1 /* zutil.c -- target dependent utility functions for the compression library
2  * Copyright (C) 1995-2005, 2010, 2011, 2012 Jean-loup Gailly.
3  * For conditions of distribution and use, see copyright notice in zlib.h
4  */
5 
6 /* @(#) $Id: zutil.c,v 1.1.1.2 2002/03/11 21:53:27 tromey Exp $ */
7 
8 #include "zutil.h"
9 #ifndef Z_SOLO
10 #  include "gzguts.h"
11 #endif
12 
13 #ifndef NO_DUMMY_DECL
14 struct internal_state      {int dummy;}; /* for buggy compilers */
15 #endif
16 
17 z_const char * const z_errmsg[10] = {
18 "need dictionary",     /* Z_NEED_DICT       2  */
19 "stream end",          /* Z_STREAM_END      1  */
20 "",                    /* Z_OK              0  */
21 "file error",          /* Z_ERRNO         (-1) */
22 "stream error",        /* Z_STREAM_ERROR  (-2) */
23 "data error",          /* Z_DATA_ERROR    (-3) */
24 "insufficient memory", /* Z_MEM_ERROR     (-4) */
25 "buffer error",        /* Z_BUF_ERROR     (-5) */
26 "incompatible version",/* Z_VERSION_ERROR (-6) */
27 ""};
28 
29 
zlibVersion()30 const char * ZEXPORT zlibVersion()
31 {
32     return ZLIB_VERSION;
33 }
34 
zlibCompileFlags()35 uLong ZEXPORT zlibCompileFlags()
36 {
37     uLong flags;
38 
39     flags = 0;
40     switch ((int)(sizeof(uInt))) {
41     case 2:     break;
42     case 4:     flags += 1;     break;
43     case 8:     flags += 2;     break;
44     default:    flags += 3;
45     }
46     switch ((int)(sizeof(uLong))) {
47     case 2:     break;
48     case 4:     flags += 1 << 2;        break;
49     case 8:     flags += 2 << 2;        break;
50     default:    flags += 3 << 2;
51     }
52     switch ((int)(sizeof(voidpf))) {
53     case 2:     break;
54     case 4:     flags += 1 << 4;        break;
55     case 8:     flags += 2 << 4;        break;
56     default:    flags += 3 << 4;
57     }
58     switch ((int)(sizeof(z_off_t))) {
59     case 2:     break;
60     case 4:     flags += 1 << 6;        break;
61     case 8:     flags += 2 << 6;        break;
62     default:    flags += 3 << 6;
63     }
64 #ifdef DEBUG
65     flags += 1 << 8;
66 #endif
67 #if defined(ASMV) || defined(ASMINF)
68     flags += 1 << 9;
69 #endif
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 DEBUG
119 
120 #  ifndef verbose
121 #    define verbose 0
122 #  endif
123 int ZLIB_INTERNAL z_verbose = verbose;
124 
z_error(m)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  */
zError(err)136 const char * ZEXPORT zError(err)
137     int err;
138 {
139     return ERR_MSG(err);
140 }
141 
142 #if defined(_WIN32_WCE)
143     /* The 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 
zmemcpy(dest,source,len)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 
zmemcmp(s1,s2,len)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 
zmemzero(dest,len)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 
zcalloc(voidpf opaque,unsigned items,unsigned size)220 voidpf ZLIB_INTERNAL zcalloc (voidpf opaque, unsigned items, unsigned size)
221 {
222     voidpf buf = opaque; /* just to make some compilers happy */
223     ulg bsize = (ulg)items*size;
224 
225     /* If we allocate less than 65520 bytes, we assume that farmalloc
226      * will return a usable pointer which doesn't have to be normalized.
227      */
228     if (bsize < 65520L) {
229         buf = farmalloc(bsize);
230         if (*(ush*)&buf != 0) return buf;
231     } else {
232         buf = farmalloc(bsize + 16L);
233     }
234     if (buf == NULL || next_ptr >= MAX_PTR) return NULL;
235     table[next_ptr].org_ptr = buf;
236 
237     /* Normalize the pointer to seg:0 */
238     *((ush*)&buf+1) += ((ush)((uch*)buf-0) + 15) >> 4;
239     *(ush*)&buf = 0;
240     table[next_ptr++].new_ptr = buf;
241     return buf;
242 }
243 
zcfree(voidpf opaque,voidpf ptr)244 void ZLIB_INTERNAL zcfree (voidpf opaque, voidpf ptr)
245 {
246     int n;
247     if (*(ush*)&ptr != 0) { /* object < 64K */
248         farfree(ptr);
249         return;
250     }
251     /* Find the original pointer */
252     for (n = 0; n < next_ptr; n++) {
253         if (ptr != table[n].new_ptr) continue;
254 
255         farfree(table[n].org_ptr);
256         while (++n < next_ptr) {
257             table[n-1] = table[n];
258         }
259         next_ptr--;
260         return;
261     }
262     ptr = opaque; /* just to make some compilers happy */
263     Assert(0, "zcfree: ptr not found");
264 }
265 
266 #endif /* __TURBOC__ */
267 
268 
269 #ifdef M_I86
270 /* Microsoft C in 16-bit mode */
271 
272 #  define MY_ZCALLOC
273 
274 #if (!defined(_MSC_VER) || (_MSC_VER <= 600))
275 #  define _halloc  halloc
276 #  define _hfree   hfree
277 #endif
278 
zcalloc(voidpf opaque,uInt items,uInt size)279 voidpf ZLIB_INTERNAL zcalloc (voidpf opaque, uInt items, uInt size)
280 {
281     if (opaque) opaque = 0; /* to make compiler happy */
282     return _halloc((long)items, size);
283 }
284 
zcfree(voidpf opaque,voidpf ptr)285 void ZLIB_INTERNAL zcfree (voidpf opaque, voidpf ptr)
286 {
287     if (opaque) opaque = 0; /* to make compiler happy */
288     _hfree(ptr);
289 }
290 
291 #endif /* M_I86 */
292 
293 #endif /* SYS16BIT */
294 
295 
296 #ifndef MY_ZCALLOC /* Any system without a special alloc function */
297 
298 #ifndef STDC
299 extern voidp  malloc OF((uInt size));
300 extern voidp  calloc OF((uInt items, uInt size));
301 extern void   free   OF((voidpf ptr));
302 #endif
303 
zcalloc(opaque,items,size)304 voidpf ZLIB_INTERNAL zcalloc (opaque, items, size)
305     voidpf opaque;
306     unsigned items;
307     unsigned size;
308 {
309     if (opaque) items += size - size; /* make compiler happy */
310     return sizeof(uInt) > 2 ? (voidpf)malloc(items * size) :
311                               (voidpf)calloc(items, size);
312 }
313 
zcfree(opaque,ptr)314 void ZLIB_INTERNAL zcfree (opaque, ptr)
315     voidpf opaque;
316     voidpf ptr;
317 {
318     free(ptr);
319     if (opaque) return; /* make compiler happy */
320 }
321 
322 #endif /* MY_ZCALLOC */
323 
324 #endif /* !Z_SOLO */
325