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1/* ******************************************************************
2 * huff0 huffman codec,
3 * part of Finite State Entropy library
4 * Copyright (c) Yann Collet, Facebook, Inc.
5 *
6 * You can contact the author at :
7 * - Source repository : https://github.com/Cyan4973/FiniteStateEntropy
8 *
9 * This source code is licensed under both the BSD-style license (found in the
10 * LICENSE file in the root directory of this source tree) and the GPLv2 (found
11 * in the COPYING file in the root directory of this source tree).
12 * You may select, at your option, one of the above-listed licenses.
13****************************************************************** */
14
15
16#ifndef HUF_H_298734234
17#define HUF_H_298734234
18
19/* *** Dependencies *** */
20#include "zstd_deps.h" /* size_t */
21
22
23/* *** library symbols visibility *** */
24/* Note : when linking with -fvisibility=hidden on gcc, or by default on Visual,
25 * HUF symbols remain "private" (internal symbols for library only).
26 * Set macro FSE_DLL_EXPORT to 1 if you want HUF symbols visible on DLL interface */
27#if defined(FSE_DLL_EXPORT) && (FSE_DLL_EXPORT==1) && defined(__GNUC__) && (__GNUC__ >= 4)
28# define HUF_PUBLIC_API __attribute__ ((visibility ("default")))
29#elif defined(FSE_DLL_EXPORT) && (FSE_DLL_EXPORT==1) /* Visual expected */
30# define HUF_PUBLIC_API __declspec(dllexport)
31#elif defined(FSE_DLL_IMPORT) && (FSE_DLL_IMPORT==1)
32# define HUF_PUBLIC_API __declspec(dllimport) /* not required, just to generate faster code (saves a function pointer load from IAT and an indirect jump) */
33#else
34# define HUF_PUBLIC_API
35#endif
36
37
38/* ========================== */
39/* *** simple functions *** */
40/* ========================== */
41
42/* HUF_compress() :
43 * Compress content from buffer 'src', of size 'srcSize', into buffer 'dst'.
44 * 'dst' buffer must be already allocated.
45 * Compression runs faster if `dstCapacity` >= HUF_compressBound(srcSize).
46 * `srcSize` must be <= `HUF_BLOCKSIZE_MAX` == 128 KB.
47 * @return : size of compressed data (<= `dstCapacity`).
48 * Special values : if return == 0, srcData is not compressible => Nothing is stored within dst !!!
49 * if HUF_isError(return), compression failed (more details using HUF_getErrorName())
50 */
51HUF_PUBLIC_API size_t HUF_compress(void* dst, size_t dstCapacity,
52 const void* src, size_t srcSize);
53
54/* HUF_decompress() :
55 * Decompress HUF data from buffer 'cSrc', of size 'cSrcSize',
56 * into already allocated buffer 'dst', of minimum size 'dstSize'.
57 * `originalSize` : **must** be the ***exact*** size of original (uncompressed) data.
58 * Note : in contrast with FSE, HUF_decompress can regenerate
59 * RLE (cSrcSize==1) and uncompressed (cSrcSize==dstSize) data,
60 * because it knows size to regenerate (originalSize).
61 * @return : size of regenerated data (== originalSize),
62 * or an error code, which can be tested using HUF_isError()
63 */
64HUF_PUBLIC_API size_t HUF_decompress(void* dst, size_t originalSize,
65 const void* cSrc, size_t cSrcSize);
66
67
68/* *** Tool functions *** */
69#define HUF_BLOCKSIZE_MAX (128 * 1024) /*< maximum input size for a single block compressed with HUF_compress */
70HUF_PUBLIC_API size_t HUF_compressBound(size_t size); /*< maximum compressed size (worst case) */
71
72/* Error Management */
73HUF_PUBLIC_API unsigned HUF_isError(size_t code); /*< tells if a return value is an error code */
74HUF_PUBLIC_API const char* HUF_getErrorName(size_t code); /*< provides error code string (useful for debugging) */
75
76
77/* *** Advanced function *** */
78
79/* HUF_compress2() :
80 * Same as HUF_compress(), but offers control over `maxSymbolValue` and `tableLog`.
81 * `maxSymbolValue` must be <= HUF_SYMBOLVALUE_MAX .
82 * `tableLog` must be `<= HUF_TABLELOG_MAX` . */
83HUF_PUBLIC_API size_t HUF_compress2 (void* dst, size_t dstCapacity,
84 const void* src, size_t srcSize,
85 unsigned maxSymbolValue, unsigned tableLog);
86
87/* HUF_compress4X_wksp() :
88 * Same as HUF_compress2(), but uses externally allocated `workSpace`.
89 * `workspace` must have minimum alignment of 4, and be at least as large as HUF_WORKSPACE_SIZE */
90#define HUF_WORKSPACE_SIZE ((6 << 10) + 256)
91#define HUF_WORKSPACE_SIZE_U32 (HUF_WORKSPACE_SIZE / sizeof(U32))
92HUF_PUBLIC_API size_t HUF_compress4X_wksp (void* dst, size_t dstCapacity,
93 const void* src, size_t srcSize,
94 unsigned maxSymbolValue, unsigned tableLog,
95 void* workSpace, size_t wkspSize);
96
97#endif /* HUF_H_298734234 */
98
99/* ******************************************************************
100 * WARNING !!
101 * The following section contains advanced and experimental definitions
102 * which shall never be used in the context of a dynamic library,
103 * because they are not guaranteed to remain stable in the future.
104 * Only consider them in association with static linking.
105 * *****************************************************************/
106#if !defined(HUF_H_HUF_STATIC_LINKING_ONLY)
107#define HUF_H_HUF_STATIC_LINKING_ONLY
108
109/* *** Dependencies *** */
110#include "mem.h" /* U32 */
111#define FSE_STATIC_LINKING_ONLY
112#include "fse.h"
113
114
115/* *** Constants *** */
116#define HUF_TABLELOG_MAX 12 /* max runtime value of tableLog (due to static allocation); can be modified up to HUF_ABSOLUTEMAX_TABLELOG */
117#define HUF_TABLELOG_DEFAULT 11 /* default tableLog value when none specified */
118#define HUF_SYMBOLVALUE_MAX 255
119
120#define HUF_TABLELOG_ABSOLUTEMAX 15 /* absolute limit of HUF_MAX_TABLELOG. Beyond that value, code does not work */
121#if (HUF_TABLELOG_MAX > HUF_TABLELOG_ABSOLUTEMAX)
122# error "HUF_TABLELOG_MAX is too large !"
123#endif
124
125
126/* ****************************************
127* Static allocation
128******************************************/
129/* HUF buffer bounds */
130#define HUF_CTABLEBOUND 129
131#define HUF_BLOCKBOUND(size) (size + (size>>8) + 8) /* only true when incompressible is pre-filtered with fast heuristic */
132#define HUF_COMPRESSBOUND(size) (HUF_CTABLEBOUND + HUF_BLOCKBOUND(size)) /* Macro version, useful for static allocation */
133
134/* static allocation of HUF's Compression Table */
135/* this is a private definition, just exposed for allocation and strict aliasing purpose. never EVER access its members directly */
136struct HUF_CElt_s {
137 U16 val;
138 BYTE nbBits;
139}; /* typedef'd to HUF_CElt */
140typedef struct HUF_CElt_s HUF_CElt; /* consider it an incomplete type */
141#define HUF_CTABLE_SIZE_U32(maxSymbolValue) ((maxSymbolValue)+1) /* Use tables of U32, for proper alignment */
142#define HUF_CTABLE_SIZE(maxSymbolValue) (HUF_CTABLE_SIZE_U32(maxSymbolValue) * sizeof(U32))
143#define HUF_CREATE_STATIC_CTABLE(name, maxSymbolValue) \
144 HUF_CElt name[HUF_CTABLE_SIZE_U32(maxSymbolValue)] /* no final ; */
145
146/* static allocation of HUF's DTable */
147typedef U32 HUF_DTable;
148#define HUF_DTABLE_SIZE(maxTableLog) (1 + (1<<(maxTableLog)))
149#define HUF_CREATE_STATIC_DTABLEX1(DTable, maxTableLog) \
150 HUF_DTable DTable[HUF_DTABLE_SIZE((maxTableLog)-1)] = { ((U32)((maxTableLog)-1) * 0x01000001) }
151#define HUF_CREATE_STATIC_DTABLEX2(DTable, maxTableLog) \
152 HUF_DTable DTable[HUF_DTABLE_SIZE(maxTableLog)] = { ((U32)(maxTableLog) * 0x01000001) }
153
154
155/* ****************************************
156* Advanced decompression functions
157******************************************/
158size_t HUF_decompress4X1 (void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize); /*< single-symbol decoder */
159#ifndef HUF_FORCE_DECOMPRESS_X1
160size_t HUF_decompress4X2 (void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize); /*< double-symbols decoder */
161#endif
162
163size_t HUF_decompress4X_DCtx (HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize); /*< decodes RLE and uncompressed */
164size_t HUF_decompress4X_hufOnly(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize); /*< considers RLE and uncompressed as errors */
165size_t HUF_decompress4X_hufOnly_wksp(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize, void* workSpace, size_t wkspSize); /*< considers RLE and uncompressed as errors */
166size_t HUF_decompress4X1_DCtx(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize); /*< single-symbol decoder */
167size_t HUF_decompress4X1_DCtx_wksp(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize, void* workSpace, size_t wkspSize); /*< single-symbol decoder */
168#ifndef HUF_FORCE_DECOMPRESS_X1
169size_t HUF_decompress4X2_DCtx(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize); /*< double-symbols decoder */
170size_t HUF_decompress4X2_DCtx_wksp(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize, void* workSpace, size_t wkspSize); /*< double-symbols decoder */
171#endif
172
173
174/* ****************************************
175 * HUF detailed API
176 * ****************************************/
177
178/*! HUF_compress() does the following:
179 * 1. count symbol occurrence from source[] into table count[] using FSE_count() (exposed within "fse.h")
180 * 2. (optional) refine tableLog using HUF_optimalTableLog()
181 * 3. build Huffman table from count using HUF_buildCTable()
182 * 4. save Huffman table to memory buffer using HUF_writeCTable()
183 * 5. encode the data stream using HUF_compress4X_usingCTable()
184 *
185 * The following API allows targeting specific sub-functions for advanced tasks.
186 * For example, it's possible to compress several blocks using the same 'CTable',
187 * or to save and regenerate 'CTable' using external methods.
188 */
189unsigned HUF_optimalTableLog(unsigned maxTableLog, size_t srcSize, unsigned maxSymbolValue);
190size_t HUF_buildCTable (HUF_CElt* CTable, const unsigned* count, unsigned maxSymbolValue, unsigned maxNbBits); /* @return : maxNbBits; CTable and count can overlap. In which case, CTable will overwrite count content */
191size_t HUF_writeCTable (void* dst, size_t maxDstSize, const HUF_CElt* CTable, unsigned maxSymbolValue, unsigned huffLog);
192size_t HUF_writeCTable_wksp(void* dst, size_t maxDstSize, const HUF_CElt* CTable, unsigned maxSymbolValue, unsigned huffLog, void* workspace, size_t workspaceSize);
193size_t HUF_compress4X_usingCTable(void* dst, size_t dstSize, const void* src, size_t srcSize, const HUF_CElt* CTable);
194size_t HUF_estimateCompressedSize(const HUF_CElt* CTable, const unsigned* count, unsigned maxSymbolValue);
195int HUF_validateCTable(const HUF_CElt* CTable, const unsigned* count, unsigned maxSymbolValue);
196
197typedef enum {
198 HUF_repeat_none, /*< Cannot use the previous table */
199 HUF_repeat_check, /*< Can use the previous table but it must be checked. Note : The previous table must have been constructed by HUF_compress{1, 4}X_repeat */
200 HUF_repeat_valid /*< Can use the previous table and it is assumed to be valid */
201 } HUF_repeat;
202/* HUF_compress4X_repeat() :
203 * Same as HUF_compress4X_wksp(), but considers using hufTable if *repeat != HUF_repeat_none.
204 * If it uses hufTable it does not modify hufTable or repeat.
205 * If it doesn't, it sets *repeat = HUF_repeat_none, and it sets hufTable to the table used.
206 * If preferRepeat then the old table will always be used if valid. */
207size_t HUF_compress4X_repeat(void* dst, size_t dstSize,
208 const void* src, size_t srcSize,
209 unsigned maxSymbolValue, unsigned tableLog,
210 void* workSpace, size_t wkspSize, /*< `workSpace` must be aligned on 4-bytes boundaries, `wkspSize` must be >= HUF_WORKSPACE_SIZE */
211 HUF_CElt* hufTable, HUF_repeat* repeat, int preferRepeat, int bmi2);
212
213/* HUF_buildCTable_wksp() :
214 * Same as HUF_buildCTable(), but using externally allocated scratch buffer.
215 * `workSpace` must be aligned on 4-bytes boundaries, and its size must be >= HUF_CTABLE_WORKSPACE_SIZE.
216 */
217#define HUF_CTABLE_WORKSPACE_SIZE_U32 (2*HUF_SYMBOLVALUE_MAX +1 +1)
218#define HUF_CTABLE_WORKSPACE_SIZE (HUF_CTABLE_WORKSPACE_SIZE_U32 * sizeof(unsigned))
219size_t HUF_buildCTable_wksp (HUF_CElt* tree,
220 const unsigned* count, U32 maxSymbolValue, U32 maxNbBits,
221 void* workSpace, size_t wkspSize);
222
223/*! HUF_readStats() :
224 * Read compact Huffman tree, saved by HUF_writeCTable().
225 * `huffWeight` is destination buffer.
226 * @return : size read from `src` , or an error Code .
227 * Note : Needed by HUF_readCTable() and HUF_readDTableXn() . */
228size_t HUF_readStats(BYTE* huffWeight, size_t hwSize,
229 U32* rankStats, U32* nbSymbolsPtr, U32* tableLogPtr,
230 const void* src, size_t srcSize);
231
232/*! HUF_readStats_wksp() :
233 * Same as HUF_readStats() but takes an external workspace which must be
234 * 4-byte aligned and its size must be >= HUF_READ_STATS_WORKSPACE_SIZE.
235 * If the CPU has BMI2 support, pass bmi2=1, otherwise pass bmi2=0.
236 */
237#define HUF_READ_STATS_WORKSPACE_SIZE_U32 FSE_DECOMPRESS_WKSP_SIZE_U32(6, HUF_TABLELOG_MAX-1)
238#define HUF_READ_STATS_WORKSPACE_SIZE (HUF_READ_STATS_WORKSPACE_SIZE_U32 * sizeof(unsigned))
239size_t HUF_readStats_wksp(BYTE* huffWeight, size_t hwSize,
240 U32* rankStats, U32* nbSymbolsPtr, U32* tableLogPtr,
241 const void* src, size_t srcSize,
242 void* workspace, size_t wkspSize,
243 int bmi2);
244
245/* HUF_readCTable() :
246 * Loading a CTable saved with HUF_writeCTable() */
247size_t HUF_readCTable (HUF_CElt* CTable, unsigned* maxSymbolValuePtr, const void* src, size_t srcSize, unsigned *hasZeroWeights);
248
249/* HUF_getNbBits() :
250 * Read nbBits from CTable symbolTable, for symbol `symbolValue` presumed <= HUF_SYMBOLVALUE_MAX
251 * Note 1 : is not inlined, as HUF_CElt definition is private
252 * Note 2 : const void* used, so that it can provide a statically allocated table as argument (which uses type U32) */
253U32 HUF_getNbBits(const void* symbolTable, U32 symbolValue);
254
255/*
256 * HUF_decompress() does the following:
257 * 1. select the decompression algorithm (X1, X2) based on pre-computed heuristics
258 * 2. build Huffman table from save, using HUF_readDTableX?()
259 * 3. decode 1 or 4 segments in parallel using HUF_decompress?X?_usingDTable()
260 */
261
262/* HUF_selectDecoder() :
263 * Tells which decoder is likely to decode faster,
264 * based on a set of pre-computed metrics.
265 * @return : 0==HUF_decompress4X1, 1==HUF_decompress4X2 .
266 * Assumption : 0 < dstSize <= 128 KB */
267U32 HUF_selectDecoder (size_t dstSize, size_t cSrcSize);
268
269/*
270 * The minimum workspace size for the `workSpace` used in
271 * HUF_readDTableX1_wksp() and HUF_readDTableX2_wksp().
272 *
273 * The space used depends on HUF_TABLELOG_MAX, ranging from ~1500 bytes when
274 * HUF_TABLE_LOG_MAX=12 to ~1850 bytes when HUF_TABLE_LOG_MAX=15.
275 * Buffer overflow errors may potentially occur if code modifications result in
276 * a required workspace size greater than that specified in the following
277 * macro.
278 */
279#define HUF_DECOMPRESS_WORKSPACE_SIZE ((2 << 10) + (1 << 9))
280#define HUF_DECOMPRESS_WORKSPACE_SIZE_U32 (HUF_DECOMPRESS_WORKSPACE_SIZE / sizeof(U32))
281
282#ifndef HUF_FORCE_DECOMPRESS_X2
283size_t HUF_readDTableX1 (HUF_DTable* DTable, const void* src, size_t srcSize);
284size_t HUF_readDTableX1_wksp (HUF_DTable* DTable, const void* src, size_t srcSize, void* workSpace, size_t wkspSize);
285#endif
286#ifndef HUF_FORCE_DECOMPRESS_X1
287size_t HUF_readDTableX2 (HUF_DTable* DTable, const void* src, size_t srcSize);
288size_t HUF_readDTableX2_wksp (HUF_DTable* DTable, const void* src, size_t srcSize, void* workSpace, size_t wkspSize);
289#endif
290
291size_t HUF_decompress4X_usingDTable(void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize, const HUF_DTable* DTable);
292#ifndef HUF_FORCE_DECOMPRESS_X2
293size_t HUF_decompress4X1_usingDTable(void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize, const HUF_DTable* DTable);
294#endif
295#ifndef HUF_FORCE_DECOMPRESS_X1
296size_t HUF_decompress4X2_usingDTable(void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize, const HUF_DTable* DTable);
297#endif
298
299
300/* ====================== */
301/* single stream variants */
302/* ====================== */
303
304size_t HUF_compress1X (void* dst, size_t dstSize, const void* src, size_t srcSize, unsigned maxSymbolValue, unsigned tableLog);
305size_t HUF_compress1X_wksp (void* dst, size_t dstSize, const void* src, size_t srcSize, unsigned maxSymbolValue, unsigned tableLog, void* workSpace, size_t wkspSize); /*< `workSpace` must be a table of at least HUF_WORKSPACE_SIZE_U32 unsigned */
306size_t HUF_compress1X_usingCTable(void* dst, size_t dstSize, const void* src, size_t srcSize, const HUF_CElt* CTable);
307/* HUF_compress1X_repeat() :
308 * Same as HUF_compress1X_wksp(), but considers using hufTable if *repeat != HUF_repeat_none.
309 * If it uses hufTable it does not modify hufTable or repeat.
310 * If it doesn't, it sets *repeat = HUF_repeat_none, and it sets hufTable to the table used.
311 * If preferRepeat then the old table will always be used if valid. */
312size_t HUF_compress1X_repeat(void* dst, size_t dstSize,
313 const void* src, size_t srcSize,
314 unsigned maxSymbolValue, unsigned tableLog,
315 void* workSpace, size_t wkspSize, /*< `workSpace` must be aligned on 4-bytes boundaries, `wkspSize` must be >= HUF_WORKSPACE_SIZE */
316 HUF_CElt* hufTable, HUF_repeat* repeat, int preferRepeat, int bmi2);
317
318size_t HUF_decompress1X1 (void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize); /* single-symbol decoder */
319#ifndef HUF_FORCE_DECOMPRESS_X1
320size_t HUF_decompress1X2 (void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize); /* double-symbol decoder */
321#endif
322
323size_t HUF_decompress1X_DCtx (HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize);
324size_t HUF_decompress1X_DCtx_wksp (HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize, void* workSpace, size_t wkspSize);
325#ifndef HUF_FORCE_DECOMPRESS_X2
326size_t HUF_decompress1X1_DCtx(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize); /*< single-symbol decoder */
327size_t HUF_decompress1X1_DCtx_wksp(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize, void* workSpace, size_t wkspSize); /*< single-symbol decoder */
328#endif
329#ifndef HUF_FORCE_DECOMPRESS_X1
330size_t HUF_decompress1X2_DCtx(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize); /*< double-symbols decoder */
331size_t HUF_decompress1X2_DCtx_wksp(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize, void* workSpace, size_t wkspSize); /*< double-symbols decoder */
332#endif
333
334size_t HUF_decompress1X_usingDTable(void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize, const HUF_DTable* DTable); /*< automatic selection of sing or double symbol decoder, based on DTable */
335#ifndef HUF_FORCE_DECOMPRESS_X2
336size_t HUF_decompress1X1_usingDTable(void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize, const HUF_DTable* DTable);
337#endif
338#ifndef HUF_FORCE_DECOMPRESS_X1
339size_t HUF_decompress1X2_usingDTable(void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize, const HUF_DTable* DTable);
340#endif
341
342/* BMI2 variants.
343 * If the CPU has BMI2 support, pass bmi2=1, otherwise pass bmi2=0.
344 */
345size_t HUF_decompress1X_usingDTable_bmi2(void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize, const HUF_DTable* DTable, int bmi2);
346#ifndef HUF_FORCE_DECOMPRESS_X2
347size_t HUF_decompress1X1_DCtx_wksp_bmi2(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize, void* workSpace, size_t wkspSize, int bmi2);
348#endif
349size_t HUF_decompress4X_usingDTable_bmi2(void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize, const HUF_DTable* DTable, int bmi2);
350size_t HUF_decompress4X_hufOnly_wksp_bmi2(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize, void* workSpace, size_t wkspSize, int bmi2);
351#ifndef HUF_FORCE_DECOMPRESS_X2
352size_t HUF_readDTableX1_wksp_bmi2(HUF_DTable* DTable, const void* src, size_t srcSize, void* workSpace, size_t wkspSize, int bmi2);
353#endif
354
355#endif /* HUF_STATIC_LINKING_ONLY */
356