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| author | Alexey Bykov <alexei4203@yandex.ru> | 2022-02-10 16:47:16 +0300 |
|---|---|---|
| committer | Daniil Cherednik <dcherednik@yandex-team.ru> | 2022-02-10 16:47:16 +0300 |
| commit | 4cadece7a57ab767e762a0bea1995a596aefeb11 (patch) | |
| tree | 7649c16cf4b52e994709f6c9e1716c993ca28759 /contrib/libs/zstd/lib/zstd.h | |
| parent | 143876304996506751ade0b80b3c47f188b9834f (diff) | |
| download | ydb-4cadece7a57ab767e762a0bea1995a596aefeb11.tar.gz | |
Restoring authorship annotation for Alexey Bykov <alexei4203@yandex.ru>. Commit 1 of 2.
Diffstat (limited to 'contrib/libs/zstd/lib/zstd.h')
| -rw-r--r-- | contrib/libs/zstd/lib/zstd.h | 2168 |
1 files changed, 1084 insertions, 1084 deletions
diff --git a/contrib/libs/zstd/lib/zstd.h b/contrib/libs/zstd/lib/zstd.h index a88ae7bf8e..b0585f8164 100644 --- a/contrib/libs/zstd/lib/zstd.h +++ b/contrib/libs/zstd/lib/zstd.h @@ -38,39 +38,39 @@ extern "C" { #endif -/******************************************************************************* +/******************************************************************************* Introduction - zstd, short for Zstandard, is a fast lossless compression algorithm, targeting - real-time compression scenarios at zlib-level and better compression ratios. - The zstd compression library provides in-memory compression and decompression - functions. - - The library supports regular compression levels from 1 up to ZSTD_maxCLevel(), - which is currently 22. Levels >= 20, labeled `--ultra`, should be used with - caution, as they require more memory. The library also offers negative - compression levels, which extend the range of speed vs. ratio preferences. - The lower the level, the faster the speed (at the cost of compression). - + zstd, short for Zstandard, is a fast lossless compression algorithm, targeting + real-time compression scenarios at zlib-level and better compression ratios. + The zstd compression library provides in-memory compression and decompression + functions. + + The library supports regular compression levels from 1 up to ZSTD_maxCLevel(), + which is currently 22. Levels >= 20, labeled `--ultra`, should be used with + caution, as they require more memory. The library also offers negative + compression levels, which extend the range of speed vs. ratio preferences. + The lower the level, the faster the speed (at the cost of compression). + Compression can be done in: - a single step (described as Simple API) - a single step, reusing a context (described as Explicit context) - unbounded multiple steps (described as Streaming compression) - - The compression ratio achievable on small data can be highly improved using - a dictionary. Dictionary compression can be performed in: + + The compression ratio achievable on small data can be highly improved using + a dictionary. Dictionary compression can be performed in: - a single step (described as Simple dictionary API) - - a single step, reusing a dictionary (described as Bulk-processing - dictionary API) + - a single step, reusing a dictionary (described as Bulk-processing + dictionary API) - Advanced experimental functions can be accessed using - `#define ZSTD_STATIC_LINKING_ONLY` before including zstd.h. - - Advanced experimental APIs should never be used with a dynamically-linked - library. They are not "stable"; their definitions or signatures may change in - the future. Only static linking is allowed. -*******************************************************************************/ + Advanced experimental functions can be accessed using + `#define ZSTD_STATIC_LINKING_ONLY` before including zstd.h. + Advanced experimental APIs should never be used with a dynamically-linked + library. They are not "stable"; their definitions or signatures may change in + the future. Only static linking is allowed. +*******************************************************************************/ + /*------ Version ------*/ #define ZSTD_VERSION_MAJOR 1 #define ZSTD_VERSION_MINOR 5 @@ -93,25 +93,25 @@ ZSTDLIB_API const char* ZSTD_versionString(void); /* ************************************* * Default constant ***************************************/ -#ifndef ZSTD_CLEVEL_DEFAULT -# define ZSTD_CLEVEL_DEFAULT 3 -#endif +#ifndef ZSTD_CLEVEL_DEFAULT +# define ZSTD_CLEVEL_DEFAULT 3 +#endif /* ************************************* * 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 */ -#define ZSTD_MAGIC_SKIPPABLE_MASK 0xFFFFFFF0 - -#define ZSTD_BLOCKSIZELOG_MAX 17 -#define ZSTD_BLOCKSIZE_MAX (1<<ZSTD_BLOCKSIZELOG_MAX) - - -/*************************************** + +/* 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 */ +#define ZSTD_MAGIC_SKIPPABLE_MASK 0xFFFFFFF0 + +#define ZSTD_BLOCKSIZELOG_MAX 17 +#define ZSTD_BLOCKSIZE_MAX (1<<ZSTD_BLOCKSIZELOG_MAX) + + +/*************************************** * Simple API ***************************************/ /*! ZSTD_compress() : @@ -132,11 +132,11 @@ ZSTDLIB_API size_t ZSTD_compress( void* dst, size_t dstCapacity, ZSTDLIB_API size_t ZSTD_decompress( void* dst, size_t dstCapacity, const void* src, size_t compressedSize); -/*! ZSTD_getFrameContentSize() : requires v1.3.0+ +/*! ZSTD_getFrameContentSize() : requires v1.3.0+ * `src` should point to the start of a ZSTD encoded frame. * `srcSize` must be at least as large as the frame header. * hint : any size >= `ZSTD_frameHeaderSize_max` is large enough. - * @return : - decompressed size of `src` frame content, if known + * @return : - decompressed size of `src` frame content, if known * - ZSTD_CONTENTSIZE_UNKNOWN if the size cannot be determined * - ZSTD_CONTENTSIZE_ERROR if an error occurred (e.g. invalid magic number, srcSize too small) * note 1 : a 0 return value means the frame is valid but "empty". @@ -146,8 +146,8 @@ ZSTDLIB_API size_t ZSTD_decompress( void* dst, size_t dstCapacity, * Optionally, application can rely on some implicit limit, * as ZSTD_decompress() only needs an upper bound of decompressed size. * (For example, data could be necessarily cut into blocks <= 16 KB). - * note 3 : decompressed size is always present when compression is completed using single-pass functions, - * such as ZSTD_compress(), ZSTD_compressCCtx() ZSTD_compress_usingDict() or ZSTD_compress_usingCDict(). + * note 3 : decompressed size is always present when compression is completed using single-pass functions, + * such as ZSTD_compress(), ZSTD_compressCCtx() ZSTD_compress_usingDict() or ZSTD_compress_usingCDict(). * note 4 : decompressed size can be very large (64-bits value), * potentially larger than what local system can handle as a single memory segment. * In which case, it's necessary to use streaming mode to decompress data. @@ -164,18 +164,18 @@ ZSTDLIB_API unsigned long long ZSTD_getFrameContentSize(const void *src, size_t * Both functions work the same way, but ZSTD_getDecompressedSize() blends * "empty", "unknown" and "error" results to the same return value (0), * while ZSTD_getFrameContentSize() gives them separate return values. - * @return : decompressed size of `src` frame content _if known and not empty_, 0 otherwise. */ + * @return : decompressed size of `src` frame content _if known and not empty_, 0 otherwise. */ ZSTDLIB_API unsigned long long ZSTD_getDecompressedSize(const void* src, size_t srcSize); /*! ZSTD_findFrameCompressedSize() : Requires v1.4.0+ - * `src` should point to the start of a ZSTD frame or skippable frame. - * `srcSize` must be >= first frame size - * @return : the compressed size of the first frame starting at `src`, - * suitable to pass as `srcSize` to `ZSTD_decompress` or similar, - * or an error code if input is invalid */ -ZSTDLIB_API size_t ZSTD_findFrameCompressedSize(const void* src, size_t srcSize); - - + * `src` should point to the start of a ZSTD frame or skippable frame. + * `srcSize` must be >= first frame size + * @return : the compressed size of the first frame starting at `src`, + * suitable to pass as `srcSize` to `ZSTD_decompress` or similar, + * or an error code if input is invalid */ +ZSTDLIB_API size_t ZSTD_findFrameCompressedSize(const void* src, size_t srcSize); + + /*====== Helper functions ======*/ #define ZSTD_COMPRESSBOUND(srcSize) ((srcSize) + ((srcSize)>>8) + (((srcSize) < (128<<10)) ? (((128<<10) - (srcSize)) >> 11) /* margin, from 64 to 0 */ : 0)) /* this formula ensures that bound(A) + bound(B) <= bound(A+B) as long as A and B >= 128 KB */ ZSTDLIB_API size_t ZSTD_compressBound(size_t srcSize); /*!< maximum compressed size in worst case single-pass scenario */ @@ -211,7 +211,7 @@ ZSTDLIB_API size_t ZSTD_freeCCtx(ZSTD_CCtx* cctx); /* accept NULL pointer * * If any advanced parameter was set using the advanced API, * they will all be reset. Only `compressionLevel` remains. */ -ZSTDLIB_API size_t ZSTD_compressCCtx(ZSTD_CCtx* cctx, +ZSTDLIB_API size_t ZSTD_compressCCtx(ZSTD_CCtx* cctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize, int compressionLevel); @@ -227,11 +227,11 @@ ZSTDLIB_API ZSTD_DCtx* ZSTD_createDCtx(void); ZSTDLIB_API size_t ZSTD_freeDCtx(ZSTD_DCtx* dctx); /* accept NULL pointer */ /*! ZSTD_decompressDCtx() : - * Same as ZSTD_decompress(), - * requires an allocated ZSTD_DCtx. - * Compatible with sticky parameters. - */ -ZSTDLIB_API size_t ZSTD_decompressDCtx(ZSTD_DCtx* dctx, + * Same as ZSTD_decompress(), + * requires an allocated ZSTD_DCtx. + * Compatible with sticky parameters. + */ +ZSTDLIB_API size_t ZSTD_decompressDCtx(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize); @@ -240,46 +240,46 @@ ZSTDLIB_API size_t ZSTD_decompressDCtx(ZSTD_DCtx* dctx, * Advanced compression API (Requires v1.4.0+) **********************************************/ -/* API design : - * Parameters are pushed one by one into an existing context, - * using ZSTD_CCtx_set*() functions. - * Pushed parameters are sticky : they are valid for next compressed frame, and any subsequent frame. - * "sticky" parameters are applicable to `ZSTD_compress2()` and `ZSTD_compressStream*()` ! +/* API design : + * Parameters are pushed one by one into an existing context, + * using ZSTD_CCtx_set*() functions. + * Pushed parameters are sticky : they are valid for next compressed frame, and any subsequent frame. + * "sticky" parameters are applicable to `ZSTD_compress2()` and `ZSTD_compressStream*()` ! * __They do not apply to "simple" one-shot variants such as ZSTD_compressCCtx()__ . - * - * It's possible to reset all parameters to "default" using ZSTD_CCtx_reset(). - * + * + * It's possible to reset all parameters to "default" using ZSTD_CCtx_reset(). + * * This API supersedes all other "advanced" API entry points in the experimental section. - * In the future, we expect to remove from experimental API entry points which are redundant with this API. - */ - - -/* Compression strategies, listed from fastest to strongest */ -typedef enum { ZSTD_fast=1, - ZSTD_dfast=2, - ZSTD_greedy=3, - ZSTD_lazy=4, - ZSTD_lazy2=5, - ZSTD_btlazy2=6, - ZSTD_btopt=7, - ZSTD_btultra=8, - ZSTD_btultra2=9 - /* note : new strategies _might_ be added in the future. - Only the order (from fast to strong) is guaranteed */ -} ZSTD_strategy; - -typedef enum { - - /* compression parameters - * Note: When compressing with a ZSTD_CDict these parameters are superseded + * In the future, we expect to remove from experimental API entry points which are redundant with this API. + */ + + +/* Compression strategies, listed from fastest to strongest */ +typedef enum { ZSTD_fast=1, + ZSTD_dfast=2, + ZSTD_greedy=3, + ZSTD_lazy=4, + ZSTD_lazy2=5, + ZSTD_btlazy2=6, + ZSTD_btopt=7, + ZSTD_btultra=8, + ZSTD_btultra2=9 + /* note : new strategies _might_ be added in the future. + Only the order (from fast to strong) is guaranteed */ +} ZSTD_strategy; + +typedef enum { + + /* compression parameters + * Note: When compressing with a ZSTD_CDict these parameters are superseded * by the parameters used to construct the ZSTD_CDict. * See ZSTD_CCtx_refCDict() for more info (superseded-by-cdict). */ ZSTD_c_compressionLevel=100, /* Set compression parameters according to pre-defined cLevel table. * Note that exact compression parameters are dynamically determined, * depending on both compression level and srcSize (when known). - * Default level is ZSTD_CLEVEL_DEFAULT==3. - * Special: value 0 means default, which is controlled by ZSTD_CLEVEL_DEFAULT. - * Note 1 : it's possible to pass a negative compression level. + * Default level is ZSTD_CLEVEL_DEFAULT==3. + * Special: value 0 means default, which is controlled by ZSTD_CLEVEL_DEFAULT. + * Note 1 : it's possible to pass a negative compression level. * Note 2 : setting a level does not automatically set all other compression parameters * to default. Setting this will however eventually dynamically impact the compression * parameters which have not been manually set. The manually set @@ -287,131 +287,131 @@ typedef enum { /* Advanced compression parameters : * It's possible to pin down compression parameters to some specific values. * In which case, these values are no longer dynamically selected by the compressor */ - ZSTD_c_windowLog=101, /* Maximum allowed back-reference distance, expressed as power of 2. + ZSTD_c_windowLog=101, /* Maximum allowed back-reference distance, expressed as power of 2. * This will set a memory budget for streaming decompression, * with larger values requiring more memory * and typically compressing more. - * Must be clamped between ZSTD_WINDOWLOG_MIN and ZSTD_WINDOWLOG_MAX. - * Special: value 0 means "use default windowLog". - * Note: Using a windowLog greater than ZSTD_WINDOWLOG_LIMIT_DEFAULT + * Must be clamped between ZSTD_WINDOWLOG_MIN and ZSTD_WINDOWLOG_MAX. + * Special: value 0 means "use default windowLog". + * Note: Using a windowLog greater than ZSTD_WINDOWLOG_LIMIT_DEFAULT * requires explicitly allowing such size at streaming decompression stage. */ - ZSTD_c_hashLog=102, /* Size of the initial probe table, as a power of 2. - * Resulting memory usage is (1 << (hashLog+2)). - * Must be clamped between ZSTD_HASHLOG_MIN and ZSTD_HASHLOG_MAX. - * Larger tables improve compression ratio of strategies <= dFast, - * and improve speed of strategies > dFast. - * Special: value 0 means "use default hashLog". */ - ZSTD_c_chainLog=103, /* Size of the multi-probe search table, as a power of 2. - * Resulting memory usage is (1 << (chainLog+2)). - * Must be clamped between ZSTD_CHAINLOG_MIN and ZSTD_CHAINLOG_MAX. - * Larger tables result in better and slower compression. + ZSTD_c_hashLog=102, /* Size of the initial probe table, as a power of 2. + * Resulting memory usage is (1 << (hashLog+2)). + * Must be clamped between ZSTD_HASHLOG_MIN and ZSTD_HASHLOG_MAX. + * Larger tables improve compression ratio of strategies <= dFast, + * and improve speed of strategies > dFast. + * Special: value 0 means "use default hashLog". */ + ZSTD_c_chainLog=103, /* Size of the multi-probe search table, as a power of 2. + * Resulting memory usage is (1 << (chainLog+2)). + * Must be clamped between ZSTD_CHAINLOG_MIN and ZSTD_CHAINLOG_MAX. + * Larger tables result in better and slower compression. * This parameter is useless for "fast" strategy. - * It's still useful when using "dfast" strategy, - * in which case it defines a secondary probe table. - * Special: value 0 means "use default chainLog". */ - ZSTD_c_searchLog=104, /* Number of search attempts, as a power of 2. - * More attempts result in better and slower compression. + * It's still useful when using "dfast" strategy, + * in which case it defines a secondary probe table. + * Special: value 0 means "use default chainLog". */ + ZSTD_c_searchLog=104, /* Number of search attempts, as a power of 2. + * More attempts result in better and slower compression. * This parameter is useless for "fast" and "dFast" strategies. - * Special: value 0 means "use default searchLog". */ - ZSTD_c_minMatch=105, /* Minimum size of searched matches. - * Note that Zstandard can still find matches of smaller size, - * it just tweaks its search algorithm to look for this size and larger. - * Larger values increase compression and decompression speed, but decrease ratio. - * Must be clamped between ZSTD_MINMATCH_MIN and ZSTD_MINMATCH_MAX. - * Note that currently, for all strategies < btopt, effective minimum is 4. - * , for all strategies > fast, effective maximum is 6. - * Special: value 0 means "use default minMatchLength". */ - ZSTD_c_targetLength=106, /* Impact of this field depends on strategy. - * For strategies btopt, btultra & btultra2: - * Length of Match considered "good enough" to stop search. - * Larger values make compression stronger, and slower. - * For strategy fast: - * Distance between match sampling. - * Larger values make compression faster, and weaker. - * Special: value 0 means "use default targetLength". */ - ZSTD_c_strategy=107, /* See ZSTD_strategy enum definition. - * The higher the value of selected strategy, the more complex it is, - * resulting in stronger and slower compression. - * Special: value 0 means "use default strategy". */ - /* LDM mode parameters */ - ZSTD_c_enableLongDistanceMatching=160, /* Enable long distance matching. - * This parameter is designed to improve compression ratio - * for large inputs, by finding large matches at long distance. - * It increases memory usage and window size. - * Note: enabling this parameter increases default ZSTD_c_windowLog to 128 MB + * Special: value 0 means "use default searchLog". */ + ZSTD_c_minMatch=105, /* Minimum size of searched matches. + * Note that Zstandard can still find matches of smaller size, + * it just tweaks its search algorithm to look for this size and larger. + * Larger values increase compression and decompression speed, but decrease ratio. + * Must be clamped between ZSTD_MINMATCH_MIN and ZSTD_MINMATCH_MAX. + * Note that currently, for all strategies < btopt, effective minimum is 4. + * , for all strategies > fast, effective maximum is 6. + * Special: value 0 means "use default minMatchLength". */ + ZSTD_c_targetLength=106, /* Impact of this field depends on strategy. + * For strategies btopt, btultra & btultra2: + * Length of Match considered "good enough" to stop search. + * Larger values make compression stronger, and slower. + * For strategy fast: + * Distance between match sampling. + * Larger values make compression faster, and weaker. + * Special: value 0 means "use default targetLength". */ + ZSTD_c_strategy=107, /* See ZSTD_strategy enum definition. + * The higher the value of selected strategy, the more complex it is, + * resulting in stronger and slower compression. + * Special: value 0 means "use default strategy". */ + /* LDM mode parameters */ + ZSTD_c_enableLongDistanceMatching=160, /* Enable long distance matching. + * This parameter is designed to improve compression ratio + * for large inputs, by finding large matches at long distance. + * It increases memory usage and window size. + * Note: enabling this parameter increases default ZSTD_c_windowLog to 128 MB * except when expressly set to a different value. * Note: will be enabled by default if ZSTD_c_windowLog >= 128 MB and * compression strategy >= ZSTD_btopt (== compression level 16+) */ - ZSTD_c_ldmHashLog=161, /* Size of the table for long distance matching, as a power of 2. - * Larger values increase memory usage and compression ratio, - * but decrease compression speed. - * Must be clamped between ZSTD_HASHLOG_MIN and ZSTD_HASHLOG_MAX - * default: windowlog - 7. - * Special: value 0 means "automatically determine hashlog". */ - ZSTD_c_ldmMinMatch=162, /* Minimum match size for long distance matcher. - * Larger/too small values usually decrease compression ratio. - * Must be clamped between ZSTD_LDM_MINMATCH_MIN and ZSTD_LDM_MINMATCH_MAX. - * Special: value 0 means "use default value" (default: 64). */ - ZSTD_c_ldmBucketSizeLog=163, /* Log size of each bucket in the LDM hash table for collision resolution. - * Larger values improve collision resolution but decrease compression speed. - * The maximum value is ZSTD_LDM_BUCKETSIZELOG_MAX. - * Special: value 0 means "use default value" (default: 3). */ - ZSTD_c_ldmHashRateLog=164, /* Frequency of inserting/looking up entries into the LDM hash table. - * Must be clamped between 0 and (ZSTD_WINDOWLOG_MAX - ZSTD_HASHLOG_MIN). - * Default is MAX(0, (windowLog - ldmHashLog)), optimizing hash table usage. - * Larger values improve compression speed. - * Deviating far from default value will likely result in a compression ratio decrease. - * Special: value 0 means "automatically determine hashRateLog". */ - - /* frame parameters */ - ZSTD_c_contentSizeFlag=200, /* Content size will be written into frame header _whenever known_ (default:1) - * Content size must be known at the beginning of compression. - * This is automatically the case when using ZSTD_compress2(), + ZSTD_c_ldmHashLog=161, /* Size of the table for long distance matching, as a power of 2. + * Larger values increase memory usage and compression ratio, + * but decrease compression speed. + * Must be clamped between ZSTD_HASHLOG_MIN and ZSTD_HASHLOG_MAX + * default: windowlog - 7. + * Special: value 0 means "automatically determine hashlog". */ + ZSTD_c_ldmMinMatch=162, /* Minimum match size for long distance matcher. + * Larger/too small values usually decrease compression ratio. + * Must be clamped between ZSTD_LDM_MINMATCH_MIN and ZSTD_LDM_MINMATCH_MAX. + * Special: value 0 means "use default value" (default: 64). */ + ZSTD_c_ldmBucketSizeLog=163, /* Log size of each bucket in the LDM hash table for collision resolution. + * Larger values improve collision resolution but decrease compression speed. + * The maximum value is ZSTD_LDM_BUCKETSIZELOG_MAX. + * Special: value 0 means "use default value" (default: 3). */ + ZSTD_c_ldmHashRateLog=164, /* Frequency of inserting/looking up entries into the LDM hash table. + * Must be clamped between 0 and (ZSTD_WINDOWLOG_MAX - ZSTD_HASHLOG_MIN). + * Default is MAX(0, (windowLog - ldmHashLog)), optimizing hash table usage. + * Larger values improve compression speed. + * Deviating far from default value will likely result in a compression ratio decrease. + * Special: value 0 means "automatically determine hashRateLog". */ + + /* frame parameters */ + ZSTD_c_contentSizeFlag=200, /* Content size will be written into frame header _whenever known_ (default:1) + * Content size must be known at the beginning of compression. + * This is automatically the case when using ZSTD_compress2(), * For streaming scenarios, content size must be provided with ZSTD_CCtx_setPledgedSrcSize() */ - ZSTD_c_checksumFlag=201, /* A 32-bits checksum of content is written at end of frame (default:0) */ - ZSTD_c_dictIDFlag=202, /* When applicable, dictionary's ID is written into frame header (default:1) */ + ZSTD_c_checksumFlag=201, /* A 32-bits checksum of content is written at end of frame (default:0) */ + ZSTD_c_dictIDFlag=202, /* When applicable, dictionary's ID is written into frame header (default:1) */ - /* multi-threading parameters */ + /* multi-threading parameters */ /* These parameters are only active if multi-threading is enabled (compiled with build macro ZSTD_MULTITHREAD). * Otherwise, trying to set any other value than default (0) will be a no-op and return an error. * In a situation where it's unknown if the linked library supports multi-threading or not, * setting ZSTD_c_nbWorkers to any value >= 1 and consulting the return value provides a quick way to check this property. */ - ZSTD_c_nbWorkers=400, /* Select how many threads will be spawned to compress in parallel. + ZSTD_c_nbWorkers=400, /* Select how many threads will be spawned to compress in parallel. * When nbWorkers >= 1, triggers asynchronous mode when invoking ZSTD_compressStream*() : - * ZSTD_compressStream*() consumes input and flush output if possible, but immediately gives back control to caller, + * ZSTD_compressStream*() consumes input and flush output if possible, but immediately gives back control to caller, * while compression is performed in parallel, within worker thread(s). - * (note : a strong exception to this rule is when first invocation of ZSTD_compressStream2() sets ZSTD_e_end : - * in which case, ZSTD_compressStream2() delegates to ZSTD_compress2(), which is always a blocking call). - * More workers improve speed, but also increase memory usage. + * (note : a strong exception to this rule is when first invocation of ZSTD_compressStream2() sets ZSTD_e_end : + * in which case, ZSTD_compressStream2() delegates to ZSTD_compress2(), which is always a blocking call). + * More workers improve speed, but also increase memory usage. * Default value is `0`, aka "single-threaded mode" : no worker is spawned, * compression is performed inside Caller's thread, and all invocations are blocking */ - ZSTD_c_jobSize=401, /* Size of a compression job. This value is enforced only when nbWorkers >= 1. - * Each compression job is completed in parallel, so this value can indirectly impact the nb of active threads. - * 0 means default, which is dynamically determined based on compression parameters. + ZSTD_c_jobSize=401, /* Size of a compression job. This value is enforced only when nbWorkers >= 1. + * Each compression job is completed in parallel, so this value can indirectly impact the nb of active threads. + * 0 means default, which is dynamically determined based on compression parameters. * Job size must be a minimum of overlap size, or ZSTDMT_JOBSIZE_MIN (= 512 KB), whichever is largest. * The minimum size is automatically and transparently enforced. */ - ZSTD_c_overlapLog=402, /* Control the overlap size, as a fraction of window size. - * The overlap size is an amount of data reloaded from previous job at the beginning of a new job. - * It helps preserve compression ratio, while each job is compressed in parallel. - * This value is enforced only when nbWorkers >= 1. - * Larger values increase compression ratio, but decrease speed. - * Possible values range from 0 to 9 : - * - 0 means "default" : value will be determined by the library, depending on strategy - * - 1 means "no overlap" - * - 9 means "full overlap", using a full window size. - * Each intermediate rank increases/decreases load size by a factor 2 : - * 9: full window; 8: w/2; 7: w/4; 6: w/8; 5:w/16; 4: w/32; 3:w/64; 2:w/128; 1:no overlap; 0:default - * default value varies between 6 and 9, depending on strategy */ - - /* note : additional experimental parameters are also available - * within the experimental section of the API. - * At the time of this writing, they include : - * ZSTD_c_rsyncable - * ZSTD_c_format - * ZSTD_c_forceMaxWindow - * ZSTD_c_forceAttachDict - * ZSTD_c_literalCompressionMode + ZSTD_c_overlapLog=402, /* Control the overlap size, as a fraction of window size. + * The overlap size is an amount of data reloaded from previous job at the beginning of a new job. + * It helps preserve compression ratio, while each job is compressed in parallel. + * This value is enforced only when nbWorkers >= 1. + * Larger values increase compression ratio, but decrease speed. + * Possible values range from 0 to 9 : + * - 0 means "default" : value will be determined by the library, depending on strategy + * - 1 means "no overlap" + * - 9 means "full overlap", using a full window size. + * Each intermediate rank increases/decreases load size by a factor 2 : + * 9: full window; 8: w/2; 7: w/4; 6: w/8; 5:w/16; 4: w/32; 3:w/64; 2:w/128; 1:no overlap; 0:default + * default value varies between 6 and 9, depending on strategy */ + + /* note : additional experimental parameters are also available + * within the experimental section of the API. + * At the time of this writing, they include : + * ZSTD_c_rsyncable + * ZSTD_c_format + * ZSTD_c_forceMaxWindow + * ZSTD_c_forceAttachDict + * ZSTD_c_literalCompressionMode * ZSTD_c_targetCBlockSize * ZSTD_c_srcSizeHint * ZSTD_c_enableDedicatedDictSearch @@ -421,15 +421,15 @@ typedef enum { * ZSTD_c_validateSequences * ZSTD_c_useBlockSplitter * ZSTD_c_useRowMatchFinder - * 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, + * 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_c_experimentalParam7=1004, ZSTD_c_experimentalParam8=1005, @@ -440,155 +440,155 @@ typedef enum { ZSTD_c_experimentalParam13=1010, ZSTD_c_experimentalParam14=1011, ZSTD_c_experimentalParam15=1012 -} ZSTD_cParameter; - -typedef struct { - size_t error; - int lowerBound; - int upperBound; -} ZSTD_bounds; - -/*! ZSTD_cParam_getBounds() : - * All parameters must belong to an interval with lower and upper bounds, - * otherwise they will either trigger an error or be automatically clamped. - * @return : a structure, ZSTD_bounds, which contains - * - an error status field, which must be tested using ZSTD_isError() - * - lower and upper bounds, both inclusive - */ -ZSTDLIB_API ZSTD_bounds ZSTD_cParam_getBounds(ZSTD_cParameter cParam); - -/*! ZSTD_CCtx_setParameter() : - * Set one compression parameter, selected by enum ZSTD_cParameter. - * All parameters have valid bounds. Bounds can be queried using ZSTD_cParam_getBounds(). - * Providing a value beyond bound will either clamp it, or trigger an error (depending on parameter). - * Setting a parameter is generally only possible during frame initialization (before starting compression). - * Exception : when using multi-threading mode (nbWorkers >= 1), - * the following parameters can be updated _during_ compression (within same frame): - * => compressionLevel, hashLog, chainLog, searchLog, minMatch, targetLength and strategy. - * new parameters will be active for next job only (after a flush()). - * @return : an error code (which can be tested using ZSTD_isError()). - */ -ZSTDLIB_API size_t ZSTD_CCtx_setParameter(ZSTD_CCtx* cctx, ZSTD_cParameter param, int value); - -/*! ZSTD_CCtx_setPledgedSrcSize() : - * Total input data size to be compressed as a single frame. - * Value will be written in frame header, unless if explicitly forbidden using ZSTD_c_contentSizeFlag. - * This value will also be controlled at end of frame, and trigger an error if not respected. - * @result : 0, or an error code (which can be tested with ZSTD_isError()). - * Note 1 : pledgedSrcSize==0 actually means zero, aka an empty frame. - * In order to mean "unknown content size", pass constant ZSTD_CONTENTSIZE_UNKNOWN. - * ZSTD_CONTENTSIZE_UNKNOWN is default value for any new frame. - * Note 2 : pledgedSrcSize is only valid once, for the next frame. - * It's discarded at the end of the frame, and replaced by ZSTD_CONTENTSIZE_UNKNOWN. - * Note 3 : Whenever all input data is provided and consumed in a single round, - * for example with ZSTD_compress2(), - * or invoking immediately ZSTD_compressStream2(,,,ZSTD_e_end), - * this value is automatically overridden by srcSize instead. - */ -ZSTDLIB_API size_t ZSTD_CCtx_setPledgedSrcSize(ZSTD_CCtx* cctx, unsigned long long pledgedSrcSize); - -typedef enum { - ZSTD_reset_session_only = 1, - ZSTD_reset_parameters = 2, - ZSTD_reset_session_and_parameters = 3 -} ZSTD_ResetDirective; - -/*! ZSTD_CCtx_reset() : - * There are 2 different things that can be reset, independently or jointly : - * - The session : will stop compressing current frame, and make CCtx ready to start a new one. - * Useful after an error, or to interrupt any ongoing compression. - * Any internal data not yet flushed is cancelled. - * Compression parameters and dictionary remain unchanged. - * They will be used to compress next frame. - * Resetting session never fails. - * - The parameters : changes all parameters back to "default". - * This removes any reference to any dictionary too. - * Parameters can only be changed between 2 sessions (i.e. no compression is currently ongoing) - * otherwise the reset fails, and function returns an error value (which can be tested using ZSTD_isError()) - * - Both : similar to resetting the session, followed by resetting parameters. - */ -ZSTDLIB_API size_t ZSTD_CCtx_reset(ZSTD_CCtx* cctx, ZSTD_ResetDirective reset); - -/*! ZSTD_compress2() : - * Behave the same as ZSTD_compressCCtx(), but compression parameters are set using the advanced API. - * ZSTD_compress2() always starts a new frame. - * Should cctx hold data from a previously unfinished frame, everything about it is forgotten. - * - Compression parameters are pushed into CCtx before starting compression, using ZSTD_CCtx_set*() - * - The function is always blocking, returns when compression is completed. - * Hint : compression runs faster if `dstCapacity` >= `ZSTD_compressBound(srcSize)`. - * @return : compressed size written into `dst` (<= `dstCapacity), - * or an error code if it fails (which can be tested using ZSTD_isError()). - */ -ZSTDLIB_API size_t ZSTD_compress2( ZSTD_CCtx* cctx, - void* dst, size_t dstCapacity, - const void* src, size_t srcSize); - - +} ZSTD_cParameter; + +typedef struct { + size_t error; + int lowerBound; + int upperBound; +} ZSTD_bounds; + +/*! ZSTD_cParam_getBounds() : + * All parameters must belong to an interval with lower and upper bounds, + * otherwise they will either trigger an error or be automatically clamped. + * @return : a structure, ZSTD_bounds, which contains + * - an error status field, which must be tested using ZSTD_isError() + * - lower and upper bounds, both inclusive + */ +ZSTDLIB_API ZSTD_bounds ZSTD_cParam_getBounds(ZSTD_cParameter cParam); + +/*! ZSTD_CCtx_setParameter() : + * Set one compression parameter, selected by enum ZSTD_cParameter. + * All parameters have valid bounds. Bounds can be queried using ZSTD_cParam_getBounds(). + * Providing a value beyond bound will either clamp it, or trigger an error (depending on parameter). + * Setting a parameter is generally only possible during frame initialization (before starting compression). + * Exception : when using multi-threading mode (nbWorkers >= 1), + * the following parameters can be updated _during_ compression (within same frame): + * => compressionLevel, hashLog, chainLog, searchLog, minMatch, targetLength and strategy. + * new parameters will be active for next job only (after a flush()). + * @return : an error code (which can be tested using ZSTD_isError()). + */ +ZSTDLIB_API size_t ZSTD_CCtx_setParameter(ZSTD_CCtx* cctx, ZSTD_cParameter param, int value); + +/*! ZSTD_CCtx_setPledgedSrcSize() : + * Total input data size to be compressed as a single frame. + * Value will be written in frame header, unless if explicitly forbidden using ZSTD_c_contentSizeFlag. + * This value will also be controlled at end of frame, and trigger an error if not respected. + * @result : 0, or an error code (which can be tested with ZSTD_isError()). + * Note 1 : pledgedSrcSize==0 actually means zero, aka an empty frame. + * In order to mean "unknown content size", pass constant ZSTD_CONTENTSIZE_UNKNOWN. + * ZSTD_CONTENTSIZE_UNKNOWN is default value for any new frame. + * Note 2 : pledgedSrcSize is only valid once, for the next frame. + * It's discarded at the end of the frame, and replaced by ZSTD_CONTENTSIZE_UNKNOWN. + * Note 3 : Whenever all input data is provided and consumed in a single round, + * for example with ZSTD_compress2(), + * or invoking immediately ZSTD_compressStream2(,,,ZSTD_e_end), + * this value is automatically overridden by srcSize instead. + */ +ZSTDLIB_API size_t ZSTD_CCtx_setPledgedSrcSize(ZSTD_CCtx* cctx, unsigned long long pledgedSrcSize); + +typedef enum { + ZSTD_reset_session_only = 1, + ZSTD_reset_parameters = 2, + ZSTD_reset_session_and_parameters = 3 +} ZSTD_ResetDirective; + +/*! ZSTD_CCtx_reset() : + * There are 2 different things that can be reset, independently or jointly : + * - The session : will stop compressing current frame, and make CCtx ready to start a new one. + * Useful after an error, or to interrupt any ongoing compression. + * Any internal data not yet flushed is cancelled. + * Compression parameters and dictionary remain unchanged. + * They will be used to compress next frame. + * Resetting session never fails. + * - The parameters : changes all parameters back to "default". + * This removes any reference to any dictionary too. + * Parameters can only be changed between 2 sessions (i.e. no compression is currently ongoing) + * otherwise the reset fails, and function returns an error value (which can be tested using ZSTD_isError()) + * - Both : similar to resetting the session, followed by resetting parameters. + */ +ZSTDLIB_API size_t ZSTD_CCtx_reset(ZSTD_CCtx* cctx, ZSTD_ResetDirective reset); + +/*! ZSTD_compress2() : + * Behave the same as ZSTD_compressCCtx(), but compression parameters are set using the advanced API. + * ZSTD_compress2() always starts a new frame. + * Should cctx hold data from a previously unfinished frame, everything about it is forgotten. + * - Compression parameters are pushed into CCtx before starting compression, using ZSTD_CCtx_set*() + * - The function is always blocking, returns when compression is completed. + * Hint : compression runs faster if `dstCapacity` >= `ZSTD_compressBound(srcSize)`. + * @return : compressed size written into `dst` (<= `dstCapacity), + * or an error code if it fails (which can be tested using ZSTD_isError()). + */ +ZSTDLIB_API size_t ZSTD_compress2( ZSTD_CCtx* cctx, + void* dst, size_t dstCapacity, + const void* src, size_t srcSize); + + /*********************************************** * Advanced decompression API (Requires v1.4.0+) ************************************************/ - -/* The advanced API pushes parameters one by one into an existing DCtx context. - * Parameters are sticky, and remain valid for all following frames - * using the same DCtx context. - * It's possible to reset parameters to default values using ZSTD_DCtx_reset(). - * Note : This API is compatible with existing ZSTD_decompressDCtx() and ZSTD_decompressStream(). - * Therefore, no new decompression function is necessary. - */ - -typedef enum { - - ZSTD_d_windowLogMax=100, /* Select a size limit (in power of 2) beyond which - * the streaming API will refuse to allocate memory buffer - * in order to protect the host from unreasonable memory requirements. - * This parameter is only useful in streaming mode, since no internal buffer is allocated in single-pass mode. - * By default, a decompression context accepts window sizes <= (1 << ZSTD_WINDOWLOG_LIMIT_DEFAULT). - * Special: value 0 means "use default maximum windowLog". */ - - /* note : additional experimental parameters are also available - * within the experimental section of the API. - * At the time of this writing, they include : + +/* The advanced API pushes parameters one by one into an existing DCtx context. + * Parameters are sticky, and remain valid for all following frames + * using the same DCtx context. + * It's possible to reset parameters to default values using ZSTD_DCtx_reset(). + * Note : This API is compatible with existing ZSTD_decompressDCtx() and ZSTD_decompressStream(). + * Therefore, no new decompression function is necessary. + */ + +typedef enum { + + ZSTD_d_windowLogMax=100, /* Select a size limit (in power of 2) beyond which + * the streaming API will refuse to allocate memory buffer + * in order to protect the host from unreasonable memory requirements. + * This parameter is only useful in streaming mode, since no internal buffer is allocated in single-pass mode. + * By default, a decompression context accepts window sizes <= (1 << ZSTD_WINDOWLOG_LIMIT_DEFAULT). + * Special: value 0 means "use default maximum windowLog". */ + + /* note : additional experimental parameters are also available + * within the experimental section of the API. + * At the time of this writing, they include : * ZSTD_d_format * ZSTD_d_stableOutBuffer * ZSTD_d_forceIgnoreChecksum * ZSTD_d_refMultipleDDicts - * Because they are not stable, it's necessary to define ZSTD_STATIC_LINKING_ONLY to access them. - * note : never ever use experimentalParam? names directly - */ + * Because they are not stable, it's necessary to define ZSTD_STATIC_LINKING_ONLY to access them. + * note : never ever use experimentalParam? names directly + */ ZSTD_d_experimentalParam1=1000, ZSTD_d_experimentalParam2=1001, ZSTD_d_experimentalParam3=1002, ZSTD_d_experimentalParam4=1003 - -} ZSTD_dParameter; - -/*! ZSTD_dParam_getBounds() : - * All parameters must belong to an interval with lower and upper bounds, - * otherwise they will either trigger an error or be automatically clamped. - * @return : a structure, ZSTD_bounds, which contains - * - an error status field, which must be tested using ZSTD_isError() - * - both lower and upper bounds, inclusive - */ -ZSTDLIB_API ZSTD_bounds ZSTD_dParam_getBounds(ZSTD_dParameter dParam); - -/*! ZSTD_DCtx_setParameter() : - * Set one compression parameter, selected by enum ZSTD_dParameter. - * All parameters have valid bounds. Bounds can be queried using ZSTD_dParam_getBounds(). - * Providing a value beyond bound will either clamp it, or trigger an error (depending on parameter). - * Setting a parameter is only possible during frame initialization (before starting decompression). - * @return : 0, or an error code (which can be tested using ZSTD_isError()). - */ -ZSTDLIB_API size_t ZSTD_DCtx_setParameter(ZSTD_DCtx* dctx, ZSTD_dParameter param, int value); - -/*! ZSTD_DCtx_reset() : - * Return a DCtx to clean state. - * Session and parameters can be reset jointly or separately. - * Parameters can only be reset when no active frame is being decompressed. - * @return : 0, or an error code, which can be tested with ZSTD_isError() - */ -ZSTDLIB_API size_t ZSTD_DCtx_reset(ZSTD_DCtx* dctx, ZSTD_ResetDirective reset); - - + +} ZSTD_dParameter; + +/*! ZSTD_dParam_getBounds() : + * All parameters must belong to an interval with lower and upper bounds, + * otherwise they will either trigger an error or be automatically clamped. + * @return : a structure, ZSTD_bounds, which contains + * - an error status field, which must be tested using ZSTD_isError() + * - both lower and upper bounds, inclusive + */ +ZSTDLIB_API ZSTD_bounds ZSTD_dParam_getBounds(ZSTD_dParameter dParam); + +/*! ZSTD_DCtx_setParameter() : + * Set one compression parameter, selected by enum ZSTD_dParameter. + * All parameters have valid bounds. Bounds can be queried using ZSTD_dParam_getBounds(). + * Providing a value beyond bound will either clamp it, or trigger an error (depending on parameter). + * Setting a parameter is only possible during frame initialization (before starting decompression). + * @return : 0, or an error code (which can be tested using ZSTD_isError()). + */ +ZSTDLIB_API size_t ZSTD_DCtx_setParameter(ZSTD_DCtx* dctx, ZSTD_dParameter param, int value); + +/*! ZSTD_DCtx_reset() : + * Return a DCtx to clean state. + * Session and parameters can be reset jointly or separately. + * Parameters can only be reset when no active frame is being decompressed. + * @return : 0, or an error code, which can be tested with ZSTD_isError() + */ +ZSTDLIB_API size_t ZSTD_DCtx_reset(ZSTD_DCtx* dctx, ZSTD_ResetDirective reset); + + /**************************** * Streaming ****************************/ @@ -613,108 +613,108 @@ typedef struct ZSTD_outBuffer_s { * A ZSTD_CStream object is required to track streaming operation. * Use ZSTD_createCStream() and ZSTD_freeCStream() to create/release resources. * ZSTD_CStream objects can be reused multiple times on consecutive compression operations. -* It is recommended to re-use ZSTD_CStream since it will play nicer with system's memory, by re-using already allocated memory. -* -* For parallel execution, use one separate ZSTD_CStream per thread. +* It is recommended to re-use ZSTD_CStream since it will play nicer with system's memory, by re-using already allocated memory. * -* note : since v1.3.0, ZSTD_CStream and ZSTD_CCtx are the same thing. +* For parallel execution, use one separate ZSTD_CStream per thread. * -* Parameters are sticky : when starting a new compression on the same context, -* it will re-use the same sticky parameters as previous compression session. -* When in doubt, it's recommended to fully initialize the context before usage. -* Use ZSTD_CCtx_reset() to reset the context and ZSTD_CCtx_setParameter(), -* ZSTD_CCtx_setPledgedSrcSize(), or ZSTD_CCtx_loadDictionary() and friends to -* set more specific parameters, the pledged source size, or load a dictionary. +* note : since v1.3.0, ZSTD_CStream and ZSTD_CCtx are the same thing. * -* Use ZSTD_compressStream2() with ZSTD_e_continue as many times as necessary to -* consume input stream. The function will automatically update both `pos` -* fields within `input` and `output`. -* Note that the function may not consume the entire input, for example, because -* the output buffer is already full, in which case `input.pos < input.size`. -* The caller must check if input has been entirely consumed. -* If not, the caller must make some room to receive more compressed data, -* and then present again remaining input data. -* note: ZSTD_e_continue is guaranteed to make some forward progress when called, -* but doesn't guarantee maximal forward progress. This is especially relevant -* when compressing with multiple threads. The call won't block if it can -* consume some input, but if it can't it will wait for some, but not all, -* output to be flushed. -* @return : provides a minimum amount of data remaining to be flushed from internal buffers -* or an error code, which can be tested using ZSTD_isError(). -* -* At any moment, it's possible to flush whatever data might remain stuck within internal buffer, -* using ZSTD_compressStream2() with ZSTD_e_flush. `output->pos` will be updated. -* Note that, if `output->size` is too small, a single invocation with ZSTD_e_flush might not be enough (return code > 0). -* In which case, make some room to receive more compressed data, and call again ZSTD_compressStream2() with ZSTD_e_flush. -* You must continue calling ZSTD_compressStream2() with ZSTD_e_flush until it returns 0, at which point you can change the -* operation. -* note: ZSTD_e_flush will flush as much output as possible, meaning when compressing with multiple threads, it will -* block until the flush is complete or the output buffer is full. -* @return : 0 if internal buffers are entirely flushed, -* >0 if some data still present within internal buffer (the value is minimal estimation of remaining size), +* Parameters are sticky : when starting a new compression on the same context, +* it will re-use the same sticky parameters as previous compression session. +* When in doubt, it's recommended to fully initialize the context before usage. +* Use ZSTD_CCtx_reset() to reset the context and ZSTD_CCtx_setParameter(), +* ZSTD_CCtx_setPledgedSrcSize(), or ZSTD_CCtx_loadDictionary() and friends to +* set more specific parameters, the pledged source size, or load a dictionary. +* +* Use ZSTD_compressStream2() with ZSTD_e_continue as many times as necessary to +* consume input stream. The function will automatically update both `pos` +* fields within `input` and `output`. +* Note that the function may not consume the entire input, for example, because +* the output buffer is already full, in which case `input.pos < input.size`. +* The caller must check if input has been entirely consumed. +* If not, the caller must make some room to receive more compressed data, +* and then present again remaining input data. +* note: ZSTD_e_continue is guaranteed to make some forward progress when called, +* but doesn't guarantee maximal forward progress. This is especially relevant +* when compressing with multiple threads. The call won't block if it can +* consume some input, but if it can't it will wait for some, but not all, +* output to be flushed. +* @return : provides a minimum amount of data remaining to be flushed from internal buffers +* or an error code, which can be tested using ZSTD_isError(). +* +* At any moment, it's possible to flush whatever data might remain stuck within internal buffer, +* using ZSTD_compressStream2() with ZSTD_e_flush. `output->pos` will be updated. +* Note that, if `output->size` is too small, a single invocation with ZSTD_e_flush might not be enough (return code > 0). +* In which case, make some room to receive more compressed data, and call again ZSTD_compressStream2() with ZSTD_e_flush. +* You must continue calling ZSTD_compressStream2() with ZSTD_e_flush until it returns 0, at which point you can change the +* operation. +* note: ZSTD_e_flush will flush as much output as possible, meaning when compressing with multiple threads, it will +* block until the flush is complete or the output buffer is full. +* @return : 0 if internal buffers are entirely flushed, +* >0 if some data still present within internal buffer (the value is minimal estimation of remaining size), * or an error code, which can be tested using ZSTD_isError(). * -* Calling ZSTD_compressStream2() with ZSTD_e_end instructs to finish a frame. +* Calling ZSTD_compressStream2() with ZSTD_e_end instructs to finish a frame. * It will perform a flush and write frame epilogue. * The epilogue is required for decoders to consider a frame completed. -* flush operation is the same, and follows same rules as calling ZSTD_compressStream2() with ZSTD_e_flush. -* You must continue calling ZSTD_compressStream2() with ZSTD_e_end until it returns 0, at which point you are free to -* start a new frame. -* note: ZSTD_e_end will flush as much output as possible, meaning when compressing with multiple threads, it will -* block until the flush is complete or the output buffer is full. +* flush operation is the same, and follows same rules as calling ZSTD_compressStream2() with ZSTD_e_flush. +* You must continue calling ZSTD_compressStream2() with ZSTD_e_end until it returns 0, at which point you are free to +* start a new frame. +* note: ZSTD_e_end will flush as much output as possible, meaning when compressing with multiple threads, it will +* block until the flush is complete or the output buffer is full. * @return : 0 if frame fully completed and fully flushed, -* >0 if some data still present within internal buffer (the value is minimal estimation of remaining size), +* >0 if some data still present within internal buffer (the value is minimal estimation of remaining size), * or an error code, which can be tested using ZSTD_isError(). * * *******************************************************************/ typedef ZSTD_CCtx ZSTD_CStream; /**< CCtx and CStream are now effectively same object (>= v1.3.0) */ - /* Continue to distinguish them for compatibility with older versions <= v1.2.0 */ + /* Continue to distinguish them for compatibility with older versions <= v1.2.0 */ /*===== ZSTD_CStream management functions =====*/ ZSTDLIB_API ZSTD_CStream* ZSTD_createCStream(void); ZSTDLIB_API size_t ZSTD_freeCStream(ZSTD_CStream* zcs); /* accept NULL pointer */ /*===== Streaming compression functions =====*/ -typedef enum { - ZSTD_e_continue=0, /* collect more data, encoder decides when to output compressed result, for optimal compression ratio */ - ZSTD_e_flush=1, /* flush any data provided so far, - * it creates (at least) one new block, that can be decoded immediately on reception; - * frame will continue: any future data can still reference previously compressed data, improving compression. - * note : multithreaded compression will block to flush as much output as possible. */ - ZSTD_e_end=2 /* flush any remaining data _and_ close current frame. - * note that frame is only closed after compressed data is fully flushed (return value == 0). - * After that point, any additional data starts a new frame. - * note : each frame is independent (does not reference any content from previous frame). - : note : multithreaded compression will block to flush as much output as possible. */ -} ZSTD_EndDirective; - +typedef enum { + ZSTD_e_continue=0, /* collect more data, encoder decides when to output compressed result, for optimal compression ratio */ + ZSTD_e_flush=1, /* flush any data provided so far, + * it creates (at least) one new block, that can be decoded immediately on reception; + * frame will continue: any future data can still reference previously compressed data, improving compression. + * note : multithreaded compression will block to flush as much output as possible. */ + ZSTD_e_end=2 /* flush any remaining data _and_ close current frame. + * note that frame is only closed after compressed data is fully flushed (return value == 0). + * After that point, any additional data starts a new frame. + * note : each frame is independent (does not reference any content from previous frame). + : note : multithreaded compression will block to flush as much output as possible. */ +} ZSTD_EndDirective; + /*! ZSTD_compressStream2() : Requires v1.4.0+ - * Behaves about the same as ZSTD_compressStream, with additional control on end directive. - * - Compression parameters are pushed into CCtx before starting compression, using ZSTD_CCtx_set*() - * - Compression parameters cannot be changed once compression is started (save a list of exceptions in multi-threading mode) - * - output->pos must be <= dstCapacity, input->pos must be <= srcSize - * - output->pos and input->pos will be updated. They are guaranteed to remain below their respective limit. + * Behaves about the same as ZSTD_compressStream, with additional control on end directive. + * - Compression parameters are pushed into CCtx before starting compression, using ZSTD_CCtx_set*() + * - Compression parameters cannot be changed once compression is started (save a list of exceptions in multi-threading mode) + * - output->pos must be <= dstCapacity, input->pos must be <= srcSize + * - output->pos and input->pos will be updated. They are guaranteed to remain below their respective limit. * - endOp must be a valid directive - * - When nbWorkers==0 (default), function is blocking : it completes its job before returning to caller. + * - When nbWorkers==0 (default), function is blocking : it completes its job before returning to caller. * - When nbWorkers>=1, function is non-blocking : it copies a portion of input, distributes jobs to internal worker threads, flush to output whatever is available, - * and then immediately returns, just indicating that there is some data remaining to be flushed. - * The function nonetheless guarantees forward progress : it will return only after it reads or write at least 1+ byte. - * - Exception : if the first call requests a ZSTD_e_end directive and provides enough dstCapacity, the function delegates to ZSTD_compress2() which is always blocking. - * - @return provides a minimum amount of data remaining to be flushed from internal buffers - * or an error code, which can be tested using ZSTD_isError(). - * if @return != 0, flush is not fully completed, there is still some data left within internal buffers. - * This is useful for ZSTD_e_flush, since in this case more flushes are necessary to empty all buffers. - * For ZSTD_e_end, @return == 0 when internal buffers are fully flushed and frame is completed. - * - after a ZSTD_e_end directive, if internal buffer is not fully flushed (@return != 0), - * only ZSTD_e_end or ZSTD_e_flush operations are allowed. - * Before starting a new compression job, or changing compression parameters, - * it is required to fully flush internal buffers. - */ -ZSTDLIB_API size_t ZSTD_compressStream2( ZSTD_CCtx* cctx, - ZSTD_outBuffer* output, - ZSTD_inBuffer* input, - ZSTD_EndDirective endOp); - + * and then immediately returns, just indicating that there is some data remaining to be flushed. + * The function nonetheless guarantees forward progress : it will return only after it reads or write at least 1+ byte. + * - Exception : if the first call requests a ZSTD_e_end directive and provides enough dstCapacity, the function delegates to ZSTD_compress2() which is always blocking. + * - @return provides a minimum amount of data remaining to be flushed from internal buffers + * or an error code, which can be tested using ZSTD_isError(). + * if @return != 0, flush is not fully completed, there is still some data left within internal buffers. + * This is useful for ZSTD_e_flush, since in this case more flushes are necessary to empty all buffers. + * For ZSTD_e_end, @return == 0 when internal buffers are fully flushed and frame is completed. + * - after a ZSTD_e_end directive, if internal buffer is not fully flushed (@return != 0), + * only ZSTD_e_end or ZSTD_e_flush operations are allowed. + * Before starting a new compression job, or changing compression parameters, + * it is required to fully flush internal buffers. + */ +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. @@ -729,9 +729,9 @@ ZSTDLIB_API size_t ZSTD_compressStream2( ZSTD_CCtx* cctx, * 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_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. */ - + /* ***************************************************************************** * This following is a legacy streaming API, available since v1.0+ . @@ -739,22 +739,22 @@ ZSTDLIB_API size_t ZSTD_CStreamOutSize(void); /**< recommended size for output * It is redundant, but remains fully supported. * Streaming in combination with 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); - */ + * 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() + * 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 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). */ ZSTDLIB_API size_t ZSTD_flushStream(ZSTD_CStream* zcs, ZSTD_outBuffer* output); @@ -769,142 +769,142 @@ ZSTDLIB_API size_t ZSTD_endStream(ZSTD_CStream* zcs, ZSTD_outBuffer* output); * Use ZSTD_createDStream() and ZSTD_freeDStream() to create/release resources. * ZSTD_DStream objects can be re-used multiple times. * -* Use ZSTD_initDStream() to start a new decompression operation. -* @return : recommended first input size -* Alternatively, use advanced API to set specific properties. +* Use ZSTD_initDStream() to start a new decompression operation. +* @return : recommended first input size +* Alternatively, use advanced API to set specific properties. * * Use ZSTD_decompressStream() repetitively to consume your input. * The function will update both `pos` fields. * If `input.pos < input.size`, some input has not been consumed. * It's up to the caller to present again remaining data. -* The function tries to flush all data decoded immediately, respecting output buffer size. +* The function tries to flush all data decoded immediately, respecting output buffer size. * If `output.pos < output.size`, decoder has flushed everything it could. -* But if `output.pos == output.size`, there might be some data left within internal buffers., -* In which case, call ZSTD_decompressStream() again to flush whatever remains in the buffer. -* Note : with no additional input provided, amount of data flushed is necessarily <= ZSTD_BLOCKSIZE_MAX. -* @return : 0 when a frame is completely decoded and fully flushed, -* or an error code, which can be tested using ZSTD_isError(), -* or any other value > 0, which means there is still some decoding or flushing to do to complete current frame : -* the return value is a suggested next input size (just a hint for better latency) -* that will never request more than the remaining frame size. +* But if `output.pos == output.size`, there might be some data left within internal buffers., +* In which case, call ZSTD_decompressStream() again to flush whatever remains in the buffer. +* Note : with no additional input provided, amount of data flushed is necessarily <= ZSTD_BLOCKSIZE_MAX. +* @return : 0 when a frame is completely decoded and fully flushed, +* or an error code, which can be tested using ZSTD_isError(), +* or any other value > 0, which means there is still some decoding or flushing to do to complete current frame : +* the return value is a suggested next input size (just a hint for better latency) +* that will never request more than the remaining frame size. * *******************************************************************************/ typedef ZSTD_DCtx ZSTD_DStream; /**< DCtx and DStream are now effectively same object (>= v1.3.0) */ - /* For compatibility with versions <= v1.2.0, prefer differentiating them. */ + /* For compatibility with versions <= v1.2.0, prefer differentiating them. */ /*===== ZSTD_DStream management functions =====*/ ZSTDLIB_API ZSTD_DStream* ZSTD_createDStream(void); ZSTDLIB_API size_t ZSTD_freeDStream(ZSTD_DStream* zds); /* accept NULL pointer */ /*===== Streaming decompression functions =====*/ - -/* This function is redundant with the advanced API and equivalent to: - * + +/* This function is redundant with the advanced API and equivalent to: + * * ZSTD_DCtx_reset(zds, ZSTD_reset_session_only); - * ZSTD_DCtx_refDDict(zds, NULL); - */ + * ZSTD_DCtx_refDDict(zds, NULL); + */ ZSTDLIB_API size_t ZSTD_initDStream(ZSTD_DStream* zds); - + ZSTDLIB_API size_t ZSTD_decompressStream(ZSTD_DStream* zds, ZSTD_outBuffer* output, ZSTD_inBuffer* input); 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), + +/************************** +* 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 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() : + * 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 or blocks using the same dictionary, * it's recommended to digest the dictionary only once, since it's a costly operation. * ZSTD_createCDict() will create a state from digesting a dictionary. * The resulting state can be used for future compression operations with very limited startup cost. - * ZSTD_CDict can be created once and shared by multiple threads concurrently, since its usage is read-only. + * 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. * Note 1 : Consider experimental function `ZSTD_createCDict_byReference()` if you prefer to not duplicate @dictBuffer content. * Note 2 : A ZSTD_CDict can be created from an empty @dictBuffer, * in which case the only thing that it transports is the @compressionLevel. * This can be useful in a pipeline featuring ZSTD_compress_usingCDict() exclusively, * expecting a ZSTD_CDict parameter with any data, including those without a known dictionary. */ -ZSTDLIB_API ZSTD_CDict* ZSTD_createCDict(const void* dictBuffer, size_t dictSize, - int compressionLevel); - -/*! ZSTD_freeCDict() : +ZSTDLIB_API ZSTD_CDict* ZSTD_createCDict(const void* dictBuffer, size_t dictSize, + int compressionLevel); + +/*! ZSTD_freeCDict() : * Function frees memory allocated by ZSTD_createCDict(). * If a NULL pointer is passed, no operation is performed. */ -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() : +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() * If a NULL pointer is passed, no operation is performed. */ -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); - - -/******************************** - * Dictionary helper functions - *******************************/ - +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); + + +/******************************** + * Dictionary helper functions + *******************************/ + /*! ZSTD_getDictID_fromDict() : Requires v1.4.0+ - * Provides the dictID stored within dictionary. - * if @return == 0, the dictionary is not conformant with Zstandard specification. - * It can still be loaded, but as a content-only dictionary. */ -ZSTDLIB_API unsigned ZSTD_getDictID_fromDict(const void* dict, size_t dictSize); - + * Provides the dictID stored within dictionary. + * if @return == 0, the dictionary is not conformant with Zstandard specification. + * It can still be loaded, but as a content-only dictionary. */ +ZSTDLIB_API unsigned ZSTD_getDictID_fromDict(const void* dict, size_t dictSize); + /*! ZSTD_getDictID_fromCDict() : Requires v1.5.0+ * Provides the dictID of the dictionary loaded into `cdict`. * If @return == 0, the dictionary is not conformant to Zstandard specification, or empty. @@ -912,108 +912,108 @@ ZSTDLIB_API unsigned ZSTD_getDictID_fromDict(const void* dict, size_t dictSize); ZSTDLIB_API unsigned ZSTD_getDictID_fromCDict(const ZSTD_CDict* cdict); /*! ZSTD_getDictID_fromDDict() : Requires v1.4.0+ - * Provides the dictID of the dictionary loaded into `ddict`. - * If @return == 0, the dictionary is not conformant to Zstandard specification, or empty. - * Non-conformant dictionaries can still be loaded, but as content-only dictionaries. */ -ZSTDLIB_API unsigned ZSTD_getDictID_fromDDict(const ZSTD_DDict* ddict); - + * Provides the dictID of the dictionary loaded into `ddict`. + * If @return == 0, the dictionary is not conformant to Zstandard specification, or empty. + * Non-conformant dictionaries can still be loaded, but as content-only dictionaries. */ +ZSTDLIB_API unsigned ZSTD_getDictID_fromDDict(const ZSTD_DDict* ddict); + /*! ZSTD_getDictID_fromFrame() : Requires v1.4.0+ - * Provides the dictID required to decompressed the frame stored within `src`. - * If @return == 0, the dictID could not be decoded. - * This could for one of the following reasons : - * - The frame does not require a dictionary to be decoded (most common case). - * - The frame was built with dictID intentionally removed. Whatever dictionary is necessary is a hidden information. - * Note : this use case also happens when using a non-conformant dictionary. - * - `srcSize` is too small, and as a result, the frame header could not be decoded (only possible if `srcSize < ZSTD_FRAMEHEADERSIZE_MAX`). - * - This is not a Zstandard frame. - * When identifying the exact failure cause, it's possible to use ZSTD_getFrameHeader(), which will provide a more precise error code. */ -ZSTDLIB_API unsigned ZSTD_getDictID_fromFrame(const void* src, size_t srcSize); - - -/******************************************************************************* + * Provides the dictID required to decompressed the frame stored within `src`. + * If @return == 0, the dictID could not be decoded. + * This could for one of the following reasons : + * - The frame does not require a dictionary to be decoded (most common case). + * - The frame was built with dictID intentionally removed. Whatever dictionary is necessary is a hidden information. + * Note : this use case also happens when using a non-conformant dictionary. + * - `srcSize` is too small, and as a result, the frame header could not be decoded (only possible if `srcSize < ZSTD_FRAMEHEADERSIZE_MAX`). + * - This is not a Zstandard frame. + * When identifying the exact failure cause, it's possible to use ZSTD_getFrameHeader(), which will provide a more precise error code. */ +ZSTDLIB_API unsigned ZSTD_getDictID_fromFrame(const void* src, size_t srcSize); + + +/******************************************************************************* * Advanced dictionary and prefix API (Requires v1.4.0+) - * - * This API allows dictionaries to be used with ZSTD_compress2(), + * + * This API allows dictionaries to be used with ZSTD_compress2(), * ZSTD_compressStream2(), and ZSTD_decompressDCtx(). 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. - ******************************************************************************/ - - + * only reset with the context is reset with ZSTD_reset_parameters or + * ZSTD_reset_session_and_parameters. Prefixes are single-use. + ******************************************************************************/ + + /*! ZSTD_CCtx_loadDictionary() : Requires v1.4.0+ - * 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); - + * 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() : Requires v1.4.0+ - * 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. + * 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 labelled 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); - + * 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() : Requires v1.4.0+ - * 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. + * 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_dct_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); - + * 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() : Requires v1.4.0+ - * 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); - + * 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() : Requires v1.4.0+ - * Reference a prepared dictionary, to be used to decompress next frames. - * The dictionary remains active for decompression of future frames using same DCtx. + * Reference a prepared dictionary, to be used to decompress next frames. + * The dictionary remains active for decompression of future frames using same DCtx. * * If called with ZSTD_d_refMultipleDDicts enabled, repeated calls of this function * will store the DDict references in a table, and the DDict used for decompression @@ -1021,53 +1021,53 @@ ZSTDLIB_API size_t ZSTD_DCtx_loadDictionary(ZSTD_DCtx* dctx, const void* dict, s * The memory for the table is allocated on the first call to refDDict, and can be * freed with ZSTD_freeDCtx(). * - * @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); - + * @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() : Requires v1.4.0+ - * 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. + * 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_dct_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 === */ - + * 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_*() : Requires v1.4.0+ - * These functions give the _current_ memory usage of selected object. - * Note that object memory usage can evolve (increase or decrease) over time. */ -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); -ZSTDLIB_API size_t ZSTD_sizeof_DStream(const ZSTD_DStream* zds); -ZSTDLIB_API size_t ZSTD_sizeof_CDict(const ZSTD_CDict* cdict); -ZSTDLIB_API size_t ZSTD_sizeof_DDict(const ZSTD_DDict* ddict); - + * These functions give the _current_ memory usage of selected object. + * Note that object memory usage can evolve (increase or decrease) over time. */ +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); +ZSTDLIB_API size_t ZSTD_sizeof_DStream(const ZSTD_DStream* zds); +ZSTDLIB_API size_t ZSTD_sizeof_CDict(const ZSTD_CDict* cdict); +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. + * 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. * Use them only in association with static linking. * ***************************************************************************************/ @@ -1108,73 +1108,73 @@ ZSTDLIB_API size_t ZSTD_sizeof_DDict(const ZSTD_DDict* ddict); # endif #endif /* ZSTD_DISABLE_DEPRECATE_WARNINGS */ -/**************************************************************************************** - * experimental API (static linking only) - **************************************************************************************** - * The following symbols and constants - * are not planned to join "stable API" status in the near future. - * They can still change in future versions. - * Some of them are planned to remain in the static_only section indefinitely. - * Some of them might be removed in the future (especially when redundant with existing stable functions) - * ***************************************************************************************/ +/**************************************************************************************** + * experimental API (static linking only) + **************************************************************************************** + * The following symbols and constants + * are not planned to join "stable API" status in the near future. + * They can still change in future versions. + * Some of them are planned to remain in the static_only section indefinitely. + * Some of them might be removed in the future (especially when redundant with existing stable functions) + * ***************************************************************************************/ #define ZSTD_FRAMEHEADERSIZE_PREFIX(format) ((format) == ZSTD_f_zstd1 ? 5 : 1) /* minimum input size required to query frame header size */ #define ZSTD_FRAMEHEADERSIZE_MIN(format) ((format) == ZSTD_f_zstd1 ? 6 : 2) -#define ZSTD_FRAMEHEADERSIZE_MAX 18 /* can be useful for static allocation */ -#define ZSTD_SKIPPABLEHEADERSIZE 8 - -/* compression parameter bounds */ -#define ZSTD_WINDOWLOG_MAX_32 30 -#define ZSTD_WINDOWLOG_MAX_64 31 -#define ZSTD_WINDOWLOG_MAX ((int)(sizeof(size_t) == 4 ? ZSTD_WINDOWLOG_MAX_32 : ZSTD_WINDOWLOG_MAX_64)) -#define ZSTD_WINDOWLOG_MIN 10 -#define ZSTD_HASHLOG_MAX ((ZSTD_WINDOWLOG_MAX < 30) ? ZSTD_WINDOWLOG_MAX : 30) -#define ZSTD_HASHLOG_MIN 6 -#define ZSTD_CHAINLOG_MAX_32 29 -#define ZSTD_CHAINLOG_MAX_64 30 -#define ZSTD_CHAINLOG_MAX ((int)(sizeof(size_t) == 4 ? ZSTD_CHAINLOG_MAX_32 : ZSTD_CHAINLOG_MAX_64)) -#define ZSTD_CHAINLOG_MIN ZSTD_HASHLOG_MIN -#define ZSTD_SEARCHLOG_MAX (ZSTD_WINDOWLOG_MAX-1) -#define ZSTD_SEARCHLOG_MIN 1 -#define ZSTD_MINMATCH_MAX 7 /* only for ZSTD_fast, other strategies are limited to 6 */ -#define ZSTD_MINMATCH_MIN 3 /* only for ZSTD_btopt+, faster strategies are limited to 4 */ -#define ZSTD_TARGETLENGTH_MAX ZSTD_BLOCKSIZE_MAX -#define ZSTD_TARGETLENGTH_MIN 0 /* note : comparing this constant to an unsigned results in a tautological test */ -#define ZSTD_STRATEGY_MIN ZSTD_fast -#define ZSTD_STRATEGY_MAX ZSTD_btultra2 - - -#define ZSTD_OVERLAPLOG_MIN 0 -#define ZSTD_OVERLAPLOG_MAX 9 - -#define ZSTD_WINDOWLOG_LIMIT_DEFAULT 27 /* by default, the streaming decoder will refuse any frame - * requiring larger than (1<<ZSTD_WINDOWLOG_LIMIT_DEFAULT) window size, - * to preserve host's memory from unreasonable requirements. - * This limit can be overridden using ZSTD_DCtx_setParameter(,ZSTD_d_windowLogMax,). - * The limit does not apply for one-pass decoders (such as ZSTD_decompress()), since no additional memory is allocated */ - - -/* LDM parameter bounds */ -#define ZSTD_LDM_HASHLOG_MIN ZSTD_HASHLOG_MIN -#define ZSTD_LDM_HASHLOG_MAX ZSTD_HASHLOG_MAX -#define ZSTD_LDM_MINMATCH_MIN 4 -#define ZSTD_LDM_MINMATCH_MAX 4096 -#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) - +#define ZSTD_FRAMEHEADERSIZE_MAX 18 /* can be useful for static allocation */ +#define ZSTD_SKIPPABLEHEADERSIZE 8 + +/* compression parameter bounds */ +#define ZSTD_WINDOWLOG_MAX_32 30 +#define ZSTD_WINDOWLOG_MAX_64 31 +#define ZSTD_WINDOWLOG_MAX ((int)(sizeof(size_t) == 4 ? ZSTD_WINDOWLOG_MAX_32 : ZSTD_WINDOWLOG_MAX_64)) +#define ZSTD_WINDOWLOG_MIN 10 +#define ZSTD_HASHLOG_MAX ((ZSTD_WINDOWLOG_MAX < 30) ? ZSTD_WINDOWLOG_MAX : 30) +#define ZSTD_HASHLOG_MIN 6 +#define ZSTD_CHAINLOG_MAX_32 29 +#define ZSTD_CHAINLOG_MAX_64 30 +#define ZSTD_CHAINLOG_MAX ((int)(sizeof(size_t) == 4 ? ZSTD_CHAINLOG_MAX_32 : ZSTD_CHAINLOG_MAX_64)) +#define ZSTD_CHAINLOG_MIN ZSTD_HASHLOG_MIN +#define ZSTD_SEARCHLOG_MAX (ZSTD_WINDOWLOG_MAX-1) +#define ZSTD_SEARCHLOG_MIN 1 +#define ZSTD_MINMATCH_MAX 7 /* only for ZSTD_fast, other strategies are limited to 6 */ +#define ZSTD_MINMATCH_MIN 3 /* only for ZSTD_btopt+, faster strategies are limited to 4 */ +#define ZSTD_TARGETLENGTH_MAX ZSTD_BLOCKSIZE_MAX +#define ZSTD_TARGETLENGTH_MIN 0 /* note : comparing this constant to an unsigned results in a tautological test */ +#define ZSTD_STRATEGY_MIN ZSTD_fast +#define ZSTD_STRATEGY_MAX ZSTD_btultra2 + + +#define ZSTD_OVERLAPLOG_MIN 0 +#define ZSTD_OVERLAPLOG_MAX 9 + +#define ZSTD_WINDOWLOG_LIMIT_DEFAULT 27 /* by default, the streaming decoder will refuse any frame + * requiring larger than (1<<ZSTD_WINDOWLOG_LIMIT_DEFAULT) window size, + * to preserve host's memory from unreasonable requirements. + * This limit can be overridden using ZSTD_DCtx_setParameter(,ZSTD_d_windowLogMax,). + * The limit does not apply for one-pass decoders (such as ZSTD_decompress()), since no additional memory is allocated */ + + +/* LDM parameter bounds */ +#define ZSTD_LDM_HASHLOG_MIN ZSTD_HASHLOG_MIN +#define ZSTD_LDM_HASHLOG_MAX ZSTD_HASHLOG_MAX +#define ZSTD_LDM_MINMATCH_MIN 4 +#define ZSTD_LDM_MINMATCH_MAX 4096 +#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 #define ZSTD_SRCSIZEHINT_MIN 0 #define ZSTD_SRCSIZEHINT_MAX INT_MAX - -/* --- Advanced types --- */ - -typedef struct ZSTD_CCtx_params_s ZSTD_CCtx_params; - + +/* --- Advanced types --- */ + +typedef struct ZSTD_CCtx_params_s ZSTD_CCtx_params; + typedef struct { unsigned int offset; /* The offset of the match. (NOT the same as the offset code) * If offset == 0 and matchLength == 0, this sequence represents the last @@ -1213,19 +1213,19 @@ typedef struct { } ZSTD_Sequence; typedef struct { - unsigned windowLog; /**< largest match distance : larger == more compression, more memory needed during decompression */ - unsigned chainLog; /**< fully searched segment : larger == more compression, slower, more memory (useless for fast) */ - unsigned hashLog; /**< dispatch table : larger == faster, more memory */ - unsigned searchLog; /**< nb of searches : larger == more compression, slower */ - unsigned minMatch; /**< match length searched : larger == faster decompression, sometimes less compression */ - unsigned targetLength; /**< acceptable match size for optimal parser (only) : larger == more compression, slower */ - ZSTD_strategy strategy; /**< see ZSTD_strategy definition above */ + unsigned windowLog; /**< largest match distance : larger == more compression, more memory needed during decompression */ + unsigned chainLog; /**< fully searched segment : larger == more compression, slower, more memory (useless for fast) */ + unsigned hashLog; /**< dispatch table : larger == faster, more memory */ + unsigned searchLog; /**< nb of searches : larger == more compression, slower */ + unsigned minMatch; /**< match length searched : larger == faster decompression, sometimes less compression */ + unsigned targetLength; /**< acceptable match size for optimal parser (only) : larger == more compression, slower */ + ZSTD_strategy strategy; /**< see ZSTD_strategy definition above */ } ZSTD_compressionParameters; typedef struct { - int contentSizeFlag; /**< 1: content size will be in frame header (when known) */ - int checksumFlag; /**< 1: generate a 32-bits checksum using XXH64 algorithm at end of frame, for error detection */ - int noDictIDFlag; /**< 1: no dictID will be saved into frame header (dictID is only useful for dictionary compression) */ + int contentSizeFlag; /**< 1: content size will be in frame header (when known) */ + int checksumFlag; /**< 1: generate a 32-bits checksum using XXH64 algorithm at end of frame, for error detection */ + int noDictIDFlag; /**< 1: no dictID will be saved into frame header (dictID is only useful for dictionary compression) */ } ZSTD_frameParameters; typedef struct { @@ -1234,24 +1234,24 @@ typedef struct { } ZSTD_parameters; typedef enum { - ZSTD_dct_auto = 0, /* dictionary is "full" when starting with ZSTD_MAGIC_DICTIONARY, otherwise it is "rawContent" */ - ZSTD_dct_rawContent = 1, /* ensures dictionary is always loaded as rawContent, even if it starts with ZSTD_MAGIC_DICTIONARY */ - ZSTD_dct_fullDict = 2 /* refuses to load a dictionary if it does not respect Zstandard's specification, starting with ZSTD_MAGIC_DICTIONARY */ + ZSTD_dct_auto = 0, /* dictionary is "full" when starting with ZSTD_MAGIC_DICTIONARY, otherwise it is "rawContent" */ + ZSTD_dct_rawContent = 1, /* ensures dictionary is always loaded as rawContent, even if it starts with ZSTD_MAGIC_DICTIONARY */ + ZSTD_dct_fullDict = 2 /* refuses to load a dictionary if it does not respect Zstandard's specification, starting with ZSTD_MAGIC_DICTIONARY */ } ZSTD_dictContentType_e; typedef enum { - ZSTD_dlm_byCopy = 0, /**< Copy dictionary content internally */ + ZSTD_dlm_byCopy = 0, /**< Copy dictionary content internally */ ZSTD_dlm_byRef = 1 /**< Reference dictionary content -- the dictionary buffer must outlive its users. */ } ZSTD_dictLoadMethod_e; -typedef enum { - ZSTD_f_zstd1 = 0, /* zstd frame format, specified in zstd_compression_format.md (default) */ +typedef enum { + ZSTD_f_zstd1 = 0, /* zstd frame format, specified in zstd_compression_format.md (default) */ ZSTD_f_zstd1_magicless = 1 /* 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 this instruction. */ -} ZSTD_format_e; + * Useful to save 4 bytes per generated frame. + * Decoder cannot recognise automatically this format, requiring this instruction. */ +} ZSTD_format_e; -typedef enum { +typedef enum { /* Note: this enum controls ZSTD_d_forceIgnoreChecksum */ ZSTD_d_validateChecksum = 0, ZSTD_d_ignoreChecksum = 1 @@ -1264,53 +1264,53 @@ typedef enum { } ZSTD_refMultipleDDicts_e; typedef enum { - /* Note: this enum and the behavior it controls are effectively internal - * implementation details of the compressor. They are expected to continue - * to evolve and should be considered only in the context of extremely - * advanced performance tuning. - * + /* Note: this enum and the behavior it controls are effectively internal + * implementation details of the compressor. They are expected to continue + * to evolve and should be considered only in the context of extremely + * advanced performance tuning. + * * Zstd currently supports the use of a CDict in three ways: - * - * - The contents of the CDict can be copied into the working context. This - * means that the compression can search both the dictionary and input - * while operating on a single set of internal tables. This makes - * the compression faster per-byte of input. However, the initial copy of - * the CDict's tables incurs a fixed cost at the beginning of the - * compression. For small compressions (< 8 KB), that copy can dominate - * the cost of the compression. - * - * - The CDict's tables can be used in-place. In this model, compression is - * slower per input byte, because the compressor has to search two sets of - * tables. However, this model incurs no start-up cost (as long as the - * working context's tables can be reused). For small inputs, this can be - * faster than copying the CDict's tables. - * + * + * - The contents of the CDict can be copied into the working context. This + * means that the compression can search both the dictionary and input + * while operating on a single set of internal tables. This makes + * the compression faster per-byte of input. However, the initial copy of + * the CDict's tables incurs a fixed cost at the beginning of the + * compression. For small compressions (< 8 KB), that copy can dominate + * the cost of the compression. + * + * - The CDict's tables can be used in-place. In this model, compression is + * slower per input byte, because the compressor has to search two sets of + * tables. However, this model incurs no start-up cost (as long as the + * working context's tables can be reused). For small inputs, this can be + * faster than copying the CDict's tables. + * * - The CDict's tables are not used at all, and instead we use the working * context alone to reload the dictionary and use params based on the source * size. See ZSTD_compress_insertDictionary() and ZSTD_compress_usingDict(). * This method is effective when the dictionary sizes are very small relative * to the input size, and the input size is fairly large to begin with. * - * Zstd has a simple internal heuristic that selects which strategy to use - * at the beginning of a compression. However, if experimentation shows that - * Zstd is making poor choices, it is possible to override that choice with - * this enum. - */ - ZSTD_dictDefaultAttach = 0, /* Use the default heuristic. */ - ZSTD_dictForceAttach = 1, /* Never copy the dictionary. */ - ZSTD_dictForceCopy = 2, /* Always copy the dictionary. */ + * Zstd has a simple internal heuristic that selects which strategy to use + * at the beginning of a compression. However, if experimentation shows that + * Zstd is making poor choices, it is possible to override that choice with + * this enum. + */ + ZSTD_dictDefaultAttach = 0, /* Use the default heuristic. */ + ZSTD_dictForceAttach = 1, /* Never copy the dictionary. */ + ZSTD_dictForceCopy = 2, /* Always copy the dictionary. */ ZSTD_dictForceLoad = 3 /* Always reload the dictionary */ -} ZSTD_dictAttachPref_e; - -typedef enum { - ZSTD_lcm_auto = 0, /**< Automatically determine the compression mode based on the compression level. - * Negative compression levels will be uncompressed, and positive compression - * levels will be compressed. */ - ZSTD_lcm_huffman = 1, /**< Always attempt Huffman compression. Uncompressed literals will still be - * emitted if Huffman compression is not profitable. */ +} ZSTD_dictAttachPref_e; + +typedef enum { + ZSTD_lcm_auto = 0, /**< Automatically determine the compression mode based on the compression level. + * Negative compression levels will be uncompressed, and positive compression + * levels will be compressed. */ + ZSTD_lcm_huffman = 1, /**< Always attempt Huffman compression. Uncompressed literals will still be + * emitted if Huffman compression is not profitable. */ ZSTD_lcm_uncompressed = 2 /**< Always emit uncompressed literals. */ -} ZSTD_literalCompressionMode_e; - +} ZSTD_literalCompressionMode_e; + typedef enum { /* Note: This enum controls features which are conditionally beneficial. Zstd typically will make a final * decision on whether or not to enable the feature (ZSTD_ps_auto), but setting the switch to ZSTD_ps_enable @@ -1320,15 +1320,15 @@ typedef enum { ZSTD_ps_enable = 1, /* Force-enable the feature */ ZSTD_ps_disable = 2 /* Do not use the feature */ } ZSTD_paramSwitch_e; - + /*************************************** * Frame size functions ***************************************/ /*! ZSTD_findDecompressedSize() : - * `src` should point to the start of a series of ZSTD encoded and/or skippable frames + * `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`) + * (i.e. there should be a frame boundary at `src + srcSize`) * @return : - decompressed size of all data in all successive frames * - if the decompressed size cannot be determined: ZSTD_CONTENTSIZE_UNKNOWN * - if an error occurred: ZSTD_CONTENTSIZE_ERROR @@ -1349,24 +1349,24 @@ typedef enum { ZSTDLIB_STATIC_API unsigned long long ZSTD_findDecompressedSize(const void* src, size_t srcSize); /*! 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 + * `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 occurred: ZSTD_CONTENTSIZE_ERROR - * - * note 1 : an error can occur if `src` contains an invalid or incorrectly formatted frame. - * note 2 : the upper-bound is exact when the decompressed size field is available in every ZSTD encoded frame of `src`. - * in this case, `ZSTD_findDecompressedSize` and `ZSTD_decompressBound` return the same value. - * note 3 : when the decompressed size field isn't available, the upper-bound for that frame is calculated by: - * upper-bound = # blocks * min(128 KB, Window_Size) - */ + * + * note 1 : an error can occur if `src` contains an invalid or incorrectly formatted frame. + * note 2 : the upper-bound is exact when the decompressed size field is available in every ZSTD encoded frame of `src`. + * in this case, `ZSTD_findDecompressedSize` and `ZSTD_decompressBound` return the same value. + * note 3 : when the decompressed size field isn't available, the upper-bound for that frame is calculated by: + * upper-bound = # blocks * min(128 KB, Window_Size) + */ ZSTDLIB_STATIC_API unsigned long long ZSTD_decompressBound(const void* src, size_t srcSize); - + /*! ZSTD_frameHeaderSize() : - * srcSize must be >= ZSTD_FRAMEHEADERSIZE_PREFIX. - * @return : size of the Frame Header, - * or an error code (if srcSize is too small) */ + * srcSize must be >= ZSTD_FRAMEHEADERSIZE_PREFIX. + * @return : size of the Frame Header, + * or an error code (if srcSize is too small) */ ZSTDLIB_STATIC_API size_t ZSTD_frameHeaderSize(const void* src, size_t srcSize); typedef enum { @@ -1513,7 +1513,7 @@ ZSTDLIB_STATIC_API size_t ZSTD_estimateDCtxSize(void); * It will also consider src size to be arbitrarily "large", which is worst case. * 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_CCtxParams_setParameter(). Only single-threaded compression is supported. This function will return an error code if ZSTD_c_nbWorkers is >= 1. + * ZSTD_estimateCStreamSize_usingCCtxParams() can be used in tandem with ZSTD_CCtxParams_setParameter(). Only single-threaded compression is supported. This function will return an error code if ZSTD_c_nbWorkers is >= 1. * Note : CStream size 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, @@ -1576,7 +1576,7 @@ ZSTDLIB_STATIC_API const ZSTD_DDict* ZSTD_initStaticDDict( ZSTD_dictLoadMethod_e dictLoadMethod, ZSTD_dictContentType_e dictContentType); - + /*! Custom memory allocation : * These prototypes make it possible to pass your own allocation/free functions. * ZSTD_customMem is provided at creation time, using ZSTD_create*_advanced() variants listed below. @@ -1641,33 +1641,33 @@ ZSTDLIB_STATIC_API ZSTD_DDict* ZSTD_createDDict_advanced( /*! ZSTD_createCDict_byReference() : * Create a digested dictionary for compression - * Dictionary content is just referenced, not duplicated. - * As a consequence, `dictBuffer` **must** outlive CDict, + * Dictionary content is just referenced, not duplicated. + * As a consequence, `dictBuffer` **must** outlive CDict, * and its content must remain unmodified throughout the lifetime of CDict. * note: equivalent to ZSTD_createCDict_advanced(), with dictLoadMethod==ZSTD_dlm_byRef */ ZSTDLIB_STATIC_API ZSTD_CDict* ZSTD_createCDict_byReference(const void* dictBuffer, size_t dictSize, int compressionLevel); /*! ZSTD_getCParams() : - * @return ZSTD_compressionParameters structure for a selected compression level and estimated srcSize. - * `estimatedSrcSize` value is optional, select 0 if not known */ + * @return ZSTD_compressionParameters structure for a selected compression level and estimated srcSize. + * `estimatedSrcSize` value is optional, select 0 if not known */ ZSTDLIB_STATIC_API ZSTD_compressionParameters ZSTD_getCParams(int compressionLevel, unsigned long long estimatedSrcSize, size_t dictSize); /*! ZSTD_getParams() : - * same as ZSTD_getCParams(), but @return a full `ZSTD_parameters` object instead of sub-component `ZSTD_compressionParameters`. - * All fields of `ZSTD_frameParameters` are set to default : contentSize=1, checksum=0, noDictID=0 */ + * same as ZSTD_getCParams(), but @return a full `ZSTD_parameters` object instead of sub-component `ZSTD_compressionParameters`. + * All fields of `ZSTD_frameParameters` are set to default : contentSize=1, checksum=0, noDictID=0 */ ZSTDLIB_STATIC_API ZSTD_parameters ZSTD_getParams(int compressionLevel, unsigned long long estimatedSrcSize, size_t dictSize); /*! ZSTD_checkCParams() : - * Ensure param values remain within authorized range. - * @return 0 on success, or an error code (can be checked with ZSTD_isError()) */ + * Ensure param values remain within authorized range. + * @return 0 on success, or an error code (can be checked with ZSTD_isError()) */ ZSTDLIB_STATIC_API size_t ZSTD_checkCParams(ZSTD_compressionParameters params); /*! ZSTD_adjustCParams() : * optimize params for a given `srcSize` and `dictSize`. - * `srcSize` can be unknown, in which case use ZSTD_CONTENTSIZE_UNKNOWN. - * `dictSize` must be `0` when there is no dictionary. - * cPar can be invalid : all parameters will be clamped within valid range in the @return struct. - * This function never fails (wide contract) */ + * `srcSize` can be unknown, in which case use ZSTD_CONTENTSIZE_UNKNOWN. + * `dictSize` must be `0` when there is no dictionary. + * cPar can be invalid : all parameters will be clamped within valid range in the @return struct. + * This function never fails (wide contract) */ ZSTDLIB_STATIC_API ZSTD_compressionParameters ZSTD_adjustCParams(ZSTD_compressionParameters cPar, unsigned long long srcSize, size_t dictSize); /*! ZSTD_compress_advanced() : @@ -1676,10 +1676,10 @@ ZSTDLIB_STATIC_API ZSTD_compressionParameters ZSTD_adjustCParams(ZSTD_compressio * This prototype will generate compilation warnings. */ ZSTD_DEPRECATED("use ZSTD_compress2") size_t ZSTD_compress_advanced(ZSTD_CCtx* cctx, - void* dst, size_t dstCapacity, - const void* src, size_t srcSize, - const void* dict,size_t dictSize, - ZSTD_parameters params); + void* dst, size_t dstCapacity, + const void* src, size_t srcSize, + const void* dict,size_t dictSize, + ZSTD_parameters params); /*! ZSTD_compress_usingCDict_advanced() : * Note : this function is now DEPRECATED. @@ -1687,65 +1687,65 @@ size_t ZSTD_compress_advanced(ZSTD_CCtx* cctx, * This prototype will generate compilation warnings. */ ZSTD_DEPRECATED("use ZSTD_compress2 with ZSTD_CCtx_loadDictionary") size_t ZSTD_compress_usingCDict_advanced(ZSTD_CCtx* cctx, - void* dst, size_t dstCapacity, - const void* src, size_t srcSize, - const ZSTD_CDict* cdict, - ZSTD_frameParameters fParams); + void* dst, size_t dstCapacity, + const void* src, size_t srcSize, + const ZSTD_CDict* cdict, + ZSTD_frameParameters fParams); -/*! ZSTD_CCtx_loadDictionary_byReference() : - * Same as ZSTD_CCtx_loadDictionary(), but dictionary content is referenced, instead of being copied into CCtx. - * It saves some memory, but also requires that `dict` outlives its usage within `cctx` */ +/*! ZSTD_CCtx_loadDictionary_byReference() : + * Same as ZSTD_CCtx_loadDictionary(), but dictionary content is referenced, instead of being copied into CCtx. + * It saves some memory, but also requires that `dict` outlives its usage within `cctx` */ ZSTDLIB_STATIC_API size_t ZSTD_CCtx_loadDictionary_byReference(ZSTD_CCtx* cctx, const void* dict, size_t dictSize); -/*! ZSTD_CCtx_loadDictionary_advanced() : - * Same as ZSTD_CCtx_loadDictionary(), but gives finer control over - * how to load the dictionary (by copy ? by reference ?) - * and how to interpret it (automatic ? force raw mode ? full mode only ?) */ +/*! ZSTD_CCtx_loadDictionary_advanced() : + * Same as ZSTD_CCtx_loadDictionary(), but gives finer control over + * how to load the dictionary (by copy ? by reference ?) + * and how to interpret it (automatic ? force raw mode ? full mode only ?) */ ZSTDLIB_STATIC_API size_t ZSTD_CCtx_loadDictionary_advanced(ZSTD_CCtx* cctx, const void* dict, size_t dictSize, ZSTD_dictLoadMethod_e dictLoadMethod, ZSTD_dictContentType_e dictContentType); - -/*! ZSTD_CCtx_refPrefix_advanced() : - * Same as ZSTD_CCtx_refPrefix(), but gives finer control over - * how to interpret prefix content (automatic ? force raw mode (default) ? full mode only ?) */ + +/*! ZSTD_CCtx_refPrefix_advanced() : + * Same as ZSTD_CCtx_refPrefix(), but gives finer control over + * how to interpret prefix content (automatic ? force raw mode (default) ? full mode only ?) */ ZSTDLIB_STATIC_API size_t ZSTD_CCtx_refPrefix_advanced(ZSTD_CCtx* cctx, const void* prefix, size_t prefixSize, ZSTD_dictContentType_e dictContentType); - -/* === experimental parameters === */ -/* these parameters can be used with ZSTD_setParameter() - * they are not guaranteed to remain supported in the future */ - - /* Enables rsyncable mode, - * which makes compressed files more rsync friendly - * by adding periodic synchronization points to the compressed data. - * The target average block size is ZSTD_c_jobSize / 2. - * It's possible to modify the job size to increase or decrease - * the granularity of the synchronization point. - * Once the jobSize is smaller than the window size, - * it will result in compression ratio degradation. - * NOTE 1: rsyncable mode only works when multithreading is enabled. - * NOTE 2: rsyncable performs poorly in combination with long range mode, - * since it will decrease the effectiveness of synchronization points, - * though mileage may vary. - * NOTE 3: Rsyncable mode limits maximum compression speed to ~400 MB/s. - * If the selected compression level is already running significantly slower, - * the overall speed won't be significantly impacted. - */ - #define ZSTD_c_rsyncable ZSTD_c_experimentalParam1 - -/* Select a compression format. - * The value must be of type ZSTD_format_e. - * See ZSTD_format_e enum definition for details */ -#define ZSTD_c_format ZSTD_c_experimentalParam2 - -/* Force back-reference distances to remain < windowSize, - * even when referencing into Dictionary content (default:0) */ -#define ZSTD_c_forceMaxWindow ZSTD_c_experimentalParam3 - -/* Controls whether the contents of a CDict - * are used in place, or copied into the working context. - * Accepts values from the ZSTD_dictAttachPref_e enum. - * See the comments on that enum for an explanation of the feature. */ -#define ZSTD_c_forceAttachDict ZSTD_c_experimentalParam4 - + +/* === experimental parameters === */ +/* these parameters can be used with ZSTD_setParameter() + * they are not guaranteed to remain supported in the future */ + + /* Enables rsyncable mode, + * which makes compressed files more rsync friendly + * by adding periodic synchronization points to the compressed data. + * The target average block size is ZSTD_c_jobSize / 2. + * It's possible to modify the job size to increase or decrease + * the granularity of the synchronization point. + * Once the jobSize is smaller than the window size, + * it will result in compression ratio degradation. + * NOTE 1: rsyncable mode only works when multithreading is enabled. + * NOTE 2: rsyncable performs poorly in combination with long range mode, + * since it will decrease the effectiveness of synchronization points, + * though mileage may vary. + * NOTE 3: Rsyncable mode limits maximum compression speed to ~400 MB/s. + * If the selected compression level is already running significantly slower, + * the overall speed won't be significantly impacted. + */ + #define ZSTD_c_rsyncable ZSTD_c_experimentalParam1 + +/* Select a compression format. + * The value must be of type ZSTD_format_e. + * See ZSTD_format_e enum definition for details */ +#define ZSTD_c_format ZSTD_c_experimentalParam2 + +/* Force back-reference distances to remain < windowSize, + * even when referencing into Dictionary content (default:0) */ +#define ZSTD_c_forceMaxWindow ZSTD_c_experimentalParam3 + +/* Controls whether the contents of a CDict + * are used in place, or copied into the working context. + * Accepts values from the ZSTD_dictAttachPref_e enum. + * See the comments on that enum for an explanation of the feature. */ +#define ZSTD_c_forceAttachDict ZSTD_c_experimentalParam4 + /* Controlled with ZSTD_paramSwitch_e enum. * Default is ZSTD_ps_auto. * Set to ZSTD_ps_disable to never compress literals. @@ -1755,9 +1755,9 @@ ZSTDLIB_STATIC_API size_t ZSTD_CCtx_refPrefix_advanced(ZSTD_CCtx* cctx, const vo * By default, in ZSTD_ps_auto, the library will decide at runtime whether to use * literals compression based on the compression parameters - specifically, * negative compression levels do not use literal compression. - */ -#define ZSTD_c_literalCompressionMode ZSTD_c_experimentalParam5 - + */ +#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) */ @@ -1949,95 +1949,95 @@ ZSTDLIB_STATIC_API size_t ZSTD_CCtx_refPrefix_advanced(ZSTD_CCtx* cctx, const vo */ #define ZSTD_c_deterministicRefPrefix ZSTD_c_experimentalParam15 -/*! 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()). - */ +/*! 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()). + */ ZSTDLIB_STATIC_API size_t ZSTD_CCtx_getParameter(const ZSTD_CCtx* cctx, ZSTD_cParameter param, int* value); - - -/*! ZSTD_CCtx_params : - * Quick howto : - * - ZSTD_createCCtxParams() : Create a ZSTD_CCtx_params structure - * - ZSTD_CCtxParams_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 frames. - * - ZSTD_compressStream2() : Do compression using the CCtx. + + +/*! ZSTD_CCtx_params : + * Quick howto : + * - ZSTD_createCCtxParams() : Create a ZSTD_CCtx_params structure + * - ZSTD_CCtxParams_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 frames. + * - ZSTD_compressStream2() : Do compression using the CCtx. * - ZSTD_freeCCtxParams() : Free the memory, accept NULL pointer. - * - * This can be used with ZSTD_estimateCCtxSize_advanced_usingCCtxParams() - * for static allocation of CCtx for single-threaded compression. - */ + * + * This can be used with ZSTD_estimateCCtxSize_advanced_usingCCtxParams() + * for static allocation of CCtx for single-threaded compression. + */ ZSTDLIB_STATIC_API ZSTD_CCtx_params* ZSTD_createCCtxParams(void); ZSTDLIB_STATIC_API size_t ZSTD_freeCCtxParams(ZSTD_CCtx_params* params); /* accept NULL pointer */ - -/*! ZSTD_CCtxParams_reset() : - * Reset params to default values. - */ + +/*! ZSTD_CCtxParams_reset() : + * Reset params to default values. + */ ZSTDLIB_STATIC_API size_t ZSTD_CCtxParams_reset(ZSTD_CCtx_params* params); - -/*! ZSTD_CCtxParams_init() : - * Initializes the compression parameters of cctxParams according to - * compression level. All other parameters are reset to their default values. - */ + +/*! ZSTD_CCtxParams_init() : + * Initializes the compression parameters of cctxParams according to + * compression level. All other parameters are reset to their default values. + */ ZSTDLIB_STATIC_API size_t ZSTD_CCtxParams_init(ZSTD_CCtx_params* cctxParams, int compressionLevel); - -/*! ZSTD_CCtxParams_init_advanced() : - * Initializes the compression and frame parameters of cctxParams according to - * params. All other parameters are reset to their default values. - */ + +/*! ZSTD_CCtxParams_init_advanced() : + * Initializes the compression and frame parameters of cctxParams according to + * params. All other parameters are reset to their default values. + */ ZSTDLIB_STATIC_API size_t ZSTD_CCtxParams_init_advanced(ZSTD_CCtx_params* cctxParams, ZSTD_parameters params); - + /*! ZSTD_CCtxParams_setParameter() : Requires v1.4.0+ - * Similar to ZSTD_CCtx_setParameter. - * Set one compression parameter, selected by enum ZSTD_cParameter. + * Similar to ZSTD_CCtx_setParameter. + * Set one compression parameter, selected by enum ZSTD_cParameter. * Parameters must be applied to a ZSTD_CCtx using * ZSTD_CCtx_setParametersUsingCCtxParams(). * @result : a code representing success or failure (which can be tested with * ZSTD_isError()). - */ + */ ZSTDLIB_STATIC_API size_t ZSTD_CCtxParams_setParameter(ZSTD_CCtx_params* params, ZSTD_cParameter param, int value); - -/*! ZSTD_CCtxParams_getParameter() : - * Similar to ZSTD_CCtx_getParameter. - * Get the requested value of one compression parameter, selected by enum ZSTD_cParameter. - * @result : 0, or an error code (which can be tested with ZSTD_isError()). - */ + +/*! ZSTD_CCtxParams_getParameter() : + * Similar to ZSTD_CCtx_getParameter. + * Get the requested value of one compression parameter, selected by enum ZSTD_cParameter. + * @result : 0, or an error code (which can be tested with ZSTD_isError()). + */ ZSTDLIB_STATIC_API size_t ZSTD_CCtxParams_getParameter(const ZSTD_CCtx_params* params, ZSTD_cParameter param, int* value); - -/*! ZSTD_CCtx_setParametersUsingCCtxParams() : - * Apply a set of ZSTD_CCtx_params to the compression context. - * This can be done even after compression is started, - * if nbWorkers==0, this will have no impact until a new compression is started. - * if nbWorkers>=1, new parameters will be picked up at next job, - * with a few restrictions (windowLog, pledgedSrcSize, nbWorkers, jobSize, and overlapLog are not updated). - */ + +/*! ZSTD_CCtx_setParametersUsingCCtxParams() : + * Apply a set of ZSTD_CCtx_params to the compression context. + * This can be done even after compression is started, + * if nbWorkers==0, this will have no impact until a new compression is started. + * if nbWorkers>=1, new parameters will be picked up at next job, + * with a few restrictions (windowLog, pledgedSrcSize, nbWorkers, jobSize, and overlapLog are not updated). + */ ZSTDLIB_STATIC_API size_t ZSTD_CCtx_setParametersUsingCCtxParams( - ZSTD_CCtx* cctx, const ZSTD_CCtx_params* params); - -/*! ZSTD_compressStream2_simpleArgs() : - * Same as ZSTD_compressStream2(), - * but using only integral types as arguments. - * This variant might be helpful for binders from dynamic languages - * which have troubles handling structures containing memory pointers. - */ + ZSTD_CCtx* cctx, const ZSTD_CCtx_params* params); + +/*! ZSTD_compressStream2_simpleArgs() : + * Same as ZSTD_compressStream2(), + * but using only integral types as arguments. + * This variant might be helpful for binders from dynamic languages + * which have troubles handling structures containing memory pointers. + */ ZSTDLIB_STATIC_API size_t ZSTD_compressStream2_simpleArgs ( - ZSTD_CCtx* cctx, - void* dst, size_t dstCapacity, size_t* dstPos, - const void* src, size_t srcSize, size_t* srcPos, - ZSTD_EndDirective endOp); - - -/*************************************** -* Advanced decompression functions -***************************************/ - + ZSTD_CCtx* cctx, + void* dst, size_t dstCapacity, size_t* dstPos, + const void* src, size_t srcSize, size_t* srcPos, + ZSTD_EndDirective endOp); + + +/*************************************** +* Advanced decompression functions +***************************************/ + /*! ZSTD_isFrame() : * Tells if the content of `buffer` starts with a valid Frame Identifier. * Note : Frame Identifier is 4 bytes. If `size < 4`, @return will always be 0. @@ -2052,32 +2052,32 @@ ZSTDLIB_STATIC_API unsigned ZSTD_isFrame(const void* buffer, size_t size); * it must remain read accessible throughout the lifetime of DDict */ ZSTDLIB_STATIC_API ZSTD_DDict* ZSTD_createDDict_byReference(const void* dictBuffer, size_t dictSize); -/*! ZSTD_DCtx_loadDictionary_byReference() : - * Same as ZSTD_DCtx_loadDictionary(), - * but references `dict` content instead of copying it into `dctx`. - * This saves memory if `dict` remains around., - * However, it's imperative that `dict` remains accessible (and unmodified) while being used, so it must outlive decompression. */ +/*! ZSTD_DCtx_loadDictionary_byReference() : + * Same as ZSTD_DCtx_loadDictionary(), + * but references `dict` content instead of copying it into `dctx`. + * This saves memory if `dict` remains around., + * However, it's imperative that `dict` remains accessible (and unmodified) while being used, so it must outlive decompression. */ ZSTDLIB_STATIC_API size_t ZSTD_DCtx_loadDictionary_byReference(ZSTD_DCtx* dctx, const void* dict, size_t dictSize); -/*! ZSTD_DCtx_loadDictionary_advanced() : - * Same as ZSTD_DCtx_loadDictionary(), - * but gives direct control over - * how to load the dictionary (by copy ? by reference ?) - * and how to interpret it (automatic ? force raw mode ? full mode only ?). */ +/*! ZSTD_DCtx_loadDictionary_advanced() : + * Same as ZSTD_DCtx_loadDictionary(), + * but gives direct control over + * how to load the dictionary (by copy ? by reference ?) + * and how to interpret it (automatic ? force raw mode ? full mode only ?). */ ZSTDLIB_STATIC_API size_t ZSTD_DCtx_loadDictionary_advanced(ZSTD_DCtx* dctx, const void* dict, size_t dictSize, ZSTD_dictLoadMethod_e dictLoadMethod, ZSTD_dictContentType_e dictContentType); -/*! ZSTD_DCtx_refPrefix_advanced() : - * Same as ZSTD_DCtx_refPrefix(), but gives finer control over - * how to interpret prefix content (automatic ? force raw mode (default) ? full mode only ?) */ +/*! ZSTD_DCtx_refPrefix_advanced() : + * Same as ZSTD_DCtx_refPrefix(), but gives finer control over + * how to interpret prefix content (automatic ? force raw mode (default) ? full mode only ?) */ ZSTDLIB_STATIC_API size_t ZSTD_DCtx_refPrefix_advanced(ZSTD_DCtx* dctx, const void* prefix, size_t prefixSize, ZSTD_dictContentType_e dictContentType); -/*! ZSTD_DCtx_setMaxWindowSize() : - * Refuses allocating internal buffers for frames requiring a window size larger than provided limit. - * This protects 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 single-pass mode. - * By default, a decompression context accepts all window sizes <= (1 << ZSTD_WINDOWLOG_LIMIT_DEFAULT) - * @return : 0, or an error code (which can be tested using ZSTD_isError()). - */ +/*! ZSTD_DCtx_setMaxWindowSize() : + * Refuses allocating internal buffers for frames requiring a window size larger than provided limit. + * This protects 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 single-pass mode. + * By default, a decompression context accepts all window sizes <= (1 << ZSTD_WINDOWLOG_LIMIT_DEFAULT) + * @return : 0, or an error code (which can be tested using ZSTD_isError()). + */ ZSTDLIB_STATIC_API size_t ZSTD_DCtx_setMaxWindowSize(ZSTD_DCtx* dctx, size_t maxWindowSize); /*! ZSTD_DCtx_getParameter() : @@ -2087,11 +2087,11 @@ ZSTDLIB_STATIC_API size_t ZSTD_DCtx_setMaxWindowSize(ZSTD_DCtx* dctx, size_t max */ ZSTDLIB_STATIC_API size_t ZSTD_DCtx_getParameter(ZSTD_DCtx* dctx, ZSTD_dParameter param, int* value); -/* ZSTD_d_format - * experimental parameter, - * allowing selection between ZSTD_format_e input compression formats - */ -#define ZSTD_d_format ZSTD_d_experimentalParam1 +/* ZSTD_d_format + * experimental parameter, + * allowing selection between ZSTD_format_e input compression formats + */ +#define ZSTD_d_format ZSTD_d_experimentalParam1 /* ZSTD_d_stableOutBuffer * Experimental parameter. * Default is 0 == disabled. Set to 1 to enable. @@ -2159,48 +2159,48 @@ ZSTDLIB_STATIC_API size_t ZSTD_DCtx_getParameter(ZSTD_DCtx* dctx, ZSTD_dParamete #define ZSTD_d_refMultipleDDicts ZSTD_d_experimentalParam4 -/*! ZSTD_DCtx_setFormat() : +/*! ZSTD_DCtx_setFormat() : * This function is REDUNDANT. Prefer ZSTD_DCtx_setParameter(). - * 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()). */ + * 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()). */ ZSTD_DEPRECATED("use ZSTD_DCtx_setParameter() instead") size_t ZSTD_DCtx_setFormat(ZSTD_DCtx* dctx, ZSTD_format_e format); - -/*! ZSTD_decompressStream_simpleArgs() : - * Same as ZSTD_decompressStream(), - * but using only integral types as arguments. - * This can be helpful for binders from dynamic languages - * which have troubles handling structures containing memory pointers. - */ + +/*! ZSTD_decompressStream_simpleArgs() : + * Same as ZSTD_decompressStream(), + * but using only integral types as arguments. + * This can be helpful for binders from dynamic languages + * which have troubles handling structures containing memory pointers. + */ ZSTDLIB_STATIC_API size_t ZSTD_decompressStream_simpleArgs ( - ZSTD_DCtx* dctx, - void* dst, size_t dstCapacity, size_t* dstPos, - const void* src, size_t srcSize, size_t* srcPos); - - + ZSTD_DCtx* dctx, + void* dst, size_t dstCapacity, size_t* dstPos, + const void* src, size_t srcSize, size_t* srcPos); + + /******************************************************************** * Advanced streaming functions -* Warning : most of these functions are now redundant with the Advanced API. -* Once Advanced API reaches "stable" status, -* redundant functions will be deprecated, and then at some point removed. +* Warning : most of these functions are now redundant with the Advanced API. +* Once Advanced API reaches "stable" status, +* redundant functions will be deprecated, and then at some point removed. ********************************************************************/ /*===== Advanced Streaming compression functions =====*/ /*! ZSTD_initCStream_srcSize() : * This function is DEPRECATED, and 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); - * ZSTD_CCtx_setPledgedSrcSize(zcs, pledgedSrcSize); - * - * pledgedSrcSize must be correct. If it is not known at init time, use - * ZSTD_CONTENTSIZE_UNKNOWN. Note that, for compatibility with older programs, - * "0" also disables frame content size field. It may be enabled in the future. + * 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); + * ZSTD_CCtx_setPledgedSrcSize(zcs, pledgedSrcSize); + * + * pledgedSrcSize must be correct. If it is not known at init time, use + * ZSTD_CONTENTSIZE_UNKNOWN. Note that, for compatibility with older programs, + * "0" also disables frame content size field. It may be enabled in the future. * This prototype will generate compilation warnings. - */ + */ ZSTD_DEPRECATED("use ZSTD_CCtx_reset, see zstd.h for detailed instructions") size_t ZSTD_initCStream_srcSize(ZSTD_CStream* zcs, int compressionLevel, @@ -2208,16 +2208,16 @@ size_t ZSTD_initCStream_srcSize(ZSTD_CStream* zcs, /*! ZSTD_initCStream_usingDict() : * This function is DEPRECATED, and is equivalent to: - * ZSTD_CCtx_reset(zcs, ZSTD_reset_session_only); - * ZSTD_CCtx_setParameter(zcs, ZSTD_c_compressionLevel, compressionLevel); - * ZSTD_CCtx_loadDictionary(zcs, dict, dictSize); - * - * Creates of an internal CDict (incompatible with static CCtx), except if - * dict == NULL or dictSize < 8, in which case no dict is used. + * ZSTD_CCtx_reset(zcs, ZSTD_reset_session_only); + * ZSTD_CCtx_setParameter(zcs, ZSTD_c_compressionLevel, compressionLevel); + * ZSTD_CCtx_loadDictionary(zcs, dict, dictSize); + * + * Creates of an internal CDict (incompatible with static CCtx), except if + * dict == NULL or dictSize < 8, in which case no dict is used. * Note: dict is loaded with ZSTD_dct_auto (treated as a full zstd dictionary if - * it begins with ZSTD_MAGIC_DICTIONARY, else as raw content) and ZSTD_dlm_byCopy. + * it begins with ZSTD_MAGIC_DICTIONARY, else as raw content) and ZSTD_dlm_byCopy. * This prototype will generate compilation warnings. - */ + */ ZSTD_DEPRECATED("use ZSTD_CCtx_reset, see zstd.h for detailed instructions") size_t ZSTD_initCStream_usingDict(ZSTD_CStream* zcs, const void* dict, size_t dictSize, @@ -2225,19 +2225,19 @@ size_t ZSTD_initCStream_usingDict(ZSTD_CStream* zcs, /*! ZSTD_initCStream_advanced() : * This function is DEPRECATED, and is approximately equivalent to: - * ZSTD_CCtx_reset(zcs, ZSTD_reset_session_only); + * ZSTD_CCtx_reset(zcs, ZSTD_reset_session_only); * // Pseudocode: Set each zstd parameter and leave the rest as-is. * for ((param, value) : params) { * ZSTD_CCtx_setParameter(zcs, param, value); * } - * ZSTD_CCtx_setPledgedSrcSize(zcs, pledgedSrcSize); - * ZSTD_CCtx_loadDictionary(zcs, dict, dictSize); - * + * ZSTD_CCtx_setPledgedSrcSize(zcs, pledgedSrcSize); + * ZSTD_CCtx_loadDictionary(zcs, dict, dictSize); + * * dict is loaded with ZSTD_dct_auto and ZSTD_dlm_byCopy. * pledgedSrcSize must be correct. * If srcSize is not known at init time, use value ZSTD_CONTENTSIZE_UNKNOWN. * This prototype will generate compilation warnings. - */ + */ ZSTD_DEPRECATED("use ZSTD_CCtx_reset, see zstd.h for detailed instructions") size_t ZSTD_initCStream_advanced(ZSTD_CStream* zcs, const void* dict, size_t dictSize, @@ -2246,30 +2246,30 @@ size_t ZSTD_initCStream_advanced(ZSTD_CStream* zcs, /*! ZSTD_initCStream_usingCDict() : * This function is DEPRECATED, and equivalent to: - * ZSTD_CCtx_reset(zcs, ZSTD_reset_session_only); - * ZSTD_CCtx_refCDict(zcs, cdict); + * ZSTD_CCtx_reset(zcs, ZSTD_reset_session_only); + * ZSTD_CCtx_refCDict(zcs, cdict); * - * note : cdict will just be referenced, and must outlive compression session + * note : cdict will just be referenced, and must outlive compression session * This prototype will generate compilation warnings. - */ + */ ZSTD_DEPRECATED("use ZSTD_CCtx_reset and ZSTD_CCtx_refCDict, see zstd.h for detailed instructions") size_t ZSTD_initCStream_usingCDict(ZSTD_CStream* zcs, const ZSTD_CDict* cdict); /*! ZSTD_initCStream_usingCDict_advanced() : * This function is DEPRECATED, and is approximately equivalent to: - * ZSTD_CCtx_reset(zcs, ZSTD_reset_session_only); + * ZSTD_CCtx_reset(zcs, ZSTD_reset_session_only); * // Pseudocode: Set each zstd frame parameter and leave the rest as-is. * for ((fParam, value) : fParams) { * ZSTD_CCtx_setParameter(zcs, fParam, value); * } - * ZSTD_CCtx_setPledgedSrcSize(zcs, pledgedSrcSize); - * ZSTD_CCtx_refCDict(zcs, cdict); - * - * same as ZSTD_initCStream_usingCDict(), with control over frame parameters. - * pledgedSrcSize must be correct. If srcSize is not known at init time, use - * value ZSTD_CONTENTSIZE_UNKNOWN. + * ZSTD_CCtx_setPledgedSrcSize(zcs, pledgedSrcSize); + * ZSTD_CCtx_refCDict(zcs, cdict); + * + * same as ZSTD_initCStream_usingCDict(), with control over frame parameters. + * pledgedSrcSize must be correct. If srcSize is not known at init time, use + * value ZSTD_CONTENTSIZE_UNKNOWN. * This prototype will generate compilation warnings. - */ + */ ZSTD_DEPRECATED("use ZSTD_CCtx_reset and ZSTD_CCtx_refCDict, see zstd.h for detailed instructions") size_t ZSTD_initCStream_usingCDict_advanced(ZSTD_CStream* zcs, const ZSTD_CDict* cdict, @@ -2278,91 +2278,91 @@ size_t ZSTD_initCStream_usingCDict_advanced(ZSTD_CStream* zcs, /*! ZSTD_resetCStream() : * This function is DEPRECATED, and is equivalent to: - * ZSTD_CCtx_reset(zcs, ZSTD_reset_session_only); - * ZSTD_CCtx_setPledgedSrcSize(zcs, pledgedSrcSize); + * ZSTD_CCtx_reset(zcs, ZSTD_reset_session_only); + * ZSTD_CCtx_setPledgedSrcSize(zcs, pledgedSrcSize); * Note: ZSTD_resetCStream() interprets pledgedSrcSize == 0 as ZSTD_CONTENTSIZE_UNKNOWN, but * ZSTD_CCtx_setPledgedSrcSize() does not do the same, so ZSTD_CONTENTSIZE_UNKNOWN must be * explicitly specified. - * - * start a new frame, using same parameters from previous frame. - * This is typically useful to skip dictionary loading stage, since it will re-use it in-place. + * + * start a new frame, using same parameters from previous frame. + * This is typically useful to skip dictionary loading stage, since it will re-use it in-place. * Note that zcs must be init at least once before using ZSTD_resetCStream(). * If pledgedSrcSize is not known at reset time, use macro ZSTD_CONTENTSIZE_UNKNOWN. * If pledgedSrcSize > 0, its value must be correct, as it will be written in header, and controlled at the end. * For the time being, pledgedSrcSize==0 is interpreted as "srcSize unknown" for compatibility with older programs, * but it will change to mean "empty" in future version, so use macro ZSTD_CONTENTSIZE_UNKNOWN instead. - * @return : 0, or an error code (which can be tested using ZSTD_isError()) + * @return : 0, or an error code (which can be tested using ZSTD_isError()) * This prototype will generate compilation warnings. - */ + */ ZSTD_DEPRECATED("use ZSTD_CCtx_reset, see zstd.h for detailed instructions") size_t ZSTD_resetCStream(ZSTD_CStream* zcs, unsigned long long pledgedSrcSize); typedef struct { - unsigned long long ingested; /* nb input bytes read and buffered */ - unsigned long long consumed; /* nb input bytes actually compressed */ - unsigned long long produced; /* nb of compressed bytes generated and buffered */ - unsigned long long flushed; /* nb of compressed bytes flushed : not provided; can be tracked from caller side */ - unsigned currentJobID; /* MT only : latest started job nb */ - unsigned nbActiveWorkers; /* MT only : nb of workers actively compressing at probe time */ + unsigned long long ingested; /* nb input bytes read and buffered */ + unsigned long long consumed; /* nb input bytes actually compressed */ + unsigned long long produced; /* nb of compressed bytes generated and buffered */ + unsigned long long flushed; /* nb of compressed bytes flushed : not provided; can be tracked from caller side */ + unsigned currentJobID; /* MT only : latest started job nb */ + unsigned nbActiveWorkers; /* MT only : nb of workers actively compressing at probe time */ } ZSTD_frameProgression; -/* ZSTD_getFrameProgression() : +/* ZSTD_getFrameProgression() : * tells how much data has been ingested (read from input) * consumed (input actually compressed) and produced (output) for current frame. - * Note : (ingested - consumed) is amount of input data buffered internally, not yet compressed. - * Aggregates progression inside active worker threads. + * Note : (ingested - consumed) is amount of input data buffered internally, not yet compressed. + * Aggregates progression inside active worker threads. */ ZSTDLIB_STATIC_API ZSTD_frameProgression ZSTD_getFrameProgression(const ZSTD_CCtx* cctx); -/*! ZSTD_toFlushNow() : - * Tell how many bytes are ready to be flushed immediately. - * Useful for multithreading scenarios (nbWorkers >= 1). - * Probe the oldest active job, defined as oldest job not yet entirely flushed, - * and check its output buffer. - * @return : amount of data stored in oldest job and ready to be flushed immediately. - * if @return == 0, it means either : - * + there is no active job (could be checked with ZSTD_frameProgression()), or - * + oldest job is still actively compressing data, - * but everything it has produced has also been flushed so far, - * therefore flush speed is limited by production speed of oldest job - * irrespective of the speed of concurrent (and newer) jobs. - */ +/*! ZSTD_toFlushNow() : + * Tell how many bytes are ready to be flushed immediately. + * Useful for multithreading scenarios (nbWorkers >= 1). + * Probe the oldest active job, defined as oldest job not yet entirely flushed, + * and check its output buffer. + * @return : amount of data stored in oldest job and ready to be flushed immediately. + * if @return == 0, it means either : + * + there is no active job (could be checked with ZSTD_frameProgression()), or + * + oldest job is still actively compressing data, + * but everything it has produced has also been flushed so far, + * therefore flush speed is limited by production speed of oldest job + * irrespective of the speed of concurrent (and newer) jobs. + */ ZSTDLIB_STATIC_API size_t ZSTD_toFlushNow(ZSTD_CCtx* cctx); /*===== Advanced Streaming decompression functions =====*/ /*! - * This function is deprecated, and is equivalent to: - * - * ZSTD_DCtx_reset(zds, ZSTD_reset_session_only); - * ZSTD_DCtx_loadDictionary(zds, dict, dictSize); - * - * note: no dictionary will be used if dict == NULL or dictSize < 8 + * This function is deprecated, and is equivalent to: + * + * ZSTD_DCtx_reset(zds, ZSTD_reset_session_only); + * ZSTD_DCtx_loadDictionary(zds, dict, dictSize); + * + * note: no dictionary will be used if dict == NULL or dictSize < 8 * Note : this prototype will be marked as deprecated and generate compilation warnings on reaching v1.5.x - */ + */ ZSTDLIB_STATIC_API size_t ZSTD_initDStream_usingDict(ZSTD_DStream* zds, const void* dict, size_t dictSize); /*! - * This function is deprecated, and is equivalent to: - * - * ZSTD_DCtx_reset(zds, ZSTD_reset_session_only); - * ZSTD_DCtx_refDDict(zds, ddict); - * - * note : ddict is referenced, it must outlive decompression session + * This function is deprecated, and is equivalent to: + * + * ZSTD_DCtx_reset(zds, ZSTD_reset_session_only); + * ZSTD_DCtx_refDDict(zds, ddict); + * + * note : ddict is referenced, it must outlive decompression session * Note : this prototype will be marked as deprecated and generate compilation warnings on reaching v1.5.x - */ + */ ZSTDLIB_STATIC_API size_t ZSTD_initDStream_usingDDict(ZSTD_DStream* zds, const ZSTD_DDict* ddict); /*! - * This function is deprecated, and is equivalent to: - * - * ZSTD_DCtx_reset(zds, ZSTD_reset_session_only); - * - * re-use decompression parameters from previous init; saves dictionary loading + * This function is deprecated, and is equivalent to: + * + * ZSTD_DCtx_reset(zds, ZSTD_reset_session_only); + * + * re-use decompression parameters from previous init; saves dictionary loading * Note : this prototype will be marked as deprecated and generate compilation warnings on reaching v1.5.x - */ + */ ZSTDLIB_STATIC_API size_t ZSTD_resetDStream(ZSTD_DStream* zds); @@ -2502,16 +2502,16 @@ typedef struct { unsigned dictID; unsigned checksumFlag; } ZSTD_frameHeader; - + /*! 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() */ + * 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_STATIC_API size_t ZSTD_getFrameHeader(ZSTD_frameHeader* zfhPtr, const void* src, size_t srcSize); /**< doesn't consume input */ -/*! ZSTD_getFrameHeader_advanced() : - * same as ZSTD_getFrameHeader(), - * with added capability to select a format (like ZSTD_f_zstd1_magicless) */ +/*! ZSTD_getFrameHeader_advanced() : + * same as ZSTD_getFrameHeader(), + * with added capability to select a format (like ZSTD_f_zstd1_magicless) */ ZSTDLIB_STATIC_API size_t ZSTD_getFrameHeader_advanced(ZSTD_frameHeader* zfhPtr, const void* src, size_t srcSize, ZSTD_format_e format); ZSTDLIB_STATIC_API size_t ZSTD_decodingBufferSize_min(unsigned long long windowSize, unsigned long long frameContentSize); /**< when frame content size is not known, pass in frameContentSize == ZSTD_CONTENTSIZE_UNKNOWN */ |