xref: /freebsd/sys/contrib/openzfs/module/zstd/lib/common/zstd_internal.h (revision 5ca8e32633c4ffbbcd6762e5888b6a4ba0708c6c)
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(ZSTD_NO_INTRINSICS) && defined(__ARM_NEON)
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 FSE_isError  ERR_isError
47 #define HUF_isError  ERR_isError
48 
49 
50 /*-*************************************
51 *  shared macros
52 ***************************************/
53 #undef MIN
54 #undef MAX
55 #define MIN(a,b) ((a)<(b) ? (a) : (b))
56 #define MAX(a,b) ((a)>(b) ? (a) : (b))
57 
58 /**
59  * Ignore: this is an internal helper.
60  *
61  * This is a helper function to help force C99-correctness during compilation.
62  * Under strict compilation modes, variadic macro arguments can't be empty.
63  * However, variadic function arguments can be. Using a function therefore lets
64  * us statically check that at least one (string) argument was passed,
65  * independent of the compilation flags.
66  */
67 static INLINE_KEYWORD UNUSED_ATTR
68 void _force_has_format_string(const char *format, ...) {
69   (void)format;
70 }
71 
72 /**
73  * Ignore: this is an internal helper.
74  *
75  * We want to force this function invocation to be syntactically correct, but
76  * we don't want to force runtime evaluation of its arguments.
77  */
78 #define _FORCE_HAS_FORMAT_STRING(...) \
79   if (0) { \
80     _force_has_format_string(__VA_ARGS__); \
81   }
82 
83 /**
84  * Return the specified error if the condition evaluates to true.
85  *
86  * In debug modes, prints additional information.
87  * In order to do that (particularly, printing the conditional that failed),
88  * this can't just wrap RETURN_ERROR().
89  */
90 #define RETURN_ERROR_IF(cond, err, ...) \
91   if (cond) { \
92     RAWLOG(3, "%s:%d: ERROR!: check %s failed, returning %s", \
93            __FILE__, __LINE__, ZSTD_QUOTE(cond), ZSTD_QUOTE(ERROR(err))); \
94     _FORCE_HAS_FORMAT_STRING(__VA_ARGS__); \
95     RAWLOG(3, ": " __VA_ARGS__); \
96     RAWLOG(3, "\n"); \
97     return ERROR(err); \
98   }
99 
100 /**
101  * Unconditionally return the specified error.
102  *
103  * In debug modes, prints additional information.
104  */
105 #define RETURN_ERROR(err, ...) \
106   do { \
107     RAWLOG(3, "%s:%d: ERROR!: unconditional check failed, returning %s", \
108            __FILE__, __LINE__, ZSTD_QUOTE(ERROR(err))); \
109     _FORCE_HAS_FORMAT_STRING(__VA_ARGS__); \
110     RAWLOG(3, ": " __VA_ARGS__); \
111     RAWLOG(3, "\n"); \
112     return ERROR(err); \
113   } while(0);
114 
115 /**
116  * If the provided expression evaluates to an error code, returns that error code.
117  *
118  * In debug modes, prints additional information.
119  */
120 #define FORWARD_IF_ERROR(err, ...) \
121   do { \
122     size_t const err_code = (err); \
123     if (ERR_isError(err_code)) { \
124       RAWLOG(3, "%s:%d: ERROR!: forwarding error in %s: %s", \
125              __FILE__, __LINE__, ZSTD_QUOTE(err), ERR_getErrorName(err_code)); \
126       _FORCE_HAS_FORMAT_STRING(__VA_ARGS__); \
127       RAWLOG(3, ": " __VA_ARGS__); \
128       RAWLOG(3, "\n"); \
129       return err_code; \
130     } \
131   } while(0);
132 
133 
134 /*-*************************************
135 *  Common constants
136 ***************************************/
137 #define ZSTD_OPT_NUM    (1<<12)
138 
139 #define ZSTD_REP_NUM      3                 /* number of repcodes */
140 #define ZSTD_REP_MOVE     (ZSTD_REP_NUM-1)
141 static const U32 repStartValue[ZSTD_REP_NUM] = { 1, 4, 8 };
142 
143 #define KB *(1 <<10)
144 #define MB *(1 <<20)
145 #define GB *(1U<<30)
146 
147 #define BIT7 128
148 #define BIT6  64
149 #define BIT5  32
150 #define BIT4  16
151 #define BIT1   2
152 #define BIT0   1
153 
154 #define ZSTD_WINDOWLOG_ABSOLUTEMIN 10
155 static const size_t ZSTD_fcs_fieldSize[4] = { 0, 2, 4, 8 };
156 static const size_t ZSTD_did_fieldSize[4] = { 0, 1, 2, 4 };
157 
158 #define ZSTD_FRAMEIDSIZE 4   /* magic number size */
159 
160 #define ZSTD_BLOCKHEADERSIZE 3   /* C standard doesn't allow `static const` variable to be init using another `static const` variable */
161 static const size_t ZSTD_blockHeaderSize = ZSTD_BLOCKHEADERSIZE;
162 typedef enum { bt_raw, bt_rle, bt_compressed, bt_reserved } blockType_e;
163 
164 #define ZSTD_FRAMECHECKSUMSIZE 4
165 
166 #define MIN_SEQUENCES_SIZE 1 /* nbSeq==0 */
167 #define MIN_CBLOCK_SIZE (1 /*litCSize*/ + 1 /* RLE or RAW */ + MIN_SEQUENCES_SIZE /* nbSeq==0 */)   /* for a non-null block */
168 
169 #define HufLog 12
170 typedef enum { set_basic, set_rle, set_compressed, set_repeat } symbolEncodingType_e;
171 
172 #define LONGNBSEQ 0x7F00
173 
174 #define MINMATCH 3
175 
176 #define Litbits  8
177 #define MaxLit ((1<<Litbits) - 1)
178 #define MaxML   52
179 #define MaxLL   35
180 #define DefaultMaxOff 28
181 #define MaxOff  31
182 #define MaxSeq MAX(MaxLL, MaxML)   /* Assumption : MaxOff < MaxLL,MaxML */
183 #define MLFSELog    9
184 #define LLFSELog    9
185 #define OffFSELog   8
186 #define MaxFSELog  MAX(MAX(MLFSELog, LLFSELog), OffFSELog)
187 
188 static const U32 LL_bits[MaxLL+1] = { 0, 0, 0, 0, 0, 0, 0, 0,
189                                       0, 0, 0, 0, 0, 0, 0, 0,
190                                       1, 1, 1, 1, 2, 2, 3, 3,
191                                       4, 6, 7, 8, 9,10,11,12,
192                                      13,14,15,16 };
193 static const S16 LL_defaultNorm[MaxLL+1] = { 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 #define LL_DEFAULTNORMLOG 6  /* for static allocation */
199 static const U32 LL_defaultNormLog = LL_DEFAULTNORMLOG;
200 
201 static const U32 ML_bits[MaxML+1] = { 0, 0, 0, 0, 0, 0, 0, 0,
202                                       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                                       1, 1, 1, 1, 2, 2, 3, 3,
206                                       4, 4, 5, 7, 8, 9,10,11,
207                                      12,13,14,15,16 };
208 static const S16 ML_defaultNorm[MaxML+1] = { 1, 4, 3, 2, 2, 2, 2, 2,
209                                              2, 1, 1, 1, 1, 1, 1, 1,
210                                              1, 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 };
215 #define ML_DEFAULTNORMLOG 6  /* for static allocation */
216 static const U32 ML_defaultNormLog = ML_DEFAULTNORMLOG;
217 
218 static const S16 OF_defaultNorm[DefaultMaxOff+1] = { 1, 1, 1, 1, 1, 1, 2, 2,
219                                                      2, 1, 1, 1, 1, 1, 1, 1,
220                                                      1, 1, 1, 1, 1, 1, 1, 1,
221                                                     -1,-1,-1,-1,-1 };
222 #define OF_DEFAULTNORMLOG 5  /* for static allocation */
223 static const U32 OF_defaultNormLog = OF_DEFAULTNORMLOG;
224 
225 
226 /*-*******************************************
227 *  Shared functions to include for inlining
228 *********************************************/
229 static void ZSTD_copy8(void* dst, const void* src) {
230 #if !defined(ZSTD_NO_INTRINSICS) && defined(__ARM_NEON)
231     vst1_u8((uint8_t*)dst, vld1_u8((const uint8_t*)src));
232 #else
233     memcpy(dst, src, 8);
234 #endif
235 }
236 
237 #define COPY8(d,s) { ZSTD_copy8(d,s); d+=8; s+=8; }
238 static void ZSTD_copy16(void* dst, const void* src) {
239 #if !defined(ZSTD_NO_INTRINSICS) && defined(__ARM_NEON)
240     vst1q_u8((uint8_t*)dst, vld1q_u8((const uint8_t*)src));
241 #else
242     memcpy(dst, src, 16);
243 #endif
244 }
245 #define COPY16(d,s) { ZSTD_copy16(d,s); d+=16; s+=16; }
246 
247 #define WILDCOPY_OVERLENGTH 32
248 #define WILDCOPY_VECLEN 16
249 
250 typedef enum {
251     ZSTD_no_overlap,
252     ZSTD_overlap_src_before_dst
253     /*  ZSTD_overlap_dst_before_src, */
254 } ZSTD_overlap_e;
255 
256 /*! ZSTD_wildcopy() :
257  *  Custom version of memcpy(), can over read/write up to WILDCOPY_OVERLENGTH bytes (if length==0)
258  *  @param ovtype controls the overlap detection
259  *         - ZSTD_no_overlap: The source and destination are guaranteed to be at least WILDCOPY_VECLEN bytes apart.
260  *         - ZSTD_overlap_src_before_dst: The src and dst may overlap, but they MUST be at least 8 bytes apart.
261  *           The src buffer must be before the dst buffer.
262  */
263 MEM_STATIC FORCE_INLINE_ATTR
264 void ZSTD_wildcopy(void* dst, const void* src, ptrdiff_t length, ZSTD_overlap_e const ovtype)
265 {
266     ptrdiff_t diff = (BYTE*)dst - (const BYTE*)src;
267     const BYTE* ip = (const BYTE*)src;
268     BYTE* op = (BYTE*)dst;
269     BYTE* const oend = op + length;
270 
271     assert(diff >= 8 || (ovtype == ZSTD_no_overlap && diff <= -WILDCOPY_VECLEN));
272 
273     if (ovtype == ZSTD_overlap_src_before_dst && diff < WILDCOPY_VECLEN) {
274         /* Handle short offset copies. */
275         do {
276             COPY8(op, ip)
277         } while (op < oend);
278     } else {
279         assert(diff >= WILDCOPY_VECLEN || diff <= -WILDCOPY_VECLEN);
280         /* Separate out the first COPY16() call because the copy length is
281          * almost certain to be short, so the branches have different
282          * probabilities. Since it is almost certain to be short, only do
283          * one COPY16() in the first call. Then, do two calls per loop since
284          * at that point it is more likely to have a high trip count.
285          */
286 #ifndef __aarch64__
287         do {
288             COPY16(op, ip);
289         }
290         while (op < oend);
291 #else
292         COPY16(op, ip);
293         if (op >= oend) return;
294         do {
295             COPY16(op, ip);
296             COPY16(op, ip);
297         }
298         while (op < oend);
299 #endif
300     }
301 }
302 
303 MEM_STATIC size_t ZSTD_limitCopy(void* dst, size_t dstCapacity, const void* src, size_t srcSize)
304 {
305     size_t const length = MIN(dstCapacity, srcSize);
306     if (length > 0) {
307         memcpy(dst, src, length);
308     }
309     return length;
310 }
311 
312 /* define "workspace is too large" as this number of times larger than needed */
313 #define ZSTD_WORKSPACETOOLARGE_FACTOR 3
314 
315 /* when workspace is continuously too large
316  * during at least this number of times,
317  * context's memory usage is considered wasteful,
318  * because it's sized to handle a worst case scenario which rarely happens.
319  * In which case, resize it down to free some memory */
320 #define ZSTD_WORKSPACETOOLARGE_MAXDURATION 128
321 
322 
323 /*-*******************************************
324 *  Private declarations
325 *********************************************/
326 typedef struct seqDef_s {
327     U32 offset;
328     U16 litLength;
329     U16 matchLength;
330 } seqDef;
331 
332 typedef struct {
333     seqDef* sequencesStart;
334     seqDef* sequences;
335     BYTE* litStart;
336     BYTE* lit;
337     BYTE* llCode;
338     BYTE* mlCode;
339     BYTE* ofCode;
340     size_t maxNbSeq;
341     size_t maxNbLit;
342     U32   longLengthID;   /* 0 == no longLength; 1 == Lit.longLength; 2 == Match.longLength; */
343     U32   longLengthPos;
344 } seqStore_t;
345 
346 typedef struct {
347     U32 litLength;
348     U32 matchLength;
349 } ZSTD_sequenceLength;
350 
351 /**
352  * Returns the ZSTD_sequenceLength for the given sequences. It handles the decoding of long sequences
353  * indicated by longLengthPos and longLengthID, and adds MINMATCH back to matchLength.
354  */
355 MEM_STATIC ZSTD_sequenceLength ZSTD_getSequenceLength(seqStore_t const* seqStore, seqDef const* seq)
356 {
357     ZSTD_sequenceLength seqLen;
358     seqLen.litLength = seq->litLength;
359     seqLen.matchLength = seq->matchLength + MINMATCH;
360     if (seqStore->longLengthPos == (U32)(seq - seqStore->sequencesStart)) {
361         if (seqStore->longLengthID == 1) {
362             seqLen.litLength += 0xFFFF;
363         }
364         if (seqStore->longLengthID == 2) {
365             seqLen.matchLength += 0xFFFF;
366         }
367     }
368     return seqLen;
369 }
370 
371 /**
372  * Contains the compressed frame size and an upper-bound for the decompressed frame size.
373  * Note: before using `compressedSize`, check for errors using ZSTD_isError().
374  *       similarly, before using `decompressedBound`, check for errors using:
375  *          `decompressedBound != ZSTD_CONTENTSIZE_ERROR`
376  */
377 typedef struct {
378     size_t compressedSize;
379     unsigned long long decompressedBound;
380 } ZSTD_frameSizeInfo;   /* decompress & legacy */
381 
382 const seqStore_t* ZSTD_getSeqStore(const ZSTD_CCtx* ctx);   /* compress & dictBuilder */
383 void ZSTD_seqToCodes(const seqStore_t* seqStorePtr);   /* compress, dictBuilder, decodeCorpus (shouldn't get its definition from here) */
384 
385 /* custom memory allocation functions */
386 void* ZSTD_malloc(size_t size, ZSTD_customMem customMem);
387 void* ZSTD_calloc(size_t size, ZSTD_customMem customMem);
388 void ZSTD_free(void* ptr, ZSTD_customMem customMem);
389 
390 
391 MEM_STATIC U32 ZSTD_highbit32(U32 val)   /* compress, dictBuilder, decodeCorpus */
392 {
393     assert(val != 0);
394     {
395 #   if defined(_MSC_VER)   /* Visual */
396         unsigned long r=0;
397         return _BitScanReverse(&r, val) ? (unsigned)r : 0;
398 #   elif defined(__GNUC__) && (__GNUC__ >= 3)   /* GCC Intrinsic */
399         return __builtin_clz (val) ^ 31;
400 #   elif defined(__ICCARM__)    /* IAR Intrinsic */
401         return 31 - __CLZ(val);
402 #   else   /* Software version */
403         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 };
404         U32 v = val;
405         v |= v >> 1;
406         v |= v >> 2;
407         v |= v >> 4;
408         v |= v >> 8;
409         v |= v >> 16;
410         return DeBruijnClz[(v * 0x07C4ACDDU) >> 27];
411 #   endif
412     }
413 }
414 
415 
416 /* ZSTD_invalidateRepCodes() :
417  * ensures next compression will not use repcodes from previous block.
418  * Note : only works with regular variant;
419  *        do not use with extDict variant ! */
420 void ZSTD_invalidateRepCodes(ZSTD_CCtx* cctx);   /* zstdmt, adaptive_compression (shouldn't get this definition from here) */
421 
422 
423 typedef struct {
424     blockType_e blockType;
425     U32 lastBlock;
426     U32 origSize;
427 } blockProperties_t;   /* declared here for decompress and fullbench */
428 
429 /*! ZSTD_getcBlockSize() :
430  *  Provides the size of compressed block from block header `src` */
431 /* Used by: decompress, fullbench (does not get its definition from here) */
432 size_t ZSTD_getcBlockSize(const void* src, size_t srcSize,
433                           blockProperties_t* bpPtr);
434 
435 /*! ZSTD_decodeSeqHeaders() :
436  *  decode sequence header from src */
437 /* Used by: decompress, fullbench (does not get its definition from here) */
438 size_t ZSTD_decodeSeqHeaders(ZSTD_DCtx* dctx, int* nbSeqPtr,
439                        const void* src, size_t srcSize);
440 
441 
442 #if defined (__cplusplus)
443 }
444 #endif
445 
446 #endif   /* ZSTD_CCOMMON_H_MODULE */
447