xref: /freebsd/sys/contrib/zstd/lib/common/zstd_internal.h (revision 62cfcf62f627e5093fb37026a6d8c98e4d2ef04c)
1 /*
2  * Copyright (c) 2016-2020, Yann Collet, Facebook, Inc.
3  * All rights reserved.
4  *
5  * This source code is licensed under both the BSD-style license (found in the
6  * LICENSE file in the root directory of this source tree) and the GPLv2 (found
7  * in the COPYING file in the root directory of this source tree).
8  * You may select, at your option, one of the above-listed licenses.
9  */
10 
11 #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 #if defined(__aarch64__) && !defined(_KERNEL)
23 #include <arm_neon.h>
24 #endif
25 #include "compiler.h"
26 #include "mem.h"
27 #include "debug.h"                 /* assert, DEBUGLOG, RAWLOG, g_debuglevel */
28 #include "error_private.h"
29 #define ZSTD_STATIC_LINKING_ONLY
30 #include "../zstd.h"
31 #define FSE_STATIC_LINKING_ONLY
32 #include "fse.h"
33 #define HUF_STATIC_LINKING_ONLY
34 #include "huf.h"
35 #ifndef XXH_STATIC_LINKING_ONLY
36 #  define XXH_STATIC_LINKING_ONLY  /* XXH64_state_t */
37 #endif
38 #include "xxhash.h"                /* XXH_reset, update, digest */
39 
40 #if defined (__cplusplus)
41 extern "C" {
42 #endif
43 
44 /* ---- static assert (debug) --- */
45 #define ZSTD_STATIC_ASSERT(c) DEBUG_STATIC_ASSERT(c)
46 #define ZSTD_isError ERR_isError   /* for inlining */
47 #define FSE_isError  ERR_isError
48 #define HUF_isError  ERR_isError
49 
50 
51 /*-*************************************
52 *  shared macros
53 ***************************************/
54 #undef MIN
55 #undef MAX
56 #define MIN(a,b) ((a)<(b) ? (a) : (b))
57 #define MAX(a,b) ((a)>(b) ? (a) : (b))
58 
59 /**
60  * Ignore: this is an internal helper.
61  *
62  * This is a helper function to help force C99-correctness during compilation.
63  * Under strict compilation modes, variadic macro arguments can't be empty.
64  * However, variadic function arguments can be. Using a function therefore lets
65  * us statically check that at least one (string) argument was passed,
66  * independent of the compilation flags.
67  */
68 static INLINE_KEYWORD UNUSED_ATTR
69 void _force_has_format_string(const char *format, ...) {
70   (void)format;
71 }
72 
73 /**
74  * Ignore: this is an internal helper.
75  *
76  * We want to force this function invocation to be syntactically correct, but
77  * we don't want to force runtime evaluation of its arguments.
78  */
79 #define _FORCE_HAS_FORMAT_STRING(...) \
80   if (0) { \
81     _force_has_format_string(__VA_ARGS__); \
82   }
83 
84 /**
85  * Return the specified error if the condition evaluates to true.
86  *
87  * In debug modes, prints additional information.
88  * In order to do that (particularly, printing the conditional that failed),
89  * this can't just wrap RETURN_ERROR().
90  */
91 #define RETURN_ERROR_IF(cond, err, ...) \
92   if (cond) { \
93     RAWLOG(3, "%s:%d: ERROR!: check %s failed, returning %s", \
94            __FILE__, __LINE__, ZSTD_QUOTE(cond), ZSTD_QUOTE(ERROR(err))); \
95     _FORCE_HAS_FORMAT_STRING(__VA_ARGS__); \
96     RAWLOG(3, ": " __VA_ARGS__); \
97     RAWLOG(3, "\n"); \
98     return ERROR(err); \
99   }
100 
101 /**
102  * Unconditionally return the specified error.
103  *
104  * In debug modes, prints additional information.
105  */
106 #define RETURN_ERROR(err, ...) \
107   do { \
108     RAWLOG(3, "%s:%d: ERROR!: unconditional check failed, returning %s", \
109            __FILE__, __LINE__, ZSTD_QUOTE(ERROR(err))); \
110     _FORCE_HAS_FORMAT_STRING(__VA_ARGS__); \
111     RAWLOG(3, ": " __VA_ARGS__); \
112     RAWLOG(3, "\n"); \
113     return ERROR(err); \
114   } while(0);
115 
116 /**
117  * If the provided expression evaluates to an error code, returns that error code.
118  *
119  * In debug modes, prints additional information.
120  */
121 #define FORWARD_IF_ERROR(err, ...) \
122   do { \
123     size_t const err_code = (err); \
124     if (ERR_isError(err_code)) { \
125       RAWLOG(3, "%s:%d: ERROR!: forwarding error in %s: %s", \
126              __FILE__, __LINE__, ZSTD_QUOTE(err), ERR_getErrorName(err_code)); \
127       _FORCE_HAS_FORMAT_STRING(__VA_ARGS__); \
128       RAWLOG(3, ": " __VA_ARGS__); \
129       RAWLOG(3, "\n"); \
130       return err_code; \
131     } \
132   } while(0);
133 
134 
135 /*-*************************************
136 *  Common constants
137 ***************************************/
138 #define ZSTD_OPT_NUM    (1<<12)
139 
140 #define ZSTD_REP_NUM      3                 /* number of repcodes */
141 #define ZSTD_REP_MOVE     (ZSTD_REP_NUM-1)
142 static const U32 repStartValue[ZSTD_REP_NUM] = { 1, 4, 8 };
143 
144 #define KB *(1 <<10)
145 #define MB *(1 <<20)
146 #define GB *(1U<<30)
147 
148 #define BIT7 128
149 #define BIT6  64
150 #define BIT5  32
151 #define BIT4  16
152 #define BIT1   2
153 #define BIT0   1
154 
155 #define ZSTD_WINDOWLOG_ABSOLUTEMIN 10
156 static const size_t ZSTD_fcs_fieldSize[4] = { 0, 2, 4, 8 };
157 static const size_t ZSTD_did_fieldSize[4] = { 0, 1, 2, 4 };
158 
159 #define ZSTD_FRAMEIDSIZE 4   /* magic number size */
160 
161 #define ZSTD_BLOCKHEADERSIZE 3   /* C standard doesn't allow `static const` variable to be init using another `static const` variable */
162 static const size_t ZSTD_blockHeaderSize = ZSTD_BLOCKHEADERSIZE;
163 typedef enum { bt_raw, bt_rle, bt_compressed, bt_reserved } blockType_e;
164 
165 #define ZSTD_FRAMECHECKSUMSIZE 4
166 
167 #define MIN_SEQUENCES_SIZE 1 /* nbSeq==0 */
168 #define MIN_CBLOCK_SIZE (1 /*litCSize*/ + 1 /* RLE or RAW */ + MIN_SEQUENCES_SIZE /* nbSeq==0 */)   /* for a non-null block */
169 
170 #define HufLog 12
171 typedef enum { set_basic, set_rle, set_compressed, set_repeat } symbolEncodingType_e;
172 
173 #define LONGNBSEQ 0x7F00
174 
175 #define MINMATCH 3
176 
177 #define Litbits  8
178 #define MaxLit ((1<<Litbits) - 1)
179 #define MaxML   52
180 #define MaxLL   35
181 #define DefaultMaxOff 28
182 #define MaxOff  31
183 #define MaxSeq MAX(MaxLL, MaxML)   /* Assumption : MaxOff < MaxLL,MaxML */
184 #define MLFSELog    9
185 #define LLFSELog    9
186 #define OffFSELog   8
187 #define MaxFSELog  MAX(MAX(MLFSELog, LLFSELog), OffFSELog)
188 
189 static const U32 LL_bits[MaxLL+1] = { 0, 0, 0, 0, 0, 0, 0, 0,
190                                       0, 0, 0, 0, 0, 0, 0, 0,
191                                       1, 1, 1, 1, 2, 2, 3, 3,
192                                       4, 6, 7, 8, 9,10,11,12,
193                                      13,14,15,16 };
194 static const S16 LL_defaultNorm[MaxLL+1] = { 4, 3, 2, 2, 2, 2, 2, 2,
195                                              2, 2, 2, 2, 2, 1, 1, 1,
196                                              2, 2, 2, 2, 2, 2, 2, 2,
197                                              2, 3, 2, 1, 1, 1, 1, 1,
198                                             -1,-1,-1,-1 };
199 #define LL_DEFAULTNORMLOG 6  /* for static allocation */
200 static const U32 LL_defaultNormLog = LL_DEFAULTNORMLOG;
201 
202 static const U32 ML_bits[MaxML+1] = { 0, 0, 0, 0, 0, 0, 0, 0,
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                                       1, 1, 1, 1, 2, 2, 3, 3,
207                                       4, 4, 5, 7, 8, 9,10,11,
208                                      12,13,14,15,16 };
209 static const S16 ML_defaultNorm[MaxML+1] = { 1, 4, 3, 2, 2, 2, 2, 2,
210                                              2, 1, 1, 1, 1, 1, 1, 1,
211                                              1, 1, 1, 1, 1, 1, 1, 1,
212                                              1, 1, 1, 1, 1, 1, 1, 1,
213                                              1, 1, 1, 1, 1, 1, 1, 1,
214                                              1, 1, 1, 1, 1, 1,-1,-1,
215                                             -1,-1,-1,-1,-1 };
216 #define ML_DEFAULTNORMLOG 6  /* for static allocation */
217 static const U32 ML_defaultNormLog = ML_DEFAULTNORMLOG;
218 
219 static const S16 OF_defaultNorm[DefaultMaxOff+1] = { 1, 1, 1, 1, 1, 1, 2, 2,
220                                                      2, 1, 1, 1, 1, 1, 1, 1,
221                                                      1, 1, 1, 1, 1, 1, 1, 1,
222                                                     -1,-1,-1,-1,-1 };
223 #define OF_DEFAULTNORMLOG 5  /* for static allocation */
224 static const U32 OF_defaultNormLog = OF_DEFAULTNORMLOG;
225 
226 
227 /*-*******************************************
228 *  Shared functions to include for inlining
229 *********************************************/
230 static void ZSTD_copy8(void* dst, const void* src) {
231 #if defined(__aarch64__) && !defined(_KERNEL)
232     vst1_u8((uint8_t*)dst, vld1_u8((const uint8_t*)src));
233 #else
234     memcpy(dst, src, 8);
235 #endif
236 }
237 
238 #define COPY8(d,s) { ZSTD_copy8(d,s); d+=8; s+=8; }
239 static void ZSTD_copy16(void* dst, const void* src) {
240 #if defined(__aarch64__) && !defined(_KERNEL)
241     vst1q_u8((uint8_t*)dst, vld1q_u8((const uint8_t*)src));
242 #else
243     memcpy(dst, src, 16);
244 #endif
245 }
246 #define COPY16(d,s) { ZSTD_copy16(d,s); d+=16; s+=16; }
247 
248 #define WILDCOPY_OVERLENGTH 32
249 #define WILDCOPY_VECLEN 16
250 
251 typedef enum {
252     ZSTD_no_overlap,
253     ZSTD_overlap_src_before_dst
254     /*  ZSTD_overlap_dst_before_src, */
255 } ZSTD_overlap_e;
256 
257 /*! ZSTD_wildcopy() :
258  *  Custom version of memcpy(), can over read/write up to WILDCOPY_OVERLENGTH bytes (if length==0)
259  *  @param ovtype controls the overlap detection
260  *         - ZSTD_no_overlap: The source and destination are guaranteed to be at least WILDCOPY_VECLEN bytes apart.
261  *         - ZSTD_overlap_src_before_dst: The src and dst may overlap, but they MUST be at least 8 bytes apart.
262  *           The src buffer must be before the dst buffer.
263  */
264 MEM_STATIC FORCE_INLINE_ATTR
265 void ZSTD_wildcopy(void* dst, const void* src, ptrdiff_t length, ZSTD_overlap_e const ovtype)
266 {
267     ptrdiff_t diff = (BYTE*)dst - (const BYTE*)src;
268     const BYTE* ip = (const BYTE*)src;
269     BYTE* op = (BYTE*)dst;
270     BYTE* const oend = op + length;
271 
272     assert(diff >= 8 || (ovtype == ZSTD_no_overlap && diff <= -WILDCOPY_VECLEN));
273 
274     if (ovtype == ZSTD_overlap_src_before_dst && diff < WILDCOPY_VECLEN) {
275         /* Handle short offset copies. */
276         do {
277             COPY8(op, ip)
278         } while (op < oend);
279     } else {
280         assert(diff >= WILDCOPY_VECLEN || diff <= -WILDCOPY_VECLEN);
281         /* Separate out the first COPY16() call because the copy length is
282          * almost certain to be short, so the branches have different
283          * probabilities. Since it is almost certain to be short, only do
284          * one COPY16() in the first call. Then, do two calls per loop since
285          * at that point it is more likely to have a high trip count.
286          */
287 #ifndef __aarch64__
288         do {
289             COPY16(op, ip);
290         }
291         while (op < oend);
292 #else
293         COPY16(op, ip);
294         if (op >= oend) return;
295         do {
296             COPY16(op, ip);
297             COPY16(op, ip);
298         }
299         while (op < oend);
300 #endif
301     }
302 }
303 
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         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 
324 /*-*******************************************
325 *  Private declarations
326 *********************************************/
327 typedef struct seqDef_s {
328     U32 offset;
329     U16 litLength;
330     U16 matchLength;
331 } seqDef;
332 
333 typedef struct {
334     seqDef* sequencesStart;
335     seqDef* sequences;
336     BYTE* litStart;
337     BYTE* lit;
338     BYTE* llCode;
339     BYTE* mlCode;
340     BYTE* ofCode;
341     size_t maxNbSeq;
342     size_t maxNbLit;
343     U32   longLengthID;   /* 0 == no longLength; 1 == Lit.longLength; 2 == Match.longLength; */
344     U32   longLengthPos;
345 } seqStore_t;
346 
347 typedef struct {
348     U32 litLength;
349     U32 matchLength;
350 } ZSTD_sequenceLength;
351 
352 /**
353  * Returns the ZSTD_sequenceLength for the given sequences. It handles the decoding of long sequences
354  * indicated by longLengthPos and longLengthID, and adds MINMATCH back to matchLength.
355  */
356 MEM_STATIC ZSTD_sequenceLength ZSTD_getSequenceLength(seqStore_t const* seqStore, seqDef const* seq)
357 {
358     ZSTD_sequenceLength seqLen;
359     seqLen.litLength = seq->litLength;
360     seqLen.matchLength = seq->matchLength + MINMATCH;
361     if (seqStore->longLengthPos == (U32)(seq - seqStore->sequencesStart)) {
362         if (seqStore->longLengthID == 1) {
363             seqLen.litLength += 0xFFFF;
364         }
365         if (seqStore->longLengthID == 2) {
366             seqLen.matchLength += 0xFFFF;
367         }
368     }
369     return seqLen;
370 }
371 
372 /**
373  * Contains the compressed frame size and an upper-bound for the decompressed frame size.
374  * Note: before using `compressedSize`, check for errors using ZSTD_isError().
375  *       similarly, before using `decompressedBound`, check for errors using:
376  *          `decompressedBound != ZSTD_CONTENTSIZE_ERROR`
377  */
378 typedef struct {
379     size_t compressedSize;
380     unsigned long long decompressedBound;
381 } ZSTD_frameSizeInfo;   /* decompress & legacy */
382 
383 const seqStore_t* ZSTD_getSeqStore(const ZSTD_CCtx* ctx);   /* compress & dictBuilder */
384 void ZSTD_seqToCodes(const seqStore_t* seqStorePtr);   /* compress, dictBuilder, decodeCorpus (shouldn't get its definition from here) */
385 
386 /* custom memory allocation functions */
387 void* ZSTD_malloc(size_t size, ZSTD_customMem customMem);
388 void* ZSTD_calloc(size_t size, ZSTD_customMem customMem);
389 void ZSTD_free(void* ptr, ZSTD_customMem customMem);
390 
391 
392 MEM_STATIC U32 ZSTD_highbit32(U32 val)   /* compress, dictBuilder, decodeCorpus */
393 {
394     assert(val != 0);
395     {
396 #   if defined(_MSC_VER)   /* Visual */
397         unsigned long r=0;
398         return _BitScanReverse(&r, val) ? (unsigned)r : 0;
399 #   elif defined(__GNUC__) && (__GNUC__ >= 3)   /* GCC Intrinsic */
400         return __builtin_clz (val) ^ 31;
401 #   elif defined(__ICCARM__)    /* IAR Intrinsic */
402         return 31 - __CLZ(val);
403 #   else   /* Software version */
404         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 };
405         U32 v = val;
406         v |= v >> 1;
407         v |= v >> 2;
408         v |= v >> 4;
409         v |= v >> 8;
410         v |= v >> 16;
411         return DeBruijnClz[(v * 0x07C4ACDDU) >> 27];
412 #   endif
413     }
414 }
415 
416 
417 /* ZSTD_invalidateRepCodes() :
418  * ensures next compression will not use repcodes from previous block.
419  * Note : only works with regular variant;
420  *        do not use with extDict variant ! */
421 void ZSTD_invalidateRepCodes(ZSTD_CCtx* cctx);   /* zstdmt, adaptive_compression (shouldn't get this definition from here) */
422 
423 
424 typedef struct {
425     blockType_e blockType;
426     U32 lastBlock;
427     U32 origSize;
428 } blockProperties_t;   /* declared here for decompress and fullbench */
429 
430 /*! ZSTD_getcBlockSize() :
431  *  Provides the size of compressed block from block header `src` */
432 /* Used by: decompress, fullbench (does not get its definition from here) */
433 size_t ZSTD_getcBlockSize(const void* src, size_t srcSize,
434                           blockProperties_t* bpPtr);
435 
436 /*! ZSTD_decodeSeqHeaders() :
437  *  decode sequence header from src */
438 /* Used by: decompress, fullbench (does not get its definition from here) */
439 size_t ZSTD_decodeSeqHeaders(ZSTD_DCtx* dctx, int* nbSeqPtr,
440                        const void* src, size_t srcSize);
441 
442 
443 #if defined (__cplusplus)
444 }
445 #endif
446 
447 #endif   /* ZSTD_CCOMMON_H_MODULE */
448