */
+ZSTDLIB_API size_t ZSTD_freeCDict(ZSTD_CDict* CDict);
+
+/*! ZSTD_compress_usingCDict() :
+ * Compression using a digested Dictionary.
+ * Recommended when same dictionary is used multiple times.
+ * Note : compression level is _decided at dictionary creation time_,
+ * and frame parameters are hardcoded (dictID=yes, contentSize=yes, checksum=no) */
+ZSTDLIB_API size_t ZSTD_compress_usingCDict(ZSTD_CCtx* cctx,
+ void* dst, size_t dstCapacity,
+ const void* src, size_t srcSize,
+ const ZSTD_CDict* cdict);
+
+
+typedef struct ZSTD_DDict_s ZSTD_DDict;
+
+/*! ZSTD_createDDict() :
+ * Create a digested dictionary, ready to start decompression operation without startup delay.
+ * dictBuffer can be released after DDict creation, as its content is copied inside DDict. */
+ZSTDLIB_API ZSTD_DDict* ZSTD_createDDict(const void* dictBuffer, size_t dictSize);
+
+/*! ZSTD_freeDDict() :
+ * Function frees memory allocated with ZSTD_createDDict() */
+ZSTDLIB_API size_t ZSTD_freeDDict(ZSTD_DDict* ddict);
+
+/*! ZSTD_decompress_usingDDict() :
+ * Decompression using a digested Dictionary.
+ * Recommended when same dictionary is used multiple times. */
+ZSTDLIB_API size_t ZSTD_decompress_usingDDict(ZSTD_DCtx* dctx,
+ void* dst, size_t dstCapacity,
+ const void* src, size_t srcSize,
+ const ZSTD_DDict* ddict);
+
+
+/*******************************************************************************
+ * Advanced dictionary and prefix API
+ *
+ * This API allows dictionaries to be used with ZSTD_compress2(),
+ * ZSTD_compressStream2(), and ZSTD_decompress(). Dictionaries are sticky, and
+ * only reset with the context is reset with ZSTD_reset_parameters or
+ * ZSTD_reset_session_and_parameters. Prefixes are single-use.
+ ******************************************************************************/
+
+
+/*! ZSTD_CCtx_loadDictionary() :
+ * Create an internal CDict from `dict` buffer.
+ * Decompression will have to use same dictionary.
+ * @result : 0, or an error code (which can be tested with ZSTD_isError()).
+ * Special: Loading a NULL (or 0-size) dictionary invalidates previous dictionary,
+ * meaning "return to no-dictionary mode".
+ * Note 1 : Dictionary is sticky, it will be used for all future compressed frames.
+ * To return to "no-dictionary" situation, load a NULL dictionary (or reset parameters).
+ * Note 2 : Loading a dictionary involves building tables.
+ * It's also a CPU consuming operation, with non-negligible impact on latency.
+ * Tables are dependent on compression parameters, and for this reason,
+ * compression parameters can no longer be changed after loading a dictionary.
+ * Note 3 :`dict` content will be copied internally.
+ * Use experimental ZSTD_CCtx_loadDictionary_byReference() to reference content instead.
+ * In such a case, dictionary buffer must outlive its users.
+ * Note 4 : Use ZSTD_CCtx_loadDictionary_advanced()
+ * to precisely select how dictionary content must be interpreted. */
+ZSTDLIB_API size_t ZSTD_CCtx_loadDictionary(ZSTD_CCtx* cctx, const void* dict, size_t dictSize);
+
+/*! ZSTD_CCtx_refCDict() :
+ * Reference a prepared dictionary, to be used for all next compressed frames.
+ * Note that compression parameters are enforced from within CDict,
+ * and supersede any compression parameter previously set within CCtx.
+ * The parameters ignored are labled as "superseded-by-cdict" in the ZSTD_cParameter enum docs.
+ * The ignored parameters will be used again if the CCtx is returned to no-dictionary mode.
+ * The dictionary will remain valid for future compressed frames using same CCtx.
+ * @result : 0, or an error code (which can be tested with ZSTD_isError()).
+ * Special : Referencing a NULL CDict means "return to no-dictionary mode".
+ * Note 1 : Currently, only one dictionary can be managed.
+ * Referencing a new dictionary effectively "discards" any previous one.
+ * Note 2 : CDict is just referenced, its lifetime must outlive its usage within CCtx. */
+ZSTDLIB_API size_t ZSTD_CCtx_refCDict(ZSTD_CCtx* cctx, const ZSTD_CDict* cdict);
+
+/*! ZSTD_CCtx_refPrefix() :
+ * Reference a prefix (single-usage dictionary) for next compressed frame.
+ * A prefix is **only used once**. Tables are discarded at end of frame (ZSTD_e_end).
+ * Decompression will need same prefix to properly regenerate data.
+ * Compressing with a prefix is similar in outcome as performing a diff and compressing it,
+ * but performs much faster, especially during decompression (compression speed is tunable with compression level).
+ * @result : 0, or an error code (which can be tested with ZSTD_isError()).
+ * Special: Adding any prefix (including NULL) invalidates any previous prefix or dictionary
+ * Note 1 : Prefix buffer is referenced. It **must** outlive compression.
+ * Its content must remain unmodified during compression.
+ * Note 2 : If the intention is to diff some large src data blob with some prior version of itself,
+ * ensure that the window size is large enough to contain the entire source.
+ * See ZSTD_c_windowLog.
+ * Note 3 : Referencing a prefix involves building tables, which are dependent on compression parameters.
+ * It's a CPU consuming operation, with non-negligible impact on latency.
+ * If there is a need to use the same prefix multiple times, consider loadDictionary instead.
+ * Note 4 : By default, the prefix is interpreted as raw content (ZSTD_dm_rawContent).
+ * Use experimental ZSTD_CCtx_refPrefix_advanced() to alter dictionary interpretation. */
+ZSTDLIB_API size_t ZSTD_CCtx_refPrefix(ZSTD_CCtx* cctx,
+ const void* prefix, size_t prefixSize);
+
+/*! ZSTD_DCtx_loadDictionary() :
+ * Create an internal DDict from dict buffer,
+ * to be used to decompress next frames.
+ * The dictionary remains valid for all future frames, until explicitly invalidated.
+ * @result : 0, or an error code (which can be tested with ZSTD_isError()).
+ * Special : Adding a NULL (or 0-size) dictionary invalidates any previous dictionary,
+ * meaning "return to no-dictionary mode".
+ * Note 1 : Loading a dictionary involves building tables,
+ * which has a non-negligible impact on CPU usage and latency.
+ * It's recommended to "load once, use many times", to amortize the cost
+ * Note 2 :`dict` content will be copied internally, so `dict` can be released after loading.
+ * Use ZSTD_DCtx_loadDictionary_byReference() to reference dictionary content instead.
+ * Note 3 : Use ZSTD_DCtx_loadDictionary_advanced() to take control of
+ * how dictionary content is loaded and interpreted.
+ */
+ZSTDLIB_API size_t ZSTD_DCtx_loadDictionary(ZSTD_DCtx* dctx, const void* dict, size_t dictSize);
+
+/*! ZSTD_DCtx_refDDict() :
+ * Reference a prepared dictionary, to be used to decompress next frames.
+ * The dictionary remains active for decompression of future frames using same DCtx.
+ * @result : 0, or an error code (which can be tested with ZSTD_isError()).
+ * Note 1 : Currently, only one dictionary can be managed.
+ * Referencing a new dictionary effectively "discards" any previous one.
+ * Special: referencing a NULL DDict means "return to no-dictionary mode".
+ * Note 2 : DDict is just referenced, its lifetime must outlive its usage from DCtx.
+ */
+ZSTDLIB_API size_t ZSTD_DCtx_refDDict(ZSTD_DCtx* dctx, const ZSTD_DDict* ddict);
+
+/*! ZSTD_DCtx_refPrefix() :
+ * Reference a prefix (single-usage dictionary) to decompress next frame.
+ * This is the reverse operation of ZSTD_CCtx_refPrefix(),
+ * and must use the same prefix as the one used during compression.
+ * Prefix is **only used once**. Reference is discarded at end of frame.
+ * End of frame is reached when ZSTD_decompressStream() returns 0.
+ * @result : 0, or an error code (which can be tested with ZSTD_isError()).
+ * Note 1 : Adding any prefix (including NULL) invalidates any previously set prefix or dictionary
+ * Note 2 : Prefix buffer is referenced. It **must** outlive decompression.
+ * Prefix buffer must remain unmodified up to the end of frame,
+ * reached when ZSTD_decompressStream() returns 0.
+ * Note 3 : By default, the prefix is treated as raw content (ZSTD_dm_rawContent).
+ * Use ZSTD_CCtx_refPrefix_advanced() to alter dictMode (Experimental section)
+ * Note 4 : Referencing a raw content prefix has almost no cpu nor memory cost.
+ * A full dictionary is more costly, as it requires building tables.
+ */
+ZSTDLIB_API size_t ZSTD_DCtx_refPrefix(ZSTD_DCtx* dctx,
+ const void* prefix, size_t prefixSize);
+
/* === Memory management === */
/*! ZSTD_sizeof_*() :