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
13z_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
27const char * ZEXPORT zlibVersion(void) {
28    return ZLIB_VERSION;
29}
30
31uLong 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
120int ZLIB_INTERNAL z_verbose = verbose;
121
122void 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 */
131const 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
145void 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
152int 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
161void 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
187local int next_ptr = 0;
188
189typedef struct ptr_table_s {
190    voidpf org_ptr;
191    voidpf new_ptr;
192} ptr_table;
193
194local 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
202voidpf 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
227void 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
263voidpf ZLIB_INTERNAL zcalloc(voidpf opaque, uInt items, uInt size) {
264    (void)opaque;
265    return _halloc((long)items, size);
266}
267
268void 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
281extern voidp malloc(uInt size);
282extern voidp calloc(uInt items, uInt size);
283extern void free(voidpf ptr);
284#endif
285
286voidpf 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
292void 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