1 /* zutil.c -- target dependent utility functions for the compression library
2 * Copyright (C) 1995-2026 Jean-loup Gailly
3 * For conditions of distribution and use, see copyright notice in zlib.h
4 */
5
6 /* @(#) $Id$ */
7
8 #include "zutil.h"
9 #ifndef Z_SOLO
10 # include "gzguts.h"
11 #endif
12
13 z_const char * const z_errmsg[10] = {
14 (z_const char *)"need dictionary", /* Z_NEED_DICT 2 */
15 (z_const char *)"stream end", /* Z_STREAM_END 1 */
16 (z_const char *)"", /* Z_OK 0 */
17 (z_const char *)"file error", /* Z_ERRNO (-1) */
18 (z_const char *)"stream error", /* Z_STREAM_ERROR (-2) */
19 (z_const char *)"data error", /* Z_DATA_ERROR (-3) */
20 (z_const char *)"insufficient memory", /* Z_MEM_ERROR (-4) */
21 (z_const char *)"buffer error", /* Z_BUF_ERROR (-5) */
22 (z_const char *)"incompatible version",/* Z_VERSION_ERROR (-6) */
23 (z_const char *)""
24 };
25
26
zlibVersion(void)27 const char * ZEXPORT zlibVersion(void) {
28 return ZLIB_VERSION;
29 }
30
zlibCompileFlags(void)31 uLong ZEXPORT zlibCompileFlags(void) {
32 uLong flags;
33
34 flags = 0;
35 switch ((int)(sizeof(uInt))) {
36 case 2: break;
37 case 4: flags += 1; break;
38 case 8: flags += 2; break;
39 default: flags += 3;
40 }
41 switch ((int)(sizeof(uLong))) {
42 case 2: break;
43 case 4: flags += 1 << 2; break;
44 case 8: flags += 2 << 2; break;
45 default: flags += 3 << 2;
46 }
47 switch ((int)(sizeof(voidpf))) {
48 case 2: break;
49 case 4: flags += 1 << 4; break;
50 case 8: flags += 2 << 4; break;
51 default: flags += 3 << 4;
52 }
53 switch ((int)(sizeof(z_off_t))) {
54 case 2: break;
55 case 4: flags += 1 << 6; break;
56 case 8: flags += 2 << 6; break;
57 default: flags += 3 << 6;
58 }
59 #ifdef ZLIB_DEBUG
60 flags += 1 << 8;
61 #endif
62 /*
63 #if defined(ASMV) || defined(ASMINF)
64 flags += 1 << 9;
65 #endif
66 */
67 #ifdef ZLIB_WINAPI
68 flags += 1 << 10;
69 #endif
70 #ifdef BUILDFIXED
71 flags += 1 << 12;
72 #endif
73 #ifdef DYNAMIC_CRC_TABLE
74 flags += 1 << 13;
75 #endif
76 #ifdef NO_GZCOMPRESS
77 flags += 1L << 16;
78 #endif
79 #ifdef NO_GZIP
80 flags += 1L << 17;
81 #endif
82 #ifdef PKZIP_BUG_WORKAROUND
83 flags += 1L << 20;
84 #endif
85 #ifdef FASTEST
86 flags += 1L << 21;
87 #endif
88 #if defined(STDC) || defined(Z_HAVE_STDARG_H)
89 # ifdef NO_vsnprintf
90 # ifdef ZLIB_INSECURE
91 flags += 1L << 25;
92 # else
93 flags += 1L << 27;
94 # endif
95 # ifdef HAS_vsprintf_void
96 flags += 1L << 26;
97 # endif
98 # else
99 # ifdef HAS_vsnprintf_void
100 flags += 1L << 26;
101 # endif
102 # endif
103 #else
104 flags += 1L << 24;
105 # ifdef NO_snprintf
106 # ifdef ZLIB_INSECURE
107 flags += 1L << 25;
108 # else
109 flags += 1L << 27;
110 # endif
111 # ifdef HAS_sprintf_void
112 flags += 1L << 26;
113 # endif
114 # else
115 # ifdef HAS_snprintf_void
116 flags += 1L << 26;
117 # endif
118 # endif
119 #endif
120 return flags;
121 }
122
123 #ifdef ZLIB_DEBUG
124 #include <stdlib.h>
125 # ifndef verbose
126 # define verbose 0
127 # endif
128 int ZLIB_INTERNAL z_verbose = verbose;
129
z_error(char * m)130 void ZLIB_INTERNAL z_error(char *m) {
131 fprintf(stderr, "%s\n", m);
132 exit(1);
133 }
134 #endif
135
136 /* exported to allow conversion of error code to string for compress() and
137 * uncompress()
138 */
zError(int err)139 const char * ZEXPORT zError(int err) {
140 return ERR_MSG(err);
141 }
142
143 #if defined(_WIN32_WCE) && _WIN32_WCE < 0x800
144 /* The older Microsoft C Run-Time Library for Windows CE doesn't have
145 * errno. We define it as a global variable to simplify porting.
146 * Its value is always 0 and should not be used.
147 */
148 int errno = 0;
149 #endif
150
151 #ifndef HAVE_MEMCPY
152
zmemcpy(void FAR * dst,const void FAR * src,z_size_t n)153 void ZLIB_INTERNAL zmemcpy(void FAR *dst, const void FAR *src, z_size_t n) {
154 uchf *p = dst;
155 const uchf *q = src;
156 while (n) {
157 *p++ = *q++;
158 n--;
159 }
160 }
161
zmemcmp(const void FAR * s1,const void FAR * s2,z_size_t n)162 int ZLIB_INTERNAL zmemcmp(const void FAR *s1, const void FAR *s2, z_size_t n) {
163 const uchf *p = s1, *q = s2;
164 while (n) {
165 if (*p++ != *q++)
166 return (int)p[-1] - (int)q[-1];
167 n--;
168 }
169 return 0;
170 }
171
zmemzero(void FAR * b,z_size_t len)172 void ZLIB_INTERNAL zmemzero(void FAR *b, z_size_t len) {
173 uchf *p = b;
174 if (len == 0) return;
175 while (len) {
176 *p++ = 0;
177 len--;
178 }
179 }
180
181 #endif
182
183 #ifndef Z_SOLO
184
185 #ifdef SYS16BIT
186
187 #ifdef __TURBOC__
188 /* Turbo C in 16-bit mode */
189
190 # define MY_ZCALLOC
191
192 /* Turbo C malloc() does not allow dynamic allocation of 64K bytes
193 * and farmalloc(64K) returns a pointer with an offset of 8, so we
194 * must fix the pointer. Warning: the pointer must be put back to its
195 * original form in order to free it, use zcfree().
196 */
197
198 #define MAX_PTR 10
199 /* 10*64K = 640K */
200
201 local int next_ptr = 0;
202
203 typedef struct ptr_table_s {
204 voidpf org_ptr;
205 voidpf new_ptr;
206 } ptr_table;
207
208 local ptr_table table[MAX_PTR];
209 /* This table is used to remember the original form of pointers
210 * to large buffers (64K). Such pointers are normalized with a zero offset.
211 * Since MSDOS is not a preemptive multitasking OS, this table is not
212 * protected from concurrent access. This hack doesn't work anyway on
213 * a protected system like OS/2. Use Microsoft C instead.
214 */
215
zcalloc(voidpf opaque,unsigned items,unsigned size)216 voidpf ZLIB_INTERNAL zcalloc(voidpf opaque, unsigned items, unsigned size) {
217 voidpf buf;
218 ulg bsize = (ulg)items*size;
219
220 (void)opaque;
221
222 /* If we allocate less than 65520 bytes, we assume that farmalloc
223 * will return a usable pointer which doesn't have to be normalized.
224 */
225 if (bsize < 65520L) {
226 buf = farmalloc(bsize);
227 if (*(ush*)&buf != 0) return buf;
228 } else {
229 buf = farmalloc(bsize + 16L);
230 }
231 if (buf == NULL || next_ptr >= MAX_PTR) return NULL;
232 table[next_ptr].org_ptr = buf;
233
234 /* Normalize the pointer to seg:0 */
235 *((ush*)&buf+1) += ((ush)((uch*)buf-0) + 15) >> 4;
236 *(ush*)&buf = 0;
237 table[next_ptr++].new_ptr = buf;
238 return buf;
239 }
240
zcfree(voidpf opaque,voidpf ptr)241 void ZLIB_INTERNAL zcfree(voidpf opaque, voidpf ptr) {
242 int n;
243
244 (void)opaque;
245
246 if (*(ush*)&ptr != 0) { /* object < 64K */
247 farfree(ptr);
248 return;
249 }
250 /* Find the original pointer */
251 for (n = 0; n < next_ptr; n++) {
252 if (ptr != table[n].new_ptr) continue;
253
254 farfree(table[n].org_ptr);
255 while (++n < next_ptr) {
256 table[n-1] = table[n];
257 }
258 next_ptr--;
259 return;
260 }
261 Assert(0, "zcfree: ptr not found");
262 }
263
264 #endif /* __TURBOC__ */
265
266
267 #ifdef M_I86
268 /* Microsoft C in 16-bit mode */
269
270 # define MY_ZCALLOC
271
272 #if (!defined(_MSC_VER) || (_MSC_VER <= 600))
273 # define _halloc halloc
274 # define _hfree hfree
275 #endif
276
zcalloc(voidpf opaque,uInt items,uInt size)277 voidpf ZLIB_INTERNAL zcalloc(voidpf opaque, uInt items, uInt size) {
278 (void)opaque;
279 return _halloc((long)items, size);
280 }
281
zcfree(voidpf opaque,voidpf ptr)282 void ZLIB_INTERNAL zcfree(voidpf opaque, voidpf ptr) {
283 (void)opaque;
284 _hfree(ptr);
285 }
286
287 #endif /* M_I86 */
288
289 #endif /* SYS16BIT */
290
291
292 #ifndef MY_ZCALLOC /* Any system without a special alloc function */
293
294 #ifndef STDC
295 extern voidp malloc(uInt size);
296 extern voidp calloc(uInt items, uInt size);
297 extern void free(voidpf ptr);
298 #endif
299
zcalloc(voidpf opaque,unsigned items,unsigned size)300 voidpf ZLIB_INTERNAL zcalloc(voidpf opaque, unsigned items, unsigned size) {
301 (void)opaque;
302 return sizeof(uInt) > 2 ? (voidpf)malloc(items * size) :
303 (voidpf)calloc(items, size);
304 }
305
zcfree(voidpf opaque,voidpf ptr)306 void ZLIB_INTERNAL zcfree(voidpf opaque, voidpf ptr) {
307 (void)opaque;
308 free(ptr);
309 }
310
311 #endif /* MY_ZCALLOC */
312
313 #endif /* !Z_SOLO */
314