kern_cons.c revision 9326 
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 1.29 1995/06/14 04:52:39 bde 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. */
52#include "sc.h"
53#include "vt.h"
54#include "sio.h"
55static struct consdev constab[] = {
56#if NSC > 0 || NVT > 0
57	{ pccnprobe,	pccninit,	pccngetc,	pccncheckc,	pccnputc },
58#endif
59#if NSIO > 0
60	{ siocnprobe,	siocninit,	siocngetc,	siocncheckc,	siocnputc },
61#endif
62	{ 0 },
63};
64
65struct	tty *constty = 0;	/* virtual console output device */
66struct	tty *cn_tty;		/* XXX: console tty struct for tprintf */
67int	cons_unavail = 0;	/* XXX:
68				 * physical console not available for
69				 * input (i.e., it is in graphics mode)
70				 */
71
72static u_char cn_is_open;	/* nonzero if logical console is open */
73static u_char cn_phys_is_open;	/* nonzero if physical console is open */
74static d_close_t *cn_phys_close;	/* physical device close function */
75static d_open_t *cn_phys_open;	/* physical device open function */
76static struct consdev *cn_tab;	/* physical console device info */
77static struct tty *cn_tp;	/* physical console tty struct */
78
79void
80cninit()
81{
82	register struct consdev *cp;
83	struct cdevsw *cdp;
84
85	/*
86	 * Collect information about all possible consoles
87	 * and find the one with highest priority
88	 */
89	for (cp = constab; cp->cn_probe; cp++) {
90		(*cp->cn_probe)(cp);
91		if (cp->cn_pri > CN_DEAD &&
92		    (cn_tab == NULL || cp->cn_pri > cn_tab->cn_pri))
93			cn_tab = cp;
94	}
95	/*
96	 * No console, give up.
97	 */
98	if ((cp = cn_tab) == NULL)
99		return;
100	/*
101	 * Hook the open and close functions.
102	 */
103	cdp = &cdevsw[major(cn_tab->cn_dev)];
104	cn_phys_close = cdp->d_close;
105	cdp->d_close = cnclose;
106	cn_phys_open = cdp->d_open;
107	cdp->d_open = cnopen;
108	cn_tp = (*cdp->d_devtotty)(cn_tab->cn_dev);
109	/*
110	 * XXX there are too many tty pointers.  cn_tty is only used for
111	 * sysctl(CPU_CONSDEV) (not for tprintf like the above comment
112	 * says).  cn_tp in struct consdev hasn't been initialized
113	 * (except statically to NULL) or used (except to initialize
114	 * cn_tty to the wrong value) for a year or two.
115	 */
116	cn_tty = cn_tp;
117	/*
118	 * Turn on console
119	 */
120	(*cp->cn_init)(cp);
121}
122
123int
124cnopen(dev, flag, mode, p)
125	dev_t dev;
126	int flag, mode;
127	struct proc *p;
128{
129	dev_t cndev, physdev;
130	int retval;
131
132	if (cn_tab == NULL)
133		return (0);
134	cndev = cn_tab->cn_dev;
135	physdev = (major(dev) == major(cndev) ? dev : cndev);
136	retval = (*cn_phys_open)(physdev, flag, mode, p);
137	if (retval == 0) {
138		if (dev == cndev)
139			cn_phys_is_open = 1;
140		else if (physdev == cndev)
141			cn_is_open = 1;
142	}
143	return (retval);
144}
145
146int
147cnclose(dev, flag, mode, p)
148	dev_t dev;
149	int flag, mode;
150	struct proc *p;
151{
152	dev_t cndev;
153
154	if (cn_tab == NULL)
155		return (0);
156	cndev = cn_tab->cn_dev;
157	if (dev == cndev) {
158		/* the physical device is about to be closed */
159		cn_phys_is_open = 0;
160		if (cn_is_open) {
161			if (cn_tp) {
162				/* perform a ttyhalfclose() */
163				/* reset session and proc group */
164				cn_tp->t_pgrp = NULL;
165				cn_tp->t_session = NULL;
166			}
167			return (0);
168		}
169	} else if (major(dev) != major(cndev)) {
170		/* the logical console is about to be closed */
171		cn_is_open = 0;
172		if (cn_phys_is_open)
173			return (0);
174		dev = cndev;
175	}
176	return ((*cn_phys_close)(dev, flag, mode, p));
177}
178
179int
180cnread(dev, uio, flag)
181	dev_t dev;
182	struct uio *uio;
183	int flag;
184{
185	if (cn_tab == NULL)
186		return (0);
187	dev = cn_tab->cn_dev;
188	return ((*cdevsw[major(dev)].d_read)(dev, uio, flag));
189}
190
191int
192cnwrite(dev, uio, flag)
193	dev_t dev;
194	struct uio *uio;
195	int flag;
196{
197	if (cn_tab == NULL)
198		return (0);
199	if (constty)
200		dev = constty->t_dev;
201	else
202		dev = cn_tab->cn_dev;
203	return ((*cdevsw[major(dev)].d_write)(dev, uio, flag));
204}
205
206int
207cnioctl(dev, cmd, data, flag, p)
208	dev_t dev;
209	int cmd;
210	caddr_t data;
211	int flag;
212	struct proc *p;
213{
214	int error;
215
216	if (cn_tab == NULL)
217		return (0);
218	/*
219	 * Superuser can always use this to wrest control of console
220	 * output from the "virtual" console.
221	 */
222	if (cmd == TIOCCONS && constty) {
223		error = suser(p->p_ucred, (u_short *) NULL);
224		if (error)
225			return (error);
226		constty = NULL;
227		return (0);
228	}
229	dev = cn_tab->cn_dev;
230	return ((*cdevsw[major(dev)].d_ioctl)(dev, cmd, data, flag, p));
231}
232
233/*ARGSUSED*/
234int
235cnselect(dev, rw, p)
236	dev_t dev;
237	int rw;
238	struct proc *p;
239{
240	if (cn_tab == NULL)
241		return (1);
242
243	dev = cn_tab->cn_dev;
244
245	return ((*cdevsw[major(dev)].d_select)(dev, rw, p));
246}
247
248int
249cngetc()
250{
251	int c;
252	if (cn_tab == NULL)
253		return (0);
254	c = (*cn_tab->cn_getc)(cn_tab->cn_dev);
255	if (c == '\r') c = '\n'; /* console input is always ICRNL */
256	return (c);
257}
258
259int
260cncheckc()
261{
262	if (cn_tab == NULL)
263		return (0);
264	return ((*cn_tab->cn_checkc)(cn_tab->cn_dev));
265}
266
267void
268cnputc(c)
269	register int c;
270{
271	if (cn_tab == NULL)
272		return;
273	if (c) {
274		if (c == '\n')
275			(*cn_tab->cn_putc)(cn_tab->cn_dev, '\r');
276		(*cn_tab->cn_putc)(cn_tab->cn_dev, c);
277	}
278}
279
280int
281pg(const char *p, ...) {
282  va_list args;
283  va_start(args, p);
284  printf("%r\n>", p, args);
285  return(cngetc());
286}
287
288
289