1 /* zutil.h -- internal interface and configuration of the compression library
2 * Copyright (C) 1995-2026 Jean-loup Gailly, Mark Adler
3 * For conditions of distribution and use, see copyright notice in zlib.h
4 */
5
6 /* WARNING: this file should *not* be used by applications. It is
7 part of the implementation of the compression library and is
8 subject to change. Applications should only use zlib.h.
9 */
10
11 /* @(#) $Id$ */
12
13 #ifndef ZUTIL_H
14 #define ZUTIL_H
15
16 #ifdef HAVE_HIDDEN
17 # define ZLIB_INTERNAL __attribute__((visibility ("hidden")))
18 #else
19 # define ZLIB_INTERNAL
20 #endif
21
22 #include "zlib.h"
23
24 #if defined(STDC) && !defined(Z_SOLO)
25 # if !(defined(_WIN32_WCE) && defined(_MSC_VER))
26 # include <stddef.h>
27 # endif
28 # include <string.h>
29 # include <stdlib.h>
30 #endif
31
32 #ifndef local
33 # define local static
34 #endif
35 /* since "static" is used to mean two completely different things in C, we
36 define "local" for the non-static meaning of "static", for readability
37 (compile with -Dlocal if your debugger can't find static symbols) */
38
39 extern const char deflate_copyright[];
40 extern const char inflate_copyright[];
41 extern const char inflate9_copyright[];
42
43 typedef unsigned char uch;
44 typedef uch FAR uchf;
45 typedef unsigned short ush;
46 typedef ush FAR ushf;
47 typedef unsigned long ulg;
48
49 #if !defined(Z_U8) && !defined(Z_SOLO) && defined(STDC)
50 # include <limits.h>
51 # if (ULONG_MAX == 0xffffffffffffffff)
52 # define Z_U8 unsigned long
53 # elif (ULLONG_MAX == 0xffffffffffffffff)
54 # define Z_U8 unsigned long long
55 # elif (ULONG_LONG_MAX == 0xffffffffffffffff)
56 # define Z_U8 unsigned long long
57 # elif (UINT_MAX == 0xffffffffffffffff)
58 # define Z_U8 unsigned
59 # endif
60 #endif
61
62 extern z_const char * const z_errmsg[10]; /* indexed by 2-zlib_error */
63 /* (size given to avoid silly warnings with Visual C++) */
64
65 #define ERR_MSG(err) z_errmsg[(err) < -6 || (err) > 2 ? 9 : 2 - (err)]
66
67 #define ERR_RETURN(strm,err) \
68 return (strm->msg = ERR_MSG(err), (err))
69 /* To be used only when the state is known to be valid */
70
71 /* common constants */
72 #if MAX_WBITS < 9 || MAX_WBITS > 15
73 # error MAX_WBITS must be in 9..15
74 #endif
75 #ifndef DEF_WBITS
76 # define DEF_WBITS MAX_WBITS
77 #endif
78 /* default windowBits for decompression. MAX_WBITS is for compression only */
79
80 #if MAX_MEM_LEVEL >= 8
81 # define DEF_MEM_LEVEL 8
82 #else
83 # define DEF_MEM_LEVEL MAX_MEM_LEVEL
84 #endif
85 /* default memLevel */
86
87 #define STORED_BLOCK 0
88 #define STATIC_TREES 1
89 #define DYN_TREES 2
90 /* The three kinds of block type */
91
92 #define MIN_MATCH 3
93 #define MAX_MATCH 258
94 /* The minimum and maximum match lengths */
95
96 #define PRESET_DICT 0x20 /* preset dictionary flag in zlib header */
97
98 /* target dependencies */
99
100 #if defined(MSDOS) || (defined(WINDOWS) && !defined(WIN32))
101 # define OS_CODE 0x00
102 # ifndef Z_SOLO
103 # if defined(__TURBOC__) || defined(__BORLANDC__)
104 # if (__STDC__ == 1) && (defined(__LARGE__) || defined(__COMPACT__))
105 /* Allow compilation with ANSI keywords only enabled */
106 void _Cdecl farfree( void *block );
107 void *_Cdecl farmalloc( unsigned long nbytes );
108 # else
109 # include <alloc.h>
110 # endif
111 # else /* MSC or DJGPP */
112 # include <malloc.h>
113 # endif
114 # endif
115 #endif
116
117 #ifdef AMIGA
118 # define OS_CODE 1
119 #endif
120
121 #if defined(VAXC) || defined(VMS)
122 # define OS_CODE 2
123 # define F_OPEN(name, mode) \
124 fopen((name), (mode), "mbc=60", "ctx=stm", "rfm=fix", "mrs=512")
125 #endif
126
127 #ifdef __370__
128 # if __TARGET_LIB__ < 0x20000000
129 # define OS_CODE 4
130 # elif __TARGET_LIB__ < 0x40000000
131 # define OS_CODE 11
132 # else
133 # define OS_CODE 8
134 # endif
135 #endif
136
137 #if defined(ATARI) || defined(atarist)
138 # define OS_CODE 5
139 #endif
140
141 #ifdef OS2
142 # define OS_CODE 6
143 # if defined(M_I86) && !defined(Z_SOLO)
144 # include <malloc.h>
145 # endif
146 #endif
147
148 #if defined(MACOS)
149 # define OS_CODE 7
150 #endif
151
152 #if defined(__acorn) || defined(__riscos)
153 # define OS_CODE 13
154 #endif
155
156 #if defined(WIN32) && !defined(__CYGWIN__)
157 # define OS_CODE 10
158 #endif
159
160 #ifdef _BEOS_
161 # define OS_CODE 16
162 #endif
163
164 #ifdef __TOS_OS400__
165 # define OS_CODE 18
166 #endif
167
168 #ifdef __APPLE__
169 # define OS_CODE 19
170 #endif
171
172 #if defined(__BORLANDC__) && !defined(MSDOS)
173 #pragma warn -8004
174 #pragma warn -8008
175 #pragma warn -8066
176 #endif
177
178 /* provide prototypes for these when building zlib without LFS */
179 #ifndef Z_LARGE64
180 ZEXTERN uLong ZEXPORT adler32_combine64(uLong, uLong, z_off64_t);
181 ZEXTERN uLong ZEXPORT crc32_combine64(uLong, uLong, z_off64_t);
182 ZEXTERN uLong ZEXPORT crc32_combine_gen64(z_off64_t);
183 #endif
184
185 /* common defaults */
186
187 #ifndef OS_CODE
188 # define OS_CODE 3 /* assume Unix */
189 #endif
190
191 #ifndef F_OPEN
192 # define F_OPEN(name, mode) fopen((name), (mode))
193 #endif
194
195 /* functions */
196
197 #if defined(pyr) || defined(Z_SOLO)
198 # define NO_MEMCPY
199 #endif
200 #if defined(SMALL_MEDIUM) && !defined(_MSC_VER) && !defined(__SC__)
201 /* Use our own functions for small and medium model with MSC <= 5.0.
202 * You may have to use the same strategy for Borland C (untested).
203 * The __SC__ check is for Symantec.
204 */
205 # define NO_MEMCPY
206 #endif
207 #if defined(STDC) && !defined(HAVE_MEMCPY) && !defined(NO_MEMCPY)
208 # define HAVE_MEMCPY
209 #endif
210 #ifdef HAVE_MEMCPY
211 # ifdef SMALL_MEDIUM /* MSDOS small or medium model */
212 # define zmemcpy _fmemcpy
213 # define zmemcmp _fmemcmp
214 # define zmemzero(dest, len) _fmemset(dest, 0, len)
215 # else
216 # define zmemcpy memcpy
217 # define zmemcmp memcmp
218 # define zmemzero(dest, len) memset(dest, 0, len)
219 # endif
220 #else
221 void ZLIB_INTERNAL zmemcpy(void FAR *, const void FAR *, z_size_t);
222 int ZLIB_INTERNAL zmemcmp(const void FAR *, const void FAR *, z_size_t);
223 void ZLIB_INTERNAL zmemzero(void FAR *, z_size_t);
224 #endif
225
226 /* Diagnostic functions */
227 #ifdef ZLIB_DEBUG
228 # include <stdio.h>
229 extern int ZLIB_INTERNAL z_verbose;
230 extern void ZLIB_INTERNAL z_error(char *m);
231 # define Assert(cond,msg) {if(!(cond)) z_error(msg);}
232 # define Trace(x) {if (z_verbose>=0) fprintf x ;}
233 # define Tracev(x) {if (z_verbose>0) fprintf x ;}
234 # define Tracevv(x) {if (z_verbose>1) fprintf x ;}
235 # define Tracec(c,x) {if (z_verbose>0 && (c)) fprintf x ;}
236 # define Tracecv(c,x) {if (z_verbose>1 && (c)) fprintf x ;}
237 #else
238 # define Assert(cond,msg)
239 # define Trace(x)
240 # define Tracev(x)
241 # define Tracevv(x)
242 # define Tracec(c,x)
243 # define Tracecv(c,x)
244 #endif
245
246 #if !defined(Z_SOLO) || defined(_KERNEL)
247 voidpf ZLIB_INTERNAL zcalloc(voidpf opaque, unsigned items,
248 unsigned size);
249 void ZLIB_INTERNAL zcfree(voidpf opaque, voidpf ptr);
250 #endif
251
252 #define ZALLOC(strm, items, size) \
253 (*((strm)->zalloc))((strm)->opaque, (items), (size))
254 #define ZFREE(strm, addr) (*((strm)->zfree))((strm)->opaque, (voidpf)(addr))
255 #define TRY_FREE(s, p) {if (p) ZFREE(s, p);}
256
257 /* Reverse the bytes in a 32-bit value */
258 #define ZSWAP32(q) ((((q) >> 24) & 0xff) + (((q) >> 8) & 0xff00) + \
259 (((q) & 0xff00) << 8) + (((q) & 0xff) << 24))
260
261 #ifdef Z_ONCE
262 /*
263 Create a local z_once() function depending on the availability of atomics.
264 */
265
266 /* Check for the availability of atomics. */
267 #if defined(__STDC__) && __STDC_VERSION__ >= 201112L && \
268 !defined(__STDC_NO_ATOMICS__)
269
270 #include <stdatomic.h>
271 typedef struct {
272 atomic_flag begun;
273 atomic_int done;
274 } z_once_t;
275 #define Z_ONCE_INIT {ATOMIC_FLAG_INIT, 0}
276
277 /*
278 Run the provided init() function exactly once, even if multiple threads
279 invoke once() at the same time. The state must be a once_t initialized with
280 Z_ONCE_INIT.
281 */
z_once(z_once_t * state,void (* init)(void))282 local void z_once(z_once_t *state, void (*init)(void)) {
283 if (!atomic_load(&state->done)) {
284 if (atomic_flag_test_and_set(&state->begun))
285 while (!atomic_load(&state->done))
286 ;
287 else {
288 init();
289 atomic_store(&state->done, 1);
290 }
291 }
292 }
293
294 #else /* no atomics */
295
296 #warning zlib not thread-safe
297
298 typedef struct z_once_s {
299 volatile int begun;
300 volatile int done;
301 } z_once_t;
302 #define Z_ONCE_INIT {0, 0}
303
304 /* Test and set. Alas, not atomic, but tries to limit the period of
305 vulnerability. */
test_and_set(int volatile * flag)306 local int test_and_set(int volatile *flag) {
307 int was;
308
309 was = *flag;
310 *flag = 1;
311 return was;
312 }
313
314 /* Run the provided init() function once. This is not thread-safe. */
z_once(z_once_t * state,void (* init)(void))315 local void z_once(z_once_t *state, void (*init)(void)) {
316 if (!state->done) {
317 if (test_and_set(&state->begun))
318 while (!state->done)
319 ;
320 else {
321 init();
322 state->done = 1;
323 }
324 }
325 }
326
327 #endif /* ?atomics */
328
329 #endif /* Z_ONCE */
330
331 #endif /* ZUTIL_H */
332