xref: /dflybsd-src/sys/kern/tty_pty.c (revision 97fecd825dd1a70c628493b90a9b1b1724f151df)
1 /*
2  * Copyright (c) 1982, 1986, 1989, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  *	@(#)tty_pty.c	8.4 (Berkeley) 2/20/95
34  * $FreeBSD: src/sys/kern/tty_pty.c,v 1.74.2.4 2002/02/20 19:58:13 dillon Exp $
35  * $DragonFly: src/sys/kern/tty_pty.c,v 1.21 2008/08/13 10:29:38 swildner Exp $
36  */
37 
38 /*
39  * Pseudo-teletype Driver
40  * (Actually two drivers, requiring two dev_ops structures)
41  */
42 #include "use_pty.h"		/* XXX */
43 #include "opt_compat.h"
44 
45 #include <sys/param.h>
46 #include <sys/systm.h>
47 #if defined(COMPAT_43) || defined(COMPAT_SUNOS)
48 #include <sys/ioctl_compat.h>
49 #endif
50 #include <sys/proc.h>
51 #include <sys/priv.h>
52 #include <sys/tty.h>
53 #include <sys/conf.h>
54 #include <sys/fcntl.h>
55 #include <sys/poll.h>
56 #include <sys/kernel.h>
57 #include <sys/vnode.h>
58 #include <sys/signalvar.h>
59 #include <sys/malloc.h>
60 #include <sys/device.h>
61 #include <sys/thread2.h>
62 
63 MALLOC_DEFINE(M_PTY, "ptys", "pty data structures");
64 
65 static void ptsstart (struct tty *tp);
66 static void ptsstop (struct tty *tp, int rw);
67 static void ptcwakeup (struct tty *tp, int flag);
68 static void ptyinit (int n);
69 
70 static	d_open_t	ptsopen;
71 static	d_close_t	ptsclose;
72 static	d_read_t	ptsread;
73 static	d_write_t	ptswrite;
74 static	d_ioctl_t	ptyioctl;
75 static	d_open_t	ptcopen;
76 static	d_close_t	ptcclose;
77 static	d_read_t	ptcread;
78 static	d_write_t	ptcwrite;
79 static	d_poll_t	ptcpoll;
80 
81 #define	CDEV_MAJOR_S	5
82 static struct dev_ops pts_ops = {
83 	{ "pts", CDEV_MAJOR_S, D_TTY | D_KQFILTER },
84 	.d_open =	ptsopen,
85 	.d_close =	ptsclose,
86 	.d_read =	ptsread,
87 	.d_write =	ptswrite,
88 	.d_ioctl =	ptyioctl,
89 	.d_poll =	ttypoll,
90 	.d_kqfilter =	ttykqfilter
91 };
92 
93 #define	CDEV_MAJOR_C	6
94 static struct dev_ops ptc_ops = {
95 	{ "ptc", CDEV_MAJOR_C, D_TTY | D_KQFILTER | D_MASTER },
96 	.d_open =	ptcopen,
97 	.d_close =	ptcclose,
98 	.d_read =	ptcread,
99 	.d_write =	ptcwrite,
100 	.d_ioctl =	ptyioctl,
101 	.d_poll =	ptcpoll,
102 	.d_kqfilter =	ttykqfilter
103 };
104 
105 #define BUFSIZ 100		/* Chunk size iomoved to/from user */
106 
107 struct	pt_ioctl {
108 	int	pt_flags;
109 	struct	selinfo pt_selr, pt_selw;
110 	u_char	pt_send;
111 	u_char	pt_ucntl;
112 	struct tty pt_tty;
113 	cdev_t	devs, devc;
114 	struct	prison *pt_prison;
115 };
116 
117 #define	PF_PKT		0x08		/* packet mode */
118 #define	PF_STOPPED	0x10		/* user told stopped */
119 #define	PF_REMOTE	0x20		/* remote and flow controlled input */
120 #define	PF_NOSTOP	0x40
121 #define PF_UCNTL	0x80		/* user control mode */
122 
123 /*
124  * This function creates and initializes a pts/ptc pair
125  *
126  * pts == /dev/tty[pqrsPQRS][0123456789abcdefghijklmnopqrstuv]
127  * ptc == /dev/pty[pqrsPQRS][0123456789abcdefghijklmnopqrstuv]
128  *
129  * XXX: define and add mapping of upper minor bits to allow more
130  *      than 256 ptys.
131  */
132 static void
133 ptyinit(int n)
134 {
135 	cdev_t devs, devc;
136 	char *names = "pqrsPQRS";
137 	struct pt_ioctl *pt;
138 
139 	/* For now we only map the lower 8 bits of the minor */
140 	if (n & ~0xff)
141 		return;
142 
143 	pt = kmalloc(sizeof(*pt), M_PTY, M_WAITOK | M_ZERO);
144 	pt->devs = devs = make_dev(&pts_ops, n,
145 	    0, 0, 0666, "tty%c%r", names[n / 32], n % 32);
146 	pt->devc = devc = make_dev(&ptc_ops, n,
147 	    0, 0, 0666, "pty%c%r", names[n / 32], n % 32);
148 
149 	devs->si_drv1 = devc->si_drv1 = pt;
150 	devs->si_tty = devc->si_tty = &pt->pt_tty;
151 	pt->pt_tty.t_dev = devs;
152 	ttyregister(&pt->pt_tty);
153 }
154 
155 /*ARGSUSED*/
156 static	int
157 ptsopen(struct dev_open_args *ap)
158 {
159 	cdev_t dev = ap->a_head.a_dev;
160 	struct tty *tp;
161 	int error;
162 #if 0
163 	int minr;
164 	cdev_t nextdev;
165 #endif
166 	struct pt_ioctl *pti;
167 
168 #if 0
169 	minr = lminor(dev);
170 	/*
171 	 * REMOVED gross hack for devfs.  also note that makedev()
172 	 * no longer exists in this form and reference counting makes
173 	 * this a problem if we don't clean it out later.
174 	 */
175 	if (minr < 255) {
176 		nextdev = make_sub_dev(dev, minr + 1);
177 		if (!nextdev->si_drv1) {
178 			ptyinit(minr + 1);
179 		}
180 	}
181 #endif
182 	if (!dev->si_drv1)
183 		ptyinit(minor(dev));
184 	if (!dev->si_drv1)
185 		return(ENXIO);
186 	pti = dev->si_drv1;
187 	tp = dev->si_tty;
188 	if ((tp->t_state & TS_ISOPEN) == 0) {
189 		ttychars(tp);		/* Set up default chars */
190 		tp->t_iflag = TTYDEF_IFLAG;
191 		tp->t_oflag = TTYDEF_OFLAG;
192 		tp->t_lflag = TTYDEF_LFLAG;
193 		tp->t_cflag = TTYDEF_CFLAG;
194 		tp->t_ispeed = tp->t_ospeed = TTYDEF_SPEED;
195 	} else if ((tp->t_state & TS_XCLUDE) && priv_check_cred(ap->a_cred, PRIV_ROOT, 0)) {
196 		return (EBUSY);
197 	} else if (pti->pt_prison != ap->a_cred->cr_prison) {
198 		return (EBUSY);
199 	}
200 	if (tp->t_oproc)			/* Ctrlr still around. */
201 		(void)(*linesw[tp->t_line].l_modem)(tp, 1);
202 	while ((tp->t_state & TS_CARR_ON) == 0) {
203 		if (ap->a_oflags & FNONBLOCK)
204 			break;
205 		error = ttysleep(tp, TSA_CARR_ON(tp), PCATCH, "ptsopn", 0);
206 		if (error)
207 			return (error);
208 	}
209 	error = (*linesw[tp->t_line].l_open)(dev, tp);
210 	if (error == 0)
211 		ptcwakeup(tp, FREAD|FWRITE);
212 	return (error);
213 }
214 
215 static	int
216 ptsclose(struct dev_close_args *ap)
217 {
218 	cdev_t dev = ap->a_head.a_dev;
219 	struct tty *tp;
220 	int err;
221 
222 	tp = dev->si_tty;
223 	err = (*linesw[tp->t_line].l_close)(tp, ap->a_fflag);
224 	ptsstop(tp, FREAD|FWRITE);
225 	(void) ttyclose(tp);
226 	return (err);
227 }
228 
229 static	int
230 ptsread(struct dev_read_args *ap)
231 {
232 	cdev_t dev = ap->a_head.a_dev;
233 	struct proc *p = curproc;
234 	struct tty *tp = dev->si_tty;
235 	struct pt_ioctl *pti = dev->si_drv1;
236 	struct lwp *lp;
237 
238 	int error = 0;
239 
240 	lp = curthread->td_lwp;
241 
242 again:
243 	if (pti->pt_flags & PF_REMOTE) {
244 		while (isbackground(p, tp)) {
245 			if (SIGISMEMBER(p->p_sigignore, SIGTTIN) ||
246 			    SIGISMEMBER(lp->lwp_sigmask, SIGTTIN) ||
247 			    p->p_pgrp->pg_jobc == 0 || p->p_flag & P_PPWAIT)
248 				return (EIO);
249 			pgsignal(p->p_pgrp, SIGTTIN, 1);
250 			error = ttysleep(tp, &lbolt, PCATCH, "ptsbg", 0);
251 			if (error)
252 				return (error);
253 		}
254 		if (tp->t_canq.c_cc == 0) {
255 			if (ap->a_ioflag & IO_NDELAY)
256 				return (EWOULDBLOCK);
257 			error = ttysleep(tp, TSA_PTS_READ(tp), PCATCH,
258 					 "ptsin", 0);
259 			if (error)
260 				return (error);
261 			goto again;
262 		}
263 		while (tp->t_canq.c_cc > 1 && ap->a_uio->uio_resid > 0)
264 			if (ureadc(clist_getc(&tp->t_canq), ap->a_uio) < 0) {
265 				error = EFAULT;
266 				break;
267 			}
268 		if (tp->t_canq.c_cc == 1)
269 			clist_getc(&tp->t_canq);
270 		if (tp->t_canq.c_cc)
271 			return (error);
272 	} else
273 		if (tp->t_oproc)
274 			error = (*linesw[tp->t_line].l_read)(tp, ap->a_uio, ap->a_ioflag);
275 	ptcwakeup(tp, FWRITE);
276 	return (error);
277 }
278 
279 /*
280  * Write to pseudo-tty.
281  * Wakeups of controlling tty will happen
282  * indirectly, when tty driver calls ptsstart.
283  */
284 static	int
285 ptswrite(struct dev_write_args *ap)
286 {
287 	cdev_t dev = ap->a_head.a_dev;
288 	struct tty *tp;
289 
290 	tp = dev->si_tty;
291 	if (tp->t_oproc == 0)
292 		return (EIO);
293 	return ((*linesw[tp->t_line].l_write)(tp, ap->a_uio, ap->a_ioflag));
294 }
295 
296 /*
297  * Start output on pseudo-tty.
298  * Wake up process selecting or sleeping for input from controlling tty.
299  */
300 static void
301 ptsstart(struct tty *tp)
302 {
303 	struct pt_ioctl *pti = tp->t_dev->si_drv1;
304 
305 	if (tp->t_state & TS_TTSTOP)
306 		return;
307 	if (pti->pt_flags & PF_STOPPED) {
308 		pti->pt_flags &= ~PF_STOPPED;
309 		pti->pt_send = TIOCPKT_START;
310 	}
311 	ptcwakeup(tp, FREAD);
312 }
313 
314 static void
315 ptcwakeup(struct tty *tp, int flag)
316 {
317 	struct pt_ioctl *pti = tp->t_dev->si_drv1;
318 
319 	if (flag & FREAD) {
320 		selwakeup(&pti->pt_selr);
321 		wakeup(TSA_PTC_READ(tp));
322 	}
323 	if (flag & FWRITE) {
324 		selwakeup(&pti->pt_selw);
325 		wakeup(TSA_PTC_WRITE(tp));
326 	}
327 }
328 
329 static	int
330 ptcopen(struct dev_open_args *ap)
331 {
332 	cdev_t dev = ap->a_head.a_dev;
333 	struct tty *tp;
334 	struct pt_ioctl *pti;
335 
336 	if (!dev->si_drv1)
337 		ptyinit(minor(dev));
338 	if (!dev->si_drv1)
339 		return(ENXIO);
340 	tp = dev->si_tty;
341 	if (tp->t_oproc)
342 		return (EIO);
343 	tp->t_oproc = ptsstart;
344 	tp->t_stop = ptsstop;
345 	(void)(*linesw[tp->t_line].l_modem)(tp, 1);
346 	tp->t_lflag &= ~EXTPROC;
347 	pti = dev->si_drv1;
348 	pti->pt_prison = ap->a_cred->cr_prison;
349 	pti->pt_flags = 0;
350 	pti->pt_send = 0;
351 	pti->pt_ucntl = 0;
352 	pti->devs->si_uid = ap->a_cred->cr_uid;
353 	return (0);
354 }
355 
356 static	int
357 ptcclose(struct dev_close_args *ap)
358 {
359 	cdev_t dev = ap->a_head.a_dev;
360 	struct tty *tp;
361 
362 	tp = dev->si_tty;
363 	(void)(*linesw[tp->t_line].l_modem)(tp, 0);
364 
365 	/*
366 	 * XXX MDMBUF makes no sense for ptys but would inhibit the above
367 	 * l_modem().  CLOCAL makes sense but isn't supported.   Special
368 	 * l_modem()s that ignore carrier drop make no sense for ptys but
369 	 * may be in use because other parts of the line discipline make
370 	 * sense for ptys.  Recover by doing everything that a normal
371 	 * ttymodem() would have done except for sending a SIGHUP.
372 	 */
373 	if (tp->t_state & TS_ISOPEN) {
374 		tp->t_state &= ~(TS_CARR_ON | TS_CONNECTED);
375 		tp->t_state |= TS_ZOMBIE;
376 		ttyflush(tp, FREAD | FWRITE);
377 		tp->t_dev->si_uid = 0;
378 	}
379 
380 	tp->t_oproc = 0;		/* mark closed */
381 	return (0);
382 }
383 
384 static	int
385 ptcread(struct dev_read_args *ap)
386 {
387 	cdev_t dev = ap->a_head.a_dev;
388 	struct tty *tp = dev->si_tty;
389 	struct pt_ioctl *pti = dev->si_drv1;
390 	char buf[BUFSIZ];
391 	int error = 0, cc;
392 
393 	/*
394 	 * We want to block until the slave
395 	 * is open, and there's something to read;
396 	 * but if we lost the slave or we're NBIO,
397 	 * then return the appropriate error instead.
398 	 */
399 	for (;;) {
400 		if (tp->t_state&TS_ISOPEN) {
401 			if (pti->pt_flags&PF_PKT && pti->pt_send) {
402 				error = ureadc((int)pti->pt_send, ap->a_uio);
403 				if (error)
404 					return (error);
405 				if (pti->pt_send & TIOCPKT_IOCTL) {
406 					cc = min(ap->a_uio->uio_resid,
407 						sizeof(tp->t_termios));
408 					uiomove((caddr_t)&tp->t_termios, cc,
409 						ap->a_uio);
410 				}
411 				pti->pt_send = 0;
412 				return (0);
413 			}
414 			if (pti->pt_flags&PF_UCNTL && pti->pt_ucntl) {
415 				error = ureadc((int)pti->pt_ucntl, ap->a_uio);
416 				if (error)
417 					return (error);
418 				pti->pt_ucntl = 0;
419 				return (0);
420 			}
421 			if (tp->t_outq.c_cc && (tp->t_state&TS_TTSTOP) == 0)
422 				break;
423 		}
424 		if ((tp->t_state & TS_CONNECTED) == 0)
425 			return (0);	/* EOF */
426 		if (ap->a_ioflag & IO_NDELAY)
427 			return (EWOULDBLOCK);
428 		error = tsleep(TSA_PTC_READ(tp), PCATCH, "ptcin", 0);
429 		if (error)
430 			return (error);
431 	}
432 	if (pti->pt_flags & (PF_PKT|PF_UCNTL))
433 		error = ureadc(0, ap->a_uio);
434 	while (ap->a_uio->uio_resid > 0 && error == 0) {
435 		cc = q_to_b(&tp->t_outq, buf, min(ap->a_uio->uio_resid, BUFSIZ));
436 		if (cc <= 0)
437 			break;
438 		error = uiomove(buf, cc, ap->a_uio);
439 	}
440 	ttwwakeup(tp);
441 	return (error);
442 }
443 
444 static	void
445 ptsstop(struct tty *tp, int flush)
446 {
447 	struct pt_ioctl *pti = tp->t_dev->si_drv1;
448 	int flag;
449 
450 	/* note: FLUSHREAD and FLUSHWRITE already ok */
451 	if (flush == 0) {
452 		flush = TIOCPKT_STOP;
453 		pti->pt_flags |= PF_STOPPED;
454 	} else
455 		pti->pt_flags &= ~PF_STOPPED;
456 	pti->pt_send |= flush;
457 	/* change of perspective */
458 	flag = 0;
459 	if (flush & FREAD)
460 		flag |= FWRITE;
461 	if (flush & FWRITE)
462 		flag |= FREAD;
463 	ptcwakeup(tp, flag);
464 }
465 
466 static	int
467 ptcpoll(struct dev_poll_args *ap)
468 {
469 	cdev_t dev = ap->a_head.a_dev;
470 	struct tty *tp = dev->si_tty;
471 	struct pt_ioctl *pti = dev->si_drv1;
472 	int revents = 0;
473 
474 	if ((tp->t_state & TS_CONNECTED) == 0) {
475 		ap->a_events = seltrue(dev, ap->a_events) | POLLHUP;
476 		return(0);
477 	}
478 
479 	/*
480 	 * Need to block timeouts (ttrstart).
481 	 */
482 	crit_enter();
483 
484 	if (ap->a_events & (POLLIN | POLLRDNORM))
485 		if ((tp->t_state & TS_ISOPEN) &&
486 		    ((tp->t_outq.c_cc && (tp->t_state & TS_TTSTOP) == 0) ||
487 		     ((pti->pt_flags & PF_PKT) && pti->pt_send) ||
488 		     ((pti->pt_flags & PF_UCNTL) && pti->pt_ucntl)))
489 			revents |= ap->a_events & (POLLIN | POLLRDNORM);
490 
491 	if (ap->a_events & (POLLOUT | POLLWRNORM))
492 		if (tp->t_state & TS_ISOPEN &&
493 		    ((pti->pt_flags & PF_REMOTE) ?
494 		     (tp->t_canq.c_cc == 0) :
495 		     ((tp->t_rawq.c_cc + tp->t_canq.c_cc < TTYHOG - 2) ||
496 		      (tp->t_canq.c_cc == 0 && (tp->t_lflag & ICANON)))))
497 			revents |= ap->a_events & (POLLOUT | POLLWRNORM);
498 
499 	if (ap->a_events & POLLHUP)
500 		if ((tp->t_state & TS_CARR_ON) == 0)
501 			revents |= POLLHUP;
502 
503 	if (revents == 0) {
504 		if (ap->a_events & (POLLIN | POLLRDNORM))
505 			selrecord(curthread, &pti->pt_selr);
506 
507 		if (ap->a_events & (POLLOUT | POLLWRNORM))
508 			selrecord(curthread, &pti->pt_selw);
509 	}
510 	crit_exit();
511 
512 	ap->a_events = revents;
513 	return (0);
514 }
515 
516 static	int
517 ptcwrite(struct dev_write_args *ap)
518 {
519 	cdev_t dev = ap->a_head.a_dev;
520 	struct tty *tp = dev->si_tty;
521 	u_char *cp = 0;
522 	int cc = 0;
523 	u_char locbuf[BUFSIZ];
524 	int cnt = 0;
525 	struct pt_ioctl *pti = dev->si_drv1;
526 	int error = 0;
527 
528 again:
529 	if ((tp->t_state&TS_ISOPEN) == 0)
530 		goto block;
531 	if (pti->pt_flags & PF_REMOTE) {
532 		if (tp->t_canq.c_cc)
533 			goto block;
534 		while ((ap->a_uio->uio_resid > 0 || cc > 0) &&
535 		       tp->t_canq.c_cc < TTYHOG - 1) {
536 			if (cc == 0) {
537 				cc = min(ap->a_uio->uio_resid, BUFSIZ);
538 				cc = min(cc, TTYHOG - 1 - tp->t_canq.c_cc);
539 				cp = locbuf;
540 				error = uiomove((caddr_t)cp, cc, ap->a_uio);
541 				if (error)
542 					return (error);
543 				/* check again for safety */
544 				if ((tp->t_state & TS_ISOPEN) == 0) {
545 					/* adjust as usual */
546 					ap->a_uio->uio_resid += cc;
547 					return (EIO);
548 				}
549 			}
550 			if (cc > 0) {
551 				cc = b_to_q((char *)cp, cc, &tp->t_canq);
552 				/*
553 				 * XXX we don't guarantee that the canq size
554 				 * is >= TTYHOG, so the above b_to_q() may
555 				 * leave some bytes uncopied.  However, space
556 				 * is guaranteed for the null terminator if
557 				 * we don't fail here since (TTYHOG - 1) is
558 				 * not a multiple of CBSIZE.
559 				 */
560 				if (cc > 0)
561 					break;
562 			}
563 		}
564 		/* adjust for data copied in but not written */
565 		ap->a_uio->uio_resid += cc;
566 		clist_putc(0, &tp->t_canq);
567 		ttwakeup(tp);
568 		wakeup(TSA_PTS_READ(tp));
569 		return (0);
570 	}
571 	while (ap->a_uio->uio_resid > 0 || cc > 0) {
572 		if (cc == 0) {
573 			cc = min(ap->a_uio->uio_resid, BUFSIZ);
574 			cp = locbuf;
575 			error = uiomove((caddr_t)cp, cc, ap->a_uio);
576 			if (error)
577 				return (error);
578 			/* check again for safety */
579 			if ((tp->t_state & TS_ISOPEN) == 0) {
580 				/* adjust for data copied in but not written */
581 				ap->a_uio->uio_resid += cc;
582 				return (EIO);
583 			}
584 		}
585 		while (cc > 0) {
586 			if ((tp->t_rawq.c_cc + tp->t_canq.c_cc) >= TTYHOG - 2 &&
587 			   (tp->t_canq.c_cc > 0 || !(tp->t_lflag&ICANON))) {
588 				wakeup(TSA_HUP_OR_INPUT(tp));
589 				goto block;
590 			}
591 			(*linesw[tp->t_line].l_rint)(*cp++, tp);
592 			cnt++;
593 			cc--;
594 		}
595 		cc = 0;
596 	}
597 	return (0);
598 block:
599 	/*
600 	 * Come here to wait for slave to open, for space
601 	 * in outq, or space in rawq, or an empty canq.
602 	 */
603 	if ((tp->t_state & TS_CONNECTED) == 0) {
604 		/* adjust for data copied in but not written */
605 		ap->a_uio->uio_resid += cc;
606 		return (EIO);
607 	}
608 	if (ap->a_ioflag & IO_NDELAY) {
609 		/* adjust for data copied in but not written */
610 		ap->a_uio->uio_resid += cc;
611 		if (cnt == 0)
612 			return (EWOULDBLOCK);
613 		return (0);
614 	}
615 	error = tsleep(TSA_PTC_WRITE(tp), PCATCH, "ptcout", 0);
616 	if (error) {
617 		/* adjust for data copied in but not written */
618 		ap->a_uio->uio_resid += cc;
619 		return (error);
620 	}
621 	goto again;
622 }
623 
624 /*ARGSUSED*/
625 static	int
626 ptyioctl(struct dev_ioctl_args *ap)
627 {
628 	cdev_t dev = ap->a_head.a_dev;
629 	struct tty *tp = dev->si_tty;
630 	struct pt_ioctl *pti = dev->si_drv1;
631 	u_char *cc = tp->t_cc;
632 	int stop, error;
633 
634 	if (dev_dflags(dev) & D_MASTER) {
635 		switch (ap->a_cmd) {
636 
637 		case TIOCGPGRP:
638 			/*
639 			 * We avoid calling ttioctl on the controller since,
640 			 * in that case, tp must be the controlling terminal.
641 			 */
642 			*(int *)ap->a_data = tp->t_pgrp ? tp->t_pgrp->pg_id : 0;
643 			return (0);
644 
645 		case TIOCPKT:
646 			if (*(int *)ap->a_data) {
647 				if (pti->pt_flags & PF_UCNTL)
648 					return (EINVAL);
649 				pti->pt_flags |= PF_PKT;
650 			} else
651 				pti->pt_flags &= ~PF_PKT;
652 			return (0);
653 
654 		case TIOCUCNTL:
655 			if (*(int *)ap->a_data) {
656 				if (pti->pt_flags & PF_PKT)
657 					return (EINVAL);
658 				pti->pt_flags |= PF_UCNTL;
659 			} else
660 				pti->pt_flags &= ~PF_UCNTL;
661 			return (0);
662 
663 		case TIOCREMOTE:
664 			if (*(int *)ap->a_data)
665 				pti->pt_flags |= PF_REMOTE;
666 			else
667 				pti->pt_flags &= ~PF_REMOTE;
668 			ttyflush(tp, FREAD|FWRITE);
669 			return (0);
670 		}
671 
672 		/*
673 		 * The rest of the ioctls shouldn't be called until
674 		 * the slave is open.
675 		 */
676 		if ((tp->t_state & TS_ISOPEN) == 0)
677 			return (EAGAIN);
678 
679 		switch (ap->a_cmd) {
680 #ifdef COMPAT_43
681 		case TIOCSETP:
682 		case TIOCSETN:
683 #endif
684 		case TIOCSETD:
685 		case TIOCSETA:
686 		case TIOCSETAW:
687 		case TIOCSETAF:
688 			/*
689 			 * IF CONTROLLER STTY THEN MUST FLUSH TO PREVENT A HANG.
690 			 * ttywflush(tp) will hang if there are characters in
691 			 * the outq.
692 			 */
693 			ndflush(&tp->t_outq, tp->t_outq.c_cc);
694 			break;
695 
696 		case TIOCSIG:
697 			if (*(unsigned int *)ap->a_data >= NSIG ||
698 			    *(unsigned int *)ap->a_data == 0)
699 				return(EINVAL);
700 			if ((tp->t_lflag&NOFLSH) == 0)
701 				ttyflush(tp, FREAD|FWRITE);
702 			pgsignal(tp->t_pgrp, *(unsigned int *)ap->a_data, 1);
703 			if ((*(unsigned int *)ap->a_data == SIGINFO) &&
704 			    ((tp->t_lflag&NOKERNINFO) == 0))
705 				ttyinfo(tp);
706 			return(0);
707 		}
708 	}
709 	if (ap->a_cmd == TIOCEXT) {
710 		/*
711 		 * When the EXTPROC bit is being toggled, we need
712 		 * to send an TIOCPKT_IOCTL if the packet driver
713 		 * is turned on.
714 		 */
715 		if (*(int *)ap->a_data) {
716 			if (pti->pt_flags & PF_PKT) {
717 				pti->pt_send |= TIOCPKT_IOCTL;
718 				ptcwakeup(tp, FREAD);
719 			}
720 			tp->t_lflag |= EXTPROC;
721 		} else {
722 			if ((tp->t_lflag & EXTPROC) &&
723 			    (pti->pt_flags & PF_PKT)) {
724 				pti->pt_send |= TIOCPKT_IOCTL;
725 				ptcwakeup(tp, FREAD);
726 			}
727 			tp->t_lflag &= ~EXTPROC;
728 		}
729 		return(0);
730 	}
731 	error = (*linesw[tp->t_line].l_ioctl)(tp, ap->a_cmd, ap->a_data,
732 					      ap->a_fflag, ap->a_cred);
733 	if (error == ENOIOCTL)
734 		 error = ttioctl(tp, ap->a_cmd, ap->a_data, ap->a_fflag);
735 	if (error == ENOIOCTL) {
736 		if (pti->pt_flags & PF_UCNTL &&
737 		    (ap->a_cmd & ~0xff) == UIOCCMD(0)) {
738 			if (ap->a_cmd & 0xff) {
739 				pti->pt_ucntl = (u_char)ap->a_cmd;
740 				ptcwakeup(tp, FREAD);
741 			}
742 			return (0);
743 		}
744 		error = ENOTTY;
745 	}
746 	/*
747 	 * If external processing and packet mode send ioctl packet.
748 	 */
749 	if ((tp->t_lflag&EXTPROC) && (pti->pt_flags & PF_PKT)) {
750 		switch(ap->a_cmd) {
751 		case TIOCSETA:
752 		case TIOCSETAW:
753 		case TIOCSETAF:
754 #ifdef COMPAT_43
755 		case TIOCSETP:
756 		case TIOCSETN:
757 #endif
758 #if defined(COMPAT_43) || defined(COMPAT_SUNOS)
759 		case TIOCSETC:
760 		case TIOCSLTC:
761 		case TIOCLBIS:
762 		case TIOCLBIC:
763 		case TIOCLSET:
764 #endif
765 			pti->pt_send |= TIOCPKT_IOCTL;
766 			ptcwakeup(tp, FREAD);
767 		default:
768 			break;
769 		}
770 	}
771 	stop = (tp->t_iflag & IXON) && CCEQ(cc[VSTOP], CTRL('s'))
772 		&& CCEQ(cc[VSTART], CTRL('q'));
773 	if (pti->pt_flags & PF_NOSTOP) {
774 		if (stop) {
775 			pti->pt_send &= ~TIOCPKT_NOSTOP;
776 			pti->pt_send |= TIOCPKT_DOSTOP;
777 			pti->pt_flags &= ~PF_NOSTOP;
778 			ptcwakeup(tp, FREAD);
779 		}
780 	} else {
781 		if (!stop) {
782 			pti->pt_send &= ~TIOCPKT_DOSTOP;
783 			pti->pt_send |= TIOCPKT_NOSTOP;
784 			pti->pt_flags |= PF_NOSTOP;
785 			ptcwakeup(tp, FREAD);
786 		}
787 	}
788 	return (error);
789 }
790 
791 
792 static void ptc_drvinit (void *unused);
793 
794 static void
795 ptc_drvinit(void *unused)
796 {
797 	dev_ops_add(&pts_ops, 0, 0);
798 	dev_ops_add(&ptc_ops, 0, 0);
799 	/* XXX: Gross hack for DEVFS */
800 	/* XXX: DEVFS is no more, should this be removed? */
801 	ptyinit(0);
802 }
803 
804 SYSINIT(ptcdev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR_C,ptc_drvinit,NULL)
805