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Merge branch 'dev' into shorterTests

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fixed conflicts
This commit is contained in:
Yann Collet
2017-09-28 12:19:28 -07:00
parent bbef058ae6 824f75ea7c
commit e4ec427720
25 changed files with 933 additions and 420 deletions
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lib/zstd.h
+195 -57
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@@ -395,11 +395,12 @@ ZSTDLIB_API size_t ZSTD_DStreamOutSize(void); /*!< recommended size for output
#define ZSTD_LDM_MINMATCH_MAX 4096
#define ZSTD_LDM_BUCKETSIZELOG_MAX 8
#define ZSTD_FRAMEHEADERSIZE_MAX 18 /* for static allocation */
#define ZSTD_FRAMEHEADERSIZE_MIN 6
static const size_t ZSTD_frameHeaderSize_prefix = 5; /* minimum input size to know frame header size */
static const size_t ZSTD_frameHeaderSize_max = ZSTD_FRAMEHEADERSIZE_MAX;
#define ZSTD_FRAMEHEADERSIZE_PREFIX 5 /* minimum input size to know frame header size */
#define ZSTD_FRAMEHEADERSIZE_MIN 6
#define ZSTD_FRAMEHEADERSIZE_MAX 18 /* for static allocation */
static const size_t ZSTD_frameHeaderSize_prefix = ZSTD_FRAMEHEADERSIZE_PREFIX;
static const size_t ZSTD_frameHeaderSize_min = ZSTD_FRAMEHEADERSIZE_MIN;
static const size_t ZSTD_frameHeaderSize_max = ZSTD_FRAMEHEADERSIZE_MAX;
static const size_t ZSTD_skippableHeaderSize = 8; /* magic number + skippable frame length */
@@ -486,7 +487,7 @@ ZSTDLIB_API size_t ZSTD_frameHeaderSize(const void* src, size_t srcSize);
/*! ZSTD_sizeof_*() :
* These functions give the current memory usage of selected object.
* Object memory usage can evolve if it's re-used multiple times. */
* Object memory usage can evolve when re-used multiple times. */
ZSTDLIB_API size_t ZSTD_sizeof_CCtx(const ZSTD_CCtx* cctx);
ZSTDLIB_API size_t ZSTD_sizeof_DCtx(const ZSTD_DCtx* dctx);
ZSTDLIB_API size_t ZSTD_sizeof_CStream(const ZSTD_CStream* zcs);
@@ -499,21 +500,21 @@ ZSTDLIB_API size_t ZSTD_sizeof_DDict(const ZSTD_DDict* ddict);
* of a future {D,C}Ctx, before its creation.
* ZSTD_estimateCCtxSize() will provide a budget large enough for any compression level up to selected one.
* It will also consider src size to be arbitrarily "large", which is worst case.
* If srcSize is known to always be small, ZSTD_estimateCCtxSize_advanced_usingCParams() can provide a tighter estimation.
* ZSTD_estimateCCtxSize_advanced_usingCParams() can be used in tandem with ZSTD_getCParams() to create cParams from compressionLevel.
* ZSTD_estimateCCtxSize_advanced_usingCCtxParams() can be used in tandem with ZSTD_CCtxParam_setParameter(). Only single-threaded compression is supported. This function will return an error code if ZSTD_p_nbThreads is > 1.
* If srcSize is known to always be small, ZSTD_estimateCCtxSize_usingCParams() can provide a tighter estimation.
* ZSTD_estimateCCtxSize_usingCParams() can be used in tandem with ZSTD_getCParams() to create cParams from compressionLevel.
* ZSTD_estimateCCtxSize_usingCCtxParams() can be used in tandem with ZSTD_CCtxParam_setParameter(). Only single-threaded compression is supported. This function will return an error code if ZSTD_p_nbThreads is > 1.
* Note : CCtx estimation is only correct for single-threaded compression */
ZSTDLIB_API size_t ZSTD_estimateCCtxSize(int compressionLevel);
ZSTDLIB_API size_t ZSTD_estimateCCtxSize_advanced_usingCParams(ZSTD_compressionParameters cParams);
ZSTDLIB_API size_t ZSTD_estimateCCtxSize_advanced_usingCCtxParams(const ZSTD_CCtx_params* params);
ZSTDLIB_API size_t ZSTD_estimateCCtxSize_usingCParams(ZSTD_compressionParameters cParams);
ZSTDLIB_API size_t ZSTD_estimateCCtxSize_usingCCtxParams(const ZSTD_CCtx_params* params);
ZSTDLIB_API size_t ZSTD_estimateDCtxSize(void);
/*! ZSTD_estimateCStreamSize() :
* ZSTD_estimateCStreamSize() will provide a budget large enough for any compression level up to selected one.
* It will also consider src size to be arbitrarily "large", which is worst case.
* If srcSize is known to always be small, ZSTD_estimateCStreamSize_advanced_usingCParams() can provide a tighter estimation.
* ZSTD_estimateCStreamSize_advanced_usingCParams() can be used in tandem with ZSTD_getCParams() to create cParams from compressionLevel.
* ZSTD_estimateCStreamSize_advanced_usingCCtxParams() can be used in tandem with ZSTD_CCtxParam_setParameter(). Only single-threaded compression is supported. This function will return an error code if ZSTD_p_nbThreads is set to a value > 1.
* If srcSize is known to always be small, ZSTD_estimateCStreamSize_usingCParams() can provide a tighter estimation.
* ZSTD_estimateCStreamSize_usingCParams() can be used in tandem with ZSTD_getCParams() to create cParams from compressionLevel.
* ZSTD_estimateCStreamSize_usingCCtxParams() can be used in tandem with ZSTD_CCtxParam_setParameter(). Only single-threaded compression is supported. This function will return an error code if ZSTD_p_nbThreads is set to a value > 1.
* Note : CStream estimation is only correct for single-threaded compression.
* ZSTD_DStream memory budget depends on window Size.
* This information can be passed manually, using ZSTD_estimateDStreamSize,
@@ -522,14 +523,14 @@ ZSTDLIB_API size_t ZSTD_estimateDCtxSize(void);
* an internal ?Dict will be created, which additional size is not estimated here.
* In this case, get total size by adding ZSTD_estimate?DictSize */
ZSTDLIB_API size_t ZSTD_estimateCStreamSize(int compressionLevel);
ZSTDLIB_API size_t ZSTD_estimateCStreamSize_advanced_usingCParams(ZSTD_compressionParameters cParams);
ZSTDLIB_API size_t ZSTD_estimateCStreamSize_advanced_usingCCtxParams(const ZSTD_CCtx_params* params);
ZSTDLIB_API size_t ZSTD_estimateCStreamSize_usingCParams(ZSTD_compressionParameters cParams);
ZSTDLIB_API size_t ZSTD_estimateCStreamSize_usingCCtxParams(const ZSTD_CCtx_params* params);
ZSTDLIB_API size_t ZSTD_estimateDStreamSize(size_t windowSize);
ZSTDLIB_API size_t ZSTD_estimateDStreamSize_fromFrame(const void* src, size_t srcSize);
typedef enum {
ZSTD_dlm_byCopy = 0, /* Copy dictionary content internally. */
ZSTD_dlm_byRef, /* Reference dictionary content -- the dictionary buffer must outlives its users. */
ZSTD_dlm_byCopy = 0, /**< Copy dictionary content internally */
ZSTD_dlm_byRef, /**< Reference dictionary content -- the dictionary buffer must outlive its users. */
} ZSTD_dictLoadMethod_e;
/*! ZSTD_estimate?DictSize() :
@@ -747,12 +748,12 @@ ZSTDLIB_API size_t ZSTD_resetCStream(ZSTD_CStream* zcs, unsigned long long pledg
/*===== Advanced Streaming decompression functions =====*/
typedef enum { DStream_p_maxWindowSize } ZSTD_DStreamParameter_e;
ZSTDLIB_API ZSTD_DStream* ZSTD_createDStream_advanced(ZSTD_customMem customMem);
ZSTDLIB_API ZSTD_DStream* ZSTD_initStaticDStream(void* workspace, size_t workspaceSize); /**< same as ZSTD_initStaticDCtx() */
ZSTDLIB_API size_t ZSTD_setDStreamParameter(ZSTD_DStream* zds, ZSTD_DStreamParameter_e paramType, unsigned paramValue);
ZSTDLIB_API size_t ZSTD_initDStream_usingDict(ZSTD_DStream* zds, const void* dict, size_t dictSize); /**< note: a dict will not be used if dict == NULL or dictSize < 8 */
ZSTDLIB_API size_t ZSTD_initDStream_usingDDict(ZSTD_DStream* zds, const ZSTD_DDict* ddict); /**< note : ddict will just be referenced, and must outlive decompression session */
typedef enum { DStream_p_maxWindowSize } ZSTD_DStreamParameter_e;
ZSTDLIB_API size_t ZSTD_setDStreamParameter(ZSTD_DStream* zds, ZSTD_DStreamParameter_e paramType, unsigned paramValue); /* obsolete : this API will be removed in a future version */
ZSTDLIB_API size_t ZSTD_initDStream_usingDict(ZSTD_DStream* zds, const void* dict, size_t dictSize); /**< note: no dictionary will be used if dict == NULL or dictSize < 8 */
ZSTDLIB_API size_t ZSTD_initDStream_usingDDict(ZSTD_DStream* zds, const ZSTD_DDict* ddict); /**< note : ddict is referenced, it must outlive decompression session */
ZSTDLIB_API size_t ZSTD_resetDStream(ZSTD_DStream* zds); /**< re-use decompression parameters from previous init; saves dictionary loading */
@@ -760,8 +761,8 @@ ZSTDLIB_API size_t ZSTD_resetDStream(ZSTD_DStream* zds); /**< re-use decompress
* Buffer-less and synchronous inner streaming functions
*
* This is an advanced API, giving full control over buffer management, for users which need direct control over memory.
* But it's also a complex one, with many restrictions (documented below).
* Prefer using normal streaming API for an easier experience
* But it's also a complex one, with several restrictions, documented below.
* Prefer normal streaming API for an easier experience.
********************************************************************* */
/**
@@ -778,8 +779,8 @@ ZSTDLIB_API size_t ZSTD_resetDStream(ZSTD_DStream* zds); /**< re-use decompress
Then, consume your input using ZSTD_compressContinue().
There are some important considerations to keep in mind when using this advanced function :
- ZSTD_compressContinue() has no internal buffer. It uses externally provided buffer only.
- Interface is synchronous : input is consumed entirely and produce 1+ (or more) compressed blocks.
- ZSTD_compressContinue() has no internal buffer. It uses externally provided buffers only.
- Interface is synchronous : input is consumed entirely and produces 1+ compressed blocks.
- Caller must ensure there is enough space in `dst` to store compressed data under worst case scenario.
Worst case evaluation is provided by ZSTD_compressBound().
ZSTD_compressContinue() doesn't guarantee recover after a failed compression.
@@ -790,9 +791,9 @@ ZSTDLIB_API size_t ZSTD_resetDStream(ZSTD_DStream* zds); /**< re-use decompress
Finish a frame with ZSTD_compressEnd(), which will write the last block(s) and optional checksum.
It's possible to use srcSize==0, in which case, it will write a final empty block to end the frame.
Without last block mark, frames will be considered unfinished (corrupted) by decoders.
Without last block mark, frames are considered unfinished (hence corrupted) by compliant decoders.
`ZSTD_CCtx` object can be re-used (ZSTD_compressBegin()) to compress some new frame.
`ZSTD_CCtx` object can be re-used (ZSTD_compressBegin()) to compress again.
*/
/*===== Buffer-less streaming compression functions =====*/
@@ -908,33 +909,55 @@ ZSTDLIB_API ZSTD_nextInputType_e ZSTD_nextInputType(ZSTD_DCtx* dctx);
/*=== New advanced API (experimental, and compression only) ===*/
/* ============================================ */
/** New advanced API (experimental) */
/* ============================================ */
/* notes on API design :
* In this proposal, parameters are pushed one by one into an existing CCtx,
* In this proposal, parameters are pushed one by one into an existing context,
* and then applied on all subsequent compression jobs.
* When no parameter is ever provided, CCtx is created with compression level ZSTD_CLEVEL_DEFAULT.
*
* This API is intended to replace all others experimental API.
* It can basically do all other use cases, and even new ones.
* It stands a good chance to become "stable",
* after a reasonable testing period.
* In constrast with _advanced() variants, it stands a reasonable chance to become "stable",
* after a good testing period.
*/
/* note on naming convention :
* Initially, the API favored names like ZSTD_setCCtxParameter() .
* In this proposal, convention is changed towards ZSTD_CCtx_setParameter() .
* The main driver is that it identifies more clearly the target object type.
* It feels clearer in light of potential variants :
* It feels clearer when considering multiple targets :
* ZSTD_CDict_setParameter() (rather than ZSTD_setCDictParameter())
* ZSTD_DCtx_setParameter() (rather than ZSTD_setDCtxParameter() )
* Left variant feels easier to distinguish.
* ZSTD_CCtxParams_setParameter() (rather than ZSTD_setCCtxParamsParameter() )
* etc...
*/
/* note on enum design :
* All enum will be manually set to explicit values before reaching "stable API" status */
* All enum will be pinned to explicit values before reaching "stable API" status */
typedef enum {
/* Question : should we have a format ZSTD_f_auto ?
* For the time being, it would mean exactly the same as ZSTD_f_zstd1.
* But, in the future, should several formats be supported,
* on the compression side, it would mean "default format".
* On the decompression side, it would mean "multi format",
* and ZSTD_f_zstd1 could be reserved to mean "accept *only* zstd frames".
* Since meaning is a little different, another option could be to define different enums for compression and decompression.
* This question could be kept for later, when there are actually multiple formats to support,
* but there is also the question of pinning enum values, and pinning value `0` is especially important */
ZSTD_f_zstd1 = 0, /* zstd frame format, specified in zstd_compression_format.md (default) */
ZSTD_f_zstd1_magicless, /* Variant of zstd frame format, without initial 4-bytes magic number.
* Useful to save 4 bytes per generated frame.
* Decoder cannot recognise automatically this format, requiring instructions. */
} ZSTD_format_e;
typedef enum {
/* compression format */
ZSTD_p_format = 10, /* See ZSTD_format_e enum definition.
* Cast selected format as unsigned for ZSTD_CCtx_setParameter() compatibility. */
/* compression parameters */
ZSTD_p_compressionLevel=100, /* Update all compression parameters according to pre-defined cLevel table
* Default level is ZSTD_CLEVEL_DEFAULT==3.
@@ -1105,15 +1128,15 @@ ZSTDLIB_API size_t ZSTD_CCtx_refPrefix_advanced(ZSTD_CCtx* cctx, const void* pre
typedef enum {
ZSTD_e_continue=0, /* collect more data, encoder transparently decides when to output result, for optimal conditions */
ZSTD_e_flush, /* flush any data provided so far - frame will continue, future data can still reference previous data for better compression */
ZSTD_e_end /* flush any remaining data and ends current frame. Any future compression starts a new frame. */
ZSTD_e_end /* flush any remaining data and close current frame. Any additional data starts a new frame. */
} ZSTD_EndDirective;
/*! ZSTD_compress_generic() :
* Behave about the same as ZSTD_compressStream. To note :
* - Compression parameters are pushed into CCtx before starting compression, using ZSTD_CCtx_setParameter()
* - Compression parameters cannot be changed once compression is started.
* - *dstPos must be <= dstCapacity, *srcPos must be <= srcSize
* - *dspPos and *srcPos will be updated. They are guaranteed to remain below their respective limit.
* - outpot->pos must be <= dstCapacity, input->pos must be <= srcSize
* - outpot->pos and input->pos will be updated. They are guaranteed to remain below their respective limit.
* - @return provides the minimum amount of data still to flush from internal buffers
* or an error code, which can be tested using ZSTD_isError().
* if @return != 0, flush is not fully completed, there is some data left within internal buffers.
@@ -1132,6 +1155,7 @@ ZSTDLIB_API size_t ZSTD_compress_generic (ZSTD_CCtx* cctx,
* Useful after an error, or to interrupt an ongoing compression job and start a new one.
* Any internal data not yet flushed is cancelled.
* Dictionary (if any) is dropped.
* All parameters are back to default values.
* It's possible to modify compression parameters after a reset.
*/
ZSTDLIB_API void ZSTD_CCtx_reset(ZSTD_CCtx* cctx); /* Not ready yet ! */
@@ -1140,30 +1164,33 @@ ZSTDLIB_API void ZSTD_CCtx_reset(ZSTD_CCtx* cctx); /* Not ready yet ! */
/*! ZSTD_compress_generic_simpleArgs() :
* Same as ZSTD_compress_generic(),
* but using only integral types as arguments.
* Argument list is larger and less expressive than ZSTD_{in,out}Buffer,
* Argument list is larger than ZSTD_{in,out}Buffer,
* but can be helpful for binders from dynamic languages
* which have troubles handling structures containing memory pointers.
*/
size_t ZSTD_compress_generic_simpleArgs (
ZSTDLIB_API size_t ZSTD_compress_generic_simpleArgs (
ZSTD_CCtx* cctx,
void* dst, size_t dstCapacity, size_t* dstPos,
const void* src, size_t srcSize, size_t* srcPos,
ZSTD_EndDirective endOp);
/** ZSTD_CCtx_params
*
/*! ZSTD_CCtx_params :
* Quick howto :
* - ZSTD_createCCtxParams() : Create a ZSTD_CCtx_params structure
* - ZSTD_CCtxParam_setParameter() : Push parameters one by one into an
* existing ZSTD_CCtx_params structure. This is similar to
* ZSTD_CCtx_setParameter().
* - ZSTD_CCtx_setParametersUsingCCtxParams() : Apply parameters to an existing CCtx. These
* parameters will be applied to all subsequent compression jobs.
* - ZSTD_CCtxParam_setParameter() : Push parameters one by one into
* an existing ZSTD_CCtx_params structure.
* This is similar to
* ZSTD_CCtx_setParameter().
* - ZSTD_CCtx_setParametersUsingCCtxParams() : Apply parameters to
* an existing CCtx.
* These parameters will be applied to
* all subsequent compression jobs.
* - ZSTD_compress_generic() : Do compression using the CCtx.
* - ZSTD_freeCCtxParams() : Free the memory.
*
* This can be used with ZSTD_estimateCCtxSize_opaque() for static allocation
* for single-threaded compression.
* This can be used with ZSTD_estimateCCtxSize_advanced_usingCCtxParams()
* for static allocation for single-threaded compression.
*/
ZSTDLIB_API ZSTD_CCtx_params* ZSTD_createCCtxParams(void);
@@ -1191,22 +1218,133 @@ ZSTDLIB_API size_t ZSTD_freeCCtxParams(ZSTD_CCtx_params* params);
* Set one compression parameter, selected by enum ZSTD_cParameter.
* Parameters must be applied to a ZSTD_CCtx using ZSTD_CCtx_setParametersUsingCCtxParams().
* Note : when `value` is an enum, cast it to unsigned for proper type checking.
* @result : 0, or an error code (which can be tested with ZSTD_isError()).
* @result : 0, or an error code (which can be tested with ZSTD_isError()).
*/
ZSTDLIB_API size_t ZSTD_CCtxParam_setParameter(ZSTD_CCtx_params* params, ZSTD_cParameter param, unsigned value);
/*! ZSTD_CCtx_setParametersUsingCCtxParams() :
* Apply a set of ZSTD_CCtx_params to the compression context.
* This must be done before the dictionary is loaded.
* The pledgedSrcSize is treated as unknown.
* Multithreading parameters are applied only if nbThreads > 1.
* Apply a set of ZSTD_CCtx_params to the compression context.
* This must be done before the dictionary is loaded.
* The pledgedSrcSize is treated as unknown.
* Multithreading parameters are applied only if nbThreads > 1.
*/
ZSTDLIB_API size_t ZSTD_CCtx_setParametersUsingCCtxParams(
ZSTD_CCtx* cctx, const ZSTD_CCtx_params* params);
/**
Block functions
/*=== Advanced parameters for decompression API ===*/
/* The following parameters must be set after creating a ZSTD_DCtx* (or ZSTD_DStream*) object,
* but before starting decompression of a frame.
*/
/*! ZSTD_DCtx_loadDictionary() :
* Create an internal DDict from dict buffer,
* to be used to decompress next frames.
* @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 : `dict` content will be copied internally.
* Use ZSTD_DCtx_loadDictionary_byReference()
* to reference dictionary content instead.
* In which case, the dictionary buffer must outlive its users.
* Note 2 : Loading a dictionary involves building tables,
* which has a non-negligible impact on CPU usage and latency.
* Note 3 : Use ZSTD_DCtx_loadDictionary_advanced() to select
* how dictionary content will be interpreted and loaded.
*/
ZSTDLIB_API size_t ZSTD_DCtx_loadDictionary(ZSTD_DCtx* dctx, const void* dict, size_t dictSize); /* not implemented */
ZSTDLIB_API size_t ZSTD_DCtx_loadDictionary_byReference(ZSTD_DCtx* dctx, const void* dict, size_t dictSize); /* not implemented */
ZSTDLIB_API size_t ZSTD_DCtx_loadDictionary_advanced(ZSTD_DCtx* dctx, const void* dict, size_t dictSize, ZSTD_dictLoadMethod_e dictLoadMethod, ZSTD_dictMode_e dictMode); /* not implemented */
/*! 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 : adding 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); /* not implemented */
/*! ZSTD_DCtx_refPrefix() :
* Reference a prefix (single-usage dictionary) for next compression job.
* Prefix is **only used once**. It must be explicitly referenced before each frame.
* If there is a need to use same prefix multiple times, consider embedding it into a ZSTD_DDict instead.
* @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 compression job.
* Note 3 : By default, the prefix is treated as raw content (ZSTD_dm_rawContent).
* Use ZSTD_CCtx_refPrefix_advanced() to alter dictMode.
* Note 4 : Referencing a raw content prefix has almost no cpu nor memory cost.
*/
ZSTDLIB_API size_t ZSTD_DCtx_refPrefix(ZSTD_DCtx* dctx, const void* prefix, size_t prefixSize); /* not implemented */
ZSTDLIB_API size_t ZSTD_DCtx_refPrefix_advanced(ZSTD_DCtx* dctx, const void* prefix, size_t prefixSize, ZSTD_dictMode_e dictMode); /* not implemented */
/*! ZSTD_DCtx_setMaxWindowSize() :
* Refuses allocating internal buffers for frames requiring a window size larger than provided limit.
* This is useful to prevent a decoder context from reserving too much memory for itself (potential attack scenario).
* This parameter is only useful in streaming mode, since no internal buffer is allocated in direct mode.
* By default, a decompression context accepts all window sizes <= (1 << ZSTD_WINDOWLOG_MAX)
* @return : 0, or an error code (which can be tested using ZSTD_isError()).
*/
ZSTDLIB_API size_t ZSTD_DCtx_setMaxWindowSize(ZSTD_DCtx* dctx, size_t maxWindowSize);
/*! ZSTD_DCtx_setFormat() :
* Instruct the decoder context about what kind of data to decode next.
* This instruction is mandatory to decode data without a fully-formed header,
* such ZSTD_f_zstd1_magicless for example.
* @return : 0, or an error code (which can be tested using ZSTD_isError()).
*/
ZSTDLIB_API size_t ZSTD_DCtx_setFormat(ZSTD_DCtx* dctx, ZSTD_format_e format);
/*! ZSTD_decompress_generic() :
* Behave the same as ZSTD_decompressStream.
* Decompression parameters cannot be changed once decompression is started.
* @return : an error code, which can be tested using ZSTD_isError()
* if >0, a hint, nb of expected input bytes for next invocation.
* `0` means : a frame has just been fully decoded and flushed.
*/
ZSTDLIB_API size_t ZSTD_decompress_generic(ZSTD_DCtx* dctx,
ZSTD_outBuffer* output,
ZSTD_inBuffer* input);
/*! ZSTD_decompress_generic_simpleArgs() :
* Same as ZSTD_decompress_generic(),
* but using only integral types as arguments.
* Argument list is larger than ZSTD_{in,out}Buffer,
* but can be helpful for binders from dynamic languages
* which have troubles handling structures containing memory pointers.
*/
ZSTDLIB_API size_t ZSTD_decompress_generic_simpleArgs (
ZSTD_DCtx* dctx,
void* dst, size_t dstCapacity, size_t* dstPos,
const void* src, size_t srcSize, size_t* srcPos);
/*! ZSTD_DCtx_reset() :
* Return a DCtx to clean state.
* If a decompression was ongoing, any internal data not yet flushed is cancelled.
* All parameters are back to default values, including sticky ones.
* Dictionary (if any) is dropped.
* Parameters can be modified again after a reset.
*/
ZSTDLIB_API void ZSTD_DCtx_reset(ZSTD_DCtx* dctx);
/* ============================ */
/** Block level API */
/* ============================ */
/*!
Block functions produce and decode raw zstd blocks, without frame metadata.
Frame metadata cost is typically ~18 bytes, which can be non-negligible for very small blocks (< 100 bytes).
User will have to take in charge required information to regenerate data, such as compressed and content sizes.
@@ -1218,7 +1356,7 @@ ZSTDLIB_API size_t ZSTD_CCtx_setParametersUsingCCtxParams(
+ compression : any ZSTD_compressBegin*() variant, including with dictionary
+ decompression : any ZSTD_decompressBegin*() variant, including with dictionary
+ copyCCtx() and copyDCtx() can be used too
- Block size is limited, it must be <= ZSTD_getBlockSize() <= ZSTD_BLOCKSIZE_MAX
- Block size is limited, it must be <= ZSTD_getBlockSize() <= ZSTD_BLOCKSIZE_MAX == 128 KB
+ If input is larger than a block size, it's necessary to split input data into multiple blocks
+ For inputs larger than a single block size, consider using the regular ZSTD_compress() instead.
Frame metadata is not that costly, and quickly becomes negligible as source size grows larger.