xref: /freebsd/sys/contrib/zstd/lib/legacy/zstd_v06.c (revision 8ddb146abcdf061be9f2c0db7e391697dafad85c)
1 /*
2  * Copyright (c) 2016-2020, 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 
12 /*- Dependencies -*/
13 #include "zstd_v06.h"
14 #include <stddef.h>    /* size_t, ptrdiff_t */
15 #include <string.h>    /* memcpy */
16 #include <stdlib.h>    /* malloc, free, qsort */
17 #include "../common/error_private.h"
18 
19 
20 
21 /* ******************************************************************
22    mem.h
23    low-level memory access routines
24    Copyright (C) 2013-2015, Yann Collet.
25 
26    BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
27 
28    Redistribution and use in source and binary forms, with or without
29    modification, are permitted provided that the following conditions are
30    met:
31 
32        * Redistributions of source code must retain the above copyright
33    notice, this list of conditions and the following disclaimer.
34        * Redistributions in binary form must reproduce the above
35    copyright notice, this list of conditions and the following disclaimer
36    in the documentation and/or other materials provided with the
37    distribution.
38 
39    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
40    "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
41    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
42    A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
43    OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
44    SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
45    LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
46    DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
47    THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
48    (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
49    OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
50 
51     You can contact the author at :
52     - FSE source repository : https://github.com/Cyan4973/FiniteStateEntropy
53     - Public forum : https://groups.google.com/forum/#!forum/lz4c
54 ****************************************************************** */
55 #ifndef MEM_H_MODULE
56 #define MEM_H_MODULE
57 
58 #if defined (__cplusplus)
59 extern "C" {
60 #endif
61 
62 
63 /*-****************************************
64 *  Compiler specifics
65 ******************************************/
66 #if defined(_MSC_VER)   /* Visual Studio */
67 #   include <stdlib.h>  /* _byteswap_ulong */
68 #   include <intrin.h>  /* _byteswap_* */
69 #endif
70 #if defined(__GNUC__)
71 #  define MEM_STATIC static __attribute__((unused))
72 #elif defined (__cplusplus) || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */)
73 #  define MEM_STATIC static inline
74 #elif defined(_MSC_VER)
75 #  define MEM_STATIC static __inline
76 #else
77 #  define MEM_STATIC static  /* this version may generate warnings for unused static functions; disable the relevant warning */
78 #endif
79 
80 
81 /*-**************************************************************
82 *  Basic Types
83 *****************************************************************/
84 #if  !defined (__VMS) && (defined (__cplusplus) || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */) )
85 # if defined(_AIX)
86 #  include <inttypes.h>
87 # else
88 #  include <stdint.h> /* intptr_t */
89 # endif
90   typedef  uint8_t BYTE;
91   typedef uint16_t U16;
92   typedef  int16_t S16;
93   typedef uint32_t U32;
94   typedef  int32_t S32;
95   typedef uint64_t U64;
96   typedef  int64_t S64;
97 #else
98   typedef unsigned char       BYTE;
99   typedef unsigned short      U16;
100   typedef   signed short      S16;
101   typedef unsigned int        U32;
102   typedef   signed int        S32;
103   typedef unsigned long long  U64;
104   typedef   signed long long  S64;
105 #endif
106 
107 
108 /*-**************************************************************
109 *  Memory I/O
110 *****************************************************************/
111 /* MEM_FORCE_MEMORY_ACCESS :
112  * By default, access to unaligned memory is controlled by `memcpy()`, which is safe and portable.
113  * Unfortunately, on some target/compiler combinations, the generated assembly is sub-optimal.
114  * The below switch allow to select different access method for improved performance.
115  * Method 0 (default) : use `memcpy()`. Safe and portable.
116  * Method 1 : `__packed` statement. It depends on compiler extension (ie, not portable).
117  *            This method is safe if your compiler supports it, and *generally* as fast or faster than `memcpy`.
118  * Method 2 : direct access. This method is portable but violate C standard.
119  *            It can generate buggy code on targets depending on alignment.
120  *            In some circumstances, it's the only known way to get the most performance (ie GCC + ARMv6)
121  * See http://fastcompression.blogspot.fr/2015/08/accessing-unaligned-memory.html for details.
122  * Prefer these methods in priority order (0 > 1 > 2)
123  */
124 #ifndef MEM_FORCE_MEMORY_ACCESS   /* can be defined externally, on command line for example */
125 #  if defined(__GNUC__) && ( defined(__ARM_ARCH_6__) || defined(__ARM_ARCH_6J__) || defined(__ARM_ARCH_6K__) || defined(__ARM_ARCH_6Z__) || defined(__ARM_ARCH_6ZK__) || defined(__ARM_ARCH_6T2__) )
126 #    define MEM_FORCE_MEMORY_ACCESS 2
127 #  elif (defined(__INTEL_COMPILER) && !defined(WIN32)) || \
128   (defined(__GNUC__) && ( defined(__ARM_ARCH_7__) || defined(__ARM_ARCH_7A__) || defined(__ARM_ARCH_7R__) || defined(__ARM_ARCH_7M__) || defined(__ARM_ARCH_7S__) ))
129 #    define MEM_FORCE_MEMORY_ACCESS 1
130 #  endif
131 #endif
132 
133 MEM_STATIC unsigned MEM_32bits(void) { return sizeof(size_t)==4; }
134 MEM_STATIC unsigned MEM_64bits(void) { return sizeof(size_t)==8; }
135 
136 MEM_STATIC unsigned MEM_isLittleEndian(void)
137 {
138     const union { U32 u; BYTE c[4]; } one = { 1 };   /* don't use static : performance detrimental  */
139     return one.c[0];
140 }
141 
142 #if defined(MEM_FORCE_MEMORY_ACCESS) && (MEM_FORCE_MEMORY_ACCESS==2)
143 
144 /* violates C standard, by lying on structure alignment.
145 Only use if no other choice to achieve best performance on target platform */
146 MEM_STATIC U16 MEM_read16(const void* memPtr) { return *(const U16*) memPtr; }
147 MEM_STATIC U32 MEM_read32(const void* memPtr) { return *(const U32*) memPtr; }
148 MEM_STATIC U64 MEM_read64(const void* memPtr) { return *(const U64*) memPtr; }
149 
150 MEM_STATIC void MEM_write16(void* memPtr, U16 value) { *(U16*)memPtr = value; }
151 
152 #elif defined(MEM_FORCE_MEMORY_ACCESS) && (MEM_FORCE_MEMORY_ACCESS==1)
153 
154 /* __pack instructions are safer, but compiler specific, hence potentially problematic for some compilers */
155 /* currently only defined for gcc and icc */
156 typedef union { U16 u16; U32 u32; U64 u64; size_t st; } __attribute__((packed)) unalign;
157 
158 MEM_STATIC U16 MEM_read16(const void* ptr) { return ((const unalign*)ptr)->u16; }
159 MEM_STATIC U32 MEM_read32(const void* ptr) { return ((const unalign*)ptr)->u32; }
160 MEM_STATIC U64 MEM_read64(const void* ptr) { return ((const unalign*)ptr)->u64; }
161 
162 MEM_STATIC void MEM_write16(void* memPtr, U16 value) { ((unalign*)memPtr)->u16 = value; }
163 
164 #else
165 
166 /* default method, safe and standard.
167    can sometimes prove slower */
168 
169 MEM_STATIC U16 MEM_read16(const void* memPtr)
170 {
171     U16 val; memcpy(&val, memPtr, sizeof(val)); return val;
172 }
173 
174 MEM_STATIC U32 MEM_read32(const void* memPtr)
175 {
176     U32 val; memcpy(&val, memPtr, sizeof(val)); return val;
177 }
178 
179 MEM_STATIC U64 MEM_read64(const void* memPtr)
180 {
181     U64 val; memcpy(&val, memPtr, sizeof(val)); return val;
182 }
183 
184 MEM_STATIC void MEM_write16(void* memPtr, U16 value)
185 {
186     memcpy(memPtr, &value, sizeof(value));
187 }
188 
189 
190 #endif /* MEM_FORCE_MEMORY_ACCESS */
191 
192 MEM_STATIC U32 MEM_swap32(U32 in)
193 {
194 #if defined(_MSC_VER)     /* Visual Studio */
195     return _byteswap_ulong(in);
196 #elif defined (__GNUC__) && (__GNUC__ * 100 + __GNUC_MINOR__ >= 403)
197     return __builtin_bswap32(in);
198 #else
199     return  ((in << 24) & 0xff000000 ) |
200             ((in <<  8) & 0x00ff0000 ) |
201             ((in >>  8) & 0x0000ff00 ) |
202             ((in >> 24) & 0x000000ff );
203 #endif
204 }
205 
206 MEM_STATIC U64 MEM_swap64(U64 in)
207 {
208 #if defined(_MSC_VER)     /* Visual Studio */
209     return _byteswap_uint64(in);
210 #elif defined (__GNUC__) && (__GNUC__ * 100 + __GNUC_MINOR__ >= 403)
211     return __builtin_bswap64(in);
212 #else
213     return  ((in << 56) & 0xff00000000000000ULL) |
214             ((in << 40) & 0x00ff000000000000ULL) |
215             ((in << 24) & 0x0000ff0000000000ULL) |
216             ((in << 8)  & 0x000000ff00000000ULL) |
217             ((in >> 8)  & 0x00000000ff000000ULL) |
218             ((in >> 24) & 0x0000000000ff0000ULL) |
219             ((in >> 40) & 0x000000000000ff00ULL) |
220             ((in >> 56) & 0x00000000000000ffULL);
221 #endif
222 }
223 
224 
225 /*=== Little endian r/w ===*/
226 
227 MEM_STATIC U16 MEM_readLE16(const void* memPtr)
228 {
229     if (MEM_isLittleEndian())
230         return MEM_read16(memPtr);
231     else {
232         const BYTE* p = (const BYTE*)memPtr;
233         return (U16)(p[0] + (p[1]<<8));
234     }
235 }
236 
237 MEM_STATIC void MEM_writeLE16(void* memPtr, U16 val)
238 {
239     if (MEM_isLittleEndian()) {
240         MEM_write16(memPtr, val);
241     } else {
242         BYTE* p = (BYTE*)memPtr;
243         p[0] = (BYTE)val;
244         p[1] = (BYTE)(val>>8);
245     }
246 }
247 
248 MEM_STATIC U32 MEM_readLE32(const void* memPtr)
249 {
250     if (MEM_isLittleEndian())
251         return MEM_read32(memPtr);
252     else
253         return MEM_swap32(MEM_read32(memPtr));
254 }
255 
256 
257 MEM_STATIC U64 MEM_readLE64(const void* memPtr)
258 {
259     if (MEM_isLittleEndian())
260         return MEM_read64(memPtr);
261     else
262         return MEM_swap64(MEM_read64(memPtr));
263 }
264 
265 
266 MEM_STATIC size_t MEM_readLEST(const void* memPtr)
267 {
268     if (MEM_32bits())
269         return (size_t)MEM_readLE32(memPtr);
270     else
271         return (size_t)MEM_readLE64(memPtr);
272 }
273 
274 
275 
276 #if defined (__cplusplus)
277 }
278 #endif
279 
280 #endif /* MEM_H_MODULE */
281 
282 /*
283     zstd - standard compression library
284     Header File for static linking only
285     Copyright (C) 2014-2016, Yann Collet.
286 
287     BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
288 
289     Redistribution and use in source and binary forms, with or without
290     modification, are permitted provided that the following conditions are
291     met:
292     * Redistributions of source code must retain the above copyright
293     notice, this list of conditions and the following disclaimer.
294     * Redistributions in binary form must reproduce the above
295     copyright notice, this list of conditions and the following disclaimer
296     in the documentation and/or other materials provided with the
297     distribution.
298     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
299     "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
300     LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
301     A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
302     OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
303     SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
304     LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
305     DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
306     THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
307     (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
308     OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
309 
310     You can contact the author at :
311     - zstd homepage : http://www.zstd.net
312 */
313 #ifndef ZSTDv06_STATIC_H
314 #define ZSTDv06_STATIC_H
315 
316 /* The prototypes defined within this file are considered experimental.
317  * They should not be used in the context DLL as they may change in the future.
318  * Prefer static linking if you need them, to control breaking version changes issues.
319  */
320 
321 #if defined (__cplusplus)
322 extern "C" {
323 #endif
324 
325 
326 
327 /*- Advanced Decompression functions -*/
328 
329 /*! ZSTDv06_decompress_usingPreparedDCtx() :
330 *   Same as ZSTDv06_decompress_usingDict, but using a reference context `preparedDCtx`, where dictionary has been loaded.
331 *   It avoids reloading the dictionary each time.
332 *   `preparedDCtx` must have been properly initialized using ZSTDv06_decompressBegin_usingDict().
333 *   Requires 2 contexts : 1 for reference (preparedDCtx), which will not be modified, and 1 to run the decompression operation (dctx) */
334 ZSTDLIBv06_API size_t ZSTDv06_decompress_usingPreparedDCtx(
335                                            ZSTDv06_DCtx* dctx, const ZSTDv06_DCtx* preparedDCtx,
336                                            void* dst, size_t dstCapacity,
337                                      const void* src, size_t srcSize);
338 
339 
340 
341 #define ZSTDv06_FRAMEHEADERSIZE_MAX 13    /* for static allocation */
342 static const size_t ZSTDv06_frameHeaderSize_min = 5;
343 static const size_t ZSTDv06_frameHeaderSize_max = ZSTDv06_FRAMEHEADERSIZE_MAX;
344 
345 ZSTDLIBv06_API size_t ZSTDv06_decompressBegin(ZSTDv06_DCtx* dctx);
346 
347 /*
348   Streaming decompression, direct mode (bufferless)
349 
350   A ZSTDv06_DCtx object is required to track streaming operations.
351   Use ZSTDv06_createDCtx() / ZSTDv06_freeDCtx() to manage it.
352   A ZSTDv06_DCtx object can be re-used multiple times.
353 
354   First optional operation is to retrieve frame parameters, using ZSTDv06_getFrameParams(), which doesn't consume the input.
355   It can provide the minimum size of rolling buffer required to properly decompress data,
356   and optionally the final size of uncompressed content.
357   (Note : content size is an optional info that may not be present. 0 means : content size unknown)
358   Frame parameters are extracted from the beginning of compressed frame.
359   The amount of data to read is variable, from ZSTDv06_frameHeaderSize_min to ZSTDv06_frameHeaderSize_max (so if `srcSize` >= ZSTDv06_frameHeaderSize_max, it will always work)
360   If `srcSize` is too small for operation to succeed, function will return the minimum size it requires to produce a result.
361   Result : 0 when successful, it means the ZSTDv06_frameParams structure has been filled.
362           >0 : means there is not enough data into `src`. Provides the expected size to successfully decode header.
363            errorCode, which can be tested using ZSTDv06_isError()
364 
365   Start decompression, with ZSTDv06_decompressBegin() or ZSTDv06_decompressBegin_usingDict().
366   Alternatively, you can copy a prepared context, using ZSTDv06_copyDCtx().
367 
368   Then use ZSTDv06_nextSrcSizeToDecompress() and ZSTDv06_decompressContinue() alternatively.
369   ZSTDv06_nextSrcSizeToDecompress() tells how much bytes to provide as 'srcSize' to ZSTDv06_decompressContinue().
370   ZSTDv06_decompressContinue() requires this exact amount of bytes, or it will fail.
371   ZSTDv06_decompressContinue() needs previous data blocks during decompression, up to (1 << windowlog).
372   They should preferably be located contiguously, prior to current block. Alternatively, a round buffer is also possible.
373 
374   @result of ZSTDv06_decompressContinue() is the number of bytes regenerated within 'dst' (necessarily <= dstCapacity)
375   It can be zero, which is not an error; it just means ZSTDv06_decompressContinue() has decoded some header.
376 
377   A frame is fully decoded when ZSTDv06_nextSrcSizeToDecompress() returns zero.
378   Context can then be reset to start a new decompression.
379 */
380 
381 
382 /* **************************************
383 *  Block functions
384 ****************************************/
385 /*! Block functions produce and decode raw zstd blocks, without frame metadata.
386     User will have to take in charge required information to regenerate data, such as compressed and content sizes.
387 
388     A few rules to respect :
389     - Uncompressed block size must be <= ZSTDv06_BLOCKSIZE_MAX (128 KB)
390     - Compressing or decompressing requires a context structure
391       + Use ZSTDv06_createCCtx() and ZSTDv06_createDCtx()
392     - It is necessary to init context before starting
393       + compression : ZSTDv06_compressBegin()
394       + decompression : ZSTDv06_decompressBegin()
395       + variants _usingDict() are also allowed
396       + copyCCtx() and copyDCtx() work too
397     - When a block is considered not compressible enough, ZSTDv06_compressBlock() result will be zero.
398       In which case, nothing is produced into `dst`.
399       + User must test for such outcome and deal directly with uncompressed data
400       + ZSTDv06_decompressBlock() doesn't accept uncompressed data as input !!
401 */
402 
403 #define ZSTDv06_BLOCKSIZE_MAX (128 * 1024)   /* define, for static allocation */
404 ZSTDLIBv06_API size_t ZSTDv06_decompressBlock(ZSTDv06_DCtx* dctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize);
405 
406 
407 
408 #if defined (__cplusplus)
409 }
410 #endif
411 
412 #endif  /* ZSTDv06_STATIC_H */
413 /*
414     zstd_internal - common functions to include
415     Header File for include
416     Copyright (C) 2014-2016, Yann Collet.
417 
418     BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
419 
420     Redistribution and use in source and binary forms, with or without
421     modification, are permitted provided that the following conditions are
422     met:
423     * Redistributions of source code must retain the above copyright
424     notice, this list of conditions and the following disclaimer.
425     * Redistributions in binary form must reproduce the above
426     copyright notice, this list of conditions and the following disclaimer
427     in the documentation and/or other materials provided with the
428     distribution.
429     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
430     "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
431     LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
432     A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
433     OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
434     SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
435     LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
436     DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
437     THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
438     (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
439     OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
440 
441     You can contact the author at :
442     - zstd homepage : https://www.zstd.net
443 */
444 #ifndef ZSTDv06_CCOMMON_H_MODULE
445 #define ZSTDv06_CCOMMON_H_MODULE
446 
447 
448 /*-*************************************
449 *  Common macros
450 ***************************************/
451 #define MIN(a,b) ((a)<(b) ? (a) : (b))
452 #define MAX(a,b) ((a)>(b) ? (a) : (b))
453 
454 
455 /*-*************************************
456 *  Common constants
457 ***************************************/
458 #define ZSTDv06_DICT_MAGIC  0xEC30A436
459 
460 #define ZSTDv06_REP_NUM    3
461 #define ZSTDv06_REP_INIT   ZSTDv06_REP_NUM
462 #define ZSTDv06_REP_MOVE   (ZSTDv06_REP_NUM-1)
463 
464 #define KB *(1 <<10)
465 #define MB *(1 <<20)
466 #define GB *(1U<<30)
467 
468 #define BIT7 128
469 #define BIT6  64
470 #define BIT5  32
471 #define BIT4  16
472 #define BIT1   2
473 #define BIT0   1
474 
475 #define ZSTDv06_WINDOWLOG_ABSOLUTEMIN 12
476 static const size_t ZSTDv06_fcs_fieldSize[4] = { 0, 1, 2, 8 };
477 
478 #define ZSTDv06_BLOCKHEADERSIZE 3   /* because C standard does not allow a static const value to be defined using another static const value .... :( */
479 static const size_t ZSTDv06_blockHeaderSize = ZSTDv06_BLOCKHEADERSIZE;
480 typedef enum { bt_compressed, bt_raw, bt_rle, bt_end } blockType_t;
481 
482 #define MIN_SEQUENCES_SIZE 1 /* nbSeq==0 */
483 #define MIN_CBLOCK_SIZE (1 /*litCSize*/ + 1 /* RLE or RAW */ + MIN_SEQUENCES_SIZE /* nbSeq==0 */)   /* for a non-null block */
484 
485 #define HufLog 12
486 
487 #define IS_HUF 0
488 #define IS_PCH 1
489 #define IS_RAW 2
490 #define IS_RLE 3
491 
492 #define LONGNBSEQ 0x7F00
493 
494 #define MINMATCH 3
495 #define EQUAL_READ32 4
496 #define REPCODE_STARTVALUE 1
497 
498 #define Litbits  8
499 #define MaxLit ((1<<Litbits) - 1)
500 #define MaxML  52
501 #define MaxLL  35
502 #define MaxOff 28
503 #define MaxSeq MAX(MaxLL, MaxML)   /* Assumption : MaxOff < MaxLL,MaxML */
504 #define MLFSELog    9
505 #define LLFSELog    9
506 #define OffFSELog   8
507 
508 #define FSEv06_ENCODING_RAW     0
509 #define FSEv06_ENCODING_RLE     1
510 #define FSEv06_ENCODING_STATIC  2
511 #define FSEv06_ENCODING_DYNAMIC 3
512 
513 #define ZSTD_CONTENTSIZE_ERROR   (0ULL - 2)
514 
515 static const U32 LL_bits[MaxLL+1] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
516                                       1, 1, 1, 1, 2, 2, 3, 3, 4, 6, 7, 8, 9,10,11,12,
517                                      13,14,15,16 };
518 static const S16 LL_defaultNorm[MaxLL+1] = { 4, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 1,
519                                              2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 2, 1, 1, 1, 1, 1,
520                                             -1,-1,-1,-1 };
521 static const U32 LL_defaultNormLog = 6;
522 
523 static const U32 ML_bits[MaxML+1] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
524                                       0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
525                                       1, 1, 1, 1, 2, 2, 3, 3, 4, 4, 5, 7, 8, 9,10,11,
526                                      12,13,14,15,16 };
527 static const S16 ML_defaultNorm[MaxML+1] = { 1, 4, 3, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1,
528                                              1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
529                                              1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,-1,-1,
530                                             -1,-1,-1,-1,-1 };
531 static const U32 ML_defaultNormLog = 6;
532 
533 static const S16 OF_defaultNorm[MaxOff+1] = { 1, 1, 1, 1, 1, 1, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1,
534                                               1, 1, 1, 1, 1, 1, 1, 1,-1,-1,-1,-1,-1 };
535 static const U32 OF_defaultNormLog = 5;
536 
537 
538 /*-*******************************************
539 *  Shared functions to include for inlining
540 *********************************************/
541 static void ZSTDv06_copy8(void* dst, const void* src) { memcpy(dst, src, 8); }
542 #define COPY8(d,s) { ZSTDv06_copy8(d,s); d+=8; s+=8; }
543 
544 /*! ZSTDv06_wildcopy() :
545 *   custom version of memcpy(), can copy up to 7 bytes too many (8 bytes if length==0) */
546 #define WILDCOPY_OVERLENGTH 8
547 MEM_STATIC void ZSTDv06_wildcopy(void* dst, const void* src, ptrdiff_t length)
548 {
549     const BYTE* ip = (const BYTE*)src;
550     BYTE* op = (BYTE*)dst;
551     BYTE* const oend = op + length;
552     do
553         COPY8(op, ip)
554     while (op < oend);
555 }
556 
557 
558 
559 /*-*******************************************
560 *  Private interfaces
561 *********************************************/
562 typedef struct {
563     U32 off;
564     U32 len;
565 } ZSTDv06_match_t;
566 
567 typedef struct {
568     U32 price;
569     U32 off;
570     U32 mlen;
571     U32 litlen;
572     U32 rep[ZSTDv06_REP_INIT];
573 } ZSTDv06_optimal_t;
574 
575 typedef struct { U32  unused; } ZSTDv06_stats_t;
576 
577 typedef struct {
578     void* buffer;
579     U32*  offsetStart;
580     U32*  offset;
581     BYTE* offCodeStart;
582     BYTE* litStart;
583     BYTE* lit;
584     U16*  litLengthStart;
585     U16*  litLength;
586     BYTE* llCodeStart;
587     U16*  matchLengthStart;
588     U16*  matchLength;
589     BYTE* mlCodeStart;
590     U32   longLengthID;   /* 0 == no longLength; 1 == Lit.longLength; 2 == Match.longLength; */
591     U32   longLengthPos;
592     /* opt */
593     ZSTDv06_optimal_t* priceTable;
594     ZSTDv06_match_t* matchTable;
595     U32* matchLengthFreq;
596     U32* litLengthFreq;
597     U32* litFreq;
598     U32* offCodeFreq;
599     U32  matchLengthSum;
600     U32  matchSum;
601     U32  litLengthSum;
602     U32  litSum;
603     U32  offCodeSum;
604     U32  log2matchLengthSum;
605     U32  log2matchSum;
606     U32  log2litLengthSum;
607     U32  log2litSum;
608     U32  log2offCodeSum;
609     U32  factor;
610     U32  cachedPrice;
611     U32  cachedLitLength;
612     const BYTE* cachedLiterals;
613     ZSTDv06_stats_t stats;
614 } seqStore_t;
615 
616 void ZSTDv06_seqToCodes(const seqStore_t* seqStorePtr, size_t const nbSeq);
617 
618 
619 #endif   /* ZSTDv06_CCOMMON_H_MODULE */
620 /* ******************************************************************
621    FSE : Finite State Entropy codec
622    Public Prototypes declaration
623    Copyright (C) 2013-2016, Yann Collet.
624 
625    BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
626 
627    Redistribution and use in source and binary forms, with or without
628    modification, are permitted provided that the following conditions are
629    met:
630 
631        * Redistributions of source code must retain the above copyright
632    notice, this list of conditions and the following disclaimer.
633        * Redistributions in binary form must reproduce the above
634    copyright notice, this list of conditions and the following disclaimer
635    in the documentation and/or other materials provided with the
636    distribution.
637 
638    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
639    "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
640    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
641    A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
642    OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
643    SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
644    LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
645    DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
646    THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
647    (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
648    OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
649 
650    You can contact the author at :
651    - Source repository : https://github.com/Cyan4973/FiniteStateEntropy
652 ****************************************************************** */
653 #ifndef FSEv06_H
654 #define FSEv06_H
655 
656 #if defined (__cplusplus)
657 extern "C" {
658 #endif
659 
660 
661 
662 /*-****************************************
663 *  FSE simple functions
664 ******************************************/
665 /*! FSEv06_decompress():
666     Decompress FSE data from buffer 'cSrc', of size 'cSrcSize',
667     into already allocated destination buffer 'dst', of size 'dstCapacity'.
668     @return : size of regenerated data (<= maxDstSize),
669               or an error code, which can be tested using FSEv06_isError() .
670 
671     ** Important ** : FSEv06_decompress() does not decompress non-compressible nor RLE data !!!
672     Why ? : making this distinction requires a header.
673     Header management is intentionally delegated to the user layer, which can better manage special cases.
674 */
675 size_t FSEv06_decompress(void* dst,  size_t dstCapacity,
676                 const void* cSrc, size_t cSrcSize);
677 
678 
679 /*-*****************************************
680 *  Tool functions
681 ******************************************/
682 size_t FSEv06_compressBound(size_t size);       /* maximum compressed size */
683 
684 /* Error Management */
685 unsigned    FSEv06_isError(size_t code);        /* tells if a return value is an error code */
686 const char* FSEv06_getErrorName(size_t code);   /* provides error code string (useful for debugging) */
687 
688 
689 
690 /*-*****************************************
691 *  FSE detailed API
692 ******************************************/
693 /*!
694 
695 FSEv06_decompress() does the following:
696 1. read normalized counters with readNCount()
697 2. build decoding table 'DTable' from normalized counters
698 3. decode the data stream using decoding table 'DTable'
699 
700 The following API allows targeting specific sub-functions for advanced tasks.
701 For example, it's possible to compress several blocks using the same 'CTable',
702 or to save and provide normalized distribution using external method.
703 */
704 
705 
706 /* *** DECOMPRESSION *** */
707 
708 /*! FSEv06_readNCount():
709     Read compactly saved 'normalizedCounter' from 'rBuffer'.
710     @return : size read from 'rBuffer',
711               or an errorCode, which can be tested using FSEv06_isError().
712               maxSymbolValuePtr[0] and tableLogPtr[0] will also be updated with their respective values */
713 size_t FSEv06_readNCount (short* normalizedCounter, unsigned* maxSymbolValuePtr, unsigned* tableLogPtr, const void* rBuffer, size_t rBuffSize);
714 
715 /*! Constructor and Destructor of FSEv06_DTable.
716     Note that its size depends on 'tableLog' */
717 typedef unsigned FSEv06_DTable;   /* don't allocate that. It's just a way to be more restrictive than void* */
718 FSEv06_DTable* FSEv06_createDTable(unsigned tableLog);
719 void        FSEv06_freeDTable(FSEv06_DTable* dt);
720 
721 /*! FSEv06_buildDTable():
722     Builds 'dt', which must be already allocated, using FSEv06_createDTable().
723     return : 0, or an errorCode, which can be tested using FSEv06_isError() */
724 size_t FSEv06_buildDTable (FSEv06_DTable* dt, const short* normalizedCounter, unsigned maxSymbolValue, unsigned tableLog);
725 
726 /*! FSEv06_decompress_usingDTable():
727     Decompress compressed source `cSrc` of size `cSrcSize` using `dt`
728     into `dst` which must be already allocated.
729     @return : size of regenerated data (necessarily <= `dstCapacity`),
730               or an errorCode, which can be tested using FSEv06_isError() */
731 size_t FSEv06_decompress_usingDTable(void* dst, size_t dstCapacity, const void* cSrc, size_t cSrcSize, const FSEv06_DTable* dt);
732 
733 /*!
734 Tutorial :
735 ----------
736 (Note : these functions only decompress FSE-compressed blocks.
737  If block is uncompressed, use memcpy() instead
738  If block is a single repeated byte, use memset() instead )
739 
740 The first step is to obtain the normalized frequencies of symbols.
741 This can be performed by FSEv06_readNCount() if it was saved using FSEv06_writeNCount().
742 'normalizedCounter' must be already allocated, and have at least 'maxSymbolValuePtr[0]+1' cells of signed short.
743 In practice, that means it's necessary to know 'maxSymbolValue' beforehand,
744 or size the table to handle worst case situations (typically 256).
745 FSEv06_readNCount() will provide 'tableLog' and 'maxSymbolValue'.
746 The result of FSEv06_readNCount() is the number of bytes read from 'rBuffer'.
747 Note that 'rBufferSize' must be at least 4 bytes, even if useful information is less than that.
748 If there is an error, the function will return an error code, which can be tested using FSEv06_isError().
749 
750 The next step is to build the decompression tables 'FSEv06_DTable' from 'normalizedCounter'.
751 This is performed by the function FSEv06_buildDTable().
752 The space required by 'FSEv06_DTable' must be already allocated using FSEv06_createDTable().
753 If there is an error, the function will return an error code, which can be tested using FSEv06_isError().
754 
755 `FSEv06_DTable` can then be used to decompress `cSrc`, with FSEv06_decompress_usingDTable().
756 `cSrcSize` must be strictly correct, otherwise decompression will fail.
757 FSEv06_decompress_usingDTable() result will tell how many bytes were regenerated (<=`dstCapacity`).
758 If there is an error, the function will return an error code, which can be tested using FSEv06_isError(). (ex: dst buffer too small)
759 */
760 
761 
762 #if defined (__cplusplus)
763 }
764 #endif
765 
766 #endif  /* FSEv06_H */
767 /* ******************************************************************
768    bitstream
769    Part of FSE library
770    header file (to include)
771    Copyright (C) 2013-2016, Yann Collet.
772 
773    BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
774 
775    Redistribution and use in source and binary forms, with or without
776    modification, are permitted provided that the following conditions are
777    met:
778 
779        * Redistributions of source code must retain the above copyright
780    notice, this list of conditions and the following disclaimer.
781        * Redistributions in binary form must reproduce the above
782    copyright notice, this list of conditions and the following disclaimer
783    in the documentation and/or other materials provided with the
784    distribution.
785 
786    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
787    "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
788    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
789    A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
790    OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
791    SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
792    LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
793    DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
794    THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
795    (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
796    OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
797 
798    You can contact the author at :
799    - Source repository : https://github.com/Cyan4973/FiniteStateEntropy
800 ****************************************************************** */
801 #ifndef BITSTREAM_H_MODULE
802 #define BITSTREAM_H_MODULE
803 
804 #if defined (__cplusplus)
805 extern "C" {
806 #endif
807 
808 
809 /*
810 *  This API consists of small unitary functions, which must be inlined for best performance.
811 *  Since link-time-optimization is not available for all compilers,
812 *  these functions are defined into a .h to be included.
813 */
814 
815 
816 /*=========================================
817 *  Target specific
818 =========================================*/
819 #if defined(__BMI__) && defined(__GNUC__)
820 #  include <immintrin.h>   /* support for bextr (experimental) */
821 #endif
822 
823 
824 
825 /*-********************************************
826 *  bitStream decoding API (read backward)
827 **********************************************/
828 typedef struct
829 {
830     size_t   bitContainer;
831     unsigned bitsConsumed;
832     const char* ptr;
833     const char* start;
834 } BITv06_DStream_t;
835 
836 typedef enum { BITv06_DStream_unfinished = 0,
837                BITv06_DStream_endOfBuffer = 1,
838                BITv06_DStream_completed = 2,
839                BITv06_DStream_overflow = 3 } BITv06_DStream_status;  /* result of BITv06_reloadDStream() */
840                /* 1,2,4,8 would be better for bitmap combinations, but slows down performance a bit ... :( */
841 
842 MEM_STATIC size_t   BITv06_initDStream(BITv06_DStream_t* bitD, const void* srcBuffer, size_t srcSize);
843 MEM_STATIC size_t   BITv06_readBits(BITv06_DStream_t* bitD, unsigned nbBits);
844 MEM_STATIC BITv06_DStream_status BITv06_reloadDStream(BITv06_DStream_t* bitD);
845 MEM_STATIC unsigned BITv06_endOfDStream(const BITv06_DStream_t* bitD);
846 
847 
848 
849 /*-****************************************
850 *  unsafe API
851 ******************************************/
852 MEM_STATIC size_t BITv06_readBitsFast(BITv06_DStream_t* bitD, unsigned nbBits);
853 /* faster, but works only if nbBits >= 1 */
854 
855 
856 
857 /*-**************************************************************
858 *  Internal functions
859 ****************************************************************/
860 MEM_STATIC unsigned BITv06_highbit32 ( U32 val)
861 {
862 #   if defined(_MSC_VER)   /* Visual */
863     unsigned long r=0;
864     _BitScanReverse ( &r, val );
865     return (unsigned) r;
866 #   elif defined(__GNUC__) && (__GNUC__ >= 3)   /* Use GCC Intrinsic */
867     return __builtin_clz (val) ^ 31;
868 #   else   /* Software version */
869     static const unsigned DeBruijnClz[32] = { 0, 9, 1, 10, 13, 21, 2, 29, 11, 14, 16, 18, 22, 25, 3, 30, 8, 12, 20, 28, 15, 17, 24, 7, 19, 27, 23, 6, 26, 5, 4, 31 };
870     U32 v = val;
871     unsigned r;
872     v |= v >> 1;
873     v |= v >> 2;
874     v |= v >> 4;
875     v |= v >> 8;
876     v |= v >> 16;
877     r = DeBruijnClz[ (U32) (v * 0x07C4ACDDU) >> 27];
878     return r;
879 #   endif
880 }
881 
882 
883 
884 /*-********************************************************
885 * bitStream decoding
886 **********************************************************/
887 /*! BITv06_initDStream() :
888 *   Initialize a BITv06_DStream_t.
889 *   `bitD` : a pointer to an already allocated BITv06_DStream_t structure.
890 *   `srcSize` must be the *exact* size of the bitStream, in bytes.
891 *   @return : size of stream (== srcSize) or an errorCode if a problem is detected
892 */
893 MEM_STATIC size_t BITv06_initDStream(BITv06_DStream_t* bitD, const void* srcBuffer, size_t srcSize)
894 {
895     if (srcSize < 1) { memset(bitD, 0, sizeof(*bitD)); return ERROR(srcSize_wrong); }
896 
897     if (srcSize >=  sizeof(bitD->bitContainer)) {  /* normal case */
898         bitD->start = (const char*)srcBuffer;
899         bitD->ptr   = (const char*)srcBuffer + srcSize - sizeof(bitD->bitContainer);
900         bitD->bitContainer = MEM_readLEST(bitD->ptr);
901         { BYTE const lastByte = ((const BYTE*)srcBuffer)[srcSize-1];
902           if (lastByte == 0) return ERROR(GENERIC);   /* endMark not present */
903           bitD->bitsConsumed = 8 - BITv06_highbit32(lastByte); }
904     } else {
905         bitD->start = (const char*)srcBuffer;
906         bitD->ptr   = bitD->start;
907         bitD->bitContainer = *(const BYTE*)(bitD->start);
908         switch(srcSize)
909         {
910             case 7: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[6]) << (sizeof(bitD->bitContainer)*8 - 16);/* fall-through */
911             case 6: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[5]) << (sizeof(bitD->bitContainer)*8 - 24);/* fall-through */
912             case 5: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[4]) << (sizeof(bitD->bitContainer)*8 - 32);/* fall-through */
913             case 4: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[3]) << 24; /* fall-through */
914             case 3: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[2]) << 16; /* fall-through */
915             case 2: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[1]) <<  8; /* fall-through */
916             default: break;
917         }
918         { BYTE const lastByte = ((const BYTE*)srcBuffer)[srcSize-1];
919           if (lastByte == 0) return ERROR(GENERIC);   /* endMark not present */
920           bitD->bitsConsumed = 8 - BITv06_highbit32(lastByte); }
921         bitD->bitsConsumed += (U32)(sizeof(bitD->bitContainer) - srcSize)*8;
922     }
923 
924     return srcSize;
925 }
926 
927 
928  MEM_STATIC size_t BITv06_lookBits(const BITv06_DStream_t* bitD, U32 nbBits)
929 {
930     U32 const bitMask = sizeof(bitD->bitContainer)*8 - 1;
931     return ((bitD->bitContainer << (bitD->bitsConsumed & bitMask)) >> 1) >> ((bitMask-nbBits) & bitMask);
932 }
933 
934 /*! BITv06_lookBitsFast() :
935 *   unsafe version; only works only if nbBits >= 1 */
936 MEM_STATIC size_t BITv06_lookBitsFast(const BITv06_DStream_t* bitD, U32 nbBits)
937 {
938     U32 const bitMask = sizeof(bitD->bitContainer)*8 - 1;
939     return (bitD->bitContainer << (bitD->bitsConsumed & bitMask)) >> (((bitMask+1)-nbBits) & bitMask);
940 }
941 
942 MEM_STATIC void BITv06_skipBits(BITv06_DStream_t* bitD, U32 nbBits)
943 {
944     bitD->bitsConsumed += nbBits;
945 }
946 
947 MEM_STATIC size_t BITv06_readBits(BITv06_DStream_t* bitD, U32 nbBits)
948 {
949     size_t const value = BITv06_lookBits(bitD, nbBits);
950     BITv06_skipBits(bitD, nbBits);
951     return value;
952 }
953 
954 /*! BITv06_readBitsFast() :
955 *   unsafe version; only works only if nbBits >= 1 */
956 MEM_STATIC size_t BITv06_readBitsFast(BITv06_DStream_t* bitD, U32 nbBits)
957 {
958     size_t const value = BITv06_lookBitsFast(bitD, nbBits);
959     BITv06_skipBits(bitD, nbBits);
960     return value;
961 }
962 
963 MEM_STATIC BITv06_DStream_status BITv06_reloadDStream(BITv06_DStream_t* bitD)
964 {
965     if (bitD->bitsConsumed > (sizeof(bitD->bitContainer)*8))  /* should never happen */
966         return BITv06_DStream_overflow;
967 
968     if (bitD->ptr >= bitD->start + sizeof(bitD->bitContainer)) {
969         bitD->ptr -= bitD->bitsConsumed >> 3;
970         bitD->bitsConsumed &= 7;
971         bitD->bitContainer = MEM_readLEST(bitD->ptr);
972         return BITv06_DStream_unfinished;
973     }
974     if (bitD->ptr == bitD->start) {
975         if (bitD->bitsConsumed < sizeof(bitD->bitContainer)*8) return BITv06_DStream_endOfBuffer;
976         return BITv06_DStream_completed;
977     }
978     {   U32 nbBytes = bitD->bitsConsumed >> 3;
979         BITv06_DStream_status result = BITv06_DStream_unfinished;
980         if (bitD->ptr - nbBytes < bitD->start) {
981             nbBytes = (U32)(bitD->ptr - bitD->start);  /* ptr > start */
982             result = BITv06_DStream_endOfBuffer;
983         }
984         bitD->ptr -= nbBytes;
985         bitD->bitsConsumed -= nbBytes*8;
986         bitD->bitContainer = MEM_readLEST(bitD->ptr);   /* reminder : srcSize > sizeof(bitD) */
987         return result;
988     }
989 }
990 
991 /*! BITv06_endOfDStream() :
992 *   @return Tells if DStream has exactly reached its end (all bits consumed).
993 */
994 MEM_STATIC unsigned BITv06_endOfDStream(const BITv06_DStream_t* DStream)
995 {
996     return ((DStream->ptr == DStream->start) && (DStream->bitsConsumed == sizeof(DStream->bitContainer)*8));
997 }
998 
999 #if defined (__cplusplus)
1000 }
1001 #endif
1002 
1003 #endif /* BITSTREAM_H_MODULE */
1004 /* ******************************************************************
1005    FSE : Finite State Entropy coder
1006    header file for static linking (only)
1007    Copyright (C) 2013-2015, Yann Collet
1008 
1009    BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
1010 
1011    Redistribution and use in source and binary forms, with or without
1012    modification, are permitted provided that the following conditions are
1013    met:
1014 
1015        * Redistributions of source code must retain the above copyright
1016    notice, this list of conditions and the following disclaimer.
1017        * Redistributions in binary form must reproduce the above
1018    copyright notice, this list of conditions and the following disclaimer
1019    in the documentation and/or other materials provided with the
1020    distribution.
1021 
1022    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
1023    "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
1024    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
1025    A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
1026    OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
1027    SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
1028    LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
1029    DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
1030    THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
1031    (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
1032    OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1033 
1034    You can contact the author at :
1035    - Source repository : https://github.com/Cyan4973/FiniteStateEntropy
1036    - Public forum : https://groups.google.com/forum/#!forum/lz4c
1037 ****************************************************************** */
1038 #ifndef FSEv06_STATIC_H
1039 #define FSEv06_STATIC_H
1040 
1041 #if defined (__cplusplus)
1042 extern "C" {
1043 #endif
1044 
1045 
1046 /* *****************************************
1047 *  Static allocation
1048 *******************************************/
1049 /* FSE buffer bounds */
1050 #define FSEv06_NCOUNTBOUND 512
1051 #define FSEv06_BLOCKBOUND(size) (size + (size>>7))
1052 #define FSEv06_COMPRESSBOUND(size) (FSEv06_NCOUNTBOUND + FSEv06_BLOCKBOUND(size))   /* Macro version, useful for static allocation */
1053 
1054 /* It is possible to statically allocate FSE CTable/DTable as a table of unsigned using below macros */
1055 #define FSEv06_DTABLE_SIZE_U32(maxTableLog)                   (1 + (1<<maxTableLog))
1056 
1057 
1058 /* *****************************************
1059 *  FSE advanced API
1060 *******************************************/
1061 size_t FSEv06_countFast(unsigned* count, unsigned* maxSymbolValuePtr, const void* src, size_t srcSize);
1062 /* same as FSEv06_count(), but blindly trusts that all byte values within src are <= *maxSymbolValuePtr  */
1063 
1064 size_t FSEv06_buildDTable_raw (FSEv06_DTable* dt, unsigned nbBits);
1065 /* build a fake FSEv06_DTable, designed to read an uncompressed bitstream where each symbol uses nbBits */
1066 
1067 size_t FSEv06_buildDTable_rle (FSEv06_DTable* dt, unsigned char symbolValue);
1068 /* build a fake FSEv06_DTable, designed to always generate the same symbolValue */
1069 
1070 
1071 /* *****************************************
1072 *  FSE symbol decompression API
1073 *******************************************/
1074 typedef struct
1075 {
1076     size_t      state;
1077     const void* table;   /* precise table may vary, depending on U16 */
1078 } FSEv06_DState_t;
1079 
1080 
1081 static void     FSEv06_initDState(FSEv06_DState_t* DStatePtr, BITv06_DStream_t* bitD, const FSEv06_DTable* dt);
1082 
1083 static unsigned char FSEv06_decodeSymbol(FSEv06_DState_t* DStatePtr, BITv06_DStream_t* bitD);
1084 
1085 
1086 /* *****************************************
1087 *  FSE unsafe API
1088 *******************************************/
1089 static unsigned char FSEv06_decodeSymbolFast(FSEv06_DState_t* DStatePtr, BITv06_DStream_t* bitD);
1090 /* faster, but works only if nbBits is always >= 1 (otherwise, result will be corrupted) */
1091 
1092 
1093 /* *****************************************
1094 *  Implementation of inlined functions
1095 *******************************************/
1096 
1097 
1098 /* ======    Decompression    ====== */
1099 
1100 typedef struct {
1101     U16 tableLog;
1102     U16 fastMode;
1103 } FSEv06_DTableHeader;   /* sizeof U32 */
1104 
1105 typedef struct
1106 {
1107     unsigned short newState;
1108     unsigned char  symbol;
1109     unsigned char  nbBits;
1110 } FSEv06_decode_t;   /* size == U32 */
1111 
1112 MEM_STATIC void FSEv06_initDState(FSEv06_DState_t* DStatePtr, BITv06_DStream_t* bitD, const FSEv06_DTable* dt)
1113 {
1114     const void* ptr = dt;
1115     const FSEv06_DTableHeader* const DTableH = (const FSEv06_DTableHeader*)ptr;
1116     DStatePtr->state = BITv06_readBits(bitD, DTableH->tableLog);
1117     BITv06_reloadDStream(bitD);
1118     DStatePtr->table = dt + 1;
1119 }
1120 
1121 MEM_STATIC BYTE FSEv06_peekSymbol(const FSEv06_DState_t* DStatePtr)
1122 {
1123     FSEv06_decode_t const DInfo = ((const FSEv06_decode_t*)(DStatePtr->table))[DStatePtr->state];
1124     return DInfo.symbol;
1125 }
1126 
1127 MEM_STATIC void FSEv06_updateState(FSEv06_DState_t* DStatePtr, BITv06_DStream_t* bitD)
1128 {
1129     FSEv06_decode_t const DInfo = ((const FSEv06_decode_t*)(DStatePtr->table))[DStatePtr->state];
1130     U32 const nbBits = DInfo.nbBits;
1131     size_t const lowBits = BITv06_readBits(bitD, nbBits);
1132     DStatePtr->state = DInfo.newState + lowBits;
1133 }
1134 
1135 MEM_STATIC BYTE FSEv06_decodeSymbol(FSEv06_DState_t* DStatePtr, BITv06_DStream_t* bitD)
1136 {
1137     FSEv06_decode_t const DInfo = ((const FSEv06_decode_t*)(DStatePtr->table))[DStatePtr->state];
1138     U32 const nbBits = DInfo.nbBits;
1139     BYTE const symbol = DInfo.symbol;
1140     size_t const lowBits = BITv06_readBits(bitD, nbBits);
1141 
1142     DStatePtr->state = DInfo.newState + lowBits;
1143     return symbol;
1144 }
1145 
1146 /*! FSEv06_decodeSymbolFast() :
1147     unsafe, only works if no symbol has a probability > 50% */
1148 MEM_STATIC BYTE FSEv06_decodeSymbolFast(FSEv06_DState_t* DStatePtr, BITv06_DStream_t* bitD)
1149 {
1150     FSEv06_decode_t const DInfo = ((const FSEv06_decode_t*)(DStatePtr->table))[DStatePtr->state];
1151     U32 const nbBits = DInfo.nbBits;
1152     BYTE const symbol = DInfo.symbol;
1153     size_t const lowBits = BITv06_readBitsFast(bitD, nbBits);
1154 
1155     DStatePtr->state = DInfo.newState + lowBits;
1156     return symbol;
1157 }
1158 
1159 
1160 
1161 #ifndef FSEv06_COMMONDEFS_ONLY
1162 
1163 /* **************************************************************
1164 *  Tuning parameters
1165 ****************************************************************/
1166 /*!MEMORY_USAGE :
1167 *  Memory usage formula : N->2^N Bytes (examples : 10 -> 1KB; 12 -> 4KB ; 16 -> 64KB; 20 -> 1MB; etc.)
1168 *  Increasing memory usage improves compression ratio
1169 *  Reduced memory usage can improve speed, due to cache effect
1170 *  Recommended max value is 14, for 16KB, which nicely fits into Intel x86 L1 cache */
1171 #define FSEv06_MAX_MEMORY_USAGE 14
1172 #define FSEv06_DEFAULT_MEMORY_USAGE 13
1173 
1174 /*!FSEv06_MAX_SYMBOL_VALUE :
1175 *  Maximum symbol value authorized.
1176 *  Required for proper stack allocation */
1177 #define FSEv06_MAX_SYMBOL_VALUE 255
1178 
1179 
1180 /* **************************************************************
1181 *  template functions type & suffix
1182 ****************************************************************/
1183 #define FSEv06_FUNCTION_TYPE BYTE
1184 #define FSEv06_FUNCTION_EXTENSION
1185 #define FSEv06_DECODE_TYPE FSEv06_decode_t
1186 
1187 
1188 #endif   /* !FSEv06_COMMONDEFS_ONLY */
1189 
1190 
1191 /* ***************************************************************
1192 *  Constants
1193 *****************************************************************/
1194 #define FSEv06_MAX_TABLELOG  (FSEv06_MAX_MEMORY_USAGE-2)
1195 #define FSEv06_MAX_TABLESIZE (1U<<FSEv06_MAX_TABLELOG)
1196 #define FSEv06_MAXTABLESIZE_MASK (FSEv06_MAX_TABLESIZE-1)
1197 #define FSEv06_DEFAULT_TABLELOG (FSEv06_DEFAULT_MEMORY_USAGE-2)
1198 #define FSEv06_MIN_TABLELOG 5
1199 
1200 #define FSEv06_TABLELOG_ABSOLUTE_MAX 15
1201 #if FSEv06_MAX_TABLELOG > FSEv06_TABLELOG_ABSOLUTE_MAX
1202 #error "FSEv06_MAX_TABLELOG > FSEv06_TABLELOG_ABSOLUTE_MAX is not supported"
1203 #endif
1204 
1205 #define FSEv06_TABLESTEP(tableSize) ((tableSize>>1) + (tableSize>>3) + 3)
1206 
1207 
1208 #if defined (__cplusplus)
1209 }
1210 #endif
1211 
1212 #endif  /* FSEv06_STATIC_H */
1213 /*
1214    Common functions of New Generation Entropy library
1215    Copyright (C) 2016, Yann Collet.
1216 
1217    BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
1218 
1219    Redistribution and use in source and binary forms, with or without
1220    modification, are permitted provided that the following conditions are
1221    met:
1222 
1223        * Redistributions of source code must retain the above copyright
1224    notice, this list of conditions and the following disclaimer.
1225        * Redistributions in binary form must reproduce the above
1226    copyright notice, this list of conditions and the following disclaimer
1227    in the documentation and/or other materials provided with the
1228    distribution.
1229 
1230    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
1231    "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
1232    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
1233    A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
1234    OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
1235    SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
1236    LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
1237    DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
1238    THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
1239    (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
1240    OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1241 
1242     You can contact the author at :
1243     - FSE+HUF source repository : https://github.com/Cyan4973/FiniteStateEntropy
1244     - Public forum : https://groups.google.com/forum/#!forum/lz4c
1245 *************************************************************************** */
1246 
1247 
1248 /*-****************************************
1249 *  FSE Error Management
1250 ******************************************/
1251 unsigned FSEv06_isError(size_t code) { return ERR_isError(code); }
1252 
1253 const char* FSEv06_getErrorName(size_t code) { return ERR_getErrorName(code); }
1254 
1255 
1256 /* **************************************************************
1257 *  HUF Error Management
1258 ****************************************************************/
1259 static unsigned HUFv06_isError(size_t code) { return ERR_isError(code); }
1260 
1261 
1262 /*-**************************************************************
1263 *  FSE NCount encoding-decoding
1264 ****************************************************************/
1265 static short FSEv06_abs(short a) { return a<0 ? -a : a; }
1266 
1267 size_t FSEv06_readNCount (short* normalizedCounter, unsigned* maxSVPtr, unsigned* tableLogPtr,
1268                  const void* headerBuffer, size_t hbSize)
1269 {
1270     const BYTE* const istart = (const BYTE*) headerBuffer;
1271     const BYTE* const iend = istart + hbSize;
1272     const BYTE* ip = istart;
1273     int nbBits;
1274     int remaining;
1275     int threshold;
1276     U32 bitStream;
1277     int bitCount;
1278     unsigned charnum = 0;
1279     int previous0 = 0;
1280 
1281     if (hbSize < 4) return ERROR(srcSize_wrong);
1282     bitStream = MEM_readLE32(ip);
1283     nbBits = (bitStream & 0xF) + FSEv06_MIN_TABLELOG;   /* extract tableLog */
1284     if (nbBits > FSEv06_TABLELOG_ABSOLUTE_MAX) return ERROR(tableLog_tooLarge);
1285     bitStream >>= 4;
1286     bitCount = 4;
1287     *tableLogPtr = nbBits;
1288     remaining = (1<<nbBits)+1;
1289     threshold = 1<<nbBits;
1290     nbBits++;
1291 
1292     while ((remaining>1) && (charnum<=*maxSVPtr)) {
1293         if (previous0) {
1294             unsigned n0 = charnum;
1295             while ((bitStream & 0xFFFF) == 0xFFFF) {
1296                 n0+=24;
1297                 if (ip < iend-5) {
1298                     ip+=2;
1299                     bitStream = MEM_readLE32(ip) >> bitCount;
1300                 } else {
1301                     bitStream >>= 16;
1302                     bitCount+=16;
1303             }   }
1304             while ((bitStream & 3) == 3) {
1305                 n0+=3;
1306                 bitStream>>=2;
1307                 bitCount+=2;
1308             }
1309             n0 += bitStream & 3;
1310             bitCount += 2;
1311             if (n0 > *maxSVPtr) return ERROR(maxSymbolValue_tooSmall);
1312             while (charnum < n0) normalizedCounter[charnum++] = 0;
1313             if ((ip <= iend-7) || (ip + (bitCount>>3) <= iend-4)) {
1314                 ip += bitCount>>3;
1315                 bitCount &= 7;
1316                 bitStream = MEM_readLE32(ip) >> bitCount;
1317             }
1318             else
1319                 bitStream >>= 2;
1320         }
1321         {   short const max = (short)((2*threshold-1)-remaining);
1322             short count;
1323 
1324             if ((bitStream & (threshold-1)) < (U32)max) {
1325                 count = (short)(bitStream & (threshold-1));
1326                 bitCount   += nbBits-1;
1327             } else {
1328                 count = (short)(bitStream & (2*threshold-1));
1329                 if (count >= threshold) count -= max;
1330                 bitCount   += nbBits;
1331             }
1332 
1333             count--;   /* extra accuracy */
1334             remaining -= FSEv06_abs(count);
1335             normalizedCounter[charnum++] = count;
1336             previous0 = !count;
1337             while (remaining < threshold) {
1338                 nbBits--;
1339                 threshold >>= 1;
1340             }
1341 
1342             if ((ip <= iend-7) || (ip + (bitCount>>3) <= iend-4)) {
1343                 ip += bitCount>>3;
1344                 bitCount &= 7;
1345             } else {
1346                 bitCount -= (int)(8 * (iend - 4 - ip));
1347                 ip = iend - 4;
1348             }
1349             bitStream = MEM_readLE32(ip) >> (bitCount & 31);
1350     }   }   /* while ((remaining>1) && (charnum<=*maxSVPtr)) */
1351     if (remaining != 1) return ERROR(GENERIC);
1352     *maxSVPtr = charnum-1;
1353 
1354     ip += (bitCount+7)>>3;
1355     if ((size_t)(ip-istart) > hbSize) return ERROR(srcSize_wrong);
1356     return ip-istart;
1357 }
1358 /* ******************************************************************
1359    FSE : Finite State Entropy decoder
1360    Copyright (C) 2013-2015, Yann Collet.
1361 
1362    BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
1363 
1364    Redistribution and use in source and binary forms, with or without
1365    modification, are permitted provided that the following conditions are
1366    met:
1367 
1368        * Redistributions of source code must retain the above copyright
1369    notice, this list of conditions and the following disclaimer.
1370        * Redistributions in binary form must reproduce the above
1371    copyright notice, this list of conditions and the following disclaimer
1372    in the documentation and/or other materials provided with the
1373    distribution.
1374 
1375    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
1376    "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
1377    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
1378    A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
1379    OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
1380    SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
1381    LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
1382    DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
1383    THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
1384    (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
1385    OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1386 
1387     You can contact the author at :
1388     - FSE source repository : https://github.com/Cyan4973/FiniteStateEntropy
1389     - Public forum : https://groups.google.com/forum/#!forum/lz4c
1390 ****************************************************************** */
1391 
1392 
1393 /* **************************************************************
1394 *  Compiler specifics
1395 ****************************************************************/
1396 #ifdef _MSC_VER    /* Visual Studio */
1397 #  define FORCE_INLINE static __forceinline
1398 #  include <intrin.h>                    /* For Visual 2005 */
1399 #  pragma warning(disable : 4127)        /* disable: C4127: conditional expression is constant */
1400 #  pragma warning(disable : 4214)        /* disable: C4214: non-int bitfields */
1401 #else
1402 #  if defined (__cplusplus) || defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L   /* C99 */
1403 #    ifdef __GNUC__
1404 #      define FORCE_INLINE static inline __attribute__((always_inline))
1405 #    else
1406 #      define FORCE_INLINE static inline
1407 #    endif
1408 #  else
1409 #    define FORCE_INLINE static
1410 #  endif /* __STDC_VERSION__ */
1411 #endif
1412 
1413 
1414 /* **************************************************************
1415 *  Error Management
1416 ****************************************************************/
1417 #define FSEv06_isError ERR_isError
1418 #define FSEv06_STATIC_ASSERT(c) { enum { FSEv06_static_assert = 1/(int)(!!(c)) }; }   /* use only *after* variable declarations */
1419 
1420 
1421 /* **************************************************************
1422 *  Complex types
1423 ****************************************************************/
1424 typedef U32 DTable_max_t[FSEv06_DTABLE_SIZE_U32(FSEv06_MAX_TABLELOG)];
1425 
1426 
1427 /* **************************************************************
1428 *  Templates
1429 ****************************************************************/
1430 /*
1431   designed to be included
1432   for type-specific functions (template emulation in C)
1433   Objective is to write these functions only once, for improved maintenance
1434 */
1435 
1436 /* safety checks */
1437 #ifndef FSEv06_FUNCTION_EXTENSION
1438 #  error "FSEv06_FUNCTION_EXTENSION must be defined"
1439 #endif
1440 #ifndef FSEv06_FUNCTION_TYPE
1441 #  error "FSEv06_FUNCTION_TYPE must be defined"
1442 #endif
1443 
1444 /* Function names */
1445 #define FSEv06_CAT(X,Y) X##Y
1446 #define FSEv06_FUNCTION_NAME(X,Y) FSEv06_CAT(X,Y)
1447 #define FSEv06_TYPE_NAME(X,Y) FSEv06_CAT(X,Y)
1448 
1449 
1450 /* Function templates */
1451 FSEv06_DTable* FSEv06_createDTable (unsigned tableLog)
1452 {
1453     if (tableLog > FSEv06_TABLELOG_ABSOLUTE_MAX) tableLog = FSEv06_TABLELOG_ABSOLUTE_MAX;
1454     return (FSEv06_DTable*)malloc( FSEv06_DTABLE_SIZE_U32(tableLog) * sizeof (U32) );
1455 }
1456 
1457 void FSEv06_freeDTable (FSEv06_DTable* dt)
1458 {
1459     free(dt);
1460 }
1461 
1462 size_t FSEv06_buildDTable(FSEv06_DTable* dt, const short* normalizedCounter, unsigned maxSymbolValue, unsigned tableLog)
1463 {
1464     void* const tdPtr = dt+1;   /* because *dt is unsigned, 32-bits aligned on 32-bits */
1465     FSEv06_DECODE_TYPE* const tableDecode = (FSEv06_DECODE_TYPE*) (tdPtr);
1466     U16 symbolNext[FSEv06_MAX_SYMBOL_VALUE+1];
1467 
1468     U32 const maxSV1 = maxSymbolValue + 1;
1469     U32 const tableSize = 1 << tableLog;
1470     U32 highThreshold = tableSize-1;
1471 
1472     /* Sanity Checks */
1473     if (maxSymbolValue > FSEv06_MAX_SYMBOL_VALUE) return ERROR(maxSymbolValue_tooLarge);
1474     if (tableLog > FSEv06_MAX_TABLELOG) return ERROR(tableLog_tooLarge);
1475 
1476     /* Init, lay down lowprob symbols */
1477     {   FSEv06_DTableHeader DTableH;
1478         DTableH.tableLog = (U16)tableLog;
1479         DTableH.fastMode = 1;
1480         {   S16 const largeLimit= (S16)(1 << (tableLog-1));
1481             U32 s;
1482             for (s=0; s<maxSV1; s++) {
1483                 if (normalizedCounter[s]==-1) {
1484                     tableDecode[highThreshold--].symbol = (FSEv06_FUNCTION_TYPE)s;
1485                     symbolNext[s] = 1;
1486                 } else {
1487                     if (normalizedCounter[s] >= largeLimit) DTableH.fastMode=0;
1488                     symbolNext[s] = normalizedCounter[s];
1489         }   }   }
1490         memcpy(dt, &DTableH, sizeof(DTableH));
1491     }
1492 
1493     /* Spread symbols */
1494     {   U32 const tableMask = tableSize-1;
1495         U32 const step = FSEv06_TABLESTEP(tableSize);
1496         U32 s, position = 0;
1497         for (s=0; s<maxSV1; s++) {
1498             int i;
1499             for (i=0; i<normalizedCounter[s]; i++) {
1500                 tableDecode[position].symbol = (FSEv06_FUNCTION_TYPE)s;
1501                 position = (position + step) & tableMask;
1502                 while (position > highThreshold) position = (position + step) & tableMask;   /* lowprob area */
1503         }   }
1504 
1505         if (position!=0) return ERROR(GENERIC);   /* position must reach all cells once, otherwise normalizedCounter is incorrect */
1506     }
1507 
1508     /* Build Decoding table */
1509     {   U32 u;
1510         for (u=0; u<tableSize; u++) {
1511             FSEv06_FUNCTION_TYPE const symbol = (FSEv06_FUNCTION_TYPE)(tableDecode[u].symbol);
1512             U16 nextState = symbolNext[symbol]++;
1513             tableDecode[u].nbBits = (BYTE) (tableLog - BITv06_highbit32 ((U32)nextState) );
1514             tableDecode[u].newState = (U16) ( (nextState << tableDecode[u].nbBits) - tableSize);
1515     }   }
1516 
1517     return 0;
1518 }
1519 
1520 
1521 
1522 #ifndef FSEv06_COMMONDEFS_ONLY
1523 
1524 /*-*******************************************************
1525 *  Decompression (Byte symbols)
1526 *********************************************************/
1527 size_t FSEv06_buildDTable_rle (FSEv06_DTable* dt, BYTE symbolValue)
1528 {
1529     void* ptr = dt;
1530     FSEv06_DTableHeader* const DTableH = (FSEv06_DTableHeader*)ptr;
1531     void* dPtr = dt + 1;
1532     FSEv06_decode_t* const cell = (FSEv06_decode_t*)dPtr;
1533 
1534     DTableH->tableLog = 0;
1535     DTableH->fastMode = 0;
1536 
1537     cell->newState = 0;
1538     cell->symbol = symbolValue;
1539     cell->nbBits = 0;
1540 
1541     return 0;
1542 }
1543 
1544 
1545 size_t FSEv06_buildDTable_raw (FSEv06_DTable* dt, unsigned nbBits)
1546 {
1547     void* ptr = dt;
1548     FSEv06_DTableHeader* const DTableH = (FSEv06_DTableHeader*)ptr;
1549     void* dPtr = dt + 1;
1550     FSEv06_decode_t* const dinfo = (FSEv06_decode_t*)dPtr;
1551     const unsigned tableSize = 1 << nbBits;
1552     const unsigned tableMask = tableSize - 1;
1553     const unsigned maxSV1 = tableMask+1;
1554     unsigned s;
1555 
1556     /* Sanity checks */
1557     if (nbBits < 1) return ERROR(GENERIC);         /* min size */
1558 
1559     /* Build Decoding Table */
1560     DTableH->tableLog = (U16)nbBits;
1561     DTableH->fastMode = 1;
1562     for (s=0; s<maxSV1; s++) {
1563         dinfo[s].newState = 0;
1564         dinfo[s].symbol = (BYTE)s;
1565         dinfo[s].nbBits = (BYTE)nbBits;
1566     }
1567 
1568     return 0;
1569 }
1570 
1571 FORCE_INLINE size_t FSEv06_decompress_usingDTable_generic(
1572           void* dst, size_t maxDstSize,
1573     const void* cSrc, size_t cSrcSize,
1574     const FSEv06_DTable* dt, const unsigned fast)
1575 {
1576     BYTE* const ostart = (BYTE*) dst;
1577     BYTE* op = ostart;
1578     BYTE* const omax = op + maxDstSize;
1579     BYTE* const olimit = omax-3;
1580 
1581     BITv06_DStream_t bitD;
1582     FSEv06_DState_t state1;
1583     FSEv06_DState_t state2;
1584 
1585     /* Init */
1586     { size_t const errorCode = BITv06_initDStream(&bitD, cSrc, cSrcSize);   /* replaced last arg by maxCompressed Size */
1587       if (FSEv06_isError(errorCode)) return errorCode; }
1588 
1589     FSEv06_initDState(&state1, &bitD, dt);
1590     FSEv06_initDState(&state2, &bitD, dt);
1591 
1592 #define FSEv06_GETSYMBOL(statePtr) fast ? FSEv06_decodeSymbolFast(statePtr, &bitD) : FSEv06_decodeSymbol(statePtr, &bitD)
1593 
1594     /* 4 symbols per loop */
1595     for ( ; (BITv06_reloadDStream(&bitD)==BITv06_DStream_unfinished) && (op<olimit) ; op+=4) {
1596         op[0] = FSEv06_GETSYMBOL(&state1);
1597 
1598         if (FSEv06_MAX_TABLELOG*2+7 > sizeof(bitD.bitContainer)*8)    /* This test must be static */
1599             BITv06_reloadDStream(&bitD);
1600 
1601         op[1] = FSEv06_GETSYMBOL(&state2);
1602 
1603         if (FSEv06_MAX_TABLELOG*4+7 > sizeof(bitD.bitContainer)*8)    /* This test must be static */
1604             { if (BITv06_reloadDStream(&bitD) > BITv06_DStream_unfinished) { op+=2; break; } }
1605 
1606         op[2] = FSEv06_GETSYMBOL(&state1);
1607 
1608         if (FSEv06_MAX_TABLELOG*2+7 > sizeof(bitD.bitContainer)*8)    /* This test must be static */
1609             BITv06_reloadDStream(&bitD);
1610 
1611         op[3] = FSEv06_GETSYMBOL(&state2);
1612     }
1613 
1614     /* tail */
1615     /* note : BITv06_reloadDStream(&bitD) >= FSEv06_DStream_partiallyFilled; Ends at exactly BITv06_DStream_completed */
1616     while (1) {
1617         if (op>(omax-2)) return ERROR(dstSize_tooSmall);
1618 
1619         *op++ = FSEv06_GETSYMBOL(&state1);
1620 
1621         if (BITv06_reloadDStream(&bitD)==BITv06_DStream_overflow) {
1622             *op++ = FSEv06_GETSYMBOL(&state2);
1623             break;
1624         }
1625 
1626         if (op>(omax-2)) return ERROR(dstSize_tooSmall);
1627 
1628         *op++ = FSEv06_GETSYMBOL(&state2);
1629 
1630         if (BITv06_reloadDStream(&bitD)==BITv06_DStream_overflow) {
1631             *op++ = FSEv06_GETSYMBOL(&state1);
1632             break;
1633     }   }
1634 
1635     return op-ostart;
1636 }
1637 
1638 
1639 size_t FSEv06_decompress_usingDTable(void* dst, size_t originalSize,
1640                             const void* cSrc, size_t cSrcSize,
1641                             const FSEv06_DTable* dt)
1642 {
1643     const void* ptr = dt;
1644     const FSEv06_DTableHeader* DTableH = (const FSEv06_DTableHeader*)ptr;
1645     const U32 fastMode = DTableH->fastMode;
1646 
1647     /* select fast mode (static) */
1648     if (fastMode) return FSEv06_decompress_usingDTable_generic(dst, originalSize, cSrc, cSrcSize, dt, 1);
1649     return FSEv06_decompress_usingDTable_generic(dst, originalSize, cSrc, cSrcSize, dt, 0);
1650 }
1651 
1652 
1653 size_t FSEv06_decompress(void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize)
1654 {
1655     const BYTE* const istart = (const BYTE*)cSrc;
1656     const BYTE* ip = istart;
1657     short counting[FSEv06_MAX_SYMBOL_VALUE+1];
1658     DTable_max_t dt;   /* Static analyzer seems unable to understand this table will be properly initialized later */
1659     unsigned tableLog;
1660     unsigned maxSymbolValue = FSEv06_MAX_SYMBOL_VALUE;
1661 
1662     if (cSrcSize<2) return ERROR(srcSize_wrong);   /* too small input size */
1663 
1664     /* normal FSE decoding mode */
1665     {   size_t const NCountLength = FSEv06_readNCount (counting, &maxSymbolValue, &tableLog, istart, cSrcSize);
1666         if (FSEv06_isError(NCountLength)) return NCountLength;
1667         if (NCountLength >= cSrcSize) return ERROR(srcSize_wrong);   /* too small input size */
1668         ip += NCountLength;
1669         cSrcSize -= NCountLength;
1670     }
1671 
1672     { size_t const errorCode = FSEv06_buildDTable (dt, counting, maxSymbolValue, tableLog);
1673       if (FSEv06_isError(errorCode)) return errorCode; }
1674 
1675     return FSEv06_decompress_usingDTable (dst, maxDstSize, ip, cSrcSize, dt);   /* always return, even if it is an error code */
1676 }
1677 
1678 
1679 
1680 #endif   /* FSEv06_COMMONDEFS_ONLY */
1681 /* ******************************************************************
1682    Huffman coder, part of New Generation Entropy library
1683    header file
1684    Copyright (C) 2013-2016, Yann Collet.
1685 
1686    BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
1687 
1688    Redistribution and use in source and binary forms, with or without
1689    modification, are permitted provided that the following conditions are
1690    met:
1691 
1692        * Redistributions of source code must retain the above copyright
1693    notice, this list of conditions and the following disclaimer.
1694        * Redistributions in binary form must reproduce the above
1695    copyright notice, this list of conditions and the following disclaimer
1696    in the documentation and/or other materials provided with the
1697    distribution.
1698 
1699    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
1700    "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
1701    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
1702    A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
1703    OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
1704    SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
1705    LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
1706    DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
1707    THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
1708    (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
1709    OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1710 
1711    You can contact the author at :
1712    - Source repository : https://github.com/Cyan4973/FiniteStateEntropy
1713 ****************************************************************** */
1714 #ifndef HUFv06_H
1715 #define HUFv06_H
1716 
1717 #if defined (__cplusplus)
1718 extern "C" {
1719 #endif
1720 
1721 
1722 /* ****************************************
1723 *  HUF simple functions
1724 ******************************************/
1725 size_t HUFv06_decompress(void* dst,  size_t dstSize,
1726                 const void* cSrc, size_t cSrcSize);
1727 /*
1728 HUFv06_decompress() :
1729     Decompress HUF data from buffer 'cSrc', of size 'cSrcSize',
1730     into already allocated destination buffer 'dst', of size 'dstSize'.
1731     `dstSize` : must be the **exact** size of original (uncompressed) data.
1732     Note : in contrast with FSE, HUFv06_decompress can regenerate
1733            RLE (cSrcSize==1) and uncompressed (cSrcSize==dstSize) data,
1734            because it knows size to regenerate.
1735     @return : size of regenerated data (== dstSize)
1736               or an error code, which can be tested using HUFv06_isError()
1737 */
1738 
1739 
1740 /* ****************************************
1741 *  Tool functions
1742 ******************************************/
1743 size_t HUFv06_compressBound(size_t size);       /**< maximum compressed size */
1744 
1745 
1746 #if defined (__cplusplus)
1747 }
1748 #endif
1749 
1750 #endif   /* HUFv06_H */
1751 /* ******************************************************************
1752    Huffman codec, part of New Generation Entropy library
1753    header file, for static linking only
1754    Copyright (C) 2013-2016, Yann Collet
1755 
1756    BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
1757 
1758    Redistribution and use in source and binary forms, with or without
1759    modification, are permitted provided that the following conditions are
1760    met:
1761 
1762        * Redistributions of source code must retain the above copyright
1763    notice, this list of conditions and the following disclaimer.
1764        * Redistributions in binary form must reproduce the above
1765    copyright notice, this list of conditions and the following disclaimer
1766    in the documentation and/or other materials provided with the
1767    distribution.
1768 
1769    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
1770    "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
1771    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
1772    A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
1773    OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
1774    SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
1775    LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
1776    DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
1777    THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
1778    (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
1779    OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1780 
1781    You can contact the author at :
1782    - Source repository : https://github.com/Cyan4973/FiniteStateEntropy
1783 ****************************************************************** */
1784 #ifndef HUFv06_STATIC_H
1785 #define HUFv06_STATIC_H
1786 
1787 #if defined (__cplusplus)
1788 extern "C" {
1789 #endif
1790 
1791 
1792 /* ****************************************
1793 *  Static allocation
1794 ******************************************/
1795 /* HUF buffer bounds */
1796 #define HUFv06_CTABLEBOUND 129
1797 #define HUFv06_BLOCKBOUND(size) (size + (size>>8) + 8)   /* only true if incompressible pre-filtered with fast heuristic */
1798 #define HUFv06_COMPRESSBOUND(size) (HUFv06_CTABLEBOUND + HUFv06_BLOCKBOUND(size))   /* Macro version, useful for static allocation */
1799 
1800 /* static allocation of HUF's DTable */
1801 #define HUFv06_DTABLE_SIZE(maxTableLog)   (1 + (1<<maxTableLog))
1802 #define HUFv06_CREATE_STATIC_DTABLEX2(DTable, maxTableLog) \
1803         unsigned short DTable[HUFv06_DTABLE_SIZE(maxTableLog)] = { maxTableLog }
1804 #define HUFv06_CREATE_STATIC_DTABLEX4(DTable, maxTableLog) \
1805         unsigned int DTable[HUFv06_DTABLE_SIZE(maxTableLog)] = { maxTableLog }
1806 #define HUFv06_CREATE_STATIC_DTABLEX6(DTable, maxTableLog) \
1807         unsigned int DTable[HUFv06_DTABLE_SIZE(maxTableLog) * 3 / 2] = { maxTableLog }
1808 
1809 
1810 /* ****************************************
1811 *  Advanced decompression functions
1812 ******************************************/
1813 size_t HUFv06_decompress4X2 (void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize);   /* single-symbol decoder */
1814 size_t HUFv06_decompress4X4 (void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize);   /* double-symbols decoder */
1815 
1816 
1817 
1818 /*!
1819 HUFv06_decompress() does the following:
1820 1. select the decompression algorithm (X2, X4, X6) based on pre-computed heuristics
1821 2. build Huffman table from save, using HUFv06_readDTableXn()
1822 3. decode 1 or 4 segments in parallel using HUFv06_decompressSXn_usingDTable
1823 */
1824 size_t HUFv06_readDTableX2 (unsigned short* DTable, const void* src, size_t srcSize);
1825 size_t HUFv06_readDTableX4 (unsigned* DTable, const void* src, size_t srcSize);
1826 
1827 size_t HUFv06_decompress4X2_usingDTable(void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize, const unsigned short* DTable);
1828 size_t HUFv06_decompress4X4_usingDTable(void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize, const unsigned* DTable);
1829 
1830 
1831 /* single stream variants */
1832 size_t HUFv06_decompress1X2 (void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize);   /* single-symbol decoder */
1833 size_t HUFv06_decompress1X4 (void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize);   /* double-symbol decoder */
1834 
1835 size_t HUFv06_decompress1X2_usingDTable(void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize, const unsigned short* DTable);
1836 size_t HUFv06_decompress1X4_usingDTable(void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize, const unsigned* DTable);
1837 
1838 
1839 
1840 /* **************************************************************
1841 *  Constants
1842 ****************************************************************/
1843 #define HUFv06_ABSOLUTEMAX_TABLELOG  16   /* absolute limit of HUFv06_MAX_TABLELOG. Beyond that value, code does not work */
1844 #define HUFv06_MAX_TABLELOG  12           /* max configured tableLog (for static allocation); can be modified up to HUFv06_ABSOLUTEMAX_TABLELOG */
1845 #define HUFv06_DEFAULT_TABLELOG  HUFv06_MAX_TABLELOG   /* tableLog by default, when not specified */
1846 #define HUFv06_MAX_SYMBOL_VALUE 255
1847 #if (HUFv06_MAX_TABLELOG > HUFv06_ABSOLUTEMAX_TABLELOG)
1848 #  error "HUFv06_MAX_TABLELOG is too large !"
1849 #endif
1850 
1851 
1852 
1853 /*! HUFv06_readStats() :
1854     Read compact Huffman tree, saved by HUFv06_writeCTable().
1855     `huffWeight` is destination buffer.
1856     @return : size read from `src`
1857 */
1858 MEM_STATIC size_t HUFv06_readStats(BYTE* huffWeight, size_t hwSize, U32* rankStats,
1859                             U32* nbSymbolsPtr, U32* tableLogPtr,
1860                             const void* src, size_t srcSize)
1861 {
1862     U32 weightTotal;
1863     const BYTE* ip = (const BYTE*) src;
1864     size_t iSize;
1865     size_t oSize;
1866 
1867     if (!srcSize) return ERROR(srcSize_wrong);
1868     iSize = ip[0];
1869     /* memset(huffWeight, 0, hwSize); */   /* is not necessary, even though some analyzer complain ... */
1870 
1871     if (iSize >= 128)  { /* special header */
1872         if (iSize >= (242)) {  /* RLE */
1873             static U32 l[14] = { 1, 2, 3, 4, 7, 8, 15, 16, 31, 32, 63, 64, 127, 128 };
1874             oSize = l[iSize-242];
1875             memset(huffWeight, 1, hwSize);
1876             iSize = 0;
1877         }
1878         else {   /* Incompressible */
1879             oSize = iSize - 127;
1880             iSize = ((oSize+1)/2);
1881             if (iSize+1 > srcSize) return ERROR(srcSize_wrong);
1882             if (oSize >= hwSize) return ERROR(corruption_detected);
1883             ip += 1;
1884             {   U32 n;
1885                 for (n=0; n<oSize; n+=2) {
1886                     huffWeight[n]   = ip[n/2] >> 4;
1887                     huffWeight[n+1] = ip[n/2] & 15;
1888     }   }   }   }
1889     else  {   /* header compressed with FSE (normal case) */
1890         if (iSize+1 > srcSize) return ERROR(srcSize_wrong);
1891         oSize = FSEv06_decompress(huffWeight, hwSize-1, ip+1, iSize);   /* max (hwSize-1) values decoded, as last one is implied */
1892         if (FSEv06_isError(oSize)) return oSize;
1893     }
1894 
1895     /* collect weight stats */
1896     memset(rankStats, 0, (HUFv06_ABSOLUTEMAX_TABLELOG + 1) * sizeof(U32));
1897     weightTotal = 0;
1898     {   U32 n; for (n=0; n<oSize; n++) {
1899             if (huffWeight[n] >= HUFv06_ABSOLUTEMAX_TABLELOG) return ERROR(corruption_detected);
1900             rankStats[huffWeight[n]]++;
1901             weightTotal += (1 << huffWeight[n]) >> 1;
1902     }   }
1903     if (weightTotal == 0) return ERROR(corruption_detected);
1904 
1905     /* get last non-null symbol weight (implied, total must be 2^n) */
1906     {   U32 const tableLog = BITv06_highbit32(weightTotal) + 1;
1907         if (tableLog > HUFv06_ABSOLUTEMAX_TABLELOG) return ERROR(corruption_detected);
1908         *tableLogPtr = tableLog;
1909         /* determine last weight */
1910         {   U32 const total = 1 << tableLog;
1911             U32 const rest = total - weightTotal;
1912             U32 const verif = 1 << BITv06_highbit32(rest);
1913             U32 const lastWeight = BITv06_highbit32(rest) + 1;
1914             if (verif != rest) return ERROR(corruption_detected);    /* last value must be a clean power of 2 */
1915             huffWeight[oSize] = (BYTE)lastWeight;
1916             rankStats[lastWeight]++;
1917     }   }
1918 
1919     /* check tree construction validity */
1920     if ((rankStats[1] < 2) || (rankStats[1] & 1)) return ERROR(corruption_detected);   /* by construction : at least 2 elts of rank 1, must be even */
1921 
1922     /* results */
1923     *nbSymbolsPtr = (U32)(oSize+1);
1924     return iSize+1;
1925 }
1926 
1927 
1928 
1929 #if defined (__cplusplus)
1930 }
1931 #endif
1932 
1933 #endif /* HUFv06_STATIC_H */
1934 /* ******************************************************************
1935    Huffman decoder, part of New Generation Entropy library
1936    Copyright (C) 2013-2016, Yann Collet.
1937 
1938    BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
1939 
1940    Redistribution and use in source and binary forms, with or without
1941    modification, are permitted provided that the following conditions are
1942    met:
1943 
1944        * Redistributions of source code must retain the above copyright
1945    notice, this list of conditions and the following disclaimer.
1946        * Redistributions in binary form must reproduce the above
1947    copyright notice, this list of conditions and the following disclaimer
1948    in the documentation and/or other materials provided with the
1949    distribution.
1950 
1951    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
1952    "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
1953    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
1954    A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
1955    OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
1956    SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
1957    LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
1958    DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
1959    THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
1960    (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
1961    OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1962 
1963     You can contact the author at :
1964     - FSE+HUF source repository : https://github.com/Cyan4973/FiniteStateEntropy
1965     - Public forum : https://groups.google.com/forum/#!forum/lz4c
1966 ****************************************************************** */
1967 
1968 /* **************************************************************
1969 *  Compiler specifics
1970 ****************************************************************/
1971 #if defined (__cplusplus) || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */)
1972 /* inline is defined */
1973 #elif defined(_MSC_VER)
1974 #  define inline __inline
1975 #else
1976 #  define inline /* disable inline */
1977 #endif
1978 
1979 
1980 #ifdef _MSC_VER    /* Visual Studio */
1981 #  pragma warning(disable : 4127)        /* disable: C4127: conditional expression is constant */
1982 #endif
1983 
1984 
1985 
1986 /* **************************************************************
1987 *  Error Management
1988 ****************************************************************/
1989 #define HUFv06_STATIC_ASSERT(c) { enum { HUFv06_static_assert = 1/(int)(!!(c)) }; }   /* use only *after* variable declarations */
1990 
1991 
1992 
1993 /* *******************************************************
1994 *  HUF : Huffman block decompression
1995 *********************************************************/
1996 typedef struct { BYTE byte; BYTE nbBits; } HUFv06_DEltX2;   /* single-symbol decoding */
1997 
1998 typedef struct { U16 sequence; BYTE nbBits; BYTE length; } HUFv06_DEltX4;  /* double-symbols decoding */
1999 
2000 typedef struct { BYTE symbol; BYTE weight; } sortedSymbol_t;
2001 
2002 
2003 
2004 /*-***************************/
2005 /*  single-symbol decoding   */
2006 /*-***************************/
2007 
2008 size_t HUFv06_readDTableX2 (U16* DTable, const void* src, size_t srcSize)
2009 {
2010     BYTE huffWeight[HUFv06_MAX_SYMBOL_VALUE + 1];
2011     U32 rankVal[HUFv06_ABSOLUTEMAX_TABLELOG + 1];   /* large enough for values from 0 to 16 */
2012     U32 tableLog = 0;
2013     size_t iSize;
2014     U32 nbSymbols = 0;
2015     U32 n;
2016     U32 nextRankStart;
2017     void* const dtPtr = DTable + 1;
2018     HUFv06_DEltX2* const dt = (HUFv06_DEltX2*)dtPtr;
2019 
2020     HUFv06_STATIC_ASSERT(sizeof(HUFv06_DEltX2) == sizeof(U16));   /* if compilation fails here, assertion is false */
2021     /* memset(huffWeight, 0, sizeof(huffWeight)); */   /* is not necessary, even though some analyzer complain ... */
2022 
2023     iSize = HUFv06_readStats(huffWeight, HUFv06_MAX_SYMBOL_VALUE + 1, rankVal, &nbSymbols, &tableLog, src, srcSize);
2024     if (HUFv06_isError(iSize)) return iSize;
2025 
2026     /* check result */
2027     if (tableLog > DTable[0]) return ERROR(tableLog_tooLarge);   /* DTable is too small */
2028     DTable[0] = (U16)tableLog;   /* maybe should separate sizeof allocated DTable, from used size of DTable, in case of re-use */
2029 
2030     /* Prepare ranks */
2031     nextRankStart = 0;
2032     for (n=1; n<tableLog+1; n++) {
2033         U32 current = nextRankStart;
2034         nextRankStart += (rankVal[n] << (n-1));
2035         rankVal[n] = current;
2036     }
2037 
2038     /* fill DTable */
2039     for (n=0; n<nbSymbols; n++) {
2040         const U32 w = huffWeight[n];
2041         const U32 length = (1 << w) >> 1;
2042         U32 i;
2043         HUFv06_DEltX2 D;
2044         D.byte = (BYTE)n; D.nbBits = (BYTE)(tableLog + 1 - w);
2045         for (i = rankVal[w]; i < rankVal[w] + length; i++)
2046             dt[i] = D;
2047         rankVal[w] += length;
2048     }
2049 
2050     return iSize;
2051 }
2052 
2053 
2054 static BYTE HUFv06_decodeSymbolX2(BITv06_DStream_t* Dstream, const HUFv06_DEltX2* dt, const U32 dtLog)
2055 {
2056     const size_t val = BITv06_lookBitsFast(Dstream, dtLog); /* note : dtLog >= 1 */
2057     const BYTE c = dt[val].byte;
2058     BITv06_skipBits(Dstream, dt[val].nbBits);
2059     return c;
2060 }
2061 
2062 #define HUFv06_DECODE_SYMBOLX2_0(ptr, DStreamPtr) \
2063     *ptr++ = HUFv06_decodeSymbolX2(DStreamPtr, dt, dtLog)
2064 
2065 #define HUFv06_DECODE_SYMBOLX2_1(ptr, DStreamPtr) \
2066     if (MEM_64bits() || (HUFv06_MAX_TABLELOG<=12)) \
2067         HUFv06_DECODE_SYMBOLX2_0(ptr, DStreamPtr)
2068 
2069 #define HUFv06_DECODE_SYMBOLX2_2(ptr, DStreamPtr) \
2070     if (MEM_64bits()) \
2071         HUFv06_DECODE_SYMBOLX2_0(ptr, DStreamPtr)
2072 
2073 static inline size_t HUFv06_decodeStreamX2(BYTE* p, BITv06_DStream_t* const bitDPtr, BYTE* const pEnd, const HUFv06_DEltX2* const dt, const U32 dtLog)
2074 {
2075     BYTE* const pStart = p;
2076 
2077     /* up to 4 symbols at a time */
2078     while ((BITv06_reloadDStream(bitDPtr) == BITv06_DStream_unfinished) && (p <= pEnd-4)) {
2079         HUFv06_DECODE_SYMBOLX2_2(p, bitDPtr);
2080         HUFv06_DECODE_SYMBOLX2_1(p, bitDPtr);
2081         HUFv06_DECODE_SYMBOLX2_2(p, bitDPtr);
2082         HUFv06_DECODE_SYMBOLX2_0(p, bitDPtr);
2083     }
2084 
2085     /* closer to the end */
2086     while ((BITv06_reloadDStream(bitDPtr) == BITv06_DStream_unfinished) && (p < pEnd))
2087         HUFv06_DECODE_SYMBOLX2_0(p, bitDPtr);
2088 
2089     /* no more data to retrieve from bitstream, hence no need to reload */
2090     while (p < pEnd)
2091         HUFv06_DECODE_SYMBOLX2_0(p, bitDPtr);
2092 
2093     return pEnd-pStart;
2094 }
2095 
2096 size_t HUFv06_decompress1X2_usingDTable(
2097           void* dst,  size_t dstSize,
2098     const void* cSrc, size_t cSrcSize,
2099     const U16* DTable)
2100 {
2101     BYTE* op = (BYTE*)dst;
2102     BYTE* const oend = op + dstSize;
2103     const U32 dtLog = DTable[0];
2104     const void* dtPtr = DTable;
2105     const HUFv06_DEltX2* const dt = ((const HUFv06_DEltX2*)dtPtr)+1;
2106     BITv06_DStream_t bitD;
2107 
2108     { size_t const errorCode = BITv06_initDStream(&bitD, cSrc, cSrcSize);
2109       if (HUFv06_isError(errorCode)) return errorCode; }
2110 
2111     HUFv06_decodeStreamX2(op, &bitD, oend, dt, dtLog);
2112 
2113     /* check */
2114     if (!BITv06_endOfDStream(&bitD)) return ERROR(corruption_detected);
2115 
2116     return dstSize;
2117 }
2118 
2119 size_t HUFv06_decompress1X2 (void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize)
2120 {
2121     HUFv06_CREATE_STATIC_DTABLEX2(DTable, HUFv06_MAX_TABLELOG);
2122     const BYTE* ip = (const BYTE*) cSrc;
2123 
2124     size_t const errorCode = HUFv06_readDTableX2 (DTable, cSrc, cSrcSize);
2125     if (HUFv06_isError(errorCode)) return errorCode;
2126     if (errorCode >= cSrcSize) return ERROR(srcSize_wrong);
2127     ip += errorCode;
2128     cSrcSize -= errorCode;
2129 
2130     return HUFv06_decompress1X2_usingDTable (dst, dstSize, ip, cSrcSize, DTable);
2131 }
2132 
2133 
2134 size_t HUFv06_decompress4X2_usingDTable(
2135           void* dst,  size_t dstSize,
2136     const void* cSrc, size_t cSrcSize,
2137     const U16* DTable)
2138 {
2139     /* Check */
2140     if (cSrcSize < 10) return ERROR(corruption_detected);  /* strict minimum : jump table + 1 byte per stream */
2141 
2142     {   const BYTE* const istart = (const BYTE*) cSrc;
2143         BYTE* const ostart = (BYTE*) dst;
2144         BYTE* const oend = ostart + dstSize;
2145         const void* const dtPtr = DTable;
2146         const HUFv06_DEltX2* const dt = ((const HUFv06_DEltX2*)dtPtr) +1;
2147         const U32 dtLog = DTable[0];
2148         size_t errorCode;
2149 
2150         /* Init */
2151         BITv06_DStream_t bitD1;
2152         BITv06_DStream_t bitD2;
2153         BITv06_DStream_t bitD3;
2154         BITv06_DStream_t bitD4;
2155         const size_t length1 = MEM_readLE16(istart);
2156         const size_t length2 = MEM_readLE16(istart+2);
2157         const size_t length3 = MEM_readLE16(istart+4);
2158         size_t length4;
2159         const BYTE* const istart1 = istart + 6;  /* jumpTable */
2160         const BYTE* const istart2 = istart1 + length1;
2161         const BYTE* const istart3 = istart2 + length2;
2162         const BYTE* const istart4 = istart3 + length3;
2163         const size_t segmentSize = (dstSize+3) / 4;
2164         BYTE* const opStart2 = ostart + segmentSize;
2165         BYTE* const opStart3 = opStart2 + segmentSize;
2166         BYTE* const opStart4 = opStart3 + segmentSize;
2167         BYTE* op1 = ostart;
2168         BYTE* op2 = opStart2;
2169         BYTE* op3 = opStart3;
2170         BYTE* op4 = opStart4;
2171         U32 endSignal;
2172 
2173         length4 = cSrcSize - (length1 + length2 + length3 + 6);
2174         if (length4 > cSrcSize) return ERROR(corruption_detected);   /* overflow */
2175         errorCode = BITv06_initDStream(&bitD1, istart1, length1);
2176         if (HUFv06_isError(errorCode)) return errorCode;
2177         errorCode = BITv06_initDStream(&bitD2, istart2, length2);
2178         if (HUFv06_isError(errorCode)) return errorCode;
2179         errorCode = BITv06_initDStream(&bitD3, istart3, length3);
2180         if (HUFv06_isError(errorCode)) return errorCode;
2181         errorCode = BITv06_initDStream(&bitD4, istart4, length4);
2182         if (HUFv06_isError(errorCode)) return errorCode;
2183 
2184         /* 16-32 symbols per loop (4-8 symbols per stream) */
2185         endSignal = BITv06_reloadDStream(&bitD1) | BITv06_reloadDStream(&bitD2) | BITv06_reloadDStream(&bitD3) | BITv06_reloadDStream(&bitD4);
2186         for ( ; (endSignal==BITv06_DStream_unfinished) && (op4<(oend-7)) ; ) {
2187             HUFv06_DECODE_SYMBOLX2_2(op1, &bitD1);
2188             HUFv06_DECODE_SYMBOLX2_2(op2, &bitD2);
2189             HUFv06_DECODE_SYMBOLX2_2(op3, &bitD3);
2190             HUFv06_DECODE_SYMBOLX2_2(op4, &bitD4);
2191             HUFv06_DECODE_SYMBOLX2_1(op1, &bitD1);
2192             HUFv06_DECODE_SYMBOLX2_1(op2, &bitD2);
2193             HUFv06_DECODE_SYMBOLX2_1(op3, &bitD3);
2194             HUFv06_DECODE_SYMBOLX2_1(op4, &bitD4);
2195             HUFv06_DECODE_SYMBOLX2_2(op1, &bitD1);
2196             HUFv06_DECODE_SYMBOLX2_2(op2, &bitD2);
2197             HUFv06_DECODE_SYMBOLX2_2(op3, &bitD3);
2198             HUFv06_DECODE_SYMBOLX2_2(op4, &bitD4);
2199             HUFv06_DECODE_SYMBOLX2_0(op1, &bitD1);
2200             HUFv06_DECODE_SYMBOLX2_0(op2, &bitD2);
2201             HUFv06_DECODE_SYMBOLX2_0(op3, &bitD3);
2202             HUFv06_DECODE_SYMBOLX2_0(op4, &bitD4);
2203             endSignal = BITv06_reloadDStream(&bitD1) | BITv06_reloadDStream(&bitD2) | BITv06_reloadDStream(&bitD3) | BITv06_reloadDStream(&bitD4);
2204         }
2205 
2206         /* check corruption */
2207         if (op1 > opStart2) return ERROR(corruption_detected);
2208         if (op2 > opStart3) return ERROR(corruption_detected);
2209         if (op3 > opStart4) return ERROR(corruption_detected);
2210         /* note : op4 supposed already verified within main loop */
2211 
2212         /* finish bitStreams one by one */
2213         HUFv06_decodeStreamX2(op1, &bitD1, opStart2, dt, dtLog);
2214         HUFv06_decodeStreamX2(op2, &bitD2, opStart3, dt, dtLog);
2215         HUFv06_decodeStreamX2(op3, &bitD3, opStart4, dt, dtLog);
2216         HUFv06_decodeStreamX2(op4, &bitD4, oend,     dt, dtLog);
2217 
2218         /* check */
2219         endSignal = BITv06_endOfDStream(&bitD1) & BITv06_endOfDStream(&bitD2) & BITv06_endOfDStream(&bitD3) & BITv06_endOfDStream(&bitD4);
2220         if (!endSignal) return ERROR(corruption_detected);
2221 
2222         /* decoded size */
2223         return dstSize;
2224     }
2225 }
2226 
2227 
2228 size_t HUFv06_decompress4X2 (void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize)
2229 {
2230     HUFv06_CREATE_STATIC_DTABLEX2(DTable, HUFv06_MAX_TABLELOG);
2231     const BYTE* ip = (const BYTE*) cSrc;
2232 
2233     size_t const errorCode = HUFv06_readDTableX2 (DTable, cSrc, cSrcSize);
2234     if (HUFv06_isError(errorCode)) return errorCode;
2235     if (errorCode >= cSrcSize) return ERROR(srcSize_wrong);
2236     ip += errorCode;
2237     cSrcSize -= errorCode;
2238 
2239     return HUFv06_decompress4X2_usingDTable (dst, dstSize, ip, cSrcSize, DTable);
2240 }
2241 
2242 
2243 /* *************************/
2244 /* double-symbols decoding */
2245 /* *************************/
2246 
2247 static void HUFv06_fillDTableX4Level2(HUFv06_DEltX4* DTable, U32 sizeLog, const U32 consumed,
2248                            const U32* rankValOrigin, const int minWeight,
2249                            const sortedSymbol_t* sortedSymbols, const U32 sortedListSize,
2250                            U32 nbBitsBaseline, U16 baseSeq)
2251 {
2252     HUFv06_DEltX4 DElt;
2253     U32 rankVal[HUFv06_ABSOLUTEMAX_TABLELOG + 1];
2254 
2255     /* get pre-calculated rankVal */
2256     memcpy(rankVal, rankValOrigin, sizeof(rankVal));
2257 
2258     /* fill skipped values */
2259     if (minWeight>1) {
2260         U32 i, skipSize = rankVal[minWeight];
2261         MEM_writeLE16(&(DElt.sequence), baseSeq);
2262         DElt.nbBits   = (BYTE)(consumed);
2263         DElt.length   = 1;
2264         for (i = 0; i < skipSize; i++)
2265             DTable[i] = DElt;
2266     }
2267 
2268     /* fill DTable */
2269     { U32 s; for (s=0; s<sortedListSize; s++) {   /* note : sortedSymbols already skipped */
2270         const U32 symbol = sortedSymbols[s].symbol;
2271         const U32 weight = sortedSymbols[s].weight;
2272         const U32 nbBits = nbBitsBaseline - weight;
2273         const U32 length = 1 << (sizeLog-nbBits);
2274         const U32 start = rankVal[weight];
2275         U32 i = start;
2276         const U32 end = start + length;
2277 
2278         MEM_writeLE16(&(DElt.sequence), (U16)(baseSeq + (symbol << 8)));
2279         DElt.nbBits = (BYTE)(nbBits + consumed);
2280         DElt.length = 2;
2281         do { DTable[i++] = DElt; } while (i<end);   /* since length >= 1 */
2282 
2283         rankVal[weight] += length;
2284     }}
2285 }
2286 
2287 typedef U32 rankVal_t[HUFv06_ABSOLUTEMAX_TABLELOG][HUFv06_ABSOLUTEMAX_TABLELOG + 1];
2288 
2289 static void HUFv06_fillDTableX4(HUFv06_DEltX4* DTable, const U32 targetLog,
2290                            const sortedSymbol_t* sortedList, const U32 sortedListSize,
2291                            const U32* rankStart, rankVal_t rankValOrigin, const U32 maxWeight,
2292                            const U32 nbBitsBaseline)
2293 {
2294     U32 rankVal[HUFv06_ABSOLUTEMAX_TABLELOG + 1];
2295     const int scaleLog = nbBitsBaseline - targetLog;   /* note : targetLog >= srcLog, hence scaleLog <= 1 */
2296     const U32 minBits  = nbBitsBaseline - maxWeight;
2297     U32 s;
2298 
2299     memcpy(rankVal, rankValOrigin, sizeof(rankVal));
2300 
2301     /* fill DTable */
2302     for (s=0; s<sortedListSize; s++) {
2303         const U16 symbol = sortedList[s].symbol;
2304         const U32 weight = sortedList[s].weight;
2305         const U32 nbBits = nbBitsBaseline - weight;
2306         const U32 start = rankVal[weight];
2307         const U32 length = 1 << (targetLog-nbBits);
2308 
2309         if (targetLog-nbBits >= minBits) {   /* enough room for a second symbol */
2310             U32 sortedRank;
2311             int minWeight = nbBits + scaleLog;
2312             if (minWeight < 1) minWeight = 1;
2313             sortedRank = rankStart[minWeight];
2314             HUFv06_fillDTableX4Level2(DTable+start, targetLog-nbBits, nbBits,
2315                            rankValOrigin[nbBits], minWeight,
2316                            sortedList+sortedRank, sortedListSize-sortedRank,
2317                            nbBitsBaseline, symbol);
2318         } else {
2319             HUFv06_DEltX4 DElt;
2320             MEM_writeLE16(&(DElt.sequence), symbol);
2321             DElt.nbBits = (BYTE)(nbBits);
2322             DElt.length = 1;
2323             {   U32 u;
2324                 const U32 end = start + length;
2325                 for (u = start; u < end; u++) DTable[u] = DElt;
2326         }   }
2327         rankVal[weight] += length;
2328     }
2329 }
2330 
2331 size_t HUFv06_readDTableX4 (U32* DTable, const void* src, size_t srcSize)
2332 {
2333     BYTE weightList[HUFv06_MAX_SYMBOL_VALUE + 1];
2334     sortedSymbol_t sortedSymbol[HUFv06_MAX_SYMBOL_VALUE + 1];
2335     U32 rankStats[HUFv06_ABSOLUTEMAX_TABLELOG + 1] = { 0 };
2336     U32 rankStart0[HUFv06_ABSOLUTEMAX_TABLELOG + 2] = { 0 };
2337     U32* const rankStart = rankStart0+1;
2338     rankVal_t rankVal;
2339     U32 tableLog, maxW, sizeOfSort, nbSymbols;
2340     const U32 memLog = DTable[0];
2341     size_t iSize;
2342     void* dtPtr = DTable;
2343     HUFv06_DEltX4* const dt = ((HUFv06_DEltX4*)dtPtr) + 1;
2344 
2345     HUFv06_STATIC_ASSERT(sizeof(HUFv06_DEltX4) == sizeof(U32));   /* if compilation fails here, assertion is false */
2346     if (memLog > HUFv06_ABSOLUTEMAX_TABLELOG) return ERROR(tableLog_tooLarge);
2347     /* memset(weightList, 0, sizeof(weightList)); */   /* is not necessary, even though some analyzer complain ... */
2348 
2349     iSize = HUFv06_readStats(weightList, HUFv06_MAX_SYMBOL_VALUE + 1, rankStats, &nbSymbols, &tableLog, src, srcSize);
2350     if (HUFv06_isError(iSize)) return iSize;
2351 
2352     /* check result */
2353     if (tableLog > memLog) return ERROR(tableLog_tooLarge);   /* DTable can't fit code depth */
2354 
2355     /* find maxWeight */
2356     for (maxW = tableLog; rankStats[maxW]==0; maxW--) {}  /* necessarily finds a solution before 0 */
2357 
2358     /* Get start index of each weight */
2359     {   U32 w, nextRankStart = 0;
2360         for (w=1; w<maxW+1; w++) {
2361             U32 current = nextRankStart;
2362             nextRankStart += rankStats[w];
2363             rankStart[w] = current;
2364         }
2365         rankStart[0] = nextRankStart;   /* put all 0w symbols at the end of sorted list*/
2366         sizeOfSort = nextRankStart;
2367     }
2368 
2369     /* sort symbols by weight */
2370     {   U32 s;
2371         for (s=0; s<nbSymbols; s++) {
2372             U32 const w = weightList[s];
2373             U32 const r = rankStart[w]++;
2374             sortedSymbol[r].symbol = (BYTE)s;
2375             sortedSymbol[r].weight = (BYTE)w;
2376         }
2377         rankStart[0] = 0;   /* forget 0w symbols; this is beginning of weight(1) */
2378     }
2379 
2380     /* Build rankVal */
2381     {   U32* const rankVal0 = rankVal[0];
2382         {   int const rescale = (memLog-tableLog) - 1;   /* tableLog <= memLog */
2383             U32 nextRankVal = 0;
2384             U32 w;
2385             for (w=1; w<maxW+1; w++) {
2386                 U32 current = nextRankVal;
2387                 nextRankVal += rankStats[w] << (w+rescale);
2388                 rankVal0[w] = current;
2389         }   }
2390         {   U32 const minBits = tableLog+1 - maxW;
2391             U32 consumed;
2392             for (consumed = minBits; consumed < memLog - minBits + 1; consumed++) {
2393                 U32* const rankValPtr = rankVal[consumed];
2394                 U32 w;
2395                 for (w = 1; w < maxW+1; w++) {
2396                     rankValPtr[w] = rankVal0[w] >> consumed;
2397     }   }   }   }
2398 
2399     HUFv06_fillDTableX4(dt, memLog,
2400                    sortedSymbol, sizeOfSort,
2401                    rankStart0, rankVal, maxW,
2402                    tableLog+1);
2403 
2404     return iSize;
2405 }
2406 
2407 
2408 static U32 HUFv06_decodeSymbolX4(void* op, BITv06_DStream_t* DStream, const HUFv06_DEltX4* dt, const U32 dtLog)
2409 {
2410     const size_t val = BITv06_lookBitsFast(DStream, dtLog);   /* note : dtLog >= 1 */
2411     memcpy(op, dt+val, 2);
2412     BITv06_skipBits(DStream, dt[val].nbBits);
2413     return dt[val].length;
2414 }
2415 
2416 static U32 HUFv06_decodeLastSymbolX4(void* op, BITv06_DStream_t* DStream, const HUFv06_DEltX4* dt, const U32 dtLog)
2417 {
2418     const size_t val = BITv06_lookBitsFast(DStream, dtLog);   /* note : dtLog >= 1 */
2419     memcpy(op, dt+val, 1);
2420     if (dt[val].length==1) BITv06_skipBits(DStream, dt[val].nbBits);
2421     else {
2422         if (DStream->bitsConsumed < (sizeof(DStream->bitContainer)*8)) {
2423             BITv06_skipBits(DStream, dt[val].nbBits);
2424             if (DStream->bitsConsumed > (sizeof(DStream->bitContainer)*8))
2425                 DStream->bitsConsumed = (sizeof(DStream->bitContainer)*8);   /* ugly hack; works only because it's the last symbol. Note : can't easily extract nbBits from just this symbol */
2426     }   }
2427     return 1;
2428 }
2429 
2430 
2431 #define HUFv06_DECODE_SYMBOLX4_0(ptr, DStreamPtr) \
2432     ptr += HUFv06_decodeSymbolX4(ptr, DStreamPtr, dt, dtLog)
2433 
2434 #define HUFv06_DECODE_SYMBOLX4_1(ptr, DStreamPtr) \
2435     if (MEM_64bits() || (HUFv06_MAX_TABLELOG<=12)) \
2436         ptr += HUFv06_decodeSymbolX4(ptr, DStreamPtr, dt, dtLog)
2437 
2438 #define HUFv06_DECODE_SYMBOLX4_2(ptr, DStreamPtr) \
2439     if (MEM_64bits()) \
2440         ptr += HUFv06_decodeSymbolX4(ptr, DStreamPtr, dt, dtLog)
2441 
2442 static inline size_t HUFv06_decodeStreamX4(BYTE* p, BITv06_DStream_t* bitDPtr, BYTE* const pEnd, const HUFv06_DEltX4* const dt, const U32 dtLog)
2443 {
2444     BYTE* const pStart = p;
2445 
2446     /* up to 8 symbols at a time */
2447     while ((BITv06_reloadDStream(bitDPtr) == BITv06_DStream_unfinished) && (p < pEnd-7)) {
2448         HUFv06_DECODE_SYMBOLX4_2(p, bitDPtr);
2449         HUFv06_DECODE_SYMBOLX4_1(p, bitDPtr);
2450         HUFv06_DECODE_SYMBOLX4_2(p, bitDPtr);
2451         HUFv06_DECODE_SYMBOLX4_0(p, bitDPtr);
2452     }
2453 
2454     /* closer to the end */
2455     while ((BITv06_reloadDStream(bitDPtr) == BITv06_DStream_unfinished) && (p <= pEnd-2))
2456         HUFv06_DECODE_SYMBOLX4_0(p, bitDPtr);
2457 
2458     while (p <= pEnd-2)
2459         HUFv06_DECODE_SYMBOLX4_0(p, bitDPtr);   /* no need to reload : reached the end of DStream */
2460 
2461     if (p < pEnd)
2462         p += HUFv06_decodeLastSymbolX4(p, bitDPtr, dt, dtLog);
2463 
2464     return p-pStart;
2465 }
2466 
2467 
2468 size_t HUFv06_decompress1X4_usingDTable(
2469           void* dst,  size_t dstSize,
2470     const void* cSrc, size_t cSrcSize,
2471     const U32* DTable)
2472 {
2473     const BYTE* const istart = (const BYTE*) cSrc;
2474     BYTE* const ostart = (BYTE*) dst;
2475     BYTE* const oend = ostart + dstSize;
2476 
2477     const U32 dtLog = DTable[0];
2478     const void* const dtPtr = DTable;
2479     const HUFv06_DEltX4* const dt = ((const HUFv06_DEltX4*)dtPtr) +1;
2480 
2481     /* Init */
2482     BITv06_DStream_t bitD;
2483     { size_t const errorCode = BITv06_initDStream(&bitD, istart, cSrcSize);
2484       if (HUFv06_isError(errorCode)) return errorCode; }
2485 
2486     /* decode */
2487     HUFv06_decodeStreamX4(ostart, &bitD, oend, dt, dtLog);
2488 
2489     /* check */
2490     if (!BITv06_endOfDStream(&bitD)) return ERROR(corruption_detected);
2491 
2492     /* decoded size */
2493     return dstSize;
2494 }
2495 
2496 size_t HUFv06_decompress1X4 (void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize)
2497 {
2498     HUFv06_CREATE_STATIC_DTABLEX4(DTable, HUFv06_MAX_TABLELOG);
2499     const BYTE* ip = (const BYTE*) cSrc;
2500 
2501     size_t const hSize = HUFv06_readDTableX4 (DTable, cSrc, cSrcSize);
2502     if (HUFv06_isError(hSize)) return hSize;
2503     if (hSize >= cSrcSize) return ERROR(srcSize_wrong);
2504     ip += hSize;
2505     cSrcSize -= hSize;
2506 
2507     return HUFv06_decompress1X4_usingDTable (dst, dstSize, ip, cSrcSize, DTable);
2508 }
2509 
2510 size_t HUFv06_decompress4X4_usingDTable(
2511           void* dst,  size_t dstSize,
2512     const void* cSrc, size_t cSrcSize,
2513     const U32* DTable)
2514 {
2515     if (cSrcSize < 10) return ERROR(corruption_detected);   /* strict minimum : jump table + 1 byte per stream */
2516 
2517     {   const BYTE* const istart = (const BYTE*) cSrc;
2518         BYTE* const ostart = (BYTE*) dst;
2519         BYTE* const oend = ostart + dstSize;
2520         const void* const dtPtr = DTable;
2521         const HUFv06_DEltX4* const dt = ((const HUFv06_DEltX4*)dtPtr) +1;
2522         const U32 dtLog = DTable[0];
2523         size_t errorCode;
2524 
2525         /* Init */
2526         BITv06_DStream_t bitD1;
2527         BITv06_DStream_t bitD2;
2528         BITv06_DStream_t bitD3;
2529         BITv06_DStream_t bitD4;
2530         const size_t length1 = MEM_readLE16(istart);
2531         const size_t length2 = MEM_readLE16(istart+2);
2532         const size_t length3 = MEM_readLE16(istart+4);
2533         size_t length4;
2534         const BYTE* const istart1 = istart + 6;  /* jumpTable */
2535         const BYTE* const istart2 = istart1 + length1;
2536         const BYTE* const istart3 = istart2 + length2;
2537         const BYTE* const istart4 = istart3 + length3;
2538         const size_t segmentSize = (dstSize+3) / 4;
2539         BYTE* const opStart2 = ostart + segmentSize;
2540         BYTE* const opStart3 = opStart2 + segmentSize;
2541         BYTE* const opStart4 = opStart3 + segmentSize;
2542         BYTE* op1 = ostart;
2543         BYTE* op2 = opStart2;
2544         BYTE* op3 = opStart3;
2545         BYTE* op4 = opStart4;
2546         U32 endSignal;
2547 
2548         length4 = cSrcSize - (length1 + length2 + length3 + 6);
2549         if (length4 > cSrcSize) return ERROR(corruption_detected);   /* overflow */
2550         errorCode = BITv06_initDStream(&bitD1, istart1, length1);
2551         if (HUFv06_isError(errorCode)) return errorCode;
2552         errorCode = BITv06_initDStream(&bitD2, istart2, length2);
2553         if (HUFv06_isError(errorCode)) return errorCode;
2554         errorCode = BITv06_initDStream(&bitD3, istart3, length3);
2555         if (HUFv06_isError(errorCode)) return errorCode;
2556         errorCode = BITv06_initDStream(&bitD4, istart4, length4);
2557         if (HUFv06_isError(errorCode)) return errorCode;
2558 
2559         /* 16-32 symbols per loop (4-8 symbols per stream) */
2560         endSignal = BITv06_reloadDStream(&bitD1) | BITv06_reloadDStream(&bitD2) | BITv06_reloadDStream(&bitD3) | BITv06_reloadDStream(&bitD4);
2561         for ( ; (endSignal==BITv06_DStream_unfinished) && (op4<(oend-7)) ; ) {
2562             HUFv06_DECODE_SYMBOLX4_2(op1, &bitD1);
2563             HUFv06_DECODE_SYMBOLX4_2(op2, &bitD2);
2564             HUFv06_DECODE_SYMBOLX4_2(op3, &bitD3);
2565             HUFv06_DECODE_SYMBOLX4_2(op4, &bitD4);
2566             HUFv06_DECODE_SYMBOLX4_1(op1, &bitD1);
2567             HUFv06_DECODE_SYMBOLX4_1(op2, &bitD2);
2568             HUFv06_DECODE_SYMBOLX4_1(op3, &bitD3);
2569             HUFv06_DECODE_SYMBOLX4_1(op4, &bitD4);
2570             HUFv06_DECODE_SYMBOLX4_2(op1, &bitD1);
2571             HUFv06_DECODE_SYMBOLX4_2(op2, &bitD2);
2572             HUFv06_DECODE_SYMBOLX4_2(op3, &bitD3);
2573             HUFv06_DECODE_SYMBOLX4_2(op4, &bitD4);
2574             HUFv06_DECODE_SYMBOLX4_0(op1, &bitD1);
2575             HUFv06_DECODE_SYMBOLX4_0(op2, &bitD2);
2576             HUFv06_DECODE_SYMBOLX4_0(op3, &bitD3);
2577             HUFv06_DECODE_SYMBOLX4_0(op4, &bitD4);
2578 
2579             endSignal = BITv06_reloadDStream(&bitD1) | BITv06_reloadDStream(&bitD2) | BITv06_reloadDStream(&bitD3) | BITv06_reloadDStream(&bitD4);
2580         }
2581 
2582         /* check corruption */
2583         if (op1 > opStart2) return ERROR(corruption_detected);
2584         if (op2 > opStart3) return ERROR(corruption_detected);
2585         if (op3 > opStart4) return ERROR(corruption_detected);
2586         /* note : op4 supposed already verified within main loop */
2587 
2588         /* finish bitStreams one by one */
2589         HUFv06_decodeStreamX4(op1, &bitD1, opStart2, dt, dtLog);
2590         HUFv06_decodeStreamX4(op2, &bitD2, opStart3, dt, dtLog);
2591         HUFv06_decodeStreamX4(op3, &bitD3, opStart4, dt, dtLog);
2592         HUFv06_decodeStreamX4(op4, &bitD4, oend,     dt, dtLog);
2593 
2594         /* check */
2595         endSignal = BITv06_endOfDStream(&bitD1) & BITv06_endOfDStream(&bitD2) & BITv06_endOfDStream(&bitD3) & BITv06_endOfDStream(&bitD4);
2596         if (!endSignal) return ERROR(corruption_detected);
2597 
2598         /* decoded size */
2599         return dstSize;
2600     }
2601 }
2602 
2603 
2604 size_t HUFv06_decompress4X4 (void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize)
2605 {
2606     HUFv06_CREATE_STATIC_DTABLEX4(DTable, HUFv06_MAX_TABLELOG);
2607     const BYTE* ip = (const BYTE*) cSrc;
2608 
2609     size_t hSize = HUFv06_readDTableX4 (DTable, cSrc, cSrcSize);
2610     if (HUFv06_isError(hSize)) return hSize;
2611     if (hSize >= cSrcSize) return ERROR(srcSize_wrong);
2612     ip += hSize;
2613     cSrcSize -= hSize;
2614 
2615     return HUFv06_decompress4X4_usingDTable (dst, dstSize, ip, cSrcSize, DTable);
2616 }
2617 
2618 
2619 
2620 
2621 /* ********************************/
2622 /* Generic decompression selector */
2623 /* ********************************/
2624 
2625 typedef struct { U32 tableTime; U32 decode256Time; } algo_time_t;
2626 static const algo_time_t algoTime[16 /* Quantization */][3 /* single, double, quad */] =
2627 {
2628     /* single, double, quad */
2629     {{0,0}, {1,1}, {2,2}},  /* Q==0 : impossible */
2630     {{0,0}, {1,1}, {2,2}},  /* Q==1 : impossible */
2631     {{  38,130}, {1313, 74}, {2151, 38}},   /* Q == 2 : 12-18% */
2632     {{ 448,128}, {1353, 74}, {2238, 41}},   /* Q == 3 : 18-25% */
2633     {{ 556,128}, {1353, 74}, {2238, 47}},   /* Q == 4 : 25-32% */
2634     {{ 714,128}, {1418, 74}, {2436, 53}},   /* Q == 5 : 32-38% */
2635     {{ 883,128}, {1437, 74}, {2464, 61}},   /* Q == 6 : 38-44% */
2636     {{ 897,128}, {1515, 75}, {2622, 68}},   /* Q == 7 : 44-50% */
2637     {{ 926,128}, {1613, 75}, {2730, 75}},   /* Q == 8 : 50-56% */
2638     {{ 947,128}, {1729, 77}, {3359, 77}},   /* Q == 9 : 56-62% */
2639     {{1107,128}, {2083, 81}, {4006, 84}},   /* Q ==10 : 62-69% */
2640     {{1177,128}, {2379, 87}, {4785, 88}},   /* Q ==11 : 69-75% */
2641     {{1242,128}, {2415, 93}, {5155, 84}},   /* Q ==12 : 75-81% */
2642     {{1349,128}, {2644,106}, {5260,106}},   /* Q ==13 : 81-87% */
2643     {{1455,128}, {2422,124}, {4174,124}},   /* Q ==14 : 87-93% */
2644     {{ 722,128}, {1891,145}, {1936,146}},   /* Q ==15 : 93-99% */
2645 };
2646 
2647 typedef size_t (*decompressionAlgo)(void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize);
2648 
2649 size_t HUFv06_decompress (void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize)
2650 {
2651     static const decompressionAlgo decompress[3] = { HUFv06_decompress4X2, HUFv06_decompress4X4, NULL };
2652     U32 Dtime[3];   /* decompression time estimation */
2653 
2654     /* validation checks */
2655     if (dstSize == 0) return ERROR(dstSize_tooSmall);
2656     if (cSrcSize > dstSize) return ERROR(corruption_detected);   /* invalid */
2657     if (cSrcSize == dstSize) { memcpy(dst, cSrc, dstSize); return dstSize; }   /* not compressed */
2658     if (cSrcSize == 1) { memset(dst, *(const BYTE*)cSrc, dstSize); return dstSize; }   /* RLE */
2659 
2660     /* decoder timing evaluation */
2661     {   U32 const Q = (U32)(cSrcSize * 16 / dstSize);   /* Q < 16 since dstSize > cSrcSize */
2662         U32 const D256 = (U32)(dstSize >> 8);
2663         U32 n; for (n=0; n<3; n++)
2664             Dtime[n] = algoTime[Q][n].tableTime + (algoTime[Q][n].decode256Time * D256);
2665     }
2666 
2667     Dtime[1] += Dtime[1] >> 4; Dtime[2] += Dtime[2] >> 3; /* advantage to algorithms using less memory, for cache eviction */
2668 
2669     {   U32 algoNb = 0;
2670         if (Dtime[1] < Dtime[0]) algoNb = 1;
2671         /* if (Dtime[2] < Dtime[algoNb]) algoNb = 2; */   /* current speed of HUFv06_decompress4X6 is not good */
2672         return decompress[algoNb](dst, dstSize, cSrc, cSrcSize);
2673     }
2674 
2675     /* return HUFv06_decompress4X2(dst, dstSize, cSrc, cSrcSize); */   /* multi-streams single-symbol decoding */
2676     /* return HUFv06_decompress4X4(dst, dstSize, cSrc, cSrcSize); */   /* multi-streams double-symbols decoding */
2677     /* return HUFv06_decompress4X6(dst, dstSize, cSrc, cSrcSize); */   /* multi-streams quad-symbols decoding */
2678 }
2679 /*
2680     Common functions of Zstd compression library
2681     Copyright (C) 2015-2016, Yann Collet.
2682 
2683     BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
2684 
2685     Redistribution and use in source and binary forms, with or without
2686     modification, are permitted provided that the following conditions are
2687     met:
2688     * Redistributions of source code must retain the above copyright
2689     notice, this list of conditions and the following disclaimer.
2690     * Redistributions in binary form must reproduce the above
2691     copyright notice, this list of conditions and the following disclaimer
2692     in the documentation and/or other materials provided with the
2693     distribution.
2694     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
2695     "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
2696     LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
2697     A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
2698     OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
2699     SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
2700     LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
2701     DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
2702     THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
2703     (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
2704     OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
2705 
2706     You can contact the author at :
2707     - zstd homepage : http://www.zstd.net/
2708 */
2709 
2710 
2711 /*-****************************************
2712 *  Version
2713 ******************************************/
2714 
2715 /*-****************************************
2716 *  ZSTD Error Management
2717 ******************************************/
2718 /*! ZSTDv06_isError() :
2719 *   tells if a return value is an error code */
2720 unsigned ZSTDv06_isError(size_t code) { return ERR_isError(code); }
2721 
2722 /*! ZSTDv06_getErrorName() :
2723 *   provides error code string from function result (useful for debugging) */
2724 const char* ZSTDv06_getErrorName(size_t code) { return ERR_getErrorName(code); }
2725 
2726 
2727 /* **************************************************************
2728 *  ZBUFF Error Management
2729 ****************************************************************/
2730 unsigned ZBUFFv06_isError(size_t errorCode) { return ERR_isError(errorCode); }
2731 
2732 const char* ZBUFFv06_getErrorName(size_t errorCode) { return ERR_getErrorName(errorCode); }
2733 /*
2734     zstd - standard compression library
2735     Copyright (C) 2014-2016, Yann Collet.
2736 
2737     BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
2738 
2739     Redistribution and use in source and binary forms, with or without
2740     modification, are permitted provided that the following conditions are
2741     met:
2742     * Redistributions of source code must retain the above copyright
2743     notice, this list of conditions and the following disclaimer.
2744     * Redistributions in binary form must reproduce the above
2745     copyright notice, this list of conditions and the following disclaimer
2746     in the documentation and/or other materials provided with the
2747     distribution.
2748     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
2749     "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
2750     LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
2751     A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
2752     OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
2753     SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
2754     LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
2755     DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
2756     THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
2757     (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
2758     OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
2759 
2760     You can contact the author at :
2761     - zstd homepage : http://www.zstd.net
2762 */
2763 
2764 /* ***************************************************************
2765 *  Tuning parameters
2766 *****************************************************************/
2767 /*!
2768  * HEAPMODE :
2769  * Select how default decompression function ZSTDv06_decompress() will allocate memory,
2770  * in memory stack (0), or in memory heap (1, requires malloc())
2771  */
2772 #ifndef ZSTDv06_HEAPMODE
2773 #  define ZSTDv06_HEAPMODE 1
2774 #endif
2775 
2776 
2777 
2778 /*-*******************************************************
2779 *  Compiler specifics
2780 *********************************************************/
2781 #ifdef _MSC_VER    /* Visual Studio */
2782 #  include <intrin.h>                    /* For Visual 2005 */
2783 #  pragma warning(disable : 4127)        /* disable: C4127: conditional expression is constant */
2784 #  pragma warning(disable : 4324)        /* disable: C4324: padded structure */
2785 #endif
2786 
2787 
2788 /*-*************************************
2789 *  Macros
2790 ***************************************/
2791 #define ZSTDv06_isError ERR_isError   /* for inlining */
2792 #define FSEv06_isError  ERR_isError
2793 #define HUFv06_isError  ERR_isError
2794 
2795 
2796 /*_*******************************************************
2797 *  Memory operations
2798 **********************************************************/
2799 static void ZSTDv06_copy4(void* dst, const void* src) { memcpy(dst, src, 4); }
2800 
2801 
2802 /*-*************************************************************
2803 *   Context management
2804 ***************************************************************/
2805 typedef enum { ZSTDds_getFrameHeaderSize, ZSTDds_decodeFrameHeader,
2806                ZSTDds_decodeBlockHeader, ZSTDds_decompressBlock } ZSTDv06_dStage;
2807 
2808 struct ZSTDv06_DCtx_s
2809 {
2810     FSEv06_DTable LLTable[FSEv06_DTABLE_SIZE_U32(LLFSELog)];
2811     FSEv06_DTable OffTable[FSEv06_DTABLE_SIZE_U32(OffFSELog)];
2812     FSEv06_DTable MLTable[FSEv06_DTABLE_SIZE_U32(MLFSELog)];
2813     unsigned   hufTableX4[HUFv06_DTABLE_SIZE(HufLog)];
2814     const void* previousDstEnd;
2815     const void* base;
2816     const void* vBase;
2817     const void* dictEnd;
2818     size_t expected;
2819     size_t headerSize;
2820     ZSTDv06_frameParams fParams;
2821     blockType_t bType;   /* used in ZSTDv06_decompressContinue(), to transfer blockType between header decoding and block decoding stages */
2822     ZSTDv06_dStage stage;
2823     U32 flagRepeatTable;
2824     const BYTE* litPtr;
2825     size_t litSize;
2826     BYTE litBuffer[ZSTDv06_BLOCKSIZE_MAX + WILDCOPY_OVERLENGTH];
2827     BYTE headerBuffer[ZSTDv06_FRAMEHEADERSIZE_MAX];
2828 };  /* typedef'd to ZSTDv06_DCtx within "zstd_static.h" */
2829 
2830 size_t ZSTDv06_sizeofDCtx (void); /* Hidden declaration */
2831 size_t ZSTDv06_sizeofDCtx (void) { return sizeof(ZSTDv06_DCtx); }
2832 
2833 size_t ZSTDv06_decompressBegin(ZSTDv06_DCtx* dctx)
2834 {
2835     dctx->expected = ZSTDv06_frameHeaderSize_min;
2836     dctx->stage = ZSTDds_getFrameHeaderSize;
2837     dctx->previousDstEnd = NULL;
2838     dctx->base = NULL;
2839     dctx->vBase = NULL;
2840     dctx->dictEnd = NULL;
2841     dctx->hufTableX4[0] = HufLog;
2842     dctx->flagRepeatTable = 0;
2843     return 0;
2844 }
2845 
2846 ZSTDv06_DCtx* ZSTDv06_createDCtx(void)
2847 {
2848     ZSTDv06_DCtx* dctx = (ZSTDv06_DCtx*)malloc(sizeof(ZSTDv06_DCtx));
2849     if (dctx==NULL) return NULL;
2850     ZSTDv06_decompressBegin(dctx);
2851     return dctx;
2852 }
2853 
2854 size_t ZSTDv06_freeDCtx(ZSTDv06_DCtx* dctx)
2855 {
2856     free(dctx);
2857     return 0;   /* reserved as a potential error code in the future */
2858 }
2859 
2860 void ZSTDv06_copyDCtx(ZSTDv06_DCtx* dstDCtx, const ZSTDv06_DCtx* srcDCtx)
2861 {
2862     memcpy(dstDCtx, srcDCtx,
2863            sizeof(ZSTDv06_DCtx) - (ZSTDv06_BLOCKSIZE_MAX+WILDCOPY_OVERLENGTH + ZSTDv06_frameHeaderSize_max));  /* no need to copy workspace */
2864 }
2865 
2866 
2867 /*-*************************************************************
2868 *   Decompression section
2869 ***************************************************************/
2870 
2871 /* Frame format description
2872    Frame Header -  [ Block Header - Block ] - Frame End
2873    1) Frame Header
2874       - 4 bytes - Magic Number : ZSTDv06_MAGICNUMBER (defined within zstd_static.h)
2875       - 1 byte  - Frame Descriptor
2876    2) Block Header
2877       - 3 bytes, starting with a 2-bits descriptor
2878                  Uncompressed, Compressed, Frame End, unused
2879    3) Block
2880       See Block Format Description
2881    4) Frame End
2882       - 3 bytes, compatible with Block Header
2883 */
2884 
2885 
2886 /* Frame descriptor
2887 
2888    1 byte, using :
2889    bit 0-3 : windowLog - ZSTDv06_WINDOWLOG_ABSOLUTEMIN   (see zstd_internal.h)
2890    bit 4   : minmatch 4(0) or 3(1)
2891    bit 5   : reserved (must be zero)
2892    bit 6-7 : Frame content size : unknown, 1 byte, 2 bytes, 8 bytes
2893 
2894    Optional : content size (0, 1, 2 or 8 bytes)
2895    0 : unknown
2896    1 : 0-255 bytes
2897    2 : 256 - 65535+256
2898    8 : up to 16 exa
2899 */
2900 
2901 
2902 /* Compressed Block, format description
2903 
2904    Block = Literal Section - Sequences Section
2905    Prerequisite : size of (compressed) block, maximum size of regenerated data
2906 
2907    1) Literal Section
2908 
2909    1.1) Header : 1-5 bytes
2910         flags: 2 bits
2911             00 compressed by Huff0
2912             01 unused
2913             10 is Raw (uncompressed)
2914             11 is Rle
2915             Note : using 01 => Huff0 with precomputed table ?
2916             Note : delta map ? => compressed ?
2917 
2918    1.1.1) Huff0-compressed literal block : 3-5 bytes
2919             srcSize < 1 KB => 3 bytes (2-2-10-10) => single stream
2920             srcSize < 1 KB => 3 bytes (2-2-10-10)
2921             srcSize < 16KB => 4 bytes (2-2-14-14)
2922             else           => 5 bytes (2-2-18-18)
2923             big endian convention
2924 
2925    1.1.2) Raw (uncompressed) literal block header : 1-3 bytes
2926         size :  5 bits: (IS_RAW<<6) + (0<<4) + size
2927                12 bits: (IS_RAW<<6) + (2<<4) + (size>>8)
2928                         size&255
2929                20 bits: (IS_RAW<<6) + (3<<4) + (size>>16)
2930                         size>>8&255
2931                         size&255
2932 
2933    1.1.3) Rle (repeated single byte) literal block header : 1-3 bytes
2934         size :  5 bits: (IS_RLE<<6) + (0<<4) + size
2935                12 bits: (IS_RLE<<6) + (2<<4) + (size>>8)
2936                         size&255
2937                20 bits: (IS_RLE<<6) + (3<<4) + (size>>16)
2938                         size>>8&255
2939                         size&255
2940 
2941    1.1.4) Huff0-compressed literal block, using precomputed CTables : 3-5 bytes
2942             srcSize < 1 KB => 3 bytes (2-2-10-10) => single stream
2943             srcSize < 1 KB => 3 bytes (2-2-10-10)
2944             srcSize < 16KB => 4 bytes (2-2-14-14)
2945             else           => 5 bytes (2-2-18-18)
2946             big endian convention
2947 
2948         1- CTable available (stored into workspace ?)
2949         2- Small input (fast heuristic ? Full comparison ? depend on clevel ?)
2950 
2951 
2952    1.2) Literal block content
2953 
2954    1.2.1) Huff0 block, using sizes from header
2955         See Huff0 format
2956 
2957    1.2.2) Huff0 block, using prepared table
2958 
2959    1.2.3) Raw content
2960 
2961    1.2.4) single byte
2962 
2963 
2964    2) Sequences section
2965       TO DO
2966 */
2967 
2968 /** ZSTDv06_frameHeaderSize() :
2969 *   srcSize must be >= ZSTDv06_frameHeaderSize_min.
2970 *   @return : size of the Frame Header */
2971 static size_t ZSTDv06_frameHeaderSize(const void* src, size_t srcSize)
2972 {
2973     if (srcSize < ZSTDv06_frameHeaderSize_min) return ERROR(srcSize_wrong);
2974     { U32 const fcsId = (((const BYTE*)src)[4]) >> 6;
2975       return ZSTDv06_frameHeaderSize_min + ZSTDv06_fcs_fieldSize[fcsId]; }
2976 }
2977 
2978 
2979 /** ZSTDv06_getFrameParams() :
2980 *   decode Frame Header, or provide expected `srcSize`.
2981 *   @return : 0, `fparamsPtr` is correctly filled,
2982 *            >0, `srcSize` is too small, result is expected `srcSize`,
2983 *             or an error code, which can be tested using ZSTDv06_isError() */
2984 size_t ZSTDv06_getFrameParams(ZSTDv06_frameParams* fparamsPtr, const void* src, size_t srcSize)
2985 {
2986     const BYTE* ip = (const BYTE*)src;
2987 
2988     if (srcSize < ZSTDv06_frameHeaderSize_min) return ZSTDv06_frameHeaderSize_min;
2989     if (MEM_readLE32(src) != ZSTDv06_MAGICNUMBER) return ERROR(prefix_unknown);
2990 
2991     /* ensure there is enough `srcSize` to fully read/decode frame header */
2992     { size_t const fhsize = ZSTDv06_frameHeaderSize(src, srcSize);
2993       if (srcSize < fhsize) return fhsize; }
2994 
2995     memset(fparamsPtr, 0, sizeof(*fparamsPtr));
2996     {   BYTE const frameDesc = ip[4];
2997         fparamsPtr->windowLog = (frameDesc & 0xF) + ZSTDv06_WINDOWLOG_ABSOLUTEMIN;
2998         if ((frameDesc & 0x20) != 0) return ERROR(frameParameter_unsupported);   /* reserved 1 bit */
2999         switch(frameDesc >> 6)  /* fcsId */
3000         {
3001             default:   /* impossible */
3002             case 0 : fparamsPtr->frameContentSize = 0; break;
3003             case 1 : fparamsPtr->frameContentSize = ip[5]; break;
3004             case 2 : fparamsPtr->frameContentSize = MEM_readLE16(ip+5)+256; break;
3005             case 3 : fparamsPtr->frameContentSize = MEM_readLE64(ip+5); break;
3006     }   }
3007     return 0;
3008 }
3009 
3010 
3011 /** ZSTDv06_decodeFrameHeader() :
3012 *   `srcSize` must be the size provided by ZSTDv06_frameHeaderSize().
3013 *   @return : 0 if success, or an error code, which can be tested using ZSTDv06_isError() */
3014 static size_t ZSTDv06_decodeFrameHeader(ZSTDv06_DCtx* zc, const void* src, size_t srcSize)
3015 {
3016     size_t const result = ZSTDv06_getFrameParams(&(zc->fParams), src, srcSize);
3017     if ((MEM_32bits()) && (zc->fParams.windowLog > 25)) return ERROR(frameParameter_unsupported);
3018     return result;
3019 }
3020 
3021 
3022 typedef struct
3023 {
3024     blockType_t blockType;
3025     U32 origSize;
3026 } blockProperties_t;
3027 
3028 /*! ZSTDv06_getcBlockSize() :
3029 *   Provides the size of compressed block from block header `src` */
3030 static size_t ZSTDv06_getcBlockSize(const void* src, size_t srcSize, blockProperties_t* bpPtr)
3031 {
3032     const BYTE* const in = (const BYTE* const)src;
3033     U32 cSize;
3034 
3035     if (srcSize < ZSTDv06_blockHeaderSize) return ERROR(srcSize_wrong);
3036 
3037     bpPtr->blockType = (blockType_t)((*in) >> 6);
3038     cSize = in[2] + (in[1]<<8) + ((in[0] & 7)<<16);
3039     bpPtr->origSize = (bpPtr->blockType == bt_rle) ? cSize : 0;
3040 
3041     if (bpPtr->blockType == bt_end) return 0;
3042     if (bpPtr->blockType == bt_rle) return 1;
3043     return cSize;
3044 }
3045 
3046 
3047 static size_t ZSTDv06_copyRawBlock(void* dst, size_t dstCapacity, const void* src, size_t srcSize)
3048 {
3049     if (dst==NULL) return ERROR(dstSize_tooSmall);
3050     if (srcSize > dstCapacity) return ERROR(dstSize_tooSmall);
3051     memcpy(dst, src, srcSize);
3052     return srcSize;
3053 }
3054 
3055 
3056 /*! ZSTDv06_decodeLiteralsBlock() :
3057     @return : nb of bytes read from src (< srcSize ) */
3058 static size_t ZSTDv06_decodeLiteralsBlock(ZSTDv06_DCtx* dctx,
3059                           const void* src, size_t srcSize)   /* note : srcSize < BLOCKSIZE */
3060 {
3061     const BYTE* const istart = (const BYTE*) src;
3062 
3063     /* any compressed block with literals segment must be at least this size */
3064     if (srcSize < MIN_CBLOCK_SIZE) return ERROR(corruption_detected);
3065 
3066     switch(istart[0]>> 6)
3067     {
3068     case IS_HUF:
3069         {   size_t litSize, litCSize, singleStream=0;
3070             U32 lhSize = ((istart[0]) >> 4) & 3;
3071             if (srcSize < 5) return ERROR(corruption_detected);   /* srcSize >= MIN_CBLOCK_SIZE == 3; here we need up to 5 for lhSize, + cSize (+nbSeq) */
3072             switch(lhSize)
3073             {
3074             case 0: case 1: default:   /* note : default is impossible, since lhSize into [0..3] */
3075                 /* 2 - 2 - 10 - 10 */
3076                 lhSize=3;
3077                 singleStream = istart[0] & 16;
3078                 litSize  = ((istart[0] & 15) << 6) + (istart[1] >> 2);
3079                 litCSize = ((istart[1] &  3) << 8) + istart[2];
3080                 break;
3081             case 2:
3082                 /* 2 - 2 - 14 - 14 */
3083                 lhSize=4;
3084                 litSize  = ((istart[0] & 15) << 10) + (istart[1] << 2) + (istart[2] >> 6);
3085                 litCSize = ((istart[2] & 63) <<  8) + istart[3];
3086                 break;
3087             case 3:
3088                 /* 2 - 2 - 18 - 18 */
3089                 lhSize=5;
3090                 litSize  = ((istart[0] & 15) << 14) + (istart[1] << 6) + (istart[2] >> 2);
3091                 litCSize = ((istart[2] &  3) << 16) + (istart[3] << 8) + istart[4];
3092                 break;
3093             }
3094             if (litSize > ZSTDv06_BLOCKSIZE_MAX) return ERROR(corruption_detected);
3095             if (litCSize + lhSize > srcSize) return ERROR(corruption_detected);
3096 
3097             if (HUFv06_isError(singleStream ?
3098                             HUFv06_decompress1X2(dctx->litBuffer, litSize, istart+lhSize, litCSize) :
3099                             HUFv06_decompress   (dctx->litBuffer, litSize, istart+lhSize, litCSize) ))
3100                 return ERROR(corruption_detected);
3101 
3102             dctx->litPtr = dctx->litBuffer;
3103             dctx->litSize = litSize;
3104             memset(dctx->litBuffer + dctx->litSize, 0, WILDCOPY_OVERLENGTH);
3105             return litCSize + lhSize;
3106         }
3107     case IS_PCH:
3108         {   size_t litSize, litCSize;
3109             U32 lhSize = ((istart[0]) >> 4) & 3;
3110             if (lhSize != 1)  /* only case supported for now : small litSize, single stream */
3111                 return ERROR(corruption_detected);
3112             if (!dctx->flagRepeatTable)
3113                 return ERROR(dictionary_corrupted);
3114 
3115             /* 2 - 2 - 10 - 10 */
3116             lhSize=3;
3117             litSize  = ((istart[0] & 15) << 6) + (istart[1] >> 2);
3118             litCSize = ((istart[1] &  3) << 8) + istart[2];
3119             if (litCSize + lhSize > srcSize) return ERROR(corruption_detected);
3120 
3121             {   size_t const errorCode = HUFv06_decompress1X4_usingDTable(dctx->litBuffer, litSize, istart+lhSize, litCSize, dctx->hufTableX4);
3122                 if (HUFv06_isError(errorCode)) return ERROR(corruption_detected);
3123             }
3124             dctx->litPtr = dctx->litBuffer;
3125             dctx->litSize = litSize;
3126             memset(dctx->litBuffer + dctx->litSize, 0, WILDCOPY_OVERLENGTH);
3127             return litCSize + lhSize;
3128         }
3129     case IS_RAW:
3130         {   size_t litSize;
3131             U32 lhSize = ((istart[0]) >> 4) & 3;
3132             switch(lhSize)
3133             {
3134             case 0: case 1: default:   /* note : default is impossible, since lhSize into [0..3] */
3135                 lhSize=1;
3136                 litSize = istart[0] & 31;
3137                 break;
3138             case 2:
3139                 litSize = ((istart[0] & 15) << 8) + istart[1];
3140                 break;
3141             case 3:
3142                 litSize = ((istart[0] & 15) << 16) + (istart[1] << 8) + istart[2];
3143                 break;
3144             }
3145 
3146             if (lhSize+litSize+WILDCOPY_OVERLENGTH > srcSize) {  /* risk reading beyond src buffer with wildcopy */
3147                 if (litSize+lhSize > srcSize) return ERROR(corruption_detected);
3148                 memcpy(dctx->litBuffer, istart+lhSize, litSize);
3149                 dctx->litPtr = dctx->litBuffer;
3150                 dctx->litSize = litSize;
3151                 memset(dctx->litBuffer + dctx->litSize, 0, WILDCOPY_OVERLENGTH);
3152                 return lhSize+litSize;
3153             }
3154             /* direct reference into compressed stream */
3155             dctx->litPtr = istart+lhSize;
3156             dctx->litSize = litSize;
3157             return lhSize+litSize;
3158         }
3159     case IS_RLE:
3160         {   size_t litSize;
3161             U32 lhSize = ((istart[0]) >> 4) & 3;
3162             switch(lhSize)
3163             {
3164             case 0: case 1: default:   /* note : default is impossible, since lhSize into [0..3] */
3165                 lhSize = 1;
3166                 litSize = istart[0] & 31;
3167                 break;
3168             case 2:
3169                 litSize = ((istart[0] & 15) << 8) + istart[1];
3170                 break;
3171             case 3:
3172                 litSize = ((istart[0] & 15) << 16) + (istart[1] << 8) + istart[2];
3173                 if (srcSize<4) return ERROR(corruption_detected);   /* srcSize >= MIN_CBLOCK_SIZE == 3; here we need lhSize+1 = 4 */
3174                 break;
3175             }
3176             if (litSize > ZSTDv06_BLOCKSIZE_MAX) return ERROR(corruption_detected);
3177             memset(dctx->litBuffer, istart[lhSize], litSize + WILDCOPY_OVERLENGTH);
3178             dctx->litPtr = dctx->litBuffer;
3179             dctx->litSize = litSize;
3180             return lhSize+1;
3181         }
3182     default:
3183         return ERROR(corruption_detected);   /* impossible */
3184     }
3185 }
3186 
3187 
3188 /*! ZSTDv06_buildSeqTable() :
3189     @return : nb bytes read from src,
3190               or an error code if it fails, testable with ZSTDv06_isError()
3191 */
3192 static size_t ZSTDv06_buildSeqTable(FSEv06_DTable* DTable, U32 type, U32 max, U32 maxLog,
3193                                  const void* src, size_t srcSize,
3194                                  const S16* defaultNorm, U32 defaultLog, U32 flagRepeatTable)
3195 {
3196     switch(type)
3197     {
3198     case FSEv06_ENCODING_RLE :
3199         if (!srcSize) return ERROR(srcSize_wrong);
3200         if ( (*(const BYTE*)src) > max) return ERROR(corruption_detected);
3201         FSEv06_buildDTable_rle(DTable, *(const BYTE*)src);   /* if *src > max, data is corrupted */
3202         return 1;
3203     case FSEv06_ENCODING_RAW :
3204         FSEv06_buildDTable(DTable, defaultNorm, max, defaultLog);
3205         return 0;
3206     case FSEv06_ENCODING_STATIC:
3207         if (!flagRepeatTable) return ERROR(corruption_detected);
3208         return 0;
3209     default :   /* impossible */
3210     case FSEv06_ENCODING_DYNAMIC :
3211         {   U32 tableLog;
3212             S16 norm[MaxSeq+1];
3213             size_t const headerSize = FSEv06_readNCount(norm, &max, &tableLog, src, srcSize);
3214             if (FSEv06_isError(headerSize)) return ERROR(corruption_detected);
3215             if (tableLog > maxLog) return ERROR(corruption_detected);
3216             FSEv06_buildDTable(DTable, norm, max, tableLog);
3217             return headerSize;
3218     }   }
3219 }
3220 
3221 
3222 static size_t ZSTDv06_decodeSeqHeaders(int* nbSeqPtr,
3223                              FSEv06_DTable* DTableLL, FSEv06_DTable* DTableML, FSEv06_DTable* DTableOffb, U32 flagRepeatTable,
3224                              const void* src, size_t srcSize)
3225 {
3226     const BYTE* const istart = (const BYTE* const)src;
3227     const BYTE* const iend = istart + srcSize;
3228     const BYTE* ip = istart;
3229 
3230     /* check */
3231     if (srcSize < MIN_SEQUENCES_SIZE) return ERROR(srcSize_wrong);
3232 
3233     /* SeqHead */
3234     {   int nbSeq = *ip++;
3235         if (!nbSeq) { *nbSeqPtr=0; return 1; }
3236         if (nbSeq > 0x7F) {
3237             if (nbSeq == 0xFF) {
3238                 if (ip+2 > iend) return ERROR(srcSize_wrong);
3239                 nbSeq = MEM_readLE16(ip) + LONGNBSEQ, ip+=2;
3240             } else {
3241                 if (ip >= iend) return ERROR(srcSize_wrong);
3242                 nbSeq = ((nbSeq-0x80)<<8) + *ip++;
3243             }
3244         }
3245         *nbSeqPtr = nbSeq;
3246     }
3247 
3248     /* FSE table descriptors */
3249     if (ip + 4 > iend) return ERROR(srcSize_wrong); /* min : header byte + all 3 are "raw", hence no header, but at least xxLog bits per type */
3250     {   U32 const LLtype  = *ip >> 6;
3251         U32 const Offtype = (*ip >> 4) & 3;
3252         U32 const MLtype  = (*ip >> 2) & 3;
3253         ip++;
3254 
3255         /* Build DTables */
3256         {   size_t const bhSize = ZSTDv06_buildSeqTable(DTableLL, LLtype, MaxLL, LLFSELog, ip, iend-ip, LL_defaultNorm, LL_defaultNormLog, flagRepeatTable);
3257             if (ZSTDv06_isError(bhSize)) return ERROR(corruption_detected);
3258             ip += bhSize;
3259         }
3260         {   size_t const bhSize = ZSTDv06_buildSeqTable(DTableOffb, Offtype, MaxOff, OffFSELog, ip, iend-ip, OF_defaultNorm, OF_defaultNormLog, flagRepeatTable);
3261             if (ZSTDv06_isError(bhSize)) return ERROR(corruption_detected);
3262             ip += bhSize;
3263         }
3264         {   size_t const bhSize = ZSTDv06_buildSeqTable(DTableML, MLtype, MaxML, MLFSELog, ip, iend-ip, ML_defaultNorm, ML_defaultNormLog, flagRepeatTable);
3265             if (ZSTDv06_isError(bhSize)) return ERROR(corruption_detected);
3266             ip += bhSize;
3267     }   }
3268 
3269     return ip-istart;
3270 }
3271 
3272 
3273 typedef struct {
3274     size_t litLength;
3275     size_t matchLength;
3276     size_t offset;
3277 } seq_t;
3278 
3279 typedef struct {
3280     BITv06_DStream_t DStream;
3281     FSEv06_DState_t stateLL;
3282     FSEv06_DState_t stateOffb;
3283     FSEv06_DState_t stateML;
3284     size_t prevOffset[ZSTDv06_REP_INIT];
3285 } seqState_t;
3286 
3287 
3288 
3289 static void ZSTDv06_decodeSequence(seq_t* seq, seqState_t* seqState)
3290 {
3291     /* Literal length */
3292     U32 const llCode = FSEv06_peekSymbol(&(seqState->stateLL));
3293     U32 const mlCode = FSEv06_peekSymbol(&(seqState->stateML));
3294     U32 const ofCode = FSEv06_peekSymbol(&(seqState->stateOffb));   /* <= maxOff, by table construction */
3295 
3296     U32 const llBits = LL_bits[llCode];
3297     U32 const mlBits = ML_bits[mlCode];
3298     U32 const ofBits = ofCode;
3299     U32 const totalBits = llBits+mlBits+ofBits;
3300 
3301     static const U32 LL_base[MaxLL+1] = {
3302                              0,  1,  2,  3,  4,  5,  6,  7,  8,  9,   10,    11,    12,    13,    14,     15,
3303                             16, 18, 20, 22, 24, 28, 32, 40, 48, 64, 0x80, 0x100, 0x200, 0x400, 0x800, 0x1000,
3304                             0x2000, 0x4000, 0x8000, 0x10000 };
3305 
3306     static const U32 ML_base[MaxML+1] = {
3307                              0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10,   11,    12,    13,    14,    15,
3308                             16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26,   27,    28,    29,    30,    31,
3309                             32, 34, 36, 38, 40, 44, 48, 56, 64, 80, 96, 0x80, 0x100, 0x200, 0x400, 0x800,
3310                             0x1000, 0x2000, 0x4000, 0x8000, 0x10000 };
3311 
3312     static const U32 OF_base[MaxOff+1] = {
3313                  0,        1,       3,       7,     0xF,     0x1F,     0x3F,     0x7F,
3314                  0xFF,   0x1FF,   0x3FF,   0x7FF,   0xFFF,   0x1FFF,   0x3FFF,   0x7FFF,
3315                  0xFFFF, 0x1FFFF, 0x3FFFF, 0x7FFFF, 0xFFFFF, 0x1FFFFF, 0x3FFFFF, 0x7FFFFF,
3316                  0xFFFFFF, 0x1FFFFFF, 0x3FFFFFF, /*fake*/ 1, 1 };
3317 
3318     /* sequence */
3319     {   size_t offset;
3320         if (!ofCode)
3321             offset = 0;
3322         else {
3323             offset = OF_base[ofCode] + BITv06_readBits(&(seqState->DStream), ofBits);   /* <=  26 bits */
3324             if (MEM_32bits()) BITv06_reloadDStream(&(seqState->DStream));
3325         }
3326 
3327         if (offset < ZSTDv06_REP_NUM) {
3328             if (llCode == 0 && offset <= 1) offset = 1-offset;
3329 
3330             if (offset != 0) {
3331                 size_t temp = seqState->prevOffset[offset];
3332                 if (offset != 1) {
3333                     seqState->prevOffset[2] = seqState->prevOffset[1];
3334                 }
3335                 seqState->prevOffset[1] = seqState->prevOffset[0];
3336                 seqState->prevOffset[0] = offset = temp;
3337 
3338             } else {
3339                 offset = seqState->prevOffset[0];
3340             }
3341         } else {
3342             offset -= ZSTDv06_REP_MOVE;
3343             seqState->prevOffset[2] = seqState->prevOffset[1];
3344             seqState->prevOffset[1] = seqState->prevOffset[0];
3345             seqState->prevOffset[0] = offset;
3346         }
3347         seq->offset = offset;
3348     }
3349 
3350     seq->matchLength = ML_base[mlCode] + MINMATCH + ((mlCode>31) ? BITv06_readBits(&(seqState->DStream), mlBits) : 0);   /* <=  16 bits */
3351     if (MEM_32bits() && (mlBits+llBits>24)) BITv06_reloadDStream(&(seqState->DStream));
3352 
3353     seq->litLength = LL_base[llCode] + ((llCode>15) ? BITv06_readBits(&(seqState->DStream), llBits) : 0);   /* <=  16 bits */
3354     if (MEM_32bits() ||
3355        (totalBits > 64 - 7 - (LLFSELog+MLFSELog+OffFSELog)) ) BITv06_reloadDStream(&(seqState->DStream));
3356 
3357     /* ANS state update */
3358     FSEv06_updateState(&(seqState->stateLL), &(seqState->DStream));   /* <=  9 bits */
3359     FSEv06_updateState(&(seqState->stateML), &(seqState->DStream));   /* <=  9 bits */
3360     if (MEM_32bits()) BITv06_reloadDStream(&(seqState->DStream));     /* <= 18 bits */
3361     FSEv06_updateState(&(seqState->stateOffb), &(seqState->DStream)); /* <=  8 bits */
3362 }
3363 
3364 
3365 static size_t ZSTDv06_execSequence(BYTE* op,
3366                                 BYTE* const oend, seq_t sequence,
3367                                 const BYTE** litPtr, const BYTE* const litLimit,
3368                                 const BYTE* const base, const BYTE* const vBase, const BYTE* const dictEnd)
3369 {
3370     BYTE* const oLitEnd = op + sequence.litLength;
3371     size_t const sequenceLength = sequence.litLength + sequence.matchLength;
3372     BYTE* const oMatchEnd = op + sequenceLength;   /* risk : address space overflow (32-bits) */
3373     BYTE* const oend_8 = oend-8;
3374     const BYTE* const iLitEnd = *litPtr + sequence.litLength;
3375     const BYTE* match = oLitEnd - sequence.offset;
3376 
3377     /* check */
3378     if (oLitEnd > oend_8) return ERROR(dstSize_tooSmall);   /* last match must start at a minimum distance of 8 from oend */
3379     if (oMatchEnd > oend) return ERROR(dstSize_tooSmall);   /* overwrite beyond dst buffer */
3380     if (iLitEnd > litLimit) return ERROR(corruption_detected);   /* over-read beyond lit buffer */
3381 
3382     /* copy Literals */
3383     ZSTDv06_wildcopy(op, *litPtr, sequence.litLength);   /* note : oLitEnd <= oend-8 : no risk of overwrite beyond oend */
3384     op = oLitEnd;
3385     *litPtr = iLitEnd;   /* update for next sequence */
3386 
3387     /* copy Match */
3388     if (sequence.offset > (size_t)(oLitEnd - base)) {
3389         /* offset beyond prefix */
3390         if (sequence.offset > (size_t)(oLitEnd - vBase)) return ERROR(corruption_detected);
3391         match = dictEnd - (base-match);
3392         if (match + sequence.matchLength <= dictEnd) {
3393             memmove(oLitEnd, match, sequence.matchLength);
3394             return sequenceLength;
3395         }
3396         /* span extDict & currentPrefixSegment */
3397         {   size_t const length1 = dictEnd - match;
3398             memmove(oLitEnd, match, length1);
3399             op = oLitEnd + length1;
3400             sequence.matchLength -= length1;
3401             match = base;
3402             if (op > oend_8 || sequence.matchLength < MINMATCH) {
3403               while (op < oMatchEnd) *op++ = *match++;
3404               return sequenceLength;
3405             }
3406     }   }
3407     /* Requirement: op <= oend_8 */
3408 
3409     /* match within prefix */
3410     if (sequence.offset < 8) {
3411         /* close range match, overlap */
3412         static const U32 dec32table[] = { 0, 1, 2, 1, 4, 4, 4, 4 };   /* added */
3413         static const int dec64table[] = { 8, 8, 8, 7, 8, 9,10,11 };   /* subtracted */
3414         int const sub2 = dec64table[sequence.offset];
3415         op[0] = match[0];
3416         op[1] = match[1];
3417         op[2] = match[2];
3418         op[3] = match[3];
3419         match += dec32table[sequence.offset];
3420         ZSTDv06_copy4(op+4, match);
3421         match -= sub2;
3422     } else {
3423         ZSTDv06_copy8(op, match);
3424     }
3425     op += 8; match += 8;
3426 
3427     if (oMatchEnd > oend-(16-MINMATCH)) {
3428         if (op < oend_8) {
3429             ZSTDv06_wildcopy(op, match, oend_8 - op);
3430             match += oend_8 - op;
3431             op = oend_8;
3432         }
3433         while (op < oMatchEnd) *op++ = *match++;
3434     } else {
3435         ZSTDv06_wildcopy(op, match, (ptrdiff_t)sequence.matchLength-8);   /* works even if matchLength < 8 */
3436     }
3437     return sequenceLength;
3438 }
3439 
3440 
3441 static size_t ZSTDv06_decompressSequences(
3442                                ZSTDv06_DCtx* dctx,
3443                                void* dst, size_t maxDstSize,
3444                          const void* seqStart, size_t seqSize)
3445 {
3446     const BYTE* ip = (const BYTE*)seqStart;
3447     const BYTE* const iend = ip + seqSize;
3448     BYTE* const ostart = (BYTE* const)dst;
3449     BYTE* const oend = ostart + maxDstSize;
3450     BYTE* op = ostart;
3451     const BYTE* litPtr = dctx->litPtr;
3452     const BYTE* const litEnd = litPtr + dctx->litSize;
3453     FSEv06_DTable* DTableLL = dctx->LLTable;
3454     FSEv06_DTable* DTableML = dctx->MLTable;
3455     FSEv06_DTable* DTableOffb = dctx->OffTable;
3456     const BYTE* const base = (const BYTE*) (dctx->base);
3457     const BYTE* const vBase = (const BYTE*) (dctx->vBase);
3458     const BYTE* const dictEnd = (const BYTE*) (dctx->dictEnd);
3459     int nbSeq;
3460 
3461     /* Build Decoding Tables */
3462     {   size_t const seqHSize = ZSTDv06_decodeSeqHeaders(&nbSeq, DTableLL, DTableML, DTableOffb, dctx->flagRepeatTable, ip, seqSize);
3463         if (ZSTDv06_isError(seqHSize)) return seqHSize;
3464         ip += seqHSize;
3465         dctx->flagRepeatTable = 0;
3466     }
3467 
3468     /* Regen sequences */
3469     if (nbSeq) {
3470         seq_t sequence;
3471         seqState_t seqState;
3472 
3473         memset(&sequence, 0, sizeof(sequence));
3474         sequence.offset = REPCODE_STARTVALUE;
3475         { U32 i; for (i=0; i<ZSTDv06_REP_INIT; i++) seqState.prevOffset[i] = REPCODE_STARTVALUE; }
3476         { size_t const errorCode = BITv06_initDStream(&(seqState.DStream), ip, iend-ip);
3477           if (ERR_isError(errorCode)) return ERROR(corruption_detected); }
3478         FSEv06_initDState(&(seqState.stateLL), &(seqState.DStream), DTableLL);
3479         FSEv06_initDState(&(seqState.stateOffb), &(seqState.DStream), DTableOffb);
3480         FSEv06_initDState(&(seqState.stateML), &(seqState.DStream), DTableML);
3481 
3482         for ( ; (BITv06_reloadDStream(&(seqState.DStream)) <= BITv06_DStream_completed) && nbSeq ; ) {
3483             nbSeq--;
3484             ZSTDv06_decodeSequence(&sequence, &seqState);
3485 
3486 #if 0  /* debug */
3487             static BYTE* start = NULL;
3488             if (start==NULL) start = op;
3489             size_t pos = (size_t)(op-start);
3490             if ((pos >= 5810037) && (pos < 5810400))
3491                 printf("Dpos %6u :%5u literals & match %3u bytes at distance %6u \n",
3492                        pos, (U32)sequence.litLength, (U32)sequence.matchLength, (U32)sequence.offset);
3493 #endif
3494 
3495             {   size_t const oneSeqSize = ZSTDv06_execSequence(op, oend, sequence, &litPtr, litEnd, base, vBase, dictEnd);
3496                 if (ZSTDv06_isError(oneSeqSize)) return oneSeqSize;
3497                 op += oneSeqSize;
3498         }   }
3499 
3500         /* check if reached exact end */
3501         if (nbSeq) return ERROR(corruption_detected);
3502     }
3503 
3504     /* last literal segment */
3505     {   size_t const lastLLSize = litEnd - litPtr;
3506         if (litPtr > litEnd) return ERROR(corruption_detected);   /* too many literals already used */
3507         if (op+lastLLSize > oend) return ERROR(dstSize_tooSmall);
3508         if (lastLLSize > 0) {
3509             memcpy(op, litPtr, lastLLSize);
3510             op += lastLLSize;
3511         }
3512     }
3513 
3514     return op-ostart;
3515 }
3516 
3517 
3518 static void ZSTDv06_checkContinuity(ZSTDv06_DCtx* dctx, const void* dst)
3519 {
3520     if (dst != dctx->previousDstEnd) {   /* not contiguous */
3521         dctx->dictEnd = dctx->previousDstEnd;
3522         dctx->vBase = (const char*)dst - ((const char*)(dctx->previousDstEnd) - (const char*)(dctx->base));
3523         dctx->base = dst;
3524         dctx->previousDstEnd = dst;
3525     }
3526 }
3527 
3528 
3529 static size_t ZSTDv06_decompressBlock_internal(ZSTDv06_DCtx* dctx,
3530                             void* dst, size_t dstCapacity,
3531                       const void* src, size_t srcSize)
3532 {   /* blockType == blockCompressed */
3533     const BYTE* ip = (const BYTE*)src;
3534 
3535     if (srcSize >= ZSTDv06_BLOCKSIZE_MAX) return ERROR(srcSize_wrong);
3536 
3537     /* Decode literals sub-block */
3538     {   size_t const litCSize = ZSTDv06_decodeLiteralsBlock(dctx, src, srcSize);
3539         if (ZSTDv06_isError(litCSize)) return litCSize;
3540         ip += litCSize;
3541         srcSize -= litCSize;
3542     }
3543     return ZSTDv06_decompressSequences(dctx, dst, dstCapacity, ip, srcSize);
3544 }
3545 
3546 
3547 size_t ZSTDv06_decompressBlock(ZSTDv06_DCtx* dctx,
3548                             void* dst, size_t dstCapacity,
3549                       const void* src, size_t srcSize)
3550 {
3551     ZSTDv06_checkContinuity(dctx, dst);
3552     return ZSTDv06_decompressBlock_internal(dctx, dst, dstCapacity, src, srcSize);
3553 }
3554 
3555 
3556 /*! ZSTDv06_decompressFrame() :
3557 *   `dctx` must be properly initialized */
3558 static size_t ZSTDv06_decompressFrame(ZSTDv06_DCtx* dctx,
3559                                  void* dst, size_t dstCapacity,
3560                                  const void* src, size_t srcSize)
3561 {
3562     const BYTE* ip = (const BYTE*)src;
3563     const BYTE* const iend = ip + srcSize;
3564     BYTE* const ostart = (BYTE* const)dst;
3565     BYTE* op = ostart;
3566     BYTE* const oend = ostart + dstCapacity;
3567     size_t remainingSize = srcSize;
3568     blockProperties_t blockProperties = { bt_compressed, 0 };
3569 
3570     /* check */
3571     if (srcSize < ZSTDv06_frameHeaderSize_min+ZSTDv06_blockHeaderSize) return ERROR(srcSize_wrong);
3572 
3573     /* Frame Header */
3574     {   size_t const frameHeaderSize = ZSTDv06_frameHeaderSize(src, ZSTDv06_frameHeaderSize_min);
3575         if (ZSTDv06_isError(frameHeaderSize)) return frameHeaderSize;
3576         if (srcSize < frameHeaderSize+ZSTDv06_blockHeaderSize) return ERROR(srcSize_wrong);
3577         if (ZSTDv06_decodeFrameHeader(dctx, src, frameHeaderSize)) return ERROR(corruption_detected);
3578         ip += frameHeaderSize; remainingSize -= frameHeaderSize;
3579     }
3580 
3581     /* Loop on each block */
3582     while (1) {
3583         size_t decodedSize=0;
3584         size_t const cBlockSize = ZSTDv06_getcBlockSize(ip, iend-ip, &blockProperties);
3585         if (ZSTDv06_isError(cBlockSize)) return cBlockSize;
3586 
3587         ip += ZSTDv06_blockHeaderSize;
3588         remainingSize -= ZSTDv06_blockHeaderSize;
3589         if (cBlockSize > remainingSize) return ERROR(srcSize_wrong);
3590 
3591         switch(blockProperties.blockType)
3592         {
3593         case bt_compressed:
3594             decodedSize = ZSTDv06_decompressBlock_internal(dctx, op, oend-op, ip, cBlockSize);
3595             break;
3596         case bt_raw :
3597             decodedSize = ZSTDv06_copyRawBlock(op, oend-op, ip, cBlockSize);
3598             break;
3599         case bt_rle :
3600             return ERROR(GENERIC);   /* not yet supported */
3601             break;
3602         case bt_end :
3603             /* end of frame */
3604             if (remainingSize) return ERROR(srcSize_wrong);
3605             break;
3606         default:
3607             return ERROR(GENERIC);   /* impossible */
3608         }
3609         if (cBlockSize == 0) break;   /* bt_end */
3610 
3611         if (ZSTDv06_isError(decodedSize)) return decodedSize;
3612         op += decodedSize;
3613         ip += cBlockSize;
3614         remainingSize -= cBlockSize;
3615     }
3616 
3617     return op-ostart;
3618 }
3619 
3620 
3621 size_t ZSTDv06_decompress_usingPreparedDCtx(ZSTDv06_DCtx* dctx, const ZSTDv06_DCtx* refDCtx,
3622                                          void* dst, size_t dstCapacity,
3623                                    const void* src, size_t srcSize)
3624 {
3625     ZSTDv06_copyDCtx(dctx, refDCtx);
3626     ZSTDv06_checkContinuity(dctx, dst);
3627     return ZSTDv06_decompressFrame(dctx, dst, dstCapacity, src, srcSize);
3628 }
3629 
3630 
3631 size_t ZSTDv06_decompress_usingDict(ZSTDv06_DCtx* dctx,
3632                                  void* dst, size_t dstCapacity,
3633                                  const void* src, size_t srcSize,
3634                                  const void* dict, size_t dictSize)
3635 {
3636     ZSTDv06_decompressBegin_usingDict(dctx, dict, dictSize);
3637     ZSTDv06_checkContinuity(dctx, dst);
3638     return ZSTDv06_decompressFrame(dctx, dst, dstCapacity, src, srcSize);
3639 }
3640 
3641 
3642 size_t ZSTDv06_decompressDCtx(ZSTDv06_DCtx* dctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize)
3643 {
3644     return ZSTDv06_decompress_usingDict(dctx, dst, dstCapacity, src, srcSize, NULL, 0);
3645 }
3646 
3647 
3648 size_t ZSTDv06_decompress(void* dst, size_t dstCapacity, const void* src, size_t srcSize)
3649 {
3650 #if defined(ZSTDv06_HEAPMODE) && (ZSTDv06_HEAPMODE==1)
3651     size_t regenSize;
3652     ZSTDv06_DCtx* dctx = ZSTDv06_createDCtx();
3653     if (dctx==NULL) return ERROR(memory_allocation);
3654     regenSize = ZSTDv06_decompressDCtx(dctx, dst, dstCapacity, src, srcSize);
3655     ZSTDv06_freeDCtx(dctx);
3656     return regenSize;
3657 #else   /* stack mode */
3658     ZSTDv06_DCtx dctx;
3659     return ZSTDv06_decompressDCtx(&dctx, dst, dstCapacity, src, srcSize);
3660 #endif
3661 }
3662 
3663 /* ZSTD_errorFrameSizeInfoLegacy() :
3664    assumes `cSize` and `dBound` are _not_ NULL */
3665 static void ZSTD_errorFrameSizeInfoLegacy(size_t* cSize, unsigned long long* dBound, size_t ret)
3666 {
3667     *cSize = ret;
3668     *dBound = ZSTD_CONTENTSIZE_ERROR;
3669 }
3670 
3671 void ZSTDv06_findFrameSizeInfoLegacy(const void *src, size_t srcSize, size_t* cSize, unsigned long long* dBound)
3672 {
3673     const BYTE* ip = (const BYTE*)src;
3674     size_t remainingSize = srcSize;
3675     size_t nbBlocks = 0;
3676     blockProperties_t blockProperties = { bt_compressed, 0 };
3677 
3678     /* Frame Header */
3679     {   size_t const frameHeaderSize = ZSTDv06_frameHeaderSize(src, srcSize);
3680         if (ZSTDv06_isError(frameHeaderSize)) {
3681             ZSTD_errorFrameSizeInfoLegacy(cSize, dBound, frameHeaderSize);
3682             return;
3683         }
3684         if (MEM_readLE32(src) != ZSTDv06_MAGICNUMBER) {
3685             ZSTD_errorFrameSizeInfoLegacy(cSize, dBound, ERROR(prefix_unknown));
3686             return;
3687         }
3688         if (srcSize < frameHeaderSize+ZSTDv06_blockHeaderSize) {
3689             ZSTD_errorFrameSizeInfoLegacy(cSize, dBound, ERROR(srcSize_wrong));
3690             return;
3691         }
3692         ip += frameHeaderSize; remainingSize -= frameHeaderSize;
3693     }
3694 
3695     /* Loop on each block */
3696     while (1) {
3697         size_t const cBlockSize = ZSTDv06_getcBlockSize(ip, remainingSize, &blockProperties);
3698         if (ZSTDv06_isError(cBlockSize)) {
3699             ZSTD_errorFrameSizeInfoLegacy(cSize, dBound, cBlockSize);
3700             return;
3701         }
3702 
3703         ip += ZSTDv06_blockHeaderSize;
3704         remainingSize -= ZSTDv06_blockHeaderSize;
3705         if (cBlockSize > remainingSize) {
3706             ZSTD_errorFrameSizeInfoLegacy(cSize, dBound, ERROR(srcSize_wrong));
3707             return;
3708         }
3709 
3710         if (cBlockSize == 0) break;   /* bt_end */
3711 
3712         ip += cBlockSize;
3713         remainingSize -= cBlockSize;
3714         nbBlocks++;
3715     }
3716 
3717     *cSize = ip - (const BYTE*)src;
3718     *dBound = nbBlocks * ZSTDv06_BLOCKSIZE_MAX;
3719 }
3720 
3721 /*_******************************
3722 *  Streaming Decompression API
3723 ********************************/
3724 size_t ZSTDv06_nextSrcSizeToDecompress(ZSTDv06_DCtx* dctx)
3725 {
3726     return dctx->expected;
3727 }
3728 
3729 size_t ZSTDv06_decompressContinue(ZSTDv06_DCtx* dctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize)
3730 {
3731     /* Sanity check */
3732     if (srcSize != dctx->expected) return ERROR(srcSize_wrong);
3733     if (dstCapacity) ZSTDv06_checkContinuity(dctx, dst);
3734 
3735     /* Decompress : frame header; part 1 */
3736     switch (dctx->stage)
3737     {
3738     case ZSTDds_getFrameHeaderSize :
3739         if (srcSize != ZSTDv06_frameHeaderSize_min) return ERROR(srcSize_wrong);   /* impossible */
3740         dctx->headerSize = ZSTDv06_frameHeaderSize(src, ZSTDv06_frameHeaderSize_min);
3741         if (ZSTDv06_isError(dctx->headerSize)) return dctx->headerSize;
3742         memcpy(dctx->headerBuffer, src, ZSTDv06_frameHeaderSize_min);
3743         if (dctx->headerSize > ZSTDv06_frameHeaderSize_min) {
3744             dctx->expected = dctx->headerSize - ZSTDv06_frameHeaderSize_min;
3745             dctx->stage = ZSTDds_decodeFrameHeader;
3746             return 0;
3747         }
3748         dctx->expected = 0;   /* not necessary to copy more */
3749 	/* fall-through */
3750     case ZSTDds_decodeFrameHeader:
3751         {   size_t result;
3752             memcpy(dctx->headerBuffer + ZSTDv06_frameHeaderSize_min, src, dctx->expected);
3753             result = ZSTDv06_decodeFrameHeader(dctx, dctx->headerBuffer, dctx->headerSize);
3754             if (ZSTDv06_isError(result)) return result;
3755             dctx->expected = ZSTDv06_blockHeaderSize;
3756             dctx->stage = ZSTDds_decodeBlockHeader;
3757             return 0;
3758         }
3759     case ZSTDds_decodeBlockHeader:
3760         {   blockProperties_t bp;
3761             size_t const cBlockSize = ZSTDv06_getcBlockSize(src, ZSTDv06_blockHeaderSize, &bp);
3762             if (ZSTDv06_isError(cBlockSize)) return cBlockSize;
3763             if (bp.blockType == bt_end) {
3764                 dctx->expected = 0;
3765                 dctx->stage = ZSTDds_getFrameHeaderSize;
3766             } else {
3767                 dctx->expected = cBlockSize;
3768                 dctx->bType = bp.blockType;
3769                 dctx->stage = ZSTDds_decompressBlock;
3770             }
3771             return 0;
3772         }
3773     case ZSTDds_decompressBlock:
3774         {   size_t rSize;
3775             switch(dctx->bType)
3776             {
3777             case bt_compressed:
3778                 rSize = ZSTDv06_decompressBlock_internal(dctx, dst, dstCapacity, src, srcSize);
3779                 break;
3780             case bt_raw :
3781                 rSize = ZSTDv06_copyRawBlock(dst, dstCapacity, src, srcSize);
3782                 break;
3783             case bt_rle :
3784                 return ERROR(GENERIC);   /* not yet handled */
3785                 break;
3786             case bt_end :   /* should never happen (filtered at phase 1) */
3787                 rSize = 0;
3788                 break;
3789             default:
3790                 return ERROR(GENERIC);   /* impossible */
3791             }
3792             dctx->stage = ZSTDds_decodeBlockHeader;
3793             dctx->expected = ZSTDv06_blockHeaderSize;
3794             dctx->previousDstEnd = (char*)dst + rSize;
3795             return rSize;
3796         }
3797     default:
3798         return ERROR(GENERIC);   /* impossible */
3799     }
3800 }
3801 
3802 
3803 static void ZSTDv06_refDictContent(ZSTDv06_DCtx* dctx, const void* dict, size_t dictSize)
3804 {
3805     dctx->dictEnd = dctx->previousDstEnd;
3806     dctx->vBase = (const char*)dict - ((const char*)(dctx->previousDstEnd) - (const char*)(dctx->base));
3807     dctx->base = dict;
3808     dctx->previousDstEnd = (const char*)dict + dictSize;
3809 }
3810 
3811 static size_t ZSTDv06_loadEntropy(ZSTDv06_DCtx* dctx, const void* dict, size_t dictSize)
3812 {
3813     size_t hSize, offcodeHeaderSize, matchlengthHeaderSize, litlengthHeaderSize;
3814 
3815     hSize = HUFv06_readDTableX4(dctx->hufTableX4, dict, dictSize);
3816     if (HUFv06_isError(hSize)) return ERROR(dictionary_corrupted);
3817     dict = (const char*)dict + hSize;
3818     dictSize -= hSize;
3819 
3820     {   short offcodeNCount[MaxOff+1];
3821         U32 offcodeMaxValue=MaxOff, offcodeLog;
3822         offcodeHeaderSize = FSEv06_readNCount(offcodeNCount, &offcodeMaxValue, &offcodeLog, dict, dictSize);
3823         if (FSEv06_isError(offcodeHeaderSize)) return ERROR(dictionary_corrupted);
3824         if (offcodeLog > OffFSELog) return ERROR(dictionary_corrupted);
3825         { size_t const errorCode = FSEv06_buildDTable(dctx->OffTable, offcodeNCount, offcodeMaxValue, offcodeLog);
3826           if (FSEv06_isError(errorCode)) return ERROR(dictionary_corrupted); }
3827         dict = (const char*)dict + offcodeHeaderSize;
3828         dictSize -= offcodeHeaderSize;
3829     }
3830 
3831     {   short matchlengthNCount[MaxML+1];
3832         unsigned matchlengthMaxValue = MaxML, matchlengthLog;
3833         matchlengthHeaderSize = FSEv06_readNCount(matchlengthNCount, &matchlengthMaxValue, &matchlengthLog, dict, dictSize);
3834         if (FSEv06_isError(matchlengthHeaderSize)) return ERROR(dictionary_corrupted);
3835         if (matchlengthLog > MLFSELog) return ERROR(dictionary_corrupted);
3836         { size_t const errorCode = FSEv06_buildDTable(dctx->MLTable, matchlengthNCount, matchlengthMaxValue, matchlengthLog);
3837           if (FSEv06_isError(errorCode)) return ERROR(dictionary_corrupted); }
3838         dict = (const char*)dict + matchlengthHeaderSize;
3839         dictSize -= matchlengthHeaderSize;
3840     }
3841 
3842     {   short litlengthNCount[MaxLL+1];
3843         unsigned litlengthMaxValue = MaxLL, litlengthLog;
3844         litlengthHeaderSize = FSEv06_readNCount(litlengthNCount, &litlengthMaxValue, &litlengthLog, dict, dictSize);
3845         if (FSEv06_isError(litlengthHeaderSize)) return ERROR(dictionary_corrupted);
3846         if (litlengthLog > LLFSELog) return ERROR(dictionary_corrupted);
3847         { size_t const errorCode = FSEv06_buildDTable(dctx->LLTable, litlengthNCount, litlengthMaxValue, litlengthLog);
3848           if (FSEv06_isError(errorCode)) return ERROR(dictionary_corrupted); }
3849     }
3850 
3851     dctx->flagRepeatTable = 1;
3852     return hSize + offcodeHeaderSize + matchlengthHeaderSize + litlengthHeaderSize;
3853 }
3854 
3855 static size_t ZSTDv06_decompress_insertDictionary(ZSTDv06_DCtx* dctx, const void* dict, size_t dictSize)
3856 {
3857     size_t eSize;
3858     U32 const magic = MEM_readLE32(dict);
3859     if (magic != ZSTDv06_DICT_MAGIC) {
3860         /* pure content mode */
3861         ZSTDv06_refDictContent(dctx, dict, dictSize);
3862         return 0;
3863     }
3864     /* load entropy tables */
3865     dict = (const char*)dict + 4;
3866     dictSize -= 4;
3867     eSize = ZSTDv06_loadEntropy(dctx, dict, dictSize);
3868     if (ZSTDv06_isError(eSize)) return ERROR(dictionary_corrupted);
3869 
3870     /* reference dictionary content */
3871     dict = (const char*)dict + eSize;
3872     dictSize -= eSize;
3873     ZSTDv06_refDictContent(dctx, dict, dictSize);
3874 
3875     return 0;
3876 }
3877 
3878 
3879 size_t ZSTDv06_decompressBegin_usingDict(ZSTDv06_DCtx* dctx, const void* dict, size_t dictSize)
3880 {
3881     { size_t const errorCode = ZSTDv06_decompressBegin(dctx);
3882       if (ZSTDv06_isError(errorCode)) return errorCode; }
3883 
3884     if (dict && dictSize) {
3885         size_t const errorCode = ZSTDv06_decompress_insertDictionary(dctx, dict, dictSize);
3886         if (ZSTDv06_isError(errorCode)) return ERROR(dictionary_corrupted);
3887     }
3888 
3889     return 0;
3890 }
3891 
3892 /*
3893     Buffered version of Zstd compression library
3894     Copyright (C) 2015-2016, Yann Collet.
3895 
3896     BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
3897 
3898     Redistribution and use in source and binary forms, with or without
3899     modification, are permitted provided that the following conditions are
3900     met:
3901     * Redistributions of source code must retain the above copyright
3902     notice, this list of conditions and the following disclaimer.
3903     * Redistributions in binary form must reproduce the above
3904     copyright notice, this list of conditions and the following disclaimer
3905     in the documentation and/or other materials provided with the
3906     distribution.
3907     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
3908     "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
3909     LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
3910     A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
3911     OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
3912     SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
3913     LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
3914     DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
3915     THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
3916     (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
3917     OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
3918 
3919     You can contact the author at :
3920     - zstd homepage : http://www.zstd.net/
3921 */
3922 
3923 
3924 /*-***************************************************************************
3925 *  Streaming decompression howto
3926 *
3927 *  A ZBUFFv06_DCtx object is required to track streaming operations.
3928 *  Use ZBUFFv06_createDCtx() and ZBUFFv06_freeDCtx() to create/release resources.
3929 *  Use ZBUFFv06_decompressInit() to start a new decompression operation,
3930 *   or ZBUFFv06_decompressInitDictionary() if decompression requires a dictionary.
3931 *  Note that ZBUFFv06_DCtx objects can be re-init multiple times.
3932 *
3933 *  Use ZBUFFv06_decompressContinue() repetitively to consume your input.
3934 *  *srcSizePtr and *dstCapacityPtr can be any size.
3935 *  The function will report how many bytes were read or written by modifying *srcSizePtr and *dstCapacityPtr.
3936 *  Note that it may not consume the entire input, in which case it's up to the caller to present remaining input again.
3937 *  The content of @dst will be overwritten (up to *dstCapacityPtr) at each function call, so save its content if it matters, or change @dst.
3938 *  @return : a hint to preferred nb of bytes to use as input for next function call (it's only a hint, to help latency),
3939 *            or 0 when a frame is completely decoded,
3940 *            or an error code, which can be tested using ZBUFFv06_isError().
3941 *
3942 *  Hint : recommended buffer sizes (not compulsory) : ZBUFFv06_recommendedDInSize() and ZBUFFv06_recommendedDOutSize()
3943 *  output : ZBUFFv06_recommendedDOutSize==128 KB block size is the internal unit, it ensures it's always possible to write a full block when decoded.
3944 *  input  : ZBUFFv06_recommendedDInSize == 128KB + 3;
3945 *           just follow indications from ZBUFFv06_decompressContinue() to minimize latency. It should always be <= 128 KB + 3 .
3946 * *******************************************************************************/
3947 
3948 typedef enum { ZBUFFds_init, ZBUFFds_loadHeader,
3949                ZBUFFds_read, ZBUFFds_load, ZBUFFds_flush } ZBUFFv06_dStage;
3950 
3951 /* *** Resource management *** */
3952 struct ZBUFFv06_DCtx_s {
3953     ZSTDv06_DCtx* zd;
3954     ZSTDv06_frameParams fParams;
3955     ZBUFFv06_dStage stage;
3956     char*  inBuff;
3957     size_t inBuffSize;
3958     size_t inPos;
3959     char*  outBuff;
3960     size_t outBuffSize;
3961     size_t outStart;
3962     size_t outEnd;
3963     size_t blockSize;
3964     BYTE headerBuffer[ZSTDv06_FRAMEHEADERSIZE_MAX];
3965     size_t lhSize;
3966 };   /* typedef'd to ZBUFFv06_DCtx within "zstd_buffered.h" */
3967 
3968 
3969 ZBUFFv06_DCtx* ZBUFFv06_createDCtx(void)
3970 {
3971     ZBUFFv06_DCtx* zbd = (ZBUFFv06_DCtx*)malloc(sizeof(ZBUFFv06_DCtx));
3972     if (zbd==NULL) return NULL;
3973     memset(zbd, 0, sizeof(*zbd));
3974     zbd->zd = ZSTDv06_createDCtx();
3975     zbd->stage = ZBUFFds_init;
3976     return zbd;
3977 }
3978 
3979 size_t ZBUFFv06_freeDCtx(ZBUFFv06_DCtx* zbd)
3980 {
3981     if (zbd==NULL) return 0;   /* support free on null */
3982     ZSTDv06_freeDCtx(zbd->zd);
3983     free(zbd->inBuff);
3984     free(zbd->outBuff);
3985     free(zbd);
3986     return 0;
3987 }
3988 
3989 
3990 /* *** Initialization *** */
3991 
3992 size_t ZBUFFv06_decompressInitDictionary(ZBUFFv06_DCtx* zbd, const void* dict, size_t dictSize)
3993 {
3994     zbd->stage = ZBUFFds_loadHeader;
3995     zbd->lhSize = zbd->inPos = zbd->outStart = zbd->outEnd = 0;
3996     return ZSTDv06_decompressBegin_usingDict(zbd->zd, dict, dictSize);
3997 }
3998 
3999 size_t ZBUFFv06_decompressInit(ZBUFFv06_DCtx* zbd)
4000 {
4001     return ZBUFFv06_decompressInitDictionary(zbd, NULL, 0);
4002 }
4003 
4004 
4005 
4006 MEM_STATIC size_t ZBUFFv06_limitCopy(void* dst, size_t dstCapacity, const void* src, size_t srcSize)
4007 {
4008     size_t length = MIN(dstCapacity, srcSize);
4009     if (length > 0) {
4010         memcpy(dst, src, length);
4011     }
4012     return length;
4013 }
4014 
4015 
4016 /* *** Decompression *** */
4017 
4018 size_t ZBUFFv06_decompressContinue(ZBUFFv06_DCtx* zbd,
4019                                 void* dst, size_t* dstCapacityPtr,
4020                           const void* src, size_t* srcSizePtr)
4021 {
4022     const char* const istart = (const char*)src;
4023     const char* const iend = istart + *srcSizePtr;
4024     const char* ip = istart;
4025     char* const ostart = (char*)dst;
4026     char* const oend = ostart + *dstCapacityPtr;
4027     char* op = ostart;
4028     U32 notDone = 1;
4029 
4030     while (notDone) {
4031         switch(zbd->stage)
4032         {
4033         case ZBUFFds_init :
4034             return ERROR(init_missing);
4035 
4036         case ZBUFFds_loadHeader :
4037             {   size_t const hSize = ZSTDv06_getFrameParams(&(zbd->fParams), zbd->headerBuffer, zbd->lhSize);
4038                 if (hSize != 0) {
4039                     size_t const toLoad = hSize - zbd->lhSize;   /* if hSize!=0, hSize > zbd->lhSize */
4040                     if (ZSTDv06_isError(hSize)) return hSize;
4041                     if (toLoad > (size_t)(iend-ip)) {   /* not enough input to load full header */
4042                         memcpy(zbd->headerBuffer + zbd->lhSize, ip, iend-ip);
4043                         zbd->lhSize += iend-ip;
4044                         *dstCapacityPtr = 0;
4045                         return (hSize - zbd->lhSize) + ZSTDv06_blockHeaderSize;   /* remaining header bytes + next block header */
4046                     }
4047                     memcpy(zbd->headerBuffer + zbd->lhSize, ip, toLoad); zbd->lhSize = hSize; ip += toLoad;
4048                     break;
4049             }   }
4050 
4051             /* Consume header */
4052             {   size_t const h1Size = ZSTDv06_nextSrcSizeToDecompress(zbd->zd);  /* == ZSTDv06_frameHeaderSize_min */
4053                 size_t const h1Result = ZSTDv06_decompressContinue(zbd->zd, NULL, 0, zbd->headerBuffer, h1Size);
4054                 if (ZSTDv06_isError(h1Result)) return h1Result;
4055                 if (h1Size < zbd->lhSize) {   /* long header */
4056                     size_t const h2Size = ZSTDv06_nextSrcSizeToDecompress(zbd->zd);
4057                     size_t const h2Result = ZSTDv06_decompressContinue(zbd->zd, NULL, 0, zbd->headerBuffer+h1Size, h2Size);
4058                     if (ZSTDv06_isError(h2Result)) return h2Result;
4059             }   }
4060 
4061             /* Frame header instruct buffer sizes */
4062             {   size_t const blockSize = MIN(1 << zbd->fParams.windowLog, ZSTDv06_BLOCKSIZE_MAX);
4063                 zbd->blockSize = blockSize;
4064                 if (zbd->inBuffSize < blockSize) {
4065                     free(zbd->inBuff);
4066                     zbd->inBuffSize = blockSize;
4067                     zbd->inBuff = (char*)malloc(blockSize);
4068                     if (zbd->inBuff == NULL) return ERROR(memory_allocation);
4069                 }
4070                 {   size_t const neededOutSize = ((size_t)1 << zbd->fParams.windowLog) + blockSize + WILDCOPY_OVERLENGTH * 2;
4071                     if (zbd->outBuffSize < neededOutSize) {
4072                         free(zbd->outBuff);
4073                         zbd->outBuffSize = neededOutSize;
4074                         zbd->outBuff = (char*)malloc(neededOutSize);
4075                         if (zbd->outBuff == NULL) return ERROR(memory_allocation);
4076             }   }   }
4077             zbd->stage = ZBUFFds_read;
4078 	    /* fall-through */
4079         case ZBUFFds_read:
4080             {   size_t const neededInSize = ZSTDv06_nextSrcSizeToDecompress(zbd->zd);
4081                 if (neededInSize==0) {  /* end of frame */
4082                     zbd->stage = ZBUFFds_init;
4083                     notDone = 0;
4084                     break;
4085                 }
4086                 if ((size_t)(iend-ip) >= neededInSize) {  /* decode directly from src */
4087                     size_t const decodedSize = ZSTDv06_decompressContinue(zbd->zd,
4088                         zbd->outBuff + zbd->outStart, zbd->outBuffSize - zbd->outStart,
4089                         ip, neededInSize);
4090                     if (ZSTDv06_isError(decodedSize)) return decodedSize;
4091                     ip += neededInSize;
4092                     if (!decodedSize) break;   /* this was just a header */
4093                     zbd->outEnd = zbd->outStart +  decodedSize;
4094                     zbd->stage = ZBUFFds_flush;
4095                     break;
4096                 }
4097                 if (ip==iend) { notDone = 0; break; }   /* no more input */
4098                 zbd->stage = ZBUFFds_load;
4099             }
4100 	    /* fall-through */
4101         case ZBUFFds_load:
4102             {   size_t const neededInSize = ZSTDv06_nextSrcSizeToDecompress(zbd->zd);
4103                 size_t const toLoad = neededInSize - zbd->inPos;   /* should always be <= remaining space within inBuff */
4104                 size_t loadedSize;
4105                 if (toLoad > zbd->inBuffSize - zbd->inPos) return ERROR(corruption_detected);   /* should never happen */
4106                 loadedSize = ZBUFFv06_limitCopy(zbd->inBuff + zbd->inPos, toLoad, ip, iend-ip);
4107                 ip += loadedSize;
4108                 zbd->inPos += loadedSize;
4109                 if (loadedSize < toLoad) { notDone = 0; break; }   /* not enough input, wait for more */
4110 
4111                 /* decode loaded input */
4112                 {   size_t const decodedSize = ZSTDv06_decompressContinue(zbd->zd,
4113                         zbd->outBuff + zbd->outStart, zbd->outBuffSize - zbd->outStart,
4114                         zbd->inBuff, neededInSize);
4115                     if (ZSTDv06_isError(decodedSize)) return decodedSize;
4116                     zbd->inPos = 0;   /* input is consumed */
4117                     if (!decodedSize) { zbd->stage = ZBUFFds_read; break; }   /* this was just a header */
4118                     zbd->outEnd = zbd->outStart +  decodedSize;
4119                     zbd->stage = ZBUFFds_flush;
4120                     /* break; */ /* ZBUFFds_flush follows */
4121                 }
4122 	    }
4123 	    /* fall-through */
4124         case ZBUFFds_flush:
4125             {   size_t const toFlushSize = zbd->outEnd - zbd->outStart;
4126                 size_t const flushedSize = ZBUFFv06_limitCopy(op, oend-op, zbd->outBuff + zbd->outStart, toFlushSize);
4127                 op += flushedSize;
4128                 zbd->outStart += flushedSize;
4129                 if (flushedSize == toFlushSize) {
4130                     zbd->stage = ZBUFFds_read;
4131                     if (zbd->outStart + zbd->blockSize > zbd->outBuffSize)
4132                         zbd->outStart = zbd->outEnd = 0;
4133                     break;
4134                 }
4135                 /* cannot flush everything */
4136                 notDone = 0;
4137                 break;
4138             }
4139         default: return ERROR(GENERIC);   /* impossible */
4140     }   }
4141 
4142     /* result */
4143     *srcSizePtr = ip-istart;
4144     *dstCapacityPtr = op-ostart;
4145     {   size_t nextSrcSizeHint = ZSTDv06_nextSrcSizeToDecompress(zbd->zd);
4146         if (nextSrcSizeHint > ZSTDv06_blockHeaderSize) nextSrcSizeHint+= ZSTDv06_blockHeaderSize;   /* get following block header too */
4147         nextSrcSizeHint -= zbd->inPos;   /* already loaded*/
4148         return nextSrcSizeHint;
4149     }
4150 }
4151 
4152 
4153 
4154 /* *************************************
4155 *  Tool functions
4156 ***************************************/
4157 size_t ZBUFFv06_recommendedDInSize(void)  { return ZSTDv06_BLOCKSIZE_MAX + ZSTDv06_blockHeaderSize /* block header size*/ ; }
4158 size_t ZBUFFv06_recommendedDOutSize(void) { return ZSTDv06_BLOCKSIZE_MAX; }
4159