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
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
|
/*-
* Copyright (c) 2004 Poul-Henning Kamp. All rights reserved.
* Copyright (c) 1982, 1986, 1991, 1993
* The Regents of the University of California. All rights reserved.
* (c) UNIX System Laboratories, Inc.
* All or some portions of this file are derived from material licensed
* to the University of California by American Telephone and Telegraph
* Co. or Unix System Laboratories, Inc. and are reproduced herein with
* the permission of UNIX System Laboratories, Inc.
*
* 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.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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.
*
* @(#)tty_conf.c 8.4 (Berkeley) 1/21/94
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_compat.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/tty.h>
#include <sys/conf.h>
#ifndef MAXLDISC
#define MAXLDISC 9
#endif
static l_open_t l_noopen;
static l_close_t l_noclose;
static l_rint_t l_norint;
static l_start_t l_nostart;
/*
* XXX it probably doesn't matter what the entries other than the l_open
* entry are here. The l_nullioctl and ttymodem entries still look fishy.
* Reconsider the removal of nullmodem anyway. It was too much like
* ttymodem, but a completely null version might be useful.
*/
static struct linesw nodisc = {
.l_open = l_noopen,
.l_close = l_noclose,
.l_read = l_noread,
.l_write = l_nowrite,
.l_ioctl = l_nullioctl,
.l_rint = l_norint,
.l_start = l_nostart,
.l_modem = ttymodem
};
static struct linesw termios_disc = {
.l_open = ttyopen,
.l_close = ttylclose,
.l_read = ttread,
.l_write = ttwrite,
.l_ioctl = l_nullioctl,
.l_rint = ttyinput,
.l_start = ttstart,
.l_modem = ttymodem
};
#ifdef COMPAT_43
# define ntty_disc termios_disc
#else
# define ntty_disc nodisc
#endif
struct linesw *linesw[MAXLDISC] = {
&termios_disc, /* 0 - termios */
&nodisc, /* 1 - defunct */
&ntty_disc, /* 2 - NTTYDISC */
&nodisc, /* 3 - loadable */
&nodisc, /* 4 - SLIPDISC */
&nodisc, /* 5 - PPPDISC */
&nodisc, /* 6 - NETGRAPHDISC */
&nodisc, /* 7 - loadable */
&nodisc, /* 8 - loadable */
};
int nlinesw = sizeof (linesw) / sizeof (linesw[0]);
#define LOADABLE_LDISC 7
/*
* ldisc_register: Register a line discipline.
*
* discipline: Index for discipline to load, or LDISC_LOAD for us to choose.
* linesw_p: Pointer to linesw_p.
*
* Returns: Index used or -1 on failure.
*/
int
ldisc_register(int discipline, struct linesw *linesw_p)
{
int slot = -1;
if (discipline == LDISC_LOAD) {
int i;
for (i = LOADABLE_LDISC; i < MAXLDISC; i++)
if (linesw[i] == &nodisc) {
slot = i;
break;
}
} else if (discipline >= 0 && discipline < MAXLDISC) {
slot = discipline;
}
if (slot != -1 && linesw_p)
linesw[slot] = linesw_p;
return slot;
}
/*
* ldisc_deregister: Deregister a line discipline obtained with
* ldisc_register.
*
* discipline: Index for discipline to unload.
*/
void
ldisc_deregister(int discipline)
{
if (discipline < MAXLDISC)
linesw[discipline] = &nodisc;
}
/*
* "no" and "null" versions of line discipline functions
*/
static int
l_noopen(struct cdev *dev, struct tty *tp)
{
return (ENODEV);
}
static int
l_noclose(struct tty *tp, int flag)
{
return (ENODEV);
}
int
l_noread(struct tty *tp, struct uio *uio, int flag)
{
return (ENODEV);
}
int
l_nowrite(struct tty *tp, struct uio *uio, int flag)
{
return (ENODEV);
}
static int
l_norint(int c, struct tty *tp)
{
return (ENODEV);
}
static int
l_nostart(struct tty *tp)
{
return (ENODEV);
}
int
l_nullioctl(struct tty *tp, u_long cmd, char *data, int flags, struct thread *td)
{
return (ENOIOCTL);
}
|
