1 /* SPDX-License-Identifier: (GPL-2.0 or BSD-3-Clause-Clear) */
2 /**
3 * Copyright (c) 2016-present, Yann Collet, Facebook, Inc.
4 * All rights reserved.
5 */
6
7 #ifndef ZSTD_CCOMMON_H_MODULE
8 #define ZSTD_CCOMMON_H_MODULE
9
10 /*-*******************************************************
11 * Compiler specifics
12 *********************************************************/
13 #define FORCE_INLINE static __always_inline
14 #define FORCE_NOINLINE static noinline
15
16 /*-*************************************
17 * Dependencies
18 ***************************************/
19 #include "error_private.h"
20 #include "mem.h"
21 #include <linux/compiler.h>
22 #include <linux/kernel.h>
23 #include <linux/xxhash.h>
24 #include <linux/zstd.h>
25
26 /*-*************************************
27 * shared macros
28 ***************************************/
29 #define MIN(a, b) ((a) < (b) ? (a) : (b))
30 #define MAX(a, b) ((a) > (b) ? (a) : (b))
31 #define CHECK_F(f) \
32 { \
33 size_t const errcod = f; \
34 if (ERR_isError(errcod)) \
35 return errcod; \
36 } /* check and Forward error code */
37 #define CHECK_E(f, e) \
38 { \
39 size_t const errcod = f; \
40 if (ERR_isError(errcod)) \
41 return ERROR(e); \
42 } /* check and send Error code */
43 #define ZSTD_STATIC_ASSERT(c) \
44 { \
45 enum { ZSTD_static_assert = 1 / (int)(!!(c)) }; \
46 }
47
48 /*-*************************************
49 * Common constants
50 ***************************************/
51 #define ZSTD_OPT_NUM (1 << 12)
52 #define ZSTD_DICT_MAGIC 0xEC30A437 /* v0.7+ */
53
54 #define ZSTD_REP_NUM 3 /* number of repcodes */
55 #define ZSTD_REP_CHECK (ZSTD_REP_NUM) /* number of repcodes to check by the optimal parser */
56 #define ZSTD_REP_MOVE (ZSTD_REP_NUM - 1)
57 #define ZSTD_REP_MOVE_OPT (ZSTD_REP_NUM)
58 static const U32 repStartValue[ZSTD_REP_NUM] = {1, 4, 8};
59
60 #define KB *(1 << 10)
61 #define MB *(1 << 20)
62 #define GB *(1U << 30)
63
64 #define BIT7 128
65 #define BIT6 64
66 #define BIT5 32
67 #define BIT4 16
68 #define BIT1 2
69 #define BIT0 1
70
71 #define ZSTD_WINDOWLOG_ABSOLUTEMIN 10
72 static const size_t ZSTD_fcs_fieldSize[4] = {0, 2, 4, 8};
73 static const size_t ZSTD_did_fieldSize[4] = {0, 1, 2, 4};
74
75 #define ZSTD_BLOCKHEADERSIZE 3 /* C standard doesn't allow `static const` variable to be init using another `static const` variable */
76 static const size_t ZSTD_blockHeaderSize = ZSTD_BLOCKHEADERSIZE;
77 typedef enum { bt_raw, bt_rle, bt_compressed, bt_reserved } blockType_e;
78
79 #define MIN_SEQUENCES_SIZE 1 /* nbSeq==0 */
80 #define MIN_CBLOCK_SIZE (1 /*litCSize*/ + 1 /* RLE or RAW */ + MIN_SEQUENCES_SIZE /* nbSeq==0 */) /* for a non-null block */
81
82 #define HufLog 12
83 typedef enum { set_basic, set_rle, set_compressed, set_repeat } symbolEncodingType_e;
84
85 #define LONGNBSEQ 0x7F00
86
87 #define MINMATCH 3
88 #define EQUAL_READ32 4
89
90 #define Litbits 8
91 #define MaxLit ((1 << Litbits) - 1)
92 #define MaxML 52
93 #define MaxLL 35
94 #define MaxOff 28
95 #define MaxSeq MAX(MaxLL, MaxML) /* Assumption : MaxOff < MaxLL,MaxML */
96 #define MLFSELog 9
97 #define LLFSELog 9
98 #define OffFSELog 8
99
100 static const U32 LL_bits[MaxLL + 1] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 3, 3, 4, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16};
101 static const S16 LL_defaultNorm[MaxLL + 1] = {4, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 2, 1, 1, 1, 1, 1, -1, -1, -1, -1};
102 #define LL_DEFAULTNORMLOG 6 /* for static allocation */
103 static const U32 LL_defaultNormLog = LL_DEFAULTNORMLOG;
104
105 static const U32 ML_bits[MaxML + 1] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
106 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 3, 3, 4, 4, 5, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16};
107 static const S16 ML_defaultNorm[MaxML + 1] = {1, 4, 3, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
108 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1};
109 #define ML_DEFAULTNORMLOG 6 /* for static allocation */
110 static const U32 ML_defaultNormLog = ML_DEFAULTNORMLOG;
111
112 static const S16 OF_defaultNorm[MaxOff + 1] = {1, 1, 1, 1, 1, 1, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1};
113 #define OF_DEFAULTNORMLOG 5 /* for static allocation */
114 static const U32 OF_defaultNormLog = OF_DEFAULTNORMLOG;
115
116 /*-*******************************************
117 * Shared functions to include for inlining
118 *********************************************/
ZSTD_copy8(void * dst,const void * src)119 ZSTD_STATIC void ZSTD_copy8(void *dst, const void *src) {
120 memcpy(dst, src, 8);
121 }
122 /*! ZSTD_wildcopy() :
123 * custom version of memcpy(), can copy up to 7 bytes too many (8 bytes if length==0) */
124 #define WILDCOPY_OVERLENGTH 8
ZSTD_wildcopy(void * dst,const void * src,ptrdiff_t length)125 ZSTD_STATIC void ZSTD_wildcopy(void *dst, const void *src, ptrdiff_t length)
126 {
127 const BYTE* ip = (const BYTE*)src;
128 BYTE* op = (BYTE*)dst;
129 BYTE* const oend = op + length;
130 /* Work around https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81388.
131 * Avoid the bad case where the loop only runs once by handling the
132 * special case separately. This doesn't trigger the bug because it
133 * doesn't involve pointer/integer overflow.
134 */
135 if (length <= 8)
136 return ZSTD_copy8(dst, src);
137 do {
138 ZSTD_copy8(op, ip);
139 op += 8;
140 ip += 8;
141 } while (op < oend);
142 }
143
144 /*-*******************************************
145 * Private interfaces
146 *********************************************/
147 typedef struct ZSTD_stats_s ZSTD_stats_t;
148
149 typedef struct {
150 U32 off;
151 U32 len;
152 } ZSTD_match_t;
153
154 typedef struct {
155 U32 price;
156 U32 off;
157 U32 mlen;
158 U32 litlen;
159 U32 rep[ZSTD_REP_NUM];
160 } ZSTD_optimal_t;
161
162 typedef struct seqDef_s {
163 U32 offset;
164 U16 litLength;
165 U16 matchLength;
166 } seqDef;
167
168 typedef struct {
169 seqDef *sequencesStart;
170 seqDef *sequences;
171 BYTE *litStart;
172 BYTE *lit;
173 BYTE *llCode;
174 BYTE *mlCode;
175 BYTE *ofCode;
176 U32 longLengthID; /* 0 == no longLength; 1 == Lit.longLength; 2 == Match.longLength; */
177 U32 longLengthPos;
178 /* opt */
179 ZSTD_optimal_t *priceTable;
180 ZSTD_match_t *matchTable;
181 U32 *matchLengthFreq;
182 U32 *litLengthFreq;
183 U32 *litFreq;
184 U32 *offCodeFreq;
185 U32 matchLengthSum;
186 U32 matchSum;
187 U32 litLengthSum;
188 U32 litSum;
189 U32 offCodeSum;
190 U32 log2matchLengthSum;
191 U32 log2matchSum;
192 U32 log2litLengthSum;
193 U32 log2litSum;
194 U32 log2offCodeSum;
195 U32 factor;
196 U32 staticPrices;
197 U32 cachedPrice;
198 U32 cachedLitLength;
199 const BYTE *cachedLiterals;
200 } seqStore_t;
201
202 const seqStore_t *ZSTD_getSeqStore(const ZSTD_CCtx *ctx);
203 void ZSTD_seqToCodes(const seqStore_t *seqStorePtr);
204 int ZSTD_isSkipFrame(ZSTD_DCtx *dctx);
205
206 /*= Custom memory allocation functions */
207 typedef void *(*ZSTD_allocFunction)(void *opaque, size_t size);
208 typedef void (*ZSTD_freeFunction)(void *opaque, void *address);
209 typedef struct {
210 ZSTD_allocFunction customAlloc;
211 ZSTD_freeFunction customFree;
212 void *opaque;
213 } ZSTD_customMem;
214
215 void *ZSTD_malloc(size_t size, ZSTD_customMem customMem);
216 void ZSTD_free(void *ptr, ZSTD_customMem customMem);
217
218 /*====== stack allocation ======*/
219
220 typedef struct {
221 void *ptr;
222 const void *end;
223 } ZSTD_stack;
224
225 #define ZSTD_ALIGN(x) ALIGN(x, sizeof(size_t))
226 #define ZSTD_PTR_ALIGN(p) PTR_ALIGN(p, sizeof(size_t))
227
228 ZSTD_customMem ZSTD_initStack(void *workspace, size_t workspaceSize);
229
230 void *ZSTD_stackAllocAll(void *opaque, size_t *size);
231 void *ZSTD_stackAlloc(void *opaque, size_t size);
232 void ZSTD_stackFree(void *opaque, void *address);
233
234 /*====== common function ======*/
235
ZSTD_highbit32(U32 val)236 ZSTD_STATIC U32 ZSTD_highbit32(U32 val) { return 31 - __builtin_clz(val); }
237
238 /* hidden functions */
239
240 /* ZSTD_invalidateRepCodes() :
241 * ensures next compression will not use repcodes from previous block.
242 * Note : only works with regular variant;
243 * do not use with extDict variant ! */
244 void ZSTD_invalidateRepCodes(ZSTD_CCtx *cctx);
245
246 size_t ZSTD_freeCCtx(ZSTD_CCtx *cctx);
247 size_t ZSTD_freeDCtx(ZSTD_DCtx *dctx);
248 size_t ZSTD_freeCDict(ZSTD_CDict *cdict);
249 size_t ZSTD_freeDDict(ZSTD_DDict *cdict);
250 size_t ZSTD_freeCStream(ZSTD_CStream *zcs);
251 size_t ZSTD_freeDStream(ZSTD_DStream *zds);
252
253 #endif /* ZSTD_CCOMMON_H_MODULE */
254