xref: /dragonfly/sys/kern/tty_pty.c (revision b40e316c)
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 1.12 2004/05/19 22:52:58 dillon Exp $
36  */
37 
38 /*
39  * Pseudo-teletype Driver
40  * (Actually two drivers, requiring two entries in 'cdevsw')
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/tty.h>
52 #include <sys/conf.h>
53 #include <sys/fcntl.h>
54 #include <sys/poll.h>
55 #include <sys/kernel.h>
56 #include <sys/vnode.h>
57 #include <sys/signalvar.h>
58 #include <sys/malloc.h>
59 #include <sys/device.h>
60 
61 MALLOC_DEFINE(M_PTY, "ptys", "pty data structures");
62 
63 static void ptsstart (struct tty *tp);
64 static void ptsstop (struct tty *tp, int rw);
65 static void ptcwakeup (struct tty *tp, int flag);
66 static void ptyinit (int n);
67 
68 static	d_open_t	ptsopen;
69 static	d_close_t	ptsclose;
70 static	d_read_t	ptsread;
71 static	d_write_t	ptswrite;
72 static	d_ioctl_t	ptyioctl;
73 static	d_open_t	ptcopen;
74 static	d_close_t	ptcclose;
75 static	d_read_t	ptcread;
76 static	d_write_t	ptcwrite;
77 static	d_poll_t	ptcpoll;
78 
79 #define	CDEV_MAJOR_S	5
80 static struct cdevsw pts_cdevsw = {
81 	/* name */	"pts",
82 	/* maj */	CDEV_MAJOR_S,
83 	/* flags */	D_TTY | D_KQFILTER,
84 	/* port */	NULL,
85 	/* clone */	NULL,
86 
87 	/* open */	ptsopen,
88 	/* close */	ptsclose,
89 	/* read */	ptsread,
90 	/* write */	ptswrite,
91 	/* ioctl */	ptyioctl,
92 	/* poll */	ttypoll,
93 	/* mmap */	nommap,
94 	/* strategy */	nostrategy,
95 	/* dump */	nodump,
96 	/* psize */	nopsize,
97 	/* kqfilter */	ttykqfilter
98 };
99 
100 #define	CDEV_MAJOR_C	6
101 static struct cdevsw ptc_cdevsw = {
102 	/* name */	"ptc",
103 	/* maj */	CDEV_MAJOR_C,
104 	/* flags */	D_TTY | D_KQFILTER | D_MASTER,
105 	/* port */	NULL,
106 	/* clone */	NULL,
107 
108 	/* open */	ptcopen,
109 	/* close */	ptcclose,
110 	/* read */	ptcread,
111 	/* write */	ptcwrite,
112 	/* ioctl */	ptyioctl,
113 	/* poll */	ptcpoll,
114 	/* mmap */	nommap,
115 	/* strategy */	nostrategy,
116 	/* dump */	nodump,
117 	/* psize */	nopsize,
118 	/* kqfilter */	ttykqfilter
119 };
120 
121 #define BUFSIZ 100		/* Chunk size iomoved to/from user */
122 
123 struct	pt_ioctl {
124 	int	pt_flags;
125 	struct	selinfo pt_selr, pt_selw;
126 	u_char	pt_send;
127 	u_char	pt_ucntl;
128 	struct tty pt_tty;
129 	dev_t	devs, devc;
130 	struct	prison *pt_prison;
131 };
132 
133 #define	PF_PKT		0x08		/* packet mode */
134 #define	PF_STOPPED	0x10		/* user told stopped */
135 #define	PF_REMOTE	0x20		/* remote and flow controlled input */
136 #define	PF_NOSTOP	0x40
137 #define PF_UCNTL	0x80		/* user control mode */
138 
139 /*
140  * This function creates and initializes a pts/ptc pair
141  *
142  * pts == /dev/tty[pqrsPQRS][0123456789abcdefghijklmnopqrstuv]
143  * ptc == /dev/pty[pqrsPQRS][0123456789abcdefghijklmnopqrstuv]
144  *
145  * XXX: define and add mapping of upper minor bits to allow more
146  *      than 256 ptys.
147  */
148 static void
149 ptyinit(n)
150 	int n;
151 {
152 	dev_t devs, devc;
153 	char *names = "pqrsPQRS";
154 	struct pt_ioctl *pt;
155 
156 	/* For now we only map the lower 8 bits of the minor */
157 	if (n & ~0xff)
158 		return;
159 
160 	pt = malloc(sizeof(*pt), M_PTY, M_WAITOK);
161 	bzero(pt, sizeof(*pt));
162 	pt->devs = devs = make_dev(&pts_cdevsw, n,
163 	    0, 0, 0666, "tty%c%r", names[n / 32], n % 32);
164 	pt->devc = devc = make_dev(&ptc_cdevsw, n,
165 	    0, 0, 0666, "pty%c%r", names[n / 32], n % 32);
166 
167 	devs->si_drv1 = devc->si_drv1 = pt;
168 	devs->si_tty = devc->si_tty = &pt->pt_tty;
169 	pt->pt_tty.t_dev = devs;
170 	ttyregister(&pt->pt_tty);
171 }
172 
173 /*ARGSUSED*/
174 static	int
175 ptsopen(dev_t dev, int flag, int devtype, struct thread *td)
176 {
177 	struct tty *tp;
178 	int error;
179 	int minr;
180 #if 0
181 	dev_t nextdev;
182 #endif
183 	struct pt_ioctl *pti;
184 	struct proc *p;
185 
186 	p = td->td_proc;
187 	KKASSERT(p != NULL);
188 
189 	minr = lminor(dev);
190 #if 0
191 	/*
192 	 * REMOVED gross hack for devfs.  also note that makedev()
193 	 * no longer exists in this form and reference counting makes
194 	 * this a problem if we don't clean it out later.
195 	 */
196 	if (minr < 255) {
197 		nextdev = make_sub_dev(dev, minr + 1);
198 		if (!nextdev->si_drv1) {
199 			ptyinit(minr + 1);
200 		}
201 	}
202 #endif
203 	if (!dev->si_drv1)
204 		ptyinit(minor(dev));
205 	if (!dev->si_drv1)
206 		return(ENXIO);
207 	pti = dev->si_drv1;
208 	tp = dev->si_tty;
209 	if ((tp->t_state & TS_ISOPEN) == 0) {
210 		ttychars(tp);		/* Set up default chars */
211 		tp->t_iflag = TTYDEF_IFLAG;
212 		tp->t_oflag = TTYDEF_OFLAG;
213 		tp->t_lflag = TTYDEF_LFLAG;
214 		tp->t_cflag = TTYDEF_CFLAG;
215 		tp->t_ispeed = tp->t_ospeed = TTYDEF_SPEED;
216 	} else if (tp->t_state & TS_XCLUDE && suser(td)) {
217 		return (EBUSY);
218 	} else if (pti->pt_prison != p->p_ucred->cr_prison) {
219 		return (EBUSY);
220 	}
221 	if (tp->t_oproc)			/* Ctrlr still around. */
222 		(void)(*linesw[tp->t_line].l_modem)(tp, 1);
223 	while ((tp->t_state & TS_CARR_ON) == 0) {
224 		if (flag&FNONBLOCK)
225 			break;
226 		error = ttysleep(tp, TSA_CARR_ON(tp), PCATCH, "ptsopn", 0);
227 		if (error)
228 			return (error);
229 	}
230 	error = (*linesw[tp->t_line].l_open)(dev, tp);
231 	if (error == 0)
232 		ptcwakeup(tp, FREAD|FWRITE);
233 	return (error);
234 }
235 
236 static	int
237 ptsclose(dev, flag, mode, td)
238 	dev_t dev;
239 	int flag, mode;
240 	struct thread *td;
241 {
242 	struct tty *tp;
243 	int err;
244 
245 	tp = dev->si_tty;
246 	err = (*linesw[tp->t_line].l_close)(tp, flag);
247 	ptsstop(tp, FREAD|FWRITE);
248 	(void) ttyclose(tp);
249 	return (err);
250 }
251 
252 static	int
253 ptsread(dev, uio, flag)
254 	dev_t dev;
255 	struct uio *uio;
256 	int flag;
257 {
258 	struct proc *p = curproc;
259 	struct tty *tp = dev->si_tty;
260 	struct pt_ioctl *pti = dev->si_drv1;
261 	int error = 0;
262 
263 again:
264 	if (pti->pt_flags & PF_REMOTE) {
265 		while (isbackground(p, tp)) {
266 			if (SIGISMEMBER(p->p_sigignore, SIGTTIN) ||
267 			    SIGISMEMBER(p->p_sigmask, SIGTTIN) ||
268 			    p->p_pgrp->pg_jobc == 0 || p->p_flag & P_PPWAIT)
269 				return (EIO);
270 			pgsignal(p->p_pgrp, SIGTTIN, 1);
271 			error = ttysleep(tp, &lbolt, PCATCH, "ptsbg", 0);
272 			if (error)
273 				return (error);
274 		}
275 		if (tp->t_canq.c_cc == 0) {
276 			if (flag & IO_NDELAY)
277 				return (EWOULDBLOCK);
278 			error = ttysleep(tp, TSA_PTS_READ(tp), PCATCH,
279 					 "ptsin", 0);
280 			if (error)
281 				return (error);
282 			goto again;
283 		}
284 		while (tp->t_canq.c_cc > 1 && uio->uio_resid > 0)
285 			if (ureadc(getc(&tp->t_canq), uio) < 0) {
286 				error = EFAULT;
287 				break;
288 			}
289 		if (tp->t_canq.c_cc == 1)
290 			(void) getc(&tp->t_canq);
291 		if (tp->t_canq.c_cc)
292 			return (error);
293 	} else
294 		if (tp->t_oproc)
295 			error = (*linesw[tp->t_line].l_read)(tp, uio, flag);
296 	ptcwakeup(tp, FWRITE);
297 	return (error);
298 }
299 
300 /*
301  * Write to pseudo-tty.
302  * Wakeups of controlling tty will happen
303  * indirectly, when tty driver calls ptsstart.
304  */
305 static	int
306 ptswrite(dev, uio, flag)
307 	dev_t dev;
308 	struct uio *uio;
309 	int flag;
310 {
311 	struct tty *tp;
312 
313 	tp = dev->si_tty;
314 	if (tp->t_oproc == 0)
315 		return (EIO);
316 	return ((*linesw[tp->t_line].l_write)(tp, uio, flag));
317 }
318 
319 /*
320  * Start output on pseudo-tty.
321  * Wake up process selecting or sleeping for input from controlling tty.
322  */
323 static void
324 ptsstart(tp)
325 	struct tty *tp;
326 {
327 	struct pt_ioctl *pti = tp->t_dev->si_drv1;
328 
329 	if (tp->t_state & TS_TTSTOP)
330 		return;
331 	if (pti->pt_flags & PF_STOPPED) {
332 		pti->pt_flags &= ~PF_STOPPED;
333 		pti->pt_send = TIOCPKT_START;
334 	}
335 	ptcwakeup(tp, FREAD);
336 }
337 
338 static void
339 ptcwakeup(tp, flag)
340 	struct tty *tp;
341 	int flag;
342 {
343 	struct pt_ioctl *pti = tp->t_dev->si_drv1;
344 
345 	if (flag & FREAD) {
346 		selwakeup(&pti->pt_selr);
347 		wakeup(TSA_PTC_READ(tp));
348 	}
349 	if (flag & FWRITE) {
350 		selwakeup(&pti->pt_selw);
351 		wakeup(TSA_PTC_WRITE(tp));
352 	}
353 }
354 
355 static	int
356 ptcopen(dev, flag, devtype, td)
357 	dev_t dev;
358 	int flag, devtype;
359 	struct thread *td;
360 {
361 	struct tty *tp;
362 	struct pt_ioctl *pti;
363 
364 	if (!dev->si_drv1)
365 		ptyinit(minor(dev));
366 	if (!dev->si_drv1)
367 		return(ENXIO);
368 	tp = dev->si_tty;
369 	if (tp->t_oproc)
370 		return (EIO);
371 	KKASSERT(td->td_proc != NULL);
372 	tp->t_oproc = ptsstart;
373 	tp->t_stop = ptsstop;
374 	(void)(*linesw[tp->t_line].l_modem)(tp, 1);
375 	tp->t_lflag &= ~EXTPROC;
376 	pti = dev->si_drv1;
377 	pti->pt_prison = td->td_proc->p_ucred->cr_prison;
378 	pti->pt_flags = 0;
379 	pti->pt_send = 0;
380 	pti->pt_ucntl = 0;
381 	return (0);
382 }
383 
384 static	int
385 ptcclose(dev, flags, fmt, td)
386 	dev_t dev;
387 	int flags;
388 	int fmt;
389 	struct thread *td;
390 {
391 	struct tty *tp;
392 
393 	tp = dev->si_tty;
394 	(void)(*linesw[tp->t_line].l_modem)(tp, 0);
395 
396 	/*
397 	 * XXX MDMBUF makes no sense for ptys but would inhibit the above
398 	 * l_modem().  CLOCAL makes sense but isn't supported.   Special
399 	 * l_modem()s that ignore carrier drop make no sense for ptys but
400 	 * may be in use because other parts of the line discipline make
401 	 * sense for ptys.  Recover by doing everything that a normal
402 	 * ttymodem() would have done except for sending a SIGHUP.
403 	 */
404 	if (tp->t_state & TS_ISOPEN) {
405 		tp->t_state &= ~(TS_CARR_ON | TS_CONNECTED);
406 		tp->t_state |= TS_ZOMBIE;
407 		ttyflush(tp, FREAD | FWRITE);
408 	}
409 
410 	tp->t_oproc = 0;		/* mark closed */
411 	return (0);
412 }
413 
414 static	int
415 ptcread(dev, uio, flag)
416 	dev_t dev;
417 	struct uio *uio;
418 	int flag;
419 {
420 	struct tty *tp = dev->si_tty;
421 	struct pt_ioctl *pti = dev->si_drv1;
422 	char buf[BUFSIZ];
423 	int error = 0, cc;
424 
425 	/*
426 	 * We want to block until the slave
427 	 * is open, and there's something to read;
428 	 * but if we lost the slave or we're NBIO,
429 	 * then return the appropriate error instead.
430 	 */
431 	for (;;) {
432 		if (tp->t_state&TS_ISOPEN) {
433 			if (pti->pt_flags&PF_PKT && pti->pt_send) {
434 				error = ureadc((int)pti->pt_send, uio);
435 				if (error)
436 					return (error);
437 				if (pti->pt_send & TIOCPKT_IOCTL) {
438 					cc = min(uio->uio_resid,
439 						sizeof(tp->t_termios));
440 					uiomove((caddr_t)&tp->t_termios, cc,
441 						uio);
442 				}
443 				pti->pt_send = 0;
444 				return (0);
445 			}
446 			if (pti->pt_flags&PF_UCNTL && pti->pt_ucntl) {
447 				error = ureadc((int)pti->pt_ucntl, uio);
448 				if (error)
449 					return (error);
450 				pti->pt_ucntl = 0;
451 				return (0);
452 			}
453 			if (tp->t_outq.c_cc && (tp->t_state&TS_TTSTOP) == 0)
454 				break;
455 		}
456 		if ((tp->t_state & TS_CONNECTED) == 0)
457 			return (0);	/* EOF */
458 		if (flag & IO_NDELAY)
459 			return (EWOULDBLOCK);
460 		error = tsleep(TSA_PTC_READ(tp), PCATCH, "ptcin", 0);
461 		if (error)
462 			return (error);
463 	}
464 	if (pti->pt_flags & (PF_PKT|PF_UCNTL))
465 		error = ureadc(0, uio);
466 	while (uio->uio_resid > 0 && error == 0) {
467 		cc = q_to_b(&tp->t_outq, buf, min(uio->uio_resid, BUFSIZ));
468 		if (cc <= 0)
469 			break;
470 		error = uiomove(buf, cc, uio);
471 	}
472 	ttwwakeup(tp);
473 	return (error);
474 }
475 
476 static	void
477 ptsstop(tp, flush)
478 	struct tty *tp;
479 	int flush;
480 {
481 	struct pt_ioctl *pti = tp->t_dev->si_drv1;
482 	int flag;
483 
484 	/* note: FLUSHREAD and FLUSHWRITE already ok */
485 	if (flush == 0) {
486 		flush = TIOCPKT_STOP;
487 		pti->pt_flags |= PF_STOPPED;
488 	} else
489 		pti->pt_flags &= ~PF_STOPPED;
490 	pti->pt_send |= flush;
491 	/* change of perspective */
492 	flag = 0;
493 	if (flush & FREAD)
494 		flag |= FWRITE;
495 	if (flush & FWRITE)
496 		flag |= FREAD;
497 	ptcwakeup(tp, flag);
498 }
499 
500 static	int
501 ptcpoll(dev, events, td)
502 	dev_t dev;
503 	int events;
504 	struct thread *td;
505 {
506 	struct tty *tp = dev->si_tty;
507 	struct pt_ioctl *pti = dev->si_drv1;
508 	int revents = 0;
509 	int s;
510 
511 	if ((tp->t_state & TS_CONNECTED) == 0)
512 		return (seltrue(dev, events, td) | POLLHUP);
513 
514 	/*
515 	 * Need to block timeouts (ttrstart).
516 	 */
517 	s = spltty();
518 
519 	if (events & (POLLIN | POLLRDNORM))
520 		if ((tp->t_state & TS_ISOPEN) &&
521 		    ((tp->t_outq.c_cc && (tp->t_state & TS_TTSTOP) == 0) ||
522 		     ((pti->pt_flags & PF_PKT) && pti->pt_send) ||
523 		     ((pti->pt_flags & PF_UCNTL) && pti->pt_ucntl)))
524 			revents |= events & (POLLIN | POLLRDNORM);
525 
526 	if (events & (POLLOUT | POLLWRNORM))
527 		if (tp->t_state & TS_ISOPEN &&
528 		    ((pti->pt_flags & PF_REMOTE) ?
529 		     (tp->t_canq.c_cc == 0) :
530 		     ((tp->t_rawq.c_cc + tp->t_canq.c_cc < TTYHOG - 2) ||
531 		      (tp->t_canq.c_cc == 0 && (tp->t_lflag & ICANON)))))
532 			revents |= events & (POLLOUT | POLLWRNORM);
533 
534 	if (events & POLLHUP)
535 		if ((tp->t_state & TS_CARR_ON) == 0)
536 			revents |= POLLHUP;
537 
538 	if (revents == 0) {
539 		if (events & (POLLIN | POLLRDNORM))
540 			selrecord(td, &pti->pt_selr);
541 
542 		if (events & (POLLOUT | POLLWRNORM))
543 			selrecord(td, &pti->pt_selw);
544 	}
545 	splx(s);
546 
547 	return (revents);
548 }
549 
550 static	int
551 ptcwrite(dev, uio, flag)
552 	dev_t dev;
553 	struct uio *uio;
554 	int flag;
555 {
556 	struct tty *tp = dev->si_tty;
557 	u_char *cp = 0;
558 	int cc = 0;
559 	u_char locbuf[BUFSIZ];
560 	int cnt = 0;
561 	struct pt_ioctl *pti = dev->si_drv1;
562 	int error = 0;
563 
564 again:
565 	if ((tp->t_state&TS_ISOPEN) == 0)
566 		goto block;
567 	if (pti->pt_flags & PF_REMOTE) {
568 		if (tp->t_canq.c_cc)
569 			goto block;
570 		while ((uio->uio_resid > 0 || cc > 0) &&
571 		       tp->t_canq.c_cc < TTYHOG - 1) {
572 			if (cc == 0) {
573 				cc = min(uio->uio_resid, BUFSIZ);
574 				cc = min(cc, TTYHOG - 1 - tp->t_canq.c_cc);
575 				cp = locbuf;
576 				error = uiomove((caddr_t)cp, cc, uio);
577 				if (error)
578 					return (error);
579 				/* check again for safety */
580 				if ((tp->t_state & TS_ISOPEN) == 0) {
581 					/* adjust as usual */
582 					uio->uio_resid += cc;
583 					return (EIO);
584 				}
585 			}
586 			if (cc > 0) {
587 				cc = b_to_q((char *)cp, cc, &tp->t_canq);
588 				/*
589 				 * XXX we don't guarantee that the canq size
590 				 * is >= TTYHOG, so the above b_to_q() may
591 				 * leave some bytes uncopied.  However, space
592 				 * is guaranteed for the null terminator if
593 				 * we don't fail here since (TTYHOG - 1) is
594 				 * not a multiple of CBSIZE.
595 				 */
596 				if (cc > 0)
597 					break;
598 			}
599 		}
600 		/* adjust for data copied in but not written */
601 		uio->uio_resid += cc;
602 		(void) putc(0, &tp->t_canq);
603 		ttwakeup(tp);
604 		wakeup(TSA_PTS_READ(tp));
605 		return (0);
606 	}
607 	while (uio->uio_resid > 0 || cc > 0) {
608 		if (cc == 0) {
609 			cc = min(uio->uio_resid, BUFSIZ);
610 			cp = locbuf;
611 			error = uiomove((caddr_t)cp, cc, uio);
612 			if (error)
613 				return (error);
614 			/* check again for safety */
615 			if ((tp->t_state & TS_ISOPEN) == 0) {
616 				/* adjust for data copied in but not written */
617 				uio->uio_resid += cc;
618 				return (EIO);
619 			}
620 		}
621 		while (cc > 0) {
622 			if ((tp->t_rawq.c_cc + tp->t_canq.c_cc) >= TTYHOG - 2 &&
623 			   (tp->t_canq.c_cc > 0 || !(tp->t_lflag&ICANON))) {
624 				wakeup(TSA_HUP_OR_INPUT(tp));
625 				goto block;
626 			}
627 			(*linesw[tp->t_line].l_rint)(*cp++, tp);
628 			cnt++;
629 			cc--;
630 		}
631 		cc = 0;
632 	}
633 	return (0);
634 block:
635 	/*
636 	 * Come here to wait for slave to open, for space
637 	 * in outq, or space in rawq, or an empty canq.
638 	 */
639 	if ((tp->t_state & TS_CONNECTED) == 0) {
640 		/* adjust for data copied in but not written */
641 		uio->uio_resid += cc;
642 		return (EIO);
643 	}
644 	if (flag & IO_NDELAY) {
645 		/* adjust for data copied in but not written */
646 		uio->uio_resid += cc;
647 		if (cnt == 0)
648 			return (EWOULDBLOCK);
649 		return (0);
650 	}
651 	error = tsleep(TSA_PTC_WRITE(tp), PCATCH, "ptcout", 0);
652 	if (error) {
653 		/* adjust for data copied in but not written */
654 		uio->uio_resid += cc;
655 		return (error);
656 	}
657 	goto again;
658 }
659 
660 /*ARGSUSED*/
661 static	int
662 ptyioctl(dev, cmd, data, flag, td)
663 	dev_t dev;
664 	u_long cmd;
665 	caddr_t data;
666 	int flag;
667 	struct thread *td;
668 {
669 	struct tty *tp = dev->si_tty;
670 	struct pt_ioctl *pti = dev->si_drv1;
671 	u_char *cc = tp->t_cc;
672 	int stop, error;
673 
674 	if (dev_dflags(dev) & D_MASTER) {
675 		switch (cmd) {
676 
677 		case TIOCGPGRP:
678 			/*
679 			 * We avoid calling ttioctl on the controller since,
680 			 * in that case, tp must be the controlling terminal.
681 			 */
682 			*(int *)data = tp->t_pgrp ? tp->t_pgrp->pg_id : 0;
683 			return (0);
684 
685 		case TIOCPKT:
686 			if (*(int *)data) {
687 				if (pti->pt_flags & PF_UCNTL)
688 					return (EINVAL);
689 				pti->pt_flags |= PF_PKT;
690 			} else
691 				pti->pt_flags &= ~PF_PKT;
692 			return (0);
693 
694 		case TIOCUCNTL:
695 			if (*(int *)data) {
696 				if (pti->pt_flags & PF_PKT)
697 					return (EINVAL);
698 				pti->pt_flags |= PF_UCNTL;
699 			} else
700 				pti->pt_flags &= ~PF_UCNTL;
701 			return (0);
702 
703 		case TIOCREMOTE:
704 			if (*(int *)data)
705 				pti->pt_flags |= PF_REMOTE;
706 			else
707 				pti->pt_flags &= ~PF_REMOTE;
708 			ttyflush(tp, FREAD|FWRITE);
709 			return (0);
710 		}
711 
712 		/*
713 		 * The rest of the ioctls shouldn't be called until
714 		 * the slave is open.
715 		 */
716 		if ((tp->t_state & TS_ISOPEN) == 0)
717 			return (EAGAIN);
718 
719 		switch (cmd) {
720 #ifdef COMPAT_43
721 		case TIOCSETP:
722 		case TIOCSETN:
723 #endif
724 		case TIOCSETD:
725 		case TIOCSETA:
726 		case TIOCSETAW:
727 		case TIOCSETAF:
728 			/*
729 			 * IF CONTROLLER STTY THEN MUST FLUSH TO PREVENT A HANG.
730 			 * ttywflush(tp) will hang if there are characters in
731 			 * the outq.
732 			 */
733 			ndflush(&tp->t_outq, tp->t_outq.c_cc);
734 			break;
735 
736 		case TIOCSIG:
737 			if (*(unsigned int *)data >= NSIG ||
738 			    *(unsigned int *)data == 0)
739 				return(EINVAL);
740 			if ((tp->t_lflag&NOFLSH) == 0)
741 				ttyflush(tp, FREAD|FWRITE);
742 			pgsignal(tp->t_pgrp, *(unsigned int *)data, 1);
743 			if ((*(unsigned int *)data == SIGINFO) &&
744 			    ((tp->t_lflag&NOKERNINFO) == 0))
745 				ttyinfo(tp);
746 			return(0);
747 		}
748 	}
749 	if (cmd == TIOCEXT) {
750 		/*
751 		 * When the EXTPROC bit is being toggled, we need
752 		 * to send an TIOCPKT_IOCTL if the packet driver
753 		 * is turned on.
754 		 */
755 		if (*(int *)data) {
756 			if (pti->pt_flags & PF_PKT) {
757 				pti->pt_send |= TIOCPKT_IOCTL;
758 				ptcwakeup(tp, FREAD);
759 			}
760 			tp->t_lflag |= EXTPROC;
761 		} else {
762 			if ((tp->t_lflag & EXTPROC) &&
763 			    (pti->pt_flags & PF_PKT)) {
764 				pti->pt_send |= TIOCPKT_IOCTL;
765 				ptcwakeup(tp, FREAD);
766 			}
767 			tp->t_lflag &= ~EXTPROC;
768 		}
769 		return(0);
770 	}
771 	error = (*linesw[tp->t_line].l_ioctl)(tp, cmd, data, flag, td);
772 	if (error == ENOIOCTL)
773 		 error = ttioctl(tp, cmd, data, flag);
774 	if (error == ENOIOCTL) {
775 		if (pti->pt_flags & PF_UCNTL &&
776 		    (cmd & ~0xff) == UIOCCMD(0)) {
777 			if (cmd & 0xff) {
778 				pti->pt_ucntl = (u_char)cmd;
779 				ptcwakeup(tp, FREAD);
780 			}
781 			return (0);
782 		}
783 		error = ENOTTY;
784 	}
785 	/*
786 	 * If external processing and packet mode send ioctl packet.
787 	 */
788 	if ((tp->t_lflag&EXTPROC) && (pti->pt_flags & PF_PKT)) {
789 		switch(cmd) {
790 		case TIOCSETA:
791 		case TIOCSETAW:
792 		case TIOCSETAF:
793 #ifdef COMPAT_43
794 		case TIOCSETP:
795 		case TIOCSETN:
796 #endif
797 #if defined(COMPAT_43) || defined(COMPAT_SUNOS)
798 		case TIOCSETC:
799 		case TIOCSLTC:
800 		case TIOCLBIS:
801 		case TIOCLBIC:
802 		case TIOCLSET:
803 #endif
804 			pti->pt_send |= TIOCPKT_IOCTL;
805 			ptcwakeup(tp, FREAD);
806 		default:
807 			break;
808 		}
809 	}
810 	stop = (tp->t_iflag & IXON) && CCEQ(cc[VSTOP], CTRL('s'))
811 		&& CCEQ(cc[VSTART], CTRL('q'));
812 	if (pti->pt_flags & PF_NOSTOP) {
813 		if (stop) {
814 			pti->pt_send &= ~TIOCPKT_NOSTOP;
815 			pti->pt_send |= TIOCPKT_DOSTOP;
816 			pti->pt_flags &= ~PF_NOSTOP;
817 			ptcwakeup(tp, FREAD);
818 		}
819 	} else {
820 		if (!stop) {
821 			pti->pt_send &= ~TIOCPKT_DOSTOP;
822 			pti->pt_send |= TIOCPKT_NOSTOP;
823 			pti->pt_flags |= PF_NOSTOP;
824 			ptcwakeup(tp, FREAD);
825 		}
826 	}
827 	return (error);
828 }
829 
830 
831 static void ptc_drvinit (void *unused);
832 
833 static void
834 ptc_drvinit(unused)
835 	void *unused;
836 {
837 	cdevsw_add(&pts_cdevsw, 0, 0);
838 	cdevsw_add(&ptc_cdevsw, 0, 0);
839 	/* XXX: Gross hack for DEVFS */
840 	/* XXX: DEVFS is no more, should this be removed? */
841 	ptyinit(0);
842 }
843 
844 SYSINIT(ptcdev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR_C,ptc_drvinit,NULL)
845