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 /******************************************
13 * Includes
14 ******************************************/
15 #include <stddef.h> /* size_t, ptrdiff_t */
16 #include "zstd_v01.h"
17 #include "../common/error_private.h"
18
19
20 /******************************************
21 * Static allocation
22 ******************************************/
23 /* You can statically allocate FSE CTable/DTable as a table of unsigned using below macro */
24 #define FSE_DTABLE_SIZE_U32(maxTableLog) (1 + (1<<maxTableLog))
25
26 /* You can statically allocate Huff0 DTable as a table of unsigned short using below macro */
27 #define HUF_DTABLE_SIZE_U16(maxTableLog) (1 + (1<<maxTableLog))
28 #define HUF_CREATE_STATIC_DTABLE(DTable, maxTableLog) \
29 unsigned short DTable[HUF_DTABLE_SIZE_U16(maxTableLog)] = { maxTableLog }
30
31
32 /******************************************
33 * Error Management
34 ******************************************/
35 #define FSE_LIST_ERRORS(ITEM) \
36 ITEM(FSE_OK_NoError) ITEM(FSE_ERROR_GENERIC) \
37 ITEM(FSE_ERROR_tableLog_tooLarge) ITEM(FSE_ERROR_maxSymbolValue_tooLarge) ITEM(FSE_ERROR_maxSymbolValue_tooSmall) \
38 ITEM(FSE_ERROR_dstSize_tooSmall) ITEM(FSE_ERROR_srcSize_wrong)\
39 ITEM(FSE_ERROR_corruptionDetected) \
40 ITEM(FSE_ERROR_maxCode)
41
42 #define FSE_GENERATE_ENUM(ENUM) ENUM,
43 typedef enum { FSE_LIST_ERRORS(FSE_GENERATE_ENUM) } FSE_errorCodes; /* enum is exposed, to detect & handle specific errors; compare function result to -enum value */
44
45
46 /******************************************
47 * FSE symbol compression API
48 ******************************************/
49 /*
50 This API consists of small unitary functions, which highly benefit from being inlined.
51 You will want to enable link-time-optimization to ensure these functions are properly inlined in your binary.
52 Visual seems to do it automatically.
53 For gcc or clang, you'll need to add -flto flag at compilation and linking stages.
54 If none of these solutions is applicable, include "fse.c" directly.
55 */
56
57 typedef unsigned FSE_CTable; /* don't allocate that. It's just a way to be more restrictive than void* */
58 typedef unsigned FSE_DTable; /* don't allocate that. It's just a way to be more restrictive than void* */
59
60 typedef struct
61 {
62 size_t bitContainer;
63 int bitPos;
64 char* startPtr;
65 char* ptr;
66 char* endPtr;
67 } FSE_CStream_t;
68
69 typedef struct
70 {
71 ptrdiff_t value;
72 const void* stateTable;
73 const void* symbolTT;
74 unsigned stateLog;
75 } FSE_CState_t;
76
77 typedef struct
78 {
79 size_t bitContainer;
80 unsigned bitsConsumed;
81 const char* ptr;
82 const char* start;
83 } FSE_DStream_t;
84
85 typedef struct
86 {
87 size_t state;
88 const void* table; /* precise table may vary, depending on U16 */
89 } FSE_DState_t;
90
91 typedef enum { FSE_DStream_unfinished = 0,
92 FSE_DStream_endOfBuffer = 1,
93 FSE_DStream_completed = 2,
94 FSE_DStream_tooFar = 3 } FSE_DStream_status; /* result of FSE_reloadDStream() */
95 /* 1,2,4,8 would be better for bitmap combinations, but slows down performance a bit ... ?! */
96
97
98 /****************************************************************
99 * Tuning parameters
100 ****************************************************************/
101 /* MEMORY_USAGE :
102 * Memory usage formula : N->2^N Bytes (examples : 10 -> 1KB; 12 -> 4KB ; 16 -> 64KB; 20 -> 1MB; etc.)
103 * Increasing memory usage improves compression ratio
104 * Reduced memory usage can improve speed, due to cache effect
105 * Recommended max value is 14, for 16KB, which nicely fits into Intel x86 L1 cache */
106 #define FSE_MAX_MEMORY_USAGE 14
107 #define FSE_DEFAULT_MEMORY_USAGE 13
108
109 /* FSE_MAX_SYMBOL_VALUE :
110 * Maximum symbol value authorized.
111 * Required for proper stack allocation */
112 #define FSE_MAX_SYMBOL_VALUE 255
113
114
115 /****************************************************************
116 * template functions type & suffix
117 ****************************************************************/
118 #define FSE_FUNCTION_TYPE BYTE
119 #define FSE_FUNCTION_EXTENSION
120
121
122 /****************************************************************
123 * Byte symbol type
124 ****************************************************************/
125 typedef struct
126 {
127 unsigned short newState;
128 unsigned char symbol;
129 unsigned char nbBits;
130 } FSE_decode_t; /* size == U32 */
131
132
133
134 /****************************************************************
135 * Compiler specifics
136 ****************************************************************/
137 #ifdef _MSC_VER /* Visual Studio */
138 # define FORCE_INLINE static __forceinline
139 # include <intrin.h> /* For Visual 2005 */
140 # pragma warning(disable : 4127) /* disable: C4127: conditional expression is constant */
141 # pragma warning(disable : 4214) /* disable: C4214: non-int bitfields */
142 #else
143 # define GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__)
144 # if defined (__cplusplus) || defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L /* C99 */
145 # ifdef __GNUC__
146 # define FORCE_INLINE static inline __attribute__((always_inline))
147 # else
148 # define FORCE_INLINE static inline
149 # endif
150 # else
151 # define FORCE_INLINE static
152 # endif /* __STDC_VERSION__ */
153 #endif
154
155
156 /****************************************************************
157 * Includes
158 ****************************************************************/
159 #include <stdlib.h> /* malloc, free, qsort */
160 #include <string.h> /* memcpy, memset */
161 #include <stdio.h> /* printf (debug) */
162
163
164 #ifndef MEM_ACCESS_MODULE
165 #define MEM_ACCESS_MODULE
166 /****************************************************************
167 * Basic Types
168 *****************************************************************/
169 #if defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L /* C99 */
170 # include <stdint.h>
171 typedef uint8_t BYTE;
172 typedef uint16_t U16;
173 typedef int16_t S16;
174 typedef uint32_t U32;
175 typedef int32_t S32;
176 typedef uint64_t U64;
177 typedef int64_t S64;
178 #else
179 typedef unsigned char BYTE;
180 typedef unsigned short U16;
181 typedef signed short S16;
182 typedef unsigned int U32;
183 typedef signed int S32;
184 typedef unsigned long long U64;
185 typedef signed long long S64;
186 #endif
187
188 #endif /* MEM_ACCESS_MODULE */
189
190 /****************************************************************
191 * Memory I/O
192 *****************************************************************/
193 /* FSE_FORCE_MEMORY_ACCESS
194 * By default, access to unaligned memory is controlled by `memcpy()`, which is safe and portable.
195 * Unfortunately, on some target/compiler combinations, the generated assembly is sub-optimal.
196 * The below switch allow to select different access method for improved performance.
197 * Method 0 (default) : use `memcpy()`. Safe and portable.
198 * Method 1 : `__packed` statement. It depends on compiler extension (ie, not portable).
199 * This method is safe if your compiler supports it, and *generally* as fast or faster than `memcpy`.
200 * Method 2 : direct access. This method is portable but violate C standard.
201 * It can generate buggy code on targets generating assembly depending on alignment.
202 * But in some circumstances, it's the only known way to get the most performance (ie GCC + ARMv6)
203 * See http://fastcompression.blogspot.fr/2015/08/accessing-unaligned-memory.html for details.
204 * Prefer these methods in priority order (0 > 1 > 2)
205 */
206 #ifndef FSE_FORCE_MEMORY_ACCESS /* can be defined externally, on command line for example */
207 # 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__) )
208 # define FSE_FORCE_MEMORY_ACCESS 2
209 # elif (defined(__INTEL_COMPILER) && !defined(WIN32)) || \
210 (defined(__GNUC__) && ( defined(__ARM_ARCH_7__) || defined(__ARM_ARCH_7A__) || defined(__ARM_ARCH_7R__) || defined(__ARM_ARCH_7M__) || defined(__ARM_ARCH_7S__) ))
211 # define FSE_FORCE_MEMORY_ACCESS 1
212 # endif
213 #endif
214
215
FSE_32bits(void)216 static unsigned FSE_32bits(void)
217 {
218 return sizeof(void*)==4;
219 }
220
FSE_isLittleEndian(void)221 static unsigned FSE_isLittleEndian(void)
222 {
223 const union { U32 i; BYTE c[4]; } one = { 1 }; /* don't use static : performance detrimental */
224 return one.c[0];
225 }
226
227 #if defined(FSE_FORCE_MEMORY_ACCESS) && (FSE_FORCE_MEMORY_ACCESS==2)
228
FSE_read16(const void * memPtr)229 static U16 FSE_read16(const void* memPtr) { return *(const U16*) memPtr; }
FSE_read32(const void * memPtr)230 static U32 FSE_read32(const void* memPtr) { return *(const U32*) memPtr; }
FSE_read64(const void * memPtr)231 static U64 FSE_read64(const void* memPtr) { return *(const U64*) memPtr; }
232
233 #elif defined(FSE_FORCE_MEMORY_ACCESS) && (FSE_FORCE_MEMORY_ACCESS==1)
234
235 /* __pack instructions are safer, but compiler specific, hence potentially problematic for some compilers */
236 /* currently only defined for gcc and icc */
237 typedef union { U16 u16; U32 u32; U64 u64; } __attribute__((packed)) unalign;
238
FSE_read16(const void * ptr)239 static U16 FSE_read16(const void* ptr) { return ((const unalign*)ptr)->u16; }
FSE_read32(const void * ptr)240 static U32 FSE_read32(const void* ptr) { return ((const unalign*)ptr)->u32; }
FSE_read64(const void * ptr)241 static U64 FSE_read64(const void* ptr) { return ((const unalign*)ptr)->u64; }
242
243 #else
244
FSE_read16(const void * memPtr)245 static U16 FSE_read16(const void* memPtr)
246 {
247 U16 val; memcpy(&val, memPtr, sizeof(val)); return val;
248 }
249
FSE_read32(const void * memPtr)250 static U32 FSE_read32(const void* memPtr)
251 {
252 U32 val; memcpy(&val, memPtr, sizeof(val)); return val;
253 }
254
FSE_read64(const void * memPtr)255 static U64 FSE_read64(const void* memPtr)
256 {
257 U64 val; memcpy(&val, memPtr, sizeof(val)); return val;
258 }
259
260 #endif /* FSE_FORCE_MEMORY_ACCESS */
261
FSE_readLE16(const void * memPtr)262 static U16 FSE_readLE16(const void* memPtr)
263 {
264 if (FSE_isLittleEndian())
265 return FSE_read16(memPtr);
266 else
267 {
268 const BYTE* p = (const BYTE*)memPtr;
269 return (U16)(p[0] + (p[1]<<8));
270 }
271 }
272
FSE_readLE32(const void * memPtr)273 static U32 FSE_readLE32(const void* memPtr)
274 {
275 if (FSE_isLittleEndian())
276 return FSE_read32(memPtr);
277 else
278 {
279 const BYTE* p = (const BYTE*)memPtr;
280 return (U32)((U32)p[0] + ((U32)p[1]<<8) + ((U32)p[2]<<16) + ((U32)p[3]<<24));
281 }
282 }
283
284
FSE_readLE64(const void * memPtr)285 static U64 FSE_readLE64(const void* memPtr)
286 {
287 if (FSE_isLittleEndian())
288 return FSE_read64(memPtr);
289 else
290 {
291 const BYTE* p = (const BYTE*)memPtr;
292 return (U64)((U64)p[0] + ((U64)p[1]<<8) + ((U64)p[2]<<16) + ((U64)p[3]<<24)
293 + ((U64)p[4]<<32) + ((U64)p[5]<<40) + ((U64)p[6]<<48) + ((U64)p[7]<<56));
294 }
295 }
296
FSE_readLEST(const void * memPtr)297 static size_t FSE_readLEST(const void* memPtr)
298 {
299 if (FSE_32bits())
300 return (size_t)FSE_readLE32(memPtr);
301 else
302 return (size_t)FSE_readLE64(memPtr);
303 }
304
305
306
307 /****************************************************************
308 * Constants
309 *****************************************************************/
310 #define FSE_MAX_TABLELOG (FSE_MAX_MEMORY_USAGE-2)
311 #define FSE_MAX_TABLESIZE (1U<<FSE_MAX_TABLELOG)
312 #define FSE_MAXTABLESIZE_MASK (FSE_MAX_TABLESIZE-1)
313 #define FSE_DEFAULT_TABLELOG (FSE_DEFAULT_MEMORY_USAGE-2)
314 #define FSE_MIN_TABLELOG 5
315
316 #define FSE_TABLELOG_ABSOLUTE_MAX 15
317 #if FSE_MAX_TABLELOG > FSE_TABLELOG_ABSOLUTE_MAX
318 #error "FSE_MAX_TABLELOG > FSE_TABLELOG_ABSOLUTE_MAX is not supported"
319 #endif
320
321
322 /****************************************************************
323 * Error Management
324 ****************************************************************/
325 #define FSE_STATIC_ASSERT(c) { enum { FSE_static_assert = 1/(int)(!!(c)) }; } /* use only *after* variable declarations */
326
327
328 /****************************************************************
329 * Complex types
330 ****************************************************************/
331 typedef struct
332 {
333 int deltaFindState;
334 U32 deltaNbBits;
335 } FSE_symbolCompressionTransform; /* total 8 bytes */
336
337 typedef U32 DTable_max_t[FSE_DTABLE_SIZE_U32(FSE_MAX_TABLELOG)];
338
339 /****************************************************************
340 * Internal functions
341 ****************************************************************/
FSE_highbit32(U32 val)342 FORCE_INLINE unsigned FSE_highbit32 (U32 val)
343 {
344 # if defined(_MSC_VER) /* Visual */
345 unsigned long r;
346 _BitScanReverse ( &r, val );
347 return (unsigned) r;
348 # elif defined(__GNUC__) && (GCC_VERSION >= 304) /* GCC Intrinsic */
349 return __builtin_clz (val) ^ 31;
350 # else /* Software version */
351 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 };
352 U32 v = val;
353 unsigned r;
354 v |= v >> 1;
355 v |= v >> 2;
356 v |= v >> 4;
357 v |= v >> 8;
358 v |= v >> 16;
359 r = DeBruijnClz[ (U32) (v * 0x07C4ACDDU) >> 27];
360 return r;
361 # endif
362 }
363
364
365 /****************************************************************
366 * Templates
367 ****************************************************************/
368 /*
369 designed to be included
370 for type-specific functions (template emulation in C)
371 Objective is to write these functions only once, for improved maintenance
372 */
373
374 /* safety checks */
375 #ifndef FSE_FUNCTION_EXTENSION
376 # error "FSE_FUNCTION_EXTENSION must be defined"
377 #endif
378 #ifndef FSE_FUNCTION_TYPE
379 # error "FSE_FUNCTION_TYPE must be defined"
380 #endif
381
382 /* Function names */
383 #define FSE_CAT(X,Y) X##Y
384 #define FSE_FUNCTION_NAME(X,Y) FSE_CAT(X,Y)
385 #define FSE_TYPE_NAME(X,Y) FSE_CAT(X,Y)
386
387
388
FSE_tableStep(U32 tableSize)389 static U32 FSE_tableStep(U32 tableSize) { return (tableSize>>1) + (tableSize>>3) + 3; }
390
391 #define FSE_DECODE_TYPE FSE_decode_t
392
393
394 typedef struct {
395 U16 tableLog;
396 U16 fastMode;
397 } FSE_DTableHeader; /* sizeof U32 */
398
FSE_buildDTable(FSE_DTable * dt,const short * normalizedCounter,unsigned maxSymbolValue,unsigned tableLog)399 static size_t FSE_buildDTable
400 (FSE_DTable* dt, const short* normalizedCounter, unsigned maxSymbolValue, unsigned tableLog)
401 {
402 void* ptr = dt;
403 FSE_DTableHeader* const DTableH = (FSE_DTableHeader*)ptr;
404 FSE_DECODE_TYPE* const tableDecode = (FSE_DECODE_TYPE*)(ptr) + 1; /* because dt is unsigned, 32-bits aligned on 32-bits */
405 const U32 tableSize = 1 << tableLog;
406 const U32 tableMask = tableSize-1;
407 const U32 step = FSE_tableStep(tableSize);
408 U16 symbolNext[FSE_MAX_SYMBOL_VALUE+1];
409 U32 position = 0;
410 U32 highThreshold = tableSize-1;
411 const S16 largeLimit= (S16)(1 << (tableLog-1));
412 U32 noLarge = 1;
413 U32 s;
414
415 /* Sanity Checks */
416 if (maxSymbolValue > FSE_MAX_SYMBOL_VALUE) return (size_t)-FSE_ERROR_maxSymbolValue_tooLarge;
417 if (tableLog > FSE_MAX_TABLELOG) return (size_t)-FSE_ERROR_tableLog_tooLarge;
418
419 /* Init, lay down lowprob symbols */
420 DTableH[0].tableLog = (U16)tableLog;
421 for (s=0; s<=maxSymbolValue; s++)
422 {
423 if (normalizedCounter[s]==-1)
424 {
425 tableDecode[highThreshold--].symbol = (FSE_FUNCTION_TYPE)s;
426 symbolNext[s] = 1;
427 }
428 else
429 {
430 if (normalizedCounter[s] >= largeLimit) noLarge=0;
431 symbolNext[s] = normalizedCounter[s];
432 }
433 }
434
435 /* Spread symbols */
436 for (s=0; s<=maxSymbolValue; s++)
437 {
438 int i;
439 for (i=0; i<normalizedCounter[s]; i++)
440 {
441 tableDecode[position].symbol = (FSE_FUNCTION_TYPE)s;
442 position = (position + step) & tableMask;
443 while (position > highThreshold) position = (position + step) & tableMask; /* lowprob area */
444 }
445 }
446
447 if (position!=0) return (size_t)-FSE_ERROR_GENERIC; /* position must reach all cells once, otherwise normalizedCounter is incorrect */
448
449 /* Build Decoding table */
450 {
451 U32 i;
452 for (i=0; i<tableSize; i++)
453 {
454 FSE_FUNCTION_TYPE symbol = (FSE_FUNCTION_TYPE)(tableDecode[i].symbol);
455 U16 nextState = symbolNext[symbol]++;
456 tableDecode[i].nbBits = (BYTE) (tableLog - FSE_highbit32 ((U32)nextState) );
457 tableDecode[i].newState = (U16) ( (nextState << tableDecode[i].nbBits) - tableSize);
458 }
459 }
460
461 DTableH->fastMode = (U16)noLarge;
462 return 0;
463 }
464
465
466 /******************************************
467 * FSE byte symbol
468 ******************************************/
469 #ifndef FSE_COMMONDEFS_ONLY
470
FSE_isError(size_t code)471 static unsigned FSE_isError(size_t code) { return (code > (size_t)(-FSE_ERROR_maxCode)); }
472
FSE_abs(short a)473 static short FSE_abs(short a)
474 {
475 return a<0? -a : a;
476 }
477
478
479 /****************************************************************
480 * Header bitstream management
481 ****************************************************************/
FSE_readNCount(short * normalizedCounter,unsigned * maxSVPtr,unsigned * tableLogPtr,const void * headerBuffer,size_t hbSize)482 static size_t FSE_readNCount (short* normalizedCounter, unsigned* maxSVPtr, unsigned* tableLogPtr,
483 const void* headerBuffer, size_t hbSize)
484 {
485 const BYTE* const istart = (const BYTE*) headerBuffer;
486 const BYTE* const iend = istart + hbSize;
487 const BYTE* ip = istart;
488 int nbBits;
489 int remaining;
490 int threshold;
491 U32 bitStream;
492 int bitCount;
493 unsigned charnum = 0;
494 int previous0 = 0;
495
496 if (hbSize < 4) return (size_t)-FSE_ERROR_srcSize_wrong;
497 bitStream = FSE_readLE32(ip);
498 nbBits = (bitStream & 0xF) + FSE_MIN_TABLELOG; /* extract tableLog */
499 if (nbBits > FSE_TABLELOG_ABSOLUTE_MAX) return (size_t)-FSE_ERROR_tableLog_tooLarge;
500 bitStream >>= 4;
501 bitCount = 4;
502 *tableLogPtr = nbBits;
503 remaining = (1<<nbBits)+1;
504 threshold = 1<<nbBits;
505 nbBits++;
506
507 while ((remaining>1) && (charnum<=*maxSVPtr))
508 {
509 if (previous0)
510 {
511 unsigned n0 = charnum;
512 while ((bitStream & 0xFFFF) == 0xFFFF)
513 {
514 n0+=24;
515 if (ip < iend-5)
516 {
517 ip+=2;
518 bitStream = FSE_readLE32(ip) >> bitCount;
519 }
520 else
521 {
522 bitStream >>= 16;
523 bitCount+=16;
524 }
525 }
526 while ((bitStream & 3) == 3)
527 {
528 n0+=3;
529 bitStream>>=2;
530 bitCount+=2;
531 }
532 n0 += bitStream & 3;
533 bitCount += 2;
534 if (n0 > *maxSVPtr) return (size_t)-FSE_ERROR_maxSymbolValue_tooSmall;
535 while (charnum < n0) normalizedCounter[charnum++] = 0;
536 if ((ip <= iend-7) || (ip + (bitCount>>3) <= iend-4))
537 {
538 ip += bitCount>>3;
539 bitCount &= 7;
540 bitStream = FSE_readLE32(ip) >> bitCount;
541 }
542 else
543 bitStream >>= 2;
544 }
545 {
546 const short max = (short)((2*threshold-1)-remaining);
547 short count;
548
549 if ((bitStream & (threshold-1)) < (U32)max)
550 {
551 count = (short)(bitStream & (threshold-1));
552 bitCount += nbBits-1;
553 }
554 else
555 {
556 count = (short)(bitStream & (2*threshold-1));
557 if (count >= threshold) count -= max;
558 bitCount += nbBits;
559 }
560
561 count--; /* extra accuracy */
562 remaining -= FSE_abs(count);
563 normalizedCounter[charnum++] = count;
564 previous0 = !count;
565 while (remaining < threshold)
566 {
567 nbBits--;
568 threshold >>= 1;
569 }
570
571 {
572 if ((ip <= iend-7) || (ip + (bitCount>>3) <= iend-4))
573 {
574 ip += bitCount>>3;
575 bitCount &= 7;
576 }
577 else
578 {
579 bitCount -= (int)(8 * (iend - 4 - ip));
580 ip = iend - 4;
581 }
582 bitStream = FSE_readLE32(ip) >> (bitCount & 31);
583 }
584 }
585 }
586 if (remaining != 1) return (size_t)-FSE_ERROR_GENERIC;
587 *maxSVPtr = charnum-1;
588
589 ip += (bitCount+7)>>3;
590 if ((size_t)(ip-istart) > hbSize) return (size_t)-FSE_ERROR_srcSize_wrong;
591 return ip-istart;
592 }
593
594
595 /*********************************************************
596 * Decompression (Byte symbols)
597 *********************************************************/
FSE_buildDTable_rle(FSE_DTable * dt,BYTE symbolValue)598 static size_t FSE_buildDTable_rle (FSE_DTable* dt, BYTE symbolValue)
599 {
600 void* ptr = dt;
601 FSE_DTableHeader* const DTableH = (FSE_DTableHeader*)ptr;
602 FSE_decode_t* const cell = (FSE_decode_t*)(ptr) + 1; /* because dt is unsigned */
603
604 DTableH->tableLog = 0;
605 DTableH->fastMode = 0;
606
607 cell->newState = 0;
608 cell->symbol = symbolValue;
609 cell->nbBits = 0;
610
611 return 0;
612 }
613
614
FSE_buildDTable_raw(FSE_DTable * dt,unsigned nbBits)615 static size_t FSE_buildDTable_raw (FSE_DTable* dt, unsigned nbBits)
616 {
617 void* ptr = dt;
618 FSE_DTableHeader* const DTableH = (FSE_DTableHeader*)ptr;
619 FSE_decode_t* const dinfo = (FSE_decode_t*)(ptr) + 1; /* because dt is unsigned */
620 const unsigned tableSize = 1 << nbBits;
621 const unsigned tableMask = tableSize - 1;
622 const unsigned maxSymbolValue = tableMask;
623 unsigned s;
624
625 /* Sanity checks */
626 if (nbBits < 1) return (size_t)-FSE_ERROR_GENERIC; /* min size */
627
628 /* Build Decoding Table */
629 DTableH->tableLog = (U16)nbBits;
630 DTableH->fastMode = 1;
631 for (s=0; s<=maxSymbolValue; s++)
632 {
633 dinfo[s].newState = 0;
634 dinfo[s].symbol = (BYTE)s;
635 dinfo[s].nbBits = (BYTE)nbBits;
636 }
637
638 return 0;
639 }
640
641
642 /* FSE_initDStream
643 * Initialize a FSE_DStream_t.
644 * srcBuffer must point at the beginning of an FSE block.
645 * The function result is the size of the FSE_block (== srcSize).
646 * If srcSize is too small, the function will return an errorCode;
647 */
FSE_initDStream(FSE_DStream_t * bitD,const void * srcBuffer,size_t srcSize)648 static size_t FSE_initDStream(FSE_DStream_t* bitD, const void* srcBuffer, size_t srcSize)
649 {
650 if (srcSize < 1) return (size_t)-FSE_ERROR_srcSize_wrong;
651
652 if (srcSize >= sizeof(size_t))
653 {
654 U32 contain32;
655 bitD->start = (const char*)srcBuffer;
656 bitD->ptr = (const char*)srcBuffer + srcSize - sizeof(size_t);
657 bitD->bitContainer = FSE_readLEST(bitD->ptr);
658 contain32 = ((const BYTE*)srcBuffer)[srcSize-1];
659 if (contain32 == 0) return (size_t)-FSE_ERROR_GENERIC; /* stop bit not present */
660 bitD->bitsConsumed = 8 - FSE_highbit32(contain32);
661 }
662 else
663 {
664 U32 contain32;
665 bitD->start = (const char*)srcBuffer;
666 bitD->ptr = bitD->start;
667 bitD->bitContainer = *(const BYTE*)(bitD->start);
668 switch(srcSize)
669 {
670 case 7: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[6]) << (sizeof(size_t)*8 - 16);
671 /* fallthrough */
672 case 6: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[5]) << (sizeof(size_t)*8 - 24);
673 /* fallthrough */
674 case 5: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[4]) << (sizeof(size_t)*8 - 32);
675 /* fallthrough */
676 case 4: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[3]) << 24;
677 /* fallthrough */
678 case 3: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[2]) << 16;
679 /* fallthrough */
680 case 2: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[1]) << 8;
681 /* fallthrough */
682 default:;
683 }
684 contain32 = ((const BYTE*)srcBuffer)[srcSize-1];
685 if (contain32 == 0) return (size_t)-FSE_ERROR_GENERIC; /* stop bit not present */
686 bitD->bitsConsumed = 8 - FSE_highbit32(contain32);
687 bitD->bitsConsumed += (U32)(sizeof(size_t) - srcSize)*8;
688 }
689
690 return srcSize;
691 }
692
693
694 /*!FSE_lookBits
695 * Provides next n bits from the bitContainer.
696 * bitContainer is not modified (bits are still present for next read/look)
697 * On 32-bits, maxNbBits==25
698 * On 64-bits, maxNbBits==57
699 * return : value extracted.
700 */
FSE_lookBits(FSE_DStream_t * bitD,U32 nbBits)701 static size_t FSE_lookBits(FSE_DStream_t* bitD, U32 nbBits)
702 {
703 const U32 bitMask = sizeof(bitD->bitContainer)*8 - 1;
704 return ((bitD->bitContainer << (bitD->bitsConsumed & bitMask)) >> 1) >> ((bitMask-nbBits) & bitMask);
705 }
706
FSE_lookBitsFast(FSE_DStream_t * bitD,U32 nbBits)707 static size_t FSE_lookBitsFast(FSE_DStream_t* bitD, U32 nbBits) /* only if nbBits >= 1 !! */
708 {
709 const U32 bitMask = sizeof(bitD->bitContainer)*8 - 1;
710 return (bitD->bitContainer << (bitD->bitsConsumed & bitMask)) >> (((bitMask+1)-nbBits) & bitMask);
711 }
712
FSE_skipBits(FSE_DStream_t * bitD,U32 nbBits)713 static void FSE_skipBits(FSE_DStream_t* bitD, U32 nbBits)
714 {
715 bitD->bitsConsumed += nbBits;
716 }
717
718
719 /*!FSE_readBits
720 * Read next n bits from the bitContainer.
721 * On 32-bits, don't read more than maxNbBits==25
722 * On 64-bits, don't read more than maxNbBits==57
723 * Use the fast variant *only* if n >= 1.
724 * return : value extracted.
725 */
FSE_readBits(FSE_DStream_t * bitD,U32 nbBits)726 static size_t FSE_readBits(FSE_DStream_t* bitD, U32 nbBits)
727 {
728 size_t value = FSE_lookBits(bitD, nbBits);
729 FSE_skipBits(bitD, nbBits);
730 return value;
731 }
732
FSE_readBitsFast(FSE_DStream_t * bitD,U32 nbBits)733 static size_t FSE_readBitsFast(FSE_DStream_t* bitD, U32 nbBits) /* only if nbBits >= 1 !! */
734 {
735 size_t value = FSE_lookBitsFast(bitD, nbBits);
736 FSE_skipBits(bitD, nbBits);
737 return value;
738 }
739
FSE_reloadDStream(FSE_DStream_t * bitD)740 static unsigned FSE_reloadDStream(FSE_DStream_t* bitD)
741 {
742 if (bitD->bitsConsumed > (sizeof(bitD->bitContainer)*8)) /* should never happen */
743 return FSE_DStream_tooFar;
744
745 if (bitD->ptr >= bitD->start + sizeof(bitD->bitContainer))
746 {
747 bitD->ptr -= bitD->bitsConsumed >> 3;
748 bitD->bitsConsumed &= 7;
749 bitD->bitContainer = FSE_readLEST(bitD->ptr);
750 return FSE_DStream_unfinished;
751 }
752 if (bitD->ptr == bitD->start)
753 {
754 if (bitD->bitsConsumed < sizeof(bitD->bitContainer)*8) return FSE_DStream_endOfBuffer;
755 return FSE_DStream_completed;
756 }
757 {
758 U32 nbBytes = bitD->bitsConsumed >> 3;
759 U32 result = FSE_DStream_unfinished;
760 if (bitD->ptr - nbBytes < bitD->start)
761 {
762 nbBytes = (U32)(bitD->ptr - bitD->start); /* ptr > start */
763 result = FSE_DStream_endOfBuffer;
764 }
765 bitD->ptr -= nbBytes;
766 bitD->bitsConsumed -= nbBytes*8;
767 bitD->bitContainer = FSE_readLEST(bitD->ptr); /* reminder : srcSize > sizeof(bitD) */
768 return result;
769 }
770 }
771
772
FSE_initDState(FSE_DState_t * DStatePtr,FSE_DStream_t * bitD,const FSE_DTable * dt)773 static void FSE_initDState(FSE_DState_t* DStatePtr, FSE_DStream_t* bitD, const FSE_DTable* dt)
774 {
775 const void* ptr = dt;
776 const FSE_DTableHeader* const DTableH = (const FSE_DTableHeader*)ptr;
777 DStatePtr->state = FSE_readBits(bitD, DTableH->tableLog);
778 FSE_reloadDStream(bitD);
779 DStatePtr->table = dt + 1;
780 }
781
FSE_decodeSymbol(FSE_DState_t * DStatePtr,FSE_DStream_t * bitD)782 static BYTE FSE_decodeSymbol(FSE_DState_t* DStatePtr, FSE_DStream_t* bitD)
783 {
784 const FSE_decode_t DInfo = ((const FSE_decode_t*)(DStatePtr->table))[DStatePtr->state];
785 const U32 nbBits = DInfo.nbBits;
786 BYTE symbol = DInfo.symbol;
787 size_t lowBits = FSE_readBits(bitD, nbBits);
788
789 DStatePtr->state = DInfo.newState + lowBits;
790 return symbol;
791 }
792
FSE_decodeSymbolFast(FSE_DState_t * DStatePtr,FSE_DStream_t * bitD)793 static BYTE FSE_decodeSymbolFast(FSE_DState_t* DStatePtr, FSE_DStream_t* bitD)
794 {
795 const FSE_decode_t DInfo = ((const FSE_decode_t*)(DStatePtr->table))[DStatePtr->state];
796 const U32 nbBits = DInfo.nbBits;
797 BYTE symbol = DInfo.symbol;
798 size_t lowBits = FSE_readBitsFast(bitD, nbBits);
799
800 DStatePtr->state = DInfo.newState + lowBits;
801 return symbol;
802 }
803
804 /* FSE_endOfDStream
805 Tells if bitD has reached end of bitStream or not */
806
FSE_endOfDStream(const FSE_DStream_t * bitD)807 static unsigned FSE_endOfDStream(const FSE_DStream_t* bitD)
808 {
809 return ((bitD->ptr == bitD->start) && (bitD->bitsConsumed == sizeof(bitD->bitContainer)*8));
810 }
811
FSE_endOfDState(const FSE_DState_t * DStatePtr)812 static unsigned FSE_endOfDState(const FSE_DState_t* DStatePtr)
813 {
814 return DStatePtr->state == 0;
815 }
816
817
FSE_decompress_usingDTable_generic(void * dst,size_t maxDstSize,const void * cSrc,size_t cSrcSize,const FSE_DTable * dt,const unsigned fast)818 FORCE_INLINE size_t FSE_decompress_usingDTable_generic(
819 void* dst, size_t maxDstSize,
820 const void* cSrc, size_t cSrcSize,
821 const FSE_DTable* dt, const unsigned fast)
822 {
823 BYTE* const ostart = (BYTE*) dst;
824 BYTE* op = ostart;
825 BYTE* const omax = op + maxDstSize;
826 BYTE* const olimit = omax-3;
827
828 FSE_DStream_t bitD;
829 FSE_DState_t state1;
830 FSE_DState_t state2;
831 size_t errorCode;
832
833 /* Init */
834 errorCode = FSE_initDStream(&bitD, cSrc, cSrcSize); /* replaced last arg by maxCompressed Size */
835 if (FSE_isError(errorCode)) return errorCode;
836
837 FSE_initDState(&state1, &bitD, dt);
838 FSE_initDState(&state2, &bitD, dt);
839
840 #define FSE_GETSYMBOL(statePtr) fast ? FSE_decodeSymbolFast(statePtr, &bitD) : FSE_decodeSymbol(statePtr, &bitD)
841
842 /* 4 symbols per loop */
843 for ( ; (FSE_reloadDStream(&bitD)==FSE_DStream_unfinished) && (op<olimit) ; op+=4)
844 {
845 op[0] = FSE_GETSYMBOL(&state1);
846
847 if (FSE_MAX_TABLELOG*2+7 > sizeof(bitD.bitContainer)*8) /* This test must be static */
848 FSE_reloadDStream(&bitD);
849
850 op[1] = FSE_GETSYMBOL(&state2);
851
852 if (FSE_MAX_TABLELOG*4+7 > sizeof(bitD.bitContainer)*8) /* This test must be static */
853 { if (FSE_reloadDStream(&bitD) > FSE_DStream_unfinished) { op+=2; break; } }
854
855 op[2] = FSE_GETSYMBOL(&state1);
856
857 if (FSE_MAX_TABLELOG*2+7 > sizeof(bitD.bitContainer)*8) /* This test must be static */
858 FSE_reloadDStream(&bitD);
859
860 op[3] = FSE_GETSYMBOL(&state2);
861 }
862
863 /* tail */
864 /* note : FSE_reloadDStream(&bitD) >= FSE_DStream_partiallyFilled; Ends at exactly FSE_DStream_completed */
865 while (1)
866 {
867 if ( (FSE_reloadDStream(&bitD)>FSE_DStream_completed) || (op==omax) || (FSE_endOfDStream(&bitD) && (fast || FSE_endOfDState(&state1))) )
868 break;
869
870 *op++ = FSE_GETSYMBOL(&state1);
871
872 if ( (FSE_reloadDStream(&bitD)>FSE_DStream_completed) || (op==omax) || (FSE_endOfDStream(&bitD) && (fast || FSE_endOfDState(&state2))) )
873 break;
874
875 *op++ = FSE_GETSYMBOL(&state2);
876 }
877
878 /* end ? */
879 if (FSE_endOfDStream(&bitD) && FSE_endOfDState(&state1) && FSE_endOfDState(&state2))
880 return op-ostart;
881
882 if (op==omax) return (size_t)-FSE_ERROR_dstSize_tooSmall; /* dst buffer is full, but cSrc unfinished */
883
884 return (size_t)-FSE_ERROR_corruptionDetected;
885 }
886
887
FSE_decompress_usingDTable(void * dst,size_t originalSize,const void * cSrc,size_t cSrcSize,const FSE_DTable * dt)888 static size_t FSE_decompress_usingDTable(void* dst, size_t originalSize,
889 const void* cSrc, size_t cSrcSize,
890 const FSE_DTable* dt)
891 {
892 FSE_DTableHeader DTableH;
893 memcpy(&DTableH, dt, sizeof(DTableH)); /* memcpy() into local variable, to avoid strict aliasing warning */
894
895 /* select fast mode (static) */
896 if (DTableH.fastMode) return FSE_decompress_usingDTable_generic(dst, originalSize, cSrc, cSrcSize, dt, 1);
897 return FSE_decompress_usingDTable_generic(dst, originalSize, cSrc, cSrcSize, dt, 0);
898 }
899
900
FSE_decompress(void * dst,size_t maxDstSize,const void * cSrc,size_t cSrcSize)901 static size_t FSE_decompress(void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize)
902 {
903 const BYTE* const istart = (const BYTE*)cSrc;
904 const BYTE* ip = istart;
905 short counting[FSE_MAX_SYMBOL_VALUE+1];
906 DTable_max_t dt; /* Static analyzer seems unable to understand this table will be properly initialized later */
907 unsigned tableLog;
908 unsigned maxSymbolValue = FSE_MAX_SYMBOL_VALUE;
909 size_t errorCode;
910
911 if (cSrcSize<2) return (size_t)-FSE_ERROR_srcSize_wrong; /* too small input size */
912
913 /* normal FSE decoding mode */
914 errorCode = FSE_readNCount (counting, &maxSymbolValue, &tableLog, istart, cSrcSize);
915 if (FSE_isError(errorCode)) return errorCode;
916 if (errorCode >= cSrcSize) return (size_t)-FSE_ERROR_srcSize_wrong; /* too small input size */
917 ip += errorCode;
918 cSrcSize -= errorCode;
919
920 errorCode = FSE_buildDTable (dt, counting, maxSymbolValue, tableLog);
921 if (FSE_isError(errorCode)) return errorCode;
922
923 /* always return, even if it is an error code */
924 return FSE_decompress_usingDTable (dst, maxDstSize, ip, cSrcSize, dt);
925 }
926
927
928
929 /* *******************************************************
930 * Huff0 : Huffman block compression
931 *********************************************************/
932 #define HUF_MAX_SYMBOL_VALUE 255
933 #define HUF_DEFAULT_TABLELOG 12 /* used by default, when not specified */
934 #define HUF_MAX_TABLELOG 12 /* max possible tableLog; for allocation purpose; can be modified */
935 #define HUF_ABSOLUTEMAX_TABLELOG 16 /* absolute limit of HUF_MAX_TABLELOG. Beyond that value, code does not work */
936 #if (HUF_MAX_TABLELOG > HUF_ABSOLUTEMAX_TABLELOG)
937 # error "HUF_MAX_TABLELOG is too large !"
938 #endif
939
940 typedef struct HUF_CElt_s {
941 U16 val;
942 BYTE nbBits;
943 } HUF_CElt ;
944
945 typedef struct nodeElt_s {
946 U32 count;
947 U16 parent;
948 BYTE byte;
949 BYTE nbBits;
950 } nodeElt;
951
952
953 /* *******************************************************
954 * Huff0 : Huffman block decompression
955 *********************************************************/
956 typedef struct {
957 BYTE byte;
958 BYTE nbBits;
959 } HUF_DElt;
960
HUF_readDTable(U16 * DTable,const void * src,size_t srcSize)961 static size_t HUF_readDTable (U16* DTable, const void* src, size_t srcSize)
962 {
963 BYTE huffWeight[HUF_MAX_SYMBOL_VALUE + 1];
964 U32 rankVal[HUF_ABSOLUTEMAX_TABLELOG + 1]; /* large enough for values from 0 to 16 */
965 U32 weightTotal;
966 U32 maxBits;
967 const BYTE* ip = (const BYTE*) src;
968 size_t iSize;
969 size_t oSize;
970 U32 n;
971 U32 nextRankStart;
972 void* ptr = DTable+1;
973 HUF_DElt* const dt = (HUF_DElt*)ptr;
974
975 if (!srcSize) return (size_t)-FSE_ERROR_srcSize_wrong;
976 iSize = ip[0];
977
978 FSE_STATIC_ASSERT(sizeof(HUF_DElt) == sizeof(U16)); /* if compilation fails here, assertion is false */
979 //memset(huffWeight, 0, sizeof(huffWeight)); /* should not be necessary, but some analyzer complain ... */
980 if (iSize >= 128) /* special header */
981 {
982 if (iSize >= (242)) /* RLE */
983 {
984 static int l[14] = { 1, 2, 3, 4, 7, 8, 15, 16, 31, 32, 63, 64, 127, 128 };
985 oSize = l[iSize-242];
986 memset(huffWeight, 1, sizeof(huffWeight));
987 iSize = 0;
988 }
989 else /* Incompressible */
990 {
991 oSize = iSize - 127;
992 iSize = ((oSize+1)/2);
993 if (iSize+1 > srcSize) return (size_t)-FSE_ERROR_srcSize_wrong;
994 ip += 1;
995 for (n=0; n<oSize; n+=2)
996 {
997 huffWeight[n] = ip[n/2] >> 4;
998 huffWeight[n+1] = ip[n/2] & 15;
999 }
1000 }
1001 }
1002 else /* header compressed with FSE (normal case) */
1003 {
1004 if (iSize+1 > srcSize) return (size_t)-FSE_ERROR_srcSize_wrong;
1005 oSize = FSE_decompress(huffWeight, HUF_MAX_SYMBOL_VALUE, ip+1, iSize); /* max 255 values decoded, last one is implied */
1006 if (FSE_isError(oSize)) return oSize;
1007 }
1008
1009 /* collect weight stats */
1010 memset(rankVal, 0, sizeof(rankVal));
1011 weightTotal = 0;
1012 for (n=0; n<oSize; n++)
1013 {
1014 if (huffWeight[n] >= HUF_ABSOLUTEMAX_TABLELOG) return (size_t)-FSE_ERROR_corruptionDetected;
1015 rankVal[huffWeight[n]]++;
1016 weightTotal += (1 << huffWeight[n]) >> 1;
1017 }
1018 if (weightTotal == 0) return (size_t)-FSE_ERROR_corruptionDetected;
1019
1020 /* get last non-null symbol weight (implied, total must be 2^n) */
1021 maxBits = FSE_highbit32(weightTotal) + 1;
1022 if (maxBits > DTable[0]) return (size_t)-FSE_ERROR_tableLog_tooLarge; /* DTable is too small */
1023 DTable[0] = (U16)maxBits;
1024 {
1025 U32 total = 1 << maxBits;
1026 U32 rest = total - weightTotal;
1027 U32 verif = 1 << FSE_highbit32(rest);
1028 U32 lastWeight = FSE_highbit32(rest) + 1;
1029 if (verif != rest) return (size_t)-FSE_ERROR_corruptionDetected; /* last value must be a clean power of 2 */
1030 huffWeight[oSize] = (BYTE)lastWeight;
1031 rankVal[lastWeight]++;
1032 }
1033
1034 /* check tree construction validity */
1035 if ((rankVal[1] < 2) || (rankVal[1] & 1)) return (size_t)-FSE_ERROR_corruptionDetected; /* by construction : at least 2 elts of rank 1, must be even */
1036
1037 /* Prepare ranks */
1038 nextRankStart = 0;
1039 for (n=1; n<=maxBits; n++)
1040 {
1041 U32 current = nextRankStart;
1042 nextRankStart += (rankVal[n] << (n-1));
1043 rankVal[n] = current;
1044 }
1045
1046 /* fill DTable */
1047 for (n=0; n<=oSize; n++)
1048 {
1049 const U32 w = huffWeight[n];
1050 const U32 length = (1 << w) >> 1;
1051 U32 i;
1052 HUF_DElt D;
1053 D.byte = (BYTE)n; D.nbBits = (BYTE)(maxBits + 1 - w);
1054 for (i = rankVal[w]; i < rankVal[w] + length; i++)
1055 dt[i] = D;
1056 rankVal[w] += length;
1057 }
1058
1059 return iSize+1;
1060 }
1061
1062
HUF_decodeSymbol(FSE_DStream_t * Dstream,const HUF_DElt * dt,const U32 dtLog)1063 static BYTE HUF_decodeSymbol(FSE_DStream_t* Dstream, const HUF_DElt* dt, const U32 dtLog)
1064 {
1065 const size_t val = FSE_lookBitsFast(Dstream, dtLog); /* note : dtLog >= 1 */
1066 const BYTE c = dt[val].byte;
1067 FSE_skipBits(Dstream, dt[val].nbBits);
1068 return c;
1069 }
1070
HUF_decompress_usingDTable(void * dst,size_t maxDstSize,const void * cSrc,size_t cSrcSize,const U16 * DTable)1071 static size_t HUF_decompress_usingDTable( /* -3% slower when non static */
1072 void* dst, size_t maxDstSize,
1073 const void* cSrc, size_t cSrcSize,
1074 const U16* DTable)
1075 {
1076 if (cSrcSize < 6) return (size_t)-FSE_ERROR_srcSize_wrong;
1077 {
1078 BYTE* const ostart = (BYTE*) dst;
1079 BYTE* op = ostart;
1080 BYTE* const omax = op + maxDstSize;
1081 BYTE* const olimit = maxDstSize < 15 ? op : omax-15;
1082
1083 const void* ptr = DTable;
1084 const HUF_DElt* const dt = (const HUF_DElt*)(ptr)+1;
1085 const U32 dtLog = DTable[0];
1086 size_t errorCode;
1087 U32 reloadStatus;
1088
1089 /* Init */
1090
1091 const U16* jumpTable = (const U16*)cSrc;
1092 const size_t length1 = FSE_readLE16(jumpTable);
1093 const size_t length2 = FSE_readLE16(jumpTable+1);
1094 const size_t length3 = FSE_readLE16(jumpTable+2);
1095 const size_t length4 = cSrcSize - 6 - length1 - length2 - length3; /* check coherency !! */
1096 const char* const start1 = (const char*)(cSrc) + 6;
1097 const char* const start2 = start1 + length1;
1098 const char* const start3 = start2 + length2;
1099 const char* const start4 = start3 + length3;
1100 FSE_DStream_t bitD1, bitD2, bitD3, bitD4;
1101
1102 if (length1+length2+length3+6 >= cSrcSize) return (size_t)-FSE_ERROR_srcSize_wrong;
1103
1104 errorCode = FSE_initDStream(&bitD1, start1, length1);
1105 if (FSE_isError(errorCode)) return errorCode;
1106 errorCode = FSE_initDStream(&bitD2, start2, length2);
1107 if (FSE_isError(errorCode)) return errorCode;
1108 errorCode = FSE_initDStream(&bitD3, start3, length3);
1109 if (FSE_isError(errorCode)) return errorCode;
1110 errorCode = FSE_initDStream(&bitD4, start4, length4);
1111 if (FSE_isError(errorCode)) return errorCode;
1112
1113 reloadStatus=FSE_reloadDStream(&bitD2);
1114
1115 /* 16 symbols per loop */
1116 for ( ; (reloadStatus<FSE_DStream_completed) && (op<olimit); /* D2-3-4 are supposed to be synchronized and finish together */
1117 op+=16, reloadStatus = FSE_reloadDStream(&bitD2) | FSE_reloadDStream(&bitD3) | FSE_reloadDStream(&bitD4), FSE_reloadDStream(&bitD1))
1118 {
1119 #define HUF_DECODE_SYMBOL_0(n, Dstream) \
1120 op[n] = HUF_decodeSymbol(&Dstream, dt, dtLog);
1121
1122 #define HUF_DECODE_SYMBOL_1(n, Dstream) \
1123 op[n] = HUF_decodeSymbol(&Dstream, dt, dtLog); \
1124 if (FSE_32bits() && (HUF_MAX_TABLELOG>12)) FSE_reloadDStream(&Dstream)
1125
1126 #define HUF_DECODE_SYMBOL_2(n, Dstream) \
1127 op[n] = HUF_decodeSymbol(&Dstream, dt, dtLog); \
1128 if (FSE_32bits()) FSE_reloadDStream(&Dstream)
1129
1130 HUF_DECODE_SYMBOL_1( 0, bitD1);
1131 HUF_DECODE_SYMBOL_1( 1, bitD2);
1132 HUF_DECODE_SYMBOL_1( 2, bitD3);
1133 HUF_DECODE_SYMBOL_1( 3, bitD4);
1134 HUF_DECODE_SYMBOL_2( 4, bitD1);
1135 HUF_DECODE_SYMBOL_2( 5, bitD2);
1136 HUF_DECODE_SYMBOL_2( 6, bitD3);
1137 HUF_DECODE_SYMBOL_2( 7, bitD4);
1138 HUF_DECODE_SYMBOL_1( 8, bitD1);
1139 HUF_DECODE_SYMBOL_1( 9, bitD2);
1140 HUF_DECODE_SYMBOL_1(10, bitD3);
1141 HUF_DECODE_SYMBOL_1(11, bitD4);
1142 HUF_DECODE_SYMBOL_0(12, bitD1);
1143 HUF_DECODE_SYMBOL_0(13, bitD2);
1144 HUF_DECODE_SYMBOL_0(14, bitD3);
1145 HUF_DECODE_SYMBOL_0(15, bitD4);
1146 }
1147
1148 if (reloadStatus!=FSE_DStream_completed) /* not complete : some bitStream might be FSE_DStream_unfinished */
1149 return (size_t)-FSE_ERROR_corruptionDetected;
1150
1151 /* tail */
1152 {
1153 /* bitTail = bitD1; */ /* *much* slower : -20% !??! */
1154 FSE_DStream_t bitTail;
1155 bitTail.ptr = bitD1.ptr;
1156 bitTail.bitsConsumed = bitD1.bitsConsumed;
1157 bitTail.bitContainer = bitD1.bitContainer; /* required in case of FSE_DStream_endOfBuffer */
1158 bitTail.start = start1;
1159 for ( ; (FSE_reloadDStream(&bitTail) < FSE_DStream_completed) && (op<omax) ; op++)
1160 {
1161 HUF_DECODE_SYMBOL_0(0, bitTail);
1162 }
1163
1164 if (FSE_endOfDStream(&bitTail))
1165 return op-ostart;
1166 }
1167
1168 if (op==omax) return (size_t)-FSE_ERROR_dstSize_tooSmall; /* dst buffer is full, but cSrc unfinished */
1169
1170 return (size_t)-FSE_ERROR_corruptionDetected;
1171 }
1172 }
1173
1174
HUF_decompress(void * dst,size_t maxDstSize,const void * cSrc,size_t cSrcSize)1175 static size_t HUF_decompress (void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize)
1176 {
1177 HUF_CREATE_STATIC_DTABLE(DTable, HUF_MAX_TABLELOG);
1178 const BYTE* ip = (const BYTE*) cSrc;
1179 size_t errorCode;
1180
1181 errorCode = HUF_readDTable (DTable, cSrc, cSrcSize);
1182 if (FSE_isError(errorCode)) return errorCode;
1183 if (errorCode >= cSrcSize) return (size_t)-FSE_ERROR_srcSize_wrong;
1184 ip += errorCode;
1185 cSrcSize -= errorCode;
1186
1187 return HUF_decompress_usingDTable (dst, maxDstSize, ip, cSrcSize, DTable);
1188 }
1189
1190
1191 #endif /* FSE_COMMONDEFS_ONLY */
1192
1193 /*
1194 zstd - standard compression library
1195 Copyright (C) 2014-2015, Yann Collet.
1196
1197 BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
1198
1199 Redistribution and use in source and binary forms, with or without
1200 modification, are permitted provided that the following conditions are
1201 met:
1202 * Redistributions of source code must retain the above copyright
1203 notice, this list of conditions and the following disclaimer.
1204 * Redistributions in binary form must reproduce the above
1205 copyright notice, this list of conditions and the following disclaimer
1206 in the documentation and/or other materials provided with the
1207 distribution.
1208 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
1209 "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
1210 LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
1211 A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
1212 OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
1213 SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
1214 LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
1215 DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
1216 THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
1217 (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
1218 OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1219
1220 You can contact the author at :
1221 - zstd source repository : https://github.com/Cyan4973/zstd
1222 - ztsd public forum : https://groups.google.com/forum/#!forum/lz4c
1223 */
1224
1225 /****************************************************************
1226 * Tuning parameters
1227 *****************************************************************/
1228 /* MEMORY_USAGE :
1229 * Memory usage formula : N->2^N Bytes (examples : 10 -> 1KB; 12 -> 4KB ; 16 -> 64KB; 20 -> 1MB; etc.)
1230 * Increasing memory usage improves compression ratio
1231 * Reduced memory usage can improve speed, due to cache effect */
1232 #define ZSTD_MEMORY_USAGE 17
1233
1234
1235 /**************************************
1236 CPU Feature Detection
1237 **************************************/
1238 /*
1239 * Automated efficient unaligned memory access detection
1240 * Based on known hardware architectures
1241 * This list will be updated thanks to feedbacks
1242 */
1243 #if defined(CPU_HAS_EFFICIENT_UNALIGNED_MEMORY_ACCESS) \
1244 || defined(__ARM_FEATURE_UNALIGNED) \
1245 || defined(__i386__) || defined(__x86_64__) \
1246 || defined(_M_IX86) || defined(_M_X64) \
1247 || defined(__ARM_ARCH_7__) || defined(__ARM_ARCH_8__) \
1248 || (defined(_M_ARM) && (_M_ARM >= 7))
1249 # define ZSTD_UNALIGNED_ACCESS 1
1250 #else
1251 # define ZSTD_UNALIGNED_ACCESS 0
1252 #endif
1253
1254
1255 /********************************************************
1256 * Includes
1257 *********************************************************/
1258 #include <stdlib.h> /* calloc */
1259 #include <string.h> /* memcpy, memmove */
1260 #include <stdio.h> /* debug : printf */
1261
1262
1263 /********************************************************
1264 * Compiler specifics
1265 *********************************************************/
1266 #ifdef __AVX2__
1267 # include <immintrin.h> /* AVX2 intrinsics */
1268 #endif
1269
1270 #ifdef _MSC_VER /* Visual Studio */
1271 # include <intrin.h> /* For Visual 2005 */
1272 # pragma warning(disable : 4127) /* disable: C4127: conditional expression is constant */
1273 # pragma warning(disable : 4324) /* disable: C4324: padded structure */
1274 #endif
1275
1276
1277 #ifndef MEM_ACCESS_MODULE
1278 #define MEM_ACCESS_MODULE
1279 /********************************************************
1280 * Basic Types
1281 *********************************************************/
1282 #if defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L /* C99 */
1283 # include <stdint.h>
1284 typedef uint8_t BYTE;
1285 typedef uint16_t U16;
1286 typedef int16_t S16;
1287 typedef uint32_t U32;
1288 typedef int32_t S32;
1289 typedef uint64_t U64;
1290 #else
1291 typedef unsigned char BYTE;
1292 typedef unsigned short U16;
1293 typedef signed short S16;
1294 typedef unsigned int U32;
1295 typedef signed int S32;
1296 typedef unsigned long long U64;
1297 #endif
1298
1299 #endif /* MEM_ACCESS_MODULE */
1300
1301
1302 /********************************************************
1303 * Constants
1304 *********************************************************/
1305 static const U32 ZSTD_magicNumber = 0xFD2FB51E; /* 3rd version : seqNb header */
1306
1307 #define HASH_LOG (ZSTD_MEMORY_USAGE - 2)
1308 #define HASH_TABLESIZE (1 << HASH_LOG)
1309 #define HASH_MASK (HASH_TABLESIZE - 1)
1310
1311 #define KNUTH 2654435761
1312
1313 #define BIT7 128
1314 #define BIT6 64
1315 #define BIT5 32
1316 #define BIT4 16
1317
1318 #define KB *(1 <<10)
1319 #define MB *(1 <<20)
1320 #define GB *(1U<<30)
1321
1322 #define BLOCKSIZE (128 KB) /* define, for static allocation */
1323
1324 #define WORKPLACESIZE (BLOCKSIZE*3)
1325 #define MINMATCH 4
1326 #define MLbits 7
1327 #define LLbits 6
1328 #define Offbits 5
1329 #define MaxML ((1<<MLbits )-1)
1330 #define MaxLL ((1<<LLbits )-1)
1331 #define MaxOff ((1<<Offbits)-1)
1332 #define LitFSELog 11
1333 #define MLFSELog 10
1334 #define LLFSELog 10
1335 #define OffFSELog 9
1336 #define MAX(a,b) ((a)<(b)?(b):(a))
1337 #define MaxSeq MAX(MaxLL, MaxML)
1338
1339 #define LITERAL_NOENTROPY 63
1340 #define COMMAND_NOENTROPY 7 /* to remove */
1341
1342 #define ZSTD_CONTENTSIZE_ERROR (0ULL - 2)
1343
1344 static const size_t ZSTD_blockHeaderSize = 3;
1345 static const size_t ZSTD_frameHeaderSize = 4;
1346
1347
1348 /********************************************************
1349 * Memory operations
1350 *********************************************************/
ZSTD_32bits(void)1351 static unsigned ZSTD_32bits(void) { return sizeof(void*)==4; }
1352
ZSTD_isLittleEndian(void)1353 static unsigned ZSTD_isLittleEndian(void)
1354 {
1355 const union { U32 i; BYTE c[4]; } one = { 1 }; /* don't use static : performance detrimental */
1356 return one.c[0];
1357 }
1358
ZSTD_read16(const void * p)1359 static U16 ZSTD_read16(const void* p) { U16 r; memcpy(&r, p, sizeof(r)); return r; }
1360
ZSTD_copy4(void * dst,const void * src)1361 static void ZSTD_copy4(void* dst, const void* src) { memcpy(dst, src, 4); }
1362
ZSTD_copy8(void * dst,const void * src)1363 static void ZSTD_copy8(void* dst, const void* src) { memcpy(dst, src, 8); }
1364
1365 #define COPY8(d,s) { ZSTD_copy8(d,s); d+=8; s+=8; }
1366
ZSTD_wildcopy(void * dst,const void * src,ptrdiff_t length)1367 static void ZSTD_wildcopy(void* dst, const void* src, ptrdiff_t length)
1368 {
1369 const BYTE* ip = (const BYTE*)src;
1370 BYTE* op = (BYTE*)dst;
1371 BYTE* const oend = op + length;
1372 while (op < oend) COPY8(op, ip);
1373 }
1374
ZSTD_readLE16(const void * memPtr)1375 static U16 ZSTD_readLE16(const void* memPtr)
1376 {
1377 if (ZSTD_isLittleEndian()) return ZSTD_read16(memPtr);
1378 else
1379 {
1380 const BYTE* p = (const BYTE*)memPtr;
1381 return (U16)((U16)p[0] + ((U16)p[1]<<8));
1382 }
1383 }
1384
ZSTD_readLE24(const void * memPtr)1385 static U32 ZSTD_readLE24(const void* memPtr)
1386 {
1387 return ZSTD_readLE16(memPtr) + (((const BYTE*)memPtr)[2] << 16);
1388 }
1389
ZSTD_readBE32(const void * memPtr)1390 static U32 ZSTD_readBE32(const void* memPtr)
1391 {
1392 const BYTE* p = (const BYTE*)memPtr;
1393 return (U32)(((U32)p[0]<<24) + ((U32)p[1]<<16) + ((U32)p[2]<<8) + ((U32)p[3]<<0));
1394 }
1395
1396
1397 /**************************************
1398 * Local structures
1399 ***************************************/
1400 typedef struct ZSTD_Cctx_s ZSTD_Cctx;
1401
1402 typedef enum { bt_compressed, bt_raw, bt_rle, bt_end } blockType_t;
1403
1404 typedef struct
1405 {
1406 blockType_t blockType;
1407 U32 origSize;
1408 } blockProperties_t;
1409
1410 typedef struct {
1411 void* buffer;
1412 U32* offsetStart;
1413 U32* offset;
1414 BYTE* offCodeStart;
1415 BYTE* offCode;
1416 BYTE* litStart;
1417 BYTE* lit;
1418 BYTE* litLengthStart;
1419 BYTE* litLength;
1420 BYTE* matchLengthStart;
1421 BYTE* matchLength;
1422 BYTE* dumpsStart;
1423 BYTE* dumps;
1424 } seqStore_t;
1425
1426
1427 typedef struct ZSTD_Cctx_s
1428 {
1429 const BYTE* base;
1430 U32 current;
1431 U32 nextUpdate;
1432 seqStore_t seqStore;
1433 #ifdef __AVX2__
1434 __m256i hashTable[HASH_TABLESIZE>>3];
1435 #else
1436 U32 hashTable[HASH_TABLESIZE];
1437 #endif
1438 BYTE buffer[WORKPLACESIZE];
1439 } cctxi_t;
1440
1441
1442
1443
1444 /**************************************
1445 * Error Management
1446 **************************************/
1447 /* published entry point */
ZSTDv01_isError(size_t code)1448 unsigned ZSTDv01_isError(size_t code) { return ERR_isError(code); }
1449
1450
1451 /**************************************
1452 * Tool functions
1453 **************************************/
1454 #define ZSTD_VERSION_MAJOR 0 /* for breaking interface changes */
1455 #define ZSTD_VERSION_MINOR 1 /* for new (non-breaking) interface capabilities */
1456 #define ZSTD_VERSION_RELEASE 3 /* for tweaks, bug-fixes, or development */
1457 #define ZSTD_VERSION_NUMBER (ZSTD_VERSION_MAJOR *100*100 + ZSTD_VERSION_MINOR *100 + ZSTD_VERSION_RELEASE)
1458
1459 /**************************************************************
1460 * Decompression code
1461 **************************************************************/
1462
ZSTDv01_getcBlockSize(const void * src,size_t srcSize,blockProperties_t * bpPtr)1463 static size_t ZSTDv01_getcBlockSize(const void* src, size_t srcSize, blockProperties_t* bpPtr)
1464 {
1465 const BYTE* const in = (const BYTE* const)src;
1466 BYTE headerFlags;
1467 U32 cSize;
1468
1469 if (srcSize < 3) return ERROR(srcSize_wrong);
1470
1471 headerFlags = *in;
1472 cSize = in[2] + (in[1]<<8) + ((in[0] & 7)<<16);
1473
1474 bpPtr->blockType = (blockType_t)(headerFlags >> 6);
1475 bpPtr->origSize = (bpPtr->blockType == bt_rle) ? cSize : 0;
1476
1477 if (bpPtr->blockType == bt_end) return 0;
1478 if (bpPtr->blockType == bt_rle) return 1;
1479 return cSize;
1480 }
1481
1482
ZSTD_copyUncompressedBlock(void * dst,size_t maxDstSize,const void * src,size_t srcSize)1483 static size_t ZSTD_copyUncompressedBlock(void* dst, size_t maxDstSize, const void* src, size_t srcSize)
1484 {
1485 if (srcSize > maxDstSize) return ERROR(dstSize_tooSmall);
1486 if (srcSize > 0) {
1487 memcpy(dst, src, srcSize);
1488 }
1489 return srcSize;
1490 }
1491
1492
ZSTD_decompressLiterals(void * ctx,void * dst,size_t maxDstSize,const void * src,size_t srcSize)1493 static size_t ZSTD_decompressLiterals(void* ctx,
1494 void* dst, size_t maxDstSize,
1495 const void* src, size_t srcSize)
1496 {
1497 BYTE* op = (BYTE*)dst;
1498 BYTE* const oend = op + maxDstSize;
1499 const BYTE* ip = (const BYTE*)src;
1500 size_t errorCode;
1501 size_t litSize;
1502
1503 /* check : minimum 2, for litSize, +1, for content */
1504 if (srcSize <= 3) return ERROR(corruption_detected);
1505
1506 litSize = ip[1] + (ip[0]<<8);
1507 litSize += ((ip[-3] >> 3) & 7) << 16; /* mmmmh.... */
1508 op = oend - litSize;
1509
1510 (void)ctx;
1511 if (litSize > maxDstSize) return ERROR(dstSize_tooSmall);
1512 errorCode = HUF_decompress(op, litSize, ip+2, srcSize-2);
1513 if (FSE_isError(errorCode)) return ERROR(GENERIC);
1514 return litSize;
1515 }
1516
1517
ZSTDv01_decodeLiteralsBlock(void * ctx,void * dst,size_t maxDstSize,const BYTE ** litStart,size_t * litSize,const void * src,size_t srcSize)1518 static size_t ZSTDv01_decodeLiteralsBlock(void* ctx,
1519 void* dst, size_t maxDstSize,
1520 const BYTE** litStart, size_t* litSize,
1521 const void* src, size_t srcSize)
1522 {
1523 const BYTE* const istart = (const BYTE* const)src;
1524 const BYTE* ip = istart;
1525 BYTE* const ostart = (BYTE* const)dst;
1526 BYTE* const oend = ostart + maxDstSize;
1527 blockProperties_t litbp;
1528
1529 size_t litcSize = ZSTDv01_getcBlockSize(src, srcSize, &litbp);
1530 if (ZSTDv01_isError(litcSize)) return litcSize;
1531 if (litcSize > srcSize - ZSTD_blockHeaderSize) return ERROR(srcSize_wrong);
1532 ip += ZSTD_blockHeaderSize;
1533
1534 switch(litbp.blockType)
1535 {
1536 case bt_raw:
1537 *litStart = ip;
1538 ip += litcSize;
1539 *litSize = litcSize;
1540 break;
1541 case bt_rle:
1542 {
1543 size_t rleSize = litbp.origSize;
1544 if (rleSize>maxDstSize) return ERROR(dstSize_tooSmall);
1545 if (!srcSize) return ERROR(srcSize_wrong);
1546 if (rleSize > 0) {
1547 memset(oend - rleSize, *ip, rleSize);
1548 }
1549 *litStart = oend - rleSize;
1550 *litSize = rleSize;
1551 ip++;
1552 break;
1553 }
1554 case bt_compressed:
1555 {
1556 size_t decodedLitSize = ZSTD_decompressLiterals(ctx, dst, maxDstSize, ip, litcSize);
1557 if (ZSTDv01_isError(decodedLitSize)) return decodedLitSize;
1558 *litStart = oend - decodedLitSize;
1559 *litSize = decodedLitSize;
1560 ip += litcSize;
1561 break;
1562 }
1563 case bt_end:
1564 default:
1565 return ERROR(GENERIC);
1566 }
1567
1568 return ip-istart;
1569 }
1570
1571
ZSTDv01_decodeSeqHeaders(int * nbSeq,const BYTE ** dumpsPtr,size_t * dumpsLengthPtr,FSE_DTable * DTableLL,FSE_DTable * DTableML,FSE_DTable * DTableOffb,const void * src,size_t srcSize)1572 static size_t ZSTDv01_decodeSeqHeaders(int* nbSeq, const BYTE** dumpsPtr, size_t* dumpsLengthPtr,
1573 FSE_DTable* DTableLL, FSE_DTable* DTableML, FSE_DTable* DTableOffb,
1574 const void* src, size_t srcSize)
1575 {
1576 const BYTE* const istart = (const BYTE* const)src;
1577 const BYTE* ip = istart;
1578 const BYTE* const iend = istart + srcSize;
1579 U32 LLtype, Offtype, MLtype;
1580 U32 LLlog, Offlog, MLlog;
1581 size_t dumpsLength;
1582
1583 /* check */
1584 if (srcSize < 5) return ERROR(srcSize_wrong);
1585
1586 /* SeqHead */
1587 *nbSeq = ZSTD_readLE16(ip); ip+=2;
1588 LLtype = *ip >> 6;
1589 Offtype = (*ip >> 4) & 3;
1590 MLtype = (*ip >> 2) & 3;
1591 if (*ip & 2)
1592 {
1593 dumpsLength = ip[2];
1594 dumpsLength += ip[1] << 8;
1595 ip += 3;
1596 }
1597 else
1598 {
1599 dumpsLength = ip[1];
1600 dumpsLength += (ip[0] & 1) << 8;
1601 ip += 2;
1602 }
1603 *dumpsPtr = ip;
1604 ip += dumpsLength;
1605 *dumpsLengthPtr = dumpsLength;
1606
1607 /* check */
1608 if (ip > iend-3) return ERROR(srcSize_wrong); /* min : all 3 are "raw", hence no header, but at least xxLog bits per type */
1609
1610 /* sequences */
1611 {
1612 S16 norm[MaxML+1]; /* assumption : MaxML >= MaxLL and MaxOff */
1613 size_t headerSize;
1614
1615 /* Build DTables */
1616 switch(LLtype)
1617 {
1618 case bt_rle :
1619 LLlog = 0;
1620 FSE_buildDTable_rle(DTableLL, *ip++); break;
1621 case bt_raw :
1622 LLlog = LLbits;
1623 FSE_buildDTable_raw(DTableLL, LLbits); break;
1624 default :
1625 { U32 max = MaxLL;
1626 headerSize = FSE_readNCount(norm, &max, &LLlog, ip, iend-ip);
1627 if (FSE_isError(headerSize)) return ERROR(GENERIC);
1628 if (LLlog > LLFSELog) return ERROR(corruption_detected);
1629 ip += headerSize;
1630 FSE_buildDTable(DTableLL, norm, max, LLlog);
1631 } }
1632
1633 switch(Offtype)
1634 {
1635 case bt_rle :
1636 Offlog = 0;
1637 if (ip > iend-2) return ERROR(srcSize_wrong); /* min : "raw", hence no header, but at least xxLog bits */
1638 FSE_buildDTable_rle(DTableOffb, *ip++); break;
1639 case bt_raw :
1640 Offlog = Offbits;
1641 FSE_buildDTable_raw(DTableOffb, Offbits); break;
1642 default :
1643 { U32 max = MaxOff;
1644 headerSize = FSE_readNCount(norm, &max, &Offlog, ip, iend-ip);
1645 if (FSE_isError(headerSize)) return ERROR(GENERIC);
1646 if (Offlog > OffFSELog) return ERROR(corruption_detected);
1647 ip += headerSize;
1648 FSE_buildDTable(DTableOffb, norm, max, Offlog);
1649 } }
1650
1651 switch(MLtype)
1652 {
1653 case bt_rle :
1654 MLlog = 0;
1655 if (ip > iend-2) return ERROR(srcSize_wrong); /* min : "raw", hence no header, but at least xxLog bits */
1656 FSE_buildDTable_rle(DTableML, *ip++); break;
1657 case bt_raw :
1658 MLlog = MLbits;
1659 FSE_buildDTable_raw(DTableML, MLbits); break;
1660 default :
1661 { U32 max = MaxML;
1662 headerSize = FSE_readNCount(norm, &max, &MLlog, ip, iend-ip);
1663 if (FSE_isError(headerSize)) return ERROR(GENERIC);
1664 if (MLlog > MLFSELog) return ERROR(corruption_detected);
1665 ip += headerSize;
1666 FSE_buildDTable(DTableML, norm, max, MLlog);
1667 } } }
1668
1669 return ip-istart;
1670 }
1671
1672
1673 typedef struct {
1674 size_t litLength;
1675 size_t offset;
1676 size_t matchLength;
1677 } seq_t;
1678
1679 typedef struct {
1680 FSE_DStream_t DStream;
1681 FSE_DState_t stateLL;
1682 FSE_DState_t stateOffb;
1683 FSE_DState_t stateML;
1684 size_t prevOffset;
1685 const BYTE* dumps;
1686 const BYTE* dumpsEnd;
1687 } seqState_t;
1688
1689
ZSTD_decodeSequence(seq_t * seq,seqState_t * seqState)1690 static void ZSTD_decodeSequence(seq_t* seq, seqState_t* seqState)
1691 {
1692 size_t litLength;
1693 size_t prevOffset;
1694 size_t offset;
1695 size_t matchLength;
1696 const BYTE* dumps = seqState->dumps;
1697 const BYTE* const de = seqState->dumpsEnd;
1698
1699 /* Literal length */
1700 litLength = FSE_decodeSymbol(&(seqState->stateLL), &(seqState->DStream));
1701 prevOffset = litLength ? seq->offset : seqState->prevOffset;
1702 seqState->prevOffset = seq->offset;
1703 if (litLength == MaxLL)
1704 {
1705 const U32 add = dumps<de ? *dumps++ : 0;
1706 if (add < 255) litLength += add;
1707 else
1708 {
1709 if (dumps<=(de-3))
1710 {
1711 litLength = ZSTD_readLE24(dumps);
1712 dumps += 3;
1713 }
1714 }
1715 }
1716
1717 /* Offset */
1718 {
1719 U32 offsetCode, nbBits;
1720 offsetCode = FSE_decodeSymbol(&(seqState->stateOffb), &(seqState->DStream));
1721 if (ZSTD_32bits()) FSE_reloadDStream(&(seqState->DStream));
1722 nbBits = offsetCode - 1;
1723 if (offsetCode==0) nbBits = 0; /* cmove */
1724 offset = ((size_t)1 << (nbBits & ((sizeof(offset)*8)-1))) + FSE_readBits(&(seqState->DStream), nbBits);
1725 if (ZSTD_32bits()) FSE_reloadDStream(&(seqState->DStream));
1726 if (offsetCode==0) offset = prevOffset;
1727 }
1728
1729 /* MatchLength */
1730 matchLength = FSE_decodeSymbol(&(seqState->stateML), &(seqState->DStream));
1731 if (matchLength == MaxML)
1732 {
1733 const U32 add = dumps<de ? *dumps++ : 0;
1734 if (add < 255) matchLength += add;
1735 else
1736 {
1737 if (dumps<=(de-3))
1738 {
1739 matchLength = ZSTD_readLE24(dumps);
1740 dumps += 3;
1741 }
1742 }
1743 }
1744 matchLength += MINMATCH;
1745
1746 /* save result */
1747 seq->litLength = litLength;
1748 seq->offset = offset;
1749 seq->matchLength = matchLength;
1750 seqState->dumps = dumps;
1751 }
1752
1753
ZSTD_execSequence(BYTE * op,seq_t sequence,const BYTE ** litPtr,const BYTE * const litLimit,BYTE * const base,BYTE * const oend)1754 static size_t ZSTD_execSequence(BYTE* op,
1755 seq_t sequence,
1756 const BYTE** litPtr, const BYTE* const litLimit,
1757 BYTE* const base, BYTE* const oend)
1758 {
1759 static const int dec32table[] = {0, 1, 2, 1, 4, 4, 4, 4}; /* added */
1760 static const int dec64table[] = {8, 8, 8, 7, 8, 9,10,11}; /* subtracted */
1761 const BYTE* const ostart = op;
1762 const size_t litLength = sequence.litLength;
1763 BYTE* const endMatch = op + litLength + sequence.matchLength; /* risk : address space overflow (32-bits) */
1764 const BYTE* const litEnd = *litPtr + litLength;
1765
1766 /* check */
1767 if (endMatch > oend) return ERROR(dstSize_tooSmall); /* overwrite beyond dst buffer */
1768 if (litEnd > litLimit) return ERROR(corruption_detected);
1769 if (sequence.matchLength > (size_t)(*litPtr-op)) return ERROR(dstSize_tooSmall); /* overwrite literal segment */
1770
1771 /* copy Literals */
1772 if (((size_t)(*litPtr - op) < 8) || ((size_t)(oend-litEnd) < 8) || (op+litLength > oend-8))
1773 memmove(op, *litPtr, litLength); /* overwrite risk */
1774 else
1775 ZSTD_wildcopy(op, *litPtr, litLength);
1776 op += litLength;
1777 *litPtr = litEnd; /* update for next sequence */
1778
1779 /* check : last match must be at a minimum distance of 8 from end of dest buffer */
1780 if (oend-op < 8) return ERROR(dstSize_tooSmall);
1781
1782 /* copy Match */
1783 {
1784 const U32 overlapRisk = (((size_t)(litEnd - endMatch)) < 12);
1785 const BYTE* match = op - sequence.offset; /* possible underflow at op - offset ? */
1786 size_t qutt = 12;
1787 U64 saved[2];
1788
1789 /* check */
1790 if (match < base) return ERROR(corruption_detected);
1791 if (sequence.offset > (size_t)base) return ERROR(corruption_detected);
1792
1793 /* save beginning of literal sequence, in case of write overlap */
1794 if (overlapRisk)
1795 {
1796 if ((endMatch + qutt) > oend) qutt = oend-endMatch;
1797 memcpy(saved, endMatch, qutt);
1798 }
1799
1800 if (sequence.offset < 8)
1801 {
1802 const int dec64 = dec64table[sequence.offset];
1803 op[0] = match[0];
1804 op[1] = match[1];
1805 op[2] = match[2];
1806 op[3] = match[3];
1807 match += dec32table[sequence.offset];
1808 ZSTD_copy4(op+4, match);
1809 match -= dec64;
1810 } else { ZSTD_copy8(op, match); }
1811 op += 8; match += 8;
1812
1813 if (endMatch > oend-(16-MINMATCH))
1814 {
1815 if (op < oend-8)
1816 {
1817 ZSTD_wildcopy(op, match, (oend-8) - op);
1818 match += (oend-8) - op;
1819 op = oend-8;
1820 }
1821 while (op<endMatch) *op++ = *match++;
1822 }
1823 else
1824 ZSTD_wildcopy(op, match, (ptrdiff_t)sequence.matchLength-8); /* works even if matchLength < 8 */
1825
1826 /* restore, in case of overlap */
1827 if (overlapRisk) memcpy(endMatch, saved, qutt);
1828 }
1829
1830 return endMatch-ostart;
1831 }
1832
1833 typedef struct ZSTDv01_Dctx_s
1834 {
1835 U32 LLTable[FSE_DTABLE_SIZE_U32(LLFSELog)];
1836 U32 OffTable[FSE_DTABLE_SIZE_U32(OffFSELog)];
1837 U32 MLTable[FSE_DTABLE_SIZE_U32(MLFSELog)];
1838 void* previousDstEnd;
1839 void* base;
1840 size_t expected;
1841 blockType_t bType;
1842 U32 phase;
1843 } dctx_t;
1844
1845
ZSTD_decompressSequences(void * ctx,void * dst,size_t maxDstSize,const void * seqStart,size_t seqSize,const BYTE * litStart,size_t litSize)1846 static size_t ZSTD_decompressSequences(
1847 void* ctx,
1848 void* dst, size_t maxDstSize,
1849 const void* seqStart, size_t seqSize,
1850 const BYTE* litStart, size_t litSize)
1851 {
1852 dctx_t* dctx = (dctx_t*)ctx;
1853 const BYTE* ip = (const BYTE*)seqStart;
1854 const BYTE* const iend = ip + seqSize;
1855 BYTE* const ostart = (BYTE* const)dst;
1856 BYTE* op = ostart;
1857 BYTE* const oend = ostart + maxDstSize;
1858 size_t errorCode, dumpsLength;
1859 const BYTE* litPtr = litStart;
1860 const BYTE* const litEnd = litStart + litSize;
1861 int nbSeq;
1862 const BYTE* dumps;
1863 U32* DTableLL = dctx->LLTable;
1864 U32* DTableML = dctx->MLTable;
1865 U32* DTableOffb = dctx->OffTable;
1866 BYTE* const base = (BYTE*) (dctx->base);
1867
1868 /* Build Decoding Tables */
1869 errorCode = ZSTDv01_decodeSeqHeaders(&nbSeq, &dumps, &dumpsLength,
1870 DTableLL, DTableML, DTableOffb,
1871 ip, iend-ip);
1872 if (ZSTDv01_isError(errorCode)) return errorCode;
1873 ip += errorCode;
1874
1875 /* Regen sequences */
1876 {
1877 seq_t sequence;
1878 seqState_t seqState;
1879
1880 memset(&sequence, 0, sizeof(sequence));
1881 seqState.dumps = dumps;
1882 seqState.dumpsEnd = dumps + dumpsLength;
1883 seqState.prevOffset = 1;
1884 errorCode = FSE_initDStream(&(seqState.DStream), ip, iend-ip);
1885 if (FSE_isError(errorCode)) return ERROR(corruption_detected);
1886 FSE_initDState(&(seqState.stateLL), &(seqState.DStream), DTableLL);
1887 FSE_initDState(&(seqState.stateOffb), &(seqState.DStream), DTableOffb);
1888 FSE_initDState(&(seqState.stateML), &(seqState.DStream), DTableML);
1889
1890 for ( ; (FSE_reloadDStream(&(seqState.DStream)) <= FSE_DStream_completed) && (nbSeq>0) ; )
1891 {
1892 size_t oneSeqSize;
1893 nbSeq--;
1894 ZSTD_decodeSequence(&sequence, &seqState);
1895 oneSeqSize = ZSTD_execSequence(op, sequence, &litPtr, litEnd, base, oend);
1896 if (ZSTDv01_isError(oneSeqSize)) return oneSeqSize;
1897 op += oneSeqSize;
1898 }
1899
1900 /* check if reached exact end */
1901 if ( !FSE_endOfDStream(&(seqState.DStream)) ) return ERROR(corruption_detected); /* requested too much : data is corrupted */
1902 if (nbSeq<0) return ERROR(corruption_detected); /* requested too many sequences : data is corrupted */
1903
1904 /* last literal segment */
1905 {
1906 size_t lastLLSize = litEnd - litPtr;
1907 if (op+lastLLSize > oend) return ERROR(dstSize_tooSmall);
1908 if (lastLLSize > 0) {
1909 if (op != litPtr) memmove(op, litPtr, lastLLSize);
1910 op += lastLLSize;
1911 }
1912 }
1913 }
1914
1915 return op-ostart;
1916 }
1917
1918
ZSTD_decompressBlock(void * ctx,void * dst,size_t maxDstSize,const void * src,size_t srcSize)1919 static size_t ZSTD_decompressBlock(
1920 void* ctx,
1921 void* dst, size_t maxDstSize,
1922 const void* src, size_t srcSize)
1923 {
1924 /* blockType == blockCompressed, srcSize is trusted */
1925 const BYTE* ip = (const BYTE*)src;
1926 const BYTE* litPtr = NULL;
1927 size_t litSize = 0;
1928 size_t errorCode;
1929
1930 /* Decode literals sub-block */
1931 errorCode = ZSTDv01_decodeLiteralsBlock(ctx, dst, maxDstSize, &litPtr, &litSize, src, srcSize);
1932 if (ZSTDv01_isError(errorCode)) return errorCode;
1933 ip += errorCode;
1934 srcSize -= errorCode;
1935
1936 return ZSTD_decompressSequences(ctx, dst, maxDstSize, ip, srcSize, litPtr, litSize);
1937 }
1938
1939
ZSTDv01_decompressDCtx(void * ctx,void * dst,size_t maxDstSize,const void * src,size_t srcSize)1940 size_t ZSTDv01_decompressDCtx(void* ctx, void* dst, size_t maxDstSize, const void* src, size_t srcSize)
1941 {
1942 const BYTE* ip = (const BYTE*)src;
1943 const BYTE* iend = ip + srcSize;
1944 BYTE* const ostart = (BYTE* const)dst;
1945 BYTE* op = ostart;
1946 BYTE* const oend = ostart + maxDstSize;
1947 size_t remainingSize = srcSize;
1948 U32 magicNumber;
1949 size_t errorCode=0;
1950 blockProperties_t blockProperties;
1951
1952 /* Frame Header */
1953 if (srcSize < ZSTD_frameHeaderSize+ZSTD_blockHeaderSize) return ERROR(srcSize_wrong);
1954 magicNumber = ZSTD_readBE32(src);
1955 if (magicNumber != ZSTD_magicNumber) return ERROR(prefix_unknown);
1956 ip += ZSTD_frameHeaderSize; remainingSize -= ZSTD_frameHeaderSize;
1957
1958 /* Loop on each block */
1959 while (1)
1960 {
1961 size_t blockSize = ZSTDv01_getcBlockSize(ip, iend-ip, &blockProperties);
1962 if (ZSTDv01_isError(blockSize)) return blockSize;
1963
1964 ip += ZSTD_blockHeaderSize;
1965 remainingSize -= ZSTD_blockHeaderSize;
1966 if (blockSize > remainingSize) return ERROR(srcSize_wrong);
1967
1968 switch(blockProperties.blockType)
1969 {
1970 case bt_compressed:
1971 errorCode = ZSTD_decompressBlock(ctx, op, oend-op, ip, blockSize);
1972 break;
1973 case bt_raw :
1974 errorCode = ZSTD_copyUncompressedBlock(op, oend-op, ip, blockSize);
1975 break;
1976 case bt_rle :
1977 return ERROR(GENERIC); /* not yet supported */
1978 break;
1979 case bt_end :
1980 /* end of frame */
1981 if (remainingSize) return ERROR(srcSize_wrong);
1982 break;
1983 default:
1984 return ERROR(GENERIC);
1985 }
1986 if (blockSize == 0) break; /* bt_end */
1987
1988 if (ZSTDv01_isError(errorCode)) return errorCode;
1989 op += errorCode;
1990 ip += blockSize;
1991 remainingSize -= blockSize;
1992 }
1993
1994 return op-ostart;
1995 }
1996
ZSTDv01_decompress(void * dst,size_t maxDstSize,const void * src,size_t srcSize)1997 size_t ZSTDv01_decompress(void* dst, size_t maxDstSize, const void* src, size_t srcSize)
1998 {
1999 dctx_t ctx;
2000 ctx.base = dst;
2001 return ZSTDv01_decompressDCtx(&ctx, dst, maxDstSize, src, srcSize);
2002 }
2003
2004 /* ZSTD_errorFrameSizeInfoLegacy() :
2005 assumes `cSize` and `dBound` are _not_ NULL */
ZSTD_errorFrameSizeInfoLegacy(size_t * cSize,unsigned long long * dBound,size_t ret)2006 static void ZSTD_errorFrameSizeInfoLegacy(size_t* cSize, unsigned long long* dBound, size_t ret)
2007 {
2008 *cSize = ret;
2009 *dBound = ZSTD_CONTENTSIZE_ERROR;
2010 }
2011
ZSTDv01_findFrameSizeInfoLegacy(const void * src,size_t srcSize,size_t * cSize,unsigned long long * dBound)2012 void ZSTDv01_findFrameSizeInfoLegacy(const void *src, size_t srcSize, size_t* cSize, unsigned long long* dBound)
2013 {
2014 const BYTE* ip = (const BYTE*)src;
2015 size_t remainingSize = srcSize;
2016 size_t nbBlocks = 0;
2017 U32 magicNumber;
2018 blockProperties_t blockProperties;
2019
2020 /* Frame Header */
2021 if (srcSize < ZSTD_frameHeaderSize+ZSTD_blockHeaderSize) {
2022 ZSTD_errorFrameSizeInfoLegacy(cSize, dBound, ERROR(srcSize_wrong));
2023 return;
2024 }
2025 magicNumber = ZSTD_readBE32(src);
2026 if (magicNumber != ZSTD_magicNumber) {
2027 ZSTD_errorFrameSizeInfoLegacy(cSize, dBound, ERROR(prefix_unknown));
2028 return;
2029 }
2030 ip += ZSTD_frameHeaderSize; remainingSize -= ZSTD_frameHeaderSize;
2031
2032 /* Loop on each block */
2033 while (1)
2034 {
2035 size_t blockSize = ZSTDv01_getcBlockSize(ip, remainingSize, &blockProperties);
2036 if (ZSTDv01_isError(blockSize)) {
2037 ZSTD_errorFrameSizeInfoLegacy(cSize, dBound, blockSize);
2038 return;
2039 }
2040
2041 ip += ZSTD_blockHeaderSize;
2042 remainingSize -= ZSTD_blockHeaderSize;
2043 if (blockSize > remainingSize) {
2044 ZSTD_errorFrameSizeInfoLegacy(cSize, dBound, ERROR(srcSize_wrong));
2045 return;
2046 }
2047
2048 if (blockSize == 0) break; /* bt_end */
2049
2050 ip += blockSize;
2051 remainingSize -= blockSize;
2052 nbBlocks++;
2053 }
2054
2055 *cSize = ip - (const BYTE*)src;
2056 *dBound = nbBlocks * BLOCKSIZE;
2057 }
2058
2059 /*******************************
2060 * Streaming Decompression API
2061 *******************************/
2062
ZSTDv01_resetDCtx(ZSTDv01_Dctx * dctx)2063 size_t ZSTDv01_resetDCtx(ZSTDv01_Dctx* dctx)
2064 {
2065 dctx->expected = ZSTD_frameHeaderSize;
2066 dctx->phase = 0;
2067 dctx->previousDstEnd = NULL;
2068 dctx->base = NULL;
2069 return 0;
2070 }
2071
ZSTDv01_createDCtx(void)2072 ZSTDv01_Dctx* ZSTDv01_createDCtx(void)
2073 {
2074 ZSTDv01_Dctx* dctx = (ZSTDv01_Dctx*)malloc(sizeof(ZSTDv01_Dctx));
2075 if (dctx==NULL) return NULL;
2076 ZSTDv01_resetDCtx(dctx);
2077 return dctx;
2078 }
2079
ZSTDv01_freeDCtx(ZSTDv01_Dctx * dctx)2080 size_t ZSTDv01_freeDCtx(ZSTDv01_Dctx* dctx)
2081 {
2082 free(dctx);
2083 return 0;
2084 }
2085
ZSTDv01_nextSrcSizeToDecompress(ZSTDv01_Dctx * dctx)2086 size_t ZSTDv01_nextSrcSizeToDecompress(ZSTDv01_Dctx* dctx)
2087 {
2088 return ((dctx_t*)dctx)->expected;
2089 }
2090
ZSTDv01_decompressContinue(ZSTDv01_Dctx * dctx,void * dst,size_t maxDstSize,const void * src,size_t srcSize)2091 size_t ZSTDv01_decompressContinue(ZSTDv01_Dctx* dctx, void* dst, size_t maxDstSize, const void* src, size_t srcSize)
2092 {
2093 dctx_t* ctx = (dctx_t*)dctx;
2094
2095 /* Sanity check */
2096 if (srcSize != ctx->expected) return ERROR(srcSize_wrong);
2097 if (dst != ctx->previousDstEnd) /* not contiguous */
2098 ctx->base = dst;
2099
2100 /* Decompress : frame header */
2101 if (ctx->phase == 0)
2102 {
2103 /* Check frame magic header */
2104 U32 magicNumber = ZSTD_readBE32(src);
2105 if (magicNumber != ZSTD_magicNumber) return ERROR(prefix_unknown);
2106 ctx->phase = 1;
2107 ctx->expected = ZSTD_blockHeaderSize;
2108 return 0;
2109 }
2110
2111 /* Decompress : block header */
2112 if (ctx->phase == 1)
2113 {
2114 blockProperties_t bp;
2115 size_t blockSize = ZSTDv01_getcBlockSize(src, ZSTD_blockHeaderSize, &bp);
2116 if (ZSTDv01_isError(blockSize)) return blockSize;
2117 if (bp.blockType == bt_end)
2118 {
2119 ctx->expected = 0;
2120 ctx->phase = 0;
2121 }
2122 else
2123 {
2124 ctx->expected = blockSize;
2125 ctx->bType = bp.blockType;
2126 ctx->phase = 2;
2127 }
2128
2129 return 0;
2130 }
2131
2132 /* Decompress : block content */
2133 {
2134 size_t rSize;
2135 switch(ctx->bType)
2136 {
2137 case bt_compressed:
2138 rSize = ZSTD_decompressBlock(ctx, dst, maxDstSize, src, srcSize);
2139 break;
2140 case bt_raw :
2141 rSize = ZSTD_copyUncompressedBlock(dst, maxDstSize, src, srcSize);
2142 break;
2143 case bt_rle :
2144 return ERROR(GENERIC); /* not yet handled */
2145 break;
2146 case bt_end : /* should never happen (filtered at phase 1) */
2147 rSize = 0;
2148 break;
2149 default:
2150 return ERROR(GENERIC);
2151 }
2152 ctx->phase = 1;
2153 ctx->expected = ZSTD_blockHeaderSize;
2154 ctx->previousDstEnd = (void*)( ((char*)dst) + rSize);
2155 return rSize;
2156 }
2157
2158 }
2159