648db22b |
1 | /* |
2 | * Copyright (c) Yann Collet, Meta Platforms, Inc. and affiliates. |
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" |
f535537f |
17 | #include "../common/compiler.h" |
648db22b |
18 | #include "../common/error_private.h" |
19 | |
20 | |
21 | /****************************************** |
22 | * Static allocation |
23 | ******************************************/ |
24 | /* You can statically allocate FSE CTable/DTable as a table of unsigned using below macro */ |
25 | #define FSE_DTABLE_SIZE_U32(maxTableLog) (1 + (1<<maxTableLog)) |
26 | |
27 | /* You can statically allocate Huff0 DTable as a table of unsigned short using below macro */ |
28 | #define HUF_DTABLE_SIZE_U16(maxTableLog) (1 + (1<<maxTableLog)) |
29 | #define HUF_CREATE_STATIC_DTABLE(DTable, maxTableLog) \ |
30 | unsigned short DTable[HUF_DTABLE_SIZE_U16(maxTableLog)] = { maxTableLog } |
31 | |
32 | |
33 | /****************************************** |
34 | * Error Management |
35 | ******************************************/ |
36 | #define FSE_LIST_ERRORS(ITEM) \ |
37 | ITEM(FSE_OK_NoError) ITEM(FSE_ERROR_GENERIC) \ |
38 | ITEM(FSE_ERROR_tableLog_tooLarge) ITEM(FSE_ERROR_maxSymbolValue_tooLarge) ITEM(FSE_ERROR_maxSymbolValue_tooSmall) \ |
39 | ITEM(FSE_ERROR_dstSize_tooSmall) ITEM(FSE_ERROR_srcSize_wrong)\ |
40 | ITEM(FSE_ERROR_corruptionDetected) \ |
41 | ITEM(FSE_ERROR_maxCode) |
42 | |
43 | #define FSE_GENERATE_ENUM(ENUM) ENUM, |
44 | typedef enum { FSE_LIST_ERRORS(FSE_GENERATE_ENUM) } FSE_errorCodes; /* enum is exposed, to detect & handle specific errors; compare function result to -enum value */ |
45 | |
46 | |
47 | /****************************************** |
48 | * FSE symbol compression API |
49 | ******************************************/ |
50 | /* |
51 | This API consists of small unitary functions, which highly benefit from being inlined. |
52 | You will want to enable link-time-optimization to ensure these functions are properly inlined in your binary. |
53 | Visual seems to do it automatically. |
54 | For gcc or clang, you'll need to add -flto flag at compilation and linking stages. |
55 | If none of these solutions is applicable, include "fse.c" directly. |
56 | */ |
57 | |
58 | typedef unsigned FSE_CTable; /* don't allocate that. It's just a way to be more restrictive than void* */ |
59 | typedef unsigned FSE_DTable; /* don't allocate that. It's just a way to be more restrictive than void* */ |
60 | |
61 | typedef struct |
62 | { |
63 | size_t bitContainer; |
64 | int bitPos; |
65 | char* startPtr; |
66 | char* ptr; |
67 | char* endPtr; |
68 | } FSE_CStream_t; |
69 | |
70 | typedef struct |
71 | { |
72 | ptrdiff_t value; |
73 | const void* stateTable; |
74 | const void* symbolTT; |
75 | unsigned stateLog; |
76 | } FSE_CState_t; |
77 | |
78 | typedef struct |
79 | { |
80 | size_t bitContainer; |
81 | unsigned bitsConsumed; |
82 | const char* ptr; |
83 | const char* start; |
84 | } FSE_DStream_t; |
85 | |
86 | typedef struct |
87 | { |
88 | size_t state; |
89 | const void* table; /* precise table may vary, depending on U16 */ |
90 | } FSE_DState_t; |
91 | |
92 | typedef enum { FSE_DStream_unfinished = 0, |
93 | FSE_DStream_endOfBuffer = 1, |
94 | FSE_DStream_completed = 2, |
95 | FSE_DStream_tooFar = 3 } FSE_DStream_status; /* result of FSE_reloadDStream() */ |
96 | /* 1,2,4,8 would be better for bitmap combinations, but slows down performance a bit ... ?! */ |
97 | |
98 | |
99 | /**************************************************************** |
100 | * Tuning parameters |
101 | ****************************************************************/ |
102 | /* MEMORY_USAGE : |
103 | * Memory usage formula : N->2^N Bytes (examples : 10 -> 1KB; 12 -> 4KB ; 16 -> 64KB; 20 -> 1MB; etc.) |
104 | * Increasing memory usage improves compression ratio |
105 | * Reduced memory usage can improve speed, due to cache effect |
106 | * Recommended max value is 14, for 16KB, which nicely fits into Intel x86 L1 cache */ |
107 | #define FSE_MAX_MEMORY_USAGE 14 |
108 | #define FSE_DEFAULT_MEMORY_USAGE 13 |
109 | |
110 | /* FSE_MAX_SYMBOL_VALUE : |
111 | * Maximum symbol value authorized. |
112 | * Required for proper stack allocation */ |
113 | #define FSE_MAX_SYMBOL_VALUE 255 |
114 | |
115 | |
116 | /**************************************************************** |
117 | * template functions type & suffix |
118 | ****************************************************************/ |
119 | #define FSE_FUNCTION_TYPE BYTE |
120 | #define FSE_FUNCTION_EXTENSION |
121 | |
122 | |
123 | /**************************************************************** |
124 | * Byte symbol type |
125 | ****************************************************************/ |
126 | typedef struct |
127 | { |
128 | unsigned short newState; |
129 | unsigned char symbol; |
130 | unsigned char nbBits; |
131 | } FSE_decode_t; /* size == U32 */ |
132 | |
133 | |
134 | |
135 | /**************************************************************** |
136 | * Compiler specifics |
137 | ****************************************************************/ |
138 | #ifdef _MSC_VER /* Visual Studio */ |
139 | # define FORCE_INLINE static __forceinline |
140 | # include <intrin.h> /* For Visual 2005 */ |
141 | # pragma warning(disable : 4127) /* disable: C4127: conditional expression is constant */ |
142 | # pragma warning(disable : 4214) /* disable: C4214: non-int bitfields */ |
143 | #else |
144 | # define GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__) |
145 | # if defined (__cplusplus) || defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L /* C99 */ |
146 | # ifdef __GNUC__ |
147 | # define FORCE_INLINE static inline __attribute__((always_inline)) |
148 | # else |
149 | # define FORCE_INLINE static inline |
150 | # endif |
151 | # else |
152 | # define FORCE_INLINE static |
153 | # endif /* __STDC_VERSION__ */ |
154 | #endif |
155 | |
156 | |
157 | /**************************************************************** |
158 | * Includes |
159 | ****************************************************************/ |
160 | #include <stdlib.h> /* malloc, free, qsort */ |
161 | #include <string.h> /* memcpy, memset */ |
162 | #include <stdio.h> /* printf (debug) */ |
163 | |
164 | |
165 | #ifndef MEM_ACCESS_MODULE |
166 | #define MEM_ACCESS_MODULE |
167 | /**************************************************************** |
168 | * Basic Types |
169 | *****************************************************************/ |
170 | #if defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L /* C99 */ |
171 | # include <stdint.h> |
172 | typedef uint8_t BYTE; |
173 | typedef uint16_t U16; |
174 | typedef int16_t S16; |
175 | typedef uint32_t U32; |
176 | typedef int32_t S32; |
177 | typedef uint64_t U64; |
178 | typedef int64_t S64; |
179 | #else |
180 | typedef unsigned char BYTE; |
181 | typedef unsigned short U16; |
182 | typedef signed short S16; |
183 | typedef unsigned int U32; |
184 | typedef signed int S32; |
185 | typedef unsigned long long U64; |
186 | typedef signed long long S64; |
187 | #endif |
188 | |
189 | #endif /* MEM_ACCESS_MODULE */ |
190 | |
191 | /**************************************************************** |
192 | * Memory I/O |
193 | *****************************************************************/ |
194 | |
195 | static unsigned FSE_32bits(void) |
196 | { |
197 | return sizeof(void*)==4; |
198 | } |
199 | |
200 | static unsigned FSE_isLittleEndian(void) |
201 | { |
202 | const union { U32 i; BYTE c[4]; } one = { 1 }; /* don't use static : performance detrimental */ |
203 | return one.c[0]; |
204 | } |
205 | |
206 | static U16 FSE_read16(const void* memPtr) |
207 | { |
208 | U16 val; memcpy(&val, memPtr, sizeof(val)); return val; |
209 | } |
210 | |
211 | static U32 FSE_read32(const void* memPtr) |
212 | { |
213 | U32 val; memcpy(&val, memPtr, sizeof(val)); return val; |
214 | } |
215 | |
216 | static U64 FSE_read64(const void* memPtr) |
217 | { |
218 | U64 val; memcpy(&val, memPtr, sizeof(val)); return val; |
219 | } |
220 | |
221 | static U16 FSE_readLE16(const void* memPtr) |
222 | { |
223 | if (FSE_isLittleEndian()) |
224 | return FSE_read16(memPtr); |
225 | else |
226 | { |
227 | const BYTE* p = (const BYTE*)memPtr; |
228 | return (U16)(p[0] + (p[1]<<8)); |
229 | } |
230 | } |
231 | |
232 | static U32 FSE_readLE32(const void* memPtr) |
233 | { |
234 | if (FSE_isLittleEndian()) |
235 | return FSE_read32(memPtr); |
236 | else |
237 | { |
238 | const BYTE* p = (const BYTE*)memPtr; |
239 | return (U32)((U32)p[0] + ((U32)p[1]<<8) + ((U32)p[2]<<16) + ((U32)p[3]<<24)); |
240 | } |
241 | } |
242 | |
243 | |
244 | static U64 FSE_readLE64(const void* memPtr) |
245 | { |
246 | if (FSE_isLittleEndian()) |
247 | return FSE_read64(memPtr); |
248 | else |
249 | { |
250 | const BYTE* p = (const BYTE*)memPtr; |
251 | return (U64)((U64)p[0] + ((U64)p[1]<<8) + ((U64)p[2]<<16) + ((U64)p[3]<<24) |
252 | + ((U64)p[4]<<32) + ((U64)p[5]<<40) + ((U64)p[6]<<48) + ((U64)p[7]<<56)); |
253 | } |
254 | } |
255 | |
256 | static size_t FSE_readLEST(const void* memPtr) |
257 | { |
258 | if (FSE_32bits()) |
259 | return (size_t)FSE_readLE32(memPtr); |
260 | else |
261 | return (size_t)FSE_readLE64(memPtr); |
262 | } |
263 | |
264 | |
265 | |
266 | /**************************************************************** |
267 | * Constants |
268 | *****************************************************************/ |
269 | #define FSE_MAX_TABLELOG (FSE_MAX_MEMORY_USAGE-2) |
270 | #define FSE_MAX_TABLESIZE (1U<<FSE_MAX_TABLELOG) |
271 | #define FSE_MAXTABLESIZE_MASK (FSE_MAX_TABLESIZE-1) |
272 | #define FSE_DEFAULT_TABLELOG (FSE_DEFAULT_MEMORY_USAGE-2) |
273 | #define FSE_MIN_TABLELOG 5 |
274 | |
275 | #define FSE_TABLELOG_ABSOLUTE_MAX 15 |
276 | #if FSE_MAX_TABLELOG > FSE_TABLELOG_ABSOLUTE_MAX |
277 | #error "FSE_MAX_TABLELOG > FSE_TABLELOG_ABSOLUTE_MAX is not supported" |
278 | #endif |
279 | |
280 | |
281 | /**************************************************************** |
282 | * Error Management |
283 | ****************************************************************/ |
284 | #define FSE_STATIC_ASSERT(c) { enum { FSE_static_assert = 1/(int)(!!(c)) }; } /* use only *after* variable declarations */ |
285 | |
286 | |
287 | /**************************************************************** |
288 | * Complex types |
289 | ****************************************************************/ |
290 | typedef struct |
291 | { |
292 | int deltaFindState; |
293 | U32 deltaNbBits; |
294 | } FSE_symbolCompressionTransform; /* total 8 bytes */ |
295 | |
296 | typedef U32 DTable_max_t[FSE_DTABLE_SIZE_U32(FSE_MAX_TABLELOG)]; |
297 | |
298 | /**************************************************************** |
299 | * Internal functions |
300 | ****************************************************************/ |
301 | FORCE_INLINE unsigned FSE_highbit32 (U32 val) |
302 | { |
303 | # if defined(_MSC_VER) /* Visual */ |
304 | unsigned long r; |
305 | return _BitScanReverse(&r, val) ? (unsigned)r : 0; |
306 | # elif defined(__GNUC__) && (GCC_VERSION >= 304) /* GCC Intrinsic */ |
307 | return __builtin_clz (val) ^ 31; |
308 | # else /* Software version */ |
309 | 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 }; |
310 | U32 v = val; |
311 | unsigned r; |
312 | v |= v >> 1; |
313 | v |= v >> 2; |
314 | v |= v >> 4; |
315 | v |= v >> 8; |
316 | v |= v >> 16; |
317 | r = DeBruijnClz[ (U32) (v * 0x07C4ACDDU) >> 27]; |
318 | return r; |
319 | # endif |
320 | } |
321 | |
322 | |
323 | /**************************************************************** |
324 | * Templates |
325 | ****************************************************************/ |
326 | /* |
327 | designed to be included |
328 | for type-specific functions (template emulation in C) |
329 | Objective is to write these functions only once, for improved maintenance |
330 | */ |
331 | |
332 | /* safety checks */ |
333 | #ifndef FSE_FUNCTION_EXTENSION |
334 | # error "FSE_FUNCTION_EXTENSION must be defined" |
335 | #endif |
336 | #ifndef FSE_FUNCTION_TYPE |
337 | # error "FSE_FUNCTION_TYPE must be defined" |
338 | #endif |
339 | |
340 | /* Function names */ |
341 | #define FSE_CAT(X,Y) X##Y |
342 | #define FSE_FUNCTION_NAME(X,Y) FSE_CAT(X,Y) |
343 | #define FSE_TYPE_NAME(X,Y) FSE_CAT(X,Y) |
344 | |
345 | |
346 | |
347 | static U32 FSE_tableStep(U32 tableSize) { return (tableSize>>1) + (tableSize>>3) + 3; } |
348 | |
349 | #define FSE_DECODE_TYPE FSE_decode_t |
350 | |
351 | |
352 | typedef struct { |
353 | U16 tableLog; |
354 | U16 fastMode; |
355 | } FSE_DTableHeader; /* sizeof U32 */ |
356 | |
357 | static size_t FSE_buildDTable |
358 | (FSE_DTable* dt, const short* normalizedCounter, unsigned maxSymbolValue, unsigned tableLog) |
359 | { |
360 | void* ptr = dt; |
361 | FSE_DTableHeader* const DTableH = (FSE_DTableHeader*)ptr; |
362 | FSE_DECODE_TYPE* const tableDecode = (FSE_DECODE_TYPE*)(ptr) + 1; /* because dt is unsigned, 32-bits aligned on 32-bits */ |
363 | const U32 tableSize = 1 << tableLog; |
364 | const U32 tableMask = tableSize-1; |
365 | const U32 step = FSE_tableStep(tableSize); |
366 | U16 symbolNext[FSE_MAX_SYMBOL_VALUE+1]; |
367 | U32 position = 0; |
368 | U32 highThreshold = tableSize-1; |
369 | const S16 largeLimit= (S16)(1 << (tableLog-1)); |
370 | U32 noLarge = 1; |
371 | U32 s; |
372 | |
373 | /* Sanity Checks */ |
374 | if (maxSymbolValue > FSE_MAX_SYMBOL_VALUE) return (size_t)-FSE_ERROR_maxSymbolValue_tooLarge; |
375 | if (tableLog > FSE_MAX_TABLELOG) return (size_t)-FSE_ERROR_tableLog_tooLarge; |
376 | |
377 | /* Init, lay down lowprob symbols */ |
378 | DTableH[0].tableLog = (U16)tableLog; |
379 | for (s=0; s<=maxSymbolValue; s++) |
380 | { |
381 | if (normalizedCounter[s]==-1) |
382 | { |
383 | tableDecode[highThreshold--].symbol = (FSE_FUNCTION_TYPE)s; |
384 | symbolNext[s] = 1; |
385 | } |
386 | else |
387 | { |
388 | if (normalizedCounter[s] >= largeLimit) noLarge=0; |
389 | symbolNext[s] = normalizedCounter[s]; |
390 | } |
391 | } |
392 | |
393 | /* Spread symbols */ |
394 | for (s=0; s<=maxSymbolValue; s++) |
395 | { |
396 | int i; |
397 | for (i=0; i<normalizedCounter[s]; i++) |
398 | { |
399 | tableDecode[position].symbol = (FSE_FUNCTION_TYPE)s; |
400 | position = (position + step) & tableMask; |
401 | while (position > highThreshold) position = (position + step) & tableMask; /* lowprob area */ |
402 | } |
403 | } |
404 | |
405 | if (position!=0) return (size_t)-FSE_ERROR_GENERIC; /* position must reach all cells once, otherwise normalizedCounter is incorrect */ |
406 | |
407 | /* Build Decoding table */ |
408 | { |
409 | U32 i; |
410 | for (i=0; i<tableSize; i++) |
411 | { |
412 | FSE_FUNCTION_TYPE symbol = (FSE_FUNCTION_TYPE)(tableDecode[i].symbol); |
413 | U16 nextState = symbolNext[symbol]++; |
414 | tableDecode[i].nbBits = (BYTE) (tableLog - FSE_highbit32 ((U32)nextState) ); |
415 | tableDecode[i].newState = (U16) ( (nextState << tableDecode[i].nbBits) - tableSize); |
416 | } |
417 | } |
418 | |
419 | DTableH->fastMode = (U16)noLarge; |
420 | return 0; |
421 | } |
422 | |
423 | |
424 | /****************************************** |
425 | * FSE byte symbol |
426 | ******************************************/ |
427 | #ifndef FSE_COMMONDEFS_ONLY |
428 | |
429 | static unsigned FSE_isError(size_t code) { return (code > (size_t)(-FSE_ERROR_maxCode)); } |
430 | |
431 | static short FSE_abs(short a) |
432 | { |
433 | return a<0? -a : a; |
434 | } |
435 | |
436 | |
437 | /**************************************************************** |
438 | * Header bitstream management |
439 | ****************************************************************/ |
440 | static size_t FSE_readNCount (short* normalizedCounter, unsigned* maxSVPtr, unsigned* tableLogPtr, |
441 | const void* headerBuffer, size_t hbSize) |
442 | { |
443 | const BYTE* const istart = (const BYTE*) headerBuffer; |
444 | const BYTE* const iend = istart + hbSize; |
445 | const BYTE* ip = istart; |
446 | int nbBits; |
447 | int remaining; |
448 | int threshold; |
449 | U32 bitStream; |
450 | int bitCount; |
451 | unsigned charnum = 0; |
452 | int previous0 = 0; |
453 | |
454 | if (hbSize < 4) return (size_t)-FSE_ERROR_srcSize_wrong; |
455 | bitStream = FSE_readLE32(ip); |
456 | nbBits = (bitStream & 0xF) + FSE_MIN_TABLELOG; /* extract tableLog */ |
457 | if (nbBits > FSE_TABLELOG_ABSOLUTE_MAX) return (size_t)-FSE_ERROR_tableLog_tooLarge; |
458 | bitStream >>= 4; |
459 | bitCount = 4; |
460 | *tableLogPtr = nbBits; |
461 | remaining = (1<<nbBits)+1; |
462 | threshold = 1<<nbBits; |
463 | nbBits++; |
464 | |
465 | while ((remaining>1) && (charnum<=*maxSVPtr)) |
466 | { |
467 | if (previous0) |
468 | { |
469 | unsigned n0 = charnum; |
470 | while ((bitStream & 0xFFFF) == 0xFFFF) |
471 | { |
472 | n0+=24; |
473 | if (ip < iend-5) |
474 | { |
475 | ip+=2; |
476 | bitStream = FSE_readLE32(ip) >> bitCount; |
477 | } |
478 | else |
479 | { |
480 | bitStream >>= 16; |
481 | bitCount+=16; |
482 | } |
483 | } |
484 | while ((bitStream & 3) == 3) |
485 | { |
486 | n0+=3; |
487 | bitStream>>=2; |
488 | bitCount+=2; |
489 | } |
490 | n0 += bitStream & 3; |
491 | bitCount += 2; |
492 | if (n0 > *maxSVPtr) return (size_t)-FSE_ERROR_maxSymbolValue_tooSmall; |
493 | while (charnum < n0) normalizedCounter[charnum++] = 0; |
494 | if ((ip <= iend-7) || (ip + (bitCount>>3) <= iend-4)) |
495 | { |
496 | ip += bitCount>>3; |
497 | bitCount &= 7; |
498 | bitStream = FSE_readLE32(ip) >> bitCount; |
499 | } |
500 | else |
501 | bitStream >>= 2; |
502 | } |
503 | { |
504 | const short max = (short)((2*threshold-1)-remaining); |
505 | short count; |
506 | |
507 | if ((bitStream & (threshold-1)) < (U32)max) |
508 | { |
509 | count = (short)(bitStream & (threshold-1)); |
510 | bitCount += nbBits-1; |
511 | } |
512 | else |
513 | { |
514 | count = (short)(bitStream & (2*threshold-1)); |
515 | if (count >= threshold) count -= max; |
516 | bitCount += nbBits; |
517 | } |
518 | |
519 | count--; /* extra accuracy */ |
520 | remaining -= FSE_abs(count); |
521 | normalizedCounter[charnum++] = count; |
522 | previous0 = !count; |
523 | while (remaining < threshold) |
524 | { |
525 | nbBits--; |
526 | threshold >>= 1; |
527 | } |
528 | |
529 | { |
530 | if ((ip <= iend-7) || (ip + (bitCount>>3) <= iend-4)) |
531 | { |
532 | ip += bitCount>>3; |
533 | bitCount &= 7; |
534 | } |
535 | else |
536 | { |
537 | bitCount -= (int)(8 * (iend - 4 - ip)); |
538 | ip = iend - 4; |
539 | } |
540 | bitStream = FSE_readLE32(ip) >> (bitCount & 31); |
541 | } |
542 | } |
543 | } |
544 | if (remaining != 1) return (size_t)-FSE_ERROR_GENERIC; |
545 | *maxSVPtr = charnum-1; |
546 | |
547 | ip += (bitCount+7)>>3; |
548 | if ((size_t)(ip-istart) > hbSize) return (size_t)-FSE_ERROR_srcSize_wrong; |
549 | return ip-istart; |
550 | } |
551 | |
552 | |
553 | /********************************************************* |
554 | * Decompression (Byte symbols) |
555 | *********************************************************/ |
556 | static size_t FSE_buildDTable_rle (FSE_DTable* dt, BYTE symbolValue) |
557 | { |
558 | void* ptr = dt; |
559 | FSE_DTableHeader* const DTableH = (FSE_DTableHeader*)ptr; |
560 | FSE_decode_t* const cell = (FSE_decode_t*)(ptr) + 1; /* because dt is unsigned */ |
561 | |
562 | DTableH->tableLog = 0; |
563 | DTableH->fastMode = 0; |
564 | |
565 | cell->newState = 0; |
566 | cell->symbol = symbolValue; |
567 | cell->nbBits = 0; |
568 | |
569 | return 0; |
570 | } |
571 | |
572 | |
573 | static size_t FSE_buildDTable_raw (FSE_DTable* dt, unsigned nbBits) |
574 | { |
575 | void* ptr = dt; |
576 | FSE_DTableHeader* const DTableH = (FSE_DTableHeader*)ptr; |
577 | FSE_decode_t* const dinfo = (FSE_decode_t*)(ptr) + 1; /* because dt is unsigned */ |
578 | const unsigned tableSize = 1 << nbBits; |
579 | const unsigned tableMask = tableSize - 1; |
580 | const unsigned maxSymbolValue = tableMask; |
581 | unsigned s; |
582 | |
583 | /* Sanity checks */ |
584 | if (nbBits < 1) return (size_t)-FSE_ERROR_GENERIC; /* min size */ |
585 | |
586 | /* Build Decoding Table */ |
587 | DTableH->tableLog = (U16)nbBits; |
588 | DTableH->fastMode = 1; |
589 | for (s=0; s<=maxSymbolValue; s++) |
590 | { |
591 | dinfo[s].newState = 0; |
592 | dinfo[s].symbol = (BYTE)s; |
593 | dinfo[s].nbBits = (BYTE)nbBits; |
594 | } |
595 | |
596 | return 0; |
597 | } |
598 | |
599 | |
600 | /* FSE_initDStream |
601 | * Initialize a FSE_DStream_t. |
602 | * srcBuffer must point at the beginning of an FSE block. |
603 | * The function result is the size of the FSE_block (== srcSize). |
604 | * If srcSize is too small, the function will return an errorCode; |
605 | */ |
606 | static size_t FSE_initDStream(FSE_DStream_t* bitD, const void* srcBuffer, size_t srcSize) |
607 | { |
608 | if (srcSize < 1) return (size_t)-FSE_ERROR_srcSize_wrong; |
609 | |
610 | if (srcSize >= sizeof(size_t)) |
611 | { |
612 | U32 contain32; |
613 | bitD->start = (const char*)srcBuffer; |
614 | bitD->ptr = (const char*)srcBuffer + srcSize - sizeof(size_t); |
615 | bitD->bitContainer = FSE_readLEST(bitD->ptr); |
616 | contain32 = ((const BYTE*)srcBuffer)[srcSize-1]; |
617 | if (contain32 == 0) return (size_t)-FSE_ERROR_GENERIC; /* stop bit not present */ |
618 | bitD->bitsConsumed = 8 - FSE_highbit32(contain32); |
619 | } |
620 | else |
621 | { |
622 | U32 contain32; |
623 | bitD->start = (const char*)srcBuffer; |
624 | bitD->ptr = bitD->start; |
625 | bitD->bitContainer = *(const BYTE*)(bitD->start); |
626 | switch(srcSize) |
627 | { |
628 | case 7: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[6]) << (sizeof(size_t)*8 - 16); |
629 | /* fallthrough */ |
630 | case 6: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[5]) << (sizeof(size_t)*8 - 24); |
631 | /* fallthrough */ |
632 | case 5: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[4]) << (sizeof(size_t)*8 - 32); |
633 | /* fallthrough */ |
634 | case 4: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[3]) << 24; |
635 | /* fallthrough */ |
636 | case 3: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[2]) << 16; |
637 | /* fallthrough */ |
638 | case 2: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[1]) << 8; |
639 | /* fallthrough */ |
640 | default:; |
641 | } |
642 | contain32 = ((const BYTE*)srcBuffer)[srcSize-1]; |
643 | if (contain32 == 0) return (size_t)-FSE_ERROR_GENERIC; /* stop bit not present */ |
644 | bitD->bitsConsumed = 8 - FSE_highbit32(contain32); |
645 | bitD->bitsConsumed += (U32)(sizeof(size_t) - srcSize)*8; |
646 | } |
647 | |
648 | return srcSize; |
649 | } |
650 | |
651 | |
652 | /*!FSE_lookBits |
653 | * Provides next n bits from the bitContainer. |
654 | * bitContainer is not modified (bits are still present for next read/look) |
655 | * On 32-bits, maxNbBits==25 |
656 | * On 64-bits, maxNbBits==57 |
657 | * return : value extracted. |
658 | */ |
659 | static size_t FSE_lookBits(FSE_DStream_t* bitD, U32 nbBits) |
660 | { |
661 | const U32 bitMask = sizeof(bitD->bitContainer)*8 - 1; |
662 | return ((bitD->bitContainer << (bitD->bitsConsumed & bitMask)) >> 1) >> ((bitMask-nbBits) & bitMask); |
663 | } |
664 | |
665 | static size_t FSE_lookBitsFast(FSE_DStream_t* bitD, U32 nbBits) /* only if nbBits >= 1 !! */ |
666 | { |
667 | const U32 bitMask = sizeof(bitD->bitContainer)*8 - 1; |
668 | return (bitD->bitContainer << (bitD->bitsConsumed & bitMask)) >> (((bitMask+1)-nbBits) & bitMask); |
669 | } |
670 | |
671 | static void FSE_skipBits(FSE_DStream_t* bitD, U32 nbBits) |
672 | { |
673 | bitD->bitsConsumed += nbBits; |
674 | } |
675 | |
676 | |
677 | /*!FSE_readBits |
678 | * Read next n bits from the bitContainer. |
679 | * On 32-bits, don't read more than maxNbBits==25 |
680 | * On 64-bits, don't read more than maxNbBits==57 |
681 | * Use the fast variant *only* if n >= 1. |
682 | * return : value extracted. |
683 | */ |
684 | static size_t FSE_readBits(FSE_DStream_t* bitD, U32 nbBits) |
685 | { |
686 | size_t value = FSE_lookBits(bitD, nbBits); |
687 | FSE_skipBits(bitD, nbBits); |
688 | return value; |
689 | } |
690 | |
691 | static size_t FSE_readBitsFast(FSE_DStream_t* bitD, U32 nbBits) /* only if nbBits >= 1 !! */ |
692 | { |
693 | size_t value = FSE_lookBitsFast(bitD, nbBits); |
694 | FSE_skipBits(bitD, nbBits); |
695 | return value; |
696 | } |
697 | |
698 | static unsigned FSE_reloadDStream(FSE_DStream_t* bitD) |
699 | { |
700 | if (bitD->bitsConsumed > (sizeof(bitD->bitContainer)*8)) /* should never happen */ |
701 | return FSE_DStream_tooFar; |
702 | |
703 | if (bitD->ptr >= bitD->start + sizeof(bitD->bitContainer)) |
704 | { |
705 | bitD->ptr -= bitD->bitsConsumed >> 3; |
706 | bitD->bitsConsumed &= 7; |
707 | bitD->bitContainer = FSE_readLEST(bitD->ptr); |
708 | return FSE_DStream_unfinished; |
709 | } |
710 | if (bitD->ptr == bitD->start) |
711 | { |
712 | if (bitD->bitsConsumed < sizeof(bitD->bitContainer)*8) return FSE_DStream_endOfBuffer; |
713 | return FSE_DStream_completed; |
714 | } |
715 | { |
716 | U32 nbBytes = bitD->bitsConsumed >> 3; |
717 | U32 result = FSE_DStream_unfinished; |
718 | if (bitD->ptr - nbBytes < bitD->start) |
719 | { |
720 | nbBytes = (U32)(bitD->ptr - bitD->start); /* ptr > start */ |
721 | result = FSE_DStream_endOfBuffer; |
722 | } |
723 | bitD->ptr -= nbBytes; |
724 | bitD->bitsConsumed -= nbBytes*8; |
725 | bitD->bitContainer = FSE_readLEST(bitD->ptr); /* reminder : srcSize > sizeof(bitD) */ |
726 | return result; |
727 | } |
728 | } |
729 | |
730 | |
731 | static void FSE_initDState(FSE_DState_t* DStatePtr, FSE_DStream_t* bitD, const FSE_DTable* dt) |
732 | { |
733 | const void* ptr = dt; |
734 | const FSE_DTableHeader* const DTableH = (const FSE_DTableHeader*)ptr; |
735 | DStatePtr->state = FSE_readBits(bitD, DTableH->tableLog); |
736 | FSE_reloadDStream(bitD); |
737 | DStatePtr->table = dt + 1; |
738 | } |
739 | |
740 | static BYTE FSE_decodeSymbol(FSE_DState_t* DStatePtr, FSE_DStream_t* bitD) |
741 | { |
742 | const FSE_decode_t DInfo = ((const FSE_decode_t*)(DStatePtr->table))[DStatePtr->state]; |
743 | const U32 nbBits = DInfo.nbBits; |
744 | BYTE symbol = DInfo.symbol; |
745 | size_t lowBits = FSE_readBits(bitD, nbBits); |
746 | |
747 | DStatePtr->state = DInfo.newState + lowBits; |
748 | return symbol; |
749 | } |
750 | |
751 | static BYTE FSE_decodeSymbolFast(FSE_DState_t* DStatePtr, FSE_DStream_t* bitD) |
752 | { |
753 | const FSE_decode_t DInfo = ((const FSE_decode_t*)(DStatePtr->table))[DStatePtr->state]; |
754 | const U32 nbBits = DInfo.nbBits; |
755 | BYTE symbol = DInfo.symbol; |
756 | size_t lowBits = FSE_readBitsFast(bitD, nbBits); |
757 | |
758 | DStatePtr->state = DInfo.newState + lowBits; |
759 | return symbol; |
760 | } |
761 | |
762 | /* FSE_endOfDStream |
763 | Tells if bitD has reached end of bitStream or not */ |
764 | |
765 | static unsigned FSE_endOfDStream(const FSE_DStream_t* bitD) |
766 | { |
767 | return ((bitD->ptr == bitD->start) && (bitD->bitsConsumed == sizeof(bitD->bitContainer)*8)); |
768 | } |
769 | |
770 | static unsigned FSE_endOfDState(const FSE_DState_t* DStatePtr) |
771 | { |
772 | return DStatePtr->state == 0; |
773 | } |
774 | |
775 | |
776 | FORCE_INLINE size_t FSE_decompress_usingDTable_generic( |
777 | void* dst, size_t maxDstSize, |
778 | const void* cSrc, size_t cSrcSize, |
779 | const FSE_DTable* dt, const unsigned fast) |
780 | { |
781 | BYTE* const ostart = (BYTE*) dst; |
782 | BYTE* op = ostart; |
783 | BYTE* const omax = op + maxDstSize; |
784 | BYTE* const olimit = omax-3; |
785 | |
786 | FSE_DStream_t bitD; |
787 | FSE_DState_t state1; |
788 | FSE_DState_t state2; |
789 | size_t errorCode; |
790 | |
791 | /* Init */ |
792 | errorCode = FSE_initDStream(&bitD, cSrc, cSrcSize); /* replaced last arg by maxCompressed Size */ |
793 | if (FSE_isError(errorCode)) return errorCode; |
794 | |
795 | FSE_initDState(&state1, &bitD, dt); |
796 | FSE_initDState(&state2, &bitD, dt); |
797 | |
798 | #define FSE_GETSYMBOL(statePtr) fast ? FSE_decodeSymbolFast(statePtr, &bitD) : FSE_decodeSymbol(statePtr, &bitD) |
799 | |
800 | /* 4 symbols per loop */ |
801 | for ( ; (FSE_reloadDStream(&bitD)==FSE_DStream_unfinished) && (op<olimit) ; op+=4) |
802 | { |
803 | op[0] = FSE_GETSYMBOL(&state1); |
804 | |
805 | if (FSE_MAX_TABLELOG*2+7 > sizeof(bitD.bitContainer)*8) /* This test must be static */ |
806 | FSE_reloadDStream(&bitD); |
807 | |
808 | op[1] = FSE_GETSYMBOL(&state2); |
809 | |
810 | if (FSE_MAX_TABLELOG*4+7 > sizeof(bitD.bitContainer)*8) /* This test must be static */ |
811 | { if (FSE_reloadDStream(&bitD) > FSE_DStream_unfinished) { op+=2; break; } } |
812 | |
813 | op[2] = FSE_GETSYMBOL(&state1); |
814 | |
815 | if (FSE_MAX_TABLELOG*2+7 > sizeof(bitD.bitContainer)*8) /* This test must be static */ |
816 | FSE_reloadDStream(&bitD); |
817 | |
818 | op[3] = FSE_GETSYMBOL(&state2); |
819 | } |
820 | |
821 | /* tail */ |
822 | /* note : FSE_reloadDStream(&bitD) >= FSE_DStream_partiallyFilled; Ends at exactly FSE_DStream_completed */ |
823 | while (1) |
824 | { |
825 | if ( (FSE_reloadDStream(&bitD)>FSE_DStream_completed) || (op==omax) || (FSE_endOfDStream(&bitD) && (fast || FSE_endOfDState(&state1))) ) |
826 | break; |
827 | |
828 | *op++ = FSE_GETSYMBOL(&state1); |
829 | |
830 | if ( (FSE_reloadDStream(&bitD)>FSE_DStream_completed) || (op==omax) || (FSE_endOfDStream(&bitD) && (fast || FSE_endOfDState(&state2))) ) |
831 | break; |
832 | |
833 | *op++ = FSE_GETSYMBOL(&state2); |
834 | } |
835 | |
836 | /* end ? */ |
837 | if (FSE_endOfDStream(&bitD) && FSE_endOfDState(&state1) && FSE_endOfDState(&state2)) |
838 | return op-ostart; |
839 | |
840 | if (op==omax) return (size_t)-FSE_ERROR_dstSize_tooSmall; /* dst buffer is full, but cSrc unfinished */ |
841 | |
842 | return (size_t)-FSE_ERROR_corruptionDetected; |
843 | } |
844 | |
845 | |
846 | static size_t FSE_decompress_usingDTable(void* dst, size_t originalSize, |
847 | const void* cSrc, size_t cSrcSize, |
848 | const FSE_DTable* dt) |
849 | { |
850 | FSE_DTableHeader DTableH; |
851 | memcpy(&DTableH, dt, sizeof(DTableH)); /* memcpy() into local variable, to avoid strict aliasing warning */ |
852 | |
853 | /* select fast mode (static) */ |
854 | if (DTableH.fastMode) return FSE_decompress_usingDTable_generic(dst, originalSize, cSrc, cSrcSize, dt, 1); |
855 | return FSE_decompress_usingDTable_generic(dst, originalSize, cSrc, cSrcSize, dt, 0); |
856 | } |
857 | |
858 | |
859 | static size_t FSE_decompress(void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize) |
860 | { |
861 | const BYTE* const istart = (const BYTE*)cSrc; |
862 | const BYTE* ip = istart; |
863 | short counting[FSE_MAX_SYMBOL_VALUE+1]; |
864 | DTable_max_t dt; /* Static analyzer seems unable to understand this table will be properly initialized later */ |
865 | unsigned tableLog; |
866 | unsigned maxSymbolValue = FSE_MAX_SYMBOL_VALUE; |
867 | size_t errorCode; |
868 | |
869 | if (cSrcSize<2) return (size_t)-FSE_ERROR_srcSize_wrong; /* too small input size */ |
870 | |
871 | /* normal FSE decoding mode */ |
872 | errorCode = FSE_readNCount (counting, &maxSymbolValue, &tableLog, istart, cSrcSize); |
873 | if (FSE_isError(errorCode)) return errorCode; |
874 | if (errorCode >= cSrcSize) return (size_t)-FSE_ERROR_srcSize_wrong; /* too small input size */ |
875 | ip += errorCode; |
876 | cSrcSize -= errorCode; |
877 | |
878 | errorCode = FSE_buildDTable (dt, counting, maxSymbolValue, tableLog); |
879 | if (FSE_isError(errorCode)) return errorCode; |
880 | |
881 | /* always return, even if it is an error code */ |
882 | return FSE_decompress_usingDTable (dst, maxDstSize, ip, cSrcSize, dt); |
883 | } |
884 | |
885 | |
886 | |
887 | /* ******************************************************* |
888 | * Huff0 : Huffman block compression |
889 | *********************************************************/ |
890 | #define HUF_MAX_SYMBOL_VALUE 255 |
891 | #define HUF_DEFAULT_TABLELOG 12 /* used by default, when not specified */ |
892 | #define HUF_MAX_TABLELOG 12 /* max possible tableLog; for allocation purpose; can be modified */ |
893 | #define HUF_ABSOLUTEMAX_TABLELOG 16 /* absolute limit of HUF_MAX_TABLELOG. Beyond that value, code does not work */ |
894 | #if (HUF_MAX_TABLELOG > HUF_ABSOLUTEMAX_TABLELOG) |
895 | # error "HUF_MAX_TABLELOG is too large !" |
896 | #endif |
897 | |
898 | typedef struct HUF_CElt_s { |
899 | U16 val; |
900 | BYTE nbBits; |
901 | } HUF_CElt ; |
902 | |
903 | typedef struct nodeElt_s { |
904 | U32 count; |
905 | U16 parent; |
906 | BYTE byte; |
907 | BYTE nbBits; |
908 | } nodeElt; |
909 | |
910 | |
911 | /* ******************************************************* |
912 | * Huff0 : Huffman block decompression |
913 | *********************************************************/ |
914 | typedef struct { |
915 | BYTE byte; |
916 | BYTE nbBits; |
917 | } HUF_DElt; |
918 | |
919 | static size_t HUF_readDTable (U16* DTable, const void* src, size_t srcSize) |
920 | { |
921 | BYTE huffWeight[HUF_MAX_SYMBOL_VALUE + 1]; |
922 | U32 rankVal[HUF_ABSOLUTEMAX_TABLELOG + 1]; /* large enough for values from 0 to 16 */ |
923 | U32 weightTotal; |
924 | U32 maxBits; |
925 | const BYTE* ip = (const BYTE*) src; |
926 | size_t iSize; |
927 | size_t oSize; |
928 | U32 n; |
929 | U32 nextRankStart; |
930 | void* ptr = DTable+1; |
931 | HUF_DElt* const dt = (HUF_DElt*)ptr; |
932 | |
933 | if (!srcSize) return (size_t)-FSE_ERROR_srcSize_wrong; |
934 | iSize = ip[0]; |
935 | |
936 | FSE_STATIC_ASSERT(sizeof(HUF_DElt) == sizeof(U16)); /* if compilation fails here, assertion is false */ |
937 | //memset(huffWeight, 0, sizeof(huffWeight)); /* should not be necessary, but some analyzer complain ... */ |
938 | if (iSize >= 128) /* special header */ |
939 | { |
940 | if (iSize >= (242)) /* RLE */ |
941 | { |
942 | static int l[14] = { 1, 2, 3, 4, 7, 8, 15, 16, 31, 32, 63, 64, 127, 128 }; |
943 | oSize = l[iSize-242]; |
944 | memset(huffWeight, 1, sizeof(huffWeight)); |
945 | iSize = 0; |
946 | } |
947 | else /* Incompressible */ |
948 | { |
949 | oSize = iSize - 127; |
950 | iSize = ((oSize+1)/2); |
951 | if (iSize+1 > srcSize) return (size_t)-FSE_ERROR_srcSize_wrong; |
952 | ip += 1; |
953 | for (n=0; n<oSize; n+=2) |
954 | { |
955 | huffWeight[n] = ip[n/2] >> 4; |
956 | huffWeight[n+1] = ip[n/2] & 15; |
957 | } |
958 | } |
959 | } |
960 | else /* header compressed with FSE (normal case) */ |
961 | { |
962 | if (iSize+1 > srcSize) return (size_t)-FSE_ERROR_srcSize_wrong; |
963 | oSize = FSE_decompress(huffWeight, HUF_MAX_SYMBOL_VALUE, ip+1, iSize); /* max 255 values decoded, last one is implied */ |
964 | if (FSE_isError(oSize)) return oSize; |
965 | } |
966 | |
967 | /* collect weight stats */ |
968 | memset(rankVal, 0, sizeof(rankVal)); |
969 | weightTotal = 0; |
970 | for (n=0; n<oSize; n++) |
971 | { |
972 | if (huffWeight[n] >= HUF_ABSOLUTEMAX_TABLELOG) return (size_t)-FSE_ERROR_corruptionDetected; |
973 | rankVal[huffWeight[n]]++; |
974 | weightTotal += (1 << huffWeight[n]) >> 1; |
975 | } |
976 | if (weightTotal == 0) return (size_t)-FSE_ERROR_corruptionDetected; |
977 | |
978 | /* get last non-null symbol weight (implied, total must be 2^n) */ |
979 | maxBits = FSE_highbit32(weightTotal) + 1; |
980 | if (maxBits > DTable[0]) return (size_t)-FSE_ERROR_tableLog_tooLarge; /* DTable is too small */ |
981 | DTable[0] = (U16)maxBits; |
982 | { |
983 | U32 total = 1 << maxBits; |
984 | U32 rest = total - weightTotal; |
985 | U32 verif = 1 << FSE_highbit32(rest); |
986 | U32 lastWeight = FSE_highbit32(rest) + 1; |
987 | if (verif != rest) return (size_t)-FSE_ERROR_corruptionDetected; /* last value must be a clean power of 2 */ |
988 | huffWeight[oSize] = (BYTE)lastWeight; |
989 | rankVal[lastWeight]++; |
990 | } |
991 | |
992 | /* check tree construction validity */ |
993 | 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 */ |
994 | |
995 | /* Prepare ranks */ |
996 | nextRankStart = 0; |
997 | for (n=1; n<=maxBits; n++) |
998 | { |
999 | U32 current = nextRankStart; |
1000 | nextRankStart += (rankVal[n] << (n-1)); |
1001 | rankVal[n] = current; |
1002 | } |
1003 | |
1004 | /* fill DTable */ |
1005 | for (n=0; n<=oSize; n++) |
1006 | { |
1007 | const U32 w = huffWeight[n]; |
1008 | const U32 length = (1 << w) >> 1; |
1009 | U32 i; |
1010 | HUF_DElt D; |
1011 | D.byte = (BYTE)n; D.nbBits = (BYTE)(maxBits + 1 - w); |
1012 | for (i = rankVal[w]; i < rankVal[w] + length; i++) |
1013 | dt[i] = D; |
1014 | rankVal[w] += length; |
1015 | } |
1016 | |
1017 | return iSize+1; |
1018 | } |
1019 | |
1020 | |
1021 | static BYTE HUF_decodeSymbol(FSE_DStream_t* Dstream, const HUF_DElt* dt, const U32 dtLog) |
1022 | { |
1023 | const size_t val = FSE_lookBitsFast(Dstream, dtLog); /* note : dtLog >= 1 */ |
1024 | const BYTE c = dt[val].byte; |
1025 | FSE_skipBits(Dstream, dt[val].nbBits); |
1026 | return c; |
1027 | } |
1028 | |
1029 | static size_t HUF_decompress_usingDTable( /* -3% slower when non static */ |
1030 | void* dst, size_t maxDstSize, |
1031 | const void* cSrc, size_t cSrcSize, |
1032 | const U16* DTable) |
1033 | { |
1034 | if (cSrcSize < 6) return (size_t)-FSE_ERROR_srcSize_wrong; |
1035 | { |
1036 | BYTE* const ostart = (BYTE*) dst; |
1037 | BYTE* op = ostart; |
1038 | BYTE* const omax = op + maxDstSize; |
1039 | BYTE* const olimit = maxDstSize < 15 ? op : omax-15; |
1040 | |
1041 | const void* ptr = DTable; |
1042 | const HUF_DElt* const dt = (const HUF_DElt*)(ptr)+1; |
1043 | const U32 dtLog = DTable[0]; |
1044 | size_t errorCode; |
1045 | U32 reloadStatus; |
1046 | |
1047 | /* Init */ |
1048 | |
1049 | const U16* jumpTable = (const U16*)cSrc; |
1050 | const size_t length1 = FSE_readLE16(jumpTable); |
1051 | const size_t length2 = FSE_readLE16(jumpTable+1); |
1052 | const size_t length3 = FSE_readLE16(jumpTable+2); |
1053 | const size_t length4 = cSrcSize - 6 - length1 - length2 - length3; /* check coherency !! */ |
1054 | const char* const start1 = (const char*)(cSrc) + 6; |
1055 | const char* const start2 = start1 + length1; |
1056 | const char* const start3 = start2 + length2; |
1057 | const char* const start4 = start3 + length3; |
1058 | FSE_DStream_t bitD1, bitD2, bitD3, bitD4; |
1059 | |
1060 | if (length1+length2+length3+6 >= cSrcSize) return (size_t)-FSE_ERROR_srcSize_wrong; |
1061 | |
1062 | errorCode = FSE_initDStream(&bitD1, start1, length1); |
1063 | if (FSE_isError(errorCode)) return errorCode; |
1064 | errorCode = FSE_initDStream(&bitD2, start2, length2); |
1065 | if (FSE_isError(errorCode)) return errorCode; |
1066 | errorCode = FSE_initDStream(&bitD3, start3, length3); |
1067 | if (FSE_isError(errorCode)) return errorCode; |
1068 | errorCode = FSE_initDStream(&bitD4, start4, length4); |
1069 | if (FSE_isError(errorCode)) return errorCode; |
1070 | |
1071 | reloadStatus=FSE_reloadDStream(&bitD2); |
1072 | |
1073 | /* 16 symbols per loop */ |
1074 | for ( ; (reloadStatus<FSE_DStream_completed) && (op<olimit); /* D2-3-4 are supposed to be synchronized and finish together */ |
1075 | op+=16, reloadStatus = FSE_reloadDStream(&bitD2) | FSE_reloadDStream(&bitD3) | FSE_reloadDStream(&bitD4), FSE_reloadDStream(&bitD1)) |
1076 | { |
1077 | #define HUF_DECODE_SYMBOL_0(n, Dstream) \ |
1078 | op[n] = HUF_decodeSymbol(&Dstream, dt, dtLog); |
1079 | |
1080 | #define HUF_DECODE_SYMBOL_1(n, Dstream) \ |
1081 | op[n] = HUF_decodeSymbol(&Dstream, dt, dtLog); \ |
1082 | if (FSE_32bits() && (HUF_MAX_TABLELOG>12)) FSE_reloadDStream(&Dstream) |
1083 | |
1084 | #define HUF_DECODE_SYMBOL_2(n, Dstream) \ |
1085 | op[n] = HUF_decodeSymbol(&Dstream, dt, dtLog); \ |
1086 | if (FSE_32bits()) FSE_reloadDStream(&Dstream) |
1087 | |
1088 | HUF_DECODE_SYMBOL_1( 0, bitD1); |
1089 | HUF_DECODE_SYMBOL_1( 1, bitD2); |
1090 | HUF_DECODE_SYMBOL_1( 2, bitD3); |
1091 | HUF_DECODE_SYMBOL_1( 3, bitD4); |
1092 | HUF_DECODE_SYMBOL_2( 4, bitD1); |
1093 | HUF_DECODE_SYMBOL_2( 5, bitD2); |
1094 | HUF_DECODE_SYMBOL_2( 6, bitD3); |
1095 | HUF_DECODE_SYMBOL_2( 7, bitD4); |
1096 | HUF_DECODE_SYMBOL_1( 8, bitD1); |
1097 | HUF_DECODE_SYMBOL_1( 9, bitD2); |
1098 | HUF_DECODE_SYMBOL_1(10, bitD3); |
1099 | HUF_DECODE_SYMBOL_1(11, bitD4); |
1100 | HUF_DECODE_SYMBOL_0(12, bitD1); |
1101 | HUF_DECODE_SYMBOL_0(13, bitD2); |
1102 | HUF_DECODE_SYMBOL_0(14, bitD3); |
1103 | HUF_DECODE_SYMBOL_0(15, bitD4); |
1104 | } |
1105 | |
1106 | if (reloadStatus!=FSE_DStream_completed) /* not complete : some bitStream might be FSE_DStream_unfinished */ |
1107 | return (size_t)-FSE_ERROR_corruptionDetected; |
1108 | |
1109 | /* tail */ |
1110 | { |
1111 | /* bitTail = bitD1; */ /* *much* slower : -20% !??! */ |
1112 | FSE_DStream_t bitTail; |
1113 | bitTail.ptr = bitD1.ptr; |
1114 | bitTail.bitsConsumed = bitD1.bitsConsumed; |
1115 | bitTail.bitContainer = bitD1.bitContainer; /* required in case of FSE_DStream_endOfBuffer */ |
1116 | bitTail.start = start1; |
1117 | for ( ; (FSE_reloadDStream(&bitTail) < FSE_DStream_completed) && (op<omax) ; op++) |
1118 | { |
1119 | HUF_DECODE_SYMBOL_0(0, bitTail); |
1120 | } |
1121 | |
1122 | if (FSE_endOfDStream(&bitTail)) |
1123 | return op-ostart; |
1124 | } |
1125 | |
1126 | if (op==omax) return (size_t)-FSE_ERROR_dstSize_tooSmall; /* dst buffer is full, but cSrc unfinished */ |
1127 | |
1128 | return (size_t)-FSE_ERROR_corruptionDetected; |
1129 | } |
1130 | } |
1131 | |
1132 | |
1133 | static size_t HUF_decompress (void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize) |
1134 | { |
1135 | HUF_CREATE_STATIC_DTABLE(DTable, HUF_MAX_TABLELOG); |
1136 | const BYTE* ip = (const BYTE*) cSrc; |
1137 | size_t errorCode; |
1138 | |
1139 | errorCode = HUF_readDTable (DTable, cSrc, cSrcSize); |
1140 | if (FSE_isError(errorCode)) return errorCode; |
1141 | if (errorCode >= cSrcSize) return (size_t)-FSE_ERROR_srcSize_wrong; |
1142 | ip += errorCode; |
1143 | cSrcSize -= errorCode; |
1144 | |
1145 | return HUF_decompress_usingDTable (dst, maxDstSize, ip, cSrcSize, DTable); |
1146 | } |
1147 | |
1148 | |
1149 | #endif /* FSE_COMMONDEFS_ONLY */ |
1150 | |
1151 | /* |
1152 | zstd - standard compression library |
1153 | Copyright (C) 2014-2015, Yann Collet. |
1154 | |
1155 | BSD 2-Clause License (https://opensource.org/licenses/bsd-license.php) |
1156 | |
1157 | Redistribution and use in source and binary forms, with or without |
1158 | modification, are permitted provided that the following conditions are |
1159 | met: |
1160 | * Redistributions of source code must retain the above copyright |
1161 | notice, this list of conditions and the following disclaimer. |
1162 | * Redistributions in binary form must reproduce the above |
1163 | copyright notice, this list of conditions and the following disclaimer |
1164 | in the documentation and/or other materials provided with the |
1165 | distribution. |
1166 | THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
1167 | "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
1168 | LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
1169 | A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
1170 | OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
1171 | SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
1172 | LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
1173 | DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
1174 | THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
1175 | (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
1176 | OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
1177 | |
1178 | You can contact the author at : |
1179 | - zstd source repository : https://github.com/Cyan4973/zstd |
1180 | - ztsd public forum : https://groups.google.com/forum/#!forum/lz4c |
1181 | */ |
1182 | |
1183 | /**************************************************************** |
1184 | * Tuning parameters |
1185 | *****************************************************************/ |
1186 | /* MEMORY_USAGE : |
1187 | * Memory usage formula : N->2^N Bytes (examples : 10 -> 1KB; 12 -> 4KB ; 16 -> 64KB; 20 -> 1MB; etc.) |
1188 | * Increasing memory usage improves compression ratio |
1189 | * Reduced memory usage can improve speed, due to cache effect */ |
1190 | #define ZSTD_MEMORY_USAGE 17 |
1191 | |
1192 | |
1193 | /************************************** |
1194 | CPU Feature Detection |
1195 | **************************************/ |
1196 | /* |
1197 | * Automated efficient unaligned memory access detection |
1198 | * Based on known hardware architectures |
1199 | * This list will be updated thanks to feedbacks |
1200 | */ |
1201 | #if defined(CPU_HAS_EFFICIENT_UNALIGNED_MEMORY_ACCESS) \ |
1202 | || defined(__ARM_FEATURE_UNALIGNED) \ |
1203 | || defined(__i386__) || defined(__x86_64__) \ |
1204 | || defined(_M_IX86) || defined(_M_X64) \ |
1205 | || defined(__ARM_ARCH_7__) || defined(__ARM_ARCH_8__) \ |
1206 | || (defined(_M_ARM) && (_M_ARM >= 7)) |
1207 | # define ZSTD_UNALIGNED_ACCESS 1 |
1208 | #else |
1209 | # define ZSTD_UNALIGNED_ACCESS 0 |
1210 | #endif |
1211 | |
1212 | |
1213 | /******************************************************** |
1214 | * Includes |
1215 | *********************************************************/ |
1216 | #include <stdlib.h> /* calloc */ |
1217 | #include <string.h> /* memcpy, memmove */ |
1218 | #include <stdio.h> /* debug : printf */ |
1219 | |
1220 | |
1221 | /******************************************************** |
1222 | * Compiler specifics |
1223 | *********************************************************/ |
1224 | #ifdef __AVX2__ |
1225 | # include <immintrin.h> /* AVX2 intrinsics */ |
1226 | #endif |
1227 | |
1228 | #ifdef _MSC_VER /* Visual Studio */ |
1229 | # include <intrin.h> /* For Visual 2005 */ |
1230 | # pragma warning(disable : 4127) /* disable: C4127: conditional expression is constant */ |
1231 | # pragma warning(disable : 4324) /* disable: C4324: padded structure */ |
1232 | #endif |
1233 | |
1234 | |
1235 | #ifndef MEM_ACCESS_MODULE |
1236 | #define MEM_ACCESS_MODULE |
1237 | /******************************************************** |
1238 | * Basic Types |
1239 | *********************************************************/ |
1240 | #if defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L /* C99 */ |
1241 | # if defined(_AIX) |
1242 | # include <inttypes.h> |
1243 | # else |
1244 | # include <stdint.h> /* intptr_t */ |
1245 | # endif |
1246 | typedef uint8_t BYTE; |
1247 | typedef uint16_t U16; |
1248 | typedef int16_t S16; |
1249 | typedef uint32_t U32; |
1250 | typedef int32_t S32; |
1251 | typedef uint64_t U64; |
1252 | #else |
1253 | typedef unsigned char BYTE; |
1254 | typedef unsigned short U16; |
1255 | typedef signed short S16; |
1256 | typedef unsigned int U32; |
1257 | typedef signed int S32; |
1258 | typedef unsigned long long U64; |
1259 | #endif |
1260 | |
1261 | #endif /* MEM_ACCESS_MODULE */ |
1262 | |
1263 | |
1264 | /******************************************************** |
1265 | * Constants |
1266 | *********************************************************/ |
1267 | static const U32 ZSTD_magicNumber = 0xFD2FB51E; /* 3rd version : seqNb header */ |
1268 | |
1269 | #define HASH_LOG (ZSTD_MEMORY_USAGE - 2) |
1270 | #define HASH_TABLESIZE (1 << HASH_LOG) |
1271 | #define HASH_MASK (HASH_TABLESIZE - 1) |
1272 | |
1273 | #define KNUTH 2654435761 |
1274 | |
1275 | #define BIT7 128 |
1276 | #define BIT6 64 |
1277 | #define BIT5 32 |
1278 | #define BIT4 16 |
1279 | |
1280 | #define KB *(1 <<10) |
1281 | #define MB *(1 <<20) |
1282 | #define GB *(1U<<30) |
1283 | |
1284 | #define BLOCKSIZE (128 KB) /* define, for static allocation */ |
1285 | |
1286 | #define WORKPLACESIZE (BLOCKSIZE*3) |
1287 | #define MINMATCH 4 |
1288 | #define MLbits 7 |
1289 | #define LLbits 6 |
1290 | #define Offbits 5 |
1291 | #define MaxML ((1<<MLbits )-1) |
1292 | #define MaxLL ((1<<LLbits )-1) |
1293 | #define MaxOff ((1<<Offbits)-1) |
1294 | #define LitFSELog 11 |
1295 | #define MLFSELog 10 |
1296 | #define LLFSELog 10 |
1297 | #define OffFSELog 9 |
1298 | #define MAX(a,b) ((a)<(b)?(b):(a)) |
1299 | #define MaxSeq MAX(MaxLL, MaxML) |
1300 | |
1301 | #define LITERAL_NOENTROPY 63 |
1302 | #define COMMAND_NOENTROPY 7 /* to remove */ |
1303 | |
1304 | #define ZSTD_CONTENTSIZE_ERROR (0ULL - 2) |
1305 | |
1306 | static const size_t ZSTD_blockHeaderSize = 3; |
1307 | static const size_t ZSTD_frameHeaderSize = 4; |
1308 | |
1309 | |
1310 | /******************************************************** |
1311 | * Memory operations |
1312 | *********************************************************/ |
1313 | static unsigned ZSTD_32bits(void) { return sizeof(void*)==4; } |
1314 | |
1315 | static unsigned ZSTD_isLittleEndian(void) |
1316 | { |
1317 | const union { U32 i; BYTE c[4]; } one = { 1 }; /* don't use static : performance detrimental */ |
1318 | return one.c[0]; |
1319 | } |
1320 | |
1321 | static U16 ZSTD_read16(const void* p) { U16 r; memcpy(&r, p, sizeof(r)); return r; } |
1322 | |
1323 | static void ZSTD_copy4(void* dst, const void* src) { memcpy(dst, src, 4); } |
1324 | |
1325 | static void ZSTD_copy8(void* dst, const void* src) { memcpy(dst, src, 8); } |
1326 | |
1327 | #define COPY8(d,s) { ZSTD_copy8(d,s); d+=8; s+=8; } |
1328 | |
1329 | static void ZSTD_wildcopy(void* dst, const void* src, ptrdiff_t length) |
1330 | { |
1331 | const BYTE* ip = (const BYTE*)src; |
1332 | BYTE* op = (BYTE*)dst; |
1333 | BYTE* const oend = op + length; |
1334 | while (op < oend) COPY8(op, ip); |
1335 | } |
1336 | |
1337 | static U16 ZSTD_readLE16(const void* memPtr) |
1338 | { |
1339 | if (ZSTD_isLittleEndian()) return ZSTD_read16(memPtr); |
1340 | else |
1341 | { |
1342 | const BYTE* p = (const BYTE*)memPtr; |
1343 | return (U16)((U16)p[0] + ((U16)p[1]<<8)); |
1344 | } |
1345 | } |
1346 | |
1347 | static U32 ZSTD_readLE24(const void* memPtr) |
1348 | { |
1349 | return ZSTD_readLE16(memPtr) + (((const BYTE*)memPtr)[2] << 16); |
1350 | } |
1351 | |
1352 | static U32 ZSTD_readBE32(const void* memPtr) |
1353 | { |
1354 | const BYTE* p = (const BYTE*)memPtr; |
1355 | return (U32)(((U32)p[0]<<24) + ((U32)p[1]<<16) + ((U32)p[2]<<8) + ((U32)p[3]<<0)); |
1356 | } |
1357 | |
1358 | |
1359 | /************************************** |
1360 | * Local structures |
1361 | ***************************************/ |
1362 | typedef struct ZSTD_Cctx_s ZSTD_Cctx; |
1363 | |
1364 | typedef enum { bt_compressed, bt_raw, bt_rle, bt_end } blockType_t; |
1365 | |
1366 | typedef struct |
1367 | { |
1368 | blockType_t blockType; |
1369 | U32 origSize; |
1370 | } blockProperties_t; |
1371 | |
1372 | typedef struct { |
1373 | void* buffer; |
1374 | U32* offsetStart; |
1375 | U32* offset; |
1376 | BYTE* offCodeStart; |
1377 | BYTE* offCode; |
1378 | BYTE* litStart; |
1379 | BYTE* lit; |
1380 | BYTE* litLengthStart; |
1381 | BYTE* litLength; |
1382 | BYTE* matchLengthStart; |
1383 | BYTE* matchLength; |
1384 | BYTE* dumpsStart; |
1385 | BYTE* dumps; |
1386 | } seqStore_t; |
1387 | |
1388 | |
1389 | typedef struct ZSTD_Cctx_s |
1390 | { |
1391 | const BYTE* base; |
1392 | U32 current; |
1393 | U32 nextUpdate; |
1394 | seqStore_t seqStore; |
1395 | #ifdef __AVX2__ |
1396 | __m256i hashTable[HASH_TABLESIZE>>3]; |
1397 | #else |
1398 | U32 hashTable[HASH_TABLESIZE]; |
1399 | #endif |
1400 | BYTE buffer[WORKPLACESIZE]; |
1401 | } cctxi_t; |
1402 | |
1403 | |
1404 | |
1405 | |
1406 | /************************************** |
1407 | * Error Management |
1408 | **************************************/ |
1409 | /* published entry point */ |
1410 | unsigned ZSTDv01_isError(size_t code) { return ERR_isError(code); } |
1411 | |
1412 | |
1413 | /************************************** |
1414 | * Tool functions |
1415 | **************************************/ |
1416 | #define ZSTD_VERSION_MAJOR 0 /* for breaking interface changes */ |
1417 | #define ZSTD_VERSION_MINOR 1 /* for new (non-breaking) interface capabilities */ |
1418 | #define ZSTD_VERSION_RELEASE 3 /* for tweaks, bug-fixes, or development */ |
1419 | #define ZSTD_VERSION_NUMBER (ZSTD_VERSION_MAJOR *100*100 + ZSTD_VERSION_MINOR *100 + ZSTD_VERSION_RELEASE) |
1420 | |
1421 | /************************************************************** |
1422 | * Decompression code |
1423 | **************************************************************/ |
1424 | |
1425 | static size_t ZSTDv01_getcBlockSize(const void* src, size_t srcSize, blockProperties_t* bpPtr) |
1426 | { |
1427 | const BYTE* const in = (const BYTE* const)src; |
1428 | BYTE headerFlags; |
1429 | U32 cSize; |
1430 | |
1431 | if (srcSize < 3) return ERROR(srcSize_wrong); |
1432 | |
1433 | headerFlags = *in; |
1434 | cSize = in[2] + (in[1]<<8) + ((in[0] & 7)<<16); |
1435 | |
1436 | bpPtr->blockType = (blockType_t)(headerFlags >> 6); |
1437 | bpPtr->origSize = (bpPtr->blockType == bt_rle) ? cSize : 0; |
1438 | |
1439 | if (bpPtr->blockType == bt_end) return 0; |
1440 | if (bpPtr->blockType == bt_rle) return 1; |
1441 | return cSize; |
1442 | } |
1443 | |
1444 | |
1445 | static size_t ZSTD_copyUncompressedBlock(void* dst, size_t maxDstSize, const void* src, size_t srcSize) |
1446 | { |
1447 | if (srcSize > maxDstSize) return ERROR(dstSize_tooSmall); |
1448 | if (srcSize > 0) { |
1449 | memcpy(dst, src, srcSize); |
1450 | } |
1451 | return srcSize; |
1452 | } |
1453 | |
1454 | |
1455 | static size_t ZSTD_decompressLiterals(void* ctx, |
1456 | void* dst, size_t maxDstSize, |
1457 | const void* src, size_t srcSize) |
1458 | { |
1459 | BYTE* op = (BYTE*)dst; |
1460 | BYTE* const oend = op + maxDstSize; |
1461 | const BYTE* ip = (const BYTE*)src; |
1462 | size_t errorCode; |
1463 | size_t litSize; |
1464 | |
1465 | /* check : minimum 2, for litSize, +1, for content */ |
1466 | if (srcSize <= 3) return ERROR(corruption_detected); |
1467 | |
1468 | litSize = ip[1] + (ip[0]<<8); |
1469 | litSize += ((ip[-3] >> 3) & 7) << 16; /* mmmmh.... */ |
1470 | op = oend - litSize; |
1471 | |
1472 | (void)ctx; |
1473 | if (litSize > maxDstSize) return ERROR(dstSize_tooSmall); |
1474 | errorCode = HUF_decompress(op, litSize, ip+2, srcSize-2); |
1475 | if (FSE_isError(errorCode)) return ERROR(GENERIC); |
1476 | return litSize; |
1477 | } |
1478 | |
1479 | |
1480 | static size_t ZSTDv01_decodeLiteralsBlock(void* ctx, |
1481 | void* dst, size_t maxDstSize, |
1482 | const BYTE** litStart, size_t* litSize, |
1483 | const void* src, size_t srcSize) |
1484 | { |
1485 | const BYTE* const istart = (const BYTE* const)src; |
1486 | const BYTE* ip = istart; |
1487 | BYTE* const ostart = (BYTE* const)dst; |
1488 | BYTE* const oend = ostart + maxDstSize; |
1489 | blockProperties_t litbp; |
1490 | |
1491 | size_t litcSize = ZSTDv01_getcBlockSize(src, srcSize, &litbp); |
1492 | if (ZSTDv01_isError(litcSize)) return litcSize; |
1493 | if (litcSize > srcSize - ZSTD_blockHeaderSize) return ERROR(srcSize_wrong); |
1494 | ip += ZSTD_blockHeaderSize; |
1495 | |
1496 | switch(litbp.blockType) |
1497 | { |
1498 | case bt_raw: |
1499 | *litStart = ip; |
1500 | ip += litcSize; |
1501 | *litSize = litcSize; |
1502 | break; |
1503 | case bt_rle: |
1504 | { |
1505 | size_t rleSize = litbp.origSize; |
1506 | if (rleSize>maxDstSize) return ERROR(dstSize_tooSmall); |
1507 | if (!srcSize) return ERROR(srcSize_wrong); |
1508 | if (rleSize > 0) { |
1509 | memset(oend - rleSize, *ip, rleSize); |
1510 | } |
1511 | *litStart = oend - rleSize; |
1512 | *litSize = rleSize; |
1513 | ip++; |
1514 | break; |
1515 | } |
1516 | case bt_compressed: |
1517 | { |
1518 | size_t decodedLitSize = ZSTD_decompressLiterals(ctx, dst, maxDstSize, ip, litcSize); |
1519 | if (ZSTDv01_isError(decodedLitSize)) return decodedLitSize; |
1520 | *litStart = oend - decodedLitSize; |
1521 | *litSize = decodedLitSize; |
1522 | ip += litcSize; |
1523 | break; |
1524 | } |
1525 | case bt_end: |
1526 | default: |
1527 | return ERROR(GENERIC); |
1528 | } |
1529 | |
1530 | return ip-istart; |
1531 | } |
1532 | |
1533 | |
1534 | static size_t ZSTDv01_decodeSeqHeaders(int* nbSeq, const BYTE** dumpsPtr, size_t* dumpsLengthPtr, |
1535 | FSE_DTable* DTableLL, FSE_DTable* DTableML, FSE_DTable* DTableOffb, |
1536 | const void* src, size_t srcSize) |
1537 | { |
1538 | const BYTE* const istart = (const BYTE* const)src; |
1539 | const BYTE* ip = istart; |
1540 | const BYTE* const iend = istart + srcSize; |
1541 | U32 LLtype, Offtype, MLtype; |
1542 | U32 LLlog, Offlog, MLlog; |
1543 | size_t dumpsLength; |
1544 | |
1545 | /* check */ |
1546 | if (srcSize < 5) return ERROR(srcSize_wrong); |
1547 | |
1548 | /* SeqHead */ |
1549 | *nbSeq = ZSTD_readLE16(ip); ip+=2; |
1550 | LLtype = *ip >> 6; |
1551 | Offtype = (*ip >> 4) & 3; |
1552 | MLtype = (*ip >> 2) & 3; |
1553 | if (*ip & 2) |
1554 | { |
1555 | dumpsLength = ip[2]; |
1556 | dumpsLength += ip[1] << 8; |
1557 | ip += 3; |
1558 | } |
1559 | else |
1560 | { |
1561 | dumpsLength = ip[1]; |
1562 | dumpsLength += (ip[0] & 1) << 8; |
1563 | ip += 2; |
1564 | } |
1565 | *dumpsPtr = ip; |
1566 | ip += dumpsLength; |
1567 | *dumpsLengthPtr = dumpsLength; |
1568 | |
1569 | /* check */ |
1570 | if (ip > iend-3) return ERROR(srcSize_wrong); /* min : all 3 are "raw", hence no header, but at least xxLog bits per type */ |
1571 | |
1572 | /* sequences */ |
1573 | { |
1574 | S16 norm[MaxML+1]; /* assumption : MaxML >= MaxLL and MaxOff */ |
1575 | size_t headerSize; |
1576 | |
1577 | /* Build DTables */ |
1578 | switch(LLtype) |
1579 | { |
1580 | case bt_rle : |
1581 | LLlog = 0; |
1582 | FSE_buildDTable_rle(DTableLL, *ip++); break; |
1583 | case bt_raw : |
1584 | LLlog = LLbits; |
1585 | FSE_buildDTable_raw(DTableLL, LLbits); break; |
1586 | default : |
1587 | { U32 max = MaxLL; |
1588 | headerSize = FSE_readNCount(norm, &max, &LLlog, ip, iend-ip); |
1589 | if (FSE_isError(headerSize)) return ERROR(GENERIC); |
1590 | if (LLlog > LLFSELog) return ERROR(corruption_detected); |
1591 | ip += headerSize; |
1592 | FSE_buildDTable(DTableLL, norm, max, LLlog); |
1593 | } } |
1594 | |
1595 | switch(Offtype) |
1596 | { |
1597 | case bt_rle : |
1598 | Offlog = 0; |
1599 | if (ip > iend-2) return ERROR(srcSize_wrong); /* min : "raw", hence no header, but at least xxLog bits */ |
1600 | FSE_buildDTable_rle(DTableOffb, *ip++); break; |
1601 | case bt_raw : |
1602 | Offlog = Offbits; |
1603 | FSE_buildDTable_raw(DTableOffb, Offbits); break; |
1604 | default : |
1605 | { U32 max = MaxOff; |
1606 | headerSize = FSE_readNCount(norm, &max, &Offlog, ip, iend-ip); |
1607 | if (FSE_isError(headerSize)) return ERROR(GENERIC); |
1608 | if (Offlog > OffFSELog) return ERROR(corruption_detected); |
1609 | ip += headerSize; |
1610 | FSE_buildDTable(DTableOffb, norm, max, Offlog); |
1611 | } } |
1612 | |
1613 | switch(MLtype) |
1614 | { |
1615 | case bt_rle : |
1616 | MLlog = 0; |
1617 | if (ip > iend-2) return ERROR(srcSize_wrong); /* min : "raw", hence no header, but at least xxLog bits */ |
1618 | FSE_buildDTable_rle(DTableML, *ip++); break; |
1619 | case bt_raw : |
1620 | MLlog = MLbits; |
1621 | FSE_buildDTable_raw(DTableML, MLbits); break; |
1622 | default : |
1623 | { U32 max = MaxML; |
1624 | headerSize = FSE_readNCount(norm, &max, &MLlog, ip, iend-ip); |
1625 | if (FSE_isError(headerSize)) return ERROR(GENERIC); |
1626 | if (MLlog > MLFSELog) return ERROR(corruption_detected); |
1627 | ip += headerSize; |
1628 | FSE_buildDTable(DTableML, norm, max, MLlog); |
1629 | } } } |
1630 | |
1631 | return ip-istart; |
1632 | } |
1633 | |
1634 | |
1635 | typedef struct { |
1636 | size_t litLength; |
1637 | size_t offset; |
1638 | size_t matchLength; |
1639 | } seq_t; |
1640 | |
1641 | typedef struct { |
1642 | FSE_DStream_t DStream; |
1643 | FSE_DState_t stateLL; |
1644 | FSE_DState_t stateOffb; |
1645 | FSE_DState_t stateML; |
1646 | size_t prevOffset; |
1647 | const BYTE* dumps; |
1648 | const BYTE* dumpsEnd; |
1649 | } seqState_t; |
1650 | |
1651 | |
1652 | static void ZSTD_decodeSequence(seq_t* seq, seqState_t* seqState) |
1653 | { |
1654 | size_t litLength; |
1655 | size_t prevOffset; |
1656 | size_t offset; |
1657 | size_t matchLength; |
1658 | const BYTE* dumps = seqState->dumps; |
1659 | const BYTE* const de = seqState->dumpsEnd; |
1660 | |
1661 | /* Literal length */ |
1662 | litLength = FSE_decodeSymbol(&(seqState->stateLL), &(seqState->DStream)); |
1663 | prevOffset = litLength ? seq->offset : seqState->prevOffset; |
1664 | seqState->prevOffset = seq->offset; |
1665 | if (litLength == MaxLL) |
1666 | { |
1667 | const U32 add = dumps<de ? *dumps++ : 0; |
1668 | if (add < 255) litLength += add; |
1669 | else |
1670 | { |
1671 | if (dumps<=(de-3)) |
1672 | { |
1673 | litLength = ZSTD_readLE24(dumps); |
1674 | dumps += 3; |
1675 | } |
1676 | } |
1677 | } |
1678 | |
1679 | /* Offset */ |
1680 | { |
1681 | U32 offsetCode, nbBits; |
1682 | offsetCode = FSE_decodeSymbol(&(seqState->stateOffb), &(seqState->DStream)); |
1683 | if (ZSTD_32bits()) FSE_reloadDStream(&(seqState->DStream)); |
1684 | nbBits = offsetCode - 1; |
1685 | if (offsetCode==0) nbBits = 0; /* cmove */ |
1686 | offset = ((size_t)1 << (nbBits & ((sizeof(offset)*8)-1))) + FSE_readBits(&(seqState->DStream), nbBits); |
1687 | if (ZSTD_32bits()) FSE_reloadDStream(&(seqState->DStream)); |
1688 | if (offsetCode==0) offset = prevOffset; |
1689 | } |
1690 | |
1691 | /* MatchLength */ |
1692 | matchLength = FSE_decodeSymbol(&(seqState->stateML), &(seqState->DStream)); |
1693 | if (matchLength == MaxML) |
1694 | { |
1695 | const U32 add = dumps<de ? *dumps++ : 0; |
1696 | if (add < 255) matchLength += add; |
1697 | else |
1698 | { |
1699 | if (dumps<=(de-3)) |
1700 | { |
1701 | matchLength = ZSTD_readLE24(dumps); |
1702 | dumps += 3; |
1703 | } |
1704 | } |
1705 | } |
1706 | matchLength += MINMATCH; |
1707 | |
1708 | /* save result */ |
1709 | seq->litLength = litLength; |
1710 | seq->offset = offset; |
1711 | seq->matchLength = matchLength; |
1712 | seqState->dumps = dumps; |
1713 | } |
1714 | |
1715 | |
1716 | static size_t ZSTD_execSequence(BYTE* op, |
1717 | seq_t sequence, |
1718 | const BYTE** litPtr, const BYTE* const litLimit, |
1719 | BYTE* const base, BYTE* const oend) |
1720 | { |
1721 | static const int dec32table[] = {0, 1, 2, 1, 4, 4, 4, 4}; /* added */ |
1722 | static const int dec64table[] = {8, 8, 8, 7, 8, 9,10,11}; /* subtracted */ |
1723 | const BYTE* const ostart = op; |
1724 | BYTE* const oLitEnd = op + sequence.litLength; |
1725 | const size_t litLength = sequence.litLength; |
1726 | BYTE* const endMatch = op + litLength + sequence.matchLength; /* risk : address space overflow (32-bits) */ |
1727 | const BYTE* const litEnd = *litPtr + litLength; |
1728 | |
1729 | /* checks */ |
1730 | size_t const seqLength = sequence.litLength + sequence.matchLength; |
1731 | |
1732 | if (seqLength > (size_t)(oend - op)) return ERROR(dstSize_tooSmall); |
1733 | if (sequence.litLength > (size_t)(litLimit - *litPtr)) return ERROR(corruption_detected); |
1734 | /* Now we know there are no overflow in literal nor match lengths, can use pointer checks */ |
1735 | if (sequence.offset > (U32)(oLitEnd - base)) return ERROR(corruption_detected); |
1736 | |
1737 | if (endMatch > oend) return ERROR(dstSize_tooSmall); /* overwrite beyond dst buffer */ |
1738 | if (litEnd > litLimit) return ERROR(corruption_detected); /* overRead beyond lit buffer */ |
1739 | if (sequence.matchLength > (size_t)(*litPtr-op)) return ERROR(dstSize_tooSmall); /* overwrite literal segment */ |
1740 | |
1741 | /* copy Literals */ |
1742 | ZSTD_memmove(op, *litPtr, sequence.litLength); /* note : v0.1 seems to allow scenarios where output or input are close to end of buffer */ |
1743 | |
1744 | op += litLength; |
1745 | *litPtr = litEnd; /* update for next sequence */ |
1746 | |
1747 | /* check : last match must be at a minimum distance of 8 from end of dest buffer */ |
1748 | if (oend-op < 8) return ERROR(dstSize_tooSmall); |
1749 | |
1750 | /* copy Match */ |
1751 | { |
1752 | const U32 overlapRisk = (((size_t)(litEnd - endMatch)) < 12); |
1753 | const BYTE* match = op - sequence.offset; /* possible underflow at op - offset ? */ |
1754 | size_t qutt = 12; |
1755 | U64 saved[2]; |
1756 | |
1757 | /* check */ |
1758 | if (match < base) return ERROR(corruption_detected); |
1759 | if (sequence.offset > (size_t)base) return ERROR(corruption_detected); |
1760 | |
1761 | /* save beginning of literal sequence, in case of write overlap */ |
1762 | if (overlapRisk) |
1763 | { |
1764 | if ((endMatch + qutt) > oend) qutt = oend-endMatch; |
1765 | memcpy(saved, endMatch, qutt); |
1766 | } |
1767 | |
1768 | if (sequence.offset < 8) |
1769 | { |
1770 | const int dec64 = dec64table[sequence.offset]; |
1771 | op[0] = match[0]; |
1772 | op[1] = match[1]; |
1773 | op[2] = match[2]; |
1774 | op[3] = match[3]; |
1775 | match += dec32table[sequence.offset]; |
1776 | ZSTD_copy4(op+4, match); |
1777 | match -= dec64; |
1778 | } else { ZSTD_copy8(op, match); } |
1779 | op += 8; match += 8; |
1780 | |
1781 | if (endMatch > oend-(16-MINMATCH)) |
1782 | { |
1783 | if (op < oend-8) |
1784 | { |
1785 | ZSTD_wildcopy(op, match, (oend-8) - op); |
1786 | match += (oend-8) - op; |
1787 | op = oend-8; |
1788 | } |
1789 | while (op<endMatch) *op++ = *match++; |
1790 | } |
1791 | else |
1792 | ZSTD_wildcopy(op, match, (ptrdiff_t)sequence.matchLength-8); /* works even if matchLength < 8 */ |
1793 | |
1794 | /* restore, in case of overlap */ |
1795 | if (overlapRisk) memcpy(endMatch, saved, qutt); |
1796 | } |
1797 | |
1798 | return endMatch-ostart; |
1799 | } |
1800 | |
1801 | typedef struct ZSTDv01_Dctx_s |
1802 | { |
1803 | U32 LLTable[FSE_DTABLE_SIZE_U32(LLFSELog)]; |
1804 | U32 OffTable[FSE_DTABLE_SIZE_U32(OffFSELog)]; |
1805 | U32 MLTable[FSE_DTABLE_SIZE_U32(MLFSELog)]; |
1806 | void* previousDstEnd; |
1807 | void* base; |
1808 | size_t expected; |
1809 | blockType_t bType; |
1810 | U32 phase; |
1811 | } dctx_t; |
1812 | |
1813 | |
1814 | static size_t ZSTD_decompressSequences( |
1815 | void* ctx, |
1816 | void* dst, size_t maxDstSize, |
1817 | const void* seqStart, size_t seqSize, |
1818 | const BYTE* litStart, size_t litSize) |
1819 | { |
1820 | dctx_t* dctx = (dctx_t*)ctx; |
1821 | const BYTE* ip = (const BYTE*)seqStart; |
1822 | const BYTE* const iend = ip + seqSize; |
1823 | BYTE* const ostart = (BYTE* const)dst; |
1824 | BYTE* op = ostart; |
1825 | BYTE* const oend = ostart + maxDstSize; |
1826 | size_t errorCode, dumpsLength; |
1827 | const BYTE* litPtr = litStart; |
1828 | const BYTE* const litEnd = litStart + litSize; |
1829 | int nbSeq; |
1830 | const BYTE* dumps; |
1831 | U32* DTableLL = dctx->LLTable; |
1832 | U32* DTableML = dctx->MLTable; |
1833 | U32* DTableOffb = dctx->OffTable; |
1834 | BYTE* const base = (BYTE*) (dctx->base); |
1835 | |
1836 | /* Build Decoding Tables */ |
1837 | errorCode = ZSTDv01_decodeSeqHeaders(&nbSeq, &dumps, &dumpsLength, |
1838 | DTableLL, DTableML, DTableOffb, |
1839 | ip, iend-ip); |
1840 | if (ZSTDv01_isError(errorCode)) return errorCode; |
1841 | ip += errorCode; |
1842 | |
1843 | /* Regen sequences */ |
1844 | { |
1845 | seq_t sequence; |
1846 | seqState_t seqState; |
1847 | |
1848 | memset(&sequence, 0, sizeof(sequence)); |
1849 | seqState.dumps = dumps; |
1850 | seqState.dumpsEnd = dumps + dumpsLength; |
1851 | seqState.prevOffset = 1; |
1852 | errorCode = FSE_initDStream(&(seqState.DStream), ip, iend-ip); |
1853 | if (FSE_isError(errorCode)) return ERROR(corruption_detected); |
1854 | FSE_initDState(&(seqState.stateLL), &(seqState.DStream), DTableLL); |
1855 | FSE_initDState(&(seqState.stateOffb), &(seqState.DStream), DTableOffb); |
1856 | FSE_initDState(&(seqState.stateML), &(seqState.DStream), DTableML); |
1857 | |
1858 | for ( ; (FSE_reloadDStream(&(seqState.DStream)) <= FSE_DStream_completed) && (nbSeq>0) ; ) |
1859 | { |
1860 | size_t oneSeqSize; |
1861 | nbSeq--; |
1862 | ZSTD_decodeSequence(&sequence, &seqState); |
1863 | oneSeqSize = ZSTD_execSequence(op, sequence, &litPtr, litEnd, base, oend); |
1864 | if (ZSTDv01_isError(oneSeqSize)) return oneSeqSize; |
1865 | op += oneSeqSize; |
1866 | } |
1867 | |
1868 | /* check if reached exact end */ |
1869 | if ( !FSE_endOfDStream(&(seqState.DStream)) ) return ERROR(corruption_detected); /* requested too much : data is corrupted */ |
1870 | if (nbSeq<0) return ERROR(corruption_detected); /* requested too many sequences : data is corrupted */ |
1871 | |
1872 | /* last literal segment */ |
1873 | { |
1874 | size_t lastLLSize = litEnd - litPtr; |
1875 | if (op+lastLLSize > oend) return ERROR(dstSize_tooSmall); |
1876 | if (lastLLSize > 0) { |
1877 | if (op != litPtr) memmove(op, litPtr, lastLLSize); |
1878 | op += lastLLSize; |
1879 | } |
1880 | } |
1881 | } |
1882 | |
1883 | return op-ostart; |
1884 | } |
1885 | |
1886 | |
1887 | static size_t ZSTD_decompressBlock( |
1888 | void* ctx, |
1889 | void* dst, size_t maxDstSize, |
1890 | const void* src, size_t srcSize) |
1891 | { |
1892 | /* blockType == blockCompressed, srcSize is trusted */ |
1893 | const BYTE* ip = (const BYTE*)src; |
1894 | const BYTE* litPtr = NULL; |
1895 | size_t litSize = 0; |
1896 | size_t errorCode; |
1897 | |
1898 | /* Decode literals sub-block */ |
1899 | errorCode = ZSTDv01_decodeLiteralsBlock(ctx, dst, maxDstSize, &litPtr, &litSize, src, srcSize); |
1900 | if (ZSTDv01_isError(errorCode)) return errorCode; |
1901 | ip += errorCode; |
1902 | srcSize -= errorCode; |
1903 | |
1904 | return ZSTD_decompressSequences(ctx, dst, maxDstSize, ip, srcSize, litPtr, litSize); |
1905 | } |
1906 | |
1907 | |
1908 | size_t ZSTDv01_decompressDCtx(void* ctx, void* dst, size_t maxDstSize, const void* src, size_t srcSize) |
1909 | { |
1910 | const BYTE* ip = (const BYTE*)src; |
1911 | const BYTE* iend = ip + srcSize; |
1912 | BYTE* const ostart = (BYTE* const)dst; |
1913 | BYTE* op = ostart; |
1914 | BYTE* const oend = ostart + maxDstSize; |
1915 | size_t remainingSize = srcSize; |
1916 | U32 magicNumber; |
1917 | size_t errorCode=0; |
1918 | blockProperties_t blockProperties; |
1919 | |
1920 | /* Frame Header */ |
1921 | if (srcSize < ZSTD_frameHeaderSize+ZSTD_blockHeaderSize) return ERROR(srcSize_wrong); |
1922 | magicNumber = ZSTD_readBE32(src); |
1923 | if (magicNumber != ZSTD_magicNumber) return ERROR(prefix_unknown); |
1924 | ip += ZSTD_frameHeaderSize; remainingSize -= ZSTD_frameHeaderSize; |
1925 | |
1926 | /* Loop on each block */ |
1927 | while (1) |
1928 | { |
1929 | size_t blockSize = ZSTDv01_getcBlockSize(ip, iend-ip, &blockProperties); |
1930 | if (ZSTDv01_isError(blockSize)) return blockSize; |
1931 | |
1932 | ip += ZSTD_blockHeaderSize; |
1933 | remainingSize -= ZSTD_blockHeaderSize; |
1934 | if (blockSize > remainingSize) return ERROR(srcSize_wrong); |
1935 | |
1936 | switch(blockProperties.blockType) |
1937 | { |
1938 | case bt_compressed: |
1939 | errorCode = ZSTD_decompressBlock(ctx, op, oend-op, ip, blockSize); |
1940 | break; |
1941 | case bt_raw : |
1942 | errorCode = ZSTD_copyUncompressedBlock(op, oend-op, ip, blockSize); |
1943 | break; |
1944 | case bt_rle : |
1945 | return ERROR(GENERIC); /* not yet supported */ |
1946 | break; |
1947 | case bt_end : |
1948 | /* end of frame */ |
1949 | if (remainingSize) return ERROR(srcSize_wrong); |
1950 | break; |
1951 | default: |
1952 | return ERROR(GENERIC); |
1953 | } |
1954 | if (blockSize == 0) break; /* bt_end */ |
1955 | |
1956 | if (ZSTDv01_isError(errorCode)) return errorCode; |
1957 | op += errorCode; |
1958 | ip += blockSize; |
1959 | remainingSize -= blockSize; |
1960 | } |
1961 | |
1962 | return op-ostart; |
1963 | } |
1964 | |
1965 | size_t ZSTDv01_decompress(void* dst, size_t maxDstSize, const void* src, size_t srcSize) |
1966 | { |
1967 | dctx_t ctx; |
1968 | ctx.base = dst; |
1969 | return ZSTDv01_decompressDCtx(&ctx, dst, maxDstSize, src, srcSize); |
1970 | } |
1971 | |
1972 | /* ZSTD_errorFrameSizeInfoLegacy() : |
1973 | assumes `cSize` and `dBound` are _not_ NULL */ |
1974 | static void ZSTD_errorFrameSizeInfoLegacy(size_t* cSize, unsigned long long* dBound, size_t ret) |
1975 | { |
1976 | *cSize = ret; |
1977 | *dBound = ZSTD_CONTENTSIZE_ERROR; |
1978 | } |
1979 | |
1980 | void ZSTDv01_findFrameSizeInfoLegacy(const void *src, size_t srcSize, size_t* cSize, unsigned long long* dBound) |
1981 | { |
1982 | const BYTE* ip = (const BYTE*)src; |
1983 | size_t remainingSize = srcSize; |
1984 | size_t nbBlocks = 0; |
1985 | U32 magicNumber; |
1986 | blockProperties_t blockProperties; |
1987 | |
1988 | /* Frame Header */ |
1989 | if (srcSize < ZSTD_frameHeaderSize+ZSTD_blockHeaderSize) { |
1990 | ZSTD_errorFrameSizeInfoLegacy(cSize, dBound, ERROR(srcSize_wrong)); |
1991 | return; |
1992 | } |
1993 | magicNumber = ZSTD_readBE32(src); |
1994 | if (magicNumber != ZSTD_magicNumber) { |
1995 | ZSTD_errorFrameSizeInfoLegacy(cSize, dBound, ERROR(prefix_unknown)); |
1996 | return; |
1997 | } |
1998 | ip += ZSTD_frameHeaderSize; remainingSize -= ZSTD_frameHeaderSize; |
1999 | |
2000 | /* Loop on each block */ |
2001 | while (1) |
2002 | { |
2003 | size_t blockSize = ZSTDv01_getcBlockSize(ip, remainingSize, &blockProperties); |
2004 | if (ZSTDv01_isError(blockSize)) { |
2005 | ZSTD_errorFrameSizeInfoLegacy(cSize, dBound, blockSize); |
2006 | return; |
2007 | } |
2008 | |
2009 | ip += ZSTD_blockHeaderSize; |
2010 | remainingSize -= ZSTD_blockHeaderSize; |
2011 | if (blockSize > remainingSize) { |
2012 | ZSTD_errorFrameSizeInfoLegacy(cSize, dBound, ERROR(srcSize_wrong)); |
2013 | return; |
2014 | } |
2015 | |
2016 | if (blockSize == 0) break; /* bt_end */ |
2017 | |
2018 | ip += blockSize; |
2019 | remainingSize -= blockSize; |
2020 | nbBlocks++; |
2021 | } |
2022 | |
2023 | *cSize = ip - (const BYTE*)src; |
2024 | *dBound = nbBlocks * BLOCKSIZE; |
2025 | } |
2026 | |
2027 | /******************************* |
2028 | * Streaming Decompression API |
2029 | *******************************/ |
2030 | |
2031 | size_t ZSTDv01_resetDCtx(ZSTDv01_Dctx* dctx) |
2032 | { |
2033 | dctx->expected = ZSTD_frameHeaderSize; |
2034 | dctx->phase = 0; |
2035 | dctx->previousDstEnd = NULL; |
2036 | dctx->base = NULL; |
2037 | return 0; |
2038 | } |
2039 | |
2040 | ZSTDv01_Dctx* ZSTDv01_createDCtx(void) |
2041 | { |
2042 | ZSTDv01_Dctx* dctx = (ZSTDv01_Dctx*)malloc(sizeof(ZSTDv01_Dctx)); |
2043 | if (dctx==NULL) return NULL; |
2044 | ZSTDv01_resetDCtx(dctx); |
2045 | return dctx; |
2046 | } |
2047 | |
2048 | size_t ZSTDv01_freeDCtx(ZSTDv01_Dctx* dctx) |
2049 | { |
2050 | free(dctx); |
2051 | return 0; |
2052 | } |
2053 | |
2054 | size_t ZSTDv01_nextSrcSizeToDecompress(ZSTDv01_Dctx* dctx) |
2055 | { |
2056 | return ((dctx_t*)dctx)->expected; |
2057 | } |
2058 | |
2059 | size_t ZSTDv01_decompressContinue(ZSTDv01_Dctx* dctx, void* dst, size_t maxDstSize, const void* src, size_t srcSize) |
2060 | { |
2061 | dctx_t* ctx = (dctx_t*)dctx; |
2062 | |
2063 | /* Sanity check */ |
2064 | if (srcSize != ctx->expected) return ERROR(srcSize_wrong); |
2065 | if (dst != ctx->previousDstEnd) /* not contiguous */ |
2066 | ctx->base = dst; |
2067 | |
2068 | /* Decompress : frame header */ |
2069 | if (ctx->phase == 0) |
2070 | { |
2071 | /* Check frame magic header */ |
2072 | U32 magicNumber = ZSTD_readBE32(src); |
2073 | if (magicNumber != ZSTD_magicNumber) return ERROR(prefix_unknown); |
2074 | ctx->phase = 1; |
2075 | ctx->expected = ZSTD_blockHeaderSize; |
2076 | return 0; |
2077 | } |
2078 | |
2079 | /* Decompress : block header */ |
2080 | if (ctx->phase == 1) |
2081 | { |
2082 | blockProperties_t bp; |
2083 | size_t blockSize = ZSTDv01_getcBlockSize(src, ZSTD_blockHeaderSize, &bp); |
2084 | if (ZSTDv01_isError(blockSize)) return blockSize; |
2085 | if (bp.blockType == bt_end) |
2086 | { |
2087 | ctx->expected = 0; |
2088 | ctx->phase = 0; |
2089 | } |
2090 | else |
2091 | { |
2092 | ctx->expected = blockSize; |
2093 | ctx->bType = bp.blockType; |
2094 | ctx->phase = 2; |
2095 | } |
2096 | |
2097 | return 0; |
2098 | } |
2099 | |
2100 | /* Decompress : block content */ |
2101 | { |
2102 | size_t rSize; |
2103 | switch(ctx->bType) |
2104 | { |
2105 | case bt_compressed: |
2106 | rSize = ZSTD_decompressBlock(ctx, dst, maxDstSize, src, srcSize); |
2107 | break; |
2108 | case bt_raw : |
2109 | rSize = ZSTD_copyUncompressedBlock(dst, maxDstSize, src, srcSize); |
2110 | break; |
2111 | case bt_rle : |
2112 | return ERROR(GENERIC); /* not yet handled */ |
2113 | break; |
2114 | case bt_end : /* should never happen (filtered at phase 1) */ |
2115 | rSize = 0; |
2116 | break; |
2117 | default: |
2118 | return ERROR(GENERIC); |
2119 | } |
2120 | ctx->phase = 1; |
2121 | ctx->expected = ZSTD_blockHeaderSize; |
f535537f |
2122 | if (ZSTDv01_isError(rSize)) return rSize; |
648db22b |
2123 | ctx->previousDstEnd = (void*)( ((char*)dst) + rSize); |
2124 | return rSize; |
2125 | } |
2126 | |
2127 | } |