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freebsd-dev/sys/kern/tty.c
Ed Schouten dacf7de1a6 Don't forget to initialize `int error' in ttydev_open(). 
I've had some reports in the past that opening an already opened TTY
through, for example, /dev/tty can fail with random error codes. Looking
at ttydev_open(), I can see there is a way `error' is returned without
initialising it. Even though I haven't had any confirmation this fixes
the bug, I'll fix it anyway.

Reported by:	Andrzej Tobola <ato iem pw edu pl>
2008-09-26 18:17:04 +00:00

1819 lines
39 KiB
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/*-
* Copyright (c) 2008 Ed Schouten <ed@FreeBSD.org>
* All rights reserved.
*
* Portions of this software were developed under sponsorship from Snow
* B.V., the Netherlands.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_compat.h"
#include <sys/param.h>
#include <sys/conf.h>
#include <sys/cons.h>
#include <sys/fcntl.h>
#include <sys/file.h>
#include <sys/filio.h>
#ifdef COMPAT_43TTY
#include <sys/ioctl_compat.h>
#endif /* COMPAT_43TTY */
#include <sys/kernel.h>
#include <sys/limits.h>
#include <sys/malloc.h>
#include <sys/mount.h>
#include <sys/poll.h>
#include <sys/priv.h>
#include <sys/proc.h>
#include <sys/serial.h>
#include <sys/signal.h>
#include <sys/stat.h>
#include <sys/sx.h>
#include <sys/sysctl.h>
#include <sys/systm.h>
#include <sys/tty.h>
#include <sys/ttycom.h>
#define TTYDEFCHARS
#include <sys/ttydefaults.h>
#undef TTYDEFCHARS
#include <sys/ucred.h>
#include <sys/vnode.h>
#include <machine/stdarg.h>
static MALLOC_DEFINE(M_TTY, "tty", "tty device");
static void tty_rel_free(struct tty *tp);
static TAILQ_HEAD(, tty) tty_list = TAILQ_HEAD_INITIALIZER(tty_list);
static struct sx tty_list_sx;
SX_SYSINIT(tty_list, &tty_list_sx, "tty list");
static unsigned int tty_list_count = 0;
/*
* Flags that are supported and stored by this implementation.
*/
#define TTYSUP_IFLAG (IGNBRK|BRKINT|IGNPAR|PARMRK|INPCK|ISTRIP|\
INLCR|IGNCR|ICRNL|IXON|IXOFF|IXANY|IMAXBEL)
#define TTYSUP_OFLAG (OPOST|ONLCR|TAB3|ONOEOT|OCRNL|ONOCR|ONLRET)
#define TTYSUP_LFLAG (ECHOKE|ECHOE|ECHOK|ECHO|ECHONL|ECHOPRT|\
ECHOCTL|ISIG|ICANON|ALTWERASE|IEXTEN|TOSTOP|\
FLUSHO|NOKERNINFO|NOFLSH)
#define TTYSUP_CFLAG (CIGNORE|CSIZE|CSTOPB|CREAD|PARENB|PARODD|\
HUPCL|CLOCAL|CCTS_OFLOW|CRTS_IFLOW|CDTR_IFLOW|\
CDSR_OFLOW|CCAR_OFLOW)
#define TTY_CALLOUT(tp,d) ((tp)->t_dev != (d))
/*
* Set TTY buffer sizes.
*/
static void
tty_watermarks(struct tty *tp)
{
speed_t sp;
/* Provide an input buffer for 0.2 seconds of data. */
sp = MAX(tp->t_termios.c_ispeed, 0);
ttyinq_setsize(&tp->t_inq, tp, sp / 5);
/* Set low watermark at 10% (when 90% is available). */
tp->t_inlow = (ttyinq_getsize(&tp->t_inq) * 9) / 10;
/* Provide an ouput buffer for 0.2 seconds of data. */
sp = MAX(tp->t_termios.c_ospeed, 0);
ttyoutq_setsize(&tp->t_outq, tp, sp / 5);
/* Set low watermark at 10% (when 90% is available). */
tp->t_outlow = (ttyoutq_getsize(&tp->t_outq) * 9) / 10;
}
static int
tty_drain(struct tty *tp)
{
int error;
while (ttyoutq_bytesused(&tp->t_outq) > 0) {
ttydevsw_outwakeup(tp);
/* Could be handled synchronously. */
if (ttyoutq_bytesused(&tp->t_outq) == 0)
return (0);
/* Wait for data to be drained. */
error = tty_wait(tp, &tp->t_outwait);
if (error)
return (error);
}
return (0);
}
/*
* Because the revoke() call already calls d_close() without making sure
* all threads are purged from the TTY, we can only destroy the buffers
* and such when the last thread leaves the TTY. ttydev_enter() and
* ttydev_leave() are called from within the cdev functions, to make
* sure we can garbage collect the TTY.
*/
static __inline int
ttydev_enter(struct tty *tp)
{
tty_lock(tp);
if (tty_gone(tp) || !tty_opened(tp)) {
/* Device is already gone. */
tty_unlock(tp);
return (ENXIO);
}
return (0);
}
static void
ttydev_leave(struct tty *tp)
{
tty_lock_assert(tp, MA_OWNED);
if (tty_opened(tp) || tp->t_flags & TF_OPENCLOSE) {
/* Device is still opened somewhere. */
tty_unlock(tp);
return;
}
tp->t_flags |= TF_OPENCLOSE;
/* Stop asynchronous I/O. */
funsetown(&tp->t_sigio);
/* Remove console TTY. */
if (constty == tp)
constty_clear();
/* Drain any output. */
MPASS((tp->t_flags & TF_STOPPED) == 0);
if (!tty_gone(tp))
tty_drain(tp);
ttydisc_close(tp);
/* Destroy associated buffers already. */
ttyinq_free(&tp->t_inq);
tp->t_inlow = 0;
ttyoutq_free(&tp->t_outq);
tp->t_outlow = 0;
knlist_clear(&tp->t_inpoll.si_note, 1);
knlist_clear(&tp->t_outpoll.si_note, 1);
if (!tty_gone(tp))
ttydevsw_close(tp);
tp->t_flags &= ~TF_OPENCLOSE;
tty_rel_free(tp);
}
/*
* Operations that are exposed through the character device in /dev.
*/
static int
ttydev_open(struct cdev *dev, int oflags, int devtype, struct thread *td)
{
struct tty *tp = dev->si_drv1;
int error = 0;
/* Disallow access when the TTY belongs to a different prison. */
if (dev->si_cred != NULL &&
dev->si_cred->cr_prison != td->td_ucred->cr_prison &&
priv_check(td, PRIV_TTY_PRISON)) {
return (EPERM);
}
tty_lock(tp);
if (tty_gone(tp)) {
/* Device is already gone. */
tty_unlock(tp);
return (ENXIO);
}
/*
* Prevent the TTY from being opened when being torn down or
* built up by unrelated processes.
*/
if (tp->t_flags & TF_OPENCLOSE) {
tty_unlock(tp);
return (EBUSY);
}
tp->t_flags |= TF_OPENCLOSE;
/*
* Make sure the "tty" and "cua" device cannot be opened at the
* same time.
*/
if (TTY_CALLOUT(tp, dev)) {
if (tp->t_flags & TF_OPENED_IN) {
error = EBUSY;
goto done;
}
} else {
if (tp->t_flags & TF_OPENED_OUT) {
error = EBUSY;
goto done;
}
}
if (tp->t_flags & TF_EXCLUDE && priv_check(td, PRIV_TTY_EXCLUSIVE)) {
error = EBUSY;
goto done;
}
if (!tty_opened(tp)) {
/* Set proper termios flags. */
if (TTY_CALLOUT(tp, dev)) {
tp->t_termios = tp->t_termios_init_out;
} else {
tp->t_termios = tp->t_termios_init_in;
}
ttydevsw_param(tp, &tp->t_termios);
ttydevsw_modem(tp, SER_DTR|SER_RTS, 0);
error = ttydevsw_open(tp);
if (error != 0)
goto done;
ttydisc_open(tp);
tty_watermarks(tp);
}
/* Wait for Carrier Detect. */
if (!TTY_CALLOUT(tp, dev) && (oflags & O_NONBLOCK) == 0 &&
(tp->t_termios.c_cflag & CLOCAL) == 0) {
while ((ttydevsw_modem(tp, 0, 0) & SER_DCD) == 0) {
error = tty_wait(tp, &tp->t_dcdwait);
if (error != 0)
goto done;
}
}
if (TTY_CALLOUT(tp, dev)) {
tp->t_flags |= TF_OPENED_OUT;
} else {
tp->t_flags |= TF_OPENED_IN;
}
done: tp->t_flags &= ~TF_OPENCLOSE;
ttydev_leave(tp);
return (error);
}
static int
ttydev_close(struct cdev *dev, int fflag, int devtype, struct thread *td)
{
struct tty *tp = dev->si_drv1;
tty_lock(tp);
/*
* This can only be called once. The callin and the callout
* devices cannot be opened at the same time.
*/
MPASS((tp->t_flags & TF_OPENED) != TF_OPENED);
tp->t_flags &= ~(TF_OPENED|TF_EXCLUDE|TF_STOPPED);
/* Properly wake up threads that are stuck - revoke(). */
tp->t_revokecnt++;
tty_wakeup(tp, FREAD|FWRITE);
cv_broadcast(&tp->t_bgwait);
ttydev_leave(tp);
return (0);
}
static __inline int
tty_is_ctty(struct tty *tp, struct proc *p)
{
tty_lock_assert(tp, MA_OWNED);
return (p->p_session == tp->t_session && p->p_flag & P_CONTROLT);
}
static int
tty_wait_background(struct tty *tp, struct thread *td, int sig)
{
struct proc *p = td->td_proc;
struct pgrp *pg;
int error;
MPASS(sig == SIGTTIN || sig == SIGTTOU);
tty_lock_assert(tp, MA_OWNED);
for (;;) {
PROC_LOCK(p);
/*
* The process should only sleep, when:
* - This terminal is the controling terminal
* - Its process group is not the foreground process
* group
* - The parent process isn't waiting for the child to
* exit
* - the signal to send to the process isn't masked
*/
if (!tty_is_ctty(tp, p) ||
p->p_pgrp == tp->t_pgrp || p->p_flag & P_PPWAIT ||
SIGISMEMBER(p->p_sigacts->ps_sigignore, sig) ||
SIGISMEMBER(td->td_sigmask, sig)) {
/* Allow the action to happen. */
PROC_UNLOCK(p);
return (0);
}
/*
* Send the signal and sleep until we're the new
* foreground process group.
*/
pg = p->p_pgrp;
PROC_UNLOCK(p);
if (pg->pg_jobc == 0)
return (EIO);
PGRP_LOCK(pg);
pgsignal(pg, sig, 1);
PGRP_UNLOCK(pg);
error = tty_wait(tp, &tp->t_bgwait);
if (error)
return (error);
}
}
static int
ttydev_read(struct cdev *dev, struct uio *uio, int ioflag)
{
struct tty *tp = dev->si_drv1;
int error;
error = ttydev_enter(tp);
if (error)
return (0);
error = tty_wait_background(tp, curthread, SIGTTIN);
if (error)
goto done;
error = ttydisc_read(tp, uio, ioflag);
done: ttydev_leave(tp);
/*
* The read() and write() calls should not throw an error when
* the device is ripped offline.
*/
if (error == ENXIO)
return (0);
return (error);
}
static int
ttydev_write(struct cdev *dev, struct uio *uio, int ioflag)
{
struct tty *tp = dev->si_drv1;
int error;
error = ttydev_enter(tp);
if (error)
return (0);
if (tp->t_termios.c_lflag & TOSTOP) {
error = tty_wait_background(tp, curthread, SIGTTOU);
if (error)
goto done;
}
error = ttydisc_write(tp, uio, ioflag);
done: ttydev_leave(tp);
/*
* The read() and write() calls should not throw an error when
* the device is ripped offline.
*/
if (error == ENXIO)
return (0);
return (error);
}
static int
ttydev_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag,
struct thread *td)
{
struct tty *tp = dev->si_drv1;
int error;
error = ttydev_enter(tp);
if (error)
return (error);
switch (cmd) {
case TIOCCBRK:
case TIOCCONS:
case TIOCDRAIN:
case TIOCEXCL:
case TIOCFLUSH:
case TIOCNXCL:
case TIOCSBRK:
case TIOCSCTTY:
case TIOCSETA:
case TIOCSETAF:
case TIOCSETAW:
case TIOCSPGRP:
case TIOCSTART:
case TIOCSTAT:
case TIOCSTOP:
case TIOCSWINSZ:
#if 0
case TIOCSDRAINWAIT:
case TIOCSETD:
case TIOCSTI:
#endif
#ifdef COMPAT_43TTY
case TIOCLBIC:
case TIOCLBIS:
case TIOCLSET:
case TIOCSETC:
case OTIOCSETD:
case TIOCSETN:
case TIOCSETP:
case TIOCSLTC:
#endif /* COMPAT_43TTY */
/*
* If the ioctl() causes the TTY to be modified, let it
* wait in the background.
*/
error = tty_wait_background(tp, curthread, SIGTTOU);
if (error)
goto done;
}
error = tty_ioctl(tp, cmd, data, td);
done: ttydev_leave(tp);
return (error);
}
static int
ttydev_poll(struct cdev *dev, int events, struct thread *td)
{
struct tty *tp = dev->si_drv1;
int error, revents = 0;
error = ttydev_enter(tp);
if (error) {
/* Don't return the error here, but the event mask. */
return (events &
(POLLHUP|POLLIN|POLLRDNORM|POLLOUT|POLLWRNORM));
}
if (events & (POLLIN|POLLRDNORM)) {
/* See if we can read something. */
if (ttydisc_read_poll(tp) > 0)
revents |= events & (POLLIN|POLLRDNORM);
}
if (events & (POLLOUT|POLLWRNORM)) {
/* See if we can write something. */
if (ttydisc_write_poll(tp) > 0)
revents |= events & (POLLOUT|POLLWRNORM);
}
if (tp->t_flags & TF_ZOMBIE)
/* Hangup flag on zombie state. */
revents |= events & POLLHUP;
if (revents == 0) {
if (events & (POLLIN|POLLRDNORM))
selrecord(td, &tp->t_inpoll);
if (events & (POLLOUT|POLLWRNORM))
selrecord(td, &tp->t_outpoll);
}
ttydev_leave(tp);
return (revents);
}
static int
ttydev_mmap(struct cdev *dev, vm_offset_t offset, vm_paddr_t *paddr, int nprot)
{
struct tty *tp = dev->si_drv1;
int error;
/* Handle mmap() through the driver. */
error = ttydev_enter(tp);
if (error)
return (-1);
error = ttydevsw_mmap(tp, offset, paddr, nprot);
ttydev_leave(tp);
return (error);
}
/*
* kqueue support.
*/
static void
tty_kqops_read_detach(struct knote *kn)
{
struct tty *tp = kn->kn_hook;
knlist_remove(&tp->t_inpoll.si_note, kn, 0);
}
static int
tty_kqops_read_event(struct knote *kn, long hint)
{
struct tty *tp = kn->kn_hook;
tty_lock_assert(tp, MA_OWNED);
if (tty_gone(tp) || tp->t_flags & TF_ZOMBIE) {
kn->kn_flags |= EV_EOF;
return (1);
} else {
kn->kn_data = ttydisc_read_poll(tp);
return (kn->kn_data > 0);
}
}
static void
tty_kqops_write_detach(struct knote *kn)
{
struct tty *tp = kn->kn_hook;
knlist_remove(&tp->t_outpoll.si_note, kn, 0);
}
static int
tty_kqops_write_event(struct knote *kn, long hint)
{
struct tty *tp = kn->kn_hook;
tty_lock_assert(tp, MA_OWNED);
if (tty_gone(tp)) {
kn->kn_flags |= EV_EOF;
return (1);
} else {
kn->kn_data = ttydisc_write_poll(tp);
return (kn->kn_data > 0);
}
}
static struct filterops tty_kqops_read =
{ 1, NULL, tty_kqops_read_detach, tty_kqops_read_event };
static struct filterops tty_kqops_write =
{ 1, NULL, tty_kqops_write_detach, tty_kqops_write_event };
static int
ttydev_kqfilter(struct cdev *dev, struct knote *kn)
{
struct tty *tp = dev->si_drv1;
int error;
error = ttydev_enter(tp);
if (error)
return (error);
switch (kn->kn_filter) {
case EVFILT_READ:
kn->kn_hook = tp;
kn->kn_fop = &tty_kqops_read;
knlist_add(&tp->t_inpoll.si_note, kn, 1);
break;
case EVFILT_WRITE:
kn->kn_hook = tp;
kn->kn_fop = &tty_kqops_write;
knlist_add(&tp->t_outpoll.si_note, kn, 1);
break;
default:
error = EINVAL;
break;
}
ttydev_leave(tp);
return (error);
}
static struct cdevsw ttydev_cdevsw = {
.d_version = D_VERSION,
.d_open = ttydev_open,
.d_close = ttydev_close,
.d_read = ttydev_read,
.d_write = ttydev_write,
.d_ioctl = ttydev_ioctl,
.d_kqfilter = ttydev_kqfilter,
.d_poll = ttydev_poll,
.d_mmap = ttydev_mmap,
.d_name = "ttydev",
.d_flags = D_TTY,
};
/*
* Init/lock-state devices
*/
static int
ttyil_open(struct cdev *dev, int oflags, int devtype, struct thread *td)
{
struct tty *tp = dev->si_drv1;
int error = 0;
tty_lock(tp);
if (tty_gone(tp))
error = ENODEV;
tty_unlock(tp);
return (error);
}
static int
ttyil_close(struct cdev *dev, int flag, int mode, struct thread *td)
{
return (0);
}
static int
ttyil_rdwr(struct cdev *dev, struct uio *uio, int ioflag)
{
return (ENODEV);
}
static int
ttyil_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag,
struct thread *td)
{
struct tty *tp = dev->si_drv1;
int error = 0;
tty_lock(tp);
if (tty_gone(tp)) {
error = ENODEV;
goto done;
}
switch (cmd) {
case TIOCGETA:
/* Obtain terminal flags through tcgetattr(). */
bcopy(dev->si_drv2, data, sizeof(struct termios));
break;
case TIOCSETA:
/* Set terminal flags through tcsetattr(). */
error = priv_check(td, PRIV_TTY_SETA);
if (error)
break;
bcopy(data, dev->si_drv2, sizeof(struct termios));
break;
case TIOCGETD:
*(int *)data = TTYDISC;
break;
case TIOCGWINSZ:
bzero(data, sizeof(struct winsize));
break;
default:
error = ENOTTY;
}
done: tty_unlock(tp);
return (error);
}
static struct cdevsw ttyil_cdevsw = {
.d_version = D_VERSION,
.d_open = ttyil_open,
.d_close = ttyil_close,
.d_read = ttyil_rdwr,
.d_write = ttyil_rdwr,
.d_ioctl = ttyil_ioctl,
.d_name = "ttyil",
.d_flags = D_TTY,
};
static void
tty_init_termios(struct tty *tp)
{
struct termios *t = &tp->t_termios_init_in;
t->c_cflag = TTYDEF_CFLAG;
t->c_iflag = TTYDEF_IFLAG;
t->c_lflag = TTYDEF_LFLAG;
t->c_oflag = TTYDEF_OFLAG;
t->c_ispeed = TTYDEF_SPEED;
t->c_ospeed = TTYDEF_SPEED;
bcopy(ttydefchars, &t->c_cc, sizeof ttydefchars);
tp->t_termios_init_out = *t;
}
void
tty_init_console(struct tty *tp, speed_t s)
{
struct termios *ti = &tp->t_termios_init_in;
struct termios *to = &tp->t_termios_init_out;
if (s != 0) {
ti->c_ispeed = ti->c_ospeed = s;
to->c_ispeed = to->c_ospeed = s;
}
ti->c_cflag |= CLOCAL;
to->c_cflag |= CLOCAL;
}
/*
* Standard device routine implementations, mostly meant for
* pseudo-terminal device drivers. When a driver creates a new terminal
* device class, missing routines are patched.
*/
static int
ttydevsw_defopen(struct tty *tp)
{
return (0);
}
static void
ttydevsw_defclose(struct tty *tp)
{
}
static void
ttydevsw_defoutwakeup(struct tty *tp)
{
panic("Terminal device has output, while not implemented");
}
static void
ttydevsw_definwakeup(struct tty *tp)
{
}
static int
ttydevsw_defioctl(struct tty *tp, u_long cmd, caddr_t data, struct thread *td)
{
return (ENOIOCTL);
}
static int
ttydevsw_defparam(struct tty *tp, struct termios *t)
{
/* Use a fake baud rate, we're not a real device. */
t->c_ispeed = t->c_ospeed = TTYDEF_SPEED_PSEUDO;
return (0);
}
static int
ttydevsw_defmodem(struct tty *tp, int sigon, int sigoff)
{
/* Simulate a carrier to make the TTY layer happy. */
return (SER_DCD);
}
static int
ttydevsw_defmmap(struct tty *tp, vm_offset_t offset, vm_paddr_t *paddr,
int nprot)
{
return (-1);
}
static void
ttydevsw_defpktnotify(struct tty *tp, char event)
{
}
static void
ttydevsw_deffree(void *softc)
{
panic("Terminal device freed without a free-handler");
}
/*
* TTY allocation and deallocation. TTY devices can be deallocated when
* the driver doesn't use it anymore, when the TTY isn't a session's
* controlling TTY and when the device node isn't opened through devfs.
*/
struct tty *
tty_alloc(struct ttydevsw *tsw, void *sc, struct mtx *mutex)
{
struct tty *tp;
/* Make sure the driver defines all routines. */
#define PATCH_FUNC(x) do { \
if (tsw->tsw_ ## x == NULL) \
tsw->tsw_ ## x = ttydevsw_def ## x; \
} while (0)
PATCH_FUNC(open);
PATCH_FUNC(close);
PATCH_FUNC(outwakeup);
PATCH_FUNC(inwakeup);
PATCH_FUNC(ioctl);
PATCH_FUNC(param);
PATCH_FUNC(modem);
PATCH_FUNC(mmap);
PATCH_FUNC(pktnotify);
PATCH_FUNC(free);
#undef PATCH_FUNC
tp = malloc(sizeof(struct tty), M_TTY, M_WAITOK|M_ZERO);
tp->t_devsw = tsw;
tp->t_devswsoftc = sc;
tp->t_flags = tsw->tsw_flags;
tty_init_termios(tp);
cv_init(&tp->t_inwait, "tty input");
cv_init(&tp->t_outwait, "tty output");
cv_init(&tp->t_bgwait, "tty background");
cv_init(&tp->t_dcdwait, "tty dcd");
ttyinq_init(&tp->t_inq);
ttyoutq_init(&tp->t_outq);
/* Allow drivers to use a custom mutex to lock the TTY. */
if (mutex != NULL) {
tp->t_mtx = mutex;
} else {
tp->t_mtx = &tp->t_mtxobj;
mtx_init(&tp->t_mtxobj, "tty lock", NULL, MTX_DEF);
}
knlist_init(&tp->t_inpoll.si_note, tp->t_mtx, NULL, NULL, NULL);
knlist_init(&tp->t_outpoll.si_note, tp->t_mtx, NULL, NULL, NULL);
sx_xlock(&tty_list_sx);
TAILQ_INSERT_TAIL(&tty_list, tp, t_list);
tty_list_count++;
sx_xunlock(&tty_list_sx);
return (tp);
}
static void
tty_dealloc(void *arg)
{
struct tty *tp = arg;
sx_xlock(&tty_list_sx);
TAILQ_REMOVE(&tty_list, tp, t_list);
tty_list_count--;
sx_xunlock(&tty_list_sx);
/* Make sure we haven't leaked buffers. */
MPASS(ttyinq_getsize(&tp->t_inq) == 0);
MPASS(ttyoutq_getsize(&tp->t_outq) == 0);
knlist_destroy(&tp->t_inpoll.si_note);
knlist_destroy(&tp->t_outpoll.si_note);
cv_destroy(&tp->t_inwait);
cv_destroy(&tp->t_outwait);
cv_destroy(&tp->t_bgwait);
cv_destroy(&tp->t_dcdwait);
if (tp->t_mtx == &tp->t_mtxobj)
mtx_destroy(&tp->t_mtxobj);
ttydevsw_free(tp);
free(tp, M_TTY);
}
static void
tty_rel_free(struct tty *tp)
{
struct cdev *dev;
tty_lock_assert(tp, MA_OWNED);
#define TF_ACTIVITY (TF_GONE|TF_OPENED|TF_HOOK|TF_OPENCLOSE)
if (tp->t_sessioncnt != 0 || (tp->t_flags & TF_ACTIVITY) != TF_GONE) {
/* TTY is still in use. */
tty_unlock(tp);
return;
}
/* TTY can be deallocated. */
dev = tp->t_dev;
tp->t_dev = NULL;
tty_unlock(tp);
destroy_dev_sched_cb(dev, tty_dealloc, tp);
}
void
tty_rel_pgrp(struct tty *tp, struct pgrp *pg)
{
MPASS(tp->t_sessioncnt > 0);
tty_lock_assert(tp, MA_OWNED);
if (tp->t_pgrp == pg)
tp->t_pgrp = NULL;
tty_unlock(tp);
}
void
tty_rel_sess(struct tty *tp, struct session *sess)
{
MPASS(tp->t_sessioncnt > 0);
/* Current session has left. */
if (tp->t_session == sess) {
tp->t_session = NULL;
MPASS(tp->t_pgrp == NULL);
}
tp->t_sessioncnt--;
tty_rel_free(tp);
}
void
tty_rel_gone(struct tty *tp)
{
MPASS(!tty_gone(tp));
/* Simulate carrier removal. */
ttydisc_modem(tp, 0);
/* Wake up misc. blocked threads. */
cv_broadcast(&tp->t_bgwait);
cv_broadcast(&tp->t_dcdwait);
tp->t_flags |= TF_GONE;
tty_rel_free(tp);
}
/*
* Exposing information about current TTY's through sysctl
*/
static void
tty_to_xtty(struct tty *tp, struct xtty *xt)
{
tty_lock_assert(tp, MA_OWNED);
xt->xt_size = sizeof(struct xtty);
xt->xt_insize = ttyinq_getsize(&tp->t_inq);
xt->xt_incc = ttyinq_bytescanonicalized(&tp->t_inq);
xt->xt_inlc = ttyinq_bytesline(&tp->t_inq);
xt->xt_inlow = tp->t_inlow;
xt->xt_outsize = ttyoutq_getsize(&tp->t_outq);
xt->xt_outcc = ttyoutq_bytesused(&tp->t_outq);
xt->xt_outlow = tp->t_outlow;
xt->xt_column = tp->t_column;
xt->xt_pgid = tp->t_pgrp ? tp->t_pgrp->pg_id : 0;
xt->xt_sid = tp->t_session ? tp->t_session->s_sid : 0;
xt->xt_flags = tp->t_flags;
xt->xt_dev = tp->t_dev ? dev2udev(tp->t_dev) : NODEV;
}
static int
sysctl_kern_ttys(SYSCTL_HANDLER_ARGS)
{
unsigned long lsize;
struct xtty *xtlist, *xt;
struct tty *tp;
int error;
sx_slock(&tty_list_sx);
lsize = tty_list_count * sizeof(struct xtty);
if (lsize == 0) {
sx_sunlock(&tty_list_sx);
return (0);
}
xtlist = xt = malloc(lsize, M_TEMP, M_WAITOK);
TAILQ_FOREACH(tp, &tty_list, t_list) {
tty_lock(tp);
tty_to_xtty(tp, xt);
tty_unlock(tp);
xt++;
}
sx_sunlock(&tty_list_sx);
error = SYSCTL_OUT(req, xtlist, lsize);
free(xtlist, M_TEMP);
return (error);
}
SYSCTL_PROC(_kern, OID_AUTO, ttys, CTLTYPE_OPAQUE|CTLFLAG_RD,
0, 0, sysctl_kern_ttys, "S,xtty", "List of TTYs");
/*
* Device node creation. Device has been set up, now we can expose it to
* the user.
*/
void
tty_makedev(struct tty *tp, struct ucred *cred, const char *fmt, ...)
{
va_list ap;
struct cdev *dev;
const char *prefix = "tty";
char name[SPECNAMELEN - 3]; /* for "tty" and "cua". */
uid_t uid;
gid_t gid;
mode_t mode;
/* Remove "tty" prefix from devices like PTY's. */
if (tp->t_flags & TF_NOPREFIX)
prefix = "";
va_start(ap, fmt);
vsnrprintf(name, sizeof name, 32, fmt, ap);
va_end(ap);
if (cred == NULL) {
/* System device. */
uid = UID_ROOT;
gid = GID_WHEEL;
mode = S_IRUSR|S_IWUSR;
} else {
/* User device. */
uid = cred->cr_ruid;
gid = GID_TTY;
mode = S_IRUSR|S_IWUSR|S_IWGRP;
}
/* Master call-in device. */
dev = make_dev_cred(&ttydev_cdevsw, 0, cred,
uid, gid, mode, "%s%s", prefix, name);
dev->si_drv1 = tp;
tp->t_dev = dev;
/* Slave call-in devices. */
if (tp->t_flags & TF_INITLOCK) {
dev = make_dev_cred(&ttyil_cdevsw, 0, cred,
uid, gid, mode, "%s%s.init", prefix, name);
dev_depends(tp->t_dev, dev);
dev->si_drv1 = tp;
dev->si_drv2 = &tp->t_termios_init_in;
dev = make_dev_cred(&ttyil_cdevsw, 0, cred,
uid, gid, mode, "%s%s.lock", prefix, name);
dev_depends(tp->t_dev, dev);
dev->si_drv1 = tp;
dev->si_drv2 = &tp->t_termios_lock_in;
}
/* Call-out devices. */
if (tp->t_flags & TF_CALLOUT) {
dev = make_dev_cred(&ttydev_cdevsw, 0, cred,
UID_UUCP, GID_DIALER, 0660, "cua%s", name);
dev_depends(tp->t_dev, dev);
dev->si_drv1 = tp;
/* Slave call-out devices. */
if (tp->t_flags & TF_INITLOCK) {
dev = make_dev_cred(&ttyil_cdevsw, 0, cred,
UID_UUCP, GID_DIALER, 0660, "cua%s.init", name);
dev_depends(tp->t_dev, dev);
dev->si_drv1 = tp;
dev->si_drv2 = &tp->t_termios_init_out;
dev = make_dev_cred(&ttyil_cdevsw, 0, cred,
UID_UUCP, GID_DIALER, 0660, "cua%s.lock", name);
dev_depends(tp->t_dev, dev);
dev->si_drv1 = tp;
dev->si_drv2 = &tp->t_termios_lock_out;
}
}
}
/*
* Signalling processes.
*/
void
tty_signal_sessleader(struct tty *tp, int sig)
{
struct proc *p;
tty_lock_assert(tp, MA_OWNED);
MPASS(sig >= 1 && sig < NSIG);
/* Make signals start output again. */
tp->t_flags &= ~TF_STOPPED;
if (tp->t_session != NULL && tp->t_session->s_leader != NULL) {
p = tp->t_session->s_leader;
PROC_LOCK(p);
psignal(p, sig);
PROC_UNLOCK(p);
}
}
void
tty_signal_pgrp(struct tty *tp, int sig)
{
tty_lock_assert(tp, MA_OWNED);
MPASS(sig >= 1 && sig < NSIG);
/* Make signals start output again. */
tp->t_flags &= ~TF_STOPPED;
if (sig == SIGINFO && !(tp->t_termios.c_lflag & NOKERNINFO))
tty_info(tp);
if (tp->t_pgrp != NULL) {
PGRP_LOCK(tp->t_pgrp);
pgsignal(tp->t_pgrp, sig, 1);
PGRP_UNLOCK(tp->t_pgrp);
}
}
void
tty_wakeup(struct tty *tp, int flags)
{
if (tp->t_flags & TF_ASYNC && tp->t_sigio != NULL)
pgsigio(&tp->t_sigio, SIGIO, (tp->t_session != NULL));
if (flags & FWRITE) {
cv_broadcast(&tp->t_outwait);
selwakeup(&tp->t_outpoll);
KNOTE_LOCKED(&tp->t_outpoll.si_note, 0);
}
if (flags & FREAD) {
cv_broadcast(&tp->t_inwait);
selwakeup(&tp->t_inpoll);
KNOTE_LOCKED(&tp->t_inpoll.si_note, 0);
}
}
int
tty_wait(struct tty *tp, struct cv *cv)
{
int error;
int revokecnt = tp->t_revokecnt;
#if 0
/* XXX: /dev/console also picks up Giant. */
tty_lock_assert(tp, MA_OWNED|MA_NOTRECURSED);
#endif
tty_lock_assert(tp, MA_OWNED);
error = cv_wait_sig(cv, tp->t_mtx);
/* Restart the system call when we may have been revoked. */
if (tp->t_revokecnt != revokecnt)
return (ERESTART);
/* Bail out when the device slipped away. */
if (tty_gone(tp))
return (ENXIO);
return (error);
}
int
tty_timedwait(struct tty *tp, struct cv *cv, int hz)
{
int error;
int revokecnt = tp->t_revokecnt;
#if 0
/* XXX: /dev/console also picks up Giant. */
tty_lock_assert(tp, MA_OWNED|MA_NOTRECURSED);
#endif
tty_lock_assert(tp, MA_OWNED);
error = cv_timedwait_sig(cv, tp->t_mtx, hz);
/* Restart the system call when we may have been revoked. */
if (tp->t_revokecnt != revokecnt)
return (ERESTART);
/* Bail out when the device slipped away. */
if (tty_gone(tp))
return (ENXIO);
return (error);
}
void
tty_flush(struct tty *tp, int flags)
{
if (flags & FWRITE) {
tp->t_flags &= ~TF_HIWAT_OUT;
ttyoutq_flush(&tp->t_outq);
tty_wakeup(tp, FWRITE);
ttydevsw_pktnotify(tp, TIOCPKT_FLUSHWRITE);
}
if (flags & FREAD) {
tty_hiwat_in_unblock(tp);
ttyinq_flush(&tp->t_inq);
ttydevsw_inwakeup(tp);
ttydevsw_pktnotify(tp, TIOCPKT_FLUSHREAD);
}
}
static int
tty_generic_ioctl(struct tty *tp, u_long cmd, void *data, struct thread *td)
{
int error;
switch (cmd) {
/*
* Modem commands.
* The SER_* and TIOCM_* flags are the same, but one bit
* shifted. I don't know why.
*/
case TIOCSDTR:
ttydevsw_modem(tp, SER_DTR, 0);
return (0);
case TIOCCDTR:
ttydevsw_modem(tp, 0, SER_DTR);
return (0);
case TIOCMSET: {
int bits = *(int *)data;
ttydevsw_modem(tp,
(bits & (TIOCM_DTR | TIOCM_RTS)) >> 1,
((~bits) & (TIOCM_DTR | TIOCM_RTS)) >> 1);
return (0);
}
case TIOCMBIS: {
int bits = *(int *)data;
ttydevsw_modem(tp, (bits & (TIOCM_DTR | TIOCM_RTS)) >> 1, 0);
return (0);
}
case TIOCMBIC: {
int bits = *(int *)data;
ttydevsw_modem(tp, 0, (bits & (TIOCM_DTR | TIOCM_RTS)) >> 1);
return (0);
}
case TIOCMGET:
*(int *)data = TIOCM_LE + (ttydevsw_modem(tp, 0, 0) << 1);
return (0);
case FIOASYNC:
if (*(int *)data)
tp->t_flags |= TF_ASYNC;
else
tp->t_flags &= ~TF_ASYNC;
return (0);
case FIONBIO:
/* This device supports non-blocking operation. */
return (0);
case FIONREAD:
*(int *)data = ttyinq_bytescanonicalized(&tp->t_inq);
return (0);
case FIOSETOWN:
if (tp->t_session != NULL && !tty_is_ctty(tp, td->td_proc))
/* Not allowed to set ownership. */
return (ENOTTY);
/* Temporarily unlock the TTY to set ownership. */
tty_unlock(tp);
error = fsetown(*(int *)data, &tp->t_sigio);
tty_lock(tp);
return (error);
case FIOGETOWN:
if (tp->t_session != NULL && !tty_is_ctty(tp, td->td_proc))
/* Not allowed to set ownership. */
return (ENOTTY);
/* Get ownership. */
*(int *)data = fgetown(&tp->t_sigio);
return (0);
case TIOCGETA:
/* Obtain terminal flags through tcgetattr(). */
bcopy(&tp->t_termios, data, sizeof(struct termios));
return (0);
case TIOCSETA:
case TIOCSETAW:
case TIOCSETAF: {
struct termios *t = data;
/*
* Who makes up these funny rules? According to POSIX,
* input baud rate is set equal to the output baud rate
* when zero.
*/
if (t->c_ispeed == 0)
t->c_ispeed = t->c_ospeed;
/* Discard any unsupported bits. */
t->c_iflag &= TTYSUP_IFLAG;
t->c_oflag &= TTYSUP_OFLAG;
t->c_lflag &= TTYSUP_LFLAG;
t->c_cflag &= TTYSUP_CFLAG;
/* Set terminal flags through tcsetattr(). */
if (cmd == TIOCSETAW || cmd == TIOCSETAF) {
error = tty_drain(tp);
if (error)
return (error);
if (cmd == TIOCSETAF)
tty_flush(tp, FREAD);
}
/*
* Only call param() when the flags really change.
*/
if ((t->c_cflag & CIGNORE) == 0 &&
(tp->t_termios.c_cflag != t->c_cflag ||
tp->t_termios.c_ispeed != t->c_ispeed ||
tp->t_termios.c_ospeed != t->c_ospeed)) {
error = ttydevsw_param(tp, t);
if (error)
return (error);
/* XXX: CLOCAL? */
tp->t_termios.c_cflag = t->c_cflag & ~CIGNORE;
tp->t_termios.c_ispeed = t->c_ispeed;
tp->t_termios.c_ospeed = t->c_ospeed;
/* Baud rate has changed - update watermarks. */
tty_watermarks(tp);
}
/* Copy new non-device driver parameters. */
tp->t_termios.c_iflag = t->c_iflag;
tp->t_termios.c_oflag = t->c_oflag;
tp->t_termios.c_lflag = t->c_lflag;
bcopy(t->c_cc, &tp->t_termios.c_cc, sizeof(t->c_cc));
ttydisc_optimize(tp);
if ((t->c_lflag & ICANON) == 0) {
/*
* When in non-canonical mode, wake up all
* readers. Canonicalize any partial input. VMIN
* and VTIME could also be adjusted.
*/
ttyinq_canonicalize(&tp->t_inq);
tty_wakeup(tp, FREAD);
}
/*
* For packet mode: notify the PTY consumer that VSTOP
* and VSTART may have been changed.
*/
if (tp->t_termios.c_iflag & IXON &&
tp->t_termios.c_cc[VSTOP] == CTRL('S') &&
tp->t_termios.c_cc[VSTART] == CTRL('Q'))
ttydevsw_pktnotify(tp, TIOCPKT_DOSTOP);
else
ttydevsw_pktnotify(tp, TIOCPKT_NOSTOP);
return (0);
}
case TIOCGETD:
/* For compatibility - we only support TTYDISC. */
*(int *)data = TTYDISC;
return (0);
case TIOCGPGRP:
if (!tty_is_ctty(tp, td->td_proc))
return (ENOTTY);
if (tp->t_pgrp != NULL)
*(int *)data = tp->t_pgrp->pg_id;
else
*(int *)data = NO_PID;
return (0);
case TIOCGSID:
if (!tty_is_ctty(tp, td->td_proc))
return (ENOTTY);
MPASS(tp->t_session);
*(int *)data = tp->t_session->s_sid;
return (0);
case TIOCSCTTY: {
struct proc *p = td->td_proc;
/* XXX: This looks awful. */
tty_unlock(tp);
sx_xlock(&proctree_lock);
tty_lock(tp);
if (!SESS_LEADER(p)) {
/* Only the session leader may do this. */
sx_xunlock(&proctree_lock);
return (EPERM);
}
if (tp->t_session != NULL && tp->t_session == p->p_session) {
/* This is already our controlling TTY. */
sx_xunlock(&proctree_lock);
return (0);
}
if (!SESS_LEADER(p) || p->p_session->s_ttyvp != NULL ||
(tp->t_session != NULL && tp->t_session->s_ttyvp != NULL)) {
/*
* There is already a relation between a TTY and
* a session, or the caller is not the session
* leader.
*
* Allow the TTY to be stolen when the vnode is
* NULL, but the reference to the TTY is still
* active.
*/
sx_xunlock(&proctree_lock);
return (EPERM);
}
/* Connect the session to the TTY. */
tp->t_session = p->p_session;
tp->t_session->s_ttyp = tp;
tp->t_sessioncnt++;
sx_xunlock(&proctree_lock);
/* Assign foreground process group. */
tp->t_pgrp = p->p_pgrp;
PROC_LOCK(p);
p->p_flag |= P_CONTROLT;
PROC_UNLOCK(p);
return (0);
}
case TIOCSPGRP: {
struct pgrp *pg;
/*
* XXX: Temporarily unlock the TTY to locate the process
* group. This code would be lot nicer if we would ever
* decompose proctree_lock.
*/
tty_unlock(tp);
sx_slock(&proctree_lock);
pg = pgfind(*(int *)data);
if (pg != NULL)
PGRP_UNLOCK(pg);
if (pg == NULL || pg->pg_session != td->td_proc->p_session) {
sx_sunlock(&proctree_lock);
tty_lock(tp);
return (EPERM);
}
tty_lock(tp);
/*
* Determine if this TTY is the controlling TTY after
* relocking the TTY.
*/
if (!tty_is_ctty(tp, td->td_proc)) {
sx_sunlock(&proctree_lock);
return (ENOTTY);
}
tp->t_pgrp = pg;
sx_sunlock(&proctree_lock);
/* Wake up the background process groups. */
cv_broadcast(&tp->t_bgwait);
return (0);
}
case TIOCFLUSH: {
int flags = *(int *)data;
if (flags == 0)
flags = (FREAD|FWRITE);
else
flags &= (FREAD|FWRITE);
tty_flush(tp, flags);
return (0);
}
case TIOCDRAIN:
/* Drain TTY output. */
return tty_drain(tp);
case TIOCCONS:
/* Set terminal as console TTY. */
if (*(int *)data) {
error = priv_check(td, PRIV_TTY_CONSOLE);
if (error)
return (error);
/*
* XXX: constty should really need to be locked!
* XXX: allow disconnected constty's to be stolen!
*/
if (constty == tp)
return (0);
if (constty != NULL)
return (EBUSY);
tty_unlock(tp);
constty_set(tp);
tty_lock(tp);
} else if (constty == tp) {
constty_clear();
}
return (0);
case TIOCGWINSZ:
/* Obtain window size. */
bcopy(&tp->t_winsize, data, sizeof(struct winsize));
return (0);
case TIOCSWINSZ:
/* Set window size. */
if (bcmp(&tp->t_winsize, data, sizeof(struct winsize)) == 0)
return (0);
bcopy(data, &tp->t_winsize, sizeof(struct winsize));
tty_signal_pgrp(tp, SIGWINCH);
return (0);
case TIOCEXCL:
tp->t_flags |= TF_EXCLUDE;
return (0);
case TIOCNXCL:
tp->t_flags &= ~TF_EXCLUDE;
return (0);
case TIOCOUTQ:
*(unsigned int *)data = ttyoutq_bytesused(&tp->t_outq);
return (0);
case TIOCSTOP:
tp->t_flags |= TF_STOPPED;
ttydevsw_pktnotify(tp, TIOCPKT_STOP);
return (0);
case TIOCSTART:
tp->t_flags &= ~TF_STOPPED;
ttydevsw_outwakeup(tp);
ttydevsw_pktnotify(tp, TIOCPKT_START);
return (0);
case TIOCSTAT:
tty_info(tp);
return (0);
}
#ifdef COMPAT_43TTY
return tty_ioctl_compat(tp, cmd, data, td);
#else /* !COMPAT_43TTY */
return (ENOIOCTL);
#endif /* COMPAT_43TTY */
}
int
tty_ioctl(struct tty *tp, u_long cmd, void *data, struct thread *td)
{
int error;
tty_lock_assert(tp, MA_OWNED);
if (tty_gone(tp))
return (ENXIO);
error = ttydevsw_ioctl(tp, cmd, data, td);
if (error == ENOIOCTL)
error = tty_generic_ioctl(tp, cmd, data, td);
return (error);
}
dev_t
tty_udev(struct tty *tp)
{
if (tp->t_dev)
return dev2udev(tp->t_dev);
else
return NODEV;
}
int
tty_checkoutq(struct tty *tp)
{
/* 256 bytes should be enough to print a log message. */
return (ttyoutq_bytesleft(&tp->t_outq) >= 256);
}
void
tty_hiwat_in_block(struct tty *tp)
{
if ((tp->t_flags & TF_HIWAT_IN) == 0 &&
tp->t_termios.c_iflag & IXOFF &&
tp->t_termios.c_cc[VSTOP] != _POSIX_VDISABLE) {
/*
* Input flow control. Only enter the high watermark when we
* can successfully store the VSTOP character.
*/
if (ttyoutq_write_nofrag(&tp->t_outq,
&tp->t_termios.c_cc[VSTOP], 1) == 0)
tp->t_flags |= TF_HIWAT_IN;
} else {
/* No input flow control. */
tp->t_flags |= TF_HIWAT_IN;
}
}
void
tty_hiwat_in_unblock(struct tty *tp)
{
if (tp->t_flags & TF_HIWAT_IN &&
tp->t_termios.c_iflag & IXOFF &&
tp->t_termios.c_cc[VSTART] != _POSIX_VDISABLE) {
/*
* Input flow control. Only leave the high watermark when we
* can successfully store the VSTART character.
*/
if (ttyoutq_write_nofrag(&tp->t_outq,
&tp->t_termios.c_cc[VSTART], 1) == 0)
tp->t_flags &= ~TF_HIWAT_IN;
} else {
/* No input flow control. */
tp->t_flags &= ~TF_HIWAT_IN;
}
if (!tty_gone(tp))
ttydevsw_inwakeup(tp);
}
static int
ttyhook_defrint(struct tty *tp, char c, int flags)
{
if (ttyhook_rint_bypass(tp, &c, 1) != 1)
return (-1);
return (0);
}
int
ttyhook_register(struct tty **rtp, struct thread *td, int fd,
struct ttyhook *th, void *softc)
{
struct tty *tp;
struct file *fp;
struct cdev *dev;
struct cdevsw *cdp;
int error;
/* Validate the file descriptor. */
if (fget(td, fd, &fp) != 0)
return (EINVAL);
/* Make sure the vnode is bound to a character device. */
error = EINVAL;
if (fp->f_type != DTYPE_VNODE || fp->f_vnode->v_type != VCHR ||
fp->f_vnode->v_rdev == NULL)
goto done1;
dev = fp->f_vnode->v_rdev;
/* Make sure it is a TTY. */
cdp = dev_refthread(dev);
if (cdp == NULL)
goto done1;
if ((cdp->d_flags & D_TTY) == 0)
goto done2;
tp = dev->si_drv1;
/* Try to attach the hook to the TTY. */
error = EBUSY;
tty_lock(tp);
MPASS((tp->t_hook == NULL) == ((tp->t_flags & TF_HOOK) == 0));
if (tp->t_flags & TF_HOOK)
goto done3;
tp->t_flags |= TF_HOOK;
tp->t_hook = th;
tp->t_hooksoftc = softc;
*rtp = tp;
error = 0;
/* Maybe we can switch into bypass mode now. */
ttydisc_optimize(tp);
/* Silently convert rint() calls to rint_bypass() when possible. */
if (!ttyhook_hashook(tp, rint) && ttyhook_hashook(tp, rint_bypass))
th->th_rint = ttyhook_defrint;
done3: tty_unlock(tp);
done2: dev_relthread(dev);
done1: fdrop(fp, td);
return (error);
}
void
ttyhook_unregister(struct tty *tp)
{
tty_lock_assert(tp, MA_OWNED);
MPASS(tp->t_flags & TF_HOOK);
/* Disconnect the hook. */
tp->t_flags &= ~TF_HOOK;
tp->t_hook = NULL;
/* Maybe we need to leave bypass mode. */
ttydisc_optimize(tp);
/* Maybe deallocate the TTY as well. */
tty_rel_free(tp);
}
#include "opt_ddb.h"
#ifdef DDB
#include <ddb/ddb.h>
static struct {
int flag;
char val;
} ttystates[] = {
#if 0
{ TF_NOPREFIX, 'N' },
#endif
{ TF_INITLOCK, 'I' },
{ TF_CALLOUT, 'C' },
/* Keep these together -> 'Oi' and 'Oo'. */
{ TF_OPENED, 'O' },
{ TF_OPENED_IN, 'i' },
{ TF_OPENED_OUT,'o' },
{ TF_GONE, 'G' },
{ TF_OPENCLOSE, 'B' },
{ TF_ASYNC, 'Y' },
{ TF_LITERAL, 'L' },
/* Keep these together -> 'Hi' and 'Ho'. */
{ TF_HIWAT, 'H' },
{ TF_HIWAT_IN, 'i' },
{ TF_HIWAT_OUT, 'o' },
{ TF_STOPPED, 'S' },
{ TF_EXCLUDE, 'X' },
{ TF_BYPASS, 'l' },
{ TF_ZOMBIE, 'Z' },
{ TF_HOOK, 's' },
{ 0, '\0' },
};
/* DDB command to show TTY statistics. */
DB_SHOW_COMMAND(ttys, db_show_ttys)
{
struct tty *tp;
size_t isiz, osiz;
int i, j;
/* Make the output look like `pstat -t'. */
db_printf(" LINE INQ CAN LIN LOW OUTQ USE LOW "
"COL SESS PGID STATE\n");
TAILQ_FOREACH(tp, &tty_list, t_list) {
isiz = tp->t_inq.ti_nblocks * TTYINQ_DATASIZE;
osiz = tp->t_outq.to_nblocks * TTYOUTQ_DATASIZE;
db_printf("%10s %5zu %4u %4u %4zu %5zu %4u %4zu %5u %5d %5d ",
tty_devname(tp),
isiz,
tp->t_inq.ti_linestart - tp->t_inq.ti_begin,
tp->t_inq.ti_end - tp->t_inq.ti_linestart,
isiz - tp->t_inlow,
osiz,
tp->t_outq.to_end - tp->t_outq.to_begin,
osiz - tp->t_outlow,
tp->t_column,
tp->t_session ? tp->t_session->s_sid : 0,
tp->t_pgrp ? tp->t_pgrp->pg_id : 0);
/* Flag bits. */
for (i = j = 0; ttystates[i].flag; i++)
if (tp->t_flags & ttystates[i].flag) {
db_printf("%c", ttystates[i].val);
j++;
}
if (j == 0)
db_printf("-");
db_printf("\n");
}
}
#endif /* DDB */
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