mirror of
https://github.com/Xevion/easy7zip.git
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zstd release 0.8.0
- made an extra zstd.mak file - removed Format7zZStd - SFXSetup also has zstd now - the big 7z.dll is backward compatible to: 0.5 .. 0.7 - the small 7za.dll has only support for zstd 0.8
This commit is contained in:
185
C/zstd/zstd.h
185
C/zstd/zstd.h
@@ -36,15 +36,11 @@
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extern "C" {
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#endif
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/*-*************************************
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* Dependencies
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***************************************/
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/*====== Dependency ======*/
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#include <stddef.h> /* size_t */
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/*-***************************************************************
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* Export parameters
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*****************************************************************/
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/*====== Export for Windows ======*/
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/*!
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* ZSTD_DLL_EXPORT :
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* Enable exporting of functions when building a Windows DLL
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@@ -56,12 +52,10 @@ extern "C" {
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#endif
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/* *************************************
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* Version
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***************************************/
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/*====== Version ======*/
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#define ZSTD_VERSION_MAJOR 0
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#define ZSTD_VERSION_MINOR 7
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#define ZSTD_VERSION_RELEASE 4
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#define ZSTD_VERSION_MINOR 8
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#define ZSTD_VERSION_RELEASE 0
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#define ZSTD_LIB_VERSION ZSTD_VERSION_MAJOR.ZSTD_VERSION_MINOR.ZSTD_VERSION_RELEASE
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#define ZSTD_QUOTE(str) #str
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@@ -73,61 +67,72 @@ ZSTDLIB_API unsigned ZSTD_versionNumber (void);
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/* *************************************
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* Simple functions
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* Simple API
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***************************************/
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/*! ZSTD_compress() :
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Compresses `srcSize` bytes from buffer `src` into buffer `dst` of size `dstCapacity`.
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Destination buffer must be already allocated.
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Compression runs faster if `dstCapacity` >= `ZSTD_compressBound(srcSize)`.
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@return : the number of bytes written into `dst`,
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Compresses `src` buffer into already allocated `dst`.
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Hint : compression runs faster if `dstCapacity` >= `ZSTD_compressBound(srcSize)`.
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@return : the number of bytes written into `dst` (<= `dstCapacity),
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or an error code if it fails (which can be tested using ZSTD_isError()) */
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ZSTDLIB_API size_t ZSTD_compress( void* dst, size_t dstCapacity,
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const void* src, size_t srcSize,
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int compressionLevel);
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ZSTDLIB_API size_t ZSTD_compress( void* dst, size_t dstCapacity,
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const void* src, size_t srcSize,
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int compressionLevel);
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/** ZSTD_getDecompressedSize() :
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* @return : decompressed size if known, 0 otherwise.
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note : to know precise reason why result is `0`, follow up with ZSTD_getFrameParams() */
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/*! ZSTD_getDecompressedSize() :
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* @return : decompressed size as a 64-bits value _if known_, 0 otherwise.
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* note 1 : decompressed size can be very large (64-bits value),
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* potentially larger than what local system can handle as a single memory segment.
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* In which case, it's necessary to use streaming mode to decompress data.
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* note 2 : decompressed size is an optional field, that may not be present.
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* When `return==0`, consider data to decompress could have any size.
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* In which case, it's necessary to use streaming mode to decompress data,
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* or rely on application's implied limits.
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* (For example, it may know that its own data is necessarily cut into blocks <= 16 KB).
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* note 3 : decompressed size could be wrong or intentionally modified !
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* Always ensure result fits within application's authorized limits !
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* Each application can have its own set of conditions.
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* If the intention is to decompress public data compressed by zstd command line utility,
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* it is recommended to support at least 8 MB for extended compatibility.
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* note 4 : when `return==0`, if precise failure cause is needed, use ZSTD_getFrameParams() to know more. */
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unsigned long long ZSTD_getDecompressedSize(const void* src, size_t srcSize);
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/*! ZSTD_decompress() :
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`compressedSize` : is the _exact_ size of compressed input, otherwise decompression will fail.
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`dstCapacity` must be equal or larger than originalSize.
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`compressedSize` : must be the _exact_ size of compressed input, otherwise decompression will fail.
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`dstCapacity` must be equal or larger than originalSize (see ZSTD_getDecompressedSize() ).
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If originalSize is unknown, and if there is no implied application-specific limitations,
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it's necessary to use streaming mode to decompress data.
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@return : the number of bytes decompressed into `dst` (<= `dstCapacity`),
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or an errorCode if it fails (which can be tested using ZSTD_isError()) */
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ZSTDLIB_API size_t ZSTD_decompress( void* dst, size_t dstCapacity,
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const void* src, size_t compressedSize);
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/* *************************************
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* Helper functions
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***************************************/
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ZSTDLIB_API size_t ZSTD_compressBound(size_t srcSize); /*!< maximum compressed size (worst case scenario) */
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/* Error Management */
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/*====== Helper functions ======*/
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ZSTDLIB_API int ZSTD_maxCLevel(void); /*!< maximum compression level available */
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ZSTDLIB_API size_t ZSTD_compressBound(size_t srcSize); /*!< maximum compressed size in worst case scenario */
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ZSTDLIB_API unsigned ZSTD_isError(size_t code); /*!< tells if a `size_t` function result is an error code */
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ZSTDLIB_API const char* ZSTD_getErrorName(size_t code); /*!< provides readable string for an error code */
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ZSTDLIB_API const char* ZSTD_getErrorName(size_t code); /*!< provides readable string from an error code */
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/* *************************************
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/*-*************************************
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* Explicit memory management
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***************************************/
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/** Compression context */
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typedef struct ZSTD_CCtx_s ZSTD_CCtx; /*< incomplete type */
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ZSTDLIB_API ZSTD_CCtx* ZSTD_createCCtx(void);
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ZSTDLIB_API size_t ZSTD_freeCCtx(ZSTD_CCtx* cctx); /*!< @return : errorCode */
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ZSTDLIB_API size_t ZSTD_freeCCtx(ZSTD_CCtx* cctx);
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/** ZSTD_compressCCtx() :
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Same as ZSTD_compress(), but requires an already allocated ZSTD_CCtx (see ZSTD_createCCtx()) */
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Same as ZSTD_compress(), requires an allocated ZSTD_CCtx (see ZSTD_createCCtx()) */
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ZSTDLIB_API size_t ZSTD_compressCCtx(ZSTD_CCtx* ctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize, int compressionLevel);
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/** Decompression context */
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typedef struct ZSTD_DCtx_s ZSTD_DCtx;
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typedef struct ZSTD_DCtx_s ZSTD_DCtx; /*< incomplete type */
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ZSTDLIB_API ZSTD_DCtx* ZSTD_createDCtx(void);
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ZSTDLIB_API size_t ZSTD_freeDCtx(ZSTD_DCtx* dctx); /*!< @return : errorCode */
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ZSTDLIB_API size_t ZSTD_freeDCtx(ZSTD_DCtx* dctx);
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/** ZSTD_decompressDCtx() :
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* Same as ZSTD_decompress(), but requires an already allocated ZSTD_DCtx (see ZSTD_createDCtx()) */
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* Same as ZSTD_decompress(), requires an allocated ZSTD_DCtx (see ZSTD_createDCtx()) */
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ZSTDLIB_API size_t ZSTD_decompressDCtx(ZSTD_DCtx* ctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize);
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@@ -135,10 +140,8 @@ ZSTDLIB_API size_t ZSTD_decompressDCtx(ZSTD_DCtx* ctx, void* dst, size_t dstCapa
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* Simple dictionary API
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***************************/
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/*! ZSTD_compress_usingDict() :
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* Compression using a pre-defined Dictionary content (see dictBuilder).
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* Note 1 : This function load the dictionary, resulting in a significant startup time.
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* Note 2 : `dict` must remain accessible and unmodified during compression operation.
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* Note 3 : `dict` can be `NULL`, in which case, it's equivalent to ZSTD_compressCCtx() */
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* Compression using a predefined Dictionary (see dictBuilder/zdict.h).
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* Note : This function load the dictionary, resulting in a significant startup time. */
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ZSTDLIB_API size_t ZSTD_compress_usingDict(ZSTD_CCtx* ctx,
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void* dst, size_t dstCapacity,
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const void* src, size_t srcSize,
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@@ -146,11 +149,9 @@ ZSTDLIB_API size_t ZSTD_compress_usingDict(ZSTD_CCtx* ctx,
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int compressionLevel);
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/*! ZSTD_decompress_usingDict() :
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* Decompression using a pre-defined Dictionary content (see dictBuilder).
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* Decompression using a predefined Dictionary (see dictBuilder/zdict.h).
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* Dictionary must be identical to the one used during compression.
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* Note 1 : This function load the dictionary, resulting in a significant startup time
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* Note 2 : `dict` must remain accessible and unmodified during compression operation.
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* Note 3 : `dict` can be `NULL`, in which case, it's equivalent to ZSTD_decompressDCtx() */
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* Note : This function load the dictionary, resulting in a significant startup time */
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ZSTDLIB_API size_t ZSTD_decompress_usingDict(ZSTD_DCtx* dctx,
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void* dst, size_t dstCapacity,
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const void* src, size_t srcSize,
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@@ -158,7 +159,7 @@ ZSTDLIB_API size_t ZSTD_decompress_usingDict(ZSTD_DCtx* dctx,
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/*-**************************
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* Advanced Dictionary API
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* Fast Dictionary API
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****************************/
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/*! ZSTD_createCDict() :
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* Create a digested dictionary, ready to start compression operation without startup delay.
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@@ -168,8 +169,8 @@ ZSTDLIB_API ZSTD_CDict* ZSTD_createCDict(const void* dict, size_t dictSize, int
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ZSTDLIB_API size_t ZSTD_freeCDict(ZSTD_CDict* CDict);
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/*! ZSTD_compress_usingCDict() :
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* Compression using a pre-digested Dictionary.
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* Much faster than ZSTD_compress_usingDict() when same dictionary is used multiple times.
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* Compression using a digested Dictionary.
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* Faster startup than ZSTD_compress_usingDict(), recommended when same dictionary is used multiple times.
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* Note that compression level is decided during dictionary creation */
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ZSTDLIB_API size_t ZSTD_compress_usingCDict(ZSTD_CCtx* cctx,
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void* dst, size_t dstCapacity,
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@@ -184,15 +185,14 @@ ZSTDLIB_API ZSTD_DDict* ZSTD_createDDict(const void* dict, size_t dictSize);
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ZSTDLIB_API size_t ZSTD_freeDDict(ZSTD_DDict* ddict);
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/*! ZSTD_decompress_usingDDict() :
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* Decompression using a pre-digested Dictionary
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* Much faster than ZSTD_decompress_usingDict() when same dictionary is used multiple times. */
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* Decompression using a digested Dictionary
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* Faster startup than ZSTD_decompress_usingDict(), recommended when same dictionary is used multiple times. */
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ZSTDLIB_API size_t ZSTD_decompress_usingDDict(ZSTD_DCtx* dctx,
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void* dst, size_t dstCapacity,
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const void* src, size_t srcSize,
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const ZSTD_DDict* ddict);
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#ifdef ZSTD_STATIC_LINKING_ONLY
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/* ====================================================================================
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@@ -203,7 +203,7 @@ ZSTDLIB_API size_t ZSTD_decompress_usingDDict(ZSTD_DCtx* dctx,
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* ==================================================================================== */
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/*--- Constants ---*/
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#define ZSTD_MAGICNUMBER 0xFD2FB527 /* v0.7 */
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#define ZSTD_MAGICNUMBER 0xFD2FB528 /* v0.8 */
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#define ZSTD_MAGIC_SKIPPABLE_START 0x184D2A50U
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#define ZSTD_WINDOWLOG_MAX_32 25
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@@ -215,7 +215,6 @@ ZSTDLIB_API size_t ZSTD_decompress_usingDDict(ZSTD_DCtx* dctx,
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#define ZSTD_HASHLOG_MAX ZSTD_WINDOWLOG_MAX
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#define ZSTD_HASHLOG_MIN 12
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#define ZSTD_HASHLOG3_MAX 17
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#define ZSTD_HASHLOG3_MIN 15
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#define ZSTD_SEARCHLOG_MAX (ZSTD_WINDOWLOG_MAX-1)
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#define ZSTD_SEARCHLOG_MIN 1
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#define ZSTD_SEARCHLENGTH_MAX 7
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@@ -265,7 +264,7 @@ typedef struct { ZSTD_allocFunction customAlloc; ZSTD_freeFunction customFree; v
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/*! ZSTD_estimateCCtxSize() :
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* Gives the amount of memory allocated for a ZSTD_CCtx given a set of compression parameters.
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* `frameContentSize` is an optional parameter, provide `0` if unknown */
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ZSTDLIB_API size_t ZSTD_estimateCCtxSize(ZSTD_compressionParameters cParams, unsigned long long frameContentSize);
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ZSTDLIB_API size_t ZSTD_estimateCCtxSize(ZSTD_compressionParameters cParams);
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/*! ZSTD_createCCtx_advanced() :
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* Create a ZSTD compression context using external alloc and free functions */
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@@ -280,8 +279,6 @@ ZSTDLIB_API ZSTD_CDict* ZSTD_createCDict_advanced(const void* dict, size_t dictS
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* Gives the amount of memory used by a given ZSTD_CCtx */
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ZSTDLIB_API size_t ZSTD_sizeofCCtx(const ZSTD_CCtx* cctx);
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ZSTDLIB_API unsigned ZSTD_maxCLevel (void);
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/*! ZSTD_getParams() :
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* same as ZSTD_getCParams(), but @return a full `ZSTD_parameters` object instead of a `ZSTD_compressionParameters`.
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* All fields of `ZSTD_frameParameters` are set to default (0) */
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@@ -326,15 +323,20 @@ ZSTDLIB_API size_t ZSTD_sizeofDCtx(const ZSTD_DCtx* dctx);
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/* ******************************************************************
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* Streaming functions (direct mode - synchronous and buffer-less)
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* Buffer-less streaming functions (synchronous mode)
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********************************************************************/
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/* This is an advanced API, giving full control over buffer management, for users which need direct control over memory.
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* But it's also a complex one, with a lot of restrictions (documented below).
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* For an easier streaming API, look into common/zbuff.h
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* which removes all restrictions by allocating and managing its own internal buffer */
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ZSTDLIB_API size_t ZSTD_compressBegin(ZSTD_CCtx* cctx, int compressionLevel);
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ZSTDLIB_API size_t ZSTD_compressBegin_usingDict(ZSTD_CCtx* cctx, const void* dict, size_t dictSize, int compressionLevel);
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ZSTDLIB_API size_t ZSTD_compressBegin_advanced(ZSTD_CCtx* cctx, const void* dict, size_t dictSize, ZSTD_parameters params, unsigned long long pledgedSrcSize);
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ZSTDLIB_API size_t ZSTD_copyCCtx(ZSTD_CCtx* cctx, const ZSTD_CCtx* preparedCCtx);
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ZSTDLIB_API size_t ZSTD_compressContinue(ZSTD_CCtx* cctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize);
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ZSTDLIB_API size_t ZSTD_compressEnd(ZSTD_CCtx* cctx, void* dst, size_t dstCapacity);
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ZSTDLIB_API size_t ZSTD_compressEnd(ZSTD_CCtx* cctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize);
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/*
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A ZSTD_CCtx object is required to track streaming operations.
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@@ -349,7 +351,7 @@ ZSTDLIB_API size_t ZSTD_compressEnd(ZSTD_CCtx* cctx, void* dst, size_t dstCapaci
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Then, consume your input using ZSTD_compressContinue().
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There are some important considerations to keep in mind when using this advanced function :
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- ZSTD_compressContinue() has no internal buffer. It uses externally provided buffer only.
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- Interface is synchronous : input is consumed entirely and produce 1 (or more) compressed blocks.
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- Interface is synchronous : input is consumed entirely and produce 1+ (or more) compressed blocks.
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- Caller must ensure there is enough space in `dst` to store compressed data under worst case scenario.
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Worst case evaluation is provided by ZSTD_compressBound().
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ZSTD_compressContinue() doesn't guarantee recover after a failed compression.
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@@ -358,9 +360,9 @@ ZSTDLIB_API size_t ZSTD_compressEnd(ZSTD_CCtx* cctx, void* dst, size_t dstCapaci
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- ZSTD_compressContinue() detects that prior input has been overwritten when `src` buffer overlaps.
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In which case, it will "discard" the relevant memory section from its history.
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Finish a frame with ZSTD_compressEnd(), which will write the epilogue.
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Without epilogue, frames will be considered unfinished (broken) by decoders.
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Finish a frame with ZSTD_compressEnd(), which will write the last block(s) and optional checksum.
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It's possible to use a NULL,0 src content, in which case, it will write a final empty block to end the frame,
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Without last block mark, frames will be considered unfinished (broken) by decoders.
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You can then reuse `ZSTD_CCtx` (ZSTD_compressBegin()) to compress some new frame.
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*/
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@@ -372,7 +374,7 @@ typedef struct {
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unsigned checksumFlag;
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} ZSTD_frameParams;
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ZSTDLIB_API size_t ZSTD_getFrameParams(ZSTD_frameParams* fparamsPtr, const void* src, size_t srcSize); /**< doesn't consume input */
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ZSTDLIB_API size_t ZSTD_getFrameParams(ZSTD_frameParams* fparamsPtr, const void* src, size_t srcSize); /**< doesn't consume input, see details below */
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ZSTDLIB_API size_t ZSTD_decompressBegin(ZSTD_DCtx* dctx);
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ZSTDLIB_API size_t ZSTD_decompressBegin_usingDict(ZSTD_DCtx* dctx, const void* dict, size_t dictSize);
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@@ -381,49 +383,58 @@ ZSTDLIB_API void ZSTD_copyDCtx(ZSTD_DCtx* dctx, const ZSTD_DCtx* preparedDCtx)
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ZSTDLIB_API size_t ZSTD_nextSrcSizeToDecompress(ZSTD_DCtx* dctx);
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ZSTDLIB_API size_t ZSTD_decompressContinue(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize);
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typedef enum { ZSTDnit_frameHeader, ZSTDnit_blockHeader, ZSTDnit_block, ZSTDnit_lastBlock, ZSTDnit_checksum, ZSTDnit_skippableFrame } ZSTD_nextInputType_e;
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ZSTDLIB_API ZSTD_nextInputType_e ZSTD_nextInputType(ZSTD_DCtx* dctx);
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/*
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Streaming decompression, direct mode (bufferless)
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Buffer-less streaming decompression (synchronous mode)
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A ZSTD_DCtx object is required to track streaming operations.
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Use ZSTD_createDCtx() / ZSTD_freeDCtx() to manage it.
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A ZSTD_DCtx object can be re-used multiple times.
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First optional operation is to retrieve frame parameters, using ZSTD_getFrameParams(), which doesn't consume the input.
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It can provide the minimum size of rolling buffer required to properly decompress data (`windowSize`),
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and optionally the final size of uncompressed content.
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(Note : content size is an optional info that may not be present. 0 means : content size unknown)
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Frame parameters are extracted from the beginning of compressed frame.
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The amount of data to read is variable, from ZSTD_frameHeaderSize_min to ZSTD_frameHeaderSize_max (so if `srcSize` >= ZSTD_frameHeaderSize_max, it will always work)
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If `srcSize` is too small for operation to succeed, function will return the minimum size it requires to produce a result.
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Result : 0 when successful, it means the ZSTD_frameParams structure has been filled.
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>0 : means there is not enough data into `src`. Provides the expected size to successfully decode header.
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errorCode, which can be tested using ZSTD_isError()
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First typical operation is to retrieve frame parameters, using ZSTD_getFrameParams().
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It fills a ZSTD_frameParams structure which provide important information to correctly decode the frame,
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such as the minimum rolling buffer size to allocate to decompress data (`windowSize`),
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and the dictionary ID used.
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(Note : content size is optional, it may not be present. 0 means : content size unknown).
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Note that these values could be wrong, either because of data malformation, or because an attacker is spoofing deliberate false information.
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As a consequence, check that values remain within valid application range, especially `windowSize`, before allocation.
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Each application can set its own limit, depending on local restrictions. For extended interoperability, it is recommended to support at least 8 MB.
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Frame parameters are extracted from the beginning of the compressed frame.
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Data fragment must be large enough to ensure successful decoding, typically `ZSTD_frameHeaderSize_max` bytes.
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@result : 0 : successful decoding, the `ZSTD_frameParams` structure is correctly filled.
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>0 : `srcSize` is too small, please provide at least @result bytes on next attempt.
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errorCode, which can be tested using ZSTD_isError().
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Start decompression, with ZSTD_decompressBegin() or ZSTD_decompressBegin_usingDict().
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Alternatively, you can copy a prepared context, using ZSTD_copyDCtx().
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Then use ZSTD_nextSrcSizeToDecompress() and ZSTD_decompressContinue() alternatively.
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ZSTD_nextSrcSizeToDecompress() tells how much bytes to provide as 'srcSize' to ZSTD_decompressContinue().
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ZSTD_decompressContinue() requires this exact amount of bytes, or it will fail.
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ZSTD_nextSrcSizeToDecompress() tells how many bytes to provide as 'srcSize' to ZSTD_decompressContinue().
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ZSTD_decompressContinue() requires this _exact_ amount of bytes, or it will fail.
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|
||||
@result of ZSTD_decompressContinue() is the number of bytes regenerated within 'dst' (necessarily <= dstCapacity).
|
||||
It can be zero, which is not an error; it just means ZSTD_decompressContinue() has decoded some header.
|
||||
It can be zero, which is not an error; it just means ZSTD_decompressContinue() has decoded some metadata item.
|
||||
It can also be an error code, which can be tested with ZSTD_isError().
|
||||
|
||||
ZSTD_decompressContinue() needs previous data blocks during decompression, up to `windowSize`.
|
||||
They should preferably be located contiguously, prior to current block.
|
||||
Alternatively, a round buffer of sufficient size is also possible. Sufficient size is determined by frame parameters.
|
||||
ZSTD_decompressContinue() is very sensitive to contiguity,
|
||||
if 2 blocks don't follow each other, make sure that either the compressor breaks contiguity at the same place,
|
||||
or that previous contiguous segment is large enough to properly handle maximum back-reference.
|
||||
or that previous contiguous segment is large enough to properly handle maximum back-reference.
|
||||
|
||||
A frame is fully decoded when ZSTD_nextSrcSizeToDecompress() returns zero.
|
||||
Context can then be reset to start a new decompression.
|
||||
|
||||
Note : it's possible to know if next input to present is a header or a block, using ZSTD_nextInputType().
|
||||
This information is not required to properly decode a frame.
|
||||
|
||||
== Special case : skippable frames ==
|
||||
|
||||
Skippable frames allow the integration of user-defined data into a flow of concatenated frames.
|
||||
Skippable frames will be ignored (skipped) by a decompressor. The format of skippable frame is following:
|
||||
Skippable frames allow integration of user-defined data into a flow of concatenated frames.
|
||||
Skippable frames will be ignored (skipped) by a decompressor. The format of skippable frames is as follows :
|
||||
a) Skippable frame ID - 4 Bytes, Little endian format, any value from 0x184D2A50 to 0x184D2A5F
|
||||
b) Frame Size - 4 Bytes, Little endian format, unsigned 32-bits
|
||||
c) Frame Content - any content (User Data) of length equal to Frame Size
|
||||
@@ -437,13 +448,10 @@ ZSTDLIB_API size_t ZSTD_decompressContinue(ZSTD_DCtx* dctx, void* dst, size_t ds
|
||||
* Block functions
|
||||
****************************************/
|
||||
/*! Block functions produce and decode raw zstd blocks, without frame metadata.
|
||||
Frame metadata cost is typically ~18 bytes, which is non-negligible on very small blocks.
|
||||
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.
|
||||
|
||||
A few rules to respect :
|
||||
- Uncompressed block size must be <= ZSTD_BLOCKSIZE_MAX (128 KB)
|
||||
+ If you need to compress more, cut data into multiple blocks
|
||||
+ Consider using the regular ZSTD_compress() instead, as frame metadata costs become negligible when source size is large.
|
||||
- Compressing and decompressing require a context structure
|
||||
+ Use ZSTD_createCCtx() and ZSTD_createDCtx()
|
||||
- It is necessary to init context before starting
|
||||
@@ -451,19 +459,22 @@ ZSTDLIB_API size_t ZSTD_decompressContinue(ZSTD_DCtx* dctx, void* dst, size_t ds
|
||||
+ decompression : ZSTD_decompressBegin()
|
||||
+ variants _usingDict() are also allowed
|
||||
+ copyCCtx() and copyDCtx() work too
|
||||
- Block size is limited, it must be <= ZSTD_getBlockSizeMax()
|
||||
+ If you need to compress more, cut data into multiple blocks
|
||||
+ Consider using the regular ZSTD_compress() instead, as frame metadata costs become negligible when source size is large.
|
||||
- When a block is considered not compressible enough, ZSTD_compressBlock() result will be zero.
|
||||
In which case, nothing is produced into `dst`.
|
||||
+ User must test for such outcome and deal directly with uncompressed data
|
||||
+ ZSTD_decompressBlock() doesn't accept uncompressed data as input !!!
|
||||
+ In case of multiple successive blocks, decoder must be informed of uncompressed block existence to follow proper history.
|
||||
Use ZSTD_insertBlock() in such a case.
|
||||
Insert block once it's copied into its final position.
|
||||
*/
|
||||
|
||||
#define ZSTD_BLOCKSIZE_MAX (128 * 1024) /* define, for static allocation */
|
||||
#define ZSTD_BLOCKSIZE_ABSOLUTEMAX (128 * 1024) /* define, for static allocation */
|
||||
ZSTDLIB_API size_t ZSTD_getBlockSizeMax(ZSTD_CCtx* cctx);
|
||||
ZSTDLIB_API size_t ZSTD_compressBlock (ZSTD_CCtx* cctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize);
|
||||
ZSTDLIB_API size_t ZSTD_decompressBlock(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize);
|
||||
ZSTDLIB_API size_t ZSTD_insertBlock(ZSTD_DCtx* dctx, const void* blockStart, size_t blockSize); /**< insert block into `dctx` history. Useful to track uncompressed blocks */
|
||||
ZSTDLIB_API size_t ZSTD_insertBlock(ZSTD_DCtx* dctx, const void* blockStart, size_t blockSize); /**< insert block into `dctx` history. Useful for uncompressed blocks */
|
||||
|
||||
|
||||
#endif /* ZSTD_STATIC_LINKING_ONLY */
|
||||
|
||||
Reference in New Issue
Block a user