1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
|
/* $OpenBSD: nullopen.c,v 1.2 2004/01/22 18:49:35 millert Exp $ */
/*
* Copyright (c) 2003 Can Erkin Acar
* Copyright (c) 1997 Michael Shalayeff
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*/
const char null_rcsid[] =
"$OpenBSD: nullopen.c,v 1.2 2004/01/22 18:49:35 millert Exp $";
#include <sys/types.h>
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <unistd.h>
#include "compress.h"
typedef struct {
off_t total_in;
off_t total_out;
int fd;
int gotmagic;
char mode;
} null_stream;
char null_magic[2];
void *
null_open(int fd, const char *mode, char *name, int bits,
u_int32_t mtime, int gotmagic)
{
null_stream *s;
if (fd < 0 || !mode)
return NULL;
if ((mode[0] != 'r' && mode[0] != 'w') || mode[1] != '\0') {
errno = EINVAL;
return NULL;
}
if ((s = (null_stream *) calloc(1, sizeof(null_stream))) == NULL)
return NULL;
s->fd = fd;
s->gotmagic = gotmagic;
s->total_in = s->total_out = 0;
s->mode = mode[0];
return s;
}
int
null_close(void *cookie, struct z_info *info)
{
null_stream *s = (null_stream*) cookie;
int err = 0;
if (s == NULL)
return -1;
if (info != NULL) {
info->mtime = 0;
info->crc = (u_int32_t)-1;
info->hlen = 0;
info->total_in = (off_t) s->total_in;
info->total_out = (off_t) s->total_out;
}
err = close(s->fd);
free(s);
return err;
}
int
null_flush(void *cookie, int flush)
{
null_stream *s = (null_stream*)cookie;
if (s == NULL || s->mode != 'w') {
errno = EBADF;
return (-1);
}
return 0;
}
int
null_read(void *cookie, char *buf, int len)
{
null_stream *s = (null_stream*)cookie;
if (s == NULL) {
errno = EBADF;
return (-1);
}
if (s->gotmagic) {
if (len < 2) {
errno = EBADF;
return (-1);
}
buf[0] = null_magic[0];
buf[1] = null_magic[1];
s->gotmagic = 0;
return (2);
}
return read(s->fd, buf, len);
}
int
null_write(void *cookie, const char *buf, int len)
{
null_stream *s = (null_stream*)cookie;
if (s == NULL) {
errno = EBADF;
return (-1);
}
return write(s->fd, buf, len);
}
|
