From 872bcbc6bc121b89c7d9e7e2d5d0ad64ea775942 Mon Sep 17 00:00:00 2001 From: Turiiya <34311583+ttytm@users.noreply.github.com> Date: Thu, 28 Mar 2024 07:48:27 +0100 Subject: [PATCH] thirdparty: update `zstd` to latest release 1.5.6 (#21124) --- thirdparty/zstd/README.md | 12 +- thirdparty/zstd/zstd.c | 4112 ++++++------------------------------- thirdparty/zstd/zstd.h | 3090 ++++++++++++++++++++++++++++ 3 files changed, 3764 insertions(+), 3450 deletions(-) create mode 100644 thirdparty/zstd/zstd.h diff --git a/thirdparty/zstd/README.md b/thirdparty/zstd/README.md index 189b522183bd60..2e31e9f81c95f7 100644 --- a/thirdparty/zstd/README.md +++ b/thirdparty/zstd/README.md @@ -1,5 +1,7 @@ -Need patch zstd.c: -#if defined(__TINYC__) && defined(_WIN32) -#undef ZSTD_MULTITHREAD -#define ZSTD_NO_INTRINSICS -#endif +zstd.c patch: +```c +#if defined(__TINYC__) && defined(\_WIN32) +#undef ZSTD_MULTITHREAD +#define ZSTD_NO_INTRINSICS +#endif +``` diff --git a/thirdparty/zstd/zstd.c b/thirdparty/zstd/zstd.c index 3b77084ed35dcd..dc53d3b185b69d 100644 --- a/thirdparty/zstd/zstd.c +++ b/thirdparty/zstd/zstd.c @@ -43,7 +43,7 @@ #undef XXH_INLINE_ALL #define XXH_INLINE_ALL #define ZSTD_LEGACY_SUPPORT 0 -#ifndef __EMSCRIPTEN__ +#ifndef __EMSCRIPTEN__ #define ZSTD_MULTITHREAD #endif #define ZSTD_TRACE 0 @@ -289,10 +289,14 @@ extern int g_debuglevel; /* the variable is only declared, } \ } while (0) +#define STRINGIFY(x) #x +#define TOSTRING(x) STRINGIFY(x) +#define LINE_AS_STRING TOSTRING(__LINE__) + # define DEBUGLOG(l, ...) \ do { \ if (l<=g_debuglevel) { \ - ZSTD_DEBUG_PRINT(__FILE__ ": " __VA_ARGS__); \ + ZSTD_DEBUG_PRINT(__FILE__ ":" LINE_AS_STRING ": " __VA_ARGS__); \ ZSTD_DEBUG_PRINT(" \n"); \ } \ } while (0) @@ -4314,3065 +4318,8 @@ int ZSTD_pthread_cond_destroy(ZSTD_pthread_cond_t* cond) /**** skipping file: compiler.h ****/ #define ZSTD_STATIC_LINKING_ONLY -/**** start inlining ../zstd.h ****/ -/* - * Copyright (c) Meta Platforms, Inc. and affiliates. - * All rights reserved. - * - * This source code is licensed under both the BSD-style license (found in the - * LICENSE file in the root directory of this source tree) and the GPLv2 (found - * in the COPYING file in the root directory of this source tree). - * You may select, at your option, one of the above-listed licenses. - */ -#if defined (__cplusplus) -extern "C" { -#endif - -#ifndef ZSTD_H_235446 -#define ZSTD_H_235446 - -/* ====== Dependencies ======*/ -#include /* INT_MAX */ -#include /* size_t */ - - -/* ===== ZSTDLIB_API : control library symbols visibility ===== */ -#ifndef ZSTDLIB_VISIBLE - /* Backwards compatibility with old macro name */ -# ifdef ZSTDLIB_VISIBILITY -# define ZSTDLIB_VISIBLE ZSTDLIB_VISIBILITY -# elif defined(__GNUC__) && (__GNUC__ >= 4) && !defined(__MINGW32__) -# define ZSTDLIB_VISIBLE __attribute__ ((visibility ("default"))) -# else -# define ZSTDLIB_VISIBLE -# endif -#endif - -#ifndef ZSTDLIB_HIDDEN -# if defined(__GNUC__) && (__GNUC__ >= 4) && !defined(__MINGW32__) -# define ZSTDLIB_HIDDEN __attribute__ ((visibility ("hidden"))) -# else -# define ZSTDLIB_HIDDEN -# endif -#endif - -#if defined(ZSTD_DLL_EXPORT) && (ZSTD_DLL_EXPORT==1) -# define ZSTDLIB_API __declspec(dllexport) ZSTDLIB_VISIBLE -#elif defined(ZSTD_DLL_IMPORT) && (ZSTD_DLL_IMPORT==1) -# define ZSTDLIB_API __declspec(dllimport) ZSTDLIB_VISIBLE /* It isn't required but allows to generate better code, saving a function pointer load from the IAT and an indirect jump.*/ -#else -# define ZSTDLIB_API ZSTDLIB_VISIBLE -#endif - -/* Deprecation warnings : - * Should these warnings be a problem, it is generally possible to disable them, - * typically with -Wno-deprecated-declarations for gcc or _CRT_SECURE_NO_WARNINGS in Visual. - * Otherwise, it's also possible to define ZSTD_DISABLE_DEPRECATE_WARNINGS. - */ -#ifdef ZSTD_DISABLE_DEPRECATE_WARNINGS -# define ZSTD_DEPRECATED(message) /* disable deprecation warnings */ -#else -# if defined (__cplusplus) && (__cplusplus >= 201402) /* C++14 or greater */ -# define ZSTD_DEPRECATED(message) [[deprecated(message)]] -# elif (defined(GNUC) && (GNUC > 4 || (GNUC == 4 && GNUC_MINOR >= 5))) || defined(__clang__) -# define ZSTD_DEPRECATED(message) __attribute__((deprecated(message))) -# elif defined(__GNUC__) && (__GNUC__ >= 3) -# define ZSTD_DEPRECATED(message) __attribute__((deprecated)) -# elif defined(_MSC_VER) -# define ZSTD_DEPRECATED(message) __declspec(deprecated(message)) -# else -# pragma message("WARNING: You need to implement ZSTD_DEPRECATED for this compiler") -# define ZSTD_DEPRECATED(message) -# endif -#endif /* ZSTD_DISABLE_DEPRECATE_WARNINGS */ - - -/******************************************************************************* - 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). - - 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: - - a single step (described as Simple 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. -*******************************************************************************/ - -/*------ Version ------*/ -#define ZSTD_VERSION_MAJOR 1 -#define ZSTD_VERSION_MINOR 5 -#define ZSTD_VERSION_RELEASE 5 -#define ZSTD_VERSION_NUMBER (ZSTD_VERSION_MAJOR *100*100 + ZSTD_VERSION_MINOR *100 + ZSTD_VERSION_RELEASE) - -/*! ZSTD_versionNumber() : - * Return runtime library version, the value is (MAJOR*100*100 + MINOR*100 + RELEASE). */ -ZSTDLIB_API unsigned ZSTD_versionNumber(void); - -#define ZSTD_LIB_VERSION ZSTD_VERSION_MAJOR.ZSTD_VERSION_MINOR.ZSTD_VERSION_RELEASE -#define ZSTD_QUOTE(str) #str -#define ZSTD_EXPAND_AND_QUOTE(str) ZSTD_QUOTE(str) -#define ZSTD_VERSION_STRING ZSTD_EXPAND_AND_QUOTE(ZSTD_LIB_VERSION) - -/*! ZSTD_versionString() : - * Return runtime library version, like "1.4.5". Requires v1.3.0+. */ -ZSTDLIB_API const char* ZSTD_versionString(void); - -/* ************************************* - * Default constant - ***************************************/ -#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_compressBound(srcSize)` guarantees that zstd will have - * enough space to successfully compress the data. - * @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_compress( void* dst, size_t dstCapacity, - const void* src, size_t srcSize, - int compressionLevel); - -/*! ZSTD_decompress() : - * `compressedSize` : must be the _exact_ size of some number of compressed and/or skippable frames. - * `dstCapacity` is an upper bound of originalSize to regenerate. - * If user cannot imply a maximum upper bound, it's better to use streaming mode to decompress data. - * @return : the number of bytes decompressed into `dst` (<= `dstCapacity`), - * or an errorCode if it fails (which can be tested using ZSTD_isError()). */ -ZSTDLIB_API size_t ZSTD_decompress( void* dst, size_t dstCapacity, - const void* src, size_t compressedSize); - -/*! 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 - * - 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". - * note 2 : decompressed size is an optional field, it may not be present, typically in streaming mode. - * When `return==ZSTD_CONTENTSIZE_UNKNOWN`, data to decompress could be any size. - * In which case, it's necessary to use streaming mode to decompress data. - * 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 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. - * note 5 : If source is untrusted, decompressed size could be wrong or intentionally modified. - * Always ensure return value fits within application's authorized limits. - * Each application can set its own limits. - * note 6 : This function replaces ZSTD_getDecompressedSize() */ -#define ZSTD_CONTENTSIZE_UNKNOWN (0ULL - 1) -#define ZSTD_CONTENTSIZE_ERROR (0ULL - 2) -ZSTDLIB_API unsigned long long ZSTD_getFrameContentSize(const void *src, size_t srcSize); - -/*! ZSTD_getDecompressedSize() : - * NOTE: This function is now obsolete, in favor of ZSTD_getFrameContentSize(). - * 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. */ -ZSTD_DEPRECATED("Replaced by ZSTD_getFrameContentSize") -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); - - -/*====== Helper functions ======*/ -/* ZSTD_compressBound() : - * maximum compressed size in worst case single-pass scenario. - * When invoking `ZSTD_compress()` or any other one-pass compression function, - * it's recommended to provide @dstCapacity >= ZSTD_compressBound(srcSize) - * as it eliminates one potential failure scenario, - * aka not enough room in dst buffer to write the compressed frame. - * Note : ZSTD_compressBound() itself can fail, if @srcSize > ZSTD_MAX_INPUT_SIZE . - * In which case, ZSTD_compressBound() will return an error code - * which can be tested using ZSTD_isError(). - * - * ZSTD_COMPRESSBOUND() : - * same as ZSTD_compressBound(), but as a macro. - * It can be used to produce constants, which can be useful for static allocation, - * for example to size a static array on stack. - * Will produce constant value 0 if srcSize too large. - */ -#define ZSTD_MAX_INPUT_SIZE ((sizeof(size_t)==8) ? 0xFF00FF00FF00FF00ULL : 0xFF00FF00U) -#define ZSTD_COMPRESSBOUND(srcSize) (((size_t)(srcSize) >= ZSTD_MAX_INPUT_SIZE) ? 0 : (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 */ -/* ZSTD_isError() : - * Most ZSTD_* functions returning a size_t value can be tested for error, - * using ZSTD_isError(). - * @return 1 if error, 0 otherwise - */ -ZSTDLIB_API unsigned ZSTD_isError(size_t code); /*!< tells if a `size_t` function result is an error code */ -ZSTDLIB_API const char* ZSTD_getErrorName(size_t code); /*!< provides readable string from an error code */ -ZSTDLIB_API int ZSTD_minCLevel(void); /*!< minimum negative compression level allowed, requires v1.4.0+ */ -ZSTDLIB_API int ZSTD_maxCLevel(void); /*!< maximum compression level available */ -ZSTDLIB_API int ZSTD_defaultCLevel(void); /*!< default compression level, specified by ZSTD_CLEVEL_DEFAULT, requires v1.5.0+ */ - - -/*************************************** -* Explicit context -***************************************/ -/*= Compression context - * When compressing many times, - * it is recommended to allocate a context just once, - * and reuse it for each successive compression operation. - * This will make workload friendlier for system's memory. - * Note : re-using context is just a speed / resource optimization. - * It doesn't change the compression ratio, which remains identical. - * Note 2 : In multi-threaded environments, - * use one different context per thread for parallel execution. - */ -typedef struct ZSTD_CCtx_s ZSTD_CCtx; -ZSTDLIB_API ZSTD_CCtx* ZSTD_createCCtx(void); -ZSTDLIB_API size_t ZSTD_freeCCtx(ZSTD_CCtx* cctx); /* accept NULL pointer */ - -/*! ZSTD_compressCCtx() : - * Same as ZSTD_compress(), using an explicit ZSTD_CCtx. - * Important : in order to behave similarly to `ZSTD_compress()`, - * this function compresses at requested compression level, - * __ignoring any other parameter__ . - * 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, - void* dst, size_t dstCapacity, - const void* src, size_t srcSize, - int compressionLevel); - -/*= Decompression context - * When decompressing many times, - * it is recommended to allocate a context only once, - * and reuse it for each successive compression operation. - * This will make workload friendlier for system's memory. - * Use one context per thread for parallel execution. */ -typedef struct ZSTD_DCtx_s ZSTD_DCtx; -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, - void* dst, size_t dstCapacity, - const void* src, size_t srcSize); - - -/********************************************* -* 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*()` ! - * __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(). - * - * 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 - * 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. - * 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 - * ones will 'stick'. */ - /* 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. - * 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 - * 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. - * 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. - * 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 - * 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(), - * 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) */ - - /* 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. - * 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, - * 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. - * 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. - * 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_targetCBlockSize - * ZSTD_c_srcSizeHint - * ZSTD_c_enableDedicatedDictSearch - * ZSTD_c_stableInBuffer - * ZSTD_c_stableOutBuffer - * ZSTD_c_blockDelimiters - * ZSTD_c_validateSequences - * ZSTD_c_useBlockSplitter - * ZSTD_c_useRowMatchFinder - * ZSTD_c_prefetchCDictTables - * ZSTD_c_enableSeqProducerFallback - * ZSTD_c_maxBlockSize - * 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, - ZSTD_c_experimentalParam9=1006, - ZSTD_c_experimentalParam10=1007, - ZSTD_c_experimentalParam11=1008, - ZSTD_c_experimentalParam12=1009, - ZSTD_c_experimentalParam13=1010, - ZSTD_c_experimentalParam14=1011, - ZSTD_c_experimentalParam15=1012, - ZSTD_c_experimentalParam16=1013, - ZSTD_c_experimentalParam17=1014, - ZSTD_c_experimentalParam18=1015, - ZSTD_c_experimentalParam19=1016 -} 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 also removes any reference to any dictionary or external sequence producer. - * 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. - * NOTE: Providing `dstCapacity >= ZSTD_compressBound(srcSize)` guarantees that zstd will have - * enough space to successfully compress the data, though it is possible it fails for other reasons. - * @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 : - * ZSTD_d_format - * ZSTD_d_stableOutBuffer - * ZSTD_d_forceIgnoreChecksum - * ZSTD_d_refMultipleDDicts - * ZSTD_d_disableHuffmanAssembly - * ZSTD_d_maxBlockSize - * 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_d_experimentalParam5=1004, - ZSTD_d_experimentalParam6=1005 - -} 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 -****************************/ - -typedef struct ZSTD_inBuffer_s { - const void* src; /**< start of input buffer */ - size_t size; /**< size of input buffer */ - size_t pos; /**< position where reading stopped. Will be updated. Necessarily 0 <= pos <= size */ -} ZSTD_inBuffer; - -typedef struct ZSTD_outBuffer_s { - void* dst; /**< start of output buffer */ - size_t size; /**< size of output buffer */ - size_t pos; /**< position where writing stopped. Will be updated. Necessarily 0 <= pos <= size */ -} ZSTD_outBuffer; - - - -/*-*********************************************************************** -* Streaming compression - HowTo -* -* 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 reuse 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. -* -* note : since v1.3.0, ZSTD_CStream and ZSTD_CCtx are the same thing. -* -* Parameters are sticky : when starting a new compression on the same context, -* it will reuse 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. -* 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. -* @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), -* 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 */ -/*===== 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; - -/*! 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. - * - endOp must be a valid directive - * - 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); - - -/* These buffer sizes are softly recommended. - * They are not required : ZSTD_compressStream*() happily accepts any buffer size, for both input and output. - * Respecting the recommended size just makes it a bit easier for ZSTD_compressStream*(), - * reducing the amount of memory shuffling and buffering, resulting in minor performance savings. - * - * However, note that these recommendations are from the perspective of a C caller program. - * If the streaming interface is invoked from some other language, - * especially managed ones such as Java or Go, through a foreign function interface such as jni or cgo, - * a major performance rule is to reduce crossing such interface to an absolute minimum. - * It's not rare that performance ends being spent more into the interface, rather than compression itself. - * In which cases, prefer using large buffers, as large as practical, - * for both input and output, to reduce the nb of roundtrips. - */ -ZSTDLIB_API size_t ZSTD_CStreamInSize(void); /**< recommended size for input buffer */ -ZSTDLIB_API size_t ZSTD_CStreamOutSize(void); /**< recommended size for output buffer. Guarantee to successfully flush at least one complete compressed block. */ - - -/* ***************************************************************************** - * This following is a legacy streaming API, available since v1.0+ . - * It can be replaced by ZSTD_CCtx_reset() and ZSTD_compressStream2(). - * It is redundant, but remains fully supported. - ******************************************************************************/ - -/*! - * 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); - * - * Note that ZSTD_initCStream() clears any previously set dictionary. Use the new API - * to compress with a dictionary. - */ -ZSTDLIB_API size_t ZSTD_initCStream(ZSTD_CStream* zcs, int compressionLevel); -/*! - * Alternative for ZSTD_compressStream2(zcs, output, input, ZSTD_e_continue). - * NOTE: The return value is different. ZSTD_compressStream() returns a hint for - * the next read size (if non-zero and not an error). ZSTD_compressStream2() - * returns the 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); -/*! Equivalent to ZSTD_compressStream2(zcs, output, &emptyInput, ZSTD_e_end). */ -ZSTDLIB_API size_t ZSTD_endStream(ZSTD_CStream* zcs, ZSTD_outBuffer* output); - - -/*-*************************************************************************** -* Streaming decompression - HowTo -* -* A ZSTD_DStream object is required to track streaming operations. -* Use ZSTD_createDStream() and ZSTD_freeDStream() to create/release resources. -* ZSTD_DStream objects can be reused 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_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. -* 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. -* *******************************************************************************/ - -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. */ -/*===== 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 =====*/ - -/*! ZSTD_initDStream() : - * Initialize/reset DStream state for new decompression operation. - * Call before new decompression operation using same DStream. - * - * Note : This function is redundant with the advanced API and equivalent to: - * ZSTD_DCtx_reset(zds, ZSTD_reset_session_only); - * ZSTD_DCtx_refDDict(zds, NULL); - */ -ZSTDLIB_API size_t ZSTD_initDStream(ZSTD_DStream* zds); - -/*! ZSTD_decompressStream() : - * Streaming decompression function. - * Call repetitively to consume full input updating it as necessary. - * Function will update both input and output `pos` fields exposing current state via these fields: - * - `input.pos < input.size`, some input remaining and caller should provide remaining input - * on the next call. - * - `output.pos < output.size`, decoder finished and flushed all remaining buffers. - * - `output.pos == output.size`, potentially uncflushed data present in the internal buffers, - * call ZSTD_decompressStream() again to flush remaining data to output. - * Note : with no additional input, amount of data flushed <= 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 some decoding or flushing to do to complete current frame. - */ -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), - * 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() : - * 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. - * @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() : - * 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() : - * 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 - *******************************/ - -/*! 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); - -/*! 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. - * Non-conformant dictionaries can still be loaded, but as content-only dictionaries. */ -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); - -/*! 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 piece of 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(), - * ZSTD_compressStream2(), and ZSTD_decompressDCtx(). - * Dictionaries are sticky, they remain valid when same context is reused, - * they only reset when the context is reset - * with ZSTD_reset_parameters or ZSTD_reset_session_and_parameters. - * In contrast, 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, - * until parameters are reset, a new dictionary is loaded, or the dictionary - * is explicitly invalidated by loading a NULL dictionary. - * 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. - * Note 5 : This method does not benefit from LDM (long distance mode). - * If you want to employ LDM on some large dictionary content, - * prefer employing ZSTD_CCtx_refPrefix() described below. - */ -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 future 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); - -/*! 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). - * This method is compatible with LDM (long distance mode). - * @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); - -/*! ZSTD_DCtx_loadDictionary() : Requires v1.4.0+ - * Create an internal DDict from dict buffer, to be used to decompress all future frames. - * The dictionary remains valid for all future frames, until explicitly invalidated, or - * a new dictionary is loaded. - * @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. - * - * 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 - * will be determined at decompression time, as per the dict ID in the frame. - * The memory for the table is allocated on the first call to refDDict, and can be - * freed with ZSTD_freeDCtx(). - * - * If called with ZSTD_d_refMultipleDDicts disabled (the default), only one dictionary - * will be managed, and referencing a dictionary effectively "discards" any previous one. - * - * @result : 0, or an error code (which can be tested with ZSTD_isError()). - * 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. - * 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 === */ - -/*! 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); - -#endif /* ZSTD_H_235446 */ - - -/* ************************************************************************************** - * ADVANCED AND EXPERIMENTAL FUNCTIONS - **************************************************************************************** - * The definitions in the following section are considered experimental. - * They are provided for advanced scenarios. - * They should never be used with a dynamic library, as prototypes may change in the future. - * Use them only in association with static linking. - * ***************************************************************************************/ - -#if defined(ZSTD_STATIC_LINKING_ONLY) && !defined(ZSTD_H_ZSTD_STATIC_LINKING_ONLY) -#define ZSTD_H_ZSTD_STATIC_LINKING_ONLY - -/* This can be overridden externally to hide static symbols. */ -#ifndef ZSTDLIB_STATIC_API -# if defined(ZSTD_DLL_EXPORT) && (ZSTD_DLL_EXPORT==1) -# define ZSTDLIB_STATIC_API __declspec(dllexport) ZSTDLIB_VISIBLE -# elif defined(ZSTD_DLL_IMPORT) && (ZSTD_DLL_IMPORT==1) -# define ZSTDLIB_STATIC_API __declspec(dllimport) ZSTDLIB_VISIBLE -# else -# define ZSTDLIB_STATIC_API ZSTDLIB_VISIBLE -# endif -#endif - -/**************************************************************************************** - * 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_BLOCKSIZE_MAX_MIN (1 << 10) /* The minimum valid max blocksize. Maximum blocksizes smaller than this make compressBound() inaccurate. */ - - -#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< 0: - * If litLength != 0: - * rep == 1 --> offset == repeat_offset_1 - * rep == 2 --> offset == repeat_offset_2 - * rep == 3 --> offset == repeat_offset_3 - * If litLength == 0: - * rep == 1 --> offset == repeat_offset_2 - * rep == 2 --> offset == repeat_offset_3 - * rep == 3 --> offset == repeat_offset_1 - 1 - * - * Note: This field is optional. ZSTD_generateSequences() will calculate the value of - * 'rep', but repeat offsets do not necessarily need to be calculated from an external - * sequence provider's perspective. For example, ZSTD_compressSequences() does not - * use this 'rep' field at all (as of now). - */ -} 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 */ -} 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) */ -} ZSTD_frameParameters; - -typedef struct { - ZSTD_compressionParameters cParams; - ZSTD_frameParameters fParams; -} 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_dictContentType_e; - -typedef enum { - 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) */ - 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; - -typedef enum { - /* Note: this enum controls ZSTD_d_forceIgnoreChecksum */ - ZSTD_d_validateChecksum = 0, - ZSTD_d_ignoreChecksum = 1 -} ZSTD_forceIgnoreChecksum_e; - -typedef enum { - /* Note: this enum controls ZSTD_d_refMultipleDDicts */ - ZSTD_rmd_refSingleDDict = 0, - ZSTD_rmd_refMultipleDDicts = 1 -} 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. - * - * 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 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_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_lcm_uncompressed = 2 /**< Always emit uncompressed literals. */ -} 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 - * or ZSTD_ps_disable allow for a force enable/disable the feature. - */ - ZSTD_ps_auto = 0, /* Let the library automatically determine whether the feature shall be enabled */ - ZSTD_ps_enable = 1, /* Force-enable the feature */ - ZSTD_ps_disable = 2 /* Do not use the feature */ -} ZSTD_paramSwitch_e; - -/*************************************** -* Frame header and size functions -***************************************/ - -/*! ZSTD_findDecompressedSize() : - * `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 : - 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 - * - * note 1 : decompressed size is an optional field, that may not be present, especially in streaming mode. - * When `return==ZSTD_CONTENTSIZE_UNKNOWN`, data to decompress could be any size. - * In which case, it's necessary to use streaming mode to decompress data. - * note 2 : decompressed size is always present when compression is done with ZSTD_compress() - * note 3 : 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. - * note 4 : If source is untrusted, decompressed size could be wrong or intentionally modified. - * Always ensure result fits within application's authorized limits. - * Each application can set its own limits. - * note 5 : ZSTD_findDecompressedSize handles multiple frames, and so it must traverse the input to - * read each contained frame header. This is fast as most of the data is skipped, - * however it does mean that all frame data must be present and valid. */ -ZSTDLIB_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 - * - 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) - */ -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) */ -ZSTDLIB_STATIC_API size_t ZSTD_frameHeaderSize(const void* src, size_t srcSize); - -typedef enum { ZSTD_frame, ZSTD_skippableFrame } ZSTD_frameType_e; -typedef struct { - unsigned long long frameContentSize; /* if == ZSTD_CONTENTSIZE_UNKNOWN, it means this field is not available. 0 means "empty" */ - unsigned long long windowSize; /* can be very large, up to <= frameContentSize */ - unsigned blockSizeMax; - ZSTD_frameType_e frameType; /* if == ZSTD_skippableFrame, frameContentSize is the size of skippable content */ - unsigned headerSize; - unsigned dictID; - unsigned checksumFlag; - unsigned _reserved1; - unsigned _reserved2; -} 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() */ -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) */ -ZSTDLIB_STATIC_API size_t ZSTD_getFrameHeader_advanced(ZSTD_frameHeader* zfhPtr, const void* src, size_t srcSize, ZSTD_format_e format); - -/*! ZSTD_decompressionMargin() : - * Zstd supports in-place decompression, where the input and output buffers overlap. - * In this case, the output buffer must be at least (Margin + Output_Size) bytes large, - * and the input buffer must be at the end of the output buffer. - * - * _______________________ Output Buffer ________________________ - * | | - * | ____ Input Buffer ____| - * | | | - * v v v - * |---------------------------------------|-----------|----------| - * ^ ^ ^ - * |___________________ Output_Size ___________________|_ Margin _| - * - * NOTE: See also ZSTD_DECOMPRESSION_MARGIN(). - * NOTE: This applies only to single-pass decompression through ZSTD_decompress() or - * ZSTD_decompressDCtx(). - * NOTE: This function supports multi-frame input. - * - * @param src The compressed frame(s) - * @param srcSize The size of the compressed frame(s) - * @returns The decompression margin or an error that can be checked with ZSTD_isError(). - */ -ZSTDLIB_STATIC_API size_t ZSTD_decompressionMargin(const void* src, size_t srcSize); - -/*! ZSTD_DECOMPRESS_MARGIN() : - * Similar to ZSTD_decompressionMargin(), but instead of computing the margin from - * the compressed frame, compute it from the original size and the blockSizeLog. - * See ZSTD_decompressionMargin() for details. - * - * WARNING: This macro does not support multi-frame input, the input must be a single - * zstd frame. If you need that support use the function, or implement it yourself. - * - * @param originalSize The original uncompressed size of the data. - * @param blockSize The block size == MIN(windowSize, ZSTD_BLOCKSIZE_MAX). - * Unless you explicitly set the windowLog smaller than - * ZSTD_BLOCKSIZELOG_MAX you can just use ZSTD_BLOCKSIZE_MAX. - */ -#define ZSTD_DECOMPRESSION_MARGIN(originalSize, blockSize) ((size_t)( \ - ZSTD_FRAMEHEADERSIZE_MAX /* Frame header */ + \ - 4 /* checksum */ + \ - ((originalSize) == 0 ? 0 : 3 * (((originalSize) + (blockSize) - 1) / blockSize)) /* 3 bytes per block */ + \ - (blockSize) /* One block of margin */ \ - )) - -typedef enum { - ZSTD_sf_noBlockDelimiters = 0, /* Representation of ZSTD_Sequence has no block delimiters, sequences only */ - ZSTD_sf_explicitBlockDelimiters = 1 /* Representation of ZSTD_Sequence contains explicit block delimiters */ -} ZSTD_sequenceFormat_e; - -/*! ZSTD_sequenceBound() : - * `srcSize` : size of the input buffer - * @return : upper-bound for the number of sequences that can be generated - * from a buffer of srcSize bytes - * - * note : returns number of sequences - to get bytes, multiply by sizeof(ZSTD_Sequence). - */ -ZSTDLIB_STATIC_API size_t ZSTD_sequenceBound(size_t srcSize); - -/*! ZSTD_generateSequences() : - * Generate sequences using ZSTD_compress2(), given a source buffer. - * - * Each block will end with a dummy sequence - * with offset == 0, matchLength == 0, and litLength == length of last literals. - * litLength may be == 0, and if so, then the sequence of (of: 0 ml: 0 ll: 0) - * simply acts as a block delimiter. - * - * @zc can be used to insert custom compression params. - * This function invokes ZSTD_compress2(). - * - * The output of this function can be fed into ZSTD_compressSequences() with CCtx - * setting of ZSTD_c_blockDelimiters as ZSTD_sf_explicitBlockDelimiters - * @return : number of sequences generated - */ - -ZSTDLIB_STATIC_API size_t -ZSTD_generateSequences( ZSTD_CCtx* zc, - ZSTD_Sequence* outSeqs, size_t outSeqsSize, - const void* src, size_t srcSize); - -/*! ZSTD_mergeBlockDelimiters() : - * Given an array of ZSTD_Sequence, remove all sequences that represent block delimiters/last literals - * by merging them into the literals of the next sequence. - * - * As such, the final generated result has no explicit representation of block boundaries, - * and the final last literals segment is not represented in the sequences. - * - * The output of this function can be fed into ZSTD_compressSequences() with CCtx - * setting of ZSTD_c_blockDelimiters as ZSTD_sf_noBlockDelimiters - * @return : number of sequences left after merging - */ -ZSTDLIB_STATIC_API size_t ZSTD_mergeBlockDelimiters(ZSTD_Sequence* sequences, size_t seqsSize); - -/*! ZSTD_compressSequences() : - * Compress an array of ZSTD_Sequence, associated with @src buffer, into dst. - * @src contains the entire input (not just the literals). - * If @srcSize > sum(sequence.length), the remaining bytes are considered all literals - * If a dictionary is included, then the cctx should reference the dict. (see: ZSTD_CCtx_refCDict(), ZSTD_CCtx_loadDictionary(), etc.) - * The entire source is compressed into a single frame. - * - * The compression behavior changes based on cctx params. In particular: - * If ZSTD_c_blockDelimiters == ZSTD_sf_noBlockDelimiters, the array of ZSTD_Sequence is expected to contain - * no block delimiters (defined in ZSTD_Sequence). Block boundaries are roughly determined based on - * the block size derived from the cctx, and sequences may be split. This is the default setting. - * - * If ZSTD_c_blockDelimiters == ZSTD_sf_explicitBlockDelimiters, the array of ZSTD_Sequence is expected to contain - * block delimiters (defined in ZSTD_Sequence). Behavior is undefined if no block delimiters are provided. - * - * If ZSTD_c_validateSequences == 0, this function will blindly accept the sequences provided. Invalid sequences cause undefined - * behavior. If ZSTD_c_validateSequences == 1, then if sequence is invalid (see doc/zstd_compression_format.md for - * specifics regarding offset/matchlength requirements) then the function will bail out and return an error. - * - * In addition to the two adjustable experimental params, there are other important cctx params. - * - ZSTD_c_minMatch MUST be set as less than or equal to the smallest match generated by the match finder. It has a minimum value of ZSTD_MINMATCH_MIN. - * - ZSTD_c_compressionLevel accordingly adjusts the strength of the entropy coder, as it would in typical compression. - * - ZSTD_c_windowLog affects offset validation: this function will return an error at higher debug levels if a provided offset - * is larger than what the spec allows for a given window log and dictionary (if present). See: doc/zstd_compression_format.md - * - * Note: Repcodes are, as of now, always re-calculated within this function, so ZSTD_Sequence::rep is unused. - * Note 2: Once we integrate ability to ingest repcodes, the explicit block delims mode must respect those repcodes exactly, - * and cannot emit an RLE block that disagrees with the repcode history - * @return : final compressed size, or a ZSTD error code. - */ -ZSTDLIB_STATIC_API size_t -ZSTD_compressSequences( ZSTD_CCtx* cctx, void* dst, size_t dstSize, - const ZSTD_Sequence* inSeqs, size_t inSeqsSize, - const void* src, size_t srcSize); - - -/*! ZSTD_writeSkippableFrame() : - * Generates a zstd skippable frame containing data given by src, and writes it to dst buffer. - * - * Skippable frames begin with a 4-byte magic number. There are 16 possible choices of magic number, - * ranging from ZSTD_MAGIC_SKIPPABLE_START to ZSTD_MAGIC_SKIPPABLE_START+15. - * As such, the parameter magicVariant controls the exact skippable frame magic number variant used, so - * the magic number used will be ZSTD_MAGIC_SKIPPABLE_START + magicVariant. - * - * Returns an error if destination buffer is not large enough, if the source size is not representable - * with a 4-byte unsigned int, or if the parameter magicVariant is greater than 15 (and therefore invalid). - * - * @return : number of bytes written or a ZSTD error. - */ -ZSTDLIB_STATIC_API size_t ZSTD_writeSkippableFrame(void* dst, size_t dstCapacity, - const void* src, size_t srcSize, unsigned magicVariant); - -/*! ZSTD_readSkippableFrame() : - * Retrieves a zstd skippable frame containing data given by src, and writes it to dst buffer. - * - * The parameter magicVariant will receive the magicVariant that was supplied when the frame was written, - * i.e. magicNumber - ZSTD_MAGIC_SKIPPABLE_START. This can be NULL if the caller is not interested - * in the magicVariant. - * - * Returns an error if destination buffer is not large enough, or if the frame is not skippable. - * - * @return : number of bytes written or a ZSTD error. - */ -ZSTDLIB_API size_t ZSTD_readSkippableFrame(void* dst, size_t dstCapacity, unsigned* magicVariant, - const void* src, size_t srcSize); - -/*! ZSTD_isSkippableFrame() : - * Tells if the content of `buffer` starts with a valid Frame Identifier for a skippable frame. - */ -ZSTDLIB_API unsigned ZSTD_isSkippableFrame(const void* buffer, size_t size); - - - -/*************************************** -* Memory management -***************************************/ - -/*! ZSTD_estimate*() : - * These functions make it possible to estimate memory usage - * of a future {D,C}Ctx, before its creation. - * This is useful in combination with ZSTD_initStatic(), - * which makes it possible to employ a static buffer for ZSTD_CCtx* state. - * - * ZSTD_estimateCCtxSize() will provide a memory budget large enough - * to compress data of any size using one-shot compression ZSTD_compressCCtx() or ZSTD_compress2() - * associated with any compression level up to max specified one. - * The estimate will assume the input may be arbitrarily large, - * which is the worst case. - * - * Note that the size estimation is specific for one-shot compression, - * it is not valid for streaming (see ZSTD_estimateCStreamSize*()) - * nor other potential ways of using a ZSTD_CCtx* state. - * - * When srcSize can be bound by a known and rather "small" value, - * this knowledge can be used to provide a tighter budget estimation - * because the ZSTD_CCtx* state will need less memory for small inputs. - * This tighter estimation can be provided by employing more advanced functions - * ZSTD_estimateCCtxSize_usingCParams(), which can be used in tandem with ZSTD_getCParams(), - * and ZSTD_estimateCCtxSize_usingCCtxParams(), which can be used in tandem with ZSTD_CCtxParams_setParameter(). - * Both can be used to estimate memory using custom compression parameters and arbitrary srcSize limits. - * - * Note : only single-threaded compression is supported. - * ZSTD_estimateCCtxSize_usingCCtxParams() will return an error code if ZSTD_c_nbWorkers is >= 1. - */ -ZSTDLIB_STATIC_API size_t ZSTD_estimateCCtxSize(int maxCompressionLevel); -ZSTDLIB_STATIC_API size_t ZSTD_estimateCCtxSize_usingCParams(ZSTD_compressionParameters cParams); -ZSTDLIB_STATIC_API size_t ZSTD_estimateCCtxSize_usingCCtxParams(const ZSTD_CCtx_params* params); -ZSTDLIB_STATIC_API size_t ZSTD_estimateDCtxSize(void); - -/*! ZSTD_estimateCStreamSize() : - * ZSTD_estimateCStreamSize() will provide a memory budget large enough for streaming compression - * using any compression level up to the max specified one. - * It will also consider src size to be arbitrarily "large", which is a worst case scenario. - * 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. - * Note : CStream size estimation is only correct for single-threaded compression. - * ZSTD_estimateCStreamSize_usingCCtxParams() will return an error code if ZSTD_c_nbWorkers is >= 1. - * Note 2 : ZSTD_estimateCStreamSize* functions are not compatible with the Block-Level Sequence Producer API at this time. - * Size estimates assume that no external sequence producer is registered. - * - * ZSTD_DStream memory budget depends on frame's window Size. - * This information can be passed manually, using ZSTD_estimateDStreamSize, - * or deducted from a valid frame Header, using ZSTD_estimateDStreamSize_fromFrame(); - * Any frame requesting a window size larger than max specified one will be rejected. - * Note : if streaming is init with function ZSTD_init?Stream_usingDict(), - * an internal ?Dict will be created, which additional size is not estimated here. - * In this case, get total size by adding ZSTD_estimate?DictSize - */ -ZSTDLIB_STATIC_API size_t ZSTD_estimateCStreamSize(int maxCompressionLevel); -ZSTDLIB_STATIC_API size_t ZSTD_estimateCStreamSize_usingCParams(ZSTD_compressionParameters cParams); -ZSTDLIB_STATIC_API size_t ZSTD_estimateCStreamSize_usingCCtxParams(const ZSTD_CCtx_params* params); -ZSTDLIB_STATIC_API size_t ZSTD_estimateDStreamSize(size_t maxWindowSize); -ZSTDLIB_STATIC_API size_t ZSTD_estimateDStreamSize_fromFrame(const void* src, size_t srcSize); - -/*! ZSTD_estimate?DictSize() : - * ZSTD_estimateCDictSize() will bet that src size is relatively "small", and content is copied, like ZSTD_createCDict(). - * ZSTD_estimateCDictSize_advanced() makes it possible to control compression parameters precisely, like ZSTD_createCDict_advanced(). - * Note : dictionaries created by reference (`ZSTD_dlm_byRef`) are logically smaller. - */ -ZSTDLIB_STATIC_API size_t ZSTD_estimateCDictSize(size_t dictSize, int compressionLevel); -ZSTDLIB_STATIC_API size_t ZSTD_estimateCDictSize_advanced(size_t dictSize, ZSTD_compressionParameters cParams, ZSTD_dictLoadMethod_e dictLoadMethod); -ZSTDLIB_STATIC_API size_t ZSTD_estimateDDictSize(size_t dictSize, ZSTD_dictLoadMethod_e dictLoadMethod); - -/*! ZSTD_initStatic*() : - * Initialize an object using a pre-allocated fixed-size buffer. - * workspace: The memory area to emplace the object into. - * Provided pointer *must be 8-bytes aligned*. - * Buffer must outlive object. - * workspaceSize: Use ZSTD_estimate*Size() to determine - * how large workspace must be to support target scenario. - * @return : pointer to object (same address as workspace, just different type), - * or NULL if error (size too small, incorrect alignment, etc.) - * Note : zstd will never resize nor malloc() when using a static buffer. - * If the object requires more memory than available, - * zstd will just error out (typically ZSTD_error_memory_allocation). - * Note 2 : there is no corresponding "free" function. - * Since workspace is allocated externally, it must be freed externally too. - * Note 3 : cParams : use ZSTD_getCParams() to convert a compression level - * into its associated cParams. - * Limitation 1 : currently not compatible with internal dictionary creation, triggered by - * ZSTD_CCtx_loadDictionary(), ZSTD_initCStream_usingDict() or ZSTD_initDStream_usingDict(). - * Limitation 2 : static cctx currently not compatible with multi-threading. - * Limitation 3 : static dctx is incompatible with legacy support. - */ -ZSTDLIB_STATIC_API ZSTD_CCtx* ZSTD_initStaticCCtx(void* workspace, size_t workspaceSize); -ZSTDLIB_STATIC_API ZSTD_CStream* ZSTD_initStaticCStream(void* workspace, size_t workspaceSize); /**< same as ZSTD_initStaticCCtx() */ - -ZSTDLIB_STATIC_API ZSTD_DCtx* ZSTD_initStaticDCtx(void* workspace, size_t workspaceSize); -ZSTDLIB_STATIC_API ZSTD_DStream* ZSTD_initStaticDStream(void* workspace, size_t workspaceSize); /**< same as ZSTD_initStaticDCtx() */ - -ZSTDLIB_STATIC_API const ZSTD_CDict* ZSTD_initStaticCDict( - void* workspace, size_t workspaceSize, - const void* dict, size_t dictSize, - ZSTD_dictLoadMethod_e dictLoadMethod, - ZSTD_dictContentType_e dictContentType, - ZSTD_compressionParameters cParams); - -ZSTDLIB_STATIC_API const ZSTD_DDict* ZSTD_initStaticDDict( - void* workspace, size_t workspaceSize, - const void* dict, size_t dictSize, - 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. - * All allocation/free operations will be completed using these custom variants instead of regular ones. - */ -typedef void* (*ZSTD_allocFunction) (void* opaque, size_t size); -typedef void (*ZSTD_freeFunction) (void* opaque, void* address); -typedef struct { ZSTD_allocFunction customAlloc; ZSTD_freeFunction customFree; void* opaque; } ZSTD_customMem; -static -#ifdef __GNUC__ -__attribute__((__unused__)) -#endif -ZSTD_customMem const ZSTD_defaultCMem = { NULL, NULL, NULL }; /**< this constant defers to stdlib's functions */ - -ZSTDLIB_STATIC_API ZSTD_CCtx* ZSTD_createCCtx_advanced(ZSTD_customMem customMem); -ZSTDLIB_STATIC_API ZSTD_CStream* ZSTD_createCStream_advanced(ZSTD_customMem customMem); -ZSTDLIB_STATIC_API ZSTD_DCtx* ZSTD_createDCtx_advanced(ZSTD_customMem customMem); -ZSTDLIB_STATIC_API ZSTD_DStream* ZSTD_createDStream_advanced(ZSTD_customMem customMem); - -ZSTDLIB_STATIC_API ZSTD_CDict* ZSTD_createCDict_advanced(const void* dict, size_t dictSize, - ZSTD_dictLoadMethod_e dictLoadMethod, - ZSTD_dictContentType_e dictContentType, - ZSTD_compressionParameters cParams, - ZSTD_customMem customMem); - -/*! Thread pool : - * These prototypes make it possible to share a thread pool among multiple compression contexts. - * This can limit resources for applications with multiple threads where each one uses - * a threaded compression mode (via ZSTD_c_nbWorkers parameter). - * ZSTD_createThreadPool creates a new thread pool with a given number of threads. - * Note that the lifetime of such pool must exist while being used. - * ZSTD_CCtx_refThreadPool assigns a thread pool to a context (use NULL argument value - * to use an internal thread pool). - * ZSTD_freeThreadPool frees a thread pool, accepts NULL pointer. - */ -typedef struct POOL_ctx_s ZSTD_threadPool; -ZSTDLIB_STATIC_API ZSTD_threadPool* ZSTD_createThreadPool(size_t numThreads); -ZSTDLIB_STATIC_API void ZSTD_freeThreadPool (ZSTD_threadPool* pool); /* accept NULL pointer */ -ZSTDLIB_STATIC_API size_t ZSTD_CCtx_refThreadPool(ZSTD_CCtx* cctx, ZSTD_threadPool* pool); - - -/* - * This API is temporary and is expected to change or disappear in the future! - */ -ZSTDLIB_STATIC_API ZSTD_CDict* ZSTD_createCDict_advanced2( - const void* dict, size_t dictSize, - ZSTD_dictLoadMethod_e dictLoadMethod, - ZSTD_dictContentType_e dictContentType, - const ZSTD_CCtx_params* cctxParams, - ZSTD_customMem customMem); - -ZSTDLIB_STATIC_API ZSTD_DDict* ZSTD_createDDict_advanced( - const void* dict, size_t dictSize, - ZSTD_dictLoadMethod_e dictLoadMethod, - ZSTD_dictContentType_e dictContentType, - ZSTD_customMem customMem); - - -/*************************************** -* Advanced compression functions -***************************************/ - -/*! ZSTD_createCDict_byReference() : - * Create a digested dictionary for compression - * 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 */ -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 */ -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()) */ -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) */ -ZSTDLIB_STATIC_API ZSTD_compressionParameters ZSTD_adjustCParams(ZSTD_compressionParameters cPar, unsigned long long srcSize, size_t dictSize); - -/*! ZSTD_CCtx_setCParams() : - * Set all parameters provided within @p cparams into the working @p cctx. - * Note : if modifying parameters during compression (MT mode only), - * note that changes to the .windowLog parameter will be ignored. - * @return 0 on success, or an error code (can be checked with ZSTD_isError()). - * On failure, no parameters are updated. - */ -ZSTDLIB_STATIC_API size_t ZSTD_CCtx_setCParams(ZSTD_CCtx* cctx, ZSTD_compressionParameters cparams); - -/*! ZSTD_CCtx_setFParams() : - * Set all parameters provided within @p fparams into the working @p cctx. - * @return 0 on success, or an error code (can be checked with ZSTD_isError()). - */ -ZSTDLIB_STATIC_API size_t ZSTD_CCtx_setFParams(ZSTD_CCtx* cctx, ZSTD_frameParameters fparams); - -/*! ZSTD_CCtx_setParams() : - * Set all parameters provided within @p params into the working @p cctx. - * @return 0 on success, or an error code (can be checked with ZSTD_isError()). - */ -ZSTDLIB_STATIC_API size_t ZSTD_CCtx_setParams(ZSTD_CCtx* cctx, ZSTD_parameters params); - -/*! ZSTD_compress_advanced() : - * Note : this function is now DEPRECATED. - * It can be replaced by ZSTD_compress2(), in combination with ZSTD_CCtx_setParameter() and other parameter setters. - * This prototype will generate compilation warnings. */ -ZSTD_DEPRECATED("use ZSTD_compress2") -ZSTDLIB_STATIC_API -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); - -/*! ZSTD_compress_usingCDict_advanced() : - * Note : this function is now DEPRECATED. - * It can be replaced by ZSTD_compress2(), in combination with ZSTD_CCtx_loadDictionary() and other parameter setters. - * This prototype will generate compilation warnings. */ -ZSTD_DEPRECATED("use ZSTD_compress2 with ZSTD_CCtx_loadDictionary") -ZSTDLIB_STATIC_API -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); - - -/*! 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 ?) */ -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 ?) */ -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 - -/* Controlled with ZSTD_paramSwitch_e enum. - * Default is ZSTD_ps_auto. - * Set to ZSTD_ps_disable to never compress literals. - * Set to ZSTD_ps_enable to always compress literals. (Note: uncompressed literals - * may still be emitted if huffman is not beneficial to use.) - * - * 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 - -/* Tries to fit compressed block size to be around targetCBlockSize. - * No target when targetCBlockSize == 0. - * There is no guarantee on compressed block size (default:0) */ -#define ZSTD_c_targetCBlockSize ZSTD_c_experimentalParam6 - -/* User's best guess of source size. - * Hint is not valid when srcSizeHint == 0. - * There is no guarantee that hint is close to actual source size, - * but compression ratio may regress significantly if guess considerably underestimates */ -#define ZSTD_c_srcSizeHint ZSTD_c_experimentalParam7 - -/* Controls whether the new and experimental "dedicated dictionary search - * structure" can be used. This feature is still rough around the edges, be - * prepared for surprising behavior! - * - * How to use it: - * - * When using a CDict, whether to use this feature or not is controlled at - * CDict creation, and it must be set in a CCtxParams set passed into that - * construction (via ZSTD_createCDict_advanced2()). A compression will then - * use the feature or not based on how the CDict was constructed; the value of - * this param, set in the CCtx, will have no effect. - * - * However, when a dictionary buffer is passed into a CCtx, such as via - * ZSTD_CCtx_loadDictionary(), this param can be set on the CCtx to control - * whether the CDict that is created internally can use the feature or not. - * - * What it does: - * - * Normally, the internal data structures of the CDict are analogous to what - * would be stored in a CCtx after compressing the contents of a dictionary. - * To an approximation, a compression using a dictionary can then use those - * data structures to simply continue what is effectively a streaming - * compression where the simulated compression of the dictionary left off. - * Which is to say, the search structures in the CDict are normally the same - * format as in the CCtx. - * - * It is possible to do better, since the CDict is not like a CCtx: the search - * structures are written once during CDict creation, and then are only read - * after that, while the search structures in the CCtx are both read and - * written as the compression goes along. This means we can choose a search - * structure for the dictionary that is read-optimized. - * - * This feature enables the use of that different structure. - * - * Note that some of the members of the ZSTD_compressionParameters struct have - * different semantics and constraints in the dedicated search structure. It is - * highly recommended that you simply set a compression level in the CCtxParams - * you pass into the CDict creation call, and avoid messing with the cParams - * directly. - * - * Effects: - * - * This will only have any effect when the selected ZSTD_strategy - * implementation supports this feature. Currently, that's limited to - * ZSTD_greedy, ZSTD_lazy, and ZSTD_lazy2. - * - * Note that this means that the CDict tables can no longer be copied into the - * CCtx, so the dict attachment mode ZSTD_dictForceCopy will no longer be - * usable. The dictionary can only be attached or reloaded. - * - * In general, you should expect compression to be faster--sometimes very much - * so--and CDict creation to be slightly slower. Eventually, we will probably - * make this mode the default. - */ -#define ZSTD_c_enableDedicatedDictSearch ZSTD_c_experimentalParam8 - -/* ZSTD_c_stableInBuffer - * Experimental parameter. - * Default is 0 == disabled. Set to 1 to enable. - * - * Tells the compressor that input data presented with ZSTD_inBuffer - * will ALWAYS be the same between calls. - * Technically, the @src pointer must never be changed, - * and the @pos field can only be updated by zstd. - * However, it's possible to increase the @size field, - * allowing scenarios where more data can be appended after compressions starts. - * These conditions are checked by the compressor, - * and compression will fail if they are not respected. - * Also, data in the ZSTD_inBuffer within the range [src, src + pos) - * MUST not be modified during compression or it will result in data corruption. - * - * When this flag is enabled zstd won't allocate an input window buffer, - * because the user guarantees it can reference the ZSTD_inBuffer until - * the frame is complete. But, it will still allocate an output buffer - * large enough to fit a block (see ZSTD_c_stableOutBuffer). This will also - * avoid the memcpy() from the input buffer to the input window buffer. - * - * NOTE: So long as the ZSTD_inBuffer always points to valid memory, using - * this flag is ALWAYS memory safe, and will never access out-of-bounds - * memory. However, compression WILL fail if conditions are not respected. - * - * WARNING: The data in the ZSTD_inBuffer in the range [src, src + pos) MUST - * not be modified during compression or it will result in data corruption. - * This is because zstd needs to reference data in the ZSTD_inBuffer to find - * matches. Normally zstd maintains its own window buffer for this purpose, - * but passing this flag tells zstd to rely on user provided buffer instead. - */ -#define ZSTD_c_stableInBuffer ZSTD_c_experimentalParam9 - -/* ZSTD_c_stableOutBuffer - * Experimental parameter. - * Default is 0 == disabled. Set to 1 to enable. - * - * Tells he compressor that the ZSTD_outBuffer will not be resized between - * calls. Specifically: (out.size - out.pos) will never grow. This gives the - * compressor the freedom to say: If the compressed data doesn't fit in the - * output buffer then return ZSTD_error_dstSizeTooSmall. This allows us to - * always decompress directly into the output buffer, instead of decompressing - * into an internal buffer and copying to the output buffer. - * - * When this flag is enabled zstd won't allocate an output buffer, because - * it can write directly to the ZSTD_outBuffer. It will still allocate the - * input window buffer (see ZSTD_c_stableInBuffer). - * - * Zstd will check that (out.size - out.pos) never grows and return an error - * if it does. While not strictly necessary, this should prevent surprises. - */ -#define ZSTD_c_stableOutBuffer ZSTD_c_experimentalParam10 - -/* ZSTD_c_blockDelimiters - * Default is 0 == ZSTD_sf_noBlockDelimiters. - * - * For use with sequence compression API: ZSTD_compressSequences(). - * - * Designates whether or not the given array of ZSTD_Sequence contains block delimiters - * and last literals, which are defined as sequences with offset == 0 and matchLength == 0. - * See the definition of ZSTD_Sequence for more specifics. - */ -#define ZSTD_c_blockDelimiters ZSTD_c_experimentalParam11 - -/* ZSTD_c_validateSequences - * Default is 0 == disabled. Set to 1 to enable sequence validation. - * - * For use with sequence compression API: ZSTD_compressSequences(). - * Designates whether or not we validate sequences provided to ZSTD_compressSequences() - * during function execution. - * - * Without validation, providing a sequence that does not conform to the zstd spec will cause - * undefined behavior, and may produce a corrupted block. - * - * With validation enabled, if sequence is invalid (see doc/zstd_compression_format.md for - * specifics regarding offset/matchlength requirements) then the function will bail out and - * return an error. - * - */ -#define ZSTD_c_validateSequences ZSTD_c_experimentalParam12 - -/* ZSTD_c_useBlockSplitter - * Controlled with ZSTD_paramSwitch_e enum. - * Default is ZSTD_ps_auto. - * Set to ZSTD_ps_disable to never use block splitter. - * Set to ZSTD_ps_enable to always use block splitter. - * - * By default, in ZSTD_ps_auto, the library will decide at runtime whether to use - * block splitting based on the compression parameters. - */ -#define ZSTD_c_useBlockSplitter ZSTD_c_experimentalParam13 - -/* ZSTD_c_useRowMatchFinder - * Controlled with ZSTD_paramSwitch_e enum. - * Default is ZSTD_ps_auto. - * Set to ZSTD_ps_disable to never use row-based matchfinder. - * Set to ZSTD_ps_enable to force usage of row-based matchfinder. - * - * By default, in ZSTD_ps_auto, the library will decide at runtime whether to use - * the row-based matchfinder based on support for SIMD instructions and the window log. - * Note that this only pertains to compression strategies: greedy, lazy, and lazy2 - */ -#define ZSTD_c_useRowMatchFinder ZSTD_c_experimentalParam14 - -/* ZSTD_c_deterministicRefPrefix - * Default is 0 == disabled. Set to 1 to enable. - * - * Zstd produces different results for prefix compression when the prefix is - * directly adjacent to the data about to be compressed vs. when it isn't. - * This is because zstd detects that the two buffers are contiguous and it can - * use a more efficient match finding algorithm. However, this produces different - * results than when the two buffers are non-contiguous. This flag forces zstd - * to always load the prefix in non-contiguous mode, even if it happens to be - * adjacent to the data, to guarantee determinism. - * - * If you really care about determinism when using a dictionary or prefix, - * like when doing delta compression, you should select this option. It comes - * at a speed penalty of about ~2.5% if the dictionary and data happened to be - * contiguous, and is free if they weren't contiguous. We don't expect that - * intentionally making the dictionary and data contiguous will be worth the - * cost to memcpy() the data. - */ -#define ZSTD_c_deterministicRefPrefix ZSTD_c_experimentalParam15 - -/* ZSTD_c_prefetchCDictTables - * Controlled with ZSTD_paramSwitch_e enum. Default is ZSTD_ps_auto. - * - * In some situations, zstd uses CDict tables in-place rather than copying them - * into the working context. (See docs on ZSTD_dictAttachPref_e above for details). - * In such situations, compression speed is seriously impacted when CDict tables are - * "cold" (outside CPU cache). This parameter instructs zstd to prefetch CDict tables - * when they are used in-place. - * - * For sufficiently small inputs, the cost of the prefetch will outweigh the benefit. - * For sufficiently large inputs, zstd will by default memcpy() CDict tables - * into the working context, so there is no need to prefetch. This parameter is - * targeted at a middle range of input sizes, where a prefetch is cheap enough to be - * useful but memcpy() is too expensive. The exact range of input sizes where this - * makes sense is best determined by careful experimentation. - * - * Note: for this parameter, ZSTD_ps_auto is currently equivalent to ZSTD_ps_disable, - * but in the future zstd may conditionally enable this feature via an auto-detection - * heuristic for cold CDicts. - * Use ZSTD_ps_disable to opt out of prefetching under any circumstances. - */ -#define ZSTD_c_prefetchCDictTables ZSTD_c_experimentalParam16 - -/* ZSTD_c_enableSeqProducerFallback - * Allowed values are 0 (disable) and 1 (enable). The default setting is 0. - * - * Controls whether zstd will fall back to an internal sequence producer if an - * external sequence producer is registered and returns an error code. This fallback - * is block-by-block: the internal sequence producer will only be called for blocks - * where the external sequence producer returns an error code. Fallback parsing will - * follow any other cParam settings, such as compression level, the same as in a - * normal (fully-internal) compression operation. - * - * The user is strongly encouraged to read the full Block-Level Sequence Producer API - * documentation (below) before setting this parameter. */ -#define ZSTD_c_enableSeqProducerFallback ZSTD_c_experimentalParam17 - -/* ZSTD_c_maxBlockSize - * Allowed values are between 1KB and ZSTD_BLOCKSIZE_MAX (128KB). - * The default is ZSTD_BLOCKSIZE_MAX, and setting to 0 will set to the default. - * - * This parameter can be used to set an upper bound on the blocksize - * that overrides the default ZSTD_BLOCKSIZE_MAX. It cannot be used to set upper - * bounds greater than ZSTD_BLOCKSIZE_MAX or bounds lower than 1KB (will make - * compressBound() inaccurate). Only currently meant to be used for testing. - * - */ -#define ZSTD_c_maxBlockSize ZSTD_c_experimentalParam18 - -/* ZSTD_c_searchForExternalRepcodes - * This parameter affects how zstd parses external sequences, such as sequences - * provided through the compressSequences() API or from an external block-level - * sequence producer. - * - * If set to ZSTD_ps_enable, the library will check for repeated offsets in - * external sequences, even if those repcodes are not explicitly indicated in - * the "rep" field. Note that this is the only way to exploit repcode matches - * while using compressSequences() or an external sequence producer, since zstd - * currently ignores the "rep" field of external sequences. - * - * If set to ZSTD_ps_disable, the library will not exploit repeated offsets in - * external sequences, regardless of whether the "rep" field has been set. This - * reduces sequence compression overhead by about 25% while sacrificing some - * compression ratio. - * - * The default value is ZSTD_ps_auto, for which the library will enable/disable - * based on compression level. - * - * Note: for now, this param only has an effect if ZSTD_c_blockDelimiters is - * set to ZSTD_sf_explicitBlockDelimiters. That may change in the future. - */ -#define ZSTD_c_searchForExternalRepcodes ZSTD_c_experimentalParam19 - -/*! 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_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. - */ -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. - */ -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. - */ -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. - */ -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. - * 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()). - */ -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). - */ -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. - */ -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_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. - * Note 2 : Legacy Frame Identifiers are considered valid only if Legacy Support is enabled. - * Note 3 : Skippable Frame Identifiers are considered valid. */ -ZSTDLIB_STATIC_API unsigned ZSTD_isFrame(const void* buffer, size_t size); - -/*! ZSTD_createDDict_byReference() : - * Create a digested dictionary, ready to start decompression operation without startup delay. - * Dictionary content is referenced, and therefore stays in dictBuffer. - * It is important that dictBuffer outlives DDict, - * 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. */ -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 ?). */ -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 ?) */ -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()). - */ -ZSTDLIB_STATIC_API size_t ZSTD_DCtx_setMaxWindowSize(ZSTD_DCtx* dctx, size_t maxWindowSize); - -/*! ZSTD_DCtx_getParameter() : - * Get the requested decompression parameter value, selected by enum ZSTD_dParameter, - * 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_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_stableOutBuffer - * Experimental parameter. - * Default is 0 == disabled. Set to 1 to enable. - * - * Tells the decompressor that the ZSTD_outBuffer will ALWAYS be the same - * between calls, except for the modifications that zstd makes to pos (the - * caller must not modify pos). This is checked by the decompressor, and - * decompression will fail if it ever changes. Therefore the ZSTD_outBuffer - * MUST be large enough to fit the entire decompressed frame. This will be - * checked when the frame content size is known. The data in the ZSTD_outBuffer - * in the range [dst, dst + pos) MUST not be modified during decompression - * or you will get data corruption. - * - * When this flag is enabled zstd won't allocate an output buffer, because - * it can write directly to the ZSTD_outBuffer, but it will still allocate - * an input buffer large enough to fit any compressed block. This will also - * avoid the memcpy() from the internal output buffer to the ZSTD_outBuffer. - * If you need to avoid the input buffer allocation use the buffer-less - * streaming API. - * - * NOTE: So long as the ZSTD_outBuffer always points to valid memory, using - * this flag is ALWAYS memory safe, and will never access out-of-bounds - * memory. However, decompression WILL fail if you violate the preconditions. - * - * WARNING: The data in the ZSTD_outBuffer in the range [dst, dst + pos) MUST - * not be modified during decompression or you will get data corruption. This - * is because zstd needs to reference data in the ZSTD_outBuffer to regenerate - * matches. Normally zstd maintains its own buffer for this purpose, but passing - * this flag tells zstd to use the user provided buffer. - */ -#define ZSTD_d_stableOutBuffer ZSTD_d_experimentalParam2 - -/* ZSTD_d_forceIgnoreChecksum - * Experimental parameter. - * Default is 0 == disabled. Set to 1 to enable - * - * Tells the decompressor to skip checksum validation during decompression, regardless - * of whether checksumming was specified during compression. This offers some - * slight performance benefits, and may be useful for debugging. - * Param has values of type ZSTD_forceIgnoreChecksum_e - */ -#define ZSTD_d_forceIgnoreChecksum ZSTD_d_experimentalParam3 - -/* ZSTD_d_refMultipleDDicts - * Experimental parameter. - * Default is 0 == disabled. Set to 1 to enable - * - * If enabled and dctx is allocated on the heap, then additional memory will be allocated - * to store references to multiple ZSTD_DDict. That is, multiple calls of ZSTD_refDDict() - * using a given ZSTD_DCtx, rather than overwriting the previous DDict reference, will instead - * store all references. At decompression time, the appropriate dictID is selected - * from the set of DDicts based on the dictID in the frame. - * - * Usage is simply calling ZSTD_refDDict() on multiple dict buffers. - * - * Param has values of byte ZSTD_refMultipleDDicts_e - * - * WARNING: Enabling this parameter and calling ZSTD_DCtx_refDDict(), will trigger memory - * allocation for the hash table. ZSTD_freeDCtx() also frees this memory. - * Memory is allocated as per ZSTD_DCtx::customMem. - * - * Although this function allocates memory for the table, the user is still responsible for - * memory management of the underlying ZSTD_DDict* themselves. - */ -#define ZSTD_d_refMultipleDDicts ZSTD_d_experimentalParam4 - -/* ZSTD_d_disableHuffmanAssembly - * Set to 1 to disable the Huffman assembly implementation. - * The default value is 0, which allows zstd to use the Huffman assembly - * implementation if available. - * - * This parameter can be used to disable Huffman assembly at runtime. - * If you want to disable it at compile time you can define the macro - * ZSTD_DISABLE_ASM. - */ -#define ZSTD_d_disableHuffmanAssembly ZSTD_d_experimentalParam5 - -/* ZSTD_d_maxBlockSize - * Allowed values are between 1KB and ZSTD_BLOCKSIZE_MAX (128KB). - * The default is ZSTD_BLOCKSIZE_MAX, and setting to 0 will set to the default. - * - * Forces the decompressor to reject blocks whose content size is - * larger than the configured maxBlockSize. When maxBlockSize is - * larger than the windowSize, the windowSize is used instead. - * This saves memory on the decoder when you know all blocks are small. - * - * This option is typically used in conjunction with ZSTD_c_maxBlockSize. - * - * WARNING: This causes the decoder to reject otherwise valid frames - * that have block sizes larger than the configured maxBlockSize. - */ -#define ZSTD_d_maxBlockSize ZSTD_d_experimentalParam6 - - -/*! 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()). */ -ZSTD_DEPRECATED("use ZSTD_DCtx_setParameter() instead") -ZSTDLIB_STATIC_API -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. - */ -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); - - -/******************************************************************** -* 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. -********************************************************************/ - -/*===== 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. - * This prototype will generate compilation warnings. - */ -ZSTD_DEPRECATED("use ZSTD_CCtx_reset, see zstd.h for detailed instructions") -ZSTDLIB_STATIC_API -size_t ZSTD_initCStream_srcSize(ZSTD_CStream* zcs, - int compressionLevel, - unsigned long long pledgedSrcSize); - -/*! 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. - * 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. - * This prototype will generate compilation warnings. - */ -ZSTD_DEPRECATED("use ZSTD_CCtx_reset, see zstd.h for detailed instructions") -ZSTDLIB_STATIC_API -size_t ZSTD_initCStream_usingDict(ZSTD_CStream* zcs, - const void* dict, size_t dictSize, - int compressionLevel); - -/*! ZSTD_initCStream_advanced() : - * This function is DEPRECATED, and is equivalent to: - * ZSTD_CCtx_reset(zcs, ZSTD_reset_session_only); - * ZSTD_CCtx_setParams(zcs, params); - * 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") -ZSTDLIB_STATIC_API -size_t ZSTD_initCStream_advanced(ZSTD_CStream* zcs, - const void* dict, size_t dictSize, - ZSTD_parameters params, - unsigned long long pledgedSrcSize); - -/*! ZSTD_initCStream_usingCDict() : - * This function is DEPRECATED, and equivalent to: - * ZSTD_CCtx_reset(zcs, ZSTD_reset_session_only); - * ZSTD_CCtx_refCDict(zcs, cdict); - * - * 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") -ZSTDLIB_STATIC_API -size_t ZSTD_initCStream_usingCDict(ZSTD_CStream* zcs, const ZSTD_CDict* cdict); - -/*! ZSTD_initCStream_usingCDict_advanced() : - * This function is DEPRECATED, and is equivalent to: - * ZSTD_CCtx_reset(zcs, ZSTD_reset_session_only); - * ZSTD_CCtx_setFParams(zcs, fParams); - * 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") -ZSTDLIB_STATIC_API -size_t ZSTD_initCStream_usingCDict_advanced(ZSTD_CStream* zcs, - const ZSTD_CDict* cdict, - ZSTD_frameParameters fParams, - unsigned long long pledgedSrcSize); - -/*! ZSTD_resetCStream() : - * This function is DEPRECATED, and is equivalent to: - * 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 reuse 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()) - * This prototype will generate compilation warnings. - */ -ZSTD_DEPRECATED("use ZSTD_CCtx_reset, see zstd.h for detailed instructions") -ZSTDLIB_STATIC_API -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 */ -} ZSTD_frameProgression; - -/* 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. - */ -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. - */ -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 - */ -ZSTD_DEPRECATED("use ZSTD_DCtx_reset + ZSTD_DCtx_loadDictionary, see zstd.h for detailed instructions") -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 - */ -ZSTD_DEPRECATED("use ZSTD_DCtx_reset + ZSTD_DCtx_refDDict, see zstd.h for detailed instructions") -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); - * - * reuse decompression parameters from previous init; saves dictionary loading - */ -ZSTD_DEPRECATED("use ZSTD_DCtx_reset, see zstd.h for detailed instructions") -ZSTDLIB_STATIC_API size_t ZSTD_resetDStream(ZSTD_DStream* zds); - - -/* ********************* BLOCK-LEVEL SEQUENCE PRODUCER API ********************* - * - * *** OVERVIEW *** - * The Block-Level Sequence Producer API allows users to provide their own custom - * sequence producer which libzstd invokes to process each block. The produced list - * of sequences (literals and matches) is then post-processed by libzstd to produce - * valid compressed blocks. - * - * This block-level offload API is a more granular complement of the existing - * frame-level offload API compressSequences() (introduced in v1.5.1). It offers - * an easier migration story for applications already integrated with libzstd: the - * user application continues to invoke the same compression functions - * ZSTD_compress2() or ZSTD_compressStream2() as usual, and transparently benefits - * from the specific advantages of the external sequence producer. For example, - * the sequence producer could be tuned to take advantage of known characteristics - * of the input, to offer better speed / ratio, or could leverage hardware - * acceleration not available within libzstd itself. - * - * See contrib/externalSequenceProducer for an example program employing the - * Block-Level Sequence Producer API. - * - * *** USAGE *** - * The user is responsible for implementing a function of type - * ZSTD_sequenceProducer_F. For each block, zstd will pass the following - * arguments to the user-provided function: - * - * - sequenceProducerState: a pointer to a user-managed state for the sequence - * producer. - * - * - outSeqs, outSeqsCapacity: an output buffer for the sequence producer. - * outSeqsCapacity is guaranteed >= ZSTD_sequenceBound(srcSize). The memory - * backing outSeqs is managed by the CCtx. - * - * - src, srcSize: an input buffer for the sequence producer to parse. - * srcSize is guaranteed to be <= ZSTD_BLOCKSIZE_MAX. - * - * - dict, dictSize: a history buffer, which may be empty, which the sequence - * producer may reference as it parses the src buffer. Currently, zstd will - * always pass dictSize == 0 into external sequence producers, but this will - * change in the future. - * - * - compressionLevel: a signed integer representing the zstd compression level - * set by the user for the current operation. The sequence producer may choose - * to use this information to change its compression strategy and speed/ratio - * tradeoff. Note: the compression level does not reflect zstd parameters set - * through the advanced API. - * - * - windowSize: a size_t representing the maximum allowed offset for external - * sequences. Note that sequence offsets are sometimes allowed to exceed the - * windowSize if a dictionary is present, see doc/zstd_compression_format.md - * for details. - * - * The user-provided function shall return a size_t representing the number of - * sequences written to outSeqs. This return value will be treated as an error - * code if it is greater than outSeqsCapacity. The return value must be non-zero - * if srcSize is non-zero. The ZSTD_SEQUENCE_PRODUCER_ERROR macro is provided - * for convenience, but any value greater than outSeqsCapacity will be treated as - * an error code. - * - * If the user-provided function does not return an error code, the sequences - * written to outSeqs must be a valid parse of the src buffer. Data corruption may - * occur if the parse is not valid. A parse is defined to be valid if the - * following conditions hold: - * - The sum of matchLengths and literalLengths must equal srcSize. - * - All sequences in the parse, except for the final sequence, must have - * matchLength >= ZSTD_MINMATCH_MIN. The final sequence must have - * matchLength >= ZSTD_MINMATCH_MIN or matchLength == 0. - * - All offsets must respect the windowSize parameter as specified in - * doc/zstd_compression_format.md. - * - If the final sequence has matchLength == 0, it must also have offset == 0. - * - * zstd will only validate these conditions (and fail compression if they do not - * hold) if the ZSTD_c_validateSequences cParam is enabled. Note that sequence - * validation has a performance cost. - * - * If the user-provided function returns an error, zstd will either fall back - * to an internal sequence producer or fail the compression operation. The user can - * choose between the two behaviors by setting the ZSTD_c_enableSeqProducerFallback - * cParam. Fallback compression will follow any other cParam settings, such as - * compression level, the same as in a normal compression operation. - * - * The user shall instruct zstd to use a particular ZSTD_sequenceProducer_F - * function by calling - * ZSTD_registerSequenceProducer(cctx, - * sequenceProducerState, - * sequenceProducer) - * This setting will persist until the next parameter reset of the CCtx. - * - * The sequenceProducerState must be initialized by the user before calling - * ZSTD_registerSequenceProducer(). The user is responsible for destroying the - * sequenceProducerState. - * - * *** LIMITATIONS *** - * This API is compatible with all zstd compression APIs which respect advanced parameters. - * However, there are three limitations: - * - * First, the ZSTD_c_enableLongDistanceMatching cParam is not currently supported. - * COMPRESSION WILL FAIL if it is enabled and the user tries to compress with a block-level - * external sequence producer. - * - Note that ZSTD_c_enableLongDistanceMatching is auto-enabled by default in some - * cases (see its documentation for details). Users must explicitly set - * ZSTD_c_enableLongDistanceMatching to ZSTD_ps_disable in such cases if an external - * sequence producer is registered. - * - As of this writing, ZSTD_c_enableLongDistanceMatching is disabled by default - * whenever ZSTD_c_windowLog < 128MB, but that's subject to change. Users should - * check the docs on ZSTD_c_enableLongDistanceMatching whenever the Block-Level Sequence - * Producer API is used in conjunction with advanced settings (like ZSTD_c_windowLog). - * - * Second, history buffers are not currently supported. Concretely, zstd will always pass - * dictSize == 0 to the external sequence producer (for now). This has two implications: - * - Dictionaries are not currently supported. Compression will *not* fail if the user - * references a dictionary, but the dictionary won't have any effect. - * - Stream history is not currently supported. All advanced compression APIs, including - * streaming APIs, work with external sequence producers, but each block is treated as - * an independent chunk without history from previous blocks. - * - * Third, multi-threading within a single compression is not currently supported. In other words, - * COMPRESSION WILL FAIL if ZSTD_c_nbWorkers > 0 and an external sequence producer is registered. - * Multi-threading across compressions is fine: simply create one CCtx per thread. - * - * Long-term, we plan to overcome all three limitations. There is no technical blocker to - * overcoming them. It is purely a question of engineering effort. - */ - -#define ZSTD_SEQUENCE_PRODUCER_ERROR ((size_t)(-1)) - -typedef size_t (*ZSTD_sequenceProducer_F) ( - void* sequenceProducerState, - ZSTD_Sequence* outSeqs, size_t outSeqsCapacity, - const void* src, size_t srcSize, - const void* dict, size_t dictSize, - int compressionLevel, - size_t windowSize -); - -/*! ZSTD_registerSequenceProducer() : - * Instruct zstd to use a block-level external sequence producer function. - * - * The sequenceProducerState must be initialized by the caller, and the caller is - * responsible for managing its lifetime. This parameter is sticky across - * compressions. It will remain set until the user explicitly resets compression - * parameters. - * - * Sequence producer registration is considered to be an "advanced parameter", - * part of the "advanced API". This means it will only have an effect on compression - * APIs which respect advanced parameters, such as compress2() and compressStream2(). - * Older compression APIs such as compressCCtx(), which predate the introduction of - * "advanced parameters", will ignore any external sequence producer setting. - * - * The sequence producer can be "cleared" by registering a NULL function pointer. This - * removes all limitations described above in the "LIMITATIONS" section of the API docs. - * - * The user is strongly encouraged to read the full API documentation (above) before - * calling this function. */ -ZSTDLIB_STATIC_API void -ZSTD_registerSequenceProducer( - ZSTD_CCtx* cctx, - void* sequenceProducerState, - ZSTD_sequenceProducer_F sequenceProducer -); - -/*! ZSTD_CCtxParams_registerSequenceProducer() : - * Same as ZSTD_registerSequenceProducer(), but operates on ZSTD_CCtx_params. - * This is used for accurate size estimation with ZSTD_estimateCCtxSize_usingCCtxParams(), - * which is needed when creating a ZSTD_CCtx with ZSTD_initStaticCCtx(). - * - * If you are using the external sequence producer API in a scenario where ZSTD_initStaticCCtx() - * is required, then this function is for you. Otherwise, you probably don't need it. - * - * See tests/zstreamtest.c for example usage. */ -ZSTDLIB_STATIC_API void -ZSTD_CCtxParams_registerSequenceProducer( - ZSTD_CCtx_params* params, - void* sequenceProducerState, - ZSTD_sequenceProducer_F sequenceProducer -); - - -/********************************************************************* -* Buffer-less and synchronous inner streaming functions (DEPRECATED) -* -* This API is deprecated, and will be removed in a future version. -* It allows streaming (de)compression with user allocated buffers. -* However, it is hard to use, and not as well tested as the rest of -* our API. -* -* Please use the normal streaming API instead: ZSTD_compressStream2, -* and ZSTD_decompressStream. -* If there is functionality that you need, but it doesn't provide, -* please open an issue on our GitHub. -********************************************************************* */ - -/** - Buffer-less streaming compression (synchronous mode) - - A ZSTD_CCtx object is required to track streaming operations. - Use ZSTD_createCCtx() / ZSTD_freeCCtx() to manage resource. - ZSTD_CCtx object can be reused multiple times within successive compression operations. - - Start by initializing a context. - Use ZSTD_compressBegin(), or ZSTD_compressBegin_usingDict() for dictionary compression. - - Then, consume your input using ZSTD_compressContinue(). - There are some important considerations to keep in mind when using this advanced function : - - ZSTD_compressContinue() has no internal buffer. It uses externally provided buffers only. - - Interface is synchronous : input is consumed entirely and produces 1+ compressed blocks. - - Caller must ensure there is enough space in `dst` to store compressed data under worst case scenario. - Worst case evaluation is provided by ZSTD_compressBound(). - ZSTD_compressContinue() doesn't guarantee recover after a failed compression. - - ZSTD_compressContinue() presumes prior input ***is still accessible and unmodified*** (up to maximum distance size, see WindowLog). - It remembers all previous contiguous blocks, plus one separated memory segment (which can itself consists of multiple contiguous blocks) - - ZSTD_compressContinue() detects that prior input has been overwritten when `src` buffer overlaps. - In which case, it will "discard" the relevant memory section from its history. - - Finish a frame with ZSTD_compressEnd(), which will write the last block(s) and optional checksum. - It's possible to use srcSize==0, in which case, it will write a final empty block to end the frame. - Without last block mark, frames are considered unfinished (hence corrupted) by compliant decoders. - - `ZSTD_CCtx` object can be reused (ZSTD_compressBegin()) to compress again. -*/ - -/*===== Buffer-less streaming compression functions =====*/ -ZSTD_DEPRECATED("The buffer-less API is deprecated in favor of the normal streaming API. See docs.") -ZSTDLIB_STATIC_API size_t ZSTD_compressBegin(ZSTD_CCtx* cctx, int compressionLevel); -ZSTD_DEPRECATED("The buffer-less API is deprecated in favor of the normal streaming API. See docs.") -ZSTDLIB_STATIC_API size_t ZSTD_compressBegin_usingDict(ZSTD_CCtx* cctx, const void* dict, size_t dictSize, int compressionLevel); -ZSTD_DEPRECATED("The buffer-less API is deprecated in favor of the normal streaming API. See docs.") -ZSTDLIB_STATIC_API size_t ZSTD_compressBegin_usingCDict(ZSTD_CCtx* cctx, const ZSTD_CDict* cdict); /**< note: fails if cdict==NULL */ - -ZSTD_DEPRECATED("This function will likely be removed in a future release. It is misleading and has very limited utility.") -ZSTDLIB_STATIC_API -size_t ZSTD_copyCCtx(ZSTD_CCtx* cctx, const ZSTD_CCtx* preparedCCtx, unsigned long long pledgedSrcSize); /**< note: if pledgedSrcSize is not known, use ZSTD_CONTENTSIZE_UNKNOWN */ - -ZSTD_DEPRECATED("The buffer-less API is deprecated in favor of the normal streaming API. See docs.") -ZSTDLIB_STATIC_API size_t ZSTD_compressContinue(ZSTD_CCtx* cctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize); -ZSTD_DEPRECATED("The buffer-less API is deprecated in favor of the normal streaming API. See docs.") -ZSTDLIB_STATIC_API size_t ZSTD_compressEnd(ZSTD_CCtx* cctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize); - -/* The ZSTD_compressBegin_advanced() and ZSTD_compressBegin_usingCDict_advanced() are now DEPRECATED and will generate a compiler warning */ -ZSTD_DEPRECATED("use advanced API to access custom parameters") -ZSTDLIB_STATIC_API -size_t ZSTD_compressBegin_advanced(ZSTD_CCtx* cctx, const void* dict, size_t dictSize, ZSTD_parameters params, unsigned long long pledgedSrcSize); /**< pledgedSrcSize : If srcSize is not known at init time, use ZSTD_CONTENTSIZE_UNKNOWN */ -ZSTD_DEPRECATED("use advanced API to access custom parameters") -ZSTDLIB_STATIC_API -size_t ZSTD_compressBegin_usingCDict_advanced(ZSTD_CCtx* const cctx, const ZSTD_CDict* const cdict, ZSTD_frameParameters const fParams, unsigned long long const pledgedSrcSize); /* compression parameters are already set within cdict. pledgedSrcSize must be correct. If srcSize is not known, use macro ZSTD_CONTENTSIZE_UNKNOWN */ -/** - Buffer-less streaming decompression (synchronous mode) - - A ZSTD_DCtx object is required to track streaming operations. - Use ZSTD_createDCtx() / ZSTD_freeDCtx() to manage it. - A ZSTD_DCtx object can be reused multiple times. - - First typical operation is to retrieve frame parameters, using ZSTD_getFrameHeader(). - Frame header is extracted from the beginning of compressed frame, so providing only the frame's beginning is enough. - Data fragment must be large enough to ensure successful decoding. - `ZSTD_frameHeaderSize_max` bytes is guaranteed to always be large enough. - result : 0 : successful decoding, the `ZSTD_frameHeader` structure is correctly filled. - >0 : `srcSize` is too small, please provide at least result bytes on next attempt. - errorCode, which can be tested using ZSTD_isError(). - - It fills a ZSTD_frameHeader structure with important information to correctly decode the frame, - such as the dictionary ID, content size, or maximum back-reference distance (`windowSize`). - Note that these values could be wrong, either because of data corruption, or because a 3rd party deliberately spoofs false information. - As a consequence, check that values remain within valid application range. - For example, do not allocate memory blindly, check that `windowSize` is within expectation. - Each application can set its own limits, depending on local restrictions. - For extended interoperability, it is recommended to support `windowSize` of at least 8 MB. - - ZSTD_decompressContinue() needs previous data blocks during decompression, up to `windowSize` bytes. - ZSTD_decompressContinue() is very sensitive to contiguity, - if 2 blocks don't follow each other, make sure that either the compressor breaks contiguity at the same place, - or that previous contiguous segment is large enough to properly handle maximum back-reference distance. - There are multiple ways to guarantee this condition. - - The most memory efficient way is to use a round buffer of sufficient size. - Sufficient size is determined by invoking ZSTD_decodingBufferSize_min(), - which can return an error code if required value is too large for current system (in 32-bits mode). - In a round buffer methodology, ZSTD_decompressContinue() decompresses each block next to previous one, - up to the moment there is not enough room left in the buffer to guarantee decoding another full block, - which maximum size is provided in `ZSTD_frameHeader` structure, field `blockSizeMax`. - At which point, decoding can resume from the beginning of the buffer. - Note that already decoded data stored in the buffer should be flushed before being overwritten. - - There are alternatives possible, for example using two or more buffers of size `windowSize` each, though they consume more memory. - - Finally, if you control the compression process, you can also ignore all buffer size rules, - as long as the encoder and decoder progress in "lock-step", - aka use exactly the same buffer sizes, break contiguity at the same place, etc. - - Once buffers are setup, start decompression, with ZSTD_decompressBegin(). - If decompression requires a dictionary, use ZSTD_decompressBegin_usingDict() or ZSTD_decompressBegin_usingDDict(). - - Then use ZSTD_nextSrcSizeToDecompress() and ZSTD_decompressContinue() alternatively. - ZSTD_nextSrcSizeToDecompress() tells how many bytes to provide as 'srcSize' to ZSTD_decompressContinue(). - ZSTD_decompressContinue() requires this _exact_ amount of bytes, or it will fail. - - result of ZSTD_decompressContinue() is the number of bytes regenerated within 'dst' (necessarily <= dstCapacity). - It can be zero : it just means ZSTD_decompressContinue() has decoded some metadata item. - It can also be an error code, which can be tested with ZSTD_isError(). - - A frame is fully decoded when ZSTD_nextSrcSizeToDecompress() returns zero. - Context can then be reset to start a new decompression. - - Note : it's possible to know if next input to present is a header or a block, using ZSTD_nextInputType(). - This information is not required to properly decode a frame. - - == Special case : skippable frames == - - Skippable frames allow integration of user-defined data into a flow of concatenated frames. - Skippable frames will be ignored (skipped) by decompressor. - The format of skippable frames is as follows : - a) Skippable frame ID - 4 Bytes, Little endian format, any value from 0x184D2A50 to 0x184D2A5F - b) Frame Size - 4 Bytes, Little endian format, unsigned 32-bits - c) Frame Content - any content (User Data) of length equal to Frame Size - For skippable frames ZSTD_getFrameHeader() returns zfhPtr->frameType==ZSTD_skippableFrame. - For skippable frames ZSTD_decompressContinue() always returns 0 : it only skips the content. -*/ - -/*===== Buffer-less streaming decompression functions =====*/ - -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 */ - -ZSTDLIB_STATIC_API size_t ZSTD_decompressBegin(ZSTD_DCtx* dctx); -ZSTDLIB_STATIC_API size_t ZSTD_decompressBegin_usingDict(ZSTD_DCtx* dctx, const void* dict, size_t dictSize); -ZSTDLIB_STATIC_API size_t ZSTD_decompressBegin_usingDDict(ZSTD_DCtx* dctx, const ZSTD_DDict* ddict); - -ZSTDLIB_STATIC_API size_t ZSTD_nextSrcSizeToDecompress(ZSTD_DCtx* dctx); -ZSTDLIB_STATIC_API size_t ZSTD_decompressContinue(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize); - -/* misc */ -ZSTD_DEPRECATED("This function will likely be removed in the next minor release. It is misleading and has very limited utility.") -ZSTDLIB_STATIC_API void ZSTD_copyDCtx(ZSTD_DCtx* dctx, const ZSTD_DCtx* preparedDCtx); -typedef enum { ZSTDnit_frameHeader, ZSTDnit_blockHeader, ZSTDnit_block, ZSTDnit_lastBlock, ZSTDnit_checksum, ZSTDnit_skippableFrame } ZSTD_nextInputType_e; -ZSTDLIB_STATIC_API ZSTD_nextInputType_e ZSTD_nextInputType(ZSTD_DCtx* dctx); - - - - -/* ========================================= */ -/** Block level API (DEPRECATED) */ -/* ========================================= */ - -/*! - - This API is deprecated in favor of the regular compression API. - You can get the frame header down to 2 bytes by setting: - - ZSTD_c_format = ZSTD_f_zstd1_magicless - - ZSTD_c_contentSizeFlag = 0 - - ZSTD_c_checksumFlag = 0 - - ZSTD_c_dictIDFlag = 0 - - This API is not as well tested as our normal API, so we recommend not using it. - We will be removing it in a future version. If the normal API doesn't provide - the functionality you need, please open a GitHub issue. - - Block functions produce and decode raw zstd blocks, without frame metadata. - Frame metadata cost is typically ~12 bytes, which can be non-negligible for very small blocks (< 100 bytes). - But users will have to take in charge needed metadata to regenerate data, such as compressed and content sizes. - - A few rules to respect : - - Compressing and decompressing require a context structure - + Use ZSTD_createCCtx() and ZSTD_createDCtx() - - It is necessary to init context before starting - + compression : any ZSTD_compressBegin*() variant, including with dictionary - + decompression : any ZSTD_decompressBegin*() variant, including with dictionary - - Block size is limited, it must be <= ZSTD_getBlockSize() <= ZSTD_BLOCKSIZE_MAX == 128 KB - + If input is larger than a block size, it's necessary to split input data into multiple blocks - + For inputs larger than a single block, consider using regular ZSTD_compress() instead. - Frame metadata is not that costly, and quickly becomes negligible as source size grows larger than a block. - - When a block is considered not compressible enough, ZSTD_compressBlock() result will be 0 (zero) ! - ===> In which case, nothing is produced into `dst` ! - + User __must__ test for such outcome and deal directly with uncompressed data - + A block cannot be declared incompressible if ZSTD_compressBlock() return value was != 0. - Doing so would mess up with statistics history, leading to potential data corruption. - + ZSTD_decompressBlock() _doesn't accept uncompressed data as input_ !! - + In case of multiple successive blocks, should some of them be uncompressed, - decoder must be informed of their existence in order to follow proper history. - Use ZSTD_insertBlock() for such a case. -*/ - -/*===== Raw zstd block functions =====*/ -ZSTD_DEPRECATED("The block API is deprecated in favor of the normal compression API. See docs.") -ZSTDLIB_STATIC_API size_t ZSTD_getBlockSize (const ZSTD_CCtx* cctx); -ZSTD_DEPRECATED("The block API is deprecated in favor of the normal compression API. See docs.") -ZSTDLIB_STATIC_API size_t ZSTD_compressBlock (ZSTD_CCtx* cctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize); -ZSTD_DEPRECATED("The block API is deprecated in favor of the normal compression API. See docs.") -ZSTDLIB_STATIC_API size_t ZSTD_decompressBlock(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize); -ZSTD_DEPRECATED("The block API is deprecated in favor of the normal compression API. See docs.") -ZSTDLIB_STATIC_API size_t ZSTD_insertBlock (ZSTD_DCtx* dctx, const void* blockStart, size_t blockSize); /**< insert uncompressed block into `dctx` history. Useful for multi-blocks decompression. */ - -#endif /* ZSTD_H_ZSTD_STATIC_LINKING_ONLY */ - -#if defined (__cplusplus) -} -#endif -/**** ended inlining ../zstd.h ****/ +/**** *NOT* inlining ../zstd.h ****/ +#include "zstd.h" /* ZSTD_customMem */ #ifndef ZSTD_ALLOCATIONS_H #define ZSTD_ALLOCATIONS_H @@ -7939,6 +4886,7 @@ MEM_STATIC ZSTD_cpuid_t ZSTD_cpuid(void) { U32 f7b = 0; U32 f7c = 0; #if defined(_MSC_VER) && (defined(_M_X64) || defined(_M_IX86)) +#if !defined(__clang__) int reg[4]; __cpuid((int*)reg, 0); { @@ -7954,6 +4902,41 @@ MEM_STATIC ZSTD_cpuid_t ZSTD_cpuid(void) { f7c = (U32)reg[2]; } } +#else + /* Clang compiler has a bug (fixed in https://reviews.llvm.org/D101338) in + * which the `__cpuid` intrinsic does not save and restore `rbx` as it needs + * to due to being a reserved register. So in that case, do the `cpuid` + * ourselves. Clang supports inline assembly anyway. + */ + U32 n; + __asm__( + "pushq %%rbx\n\t" + "cpuid\n\t" + "popq %%rbx\n\t" + : "=a"(n) + : "a"(0) + : "rcx", "rdx"); + if (n >= 1) { + U32 f1a; + __asm__( + "pushq %%rbx\n\t" + "cpuid\n\t" + "popq %%rbx\n\t" + : "=a"(f1a), "=c"(f1c), "=d"(f1d) + : "a"(1) + :); + } + if (n >= 7) { + __asm__( + "pushq %%rbx\n\t" + "cpuid\n\t" + "movq %%rbx, %%rax\n\t" + "popq %%rbx" + : "=a"(f7b), "=c"(f7c) + : "a"(7), "c"(0) + : "rdx"); + } +#endif #elif defined(__i386__) && defined(__PIC__) && !defined(__clang__) && defined(__GNUC__) /* The following block like the normal cpuid branch below, but gcc * reserves ebx for use of its pic register so we must specially @@ -8705,7 +5688,11 @@ typedef uint32_t XXH32_hash_t; #elif !defined (__VMS) \ && (defined (__cplusplus) \ || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */) ) -# include +# ifdef _AIX +# include +# else +# include +# endif typedef uint32_t XXH32_hash_t; #else @@ -8760,7 +5747,6 @@ XXH_PUBLIC_API XXH_PUREF XXH32_hash_t XXH32 (const void* input, size_t length, X * @brief The opaque state struct for the XXH32 streaming API. * * @see XXH32_state_s for details. - * @see @ref streaming_example "Streaming Example" */ typedef struct XXH32_state_s XXH32_state_t; @@ -8771,8 +5757,6 @@ typedef struct XXH32_state_s XXH32_state_t; * @return `NULL` on failure. * * @note Must be freed with XXH32_freeState(). - * - * @see @ref streaming_example "Streaming Example" */ XXH_PUBLIC_API XXH_MALLOCF XXH32_state_t* XXH32_createState(void); /*! @@ -8784,8 +5768,6 @@ XXH_PUBLIC_API XXH_MALLOCF XXH32_state_t* XXH32_createState(void); * * @note @p statePtr must be allocated with XXH32_createState(). * - * @see @ref streaming_example "Streaming Example" - * */ XXH_PUBLIC_API XXH_errorcode XXH32_freeState(XXH32_state_t* statePtr); /*! @@ -8811,8 +5793,6 @@ XXH_PUBLIC_API void XXH32_copyState(XXH32_state_t* dst_state, const XXH32_state_ * @return @ref XXH_ERROR on failure. * * @note This function resets and seeds a state. Call it before @ref XXH32_update(). - * - * @see @ref streaming_example "Streaming Example" */ XXH_PUBLIC_API XXH_errorcode XXH32_reset (XXH32_state_t* statePtr, XXH32_hash_t seed); @@ -8834,8 +5814,6 @@ XXH_PUBLIC_API XXH_errorcode XXH32_reset (XXH32_state_t* statePtr, XXH32_hash_t * @return @ref XXH_ERROR on failure. * * @note Call this to incrementally consume blocks of data. - * - * @see @ref streaming_example "Streaming Example" */ XXH_PUBLIC_API XXH_errorcode XXH32_update (XXH32_state_t* statePtr, const void* input, size_t length); @@ -8852,8 +5830,6 @@ XXH_PUBLIC_API XXH_errorcode XXH32_update (XXH32_state_t* statePtr, const void* * @note * Calling XXH32_digest() will not affect @p statePtr, so you can update, * digest, and update again. - * - * @see @ref streaming_example "Streaming Example" */ XXH_PUBLIC_API XXH_PUREF XXH32_hash_t XXH32_digest (const XXH32_state_t* statePtr); #endif /* !XXH_NO_STREAM */ @@ -8979,7 +5955,11 @@ typedef uint64_t XXH64_hash_t; #elif !defined (__VMS) \ && (defined (__cplusplus) \ || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */) ) -# include +# ifdef _AIX +# include +# else +# include +# endif typedef uint64_t XXH64_hash_t; #else # include @@ -9030,7 +6010,6 @@ XXH_PUBLIC_API XXH_PUREF XXH64_hash_t XXH64(XXH_NOESCAPE const void* input, size * @brief The opaque state struct for the XXH64 streaming API. * * @see XXH64_state_s for details. - * @see @ref streaming_example "Streaming Example" */ typedef struct XXH64_state_s XXH64_state_t; /* incomplete type */ @@ -9041,8 +6020,6 @@ typedef struct XXH64_state_s XXH64_state_t; /* incomplete type */ * @return `NULL` on failure. * * @note Must be freed with XXH64_freeState(). - * - * @see @ref streaming_example "Streaming Example" */ XXH_PUBLIC_API XXH_MALLOCF XXH64_state_t* XXH64_createState(void); @@ -9054,8 +6031,6 @@ XXH_PUBLIC_API XXH_MALLOCF XXH64_state_t* XXH64_createState(void); * @return @ref XXH_OK. * * @note @p statePtr must be allocated with XXH64_createState(). - * - * @see @ref streaming_example "Streaming Example" */ XXH_PUBLIC_API XXH_errorcode XXH64_freeState(XXH64_state_t* statePtr); @@ -9082,8 +6057,6 @@ XXH_PUBLIC_API void XXH64_copyState(XXH_NOESCAPE XXH64_state_t* dst_state, const * @return @ref XXH_ERROR on failure. * * @note This function resets and seeds a state. Call it before @ref XXH64_update(). - * - * @see @ref streaming_example "Streaming Example" */ XXH_PUBLIC_API XXH_errorcode XXH64_reset (XXH_NOESCAPE XXH64_state_t* statePtr, XXH64_hash_t seed); @@ -9105,8 +6078,6 @@ XXH_PUBLIC_API XXH_errorcode XXH64_reset (XXH_NOESCAPE XXH64_state_t* statePtr, * @return @ref XXH_ERROR on failure. * * @note Call this to incrementally consume blocks of data. - * - * @see @ref streaming_example "Streaming Example" */ XXH_PUBLIC_API XXH_errorcode XXH64_update (XXH_NOESCAPE XXH64_state_t* statePtr, XXH_NOESCAPE const void* input, size_t length); @@ -9123,8 +6094,6 @@ XXH_PUBLIC_API XXH_errorcode XXH64_update (XXH_NOESCAPE XXH64_state_t* statePtr, * @note * Calling XXH64_digest() will not affect @p statePtr, so you can update, * digest, and update again. - * - * @see @ref streaming_example "Streaming Example" */ XXH_PUBLIC_API XXH_PUREF XXH64_hash_t XXH64_digest (XXH_NOESCAPE const XXH64_state_t* statePtr); #endif /* !XXH_NO_STREAM */ @@ -9329,7 +6298,6 @@ XXH_PUBLIC_API XXH_PUREF XXH64_hash_t XXH3_64bits_withSecret(XXH_NOESCAPE const * @brief The opaque state struct for the XXH3 streaming API. * * @see XXH3_state_s for details. - * @see @ref streaming_example "Streaming Example" */ typedef struct XXH3_state_s XXH3_state_t; XXH_PUBLIC_API XXH_MALLOCF XXH3_state_t* XXH3_createState(void); @@ -9361,8 +6329,6 @@ XXH_PUBLIC_API void XXH3_copyState(XXH_NOESCAPE XXH3_state_t* dst_state, XXH_NOE * - Call this function before @ref XXH3_64bits_update(). * - Digest will be equivalent to `XXH3_64bits()`. * - * @see @ref streaming_example "Streaming Example" - * */ XXH_PUBLIC_API XXH_errorcode XXH3_64bits_reset(XXH_NOESCAPE XXH3_state_t* statePtr); @@ -9383,8 +6349,6 @@ XXH_PUBLIC_API XXH_errorcode XXH3_64bits_reset(XXH_NOESCAPE XXH3_state_t* stateP * - Call this function before @ref XXH3_64bits_update(). * - Digest will be equivalent to `XXH3_64bits_withSeed()`. * - * @see @ref streaming_example "Streaming Example" - * */ XXH_PUBLIC_API XXH_errorcode XXH3_64bits_reset_withSeed(XXH_NOESCAPE XXH3_state_t* statePtr, XXH64_hash_t seed); @@ -9409,8 +6373,6 @@ XXH_PUBLIC_API XXH_errorcode XXH3_64bits_reset_withSeed(XXH_NOESCAPE XXH3_state_ * (secret's content should look like a bunch of random bytes). * When in doubt about the randomness of a candidate `secret`, * consider employing `XXH3_generateSecret()` instead (see below). - * - * @see @ref streaming_example "Streaming Example" */ XXH_PUBLIC_API XXH_errorcode XXH3_64bits_reset_withSecret(XXH_NOESCAPE XXH3_state_t* statePtr, XXH_NOESCAPE const void* secret, size_t secretSize); @@ -9432,8 +6394,6 @@ XXH_PUBLIC_API XXH_errorcode XXH3_64bits_reset_withSecret(XXH_NOESCAPE XXH3_stat * @return @ref XXH_ERROR on failure. * * @note Call this to incrementally consume blocks of data. - * - * @see @ref streaming_example "Streaming Example" */ XXH_PUBLIC_API XXH_errorcode XXH3_64bits_update (XXH_NOESCAPE XXH3_state_t* statePtr, XXH_NOESCAPE const void* input, size_t length); @@ -9450,8 +6410,6 @@ XXH_PUBLIC_API XXH_errorcode XXH3_64bits_update (XXH_NOESCAPE XXH3_state_t* stat * @note * Calling XXH3_64bits_digest() will not affect @p statePtr, so you can update, * digest, and update again. - * - * @see @ref streaming_example "Streaming Example" */ XXH_PUBLIC_API XXH_PUREF XXH64_hash_t XXH3_64bits_digest (XXH_NOESCAPE const XXH3_state_t* statePtr); #endif /* !XXH_NO_STREAM */ @@ -9572,8 +6530,6 @@ XXH_PUBLIC_API XXH_PUREF XXH128_hash_t XXH3_128bits_withSecret(XXH_NOESCAPE cons * - This function resets `statePtr` and generate a secret with default parameters. * - Call it before @ref XXH3_128bits_update(). * - Digest will be equivalent to `XXH3_128bits()`. - * - * @see @ref streaming_example "Streaming Example" */ XXH_PUBLIC_API XXH_errorcode XXH3_128bits_reset(XXH_NOESCAPE XXH3_state_t* statePtr); @@ -9593,8 +6549,6 @@ XXH_PUBLIC_API XXH_errorcode XXH3_128bits_reset(XXH_NOESCAPE XXH3_state_t* state * - This function resets `statePtr` and generate a secret from `seed`. * - Call it before @ref XXH3_128bits_update(). * - Digest will be equivalent to `XXH3_128bits_withSeed()`. - * - * @see @ref streaming_example "Streaming Example" */ XXH_PUBLIC_API XXH_errorcode XXH3_128bits_reset_withSeed(XXH_NOESCAPE XXH3_state_t* statePtr, XXH64_hash_t seed); /*! @@ -9616,8 +6570,6 @@ XXH_PUBLIC_API XXH_errorcode XXH3_128bits_reset_withSeed(XXH_NOESCAPE XXH3_state * (secret's content should look like a bunch of random bytes). * When in doubt about the randomness of a candidate `secret`, * consider employing `XXH3_generateSecret()` instead (see below). - * - * @see @ref streaming_example "Streaming Example" */ XXH_PUBLIC_API XXH_errorcode XXH3_128bits_reset_withSecret(XXH_NOESCAPE XXH3_state_t* statePtr, XXH_NOESCAPE const void* secret, size_t secretSize); @@ -10595,7 +7547,11 @@ static void* XXH_memcpy(void* dest, const void* src, size_t size) #if !defined (__VMS) \ && (defined (__cplusplus) \ || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */) ) -# include +# ifdef _AIX +# include +# else +# include +# endif typedef uint8_t xxh_u8; #else typedef unsigned char xxh_u8; @@ -11486,6 +8442,23 @@ static xxh_u64 XXH64_round(xxh_u64 acc, xxh_u64 input) acc += input * XXH_PRIME64_2; acc = XXH_rotl64(acc, 31); acc *= XXH_PRIME64_1; +#if (defined(__AVX512F__)) && !defined(XXH_ENABLE_AUTOVECTORIZE) + /* + * DISABLE AUTOVECTORIZATION: + * A compiler fence is used to prevent GCC and Clang from + * autovectorizing the XXH64 loop (pragmas and attributes don't work for some + * reason) without globally disabling AVX512. + * + * Autovectorization of XXH64 tends to be detrimental, + * though the exact outcome may change depending on exact cpu and compiler version. + * For information, it has been reported as detrimental for Skylake-X, + * but possibly beneficial for Zen4. + * + * The default is to disable auto-vectorization, + * but you can select to enable it instead using `XXH_ENABLE_AUTOVECTORIZE` build variable. + */ + XXH_COMPILER_GUARD(acc); +#endif return acc; } @@ -14202,8 +11175,6 @@ static void XXH_alignedFree(void* p) * @return `NULL` on failure. * * @note Must be freed with XXH3_freeState(). - * - * @see @ref streaming_example "Streaming Example" */ XXH_PUBLIC_API XXH3_state_t* XXH3_createState(void) { @@ -14222,8 +11193,6 @@ XXH_PUBLIC_API XXH3_state_t* XXH3_createState(void) * @return @ref XXH_OK. * * @note Must be allocated with XXH3_createState(). - * - * @see @ref streaming_example "Streaming Example" */ XXH_PUBLIC_API XXH_errorcode XXH3_freeState(XXH3_state_t* statePtr) { @@ -17668,12 +14637,12 @@ HUF_compress1X_usingCTable_internal_body(void* dst, size_t dstSize, const BYTE* ip = (const BYTE*) src; BYTE* const ostart = (BYTE*)dst; BYTE* const oend = ostart + dstSize; - BYTE* op = ostart; HUF_CStream_t bitC; /* init */ if (dstSize < 8) return 0; /* not enough space to compress */ - { size_t const initErr = HUF_initCStream(&bitC, op, (size_t)(oend-op)); + { BYTE* op = ostart; + size_t const initErr = HUF_initCStream(&bitC, op, (size_t)(oend-op)); if (HUF_isError(initErr)) return 0; } if (dstSize < HUF_tightCompressBound(srcSize, (size_t)tableLog) || tableLog > 11) @@ -17894,7 +14863,7 @@ unsigned HUF_optimalTableLog( { BYTE* dst = (BYTE*)workSpace + sizeof(HUF_WriteCTableWksp); size_t dstSize = wkspSize - sizeof(HUF_WriteCTableWksp); - size_t maxBits, hSize, newSize; + size_t hSize, newSize; const unsigned symbolCardinality = HUF_cardinality(count, maxSymbolValue); const unsigned minTableLog = HUF_minTableLog(symbolCardinality); size_t optSize = ((size_t) ~0) - 1; @@ -17905,12 +14874,14 @@ unsigned HUF_optimalTableLog( /* Search until size increases */ for (optLogGuess = minTableLog; optLogGuess <= maxTableLog; optLogGuess++) { DEBUGLOG(7, "checking for huffLog=%u", optLogGuess); - maxBits = HUF_buildCTable_wksp(table, count, maxSymbolValue, optLogGuess, workSpace, wkspSize); - if (ERR_isError(maxBits)) continue; - if (maxBits < optLogGuess && optLogGuess > minTableLog) break; + { size_t maxBits = HUF_buildCTable_wksp(table, count, maxSymbolValue, optLogGuess, workSpace, wkspSize); + if (ERR_isError(maxBits)) continue; - hSize = HUF_writeCTable_wksp(dst, dstSize, table, maxSymbolValue, (U32)maxBits, workSpace, wkspSize); + if (maxBits < optLogGuess && optLogGuess > minTableLog) break; + + hSize = HUF_writeCTable_wksp(dst, dstSize, table, maxSymbolValue, (U32)maxBits, workSpace, wkspSize); + } if (ERR_isError(hSize)) continue; @@ -19120,23 +16091,24 @@ typedef struct { UNUSED_ATTR static const rawSeqStore_t kNullRawSeqStore = {NULL, 0, 0, 0, 0}; typedef struct { - int price; - U32 off; - U32 mlen; - U32 litlen; - U32 rep[ZSTD_REP_NUM]; + int price; /* price from beginning of segment to this position */ + U32 off; /* offset of previous match */ + U32 mlen; /* length of previous match */ + U32 litlen; /* nb of literals since previous match */ + U32 rep[ZSTD_REP_NUM]; /* offset history after previous match */ } ZSTD_optimal_t; typedef enum { zop_dynamic=0, zop_predef } ZSTD_OptPrice_e; +#define ZSTD_OPT_SIZE (ZSTD_OPT_NUM+3) typedef struct { /* All tables are allocated inside cctx->workspace by ZSTD_resetCCtx_internal() */ unsigned* litFreq; /* table of literals statistics, of size 256 */ unsigned* litLengthFreq; /* table of litLength statistics, of size (MaxLL+1) */ unsigned* matchLengthFreq; /* table of matchLength statistics, of size (MaxML+1) */ unsigned* offCodeFreq; /* table of offCode statistics, of size (MaxOff+1) */ - ZSTD_match_t* matchTable; /* list of found matches, of size ZSTD_OPT_NUM+1 */ - ZSTD_optimal_t* priceTable; /* All positions tracked by optimal parser, of size ZSTD_OPT_NUM+1 */ + ZSTD_match_t* matchTable; /* list of found matches, of size ZSTD_OPT_SIZE */ + ZSTD_optimal_t* priceTable; /* All positions tracked by optimal parser, of size ZSTD_OPT_SIZE */ U32 litSum; /* nb of literals */ U32 litLengthSum; /* nb of litLength codes */ @@ -21352,8 +18324,8 @@ ZSTD_compressSubBlock_literal(const HUF_CElt* hufTable, } { int const flags = bmi2 ? HUF_flags_bmi2 : 0; - const size_t cSize = singleStream ? HUF_compress1X_usingCTable(op, oend-op, literals, litSize, hufTable, flags) - : HUF_compress4X_usingCTable(op, oend-op, literals, litSize, hufTable, flags); + const size_t cSize = singleStream ? HUF_compress1X_usingCTable(op, (size_t)(oend-op), literals, litSize, hufTable, flags) + : HUF_compress4X_usingCTable(op, (size_t)(oend-op), literals, litSize, hufTable, flags); op += cSize; cLitSize += cSize; if (cSize == 0 || ERR_isError(cSize)) { @@ -21378,7 +18350,7 @@ ZSTD_compressSubBlock_literal(const HUF_CElt* hufTable, switch(lhSize) { case 3: /* 2 - 2 - 10 - 10 */ - { U32 const lhc = hType + ((!singleStream) << 2) + ((U32)litSize<<4) + ((U32)cLitSize<<14); + { U32 const lhc = hType + ((U32)(!singleStream) << 2) + ((U32)litSize<<4) + ((U32)cLitSize<<14); MEM_writeLE24(ostart, lhc); break; } @@ -21398,30 +18370,30 @@ ZSTD_compressSubBlock_literal(const HUF_CElt* hufTable, } *entropyWritten = 1; DEBUGLOG(5, "Compressed literals: %u -> %u", (U32)litSize, (U32)(op-ostart)); - return op-ostart; + return (size_t)(op-ostart); } static size_t ZSTD_seqDecompressedSize(seqStore_t const* seqStore, - const seqDef* sequences, size_t nbSeq, - size_t litSize, int lastSequence) + const seqDef* sequences, size_t nbSeqs, + size_t litSize, int lastSubBlock) { - const seqDef* const sstart = sequences; - const seqDef* const send = sequences + nbSeq; - const seqDef* sp = sstart; size_t matchLengthSum = 0; size_t litLengthSum = 0; - (void)(litLengthSum); /* suppress unused variable warning on some environments */ - while (send-sp > 0) { - ZSTD_sequenceLength const seqLen = ZSTD_getSequenceLength(seqStore, sp); + size_t n; + for (n=0; nmatchlengthCTable, mlCode, fseTables->offcodeCTable, ofCode, fseTables->litlengthCTable, llCode, @@ -21529,7 +18501,7 @@ ZSTD_compressSubBlock_sequences(const ZSTD_fseCTables_t* fseTables, #endif *entropyWritten = 1; - return op - ostart; + return (size_t)(op - ostart); } /** ZSTD_compressSubBlock() : @@ -21555,7 +18527,8 @@ static size_t ZSTD_compressSubBlock(const ZSTD_entropyCTables_t* entropy, litSize, nbSeq, writeLitEntropy, writeSeqEntropy, lastBlock); { size_t cLitSize = ZSTD_compressSubBlock_literal((const HUF_CElt*)entropy->huf.CTable, &entropyMetadata->hufMetadata, literals, litSize, - op, oend-op, bmi2, writeLitEntropy, litEntropyWritten); + op, (size_t)(oend-op), + bmi2, writeLitEntropy, litEntropyWritten); FORWARD_IF_ERROR(cLitSize, "ZSTD_compressSubBlock_literal failed"); if (cLitSize == 0) return 0; op += cLitSize; @@ -21565,18 +18538,18 @@ static size_t ZSTD_compressSubBlock(const ZSTD_entropyCTables_t* entropy, sequences, nbSeq, llCode, mlCode, ofCode, cctxParams, - op, oend-op, + op, (size_t)(oend-op), bmi2, writeSeqEntropy, seqEntropyWritten); FORWARD_IF_ERROR(cSeqSize, "ZSTD_compressSubBlock_sequences failed"); if (cSeqSize == 0) return 0; op += cSeqSize; } /* Write block header */ - { size_t cSize = (op-ostart)-ZSTD_blockHeaderSize; + { size_t cSize = (size_t)(op-ostart) - ZSTD_blockHeaderSize; U32 const cBlockHeader24 = lastBlock + (((U32)bt_compressed)<<1) + (U32)(cSize << 3); MEM_writeLE24(ostart, cBlockHeader24); } - return op-ostart; + return (size_t)(op-ostart); } static size_t ZSTD_estimateSubBlockSize_literal(const BYTE* literals, size_t litSize, @@ -21665,7 +18638,11 @@ static size_t ZSTD_estimateSubBlockSize_sequences(const BYTE* ofCodeTable, return cSeqSizeEstimate + sequencesSectionHeaderSize; } -static size_t ZSTD_estimateSubBlockSize(const BYTE* literals, size_t litSize, +typedef struct { + size_t estLitSize; + size_t estBlockSize; +} EstimatedBlockSize; +static EstimatedBlockSize ZSTD_estimateSubBlockSize(const BYTE* literals, size_t litSize, const BYTE* ofCodeTable, const BYTE* llCodeTable, const BYTE* mlCodeTable, @@ -21673,15 +18650,17 @@ static size_t ZSTD_estimateSubBlockSize(const BYTE* literals, size_t litSize, const ZSTD_entropyCTables_t* entropy, const ZSTD_entropyCTablesMetadata_t* entropyMetadata, void* workspace, size_t wkspSize, - int writeLitEntropy, int writeSeqEntropy) { - size_t cSizeEstimate = 0; - cSizeEstimate += ZSTD_estimateSubBlockSize_literal(literals, litSize, - &entropy->huf, &entropyMetadata->hufMetadata, - workspace, wkspSize, writeLitEntropy); - cSizeEstimate += ZSTD_estimateSubBlockSize_sequences(ofCodeTable, llCodeTable, mlCodeTable, + int writeLitEntropy, int writeSeqEntropy) +{ + EstimatedBlockSize ebs; + ebs.estLitSize = ZSTD_estimateSubBlockSize_literal(literals, litSize, + &entropy->huf, &entropyMetadata->hufMetadata, + workspace, wkspSize, writeLitEntropy); + ebs.estBlockSize = ZSTD_estimateSubBlockSize_sequences(ofCodeTable, llCodeTable, mlCodeTable, nbSeq, &entropy->fse, &entropyMetadata->fseMetadata, workspace, wkspSize, writeSeqEntropy); - return cSizeEstimate + ZSTD_blockHeaderSize; + ebs.estBlockSize += ebs.estLitSize + ZSTD_blockHeaderSize; + return ebs; } static int ZSTD_needSequenceEntropyTables(ZSTD_fseCTablesMetadata_t const* fseMetadata) @@ -21695,13 +18674,56 @@ static int ZSTD_needSequenceEntropyTables(ZSTD_fseCTablesMetadata_t const* fseMe return 0; } +static size_t countLiterals(seqStore_t const* seqStore, const seqDef* sp, size_t seqCount) +{ + size_t n, total = 0; + assert(sp != NULL); + for (n=0; n %zu bytes", seqCount, (const void*)sp, total); + return total; +} + +#define BYTESCALE 256 + +static size_t sizeBlockSequences(const seqDef* sp, size_t nbSeqs, + size_t targetBudget, size_t avgLitCost, size_t avgSeqCost, + int firstSubBlock) +{ + size_t n, budget = 0, inSize=0; + /* entropy headers */ + size_t const headerSize = (size_t)firstSubBlock * 120 * BYTESCALE; /* generous estimate */ + assert(firstSubBlock==0 || firstSubBlock==1); + budget += headerSize; + + /* first sequence => at least one sequence*/ + budget += sp[0].litLength * avgLitCost + avgSeqCost; + if (budget > targetBudget) return 1; + inSize = sp[0].litLength + (sp[0].mlBase+MINMATCH); + + /* loop over sequences */ + for (n=1; n targetBudget) + /* though continue to expand until the sub-block is deemed compressible */ + && (budget < inSize * BYTESCALE) ) + break; + } + + return n; +} + /** ZSTD_compressSubBlock_multi() : * Breaks super-block into multiple sub-blocks and compresses them. - * Entropy will be written to the first block. - * The following blocks will use repeat mode to compress. - * All sub-blocks are compressed blocks (no raw or rle blocks). - * @return : compressed size of the super block (which is multiple ZSTD blocks) - * Or 0 if it failed to compress. */ + * Entropy will be written into the first block. + * The following blocks use repeat_mode to compress. + * Sub-blocks are all compressed, except the last one when beneficial. + * @return : compressed size of the super block (which features multiple ZSTD blocks) + * or 0 if it failed to compress. */ static size_t ZSTD_compressSubBlock_multi(const seqStore_t* seqStorePtr, const ZSTD_compressedBlockState_t* prevCBlock, ZSTD_compressedBlockState_t* nextCBlock, @@ -21714,10 +18736,12 @@ static size_t ZSTD_compressSubBlock_multi(const seqStore_t* seqStorePtr, { const seqDef* const sstart = seqStorePtr->sequencesStart; const seqDef* const send = seqStorePtr->sequences; - const seqDef* sp = sstart; + const seqDef* sp = sstart; /* tracks progresses within seqStorePtr->sequences */ + size_t const nbSeqs = (size_t)(send - sstart); const BYTE* const lstart = seqStorePtr->litStart; const BYTE* const lend = seqStorePtr->lit; const BYTE* lp = lstart; + size_t const nbLiterals = (size_t)(lend - lstart); BYTE const* ip = (BYTE const*)src; BYTE const* const iend = ip + srcSize; BYTE* const ostart = (BYTE*)dst; @@ -21726,96 +18750,152 @@ static size_t ZSTD_compressSubBlock_multi(const seqStore_t* seqStorePtr, const BYTE* llCodePtr = seqStorePtr->llCode; const BYTE* mlCodePtr = seqStorePtr->mlCode; const BYTE* ofCodePtr = seqStorePtr->ofCode; - size_t targetCBlockSize = cctxParams->targetCBlockSize; - size_t litSize, seqCount; - int writeLitEntropy = entropyMetadata->hufMetadata.hType == set_compressed; + size_t const minTarget = ZSTD_TARGETCBLOCKSIZE_MIN; /* enforce minimum size, to reduce undesirable side effects */ + size_t const targetCBlockSize = MAX(minTarget, cctxParams->targetCBlockSize); + int writeLitEntropy = (entropyMetadata->hufMetadata.hType == set_compressed); int writeSeqEntropy = 1; - int lastSequence = 0; - DEBUGLOG(5, "ZSTD_compressSubBlock_multi (litSize=%u, nbSeq=%u)", - (unsigned)(lend-lp), (unsigned)(send-sstart)); - - litSize = 0; - seqCount = 0; - do { - size_t cBlockSizeEstimate = 0; - if (sstart == send) { - lastSequence = 1; - } else { - const seqDef* const sequence = sp + seqCount; - lastSequence = sequence == send - 1; - litSize += ZSTD_getSequenceLength(seqStorePtr, sequence).litLength; - seqCount++; - } - if (lastSequence) { - assert(lp <= lend); - assert(litSize <= (size_t)(lend - lp)); - litSize = (size_t)(lend - lp); - } - /* I think there is an optimization opportunity here. - * Calling ZSTD_estimateSubBlockSize for every sequence can be wasteful - * since it recalculates estimate from scratch. - * For example, it would recount literal distribution and symbol codes every time. - */ - cBlockSizeEstimate = ZSTD_estimateSubBlockSize(lp, litSize, ofCodePtr, llCodePtr, mlCodePtr, seqCount, - &nextCBlock->entropy, entropyMetadata, - workspace, wkspSize, writeLitEntropy, writeSeqEntropy); - if (cBlockSizeEstimate > targetCBlockSize || lastSequence) { - int litEntropyWritten = 0; - int seqEntropyWritten = 0; - const size_t decompressedSize = ZSTD_seqDecompressedSize(seqStorePtr, sp, seqCount, litSize, lastSequence); - const size_t cSize = ZSTD_compressSubBlock(&nextCBlock->entropy, entropyMetadata, - sp, seqCount, - lp, litSize, - llCodePtr, mlCodePtr, ofCodePtr, - cctxParams, - op, oend-op, - bmi2, writeLitEntropy, writeSeqEntropy, - &litEntropyWritten, &seqEntropyWritten, - lastBlock && lastSequence); - FORWARD_IF_ERROR(cSize, "ZSTD_compressSubBlock failed"); - if (cSize > 0 && cSize < decompressedSize) { - DEBUGLOG(5, "Committed the sub-block"); - assert(ip + decompressedSize <= iend); - ip += decompressedSize; - sp += seqCount; - lp += litSize; - op += cSize; - llCodePtr += seqCount; - mlCodePtr += seqCount; - ofCodePtr += seqCount; - litSize = 0; - seqCount = 0; - /* Entropy only needs to be written once */ - if (litEntropyWritten) { - writeLitEntropy = 0; - } - if (seqEntropyWritten) { - writeSeqEntropy = 0; - } + DEBUGLOG(5, "ZSTD_compressSubBlock_multi (srcSize=%u, litSize=%u, nbSeq=%u)", + (unsigned)srcSize, (unsigned)(lend-lstart), (unsigned)(send-sstart)); + + /* let's start by a general estimation for the full block */ + if (nbSeqs > 0) { + EstimatedBlockSize const ebs = + ZSTD_estimateSubBlockSize(lp, nbLiterals, + ofCodePtr, llCodePtr, mlCodePtr, nbSeqs, + &nextCBlock->entropy, entropyMetadata, + workspace, wkspSize, + writeLitEntropy, writeSeqEntropy); + /* quick estimation */ + size_t const avgLitCost = nbLiterals ? (ebs.estLitSize * BYTESCALE) / nbLiterals : BYTESCALE; + size_t const avgSeqCost = ((ebs.estBlockSize - ebs.estLitSize) * BYTESCALE) / nbSeqs; + const size_t nbSubBlocks = MAX((ebs.estBlockSize + (targetCBlockSize/2)) / targetCBlockSize, 1); + size_t n, avgBlockBudget, blockBudgetSupp=0; + avgBlockBudget = (ebs.estBlockSize * BYTESCALE) / nbSubBlocks; + DEBUGLOG(5, "estimated fullblock size=%u bytes ; avgLitCost=%.2f ; avgSeqCost=%.2f ; targetCBlockSize=%u, nbSubBlocks=%u ; avgBlockBudget=%.0f bytes", + (unsigned)ebs.estBlockSize, (double)avgLitCost/BYTESCALE, (double)avgSeqCost/BYTESCALE, + (unsigned)targetCBlockSize, (unsigned)nbSubBlocks, (double)avgBlockBudget/BYTESCALE); + /* simplification: if estimates states that the full superblock doesn't compress, just bail out immediately + * this will result in the production of a single uncompressed block covering @srcSize.*/ + if (ebs.estBlockSize > srcSize) return 0; + + /* compress and write sub-blocks */ + assert(nbSubBlocks>0); + for (n=0; n < nbSubBlocks-1; n++) { + /* determine nb of sequences for current sub-block + nbLiterals from next sequence */ + size_t const seqCount = sizeBlockSequences(sp, (size_t)(send-sp), + avgBlockBudget + blockBudgetSupp, avgLitCost, avgSeqCost, n==0); + /* if reached last sequence : break to last sub-block (simplification) */ + assert(seqCount <= (size_t)(send-sp)); + if (sp + seqCount == send) break; + assert(seqCount > 0); + /* compress sub-block */ + { int litEntropyWritten = 0; + int seqEntropyWritten = 0; + size_t litSize = countLiterals(seqStorePtr, sp, seqCount); + const size_t decompressedSize = + ZSTD_seqDecompressedSize(seqStorePtr, sp, seqCount, litSize, 0); + size_t const cSize = ZSTD_compressSubBlock(&nextCBlock->entropy, entropyMetadata, + sp, seqCount, + lp, litSize, + llCodePtr, mlCodePtr, ofCodePtr, + cctxParams, + op, (size_t)(oend-op), + bmi2, writeLitEntropy, writeSeqEntropy, + &litEntropyWritten, &seqEntropyWritten, + 0); + FORWARD_IF_ERROR(cSize, "ZSTD_compressSubBlock failed"); + + /* check compressibility, update state components */ + if (cSize > 0 && cSize < decompressedSize) { + DEBUGLOG(5, "Committed sub-block compressing %u bytes => %u bytes", + (unsigned)decompressedSize, (unsigned)cSize); + assert(ip + decompressedSize <= iend); + ip += decompressedSize; + lp += litSize; + op += cSize; + llCodePtr += seqCount; + mlCodePtr += seqCount; + ofCodePtr += seqCount; + /* Entropy only needs to be written once */ + if (litEntropyWritten) { + writeLitEntropy = 0; + } + if (seqEntropyWritten) { + writeSeqEntropy = 0; + } + sp += seqCount; + blockBudgetSupp = 0; + } } + /* otherwise : do not compress yet, coalesce current sub-block with following one */ + } + } /* if (nbSeqs > 0) */ + + /* write last block */ + DEBUGLOG(5, "Generate last sub-block: %u sequences remaining", (unsigned)(send - sp)); + { int litEntropyWritten = 0; + int seqEntropyWritten = 0; + size_t litSize = (size_t)(lend - lp); + size_t seqCount = (size_t)(send - sp); + const size_t decompressedSize = + ZSTD_seqDecompressedSize(seqStorePtr, sp, seqCount, litSize, 1); + size_t const cSize = ZSTD_compressSubBlock(&nextCBlock->entropy, entropyMetadata, + sp, seqCount, + lp, litSize, + llCodePtr, mlCodePtr, ofCodePtr, + cctxParams, + op, (size_t)(oend-op), + bmi2, writeLitEntropy, writeSeqEntropy, + &litEntropyWritten, &seqEntropyWritten, + lastBlock); + FORWARD_IF_ERROR(cSize, "ZSTD_compressSubBlock failed"); + + /* update pointers, the nb of literals borrowed from next sequence must be preserved */ + if (cSize > 0 && cSize < decompressedSize) { + DEBUGLOG(5, "Last sub-block compressed %u bytes => %u bytes", + (unsigned)decompressedSize, (unsigned)cSize); + assert(ip + decompressedSize <= iend); + ip += decompressedSize; + lp += litSize; + op += cSize; + llCodePtr += seqCount; + mlCodePtr += seqCount; + ofCodePtr += seqCount; + /* Entropy only needs to be written once */ + if (litEntropyWritten) { + writeLitEntropy = 0; + } + if (seqEntropyWritten) { + writeSeqEntropy = 0; } + sp += seqCount; } - } while (!lastSequence); + } + + if (writeLitEntropy) { - DEBUGLOG(5, "ZSTD_compressSubBlock_multi has literal entropy tables unwritten"); + DEBUGLOG(5, "Literal entropy tables were never written"); ZSTD_memcpy(&nextCBlock->entropy.huf, &prevCBlock->entropy.huf, sizeof(prevCBlock->entropy.huf)); } if (writeSeqEntropy && ZSTD_needSequenceEntropyTables(&entropyMetadata->fseMetadata)) { /* If we haven't written our entropy tables, then we've violated our contract and * must emit an uncompressed block. */ - DEBUGLOG(5, "ZSTD_compressSubBlock_multi has sequence entropy tables unwritten"); + DEBUGLOG(5, "Sequence entropy tables were never written => cancel, emit an uncompressed block"); return 0; } + if (ip < iend) { - size_t const cSize = ZSTD_noCompressBlock(op, oend - op, ip, iend - ip, lastBlock); - DEBUGLOG(5, "ZSTD_compressSubBlock_multi last sub-block uncompressed, %zu bytes", (size_t)(iend - ip)); + /* some data left : last part of the block sent uncompressed */ + size_t const rSize = (size_t)((iend - ip)); + size_t const cSize = ZSTD_noCompressBlock(op, (size_t)(oend - op), ip, rSize, lastBlock); + DEBUGLOG(5, "Generate last uncompressed sub-block of %u bytes", (unsigned)(rSize)); FORWARD_IF_ERROR(cSize, "ZSTD_noCompressBlock failed"); assert(cSize != 0); op += cSize; /* We have to regenerate the repcodes because we've skipped some sequences */ if (sp < send) { - seqDef const* seq; + const seqDef* seq; repcodes_t rep; ZSTD_memcpy(&rep, prevCBlock->rep, sizeof(rep)); for (seq = sstart; seq < sp; ++seq) { @@ -21824,14 +18904,17 @@ static size_t ZSTD_compressSubBlock_multi(const seqStore_t* seqStorePtr, ZSTD_memcpy(nextCBlock->rep, &rep, sizeof(rep)); } } - DEBUGLOG(5, "ZSTD_compressSubBlock_multi compressed"); - return op-ostart; + + DEBUGLOG(5, "ZSTD_compressSubBlock_multi compressed all subBlocks: total compressed size = %u", + (unsigned)(op-ostart)); + return (size_t)(op-ostart); } size_t ZSTD_compressSuperBlock(ZSTD_CCtx* zc, void* dst, size_t dstCapacity, - void const* src, size_t srcSize, - unsigned lastBlock) { + const void* src, size_t srcSize, + unsigned lastBlock) +{ ZSTD_entropyCTablesMetadata_t entropyMetadata; FORWARD_IF_ERROR(ZSTD_buildBlockEntropyStats(&zc->seqStore, @@ -23217,7 +20300,7 @@ size_t ZSTD_CCtxParams_setParameter(ZSTD_CCtx_params* CCtxParams, #else FORWARD_IF_ERROR(ZSTD_cParam_clampBounds(param, &value), ""); CCtxParams->nbWorkers = value; - return CCtxParams->nbWorkers; + return (size_t)(CCtxParams->nbWorkers); #endif case ZSTD_c_jobSize : @@ -23241,7 +20324,7 @@ size_t ZSTD_CCtxParams_setParameter(ZSTD_CCtx_params* CCtxParams, #else FORWARD_IF_ERROR(ZSTD_cParam_clampBounds(ZSTD_c_overlapLog, &value), ""); CCtxParams->overlapLog = value; - return CCtxParams->overlapLog; + return (size_t)CCtxParams->overlapLog; #endif case ZSTD_c_rsyncable : @@ -23251,7 +20334,7 @@ size_t ZSTD_CCtxParams_setParameter(ZSTD_CCtx_params* CCtxParams, #else FORWARD_IF_ERROR(ZSTD_cParam_clampBounds(ZSTD_c_overlapLog, &value), ""); CCtxParams->rsyncable = value; - return CCtxParams->rsyncable; + return (size_t)CCtxParams->rsyncable; #endif case ZSTD_c_enableDedicatedDictSearch : @@ -23288,8 +20371,10 @@ size_t ZSTD_CCtxParams_setParameter(ZSTD_CCtx_params* CCtxParams, return CCtxParams->ldmParams.hashRateLog; case ZSTD_c_targetCBlockSize : - if (value!=0) /* 0 ==> default */ + if (value!=0) { /* 0 ==> default */ + value = MAX(value, ZSTD_TARGETCBLOCKSIZE_MIN); BOUNDCHECK(ZSTD_c_targetCBlockSize, value); + } CCtxParams->targetCBlockSize = (U32)value; return CCtxParams->targetCBlockSize; @@ -23317,7 +20402,7 @@ size_t ZSTD_CCtxParams_setParameter(ZSTD_CCtx_params* CCtxParams, case ZSTD_c_validateSequences: BOUNDCHECK(ZSTD_c_validateSequences, value); CCtxParams->validateSequences = value; - return CCtxParams->validateSequences; + return (size_t)CCtxParams->validateSequences; case ZSTD_c_useBlockSplitter: BOUNDCHECK(ZSTD_c_useBlockSplitter, value); @@ -23332,7 +20417,7 @@ size_t ZSTD_CCtxParams_setParameter(ZSTD_CCtx_params* CCtxParams, case ZSTD_c_deterministicRefPrefix: BOUNDCHECK(ZSTD_c_deterministicRefPrefix, value); CCtxParams->deterministicRefPrefix = !!value; - return CCtxParams->deterministicRefPrefix; + return (size_t)CCtxParams->deterministicRefPrefix; case ZSTD_c_prefetchCDictTables: BOUNDCHECK(ZSTD_c_prefetchCDictTables, value); @@ -23342,7 +20427,7 @@ size_t ZSTD_CCtxParams_setParameter(ZSTD_CCtx_params* CCtxParams, case ZSTD_c_enableSeqProducerFallback: BOUNDCHECK(ZSTD_c_enableSeqProducerFallback, value); CCtxParams->enableMatchFinderFallback = value; - return CCtxParams->enableMatchFinderFallback; + return (size_t)CCtxParams->enableMatchFinderFallback; case ZSTD_c_maxBlockSize: if (value!=0) /* 0 ==> default */ @@ -24008,8 +21093,8 @@ ZSTD_sizeof_matchState(const ZSTD_compressionParameters* const cParams, + ZSTD_cwksp_aligned_alloc_size((MaxLL+1) * sizeof(U32)) + ZSTD_cwksp_aligned_alloc_size((MaxOff+1) * sizeof(U32)) + ZSTD_cwksp_aligned_alloc_size((1<strategy, useRowMatchFinder) ? ZSTD_cwksp_aligned_alloc_size(hSize) : 0; @@ -24392,8 +21477,8 @@ ZSTD_reset_matchState(ZSTD_matchState_t* ms, ms->opt.litLengthFreq = (unsigned*)ZSTD_cwksp_reserve_aligned(ws, (MaxLL+1) * sizeof(unsigned)); ms->opt.matchLengthFreq = (unsigned*)ZSTD_cwksp_reserve_aligned(ws, (MaxML+1) * sizeof(unsigned)); ms->opt.offCodeFreq = (unsigned*)ZSTD_cwksp_reserve_aligned(ws, (MaxOff+1) * sizeof(unsigned)); - ms->opt.matchTable = (ZSTD_match_t*)ZSTD_cwksp_reserve_aligned(ws, (ZSTD_OPT_NUM+1) * sizeof(ZSTD_match_t)); - ms->opt.priceTable = (ZSTD_optimal_t*)ZSTD_cwksp_reserve_aligned(ws, (ZSTD_OPT_NUM+1) * sizeof(ZSTD_optimal_t)); + ms->opt.matchTable = (ZSTD_match_t*)ZSTD_cwksp_reserve_aligned(ws, ZSTD_OPT_SIZE * sizeof(ZSTD_match_t)); + ms->opt.priceTable = (ZSTD_optimal_t*)ZSTD_cwksp_reserve_aligned(ws, ZSTD_OPT_SIZE * sizeof(ZSTD_optimal_t)); } ms->cParams = *cParams; @@ -24483,7 +21568,6 @@ static size_t ZSTD_resetCCtx_internal(ZSTD_CCtx* zc, ZSTD_estimateCCtxSize_usingCCtxParams_internal( ¶ms->cParams, ¶ms->ldmParams, zc->staticSize != 0, params->useRowMatchFinder, buffInSize, buffOutSize, pledgedSrcSize, ZSTD_hasExtSeqProd(params), params->maxBlockSize); - int resizeWorkspace; FORWARD_IF_ERROR(neededSpace, "cctx size estimate failed!"); @@ -24492,7 +21576,7 @@ static size_t ZSTD_resetCCtx_internal(ZSTD_CCtx* zc, { /* Check if workspace is large enough, alloc a new one if needed */ int const workspaceTooSmall = ZSTD_cwksp_sizeof(ws) < neededSpace; int const workspaceWasteful = ZSTD_cwksp_check_wasteful(ws, neededSpace); - resizeWorkspace = workspaceTooSmall || workspaceWasteful; + int resizeWorkspace = workspaceTooSmall || workspaceWasteful; DEBUGLOG(4, "Need %zu B workspace", neededSpace); DEBUGLOG(4, "windowSize: %zu - blockSize: %zu", windowSize, blockSize); @@ -25709,29 +22793,38 @@ static size_t ZSTD_buildSeqStore(ZSTD_CCtx* zc, const void* src, size_t srcSize) return ZSTDbss_compress; } -static void ZSTD_copyBlockSequences(ZSTD_CCtx* zc) +static size_t ZSTD_copyBlockSequences(SeqCollector* seqCollector, const seqStore_t* seqStore, const U32 prevRepcodes[ZSTD_REP_NUM]) { - const seqStore_t* seqStore = ZSTD_getSeqStore(zc); - const seqDef* seqStoreSeqs = seqStore->sequencesStart; - size_t seqStoreSeqSize = seqStore->sequences - seqStoreSeqs; - size_t seqStoreLiteralsSize = (size_t)(seqStore->lit - seqStore->litStart); - size_t literalsRead = 0; - size_t lastLLSize; + const seqDef* inSeqs = seqStore->sequencesStart; + const size_t nbInSequences = seqStore->sequences - inSeqs; + const size_t nbInLiterals = (size_t)(seqStore->lit - seqStore->litStart); - ZSTD_Sequence* outSeqs = &zc->seqCollector.seqStart[zc->seqCollector.seqIndex]; + ZSTD_Sequence* outSeqs = seqCollector->seqIndex == 0 ? seqCollector->seqStart : seqCollector->seqStart + seqCollector->seqIndex; + const size_t nbOutSequences = nbInSequences + 1; + size_t nbOutLiterals = 0; + repcodes_t repcodes; size_t i; - repcodes_t updatedRepcodes; - assert(zc->seqCollector.seqIndex + 1 < zc->seqCollector.maxSequences); - /* Ensure we have enough space for last literals "sequence" */ - assert(zc->seqCollector.maxSequences >= seqStoreSeqSize + 1); - ZSTD_memcpy(updatedRepcodes.rep, zc->blockState.prevCBlock->rep, sizeof(repcodes_t)); - for (i = 0; i < seqStoreSeqSize; ++i) { - U32 rawOffset = seqStoreSeqs[i].offBase - ZSTD_REP_NUM; - outSeqs[i].litLength = seqStoreSeqs[i].litLength; - outSeqs[i].matchLength = seqStoreSeqs[i].mlBase + MINMATCH; + /* Bounds check that we have enough space for every input sequence + * and the block delimiter + */ + assert(seqCollector->seqIndex <= seqCollector->maxSequences); + RETURN_ERROR_IF( + nbOutSequences > (size_t)(seqCollector->maxSequences - seqCollector->seqIndex), + dstSize_tooSmall, + "Not enough space to copy sequences"); + + ZSTD_memcpy(&repcodes, prevRepcodes, sizeof(repcodes)); + for (i = 0; i < nbInSequences; ++i) { + U32 rawOffset; + outSeqs[i].litLength = inSeqs[i].litLength; + outSeqs[i].matchLength = inSeqs[i].mlBase + MINMATCH; outSeqs[i].rep = 0; + /* Handle the possible single length >= 64K + * There can only be one because we add MINMATCH to every match length, + * and blocks are at most 128K. + */ if (i == seqStore->longLengthPos) { if (seqStore->longLengthType == ZSTD_llt_literalLength) { outSeqs[i].litLength += 0x10000; @@ -25740,41 +22833,55 @@ static void ZSTD_copyBlockSequences(ZSTD_CCtx* zc) } } - if (seqStoreSeqs[i].offBase <= ZSTD_REP_NUM) { - /* Derive the correct offset corresponding to a repcode */ - outSeqs[i].rep = seqStoreSeqs[i].offBase; + /* Determine the raw offset given the offBase, which may be a repcode. */ + if (OFFBASE_IS_REPCODE(inSeqs[i].offBase)) { + const U32 repcode = OFFBASE_TO_REPCODE(inSeqs[i].offBase); + assert(repcode > 0); + outSeqs[i].rep = repcode; if (outSeqs[i].litLength != 0) { - rawOffset = updatedRepcodes.rep[outSeqs[i].rep - 1]; + rawOffset = repcodes.rep[repcode - 1]; } else { - if (outSeqs[i].rep == 3) { - rawOffset = updatedRepcodes.rep[0] - 1; + if (repcode == 3) { + assert(repcodes.rep[0] > 1); + rawOffset = repcodes.rep[0] - 1; } else { - rawOffset = updatedRepcodes.rep[outSeqs[i].rep]; + rawOffset = repcodes.rep[repcode]; } } + } else { + rawOffset = OFFBASE_TO_OFFSET(inSeqs[i].offBase); } outSeqs[i].offset = rawOffset; - /* seqStoreSeqs[i].offset == offCode+1, and ZSTD_updateRep() expects offCode - so we provide seqStoreSeqs[i].offset - 1 */ - ZSTD_updateRep(updatedRepcodes.rep, - seqStoreSeqs[i].offBase, - seqStoreSeqs[i].litLength == 0); - literalsRead += outSeqs[i].litLength; + + /* Update repcode history for the sequence */ + ZSTD_updateRep(repcodes.rep, + inSeqs[i].offBase, + inSeqs[i].litLength == 0); + + nbOutLiterals += outSeqs[i].litLength; } /* Insert last literals (if any exist) in the block as a sequence with ml == off == 0. * If there are no last literals, then we'll emit (of: 0, ml: 0, ll: 0), which is a marker * for the block boundary, according to the API. */ - assert(seqStoreLiteralsSize >= literalsRead); - lastLLSize = seqStoreLiteralsSize - literalsRead; - outSeqs[i].litLength = (U32)lastLLSize; - outSeqs[i].matchLength = outSeqs[i].offset = outSeqs[i].rep = 0; - seqStoreSeqSize++; - zc->seqCollector.seqIndex += seqStoreSeqSize; + assert(nbInLiterals >= nbOutLiterals); + { + const size_t lastLLSize = nbInLiterals - nbOutLiterals; + outSeqs[nbInSequences].litLength = (U32)lastLLSize; + outSeqs[nbInSequences].matchLength = 0; + outSeqs[nbInSequences].offset = 0; + assert(nbOutSequences == nbInSequences + 1); + } + seqCollector->seqIndex += nbOutSequences; + assert(seqCollector->seqIndex <= seqCollector->maxSequences); + + return 0; } size_t ZSTD_sequenceBound(size_t srcSize) { - return (srcSize / ZSTD_MINMATCH_MIN) + 1; + const size_t maxNbSeq = (srcSize / ZSTD_MINMATCH_MIN) + 1; + const size_t maxNbDelims = (srcSize / ZSTD_BLOCKSIZE_MAX_MIN) + 1; + return maxNbSeq + maxNbDelims; } size_t ZSTD_generateSequences(ZSTD_CCtx* zc, ZSTD_Sequence* outSeqs, @@ -25783,6 +22890,16 @@ size_t ZSTD_generateSequences(ZSTD_CCtx* zc, ZSTD_Sequence* outSeqs, const size_t dstCapacity = ZSTD_compressBound(srcSize); void* dst = ZSTD_customMalloc(dstCapacity, ZSTD_defaultCMem); SeqCollector seqCollector; + { + int targetCBlockSize; + FORWARD_IF_ERROR(ZSTD_CCtx_getParameter(zc, ZSTD_c_targetCBlockSize, &targetCBlockSize), ""); + RETURN_ERROR_IF(targetCBlockSize != 0, parameter_unsupported, "targetCBlockSize != 0"); + } + { + int nbWorkers; + FORWARD_IF_ERROR(ZSTD_CCtx_getParameter(zc, ZSTD_c_nbWorkers, &nbWorkers), ""); + RETURN_ERROR_IF(nbWorkers != 0, parameter_unsupported, "nbWorkers != 0"); + } RETURN_ERROR_IF(dst == NULL, memory_allocation, "NULL pointer!"); @@ -25792,8 +22909,12 @@ size_t ZSTD_generateSequences(ZSTD_CCtx* zc, ZSTD_Sequence* outSeqs, seqCollector.maxSequences = outSeqsSize; zc->seqCollector = seqCollector; - ZSTD_compress2(zc, dst, dstCapacity, src, srcSize); - ZSTD_customFree(dst, ZSTD_defaultCMem); + { + const size_t ret = ZSTD_compress2(zc, dst, dstCapacity, src, srcSize); + ZSTD_customFree(dst, ZSTD_defaultCMem); + FORWARD_IF_ERROR(ret, "ZSTD_compress2 failed"); + } + assert(zc->seqCollector.seqIndex <= ZSTD_sequenceBound(srcSize)); return zc->seqCollector.seqIndex; } @@ -26386,8 +23507,9 @@ ZSTD_compressSeqStore_singleBlock(ZSTD_CCtx* zc, cSeqsSize = 1; } + /* Sequence collection not supported when block splitting */ if (zc->seqCollector.collectSequences) { - ZSTD_copyBlockSequences(zc); + FORWARD_IF_ERROR(ZSTD_copyBlockSequences(&zc->seqCollector, seqStore, dRepOriginal.rep), "copyBlockSequences failed"); ZSTD_blockState_confirmRepcodesAndEntropyTables(&zc->blockState); return 0; } @@ -26609,6 +23731,7 @@ ZSTD_compressBlock_splitBlock(ZSTD_CCtx* zc, if (bss == ZSTDbss_noCompress) { if (zc->blockState.prevCBlock->entropy.fse.offcode_repeatMode == FSE_repeat_valid) zc->blockState.prevCBlock->entropy.fse.offcode_repeatMode = FSE_repeat_check; + RETURN_ERROR_IF(zc->seqCollector.collectSequences, sequenceProducer_failed, "Uncompressible block"); cSize = ZSTD_noCompressBlock(dst, dstCapacity, src, srcSize, lastBlock); FORWARD_IF_ERROR(cSize, "ZSTD_noCompressBlock failed"); DEBUGLOG(4, "ZSTD_compressBlock_splitBlock: Nocompress block"); @@ -26641,11 +23764,15 @@ ZSTD_compressBlock_internal(ZSTD_CCtx* zc, { const size_t bss = ZSTD_buildSeqStore(zc, src, srcSize); FORWARD_IF_ERROR(bss, "ZSTD_buildSeqStore failed"); - if (bss == ZSTDbss_noCompress) { cSize = 0; goto out; } + if (bss == ZSTDbss_noCompress) { + RETURN_ERROR_IF(zc->seqCollector.collectSequences, sequenceProducer_failed, "Uncompressible block"); + cSize = 0; + goto out; + } } if (zc->seqCollector.collectSequences) { - ZSTD_copyBlockSequences(zc); + FORWARD_IF_ERROR(ZSTD_copyBlockSequences(&zc->seqCollector, ZSTD_getSeqStore(zc), zc->blockState.prevCBlock->rep), "copyBlockSequences failed"); ZSTD_blockState_confirmRepcodesAndEntropyTables(&zc->blockState); return 0; } @@ -27523,14 +24650,13 @@ static size_t ZSTD_writeEpilogue(ZSTD_CCtx* cctx, void* dst, size_t dstCapacity) { BYTE* const ostart = (BYTE*)dst; BYTE* op = ostart; - size_t fhSize = 0; DEBUGLOG(4, "ZSTD_writeEpilogue"); RETURN_ERROR_IF(cctx->stage == ZSTDcs_created, stage_wrong, "init missing"); /* special case : empty frame */ if (cctx->stage == ZSTDcs_init) { - fhSize = ZSTD_writeFrameHeader(dst, dstCapacity, &cctx->appliedParams, 0, 0); + size_t fhSize = ZSTD_writeFrameHeader(dst, dstCapacity, &cctx->appliedParams, 0, 0); FORWARD_IF_ERROR(fhSize, "ZSTD_writeFrameHeader failed"); dstCapacity -= fhSize; op += fhSize; @@ -32459,18 +29585,18 @@ ZSTD_row_getMatchMask(const BYTE* const tagRow, const BYTE tag, const U32 headGr /* The high-level approach of the SIMD row based match finder is as follows: * - Figure out where to insert the new entry: - * - Generate a hash from a byte along with an additional 1-byte "short hash". The additional byte is our "tag" - * - The hashTable is effectively split into groups or "rows" of 16 or 32 entries of U32, and the hash determines + * - Generate a hash for current input posistion and split it into a one byte of tag and `rowHashLog` bits of index. + * - The hash is salted by a value that changes on every contex reset, so when the same table is used + * we will avoid collisions that would otherwise slow us down by intorducing phantom matches. + * - The hashTable is effectively split into groups or "rows" of 15 or 31 entries of U32, and the index determines * which row to insert into. - * - Determine the correct position within the row to insert the entry into. Each row of 16 or 32 can - * be considered as a circular buffer with a "head" index that resides in the tagTable. - * - Also insert the "tag" into the equivalent row and position in the tagTable. - * - Note: The tagTable has 17 or 33 1-byte entries per row, due to 16 or 32 tags, and 1 "head" entry. - * The 17 or 33 entry rows are spaced out to occur every 32 or 64 bytes, respectively, - * for alignment/performance reasons, leaving some bytes unused. - * - Use SIMD to efficiently compare the tags in the tagTable to the 1-byte "short hash" and + * - Determine the correct position within the row to insert the entry into. Each row of 15 or 31 can + * be considered as a circular buffer with a "head" index that resides in the tagTable (overall 16 or 32 bytes + * per row). + * - Use SIMD to efficiently compare the tags in the tagTable to the 1-byte tag calculated for the position and * generate a bitfield that we can cycle through to check the collisions in the hash table. * - Pick the longest match. + * - Insert the tag into the equivalent row and position in the tagTable. */ FORCE_INLINE_TEMPLATE ZSTD_ALLOW_POINTER_OVERFLOW_ATTR @@ -34339,7 +31465,6 @@ size_t ZSTD_ldm_blockCompress(rawSeqStore_t* rawSeqStore, /* maybeSplitSequence updates rawSeqStore->pos */ rawSeq const sequence = maybeSplitSequence(rawSeqStore, (U32)(iend - ip), minMatch); - int i; /* End signal */ if (sequence.offset == 0) break; @@ -34352,6 +31477,7 @@ size_t ZSTD_ldm_blockCompress(rawSeqStore_t* rawSeqStore, /* Run the block compressor */ DEBUGLOG(5, "pos %u : calling block compressor on segment of size %u", (unsigned)(ip-istart), sequence.litLength); { + int i; size_t const newLitLength = blockCompressor(ms, seqStore, rep, ip, sequence.litLength); ip += sequence.litLength; @@ -34643,6 +31769,7 @@ static U32 ZSTD_rawLiteralsCost(const BYTE* const literals, U32 const litLength, const optState_t* const optPtr, int optLevel) { + DEBUGLOG(8, "ZSTD_rawLiteralsCost (%u literals)", litLength); if (litLength == 0) return 0; if (!ZSTD_compressedLiterals(optPtr)) @@ -34942,7 +32069,7 @@ void ZSTD_updateTree_internal( const BYTE* const base = ms->window.base; U32 const target = (U32)(ip - base); U32 idx = ms->nextToUpdate; - DEBUGLOG(6, "ZSTD_updateTree_internal, from %u to %u (dictMode:%u)", + DEBUGLOG(7, "ZSTD_updateTree_internal, from %u to %u (dictMode:%u)", idx, target, dictMode); while(idx < target) { @@ -35423,11 +32550,6 @@ ZSTD_optLdm_processMatchCandidate(ZSTD_optLdm_t* optLdm, * Optimal parser *********************************/ -static U32 ZSTD_totalLen(ZSTD_optimal_t sol) -{ - return sol.litlen + sol.mlen; -} - #if 0 /* debug */ static void @@ -35445,6 +32567,10 @@ listStats(const U32* table, int lastEltID) #endif +#define LIT_PRICE(_p) (int)ZSTD_rawLiteralsCost(_p, 1, optStatePtr, optLevel) +#define LL_PRICE(_l) (int)ZSTD_litLengthPrice(_l, optStatePtr, optLevel) +#define LL_INCPRICE(_l) (LL_PRICE(_l) - LL_PRICE(_l-1)) + FORCE_INLINE_TEMPLATE ZSTD_ALLOW_POINTER_OVERFLOW_ATTR size_t @@ -35473,10 +32599,10 @@ ZSTD_compressBlock_opt_generic(ZSTD_matchState_t* ms, ZSTD_optimal_t* const opt = optStatePtr->priceTable; ZSTD_match_t* const matches = optStatePtr->matchTable; - ZSTD_optimal_t lastSequence; + ZSTD_optimal_t lastStretch; ZSTD_optLdm_t optLdm; - ZSTD_memset(&lastSequence, 0, sizeof(ZSTD_optimal_t)); + ZSTD_memset(&lastStretch, 0, sizeof(ZSTD_optimal_t)); optLdm.seqStore = ms->ldmSeqStore ? *ms->ldmSeqStore : kNullRawSeqStore; optLdm.endPosInBlock = optLdm.startPosInBlock = optLdm.offset = 0; @@ -35498,19 +32624,31 @@ ZSTD_compressBlock_opt_generic(ZSTD_matchState_t* ms, U32 const ll0 = !litlen; U32 nbMatches = getAllMatches(matches, ms, &nextToUpdate3, ip, iend, rep, ll0, minMatch); ZSTD_optLdm_processMatchCandidate(&optLdm, matches, &nbMatches, - (U32)(ip-istart), (U32)(iend - ip)); - if (!nbMatches) { ip++; continue; } + (U32)(ip-istart), (U32)(iend-ip)); + if (!nbMatches) { + DEBUGLOG(8, "no match found at cPos %u", (unsigned)(ip-istart)); + ip++; + continue; + } + + /* Match found: let's store this solution, and eventually find more candidates. + * During this forward pass, @opt is used to store stretches, + * defined as "a match followed by N literals". + * Note how this is different from a Sequence, which is "N literals followed by a match". + * Storing stretches allows us to store different match predecessors + * for each literal position part of a literals run. */ /* initialize opt[0] */ - { U32 i ; for (i=0; i immediate encoding */ { U32 const maxML = matches[nbMatches-1].len; @@ -35519,82 +32657,106 @@ ZSTD_compressBlock_opt_generic(ZSTD_matchState_t* ms, nbMatches, maxML, maxOffBase, (U32)(ip-prefixStart)); if (maxML > sufficient_len) { - lastSequence.litlen = litlen; - lastSequence.mlen = maxML; - lastSequence.off = maxOffBase; - DEBUGLOG(6, "large match (%u>%u), immediate encoding", + lastStretch.litlen = 0; + lastStretch.mlen = maxML; + lastStretch.off = maxOffBase; + DEBUGLOG(6, "large match (%u>%u) => immediate encoding", maxML, sufficient_len); cur = 0; - last_pos = ZSTD_totalLen(lastSequence); + last_pos = maxML; goto _shortestPath; } } /* set prices for first matches starting position == 0 */ assert(opt[0].price >= 0); - { U32 const literalsPrice = (U32)opt[0].price + ZSTD_litLengthPrice(0, optStatePtr, optLevel); - U32 pos; + { U32 pos; U32 matchNb; for (pos = 1; pos < minMatch; pos++) { - opt[pos].price = ZSTD_MAX_PRICE; /* mlen, litlen and price will be fixed during forward scanning */ + opt[pos].price = ZSTD_MAX_PRICE; + opt[pos].mlen = 0; + opt[pos].litlen = litlen + pos; } for (matchNb = 0; matchNb < nbMatches; matchNb++) { U32 const offBase = matches[matchNb].off; U32 const end = matches[matchNb].len; for ( ; pos <= end ; pos++ ) { - U32 const matchPrice = ZSTD_getMatchPrice(offBase, pos, optStatePtr, optLevel); - U32 const sequencePrice = literalsPrice + matchPrice; + int const matchPrice = (int)ZSTD_getMatchPrice(offBase, pos, optStatePtr, optLevel); + int const sequencePrice = opt[0].price + matchPrice; DEBUGLOG(7, "rPos:%u => set initial price : %.2f", - pos, ZSTD_fCost((int)sequencePrice)); + pos, ZSTD_fCost(sequencePrice)); opt[pos].mlen = pos; opt[pos].off = offBase; - opt[pos].litlen = litlen; - opt[pos].price = (int)sequencePrice; - } } + opt[pos].litlen = 0; /* end of match */ + opt[pos].price = sequencePrice + LL_PRICE(0); + } + } last_pos = pos-1; + opt[pos].price = ZSTD_MAX_PRICE; } } /* check further positions */ for (cur = 1; cur <= last_pos; cur++) { const BYTE* const inr = ip + cur; - assert(cur < ZSTD_OPT_NUM); + assert(cur <= ZSTD_OPT_NUM); DEBUGLOG(7, "cPos:%zi==rPos:%u", inr-istart, cur); /* Fix current position with one literal if cheaper */ - { U32 const litlen = (opt[cur-1].mlen == 0) ? opt[cur-1].litlen + 1 : 1; + { U32 const litlen = opt[cur-1].litlen + 1; int const price = opt[cur-1].price - + (int)ZSTD_rawLiteralsCost(ip+cur-1, 1, optStatePtr, optLevel) - + (int)ZSTD_litLengthPrice(litlen, optStatePtr, optLevel) - - (int)ZSTD_litLengthPrice(litlen-1, optStatePtr, optLevel); + + LIT_PRICE(ip+cur-1) + + LL_INCPRICE(litlen); assert(price < 1000000000); /* overflow check */ if (price <= opt[cur].price) { + ZSTD_optimal_t const prevMatch = opt[cur]; DEBUGLOG(7, "cPos:%zi==rPos:%u : better price (%.2f<=%.2f) using literal (ll==%u) (hist:%u,%u,%u)", inr-istart, cur, ZSTD_fCost(price), ZSTD_fCost(opt[cur].price), litlen, opt[cur-1].rep[0], opt[cur-1].rep[1], opt[cur-1].rep[2]); - opt[cur].mlen = 0; - opt[cur].off = 0; + opt[cur] = opt[cur-1]; opt[cur].litlen = litlen; opt[cur].price = price; + if ( (optLevel >= 1) /* additional check only for higher modes */ + && (prevMatch.litlen == 0) /* replace a match */ + && (LL_INCPRICE(1) < 0) /* ll1 is cheaper than ll0 */ + && LIKELY(ip + cur < iend) + ) { + /* check next position, in case it would be cheaper */ + int with1literal = prevMatch.price + LIT_PRICE(ip+cur) + LL_INCPRICE(1); + int withMoreLiterals = price + LIT_PRICE(ip+cur) + LL_INCPRICE(litlen+1); + DEBUGLOG(7, "then at next rPos %u : match+1lit %.2f vs %ulits %.2f", + cur+1, ZSTD_fCost(with1literal), litlen+1, ZSTD_fCost(withMoreLiterals)); + if ( (with1literal < withMoreLiterals) + && (with1literal < opt[cur+1].price) ) { + /* update offset history - before it disappears */ + U32 const prev = cur - prevMatch.mlen; + repcodes_t const newReps = ZSTD_newRep(opt[prev].rep, prevMatch.off, opt[prev].litlen==0); + assert(cur >= prevMatch.mlen); + DEBUGLOG(7, "==> match+1lit is cheaper (%.2f < %.2f) (hist:%u,%u,%u) !", + ZSTD_fCost(with1literal), ZSTD_fCost(withMoreLiterals), + newReps.rep[0], newReps.rep[1], newReps.rep[2] ); + opt[cur+1] = prevMatch; /* mlen & offbase */ + ZSTD_memcpy(opt[cur+1].rep, &newReps, sizeof(repcodes_t)); + opt[cur+1].litlen = 1; + opt[cur+1].price = with1literal; + if (last_pos < cur+1) last_pos = cur+1; + } + } } else { - DEBUGLOG(7, "cPos:%zi==rPos:%u : literal would cost more (%.2f>%.2f) (hist:%u,%u,%u)", - inr-istart, cur, ZSTD_fCost(price), ZSTD_fCost(opt[cur].price), - opt[cur].rep[0], opt[cur].rep[1], opt[cur].rep[2]); + DEBUGLOG(7, "cPos:%zi==rPos:%u : literal would cost more (%.2f>%.2f)", + inr-istart, cur, ZSTD_fCost(price), ZSTD_fCost(opt[cur].price)); } } - /* Set the repcodes of the current position. We must do it here - * because we rely on the repcodes of the 2nd to last sequence being - * correct to set the next chunks repcodes during the backward - * traversal. + /* Offset history is not updated during match comparison. + * Do it here, now that the match is selected and confirmed. */ ZSTD_STATIC_ASSERT(sizeof(opt[cur].rep) == sizeof(repcodes_t)); assert(cur >= opt[cur].mlen); - if (opt[cur].mlen != 0) { + if (opt[cur].litlen == 0) { + /* just finished a match => alter offset history */ U32 const prev = cur - opt[cur].mlen; - repcodes_t const newReps = ZSTD_newRep(opt[prev].rep, opt[cur].off, opt[cur].litlen==0); + repcodes_t const newReps = ZSTD_newRep(opt[prev].rep, opt[cur].off, opt[prev].litlen==0); ZSTD_memcpy(opt[cur].rep, &newReps, sizeof(repcodes_t)); - } else { - ZSTD_memcpy(opt[cur].rep, opt[cur - 1].rep, sizeof(repcodes_t)); } /* last match must start at a minimum distance of 8 from oend */ @@ -35604,15 +32766,14 @@ ZSTD_compressBlock_opt_generic(ZSTD_matchState_t* ms, if ( (optLevel==0) /*static_test*/ && (opt[cur+1].price <= opt[cur].price + (BITCOST_MULTIPLIER/2)) ) { - DEBUGLOG(7, "move to next rPos:%u : price is <=", cur+1); + DEBUGLOG(7, "skip current position : next rPos(%u) price is cheaper", cur+1); continue; /* skip unpromising positions; about ~+6% speed, -0.01 ratio */ } assert(opt[cur].price >= 0); - { U32 const ll0 = (opt[cur].mlen != 0); - U32 const litlen = (opt[cur].mlen == 0) ? opt[cur].litlen : 0; - U32 const previousPrice = (U32)opt[cur].price; - U32 const basePrice = previousPrice + ZSTD_litLengthPrice(0, optStatePtr, optLevel); + { U32 const ll0 = (opt[cur].litlen == 0); + int const previousPrice = opt[cur].price; + int const basePrice = previousPrice + LL_PRICE(0); U32 nbMatches = getAllMatches(matches, ms, &nextToUpdate3, inr, iend, opt[cur].rep, ll0, minMatch); U32 matchNb; @@ -35624,18 +32785,17 @@ ZSTD_compressBlock_opt_generic(ZSTD_matchState_t* ms, continue; } - { U32 const maxML = matches[nbMatches-1].len; - DEBUGLOG(7, "cPos:%zi==rPos:%u, found %u matches, of maxLength=%u", - inr-istart, cur, nbMatches, maxML); - - if ( (maxML > sufficient_len) - || (cur + maxML >= ZSTD_OPT_NUM) ) { - lastSequence.mlen = maxML; - lastSequence.off = matches[nbMatches-1].off; - lastSequence.litlen = litlen; - cur -= (opt[cur].mlen==0) ? opt[cur].litlen : 0; /* last sequence is actually only literals, fix cur to last match - note : may underflow, in which case, it's first sequence, and it's okay */ - last_pos = cur + ZSTD_totalLen(lastSequence); - if (cur > ZSTD_OPT_NUM) cur = 0; /* underflow => first match */ + { U32 const longestML = matches[nbMatches-1].len; + DEBUGLOG(7, "cPos:%zi==rPos:%u, found %u matches, of longest ML=%u", + inr-istart, cur, nbMatches, longestML); + + if ( (longestML > sufficient_len) + || (cur + longestML >= ZSTD_OPT_NUM) + || (ip + cur + longestML >= iend) ) { + lastStretch.mlen = longestML; + lastStretch.off = matches[nbMatches-1].off; + lastStretch.litlen = 0; + last_pos = cur + longestML; goto _shortestPath; } } @@ -35647,19 +32807,24 @@ ZSTD_compressBlock_opt_generic(ZSTD_matchState_t* ms, U32 mlen; DEBUGLOG(7, "testing match %u => offBase=%4u, mlen=%2u, llen=%2u", - matchNb, matches[matchNb].off, lastML, litlen); + matchNb, matches[matchNb].off, lastML, opt[cur].litlen); for (mlen = lastML; mlen >= startML; mlen--) { /* scan downward */ U32 const pos = cur + mlen; - int const price = (int)basePrice + (int)ZSTD_getMatchPrice(offset, mlen, optStatePtr, optLevel); + int const price = basePrice + (int)ZSTD_getMatchPrice(offset, mlen, optStatePtr, optLevel); if ((pos > last_pos) || (price < opt[pos].price)) { DEBUGLOG(7, "rPos:%u (ml=%2u) => new better price (%.2f<%.2f)", pos, mlen, ZSTD_fCost(price), ZSTD_fCost(opt[pos].price)); - while (last_pos < pos) { opt[last_pos+1].price = ZSTD_MAX_PRICE; last_pos++; } /* fill empty positions */ + while (last_pos < pos) { + /* fill empty positions, for future comparisons */ + last_pos++; + opt[last_pos].price = ZSTD_MAX_PRICE; + opt[last_pos].litlen = !0; /* just needs to be != 0, to mean "not an end of match" */ + } opt[pos].mlen = mlen; opt[pos].off = offset; - opt[pos].litlen = litlen; + opt[pos].litlen = 0; opt[pos].price = price; } else { DEBUGLOG(7, "rPos:%u (ml=%2u) => new price is worse (%.2f>=%.2f)", @@ -35667,43 +32832,77 @@ ZSTD_compressBlock_opt_generic(ZSTD_matchState_t* ms, if (optLevel==0) break; /* early update abort; gets ~+10% speed for about -0.01 ratio loss */ } } } } + opt[last_pos+1].price = ZSTD_MAX_PRICE; } /* for (cur = 1; cur <= last_pos; cur++) */ - lastSequence = opt[last_pos]; - cur = last_pos > ZSTD_totalLen(lastSequence) ? last_pos - ZSTD_totalLen(lastSequence) : 0; /* single sequence, and it starts before `ip` */ - assert(cur < ZSTD_OPT_NUM); /* control overflow*/ + lastStretch = opt[last_pos]; + assert(cur >= lastStretch.mlen); + cur = last_pos - lastStretch.mlen; _shortestPath: /* cur, last_pos, best_mlen, best_off have to be set */ assert(opt[0].mlen == 0); + assert(last_pos >= lastStretch.mlen); + assert(cur == last_pos - lastStretch.mlen); - /* Set the next chunk's repcodes based on the repcodes of the beginning - * of the last match, and the last sequence. This avoids us having to - * update them while traversing the sequences. - */ - if (lastSequence.mlen != 0) { - repcodes_t const reps = ZSTD_newRep(opt[cur].rep, lastSequence.off, lastSequence.litlen==0); - ZSTD_memcpy(rep, &reps, sizeof(reps)); - } else { - ZSTD_memcpy(rep, opt[cur].rep, sizeof(repcodes_t)); + if (lastStretch.mlen==0) { + /* no solution : all matches have been converted into literals */ + assert(lastStretch.litlen == (ip - anchor) + last_pos); + ip += last_pos; + continue; } + assert(lastStretch.off > 0); - { U32 const storeEnd = cur + 1; + /* Update offset history */ + if (lastStretch.litlen == 0) { + /* finishing on a match : update offset history */ + repcodes_t const reps = ZSTD_newRep(opt[cur].rep, lastStretch.off, opt[cur].litlen==0); + ZSTD_memcpy(rep, &reps, sizeof(repcodes_t)); + } else { + ZSTD_memcpy(rep, lastStretch.rep, sizeof(repcodes_t)); + assert(cur >= lastStretch.litlen); + cur -= lastStretch.litlen; + } + + /* Let's write the shortest path solution. + * It is stored in @opt in reverse order, + * starting from @storeEnd (==cur+2), + * effectively partially @opt overwriting. + * Content is changed too: + * - So far, @opt stored stretches, aka a match followed by literals + * - Now, it will store sequences, aka literals followed by a match + */ + { U32 const storeEnd = cur + 2; U32 storeStart = storeEnd; - U32 seqPos = cur; + U32 stretchPos = cur; DEBUGLOG(6, "start reverse traversal (last_pos:%u, cur:%u)", last_pos, cur); (void)last_pos; - assert(storeEnd < ZSTD_OPT_NUM); - DEBUGLOG(6, "last sequence copied into pos=%u (llen=%u,mlen=%u,ofc=%u)", - storeEnd, lastSequence.litlen, lastSequence.mlen, lastSequence.off); - opt[storeEnd] = lastSequence; - while (seqPos > 0) { - U32 const backDist = ZSTD_totalLen(opt[seqPos]); + assert(storeEnd < ZSTD_OPT_SIZE); + DEBUGLOG(6, "last stretch copied into pos=%u (llen=%u,mlen=%u,ofc=%u)", + storeEnd, lastStretch.litlen, lastStretch.mlen, lastStretch.off); + if (lastStretch.litlen > 0) { + /* last "sequence" is unfinished: just a bunch of literals */ + opt[storeEnd].litlen = lastStretch.litlen; + opt[storeEnd].mlen = 0; + storeStart = storeEnd-1; + opt[storeStart] = lastStretch; + } { + opt[storeEnd] = lastStretch; /* note: litlen will be fixed */ + storeStart = storeEnd; + } + while (1) { + ZSTD_optimal_t nextStretch = opt[stretchPos]; + opt[storeStart].litlen = nextStretch.litlen; + DEBUGLOG(6, "selected sequence (llen=%u,mlen=%u,ofc=%u)", + opt[storeStart].litlen, opt[storeStart].mlen, opt[storeStart].off); + if (nextStretch.mlen == 0) { + /* reaching beginning of segment */ + break; + } storeStart--; - DEBUGLOG(6, "sequence from rPos=%u copied into pos=%u (llen=%u,mlen=%u,ofc=%u)", - seqPos, storeStart, opt[seqPos].litlen, opt[seqPos].mlen, opt[seqPos].off); - opt[storeStart] = opt[seqPos]; - seqPos = (seqPos > backDist) ? seqPos - backDist : 0; + opt[storeStart] = nextStretch; /* note: litlen will be fixed */ + assert(nextStretch.litlen + nextStretch.mlen <= stretchPos); + stretchPos -= nextStretch.litlen + nextStretch.mlen; } /* save sequences */ @@ -35729,6 +32928,9 @@ ZSTD_compressBlock_opt_generic(ZSTD_matchState_t* ms, anchor += advance; ip = anchor; } } + DEBUGLOG(7, "new offset history : %u, %u, %u", rep[0], rep[1], rep[2]); + + /* update all costs */ ZSTD_setBasePrices(optStatePtr, optLevel); } } /* while (ip < ilimit) */ @@ -35824,7 +33026,7 @@ size_t ZSTD_compressBlock_btultra2( * Consequently, this can only work if no data has been previously loaded in tables, * aka, no dictionary, no prefix, no ldm preprocessing. * The compression ratio gain is generally small (~0.5% on first block), - ** the cost is 2x cpu time on first block. */ + * the cost is 2x cpu time on first block. */ assert(srcSize <= ZSTD_BLOCKSIZE_MAX); if ( (ms->opt.litLengthSum==0) /* first block */ && (seqStore->sequences == seqStore->sequencesStart) /* no ldm */ @@ -35984,10 +33186,10 @@ typedef struct ZSTDMT_bufferPool_s { static void ZSTDMT_freeBufferPool(ZSTDMT_bufferPool* bufPool) { - unsigned u; DEBUGLOG(3, "ZSTDMT_freeBufferPool (address:%08X)", (U32)(size_t)bufPool); if (!bufPool) return; /* compatibility with free on NULL */ if (bufPool->buffers) { + unsigned u; for (u=0; utotalBuffers; u++) { DEBUGLOG(4, "free buffer %2u (address:%08X)", u, (U32)(size_t)bufPool->buffers[u].start); ZSTD_customFree(bufPool->buffers[u].start, bufPool->cMem); @@ -36000,7 +33202,7 @@ static void ZSTDMT_freeBufferPool(ZSTDMT_bufferPool* bufPool) static ZSTDMT_bufferPool* ZSTDMT_createBufferPool(unsigned maxNbBuffers, ZSTD_customMem cMem) { - ZSTDMT_bufferPool* const bufPool = + ZSTDMT_bufferPool* const bufPool = (ZSTDMT_bufferPool*)ZSTD_customCalloc(sizeof(ZSTDMT_bufferPool), cMem); if (bufPool==NULL) return NULL; if (ZSTD_pthread_mutex_init(&bufPool->poolMutex, NULL)) { @@ -36243,10 +33445,10 @@ typedef struct { /* note : all CCtx borrowed from the pool must be reverted back to the pool _before_ freeing the pool */ static void ZSTDMT_freeCCtxPool(ZSTDMT_CCtxPool* pool) { - int cid; if (!pool) return; ZSTD_pthread_mutex_destroy(&pool->poolMutex); if (pool->cctxs) { + int cid; for (cid=0; cidtotalCCtx; cid++) ZSTD_freeCCtx(pool->cctxs[cid]); /* free compatible with NULL */ ZSTD_customFree(pool->cctxs, pool->cMem); @@ -36259,7 +33461,7 @@ static void ZSTDMT_freeCCtxPool(ZSTDMT_CCtxPool* pool) static ZSTDMT_CCtxPool* ZSTDMT_createCCtxPool(int nbWorkers, ZSTD_customMem cMem) { - ZSTDMT_CCtxPool* const cctxPool = + ZSTDMT_CCtxPool* const cctxPool = (ZSTDMT_CCtxPool*) ZSTD_customCalloc(sizeof(ZSTDMT_CCtxPool), cMem); assert(nbWorkers > 0); if (!cctxPool) return NULL; @@ -40298,14 +37500,16 @@ unsigned ZSTD_getDictID_fromDDict(const ZSTD_DDict* ddict) /*-******************************************************* * Dependencies *********************************************************/ -/**** skipping file: ../common/allocations.h ****/ /**** skipping file: ../common/zstd_deps.h ****/ +/**** skipping file: ../common/allocations.h ****/ +/**** skipping file: ../common/error_private.h ****/ +/**** skipping file: ../common/zstd_internal.h ****/ /**** skipping file: ../common/mem.h ****/ +/**** skipping file: ../common/bits.h ****/ #define FSE_STATIC_LINKING_ONLY /**** skipping file: ../common/fse.h ****/ /**** skipping file: ../common/huf.h ****/ /**** skipping file: ../common/xxhash.h ****/ -/**** skipping file: ../common/zstd_internal.h ****/ /**** skipping file: zstd_decompress_internal.h ****/ /**** skipping file: zstd_ddict.h ****/ /**** start inlining zstd_decompress_block.h ****/ @@ -40383,7 +37587,6 @@ size_t ZSTD_decompressBlock_deprecated(ZSTD_DCtx* dctx, #endif /* ZSTD_DEC_BLOCK_H */ /**** ended inlining zstd_decompress_block.h ****/ -/**** skipping file: ../common/bits.h ****/ #if defined(ZSTD_LEGACY_SUPPORT) && (ZSTD_LEGACY_SUPPORT>=1) #error Using excluded file: ../legacy/zstd_legacy.h (re-amalgamate source to fix) @@ -41045,17 +38248,17 @@ static ZSTD_frameSizeInfo ZSTD_errorFrameSizeInfo(size_t ret) return frameSizeInfo; } -static ZSTD_frameSizeInfo ZSTD_findFrameSizeInfo(const void* src, size_t srcSize) +static ZSTD_frameSizeInfo ZSTD_findFrameSizeInfo(const void* src, size_t srcSize, ZSTD_format_e format) { ZSTD_frameSizeInfo frameSizeInfo; ZSTD_memset(&frameSizeInfo, 0, sizeof(ZSTD_frameSizeInfo)); #if defined(ZSTD_LEGACY_SUPPORT) && (ZSTD_LEGACY_SUPPORT >= 1) - if (ZSTD_isLegacy(src, srcSize)) + if (format == ZSTD_f_zstd1 && ZSTD_isLegacy(src, srcSize)) return ZSTD_findFrameSizeInfoLegacy(src, srcSize); #endif - if ((srcSize >= ZSTD_SKIPPABLEHEADERSIZE) + if (format == ZSTD_f_zstd1 && (srcSize >= ZSTD_SKIPPABLEHEADERSIZE) && (MEM_readLE32(src) & ZSTD_MAGIC_SKIPPABLE_MASK) == ZSTD_MAGIC_SKIPPABLE_START) { frameSizeInfo.compressedSize = readSkippableFrameSize(src, srcSize); assert(ZSTD_isError(frameSizeInfo.compressedSize) || @@ -41069,7 +38272,7 @@ static ZSTD_frameSizeInfo ZSTD_findFrameSizeInfo(const void* src, size_t srcSize ZSTD_frameHeader zfh; /* Extract Frame Header */ - { size_t const ret = ZSTD_getFrameHeader(&zfh, src, srcSize); + { size_t const ret = ZSTD_getFrameHeader_advanced(&zfh, src, srcSize, format); if (ZSTD_isError(ret)) return ZSTD_errorFrameSizeInfo(ret); if (ret > 0) @@ -41112,15 +38315,17 @@ static ZSTD_frameSizeInfo ZSTD_findFrameSizeInfo(const void* src, size_t srcSize } } +static size_t ZSTD_findFrameCompressedSize_advanced(const void *src, size_t srcSize, ZSTD_format_e format) { + ZSTD_frameSizeInfo const frameSizeInfo = ZSTD_findFrameSizeInfo(src, srcSize, format); + return frameSizeInfo.compressedSize; +} + /** ZSTD_findFrameCompressedSize() : - * compatible with legacy mode - * `src` must point to the start of a ZSTD frame, ZSTD legacy frame, or skippable frame - * `srcSize` must be at least as large as the frame contained - * @return : the compressed size of the frame starting at `src` */ + * See docs in zstd.h + * Note: compatible with legacy mode */ size_t ZSTD_findFrameCompressedSize(const void *src, size_t srcSize) { - ZSTD_frameSizeInfo const frameSizeInfo = ZSTD_findFrameSizeInfo(src, srcSize); - return frameSizeInfo.compressedSize; + return ZSTD_findFrameCompressedSize_advanced(src, srcSize, ZSTD_f_zstd1); } /** ZSTD_decompressBound() : @@ -41134,7 +38339,7 @@ unsigned long long ZSTD_decompressBound(const void* src, size_t srcSize) unsigned long long bound = 0; /* Iterate over each frame */ while (srcSize > 0) { - ZSTD_frameSizeInfo const frameSizeInfo = ZSTD_findFrameSizeInfo(src, srcSize); + ZSTD_frameSizeInfo const frameSizeInfo = ZSTD_findFrameSizeInfo(src, srcSize, ZSTD_f_zstd1); size_t const compressedSize = frameSizeInfo.compressedSize; unsigned long long const decompressedBound = frameSizeInfo.decompressedBound; if (ZSTD_isError(compressedSize) || decompressedBound == ZSTD_CONTENTSIZE_ERROR) @@ -41154,7 +38359,7 @@ size_t ZSTD_decompressionMargin(void const* src, size_t srcSize) /* Iterate over each frame */ while (srcSize > 0) { - ZSTD_frameSizeInfo const frameSizeInfo = ZSTD_findFrameSizeInfo(src, srcSize); + ZSTD_frameSizeInfo const frameSizeInfo = ZSTD_findFrameSizeInfo(src, srcSize, ZSTD_f_zstd1); size_t const compressedSize = frameSizeInfo.compressedSize; unsigned long long const decompressedBound = frameSizeInfo.decompressedBound; ZSTD_frameHeader zfh; @@ -41340,12 +38545,14 @@ static size_t ZSTD_decompressFrame(ZSTD_DCtx* dctx, default: RETURN_ERROR(corruption_detected, "invalid block type"); } - - if (ZSTD_isError(decodedSize)) return decodedSize; - if (dctx->validateChecksum) + FORWARD_IF_ERROR(decodedSize, "Block decompression failure"); + DEBUGLOG(5, "Decompressed block of dSize = %u", (unsigned)decodedSize); + if (dctx->validateChecksum) { XXH64_update(&dctx->xxhState, op, decodedSize); - if (decodedSize != 0) + } + if (decodedSize) /* support dst = NULL,0 */ { op += decodedSize; + } assert(ip != NULL); ip += cBlockSize; remainingSrcSize -= cBlockSize; @@ -41397,7 +38604,7 @@ size_t ZSTD_decompressMultiFrame(ZSTD_DCtx* dctx, while (srcSize >= ZSTD_startingInputLength(dctx->format)) { #if defined(ZSTD_LEGACY_SUPPORT) && (ZSTD_LEGACY_SUPPORT >= 1) - if (ZSTD_isLegacy(src, srcSize)) { + if (dctx->format == ZSTD_f_zstd1 && ZSTD_isLegacy(src, srcSize)) { size_t decodedSize; size_t const frameSize = ZSTD_findFrameCompressedSizeLegacy(src, srcSize); if (ZSTD_isError(frameSize)) return frameSize; @@ -41407,6 +38614,15 @@ size_t ZSTD_decompressMultiFrame(ZSTD_DCtx* dctx, decodedSize = ZSTD_decompressLegacy(dst, dstCapacity, src, frameSize, dict, dictSize); if (ZSTD_isError(decodedSize)) return decodedSize; + { + unsigned long long const expectedSize = ZSTD_getFrameContentSize(src, srcSize); + RETURN_ERROR_IF(expectedSize == ZSTD_CONTENTSIZE_ERROR, corruption_detected, "Corrupted frame header!"); + if (expectedSize != ZSTD_CONTENTSIZE_UNKNOWN) { + RETURN_ERROR_IF(expectedSize != decodedSize, corruption_detected, + "Frame header size does not match decoded size!"); + } + } + assert(decodedSize <= dstCapacity); dst = (BYTE*)dst + decodedSize; dstCapacity -= decodedSize; @@ -41418,7 +38634,7 @@ size_t ZSTD_decompressMultiFrame(ZSTD_DCtx* dctx, } #endif - if (srcSize >= 4) { + if (dctx->format == ZSTD_f_zstd1 && srcSize >= 4) { U32 const magicNumber = MEM_readLE32(src); DEBUGLOG(5, "reading magic number %08X", (unsigned)magicNumber); if ((magicNumber & ZSTD_MAGIC_SKIPPABLE_MASK) == ZSTD_MAGIC_SKIPPABLE_START) { @@ -41715,6 +38931,7 @@ size_t ZSTD_decompressContinue(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, c case ZSTDds_decodeSkippableHeader: assert(src != NULL); assert(srcSize <= ZSTD_SKIPPABLEHEADERSIZE); + assert(dctx->format != ZSTD_f_zstd1_magicless); ZSTD_memcpy(dctx->headerBuffer + (ZSTD_SKIPPABLEHEADERSIZE - srcSize), src, srcSize); /* complete skippable header */ dctx->expected = MEM_readLE32(dctx->headerBuffer + ZSTD_FRAMEIDSIZE); /* note : dctx->expected can grow seriously large, beyond local buffer size */ dctx->stage = ZSTDds_skipFrame; @@ -42485,7 +39702,7 @@ size_t ZSTD_decompressStream(ZSTD_DStream* zds, ZSTD_outBuffer* output, ZSTD_inB if (zds->fParams.frameContentSize != ZSTD_CONTENTSIZE_UNKNOWN && zds->fParams.frameType != ZSTD_skippableFrame && (U64)(size_t)(oend-op) >= zds->fParams.frameContentSize) { - size_t const cSize = ZSTD_findFrameCompressedSize(istart, (size_t)(iend-istart)); + size_t const cSize = ZSTD_findFrameCompressedSize_advanced(istart, (size_t)(iend-istart), zds->format); if (cSize <= (size_t)(iend-istart)) { /* shortcut : using single-pass mode */ size_t const decompressedSize = ZSTD_decompress_usingDDict(zds, op, (size_t)(oend-op), istart, cSize, ZSTD_getDDict(zds)); @@ -42512,7 +39729,8 @@ size_t ZSTD_decompressStream(ZSTD_DStream* zds, ZSTD_outBuffer* output, ZSTD_inB DEBUGLOG(4, "Consume header"); FORWARD_IF_ERROR(ZSTD_decompressBegin_usingDDict(zds, ZSTD_getDDict(zds)), ""); - if ((MEM_readLE32(zds->headerBuffer) & ZSTD_MAGIC_SKIPPABLE_MASK) == ZSTD_MAGIC_SKIPPABLE_START) { /* skippable frame */ + if (zds->format == ZSTD_f_zstd1 + && (MEM_readLE32(zds->headerBuffer) & ZSTD_MAGIC_SKIPPABLE_MASK) == ZSTD_MAGIC_SKIPPABLE_START) { /* skippable frame */ zds->expected = MEM_readLE32(zds->headerBuffer + ZSTD_FRAMEIDSIZE); zds->stage = ZSTDds_skipFrame; } else { @@ -43437,6 +40655,7 @@ size_t ZSTD_decodeSeqHeaders(ZSTD_DCtx* dctx, int* nbSeqPtr, /* FSE table descriptors */ RETURN_ERROR_IF(ip+1 > iend, srcSize_wrong, ""); /* minimum possible size: 1 byte for symbol encoding types */ + RETURN_ERROR_IF(*ip & 3, corruption_detected, ""); /* The last field, Reserved, must be all-zeroes. */ { symbolEncodingType_e const LLtype = (symbolEncodingType_e)(*ip >> 6); symbolEncodingType_e const OFtype = (symbolEncodingType_e)((*ip >> 4) & 3); symbolEncodingType_e const MLtype = (symbolEncodingType_e)((*ip >> 2) & 3); @@ -44014,7 +41233,7 @@ ZSTD_decodeSequence(seqState_t* seqState, const ZSTD_longOffset_e longOffsets, c } else { offset = ofBase + ll0 + BIT_readBitsFast(&seqState->DStream, 1); { size_t temp = (offset==3) ? seqState->prevOffset[0] - 1 : seqState->prevOffset[offset]; - temp += !temp; /* 0 is not valid; input is corrupted; force offset to 1 */ + temp -= !temp; /* 0 is not valid: input corrupted => force offset to -1 => corruption detected at execSequence */ if (offset != 1) seqState->prevOffset[2] = seqState->prevOffset[1]; seqState->prevOffset[1] = seqState->prevOffset[0]; seqState->prevOffset[0] = offset = temp; @@ -44295,7 +41514,8 @@ ZSTD_decompressSequences_bodySplitLitBuffer( ZSTD_DCtx* dctx, /* last literal segment */ if (dctx->litBufferLocation == ZSTD_split) { /* split hasn't been reached yet, first get dst then copy litExtraBuffer */ - size_t const lastLLSize = litBufferEnd - litPtr; + size_t const lastLLSize = (size_t)(litBufferEnd - litPtr); + DEBUGLOG(6, "copy last literals from segment : %u", (U32)lastLLSize); RETURN_ERROR_IF(lastLLSize > (size_t)(oend - op), dstSize_tooSmall, ""); if (op != NULL) { ZSTD_memmove(op, litPtr, lastLLSize); @@ -44306,14 +41526,16 @@ ZSTD_decompressSequences_bodySplitLitBuffer( ZSTD_DCtx* dctx, dctx->litBufferLocation = ZSTD_not_in_dst; } /* copy last literals from internal buffer */ - { size_t const lastLLSize = litBufferEnd - litPtr; + { size_t const lastLLSize = (size_t)(litBufferEnd - litPtr); + DEBUGLOG(6, "copy last literals from internal buffer : %u", (U32)lastLLSize); RETURN_ERROR_IF(lastLLSize > (size_t)(oend-op), dstSize_tooSmall, ""); if (op != NULL) { ZSTD_memcpy(op, litPtr, lastLLSize); op += lastLLSize; } } - return op-ostart; + DEBUGLOG(6, "decoded block of size %u bytes", (U32)(op - ostart)); + return (size_t)(op - ostart); } FORCE_INLINE_TEMPLATE size_t @@ -44383,14 +41605,16 @@ ZSTD_decompressSequences_body(ZSTD_DCtx* dctx, } /* last literal segment */ - { size_t const lastLLSize = litEnd - litPtr; + { size_t const lastLLSize = (size_t)(litEnd - litPtr); + DEBUGLOG(6, "copy last literals : %u", (U32)lastLLSize); RETURN_ERROR_IF(lastLLSize > (size_t)(oend-op), dstSize_tooSmall, ""); if (op != NULL) { ZSTD_memcpy(op, litPtr, lastLLSize); op += lastLLSize; } } - return op-ostart; + DEBUGLOG(6, "decoded block of size %u bytes", (U32)(op - ostart)); + return (size_t)(op - ostart); } static size_t @@ -44588,7 +41812,7 @@ ZSTD_decompressSequencesLong_body( } } - return op-ostart; + return (size_t)(op - ostart); } static size_t @@ -44778,7 +42002,7 @@ ZSTD_decompressBlock_internal(ZSTD_DCtx* dctx, const void* src, size_t srcSize, const streaming_operation streaming) { /* blockType == blockCompressed */ const BYTE* ip = (const BYTE*)src; - DEBUGLOG(5, "ZSTD_decompressBlock_internal (size : %u)", (U32)srcSize); + DEBUGLOG(5, "ZSTD_decompressBlock_internal (cSize : %u)", (unsigned)srcSize); /* Note : the wording of the specification * allows compressed block to be sized exactly ZSTD_blockSizeMax(dctx). @@ -45448,14 +42672,8 @@ size_t ZDICT_addEntropyTablesFromBuffer(void* dictBuffer, size_t dictContentSize # define ZDICT_STATIC_LINKING_ONLY #endif -#include /* fprintf */ -#include /* malloc, free, qsort */ -#include /* memset */ -#include /* clock */ -/**** skipping file: ../common/mem.h ****/ -/**** skipping file: ../common/pool.h ****/ /**** skipping file: ../common/threading.h ****/ -/**** skipping file: ../common/zstd_internal.h ****/ +/**** skipping file: ../common/mem.h ****/ /**** skipping file: ../zdict.h ****/ /** @@ -45634,7 +42852,7 @@ static clock_t g_time = 0; #undef LOCALDISPLAYUPDATE #define LOCALDISPLAYUPDATE(displayLevel, l, ...) \ if (displayLevel >= l) { \ - if ((clock() - g_time > g_refreshRate) || (displayLevel >= 4)) { \ + if ((clock() - g_time > g_refreshRate) || (displayLevel >= 4)) { \ g_time = clock(); \ DISPLAY(__VA_ARGS__); \ } \ @@ -45857,9 +43075,10 @@ static int WIN_CDECL COVER_strict_cmp8(const void *lp, const void *rp) { * Returns the first pointer in [first, last) whose element does not compare * less than value. If no such element exists it returns last. */ -static const size_t *COVER_lower_bound(const size_t *first, const size_t *last, +static const size_t *COVER_lower_bound(const size_t* first, const size_t* last, size_t value) { - size_t count = last - first; + size_t count = (size_t)(last - first); + assert(last >= first); while (count != 0) { size_t step = count / 2; const size_t *ptr = first; @@ -46105,7 +43324,8 @@ static void COVER_ctx_destroy(COVER_ctx_t *ctx) { */ static size_t COVER_ctx_init(COVER_ctx_t *ctx, const void *samplesBuffer, const size_t *samplesSizes, unsigned nbSamples, - unsigned d, double splitPoint) { + unsigned d, double splitPoint) +{ const BYTE *const samples = (const BYTE *)samplesBuffer; const size_t totalSamplesSize = COVER_sum(samplesSizes, nbSamples); /* Split samples into testing and training sets */ @@ -46463,8 +43683,10 @@ void COVER_best_start(COVER_best_t *best) { * Decrements liveJobs and signals any waiting threads if liveJobs == 0. * If this dictionary is the best so far save it and its parameters. */ -void COVER_best_finish(COVER_best_t *best, ZDICT_cover_params_t parameters, - COVER_dictSelection_t selection) { +void COVER_best_finish(COVER_best_t* best, + ZDICT_cover_params_t parameters, + COVER_dictSelection_t selection) +{ void* dict = selection.dictContent; size_t compressedSize = selection.totalCompressedSize; size_t dictSize = selection.dictSize; @@ -46536,8 +43758,8 @@ COVER_dictSelection_t COVER_selectDict(BYTE* customDictContent, size_t dictBuffe size_t largestCompressed = 0; BYTE* customDictContentEnd = customDictContent + dictContentSize; - BYTE * largestDictbuffer = (BYTE *)malloc(dictBufferCapacity); - BYTE * candidateDictBuffer = (BYTE *)malloc(dictBufferCapacity); + BYTE* largestDictbuffer = (BYTE*)malloc(dictBufferCapacity); + BYTE* candidateDictBuffer = (BYTE*)malloc(dictBufferCapacity); double regressionTolerance = ((double)params.shrinkDictMaxRegression / 100.0) + 1.00; if (!largestDictbuffer || !candidateDictBuffer) { diff --git a/thirdparty/zstd/zstd.h b/thirdparty/zstd/zstd.h new file mode 100644 index 00000000000000..48a13aaa82b15b --- /dev/null +++ b/thirdparty/zstd/zstd.h @@ -0,0 +1,3090 @@ +/* + * Copyright (c) Meta Platforms, Inc. and affiliates. + * All rights reserved. + * + * This source code is licensed under both the BSD-style license (found in the + * LICENSE file in the root directory of this source tree) and the GPLv2 (found + * in the COPYING file in the root directory of this source tree). + * You may select, at your option, one of the above-listed licenses. + */ +#if defined (__cplusplus) +extern "C" { +#endif + +#ifndef ZSTD_H_235446 +#define ZSTD_H_235446 + +/* ====== Dependencies ======*/ +#include /* INT_MAX */ +#include /* size_t */ + + +/* ===== ZSTDLIB_API : control library symbols visibility ===== */ +#ifndef ZSTDLIB_VISIBLE + /* Backwards compatibility with old macro name */ +# ifdef ZSTDLIB_VISIBILITY +# define ZSTDLIB_VISIBLE ZSTDLIB_VISIBILITY +# elif defined(__GNUC__) && (__GNUC__ >= 4) && !defined(__MINGW32__) +# define ZSTDLIB_VISIBLE __attribute__ ((visibility ("default"))) +# else +# define ZSTDLIB_VISIBLE +# endif +#endif + +#ifndef ZSTDLIB_HIDDEN +# if defined(__GNUC__) && (__GNUC__ >= 4) && !defined(__MINGW32__) +# define ZSTDLIB_HIDDEN __attribute__ ((visibility ("hidden"))) +# else +# define ZSTDLIB_HIDDEN +# endif +#endif + +#if defined(ZSTD_DLL_EXPORT) && (ZSTD_DLL_EXPORT==1) +# define ZSTDLIB_API __declspec(dllexport) ZSTDLIB_VISIBLE +#elif defined(ZSTD_DLL_IMPORT) && (ZSTD_DLL_IMPORT==1) +# define ZSTDLIB_API __declspec(dllimport) ZSTDLIB_VISIBLE /* It isn't required but allows to generate better code, saving a function pointer load from the IAT and an indirect jump.*/ +#else +# define ZSTDLIB_API ZSTDLIB_VISIBLE +#endif + +/* Deprecation warnings : + * Should these warnings be a problem, it is generally possible to disable them, + * typically with -Wno-deprecated-declarations for gcc or _CRT_SECURE_NO_WARNINGS in Visual. + * Otherwise, it's also possible to define ZSTD_DISABLE_DEPRECATE_WARNINGS. + */ +#ifdef ZSTD_DISABLE_DEPRECATE_WARNINGS +# define ZSTD_DEPRECATED(message) /* disable deprecation warnings */ +#else +# if defined (__cplusplus) && (__cplusplus >= 201402) /* C++14 or greater */ +# define ZSTD_DEPRECATED(message) [[deprecated(message)]] +# elif (defined(GNUC) && (GNUC > 4 || (GNUC == 4 && GNUC_MINOR >= 5))) || defined(__clang__) +# define ZSTD_DEPRECATED(message) __attribute__((deprecated(message))) +# elif defined(__GNUC__) && (__GNUC__ >= 3) +# define ZSTD_DEPRECATED(message) __attribute__((deprecated)) +# elif defined(_MSC_VER) +# define ZSTD_DEPRECATED(message) __declspec(deprecated(message)) +# else +# pragma message("WARNING: You need to implement ZSTD_DEPRECATED for this compiler") +# define ZSTD_DEPRECATED(message) +# endif +#endif /* ZSTD_DISABLE_DEPRECATE_WARNINGS */ + + +/******************************************************************************* + 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). + + 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: + - a single step (described as Simple 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. +*******************************************************************************/ + +/*------ Version ------*/ +#define ZSTD_VERSION_MAJOR 1 +#define ZSTD_VERSION_MINOR 5 +#define ZSTD_VERSION_RELEASE 6 +#define ZSTD_VERSION_NUMBER (ZSTD_VERSION_MAJOR *100*100 + ZSTD_VERSION_MINOR *100 + ZSTD_VERSION_RELEASE) + +/*! ZSTD_versionNumber() : + * Return runtime library version, the value is (MAJOR*100*100 + MINOR*100 + RELEASE). */ +ZSTDLIB_API unsigned ZSTD_versionNumber(void); + +#define ZSTD_LIB_VERSION ZSTD_VERSION_MAJOR.ZSTD_VERSION_MINOR.ZSTD_VERSION_RELEASE +#define ZSTD_QUOTE(str) #str +#define ZSTD_EXPAND_AND_QUOTE(str) ZSTD_QUOTE(str) +#define ZSTD_VERSION_STRING ZSTD_EXPAND_AND_QUOTE(ZSTD_LIB_VERSION) + +/*! ZSTD_versionString() : + * Return runtime library version, like "1.4.5". Requires v1.3.0+. */ +ZSTDLIB_API const char* ZSTD_versionString(void); + +/* ************************************* + * Default constant + ***************************************/ +#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_compressBound(srcSize)` guarantees that zstd will have + * enough space to successfully compress the data. + * @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_compress( void* dst, size_t dstCapacity, + const void* src, size_t srcSize, + int compressionLevel); + +/*! ZSTD_decompress() : + * `compressedSize` : must be the _exact_ size of some number of compressed and/or skippable frames. + * `dstCapacity` is an upper bound of originalSize to regenerate. + * If user cannot imply a maximum upper bound, it's better to use streaming mode to decompress data. + * @return : the number of bytes decompressed into `dst` (<= `dstCapacity`), + * or an errorCode if it fails (which can be tested using ZSTD_isError()). */ +ZSTDLIB_API size_t ZSTD_decompress( void* dst, size_t dstCapacity, + const void* src, size_t compressedSize); + +/*! 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 + * - 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". + * note 2 : decompressed size is an optional field, it may not be present, typically in streaming mode. + * When `return==ZSTD_CONTENTSIZE_UNKNOWN`, data to decompress could be any size. + * In which case, it's necessary to use streaming mode to decompress data. + * 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 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. + * note 5 : If source is untrusted, decompressed size could be wrong or intentionally modified. + * Always ensure return value fits within application's authorized limits. + * Each application can set its own limits. + * note 6 : This function replaces ZSTD_getDecompressedSize() */ +#define ZSTD_CONTENTSIZE_UNKNOWN (0ULL - 1) +#define ZSTD_CONTENTSIZE_ERROR (0ULL - 2) +ZSTDLIB_API unsigned long long ZSTD_getFrameContentSize(const void *src, size_t srcSize); + +/*! ZSTD_getDecompressedSize() : + * NOTE: This function is now obsolete, in favor of ZSTD_getFrameContentSize(). + * 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. */ +ZSTD_DEPRECATED("Replaced by ZSTD_getFrameContentSize") +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); + + +/*====== Helper functions ======*/ +/* ZSTD_compressBound() : + * maximum compressed size in worst case single-pass scenario. + * When invoking `ZSTD_compress()` or any other one-pass compression function, + * it's recommended to provide @dstCapacity >= ZSTD_compressBound(srcSize) + * as it eliminates one potential failure scenario, + * aka not enough room in dst buffer to write the compressed frame. + * Note : ZSTD_compressBound() itself can fail, if @srcSize > ZSTD_MAX_INPUT_SIZE . + * In which case, ZSTD_compressBound() will return an error code + * which can be tested using ZSTD_isError(). + * + * ZSTD_COMPRESSBOUND() : + * same as ZSTD_compressBound(), but as a macro. + * It can be used to produce constants, which can be useful for static allocation, + * for example to size a static array on stack. + * Will produce constant value 0 if srcSize too large. + */ +#define ZSTD_MAX_INPUT_SIZE ((sizeof(size_t)==8) ? 0xFF00FF00FF00FF00ULL : 0xFF00FF00U) +#define ZSTD_COMPRESSBOUND(srcSize) (((size_t)(srcSize) >= ZSTD_MAX_INPUT_SIZE) ? 0 : (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 */ +/* ZSTD_isError() : + * Most ZSTD_* functions returning a size_t value can be tested for error, + * using ZSTD_isError(). + * @return 1 if error, 0 otherwise + */ +ZSTDLIB_API unsigned ZSTD_isError(size_t code); /*!< tells if a `size_t` function result is an error code */ +ZSTDLIB_API const char* ZSTD_getErrorName(size_t code); /*!< provides readable string from an error code */ +ZSTDLIB_API int ZSTD_minCLevel(void); /*!< minimum negative compression level allowed, requires v1.4.0+ */ +ZSTDLIB_API int ZSTD_maxCLevel(void); /*!< maximum compression level available */ +ZSTDLIB_API int ZSTD_defaultCLevel(void); /*!< default compression level, specified by ZSTD_CLEVEL_DEFAULT, requires v1.5.0+ */ + + +/*************************************** +* Explicit context +***************************************/ +/*= Compression context + * When compressing many times, + * it is recommended to allocate a context just once, + * and reuse it for each successive compression operation. + * This will make workload friendlier for system's memory. + * Note : re-using context is just a speed / resource optimization. + * It doesn't change the compression ratio, which remains identical. + * Note 2 : In multi-threaded environments, + * use one different context per thread for parallel execution. + */ +typedef struct ZSTD_CCtx_s ZSTD_CCtx; +ZSTDLIB_API ZSTD_CCtx* ZSTD_createCCtx(void); +ZSTDLIB_API size_t ZSTD_freeCCtx(ZSTD_CCtx* cctx); /* accept NULL pointer */ + +/*! ZSTD_compressCCtx() : + * Same as ZSTD_compress(), using an explicit ZSTD_CCtx. + * Important : in order to mirror `ZSTD_compress()` behavior, + * this function compresses at the requested compression level, + * __ignoring any other advanced parameter__ . + * 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, + void* dst, size_t dstCapacity, + const void* src, size_t srcSize, + int compressionLevel); + +/*= Decompression context + * When decompressing many times, + * it is recommended to allocate a context only once, + * and reuse it for each successive compression operation. + * This will make workload friendlier for system's memory. + * Use one context per thread for parallel execution. */ +typedef struct ZSTD_DCtx_s ZSTD_DCtx; +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 (see below). + */ +ZSTDLIB_API size_t ZSTD_decompressDCtx(ZSTD_DCtx* dctx, + void* dst, size_t dstCapacity, + const void* src, size_t srcSize); + + +/********************************************* +* 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*()` ! + * __They do not apply to one-shot variants such as ZSTD_compressCCtx()__ . + * + * 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 API entry points from experimental 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. + * 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 + * ones will 'stick'. */ + /* 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. + * 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 + * 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. + * 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. + * 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". */ + + ZSTD_c_targetCBlockSize=130, /* v1.5.6+ + * Attempts to fit compressed block size into approximatively targetCBlockSize. + * Bound by ZSTD_TARGETCBLOCKSIZE_MIN and ZSTD_TARGETCBLOCKSIZE_MAX. + * Note that it's not a guarantee, just a convergence target (default:0). + * No target when targetCBlockSize == 0. + * This is helpful in low bandwidth streaming environments to improve end-to-end latency, + * when a client can make use of partial documents (a prominent example being Chrome). + * Note: this parameter is stable since v1.5.6. + * It was present as an experimental parameter in earlier versions, + * but it's not recommended using it with earlier library versions + * due to massive performance regressions. + */ + /* 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(), + * 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) */ + + /* 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. + * 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, + * 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. + * 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. + * 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_srcSizeHint + * ZSTD_c_enableDedicatedDictSearch + * ZSTD_c_stableInBuffer + * ZSTD_c_stableOutBuffer + * ZSTD_c_blockDelimiters + * ZSTD_c_validateSequences + * ZSTD_c_useBlockSplitter + * ZSTD_c_useRowMatchFinder + * ZSTD_c_prefetchCDictTables + * ZSTD_c_enableSeqProducerFallback + * ZSTD_c_maxBlockSize + * 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, + /* was ZSTD_c_experimentalParam6=1003; is now ZSTD_c_targetCBlockSize */ + ZSTD_c_experimentalParam7=1004, + ZSTD_c_experimentalParam8=1005, + ZSTD_c_experimentalParam9=1006, + ZSTD_c_experimentalParam10=1007, + ZSTD_c_experimentalParam11=1008, + ZSTD_c_experimentalParam12=1009, + ZSTD_c_experimentalParam13=1010, + ZSTD_c_experimentalParam14=1011, + ZSTD_c_experimentalParam15=1012, + ZSTD_c_experimentalParam16=1013, + ZSTD_c_experimentalParam17=1014, + ZSTD_c_experimentalParam18=1015, + ZSTD_c_experimentalParam19=1016 +} 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 also removes any reference to any dictionary or external sequence producer. + * 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. + * (note that this entry point doesn't even expose a compression level parameter). + * 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. + * NOTE: Providing `dstCapacity >= ZSTD_compressBound(srcSize)` guarantees that zstd will have + * enough space to successfully compress the data, though it is possible it fails for other reasons. + * @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 : + * ZSTD_d_format + * ZSTD_d_stableOutBuffer + * ZSTD_d_forceIgnoreChecksum + * ZSTD_d_refMultipleDDicts + * ZSTD_d_disableHuffmanAssembly + * ZSTD_d_maxBlockSize + * 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_d_experimentalParam5=1004, + ZSTD_d_experimentalParam6=1005 + +} 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 +****************************/ + +typedef struct ZSTD_inBuffer_s { + const void* src; /**< start of input buffer */ + size_t size; /**< size of input buffer */ + size_t pos; /**< position where reading stopped. Will be updated. Necessarily 0 <= pos <= size */ +} ZSTD_inBuffer; + +typedef struct ZSTD_outBuffer_s { + void* dst; /**< start of output buffer */ + size_t size; /**< size of output buffer */ + size_t pos; /**< position where writing stopped. Will be updated. Necessarily 0 <= pos <= size */ +} ZSTD_outBuffer; + + + +/*-*********************************************************************** +* Streaming compression - HowTo +* +* 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 reuse 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. +* +* note : since v1.3.0, ZSTD_CStream and ZSTD_CCtx are the same thing. +* +* Parameters are sticky : when starting a new compression on the same context, +* it will reuse 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. +* 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. +* @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), +* 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 */ +/*===== 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; + +/*! 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. + * - endOp must be a valid directive + * - 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. + * - note: if an operation ends with an error, it may leave @cctx in an undefined state. + * Therefore, it's UB to invoke ZSTD_compressStream2() of ZSTD_compressStream() on such a state. + * In order to be re-employed after an error, a state must be reset, + * which can be done explicitly (ZSTD_CCtx_reset()), + * or is sometimes implied by methods starting a new compression job (ZSTD_initCStream(), ZSTD_compressCCtx()) + */ +ZSTDLIB_API size_t ZSTD_compressStream2( ZSTD_CCtx* cctx, + ZSTD_outBuffer* output, + ZSTD_inBuffer* input, + ZSTD_EndDirective endOp); + + +/* These buffer sizes are softly recommended. + * They are not required : ZSTD_compressStream*() happily accepts any buffer size, for both input and output. + * Respecting the recommended size just makes it a bit easier for ZSTD_compressStream*(), + * reducing the amount of memory shuffling and buffering, resulting in minor performance savings. + * + * However, note that these recommendations are from the perspective of a C caller program. + * If the streaming interface is invoked from some other language, + * especially managed ones such as Java or Go, through a foreign function interface such as jni or cgo, + * a major performance rule is to reduce crossing such interface to an absolute minimum. + * It's not rare that performance ends being spent more into the interface, rather than compression itself. + * In which cases, prefer using large buffers, as large as practical, + * for both input and output, to reduce the nb of roundtrips. + */ +ZSTDLIB_API size_t ZSTD_CStreamInSize(void); /**< recommended size for input buffer */ +ZSTDLIB_API size_t ZSTD_CStreamOutSize(void); /**< recommended size for output buffer. Guarantee to successfully flush at least one complete compressed block. */ + + +/* ***************************************************************************** + * This following is a legacy streaming API, available since v1.0+ . + * It can be replaced by ZSTD_CCtx_reset() and ZSTD_compressStream2(). + * It is redundant, but remains fully supported. + ******************************************************************************/ + +/*! + * 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); + * + * Note that ZSTD_initCStream() clears any previously set dictionary. Use the new API + * to compress with a dictionary. + */ +ZSTDLIB_API size_t ZSTD_initCStream(ZSTD_CStream* zcs, int compressionLevel); +/*! + * Alternative for ZSTD_compressStream2(zcs, output, input, ZSTD_e_continue). + * NOTE: The return value is different. ZSTD_compressStream() returns a hint for + * the next read size (if non-zero and not an error). ZSTD_compressStream2() + * returns the 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); +/*! Equivalent to ZSTD_compressStream2(zcs, output, &emptyInput, ZSTD_e_end). */ +ZSTDLIB_API size_t ZSTD_endStream(ZSTD_CStream* zcs, ZSTD_outBuffer* output); + + +/*-*************************************************************************** +* Streaming decompression - HowTo +* +* A ZSTD_DStream object is required to track streaming operations. +* Use ZSTD_createDStream() and ZSTD_freeDStream() to create/release resources. +* ZSTD_DStream objects can be reused 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_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. +* 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. +* *******************************************************************************/ + +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. */ +/*===== 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 =====*/ + +/*! ZSTD_initDStream() : + * Initialize/reset DStream state for new decompression operation. + * Call before new decompression operation using same DStream. + * + * Note : This function is redundant with the advanced API and equivalent to: + * ZSTD_DCtx_reset(zds, ZSTD_reset_session_only); + * ZSTD_DCtx_refDDict(zds, NULL); + */ +ZSTDLIB_API size_t ZSTD_initDStream(ZSTD_DStream* zds); + +/*! ZSTD_decompressStream() : + * Streaming decompression function. + * Call repetitively to consume full input updating it as necessary. + * Function will update both input and output `pos` fields exposing current state via these fields: + * - `input.pos < input.size`, some input remaining and caller should provide remaining input + * on the next call. + * - `output.pos < output.size`, decoder finished and flushed all remaining buffers. + * - `output.pos == output.size`, potentially uncflushed data present in the internal buffers, + * call ZSTD_decompressStream() again to flush remaining data to output. + * Note : with no additional input, amount of data flushed <= 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 some decoding or flushing to do to complete current frame. + * + * Note: when an operation returns with an error code, the @zds state may be left in undefined state. + * It's UB to invoke `ZSTD_decompressStream()` on such a state. + * In order to re-use such a state, it must be first reset, + * which can be done explicitly (`ZSTD_DCtx_reset()`), + * or is implied for operations starting some new decompression job (`ZSTD_initDStream`, `ZSTD_decompressDCtx()`, `ZSTD_decompress_usingDict()`) + */ +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), + * 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() : + * 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. + * @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() : + * 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() : + * 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 + *******************************/ + +/*! 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); + +/*! 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. + * Non-conformant dictionaries can still be loaded, but as content-only dictionaries. */ +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); + +/*! 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 piece of 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(), + * ZSTD_compressStream2(), and ZSTD_decompressDCtx(). + * Dictionaries are sticky, they remain valid when same context is reused, + * they only reset when the context is reset + * with ZSTD_reset_parameters or ZSTD_reset_session_and_parameters. + * In contrast, 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, + * until parameters are reset, a new dictionary is loaded, or the dictionary + * is explicitly invalidated by loading a NULL dictionary. + * 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. + * Note 5 : This method does not benefit from LDM (long distance mode). + * If you want to employ LDM on some large dictionary content, + * prefer employing ZSTD_CCtx_refPrefix() described below. + */ +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 future 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); + +/*! 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). + * This method is compatible with LDM (long distance mode). + * @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); + +/*! ZSTD_DCtx_loadDictionary() : Requires v1.4.0+ + * Create an internal DDict from dict buffer, to be used to decompress all future frames. + * The dictionary remains valid for all future frames, until explicitly invalidated, or + * a new dictionary is loaded. + * @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. + * + * 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 + * will be determined at decompression time, as per the dict ID in the frame. + * The memory for the table is allocated on the first call to refDDict, and can be + * freed with ZSTD_freeDCtx(). + * + * If called with ZSTD_d_refMultipleDDicts disabled (the default), only one dictionary + * will be managed, and referencing a dictionary effectively "discards" any previous one. + * + * @result : 0, or an error code (which can be tested with ZSTD_isError()). + * 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. + * 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 === */ + +/*! 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); + +#endif /* ZSTD_H_235446 */ + + +/* ************************************************************************************** + * ADVANCED AND EXPERIMENTAL FUNCTIONS + **************************************************************************************** + * The definitions in the following section are considered experimental. + * They are provided for advanced scenarios. + * They should never be used with a dynamic library, as prototypes may change in the future. + * Use them only in association with static linking. + * ***************************************************************************************/ + +#if defined(ZSTD_STATIC_LINKING_ONLY) && !defined(ZSTD_H_ZSTD_STATIC_LINKING_ONLY) +#define ZSTD_H_ZSTD_STATIC_LINKING_ONLY + +/* This can be overridden externally to hide static symbols. */ +#ifndef ZSTDLIB_STATIC_API +# if defined(ZSTD_DLL_EXPORT) && (ZSTD_DLL_EXPORT==1) +# define ZSTDLIB_STATIC_API __declspec(dllexport) ZSTDLIB_VISIBLE +# elif defined(ZSTD_DLL_IMPORT) && (ZSTD_DLL_IMPORT==1) +# define ZSTDLIB_STATIC_API __declspec(dllimport) ZSTDLIB_VISIBLE +# else +# define ZSTDLIB_STATIC_API ZSTDLIB_VISIBLE +# endif +#endif + +/**************************************************************************************** + * 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_BLOCKSIZE_MAX_MIN (1 << 10) /* The minimum valid max blocksize. Maximum blocksizes smaller than this make compressBound() inaccurate. */ + + +#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< 0: + * If litLength != 0: + * rep == 1 --> offset == repeat_offset_1 + * rep == 2 --> offset == repeat_offset_2 + * rep == 3 --> offset == repeat_offset_3 + * If litLength == 0: + * rep == 1 --> offset == repeat_offset_2 + * rep == 2 --> offset == repeat_offset_3 + * rep == 3 --> offset == repeat_offset_1 - 1 + * + * Note: This field is optional. ZSTD_generateSequences() will calculate the value of + * 'rep', but repeat offsets do not necessarily need to be calculated from an external + * sequence provider's perspective. For example, ZSTD_compressSequences() does not + * use this 'rep' field at all (as of now). + */ +} 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 */ +} 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) */ +} ZSTD_frameParameters; + +typedef struct { + ZSTD_compressionParameters cParams; + ZSTD_frameParameters fParams; +} 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_dictContentType_e; + +typedef enum { + 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) */ + 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; + +typedef enum { + /* Note: this enum controls ZSTD_d_forceIgnoreChecksum */ + ZSTD_d_validateChecksum = 0, + ZSTD_d_ignoreChecksum = 1 +} ZSTD_forceIgnoreChecksum_e; + +typedef enum { + /* Note: this enum controls ZSTD_d_refMultipleDDicts */ + ZSTD_rmd_refSingleDDict = 0, + ZSTD_rmd_refMultipleDDicts = 1 +} 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. + * + * 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 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_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_lcm_uncompressed = 2 /**< Always emit uncompressed literals. */ +} 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 + * or ZSTD_ps_disable allow for a force enable/disable the feature. + */ + ZSTD_ps_auto = 0, /* Let the library automatically determine whether the feature shall be enabled */ + ZSTD_ps_enable = 1, /* Force-enable the feature */ + ZSTD_ps_disable = 2 /* Do not use the feature */ +} ZSTD_paramSwitch_e; + +/*************************************** +* Frame header and size functions +***************************************/ + +/*! ZSTD_findDecompressedSize() : + * `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 : - 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 + * + * note 1 : decompressed size is an optional field, that may not be present, especially in streaming mode. + * When `return==ZSTD_CONTENTSIZE_UNKNOWN`, data to decompress could be any size. + * In which case, it's necessary to use streaming mode to decompress data. + * note 2 : decompressed size is always present when compression is done with ZSTD_compress() + * note 3 : 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. + * note 4 : If source is untrusted, decompressed size could be wrong or intentionally modified. + * Always ensure result fits within application's authorized limits. + * Each application can set its own limits. + * note 5 : ZSTD_findDecompressedSize handles multiple frames, and so it must traverse the input to + * read each contained frame header. This is fast as most of the data is skipped, + * however it does mean that all frame data must be present and valid. */ +ZSTDLIB_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 + * - 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) + */ +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) */ +ZSTDLIB_STATIC_API size_t ZSTD_frameHeaderSize(const void* src, size_t srcSize); + +typedef enum { ZSTD_frame, ZSTD_skippableFrame } ZSTD_frameType_e; +typedef struct { + unsigned long long frameContentSize; /* if == ZSTD_CONTENTSIZE_UNKNOWN, it means this field is not available. 0 means "empty" */ + unsigned long long windowSize; /* can be very large, up to <= frameContentSize */ + unsigned blockSizeMax; + ZSTD_frameType_e frameType; /* if == ZSTD_skippableFrame, frameContentSize is the size of skippable content */ + unsigned headerSize; + unsigned dictID; + unsigned checksumFlag; + unsigned _reserved1; + unsigned _reserved2; +} 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() */ +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) */ +ZSTDLIB_STATIC_API size_t ZSTD_getFrameHeader_advanced(ZSTD_frameHeader* zfhPtr, const void* src, size_t srcSize, ZSTD_format_e format); + +/*! ZSTD_decompressionMargin() : + * Zstd supports in-place decompression, where the input and output buffers overlap. + * In this case, the output buffer must be at least (Margin + Output_Size) bytes large, + * and the input buffer must be at the end of the output buffer. + * + * _______________________ Output Buffer ________________________ + * | | + * | ____ Input Buffer ____| + * | | | + * v v v + * |---------------------------------------|-----------|----------| + * ^ ^ ^ + * |___________________ Output_Size ___________________|_ Margin _| + * + * NOTE: See also ZSTD_DECOMPRESSION_MARGIN(). + * NOTE: This applies only to single-pass decompression through ZSTD_decompress() or + * ZSTD_decompressDCtx(). + * NOTE: This function supports multi-frame input. + * + * @param src The compressed frame(s) + * @param srcSize The size of the compressed frame(s) + * @returns The decompression margin or an error that can be checked with ZSTD_isError(). + */ +ZSTDLIB_STATIC_API size_t ZSTD_decompressionMargin(const void* src, size_t srcSize); + +/*! ZSTD_DECOMPRESS_MARGIN() : + * Similar to ZSTD_decompressionMargin(), but instead of computing the margin from + * the compressed frame, compute it from the original size and the blockSizeLog. + * See ZSTD_decompressionMargin() for details. + * + * WARNING: This macro does not support multi-frame input, the input must be a single + * zstd frame. If you need that support use the function, or implement it yourself. + * + * @param originalSize The original uncompressed size of the data. + * @param blockSize The block size == MIN(windowSize, ZSTD_BLOCKSIZE_MAX). + * Unless you explicitly set the windowLog smaller than + * ZSTD_BLOCKSIZELOG_MAX you can just use ZSTD_BLOCKSIZE_MAX. + */ +#define ZSTD_DECOMPRESSION_MARGIN(originalSize, blockSize) ((size_t)( \ + ZSTD_FRAMEHEADERSIZE_MAX /* Frame header */ + \ + 4 /* checksum */ + \ + ((originalSize) == 0 ? 0 : 3 * (((originalSize) + (blockSize) - 1) / blockSize)) /* 3 bytes per block */ + \ + (blockSize) /* One block of margin */ \ + )) + +typedef enum { + ZSTD_sf_noBlockDelimiters = 0, /* Representation of ZSTD_Sequence has no block delimiters, sequences only */ + ZSTD_sf_explicitBlockDelimiters = 1 /* Representation of ZSTD_Sequence contains explicit block delimiters */ +} ZSTD_sequenceFormat_e; + +/*! ZSTD_sequenceBound() : + * `srcSize` : size of the input buffer + * @return : upper-bound for the number of sequences that can be generated + * from a buffer of srcSize bytes + * + * note : returns number of sequences - to get bytes, multiply by sizeof(ZSTD_Sequence). + */ +ZSTDLIB_STATIC_API size_t ZSTD_sequenceBound(size_t srcSize); + +/*! ZSTD_generateSequences() : + * WARNING: This function is meant for debugging and informational purposes ONLY! + * Its implementation is flawed, and it will be deleted in a future version. + * It is not guaranteed to succeed, as there are several cases where it will give + * up and fail. You should NOT use this function in production code. + * + * This function is deprecated, and will be removed in a future version. + * + * Generate sequences using ZSTD_compress2(), given a source buffer. + * + * @param zc The compression context to be used for ZSTD_compress2(). Set any + * compression parameters you need on this context. + * @param outSeqs The output sequences buffer of size @p outSeqsSize + * @param outSeqsSize The size of the output sequences buffer. + * ZSTD_sequenceBound(srcSize) is an upper bound on the number + * of sequences that can be generated. + * @param src The source buffer to generate sequences from of size @p srcSize. + * @param srcSize The size of the source buffer. + * + * Each block will end with a dummy sequence + * with offset == 0, matchLength == 0, and litLength == length of last literals. + * litLength may be == 0, and if so, then the sequence of (of: 0 ml: 0 ll: 0) + * simply acts as a block delimiter. + * + * @returns The number of sequences generated, necessarily less than + * ZSTD_sequenceBound(srcSize), or an error code that can be checked + * with ZSTD_isError(). + */ +ZSTD_DEPRECATED("For debugging only, will be replaced by ZSTD_extractSequences()") +ZSTDLIB_STATIC_API size_t +ZSTD_generateSequences(ZSTD_CCtx* zc, + ZSTD_Sequence* outSeqs, size_t outSeqsSize, + const void* src, size_t srcSize); + +/*! ZSTD_mergeBlockDelimiters() : + * Given an array of ZSTD_Sequence, remove all sequences that represent block delimiters/last literals + * by merging them into the literals of the next sequence. + * + * As such, the final generated result has no explicit representation of block boundaries, + * and the final last literals segment is not represented in the sequences. + * + * The output of this function can be fed into ZSTD_compressSequences() with CCtx + * setting of ZSTD_c_blockDelimiters as ZSTD_sf_noBlockDelimiters + * @return : number of sequences left after merging + */ +ZSTDLIB_STATIC_API size_t ZSTD_mergeBlockDelimiters(ZSTD_Sequence* sequences, size_t seqsSize); + +/*! ZSTD_compressSequences() : + * Compress an array of ZSTD_Sequence, associated with @src buffer, into dst. + * @src contains the entire input (not just the literals). + * If @srcSize > sum(sequence.length), the remaining bytes are considered all literals + * If a dictionary is included, then the cctx should reference the dict. (see: ZSTD_CCtx_refCDict(), ZSTD_CCtx_loadDictionary(), etc.) + * The entire source is compressed into a single frame. + * + * The compression behavior changes based on cctx params. In particular: + * If ZSTD_c_blockDelimiters == ZSTD_sf_noBlockDelimiters, the array of ZSTD_Sequence is expected to contain + * no block delimiters (defined in ZSTD_Sequence). Block boundaries are roughly determined based on + * the block size derived from the cctx, and sequences may be split. This is the default setting. + * + * If ZSTD_c_blockDelimiters == ZSTD_sf_explicitBlockDelimiters, the array of ZSTD_Sequence is expected to contain + * block delimiters (defined in ZSTD_Sequence). Behavior is undefined if no block delimiters are provided. + * + * If ZSTD_c_validateSequences == 0, this function will blindly accept the sequences provided. Invalid sequences cause undefined + * behavior. If ZSTD_c_validateSequences == 1, then if sequence is invalid (see doc/zstd_compression_format.md for + * specifics regarding offset/matchlength requirements) then the function will bail out and return an error. + * + * In addition to the two adjustable experimental params, there are other important cctx params. + * - ZSTD_c_minMatch MUST be set as less than or equal to the smallest match generated by the match finder. It has a minimum value of ZSTD_MINMATCH_MIN. + * - ZSTD_c_compressionLevel accordingly adjusts the strength of the entropy coder, as it would in typical compression. + * - ZSTD_c_windowLog affects offset validation: this function will return an error at higher debug levels if a provided offset + * is larger than what the spec allows for a given window log and dictionary (if present). See: doc/zstd_compression_format.md + * + * Note: Repcodes are, as of now, always re-calculated within this function, so ZSTD_Sequence::rep is unused. + * Note 2: Once we integrate ability to ingest repcodes, the explicit block delims mode must respect those repcodes exactly, + * and cannot emit an RLE block that disagrees with the repcode history + * @return : final compressed size, or a ZSTD error code. + */ +ZSTDLIB_STATIC_API size_t +ZSTD_compressSequences( ZSTD_CCtx* cctx, void* dst, size_t dstSize, + const ZSTD_Sequence* inSeqs, size_t inSeqsSize, + const void* src, size_t srcSize); + + +/*! ZSTD_writeSkippableFrame() : + * Generates a zstd skippable frame containing data given by src, and writes it to dst buffer. + * + * Skippable frames begin with a 4-byte magic number. There are 16 possible choices of magic number, + * ranging from ZSTD_MAGIC_SKIPPABLE_START to ZSTD_MAGIC_SKIPPABLE_START+15. + * As such, the parameter magicVariant controls the exact skippable frame magic number variant used, so + * the magic number used will be ZSTD_MAGIC_SKIPPABLE_START + magicVariant. + * + * Returns an error if destination buffer is not large enough, if the source size is not representable + * with a 4-byte unsigned int, or if the parameter magicVariant is greater than 15 (and therefore invalid). + * + * @return : number of bytes written or a ZSTD error. + */ +ZSTDLIB_STATIC_API size_t ZSTD_writeSkippableFrame(void* dst, size_t dstCapacity, + const void* src, size_t srcSize, unsigned magicVariant); + +/*! ZSTD_readSkippableFrame() : + * Retrieves a zstd skippable frame containing data given by src, and writes it to dst buffer. + * + * The parameter magicVariant will receive the magicVariant that was supplied when the frame was written, + * i.e. magicNumber - ZSTD_MAGIC_SKIPPABLE_START. This can be NULL if the caller is not interested + * in the magicVariant. + * + * Returns an error if destination buffer is not large enough, or if the frame is not skippable. + * + * @return : number of bytes written or a ZSTD error. + */ +ZSTDLIB_API size_t ZSTD_readSkippableFrame(void* dst, size_t dstCapacity, unsigned* magicVariant, + const void* src, size_t srcSize); + +/*! ZSTD_isSkippableFrame() : + * Tells if the content of `buffer` starts with a valid Frame Identifier for a skippable frame. + */ +ZSTDLIB_API unsigned ZSTD_isSkippableFrame(const void* buffer, size_t size); + + + +/*************************************** +* Memory management +***************************************/ + +/*! ZSTD_estimate*() : + * These functions make it possible to estimate memory usage + * of a future {D,C}Ctx, before its creation. + * This is useful in combination with ZSTD_initStatic(), + * which makes it possible to employ a static buffer for ZSTD_CCtx* state. + * + * ZSTD_estimateCCtxSize() will provide a memory budget large enough + * to compress data of any size using one-shot compression ZSTD_compressCCtx() or ZSTD_compress2() + * associated with any compression level up to max specified one. + * The estimate will assume the input may be arbitrarily large, + * which is the worst case. + * + * Note that the size estimation is specific for one-shot compression, + * it is not valid for streaming (see ZSTD_estimateCStreamSize*()) + * nor other potential ways of using a ZSTD_CCtx* state. + * + * When srcSize can be bound by a known and rather "small" value, + * this knowledge can be used to provide a tighter budget estimation + * because the ZSTD_CCtx* state will need less memory for small inputs. + * This tighter estimation can be provided by employing more advanced functions + * ZSTD_estimateCCtxSize_usingCParams(), which can be used in tandem with ZSTD_getCParams(), + * and ZSTD_estimateCCtxSize_usingCCtxParams(), which can be used in tandem with ZSTD_CCtxParams_setParameter(). + * Both can be used to estimate memory using custom compression parameters and arbitrary srcSize limits. + * + * Note : only single-threaded compression is supported. + * ZSTD_estimateCCtxSize_usingCCtxParams() will return an error code if ZSTD_c_nbWorkers is >= 1. + */ +ZSTDLIB_STATIC_API size_t ZSTD_estimateCCtxSize(int maxCompressionLevel); +ZSTDLIB_STATIC_API size_t ZSTD_estimateCCtxSize_usingCParams(ZSTD_compressionParameters cParams); +ZSTDLIB_STATIC_API size_t ZSTD_estimateCCtxSize_usingCCtxParams(const ZSTD_CCtx_params* params); +ZSTDLIB_STATIC_API size_t ZSTD_estimateDCtxSize(void); + +/*! ZSTD_estimateCStreamSize() : + * ZSTD_estimateCStreamSize() will provide a memory budget large enough for streaming compression + * using any compression level up to the max specified one. + * It will also consider src size to be arbitrarily "large", which is a worst case scenario. + * 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. + * Note : CStream size estimation is only correct for single-threaded compression. + * ZSTD_estimateCStreamSize_usingCCtxParams() will return an error code if ZSTD_c_nbWorkers is >= 1. + * Note 2 : ZSTD_estimateCStreamSize* functions are not compatible with the Block-Level Sequence Producer API at this time. + * Size estimates assume that no external sequence producer is registered. + * + * ZSTD_DStream memory budget depends on frame's window Size. + * This information can be passed manually, using ZSTD_estimateDStreamSize, + * or deducted from a valid frame Header, using ZSTD_estimateDStreamSize_fromFrame(); + * Any frame requesting a window size larger than max specified one will be rejected. + * Note : if streaming is init with function ZSTD_init?Stream_usingDict(), + * an internal ?Dict will be created, which additional size is not estimated here. + * In this case, get total size by adding ZSTD_estimate?DictSize + */ +ZSTDLIB_STATIC_API size_t ZSTD_estimateCStreamSize(int maxCompressionLevel); +ZSTDLIB_STATIC_API size_t ZSTD_estimateCStreamSize_usingCParams(ZSTD_compressionParameters cParams); +ZSTDLIB_STATIC_API size_t ZSTD_estimateCStreamSize_usingCCtxParams(const ZSTD_CCtx_params* params); +ZSTDLIB_STATIC_API size_t ZSTD_estimateDStreamSize(size_t maxWindowSize); +ZSTDLIB_STATIC_API size_t ZSTD_estimateDStreamSize_fromFrame(const void* src, size_t srcSize); + +/*! ZSTD_estimate?DictSize() : + * ZSTD_estimateCDictSize() will bet that src size is relatively "small", and content is copied, like ZSTD_createCDict(). + * ZSTD_estimateCDictSize_advanced() makes it possible to control compression parameters precisely, like ZSTD_createCDict_advanced(). + * Note : dictionaries created by reference (`ZSTD_dlm_byRef`) are logically smaller. + */ +ZSTDLIB_STATIC_API size_t ZSTD_estimateCDictSize(size_t dictSize, int compressionLevel); +ZSTDLIB_STATIC_API size_t ZSTD_estimateCDictSize_advanced(size_t dictSize, ZSTD_compressionParameters cParams, ZSTD_dictLoadMethod_e dictLoadMethod); +ZSTDLIB_STATIC_API size_t ZSTD_estimateDDictSize(size_t dictSize, ZSTD_dictLoadMethod_e dictLoadMethod); + +/*! ZSTD_initStatic*() : + * Initialize an object using a pre-allocated fixed-size buffer. + * workspace: The memory area to emplace the object into. + * Provided pointer *must be 8-bytes aligned*. + * Buffer must outlive object. + * workspaceSize: Use ZSTD_estimate*Size() to determine + * how large workspace must be to support target scenario. + * @return : pointer to object (same address as workspace, just different type), + * or NULL if error (size too small, incorrect alignment, etc.) + * Note : zstd will never resize nor malloc() when using a static buffer. + * If the object requires more memory than available, + * zstd will just error out (typically ZSTD_error_memory_allocation). + * Note 2 : there is no corresponding "free" function. + * Since workspace is allocated externally, it must be freed externally too. + * Note 3 : cParams : use ZSTD_getCParams() to convert a compression level + * into its associated cParams. + * Limitation 1 : currently not compatible with internal dictionary creation, triggered by + * ZSTD_CCtx_loadDictionary(), ZSTD_initCStream_usingDict() or ZSTD_initDStream_usingDict(). + * Limitation 2 : static cctx currently not compatible with multi-threading. + * Limitation 3 : static dctx is incompatible with legacy support. + */ +ZSTDLIB_STATIC_API ZSTD_CCtx* ZSTD_initStaticCCtx(void* workspace, size_t workspaceSize); +ZSTDLIB_STATIC_API ZSTD_CStream* ZSTD_initStaticCStream(void* workspace, size_t workspaceSize); /**< same as ZSTD_initStaticCCtx() */ + +ZSTDLIB_STATIC_API ZSTD_DCtx* ZSTD_initStaticDCtx(void* workspace, size_t workspaceSize); +ZSTDLIB_STATIC_API ZSTD_DStream* ZSTD_initStaticDStream(void* workspace, size_t workspaceSize); /**< same as ZSTD_initStaticDCtx() */ + +ZSTDLIB_STATIC_API const ZSTD_CDict* ZSTD_initStaticCDict( + void* workspace, size_t workspaceSize, + const void* dict, size_t dictSize, + ZSTD_dictLoadMethod_e dictLoadMethod, + ZSTD_dictContentType_e dictContentType, + ZSTD_compressionParameters cParams); + +ZSTDLIB_STATIC_API const ZSTD_DDict* ZSTD_initStaticDDict( + void* workspace, size_t workspaceSize, + const void* dict, size_t dictSize, + 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. + * All allocation/free operations will be completed using these custom variants instead of regular ones. + */ +typedef void* (*ZSTD_allocFunction) (void* opaque, size_t size); +typedef void (*ZSTD_freeFunction) (void* opaque, void* address); +typedef struct { ZSTD_allocFunction customAlloc; ZSTD_freeFunction customFree; void* opaque; } ZSTD_customMem; +static +#ifdef __GNUC__ +__attribute__((__unused__)) +#endif +ZSTD_customMem const ZSTD_defaultCMem = { NULL, NULL, NULL }; /**< this constant defers to stdlib's functions */ + +ZSTDLIB_STATIC_API ZSTD_CCtx* ZSTD_createCCtx_advanced(ZSTD_customMem customMem); +ZSTDLIB_STATIC_API ZSTD_CStream* ZSTD_createCStream_advanced(ZSTD_customMem customMem); +ZSTDLIB_STATIC_API ZSTD_DCtx* ZSTD_createDCtx_advanced(ZSTD_customMem customMem); +ZSTDLIB_STATIC_API ZSTD_DStream* ZSTD_createDStream_advanced(ZSTD_customMem customMem); + +ZSTDLIB_STATIC_API ZSTD_CDict* ZSTD_createCDict_advanced(const void* dict, size_t dictSize, + ZSTD_dictLoadMethod_e dictLoadMethod, + ZSTD_dictContentType_e dictContentType, + ZSTD_compressionParameters cParams, + ZSTD_customMem customMem); + +/*! Thread pool : + * These prototypes make it possible to share a thread pool among multiple compression contexts. + * This can limit resources for applications with multiple threads where each one uses + * a threaded compression mode (via ZSTD_c_nbWorkers parameter). + * ZSTD_createThreadPool creates a new thread pool with a given number of threads. + * Note that the lifetime of such pool must exist while being used. + * ZSTD_CCtx_refThreadPool assigns a thread pool to a context (use NULL argument value + * to use an internal thread pool). + * ZSTD_freeThreadPool frees a thread pool, accepts NULL pointer. + */ +typedef struct POOL_ctx_s ZSTD_threadPool; +ZSTDLIB_STATIC_API ZSTD_threadPool* ZSTD_createThreadPool(size_t numThreads); +ZSTDLIB_STATIC_API void ZSTD_freeThreadPool (ZSTD_threadPool* pool); /* accept NULL pointer */ +ZSTDLIB_STATIC_API size_t ZSTD_CCtx_refThreadPool(ZSTD_CCtx* cctx, ZSTD_threadPool* pool); + + +/* + * This API is temporary and is expected to change or disappear in the future! + */ +ZSTDLIB_STATIC_API ZSTD_CDict* ZSTD_createCDict_advanced2( + const void* dict, size_t dictSize, + ZSTD_dictLoadMethod_e dictLoadMethod, + ZSTD_dictContentType_e dictContentType, + const ZSTD_CCtx_params* cctxParams, + ZSTD_customMem customMem); + +ZSTDLIB_STATIC_API ZSTD_DDict* ZSTD_createDDict_advanced( + const void* dict, size_t dictSize, + ZSTD_dictLoadMethod_e dictLoadMethod, + ZSTD_dictContentType_e dictContentType, + ZSTD_customMem customMem); + + +/*************************************** +* Advanced compression functions +***************************************/ + +/*! ZSTD_createCDict_byReference() : + * Create a digested dictionary for compression + * 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 */ +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 */ +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()) */ +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) */ +ZSTDLIB_STATIC_API ZSTD_compressionParameters ZSTD_adjustCParams(ZSTD_compressionParameters cPar, unsigned long long srcSize, size_t dictSize); + +/*! ZSTD_CCtx_setCParams() : + * Set all parameters provided within @p cparams into the working @p cctx. + * Note : if modifying parameters during compression (MT mode only), + * note that changes to the .windowLog parameter will be ignored. + * @return 0 on success, or an error code (can be checked with ZSTD_isError()). + * On failure, no parameters are updated. + */ +ZSTDLIB_STATIC_API size_t ZSTD_CCtx_setCParams(ZSTD_CCtx* cctx, ZSTD_compressionParameters cparams); + +/*! ZSTD_CCtx_setFParams() : + * Set all parameters provided within @p fparams into the working @p cctx. + * @return 0 on success, or an error code (can be checked with ZSTD_isError()). + */ +ZSTDLIB_STATIC_API size_t ZSTD_CCtx_setFParams(ZSTD_CCtx* cctx, ZSTD_frameParameters fparams); + +/*! ZSTD_CCtx_setParams() : + * Set all parameters provided within @p params into the working @p cctx. + * @return 0 on success, or an error code (can be checked with ZSTD_isError()). + */ +ZSTDLIB_STATIC_API size_t ZSTD_CCtx_setParams(ZSTD_CCtx* cctx, ZSTD_parameters params); + +/*! ZSTD_compress_advanced() : + * Note : this function is now DEPRECATED. + * It can be replaced by ZSTD_compress2(), in combination with ZSTD_CCtx_setParameter() and other parameter setters. + * This prototype will generate compilation warnings. */ +ZSTD_DEPRECATED("use ZSTD_compress2") +ZSTDLIB_STATIC_API +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); + +/*! ZSTD_compress_usingCDict_advanced() : + * Note : this function is now DEPRECATED. + * It can be replaced by ZSTD_compress2(), in combination with ZSTD_CCtx_loadDictionary() and other parameter setters. + * This prototype will generate compilation warnings. */ +ZSTD_DEPRECATED("use ZSTD_compress2 with ZSTD_CCtx_loadDictionary") +ZSTDLIB_STATIC_API +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); + + +/*! 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 ?) */ +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 ?) */ +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 + +/* Controlled with ZSTD_paramSwitch_e enum. + * Default is ZSTD_ps_auto. + * Set to ZSTD_ps_disable to never compress literals. + * Set to ZSTD_ps_enable to always compress literals. (Note: uncompressed literals + * may still be emitted if huffman is not beneficial to use.) + * + * 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 + +/* User's best guess of source size. + * Hint is not valid when srcSizeHint == 0. + * There is no guarantee that hint is close to actual source size, + * but compression ratio may regress significantly if guess considerably underestimates */ +#define ZSTD_c_srcSizeHint ZSTD_c_experimentalParam7 + +/* Controls whether the new and experimental "dedicated dictionary search + * structure" can be used. This feature is still rough around the edges, be + * prepared for surprising behavior! + * + * How to use it: + * + * When using a CDict, whether to use this feature or not is controlled at + * CDict creation, and it must be set in a CCtxParams set passed into that + * construction (via ZSTD_createCDict_advanced2()). A compression will then + * use the feature or not based on how the CDict was constructed; the value of + * this param, set in the CCtx, will have no effect. + * + * However, when a dictionary buffer is passed into a CCtx, such as via + * ZSTD_CCtx_loadDictionary(), this param can be set on the CCtx to control + * whether the CDict that is created internally can use the feature or not. + * + * What it does: + * + * Normally, the internal data structures of the CDict are analogous to what + * would be stored in a CCtx after compressing the contents of a dictionary. + * To an approximation, a compression using a dictionary can then use those + * data structures to simply continue what is effectively a streaming + * compression where the simulated compression of the dictionary left off. + * Which is to say, the search structures in the CDict are normally the same + * format as in the CCtx. + * + * It is possible to do better, since the CDict is not like a CCtx: the search + * structures are written once during CDict creation, and then are only read + * after that, while the search structures in the CCtx are both read and + * written as the compression goes along. This means we can choose a search + * structure for the dictionary that is read-optimized. + * + * This feature enables the use of that different structure. + * + * Note that some of the members of the ZSTD_compressionParameters struct have + * different semantics and constraints in the dedicated search structure. It is + * highly recommended that you simply set a compression level in the CCtxParams + * you pass into the CDict creation call, and avoid messing with the cParams + * directly. + * + * Effects: + * + * This will only have any effect when the selected ZSTD_strategy + * implementation supports this feature. Currently, that's limited to + * ZSTD_greedy, ZSTD_lazy, and ZSTD_lazy2. + * + * Note that this means that the CDict tables can no longer be copied into the + * CCtx, so the dict attachment mode ZSTD_dictForceCopy will no longer be + * usable. The dictionary can only be attached or reloaded. + * + * In general, you should expect compression to be faster--sometimes very much + * so--and CDict creation to be slightly slower. Eventually, we will probably + * make this mode the default. + */ +#define ZSTD_c_enableDedicatedDictSearch ZSTD_c_experimentalParam8 + +/* ZSTD_c_stableInBuffer + * Experimental parameter. + * Default is 0 == disabled. Set to 1 to enable. + * + * Tells the compressor that input data presented with ZSTD_inBuffer + * will ALWAYS be the same between calls. + * Technically, the @src pointer must never be changed, + * and the @pos field can only be updated by zstd. + * However, it's possible to increase the @size field, + * allowing scenarios where more data can be appended after compressions starts. + * These conditions are checked by the compressor, + * and compression will fail if they are not respected. + * Also, data in the ZSTD_inBuffer within the range [src, src + pos) + * MUST not be modified during compression or it will result in data corruption. + * + * When this flag is enabled zstd won't allocate an input window buffer, + * because the user guarantees it can reference the ZSTD_inBuffer until + * the frame is complete. But, it will still allocate an output buffer + * large enough to fit a block (see ZSTD_c_stableOutBuffer). This will also + * avoid the memcpy() from the input buffer to the input window buffer. + * + * NOTE: So long as the ZSTD_inBuffer always points to valid memory, using + * this flag is ALWAYS memory safe, and will never access out-of-bounds + * memory. However, compression WILL fail if conditions are not respected. + * + * WARNING: The data in the ZSTD_inBuffer in the range [src, src + pos) MUST + * not be modified during compression or it will result in data corruption. + * This is because zstd needs to reference data in the ZSTD_inBuffer to find + * matches. Normally zstd maintains its own window buffer for this purpose, + * but passing this flag tells zstd to rely on user provided buffer instead. + */ +#define ZSTD_c_stableInBuffer ZSTD_c_experimentalParam9 + +/* ZSTD_c_stableOutBuffer + * Experimental parameter. + * Default is 0 == disabled. Set to 1 to enable. + * + * Tells he compressor that the ZSTD_outBuffer will not be resized between + * calls. Specifically: (out.size - out.pos) will never grow. This gives the + * compressor the freedom to say: If the compressed data doesn't fit in the + * output buffer then return ZSTD_error_dstSizeTooSmall. This allows us to + * always decompress directly into the output buffer, instead of decompressing + * into an internal buffer and copying to the output buffer. + * + * When this flag is enabled zstd won't allocate an output buffer, because + * it can write directly to the ZSTD_outBuffer. It will still allocate the + * input window buffer (see ZSTD_c_stableInBuffer). + * + * Zstd will check that (out.size - out.pos) never grows and return an error + * if it does. While not strictly necessary, this should prevent surprises. + */ +#define ZSTD_c_stableOutBuffer ZSTD_c_experimentalParam10 + +/* ZSTD_c_blockDelimiters + * Default is 0 == ZSTD_sf_noBlockDelimiters. + * + * For use with sequence compression API: ZSTD_compressSequences(). + * + * Designates whether or not the given array of ZSTD_Sequence contains block delimiters + * and last literals, which are defined as sequences with offset == 0 and matchLength == 0. + * See the definition of ZSTD_Sequence for more specifics. + */ +#define ZSTD_c_blockDelimiters ZSTD_c_experimentalParam11 + +/* ZSTD_c_validateSequences + * Default is 0 == disabled. Set to 1 to enable sequence validation. + * + * For use with sequence compression API: ZSTD_compressSequences(). + * Designates whether or not we validate sequences provided to ZSTD_compressSequences() + * during function execution. + * + * Without validation, providing a sequence that does not conform to the zstd spec will cause + * undefined behavior, and may produce a corrupted block. + * + * With validation enabled, if sequence is invalid (see doc/zstd_compression_format.md for + * specifics regarding offset/matchlength requirements) then the function will bail out and + * return an error. + * + */ +#define ZSTD_c_validateSequences ZSTD_c_experimentalParam12 + +/* ZSTD_c_useBlockSplitter + * Controlled with ZSTD_paramSwitch_e enum. + * Default is ZSTD_ps_auto. + * Set to ZSTD_ps_disable to never use block splitter. + * Set to ZSTD_ps_enable to always use block splitter. + * + * By default, in ZSTD_ps_auto, the library will decide at runtime whether to use + * block splitting based on the compression parameters. + */ +#define ZSTD_c_useBlockSplitter ZSTD_c_experimentalParam13 + +/* ZSTD_c_useRowMatchFinder + * Controlled with ZSTD_paramSwitch_e enum. + * Default is ZSTD_ps_auto. + * Set to ZSTD_ps_disable to never use row-based matchfinder. + * Set to ZSTD_ps_enable to force usage of row-based matchfinder. + * + * By default, in ZSTD_ps_auto, the library will decide at runtime whether to use + * the row-based matchfinder based on support for SIMD instructions and the window log. + * Note that this only pertains to compression strategies: greedy, lazy, and lazy2 + */ +#define ZSTD_c_useRowMatchFinder ZSTD_c_experimentalParam14 + +/* ZSTD_c_deterministicRefPrefix + * Default is 0 == disabled. Set to 1 to enable. + * + * Zstd produces different results for prefix compression when the prefix is + * directly adjacent to the data about to be compressed vs. when it isn't. + * This is because zstd detects that the two buffers are contiguous and it can + * use a more efficient match finding algorithm. However, this produces different + * results than when the two buffers are non-contiguous. This flag forces zstd + * to always load the prefix in non-contiguous mode, even if it happens to be + * adjacent to the data, to guarantee determinism. + * + * If you really care about determinism when using a dictionary or prefix, + * like when doing delta compression, you should select this option. It comes + * at a speed penalty of about ~2.5% if the dictionary and data happened to be + * contiguous, and is free if they weren't contiguous. We don't expect that + * intentionally making the dictionary and data contiguous will be worth the + * cost to memcpy() the data. + */ +#define ZSTD_c_deterministicRefPrefix ZSTD_c_experimentalParam15 + +/* ZSTD_c_prefetchCDictTables + * Controlled with ZSTD_paramSwitch_e enum. Default is ZSTD_ps_auto. + * + * In some situations, zstd uses CDict tables in-place rather than copying them + * into the working context. (See docs on ZSTD_dictAttachPref_e above for details). + * In such situations, compression speed is seriously impacted when CDict tables are + * "cold" (outside CPU cache). This parameter instructs zstd to prefetch CDict tables + * when they are used in-place. + * + * For sufficiently small inputs, the cost of the prefetch will outweigh the benefit. + * For sufficiently large inputs, zstd will by default memcpy() CDict tables + * into the working context, so there is no need to prefetch. This parameter is + * targeted at a middle range of input sizes, where a prefetch is cheap enough to be + * useful but memcpy() is too expensive. The exact range of input sizes where this + * makes sense is best determined by careful experimentation. + * + * Note: for this parameter, ZSTD_ps_auto is currently equivalent to ZSTD_ps_disable, + * but in the future zstd may conditionally enable this feature via an auto-detection + * heuristic for cold CDicts. + * Use ZSTD_ps_disable to opt out of prefetching under any circumstances. + */ +#define ZSTD_c_prefetchCDictTables ZSTD_c_experimentalParam16 + +/* ZSTD_c_enableSeqProducerFallback + * Allowed values are 0 (disable) and 1 (enable). The default setting is 0. + * + * Controls whether zstd will fall back to an internal sequence producer if an + * external sequence producer is registered and returns an error code. This fallback + * is block-by-block: the internal sequence producer will only be called for blocks + * where the external sequence producer returns an error code. Fallback parsing will + * follow any other cParam settings, such as compression level, the same as in a + * normal (fully-internal) compression operation. + * + * The user is strongly encouraged to read the full Block-Level Sequence Producer API + * documentation (below) before setting this parameter. */ +#define ZSTD_c_enableSeqProducerFallback ZSTD_c_experimentalParam17 + +/* ZSTD_c_maxBlockSize + * Allowed values are between 1KB and ZSTD_BLOCKSIZE_MAX (128KB). + * The default is ZSTD_BLOCKSIZE_MAX, and setting to 0 will set to the default. + * + * This parameter can be used to set an upper bound on the blocksize + * that overrides the default ZSTD_BLOCKSIZE_MAX. It cannot be used to set upper + * bounds greater than ZSTD_BLOCKSIZE_MAX or bounds lower than 1KB (will make + * compressBound() inaccurate). Only currently meant to be used for testing. + * + */ +#define ZSTD_c_maxBlockSize ZSTD_c_experimentalParam18 + +/* ZSTD_c_searchForExternalRepcodes + * This parameter affects how zstd parses external sequences, such as sequences + * provided through the compressSequences() API or from an external block-level + * sequence producer. + * + * If set to ZSTD_ps_enable, the library will check for repeated offsets in + * external sequences, even if those repcodes are not explicitly indicated in + * the "rep" field. Note that this is the only way to exploit repcode matches + * while using compressSequences() or an external sequence producer, since zstd + * currently ignores the "rep" field of external sequences. + * + * If set to ZSTD_ps_disable, the library will not exploit repeated offsets in + * external sequences, regardless of whether the "rep" field has been set. This + * reduces sequence compression overhead by about 25% while sacrificing some + * compression ratio. + * + * The default value is ZSTD_ps_auto, for which the library will enable/disable + * based on compression level. + * + * Note: for now, this param only has an effect if ZSTD_c_blockDelimiters is + * set to ZSTD_sf_explicitBlockDelimiters. That may change in the future. + */ +#define ZSTD_c_searchForExternalRepcodes ZSTD_c_experimentalParam19 + +/*! 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_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. + */ +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. + */ +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. + */ +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. + */ +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. + * 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()). + */ +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). + */ +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. + */ +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_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. + * Note 2 : Legacy Frame Identifiers are considered valid only if Legacy Support is enabled. + * Note 3 : Skippable Frame Identifiers are considered valid. */ +ZSTDLIB_STATIC_API unsigned ZSTD_isFrame(const void* buffer, size_t size); + +/*! ZSTD_createDDict_byReference() : + * Create a digested dictionary, ready to start decompression operation without startup delay. + * Dictionary content is referenced, and therefore stays in dictBuffer. + * It is important that dictBuffer outlives DDict, + * 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. */ +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 ?). */ +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 ?) */ +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()). + */ +ZSTDLIB_STATIC_API size_t ZSTD_DCtx_setMaxWindowSize(ZSTD_DCtx* dctx, size_t maxWindowSize); + +/*! ZSTD_DCtx_getParameter() : + * Get the requested decompression parameter value, selected by enum ZSTD_dParameter, + * 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_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_stableOutBuffer + * Experimental parameter. + * Default is 0 == disabled. Set to 1 to enable. + * + * Tells the decompressor that the ZSTD_outBuffer will ALWAYS be the same + * between calls, except for the modifications that zstd makes to pos (the + * caller must not modify pos). This is checked by the decompressor, and + * decompression will fail if it ever changes. Therefore the ZSTD_outBuffer + * MUST be large enough to fit the entire decompressed frame. This will be + * checked when the frame content size is known. The data in the ZSTD_outBuffer + * in the range [dst, dst + pos) MUST not be modified during decompression + * or you will get data corruption. + * + * When this flag is enabled zstd won't allocate an output buffer, because + * it can write directly to the ZSTD_outBuffer, but it will still allocate + * an input buffer large enough to fit any compressed block. This will also + * avoid the memcpy() from the internal output buffer to the ZSTD_outBuffer. + * If you need to avoid the input buffer allocation use the buffer-less + * streaming API. + * + * NOTE: So long as the ZSTD_outBuffer always points to valid memory, using + * this flag is ALWAYS memory safe, and will never access out-of-bounds + * memory. However, decompression WILL fail if you violate the preconditions. + * + * WARNING: The data in the ZSTD_outBuffer in the range [dst, dst + pos) MUST + * not be modified during decompression or you will get data corruption. This + * is because zstd needs to reference data in the ZSTD_outBuffer to regenerate + * matches. Normally zstd maintains its own buffer for this purpose, but passing + * this flag tells zstd to use the user provided buffer. + */ +#define ZSTD_d_stableOutBuffer ZSTD_d_experimentalParam2 + +/* ZSTD_d_forceIgnoreChecksum + * Experimental parameter. + * Default is 0 == disabled. Set to 1 to enable + * + * Tells the decompressor to skip checksum validation during decompression, regardless + * of whether checksumming was specified during compression. This offers some + * slight performance benefits, and may be useful for debugging. + * Param has values of type ZSTD_forceIgnoreChecksum_e + */ +#define ZSTD_d_forceIgnoreChecksum ZSTD_d_experimentalParam3 + +/* ZSTD_d_refMultipleDDicts + * Experimental parameter. + * Default is 0 == disabled. Set to 1 to enable + * + * If enabled and dctx is allocated on the heap, then additional memory will be allocated + * to store references to multiple ZSTD_DDict. That is, multiple calls of ZSTD_refDDict() + * using a given ZSTD_DCtx, rather than overwriting the previous DDict reference, will instead + * store all references. At decompression time, the appropriate dictID is selected + * from the set of DDicts based on the dictID in the frame. + * + * Usage is simply calling ZSTD_refDDict() on multiple dict buffers. + * + * Param has values of byte ZSTD_refMultipleDDicts_e + * + * WARNING: Enabling this parameter and calling ZSTD_DCtx_refDDict(), will trigger memory + * allocation for the hash table. ZSTD_freeDCtx() also frees this memory. + * Memory is allocated as per ZSTD_DCtx::customMem. + * + * Although this function allocates memory for the table, the user is still responsible for + * memory management of the underlying ZSTD_DDict* themselves. + */ +#define ZSTD_d_refMultipleDDicts ZSTD_d_experimentalParam4 + +/* ZSTD_d_disableHuffmanAssembly + * Set to 1 to disable the Huffman assembly implementation. + * The default value is 0, which allows zstd to use the Huffman assembly + * implementation if available. + * + * This parameter can be used to disable Huffman assembly at runtime. + * If you want to disable it at compile time you can define the macro + * ZSTD_DISABLE_ASM. + */ +#define ZSTD_d_disableHuffmanAssembly ZSTD_d_experimentalParam5 + +/* ZSTD_d_maxBlockSize + * Allowed values are between 1KB and ZSTD_BLOCKSIZE_MAX (128KB). + * The default is ZSTD_BLOCKSIZE_MAX, and setting to 0 will set to the default. + * + * Forces the decompressor to reject blocks whose content size is + * larger than the configured maxBlockSize. When maxBlockSize is + * larger than the windowSize, the windowSize is used instead. + * This saves memory on the decoder when you know all blocks are small. + * + * This option is typically used in conjunction with ZSTD_c_maxBlockSize. + * + * WARNING: This causes the decoder to reject otherwise valid frames + * that have block sizes larger than the configured maxBlockSize. + */ +#define ZSTD_d_maxBlockSize ZSTD_d_experimentalParam6 + + +/*! 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()). */ +ZSTD_DEPRECATED("use ZSTD_DCtx_setParameter() instead") +ZSTDLIB_STATIC_API +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. + */ +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); + + +/******************************************************************** +* 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. +********************************************************************/ + +/*===== 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. + * This prototype will generate compilation warnings. + */ +ZSTD_DEPRECATED("use ZSTD_CCtx_reset, see zstd.h for detailed instructions") +ZSTDLIB_STATIC_API +size_t ZSTD_initCStream_srcSize(ZSTD_CStream* zcs, + int compressionLevel, + unsigned long long pledgedSrcSize); + +/*! 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. + * 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. + * This prototype will generate compilation warnings. + */ +ZSTD_DEPRECATED("use ZSTD_CCtx_reset, see zstd.h for detailed instructions") +ZSTDLIB_STATIC_API +size_t ZSTD_initCStream_usingDict(ZSTD_CStream* zcs, + const void* dict, size_t dictSize, + int compressionLevel); + +/*! ZSTD_initCStream_advanced() : + * This function is DEPRECATED, and is equivalent to: + * ZSTD_CCtx_reset(zcs, ZSTD_reset_session_only); + * ZSTD_CCtx_setParams(zcs, params); + * 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") +ZSTDLIB_STATIC_API +size_t ZSTD_initCStream_advanced(ZSTD_CStream* zcs, + const void* dict, size_t dictSize, + ZSTD_parameters params, + unsigned long long pledgedSrcSize); + +/*! ZSTD_initCStream_usingCDict() : + * This function is DEPRECATED, and equivalent to: + * ZSTD_CCtx_reset(zcs, ZSTD_reset_session_only); + * ZSTD_CCtx_refCDict(zcs, cdict); + * + * 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") +ZSTDLIB_STATIC_API +size_t ZSTD_initCStream_usingCDict(ZSTD_CStream* zcs, const ZSTD_CDict* cdict); + +/*! ZSTD_initCStream_usingCDict_advanced() : + * This function is DEPRECATED, and is equivalent to: + * ZSTD_CCtx_reset(zcs, ZSTD_reset_session_only); + * ZSTD_CCtx_setFParams(zcs, fParams); + * 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") +ZSTDLIB_STATIC_API +size_t ZSTD_initCStream_usingCDict_advanced(ZSTD_CStream* zcs, + const ZSTD_CDict* cdict, + ZSTD_frameParameters fParams, + unsigned long long pledgedSrcSize); + +/*! ZSTD_resetCStream() : + * This function is DEPRECATED, and is equivalent to: + * 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 reuse 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()) + * This prototype will generate compilation warnings. + */ +ZSTD_DEPRECATED("use ZSTD_CCtx_reset, see zstd.h for detailed instructions") +ZSTDLIB_STATIC_API +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 */ +} ZSTD_frameProgression; + +/* 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. + */ +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. + */ +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 + */ +ZSTD_DEPRECATED("use ZSTD_DCtx_reset + ZSTD_DCtx_loadDictionary, see zstd.h for detailed instructions") +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 + */ +ZSTD_DEPRECATED("use ZSTD_DCtx_reset + ZSTD_DCtx_refDDict, see zstd.h for detailed instructions") +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); + * + * reuse decompression parameters from previous init; saves dictionary loading + */ +ZSTD_DEPRECATED("use ZSTD_DCtx_reset, see zstd.h for detailed instructions") +ZSTDLIB_STATIC_API size_t ZSTD_resetDStream(ZSTD_DStream* zds); + + +/* ********************* BLOCK-LEVEL SEQUENCE PRODUCER API ********************* + * + * *** OVERVIEW *** + * The Block-Level Sequence Producer API allows users to provide their own custom + * sequence producer which libzstd invokes to process each block. The produced list + * of sequences (literals and matches) is then post-processed by libzstd to produce + * valid compressed blocks. + * + * This block-level offload API is a more granular complement of the existing + * frame-level offload API compressSequences() (introduced in v1.5.1). It offers + * an easier migration story for applications already integrated with libzstd: the + * user application continues to invoke the same compression functions + * ZSTD_compress2() or ZSTD_compressStream2() as usual, and transparently benefits + * from the specific advantages of the external sequence producer. For example, + * the sequence producer could be tuned to take advantage of known characteristics + * of the input, to offer better speed / ratio, or could leverage hardware + * acceleration not available within libzstd itself. + * + * See contrib/externalSequenceProducer for an example program employing the + * Block-Level Sequence Producer API. + * + * *** USAGE *** + * The user is responsible for implementing a function of type + * ZSTD_sequenceProducer_F. For each block, zstd will pass the following + * arguments to the user-provided function: + * + * - sequenceProducerState: a pointer to a user-managed state for the sequence + * producer. + * + * - outSeqs, outSeqsCapacity: an output buffer for the sequence producer. + * outSeqsCapacity is guaranteed >= ZSTD_sequenceBound(srcSize). The memory + * backing outSeqs is managed by the CCtx. + * + * - src, srcSize: an input buffer for the sequence producer to parse. + * srcSize is guaranteed to be <= ZSTD_BLOCKSIZE_MAX. + * + * - dict, dictSize: a history buffer, which may be empty, which the sequence + * producer may reference as it parses the src buffer. Currently, zstd will + * always pass dictSize == 0 into external sequence producers, but this will + * change in the future. + * + * - compressionLevel: a signed integer representing the zstd compression level + * set by the user for the current operation. The sequence producer may choose + * to use this information to change its compression strategy and speed/ratio + * tradeoff. Note: the compression level does not reflect zstd parameters set + * through the advanced API. + * + * - windowSize: a size_t representing the maximum allowed offset for external + * sequences. Note that sequence offsets are sometimes allowed to exceed the + * windowSize if a dictionary is present, see doc/zstd_compression_format.md + * for details. + * + * The user-provided function shall return a size_t representing the number of + * sequences written to outSeqs. This return value will be treated as an error + * code if it is greater than outSeqsCapacity. The return value must be non-zero + * if srcSize is non-zero. The ZSTD_SEQUENCE_PRODUCER_ERROR macro is provided + * for convenience, but any value greater than outSeqsCapacity will be treated as + * an error code. + * + * If the user-provided function does not return an error code, the sequences + * written to outSeqs must be a valid parse of the src buffer. Data corruption may + * occur if the parse is not valid. A parse is defined to be valid if the + * following conditions hold: + * - The sum of matchLengths and literalLengths must equal srcSize. + * - All sequences in the parse, except for the final sequence, must have + * matchLength >= ZSTD_MINMATCH_MIN. The final sequence must have + * matchLength >= ZSTD_MINMATCH_MIN or matchLength == 0. + * - All offsets must respect the windowSize parameter as specified in + * doc/zstd_compression_format.md. + * - If the final sequence has matchLength == 0, it must also have offset == 0. + * + * zstd will only validate these conditions (and fail compression if they do not + * hold) if the ZSTD_c_validateSequences cParam is enabled. Note that sequence + * validation has a performance cost. + * + * If the user-provided function returns an error, zstd will either fall back + * to an internal sequence producer or fail the compression operation. The user can + * choose between the two behaviors by setting the ZSTD_c_enableSeqProducerFallback + * cParam. Fallback compression will follow any other cParam settings, such as + * compression level, the same as in a normal compression operation. + * + * The user shall instruct zstd to use a particular ZSTD_sequenceProducer_F + * function by calling + * ZSTD_registerSequenceProducer(cctx, + * sequenceProducerState, + * sequenceProducer) + * This setting will persist until the next parameter reset of the CCtx. + * + * The sequenceProducerState must be initialized by the user before calling + * ZSTD_registerSequenceProducer(). The user is responsible for destroying the + * sequenceProducerState. + * + * *** LIMITATIONS *** + * This API is compatible with all zstd compression APIs which respect advanced parameters. + * However, there are three limitations: + * + * First, the ZSTD_c_enableLongDistanceMatching cParam is not currently supported. + * COMPRESSION WILL FAIL if it is enabled and the user tries to compress with a block-level + * external sequence producer. + * - Note that ZSTD_c_enableLongDistanceMatching is auto-enabled by default in some + * cases (see its documentation for details). Users must explicitly set + * ZSTD_c_enableLongDistanceMatching to ZSTD_ps_disable in such cases if an external + * sequence producer is registered. + * - As of this writing, ZSTD_c_enableLongDistanceMatching is disabled by default + * whenever ZSTD_c_windowLog < 128MB, but that's subject to change. Users should + * check the docs on ZSTD_c_enableLongDistanceMatching whenever the Block-Level Sequence + * Producer API is used in conjunction with advanced settings (like ZSTD_c_windowLog). + * + * Second, history buffers are not currently supported. Concretely, zstd will always pass + * dictSize == 0 to the external sequence producer (for now). This has two implications: + * - Dictionaries are not currently supported. Compression will *not* fail if the user + * references a dictionary, but the dictionary won't have any effect. + * - Stream history is not currently supported. All advanced compression APIs, including + * streaming APIs, work with external sequence producers, but each block is treated as + * an independent chunk without history from previous blocks. + * + * Third, multi-threading within a single compression is not currently supported. In other words, + * COMPRESSION WILL FAIL if ZSTD_c_nbWorkers > 0 and an external sequence producer is registered. + * Multi-threading across compressions is fine: simply create one CCtx per thread. + * + * Long-term, we plan to overcome all three limitations. There is no technical blocker to + * overcoming them. It is purely a question of engineering effort. + */ + +#define ZSTD_SEQUENCE_PRODUCER_ERROR ((size_t)(-1)) + +typedef size_t (*ZSTD_sequenceProducer_F) ( + void* sequenceProducerState, + ZSTD_Sequence* outSeqs, size_t outSeqsCapacity, + const void* src, size_t srcSize, + const void* dict, size_t dictSize, + int compressionLevel, + size_t windowSize +); + +/*! ZSTD_registerSequenceProducer() : + * Instruct zstd to use a block-level external sequence producer function. + * + * The sequenceProducerState must be initialized by the caller, and the caller is + * responsible for managing its lifetime. This parameter is sticky across + * compressions. It will remain set until the user explicitly resets compression + * parameters. + * + * Sequence producer registration is considered to be an "advanced parameter", + * part of the "advanced API". This means it will only have an effect on compression + * APIs which respect advanced parameters, such as compress2() and compressStream2(). + * Older compression APIs such as compressCCtx(), which predate the introduction of + * "advanced parameters", will ignore any external sequence producer setting. + * + * The sequence producer can be "cleared" by registering a NULL function pointer. This + * removes all limitations described above in the "LIMITATIONS" section of the API docs. + * + * The user is strongly encouraged to read the full API documentation (above) before + * calling this function. */ +ZSTDLIB_STATIC_API void +ZSTD_registerSequenceProducer( + ZSTD_CCtx* cctx, + void* sequenceProducerState, + ZSTD_sequenceProducer_F sequenceProducer +); + +/*! ZSTD_CCtxParams_registerSequenceProducer() : + * Same as ZSTD_registerSequenceProducer(), but operates on ZSTD_CCtx_params. + * This is used for accurate size estimation with ZSTD_estimateCCtxSize_usingCCtxParams(), + * which is needed when creating a ZSTD_CCtx with ZSTD_initStaticCCtx(). + * + * If you are using the external sequence producer API in a scenario where ZSTD_initStaticCCtx() + * is required, then this function is for you. Otherwise, you probably don't need it. + * + * See tests/zstreamtest.c for example usage. */ +ZSTDLIB_STATIC_API void +ZSTD_CCtxParams_registerSequenceProducer( + ZSTD_CCtx_params* params, + void* sequenceProducerState, + ZSTD_sequenceProducer_F sequenceProducer +); + + +/********************************************************************* +* Buffer-less and synchronous inner streaming functions (DEPRECATED) +* +* This API is deprecated, and will be removed in a future version. +* It allows streaming (de)compression with user allocated buffers. +* However, it is hard to use, and not as well tested as the rest of +* our API. +* +* Please use the normal streaming API instead: ZSTD_compressStream2, +* and ZSTD_decompressStream. +* If there is functionality that you need, but it doesn't provide, +* please open an issue on our GitHub. +********************************************************************* */ + +/** + Buffer-less streaming compression (synchronous mode) + + A ZSTD_CCtx object is required to track streaming operations. + Use ZSTD_createCCtx() / ZSTD_freeCCtx() to manage resource. + ZSTD_CCtx object can be reused multiple times within successive compression operations. + + Start by initializing a context. + Use ZSTD_compressBegin(), or ZSTD_compressBegin_usingDict() for dictionary compression. + + Then, consume your input using ZSTD_compressContinue(). + There are some important considerations to keep in mind when using this advanced function : + - ZSTD_compressContinue() has no internal buffer. It uses externally provided buffers only. + - Interface is synchronous : input is consumed entirely and produces 1+ compressed blocks. + - Caller must ensure there is enough space in `dst` to store compressed data under worst case scenario. + Worst case evaluation is provided by ZSTD_compressBound(). + ZSTD_compressContinue() doesn't guarantee recover after a failed compression. + - ZSTD_compressContinue() presumes prior input ***is still accessible and unmodified*** (up to maximum distance size, see WindowLog). + It remembers all previous contiguous blocks, plus one separated memory segment (which can itself consists of multiple contiguous blocks) + - ZSTD_compressContinue() detects that prior input has been overwritten when `src` buffer overlaps. + In which case, it will "discard" the relevant memory section from its history. + + Finish a frame with ZSTD_compressEnd(), which will write the last block(s) and optional checksum. + It's possible to use srcSize==0, in which case, it will write a final empty block to end the frame. + Without last block mark, frames are considered unfinished (hence corrupted) by compliant decoders. + + `ZSTD_CCtx` object can be reused (ZSTD_compressBegin()) to compress again. +*/ + +/*===== Buffer-less streaming compression functions =====*/ +ZSTD_DEPRECATED("The buffer-less API is deprecated in favor of the normal streaming API. See docs.") +ZSTDLIB_STATIC_API size_t ZSTD_compressBegin(ZSTD_CCtx* cctx, int compressionLevel); +ZSTD_DEPRECATED("The buffer-less API is deprecated in favor of the normal streaming API. See docs.") +ZSTDLIB_STATIC_API size_t ZSTD_compressBegin_usingDict(ZSTD_CCtx* cctx, const void* dict, size_t dictSize, int compressionLevel); +ZSTD_DEPRECATED("The buffer-less API is deprecated in favor of the normal streaming API. See docs.") +ZSTDLIB_STATIC_API size_t ZSTD_compressBegin_usingCDict(ZSTD_CCtx* cctx, const ZSTD_CDict* cdict); /**< note: fails if cdict==NULL */ + +ZSTD_DEPRECATED("This function will likely be removed in a future release. It is misleading and has very limited utility.") +ZSTDLIB_STATIC_API +size_t ZSTD_copyCCtx(ZSTD_CCtx* cctx, const ZSTD_CCtx* preparedCCtx, unsigned long long pledgedSrcSize); /**< note: if pledgedSrcSize is not known, use ZSTD_CONTENTSIZE_UNKNOWN */ + +ZSTD_DEPRECATED("The buffer-less API is deprecated in favor of the normal streaming API. See docs.") +ZSTDLIB_STATIC_API size_t ZSTD_compressContinue(ZSTD_CCtx* cctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize); +ZSTD_DEPRECATED("The buffer-less API is deprecated in favor of the normal streaming API. See docs.") +ZSTDLIB_STATIC_API size_t ZSTD_compressEnd(ZSTD_CCtx* cctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize); + +/* The ZSTD_compressBegin_advanced() and ZSTD_compressBegin_usingCDict_advanced() are now DEPRECATED and will generate a compiler warning */ +ZSTD_DEPRECATED("use advanced API to access custom parameters") +ZSTDLIB_STATIC_API +size_t ZSTD_compressBegin_advanced(ZSTD_CCtx* cctx, const void* dict, size_t dictSize, ZSTD_parameters params, unsigned long long pledgedSrcSize); /**< pledgedSrcSize : If srcSize is not known at init time, use ZSTD_CONTENTSIZE_UNKNOWN */ +ZSTD_DEPRECATED("use advanced API to access custom parameters") +ZSTDLIB_STATIC_API +size_t ZSTD_compressBegin_usingCDict_advanced(ZSTD_CCtx* const cctx, const ZSTD_CDict* const cdict, ZSTD_frameParameters const fParams, unsigned long long const pledgedSrcSize); /* compression parameters are already set within cdict. pledgedSrcSize must be correct. If srcSize is not known, use macro ZSTD_CONTENTSIZE_UNKNOWN */ +/** + Buffer-less streaming decompression (synchronous mode) + + A ZSTD_DCtx object is required to track streaming operations. + Use ZSTD_createDCtx() / ZSTD_freeDCtx() to manage it. + A ZSTD_DCtx object can be reused multiple times. + + First typical operation is to retrieve frame parameters, using ZSTD_getFrameHeader(). + Frame header is extracted from the beginning of compressed frame, so providing only the frame's beginning is enough. + Data fragment must be large enough to ensure successful decoding. + `ZSTD_frameHeaderSize_max` bytes is guaranteed to always be large enough. + result : 0 : successful decoding, the `ZSTD_frameHeader` structure is correctly filled. + >0 : `srcSize` is too small, please provide at least result bytes on next attempt. + errorCode, which can be tested using ZSTD_isError(). + + It fills a ZSTD_frameHeader structure with important information to correctly decode the frame, + such as the dictionary ID, content size, or maximum back-reference distance (`windowSize`). + Note that these values could be wrong, either because of data corruption, or because a 3rd party deliberately spoofs false information. + As a consequence, check that values remain within valid application range. + For example, do not allocate memory blindly, check that `windowSize` is within expectation. + Each application can set its own limits, depending on local restrictions. + For extended interoperability, it is recommended to support `windowSize` of at least 8 MB. + + ZSTD_decompressContinue() needs previous data blocks during decompression, up to `windowSize` bytes. + ZSTD_decompressContinue() is very sensitive to contiguity, + if 2 blocks don't follow each other, make sure that either the compressor breaks contiguity at the same place, + or that previous contiguous segment is large enough to properly handle maximum back-reference distance. + There are multiple ways to guarantee this condition. + + The most memory efficient way is to use a round buffer of sufficient size. + Sufficient size is determined by invoking ZSTD_decodingBufferSize_min(), + which can return an error code if required value is too large for current system (in 32-bits mode). + In a round buffer methodology, ZSTD_decompressContinue() decompresses each block next to previous one, + up to the moment there is not enough room left in the buffer to guarantee decoding another full block, + which maximum size is provided in `ZSTD_frameHeader` structure, field `blockSizeMax`. + At which point, decoding can resume from the beginning of the buffer. + Note that already decoded data stored in the buffer should be flushed before being overwritten. + + There are alternatives possible, for example using two or more buffers of size `windowSize` each, though they consume more memory. + + Finally, if you control the compression process, you can also ignore all buffer size rules, + as long as the encoder and decoder progress in "lock-step", + aka use exactly the same buffer sizes, break contiguity at the same place, etc. + + Once buffers are setup, start decompression, with ZSTD_decompressBegin(). + If decompression requires a dictionary, use ZSTD_decompressBegin_usingDict() or ZSTD_decompressBegin_usingDDict(). + + Then use ZSTD_nextSrcSizeToDecompress() and ZSTD_decompressContinue() alternatively. + ZSTD_nextSrcSizeToDecompress() tells how many bytes to provide as 'srcSize' to ZSTD_decompressContinue(). + ZSTD_decompressContinue() requires this _exact_ amount of bytes, or it will fail. + + result of ZSTD_decompressContinue() is the number of bytes regenerated within 'dst' (necessarily <= dstCapacity). + It can be zero : it just means ZSTD_decompressContinue() has decoded some metadata item. + It can also be an error code, which can be tested with ZSTD_isError(). + + A frame is fully decoded when ZSTD_nextSrcSizeToDecompress() returns zero. + Context can then be reset to start a new decompression. + + Note : it's possible to know if next input to present is a header or a block, using ZSTD_nextInputType(). + This information is not required to properly decode a frame. + + == Special case : skippable frames == + + Skippable frames allow integration of user-defined data into a flow of concatenated frames. + Skippable frames will be ignored (skipped) by decompressor. + The format of skippable frames is as follows : + a) Skippable frame ID - 4 Bytes, Little endian format, any value from 0x184D2A50 to 0x184D2A5F + b) Frame Size - 4 Bytes, Little endian format, unsigned 32-bits + c) Frame Content - any content (User Data) of length equal to Frame Size + For skippable frames ZSTD_getFrameHeader() returns zfhPtr->frameType==ZSTD_skippableFrame. + For skippable frames ZSTD_decompressContinue() always returns 0 : it only skips the content. +*/ + +/*===== Buffer-less streaming decompression functions =====*/ + +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 */ + +ZSTDLIB_STATIC_API size_t ZSTD_decompressBegin(ZSTD_DCtx* dctx); +ZSTDLIB_STATIC_API size_t ZSTD_decompressBegin_usingDict(ZSTD_DCtx* dctx, const void* dict, size_t dictSize); +ZSTDLIB_STATIC_API size_t ZSTD_decompressBegin_usingDDict(ZSTD_DCtx* dctx, const ZSTD_DDict* ddict); + +ZSTDLIB_STATIC_API size_t ZSTD_nextSrcSizeToDecompress(ZSTD_DCtx* dctx); +ZSTDLIB_STATIC_API size_t ZSTD_decompressContinue(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize); + +/* misc */ +ZSTD_DEPRECATED("This function will likely be removed in the next minor release. It is misleading and has very limited utility.") +ZSTDLIB_STATIC_API void ZSTD_copyDCtx(ZSTD_DCtx* dctx, const ZSTD_DCtx* preparedDCtx); +typedef enum { ZSTDnit_frameHeader, ZSTDnit_blockHeader, ZSTDnit_block, ZSTDnit_lastBlock, ZSTDnit_checksum, ZSTDnit_skippableFrame } ZSTD_nextInputType_e; +ZSTDLIB_STATIC_API ZSTD_nextInputType_e ZSTD_nextInputType(ZSTD_DCtx* dctx); + + + + +/* ========================================= */ +/** Block level API (DEPRECATED) */ +/* ========================================= */ + +/*! + + This API is deprecated in favor of the regular compression API. + You can get the frame header down to 2 bytes by setting: + - ZSTD_c_format = ZSTD_f_zstd1_magicless + - ZSTD_c_contentSizeFlag = 0 + - ZSTD_c_checksumFlag = 0 + - ZSTD_c_dictIDFlag = 0 + + This API is not as well tested as our normal API, so we recommend not using it. + We will be removing it in a future version. If the normal API doesn't provide + the functionality you need, please open a GitHub issue. + + Block functions produce and decode raw zstd blocks, without frame metadata. + Frame metadata cost is typically ~12 bytes, which can be non-negligible for very small blocks (< 100 bytes). + But users will have to take in charge needed metadata to regenerate data, such as compressed and content sizes. + + A few rules to respect : + - Compressing and decompressing require a context structure + + Use ZSTD_createCCtx() and ZSTD_createDCtx() + - It is necessary to init context before starting + + compression : any ZSTD_compressBegin*() variant, including with dictionary + + decompression : any ZSTD_decompressBegin*() variant, including with dictionary + - Block size is limited, it must be <= ZSTD_getBlockSize() <= ZSTD_BLOCKSIZE_MAX == 128 KB + + If input is larger than a block size, it's necessary to split input data into multiple blocks + + For inputs larger than a single block, consider using regular ZSTD_compress() instead. + Frame metadata is not that costly, and quickly becomes negligible as source size grows larger than a block. + - When a block is considered not compressible enough, ZSTD_compressBlock() result will be 0 (zero) ! + ===> In which case, nothing is produced into `dst` ! + + User __must__ test for such outcome and deal directly with uncompressed data + + A block cannot be declared incompressible if ZSTD_compressBlock() return value was != 0. + Doing so would mess up with statistics history, leading to potential data corruption. + + ZSTD_decompressBlock() _doesn't accept uncompressed data as input_ !! + + In case of multiple successive blocks, should some of them be uncompressed, + decoder must be informed of their existence in order to follow proper history. + Use ZSTD_insertBlock() for such a case. +*/ + +/*===== Raw zstd block functions =====*/ +ZSTD_DEPRECATED("The block API is deprecated in favor of the normal compression API. See docs.") +ZSTDLIB_STATIC_API size_t ZSTD_getBlockSize (const ZSTD_CCtx* cctx); +ZSTD_DEPRECATED("The block API is deprecated in favor of the normal compression API. See docs.") +ZSTDLIB_STATIC_API size_t ZSTD_compressBlock (ZSTD_CCtx* cctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize); +ZSTD_DEPRECATED("The block API is deprecated in favor of the normal compression API. See docs.") +ZSTDLIB_STATIC_API size_t ZSTD_decompressBlock(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize); +ZSTD_DEPRECATED("The block API is deprecated in favor of the normal compression API. See docs.") +ZSTDLIB_STATIC_API size_t ZSTD_insertBlock (ZSTD_DCtx* dctx, const void* blockStart, size_t blockSize); /**< insert uncompressed block into `dctx` history. Useful for multi-blocks decompression. */ + +#endif /* ZSTD_H_ZSTD_STATIC_LINKING_ONLY */ + +#if defined (__cplusplus) +} +#endif +