1 /* zutil.c -- target dependent utility functions for the compression library
2  * Copyright (C) 1995-2017 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()27 const char * ZEXPORT zlibVersion()
28 {
29     return ZLIB_VERSION;
30 }
31 
zlibCompileFlags()32 uLong ZEXPORT zlibCompileFlags()
33 {
34     uLong flags;
35 
36     flags = 0;
37     switch ((int)(sizeof(uInt))) {
38     case 2:     break;
39     case 4:     flags += 1;     break;
40     case 8:     flags += 2;     break;
41     default:    flags += 3;
42     }
43     switch ((int)(sizeof(uLong))) {
44     case 2:     break;
45     case 4:     flags += 1 << 2;        break;
46     case 8:     flags += 2 << 2;        break;
47     default:    flags += 3 << 2;
48     }
49     switch ((int)(sizeof(voidpf))) {
50     case 2:     break;
51     case 4:     flags += 1 << 4;        break;
52     case 8:     flags += 2 << 4;        break;
53     default:    flags += 3 << 4;
54     }
55     switch ((int)(sizeof(z_off_t))) {
56     case 2:     break;
57     case 4:     flags += 1 << 6;        break;
58     case 8:     flags += 2 << 6;        break;
59     default:    flags += 3 << 6;
60     }
61 #ifdef ZLIB_DEBUG
62     flags += 1 << 8;
63 #endif
64 #if defined(ASMV) || defined(ASMINF)
65     flags += 1 << 9;
66 #endif
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     flags += 1L << 25;
91 #    ifdef HAS_vsprintf_void
92     flags += 1L << 26;
93 #    endif
94 #  else
95 #    ifdef HAS_vsnprintf_void
96     flags += 1L << 26;
97 #    endif
98 #  endif
99 #else
100     flags += 1L << 24;
101 #  ifdef NO_snprintf
102     flags += 1L << 25;
103 #    ifdef HAS_sprintf_void
104     flags += 1L << 26;
105 #    endif
106 #  else
107 #    ifdef HAS_snprintf_void
108     flags += 1L << 26;
109 #    endif
110 #  endif
111 #endif
112     return flags;
113 }
114 
115 #ifdef ZLIB_DEBUG
116 #include <stdlib.h>
117 #  ifndef verbose
118 #    define verbose 0
119 #  endif
120 int ZLIB_INTERNAL z_verbose = verbose;
121 
z_error(m)122 void ZLIB_INTERNAL z_error (m)
123     char *m;
124 {
125     fprintf(stderr, "%s\n", m);
126     exit(1);
127 }
128 #endif
129 
130 /* exported to allow conversion of error code to string for compress() and
131  * uncompress()
132  */
zError(err)133 const char * ZEXPORT zError(err)
134     int err;
135 {
136     return ERR_MSG(err);
137 }
138 
139 #if defined(_WIN32_WCE)
140     /* The Microsoft C Run-Time Library for Windows CE doesn't have
141      * errno.  We define it as a global variable to simplify porting.
142      * Its value is always 0 and should not be used.
143      */
144     int errno = 0;
145 #endif
146 
147 #ifndef HAVE_MEMCPY
148 
zmemcpy(dest,source,len)149 void ZLIB_INTERNAL zmemcpy(dest, source, len)
150     Bytef* dest;
151     const Bytef* source;
152     uInt  len;
153 {
154     if (len == 0) return;
155     do {
156         *dest++ = *source++; /* ??? to be unrolled */
157     } while (--len != 0);
158 }
159 
zmemcmp(s1,s2,len)160 int ZLIB_INTERNAL zmemcmp(s1, s2, len)
161     const Bytef* s1;
162     const Bytef* s2;
163     uInt  len;
164 {
165     uInt j;
166 
167     for (j = 0; j < len; j++) {
168         if (s1[j] != s2[j]) return 2*(s1[j] > s2[j])-1;
169     }
170     return 0;
171 }
172 
zmemzero(dest,len)173 void ZLIB_INTERNAL zmemzero(dest, len)
174     Bytef* dest;
175     uInt  len;
176 {
177     if (len == 0) return;
178     do {
179         *dest++ = 0;  /* ??? to be unrolled */
180     } while (--len != 0);
181 }
182 #endif
183 
184 #ifndef Z_SOLO
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 ZLIB_INTERNAL zcalloc (voidpf opaque, unsigned items, unsigned size)
218 {
219     voidpf buf;
220     ulg bsize = (ulg)items*size;
221 
222     (void)opaque;
223 
224     /* If we allocate less than 65520 bytes, we assume that farmalloc
225      * will return a usable pointer which doesn't have to be normalized.
226      */
227     if (bsize < 65520L) {
228         buf = farmalloc(bsize);
229         if (*(ush*)&buf != 0) return buf;
230     } else {
231         buf = farmalloc(bsize + 16L);
232     }
233     if (buf == NULL || next_ptr >= MAX_PTR) return NULL;
234     table[next_ptr].org_ptr = buf;
235 
236     /* Normalize the pointer to seg:0 */
237     *((ush*)&buf+1) += ((ush)((uch*)buf-0) + 15) >> 4;
238     *(ush*)&buf = 0;
239     table[next_ptr++].new_ptr = buf;
240     return buf;
241 }
242 
zcfree(voidpf opaque,voidpf ptr)243 void ZLIB_INTERNAL zcfree (voidpf opaque, voidpf ptr)
244 {
245     int n;
246 
247     (void)opaque;
248 
249     if (*(ush*)&ptr != 0) { /* object < 64K */
250         farfree(ptr);
251         return;
252     }
253     /* Find the original pointer */
254     for (n = 0; n < next_ptr; n++) {
255         if (ptr != table[n].new_ptr) continue;
256 
257         farfree(table[n].org_ptr);
258         while (++n < next_ptr) {
259             table[n-1] = table[n];
260         }
261         next_ptr--;
262         return;
263     }
264     Assert(0, "zcfree: ptr not found");
265 }
266 
267 #endif /* __TURBOC__ */
268 
269 
270 #ifdef M_I86
271 /* Microsoft C in 16-bit mode */
272 
273 #  define MY_ZCALLOC
274 
275 #if (!defined(_MSC_VER) || (_MSC_VER <= 600))
276 #  define _halloc  halloc
277 #  define _hfree   hfree
278 #endif
279 
zcalloc(voidpf opaque,uInt items,uInt size)280 voidpf ZLIB_INTERNAL zcalloc (voidpf opaque, uInt items, uInt size)
281 {
282     (void)opaque;
283     return _halloc((long)items, size);
284 }
285 
zcfree(voidpf opaque,voidpf ptr)286 void ZLIB_INTERNAL zcfree (voidpf opaque, voidpf ptr)
287 {
288     (void)opaque;
289     _hfree(ptr);
290 }
291 
292 #endif /* M_I86 */
293 
294 #endif /* SYS16BIT */
295 
296 
297 #ifndef MY_ZCALLOC /* Any system without a special alloc function */
298 
299 #ifndef STDC
300 extern voidp  malloc OF((uInt size));
301 extern voidp  calloc OF((uInt items, uInt size));
302 extern void   free   OF((voidpf ptr));
303 #endif
304 
zcalloc(opaque,items,size)305 voidpf ZLIB_INTERNAL zcalloc (opaque, items, size)
306     voidpf opaque;
307     unsigned items;
308     unsigned size;
309 {
310     (void)opaque;
311     return sizeof(uInt) > 2 ? (voidpf)malloc(items * size) :
312                               (voidpf)calloc(items, size);
313 }
314 
zcfree(opaque,ptr)315 void ZLIB_INTERNAL zcfree (opaque, ptr)
316     voidpf opaque;
317     voidpf ptr;
318 {
319     (void)opaque;
320     free(ptr);
321 }
322 
323 #endif /* MY_ZCALLOC */
324 
325 #endif /* !Z_SOLO */
326