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
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
|
/* $OpenBSD: cons.c,v 1.27 2017/12/30 20:46:59 guenther Exp $ */
/* $NetBSD: cons.c,v 1.30 1996/04/08 19:57:30 jonathan Exp $ */
/*
* Copyright (c) 1988 University of Utah.
* Copyright (c) 1990, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* the Systems Programming Group of the University of Utah Computer
* Science Department.
*
* 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.
* 3. 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.
*
* from: Utah $Hdr: cons.c 1.7 92/01/21$
*
* @(#)cons.c 8.2 (Berkeley) 1/12/94
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/ioctl.h>
#include <sys/tty.h>
#include <sys/conf.h>
#include <sys/vnode.h>
#include <sys/poll.h>
#include <dev/cons.h>
struct tty *constty = NULL; /* virtual console output device */
struct vnode *cn_devvp = NULLVP; /* vnode for underlying device. */
int
cnopen(dev_t dev, int flag, int mode, struct proc *p)
{
dev_t cndev;
if (cn_tab == NULL)
return (0);
/*
* always open the 'real' console device, so we don't get nailed
* later. This follows normal device semantics; they always get
* open() calls.
*/
cndev = cn_tab->cn_dev;
if (cndev == NODEV)
return (ENXIO);
#ifdef DIAGNOSTIC
if (cndev == dev)
panic("cnopen: recursive");
#endif
if (cn_devvp == NULLVP) {
/* try to get a reference on its vnode, but fail silently */
cdevvp(cndev, &cn_devvp);
}
return ((*cdevsw[major(cndev)].d_open)(cndev, flag, mode, p));
}
int
cnclose(dev_t dev, int flag, int mode, struct proc *p)
{
struct vnode *vp;
if (cn_tab == NULL)
return (0);
/*
* If the real console isn't otherwise open, close it.
* If it's otherwise open, don't close it, because that'll
* screw up others who have it open.
*/
dev = cn_tab->cn_dev;
if (cn_devvp != NULLVP) {
/* release our reference to real dev's vnode */
vrele(cn_devvp);
cn_devvp = NULLVP;
}
if (vfinddev(dev, VCHR, &vp) && vcount(vp))
return (0);
return ((*cdevsw[major(dev)].d_close)(dev, flag, mode, p));
}
int
cnread(dev_t dev, struct uio *uio, int flag)
{
/*
* If we would redirect input, punt. This will keep strange
* things from happening to people who are using the real
* console. Nothing should be using /dev/console for
* input (except a shell in single-user mode, but then,
* one wouldn't TIOCCONS then).
*/
if (constty != NULL)
return 0;
else if (cn_tab == NULL)
return ENXIO;
dev = cn_tab->cn_dev;
return ((*cdevsw[major(dev)].d_read)(dev, uio, flag));
}
int
cnwrite(dev_t dev, struct uio *uio, int flag)
{
/*
* Redirect output, if that's appropriate.
* If there's no real console, return ENXIO.
*/
if (constty != NULL)
dev = constty->t_dev;
else if (cn_tab == NULL)
return ENXIO;
else
dev = cn_tab->cn_dev;
return ((*cdevsw[major(dev)].d_write)(dev, uio, flag));
}
int
cnstop(struct tty *tp, int flag)
{
return (0);
}
int
cnioctl(dev_t dev, u_long cmd, caddr_t data, int flag,
struct proc *p)
{
int error;
/*
* Superuser can always use this to wrest control of console
* output from the "virtual" console.
*/
if (cmd == TIOCCONS && constty != NULL) {
error = suser(p, SUSER_NOACCT);
if (error)
return (error);
constty = NULL;
return (0);
}
/*
* Redirect the ioctl, if that's appropriate.
* Note that strange things can happen, if a program does
* ioctls on /dev/console, then the console is redirected
* out from under it.
*/
if (constty != NULL)
dev = constty->t_dev;
else if (cn_tab == NULL)
return ENXIO;
else
dev = cn_tab->cn_dev;
return ((*cdevsw[major(dev)].d_ioctl)(dev, cmd, data, flag, p));
}
/*ARGSUSED*/
int
cnpoll(dev_t dev, int rw, struct proc *p)
{
/*
* Redirect the poll, if that's appropriate.
* I don't want to think of the possible side effects
* of console redirection here.
*/
if (constty != NULL)
dev = constty->t_dev;
else if (cn_tab == NULL)
return POLLERR;
else
dev = cn_tab->cn_dev;
return (ttpoll(dev, rw, p));
}
int
cnkqfilter(dev_t dev, struct knote *kn)
{
/*
* Redirect output, if that's appropriate.
* If there's no real console, return 1.
*/
if (constty != NULL)
dev = constty->t_dev;
else if (cn_tab == NULL)
return (ENXIO);
else
dev = cn_tab->cn_dev;
if (cdevsw[major(dev)].d_kqfilter)
return ((*cdevsw[major(dev)].d_kqfilter)(dev, kn));
return (ENXIO);
}
int
cngetc(void)
{
if (cn_tab == NULL)
return (0);
return ((*cn_tab->cn_getc)(cn_tab->cn_dev));
}
void
cnputc(int c)
{
if (cn_tab == NULL)
return;
if (c) {
(*cn_tab->cn_putc)(cn_tab->cn_dev, c);
if (c == '\n')
(*cn_tab->cn_putc)(cn_tab->cn_dev, '\r');
}
}
void
cnpollc(int on)
{
static int refcount = 0;
if (cn_tab == NULL)
return;
if (!on)
--refcount;
if (refcount == 0)
(*cn_tab->cn_pollc)(cn_tab->cn_dev, on);
if (on)
++refcount;
}
void
nullcnpollc(dev_t dev, int on)
{
}
void
cnbell(u_int pitch, u_int period, u_int volume)
{
if (cn_tab == NULL || cn_tab->cn_bell == NULL)
return;
(*cn_tab->cn_bell)(cn_tab->cn_dev, pitch, period, volume);
}
|
