xref: /dragonfly/sys/kern/tty_pty.c (revision cdecd76a)
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 1.8 2003/07/26 19:42:11 rob Exp $
36  */
37 
38 /*
39  * Pseudo-teletype Driver
40  * (Actually two drivers, requiring two entries in 'cdevsw')
41  */
42 #include "pty.h"		/* XXX */
43 #include "opt_compat.h"
44 #include <sys/param.h>
45 #include <sys/systm.h>
46 #if defined(COMPAT_43) || defined(COMPAT_SUNOS)
47 #include <sys/ioctl_compat.h>
48 #endif
49 #include <sys/proc.h>
50 #include <sys/tty.h>
51 #include <sys/conf.h>
52 #include <sys/fcntl.h>
53 #include <sys/poll.h>
54 #include <sys/kernel.h>
55 #include <sys/vnode.h>
56 #include <sys/signalvar.h>
57 #include <sys/malloc.h>
58 #include <sys/device.h>
59 
60 MALLOC_DEFINE(M_PTY, "ptys", "pty data structures");
61 
62 static void ptsstart __P((struct tty *tp));
63 static void ptsstop __P((struct tty *tp, int rw));
64 static void ptcwakeup __P((struct tty *tp, int flag));
65 static void ptyinit __P((int n));
66 
67 static	d_open_t	ptsopen;
68 static	d_close_t	ptsclose;
69 static	d_read_t	ptsread;
70 static	d_write_t	ptswrite;
71 static	d_ioctl_t	ptyioctl;
72 static	d_open_t	ptcopen;
73 static	d_close_t	ptcclose;
74 static	d_read_t	ptcread;
75 static	d_write_t	ptcwrite;
76 static	d_poll_t	ptcpoll;
77 
78 #define	CDEV_MAJOR_S	5
79 static struct cdevsw pts_cdevsw = {
80 	/* name */	"pts",
81 	/* maj */	CDEV_MAJOR_S,
82 	/* flags */	D_TTY | D_KQFILTER,
83 	/* port */	NULL,
84 	/* autoq */	0,
85 
86 	/* open */	ptsopen,
87 	/* close */	ptsclose,
88 	/* read */	ptsread,
89 	/* write */	ptswrite,
90 	/* ioctl */	ptyioctl,
91 	/* poll */	ttypoll,
92 	/* mmap */	nommap,
93 	/* strategy */	nostrategy,
94 	/* dump */	nodump,
95 	/* psize */	nopsize,
96 	/* kqfilter */	ttykqfilter
97 };
98 
99 #define	CDEV_MAJOR_C	6
100 static struct cdevsw ptc_cdevsw = {
101 	/* name */	"ptc",
102 	/* maj */	CDEV_MAJOR_C,
103 	/* flags */	D_TTY | D_KQFILTER | D_MASTER,
104 	/* port */	NULL,
105 	/* autoq */	0,
106 
107 	/* open */	ptcopen,
108 	/* close */	ptcclose,
109 	/* read */	ptcread,
110 	/* write */	ptcwrite,
111 	/* ioctl */	ptyioctl,
112 	/* poll */	ptcpoll,
113 	/* mmap */	nommap,
114 	/* strategy */	nostrategy,
115 	/* dump */	nodump,
116 	/* psize */	nopsize,
117 	/* kqfilter */	ttykqfilter
118 };
119 
120 #define BUFSIZ 100		/* Chunk size iomoved to/from user */
121 
122 struct	pt_ioctl {
123 	int	pt_flags;
124 	struct	selinfo pt_selr, pt_selw;
125 	u_char	pt_send;
126 	u_char	pt_ucntl;
127 	struct tty pt_tty;
128 	dev_t	devs, devc;
129 	struct	prison *pt_prison;
130 };
131 
132 #define	PF_PKT		0x08		/* packet mode */
133 #define	PF_STOPPED	0x10		/* user told stopped */
134 #define	PF_REMOTE	0x20		/* remote and flow controlled input */
135 #define	PF_NOSTOP	0x40
136 #define PF_UCNTL	0x80		/* user control mode */
137 
138 /*
139  * This function creates and initializes a pts/ptc pair
140  *
141  * pts == /dev/tty[pqrsPQRS][0123456789abcdefghijklmnopqrstuv]
142  * ptc == /dev/pty[pqrsPQRS][0123456789abcdefghijklmnopqrstuv]
143  *
144  * XXX: define and add mapping of upper minor bits to allow more
145  *      than 256 ptys.
146  */
147 static void
148 ptyinit(n)
149 	int n;
150 {
151 	dev_t devs, devc;
152 	char *names = "pqrsPQRS";
153 	struct pt_ioctl *pt;
154 
155 	/* For now we only map the lower 8 bits of the minor */
156 	if (n & ~0xff)
157 		return;
158 
159 	pt = malloc(sizeof(*pt), M_PTY, M_WAITOK);
160 	bzero(pt, sizeof(*pt));
161 	pt->devs = devs = make_dev(&pts_cdevsw, n,
162 	    0, 0, 0666, "tty%c%r", names[n / 32], n % 32);
163 	pt->devc = devc = make_dev(&ptc_cdevsw, n,
164 	    0, 0, 0666, "pty%c%r", names[n / 32], n % 32);
165 
166 	devs->si_drv1 = devc->si_drv1 = pt;
167 	devs->si_tty = devc->si_tty = &pt->pt_tty;
168 	pt->pt_tty.t_dev = devs;
169 	ttyregister(&pt->pt_tty);
170 }
171 
172 /*ARGSUSED*/
173 static	int
174 ptsopen(dev_t dev, int flag, int devtype, struct thread *td)
175 {
176 	struct tty *tp;
177 	int error;
178 	int minr;
179 	dev_t nextdev;
180 	struct pt_ioctl *pti;
181 	struct proc *p;
182 
183 	p = td->td_proc;
184 	KKASSERT(p != NULL);
185 
186 	/*
187 	 * XXX: Gross hack for DEVFS:
188 	 * XXX: DEVFS is no more, should this be removed?
189 	 * If we openned this device, ensure we have the
190 	 * next one too, so people can open it.
191 	 */
192 	minr = lminor(dev);
193 	if (minr < 255) {
194 		nextdev = makedev(major(dev), minr + 1);
195 		if (!nextdev->si_drv1) {
196 			ptyinit(minr + 1);
197 		}
198 	}
199 	if (!dev->si_drv1)
200 		ptyinit(minor(dev));
201 	if (!dev->si_drv1)
202 		return(ENXIO);
203 	pti = dev->si_drv1;
204 	tp = dev->si_tty;
205 	if ((tp->t_state & TS_ISOPEN) == 0) {
206 		ttychars(tp);		/* Set up default chars */
207 		tp->t_iflag = TTYDEF_IFLAG;
208 		tp->t_oflag = TTYDEF_OFLAG;
209 		tp->t_lflag = TTYDEF_LFLAG;
210 		tp->t_cflag = TTYDEF_CFLAG;
211 		tp->t_ispeed = tp->t_ospeed = TTYDEF_SPEED;
212 	} else if (tp->t_state & TS_XCLUDE && suser(td)) {
213 		return (EBUSY);
214 	} else if (pti->pt_prison != p->p_ucred->cr_prison) {
215 		return (EBUSY);
216 	}
217 	if (tp->t_oproc)			/* Ctrlr still around. */
218 		(void)(*linesw[tp->t_line].l_modem)(tp, 1);
219 	while ((tp->t_state & TS_CARR_ON) == 0) {
220 		if (flag&FNONBLOCK)
221 			break;
222 		error = ttysleep(tp, TSA_CARR_ON(tp), PCATCH, "ptsopn", 0);
223 		if (error)
224 			return (error);
225 	}
226 	error = (*linesw[tp->t_line].l_open)(dev, tp);
227 	if (error == 0)
228 		ptcwakeup(tp, FREAD|FWRITE);
229 	return (error);
230 }
231 
232 static	int
233 ptsclose(dev, flag, mode, td)
234 	dev_t dev;
235 	int flag, mode;
236 	struct thread *td;
237 {
238 	struct tty *tp;
239 	int err;
240 
241 	tp = dev->si_tty;
242 	err = (*linesw[tp->t_line].l_close)(tp, flag);
243 	ptsstop(tp, FREAD|FWRITE);
244 	(void) ttyclose(tp);
245 	return (err);
246 }
247 
248 static	int
249 ptsread(dev, uio, flag)
250 	dev_t dev;
251 	struct uio *uio;
252 	int flag;
253 {
254 	struct proc *p = curproc;
255 	struct tty *tp = dev->si_tty;
256 	struct pt_ioctl *pti = dev->si_drv1;
257 	int error = 0;
258 
259 again:
260 	if (pti->pt_flags & PF_REMOTE) {
261 		while (isbackground(p, tp)) {
262 			if (SIGISMEMBER(p->p_sigignore, SIGTTIN) ||
263 			    SIGISMEMBER(p->p_sigmask, SIGTTIN) ||
264 			    p->p_pgrp->pg_jobc == 0 || p->p_flag & P_PPWAIT)
265 				return (EIO);
266 			pgsignal(p->p_pgrp, SIGTTIN, 1);
267 			error = ttysleep(tp, &lbolt, PCATCH, "ptsbg", 0);
268 			if (error)
269 				return (error);
270 		}
271 		if (tp->t_canq.c_cc == 0) {
272 			if (flag & IO_NDELAY)
273 				return (EWOULDBLOCK);
274 			error = ttysleep(tp, TSA_PTS_READ(tp), PCATCH,
275 					 "ptsin", 0);
276 			if (error)
277 				return (error);
278 			goto again;
279 		}
280 		while (tp->t_canq.c_cc > 1 && uio->uio_resid > 0)
281 			if (ureadc(getc(&tp->t_canq), uio) < 0) {
282 				error = EFAULT;
283 				break;
284 			}
285 		if (tp->t_canq.c_cc == 1)
286 			(void) getc(&tp->t_canq);
287 		if (tp->t_canq.c_cc)
288 			return (error);
289 	} else
290 		if (tp->t_oproc)
291 			error = (*linesw[tp->t_line].l_read)(tp, uio, flag);
292 	ptcwakeup(tp, FWRITE);
293 	return (error);
294 }
295 
296 /*
297  * Write to pseudo-tty.
298  * Wakeups of controlling tty will happen
299  * indirectly, when tty driver calls ptsstart.
300  */
301 static	int
302 ptswrite(dev, uio, flag)
303 	dev_t dev;
304 	struct uio *uio;
305 	int flag;
306 {
307 	struct tty *tp;
308 
309 	tp = dev->si_tty;
310 	if (tp->t_oproc == 0)
311 		return (EIO);
312 	return ((*linesw[tp->t_line].l_write)(tp, uio, flag));
313 }
314 
315 /*
316  * Start output on pseudo-tty.
317  * Wake up process selecting or sleeping for input from controlling tty.
318  */
319 static void
320 ptsstart(tp)
321 	struct tty *tp;
322 {
323 	struct pt_ioctl *pti = tp->t_dev->si_drv1;
324 
325 	if (tp->t_state & TS_TTSTOP)
326 		return;
327 	if (pti->pt_flags & PF_STOPPED) {
328 		pti->pt_flags &= ~PF_STOPPED;
329 		pti->pt_send = TIOCPKT_START;
330 	}
331 	ptcwakeup(tp, FREAD);
332 }
333 
334 static void
335 ptcwakeup(tp, flag)
336 	struct tty *tp;
337 	int flag;
338 {
339 	struct pt_ioctl *pti = tp->t_dev->si_drv1;
340 
341 	if (flag & FREAD) {
342 		selwakeup(&pti->pt_selr);
343 		wakeup(TSA_PTC_READ(tp));
344 	}
345 	if (flag & FWRITE) {
346 		selwakeup(&pti->pt_selw);
347 		wakeup(TSA_PTC_WRITE(tp));
348 	}
349 }
350 
351 static	int
352 ptcopen(dev, flag, devtype, td)
353 	dev_t dev;
354 	int flag, devtype;
355 	struct thread *td;
356 {
357 	struct tty *tp;
358 	struct pt_ioctl *pti;
359 
360 	if (!dev->si_drv1)
361 		ptyinit(minor(dev));
362 	if (!dev->si_drv1)
363 		return(ENXIO);
364 	tp = dev->si_tty;
365 	if (tp->t_oproc)
366 		return (EIO);
367 	KKASSERT(td->td_proc != NULL);
368 	tp->t_oproc = ptsstart;
369 	tp->t_stop = ptsstop;
370 	(void)(*linesw[tp->t_line].l_modem)(tp, 1);
371 	tp->t_lflag &= ~EXTPROC;
372 	pti = dev->si_drv1;
373 	pti->pt_prison = td->td_proc->p_ucred->cr_prison;
374 	pti->pt_flags = 0;
375 	pti->pt_send = 0;
376 	pti->pt_ucntl = 0;
377 	return (0);
378 }
379 
380 static	int
381 ptcclose(dev, flags, fmt, td)
382 	dev_t dev;
383 	int flags;
384 	int fmt;
385 	struct thread *td;
386 {
387 	struct tty *tp;
388 
389 	tp = dev->si_tty;
390 	(void)(*linesw[tp->t_line].l_modem)(tp, 0);
391 
392 	/*
393 	 * XXX MDMBUF makes no sense for ptys but would inhibit the above
394 	 * l_modem().  CLOCAL makes sense but isn't supported.   Special
395 	 * l_modem()s that ignore carrier drop make no sense for ptys but
396 	 * may be in use because other parts of the line discipline make
397 	 * sense for ptys.  Recover by doing everything that a normal
398 	 * ttymodem() would have done except for sending a SIGHUP.
399 	 */
400 	if (tp->t_state & TS_ISOPEN) {
401 		tp->t_state &= ~(TS_CARR_ON | TS_CONNECTED);
402 		tp->t_state |= TS_ZOMBIE;
403 		ttyflush(tp, FREAD | FWRITE);
404 	}
405 
406 	tp->t_oproc = 0;		/* mark closed */
407 	return (0);
408 }
409 
410 static	int
411 ptcread(dev, uio, flag)
412 	dev_t dev;
413 	struct uio *uio;
414 	int flag;
415 {
416 	struct tty *tp = dev->si_tty;
417 	struct pt_ioctl *pti = dev->si_drv1;
418 	char buf[BUFSIZ];
419 	int error = 0, cc;
420 
421 	/*
422 	 * We want to block until the slave
423 	 * is open, and there's something to read;
424 	 * but if we lost the slave or we're NBIO,
425 	 * then return the appropriate error instead.
426 	 */
427 	for (;;) {
428 		if (tp->t_state&TS_ISOPEN) {
429 			if (pti->pt_flags&PF_PKT && pti->pt_send) {
430 				error = ureadc((int)pti->pt_send, uio);
431 				if (error)
432 					return (error);
433 				if (pti->pt_send & TIOCPKT_IOCTL) {
434 					cc = min(uio->uio_resid,
435 						sizeof(tp->t_termios));
436 					uiomove((caddr_t)&tp->t_termios, cc,
437 						uio);
438 				}
439 				pti->pt_send = 0;
440 				return (0);
441 			}
442 			if (pti->pt_flags&PF_UCNTL && pti->pt_ucntl) {
443 				error = ureadc((int)pti->pt_ucntl, uio);
444 				if (error)
445 					return (error);
446 				pti->pt_ucntl = 0;
447 				return (0);
448 			}
449 			if (tp->t_outq.c_cc && (tp->t_state&TS_TTSTOP) == 0)
450 				break;
451 		}
452 		if ((tp->t_state & TS_CONNECTED) == 0)
453 			return (0);	/* EOF */
454 		if (flag & IO_NDELAY)
455 			return (EWOULDBLOCK);
456 		error = tsleep(TSA_PTC_READ(tp), PCATCH, "ptcin", 0);
457 		if (error)
458 			return (error);
459 	}
460 	if (pti->pt_flags & (PF_PKT|PF_UCNTL))
461 		error = ureadc(0, uio);
462 	while (uio->uio_resid > 0 && error == 0) {
463 		cc = q_to_b(&tp->t_outq, buf, min(uio->uio_resid, BUFSIZ));
464 		if (cc <= 0)
465 			break;
466 		error = uiomove(buf, cc, uio);
467 	}
468 	ttwwakeup(tp);
469 	return (error);
470 }
471 
472 static	void
473 ptsstop(tp, flush)
474 	struct tty *tp;
475 	int flush;
476 {
477 	struct pt_ioctl *pti = tp->t_dev->si_drv1;
478 	int flag;
479 
480 	/* note: FLUSHREAD and FLUSHWRITE already ok */
481 	if (flush == 0) {
482 		flush = TIOCPKT_STOP;
483 		pti->pt_flags |= PF_STOPPED;
484 	} else
485 		pti->pt_flags &= ~PF_STOPPED;
486 	pti->pt_send |= flush;
487 	/* change of perspective */
488 	flag = 0;
489 	if (flush & FREAD)
490 		flag |= FWRITE;
491 	if (flush & FWRITE)
492 		flag |= FREAD;
493 	ptcwakeup(tp, flag);
494 }
495 
496 static	int
497 ptcpoll(dev, events, td)
498 	dev_t dev;
499 	int events;
500 	struct thread *td;
501 {
502 	struct tty *tp = dev->si_tty;
503 	struct pt_ioctl *pti = dev->si_drv1;
504 	int revents = 0;
505 	int s;
506 
507 	if ((tp->t_state & TS_CONNECTED) == 0)
508 		return (seltrue(dev, events, td) | POLLHUP);
509 
510 	/*
511 	 * Need to block timeouts (ttrstart).
512 	 */
513 	s = spltty();
514 
515 	if (events & (POLLIN | POLLRDNORM))
516 		if ((tp->t_state & TS_ISOPEN) &&
517 		    ((tp->t_outq.c_cc && (tp->t_state & TS_TTSTOP) == 0) ||
518 		     ((pti->pt_flags & PF_PKT) && pti->pt_send) ||
519 		     ((pti->pt_flags & PF_UCNTL) && pti->pt_ucntl)))
520 			revents |= events & (POLLIN | POLLRDNORM);
521 
522 	if (events & (POLLOUT | POLLWRNORM))
523 		if (tp->t_state & TS_ISOPEN &&
524 		    ((pti->pt_flags & PF_REMOTE) ?
525 		     (tp->t_canq.c_cc == 0) :
526 		     ((tp->t_rawq.c_cc + tp->t_canq.c_cc < TTYHOG - 2) ||
527 		      (tp->t_canq.c_cc == 0 && (tp->t_lflag & ICANON)))))
528 			revents |= events & (POLLOUT | POLLWRNORM);
529 
530 	if (events & POLLHUP)
531 		if ((tp->t_state & TS_CARR_ON) == 0)
532 			revents |= POLLHUP;
533 
534 	if (revents == 0) {
535 		if (events & (POLLIN | POLLRDNORM))
536 			selrecord(td, &pti->pt_selr);
537 
538 		if (events & (POLLOUT | POLLWRNORM))
539 			selrecord(td, &pti->pt_selw);
540 	}
541 	splx(s);
542 
543 	return (revents);
544 }
545 
546 static	int
547 ptcwrite(dev, uio, flag)
548 	dev_t dev;
549 	struct uio *uio;
550 	int flag;
551 {
552 	struct tty *tp = dev->si_tty;
553 	u_char *cp = 0;
554 	int cc = 0;
555 	u_char locbuf[BUFSIZ];
556 	int cnt = 0;
557 	struct pt_ioctl *pti = dev->si_drv1;
558 	int error = 0;
559 
560 again:
561 	if ((tp->t_state&TS_ISOPEN) == 0)
562 		goto block;
563 	if (pti->pt_flags & PF_REMOTE) {
564 		if (tp->t_canq.c_cc)
565 			goto block;
566 		while ((uio->uio_resid > 0 || cc > 0) &&
567 		       tp->t_canq.c_cc < TTYHOG - 1) {
568 			if (cc == 0) {
569 				cc = min(uio->uio_resid, BUFSIZ);
570 				cc = min(cc, TTYHOG - 1 - tp->t_canq.c_cc);
571 				cp = locbuf;
572 				error = uiomove((caddr_t)cp, cc, uio);
573 				if (error)
574 					return (error);
575 				/* check again for safety */
576 				if ((tp->t_state & TS_ISOPEN) == 0) {
577 					/* adjust as usual */
578 					uio->uio_resid += cc;
579 					return (EIO);
580 				}
581 			}
582 			if (cc > 0) {
583 				cc = b_to_q((char *)cp, cc, &tp->t_canq);
584 				/*
585 				 * XXX we don't guarantee that the canq size
586 				 * is >= TTYHOG, so the above b_to_q() may
587 				 * leave some bytes uncopied.  However, space
588 				 * is guaranteed for the null terminator if
589 				 * we don't fail here since (TTYHOG - 1) is
590 				 * not a multiple of CBSIZE.
591 				 */
592 				if (cc > 0)
593 					break;
594 			}
595 		}
596 		/* adjust for data copied in but not written */
597 		uio->uio_resid += cc;
598 		(void) putc(0, &tp->t_canq);
599 		ttwakeup(tp);
600 		wakeup(TSA_PTS_READ(tp));
601 		return (0);
602 	}
603 	while (uio->uio_resid > 0 || cc > 0) {
604 		if (cc == 0) {
605 			cc = min(uio->uio_resid, BUFSIZ);
606 			cp = locbuf;
607 			error = uiomove((caddr_t)cp, cc, uio);
608 			if (error)
609 				return (error);
610 			/* check again for safety */
611 			if ((tp->t_state & TS_ISOPEN) == 0) {
612 				/* adjust for data copied in but not written */
613 				uio->uio_resid += cc;
614 				return (EIO);
615 			}
616 		}
617 		while (cc > 0) {
618 			if ((tp->t_rawq.c_cc + tp->t_canq.c_cc) >= TTYHOG - 2 &&
619 			   (tp->t_canq.c_cc > 0 || !(tp->t_lflag&ICANON))) {
620 				wakeup(TSA_HUP_OR_INPUT(tp));
621 				goto block;
622 			}
623 			(*linesw[tp->t_line].l_rint)(*cp++, tp);
624 			cnt++;
625 			cc--;
626 		}
627 		cc = 0;
628 	}
629 	return (0);
630 block:
631 	/*
632 	 * Come here to wait for slave to open, for space
633 	 * in outq, or space in rawq, or an empty canq.
634 	 */
635 	if ((tp->t_state & TS_CONNECTED) == 0) {
636 		/* adjust for data copied in but not written */
637 		uio->uio_resid += cc;
638 		return (EIO);
639 	}
640 	if (flag & IO_NDELAY) {
641 		/* adjust for data copied in but not written */
642 		uio->uio_resid += cc;
643 		if (cnt == 0)
644 			return (EWOULDBLOCK);
645 		return (0);
646 	}
647 	error = tsleep(TSA_PTC_WRITE(tp), PCATCH, "ptcout", 0);
648 	if (error) {
649 		/* adjust for data copied in but not written */
650 		uio->uio_resid += cc;
651 		return (error);
652 	}
653 	goto again;
654 }
655 
656 /*ARGSUSED*/
657 static	int
658 ptyioctl(dev, cmd, data, flag, td)
659 	dev_t dev;
660 	u_long cmd;
661 	caddr_t data;
662 	int flag;
663 	struct thread *td;
664 {
665 	struct tty *tp = dev->si_tty;
666 	struct pt_ioctl *pti = dev->si_drv1;
667 	u_char *cc = tp->t_cc;
668 	int stop, error;
669 
670 	if (dev_dflags(dev) & D_MASTER) {
671 		switch (cmd) {
672 
673 		case TIOCGPGRP:
674 			/*
675 			 * We avoid calling ttioctl on the controller since,
676 			 * in that case, tp must be the controlling terminal.
677 			 */
678 			*(int *)data = tp->t_pgrp ? tp->t_pgrp->pg_id : 0;
679 			return (0);
680 
681 		case TIOCPKT:
682 			if (*(int *)data) {
683 				if (pti->pt_flags & PF_UCNTL)
684 					return (EINVAL);
685 				pti->pt_flags |= PF_PKT;
686 			} else
687 				pti->pt_flags &= ~PF_PKT;
688 			return (0);
689 
690 		case TIOCUCNTL:
691 			if (*(int *)data) {
692 				if (pti->pt_flags & PF_PKT)
693 					return (EINVAL);
694 				pti->pt_flags |= PF_UCNTL;
695 			} else
696 				pti->pt_flags &= ~PF_UCNTL;
697 			return (0);
698 
699 		case TIOCREMOTE:
700 			if (*(int *)data)
701 				pti->pt_flags |= PF_REMOTE;
702 			else
703 				pti->pt_flags &= ~PF_REMOTE;
704 			ttyflush(tp, FREAD|FWRITE);
705 			return (0);
706 		}
707 
708 		/*
709 		 * The rest of the ioctls shouldn't be called until
710 		 * the slave is open.
711 		 */
712 		if ((tp->t_state & TS_ISOPEN) == 0)
713 			return (EAGAIN);
714 
715 		switch (cmd) {
716 #ifdef COMPAT_43
717 		case TIOCSETP:
718 		case TIOCSETN:
719 #endif
720 		case TIOCSETD:
721 		case TIOCSETA:
722 		case TIOCSETAW:
723 		case TIOCSETAF:
724 			/*
725 			 * IF CONTROLLER STTY THEN MUST FLUSH TO PREVENT A HANG.
726 			 * ttywflush(tp) will hang if there are characters in
727 			 * the outq.
728 			 */
729 			ndflush(&tp->t_outq, tp->t_outq.c_cc);
730 			break;
731 
732 		case TIOCSIG:
733 			if (*(unsigned int *)data >= NSIG ||
734 			    *(unsigned int *)data == 0)
735 				return(EINVAL);
736 			if ((tp->t_lflag&NOFLSH) == 0)
737 				ttyflush(tp, FREAD|FWRITE);
738 			pgsignal(tp->t_pgrp, *(unsigned int *)data, 1);
739 			if ((*(unsigned int *)data == SIGINFO) &&
740 			    ((tp->t_lflag&NOKERNINFO) == 0))
741 				ttyinfo(tp);
742 			return(0);
743 		}
744 	}
745 	if (cmd == TIOCEXT) {
746 		/*
747 		 * When the EXTPROC bit is being toggled, we need
748 		 * to send an TIOCPKT_IOCTL if the packet driver
749 		 * is turned on.
750 		 */
751 		if (*(int *)data) {
752 			if (pti->pt_flags & PF_PKT) {
753 				pti->pt_send |= TIOCPKT_IOCTL;
754 				ptcwakeup(tp, FREAD);
755 			}
756 			tp->t_lflag |= EXTPROC;
757 		} else {
758 			if ((tp->t_lflag & EXTPROC) &&
759 			    (pti->pt_flags & PF_PKT)) {
760 				pti->pt_send |= TIOCPKT_IOCTL;
761 				ptcwakeup(tp, FREAD);
762 			}
763 			tp->t_lflag &= ~EXTPROC;
764 		}
765 		return(0);
766 	}
767 	error = (*linesw[tp->t_line].l_ioctl)(tp, cmd, data, flag, td);
768 	if (error == ENOIOCTL)
769 		 error = ttioctl(tp, cmd, data, flag);
770 	if (error == ENOIOCTL) {
771 		if (pti->pt_flags & PF_UCNTL &&
772 		    (cmd & ~0xff) == UIOCCMD(0)) {
773 			if (cmd & 0xff) {
774 				pti->pt_ucntl = (u_char)cmd;
775 				ptcwakeup(tp, FREAD);
776 			}
777 			return (0);
778 		}
779 		error = ENOTTY;
780 	}
781 	/*
782 	 * If external processing and packet mode send ioctl packet.
783 	 */
784 	if ((tp->t_lflag&EXTPROC) && (pti->pt_flags & PF_PKT)) {
785 		switch(cmd) {
786 		case TIOCSETA:
787 		case TIOCSETAW:
788 		case TIOCSETAF:
789 #ifdef COMPAT_43
790 		case TIOCSETP:
791 		case TIOCSETN:
792 #endif
793 #if defined(COMPAT_43) || defined(COMPAT_SUNOS)
794 		case TIOCSETC:
795 		case TIOCSLTC:
796 		case TIOCLBIS:
797 		case TIOCLBIC:
798 		case TIOCLSET:
799 #endif
800 			pti->pt_send |= TIOCPKT_IOCTL;
801 			ptcwakeup(tp, FREAD);
802 		default:
803 			break;
804 		}
805 	}
806 	stop = (tp->t_iflag & IXON) && CCEQ(cc[VSTOP], CTRL('s'))
807 		&& CCEQ(cc[VSTART], CTRL('q'));
808 	if (pti->pt_flags & PF_NOSTOP) {
809 		if (stop) {
810 			pti->pt_send &= ~TIOCPKT_NOSTOP;
811 			pti->pt_send |= TIOCPKT_DOSTOP;
812 			pti->pt_flags &= ~PF_NOSTOP;
813 			ptcwakeup(tp, FREAD);
814 		}
815 	} else {
816 		if (!stop) {
817 			pti->pt_send &= ~TIOCPKT_DOSTOP;
818 			pti->pt_send |= TIOCPKT_NOSTOP;
819 			pti->pt_flags |= PF_NOSTOP;
820 			ptcwakeup(tp, FREAD);
821 		}
822 	}
823 	return (error);
824 }
825 
826 
827 static void ptc_drvinit __P((void *unused));
828 
829 static void
830 ptc_drvinit(unused)
831 	void *unused;
832 {
833 	cdevsw_add(&pts_cdevsw);
834 	cdevsw_add(&ptc_cdevsw);
835 	/* XXX: Gross hack for DEVFS */
836 	/* XXX: DEVFS is no more, should this be removed? */
837 	ptyinit(0);
838 }
839 
840 SYSINIT(ptcdev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR_C,ptc_drvinit,NULL)
841