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/* @(#) $Id$ */
7
8#include "zutil.h"
9
10#ifndef NO_DUMMY_DECL
11struct internal_state      {int dummy;}; /* for buggy compilers */
12#endif
13
14const char * const z_errmsg[10] = {
15"need dictionary",     /* Z_NEED_DICT       2  */
16"stream end",          /* Z_STREAM_END      1  */
17"",                    /* Z_OK              0  */
18"file error",          /* Z_ERRNO         (-1) */
19"stream error",        /* Z_STREAM_ERROR  (-2) */
20"data error",          /* Z_DATA_ERROR    (-3) */
21"insufficient memory", /* Z_MEM_ERROR     (-4) */
22"buffer error",        /* Z_BUF_ERROR     (-5) */
23"incompatible version",/* Z_VERSION_ERROR (-6) */
24""};
25
26
27const char * ZEXPORT zlibVersion()
28{
29    return ZLIB_VERSION;
30}
31
32uLong ZEXPORT zlibCompileFlags()
33{
34    uLong flags;
35
36    flags = 0;
37    switch (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 (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 (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 (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 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#ifdef STDC
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 DEBUG
116
117#  ifndef verbose
118#    define verbose 0
119#  endif
120int z_verbose = verbose;
121
122void 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 */
133const 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
149void 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
160int 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
173void 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
185#ifdef SYS16BIT
186
187#ifdef __TURBOC__
188/* Turbo C in 16-bit mode */
189
190#  define MY_ZCALLOC
191
192/* Turbo C malloc() does not allow dynamic allocation of 64K bytes
193 * and farmalloc(64K) returns a pointer with an offset of 8, so we
194 * must fix the pointer. Warning: the pointer must be put back to its
195 * original form in order to free it, use zcfree().
196 */
197
198#define MAX_PTR 10
199/* 10*64K = 640K */
200
201local int next_ptr = 0;
202
203typedef struct ptr_table_s {
204    voidpf org_ptr;
205    voidpf new_ptr;
206} ptr_table;
207
208local ptr_table table[MAX_PTR];
209/* This table is used to remember the original form of pointers
210 * to large buffers (64K). Such pointers are normalized with a zero offset.
211 * Since MSDOS is not a preemptive multitasking OS, this table is not
212 * protected from concurrent access. This hack doesn't work anyway on
213 * a protected system like OS/2. Use Microsoft C instead.
214 */
215
216voidpf zcalloc (voidpf opaque, unsigned items, unsigned size)
217{
218    voidpf buf = opaque; /* just to make some compilers happy */
219    ulg bsize = (ulg)items*size;
220
221    /* If we allocate less than 65520 bytes, we assume that farmalloc
222     * will return a usable pointer which doesn't have to be normalized.
223     */
224    if (bsize < 65520L) {
225        buf = farmalloc(bsize);
226        if (*(ush*)&buf != 0) return buf;
227    } else {
228        buf = farmalloc(bsize + 16L);
229    }
230    if (buf == NULL || next_ptr >= MAX_PTR) return NULL;
231    table[next_ptr].org_ptr = buf;
232
233    /* Normalize the pointer to seg:0 */
234    *((ush*)&buf+1) += ((ush)((uch*)buf-0) + 15) >> 4;
235    *(ush*)&buf = 0;
236    table[next_ptr++].new_ptr = buf;
237    return buf;
238}
239
240void  zcfree (voidpf opaque, voidpf ptr)
241{
242    int n;
243    if (*(ush*)&ptr != 0) { /* object < 64K */
244        farfree(ptr);
245        return;
246    }
247    /* Find the original pointer */
248    for (n = 0; n < next_ptr; n++) {
249        if (ptr != table[n].new_ptr) continue;
250
251        farfree(table[n].org_ptr);
252        while (++n < next_ptr) {
253            table[n-1] = table[n];
254        }
255        next_ptr--;
256        return;
257    }
258    ptr = opaque; /* just to make some compilers happy */
259    Assert(0, "zcfree: ptr not found");
260}
261
262#endif /* __TURBOC__ */
263
264
265#ifdef M_I86
266/* Microsoft C in 16-bit mode */
267
268#  define MY_ZCALLOC
269
270#if (!defined(_MSC_VER) || (_MSC_VER <= 600))
271#  define _halloc  halloc
272#  define _hfree   hfree
273#endif
274
275voidpf zcalloc (voidpf opaque, unsigned items, unsigned size)
276{
277    if (opaque) opaque = 0; /* to make compiler happy */
278    return _halloc((long)items, size);
279}
280
281void  zcfree (voidpf opaque, voidpf ptr)
282{
283    if (opaque) opaque = 0; /* to make compiler happy */
284    _hfree(ptr);
285}
286
287#endif /* M_I86 */
288
289#endif /* SYS16BIT */
290
291
292#ifndef MY_ZCALLOC /* Any system without a special alloc function */
293
294#ifndef STDC
295extern voidp  malloc OF((uInt size));
296extern voidp  calloc OF((uInt items, uInt size));
297extern void   free   OF((voidpf ptr));
298#endif
299
300voidpf zcalloc (opaque, items, size)
301    voidpf opaque;
302    unsigned items;
303    unsigned size;
304{
305    if (opaque) items += size - size; /* make compiler happy */
306    return sizeof(uInt) > 2 ? (voidpf)malloc(items * size) :
307                              (voidpf)calloc(items, size);
308}
309
310void  zcfree (opaque, ptr)
311    voidpf opaque;
312    voidpf ptr;
313{
314    free(ptr);
315    if (opaque) return; /* make compiler happy */
316}
317
318#endif /* MY_ZCALLOC */
319