1*a28cd43dSSascha Wildner /* 2*a28cd43dSSascha Wildner * Copyright (c) 2016-2020, Yann Collet, Facebook, Inc. 3*a28cd43dSSascha Wildner * All rights reserved. 4*a28cd43dSSascha Wildner * 5*a28cd43dSSascha Wildner * This source code is licensed under both the BSD-style license (found in the 6*a28cd43dSSascha Wildner * LICENSE file in the root directory of this source tree) and the GPLv2 (found 7*a28cd43dSSascha Wildner * in the COPYING file in the root directory of this source tree). 8*a28cd43dSSascha Wildner * You may select, at your option, one of the above-listed licenses. 9*a28cd43dSSascha Wildner */ 10*a28cd43dSSascha Wildner 11*a28cd43dSSascha Wildner #ifndef DICTBUILDER_H_001 12*a28cd43dSSascha Wildner #define DICTBUILDER_H_001 13*a28cd43dSSascha Wildner 14*a28cd43dSSascha Wildner #if defined (__cplusplus) 15*a28cd43dSSascha Wildner extern "C" { 16*a28cd43dSSascha Wildner #endif 17*a28cd43dSSascha Wildner 18*a28cd43dSSascha Wildner 19*a28cd43dSSascha Wildner /*====== Dependencies ======*/ 20*a28cd43dSSascha Wildner #include <stddef.h> /* size_t */ 21*a28cd43dSSascha Wildner 22*a28cd43dSSascha Wildner 23*a28cd43dSSascha Wildner /* ===== ZDICTLIB_API : control library symbols visibility ===== */ 24*a28cd43dSSascha Wildner #ifndef ZDICTLIB_VISIBILITY 25*a28cd43dSSascha Wildner # if defined(__GNUC__) && (__GNUC__ >= 4) 26*a28cd43dSSascha Wildner # define ZDICTLIB_VISIBILITY __attribute__ ((visibility ("default"))) 27*a28cd43dSSascha Wildner # else 28*a28cd43dSSascha Wildner # define ZDICTLIB_VISIBILITY 29*a28cd43dSSascha Wildner # endif 30*a28cd43dSSascha Wildner #endif 31*a28cd43dSSascha Wildner #if defined(ZSTD_DLL_EXPORT) && (ZSTD_DLL_EXPORT==1) 32*a28cd43dSSascha Wildner # define ZDICTLIB_API __declspec(dllexport) ZDICTLIB_VISIBILITY 33*a28cd43dSSascha Wildner #elif defined(ZSTD_DLL_IMPORT) && (ZSTD_DLL_IMPORT==1) 34*a28cd43dSSascha Wildner # define ZDICTLIB_API __declspec(dllimport) ZDICTLIB_VISIBILITY /* It isn't required but allows to generate better code, saving a function pointer load from the IAT and an indirect jump.*/ 35*a28cd43dSSascha Wildner #else 36*a28cd43dSSascha Wildner # define ZDICTLIB_API ZDICTLIB_VISIBILITY 37*a28cd43dSSascha Wildner #endif 38*a28cd43dSSascha Wildner 39*a28cd43dSSascha Wildner 40*a28cd43dSSascha Wildner /*! ZDICT_trainFromBuffer(): 41*a28cd43dSSascha Wildner * Train a dictionary from an array of samples. 42*a28cd43dSSascha Wildner * Redirect towards ZDICT_optimizeTrainFromBuffer_fastCover() single-threaded, with d=8, steps=4, 43*a28cd43dSSascha Wildner * f=20, and accel=1. 44*a28cd43dSSascha Wildner * Samples must be stored concatenated in a single flat buffer `samplesBuffer`, 45*a28cd43dSSascha Wildner * supplied with an array of sizes `samplesSizes`, providing the size of each sample, in order. 46*a28cd43dSSascha Wildner * The resulting dictionary will be saved into `dictBuffer`. 47*a28cd43dSSascha Wildner * @return: size of dictionary stored into `dictBuffer` (<= `dictBufferCapacity`) 48*a28cd43dSSascha Wildner * or an error code, which can be tested with ZDICT_isError(). 49*a28cd43dSSascha Wildner * Note: Dictionary training will fail if there are not enough samples to construct a 50*a28cd43dSSascha Wildner * dictionary, or if most of the samples are too small (< 8 bytes being the lower limit). 51*a28cd43dSSascha Wildner * If dictionary training fails, you should use zstd without a dictionary, as the dictionary 52*a28cd43dSSascha Wildner * would've been ineffective anyways. If you believe your samples would benefit from a dictionary 53*a28cd43dSSascha Wildner * please open an issue with details, and we can look into it. 54*a28cd43dSSascha Wildner * Note: ZDICT_trainFromBuffer()'s memory usage is about 6 MB. 55*a28cd43dSSascha Wildner * Tips: In general, a reasonable dictionary has a size of ~ 100 KB. 56*a28cd43dSSascha Wildner * It's possible to select smaller or larger size, just by specifying `dictBufferCapacity`. 57*a28cd43dSSascha Wildner * In general, it's recommended to provide a few thousands samples, though this can vary a lot. 58*a28cd43dSSascha Wildner * It's recommended that total size of all samples be about ~x100 times the target size of dictionary. 59*a28cd43dSSascha Wildner */ 60*a28cd43dSSascha Wildner ZDICTLIB_API size_t ZDICT_trainFromBuffer(void* dictBuffer, size_t dictBufferCapacity, 61*a28cd43dSSascha Wildner const void* samplesBuffer, 62*a28cd43dSSascha Wildner const size_t* samplesSizes, unsigned nbSamples); 63*a28cd43dSSascha Wildner 64*a28cd43dSSascha Wildner typedef struct { 65*a28cd43dSSascha Wildner int compressionLevel; /*< optimize for a specific zstd compression level; 0 means default */ 66*a28cd43dSSascha Wildner unsigned notificationLevel; /*< Write log to stderr; 0 = none (default); 1 = errors; 2 = progression; 3 = details; 4 = debug; */ 67*a28cd43dSSascha Wildner unsigned dictID; /*< force dictID value; 0 means auto mode (32-bits random value) */ 68*a28cd43dSSascha Wildner } ZDICT_params_t; 69*a28cd43dSSascha Wildner 70*a28cd43dSSascha Wildner /*! ZDICT_finalizeDictionary(): 71*a28cd43dSSascha Wildner * Given a custom content as a basis for dictionary, and a set of samples, 72*a28cd43dSSascha Wildner * finalize dictionary by adding headers and statistics according to the zstd 73*a28cd43dSSascha Wildner * dictionary format. 74*a28cd43dSSascha Wildner * 75*a28cd43dSSascha Wildner * Samples must be stored concatenated in a flat buffer `samplesBuffer`, 76*a28cd43dSSascha Wildner * supplied with an array of sizes `samplesSizes`, providing the size of each 77*a28cd43dSSascha Wildner * sample in order. The samples are used to construct the statistics, so they 78*a28cd43dSSascha Wildner * should be representative of what you will compress with this dictionary. 79*a28cd43dSSascha Wildner * 80*a28cd43dSSascha Wildner * The compression level can be set in `parameters`. You should pass the 81*a28cd43dSSascha Wildner * compression level you expect to use in production. The statistics for each 82*a28cd43dSSascha Wildner * compression level differ, so tuning the dictionary for the compression level 83*a28cd43dSSascha Wildner * can help quite a bit. 84*a28cd43dSSascha Wildner * 85*a28cd43dSSascha Wildner * You can set an explicit dictionary ID in `parameters`, or allow us to pick 86*a28cd43dSSascha Wildner * a random dictionary ID for you, but we can't guarantee no collisions. 87*a28cd43dSSascha Wildner * 88*a28cd43dSSascha Wildner * The dstDictBuffer and the dictContent may overlap, and the content will be 89*a28cd43dSSascha Wildner * appended to the end of the header. If the header + the content doesn't fit in 90*a28cd43dSSascha Wildner * maxDictSize the beginning of the content is truncated to make room, since it 91*a28cd43dSSascha Wildner * is presumed that the most profitable content is at the end of the dictionary, 92*a28cd43dSSascha Wildner * since that is the cheapest to reference. 93*a28cd43dSSascha Wildner * 94*a28cd43dSSascha Wildner * `dictContentSize` must be >= ZDICT_CONTENTSIZE_MIN bytes. 95*a28cd43dSSascha Wildner * `maxDictSize` must be >= max(dictContentSize, ZSTD_DICTSIZE_MIN). 96*a28cd43dSSascha Wildner * 97*a28cd43dSSascha Wildner * @return: size of dictionary stored into `dstDictBuffer` (<= `maxDictSize`), 98*a28cd43dSSascha Wildner * or an error code, which can be tested by ZDICT_isError(). 99*a28cd43dSSascha Wildner * Note: ZDICT_finalizeDictionary() will push notifications into stderr if 100*a28cd43dSSascha Wildner * instructed to, using notificationLevel>0. 101*a28cd43dSSascha Wildner * NOTE: This function currently may fail in several edge cases including: 102*a28cd43dSSascha Wildner * * Not enough samples 103*a28cd43dSSascha Wildner * * Samples are uncompressible 104*a28cd43dSSascha Wildner * * Samples are all exactly the same 105*a28cd43dSSascha Wildner */ 106*a28cd43dSSascha Wildner ZDICTLIB_API size_t ZDICT_finalizeDictionary(void* dstDictBuffer, size_t maxDictSize, 107*a28cd43dSSascha Wildner const void* dictContent, size_t dictContentSize, 108*a28cd43dSSascha Wildner const void* samplesBuffer, const size_t* samplesSizes, unsigned nbSamples, 109*a28cd43dSSascha Wildner ZDICT_params_t parameters); 110*a28cd43dSSascha Wildner 111*a28cd43dSSascha Wildner 112*a28cd43dSSascha Wildner /*====== Helper functions ======*/ 113*a28cd43dSSascha Wildner ZDICTLIB_API unsigned ZDICT_getDictID(const void* dictBuffer, size_t dictSize); /**< extracts dictID; @return zero if error (not a valid dictionary) */ 114*a28cd43dSSascha Wildner ZDICTLIB_API size_t ZDICT_getDictHeaderSize(const void* dictBuffer, size_t dictSize); /* returns dict header size; returns a ZSTD error code on failure */ 115*a28cd43dSSascha Wildner ZDICTLIB_API unsigned ZDICT_isError(size_t errorCode); 116*a28cd43dSSascha Wildner ZDICTLIB_API const char* ZDICT_getErrorName(size_t errorCode); 117*a28cd43dSSascha Wildner 118*a28cd43dSSascha Wildner 119*a28cd43dSSascha Wildner 120*a28cd43dSSascha Wildner #ifdef ZDICT_STATIC_LINKING_ONLY 121*a28cd43dSSascha Wildner 122*a28cd43dSSascha Wildner /* ==================================================================================== 123*a28cd43dSSascha Wildner * The definitions in this section are considered experimental. 124*a28cd43dSSascha Wildner * They should never be used with a dynamic library, as they may change in the future. 125*a28cd43dSSascha Wildner * They are provided for advanced usages. 126*a28cd43dSSascha Wildner * Use them only in association with static linking. 127*a28cd43dSSascha Wildner * ==================================================================================== */ 128*a28cd43dSSascha Wildner 129*a28cd43dSSascha Wildner #define ZDICT_CONTENTSIZE_MIN 128 130*a28cd43dSSascha Wildner #define ZDICT_DICTSIZE_MIN 256 131*a28cd43dSSascha Wildner 132*a28cd43dSSascha Wildner /*! ZDICT_cover_params_t: 133*a28cd43dSSascha Wildner * k and d are the only required parameters. 134*a28cd43dSSascha Wildner * For others, value 0 means default. 135*a28cd43dSSascha Wildner */ 136*a28cd43dSSascha Wildner typedef struct { 137*a28cd43dSSascha Wildner unsigned k; /* Segment size : constraint: 0 < k : Reasonable range [16, 2048+] */ 138*a28cd43dSSascha Wildner unsigned d; /* dmer size : constraint: 0 < d <= k : Reasonable range [6, 16] */ 139*a28cd43dSSascha Wildner unsigned steps; /* Number of steps : Only used for optimization : 0 means default (40) : Higher means more parameters checked */ 140*a28cd43dSSascha Wildner unsigned nbThreads; /* Number of threads : constraint: 0 < nbThreads : 1 means single-threaded : Only used for optimization : Ignored if ZSTD_MULTITHREAD is not defined */ 141*a28cd43dSSascha Wildner double splitPoint; /* Percentage of samples used for training: Only used for optimization : the first nbSamples * splitPoint samples will be used to training, the last nbSamples * (1 - splitPoint) samples will be used for testing, 0 means default (1.0), 1.0 when all samples are used for both training and testing */ 142*a28cd43dSSascha Wildner unsigned shrinkDict; /* Train dictionaries to shrink in size starting from the minimum size and selects the smallest dictionary that is shrinkDictMaxRegression% worse than the largest dictionary. 0 means no shrinking and 1 means shrinking */ 143*a28cd43dSSascha Wildner unsigned shrinkDictMaxRegression; /* Sets shrinkDictMaxRegression so that a smaller dictionary can be at worse shrinkDictMaxRegression% worse than the max dict size dictionary. */ 144*a28cd43dSSascha Wildner ZDICT_params_t zParams; 145*a28cd43dSSascha Wildner } ZDICT_cover_params_t; 146*a28cd43dSSascha Wildner 147*a28cd43dSSascha Wildner typedef struct { 148*a28cd43dSSascha Wildner unsigned k; /* Segment size : constraint: 0 < k : Reasonable range [16, 2048+] */ 149*a28cd43dSSascha Wildner unsigned d; /* dmer size : constraint: 0 < d <= k : Reasonable range [6, 16] */ 150*a28cd43dSSascha Wildner unsigned f; /* log of size of frequency array : constraint: 0 < f <= 31 : 1 means default(20)*/ 151*a28cd43dSSascha Wildner unsigned steps; /* Number of steps : Only used for optimization : 0 means default (40) : Higher means more parameters checked */ 152*a28cd43dSSascha Wildner unsigned nbThreads; /* Number of threads : constraint: 0 < nbThreads : 1 means single-threaded : Only used for optimization : Ignored if ZSTD_MULTITHREAD is not defined */ 153*a28cd43dSSascha Wildner double splitPoint; /* Percentage of samples used for training: Only used for optimization : the first nbSamples * splitPoint samples will be used to training, the last nbSamples * (1 - splitPoint) samples will be used for testing, 0 means default (0.75), 1.0 when all samples are used for both training and testing */ 154*a28cd43dSSascha Wildner unsigned accel; /* Acceleration level: constraint: 0 < accel <= 10, higher means faster and less accurate, 0 means default(1) */ 155*a28cd43dSSascha Wildner unsigned shrinkDict; /* Train dictionaries to shrink in size starting from the minimum size and selects the smallest dictionary that is shrinkDictMaxRegression% worse than the largest dictionary. 0 means no shrinking and 1 means shrinking */ 156*a28cd43dSSascha Wildner unsigned shrinkDictMaxRegression; /* Sets shrinkDictMaxRegression so that a smaller dictionary can be at worse shrinkDictMaxRegression% worse than the max dict size dictionary. */ 157*a28cd43dSSascha Wildner 158*a28cd43dSSascha Wildner ZDICT_params_t zParams; 159*a28cd43dSSascha Wildner } ZDICT_fastCover_params_t; 160*a28cd43dSSascha Wildner 161*a28cd43dSSascha Wildner /*! ZDICT_trainFromBuffer_cover(): 162*a28cd43dSSascha Wildner * Train a dictionary from an array of samples using the COVER algorithm. 163*a28cd43dSSascha Wildner * Samples must be stored concatenated in a single flat buffer `samplesBuffer`, 164*a28cd43dSSascha Wildner * supplied with an array of sizes `samplesSizes`, providing the size of each sample, in order. 165*a28cd43dSSascha Wildner * The resulting dictionary will be saved into `dictBuffer`. 166*a28cd43dSSascha Wildner * @return: size of dictionary stored into `dictBuffer` (<= `dictBufferCapacity`) 167*a28cd43dSSascha Wildner * or an error code, which can be tested with ZDICT_isError(). 168*a28cd43dSSascha Wildner * See ZDICT_trainFromBuffer() for details on failure modes. 169*a28cd43dSSascha Wildner * Note: ZDICT_trainFromBuffer_cover() requires about 9 bytes of memory for each input byte. 170*a28cd43dSSascha Wildner * Tips: In general, a reasonable dictionary has a size of ~ 100 KB. 171*a28cd43dSSascha Wildner * It's possible to select smaller or larger size, just by specifying `dictBufferCapacity`. 172*a28cd43dSSascha Wildner * In general, it's recommended to provide a few thousands samples, though this can vary a lot. 173*a28cd43dSSascha Wildner * It's recommended that total size of all samples be about ~x100 times the target size of dictionary. 174*a28cd43dSSascha Wildner */ 175*a28cd43dSSascha Wildner ZDICTLIB_API size_t ZDICT_trainFromBuffer_cover( 176*a28cd43dSSascha Wildner void *dictBuffer, size_t dictBufferCapacity, 177*a28cd43dSSascha Wildner const void *samplesBuffer, const size_t *samplesSizes, unsigned nbSamples, 178*a28cd43dSSascha Wildner ZDICT_cover_params_t parameters); 179*a28cd43dSSascha Wildner 180*a28cd43dSSascha Wildner /*! ZDICT_optimizeTrainFromBuffer_cover(): 181*a28cd43dSSascha Wildner * The same requirements as above hold for all the parameters except `parameters`. 182*a28cd43dSSascha Wildner * This function tries many parameter combinations and picks the best parameters. 183*a28cd43dSSascha Wildner * `*parameters` is filled with the best parameters found, 184*a28cd43dSSascha Wildner * dictionary constructed with those parameters is stored in `dictBuffer`. 185*a28cd43dSSascha Wildner * 186*a28cd43dSSascha Wildner * All of the parameters d, k, steps are optional. 187*a28cd43dSSascha Wildner * If d is non-zero then we don't check multiple values of d, otherwise we check d = {6, 8}. 188*a28cd43dSSascha Wildner * if steps is zero it defaults to its default value. 189*a28cd43dSSascha Wildner * If k is non-zero then we don't check multiple values of k, otherwise we check steps values in [50, 2000]. 190*a28cd43dSSascha Wildner * 191*a28cd43dSSascha Wildner * @return: size of dictionary stored into `dictBuffer` (<= `dictBufferCapacity`) 192*a28cd43dSSascha Wildner * or an error code, which can be tested with ZDICT_isError(). 193*a28cd43dSSascha Wildner * On success `*parameters` contains the parameters selected. 194*a28cd43dSSascha Wildner * See ZDICT_trainFromBuffer() for details on failure modes. 195*a28cd43dSSascha Wildner * Note: ZDICT_optimizeTrainFromBuffer_cover() requires about 8 bytes of memory for each input byte and additionally another 5 bytes of memory for each byte of memory for each thread. 196*a28cd43dSSascha Wildner */ 197*a28cd43dSSascha Wildner ZDICTLIB_API size_t ZDICT_optimizeTrainFromBuffer_cover( 198*a28cd43dSSascha Wildner void* dictBuffer, size_t dictBufferCapacity, 199*a28cd43dSSascha Wildner const void* samplesBuffer, const size_t* samplesSizes, unsigned nbSamples, 200*a28cd43dSSascha Wildner ZDICT_cover_params_t* parameters); 201*a28cd43dSSascha Wildner 202*a28cd43dSSascha Wildner /*! ZDICT_trainFromBuffer_fastCover(): 203*a28cd43dSSascha Wildner * Train a dictionary from an array of samples using a modified version of COVER algorithm. 204*a28cd43dSSascha Wildner * Samples must be stored concatenated in a single flat buffer `samplesBuffer`, 205*a28cd43dSSascha Wildner * supplied with an array of sizes `samplesSizes`, providing the size of each sample, in order. 206*a28cd43dSSascha Wildner * d and k are required. 207*a28cd43dSSascha Wildner * All other parameters are optional, will use default values if not provided 208*a28cd43dSSascha Wildner * The resulting dictionary will be saved into `dictBuffer`. 209*a28cd43dSSascha Wildner * @return: size of dictionary stored into `dictBuffer` (<= `dictBufferCapacity`) 210*a28cd43dSSascha Wildner * or an error code, which can be tested with ZDICT_isError(). 211*a28cd43dSSascha Wildner * See ZDICT_trainFromBuffer() for details on failure modes. 212*a28cd43dSSascha Wildner * Note: ZDICT_trainFromBuffer_fastCover() requires 6 * 2^f bytes of memory. 213*a28cd43dSSascha Wildner * Tips: In general, a reasonable dictionary has a size of ~ 100 KB. 214*a28cd43dSSascha Wildner * It's possible to select smaller or larger size, just by specifying `dictBufferCapacity`. 215*a28cd43dSSascha Wildner * In general, it's recommended to provide a few thousands samples, though this can vary a lot. 216*a28cd43dSSascha Wildner * It's recommended that total size of all samples be about ~x100 times the target size of dictionary. 217*a28cd43dSSascha Wildner */ 218*a28cd43dSSascha Wildner ZDICTLIB_API size_t ZDICT_trainFromBuffer_fastCover(void *dictBuffer, 219*a28cd43dSSascha Wildner size_t dictBufferCapacity, const void *samplesBuffer, 220*a28cd43dSSascha Wildner const size_t *samplesSizes, unsigned nbSamples, 221*a28cd43dSSascha Wildner ZDICT_fastCover_params_t parameters); 222*a28cd43dSSascha Wildner 223*a28cd43dSSascha Wildner /*! ZDICT_optimizeTrainFromBuffer_fastCover(): 224*a28cd43dSSascha Wildner * The same requirements as above hold for all the parameters except `parameters`. 225*a28cd43dSSascha Wildner * This function tries many parameter combinations (specifically, k and d combinations) 226*a28cd43dSSascha Wildner * and picks the best parameters. `*parameters` is filled with the best parameters found, 227*a28cd43dSSascha Wildner * dictionary constructed with those parameters is stored in `dictBuffer`. 228*a28cd43dSSascha Wildner * All of the parameters d, k, steps, f, and accel are optional. 229*a28cd43dSSascha Wildner * If d is non-zero then we don't check multiple values of d, otherwise we check d = {6, 8}. 230*a28cd43dSSascha Wildner * if steps is zero it defaults to its default value. 231*a28cd43dSSascha Wildner * If k is non-zero then we don't check multiple values of k, otherwise we check steps values in [50, 2000]. 232*a28cd43dSSascha Wildner * If f is zero, default value of 20 is used. 233*a28cd43dSSascha Wildner * If accel is zero, default value of 1 is used. 234*a28cd43dSSascha Wildner * 235*a28cd43dSSascha Wildner * @return: size of dictionary stored into `dictBuffer` (<= `dictBufferCapacity`) 236*a28cd43dSSascha Wildner * or an error code, which can be tested with ZDICT_isError(). 237*a28cd43dSSascha Wildner * On success `*parameters` contains the parameters selected. 238*a28cd43dSSascha Wildner * See ZDICT_trainFromBuffer() for details on failure modes. 239*a28cd43dSSascha Wildner * Note: ZDICT_optimizeTrainFromBuffer_fastCover() requires about 6 * 2^f bytes of memory for each thread. 240*a28cd43dSSascha Wildner */ 241*a28cd43dSSascha Wildner ZDICTLIB_API size_t ZDICT_optimizeTrainFromBuffer_fastCover(void* dictBuffer, 242*a28cd43dSSascha Wildner size_t dictBufferCapacity, const void* samplesBuffer, 243*a28cd43dSSascha Wildner const size_t* samplesSizes, unsigned nbSamples, 244*a28cd43dSSascha Wildner ZDICT_fastCover_params_t* parameters); 245*a28cd43dSSascha Wildner 246*a28cd43dSSascha Wildner typedef struct { 247*a28cd43dSSascha Wildner unsigned selectivityLevel; /* 0 means default; larger => select more => larger dictionary */ 248*a28cd43dSSascha Wildner ZDICT_params_t zParams; 249*a28cd43dSSascha Wildner } ZDICT_legacy_params_t; 250*a28cd43dSSascha Wildner 251*a28cd43dSSascha Wildner /*! ZDICT_trainFromBuffer_legacy(): 252*a28cd43dSSascha Wildner * Train a dictionary from an array of samples. 253*a28cd43dSSascha Wildner * Samples must be stored concatenated in a single flat buffer `samplesBuffer`, 254*a28cd43dSSascha Wildner * supplied with an array of sizes `samplesSizes`, providing the size of each sample, in order. 255*a28cd43dSSascha Wildner * The resulting dictionary will be saved into `dictBuffer`. 256*a28cd43dSSascha Wildner * `parameters` is optional and can be provided with values set to 0 to mean "default". 257*a28cd43dSSascha Wildner * @return: size of dictionary stored into `dictBuffer` (<= `dictBufferCapacity`) 258*a28cd43dSSascha Wildner * or an error code, which can be tested with ZDICT_isError(). 259*a28cd43dSSascha Wildner * See ZDICT_trainFromBuffer() for details on failure modes. 260*a28cd43dSSascha Wildner * Tips: In general, a reasonable dictionary has a size of ~ 100 KB. 261*a28cd43dSSascha Wildner * It's possible to select smaller or larger size, just by specifying `dictBufferCapacity`. 262*a28cd43dSSascha Wildner * In general, it's recommended to provide a few thousands samples, though this can vary a lot. 263*a28cd43dSSascha Wildner * It's recommended that total size of all samples be about ~x100 times the target size of dictionary. 264*a28cd43dSSascha Wildner * Note: ZDICT_trainFromBuffer_legacy() will send notifications into stderr if instructed to, using notificationLevel>0. 265*a28cd43dSSascha Wildner */ 266*a28cd43dSSascha Wildner ZDICTLIB_API size_t ZDICT_trainFromBuffer_legacy( 267*a28cd43dSSascha Wildner void *dictBuffer, size_t dictBufferCapacity, 268*a28cd43dSSascha Wildner const void *samplesBuffer, const size_t *samplesSizes, unsigned nbSamples, 269*a28cd43dSSascha Wildner ZDICT_legacy_params_t parameters); 270*a28cd43dSSascha Wildner 271*a28cd43dSSascha Wildner /* Deprecation warnings */ 272*a28cd43dSSascha Wildner /* It is generally possible to disable deprecation warnings from compiler, 273*a28cd43dSSascha Wildner for example with -Wno-deprecated-declarations for gcc 274*a28cd43dSSascha Wildner or _CRT_SECURE_NO_WARNINGS in Visual. 275*a28cd43dSSascha Wildner Otherwise, it's also possible to manually define ZDICT_DISABLE_DEPRECATE_WARNINGS */ 276*a28cd43dSSascha Wildner #ifdef ZDICT_DISABLE_DEPRECATE_WARNINGS 277*a28cd43dSSascha Wildner # define ZDICT_DEPRECATED(message) ZDICTLIB_API /* disable deprecation warnings */ 278*a28cd43dSSascha Wildner #else 279*a28cd43dSSascha Wildner # define ZDICT_GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__) 280*a28cd43dSSascha Wildner # if defined (__cplusplus) && (__cplusplus >= 201402) /* C++14 or greater */ 281*a28cd43dSSascha Wildner # define ZDICT_DEPRECATED(message) [[deprecated(message)]] ZDICTLIB_API 282*a28cd43dSSascha Wildner # elif defined(__clang__) || (ZDICT_GCC_VERSION >= 405) 283*a28cd43dSSascha Wildner # define ZDICT_DEPRECATED(message) ZDICTLIB_API __attribute__((deprecated(message))) 284*a28cd43dSSascha Wildner # elif (ZDICT_GCC_VERSION >= 301) 285*a28cd43dSSascha Wildner # define ZDICT_DEPRECATED(message) ZDICTLIB_API __attribute__((deprecated)) 286*a28cd43dSSascha Wildner # elif defined(_MSC_VER) 287*a28cd43dSSascha Wildner # define ZDICT_DEPRECATED(message) ZDICTLIB_API __declspec(deprecated(message)) 288*a28cd43dSSascha Wildner # else 289*a28cd43dSSascha Wildner # pragma message("WARNING: You need to implement ZDICT_DEPRECATED for this compiler") 290*a28cd43dSSascha Wildner # define ZDICT_DEPRECATED(message) ZDICTLIB_API 291*a28cd43dSSascha Wildner # endif 292*a28cd43dSSascha Wildner #endif /* ZDICT_DISABLE_DEPRECATE_WARNINGS */ 293*a28cd43dSSascha Wildner 294*a28cd43dSSascha Wildner ZDICT_DEPRECATED("use ZDICT_finalizeDictionary() instead") 295*a28cd43dSSascha Wildner size_t ZDICT_addEntropyTablesFromBuffer(void* dictBuffer, size_t dictContentSize, size_t dictBufferCapacity, 296*a28cd43dSSascha Wildner const void* samplesBuffer, const size_t* samplesSizes, unsigned nbSamples); 297*a28cd43dSSascha Wildner 298*a28cd43dSSascha Wildner 299*a28cd43dSSascha Wildner #endif /* ZDICT_STATIC_LINKING_ONLY */ 300*a28cd43dSSascha Wildner 301*a28cd43dSSascha Wildner #if defined (__cplusplus) 302*a28cd43dSSascha Wildner } 303*a28cd43dSSascha Wildner #endif 304*a28cd43dSSascha Wildner 305*a28cd43dSSascha Wildner #endif /* DICTBUILDER_H_001 */ 306