kern_cons.c revision 8023
1/*
2 * Copyright (c) 1988 University of Utah.
3 * Copyright (c) 1991 The Regents of the University of California.
4 * All rights reserved.
5 *
6 * This code is derived from software contributed to Berkeley by
7 * the Systems Programming Group of the University of Utah Computer
8 * Science Department.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 * 3. All advertising materials mentioning features or use of this software
19 *    must display the following acknowledgement:
20 *	This product includes software developed by the University of
21 *	California, Berkeley and its contributors.
22 * 4. Neither the name of the University nor the names of its contributors
23 *    may be used to endorse or promote products derived from this software
24 *    without specific prior written permission.
25 *
26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 * SUCH DAMAGE.
37 *
38 *	from: @(#)cons.c	7.2 (Berkeley) 5/9/91
39 *	$Id: cons.c,v 1.25 1995/04/08 21:31:51 joerg Exp $
40 */
41
42#include <sys/param.h>
43#include <sys/systm.h>
44#include <sys/conf.h>
45#include <sys/proc.h>
46#include <sys/tty.h>
47
48#include <machine/cons.h>
49#include <machine/stdarg.h>
50
51/* XXX this should be config(8)ed. */
52static struct consdev constab[] = {
53#if NSC > 0 || NVT > 0
54	{ pccnprobe,	pccninit,	pccngetc,	pccncheckc,	pccnputc },
55#endif
56#if NSIO > 0
57	{ siocnprobe,	siocninit,	siocngetc,	siocncheckc,	siocnputc },
58#endif
59	{ 0 },
60};
61
62struct	tty *constty = 0;	/* virtual console output device */
63struct	tty *cn_tty;		/* XXX: console tty struct for tprintf */
64int	cons_unavail = 0;	/* XXX:
65				 * physical console not available for
66				 * input (i.e., it is in graphics mode)
67				 */
68
69static u_char cn_is_open;	/* nonzero if logical console is open */
70static u_char cn_phys_is_open;	/* nonzero if physical console is open */
71static d_close_t *cn_phys_close;	/* physical device close function */
72static d_open_t *cn_phys_open;	/* physical device open function */
73static struct consdev *cn_tab;	/* physical console device info */
74static struct tty *cn_tp;	/* physical console tty struct */
75
76void
77cninit()
78{
79	register struct consdev *cp;
80	struct cdevsw *cdp;
81
82	/*
83	 * Collect information about all possible consoles
84	 * and find the one with highest priority
85	 */
86	for (cp = constab; cp->cn_probe; cp++) {
87		(*cp->cn_probe)(cp);
88		if (cp->cn_pri > CN_DEAD &&
89		    (cn_tab == NULL || cp->cn_pri > cn_tab->cn_pri))
90			cn_tab = cp;
91	}
92	/*
93	 * No console, give up.
94	 */
95	if ((cp = cn_tab) == NULL)
96		return;
97	/*
98	 * Hook the open and close functions.
99	 */
100	cdp = &cdevsw[major(cn_tab->cn_dev)];
101	cn_phys_close = cdp->d_close;
102	cdp->d_close = cnclose;
103	cn_phys_open = cdp->d_open;
104	cdp->d_open = cnopen;
105	cn_tp = (*cdp->d_devtotty)(cn_tab->cn_dev);
106	/*
107	 * Turn on console
108	 */
109	cn_tty = cp->cn_tp;
110	(*cp->cn_init)(cp);
111}
112
113int
114cnopen(dev, flag, mode, p)
115	dev_t dev;
116	int flag, mode;
117	struct proc *p;
118{
119	dev_t cndev, physdev;
120	int retval;
121
122	if (cn_tab == NULL)
123		return (0);
124	cndev = cn_tab->cn_dev;
125	physdev = (major(dev) == major(cndev) ? dev : cndev);
126	retval = (*cn_phys_open)(physdev, flag, mode, p);
127	if (retval == 0) {
128		if (dev == cndev)
129			cn_phys_is_open = 1;
130		else if (physdev == cndev)
131			cn_is_open = 1;
132	}
133	return (retval);
134}
135
136int
137cnclose(dev, flag, mode, p)
138	dev_t dev;
139	int flag, mode;
140	struct proc *p;
141{
142	dev_t cndev;
143
144	if (cn_tab == NULL)
145		return (0);
146	cndev = cn_tab->cn_dev;
147	if (dev == cndev) {
148		/* the physical device is about to be closed */
149		cn_phys_is_open = 0;
150		if (cn_is_open) {
151			if (cn_tp) {
152				/* perform a ttyhalfclose() */
153				/* reset session and proc group */
154				cn_tp->t_pgrp = NULL;
155				cn_tp->t_session = NULL;
156			}
157			return (0);
158		}
159	} else if (major(dev) != major(cndev)) {
160		/* the logical console is about to be closed */
161		cn_is_open = 0;
162		if (cn_phys_is_open)
163			return (0);
164		dev = cndev;
165	}
166	return ((*cn_phys_close)(dev, flag, mode, p));
167}
168
169int
170cnread(dev, uio, flag)
171	dev_t dev;
172	struct uio *uio;
173	int flag;
174{
175	if (cn_tab == NULL)
176		return (0);
177	dev = cn_tab->cn_dev;
178	return ((*cdevsw[major(dev)].d_read)(dev, uio, flag));
179}
180
181int
182cnwrite(dev, uio, flag)
183	dev_t dev;
184	struct uio *uio;
185	int flag;
186{
187	if (cn_tab == NULL)
188		return (0);
189	if (constty)
190		dev = constty->t_dev;
191	else
192		dev = cn_tab->cn_dev;
193	return ((*cdevsw[major(dev)].d_write)(dev, uio, flag));
194}
195
196int
197cnioctl(dev, cmd, data, flag, p)
198	dev_t dev;
199	int cmd;
200	caddr_t data;
201	int flag;
202	struct proc *p;
203{
204	int error;
205
206	if (cn_tab == NULL)
207		return (0);
208	/*
209	 * Superuser can always use this to wrest control of console
210	 * output from the "virtual" console.
211	 */
212	if (cmd == TIOCCONS && constty) {
213		error = suser(p->p_ucred, (u_short *) NULL);
214		if (error)
215			return (error);
216		constty = NULL;
217		return (0);
218	}
219	dev = cn_tab->cn_dev;
220	return ((*cdevsw[major(dev)].d_ioctl)(dev, cmd, data, flag, p));
221}
222
223/*ARGSUSED*/
224int
225cnselect(dev, rw, p)
226	dev_t dev;
227	int rw;
228	struct proc *p;
229{
230	if (cn_tab == NULL)
231		return (1);
232
233	dev = cn_tab->cn_dev;
234
235	return ((*cdevsw[major(dev)].d_select)(dev, rw, p));
236}
237
238int
239cngetc()
240{
241	int c;
242	if (cn_tab == NULL)
243		return (0);
244	c = (*cn_tab->cn_getc)(cn_tab->cn_dev);
245	if (c == '\r') c = '\n'; /* console input is always ICRNL */
246	return (c);
247}
248
249int
250cncheckc()
251{
252	if (cn_tab == NULL)
253		return (0);
254	return ((*cn_tab->cn_checkc)(cn_tab->cn_dev));
255}
256
257void
258cnputc(c)
259	register int c;
260{
261	if (cn_tab == NULL)
262		return;
263	if (c) {
264		(*cn_tab->cn_putc)(cn_tab->cn_dev, c);
265		if (c == '\n')
266			(*cn_tab->cn_putc)(cn_tab->cn_dev, '\r');
267	}
268}
269
270int
271pg(const char *p, ...) {
272  va_list args;
273  va_start(args, p);
274  printf("%r\n>", p, args);
275  return(cngetc());
276}
277
278
279