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1/* zutil.c -- target dependent utility functions for the compression library
2 * Copyright (C) 1995 Jean-loup Gailly.
3 * For conditions of distribution and use, see copyright notice in zlib.h
4 */
5
6/* $Id: zutil.c,v 1.3 1995/04/10 09:52:26 jloup Exp $ */
7
8#include <stdio.h>
9
10#include "zutil.h"
11
12char *zlib_version = ZLIB_VERSION;
13
14char *z_errmsg[] = {
15"stream end", /* Z_STREAM_END 1 */
16"", /* Z_OK 0 */
17"file error", /* Z_ERRNO (-1) */
18"stream error", /* Z_STREAM_ERROR (-2) */
19"data error", /* Z_DATA_ERROR (-3) */
20"insufficient memory", /* Z_MEM_ERROR (-4) */
21"buffer error", /* Z_BUF_ERROR (-5) */
22""};
23
24
25void z_error (m)
26 char *m;
27{
28 fprintf(stderr, "%s\n", m);
29 exit(1);
30}
31
32#ifndef HAVE_MEMCPY
33
34void zmemcpy(dest, source, len)
35 Byte* dest;
36 Byte* source;
37 uInt len;
38{
39 if (len == 0) return;
40 do {
41 *dest++ = *source++; /* ??? to be unrolled */
42 } while (--len != 0);
43}
44
45void zmemzero(dest, len)
46 Byte* dest;
47 uInt len;
48{
49 if (len == 0) return;
50 do {
51 *dest++ = 0; /* ??? to be unrolled */
52 } while (--len != 0);
53}
54#endif
55
56#if defined(MSDOS) && !defined(USE_CALLOC)
57# ifdef __TURBOC__
58
59/* Turbo C malloc() does not allow dynamic allocation of 64K bytes
60 * and farmalloc(64K) returns a pointer with an offset of 8, so we
61 * must fix the pointer. Warning: the pointer must be put back to its
62 * original form in order to free it, use zcfree().
63 */
64
65#define MAX_PTR 10
66/* 10*64K = 640K */
67
68local int next_ptr = 0;
69
70typedef struct ptr_table_s {
71 voidp org_ptr;
72 voidp new_ptr;
73} ptr_table;
74
75local ptr_table table[MAX_PTR];
76/* This table is used to remember the original form of pointers
77 * to large buffers (64K). Such pointers are normalized with a zero offset.
78 * Since MSDOS is not a preemptive multitasking OS, this table is not
79 * protected from concurrent access. This hack doesn't work anyway on
80 * a protected system like OS/2. Use Microsoft C instead.
81 */
82
83voidp zcalloc (voidp opaque, unsigned items, unsigned size)
84{
85 voidp buf;
86 ulg bsize = (ulg)items*size;
87
88 if (bsize < 65536L) {
89 buf = farmalloc(bsize);
90 if (*(ush*)&buf != 0) return buf;
91 } else {
92 buf = farmalloc(bsize + 16L);
93 }
94 if (buf == NULL || next_ptr >= MAX_PTR) return NULL;
95 table[next_ptr].org_ptr = buf;
96
97 /* Normalize the pointer to seg:0 */
98 *((ush*)&buf+1) += ((ush)((uch*)buf-0) + 15) >> 4;
99 *(ush*)&buf = 0;
100 table[next_ptr++].new_ptr = buf;
101 return buf;
102}
103
104void zcfree (voidp opaque, voidp ptr)
105{
106 int n;
107 if (*(ush*)&ptr != 0) { /* object < 64K */
108 farfree(ptr);
109 return;
110 }
111 /* Find the original pointer */
112 for (n = 0; n < next_ptr; n++) {
113 if (ptr != table[n].new_ptr) continue;
114
115 farfree(table[n].org_ptr);
116 while (++n < next_ptr) {
117 table[n-1] = table[n];
118 }
119 next_ptr--;
120 return;
121 }
122 z_error("zcfree: ptr not found");
123}
124
125# else /* MSC */
126
127#if (!defined(_MSC_VER) || (_MSC_VER < 600))
128# define _halloc halloc
129# define _hfree hfree
130#endif
131
132voidp zcalloc (voidp opaque, unsigned items, unsigned size)
133{
134 return _halloc((long)items, size);
135}
136
137void zcfree (voidp opaque, voidp ptr)
138{
139 return _hfree(ptr);
140}
141
142# endif /* __TURBOC__ ? */
143
144#else /* !MSDOS */
145
146extern voidp calloc __P((uInt items, uInt size));
147extern void free __P((voidp ptr));
148
149voidp zcalloc (opaque, items, size)
150 voidp opaque;
151 unsigned items;
152 unsigned size;
153{
154 return calloc(items, size);
155}
156
157void zcfree (opaque, ptr)
158 voidp opaque;
159 voidp ptr;
160{
161 free(ptr);
162}
163
164#endif /* MSDOS */