xref: /freebsd/sys/contrib/zlib/zutil.c (revision 2008043f386721d58158e37e0d7e50df8095942d)
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 
27 const char * ZEXPORT zlibVersion(void) {
28     return ZLIB_VERSION;
29 }
30 
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     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 
122 void ZLIB_INTERNAL z_error(char *m) {
123     fprintf(stderr, "%s\n", m);
124     exit(1);
125 }
126 #endif
127 
128 /* exported to allow conversion of error code to string for compress() and
129  * uncompress()
130  */
131 const char * ZEXPORT zError(int err) {
132     return ERR_MSG(err);
133 }
134 
135 #if defined(_WIN32_WCE) && _WIN32_WCE < 0x800
136     /* The older Microsoft C Run-Time Library for Windows CE doesn't have
137      * errno.  We define it as a global variable to simplify porting.
138      * Its value is always 0 and should not be used.
139      */
140     int errno = 0;
141 #endif
142 
143 #ifndef HAVE_MEMCPY
144 
145 void ZLIB_INTERNAL zmemcpy(Bytef* dest, const Bytef* source, uInt len) {
146     if (len == 0) return;
147     do {
148         *dest++ = *source++; /* ??? to be unrolled */
149     } while (--len != 0);
150 }
151 
152 int ZLIB_INTERNAL zmemcmp(const Bytef* s1, const Bytef* s2, uInt len) {
153     uInt j;
154 
155     for (j = 0; j < len; j++) {
156         if (s1[j] != s2[j]) return 2*(s1[j] > s2[j])-1;
157     }
158     return 0;
159 }
160 
161 void ZLIB_INTERNAL zmemzero(Bytef* dest, uInt len) {
162     if (len == 0) return;
163     do {
164         *dest++ = 0;  /* ??? to be unrolled */
165     } while (--len != 0);
166 }
167 #endif
168 
169 #ifndef Z_SOLO
170 
171 #ifdef SYS16BIT
172 
173 #ifdef __TURBOC__
174 /* Turbo C in 16-bit mode */
175 
176 #  define MY_ZCALLOC
177 
178 /* Turbo C malloc() does not allow dynamic allocation of 64K bytes
179  * and farmalloc(64K) returns a pointer with an offset of 8, so we
180  * must fix the pointer. Warning: the pointer must be put back to its
181  * original form in order to free it, use zcfree().
182  */
183 
184 #define MAX_PTR 10
185 /* 10*64K = 640K */
186 
187 local int next_ptr = 0;
188 
189 typedef struct ptr_table_s {
190     voidpf org_ptr;
191     voidpf new_ptr;
192 } ptr_table;
193 
194 local ptr_table table[MAX_PTR];
195 /* This table is used to remember the original form of pointers
196  * to large buffers (64K). Such pointers are normalized with a zero offset.
197  * Since MSDOS is not a preemptive multitasking OS, this table is not
198  * protected from concurrent access. This hack doesn't work anyway on
199  * a protected system like OS/2. Use Microsoft C instead.
200  */
201 
202 voidpf ZLIB_INTERNAL zcalloc(voidpf opaque, unsigned items, unsigned size) {
203     voidpf buf;
204     ulg bsize = (ulg)items*size;
205 
206     (void)opaque;
207 
208     /* If we allocate less than 65520 bytes, we assume that farmalloc
209      * will return a usable pointer which doesn't have to be normalized.
210      */
211     if (bsize < 65520L) {
212         buf = farmalloc(bsize);
213         if (*(ush*)&buf != 0) return buf;
214     } else {
215         buf = farmalloc(bsize + 16L);
216     }
217     if (buf == NULL || next_ptr >= MAX_PTR) return NULL;
218     table[next_ptr].org_ptr = buf;
219 
220     /* Normalize the pointer to seg:0 */
221     *((ush*)&buf+1) += ((ush)((uch*)buf-0) + 15) >> 4;
222     *(ush*)&buf = 0;
223     table[next_ptr++].new_ptr = buf;
224     return buf;
225 }
226 
227 void ZLIB_INTERNAL zcfree(voidpf opaque, voidpf ptr) {
228     int n;
229 
230     (void)opaque;
231 
232     if (*(ush*)&ptr != 0) { /* object < 64K */
233         farfree(ptr);
234         return;
235     }
236     /* Find the original pointer */
237     for (n = 0; n < next_ptr; n++) {
238         if (ptr != table[n].new_ptr) continue;
239 
240         farfree(table[n].org_ptr);
241         while (++n < next_ptr) {
242             table[n-1] = table[n];
243         }
244         next_ptr--;
245         return;
246     }
247     Assert(0, "zcfree: ptr not found");
248 }
249 
250 #endif /* __TURBOC__ */
251 
252 
253 #ifdef M_I86
254 /* Microsoft C in 16-bit mode */
255 
256 #  define MY_ZCALLOC
257 
258 #if (!defined(_MSC_VER) || (_MSC_VER <= 600))
259 #  define _halloc  halloc
260 #  define _hfree   hfree
261 #endif
262 
263 voidpf ZLIB_INTERNAL zcalloc(voidpf opaque, uInt items, uInt size) {
264     (void)opaque;
265     return _halloc((long)items, size);
266 }
267 
268 void ZLIB_INTERNAL zcfree(voidpf opaque, voidpf ptr) {
269     (void)opaque;
270     _hfree(ptr);
271 }
272 
273 #endif /* M_I86 */
274 
275 #endif /* SYS16BIT */
276 
277 
278 #ifndef MY_ZCALLOC /* Any system without a special alloc function */
279 
280 #ifndef STDC
281 extern voidp malloc(uInt size);
282 extern voidp calloc(uInt items, uInt size);
283 extern void free(voidpf ptr);
284 #endif
285 
286 voidpf ZLIB_INTERNAL zcalloc(voidpf opaque, unsigned items, unsigned size) {
287     (void)opaque;
288     return sizeof(uInt) > 2 ? (voidpf)malloc(items * size) :
289                               (voidpf)calloc(items, size);
290 }
291 
292 void ZLIB_INTERNAL zcfree(voidpf opaque, voidpf ptr) {
293     (void)opaque;
294     free(ptr);
295 }
296 
297 #endif /* MY_ZCALLOC */
298 
299 #endif /* !Z_SOLO */
300