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tty_pty.c revision 1.73
      1  1.73  jdolecek /*	$NetBSD: tty_pty.c,v 1.73 2004/02/22 17:51:26 jdolecek Exp $	*/
      2  1.23       cgd 
      3   1.1       cgd /*
      4  1.22       cgd  * Copyright (c) 1982, 1986, 1989, 1993
      5  1.22       cgd  *	The Regents of the University of California.  All rights reserved.
      6   1.1       cgd  *
      7   1.1       cgd  * Redistribution and use in source and binary forms, with or without
      8   1.1       cgd  * modification, are permitted provided that the following conditions
      9   1.1       cgd  * are met:
     10   1.1       cgd  * 1. Redistributions of source code must retain the above copyright
     11   1.1       cgd  *    notice, this list of conditions and the following disclaimer.
     12   1.1       cgd  * 2. Redistributions in binary form must reproduce the above copyright
     13   1.1       cgd  *    notice, this list of conditions and the following disclaimer in the
     14   1.1       cgd  *    documentation and/or other materials provided with the distribution.
     15  1.72       agc  * 3. Neither the name of the University nor the names of its contributors
     16   1.1       cgd  *    may be used to endorse or promote products derived from this software
     17   1.1       cgd  *    without specific prior written permission.
     18   1.1       cgd  *
     19   1.1       cgd  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     20   1.1       cgd  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     21   1.1       cgd  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     22   1.1       cgd  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     23   1.1       cgd  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     24   1.1       cgd  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     25   1.1       cgd  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     26   1.1       cgd  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     27   1.1       cgd  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     28   1.1       cgd  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     29   1.1       cgd  * SUCH DAMAGE.
     30   1.1       cgd  *
     31  1.39      fvdl  *	@(#)tty_pty.c	8.4 (Berkeley) 2/20/95
     32   1.1       cgd  */
     33   1.1       cgd 
     34   1.1       cgd /*
     35   1.1       cgd  * Pseudo-teletype Driver
     36   1.1       cgd  * (Actually two drivers, requiring two entries in 'cdevsw')
     37   1.1       cgd  */
     38  1.57     lukem 
     39  1.57     lukem #include <sys/cdefs.h>
     40  1.73  jdolecek __KERNEL_RCSID(0, "$NetBSD: tty_pty.c,v 1.73 2004/02/22 17:51:26 jdolecek Exp $");
     41  1.41   thorpej 
     42  1.41   thorpej #include "opt_compat_sunos.h"
     43  1.41   thorpej 
     44  1.16   mycroft #include <sys/param.h>
     45  1.16   mycroft #include <sys/systm.h>
     46  1.16   mycroft #include <sys/ioctl.h>
     47  1.22       cgd #include <sys/proc.h>
     48  1.16   mycroft #include <sys/tty.h>
     49  1.16   mycroft #include <sys/file.h>
     50  1.16   mycroft #include <sys/uio.h>
     51  1.16   mycroft #include <sys/kernel.h>
     52  1.16   mycroft #include <sys/vnode.h>
     53  1.31  christos #include <sys/signalvar.h>
     54  1.31  christos #include <sys/uio.h>
     55  1.33  christos #include <sys/conf.h>
     56  1.38   mycroft #include <sys/poll.h>
     57  1.47  jdolecek #include <sys/malloc.h>
     58  1.31  christos 
     59  1.47  jdolecek #define	DEFAULT_NPTYS		16	/* default number of initial ptys */
     60  1.58       tls #define DEFAULT_MAXPTYS		992	/* default maximum number of ptys */
     61   1.1       cgd 
     62  1.37   mycroft /* Macros to clear/set/test flags. */
     63  1.37   mycroft #define	SET(t, f)	(t) |= (f)
     64  1.37   mycroft #define	CLR(t, f)	(t) &= ~((unsigned)(f))
     65  1.37   mycroft #define	ISSET(t, f)	((t) & (f))
     66  1.37   mycroft 
     67   1.1       cgd #define BUFSIZ 100		/* Chunk size iomoved to/from user */
     68   1.1       cgd 
     69   1.1       cgd /*
     70   1.1       cgd  * pts == /dev/tty[pqrs]?
     71   1.1       cgd  * ptc == /dev/pty[pqrs]?
     72   1.1       cgd  */
     73  1.27   mycroft struct	pt_softc {
     74  1.27   mycroft 	struct	tty *pt_tty;
     75   1.1       cgd 	int	pt_flags;
     76  1.22       cgd 	struct	selinfo pt_selr, pt_selw;
     77   1.1       cgd 	u_char	pt_send;
     78   1.1       cgd 	u_char	pt_ucntl;
     79  1.47  jdolecek };
     80  1.47  jdolecek 
     81  1.48  jdolecek static struct pt_softc **pt_softc = NULL;	/* pty array */
     82  1.48  jdolecek static int npty = 0;			/* for pstat -t */
     83  1.48  jdolecek static int maxptys = DEFAULT_MAXPTYS;	/* maximum number of ptys (sysctable) */
     84  1.48  jdolecek static struct simplelock pt_softc_mutex = SIMPLELOCK_INITIALIZER;
     85   1.1       cgd 
     86   1.1       cgd #define	PF_PKT		0x08		/* packet mode */
     87   1.1       cgd #define	PF_STOPPED	0x10		/* user told stopped */
     88   1.1       cgd #define	PF_REMOTE	0x20		/* remote and flow controlled input */
     89   1.1       cgd #define	PF_NOSTOP	0x40
     90   1.1       cgd #define PF_UCNTL	0x80		/* user control mode */
     91   1.1       cgd 
     92  1.31  christos void	ptyattach __P((int));
     93  1.31  christos void	ptcwakeup __P((struct tty *, int));
     94  1.31  christos void	ptsstart __P((struct tty *));
     95  1.48  jdolecek int	pty_maxptys __P((int, int));
     96  1.15   deraadt 
     97  1.47  jdolecek static struct pt_softc **ptyarralloc __P((int));
     98  1.71       dsl static int check_pty(int);
     99  1.47  jdolecek 
    100  1.63   gehenna dev_type_open(ptcopen);
    101  1.63   gehenna dev_type_close(ptcclose);
    102  1.63   gehenna dev_type_read(ptcread);
    103  1.63   gehenna dev_type_write(ptcwrite);
    104  1.63   gehenna dev_type_poll(ptcpoll);
    105  1.65  jdolecek dev_type_kqfilter(ptckqfilter);
    106  1.63   gehenna 
    107  1.63   gehenna dev_type_open(ptsopen);
    108  1.63   gehenna dev_type_close(ptsclose);
    109  1.63   gehenna dev_type_read(ptsread);
    110  1.63   gehenna dev_type_write(ptswrite);
    111  1.63   gehenna dev_type_stop(ptsstop);
    112  1.63   gehenna dev_type_poll(ptspoll);
    113  1.63   gehenna 
    114  1.63   gehenna dev_type_ioctl(ptyioctl);
    115  1.63   gehenna dev_type_tty(ptytty);
    116  1.63   gehenna 
    117  1.63   gehenna const struct cdevsw ptc_cdevsw = {
    118  1.63   gehenna 	ptcopen, ptcclose, ptcread, ptcwrite, ptyioctl,
    119  1.65  jdolecek 	nullstop, ptytty, ptcpoll, nommap, ptckqfilter, D_TTY
    120  1.63   gehenna };
    121  1.63   gehenna 
    122  1.63   gehenna const struct cdevsw pts_cdevsw = {
    123  1.63   gehenna 	ptsopen, ptsclose, ptsread, ptswrite, ptyioctl,
    124  1.65  jdolecek 	ptsstop, ptytty, ptspoll, nommap, ttykqfilter, D_TTY
    125  1.63   gehenna };
    126  1.63   gehenna 
    127  1.63   gehenna #if defined(pmax)
    128  1.63   gehenna const struct cdevsw ptc_ultrix_cdevsw = {
    129  1.63   gehenna 	ptcopen, ptcclose, ptcread, ptcwrite, ptyioctl,
    130  1.65  jdolecek 	nullstop, ptytty, ptcpoll, nommap, ptckqfilter, D_TTY
    131  1.63   gehenna };
    132  1.63   gehenna 
    133  1.63   gehenna const struct cdevsw pts_ultrix_cdevsw = {
    134  1.63   gehenna 	ptsopen, ptsclose, ptsread, ptswrite, ptyioctl,
    135  1.65  jdolecek 	ptsstop, ptytty, ptspoll, nommap, ttykqfilter, D_TTY
    136  1.63   gehenna };
    137  1.63   gehenna #endif /* defined(pmax) */
    138  1.63   gehenna 
    139  1.47  jdolecek /*
    140  1.48  jdolecek  * Allocate and zero array of nelem elements.
    141  1.47  jdolecek  */
    142  1.47  jdolecek static struct pt_softc **
    143  1.47  jdolecek ptyarralloc(nelem)
    144  1.47  jdolecek 	int nelem;
    145  1.47  jdolecek {
    146  1.47  jdolecek 	struct pt_softc **pt;
    147  1.47  jdolecek 	nelem += 10;
    148  1.71       dsl 	pt = malloc(nelem * sizeof *pt, M_DEVBUF, M_WAITOK | M_ZERO);
    149  1.47  jdolecek 	return pt;
    150  1.47  jdolecek }
    151  1.47  jdolecek 
    152  1.47  jdolecek /*
    153  1.47  jdolecek  * Check if the minor is correct and ensure necessary structures
    154  1.47  jdolecek  * are properly allocated.
    155  1.47  jdolecek  */
    156  1.47  jdolecek static int
    157  1.71       dsl check_pty(int ptn)
    158  1.47  jdolecek {
    159  1.47  jdolecek 	struct pt_softc *pti;
    160  1.47  jdolecek 
    161  1.71       dsl 	if (ptn >= npty) {
    162  1.71       dsl 		struct pt_softc **newpt, **oldpt;
    163  1.48  jdolecek 		int newnpty;
    164  1.47  jdolecek 
    165  1.48  jdolecek 		/* check if the requested pty can be granted */
    166  1.71       dsl 		if (ptn >= maxptys) {
    167  1.48  jdolecek 	    limit_reached:
    168  1.48  jdolecek 			tablefull("pty", "increase kern.maxptys");
    169  1.48  jdolecek 			return (ENXIO);
    170  1.48  jdolecek 		}
    171  1.47  jdolecek 
    172  1.71       dsl 		/* Allocate a larger pty array */
    173  1.71       dsl 		for (newnpty = npty; newnpty <= ptn;)
    174  1.71       dsl 			newnpty *= 2;
    175  1.71       dsl 		if (newnpty > maxptys)
    176  1.71       dsl 			newnpty = maxptys;
    177  1.71       dsl 		newpt = ptyarralloc(newnpty);
    178  1.71       dsl 
    179  1.47  jdolecek 		/*
    180  1.48  jdolecek 		 * Now grab the pty array mutex - we need to ensure
    181  1.47  jdolecek 		 * that the pty array is consistent while copying it's
    182  1.48  jdolecek 		 * content to newly allocated, larger space; we also
    183  1.48  jdolecek 		 * need to be safe against pty_maxptys().
    184  1.47  jdolecek 		 */
    185  1.48  jdolecek 		simple_lock(&pt_softc_mutex);
    186  1.48  jdolecek 
    187  1.71       dsl 		if (newnpty >= maxptys) {
    188  1.71       dsl 			/* limit cut away beneath us... */
    189  1.71       dsl 			newnpty = maxptys;
    190  1.71       dsl 			if (ptn >= newnpty) {
    191  1.54     enami 				simple_unlock(&pt_softc_mutex);
    192  1.71       dsl 				free(newpt, M_DEVBUF);
    193  1.48  jdolecek 				goto limit_reached;
    194  1.48  jdolecek 			}
    195  1.71       dsl 		}
    196  1.47  jdolecek 
    197  1.47  jdolecek 		/*
    198  1.48  jdolecek 		 * If the pty array was not enlarged while we were waiting
    199  1.48  jdolecek 		 * for mutex, copy current contents of pt_softc[] to newly
    200  1.48  jdolecek 		 * allocated array and start using the new bigger array.
    201  1.47  jdolecek 		 */
    202  1.71       dsl 		if (newnpty > npty) {
    203  1.47  jdolecek 			memcpy(newpt, pt_softc, npty*sizeof(struct pt_softc *));
    204  1.71       dsl 			oldpt = pt_softc;
    205  1.47  jdolecek 			pt_softc = newpt;
    206  1.47  jdolecek 			npty = newnpty;
    207  1.47  jdolecek 		} else {
    208  1.71       dsl 			/* was enlarged when waited for lock, free new space */
    209  1.71       dsl 			oldpt = newpt;
    210  1.47  jdolecek 		}
    211  1.48  jdolecek 
    212  1.48  jdolecek 		simple_unlock(&pt_softc_mutex);
    213  1.71       dsl 		free(oldpt, M_DEVBUF);
    214  1.47  jdolecek 	}
    215  1.71       dsl 
    216  1.47  jdolecek 	/*
    217  1.48  jdolecek 	 * If the entry is not yet allocated, allocate one. The mutex is
    218  1.48  jdolecek 	 * needed so that the state of pt_softc[] array is consistant
    219  1.71       dsl 	 * in case it has been lengthened above.
    220  1.47  jdolecek 	 */
    221  1.71       dsl 	if (!pt_softc[ptn]) {
    222  1.48  jdolecek 		MALLOC(pti, struct pt_softc *, sizeof(struct pt_softc),
    223  1.48  jdolecek 			M_DEVBUF, M_WAITOK);
    224  1.64  jdolecek 		memset(pti, 0, sizeof(struct pt_softc));
    225  1.48  jdolecek 
    226  1.48  jdolecek 	 	pti->pt_tty = ttymalloc();
    227  1.48  jdolecek 
    228  1.48  jdolecek 		simple_lock(&pt_softc_mutex);
    229  1.47  jdolecek 
    230  1.47  jdolecek 		/*
    231  1.48  jdolecek 		 * Check the entry again - it might have been
    232  1.48  jdolecek 		 * added while we were waiting for mutex.
    233  1.47  jdolecek 		 */
    234  1.71       dsl 		if (!pt_softc[ptn]) {
    235  1.47  jdolecek 			tty_attach(pti->pt_tty);
    236  1.71       dsl 			pt_softc[ptn] = pti;
    237  1.48  jdolecek 		} else {
    238  1.48  jdolecek 			ttyfree(pti->pt_tty);
    239  1.71       dsl 			free(pti, M_DEVBUF);
    240  1.47  jdolecek 		}
    241  1.48  jdolecek 
    242  1.48  jdolecek 		simple_unlock(&pt_softc_mutex);
    243  1.48  jdolecek 	}
    244  1.48  jdolecek 
    245  1.48  jdolecek 	return (0);
    246  1.48  jdolecek }
    247  1.48  jdolecek 
    248  1.48  jdolecek /*
    249  1.48  jdolecek  * Set maxpty in thread-safe way. Returns 0 in case of error, otherwise
    250  1.48  jdolecek  * new value of maxptys.
    251  1.48  jdolecek  */
    252  1.48  jdolecek int
    253  1.48  jdolecek pty_maxptys(newmax, set)
    254  1.48  jdolecek 	int newmax, set;
    255  1.48  jdolecek {
    256  1.48  jdolecek 	if (!set)
    257  1.48  jdolecek 		return (maxptys);
    258  1.48  jdolecek 
    259  1.48  jdolecek 	/*
    260  1.48  jdolecek 	 * We have to grab the pt_softc lock, so that we would pick correct
    261  1.48  jdolecek 	 * value of npty (might be modified in check_pty()).
    262  1.48  jdolecek 	 */
    263  1.48  jdolecek 	simple_lock(&pt_softc_mutex);
    264  1.48  jdolecek 
    265  1.71       dsl 	/*
    266  1.71       dsl 	 * The value cannot be set to value lower than the highest pty
    267  1.71       dsl 	 * number ever allocated.
    268  1.71       dsl 	 */
    269  1.71       dsl 	if (newmax >= npty)
    270  1.48  jdolecek 		maxptys = newmax;
    271  1.71       dsl 	else
    272  1.71       dsl 		newmax = 0;
    273  1.47  jdolecek 
    274  1.48  jdolecek 	simple_unlock(&pt_softc_mutex);
    275  1.48  jdolecek 
    276  1.71       dsl 	return newmax;
    277  1.47  jdolecek }
    278  1.47  jdolecek 
    279  1.22       cgd /*
    280  1.22       cgd  * Establish n (or default if n is 1) ptys in the system.
    281  1.22       cgd  */
    282  1.15   deraadt void
    283  1.15   deraadt ptyattach(n)
    284  1.15   deraadt 	int n;
    285  1.15   deraadt {
    286  1.22       cgd 	/* maybe should allow 0 => none? */
    287  1.22       cgd 	if (n <= 1)
    288  1.47  jdolecek 		n = DEFAULT_NPTYS;
    289  1.47  jdolecek 	pt_softc = ptyarralloc(n);
    290  1.22       cgd 	npty = n;
    291  1.15   deraadt }
    292   1.7    andrew 
    293   1.1       cgd /*ARGSUSED*/
    294  1.31  christos int
    295  1.70      fvdl ptsopen(dev, flag, devtype, p)
    296   1.1       cgd 	dev_t dev;
    297   1.7    andrew 	int flag, devtype;
    298  1.70      fvdl 	struct proc *p;
    299   1.1       cgd {
    300  1.27   mycroft 	struct pt_softc *pti;
    301  1.43  augustss 	struct tty *tp;
    302   1.1       cgd 	int error;
    303  1.71       dsl 	int ptn = minor(dev);
    304   1.1       cgd 
    305  1.71       dsl 	if ((error = check_pty(ptn)))
    306  1.47  jdolecek 		return (error);
    307  1.47  jdolecek 
    308  1.71       dsl 	pti = pt_softc[ptn];
    309  1.47  jdolecek 	tp = pti->pt_tty;
    310  1.47  jdolecek 
    311  1.37   mycroft 	if (!ISSET(tp->t_state, TS_ISOPEN)) {
    312   1.1       cgd 		ttychars(tp);		/* Set up default chars */
    313   1.1       cgd 		tp->t_iflag = TTYDEF_IFLAG;
    314   1.1       cgd 		tp->t_oflag = TTYDEF_OFLAG;
    315   1.1       cgd 		tp->t_lflag = TTYDEF_LFLAG;
    316   1.1       cgd 		tp->t_cflag = TTYDEF_CFLAG;
    317   1.1       cgd 		tp->t_ispeed = tp->t_ospeed = TTYDEF_SPEED;
    318   1.1       cgd 		ttsetwater(tp);		/* would be done in xxparam() */
    319  1.37   mycroft 	} else if (ISSET(tp->t_state, TS_XCLUDE) && p->p_ucred->cr_uid != 0)
    320   1.1       cgd 		return (EBUSY);
    321   1.1       cgd 	if (tp->t_oproc)			/* Ctrlr still around. */
    322  1.37   mycroft 		SET(tp->t_state, TS_CARR_ON);
    323  1.71       dsl 
    324  1.68        pk 	if (!ISSET(flag, O_NONBLOCK)) {
    325  1.68        pk 		TTY_LOCK(tp);
    326  1.40   mycroft 		while (!ISSET(tp->t_state, TS_CARR_ON)) {
    327  1.40   mycroft 			tp->t_wopen++;
    328  1.40   mycroft 			error = ttysleep(tp, &tp->t_rawq, TTIPRI | PCATCH,
    329  1.40   mycroft 			    ttopen, 0);
    330  1.40   mycroft 			tp->t_wopen--;
    331  1.68        pk 			if (error) {
    332  1.68        pk 				TTY_UNLOCK(tp);
    333  1.40   mycroft 				return (error);
    334  1.68        pk 			}
    335  1.40   mycroft 		}
    336  1.68        pk 		TTY_UNLOCK(tp);
    337  1.68        pk 	}
    338  1.50       eeh 	error = (*tp->t_linesw->l_open)(dev, tp);
    339   1.1       cgd 	ptcwakeup(tp, FREAD|FWRITE);
    340  1.22       cgd 	return (error);
    341   1.1       cgd }
    342   1.1       cgd 
    343  1.31  christos int
    344  1.70      fvdl ptsclose(dev, flag, mode, p)
    345   1.1       cgd 	dev_t dev;
    346   1.1       cgd 	int flag, mode;
    347  1.70      fvdl 	struct proc *p;
    348   1.1       cgd {
    349  1.47  jdolecek 	struct pt_softc *pti = pt_softc[minor(dev)];
    350  1.43  augustss 	struct tty *tp = pti->pt_tty;
    351  1.31  christos 	int error;
    352   1.1       cgd 
    353  1.50       eeh 	error = (*tp->t_linesw->l_close)(tp, flag);
    354  1.31  christos 	error |= ttyclose(tp);
    355   1.1       cgd 	ptcwakeup(tp, FREAD|FWRITE);
    356  1.31  christos 	return (error);
    357   1.1       cgd }
    358   1.1       cgd 
    359  1.31  christos int
    360   1.1       cgd ptsread(dev, uio, flag)
    361   1.1       cgd 	dev_t dev;
    362   1.1       cgd 	struct uio *uio;
    363   1.7    andrew 	int flag;
    364   1.1       cgd {
    365   1.1       cgd 	struct proc *p = curproc;
    366  1.47  jdolecek 	struct pt_softc *pti = pt_softc[minor(dev)];
    367  1.43  augustss 	struct tty *tp = pti->pt_tty;
    368   1.1       cgd 	int error = 0;
    369  1.68        pk 	int cc;
    370   1.1       cgd 
    371   1.1       cgd again:
    372   1.1       cgd 	if (pti->pt_flags & PF_REMOTE) {
    373   1.1       cgd 		while (isbackground(p, tp)) {
    374  1.51  jdolecek 			if (sigismasked(p, SIGTTIN) ||
    375   1.1       cgd 			    p->p_pgrp->pg_jobc == 0 ||
    376  1.22       cgd 			    p->p_flag & P_PPWAIT)
    377   1.1       cgd 				return (EIO);
    378   1.1       cgd 			pgsignal(p->p_pgrp, SIGTTIN, 1);
    379  1.68        pk 			TTY_LOCK(tp);
    380  1.35        pk 			error = ttysleep(tp, (caddr_t)&lbolt,
    381  1.68        pk 					 TTIPRI | PCATCH | PNORELOCK, ttybg, 0);
    382  1.31  christos 			if (error)
    383   1.1       cgd 				return (error);
    384   1.1       cgd 		}
    385  1.68        pk 		TTY_LOCK(tp);
    386   1.8   mycroft 		if (tp->t_canq.c_cc == 0) {
    387  1.68        pk 			if (flag & IO_NDELAY) {
    388  1.68        pk 				TTY_UNLOCK(tp);
    389   1.1       cgd 				return (EWOULDBLOCK);
    390  1.68        pk 			}
    391  1.31  christos 			error = ttysleep(tp, (caddr_t)&tp->t_canq,
    392  1.68        pk 					 TTIPRI | PCATCH | PNORELOCK, ttyin, 0);
    393  1.31  christos 			if (error)
    394   1.1       cgd 				return (error);
    395   1.1       cgd 			goto again;
    396   1.1       cgd 		}
    397  1.68        pk 		while(error == 0 && tp->t_canq.c_cc > 1 && uio->uio_resid > 0) {
    398  1.68        pk 			TTY_UNLOCK(tp);
    399  1.68        pk 			error = ureadc(getc(&tp->t_canq), uio);
    400  1.68        pk 			TTY_LOCK(tp);
    401  1.68        pk 			/* Re-check terminal state here? */
    402  1.68        pk 		}
    403   1.8   mycroft 		if (tp->t_canq.c_cc == 1)
    404   1.8   mycroft 			(void) getc(&tp->t_canq);
    405  1.68        pk 		cc = tp->t_canq.c_cc;
    406  1.68        pk 		TTY_UNLOCK(tp);
    407  1.68        pk 		if (cc)
    408   1.1       cgd 			return (error);
    409   1.1       cgd 	} else
    410   1.1       cgd 		if (tp->t_oproc)
    411  1.50       eeh 			error = (*tp->t_linesw->l_read)(tp, uio, flag);
    412   1.1       cgd 	ptcwakeup(tp, FWRITE);
    413   1.1       cgd 	return (error);
    414   1.1       cgd }
    415   1.1       cgd 
    416   1.1       cgd /*
    417   1.1       cgd  * Write to pseudo-tty.
    418   1.1       cgd  * Wakeups of controlling tty will happen
    419   1.1       cgd  * indirectly, when tty driver calls ptsstart.
    420   1.1       cgd  */
    421  1.31  christos int
    422   1.1       cgd ptswrite(dev, uio, flag)
    423   1.1       cgd 	dev_t dev;
    424   1.1       cgd 	struct uio *uio;
    425   1.7    andrew 	int flag;
    426   1.1       cgd {
    427  1.47  jdolecek 	struct pt_softc *pti = pt_softc[minor(dev)];
    428  1.43  augustss 	struct tty *tp = pti->pt_tty;
    429   1.1       cgd 
    430   1.1       cgd 	if (tp->t_oproc == 0)
    431   1.1       cgd 		return (EIO);
    432  1.50       eeh 	return ((*tp->t_linesw->l_write)(tp, uio, flag));
    433  1.56       scw }
    434  1.56       scw 
    435  1.56       scw /*
    436  1.56       scw  * Poll pseudo-tty.
    437  1.56       scw  */
    438  1.56       scw int
    439  1.70      fvdl ptspoll(dev, events, p)
    440  1.56       scw 	dev_t dev;
    441  1.56       scw 	int events;
    442  1.70      fvdl 	struct proc *p;
    443  1.56       scw {
    444  1.56       scw 	struct pt_softc *pti = pt_softc[minor(dev)];
    445  1.56       scw 	struct tty *tp = pti->pt_tty;
    446  1.56       scw 
    447  1.56       scw 	if (tp->t_oproc == 0)
    448  1.56       scw 		return (EIO);
    449  1.56       scw 
    450  1.70      fvdl 	return ((*tp->t_linesw->l_poll)(tp, events, p));
    451   1.1       cgd }
    452   1.1       cgd 
    453   1.1       cgd /*
    454   1.1       cgd  * Start output on pseudo-tty.
    455  1.38   mycroft  * Wake up process polling or sleeping for input from controlling tty.
    456  1.68        pk  * Called with tty slock held.
    457   1.1       cgd  */
    458  1.12   deraadt void
    459   1.1       cgd ptsstart(tp)
    460   1.1       cgd 	struct tty *tp;
    461   1.1       cgd {
    462  1.47  jdolecek 	struct pt_softc *pti = pt_softc[minor(tp->t_dev)];
    463   1.1       cgd 
    464  1.37   mycroft 	if (ISSET(tp->t_state, TS_TTSTOP))
    465  1.12   deraadt 		return;
    466   1.1       cgd 	if (pti->pt_flags & PF_STOPPED) {
    467   1.1       cgd 		pti->pt_flags &= ~PF_STOPPED;
    468   1.1       cgd 		pti->pt_send = TIOCPKT_START;
    469   1.1       cgd 	}
    470  1.68        pk 
    471  1.73  jdolecek 	selnotify(&pti->pt_selr, NOTE_SUBMIT);
    472  1.68        pk 	wakeup((caddr_t)&tp->t_outq.c_cf);
    473   1.1       cgd }
    474   1.1       cgd 
    475  1.68        pk /*
    476  1.68        pk  * Stop output.
    477  1.68        pk  * Called with tty slock held.
    478  1.68        pk  */
    479  1.36   mycroft void
    480  1.31  christos ptsstop(tp, flush)
    481  1.43  augustss 	struct tty *tp;
    482  1.31  christos 	int flush;
    483  1.31  christos {
    484  1.47  jdolecek 	struct pt_softc *pti = pt_softc[minor(tp->t_dev)];
    485  1.31  christos 
    486  1.31  christos 	/* note: FLUSHREAD and FLUSHWRITE already ok */
    487  1.31  christos 	if (flush == 0) {
    488  1.31  christos 		flush = TIOCPKT_STOP;
    489  1.31  christos 		pti->pt_flags |= PF_STOPPED;
    490  1.31  christos 	} else
    491  1.31  christos 		pti->pt_flags &= ~PF_STOPPED;
    492  1.31  christos 	pti->pt_send |= flush;
    493  1.68        pk 
    494  1.31  christos 	/* change of perspective */
    495  1.68        pk 	if (flush & FREAD) {
    496  1.73  jdolecek 		selnotify(&pti->pt_selw, NOTE_SUBMIT);
    497  1.68        pk 		wakeup((caddr_t)&tp->t_rawq.c_cf);
    498  1.68        pk 	}
    499  1.68        pk 	if (flush & FWRITE) {
    500  1.73  jdolecek 		selnotify(&pti->pt_selr, NOTE_SUBMIT);
    501  1.68        pk 		wakeup((caddr_t)&tp->t_outq.c_cf);
    502  1.68        pk 	}
    503  1.31  christos }
    504  1.31  christos 
    505  1.31  christos void
    506   1.1       cgd ptcwakeup(tp, flag)
    507   1.1       cgd 	struct tty *tp;
    508   1.7    andrew 	int flag;
    509   1.1       cgd {
    510  1.47  jdolecek 	struct pt_softc *pti = pt_softc[minor(tp->t_dev)];
    511   1.1       cgd 
    512  1.68        pk 	TTY_LOCK(tp);
    513   1.1       cgd 	if (flag & FREAD) {
    514  1.73  jdolecek 		selnotify(&pti->pt_selr, NOTE_SUBMIT);
    515  1.22       cgd 		wakeup((caddr_t)&tp->t_outq.c_cf);
    516   1.1       cgd 	}
    517   1.1       cgd 	if (flag & FWRITE) {
    518  1.73  jdolecek 		selnotify(&pti->pt_selw, NOTE_SUBMIT);
    519   1.8   mycroft 		wakeup((caddr_t)&tp->t_rawq.c_cf);
    520   1.1       cgd 	}
    521  1.68        pk 	TTY_UNLOCK(tp);
    522   1.1       cgd }
    523   1.1       cgd 
    524   1.1       cgd /*ARGSUSED*/
    525  1.25   mycroft int
    526  1.70      fvdl ptcopen(dev, flag, devtype, p)
    527   1.1       cgd 	dev_t dev;
    528   1.1       cgd 	int flag, devtype;
    529  1.70      fvdl 	struct proc *p;
    530   1.1       cgd {
    531  1.27   mycroft 	struct pt_softc *pti;
    532  1.43  augustss 	struct tty *tp;
    533  1.47  jdolecek 	int error;
    534  1.71       dsl 	int ptn = minor(dev);
    535  1.47  jdolecek 
    536  1.71       dsl 	if ((error = check_pty(ptn)))
    537  1.47  jdolecek 		return (error);
    538  1.47  jdolecek 
    539  1.71       dsl 	pti = pt_softc[ptn];
    540  1.47  jdolecek 	tp = pti->pt_tty;
    541   1.1       cgd 
    542  1.71       dsl 	TTY_LOCK(tp);
    543  1.71       dsl 	if (tp->t_oproc) {
    544  1.71       dsl 		TTY_UNLOCK(tp);
    545   1.1       cgd 		return (EIO);
    546  1.71       dsl 	}
    547   1.1       cgd 	tp->t_oproc = ptsstart;
    548  1.71       dsl 	TTY_UNLOCK(tp);
    549  1.50       eeh 	(void)(*tp->t_linesw->l_modem)(tp, 1);
    550  1.37   mycroft 	CLR(tp->t_lflag, EXTPROC);
    551  1.22       cgd 	pti->pt_flags = 0;
    552   1.1       cgd 	pti->pt_send = 0;
    553   1.1       cgd 	pti->pt_ucntl = 0;
    554   1.1       cgd 	return (0);
    555   1.1       cgd }
    556   1.1       cgd 
    557  1.31  christos /*ARGSUSED*/
    558  1.25   mycroft int
    559  1.70      fvdl ptcclose(dev, flag, devtype, p)
    560   1.1       cgd 	dev_t dev;
    561  1.31  christos 	int flag, devtype;
    562  1.70      fvdl 	struct proc *p;
    563   1.1       cgd {
    564  1.47  jdolecek 	struct pt_softc *pti = pt_softc[minor(dev)];
    565  1.43  augustss 	struct tty *tp = pti->pt_tty;
    566   1.1       cgd 
    567  1.50       eeh 	(void)(*tp->t_linesw->l_modem)(tp, 0);
    568  1.37   mycroft 	CLR(tp->t_state, TS_CARR_ON);
    569  1.71       dsl 	TTY_LOCK(tp);
    570   1.1       cgd 	tp->t_oproc = 0;		/* mark closed */
    571  1.71       dsl 	TTY_UNLOCK(tp);
    572   1.2       cgd 	return (0);
    573   1.1       cgd }
    574   1.1       cgd 
    575  1.31  christos int
    576   1.1       cgd ptcread(dev, uio, flag)
    577   1.1       cgd 	dev_t dev;
    578   1.1       cgd 	struct uio *uio;
    579   1.7    andrew 	int flag;
    580   1.1       cgd {
    581  1.47  jdolecek 	struct pt_softc *pti = pt_softc[minor(dev)];
    582  1.43  augustss 	struct tty *tp = pti->pt_tty;
    583  1.67    simonb 	u_char buf[BUFSIZ];
    584   1.1       cgd 	int error = 0, cc;
    585   1.1       cgd 
    586   1.1       cgd 	/*
    587   1.1       cgd 	 * We want to block until the slave
    588   1.1       cgd 	 * is open, and there's something to read;
    589   1.1       cgd 	 * but if we lost the slave or we're NBIO,
    590   1.1       cgd 	 * then return the appropriate error instead.
    591   1.1       cgd 	 */
    592  1.68        pk 	TTY_LOCK(tp);
    593   1.1       cgd 	for (;;) {
    594  1.37   mycroft 		if (ISSET(tp->t_state, TS_ISOPEN)) {
    595  1.71       dsl 			if (pti->pt_flags & PF_PKT && pti->pt_send) {
    596  1.68        pk 				TTY_UNLOCK(tp);
    597   1.1       cgd 				error = ureadc((int)pti->pt_send, uio);
    598   1.1       cgd 				if (error)
    599   1.1       cgd 					return (error);
    600  1.68        pk 				/*
    601  1.68        pk 				 * Since we don't have the tty locked, there's
    602  1.68        pk 				 * a risk of messing up `t_termios'. This is
    603  1.68        pk 				 * relevant only if the tty got closed and then
    604  1.68        pk 				 * opened again while we were out uiomoving.
    605  1.68        pk 				 */
    606   1.1       cgd 				if (pti->pt_send & TIOCPKT_IOCTL) {
    607  1.22       cgd 					cc = min(uio->uio_resid,
    608   1.1       cgd 						sizeof(tp->t_termios));
    609  1.31  christos 					uiomove((caddr_t) &tp->t_termios,
    610  1.31  christos 						cc, uio);
    611   1.1       cgd 				}
    612   1.1       cgd 				pti->pt_send = 0;
    613   1.1       cgd 				return (0);
    614   1.1       cgd 			}
    615  1.71       dsl 			if (pti->pt_flags & PF_UCNTL && pti->pt_ucntl) {
    616  1.68        pk 				TTY_UNLOCK(tp);
    617   1.1       cgd 				error = ureadc((int)pti->pt_ucntl, uio);
    618   1.1       cgd 				if (error)
    619   1.1       cgd 					return (error);
    620   1.1       cgd 				pti->pt_ucntl = 0;
    621   1.1       cgd 				return (0);
    622   1.1       cgd 			}
    623  1.37   mycroft 			if (tp->t_outq.c_cc && !ISSET(tp->t_state, TS_TTSTOP))
    624   1.1       cgd 				break;
    625   1.1       cgd 		}
    626  1.68        pk 		if (!ISSET(tp->t_state, TS_CARR_ON)) {
    627  1.68        pk 			error = 0;	/* EOF */
    628  1.68        pk 			goto out;
    629  1.68        pk 		}
    630  1.68        pk 		if (flag & IO_NDELAY) {
    631  1.68        pk 			error = EWOULDBLOCK;
    632  1.68        pk 			goto out;
    633  1.68        pk 		}
    634  1.68        pk 		error = ltsleep((caddr_t)&tp->t_outq.c_cf, TTIPRI | PCATCH,
    635  1.68        pk 				ttyin, 0, &tp->t_slock);
    636  1.31  christos 		if (error)
    637  1.68        pk 			goto out;
    638   1.1       cgd 	}
    639  1.68        pk 
    640  1.68        pk 	if (pti->pt_flags & (PF_PKT|PF_UCNTL)) {
    641  1.68        pk 		TTY_UNLOCK(tp);
    642   1.1       cgd 		error = ureadc(0, uio);
    643  1.68        pk 		TTY_LOCK(tp);
    644  1.68        pk 		if (error == 0 && !ISSET(tp->t_state, TS_ISOPEN))
    645  1.68        pk 			error = EIO;
    646  1.68        pk 	}
    647   1.1       cgd 	while (uio->uio_resid > 0 && error == 0) {
    648  1.22       cgd 		cc = q_to_b(&tp->t_outq, buf, min(uio->uio_resid, BUFSIZ));
    649   1.1       cgd 		if (cc <= 0)
    650   1.1       cgd 			break;
    651  1.68        pk 		TTY_UNLOCK(tp);
    652   1.1       cgd 		error = uiomove(buf, cc, uio);
    653  1.68        pk 		TTY_LOCK(tp);
    654  1.68        pk 		if (error == 0 && !ISSET(tp->t_state, TS_ISOPEN))
    655  1.68        pk 			error = EIO;
    656   1.1       cgd 	}
    657  1.68        pk 
    658   1.8   mycroft 	if (tp->t_outq.c_cc <= tp->t_lowat) {
    659  1.37   mycroft 		if (ISSET(tp->t_state, TS_ASLEEP)) {
    660  1.37   mycroft 			CLR(tp->t_state, TS_ASLEEP);
    661   1.8   mycroft 			wakeup((caddr_t)&tp->t_outq);
    662   1.1       cgd 		}
    663  1.73  jdolecek 		selnotify(&tp->t_wsel, NOTE_SUBMIT);
    664   1.1       cgd 	}
    665  1.68        pk out:
    666  1.68        pk 	TTY_UNLOCK(tp);
    667   1.1       cgd 	return (error);
    668   1.1       cgd }
    669   1.1       cgd 
    670   1.1       cgd 
    671  1.31  christos int
    672   1.1       cgd ptcwrite(dev, uio, flag)
    673   1.1       cgd 	dev_t dev;
    674  1.43  augustss 	struct uio *uio;
    675   1.7    andrew 	int flag;
    676   1.1       cgd {
    677  1.47  jdolecek 	struct pt_softc *pti = pt_softc[minor(dev)];
    678  1.43  augustss 	struct tty *tp = pti->pt_tty;
    679  1.43  augustss 	u_char *cp = NULL;
    680  1.43  augustss 	int cc = 0;
    681   1.1       cgd 	u_char locbuf[BUFSIZ];
    682   1.1       cgd 	int cnt = 0;
    683   1.1       cgd 	int error = 0;
    684   1.1       cgd 
    685   1.1       cgd again:
    686  1.68        pk 	TTY_LOCK(tp);
    687  1.37   mycroft 	if (!ISSET(tp->t_state, TS_ISOPEN))
    688   1.1       cgd 		goto block;
    689   1.1       cgd 	if (pti->pt_flags & PF_REMOTE) {
    690   1.8   mycroft 		if (tp->t_canq.c_cc)
    691   1.1       cgd 			goto block;
    692   1.8   mycroft 		while (uio->uio_resid > 0 && tp->t_canq.c_cc < TTYHOG - 1) {
    693   1.1       cgd 			if (cc == 0) {
    694   1.1       cgd 				cc = min(uio->uio_resid, BUFSIZ);
    695   1.8   mycroft 				cc = min(cc, TTYHOG - 1 - tp->t_canq.c_cc);
    696   1.1       cgd 				cp = locbuf;
    697  1.68        pk 				TTY_UNLOCK(tp);
    698   1.1       cgd 				error = uiomove((caddr_t)cp, cc, uio);
    699   1.1       cgd 				if (error)
    700   1.1       cgd 					return (error);
    701  1.68        pk 				TTY_LOCK(tp);
    702   1.1       cgd 				/* check again for safety */
    703  1.68        pk 				if (!ISSET(tp->t_state, TS_ISOPEN)) {
    704  1.68        pk 					error = EIO;
    705  1.68        pk 					goto out;
    706  1.68        pk 				}
    707   1.1       cgd 			}
    708   1.1       cgd 			if (cc)
    709  1.67    simonb 				(void) b_to_q(cp, cc, &tp->t_canq);
    710   1.1       cgd 			cc = 0;
    711   1.1       cgd 		}
    712   1.8   mycroft 		(void) putc(0, &tp->t_canq);
    713   1.1       cgd 		ttwakeup(tp);
    714   1.8   mycroft 		wakeup((caddr_t)&tp->t_canq);
    715  1.68        pk 		error = 0;
    716  1.68        pk 		goto out;
    717   1.1       cgd 	}
    718   1.1       cgd 	while (uio->uio_resid > 0) {
    719   1.1       cgd 		if (cc == 0) {
    720   1.1       cgd 			cc = min(uio->uio_resid, BUFSIZ);
    721   1.1       cgd 			cp = locbuf;
    722  1.68        pk 			TTY_UNLOCK(tp);
    723   1.1       cgd 			error = uiomove((caddr_t)cp, cc, uio);
    724   1.1       cgd 			if (error)
    725   1.1       cgd 				return (error);
    726  1.68        pk 			TTY_LOCK(tp);
    727   1.1       cgd 			/* check again for safety */
    728  1.68        pk 			if (!ISSET(tp->t_state, TS_ISOPEN)) {
    729  1.68        pk 				error = EIO;
    730  1.68        pk 				goto out;
    731  1.68        pk 			}
    732   1.1       cgd 		}
    733   1.1       cgd 		while (cc > 0) {
    734   1.8   mycroft 			if ((tp->t_rawq.c_cc + tp->t_canq.c_cc) >= TTYHOG - 2 &&
    735  1.59  christos 			   (tp->t_canq.c_cc > 0 || !ISSET(tp->t_lflag, ICANON))) {
    736   1.8   mycroft 				wakeup((caddr_t)&tp->t_rawq);
    737   1.1       cgd 				goto block;
    738   1.1       cgd 			}
    739  1.68        pk 			/* XXX - should change l_rint to be called with lock
    740  1.68        pk 			 *	 see also tty.c:ttyinput_wlock()
    741  1.68        pk 			 */
    742  1.68        pk 			TTY_UNLOCK(tp);
    743  1.50       eeh 			(*tp->t_linesw->l_rint)(*cp++, tp);
    744  1.68        pk 			TTY_LOCK(tp);
    745   1.1       cgd 			cnt++;
    746   1.1       cgd 			cc--;
    747   1.1       cgd 		}
    748   1.1       cgd 		cc = 0;
    749   1.1       cgd 	}
    750  1.68        pk 	error = 0;
    751  1.68        pk 	goto out;
    752  1.68        pk 
    753   1.1       cgd block:
    754   1.1       cgd 	/*
    755   1.1       cgd 	 * Come here to wait for slave to open, for space
    756   1.1       cgd 	 * in outq, or space in rawq.
    757   1.1       cgd 	 */
    758  1.68        pk 	if (!ISSET(tp->t_state, TS_CARR_ON)) {
    759  1.68        pk 		error = EIO;
    760  1.68        pk 		goto out;
    761  1.68        pk 	}
    762   1.1       cgd 	if (flag & IO_NDELAY) {
    763   1.1       cgd 		/* adjust for data copied in but not written */
    764   1.1       cgd 		uio->uio_resid += cc;
    765  1.68        pk 		error = cnt == 0 ? EWOULDBLOCK : 0;
    766  1.68        pk 		goto out;
    767   1.1       cgd 	}
    768  1.68        pk 	error = ltsleep((caddr_t)&tp->t_rawq.c_cf, TTOPRI | PCATCH | PNORELOCK,
    769  1.68        pk 		       ttyout, 0, &tp->t_slock);
    770  1.31  christos 	if (error) {
    771   1.1       cgd 		/* adjust for data copied in but not written */
    772   1.1       cgd 		uio->uio_resid += cc;
    773   1.1       cgd 		return (error);
    774   1.1       cgd 	}
    775   1.1       cgd 	goto again;
    776  1.68        pk 
    777  1.68        pk out:
    778  1.68        pk 	TTY_UNLOCK(tp);
    779  1.68        pk 	return (error);
    780  1.29   mycroft }
    781  1.29   mycroft 
    782  1.31  christos int
    783  1.70      fvdl ptcpoll(dev, events, p)
    784  1.31  christos 	dev_t dev;
    785  1.38   mycroft 	int events;
    786  1.70      fvdl 	struct proc *p;
    787  1.31  christos {
    788  1.47  jdolecek 	struct pt_softc *pti = pt_softc[minor(dev)];
    789  1.43  augustss 	struct tty *tp = pti->pt_tty;
    790  1.38   mycroft 	int revents = 0;
    791  1.38   mycroft 	int s = splsoftclock();
    792  1.31  christos 
    793  1.38   mycroft 	if (events & (POLLIN | POLLRDNORM))
    794  1.37   mycroft 		if (ISSET(tp->t_state, TS_ISOPEN) &&
    795  1.38   mycroft 		    ((tp->t_outq.c_cc > 0 && !ISSET(tp->t_state, TS_TTSTOP)) ||
    796  1.38   mycroft 		     ((pti->pt_flags & PF_PKT) && pti->pt_send) ||
    797  1.38   mycroft 		     ((pti->pt_flags & PF_UCNTL) && pti->pt_ucntl)))
    798  1.38   mycroft 			revents |= events & (POLLIN | POLLRDNORM);
    799  1.31  christos 
    800  1.38   mycroft 	if (events & (POLLOUT | POLLWRNORM))
    801  1.37   mycroft 		if (ISSET(tp->t_state, TS_ISOPEN) &&
    802  1.38   mycroft 		    ((pti->pt_flags & PF_REMOTE) ?
    803  1.38   mycroft 		     (tp->t_canq.c_cc == 0) :
    804  1.38   mycroft 		     ((tp->t_rawq.c_cc + tp->t_canq.c_cc < TTYHOG-2) ||
    805  1.59  christos 		      (tp->t_canq.c_cc == 0 && ISSET(tp->t_lflag, ICANON)))))
    806  1.38   mycroft 			revents |= events & (POLLOUT | POLLWRNORM);
    807  1.31  christos 
    808  1.38   mycroft 	if (events & POLLHUP)
    809  1.38   mycroft 		if (!ISSET(tp->t_state, TS_CARR_ON))
    810  1.38   mycroft 			revents |= POLLHUP;
    811  1.31  christos 
    812  1.38   mycroft 	if (revents == 0) {
    813  1.38   mycroft 		if (events & (POLLIN | POLLHUP | POLLRDNORM))
    814  1.70      fvdl 			selrecord(p, &pti->pt_selr);
    815  1.31  christos 
    816  1.38   mycroft 		if (events & (POLLOUT | POLLWRNORM))
    817  1.70      fvdl 			selrecord(p, &pti->pt_selw);
    818  1.31  christos 	}
    819  1.38   mycroft 
    820  1.38   mycroft 	splx(s);
    821  1.38   mycroft 	return (revents);
    822  1.31  christos }
    823  1.31  christos 
    824  1.65  jdolecek static void
    825  1.65  jdolecek filt_ptcrdetach(struct knote *kn)
    826  1.65  jdolecek {
    827  1.65  jdolecek 	struct pt_softc *pti;
    828  1.65  jdolecek 	int		s;
    829  1.65  jdolecek 
    830  1.65  jdolecek 	pti = kn->kn_hook;
    831  1.65  jdolecek 	s = spltty();
    832  1.66  christos 	SLIST_REMOVE(&pti->pt_selr.sel_klist, kn, knote, kn_selnext);
    833  1.65  jdolecek 	splx(s);
    834  1.65  jdolecek }
    835  1.65  jdolecek 
    836  1.65  jdolecek static int
    837  1.65  jdolecek filt_ptcread(struct knote *kn, long hint)
    838  1.65  jdolecek {
    839  1.65  jdolecek 	struct pt_softc *pti;
    840  1.65  jdolecek 	struct tty	*tp;
    841  1.65  jdolecek 	int canread;
    842  1.65  jdolecek 
    843  1.65  jdolecek 	pti = kn->kn_hook;
    844  1.65  jdolecek 	tp = pti->pt_tty;
    845  1.65  jdolecek 
    846  1.65  jdolecek 	canread = (ISSET(tp->t_state, TS_ISOPEN) &&
    847  1.65  jdolecek 		    ((tp->t_outq.c_cc > 0 && !ISSET(tp->t_state, TS_TTSTOP)) ||
    848  1.65  jdolecek 		     ((pti->pt_flags & PF_PKT) && pti->pt_send) ||
    849  1.65  jdolecek 		     ((pti->pt_flags & PF_UCNTL) && pti->pt_ucntl)));
    850  1.65  jdolecek 
    851  1.65  jdolecek 	if (canread) {
    852  1.65  jdolecek 		/*
    853  1.65  jdolecek 		 * c_cc is number of characters after output post-processing;
    854  1.65  jdolecek 		 * the amount of data actually read(2) depends on
    855  1.65  jdolecek 		 * setting of input flags for the terminal.
    856  1.65  jdolecek 		 */
    857  1.65  jdolecek 		kn->kn_data = tp->t_outq.c_cc;
    858  1.65  jdolecek 		if (((pti->pt_flags & PF_PKT) && pti->pt_send) ||
    859  1.65  jdolecek 		    ((pti->pt_flags & PF_UCNTL) && pti->pt_ucntl))
    860  1.65  jdolecek 			kn->kn_data++;
    861  1.65  jdolecek 	}
    862  1.65  jdolecek 
    863  1.65  jdolecek 	return (canread);
    864  1.65  jdolecek }
    865  1.65  jdolecek 
    866  1.65  jdolecek static void
    867  1.65  jdolecek filt_ptcwdetach(struct knote *kn)
    868  1.65  jdolecek {
    869  1.65  jdolecek 	struct pt_softc *pti;
    870  1.65  jdolecek 	int		s;
    871  1.65  jdolecek 
    872  1.65  jdolecek 	pti = kn->kn_hook;
    873  1.65  jdolecek 	s = spltty();
    874  1.66  christos 	SLIST_REMOVE(&pti->pt_selw.sel_klist, kn, knote, kn_selnext);
    875  1.65  jdolecek 	splx(s);
    876  1.65  jdolecek }
    877  1.65  jdolecek 
    878  1.65  jdolecek static int
    879  1.65  jdolecek filt_ptcwrite(struct knote *kn, long hint)
    880  1.65  jdolecek {
    881  1.65  jdolecek 	struct pt_softc *pti;
    882  1.65  jdolecek 	struct tty	*tp;
    883  1.65  jdolecek 	int canwrite;
    884  1.65  jdolecek 	int nwrite;
    885  1.65  jdolecek 
    886  1.65  jdolecek 	pti = kn->kn_hook;
    887  1.65  jdolecek 	tp = pti->pt_tty;
    888  1.65  jdolecek 
    889  1.65  jdolecek 	canwrite = (ISSET(tp->t_state, TS_ISOPEN) &&
    890  1.65  jdolecek 		    ((pti->pt_flags & PF_REMOTE) ?
    891  1.65  jdolecek 		     (tp->t_canq.c_cc == 0) :
    892  1.65  jdolecek 		     ((tp->t_rawq.c_cc + tp->t_canq.c_cc < TTYHOG-2) ||
    893  1.65  jdolecek 		      (tp->t_canq.c_cc == 0 && ISSET(tp->t_lflag, ICANON)))));
    894  1.65  jdolecek 
    895  1.65  jdolecek 	if (canwrite) {
    896  1.65  jdolecek 		if (pti->pt_flags & PF_REMOTE)
    897  1.65  jdolecek 			nwrite = tp->t_canq.c_cn;
    898  1.65  jdolecek 		else {
    899  1.65  jdolecek 			/* this is guaranteed to be > 0 due to above check */
    900  1.65  jdolecek 			nwrite = tp->t_canq.c_cn
    901  1.65  jdolecek 				- (tp->t_rawq.c_cc + tp->t_canq.c_cc);
    902  1.65  jdolecek 		}
    903  1.65  jdolecek 		kn->kn_data = nwrite;
    904  1.65  jdolecek 	}
    905  1.65  jdolecek 
    906  1.65  jdolecek 	return (canwrite);
    907  1.65  jdolecek }
    908  1.65  jdolecek 
    909  1.65  jdolecek static const struct filterops ptcread_filtops =
    910  1.65  jdolecek 	{ 1, NULL, filt_ptcrdetach, filt_ptcread };
    911  1.65  jdolecek static const struct filterops ptcwrite_filtops =
    912  1.65  jdolecek 	{ 1, NULL, filt_ptcwdetach, filt_ptcwrite };
    913  1.65  jdolecek 
    914  1.65  jdolecek int
    915  1.65  jdolecek ptckqfilter(dev_t dev, struct knote *kn)
    916  1.65  jdolecek {
    917  1.65  jdolecek 	struct pt_softc *pti = pt_softc[minor(dev)];
    918  1.65  jdolecek 	struct klist	*klist;
    919  1.65  jdolecek 	int		s;
    920  1.65  jdolecek 
    921  1.65  jdolecek 	switch (kn->kn_filter) {
    922  1.65  jdolecek 	case EVFILT_READ:
    923  1.66  christos 		klist = &pti->pt_selr.sel_klist;
    924  1.65  jdolecek 		kn->kn_fop = &ptcread_filtops;
    925  1.65  jdolecek 		break;
    926  1.65  jdolecek 	case EVFILT_WRITE:
    927  1.66  christos 		klist = &pti->pt_selw.sel_klist;
    928  1.65  jdolecek 		kn->kn_fop = &ptcwrite_filtops;
    929  1.65  jdolecek 		break;
    930  1.65  jdolecek 	default:
    931  1.65  jdolecek 		return (1);
    932  1.65  jdolecek 	}
    933  1.65  jdolecek 
    934  1.65  jdolecek 	kn->kn_hook = pti;
    935  1.65  jdolecek 
    936  1.65  jdolecek 	s = spltty();
    937  1.65  jdolecek 	SLIST_INSERT_HEAD(klist, kn, kn_selnext);
    938  1.65  jdolecek 	splx(s);
    939  1.65  jdolecek 
    940  1.65  jdolecek 	return (0);
    941  1.65  jdolecek }
    942  1.31  christos 
    943  1.29   mycroft struct tty *
    944  1.29   mycroft ptytty(dev)
    945  1.29   mycroft 	dev_t dev;
    946  1.29   mycroft {
    947  1.47  jdolecek 	struct pt_softc *pti = pt_softc[minor(dev)];
    948  1.43  augustss 	struct tty *tp = pti->pt_tty;
    949  1.29   mycroft 
    950  1.29   mycroft 	return (tp);
    951   1.1       cgd }
    952   1.1       cgd 
    953   1.1       cgd /*ARGSUSED*/
    954  1.31  christos int
    955  1.70      fvdl ptyioctl(dev, cmd, data, flag, p)
    956  1.18   mycroft 	dev_t dev;
    957  1.24       cgd 	u_long cmd;
    958   1.1       cgd 	caddr_t data;
    959  1.18   mycroft 	int flag;
    960  1.70      fvdl 	struct proc *p;
    961   1.1       cgd {
    962  1.47  jdolecek 	struct pt_softc *pti = pt_softc[minor(dev)];
    963  1.43  augustss 	struct tty *tp = pti->pt_tty;
    964  1.63   gehenna 	const struct cdevsw *cdev;
    965  1.43  augustss 	u_char *cc = tp->t_cc;
    966  1.44      fvdl 	int stop, error, sig;
    967   1.1       cgd 
    968  1.63   gehenna 	cdev = cdevsw_lookup(dev);
    969   1.1       cgd 	/*
    970   1.1       cgd 	 * IF CONTROLLER STTY THEN MUST FLUSH TO PREVENT A HANG.
    971   1.1       cgd 	 * ttywflush(tp) will hang if there are characters in the outq.
    972   1.1       cgd 	 */
    973   1.1       cgd 	if (cmd == TIOCEXT) {
    974   1.1       cgd 		/*
    975   1.1       cgd 		 * When the EXTPROC bit is being toggled, we need
    976   1.1       cgd 		 * to send an TIOCPKT_IOCTL if the packet driver
    977   1.1       cgd 		 * is turned on.
    978   1.1       cgd 		 */
    979   1.1       cgd 		if (*(int *)data) {
    980   1.1       cgd 			if (pti->pt_flags & PF_PKT) {
    981   1.1       cgd 				pti->pt_send |= TIOCPKT_IOCTL;
    982   1.1       cgd 				ptcwakeup(tp, FREAD);
    983   1.1       cgd 			}
    984  1.37   mycroft 			SET(tp->t_lflag, EXTPROC);
    985   1.1       cgd 		} else {
    986  1.39      fvdl 			if (ISSET(tp->t_lflag, EXTPROC) &&
    987   1.1       cgd 			    (pti->pt_flags & PF_PKT)) {
    988   1.1       cgd 				pti->pt_send |= TIOCPKT_IOCTL;
    989   1.1       cgd 				ptcwakeup(tp, FREAD);
    990   1.1       cgd 			}
    991  1.37   mycroft 			CLR(tp->t_lflag, EXTPROC);
    992   1.1       cgd 		}
    993   1.1       cgd 		return(0);
    994  1.71       dsl 	}
    995  1.71       dsl 
    996  1.63   gehenna 	if (cdev != NULL && cdev->d_open == ptcopen)
    997   1.1       cgd 		switch (cmd) {
    998   1.1       cgd 
    999   1.1       cgd 		case TIOCGPGRP:
   1000  1.35        pk 			/*
   1001  1.35        pk 			 * We avoid calling ttioctl on the controller since,
   1002   1.1       cgd 			 * in that case, tp must be the controlling terminal.
   1003   1.1       cgd 			 */
   1004   1.1       cgd 			*(int *)data = tp->t_pgrp ? tp->t_pgrp->pg_id : 0;
   1005   1.1       cgd 			return (0);
   1006   1.1       cgd 
   1007   1.1       cgd 		case TIOCPKT:
   1008   1.1       cgd 			if (*(int *)data) {
   1009   1.1       cgd 				if (pti->pt_flags & PF_UCNTL)
   1010   1.1       cgd 					return (EINVAL);
   1011   1.1       cgd 				pti->pt_flags |= PF_PKT;
   1012   1.1       cgd 			} else
   1013   1.1       cgd 				pti->pt_flags &= ~PF_PKT;
   1014   1.1       cgd 			return (0);
   1015   1.1       cgd 
   1016   1.1       cgd 		case TIOCUCNTL:
   1017   1.1       cgd 			if (*(int *)data) {
   1018   1.1       cgd 				if (pti->pt_flags & PF_PKT)
   1019   1.1       cgd 					return (EINVAL);
   1020   1.1       cgd 				pti->pt_flags |= PF_UCNTL;
   1021   1.1       cgd 			} else
   1022   1.1       cgd 				pti->pt_flags &= ~PF_UCNTL;
   1023   1.1       cgd 			return (0);
   1024   1.1       cgd 
   1025   1.1       cgd 		case TIOCREMOTE:
   1026   1.1       cgd 			if (*(int *)data)
   1027   1.1       cgd 				pti->pt_flags |= PF_REMOTE;
   1028   1.1       cgd 			else
   1029   1.1       cgd 				pti->pt_flags &= ~PF_REMOTE;
   1030  1.68        pk 			TTY_LOCK(tp);
   1031   1.1       cgd 			ttyflush(tp, FREAD|FWRITE);
   1032  1.68        pk 			TTY_UNLOCK(tp);
   1033   1.1       cgd 			return (0);
   1034   1.1       cgd 
   1035  1.32  christos #ifdef COMPAT_OLDTTY
   1036  1.35        pk 		case TIOCSETP:
   1037   1.1       cgd 		case TIOCSETN:
   1038   1.2       cgd #endif
   1039   1.1       cgd 		case TIOCSETD:
   1040   1.1       cgd 		case TIOCSETA:
   1041   1.1       cgd 		case TIOCSETAW:
   1042   1.1       cgd 		case TIOCSETAF:
   1043  1.68        pk 			TTY_LOCK(tp);
   1044  1.21       cgd 			ndflush(&tp->t_outq, tp->t_outq.c_cc);
   1045  1.68        pk 			TTY_UNLOCK(tp);
   1046   1.1       cgd 			break;
   1047   1.1       cgd 
   1048   1.1       cgd 		case TIOCSIG:
   1049  1.46       mrg 			sig = (int)(long)*(caddr_t *)data;
   1050  1.44      fvdl 			if (sig <= 0 || sig >= NSIG)
   1051  1.44      fvdl 				return (EINVAL);
   1052  1.68        pk 			TTY_LOCK(tp);
   1053  1.37   mycroft 			if (!ISSET(tp->t_lflag, NOFLSH))
   1054   1.1       cgd 				ttyflush(tp, FREAD|FWRITE);
   1055  1.44      fvdl 			if ((sig == SIGINFO) &&
   1056  1.37   mycroft 			    (!ISSET(tp->t_lflag, NOKERNINFO)))
   1057   1.1       cgd 				ttyinfo(tp);
   1058  1.68        pk 			TTY_UNLOCK(tp);
   1059  1.62     itohy 			pgsignal(tp->t_pgrp, sig, 1);
   1060   1.1       cgd 			return(0);
   1061   1.1       cgd 		}
   1062  1.71       dsl 
   1063  1.70      fvdl 	error = (*tp->t_linesw->l_ioctl)(tp, cmd, data, flag, p);
   1064  1.61    atatat 	if (error == EPASSTHROUGH)
   1065  1.70      fvdl 		 error = ttioctl(tp, cmd, data, flag, p);
   1066  1.61    atatat 	if (error == EPASSTHROUGH) {
   1067   1.1       cgd 		if (pti->pt_flags & PF_UCNTL &&
   1068   1.1       cgd 		    (cmd & ~0xff) == UIOCCMD(0)) {
   1069   1.1       cgd 			if (cmd & 0xff) {
   1070   1.1       cgd 				pti->pt_ucntl = (u_char)cmd;
   1071   1.1       cgd 				ptcwakeup(tp, FREAD);
   1072   1.1       cgd 			}
   1073   1.1       cgd 			return (0);
   1074   1.1       cgd 		}
   1075   1.1       cgd 	}
   1076   1.1       cgd 	/*
   1077   1.1       cgd 	 * If external processing and packet mode send ioctl packet.
   1078   1.1       cgd 	 */
   1079  1.37   mycroft 	if (ISSET(tp->t_lflag, EXTPROC) && (pti->pt_flags & PF_PKT)) {
   1080   1.1       cgd 		switch(cmd) {
   1081   1.1       cgd 		case TIOCSETA:
   1082   1.1       cgd 		case TIOCSETAW:
   1083   1.1       cgd 		case TIOCSETAF:
   1084  1.32  christos #ifdef COMPAT_OLDTTY
   1085   1.1       cgd 		case TIOCSETP:
   1086   1.1       cgd 		case TIOCSETN:
   1087   1.1       cgd 		case TIOCSETC:
   1088   1.1       cgd 		case TIOCSLTC:
   1089   1.1       cgd 		case TIOCLBIS:
   1090   1.1       cgd 		case TIOCLBIC:
   1091   1.1       cgd 		case TIOCLSET:
   1092   1.1       cgd #endif
   1093   1.1       cgd 			pti->pt_send |= TIOCPKT_IOCTL;
   1094  1.22       cgd 			ptcwakeup(tp, FREAD);
   1095   1.1       cgd 		default:
   1096   1.1       cgd 			break;
   1097   1.1       cgd 		}
   1098   1.1       cgd 	}
   1099  1.37   mycroft 	stop = ISSET(tp->t_iflag, IXON) && CCEQ(cc[VSTOP], CTRL('s'))
   1100   1.1       cgd 		&& CCEQ(cc[VSTART], CTRL('q'));
   1101   1.1       cgd 	if (pti->pt_flags & PF_NOSTOP) {
   1102   1.1       cgd 		if (stop) {
   1103   1.1       cgd 			pti->pt_send &= ~TIOCPKT_NOSTOP;
   1104   1.1       cgd 			pti->pt_send |= TIOCPKT_DOSTOP;
   1105   1.1       cgd 			pti->pt_flags &= ~PF_NOSTOP;
   1106   1.1       cgd 			ptcwakeup(tp, FREAD);
   1107   1.1       cgd 		}
   1108   1.1       cgd 	} else {
   1109   1.1       cgd 		if (!stop) {
   1110   1.1       cgd 			pti->pt_send &= ~TIOCPKT_DOSTOP;
   1111   1.1       cgd 			pti->pt_send |= TIOCPKT_NOSTOP;
   1112   1.1       cgd 			pti->pt_flags |= PF_NOSTOP;
   1113   1.1       cgd 			ptcwakeup(tp, FREAD);
   1114   1.1       cgd 		}
   1115   1.1       cgd 	}
   1116   1.1       cgd 	return (error);
   1117   1.1       cgd }
   1118