1 /*
2 * Copyright (c) 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 #ifndef ZSTD_CCOMMON_H_MODULE
12 #define ZSTD_CCOMMON_H_MODULE
13
14 /* this module contains definitions which must be identical
15 * across compression, decompression and dictBuilder.
16 * It also contains a few functions useful to at least 2 of them
17 * and which benefit from being inlined */
18
19 /*-*************************************
20 * Dependencies
21 ***************************************/
22 #include "compiler.h"
23 #include "mem.h"
24 #include "debug.h" /* assert, DEBUGLOG, RAWLOG, g_debuglevel */
25 #include "error_private.h"
26 #define ZSTD_STATIC_LINKING_ONLY
27 #include <linux/zstd.h>
28 #define FSE_STATIC_LINKING_ONLY
29 #include "fse.h"
30 #define HUF_STATIC_LINKING_ONLY
31 #include "huf.h"
32 #include <linux/xxhash.h> /* XXH_reset, update, digest */
33 #define ZSTD_TRACE 0
34
35
36 /* ---- static assert (debug) --- */
37 #define ZSTD_STATIC_ASSERT(c) DEBUG_STATIC_ASSERT(c)
38 #define ZSTD_isError ERR_isError /* for inlining */
39 #define FSE_isError ERR_isError
40 #define HUF_isError ERR_isError
41
42
43 /*-*************************************
44 * shared macros
45 ***************************************/
46 #undef MIN
47 #undef MAX
48 #define MIN(a,b) ((a)<(b) ? (a) : (b))
49 #define MAX(a,b) ((a)>(b) ? (a) : (b))
50
51 /*
52 * Ignore: this is an internal helper.
53 *
54 * This is a helper function to help force C99-correctness during compilation.
55 * Under strict compilation modes, variadic macro arguments can't be empty.
56 * However, variadic function arguments can be. Using a function therefore lets
57 * us statically check that at least one (string) argument was passed,
58 * independent of the compilation flags.
59 */
60 static INLINE_KEYWORD UNUSED_ATTR
_force_has_format_string(const char * format,...)61 void _force_has_format_string(const char *format, ...) {
62 (void)format;
63 }
64
65 /*
66 * Ignore: this is an internal helper.
67 *
68 * We want to force this function invocation to be syntactically correct, but
69 * we don't want to force runtime evaluation of its arguments.
70 */
71 #define _FORCE_HAS_FORMAT_STRING(...) \
72 if (0) { \
73 _force_has_format_string(__VA_ARGS__); \
74 }
75
76 /*
77 * Return the specified error if the condition evaluates to true.
78 *
79 * In debug modes, prints additional information.
80 * In order to do that (particularly, printing the conditional that failed),
81 * this can't just wrap RETURN_ERROR().
82 */
83 #define RETURN_ERROR_IF(cond, err, ...) \
84 if (cond) { \
85 RAWLOG(3, "%s:%d: ERROR!: check %s failed, returning %s", \
86 __FILE__, __LINE__, ZSTD_QUOTE(cond), ZSTD_QUOTE(ERROR(err))); \
87 _FORCE_HAS_FORMAT_STRING(__VA_ARGS__); \
88 RAWLOG(3, ": " __VA_ARGS__); \
89 RAWLOG(3, "\n"); \
90 return ERROR(err); \
91 }
92
93 /*
94 * Unconditionally return the specified error.
95 *
96 * In debug modes, prints additional information.
97 */
98 #define RETURN_ERROR(err, ...) \
99 do { \
100 RAWLOG(3, "%s:%d: ERROR!: unconditional check failed, returning %s", \
101 __FILE__, __LINE__, ZSTD_QUOTE(ERROR(err))); \
102 _FORCE_HAS_FORMAT_STRING(__VA_ARGS__); \
103 RAWLOG(3, ": " __VA_ARGS__); \
104 RAWLOG(3, "\n"); \
105 return ERROR(err); \
106 } while(0);
107
108 /*
109 * If the provided expression evaluates to an error code, returns that error code.
110 *
111 * In debug modes, prints additional information.
112 */
113 #define FORWARD_IF_ERROR(err, ...) \
114 do { \
115 size_t const err_code = (err); \
116 if (ERR_isError(err_code)) { \
117 RAWLOG(3, "%s:%d: ERROR!: forwarding error in %s: %s", \
118 __FILE__, __LINE__, ZSTD_QUOTE(err), ERR_getErrorName(err_code)); \
119 _FORCE_HAS_FORMAT_STRING(__VA_ARGS__); \
120 RAWLOG(3, ": " __VA_ARGS__); \
121 RAWLOG(3, "\n"); \
122 return err_code; \
123 } \
124 } while(0);
125
126
127 /*-*************************************
128 * Common constants
129 ***************************************/
130 #define ZSTD_OPT_NUM (1<<12)
131
132 #define ZSTD_REP_NUM 3 /* number of repcodes */
133 #define ZSTD_REP_MOVE (ZSTD_REP_NUM-1)
134 static UNUSED_ATTR const U32 repStartValue[ZSTD_REP_NUM] = { 1, 4, 8 };
135
136 #define KB *(1 <<10)
137 #define MB *(1 <<20)
138 #define GB *(1U<<30)
139
140 #define BIT7 128
141 #define BIT6 64
142 #define BIT5 32
143 #define BIT4 16
144 #define BIT1 2
145 #define BIT0 1
146
147 #define ZSTD_WINDOWLOG_ABSOLUTEMIN 10
148 static UNUSED_ATTR const size_t ZSTD_fcs_fieldSize[4] = { 0, 2, 4, 8 };
149 static UNUSED_ATTR const size_t ZSTD_did_fieldSize[4] = { 0, 1, 2, 4 };
150
151 #define ZSTD_FRAMEIDSIZE 4 /* magic number size */
152
153 #define ZSTD_BLOCKHEADERSIZE 3 /* C standard doesn't allow `static const` variable to be init using another `static const` variable */
154 static UNUSED_ATTR const size_t ZSTD_blockHeaderSize = ZSTD_BLOCKHEADERSIZE;
155 typedef enum { bt_raw, bt_rle, bt_compressed, bt_reserved } blockType_e;
156
157 #define ZSTD_FRAMECHECKSUMSIZE 4
158
159 #define MIN_SEQUENCES_SIZE 1 /* nbSeq==0 */
160 #define MIN_CBLOCK_SIZE (1 /*litCSize*/ + 1 /* RLE or RAW */ + MIN_SEQUENCES_SIZE /* nbSeq==0 */) /* for a non-null block */
161
162 #define HufLog 12
163 typedef enum { set_basic, set_rle, set_compressed, set_repeat } symbolEncodingType_e;
164
165 #define LONGNBSEQ 0x7F00
166
167 #define MINMATCH 3
168
169 #define Litbits 8
170 #define MaxLit ((1<<Litbits) - 1)
171 #define MaxML 52
172 #define MaxLL 35
173 #define DefaultMaxOff 28
174 #define MaxOff 31
175 #define MaxSeq MAX(MaxLL, MaxML) /* Assumption : MaxOff < MaxLL,MaxML */
176 #define MLFSELog 9
177 #define LLFSELog 9
178 #define OffFSELog 8
179 #define MaxFSELog MAX(MAX(MLFSELog, LLFSELog), OffFSELog)
180
181 #define ZSTD_MAX_HUF_HEADER_SIZE 128 /* header + <= 127 byte tree description */
182 /* Each table cannot take more than #symbols * FSELog bits */
183 #define ZSTD_MAX_FSE_HEADERS_SIZE (((MaxML + 1) * MLFSELog + (MaxLL + 1) * LLFSELog + (MaxOff + 1) * OffFSELog + 7) / 8)
184
185 static UNUSED_ATTR const U32 LL_bits[MaxLL+1] = {
186 0, 0, 0, 0, 0, 0, 0, 0,
187 0, 0, 0, 0, 0, 0, 0, 0,
188 1, 1, 1, 1, 2, 2, 3, 3,
189 4, 6, 7, 8, 9,10,11,12,
190 13,14,15,16
191 };
192 static UNUSED_ATTR const S16 LL_defaultNorm[MaxLL+1] = {
193 4, 3, 2, 2, 2, 2, 2, 2,
194 2, 2, 2, 2, 2, 1, 1, 1,
195 2, 2, 2, 2, 2, 2, 2, 2,
196 2, 3, 2, 1, 1, 1, 1, 1,
197 -1,-1,-1,-1
198 };
199 #define LL_DEFAULTNORMLOG 6 /* for static allocation */
200 static UNUSED_ATTR const U32 LL_defaultNormLog = LL_DEFAULTNORMLOG;
201
202 static UNUSED_ATTR const U32 ML_bits[MaxML+1] = {
203 0, 0, 0, 0, 0, 0, 0, 0,
204 0, 0, 0, 0, 0, 0, 0, 0,
205 0, 0, 0, 0, 0, 0, 0, 0,
206 0, 0, 0, 0, 0, 0, 0, 0,
207 1, 1, 1, 1, 2, 2, 3, 3,
208 4, 4, 5, 7, 8, 9,10,11,
209 12,13,14,15,16
210 };
211 static UNUSED_ATTR const S16 ML_defaultNorm[MaxML+1] = {
212 1, 4, 3, 2, 2, 2, 2, 2,
213 2, 1, 1, 1, 1, 1, 1, 1,
214 1, 1, 1, 1, 1, 1, 1, 1,
215 1, 1, 1, 1, 1, 1, 1, 1,
216 1, 1, 1, 1, 1, 1, 1, 1,
217 1, 1, 1, 1, 1, 1,-1,-1,
218 -1,-1,-1,-1,-1
219 };
220 #define ML_DEFAULTNORMLOG 6 /* for static allocation */
221 static UNUSED_ATTR const U32 ML_defaultNormLog = ML_DEFAULTNORMLOG;
222
223 static UNUSED_ATTR const S16 OF_defaultNorm[DefaultMaxOff+1] = {
224 1, 1, 1, 1, 1, 1, 2, 2,
225 2, 1, 1, 1, 1, 1, 1, 1,
226 1, 1, 1, 1, 1, 1, 1, 1,
227 -1,-1,-1,-1,-1
228 };
229 #define OF_DEFAULTNORMLOG 5 /* for static allocation */
230 static UNUSED_ATTR const U32 OF_defaultNormLog = OF_DEFAULTNORMLOG;
231
232
233 /*-*******************************************
234 * Shared functions to include for inlining
235 *********************************************/
ZSTD_copy8(void * dst,const void * src)236 static void ZSTD_copy8(void* dst, const void* src) {
237 ZSTD_memcpy(dst, src, 8);
238 }
239
240 #define COPY8(d,s) { ZSTD_copy8(d,s); d+=8; s+=8; }
ZSTD_copy16(void * dst,const void * src)241 static void ZSTD_copy16(void* dst, const void* src) {
242 ZSTD_memcpy(dst, src, 16);
243 }
244 #define COPY16(d,s) { ZSTD_copy16(d,s); d+=16; s+=16; }
245
246 #define WILDCOPY_OVERLENGTH 32
247 #define WILDCOPY_VECLEN 16
248
249 typedef enum {
250 ZSTD_no_overlap,
251 ZSTD_overlap_src_before_dst
252 /* ZSTD_overlap_dst_before_src, */
253 } ZSTD_overlap_e;
254
255 /*! ZSTD_wildcopy() :
256 * Custom version of ZSTD_memcpy(), can over read/write up to WILDCOPY_OVERLENGTH bytes (if length==0)
257 * @param ovtype controls the overlap detection
258 * - ZSTD_no_overlap: The source and destination are guaranteed to be at least WILDCOPY_VECLEN bytes apart.
259 * - ZSTD_overlap_src_before_dst: The src and dst may overlap, but they MUST be at least 8 bytes apart.
260 * The src buffer must be before the dst buffer.
261 */
262 MEM_STATIC FORCE_INLINE_ATTR
ZSTD_wildcopy(void * dst,const void * src,ptrdiff_t length,ZSTD_overlap_e const ovtype)263 void ZSTD_wildcopy(void* dst, const void* src, ptrdiff_t length, ZSTD_overlap_e const ovtype)
264 {
265 ptrdiff_t diff = (BYTE*)dst - (const BYTE*)src;
266 const BYTE* ip = (const BYTE*)src;
267 BYTE* op = (BYTE*)dst;
268 BYTE* const oend = op + length;
269
270 assert(diff >= 8 || (ovtype == ZSTD_no_overlap && diff <= -WILDCOPY_VECLEN));
271
272 if (ovtype == ZSTD_overlap_src_before_dst && diff < WILDCOPY_VECLEN) {
273 /* Handle short offset copies. */
274 do {
275 COPY8(op, ip)
276 } while (op < oend);
277 } else {
278 assert(diff >= WILDCOPY_VECLEN || diff <= -WILDCOPY_VECLEN);
279 /* Separate out the first COPY16() call because the copy length is
280 * almost certain to be short, so the branches have different
281 * probabilities. Since it is almost certain to be short, only do
282 * one COPY16() in the first call. Then, do two calls per loop since
283 * at that point it is more likely to have a high trip count.
284 */
285 #ifdef __aarch64__
286 do {
287 COPY16(op, ip);
288 }
289 while (op < oend);
290 #else
291 ZSTD_copy16(op, ip);
292 if (16 >= length) return;
293 op += 16;
294 ip += 16;
295 do {
296 COPY16(op, ip);
297 COPY16(op, ip);
298 }
299 while (op < oend);
300 #endif
301 }
302 }
303
ZSTD_limitCopy(void * dst,size_t dstCapacity,const void * src,size_t srcSize)304 MEM_STATIC size_t ZSTD_limitCopy(void* dst, size_t dstCapacity, const void* src, size_t srcSize)
305 {
306 size_t const length = MIN(dstCapacity, srcSize);
307 if (length > 0) {
308 ZSTD_memcpy(dst, src, length);
309 }
310 return length;
311 }
312
313 /* define "workspace is too large" as this number of times larger than needed */
314 #define ZSTD_WORKSPACETOOLARGE_FACTOR 3
315
316 /* when workspace is continuously too large
317 * during at least this number of times,
318 * context's memory usage is considered wasteful,
319 * because it's sized to handle a worst case scenario which rarely happens.
320 * In which case, resize it down to free some memory */
321 #define ZSTD_WORKSPACETOOLARGE_MAXDURATION 128
322
323 /* Controls whether the input/output buffer is buffered or stable. */
324 typedef enum {
325 ZSTD_bm_buffered = 0, /* Buffer the input/output */
326 ZSTD_bm_stable = 1 /* ZSTD_inBuffer/ZSTD_outBuffer is stable */
327 } ZSTD_bufferMode_e;
328
329
330 /*-*******************************************
331 * Private declarations
332 *********************************************/
333 typedef struct seqDef_s {
334 U32 offset; /* Offset code of the sequence */
335 U16 litLength;
336 U16 matchLength;
337 } seqDef;
338
339 typedef struct {
340 seqDef* sequencesStart;
341 seqDef* sequences; /* ptr to end of sequences */
342 BYTE* litStart;
343 BYTE* lit; /* ptr to end of literals */
344 BYTE* llCode;
345 BYTE* mlCode;
346 BYTE* ofCode;
347 size_t maxNbSeq;
348 size_t maxNbLit;
349
350 /* longLengthPos and longLengthID to allow us to represent either a single litLength or matchLength
351 * in the seqStore that has a value larger than U16 (if it exists). To do so, we increment
352 * the existing value of the litLength or matchLength by 0x10000.
353 */
354 U32 longLengthID; /* 0 == no longLength; 1 == Represent the long literal; 2 == Represent the long match; */
355 U32 longLengthPos; /* Index of the sequence to apply long length modification to */
356 } seqStore_t;
357
358 typedef struct {
359 U32 litLength;
360 U32 matchLength;
361 } ZSTD_sequenceLength;
362
363 /*
364 * Returns the ZSTD_sequenceLength for the given sequences. It handles the decoding of long sequences
365 * indicated by longLengthPos and longLengthID, and adds MINMATCH back to matchLength.
366 */
ZSTD_getSequenceLength(seqStore_t const * seqStore,seqDef const * seq)367 MEM_STATIC ZSTD_sequenceLength ZSTD_getSequenceLength(seqStore_t const* seqStore, seqDef const* seq)
368 {
369 ZSTD_sequenceLength seqLen;
370 seqLen.litLength = seq->litLength;
371 seqLen.matchLength = seq->matchLength + MINMATCH;
372 if (seqStore->longLengthPos == (U32)(seq - seqStore->sequencesStart)) {
373 if (seqStore->longLengthID == 1) {
374 seqLen.litLength += 0xFFFF;
375 }
376 if (seqStore->longLengthID == 2) {
377 seqLen.matchLength += 0xFFFF;
378 }
379 }
380 return seqLen;
381 }
382
383 /*
384 * Contains the compressed frame size and an upper-bound for the decompressed frame size.
385 * Note: before using `compressedSize`, check for errors using ZSTD_isError().
386 * similarly, before using `decompressedBound`, check for errors using:
387 * `decompressedBound != ZSTD_CONTENTSIZE_ERROR`
388 */
389 typedef struct {
390 size_t compressedSize;
391 unsigned long long decompressedBound;
392 } ZSTD_frameSizeInfo; /* decompress & legacy */
393
394 const seqStore_t* ZSTD_getSeqStore(const ZSTD_CCtx* ctx); /* compress & dictBuilder */
395 void ZSTD_seqToCodes(const seqStore_t* seqStorePtr); /* compress, dictBuilder, decodeCorpus (shouldn't get its definition from here) */
396
397 /* custom memory allocation functions */
398 void* ZSTD_customMalloc(size_t size, ZSTD_customMem customMem);
399 void* ZSTD_customCalloc(size_t size, ZSTD_customMem customMem);
400 void ZSTD_customFree(void* ptr, ZSTD_customMem customMem);
401
402
ZSTD_highbit32(U32 val)403 MEM_STATIC U32 ZSTD_highbit32(U32 val) /* compress, dictBuilder, decodeCorpus */
404 {
405 assert(val != 0);
406 {
407 # if (__GNUC__ >= 3) /* GCC Intrinsic */
408 return __builtin_clz (val) ^ 31;
409 # else /* Software version */
410 static const U32 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 };
411 U32 v = val;
412 v |= v >> 1;
413 v |= v >> 2;
414 v |= v >> 4;
415 v |= v >> 8;
416 v |= v >> 16;
417 return DeBruijnClz[(v * 0x07C4ACDDU) >> 27];
418 # endif
419 }
420 }
421
422
423 /* ZSTD_invalidateRepCodes() :
424 * ensures next compression will not use repcodes from previous block.
425 * Note : only works with regular variant;
426 * do not use with extDict variant ! */
427 void ZSTD_invalidateRepCodes(ZSTD_CCtx* cctx); /* zstdmt, adaptive_compression (shouldn't get this definition from here) */
428
429
430 typedef struct {
431 blockType_e blockType;
432 U32 lastBlock;
433 U32 origSize;
434 } blockProperties_t; /* declared here for decompress and fullbench */
435
436 /*! ZSTD_getcBlockSize() :
437 * Provides the size of compressed block from block header `src` */
438 /* Used by: decompress, fullbench (does not get its definition from here) */
439 size_t ZSTD_getcBlockSize(const void* src, size_t srcSize,
440 blockProperties_t* bpPtr);
441
442 /*! ZSTD_decodeSeqHeaders() :
443 * decode sequence header from src */
444 /* Used by: decompress, fullbench (does not get its definition from here) */
445 size_t ZSTD_decodeSeqHeaders(ZSTD_DCtx* dctx, int* nbSeqPtr,
446 const void* src, size_t srcSize);
447
448
449
450 #endif /* ZSTD_CCOMMON_H_MODULE */
451