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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-21 11:54:28 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-21 11:54:28 +0000
commite6918187568dbd01842d8d1d2c808ce16a894239 (patch)
tree64f88b554b444a49f656b6c656111a145cbbaa28 /src/zstd/lib/dictBuilder/zdict.h
parentInitial commit. (diff)
downloadceph-e6918187568dbd01842d8d1d2c808ce16a894239.tar.xz
ceph-e6918187568dbd01842d8d1d2c808ce16a894239.zip
Adding upstream version 18.2.2.upstream/18.2.2
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
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diff --git a/src/zstd/lib/dictBuilder/zdict.h b/src/zstd/lib/dictBuilder/zdict.h
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+/*
+ * Copyright (c) 2016-2020, Yann Collet, Facebook, Inc.
+ * 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.
+ */
+
+#ifndef DICTBUILDER_H_001
+#define DICTBUILDER_H_001
+
+#if defined (__cplusplus)
+extern "C" {
+#endif
+
+
+/*====== Dependencies ======*/
+#include <stddef.h> /* size_t */
+
+
+/* ===== ZDICTLIB_API : control library symbols visibility ===== */
+#ifndef ZDICTLIB_VISIBILITY
+# if defined(__GNUC__) && (__GNUC__ >= 4)
+# define ZDICTLIB_VISIBILITY __attribute__ ((visibility ("default")))
+# else
+# define ZDICTLIB_VISIBILITY
+# endif
+#endif
+#if defined(ZSTD_DLL_EXPORT) && (ZSTD_DLL_EXPORT==1)
+# define ZDICTLIB_API __declspec(dllexport) ZDICTLIB_VISIBILITY
+#elif defined(ZSTD_DLL_IMPORT) && (ZSTD_DLL_IMPORT==1)
+# 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.*/
+#else
+# define ZDICTLIB_API ZDICTLIB_VISIBILITY
+#endif
+
+
+/*! ZDICT_trainFromBuffer():
+ * Train a dictionary from an array of samples.
+ * Redirect towards ZDICT_optimizeTrainFromBuffer_fastCover() single-threaded, with d=8, steps=4,
+ * f=20, and accel=1.
+ * Samples must be stored concatenated in a single flat buffer `samplesBuffer`,
+ * supplied with an array of sizes `samplesSizes`, providing the size of each sample, in order.
+ * The resulting dictionary will be saved into `dictBuffer`.
+ * @return: size of dictionary stored into `dictBuffer` (<= `dictBufferCapacity`)
+ * or an error code, which can be tested with ZDICT_isError().
+ * Note: Dictionary training will fail if there are not enough samples to construct a
+ * dictionary, or if most of the samples are too small (< 8 bytes being the lower limit).
+ * If dictionary training fails, you should use zstd without a dictionary, as the dictionary
+ * would've been ineffective anyways. If you believe your samples would benefit from a dictionary
+ * please open an issue with details, and we can look into it.
+ * Note: ZDICT_trainFromBuffer()'s memory usage is about 6 MB.
+ * Tips: In general, a reasonable dictionary has a size of ~ 100 KB.
+ * It's possible to select smaller or larger size, just by specifying `dictBufferCapacity`.
+ * In general, it's recommended to provide a few thousands samples, though this can vary a lot.
+ * It's recommended that total size of all samples be about ~x100 times the target size of dictionary.
+ */
+ZDICTLIB_API size_t ZDICT_trainFromBuffer(void* dictBuffer, size_t dictBufferCapacity,
+ const void* samplesBuffer,
+ const size_t* samplesSizes, unsigned nbSamples);
+
+typedef struct {
+ int compressionLevel; /*< optimize for a specific zstd compression level; 0 means default */
+ unsigned notificationLevel; /*< Write log to stderr; 0 = none (default); 1 = errors; 2 = progression; 3 = details; 4 = debug; */
+ unsigned dictID; /*< force dictID value; 0 means auto mode (32-bits random value) */
+} ZDICT_params_t;
+
+/*! ZDICT_finalizeDictionary():
+ * Given a custom content as a basis for dictionary, and a set of samples,
+ * finalize dictionary by adding headers and statistics according to the zstd
+ * dictionary format.
+ *
+ * Samples must be stored concatenated in a flat buffer `samplesBuffer`,
+ * supplied with an array of sizes `samplesSizes`, providing the size of each
+ * sample in order. The samples are used to construct the statistics, so they
+ * should be representative of what you will compress with this dictionary.
+ *
+ * The compression level can be set in `parameters`. You should pass the
+ * compression level you expect to use in production. The statistics for each
+ * compression level differ, so tuning the dictionary for the compression level
+ * can help quite a bit.
+ *
+ * You can set an explicit dictionary ID in `parameters`, or allow us to pick
+ * a random dictionary ID for you, but we can't guarantee no collisions.
+ *
+ * The dstDictBuffer and the dictContent may overlap, and the content will be
+ * appended to the end of the header. If the header + the content doesn't fit in
+ * maxDictSize the beginning of the content is truncated to make room, since it
+ * is presumed that the most profitable content is at the end of the dictionary,
+ * since that is the cheapest to reference.
+ *
+ * `dictContentSize` must be >= ZDICT_CONTENTSIZE_MIN bytes.
+ * `maxDictSize` must be >= max(dictContentSize, ZSTD_DICTSIZE_MIN).
+ *
+ * @return: size of dictionary stored into `dstDictBuffer` (<= `maxDictSize`),
+ * or an error code, which can be tested by ZDICT_isError().
+ * Note: ZDICT_finalizeDictionary() will push notifications into stderr if
+ * instructed to, using notificationLevel>0.
+ * NOTE: This function currently may fail in several edge cases including:
+ * * Not enough samples
+ * * Samples are uncompressible
+ * * Samples are all exactly the same
+ */
+ZDICTLIB_API size_t ZDICT_finalizeDictionary(void* dstDictBuffer, size_t maxDictSize,
+ const void* dictContent, size_t dictContentSize,
+ const void* samplesBuffer, const size_t* samplesSizes, unsigned nbSamples,
+ ZDICT_params_t parameters);
+
+
+/*====== Helper functions ======*/
+ZDICTLIB_API unsigned ZDICT_getDictID(const void* dictBuffer, size_t dictSize); /**< extracts dictID; @return zero if error (not a valid dictionary) */
+ZDICTLIB_API size_t ZDICT_getDictHeaderSize(const void* dictBuffer, size_t dictSize); /* returns dict header size; returns a ZSTD error code on failure */
+ZDICTLIB_API unsigned ZDICT_isError(size_t errorCode);
+ZDICTLIB_API const char* ZDICT_getErrorName(size_t errorCode);
+
+
+
+#ifdef ZDICT_STATIC_LINKING_ONLY
+
+/* ====================================================================================
+ * The definitions in this section are considered experimental.
+ * They should never be used with a dynamic library, as they may change in the future.
+ * They are provided for advanced usages.
+ * Use them only in association with static linking.
+ * ==================================================================================== */
+
+#define ZDICT_CONTENTSIZE_MIN 128
+#define ZDICT_DICTSIZE_MIN 256
+
+/*! ZDICT_cover_params_t:
+ * k and d are the only required parameters.
+ * For others, value 0 means default.
+ */
+typedef struct {
+ unsigned k; /* Segment size : constraint: 0 < k : Reasonable range [16, 2048+] */
+ unsigned d; /* dmer size : constraint: 0 < d <= k : Reasonable range [6, 16] */
+ unsigned steps; /* Number of steps : Only used for optimization : 0 means default (40) : Higher means more parameters checked */
+ unsigned nbThreads; /* Number of threads : constraint: 0 < nbThreads : 1 means single-threaded : Only used for optimization : Ignored if ZSTD_MULTITHREAD is not defined */
+ 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 */
+ 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 */
+ unsigned shrinkDictMaxRegression; /* Sets shrinkDictMaxRegression so that a smaller dictionary can be at worse shrinkDictMaxRegression% worse than the max dict size dictionary. */
+ ZDICT_params_t zParams;
+} ZDICT_cover_params_t;
+
+typedef struct {
+ unsigned k; /* Segment size : constraint: 0 < k : Reasonable range [16, 2048+] */
+ unsigned d; /* dmer size : constraint: 0 < d <= k : Reasonable range [6, 16] */
+ unsigned f; /* log of size of frequency array : constraint: 0 < f <= 31 : 1 means default(20)*/
+ unsigned steps; /* Number of steps : Only used for optimization : 0 means default (40) : Higher means more parameters checked */
+ unsigned nbThreads; /* Number of threads : constraint: 0 < nbThreads : 1 means single-threaded : Only used for optimization : Ignored if ZSTD_MULTITHREAD is not defined */
+ 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 */
+ unsigned accel; /* Acceleration level: constraint: 0 < accel <= 10, higher means faster and less accurate, 0 means default(1) */
+ 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 */
+ unsigned shrinkDictMaxRegression; /* Sets shrinkDictMaxRegression so that a smaller dictionary can be at worse shrinkDictMaxRegression% worse than the max dict size dictionary. */
+
+ ZDICT_params_t zParams;
+} ZDICT_fastCover_params_t;
+
+/*! ZDICT_trainFromBuffer_cover():
+ * Train a dictionary from an array of samples using the COVER algorithm.
+ * Samples must be stored concatenated in a single flat buffer `samplesBuffer`,
+ * supplied with an array of sizes `samplesSizes`, providing the size of each sample, in order.
+ * The resulting dictionary will be saved into `dictBuffer`.
+ * @return: size of dictionary stored into `dictBuffer` (<= `dictBufferCapacity`)
+ * or an error code, which can be tested with ZDICT_isError().
+ * See ZDICT_trainFromBuffer() for details on failure modes.
+ * Note: ZDICT_trainFromBuffer_cover() requires about 9 bytes of memory for each input byte.
+ * Tips: In general, a reasonable dictionary has a size of ~ 100 KB.
+ * It's possible to select smaller or larger size, just by specifying `dictBufferCapacity`.
+ * In general, it's recommended to provide a few thousands samples, though this can vary a lot.
+ * It's recommended that total size of all samples be about ~x100 times the target size of dictionary.
+ */
+ZDICTLIB_API size_t ZDICT_trainFromBuffer_cover(
+ void *dictBuffer, size_t dictBufferCapacity,
+ const void *samplesBuffer, const size_t *samplesSizes, unsigned nbSamples,
+ ZDICT_cover_params_t parameters);
+
+/*! ZDICT_optimizeTrainFromBuffer_cover():
+ * The same requirements as above hold for all the parameters except `parameters`.
+ * This function tries many parameter combinations and picks the best parameters.
+ * `*parameters` is filled with the best parameters found,
+ * dictionary constructed with those parameters is stored in `dictBuffer`.
+ *
+ * All of the parameters d, k, steps are optional.
+ * If d is non-zero then we don't check multiple values of d, otherwise we check d = {6, 8}.
+ * if steps is zero it defaults to its default value.
+ * If k is non-zero then we don't check multiple values of k, otherwise we check steps values in [50, 2000].
+ *
+ * @return: size of dictionary stored into `dictBuffer` (<= `dictBufferCapacity`)
+ * or an error code, which can be tested with ZDICT_isError().
+ * On success `*parameters` contains the parameters selected.
+ * See ZDICT_trainFromBuffer() for details on failure modes.
+ * 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.
+ */
+ZDICTLIB_API size_t ZDICT_optimizeTrainFromBuffer_cover(
+ void* dictBuffer, size_t dictBufferCapacity,
+ const void* samplesBuffer, const size_t* samplesSizes, unsigned nbSamples,
+ ZDICT_cover_params_t* parameters);
+
+/*! ZDICT_trainFromBuffer_fastCover():
+ * Train a dictionary from an array of samples using a modified version of COVER algorithm.
+ * Samples must be stored concatenated in a single flat buffer `samplesBuffer`,
+ * supplied with an array of sizes `samplesSizes`, providing the size of each sample, in order.
+ * d and k are required.
+ * All other parameters are optional, will use default values if not provided
+ * The resulting dictionary will be saved into `dictBuffer`.
+ * @return: size of dictionary stored into `dictBuffer` (<= `dictBufferCapacity`)
+ * or an error code, which can be tested with ZDICT_isError().
+ * See ZDICT_trainFromBuffer() for details on failure modes.
+ * Note: ZDICT_trainFromBuffer_fastCover() requires 6 * 2^f bytes of memory.
+ * Tips: In general, a reasonable dictionary has a size of ~ 100 KB.
+ * It's possible to select smaller or larger size, just by specifying `dictBufferCapacity`.
+ * In general, it's recommended to provide a few thousands samples, though this can vary a lot.
+ * It's recommended that total size of all samples be about ~x100 times the target size of dictionary.
+ */
+ZDICTLIB_API size_t ZDICT_trainFromBuffer_fastCover(void *dictBuffer,
+ size_t dictBufferCapacity, const void *samplesBuffer,
+ const size_t *samplesSizes, unsigned nbSamples,
+ ZDICT_fastCover_params_t parameters);
+
+/*! ZDICT_optimizeTrainFromBuffer_fastCover():
+ * The same requirements as above hold for all the parameters except `parameters`.
+ * This function tries many parameter combinations (specifically, k and d combinations)
+ * and picks the best parameters. `*parameters` is filled with the best parameters found,
+ * dictionary constructed with those parameters is stored in `dictBuffer`.
+ * All of the parameters d, k, steps, f, and accel are optional.
+ * If d is non-zero then we don't check multiple values of d, otherwise we check d = {6, 8}.
+ * if steps is zero it defaults to its default value.
+ * If k is non-zero then we don't check multiple values of k, otherwise we check steps values in [50, 2000].
+ * If f is zero, default value of 20 is used.
+ * If accel is zero, default value of 1 is used.
+ *
+ * @return: size of dictionary stored into `dictBuffer` (<= `dictBufferCapacity`)
+ * or an error code, which can be tested with ZDICT_isError().
+ * On success `*parameters` contains the parameters selected.
+ * See ZDICT_trainFromBuffer() for details on failure modes.
+ * Note: ZDICT_optimizeTrainFromBuffer_fastCover() requires about 6 * 2^f bytes of memory for each thread.
+ */
+ZDICTLIB_API size_t ZDICT_optimizeTrainFromBuffer_fastCover(void* dictBuffer,
+ size_t dictBufferCapacity, const void* samplesBuffer,
+ const size_t* samplesSizes, unsigned nbSamples,
+ ZDICT_fastCover_params_t* parameters);
+
+typedef struct {
+ unsigned selectivityLevel; /* 0 means default; larger => select more => larger dictionary */
+ ZDICT_params_t zParams;
+} ZDICT_legacy_params_t;
+
+/*! ZDICT_trainFromBuffer_legacy():
+ * Train a dictionary from an array of samples.
+ * Samples must be stored concatenated in a single flat buffer `samplesBuffer`,
+ * supplied with an array of sizes `samplesSizes`, providing the size of each sample, in order.
+ * The resulting dictionary will be saved into `dictBuffer`.
+ * `parameters` is optional and can be provided with values set to 0 to mean "default".
+ * @return: size of dictionary stored into `dictBuffer` (<= `dictBufferCapacity`)
+ * or an error code, which can be tested with ZDICT_isError().
+ * See ZDICT_trainFromBuffer() for details on failure modes.
+ * Tips: In general, a reasonable dictionary has a size of ~ 100 KB.
+ * It's possible to select smaller or larger size, just by specifying `dictBufferCapacity`.
+ * In general, it's recommended to provide a few thousands samples, though this can vary a lot.
+ * It's recommended that total size of all samples be about ~x100 times the target size of dictionary.
+ * Note: ZDICT_trainFromBuffer_legacy() will send notifications into stderr if instructed to, using notificationLevel>0.
+ */
+ZDICTLIB_API size_t ZDICT_trainFromBuffer_legacy(
+ void *dictBuffer, size_t dictBufferCapacity,
+ const void *samplesBuffer, const size_t *samplesSizes, unsigned nbSamples,
+ ZDICT_legacy_params_t parameters);
+
+/* Deprecation warnings */
+/* It is generally possible to disable deprecation warnings from compiler,
+ for example with -Wno-deprecated-declarations for gcc
+ or _CRT_SECURE_NO_WARNINGS in Visual.
+ Otherwise, it's also possible to manually define ZDICT_DISABLE_DEPRECATE_WARNINGS */
+#ifdef ZDICT_DISABLE_DEPRECATE_WARNINGS
+# define ZDICT_DEPRECATED(message) ZDICTLIB_API /* disable deprecation warnings */
+#else
+# define ZDICT_GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__)
+# if defined (__cplusplus) && (__cplusplus >= 201402) /* C++14 or greater */
+# define ZDICT_DEPRECATED(message) [[deprecated(message)]] ZDICTLIB_API
+# elif (ZDICT_GCC_VERSION >= 405) || defined(__clang__)
+# define ZDICT_DEPRECATED(message) ZDICTLIB_API __attribute__((deprecated(message)))
+# elif (ZDICT_GCC_VERSION >= 301)
+# define ZDICT_DEPRECATED(message) ZDICTLIB_API __attribute__((deprecated))
+# elif defined(_MSC_VER)
+# define ZDICT_DEPRECATED(message) ZDICTLIB_API __declspec(deprecated(message))
+# else
+# pragma message("WARNING: You need to implement ZDICT_DEPRECATED for this compiler")
+# define ZDICT_DEPRECATED(message) ZDICTLIB_API
+# endif
+#endif /* ZDICT_DISABLE_DEPRECATE_WARNINGS */
+
+ZDICT_DEPRECATED("use ZDICT_finalizeDictionary() instead")
+size_t ZDICT_addEntropyTablesFromBuffer(void* dictBuffer, size_t dictContentSize, size_t dictBufferCapacity,
+ const void* samplesBuffer, const size_t* samplesSizes, unsigned nbSamples);
+
+
+#endif /* ZDICT_STATIC_LINKING_ONLY */
+
+#if defined (__cplusplus)
+}
+#endif
+
+#endif /* DICTBUILDER_H_001 */