xref: /openbsd-src/sys/lib/libz/zutil.c (revision 8550894424f8a4aa4aafb6cd57229dd6ed7cd9dd)
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 #include "zutil.h"
7 
8 #ifndef _KERNEL
9 #ifndef Z_SOLO
10 #  include "gzguts.h"
11 #endif
12 #endif
13 
14 z_const char * const z_errmsg[10] = {
15     (z_const char *)"need dictionary",     /* Z_NEED_DICT       2  */
16     (z_const char *)"stream end",          /* Z_STREAM_END      1  */
17     (z_const char *)"",                    /* Z_OK              0  */
18     (z_const char *)"file error",          /* Z_ERRNO         (-1) */
19     (z_const char *)"stream error",        /* Z_STREAM_ERROR  (-2) */
20     (z_const char *)"data error",          /* Z_DATA_ERROR    (-3) */
21     (z_const char *)"insufficient memory", /* Z_MEM_ERROR     (-4) */
22     (z_const char *)"buffer error",        /* Z_BUF_ERROR     (-5) */
23     (z_const char *)"incompatible version",/* Z_VERSION_ERROR (-6) */
24     (z_const char *)""
25 };
26 
27 
28 const char * ZEXPORT zlibVersion()
29 {
30     return ZLIB_VERSION;
31 }
32 
33 uLong ZEXPORT zlibCompileFlags()
34 {
35     uLong flags;
36 
37     flags = 0;
38     switch ((int)(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 ((int)(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 ((int)(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 ((int)(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 ZLIB_DEBUG
63     flags += 1 << 8;
64 #endif
65     /*
66 #if defined(ASMV) || defined(ASMINF)
67     flags += 1 << 9;
68 #endif
69      */
70 #ifdef ZLIB_WINAPI
71     flags += 1 << 10;
72 #endif
73 #ifdef BUILDFIXED
74     flags += 1 << 12;
75 #endif
76 #ifdef DYNAMIC_CRC_TABLE
77     flags += 1 << 13;
78 #endif
79 #ifdef NO_GZCOMPRESS
80     flags += 1L << 16;
81 #endif
82 #ifdef NO_GZIP
83     flags += 1L << 17;
84 #endif
85 #ifdef PKZIP_BUG_WORKAROUND
86     flags += 1L << 20;
87 #endif
88 #ifdef FASTEST
89     flags += 1L << 21;
90 #endif
91 #if defined(STDC) || defined(Z_HAVE_STDARG_H)
92 #  ifdef NO_vsnprintf
93     flags += 1L << 25;
94 #    ifdef HAS_vsprintf_void
95     flags += 1L << 26;
96 #    endif
97 #  else
98 #    ifdef HAS_vsnprintf_void
99     flags += 1L << 26;
100 #    endif
101 #  endif
102 #else
103     flags += 1L << 24;
104 #  ifdef NO_snprintf
105     flags += 1L << 25;
106 #    ifdef HAS_sprintf_void
107     flags += 1L << 26;
108 #    endif
109 #  else
110 #    ifdef HAS_snprintf_void
111     flags += 1L << 26;
112 #    endif
113 #  endif
114 #endif
115     return flags;
116 }
117 
118 #ifdef ZLIB_DEBUG
119 #include <stdlib.h>
120 #  ifndef verbose
121 #    define verbose 0
122 #  endif
123 int ZLIB_INTERNAL z_verbose = verbose;
124 
125 void ZLIB_INTERNAL z_error(m)
126     char *m;
127 {
128     fprintf(stderr, "%s\n", m);
129     exit(1);
130 }
131 #endif
132 
133 /* exported to allow conversion of error code to string for compress() and
134  * uncompress()
135  */
136 const char * ZEXPORT zError(err)
137     int err;
138 {
139     return ERR_MSG(err);
140 }
141 
142 #if defined(_WIN32_WCE) && _WIN32_WCE < 0x800
143     /* The older Microsoft C Run-Time Library for Windows CE doesn't have
144      * errno.  We define it as a global variable to simplify porting.
145      * Its value is always 0 and should not be used.
146      */
147     int errno = 0;
148 #endif
149 
150 #ifndef HAVE_MEMCPY
151 
152 void ZLIB_INTERNAL zmemcpy(dest, source, len)
153     Bytef* dest;
154     const Bytef* source;
155     uInt  len;
156 {
157     if (len == 0) return;
158     do {
159         *dest++ = *source++; /* ??? to be unrolled */
160     } while (--len != 0);
161 }
162 
163 int ZLIB_INTERNAL zmemcmp(s1, s2, len)
164     const Bytef* s1;
165     const Bytef* s2;
166     uInt  len;
167 {
168     uInt j;
169 
170     for (j = 0; j < len; j++) {
171         if (s1[j] != s2[j]) return 2*(s1[j] > s2[j])-1;
172     }
173     return 0;
174 }
175 
176 void ZLIB_INTERNAL zmemzero(dest, len)
177     Bytef* dest;
178     uInt  len;
179 {
180     if (len == 0) return;
181     do {
182         *dest++ = 0;  /* ??? to be unrolled */
183     } while (--len != 0);
184 }
185 #endif
186 
187 #ifndef Z_SOLO
188 
189 #ifdef SYS16BIT
190 
191 #ifdef __TURBOC__
192 /* Turbo C in 16-bit mode */
193 
194 #  define MY_ZCALLOC
195 
196 /* Turbo C malloc() does not allow dynamic allocation of 64K bytes
197  * and farmalloc(64K) returns a pointer with an offset of 8, so we
198  * must fix the pointer. Warning: the pointer must be put back to its
199  * original form in order to free it, use zcfree().
200  */
201 
202 #define MAX_PTR 10
203 /* 10*64K = 640K */
204 
205 local int next_ptr = 0;
206 
207 typedef struct ptr_table_s {
208     voidpf org_ptr;
209     voidpf new_ptr;
210 } ptr_table;
211 
212 local ptr_table table[MAX_PTR];
213 /* This table is used to remember the original form of pointers
214  * to large buffers (64K). Such pointers are normalized with a zero offset.
215  * Since MSDOS is not a preemptive multitasking OS, this table is not
216  * protected from concurrent access. This hack doesn't work anyway on
217  * a protected system like OS/2. Use Microsoft C instead.
218  */
219 
220 voidpf ZLIB_INTERNAL zcalloc(voidpf opaque, unsigned items, unsigned size)
221 {
222     voidpf buf;
223     ulg bsize = (ulg)items*size;
224 
225     (void)opaque;
226 
227     /* If we allocate less than 65520 bytes, we assume that farmalloc
228      * will return a usable pointer which doesn't have to be normalized.
229      */
230     if (bsize < 65520L) {
231         buf = farmalloc(bsize);
232         if (*(ush*)&buf != 0) return buf;
233     } else {
234         buf = farmalloc(bsize + 16L);
235     }
236     if (buf == NULL || next_ptr >= MAX_PTR) return NULL;
237     table[next_ptr].org_ptr = buf;
238 
239     /* Normalize the pointer to seg:0 */
240     *((ush*)&buf+1) += ((ush)((uch*)buf-0) + 15) >> 4;
241     *(ush*)&buf = 0;
242     table[next_ptr++].new_ptr = buf;
243     return buf;
244 }
245 
246 void ZLIB_INTERNAL zcfree(voidpf opaque, voidpf ptr)
247 {
248     int n;
249 
250     (void)opaque;
251 
252     if (*(ush*)&ptr != 0) { /* object < 64K */
253         farfree(ptr);
254         return;
255     }
256     /* Find the original pointer */
257     for (n = 0; n < next_ptr; n++) {
258         if (ptr != table[n].new_ptr) continue;
259 
260         farfree(table[n].org_ptr);
261         while (++n < next_ptr) {
262             table[n-1] = table[n];
263         }
264         next_ptr--;
265         return;
266     }
267     Assert(0, "zcfree: ptr not found");
268 }
269 
270 #endif /* __TURBOC__ */
271 
272 
273 #ifdef M_I86
274 /* Microsoft C in 16-bit mode */
275 
276 #  define MY_ZCALLOC
277 
278 #if (!defined(_MSC_VER) || (_MSC_VER <= 600))
279 #  define _halloc  halloc
280 #  define _hfree   hfree
281 #endif
282 
283 voidpf ZLIB_INTERNAL zcalloc(voidpf opaque, uInt items, uInt size)
284 {
285     (void)opaque;
286     return _halloc((long)items, size);
287 }
288 
289 void ZLIB_INTERNAL zcfree(voidpf opaque, voidpf ptr)
290 {
291     (void)opaque;
292     _hfree(ptr);
293 }
294 
295 #endif /* M_I86 */
296 
297 #endif /* SYS16BIT */
298 
299 
300 #ifndef MY_ZCALLOC /* Any system without a special alloc function */
301 
302 #ifndef STDC
303 extern voidp  malloc OF((uInt size));
304 extern voidp  calloc OF((uInt items, uInt size));
305 extern void   free   OF((voidpf ptr));
306 #endif
307 
308 voidpf ZLIB_INTERNAL zcalloc(opaque, items, size)
309     voidpf opaque;
310     unsigned items;
311     unsigned size;
312 {
313     (void)opaque;
314     if (items == 0 || size == 0)
315         return (NULL);
316     return reallocarray(NULL, items, size);
317 }
318 
319 void ZLIB_INTERNAL zcfree(opaque, ptr)
320     voidpf opaque;
321     voidpf ptr;
322 {
323     (void)opaque;
324     free(ptr);
325 }
326 
327 #endif /* MY_ZCALLOC */
328 
329 #endif /* !Z_SOLO */
330