1 /* zutil.c -- target dependent utility functions for the compression library
2 * Copyright (C) 1995-2005 Jean-loup Gailly.
3 * For conditions of distribution and use, see copyright notice in zlib.h
4 */
5
6 /* $Id: zutil.c,v 1.6 2005/10/11 21:31:11 rjs Exp $ */
7 /* @(#) $Id: zutil.c,v 1.6 2005/10/11 21:31:11 rjs Exp $ */
8
9 #include "zutil.h"
10
11 #ifndef NO_DUMMY_DECL
12 struct internal_state {int dummy;}; /* for buggy compilers */
13 #endif
14
15 const char * const z_errmsg[10] = {
16 "need dictionary", /* Z_NEED_DICT 2 */
17 "stream end", /* Z_STREAM_END 1 */
18 "", /* Z_OK 0 */
19 "file error", /* Z_ERRNO (-1) */
20 "stream error", /* Z_STREAM_ERROR (-2) */
21 "data error", /* Z_DATA_ERROR (-3) */
22 "insufficient memory", /* Z_MEM_ERROR (-4) */
23 "buffer error", /* Z_BUF_ERROR (-5) */
24 "incompatible version",/* Z_VERSION_ERROR (-6) */
25 ""};
26
27
zlibVersion()28 const char * ZEXPORT zlibVersion()
29 {
30 return ZLIB_VERSION;
31 }
32
zlibCompileFlags()33 uLong ZEXPORT zlibCompileFlags()
34 {
35 uLong flags;
36
37 flags = 0;
38 switch (sizeof(uInt)) {
39 case 2: break;
40 case 4: flags += 1; break;
41 case 8: flags += 2; break;
42 default: flags += 3;
43 }
44 switch (sizeof(uLong)) {
45 case 2: break;
46 case 4: flags += 1 << 2; break;
47 case 8: flags += 2 << 2; break;
48 default: flags += 3 << 2;
49 }
50 switch (sizeof(voidpf)) {
51 case 2: break;
52 case 4: flags += 1 << 4; break;
53 case 8: flags += 2 << 4; break;
54 default: flags += 3 << 4;
55 }
56 switch (sizeof(z_off_t)) {
57 case 2: break;
58 case 4: flags += 1 << 6; break;
59 case 8: flags += 2 << 6; break;
60 default: flags += 3 << 6;
61 }
62 #ifdef DEBUG
63 flags += 1 << 8;
64 #endif
65 #if defined(ASMV) || defined(ASMINF)
66 flags += 1 << 9;
67 #endif
68 #ifdef ZLIB_WINAPI
69 flags += 1 << 10;
70 #endif
71 #ifdef BUILDFIXED
72 flags += 1 << 12;
73 #endif
74 #ifdef DYNAMIC_CRC_TABLE
75 flags += 1 << 13;
76 #endif
77 #ifdef NO_GZCOMPRESS
78 flags += 1L << 16;
79 #endif
80 #ifdef NO_GZIP
81 flags += 1L << 17;
82 #endif
83 #ifdef PKZIP_BUG_WORKAROUND
84 flags += 1L << 20;
85 #endif
86 #ifdef FASTEST
87 flags += 1L << 21;
88 #endif
89 #ifdef STDC
90 # ifdef NO_vsnprintf
91 flags += 1L << 25;
92 # ifdef HAS_vsprintf_void
93 flags += 1L << 26;
94 # endif
95 # else
96 # ifdef HAS_vsnprintf_void
97 flags += 1L << 26;
98 # endif
99 # endif
100 #else
101 flags += 1L << 24;
102 # ifdef NO_snprintf
103 flags += 1L << 25;
104 # ifdef HAS_sprintf_void
105 flags += 1L << 26;
106 # endif
107 # else
108 # ifdef HAS_snprintf_void
109 flags += 1L << 26;
110 # endif
111 # endif
112 #endif
113 return flags;
114 }
115
116 #ifdef DEBUG
117
118 # ifndef verbose
119 # define verbose 0
120 # endif
121 int z_verbose = verbose;
122
z_error(char * m)123 void z_error (
124 char *m)
125 {
126 fprintf(stderr, "%s\n", m);
127 exit(1);
128 }
129 #endif
130
131 /* exported to allow conversion of error code to string for compress() and
132 * uncompress()
133 */
zError(int err)134 const char * ZEXPORT zError(
135 int err)
136 {
137 return ERR_MSG(err);
138 }
139
140 #if defined(_WIN32_WCE)
141 /* The Microsoft C Run-Time Library for Windows CE doesn't have
142 * errno. We define it as a global variable to simplify porting.
143 * Its value is always 0 and should not be used.
144 */
145 int errno = 0;
146 #endif
147
148 #ifndef HAVE_MEMCPY
149
zmemcpy(Bytef * dest,const Bytef * source,uInt len)150 void zmemcpy(
151 Bytef* dest,
152 const Bytef* source,
153 uInt len)
154 {
155 if (len == 0) return;
156 do {
157 *dest++ = *source++; /* ??? to be unrolled */
158 } while (--len != 0);
159 }
160
zmemcmp(const Bytef * s1,const Bytef * s2,uInt len)161 int zmemcmp(
162 const Bytef* s1,
163 const Bytef* s2,
164 uInt len)
165 {
166 uInt j;
167
168 for (j = 0; j < len; j++) {
169 if (s1[j] != s2[j]) return 2*(s1[j] > s2[j])-1;
170 }
171 return 0;
172 }
173
zmemzero(Bytef * dest,uInt len)174 void zmemzero(
175 Bytef* dest,
176 uInt len)
177 {
178 if (len == 0) return;
179 do {
180 *dest++ = 0; /* ??? to be unrolled */
181 } while (--len != 0);
182 }
183 #endif
184
185
186 #ifdef SYS16BIT
187
188 #ifdef __TURBOC__
189 /* Turbo C in 16-bit mode */
190
191 # define MY_ZCALLOC
192
193 /* Turbo C malloc() does not allow dynamic allocation of 64K bytes
194 * and farmalloc(64K) returns a pointer with an offset of 8, so we
195 * must fix the pointer. Warning: the pointer must be put back to its
196 * original form in order to free it, use zcfree().
197 */
198
199 #define MAX_PTR 10
200 /* 10*64K = 640K */
201
202 local int next_ptr = 0;
203
204 typedef struct ptr_table_s {
205 voidpf org_ptr;
206 voidpf new_ptr;
207 } ptr_table;
208
209 local ptr_table table[MAX_PTR];
210 /* This table is used to remember the original form of pointers
211 * to large buffers (64K). Such pointers are normalized with a zero offset.
212 * Since MSDOS is not a preemptive multitasking OS, this table is not
213 * protected from concurrent access. This hack doesn't work anyway on
214 * a protected system like OS/2. Use Microsoft C instead.
215 */
216
zcalloc(voidpf opaque,unsigned items,unsigned size)217 voidpf zcalloc (voidpf opaque, unsigned items, unsigned size)
218 {
219 voidpf buf = opaque; /* just to make some compilers happy */
220 ulg bsize = (ulg)items*size;
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 zcfree (voidpf opaque, voidpf ptr)
242 {
243 int n;
244 if (*(ush*)&ptr != 0) { /* object < 64K */
245 farfree(ptr);
246 return;
247 }
248 /* Find the original pointer */
249 for (n = 0; n < next_ptr; n++) {
250 if (ptr != table[n].new_ptr) continue;
251
252 farfree(table[n].org_ptr);
253 while (++n < next_ptr) {
254 table[n-1] = table[n];
255 }
256 next_ptr--;
257 return;
258 }
259 ptr = opaque; /* just to make some compilers happy */
260 Assert(0, "zcfree: ptr not found");
261 }
262
263 #endif /* __TURBOC__ */
264
265
266 #ifdef M_I86
267 /* Microsoft C in 16-bit mode */
268
269 # define MY_ZCALLOC
270
271 #if (!defined(_MSC_VER) || (_MSC_VER <= 600))
272 # define _halloc halloc
273 # define _hfree hfree
274 #endif
275
zcalloc(voidpf opaque,unsigned items,unsigned size)276 voidpf zcalloc (voidpf opaque, unsigned items, unsigned size)
277 {
278 if (opaque) opaque = 0; /* to make compiler happy */
279 return _halloc((long)items, size);
280 }
281
zcfree(voidpf opaque,voidpf ptr)282 void zcfree (voidpf opaque, voidpf ptr)
283 {
284 if (opaque) opaque = 0; /* to make compiler happy */
285 _hfree(ptr);
286 }
287
288 #endif /* M_I86 */
289
290 #endif /* SYS16BIT */
291
292
293 #ifndef MY_ZCALLOC /* Any system without a special alloc function */
294
295 #ifndef STDC
296 extern voidp malloc OF((uInt size));
297 extern voidp calloc OF((uInt items, uInt size));
298 extern void free OF((voidpf ptr));
299 #endif
300
zcalloc(voidpf opaque,unsigned items,unsigned size)301 voidpf zcalloc (
302 voidpf opaque,
303 unsigned items,
304 unsigned size)
305 {
306 if (opaque) items += size - size; /* make compiler happy */
307 return sizeof(uInt) > 2 ? (voidpf)malloc(items * size) :
308 (voidpf)calloc(items, size);
309 }
310
zcfree(voidpf opaque,voidpf ptr)311 void zcfree (
312 voidpf opaque,
313 voidpf ptr)
314 {
315 free(ptr);
316 if (opaque) return; /* make compiler happy */
317 }
318
319 #endif /* MY_ZCALLOC */
320