Initial import from FreeBSD RELENG_4:
[dragonfly.git] / sys / kern / tty_cons.c
CommitLineData
984263bc
MD
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 * $FreeBSD: src/sys/kern/tty_cons.c,v 1.81.2.4 2001/12/17 18:44:41 guido Exp $
40 */
41
42#include "opt_ddb.h"
43
44#include <sys/param.h>
45#include <sys/systm.h>
46#include <sys/conf.h>
47#include <sys/cons.h>
48#include <sys/kernel.h>
49#include <sys/proc.h>
50#include <sys/reboot.h>
51#include <sys/sysctl.h>
52#include <sys/tty.h>
53#include <sys/uio.h>
54
55#include <ddb/ddb.h>
56
57#include <machine/cpu.h>
58
59static d_open_t cnopen;
60static d_close_t cnclose;
61static d_read_t cnread;
62static d_write_t cnwrite;
63static d_ioctl_t cnioctl;
64static d_poll_t cnpoll;
65static d_kqfilter_t cnkqfilter;
66
67#define CDEV_MAJOR 0
68static struct cdevsw cn_cdevsw = {
69 /* open */ cnopen,
70 /* close */ cnclose,
71 /* read */ cnread,
72 /* write */ cnwrite,
73 /* ioctl */ cnioctl,
74 /* poll */ cnpoll,
75 /* mmap */ nommap,
76 /* strategy */ nostrategy,
77 /* name */ "console",
78 /* maj */ CDEV_MAJOR,
79 /* dump */ nodump,
80 /* psize */ nopsize,
81 /* flags */ D_TTY | D_KQFILTER,
82 /* bmaj */ -1,
83 /* kqfilter */ cnkqfilter,
84};
85
86static dev_t cn_dev_t; /* seems to be never really used */
87static udev_t cn_udev_t;
88SYSCTL_OPAQUE(_machdep, CPU_CONSDEV, consdev, CTLFLAG_RD,
89 &cn_udev_t, sizeof cn_udev_t, "T,dev_t", "");
90
91static int cn_mute;
92
93int cons_unavail = 0; /* XXX:
94 * physical console not available for
95 * input (i.e., it is in graphics mode)
96 */
97
98static u_char cn_is_open; /* nonzero if logical console is open */
99static int openmode, openflag; /* how /dev/console was openned */
100static dev_t cn_devfsdev; /* represents the device private info */
101static u_char cn_phys_is_open; /* nonzero if physical device is open */
102static d_close_t *cn_phys_close; /* physical device close function */
103static d_open_t *cn_phys_open; /* physical device open function */
104 struct consdev *cn_tab; /* physical console device info */
105static u_char console_pausing; /* pause after each line during probe */
106static char *console_pausestr=
107"<pause; press any key to proceed to next line or '.' to end pause mode>";
108
109CONS_DRIVER(cons, NULL, NULL, NULL, NULL, NULL, NULL, NULL);
110
111void
112cninit()
113{
114 struct consdev *best_cp, *cp, **list;
115
116 /*
117 * Find the first console with the highest priority.
118 */
119 best_cp = NULL;
120 list = (struct consdev **)cons_set.ls_items;
121 while ((cp = *list++) != NULL) {
122 if (cp->cn_probe == NULL)
123 continue;
124 (*cp->cn_probe)(cp);
125 if (cp->cn_pri > CN_DEAD &&
126 (best_cp == NULL || cp->cn_pri > best_cp->cn_pri))
127 best_cp = cp;
128 }
129
130 /*
131 * Check if we should mute the console (for security reasons perhaps)
132 * It can be changes dynamically using sysctl kern.consmute
133 * once we are up and going.
134 *
135 */
136 cn_mute = ((boothowto & (RB_MUTE
137 |RB_SINGLE
138 |RB_VERBOSE
139 |RB_ASKNAME
140 |RB_CONFIG)) == RB_MUTE);
141
142 /*
143 * If no console, give up.
144 */
145 if (best_cp == NULL) {
146 if (cn_tab != NULL && cn_tab->cn_term != NULL)
147 (*cn_tab->cn_term)(cn_tab);
148 cn_tab = best_cp;
149 return;
150 }
151
152 /*
153 * Initialize console, then attach to it. This ordering allows
154 * debugging using the previous console, if any.
155 */
156 (*best_cp->cn_init)(best_cp);
157 if (cn_tab != NULL && cn_tab != best_cp) {
158 /* Turn off the previous console. */
159 if (cn_tab->cn_term != NULL)
160 (*cn_tab->cn_term)(cn_tab);
161 }
162 if (boothowto & RB_PAUSE)
163 console_pausing = 1;
164 cn_tab = best_cp;
165}
166
167void
168cninit_finish()
169{
170 struct cdevsw *cdp;
171
172 if ((cn_tab == NULL) || cn_mute)
173 return;
174
175 /*
176 * Hook the open and close functions.
177 */
178 cdp = devsw(cn_tab->cn_dev);
179 if (cdp != NULL) {
180 cn_phys_close = cdp->d_close;
181 cdp->d_close = cnclose;
182 cn_phys_open = cdp->d_open;
183 cdp->d_open = cnopen;
184 }
185 cn_dev_t = cn_tab->cn_dev;
186 cn_udev_t = dev2udev(cn_dev_t);
187 console_pausing = 0;
188}
189
190static void
191cnuninit(void)
192{
193 struct cdevsw *cdp;
194
195 if (cn_tab == NULL)
196 return;
197
198 /*
199 * Unhook the open and close functions.
200 */
201 cdp = devsw(cn_tab->cn_dev);
202 if (cdp != NULL) {
203 cdp->d_close = cn_phys_close;
204 cdp->d_open = cn_phys_open;
205 }
206 cn_phys_close = NULL;
207 cn_phys_open = NULL;
208 cn_dev_t = NODEV;
209 cn_udev_t = NOUDEV;
210}
211
212/*
213 * User has changed the state of the console muting.
214 * This may require us to open or close the device in question.
215 */
216static int
217sysctl_kern_consmute(SYSCTL_HANDLER_ARGS)
218{
219 int error;
220 int ocn_mute;
221
222 ocn_mute = cn_mute;
223 error = sysctl_handle_int(oidp, &cn_mute, 0, req);
224 if((error == 0) && (cn_tab != NULL) && (req->newptr != NULL)) {
225 if(ocn_mute && !cn_mute) {
226 /*
227 * going from muted to unmuted.. open the physical dev
228 * if the console has been openned
229 */
230 cninit_finish();
231 if(cn_is_open)
232 /* XXX curproc is not what we want really */
233 error = cnopen(cn_dev_t, openflag,
234 openmode, curproc);
235 /* if it failed, back it out */
236 if ( error != 0) cnuninit();
237 } else if (!ocn_mute && cn_mute) {
238 /*
239 * going from unmuted to muted.. close the physical dev
240 * if it's only open via /dev/console
241 */
242 if(cn_is_open)
243 error = cnclose(cn_dev_t, openflag,
244 openmode, curproc);
245 if ( error == 0) cnuninit();
246 }
247 if (error != 0) {
248 /*
249 * back out the change if there was an error
250 */
251 cn_mute = ocn_mute;
252 }
253 }
254 return (error);
255}
256
257SYSCTL_PROC(_kern, OID_AUTO, consmute, CTLTYPE_INT|CTLFLAG_RW,
258 0, sizeof cn_mute, sysctl_kern_consmute, "I", "");
259
260static int
261cnopen(dev, flag, mode, p)
262 dev_t dev;
263 int flag, mode;
264 struct proc *p;
265{
266 dev_t cndev, physdev;
267 int retval = 0;
268
269 if (cn_tab == NULL || cn_phys_open == NULL)
270 return (0);
271 cndev = cn_tab->cn_dev;
272 physdev = (major(dev) == major(cndev) ? dev : cndev);
273 /*
274 * If mute is active, then non console opens don't get here
275 * so we don't need to check for that. They
276 * bypass this and go straight to the device.
277 */
278 if(!cn_mute)
279 retval = (*cn_phys_open)(physdev, flag, mode, p);
280 if (retval == 0) {
281 /*
282 * check if we openned it via /dev/console or
283 * via the physical entry (e.g. /dev/sio0).
284 */
285 if (dev == cndev)
286 cn_phys_is_open = 1;
287 else if (physdev == cndev) {
288 openmode = mode;
289 openflag = flag;
290 cn_is_open = 1;
291 }
292 dev->si_tty = physdev->si_tty;
293 }
294 return (retval);
295}
296
297static int
298cnclose(dev, flag, mode, p)
299 dev_t dev;
300 int flag, mode;
301 struct proc *p;
302{
303 dev_t cndev;
304 struct tty *cn_tp;
305
306 if (cn_tab == NULL || cn_phys_open == NULL)
307 return (0);
308 cndev = cn_tab->cn_dev;
309 cn_tp = cndev->si_tty;
310 /*
311 * act appropriatly depending on whether it's /dev/console
312 * or the pysical device (e.g. /dev/sio) that's being closed.
313 * in either case, don't actually close the device unless
314 * both are closed.
315 */
316 if (dev == cndev) {
317 /* the physical device is about to be closed */
318 cn_phys_is_open = 0;
319 if (cn_is_open) {
320 if (cn_tp) {
321 /* perform a ttyhalfclose() */
322 /* reset session and proc group */
323 cn_tp->t_pgrp = NULL;
324 cn_tp->t_session = NULL;
325 }
326 return (0);
327 }
328 } else if (major(dev) != major(cndev)) {
329 /* the logical console is about to be closed */
330 cn_is_open = 0;
331 if (cn_phys_is_open)
332 return (0);
333 dev = cndev;
334 }
335 if(cn_phys_close)
336 return ((*cn_phys_close)(dev, flag, mode, p));
337 return (0);
338}
339
340static int
341cnread(dev, uio, flag)
342 dev_t dev;
343 struct uio *uio;
344 int flag;
345{
346
347 if (cn_tab == NULL || cn_phys_open == NULL)
348 return (0);
349 dev = cn_tab->cn_dev;
350 return ((*devsw(dev)->d_read)(dev, uio, flag));
351}
352
353static int
354cnwrite(dev, uio, flag)
355 dev_t dev;
356 struct uio *uio;
357 int flag;
358{
359
360 if (cn_tab == NULL || cn_phys_open == NULL) {
361 uio->uio_resid = 0; /* dump the data */
362 return (0);
363 }
364 if (constty)
365 dev = constty->t_dev;
366 else
367 dev = cn_tab->cn_dev;
368 log_console(uio);
369 return ((*devsw(dev)->d_write)(dev, uio, flag));
370}
371
372static int
373cnioctl(dev, cmd, data, flag, p)
374 dev_t dev;
375 u_long cmd;
376 caddr_t data;
377 int flag;
378 struct proc *p;
379{
380 int error;
381
382 if (cn_tab == NULL || cn_phys_open == NULL)
383 return (0);
384 /*
385 * Superuser can always use this to wrest control of console
386 * output from the "virtual" console.
387 */
388 if (cmd == TIOCCONS && constty) {
389 error = suser(p);
390 if (error)
391 return (error);
392 constty = NULL;
393 return (0);
394 }
395 dev = cn_tab->cn_dev;
396 return ((*devsw(dev)->d_ioctl)(dev, cmd, data, flag, p));
397}
398
399static int
400cnpoll(dev, events, p)
401 dev_t dev;
402 int events;
403 struct proc *p;
404{
405 if ((cn_tab == NULL) || cn_mute)
406 return (1);
407
408 dev = cn_tab->cn_dev;
409
410 return ((*devsw(dev)->d_poll)(dev, events, p));
411}
412
413static int
414cnkqfilter(dev, kn)
415 dev_t dev;
416 struct knote *kn;
417{
418 if ((cn_tab == NULL) || cn_mute)
419 return (1);
420
421 dev = cn_tab->cn_dev;
422 if (devsw(dev)->d_flags & D_KQFILTER)
423 return ((*devsw(dev)->d_kqfilter)(dev, kn));
424 return (1);
425}
426
427int
428cngetc()
429{
430 int c;
431 if ((cn_tab == NULL) || cn_mute)
432 return (-1);
433 c = (*cn_tab->cn_getc)(cn_tab->cn_dev);
434 if (c == '\r') c = '\n'; /* console input is always ICRNL */
435 return (c);
436}
437
438int
439cncheckc()
440{
441 if ((cn_tab == NULL) || cn_mute)
442 return (-1);
443 return ((*cn_tab->cn_checkc)(cn_tab->cn_dev));
444}
445
446void
447cnputc(c)
448 register int c;
449{
450 char *cp;
451
452 if ((cn_tab == NULL) || cn_mute)
453 return;
454 if (c) {
455 if (c == '\n')
456 (*cn_tab->cn_putc)(cn_tab->cn_dev, '\r');
457 (*cn_tab->cn_putc)(cn_tab->cn_dev, c);
458#ifdef DDB
459 if (console_pausing && !db_active && (c == '\n')) {
460#else
461 if (console_pausing && (c == '\n')) {
462#endif
463 for(cp=console_pausestr; *cp != '\0'; cp++)
464 (*cn_tab->cn_putc)(cn_tab->cn_dev, *cp);
465 if (cngetc() == '.')
466 console_pausing = 0;
467 (*cn_tab->cn_putc)(cn_tab->cn_dev, '\r');
468 for(cp=console_pausestr; *cp != '\0'; cp++)
469 (*cn_tab->cn_putc)(cn_tab->cn_dev, ' ');
470 (*cn_tab->cn_putc)(cn_tab->cn_dev, '\r');
471 }
472 }
473}
474
475void
476cndbctl(on)
477 int on;
478{
479 static int refcount;
480
481 if (cn_tab == NULL)
482 return;
483 if (!on)
484 refcount--;
485 if (refcount == 0 && cn_tab->cn_dbctl != NULL)
486 (*cn_tab->cn_dbctl)(cn_tab->cn_dev, on);
487 if (on)
488 refcount++;
489}
490
491static void
492cn_drvinit(void *unused)
493{
494
495 cn_devfsdev = make_dev(&cn_cdevsw, 0, UID_ROOT, GID_WHEEL, 0600,
496 "console");
497}
498
499SYSINIT(cndev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR,cn_drvinit,NULL)