cons.c revision 1.23 1 1.23 mycroft /* $NetBSD: cons.c,v 1.23 1994/12/14 19:09:13 mycroft Exp $ */
2 1.18 cgd
3 1.1 cgd /*
4 1.1 cgd * Copyright (c) 1988 University of Utah.
5 1.17 cgd * Copyright (c) 1990, 1993
6 1.17 cgd * The Regents of the University of California. All rights reserved.
7 1.1 cgd *
8 1.1 cgd * This code is derived from software contributed to Berkeley by
9 1.1 cgd * the Systems Programming Group of the University of Utah Computer
10 1.1 cgd * Science Department.
11 1.1 cgd *
12 1.1 cgd * Redistribution and use in source and binary forms, with or without
13 1.1 cgd * modification, are permitted provided that the following conditions
14 1.1 cgd * are met:
15 1.1 cgd * 1. Redistributions of source code must retain the above copyright
16 1.1 cgd * notice, this list of conditions and the following disclaimer.
17 1.1 cgd * 2. Redistributions in binary form must reproduce the above copyright
18 1.1 cgd * notice, this list of conditions and the following disclaimer in the
19 1.1 cgd * documentation and/or other materials provided with the distribution.
20 1.1 cgd * 3. All advertising materials mentioning features or use of this software
21 1.1 cgd * must display the following acknowledgement:
22 1.1 cgd * This product includes software developed by the University of
23 1.1 cgd * California, Berkeley and its contributors.
24 1.1 cgd * 4. Neither the name of the University nor the names of its contributors
25 1.1 cgd * may be used to endorse or promote products derived from this software
26 1.1 cgd * without specific prior written permission.
27 1.1 cgd *
28 1.1 cgd * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
29 1.1 cgd * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
30 1.1 cgd * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
31 1.1 cgd * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
32 1.1 cgd * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
33 1.1 cgd * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
34 1.1 cgd * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
35 1.1 cgd * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
36 1.1 cgd * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
37 1.1 cgd * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
38 1.1 cgd * SUCH DAMAGE.
39 1.1 cgd *
40 1.17 cgd * from: Utah $Hdr: cons.c 1.7 92/01/21$
41 1.17 cgd *
42 1.17 cgd * @(#)cons.c 8.2 (Berkeley) 1/12/94
43 1.1 cgd */
44 1.1 cgd
45 1.10 cgd #include <sys/param.h>
46 1.10 cgd #include <sys/proc.h>
47 1.10 cgd #include <sys/user.h>
48 1.10 cgd #include <sys/systm.h>
49 1.10 cgd #include <sys/buf.h>
50 1.10 cgd #include <sys/ioctl.h>
51 1.10 cgd #include <sys/tty.h>
52 1.10 cgd #include <sys/file.h>
53 1.10 cgd #include <sys/conf.h>
54 1.10 cgd #include <sys/vnode.h>
55 1.1 cgd
56 1.11 cgd #include <dev/cons.h>
57 1.1 cgd
58 1.10 cgd extern struct consdev constab[];
59 1.1 cgd
60 1.10 cgd struct tty *constty = NULL; /* virtual console output device */
61 1.1 cgd struct consdev *cn_tab; /* physical console device info */
62 1.13 cgd struct vnode *cn_devvp; /* vnode for underlying device. */
63 1.13 cgd
64 1.6 deraadt
65 1.7 andrew void
66 1.1 cgd cninit()
67 1.1 cgd {
68 1.1 cgd register struct consdev *cp;
69 1.1 cgd
70 1.1 cgd /*
71 1.1 cgd * Collect information about all possible consoles
72 1.1 cgd * and find the one with highest priority
73 1.1 cgd */
74 1.1 cgd for (cp = constab; cp->cn_probe; cp++) {
75 1.1 cgd (*cp->cn_probe)(cp);
76 1.1 cgd if (cp->cn_pri > CN_DEAD &&
77 1.1 cgd (cn_tab == NULL || cp->cn_pri > cn_tab->cn_pri))
78 1.1 cgd cn_tab = cp;
79 1.1 cgd }
80 1.1 cgd /*
81 1.1 cgd * No console, we can handle it
82 1.1 cgd */
83 1.1 cgd if ((cp = cn_tab) == NULL)
84 1.1 cgd return;
85 1.1 cgd /*
86 1.1 cgd * Turn on console
87 1.1 cgd */
88 1.1 cgd (*cp->cn_init)(cp);
89 1.1 cgd }
90 1.1 cgd
91 1.7 andrew int
92 1.1 cgd cnopen(dev, flag, mode, p)
93 1.1 cgd dev_t dev;
94 1.1 cgd int flag, mode;
95 1.1 cgd struct proc *p;
96 1.1 cgd {
97 1.21 mycroft
98 1.1 cgd if (cn_tab == NULL)
99 1.1 cgd return (0);
100 1.10 cgd
101 1.10 cgd /*
102 1.10 cgd * always open the 'real' console device, so we don't get nailed
103 1.10 cgd * later. This follows normal device semantics; they always get
104 1.10 cgd * open() calls.
105 1.10 cgd */
106 1.1 cgd dev = cn_tab->cn_dev;
107 1.13 cgd if (cn_devvp == NULLVP) {
108 1.15 cgd /* try to get a reference on its vnode, but fail silently */
109 1.15 cgd cdevvp(dev, &cn_devvp);
110 1.13 cgd }
111 1.23 mycroft return ((*cdevsw[major(dev)].d_open)(dev, flag, mode, p));
112 1.1 cgd }
113 1.1 cgd
114 1.7 andrew int
115 1.1 cgd cnclose(dev, flag, mode, p)
116 1.1 cgd dev_t dev;
117 1.1 cgd int flag, mode;
118 1.1 cgd struct proc *p;
119 1.1 cgd {
120 1.10 cgd struct vnode *vp;
121 1.10 cgd
122 1.1 cgd if (cn_tab == NULL)
123 1.1 cgd return (0);
124 1.10 cgd
125 1.10 cgd /*
126 1.10 cgd * If the real console isn't otherwise open, close it.
127 1.10 cgd * If it's otherwise open, don't close it, because that'll
128 1.10 cgd * screw up others who have it open.
129 1.10 cgd */
130 1.1 cgd dev = cn_tab->cn_dev;
131 1.13 cgd if (cn_devvp != NULLVP) {
132 1.13 cgd /* release our reference to real dev's vnode */
133 1.13 cgd vrele(cn_devvp);
134 1.13 cgd cn_devvp = NULLVP;
135 1.13 cgd }
136 1.16 mycroft if (vfinddev(dev, VCHR, &vp) && vcount(vp))
137 1.10 cgd return (0);
138 1.1 cgd return ((*cdevsw[major(dev)].d_close)(dev, flag, mode, p));
139 1.1 cgd }
140 1.1 cgd
141 1.7 andrew int
142 1.1 cgd cnread(dev, uio, flag)
143 1.1 cgd dev_t dev;
144 1.1 cgd struct uio *uio;
145 1.1 cgd {
146 1.21 mycroft
147 1.10 cgd /*
148 1.10 cgd * If we would redirect input, punt. This will keep strange
149 1.10 cgd * things from happening to people who are using the real
150 1.10 cgd * console. Nothing should be using /dev/console for
151 1.10 cgd * input (except a shell in single-user mode, but then,
152 1.10 cgd * one wouldn't TIOCCONS then).
153 1.10 cgd */
154 1.10 cgd if (constty != NULL && (cn_tab == NULL || cn_tab->cn_pri != CN_REMOTE))
155 1.10 cgd return 0;
156 1.10 cgd else if (cn_tab == NULL)
157 1.10 cgd return ENXIO;
158 1.10 cgd
159 1.1 cgd dev = cn_tab->cn_dev;
160 1.1 cgd return ((*cdevsw[major(dev)].d_read)(dev, uio, flag));
161 1.1 cgd }
162 1.1 cgd
163 1.7 andrew int
164 1.1 cgd cnwrite(dev, uio, flag)
165 1.1 cgd dev_t dev;
166 1.1 cgd struct uio *uio;
167 1.1 cgd {
168 1.21 mycroft
169 1.10 cgd /*
170 1.10 cgd * Redirect output, if that's appropriate.
171 1.10 cgd * If there's no real console, return ENXIO.
172 1.10 cgd */
173 1.10 cgd if (constty != NULL && (cn_tab == NULL || cn_tab->cn_pri != CN_REMOTE))
174 1.2 cgd dev = constty->t_dev;
175 1.10 cgd else if (cn_tab == NULL)
176 1.10 cgd return ENXIO;
177 1.2 cgd else
178 1.2 cgd dev = cn_tab->cn_dev;
179 1.1 cgd return ((*cdevsw[major(dev)].d_write)(dev, uio, flag));
180 1.1 cgd }
181 1.1 cgd
182 1.7 andrew int
183 1.1 cgd cnioctl(dev, cmd, data, flag, p)
184 1.1 cgd dev_t dev;
185 1.20 cgd u_long cmd;
186 1.1 cgd caddr_t data;
187 1.20 cgd int flag;
188 1.1 cgd struct proc *p;
189 1.1 cgd {
190 1.1 cgd int error;
191 1.1 cgd
192 1.1 cgd /*
193 1.1 cgd * Superuser can always use this to wrest control of console
194 1.1 cgd * output from the "virtual" console.
195 1.1 cgd */
196 1.10 cgd if (cmd == TIOCCONS && constty != NULL) {
197 1.1 cgd error = suser(p->p_ucred, (u_short *) NULL);
198 1.1 cgd if (error)
199 1.1 cgd return (error);
200 1.1 cgd constty = NULL;
201 1.1 cgd return (0);
202 1.1 cgd }
203 1.10 cgd
204 1.10 cgd /*
205 1.10 cgd * Redirect the ioctl, if that's appropriate.
206 1.10 cgd * Note that strange things can happen, if a program does
207 1.10 cgd * ioctls on /dev/console, then the console is redirected
208 1.10 cgd * out from under it.
209 1.10 cgd */
210 1.12 cgd if (constty != NULL && (cn_tab == NULL || cn_tab->cn_pri != CN_REMOTE))
211 1.10 cgd dev = constty->t_dev;
212 1.10 cgd else if (cn_tab == NULL)
213 1.10 cgd return ENXIO;
214 1.10 cgd else
215 1.10 cgd dev = cn_tab->cn_dev;
216 1.1 cgd return ((*cdevsw[major(dev)].d_ioctl)(dev, cmd, data, flag, p));
217 1.1 cgd }
218 1.1 cgd
219 1.1 cgd /*ARGSUSED*/
220 1.7 andrew int
221 1.1 cgd cnselect(dev, rw, p)
222 1.1 cgd dev_t dev;
223 1.1 cgd int rw;
224 1.1 cgd struct proc *p;
225 1.1 cgd {
226 1.21 mycroft
227 1.10 cgd /*
228 1.10 cgd * Redirect the ioctl, if that's appropriate.
229 1.10 cgd * I don't want to think of the possible side effects
230 1.10 cgd * of console redirection here.
231 1.10 cgd */
232 1.12 cgd if (constty != NULL && (cn_tab == NULL || cn_tab->cn_pri != CN_REMOTE))
233 1.10 cgd dev = constty->t_dev;
234 1.10 cgd else if (cn_tab == NULL)
235 1.10 cgd return ENXIO;
236 1.10 cgd else
237 1.10 cgd dev = cn_tab->cn_dev;
238 1.1 cgd return (ttselect(cn_tab->cn_dev, rw, p));
239 1.1 cgd }
240 1.1 cgd
241 1.7 andrew int
242 1.1 cgd cngetc()
243 1.1 cgd {
244 1.21 mycroft
245 1.1 cgd if (cn_tab == NULL)
246 1.1 cgd return (0);
247 1.1 cgd return ((*cn_tab->cn_getc)(cn_tab->cn_dev));
248 1.1 cgd }
249 1.1 cgd
250 1.7 andrew int
251 1.1 cgd cnputc(c)
252 1.1 cgd register int c;
253 1.1 cgd {
254 1.21 mycroft
255 1.1 cgd if (cn_tab == NULL)
256 1.1 cgd return;
257 1.1 cgd if (c) {
258 1.1 cgd (*cn_tab->cn_putc)(cn_tab->cn_dev, c);
259 1.1 cgd if (c == '\n')
260 1.1 cgd (*cn_tab->cn_putc)(cn_tab->cn_dev, '\r');
261 1.1 cgd }
262 1.19 mycroft }
263 1.19 mycroft
264 1.19 mycroft void
265 1.19 mycroft cnpollc(on)
266 1.19 mycroft int on;
267 1.19 mycroft {
268 1.19 mycroft static int refcount = 0;
269 1.19 mycroft
270 1.19 mycroft if (cn_tab == NULL)
271 1.19 mycroft return;
272 1.19 mycroft if (!on)
273 1.19 mycroft --refcount;
274 1.19 mycroft if (refcount == 0)
275 1.19 mycroft (*cn_tab->cn_pollc)(cn_tab->cn_dev, on);
276 1.19 mycroft if (on)
277 1.19 mycroft ++refcount;
278 1.21 mycroft }
279 1.21 mycroft
280 1.21 mycroft void
281 1.21 mycroft nullcnpollc(on)
282 1.21 mycroft int on;
283 1.21 mycroft {
284 1.21 mycroft
285 1.2 cgd }
286