zstd (1.5.1)
1 /*
2 * Copyright (c) Yann Collet, Facebook, Inc.
3 * All rights reserved.
4 *
5 * This source code is licensed under both the BSD-style license (found in the
6 * LICENSE file in the root directory of this source tree) and the GPLv2 (found
7 * in the COPYING file in the root directory of this source tree).
8 * You may select, at your option, one of the above-listed licenses.
9 */
10
11 #ifndef DICTBUILDER_H_001
12 #define DICTBUILDER_H_001
13
14 #if defined (__cplusplus)
15 extern "C" {
16 #endif
17
18
19 /*====== Dependencies ======*/
20 #include <stddef.h> /* size_t */
21
22
23 /* ===== ZDICTLIB_API : control library symbols visibility ===== */
24 #ifndef ZDICTLIB_VISIBILITY
25 # if defined(__GNUC__) && (__GNUC__ >= 4)
26 # define ZDICTLIB_VISIBILITY __attribute__ ((visibility ("default")))
27 # else
28 # define ZDICTLIB_VISIBILITY
29 # endif
30 #endif
31 #if defined(ZSTD_DLL_EXPORT) && (ZSTD_DLL_EXPORT==1)
32 # define ZDICTLIB_API __declspec(dllexport) ZDICTLIB_VISIBILITY
33 #elif defined(ZSTD_DLL_IMPORT) && (ZSTD_DLL_IMPORT==1)
34 # 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 #else
36 # define ZDICTLIB_API ZDICTLIB_VISIBILITY
37 #endif
38
39 /*******************************************************************************
40 * Zstd dictionary builder
41 *
42 * FAQ
43 * ===
44 * Why should I use a dictionary?
45 * ------------------------------
46 *
47 * Zstd can use dictionaries to improve compression ratio of small data.
48 * Traditionally small files don't compress well because there is very little
49 * repetition in a single sample, since it is small. But, if you are compressing
50 * many similar files, like a bunch of JSON records that share the same
51 * structure, you can train a dictionary on ahead of time on some samples of
52 * these files. Then, zstd can use the dictionary to find repetitions that are
53 * present across samples. This can vastly improve compression ratio.
54 *
55 * When is a dictionary useful?
56 * ----------------------------
57 *
58 * Dictionaries are useful when compressing many small files that are similar.
59 * The larger a file is, the less benefit a dictionary will have. Generally,
60 * we don't expect dictionary compression to be effective past 100KB. And the
61 * smaller a file is, the more we would expect the dictionary to help.
62 *
63 * How do I use a dictionary?
64 * --------------------------
65 *
66 * Simply pass the dictionary to the zstd compressor with
67 * `ZSTD_CCtx_loadDictionary()`. The same dictionary must then be passed to
68 * the decompressor, using `ZSTD_DCtx_loadDictionary()`. There are other
69 * more advanced functions that allow selecting some options, see zstd.h for
70 * complete documentation.
71 *
72 * What is a zstd dictionary?
73 * --------------------------
74 *
75 * A zstd dictionary has two pieces: Its header, and its content. The header
76 * contains a magic number, the dictionary ID, and entropy tables. These
77 * entropy tables allow zstd to save on header costs in the compressed file,
78 * which really matters for small data. The content is just bytes, which are
79 * repeated content that is common across many samples.
80 *
81 * What is a raw content dictionary?
82 * ---------------------------------
83 *
84 * A raw content dictionary is just bytes. It doesn't have a zstd dictionary
85 * header, a dictionary ID, or entropy tables. Any buffer is a valid raw
86 * content dictionary.
87 *
88 * How do I train a dictionary?
89 * ----------------------------
90 *
91 * Gather samples from your use case. These samples should be similar to each
92 * other. If you have several use cases, you could try to train one dictionary
93 * per use case.
94 *
95 * Pass those samples to `ZDICT_trainFromBuffer()` and that will train your
96 * dictionary. There are a few advanced versions of this function, but this
97 * is a great starting point. If you want to further tune your dictionary
98 * you could try `ZDICT_optimizeTrainFromBuffer_cover()`. If that is too slow
99 * you can try `ZDICT_optimizeTrainFromBuffer_fastCover()`.
100 *
101 * If the dictionary training function fails, that is likely because you
102 * either passed too few samples, or a dictionary would not be effective
103 * for your data. Look at the messages that the dictionary trainer printed,
104 * if it doesn't say too few samples, then a dictionary would not be effective.
105 *
106 * How large should my dictionary be?
107 * ----------------------------------
108 *
109 * A reasonable dictionary size, the `dictBufferCapacity`, is about 100KB.
110 * The zstd CLI defaults to a 110KB dictionary. You likely don't need a
111 * dictionary larger than that. But, most use cases can get away with a
112 * smaller dictionary. The advanced dictionary builders can automatically
113 * shrink the dictionary for you, and select a the smallest size that
114 * doesn't hurt compression ratio too much. See the `shrinkDict` parameter.
115 * A smaller dictionary can save memory, and potentially speed up
116 * compression.
117 *
118 * How many samples should I provide to the dictionary builder?
119 * ------------------------------------------------------------
120 *
121 * We generally recommend passing ~100x the size of the dictionary
122 * in samples. A few thousand should suffice. Having too few samples
123 * can hurt the dictionaries effectiveness. Having more samples will
124 * only improve the dictionaries effectiveness. But having too many
125 * samples can slow down the dictionary builder.
126 *
127 * How do I determine if a dictionary will be effective?
128 * -----------------------------------------------------
129 *
130 * Simply train a dictionary and try it out. You can use zstd's built in
131 * benchmarking tool to test the dictionary effectiveness.
132 *
133 * # Benchmark levels 1-3 without a dictionary
134 * zstd -b1e3 -r /path/to/my/files
135 * # Benchmark levels 1-3 with a dictionary
136 * zstd -b1e3 -r /path/to/my/files -D /path/to/my/dictionary
137 *
138 * When should I retrain a dictionary?
139 * -----------------------------------
140 *
141 * You should retrain a dictionary when its effectiveness drops. Dictionary
142 * effectiveness drops as the data you are compressing changes. Generally, we do
143 * expect dictionaries to "decay" over time, as your data changes, but the rate
144 * at which they decay depends on your use case. Internally, we regularly
145 * retrain dictionaries, and if the new dictionary performs significantly
146 * better than the old dictionary, we will ship the new dictionary.
147 *
148 * I have a raw content dictionary, how do I turn it into a zstd dictionary?
149 * -------------------------------------------------------------------------
150 *
151 * If you have a raw content dictionary, e.g. by manually constructing it, or
152 * using a third-party dictionary builder, you can turn it into a zstd
153 * dictionary by using `ZDICT_finalizeDictionary()`. You'll also have to
154 * provide some samples of the data. It will add the zstd header to the
155 * raw content, which contains a dictionary ID and entropy tables, which
156 * will improve compression ratio, and allow zstd to write the dictionary ID
157 * into the frame, if you so choose.
158 *
159 * Do I have to use zstd's dictionary builder?
160 * -------------------------------------------
161 *
162 * No! You can construct dictionary content however you please, it is just
163 * bytes. It will always be valid as a raw content dictionary. If you want
164 * a zstd dictionary, which can improve compression ratio, use
165 * `ZDICT_finalizeDictionary()`.
166 *
167 * What is the attack surface of a zstd dictionary?
168 * ------------------------------------------------
169 *
170 * Zstd is heavily fuzz tested, including loading fuzzed dictionaries, so
171 * zstd should never crash, or access out-of-bounds memory no matter what
172 * the dictionary is. However, if an attacker can control the dictionary
173 * during decompression, they can cause zstd to generate arbitrary bytes,
174 * just like if they controlled the compressed data.
175 *
176 ******************************************************************************/
177
178
179 /*! ZDICT_trainFromBuffer():
180 * Train a dictionary from an array of samples.
181 * Redirect towards ZDICT_optimizeTrainFromBuffer_fastCover() single-threaded, with d=8, steps=4,
182 * f=20, and accel=1.
183 * Samples must be stored concatenated in a single flat buffer `samplesBuffer`,
184 * supplied with an array of sizes `samplesSizes`, providing the size of each sample, in order.
185 * The resulting dictionary will be saved into `dictBuffer`.
186 * @return: size of dictionary stored into `dictBuffer` (<= `dictBufferCapacity`)
187 * or an error code, which can be tested with ZDICT_isError().
188 * Note: Dictionary training will fail if there are not enough samples to construct a
189 * dictionary, or if most of the samples are too small (< 8 bytes being the lower limit).
190 * If dictionary training fails, you should use zstd without a dictionary, as the dictionary
191 * would've been ineffective anyways. If you believe your samples would benefit from a dictionary
192 * please open an issue with details, and we can look into it.
193 * Note: ZDICT_trainFromBuffer()'s memory usage is about 6 MB.
194 * Tips: In general, a reasonable dictionary has a size of ~ 100 KB.
195 * It's possible to select smaller or larger size, just by specifying `dictBufferCapacity`.
196 * In general, it's recommended to provide a few thousands samples, though this can vary a lot.
197 * It's recommended that total size of all samples be about ~x100 times the target size of dictionary.
198 */
199 ZDICTLIB_API size_t ZDICT_trainFromBuffer(void* dictBuffer, size_t dictBufferCapacity,
200 const void* samplesBuffer,
201 const size_t* samplesSizes, unsigned nbSamples);
202
203 typedef struct {
204 int compressionLevel; /*< optimize for a specific zstd compression level; 0 means default */
205 unsigned notificationLevel; /*< Write log to stderr; 0 = none (default); 1 = errors; 2 = progression; 3 = details; 4 = debug; */
206 unsigned dictID; /*< force dictID value; 0 means auto mode (32-bits random value)
207 * NOTE: The zstd format reserves some dictionary IDs for future use.
208 * You may use them in private settings, but be warned that they
209 * may be used by zstd in a public dictionary registry in the future.
210 * These dictionary IDs are:
211 * - low range : <= 32767
212 * - high range : >= (2^31)
213 */
214 } ZDICT_params_t;
215
216 /*! ZDICT_finalizeDictionary():
217 * Given a custom content as a basis for dictionary, and a set of samples,
218 * finalize dictionary by adding headers and statistics according to the zstd
219 * dictionary format.
220 *
221 * Samples must be stored concatenated in a flat buffer `samplesBuffer`,
222 * supplied with an array of sizes `samplesSizes`, providing the size of each
223 * sample in order. The samples are used to construct the statistics, so they
224 * should be representative of what you will compress with this dictionary.
225 *
226 * The compression level can be set in `parameters`. You should pass the
227 * compression level you expect to use in production. The statistics for each
228 * compression level differ, so tuning the dictionary for the compression level
229 * can help quite a bit.
230 *
231 * You can set an explicit dictionary ID in `parameters`, or allow us to pick
232 * a random dictionary ID for you, but we can't guarantee no collisions.
233 *
234 * The dstDictBuffer and the dictContent may overlap, and the content will be
235 * appended to the end of the header. If the header + the content doesn't fit in
236 * maxDictSize the beginning of the content is truncated to make room, since it
237 * is presumed that the most profitable content is at the end of the dictionary,
238 * since that is the cheapest to reference.
239 *
240 * `maxDictSize` must be >= max(dictContentSize, ZSTD_DICTSIZE_MIN).
241 *
242 * @return: size of dictionary stored into `dstDictBuffer` (<= `maxDictSize`),
243 * or an error code, which can be tested by ZDICT_isError().
244 * Note: ZDICT_finalizeDictionary() will push notifications into stderr if
245 * instructed to, using notificationLevel>0.
246 * NOTE: This function currently may fail in several edge cases including:
247 * * Not enough samples
248 * * Samples are uncompressible
249 * * Samples are all exactly the same
250 */
251 ZDICTLIB_API size_t ZDICT_finalizeDictionary(void* dstDictBuffer, size_t maxDictSize,
252 const void* dictContent, size_t dictContentSize,
253 const void* samplesBuffer, const size_t* samplesSizes, unsigned nbSamples,
254 ZDICT_params_t parameters);
255
256
257 /*====== Helper functions ======*/
258 ZDICTLIB_API unsigned ZDICT_getDictID(const void* dictBuffer, size_t dictSize); /**< extracts dictID; @return zero if error (not a valid dictionary) */
259 ZDICTLIB_API size_t ZDICT_getDictHeaderSize(const void* dictBuffer, size_t dictSize); /* returns dict header size; returns a ZSTD error code on failure */
260 ZDICTLIB_API unsigned ZDICT_isError(size_t errorCode);
261 ZDICTLIB_API const char* ZDICT_getErrorName(size_t errorCode);
262
263
264
265 #ifdef ZDICT_STATIC_LINKING_ONLY
266
267 /* ====================================================================================
268 * The definitions in this section are considered experimental.
269 * They should never be used with a dynamic library, as they may change in the future.
270 * They are provided for advanced usages.
271 * Use them only in association with static linking.
272 * ==================================================================================== */
273
274 #define ZDICT_DICTSIZE_MIN 256
275 /* Deprecated: Remove in v1.6.0 */
276 #define ZDICT_CONTENTSIZE_MIN 128
277
278 /*! ZDICT_cover_params_t:
279 * k and d are the only required parameters.
280 * For others, value 0 means default.
281 */
282 typedef struct {
283 unsigned k; /* Segment size : constraint: 0 < k : Reasonable range [16, 2048+] */
284 unsigned d; /* dmer size : constraint: 0 < d <= k : Reasonable range [6, 16] */
285 unsigned steps; /* Number of steps : Only used for optimization : 0 means default (40) : Higher means more parameters checked */
286 unsigned nbThreads; /* Number of threads : constraint: 0 < nbThreads : 1 means single-threaded : Only used for optimization : Ignored if ZSTD_MULTITHREAD is not defined */
287 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 */
288 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 */
289 unsigned shrinkDictMaxRegression; /* Sets shrinkDictMaxRegression so that a smaller dictionary can be at worse shrinkDictMaxRegression% worse than the max dict size dictionary. */
290 ZDICT_params_t zParams;
291 } ZDICT_cover_params_t;
292
293 typedef struct {
294 unsigned k; /* Segment size : constraint: 0 < k : Reasonable range [16, 2048+] */
295 unsigned d; /* dmer size : constraint: 0 < d <= k : Reasonable range [6, 16] */
296 unsigned f; /* log of size of frequency array : constraint: 0 < f <= 31 : 1 means default(20)*/
297 unsigned steps; /* Number of steps : Only used for optimization : 0 means default (40) : Higher means more parameters checked */
298 unsigned nbThreads; /* Number of threads : constraint: 0 < nbThreads : 1 means single-threaded : Only used for optimization : Ignored if ZSTD_MULTITHREAD is not defined */
299 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 */
300 unsigned accel; /* Acceleration level: constraint: 0 < accel <= 10, higher means faster and less accurate, 0 means default(1) */
301 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 */
302 unsigned shrinkDictMaxRegression; /* Sets shrinkDictMaxRegression so that a smaller dictionary can be at worse shrinkDictMaxRegression% worse than the max dict size dictionary. */
303
304 ZDICT_params_t zParams;
305 } ZDICT_fastCover_params_t;
306
307 /*! ZDICT_trainFromBuffer_cover():
308 * Train a dictionary from an array of samples using the COVER algorithm.
309 * Samples must be stored concatenated in a single flat buffer `samplesBuffer`,
310 * supplied with an array of sizes `samplesSizes`, providing the size of each sample, in order.
311 * The resulting dictionary will be saved into `dictBuffer`.
312 * @return: size of dictionary stored into `dictBuffer` (<= `dictBufferCapacity`)
313 * or an error code, which can be tested with ZDICT_isError().
314 * See ZDICT_trainFromBuffer() for details on failure modes.
315 * Note: ZDICT_trainFromBuffer_cover() requires about 9 bytes of memory for each input byte.
316 * Tips: In general, a reasonable dictionary has a size of ~ 100 KB.
317 * It's possible to select smaller or larger size, just by specifying `dictBufferCapacity`.
318 * In general, it's recommended to provide a few thousands samples, though this can vary a lot.
319 * It's recommended that total size of all samples be about ~x100 times the target size of dictionary.
320 */
321 ZDICTLIB_API size_t ZDICT_trainFromBuffer_cover(
322 void *dictBuffer, size_t dictBufferCapacity,
323 const void *samplesBuffer, const size_t *samplesSizes, unsigned nbSamples,
324 ZDICT_cover_params_t parameters);
325
326 /*! ZDICT_optimizeTrainFromBuffer_cover():
327 * The same requirements as above hold for all the parameters except `parameters`.
328 * This function tries many parameter combinations and picks the best parameters.
329 * `*parameters` is filled with the best parameters found,
330 * dictionary constructed with those parameters is stored in `dictBuffer`.
331 *
332 * All of the parameters d, k, steps are optional.
333 * If d is non-zero then we don't check multiple values of d, otherwise we check d = {6, 8}.
334 * if steps is zero it defaults to its default value.
335 * If k is non-zero then we don't check multiple values of k, otherwise we check steps values in [50, 2000].
336 *
337 * @return: size of dictionary stored into `dictBuffer` (<= `dictBufferCapacity`)
338 * or an error code, which can be tested with ZDICT_isError().
339 * On success `*parameters` contains the parameters selected.
340 * See ZDICT_trainFromBuffer() for details on failure modes.
341 * 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.
342 */
343 ZDICTLIB_API size_t ZDICT_optimizeTrainFromBuffer_cover(
344 void* dictBuffer, size_t dictBufferCapacity,
345 const void* samplesBuffer, const size_t* samplesSizes, unsigned nbSamples,
346 ZDICT_cover_params_t* parameters);
347
348 /*! ZDICT_trainFromBuffer_fastCover():
349 * Train a dictionary from an array of samples using a modified version of COVER algorithm.
350 * Samples must be stored concatenated in a single flat buffer `samplesBuffer`,
351 * supplied with an array of sizes `samplesSizes`, providing the size of each sample, in order.
352 * d and k are required.
353 * All other parameters are optional, will use default values if not provided
354 * The resulting dictionary will be saved into `dictBuffer`.
355 * @return: size of dictionary stored into `dictBuffer` (<= `dictBufferCapacity`)
356 * or an error code, which can be tested with ZDICT_isError().
357 * See ZDICT_trainFromBuffer() for details on failure modes.
358 * Note: ZDICT_trainFromBuffer_fastCover() requires 6 * 2^f bytes of memory.
359 * Tips: In general, a reasonable dictionary has a size of ~ 100 KB.
360 * It's possible to select smaller or larger size, just by specifying `dictBufferCapacity`.
361 * In general, it's recommended to provide a few thousands samples, though this can vary a lot.
362 * It's recommended that total size of all samples be about ~x100 times the target size of dictionary.
363 */
364 ZDICTLIB_API size_t ZDICT_trainFromBuffer_fastCover(void *dictBuffer,
365 size_t dictBufferCapacity, const void *samplesBuffer,
366 const size_t *samplesSizes, unsigned nbSamples,
367 ZDICT_fastCover_params_t parameters);
368
369 /*! ZDICT_optimizeTrainFromBuffer_fastCover():
370 * The same requirements as above hold for all the parameters except `parameters`.
371 * This function tries many parameter combinations (specifically, k and d combinations)
372 * and picks the best parameters. `*parameters` is filled with the best parameters found,
373 * dictionary constructed with those parameters is stored in `dictBuffer`.
374 * All of the parameters d, k, steps, f, and accel are optional.
375 * If d is non-zero then we don't check multiple values of d, otherwise we check d = {6, 8}.
376 * if steps is zero it defaults to its default value.
377 * If k is non-zero then we don't check multiple values of k, otherwise we check steps values in [50, 2000].
378 * If f is zero, default value of 20 is used.
379 * If accel is zero, default value of 1 is used.
380 *
381 * @return: size of dictionary stored into `dictBuffer` (<= `dictBufferCapacity`)
382 * or an error code, which can be tested with ZDICT_isError().
383 * On success `*parameters` contains the parameters selected.
384 * See ZDICT_trainFromBuffer() for details on failure modes.
385 * Note: ZDICT_optimizeTrainFromBuffer_fastCover() requires about 6 * 2^f bytes of memory for each thread.
386 */
387 ZDICTLIB_API size_t ZDICT_optimizeTrainFromBuffer_fastCover(void* dictBuffer,
388 size_t dictBufferCapacity, const void* samplesBuffer,
389 const size_t* samplesSizes, unsigned nbSamples,
390 ZDICT_fastCover_params_t* parameters);
391
392 typedef struct {
393 unsigned selectivityLevel; /* 0 means default; larger => select more => larger dictionary */
394 ZDICT_params_t zParams;
395 } ZDICT_legacy_params_t;
396
397 /*! ZDICT_trainFromBuffer_legacy():
398 * Train a dictionary from an array of samples.
399 * Samples must be stored concatenated in a single flat buffer `samplesBuffer`,
400 * supplied with an array of sizes `samplesSizes`, providing the size of each sample, in order.
401 * The resulting dictionary will be saved into `dictBuffer`.
402 * `parameters` is optional and can be provided with values set to 0 to mean "default".
403 * @return: size of dictionary stored into `dictBuffer` (<= `dictBufferCapacity`)
404 * or an error code, which can be tested with ZDICT_isError().
405 * See ZDICT_trainFromBuffer() for details on failure modes.
406 * Tips: In general, a reasonable dictionary has a size of ~ 100 KB.
407 * It's possible to select smaller or larger size, just by specifying `dictBufferCapacity`.
408 * In general, it's recommended to provide a few thousands samples, though this can vary a lot.
409 * It's recommended that total size of all samples be about ~x100 times the target size of dictionary.
410 * Note: ZDICT_trainFromBuffer_legacy() will send notifications into stderr if instructed to, using notificationLevel>0.
411 */
412 ZDICTLIB_API size_t ZDICT_trainFromBuffer_legacy(
413 void* dictBuffer, size_t dictBufferCapacity,
414 const void* samplesBuffer, const size_t* samplesSizes, unsigned nbSamples,
415 ZDICT_legacy_params_t parameters);
416
417
418 /* Deprecation warnings */
419 /* It is generally possible to disable deprecation warnings from compiler,
420 for example with -Wno-deprecated-declarations for gcc
421 or _CRT_SECURE_NO_WARNINGS in Visual.
422 Otherwise, it's also possible to manually define ZDICT_DISABLE_DEPRECATE_WARNINGS */
423 #ifdef ZDICT_DISABLE_DEPRECATE_WARNINGS
424 # define ZDICT_DEPRECATED(message) ZDICTLIB_API /* disable deprecation warnings */
425 #else
426 # define ZDICT_GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__)
427 # if defined (__cplusplus) && (__cplusplus >= 201402) /* C++14 or greater */
428 # define ZDICT_DEPRECATED(message) [[deprecated(message)]] ZDICTLIB_API
429 # elif defined(__clang__) || (ZDICT_GCC_VERSION >= 405)
430 # define ZDICT_DEPRECATED(message) ZDICTLIB_API __attribute__((deprecated(message)))
431 # elif (ZDICT_GCC_VERSION >= 301)
432 # define ZDICT_DEPRECATED(message) ZDICTLIB_API __attribute__((deprecated))
433 # elif defined(_MSC_VER)
434 # define ZDICT_DEPRECATED(message) ZDICTLIB_API __declspec(deprecated(message))
435 # else
436 # pragma message("WARNING: You need to implement ZDICT_DEPRECATED for this compiler")
437 # define ZDICT_DEPRECATED(message) ZDICTLIB_API
438 # endif
439 #endif /* ZDICT_DISABLE_DEPRECATE_WARNINGS */
440
441 ZDICT_DEPRECATED("use ZDICT_finalizeDictionary() instead")
442 size_t ZDICT_addEntropyTablesFromBuffer(void* dictBuffer, size_t dictContentSize, size_t dictBufferCapacity,
443 const void* samplesBuffer, const size_t* samplesSizes, unsigned nbSamples);
444
445
446 #endif /* ZDICT_STATIC_LINKING_ONLY */
447
448 #if defined (__cplusplus)
449 }
450 #endif
451
452 #endif /* DICTBUILDER_H_001 */
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