The Design and Implementation of the FreeBSD Operating System, Second Edition
Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)


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FreeBSD/Linux Kernel Cross Reference
sys/kern/tty.c

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    1 /*-
    2  * Copyright (c) 2008 Ed Schouten <ed@FreeBSD.org>
    3  * All rights reserved.
    4  *
    5  * Portions of this software were developed under sponsorship from Snow
    6  * B.V., the Netherlands.
    7  *
    8  * Redistribution and use in source and binary forms, with or without
    9  * modification, are permitted provided that the following conditions
   10  * are met:
   11  * 1. Redistributions of source code must retain the above copyright
   12  *    notice, this list of conditions and the following disclaimer.
   13  * 2. Redistributions in binary form must reproduce the above copyright
   14  *    notice, this list of conditions and the following disclaimer in the
   15  *    documentation and/or other materials provided with the distribution.
   16  *
   17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
   18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
   21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   27  * SUCH DAMAGE.
   28  */
   29 
   30 #include <sys/cdefs.h>
   31 __FBSDID("$FreeBSD: releng/8.0/sys/kern/tty.c 195444 2009-07-08 10:21:52Z ed $");
   32 
   33 #include "opt_compat.h"
   34 
   35 #include <sys/param.h>
   36 #include <sys/conf.h>
   37 #include <sys/cons.h>
   38 #include <sys/fcntl.h>
   39 #include <sys/file.h>
   40 #include <sys/filedesc.h>
   41 #include <sys/filio.h>
   42 #ifdef COMPAT_43TTY
   43 #include <sys/ioctl_compat.h>
   44 #endif /* COMPAT_43TTY */
   45 #include <sys/kernel.h>
   46 #include <sys/limits.h>
   47 #include <sys/malloc.h>
   48 #include <sys/mount.h>
   49 #include <sys/poll.h>
   50 #include <sys/priv.h>
   51 #include <sys/proc.h>
   52 #include <sys/serial.h>
   53 #include <sys/signal.h>
   54 #include <sys/stat.h>
   55 #include <sys/sx.h>
   56 #include <sys/sysctl.h>
   57 #include <sys/systm.h>
   58 #include <sys/tty.h>
   59 #include <sys/ttycom.h>
   60 #define TTYDEFCHARS
   61 #include <sys/ttydefaults.h>
   62 #undef TTYDEFCHARS
   63 #include <sys/ucred.h>
   64 #include <sys/vnode.h>
   65 
   66 #include <machine/stdarg.h>
   67 
   68 static MALLOC_DEFINE(M_TTY, "tty", "tty device");
   69 
   70 static void tty_rel_free(struct tty *tp);
   71 
   72 static TAILQ_HEAD(, tty) tty_list = TAILQ_HEAD_INITIALIZER(tty_list);
   73 static struct sx tty_list_sx;
   74 SX_SYSINIT(tty_list, &tty_list_sx, "tty list");
   75 static unsigned int tty_list_count = 0;
   76 
   77 /* Character device of /dev/console. */
   78 static struct cdev      *dev_console;
   79 static const char       *dev_console_filename;
   80 
   81 /*
   82  * Flags that are supported and stored by this implementation.
   83  */
   84 #define TTYSUP_IFLAG    (IGNBRK|BRKINT|IGNPAR|PARMRK|INPCK|ISTRIP|\
   85                         INLCR|IGNCR|ICRNL|IXON|IXOFF|IXANY|IMAXBEL)
   86 #define TTYSUP_OFLAG    (OPOST|ONLCR|TAB3|ONOEOT|OCRNL|ONOCR|ONLRET)
   87 #define TTYSUP_LFLAG    (ECHOKE|ECHOE|ECHOK|ECHO|ECHONL|ECHOPRT|\
   88                         ECHOCTL|ISIG|ICANON|ALTWERASE|IEXTEN|TOSTOP|\
   89                         FLUSHO|NOKERNINFO|NOFLSH)
   90 #define TTYSUP_CFLAG    (CIGNORE|CSIZE|CSTOPB|CREAD|PARENB|PARODD|\
   91                         HUPCL|CLOCAL|CCTS_OFLOW|CRTS_IFLOW|CDTR_IFLOW|\
   92                         CDSR_OFLOW|CCAR_OFLOW)
   93 
   94 #define TTY_CALLOUT(tp,d) ((d) != (tp)->t_dev && (d) != dev_console)
   95 
   96 /*
   97  * Set TTY buffer sizes.
   98  */
   99 
  100 #define TTYBUF_MAX      65536
  101 
  102 static void
  103 tty_watermarks(struct tty *tp)
  104 {
  105         size_t bs;
  106 
  107         /* Provide an input buffer for 0.2 seconds of data. */
  108         bs = MIN(tp->t_termios.c_ispeed / 5, TTYBUF_MAX);
  109         ttyinq_setsize(&tp->t_inq, tp, bs);
  110 
  111         /* Set low watermark at 10% (when 90% is available). */
  112         tp->t_inlow = (ttyinq_getsize(&tp->t_inq) * 9) / 10;
  113 
  114         /* Provide an ouput buffer for 0.2 seconds of data. */
  115         bs = MIN(tp->t_termios.c_ospeed / 5, TTYBUF_MAX);
  116         ttyoutq_setsize(&tp->t_outq, tp, bs);
  117 
  118         /* Set low watermark at 10% (when 90% is available). */
  119         tp->t_outlow = (ttyoutq_getsize(&tp->t_outq) * 9) / 10;
  120 }
  121 
  122 static int
  123 tty_drain(struct tty *tp)
  124 {
  125         int error;
  126 
  127         if (ttyhook_hashook(tp, getc_inject))
  128                 /* buffer is inaccessible */
  129                 return (0);
  130 
  131         while (ttyoutq_bytesused(&tp->t_outq) > 0) {
  132                 ttydevsw_outwakeup(tp);
  133                 /* Could be handled synchronously. */
  134                 if (ttyoutq_bytesused(&tp->t_outq) == 0)
  135                         return (0);
  136 
  137                 /* Wait for data to be drained. */
  138                 error = tty_wait(tp, &tp->t_outwait);
  139                 if (error)
  140                         return (error);
  141         }
  142 
  143         return (0);
  144 }
  145 
  146 /*
  147  * Though ttydev_enter() and ttydev_leave() seem to be related, they
  148  * don't have to be used together. ttydev_enter() is used by the cdev
  149  * operations to prevent an actual operation from being processed when
  150  * the TTY has been abandoned. ttydev_leave() is used by ttydev_open()
  151  * and ttydev_close() to determine whether per-TTY data should be
  152  * deallocated.
  153  */
  154 
  155 static __inline int
  156 ttydev_enter(struct tty *tp)
  157 {
  158         tty_lock(tp);
  159 
  160         if (tty_gone(tp) || !tty_opened(tp)) {
  161                 /* Device is already gone. */
  162                 tty_unlock(tp);
  163                 return (ENXIO);
  164         }
  165 
  166         return (0);
  167 }
  168 
  169 static void
  170 ttydev_leave(struct tty *tp)
  171 {
  172         tty_lock_assert(tp, MA_OWNED);
  173 
  174         if (tty_opened(tp) || tp->t_flags & TF_OPENCLOSE) {
  175                 /* Device is still opened somewhere. */
  176                 tty_unlock(tp);
  177                 return;
  178         }
  179 
  180         tp->t_flags |= TF_OPENCLOSE;
  181 
  182         /* Stop asynchronous I/O. */
  183         funsetown(&tp->t_sigio);
  184 
  185         /* Remove console TTY. */
  186         if (constty == tp)
  187                 constty_clear();
  188 
  189         /* Drain any output. */
  190         MPASS((tp->t_flags & TF_STOPPED) == 0);
  191         if (!tty_gone(tp))
  192                 tty_drain(tp);
  193 
  194         ttydisc_close(tp);
  195 
  196         /* Destroy associated buffers already. */
  197         ttyinq_free(&tp->t_inq);
  198         tp->t_inlow = 0;
  199         ttyoutq_free(&tp->t_outq);
  200         tp->t_outlow = 0;
  201 
  202         knlist_clear(&tp->t_inpoll.si_note, 1);
  203         knlist_clear(&tp->t_outpoll.si_note, 1);
  204 
  205         if (!tty_gone(tp))
  206                 ttydevsw_close(tp);
  207 
  208         tp->t_flags &= ~TF_OPENCLOSE;
  209         cv_broadcast(&tp->t_dcdwait);
  210         tty_rel_free(tp);
  211 }
  212 
  213 /*
  214  * Operations that are exposed through the character device in /dev.
  215  */
  216 static int
  217 ttydev_open(struct cdev *dev, int oflags, int devtype, struct thread *td)
  218 {
  219         struct tty *tp = dev->si_drv1;
  220         int error = 0;
  221 
  222         tty_lock(tp);
  223         if (tty_gone(tp)) {
  224                 /* Device is already gone. */
  225                 tty_unlock(tp);
  226                 return (ENXIO);
  227         }
  228 
  229         /*
  230          * Block when other processes are currently opening or closing
  231          * the TTY.
  232          */
  233         while (tp->t_flags & TF_OPENCLOSE) {
  234                 error = tty_wait(tp, &tp->t_dcdwait);
  235                 if (error != 0) {
  236                         tty_unlock(tp);
  237                         return (error);
  238                 }
  239         }
  240         tp->t_flags |= TF_OPENCLOSE;
  241 
  242         /*
  243          * Make sure the "tty" and "cua" device cannot be opened at the
  244          * same time.
  245          */
  246         if (TTY_CALLOUT(tp, dev)) {
  247                 if (tp->t_flags & TF_OPENED_IN) {
  248                         error = EBUSY;
  249                         goto done;
  250                 }
  251         } else {
  252                 if (tp->t_flags & TF_OPENED_OUT) {
  253                         error = EBUSY;
  254                         goto done;
  255                 }
  256         }
  257 
  258         if (tp->t_flags & TF_EXCLUDE && priv_check(td, PRIV_TTY_EXCLUSIVE)) {
  259                 error = EBUSY;
  260                 goto done;
  261         }
  262 
  263         if (!tty_opened(tp)) {
  264                 /* Set proper termios flags. */
  265                 if (TTY_CALLOUT(tp, dev)) {
  266                         tp->t_termios = tp->t_termios_init_out;
  267                 } else {
  268                         tp->t_termios = tp->t_termios_init_in;
  269                 }
  270                 ttydevsw_param(tp, &tp->t_termios);
  271 
  272                 ttydevsw_modem(tp, SER_DTR|SER_RTS, 0);
  273 
  274                 error = ttydevsw_open(tp);
  275                 if (error != 0)
  276                         goto done;
  277 
  278                 ttydisc_open(tp);
  279                 tty_watermarks(tp);
  280         }
  281 
  282         /* Wait for Carrier Detect. */
  283         if (!TTY_CALLOUT(tp, dev) && (oflags & O_NONBLOCK) == 0 &&
  284             (tp->t_termios.c_cflag & CLOCAL) == 0) {
  285                 while ((ttydevsw_modem(tp, 0, 0) & SER_DCD) == 0) {
  286                         error = tty_wait(tp, &tp->t_dcdwait);
  287                         if (error != 0)
  288                                 goto done;
  289                 }
  290         }
  291 
  292         if (dev == dev_console)
  293                 tp->t_flags |= TF_OPENED_CONS;
  294         else if (TTY_CALLOUT(tp, dev))
  295                 tp->t_flags |= TF_OPENED_OUT;
  296         else
  297                 tp->t_flags |= TF_OPENED_IN;
  298 
  299 done:   tp->t_flags &= ~TF_OPENCLOSE;
  300         cv_broadcast(&tp->t_dcdwait);
  301         ttydev_leave(tp);
  302 
  303         return (error);
  304 }
  305 
  306 static int
  307 ttydev_close(struct cdev *dev, int fflag, int devtype, struct thread *td)
  308 {
  309         struct tty *tp = dev->si_drv1;
  310 
  311         tty_lock(tp);
  312 
  313         /*
  314          * Don't actually close the device if it is being used as the
  315          * console.
  316          */
  317         MPASS((tp->t_flags & TF_OPENED) != TF_OPENED);
  318         if (dev == dev_console)
  319                 tp->t_flags &= ~TF_OPENED_CONS;
  320         else
  321                 tp->t_flags &= ~(TF_OPENED_IN|TF_OPENED_OUT);
  322 
  323         if (tp->t_flags & TF_OPENED) {
  324                 tty_unlock(tp);
  325                 return (0);
  326         }
  327 
  328         /*
  329          * This can only be called once. The callin and the callout
  330          * devices cannot be opened at the same time.
  331          */
  332         tp->t_flags &= ~(TF_EXCLUDE|TF_STOPPED);
  333 
  334         /* Properly wake up threads that are stuck - revoke(). */
  335         tp->t_revokecnt++;
  336         tty_wakeup(tp, FREAD|FWRITE);
  337         cv_broadcast(&tp->t_bgwait);
  338         cv_broadcast(&tp->t_dcdwait);
  339 
  340         ttydev_leave(tp);
  341 
  342         return (0);
  343 }
  344 
  345 static __inline int
  346 tty_is_ctty(struct tty *tp, struct proc *p)
  347 {
  348         tty_lock_assert(tp, MA_OWNED);
  349 
  350         return (p->p_session == tp->t_session && p->p_flag & P_CONTROLT);
  351 }
  352 
  353 static int
  354 tty_wait_background(struct tty *tp, struct thread *td, int sig)
  355 {
  356         struct proc *p = td->td_proc;
  357         struct pgrp *pg;
  358         int error;
  359 
  360         MPASS(sig == SIGTTIN || sig == SIGTTOU);
  361         tty_lock_assert(tp, MA_OWNED);
  362 
  363         for (;;) {
  364                 PROC_LOCK(p);
  365                 /*
  366                  * The process should only sleep, when:
  367                  * - This terminal is the controling terminal
  368                  * - Its process group is not the foreground process
  369                  *   group
  370                  * - The parent process isn't waiting for the child to
  371                  *   exit
  372                  * - the signal to send to the process isn't masked
  373                  */
  374                 if (!tty_is_ctty(tp, p) || p->p_pgrp == tp->t_pgrp) {
  375                         /* Allow the action to happen. */
  376                         PROC_UNLOCK(p);
  377                         return (0);
  378                 }
  379 
  380                 if (SIGISMEMBER(p->p_sigacts->ps_sigignore, sig) ||
  381                     SIGISMEMBER(td->td_sigmask, sig)) {
  382                         /* Only allow them in write()/ioctl(). */
  383                         PROC_UNLOCK(p);
  384                         return (sig == SIGTTOU ? 0 : EIO);
  385                 }
  386 
  387                 pg = p->p_pgrp;
  388                 if (p->p_flag & P_PPWAIT || pg->pg_jobc == 0) {
  389                         /* Don't allow the action to happen. */
  390                         PROC_UNLOCK(p);
  391                         return (EIO);
  392                 }
  393                 PROC_UNLOCK(p);
  394 
  395                 /*
  396                  * Send the signal and sleep until we're the new
  397                  * foreground process group.
  398                  */
  399                 PGRP_LOCK(pg);
  400                 pgsignal(pg, sig, 1);
  401                 PGRP_UNLOCK(pg);
  402 
  403                 error = tty_wait(tp, &tp->t_bgwait);
  404                 if (error)
  405                         return (error);
  406         }
  407 }
  408 
  409 static int
  410 ttydev_read(struct cdev *dev, struct uio *uio, int ioflag)
  411 {
  412         struct tty *tp = dev->si_drv1;
  413         int error;
  414 
  415         error = ttydev_enter(tp);
  416         if (error)
  417                 goto done;
  418 
  419         error = tty_wait_background(tp, curthread, SIGTTIN);
  420         if (error) {
  421                 tty_unlock(tp);
  422                 goto done;
  423         }
  424 
  425         error = ttydisc_read(tp, uio, ioflag);
  426         tty_unlock(tp);
  427 
  428         /*
  429          * The read() call should not throw an error when the device is
  430          * being destroyed. Silently convert it to an EOF.
  431          */
  432 done:   if (error == ENXIO)
  433                 error = 0;
  434         return (error);
  435 }
  436 
  437 static int
  438 ttydev_write(struct cdev *dev, struct uio *uio, int ioflag)
  439 {
  440         struct tty *tp = dev->si_drv1;
  441         int error;
  442 
  443         error = ttydev_enter(tp);
  444         if (error)
  445                 return (error);
  446 
  447         if (tp->t_termios.c_lflag & TOSTOP) {
  448                 error = tty_wait_background(tp, curthread, SIGTTOU);
  449                 if (error)
  450                         goto done;
  451         }
  452 
  453         if (ioflag & IO_NDELAY && tp->t_flags & TF_BUSY_OUT) {
  454                 /* Allow non-blocking writes to bypass serialization. */
  455                 error = ttydisc_write(tp, uio, ioflag);
  456         } else {
  457                 /* Serialize write() calls. */
  458                 while (tp->t_flags & TF_BUSY_OUT) {
  459                         error = tty_wait(tp, &tp->t_outserwait);
  460                         if (error)
  461                                 goto done;
  462                 }
  463  
  464                 tp->t_flags |= TF_BUSY_OUT;
  465                 error = ttydisc_write(tp, uio, ioflag);
  466                 tp->t_flags &= ~TF_BUSY_OUT;
  467                 cv_signal(&tp->t_outserwait);
  468         }
  469 
  470 done:   tty_unlock(tp);
  471         return (error);
  472 }
  473 
  474 static int
  475 ttydev_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag,
  476     struct thread *td)
  477 {
  478         struct tty *tp = dev->si_drv1;
  479         int error;
  480 
  481         error = ttydev_enter(tp);
  482         if (error)
  483                 return (error);
  484 
  485         switch (cmd) {
  486         case TIOCCBRK:
  487         case TIOCCONS:
  488         case TIOCDRAIN:
  489         case TIOCEXCL:
  490         case TIOCFLUSH:
  491         case TIOCNXCL:
  492         case TIOCSBRK:
  493         case TIOCSCTTY:
  494         case TIOCSETA:
  495         case TIOCSETAF:
  496         case TIOCSETAW:
  497         case TIOCSPGRP:
  498         case TIOCSTART:
  499         case TIOCSTAT:
  500         case TIOCSTOP:
  501         case TIOCSWINSZ:
  502 #if 0
  503         case TIOCSDRAINWAIT:
  504         case TIOCSETD:
  505         case TIOCSTI:
  506 #endif
  507 #ifdef COMPAT_43TTY
  508         case  TIOCLBIC:
  509         case  TIOCLBIS:
  510         case  TIOCLSET:
  511         case  TIOCSETC:
  512         case OTIOCSETD:
  513         case  TIOCSETN:
  514         case  TIOCSETP:
  515         case  TIOCSLTC:
  516 #endif /* COMPAT_43TTY */
  517                 /*
  518                  * If the ioctl() causes the TTY to be modified, let it
  519                  * wait in the background.
  520                  */
  521                 error = tty_wait_background(tp, curthread, SIGTTOU);
  522                 if (error)
  523                         goto done;
  524         }
  525 
  526         error = tty_ioctl(tp, cmd, data, td);
  527 done:   tty_unlock(tp);
  528 
  529         return (error);
  530 }
  531 
  532 static int
  533 ttydev_poll(struct cdev *dev, int events, struct thread *td)
  534 {
  535         struct tty *tp = dev->si_drv1;
  536         int error, revents = 0;
  537 
  538         error = ttydev_enter(tp);
  539         if (error)
  540                 return ((events & (POLLIN|POLLRDNORM)) | POLLHUP);
  541 
  542         if (events & (POLLIN|POLLRDNORM)) {
  543                 /* See if we can read something. */
  544                 if (ttydisc_read_poll(tp) > 0)
  545                         revents |= events & (POLLIN|POLLRDNORM);
  546         }
  547 
  548         if (tp->t_flags & TF_ZOMBIE) {
  549                 /* Hangup flag on zombie state. */
  550                 revents |= POLLHUP;
  551         } else if (events & (POLLOUT|POLLWRNORM)) {
  552                 /* See if we can write something. */
  553                 if (ttydisc_write_poll(tp) > 0)
  554                         revents |= events & (POLLOUT|POLLWRNORM);
  555         }
  556 
  557         if (revents == 0) {
  558                 if (events & (POLLIN|POLLRDNORM))
  559                         selrecord(td, &tp->t_inpoll);
  560                 if (events & (POLLOUT|POLLWRNORM))
  561                         selrecord(td, &tp->t_outpoll);
  562         }
  563 
  564         tty_unlock(tp);
  565 
  566         return (revents);
  567 }
  568 
  569 static int
  570 ttydev_mmap(struct cdev *dev, vm_offset_t offset, vm_paddr_t *paddr, int nprot)
  571 {
  572         struct tty *tp = dev->si_drv1;
  573         int error;
  574 
  575         /* Handle mmap() through the driver. */
  576 
  577         error = ttydev_enter(tp);
  578         if (error)
  579                 return (-1);
  580         error = ttydevsw_mmap(tp, offset, paddr, nprot);
  581         tty_unlock(tp);
  582 
  583         return (error);
  584 }
  585 
  586 /*
  587  * kqueue support.
  588  */
  589 
  590 static void
  591 tty_kqops_read_detach(struct knote *kn)
  592 {
  593         struct tty *tp = kn->kn_hook;
  594 
  595         knlist_remove(&tp->t_inpoll.si_note, kn, 0);
  596 }
  597 
  598 static int
  599 tty_kqops_read_event(struct knote *kn, long hint)
  600 {
  601         struct tty *tp = kn->kn_hook;
  602 
  603         tty_lock_assert(tp, MA_OWNED);
  604 
  605         if (tty_gone(tp) || tp->t_flags & TF_ZOMBIE) {
  606                 kn->kn_flags |= EV_EOF;
  607                 return (1);
  608         } else {
  609                 kn->kn_data = ttydisc_read_poll(tp);
  610                 return (kn->kn_data > 0);
  611         }
  612 }
  613 
  614 static void
  615 tty_kqops_write_detach(struct knote *kn)
  616 {
  617         struct tty *tp = kn->kn_hook;
  618 
  619         knlist_remove(&tp->t_outpoll.si_note, kn, 0);
  620 }
  621 
  622 static int
  623 tty_kqops_write_event(struct knote *kn, long hint)
  624 {
  625         struct tty *tp = kn->kn_hook;
  626 
  627         tty_lock_assert(tp, MA_OWNED);
  628 
  629         if (tty_gone(tp)) {
  630                 kn->kn_flags |= EV_EOF;
  631                 return (1);
  632         } else {
  633                 kn->kn_data = ttydisc_write_poll(tp);
  634                 return (kn->kn_data > 0);
  635         }
  636 }
  637 
  638 static struct filterops tty_kqops_read =
  639     { 1, NULL, tty_kqops_read_detach, tty_kqops_read_event };
  640 static struct filterops tty_kqops_write =
  641     { 1, NULL, tty_kqops_write_detach, tty_kqops_write_event };
  642 
  643 static int
  644 ttydev_kqfilter(struct cdev *dev, struct knote *kn)
  645 {
  646         struct tty *tp = dev->si_drv1;
  647         int error;
  648 
  649         error = ttydev_enter(tp);
  650         if (error)
  651                 return (error);
  652 
  653         switch (kn->kn_filter) {
  654         case EVFILT_READ:
  655                 kn->kn_hook = tp;
  656                 kn->kn_fop = &tty_kqops_read;
  657                 knlist_add(&tp->t_inpoll.si_note, kn, 1);
  658                 break;
  659         case EVFILT_WRITE:
  660                 kn->kn_hook = tp;
  661                 kn->kn_fop = &tty_kqops_write;
  662                 knlist_add(&tp->t_outpoll.si_note, kn, 1);
  663                 break;
  664         default:
  665                 error = EINVAL;
  666                 break;
  667         }
  668 
  669         tty_unlock(tp);
  670         return (error);
  671 }
  672 
  673 static struct cdevsw ttydev_cdevsw = {
  674         .d_version      = D_VERSION,
  675         .d_open         = ttydev_open,
  676         .d_close        = ttydev_close,
  677         .d_read         = ttydev_read,
  678         .d_write        = ttydev_write,
  679         .d_ioctl        = ttydev_ioctl,
  680         .d_kqfilter     = ttydev_kqfilter,
  681         .d_poll         = ttydev_poll,
  682         .d_mmap         = ttydev_mmap,
  683         .d_name         = "ttydev",
  684         .d_flags        = D_TTY,
  685 };
  686 
  687 /*
  688  * Init/lock-state devices
  689  */
  690 
  691 static int
  692 ttyil_open(struct cdev *dev, int oflags, int devtype, struct thread *td)
  693 {
  694         struct tty *tp = dev->si_drv1;
  695         int error = 0;
  696 
  697         tty_lock(tp);
  698         if (tty_gone(tp))
  699                 error = ENODEV;
  700         tty_unlock(tp);
  701 
  702         return (error);
  703 }
  704 
  705 static int
  706 ttyil_close(struct cdev *dev, int flag, int mode, struct thread *td)
  707 {
  708         return (0);
  709 }
  710 
  711 static int
  712 ttyil_rdwr(struct cdev *dev, struct uio *uio, int ioflag)
  713 {
  714         return (ENODEV);
  715 }
  716 
  717 static int
  718 ttyil_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag,
  719     struct thread *td)
  720 {
  721         struct tty *tp = dev->si_drv1;
  722         int error = 0;
  723 
  724         tty_lock(tp);
  725         if (tty_gone(tp)) {
  726                 error = ENODEV;
  727                 goto done;
  728         }
  729 
  730         switch (cmd) {
  731         case TIOCGETA:
  732                 /* Obtain terminal flags through tcgetattr(). */
  733                 *(struct termios*)data = *(struct termios*)dev->si_drv2;
  734                 break;
  735         case TIOCSETA:
  736                 /* Set terminal flags through tcsetattr(). */
  737                 error = priv_check(td, PRIV_TTY_SETA);
  738                 if (error)
  739                         break;
  740                 *(struct termios*)dev->si_drv2 = *(struct termios*)data;
  741                 break;
  742         case TIOCGETD:
  743                 *(int *)data = TTYDISC;
  744                 break;
  745         case TIOCGWINSZ:
  746                 bzero(data, sizeof(struct winsize));
  747                 break;
  748         default:
  749                 error = ENOTTY;
  750         }
  751 
  752 done:   tty_unlock(tp);
  753         return (error);
  754 }
  755 
  756 static struct cdevsw ttyil_cdevsw = {
  757         .d_version      = D_VERSION,
  758         .d_open         = ttyil_open,
  759         .d_close        = ttyil_close,
  760         .d_read         = ttyil_rdwr,
  761         .d_write        = ttyil_rdwr,
  762         .d_ioctl        = ttyil_ioctl,
  763         .d_name         = "ttyil",
  764         .d_flags        = D_TTY,
  765 };
  766 
  767 static void
  768 tty_init_termios(struct tty *tp)
  769 {
  770         struct termios *t = &tp->t_termios_init_in;
  771 
  772         t->c_cflag = TTYDEF_CFLAG;
  773         t->c_iflag = TTYDEF_IFLAG;
  774         t->c_lflag = TTYDEF_LFLAG;
  775         t->c_oflag = TTYDEF_OFLAG;
  776         t->c_ispeed = TTYDEF_SPEED;
  777         t->c_ospeed = TTYDEF_SPEED;
  778         memcpy(&t->c_cc, ttydefchars, sizeof ttydefchars);
  779 
  780         tp->t_termios_init_out = *t;
  781 }
  782 
  783 void
  784 tty_init_console(struct tty *tp, speed_t s)
  785 {
  786         struct termios *ti = &tp->t_termios_init_in;
  787         struct termios *to = &tp->t_termios_init_out;
  788 
  789         if (s != 0) {
  790                 ti->c_ispeed = ti->c_ospeed = s;
  791                 to->c_ispeed = to->c_ospeed = s;
  792         }
  793 
  794         ti->c_cflag |= CLOCAL;
  795         to->c_cflag |= CLOCAL;
  796 }
  797 
  798 /*
  799  * Standard device routine implementations, mostly meant for
  800  * pseudo-terminal device drivers. When a driver creates a new terminal
  801  * device class, missing routines are patched.
  802  */
  803 
  804 static int
  805 ttydevsw_defopen(struct tty *tp)
  806 {
  807 
  808         return (0);
  809 }
  810 
  811 static void
  812 ttydevsw_defclose(struct tty *tp)
  813 {
  814 }
  815 
  816 static void
  817 ttydevsw_defoutwakeup(struct tty *tp)
  818 {
  819 
  820         panic("Terminal device has output, while not implemented");
  821 }
  822 
  823 static void
  824 ttydevsw_definwakeup(struct tty *tp)
  825 {
  826 }
  827 
  828 static int
  829 ttydevsw_defioctl(struct tty *tp, u_long cmd, caddr_t data, struct thread *td)
  830 {
  831 
  832         return (ENOIOCTL);
  833 }
  834 
  835 static int
  836 ttydevsw_defparam(struct tty *tp, struct termios *t)
  837 {
  838 
  839         /* Use a fake baud rate, we're not a real device. */
  840         t->c_ispeed = t->c_ospeed = TTYDEF_SPEED;
  841 
  842         return (0);
  843 }
  844 
  845 static int
  846 ttydevsw_defmodem(struct tty *tp, int sigon, int sigoff)
  847 {
  848 
  849         /* Simulate a carrier to make the TTY layer happy. */
  850         return (SER_DCD);
  851 }
  852 
  853 static int
  854 ttydevsw_defmmap(struct tty *tp, vm_offset_t offset, vm_paddr_t *paddr,
  855     int nprot)
  856 {
  857 
  858         return (-1);
  859 }
  860 
  861 static void
  862 ttydevsw_defpktnotify(struct tty *tp, char event)
  863 {
  864 }
  865 
  866 static void
  867 ttydevsw_deffree(void *softc)
  868 {
  869 
  870         panic("Terminal device freed without a free-handler");
  871 }
  872 
  873 /*
  874  * TTY allocation and deallocation. TTY devices can be deallocated when
  875  * the driver doesn't use it anymore, when the TTY isn't a session's
  876  * controlling TTY and when the device node isn't opened through devfs.
  877  */
  878 
  879 struct tty *
  880 tty_alloc(struct ttydevsw *tsw, void *sc)
  881 {
  882 
  883         return (tty_alloc_mutex(tsw, sc, NULL));
  884 }
  885 
  886 struct tty *
  887 tty_alloc_mutex(struct ttydevsw *tsw, void *sc, struct mtx *mutex)
  888 {
  889         struct tty *tp;
  890 
  891         /* Make sure the driver defines all routines. */
  892 #define PATCH_FUNC(x) do {                              \
  893         if (tsw->tsw_ ## x == NULL)                     \
  894                 tsw->tsw_ ## x = ttydevsw_def ## x;     \
  895 } while (0)
  896         PATCH_FUNC(open);
  897         PATCH_FUNC(close);
  898         PATCH_FUNC(outwakeup);
  899         PATCH_FUNC(inwakeup);
  900         PATCH_FUNC(ioctl);
  901         PATCH_FUNC(param);
  902         PATCH_FUNC(modem);
  903         PATCH_FUNC(mmap);
  904         PATCH_FUNC(pktnotify);
  905         PATCH_FUNC(free);
  906 #undef PATCH_FUNC
  907 
  908         tp = malloc(sizeof(struct tty), M_TTY, M_WAITOK|M_ZERO);
  909         tp->t_devsw = tsw;
  910         tp->t_devswsoftc = sc;
  911         tp->t_flags = tsw->tsw_flags;
  912 
  913         tty_init_termios(tp);
  914 
  915         cv_init(&tp->t_inwait, "ttyin");
  916         cv_init(&tp->t_outwait, "ttyout");
  917         cv_init(&tp->t_outserwait, "ttyosr");
  918         cv_init(&tp->t_bgwait, "ttybg");
  919         cv_init(&tp->t_dcdwait, "ttydcd");
  920 
  921         /* Allow drivers to use a custom mutex to lock the TTY. */
  922         if (mutex != NULL) {
  923                 tp->t_mtx = mutex;
  924         } else {
  925                 tp->t_mtx = &tp->t_mtxobj;
  926                 mtx_init(&tp->t_mtxobj, "ttymtx", NULL, MTX_DEF);
  927         }
  928 
  929         knlist_init_mtx(&tp->t_inpoll.si_note, tp->t_mtx);
  930         knlist_init_mtx(&tp->t_outpoll.si_note, tp->t_mtx);
  931 
  932         sx_xlock(&tty_list_sx);
  933         TAILQ_INSERT_TAIL(&tty_list, tp, t_list);
  934         tty_list_count++;
  935         sx_xunlock(&tty_list_sx);
  936 
  937         return (tp);
  938 }
  939 
  940 static void
  941 tty_dealloc(void *arg)
  942 {
  943         struct tty *tp = arg;
  944 
  945         sx_xlock(&tty_list_sx);
  946         TAILQ_REMOVE(&tty_list, tp, t_list);
  947         tty_list_count--;
  948         sx_xunlock(&tty_list_sx);
  949 
  950         /* Make sure we haven't leaked buffers. */
  951         MPASS(ttyinq_getsize(&tp->t_inq) == 0);
  952         MPASS(ttyoutq_getsize(&tp->t_outq) == 0);
  953 
  954         knlist_destroy(&tp->t_inpoll.si_note);
  955         knlist_destroy(&tp->t_outpoll.si_note);
  956 
  957         cv_destroy(&tp->t_inwait);
  958         cv_destroy(&tp->t_outwait);
  959         cv_destroy(&tp->t_bgwait);
  960         cv_destroy(&tp->t_dcdwait);
  961         cv_destroy(&tp->t_outserwait);
  962 
  963         if (tp->t_mtx == &tp->t_mtxobj)
  964                 mtx_destroy(&tp->t_mtxobj);
  965         ttydevsw_free(tp);
  966         free(tp, M_TTY);
  967 }
  968 
  969 static void
  970 tty_rel_free(struct tty *tp)
  971 {
  972         struct cdev *dev;
  973 
  974         tty_lock_assert(tp, MA_OWNED);
  975 
  976 #define TF_ACTIVITY     (TF_GONE|TF_OPENED|TF_HOOK|TF_OPENCLOSE)
  977         if (tp->t_sessioncnt != 0 || (tp->t_flags & TF_ACTIVITY) != TF_GONE) {
  978                 /* TTY is still in use. */
  979                 tty_unlock(tp);
  980                 return;
  981         }
  982 
  983         /* TTY can be deallocated. */
  984         dev = tp->t_dev;
  985         tp->t_dev = NULL;
  986         tty_unlock(tp);
  987 
  988         destroy_dev_sched_cb(dev, tty_dealloc, tp);
  989 }
  990 
  991 void
  992 tty_rel_pgrp(struct tty *tp, struct pgrp *pg)
  993 {
  994         MPASS(tp->t_sessioncnt > 0);
  995         tty_lock_assert(tp, MA_OWNED);
  996 
  997         if (tp->t_pgrp == pg)
  998                 tp->t_pgrp = NULL;
  999         
 1000         tty_unlock(tp);
 1001 }
 1002 
 1003 void
 1004 tty_rel_sess(struct tty *tp, struct session *sess)
 1005 {
 1006         MPASS(tp->t_sessioncnt > 0);
 1007 
 1008         /* Current session has left. */
 1009         if (tp->t_session == sess) {
 1010                 tp->t_session = NULL;
 1011                 MPASS(tp->t_pgrp == NULL);
 1012         }
 1013         tp->t_sessioncnt--;
 1014         tty_rel_free(tp);
 1015 }
 1016 
 1017 void
 1018 tty_rel_gone(struct tty *tp)
 1019 {
 1020         MPASS(!tty_gone(tp));
 1021 
 1022         /* Simulate carrier removal. */
 1023         ttydisc_modem(tp, 0);
 1024 
 1025         /* Wake up all blocked threads. */
 1026         tty_wakeup(tp, FREAD|FWRITE);
 1027         cv_broadcast(&tp->t_bgwait);
 1028         cv_broadcast(&tp->t_dcdwait);
 1029 
 1030         tp->t_flags |= TF_GONE;
 1031         tty_rel_free(tp);
 1032 }
 1033 
 1034 /*
 1035  * Exposing information about current TTY's through sysctl
 1036  */
 1037 
 1038 static void
 1039 tty_to_xtty(struct tty *tp, struct xtty *xt)
 1040 {
 1041         tty_lock_assert(tp, MA_OWNED);
 1042 
 1043         xt->xt_size = sizeof(struct xtty);
 1044         xt->xt_insize = ttyinq_getsize(&tp->t_inq);
 1045         xt->xt_incc = ttyinq_bytescanonicalized(&tp->t_inq);
 1046         xt->xt_inlc = ttyinq_bytesline(&tp->t_inq);
 1047         xt->xt_inlow = tp->t_inlow;
 1048         xt->xt_outsize = ttyoutq_getsize(&tp->t_outq);
 1049         xt->xt_outcc = ttyoutq_bytesused(&tp->t_outq);
 1050         xt->xt_outlow = tp->t_outlow;
 1051         xt->xt_column = tp->t_column;
 1052         xt->xt_pgid = tp->t_pgrp ? tp->t_pgrp->pg_id : 0;
 1053         xt->xt_sid = tp->t_session ? tp->t_session->s_sid : 0;
 1054         xt->xt_flags = tp->t_flags;
 1055         xt->xt_dev = tp->t_dev ? dev2udev(tp->t_dev) : NODEV;
 1056 }
 1057 
 1058 static int
 1059 sysctl_kern_ttys(SYSCTL_HANDLER_ARGS)
 1060 {
 1061         unsigned long lsize;
 1062         struct xtty *xtlist, *xt;
 1063         struct tty *tp;
 1064         int error;
 1065 
 1066         sx_slock(&tty_list_sx);
 1067         lsize = tty_list_count * sizeof(struct xtty);
 1068         if (lsize == 0) {
 1069                 sx_sunlock(&tty_list_sx);
 1070                 return (0);
 1071         }
 1072 
 1073         xtlist = xt = malloc(lsize, M_TTY, M_WAITOK);
 1074 
 1075         TAILQ_FOREACH(tp, &tty_list, t_list) {
 1076                 tty_lock(tp);
 1077                 tty_to_xtty(tp, xt);
 1078                 tty_unlock(tp);
 1079                 xt++;
 1080         }
 1081         sx_sunlock(&tty_list_sx);
 1082 
 1083         error = SYSCTL_OUT(req, xtlist, lsize);
 1084         free(xtlist, M_TTY);
 1085         return (error);
 1086 }
 1087 
 1088 SYSCTL_PROC(_kern, OID_AUTO, ttys, CTLTYPE_OPAQUE|CTLFLAG_RD|CTLFLAG_MPSAFE,
 1089         0, 0, sysctl_kern_ttys, "S,xtty", "List of TTYs");
 1090 
 1091 /*
 1092  * Device node creation. Device has been set up, now we can expose it to
 1093  * the user.
 1094  */
 1095 
 1096 void
 1097 tty_makedev(struct tty *tp, struct ucred *cred, const char *fmt, ...)
 1098 {
 1099         va_list ap;
 1100         struct cdev *dev;
 1101         const char *prefix = "tty";
 1102         char name[SPECNAMELEN - 3]; /* for "tty" and "cua". */
 1103         uid_t uid;
 1104         gid_t gid;
 1105         mode_t mode;
 1106 
 1107         /* Remove "tty" prefix from devices like PTY's. */
 1108         if (tp->t_flags & TF_NOPREFIX)
 1109                 prefix = "";
 1110 
 1111         va_start(ap, fmt);
 1112         vsnrprintf(name, sizeof name, 32, fmt, ap);
 1113         va_end(ap);
 1114 
 1115         if (cred == NULL) {
 1116                 /* System device. */
 1117                 uid = UID_ROOT;
 1118                 gid = GID_WHEEL;
 1119                 mode = S_IRUSR|S_IWUSR;
 1120         } else {
 1121                 /* User device. */
 1122                 uid = cred->cr_ruid;
 1123                 gid = GID_TTY;
 1124                 mode = S_IRUSR|S_IWUSR|S_IWGRP;
 1125         }
 1126 
 1127         /* Master call-in device. */
 1128         dev = make_dev_cred(&ttydev_cdevsw, 0, cred,
 1129             uid, gid, mode, "%s%s", prefix, name);
 1130         dev->si_drv1 = tp;
 1131         tp->t_dev = dev;
 1132 
 1133         /* Slave call-in devices. */
 1134         if (tp->t_flags & TF_INITLOCK) {
 1135                 dev = make_dev_cred(&ttyil_cdevsw, 0, cred,
 1136                     uid, gid, mode, "%s%s.init", prefix, name);
 1137                 dev_depends(tp->t_dev, dev);
 1138                 dev->si_drv1 = tp;
 1139                 dev->si_drv2 = &tp->t_termios_init_in;
 1140 
 1141                 dev = make_dev_cred(&ttyil_cdevsw, 0, cred,
 1142                     uid, gid, mode, "%s%s.lock", prefix, name);
 1143                 dev_depends(tp->t_dev, dev);
 1144                 dev->si_drv1 = tp;
 1145                 dev->si_drv2 = &tp->t_termios_lock_in;
 1146         }
 1147 
 1148         /* Call-out devices. */
 1149         if (tp->t_flags & TF_CALLOUT) {
 1150                 dev = make_dev_cred(&ttydev_cdevsw, 0, cred,
 1151                     UID_UUCP, GID_DIALER, 0660, "cua%s", name);
 1152                 dev_depends(tp->t_dev, dev);
 1153                 dev->si_drv1 = tp;
 1154 
 1155                 /* Slave call-out devices. */
 1156                 if (tp->t_flags & TF_INITLOCK) {
 1157                         dev = make_dev_cred(&ttyil_cdevsw, 0, cred,
 1158                             UID_UUCP, GID_DIALER, 0660, "cua%s.init", name);
 1159                         dev_depends(tp->t_dev, dev);
 1160                         dev->si_drv1 = tp;
 1161                         dev->si_drv2 = &tp->t_termios_init_out;
 1162 
 1163                         dev = make_dev_cred(&ttyil_cdevsw, 0, cred,
 1164                             UID_UUCP, GID_DIALER, 0660, "cua%s.lock", name);
 1165                         dev_depends(tp->t_dev, dev);
 1166                         dev->si_drv1 = tp;
 1167                         dev->si_drv2 = &tp->t_termios_lock_out;
 1168                 }
 1169         }
 1170 }
 1171 
 1172 /*
 1173  * Signalling processes.
 1174  */
 1175 
 1176 void
 1177 tty_signal_sessleader(struct tty *tp, int sig)
 1178 {
 1179         struct proc *p;
 1180 
 1181         tty_lock_assert(tp, MA_OWNED);
 1182         MPASS(sig >= 1 && sig < NSIG);
 1183 
 1184         /* Make signals start output again. */
 1185         tp->t_flags &= ~TF_STOPPED;
 1186         
 1187         if (tp->t_session != NULL && tp->t_session->s_leader != NULL) {
 1188                 p = tp->t_session->s_leader;
 1189                 PROC_LOCK(p);
 1190                 psignal(p, sig);
 1191                 PROC_UNLOCK(p);
 1192         }
 1193 }
 1194 
 1195 void
 1196 tty_signal_pgrp(struct tty *tp, int sig)
 1197 {
 1198         tty_lock_assert(tp, MA_OWNED);
 1199         MPASS(sig >= 1 && sig < NSIG);
 1200 
 1201         /* Make signals start output again. */
 1202         tp->t_flags &= ~TF_STOPPED;
 1203 
 1204         if (sig == SIGINFO && !(tp->t_termios.c_lflag & NOKERNINFO))
 1205                 tty_info(tp);
 1206         if (tp->t_pgrp != NULL) {
 1207                 PGRP_LOCK(tp->t_pgrp);
 1208                 pgsignal(tp->t_pgrp, sig, 1);
 1209                 PGRP_UNLOCK(tp->t_pgrp);
 1210         }
 1211 }
 1212 
 1213 void
 1214 tty_wakeup(struct tty *tp, int flags)
 1215 {
 1216         if (tp->t_flags & TF_ASYNC && tp->t_sigio != NULL)
 1217                 pgsigio(&tp->t_sigio, SIGIO, (tp->t_session != NULL));
 1218 
 1219         if (flags & FWRITE) {
 1220                 cv_broadcast(&tp->t_outwait);
 1221                 selwakeup(&tp->t_outpoll);
 1222                 KNOTE_LOCKED(&tp->t_outpoll.si_note, 0);
 1223         }
 1224         if (flags & FREAD) {
 1225                 cv_broadcast(&tp->t_inwait);
 1226                 selwakeup(&tp->t_inpoll);
 1227                 KNOTE_LOCKED(&tp->t_inpoll.si_note, 0);
 1228         }
 1229 }
 1230 
 1231 int
 1232 tty_wait(struct tty *tp, struct cv *cv)
 1233 {
 1234         int error;
 1235         int revokecnt = tp->t_revokecnt;
 1236 
 1237         tty_lock_assert(tp, MA_OWNED|MA_NOTRECURSED);
 1238         MPASS(!tty_gone(tp));
 1239 
 1240         error = cv_wait_sig(cv, tp->t_mtx);
 1241 
 1242         /* Restart the system call when we may have been revoked. */
 1243         if (tp->t_revokecnt != revokecnt)
 1244                 return (ERESTART);
 1245         
 1246         /* Bail out when the device slipped away. */
 1247         if (tty_gone(tp))
 1248                 return (ENXIO);
 1249 
 1250         return (error);
 1251 }
 1252 
 1253 int
 1254 tty_timedwait(struct tty *tp, struct cv *cv, int hz)
 1255 {
 1256         int error;
 1257         int revokecnt = tp->t_revokecnt;
 1258 
 1259         tty_lock_assert(tp, MA_OWNED|MA_NOTRECURSED);
 1260         MPASS(!tty_gone(tp));
 1261 
 1262         error = cv_timedwait_sig(cv, tp->t_mtx, hz);
 1263 
 1264         /* Restart the system call when we may have been revoked. */
 1265         if (tp->t_revokecnt != revokecnt)
 1266                 return (ERESTART);
 1267         
 1268         /* Bail out when the device slipped away. */
 1269         if (tty_gone(tp))
 1270                 return (ENXIO);
 1271 
 1272         return (error);
 1273 }
 1274 
 1275 void
 1276 tty_flush(struct tty *tp, int flags)
 1277 {
 1278         if (flags & FWRITE) {
 1279                 tp->t_flags &= ~TF_HIWAT_OUT;
 1280                 ttyoutq_flush(&tp->t_outq);
 1281                 tty_wakeup(tp, FWRITE);
 1282                 ttydevsw_pktnotify(tp, TIOCPKT_FLUSHWRITE);
 1283         }
 1284         if (flags & FREAD) {
 1285                 tty_hiwat_in_unblock(tp);
 1286                 ttyinq_flush(&tp->t_inq);
 1287                 ttydevsw_inwakeup(tp);
 1288                 ttydevsw_pktnotify(tp, TIOCPKT_FLUSHREAD);
 1289         }
 1290 }
 1291 
 1292 static int
 1293 tty_generic_ioctl(struct tty *tp, u_long cmd, void *data, struct thread *td)
 1294 {
 1295         int error;
 1296 
 1297         switch (cmd) {
 1298         /*
 1299          * Modem commands.
 1300          * The SER_* and TIOCM_* flags are the same, but one bit
 1301          * shifted. I don't know why.
 1302          */
 1303         case TIOCSDTR:
 1304                 ttydevsw_modem(tp, SER_DTR, 0);
 1305                 return (0);
 1306         case TIOCCDTR:
 1307                 ttydevsw_modem(tp, 0, SER_DTR);
 1308                 return (0);
 1309         case TIOCMSET: {
 1310                 int bits = *(int *)data;
 1311                 ttydevsw_modem(tp,
 1312                     (bits & (TIOCM_DTR | TIOCM_RTS)) >> 1,
 1313                     ((~bits) & (TIOCM_DTR | TIOCM_RTS)) >> 1);
 1314                 return (0);
 1315         }
 1316         case TIOCMBIS: {
 1317                 int bits = *(int *)data;
 1318                 ttydevsw_modem(tp, (bits & (TIOCM_DTR | TIOCM_RTS)) >> 1, 0);
 1319                 return (0);
 1320         }
 1321         case TIOCMBIC: {
 1322                 int bits = *(int *)data;
 1323                 ttydevsw_modem(tp, 0, (bits & (TIOCM_DTR | TIOCM_RTS)) >> 1);
 1324                 return (0);
 1325         }
 1326         case TIOCMGET:
 1327                 *(int *)data = TIOCM_LE + (ttydevsw_modem(tp, 0, 0) << 1);
 1328                 return (0);
 1329 
 1330         case FIOASYNC:
 1331                 if (*(int *)data)
 1332                         tp->t_flags |= TF_ASYNC;
 1333                 else
 1334                         tp->t_flags &= ~TF_ASYNC;
 1335                 return (0);
 1336         case FIONBIO:
 1337                 /* This device supports non-blocking operation. */
 1338                 return (0);
 1339         case FIONREAD:
 1340                 *(int *)data = ttyinq_bytescanonicalized(&tp->t_inq);
 1341                 return (0);
 1342         case FIONWRITE:
 1343         case TIOCOUTQ:
 1344                 *(int *)data = ttyoutq_bytesused(&tp->t_outq);
 1345                 return (0);
 1346         case FIOSETOWN:
 1347                 if (tp->t_session != NULL && !tty_is_ctty(tp, td->td_proc))
 1348                         /* Not allowed to set ownership. */
 1349                         return (ENOTTY);
 1350 
 1351                 /* Temporarily unlock the TTY to set ownership. */
 1352                 tty_unlock(tp);
 1353                 error = fsetown(*(int *)data, &tp->t_sigio);
 1354                 tty_lock(tp);
 1355                 return (error);
 1356         case FIOGETOWN:
 1357                 if (tp->t_session != NULL && !tty_is_ctty(tp, td->td_proc))
 1358                         /* Not allowed to set ownership. */
 1359                         return (ENOTTY);
 1360 
 1361                 /* Get ownership. */
 1362                 *(int *)data = fgetown(&tp->t_sigio);
 1363                 return (0);
 1364         case TIOCGETA:
 1365                 /* Obtain terminal flags through tcgetattr(). */
 1366                 *(struct termios*)data = tp->t_termios;
 1367                 return (0);
 1368         case TIOCSETA:
 1369         case TIOCSETAW:
 1370         case TIOCSETAF: {
 1371                 struct termios *t = data;
 1372 
 1373                 /*
 1374                  * Who makes up these funny rules? According to POSIX,
 1375                  * input baud rate is set equal to the output baud rate
 1376                  * when zero.
 1377                  */
 1378                 if (t->c_ispeed == 0)
 1379                         t->c_ispeed = t->c_ospeed;
 1380 
 1381                 /* Discard any unsupported bits. */
 1382                 t->c_iflag &= TTYSUP_IFLAG;
 1383                 t->c_oflag &= TTYSUP_OFLAG;
 1384                 t->c_lflag &= TTYSUP_LFLAG;
 1385                 t->c_cflag &= TTYSUP_CFLAG;
 1386 
 1387                 /* Set terminal flags through tcsetattr(). */
 1388                 if (cmd == TIOCSETAW || cmd == TIOCSETAF) {
 1389                         error = tty_drain(tp);
 1390                         if (error)
 1391                                 return (error);
 1392                         if (cmd == TIOCSETAF)
 1393                                 tty_flush(tp, FREAD);
 1394                 }
 1395 
 1396                 /*
 1397                  * Only call param() when the flags really change.
 1398                  */
 1399                 if ((t->c_cflag & CIGNORE) == 0 &&
 1400                     (tp->t_termios.c_cflag != t->c_cflag ||
 1401                     tp->t_termios.c_ispeed != t->c_ispeed ||
 1402                     tp->t_termios.c_ospeed != t->c_ospeed)) {
 1403                         error = ttydevsw_param(tp, t);
 1404                         if (error)
 1405                                 return (error);
 1406 
 1407                         /* XXX: CLOCAL? */
 1408                         
 1409                         tp->t_termios.c_cflag = t->c_cflag & ~CIGNORE;
 1410                         tp->t_termios.c_ispeed = t->c_ispeed;
 1411                         tp->t_termios.c_ospeed = t->c_ospeed;
 1412 
 1413                         /* Baud rate has changed - update watermarks. */
 1414                         tty_watermarks(tp);
 1415                 }
 1416 
 1417                 /* Copy new non-device driver parameters. */
 1418                 tp->t_termios.c_iflag = t->c_iflag;
 1419                 tp->t_termios.c_oflag = t->c_oflag;
 1420                 tp->t_termios.c_lflag = t->c_lflag;
 1421                 memcpy(&tp->t_termios.c_cc, t->c_cc, sizeof t->c_cc);
 1422 
 1423                 ttydisc_optimize(tp);
 1424 
 1425                 if ((t->c_lflag & ICANON) == 0) {
 1426                         /*
 1427                          * When in non-canonical mode, wake up all
 1428                          * readers. Canonicalize any partial input. VMIN
 1429                          * and VTIME could also be adjusted.
 1430                          */
 1431                         ttyinq_canonicalize(&tp->t_inq);
 1432                         tty_wakeup(tp, FREAD);
 1433                 }
 1434 
 1435                 /*
 1436                  * For packet mode: notify the PTY consumer that VSTOP
 1437                  * and VSTART may have been changed.
 1438                  */
 1439                 if (tp->t_termios.c_iflag & IXON &&
 1440                     tp->t_termios.c_cc[VSTOP] == CTRL('S') &&
 1441                     tp->t_termios.c_cc[VSTART] == CTRL('Q'))
 1442                         ttydevsw_pktnotify(tp, TIOCPKT_DOSTOP);
 1443                 else
 1444                         ttydevsw_pktnotify(tp, TIOCPKT_NOSTOP);
 1445                 return (0);
 1446         }
 1447         case TIOCGETD:
 1448                 /* For compatibility - we only support TTYDISC. */
 1449                 *(int *)data = TTYDISC;
 1450                 return (0);
 1451         case TIOCGPGRP:
 1452                 if (!tty_is_ctty(tp, td->td_proc))
 1453                         return (ENOTTY);
 1454 
 1455                 if (tp->t_pgrp != NULL)
 1456                         *(int *)data = tp->t_pgrp->pg_id;
 1457                 else
 1458                         *(int *)data = NO_PID;
 1459                 return (0);
 1460         case TIOCGSID:
 1461                 if (!tty_is_ctty(tp, td->td_proc))
 1462                         return (ENOTTY);
 1463 
 1464                 MPASS(tp->t_session);
 1465                 *(int *)data = tp->t_session->s_sid;
 1466                 return (0);
 1467         case TIOCSCTTY: {
 1468                 struct proc *p = td->td_proc;
 1469 
 1470                 /* XXX: This looks awful. */
 1471                 tty_unlock(tp);
 1472                 sx_xlock(&proctree_lock);
 1473                 tty_lock(tp);
 1474 
 1475                 if (!SESS_LEADER(p)) {
 1476                         /* Only the session leader may do this. */
 1477                         sx_xunlock(&proctree_lock);
 1478                         return (EPERM);
 1479                 }
 1480 
 1481                 if (tp->t_session != NULL && tp->t_session == p->p_session) {
 1482                         /* This is already our controlling TTY. */
 1483                         sx_xunlock(&proctree_lock);
 1484                         return (0);
 1485                 }
 1486 
 1487                 if (p->p_session->s_ttyp != NULL ||
 1488                     (tp->t_session != NULL && tp->t_session->s_ttyvp != NULL &&
 1489                     tp->t_session->s_ttyvp->v_type != VBAD)) {
 1490                         /*
 1491                          * There is already a relation between a TTY and
 1492                          * a session, or the caller is not the session
 1493                          * leader.
 1494                          *
 1495                          * Allow the TTY to be stolen when the vnode is
 1496                          * invalid, but the reference to the TTY is
 1497                          * still active.  This allows immediate reuse of
 1498                          * TTYs of which the session leader has been
 1499                          * killed or the TTY revoked.
 1500                          */
 1501                         sx_xunlock(&proctree_lock);
 1502                         return (EPERM);
 1503                 }
 1504 
 1505                 /* Connect the session to the TTY. */
 1506                 tp->t_session = p->p_session;
 1507                 tp->t_session->s_ttyp = tp;
 1508                 tp->t_sessioncnt++;
 1509                 sx_xunlock(&proctree_lock);
 1510 
 1511                 /* Assign foreground process group. */
 1512                 tp->t_pgrp = p->p_pgrp;
 1513                 PROC_LOCK(p);
 1514                 p->p_flag |= P_CONTROLT;
 1515                 PROC_UNLOCK(p);
 1516 
 1517                 return (0);
 1518         }
 1519         case TIOCSPGRP: {
 1520                 struct pgrp *pg;
 1521 
 1522                 /*
 1523                  * XXX: Temporarily unlock the TTY to locate the process
 1524                  * group. This code would be lot nicer if we would ever
 1525                  * decompose proctree_lock.
 1526                  */
 1527                 tty_unlock(tp);
 1528                 sx_slock(&proctree_lock);
 1529                 pg = pgfind(*(int *)data);
 1530                 if (pg != NULL)
 1531                         PGRP_UNLOCK(pg);
 1532                 if (pg == NULL || pg->pg_session != td->td_proc->p_session) {
 1533                         sx_sunlock(&proctree_lock);
 1534                         tty_lock(tp);
 1535                         return (EPERM);
 1536                 }
 1537                 tty_lock(tp);
 1538 
 1539                 /*
 1540                  * Determine if this TTY is the controlling TTY after
 1541                  * relocking the TTY.
 1542                  */
 1543                 if (!tty_is_ctty(tp, td->td_proc)) {
 1544                         sx_sunlock(&proctree_lock);
 1545                         return (ENOTTY);
 1546                 }
 1547                 tp->t_pgrp = pg;
 1548                 sx_sunlock(&proctree_lock);
 1549 
 1550                 /* Wake up the background process groups. */
 1551                 cv_broadcast(&tp->t_bgwait);
 1552                 return (0);
 1553         }
 1554         case TIOCFLUSH: {
 1555                 int flags = *(int *)data;
 1556 
 1557                 if (flags == 0)
 1558                         flags = (FREAD|FWRITE);
 1559                 else
 1560                         flags &= (FREAD|FWRITE);
 1561                 tty_flush(tp, flags);
 1562                 return (0);
 1563         }
 1564         case TIOCDRAIN:
 1565                 /* Drain TTY output. */
 1566                 return tty_drain(tp);
 1567         case TIOCCONS:
 1568                 /* Set terminal as console TTY. */
 1569                 if (*(int *)data) {
 1570                         error = priv_check(td, PRIV_TTY_CONSOLE);
 1571                         if (error)
 1572                                 return (error);
 1573 
 1574                         /*
 1575                          * XXX: constty should really need to be locked!
 1576                          * XXX: allow disconnected constty's to be stolen!
 1577                          */
 1578 
 1579                         if (constty == tp)
 1580                                 return (0);
 1581                         if (constty != NULL)
 1582                                 return (EBUSY);
 1583 
 1584                         tty_unlock(tp);
 1585                         constty_set(tp);
 1586                         tty_lock(tp);
 1587                 } else if (constty == tp) {
 1588                         constty_clear();
 1589                 }
 1590                 return (0);
 1591         case TIOCGWINSZ:
 1592                 /* Obtain window size. */
 1593                 *(struct winsize*)data = tp->t_winsize;
 1594                 return (0);
 1595         case TIOCSWINSZ:
 1596                 /* Set window size. */
 1597                 if (bcmp(&tp->t_winsize, data, sizeof(struct winsize)) == 0)
 1598                         return (0);
 1599                 tp->t_winsize = *(struct winsize*)data;
 1600                 tty_signal_pgrp(tp, SIGWINCH);
 1601                 return (0);
 1602         case TIOCEXCL:
 1603                 tp->t_flags |= TF_EXCLUDE;
 1604                 return (0);
 1605         case TIOCNXCL:
 1606                 tp->t_flags &= ~TF_EXCLUDE;
 1607                 return (0);
 1608         case TIOCSTOP:
 1609                 tp->t_flags |= TF_STOPPED;
 1610                 ttydevsw_pktnotify(tp, TIOCPKT_STOP);
 1611                 return (0);
 1612         case TIOCSTART:
 1613                 tp->t_flags &= ~TF_STOPPED;
 1614                 ttydevsw_outwakeup(tp);
 1615                 ttydevsw_pktnotify(tp, TIOCPKT_START);
 1616                 return (0);
 1617         case TIOCSTAT:
 1618                 tty_info(tp);
 1619                 return (0);
 1620         }
 1621 
 1622 #ifdef COMPAT_43TTY
 1623         return tty_ioctl_compat(tp, cmd, data, td);
 1624 #else /* !COMPAT_43TTY */
 1625         return (ENOIOCTL);
 1626 #endif /* COMPAT_43TTY */
 1627 }
 1628 
 1629 int
 1630 tty_ioctl(struct tty *tp, u_long cmd, void *data, struct thread *td)
 1631 {
 1632         int error;
 1633 
 1634         tty_lock_assert(tp, MA_OWNED);
 1635 
 1636         if (tty_gone(tp))
 1637                 return (ENXIO);
 1638         
 1639         error = ttydevsw_ioctl(tp, cmd, data, td);
 1640         if (error == ENOIOCTL)
 1641                 error = tty_generic_ioctl(tp, cmd, data, td);
 1642 
 1643         return (error);
 1644 }
 1645 
 1646 dev_t
 1647 tty_udev(struct tty *tp)
 1648 {
 1649         if (tp->t_dev)
 1650                 return dev2udev(tp->t_dev);
 1651         else
 1652                 return NODEV;
 1653 }
 1654 
 1655 int
 1656 tty_checkoutq(struct tty *tp)
 1657 {
 1658 
 1659         /* 256 bytes should be enough to print a log message. */
 1660         return (ttyoutq_bytesleft(&tp->t_outq) >= 256);
 1661 }
 1662 
 1663 void
 1664 tty_hiwat_in_block(struct tty *tp)
 1665 {
 1666 
 1667         if ((tp->t_flags & TF_HIWAT_IN) == 0 &&
 1668             tp->t_termios.c_iflag & IXOFF &&
 1669             tp->t_termios.c_cc[VSTOP] != _POSIX_VDISABLE) {
 1670                 /*
 1671                  * Input flow control. Only enter the high watermark when we
 1672                  * can successfully store the VSTOP character.
 1673                  */
 1674                 if (ttyoutq_write_nofrag(&tp->t_outq,
 1675                     &tp->t_termios.c_cc[VSTOP], 1) == 0)
 1676                         tp->t_flags |= TF_HIWAT_IN;
 1677         } else {
 1678                 /* No input flow control. */
 1679                 tp->t_flags |= TF_HIWAT_IN;
 1680         }
 1681 }
 1682 
 1683 void
 1684 tty_hiwat_in_unblock(struct tty *tp)
 1685 {
 1686 
 1687         if (tp->t_flags & TF_HIWAT_IN &&
 1688             tp->t_termios.c_iflag & IXOFF &&
 1689             tp->t_termios.c_cc[VSTART] != _POSIX_VDISABLE) {
 1690                 /*
 1691                  * Input flow control. Only leave the high watermark when we
 1692                  * can successfully store the VSTART character.
 1693                  */
 1694                 if (ttyoutq_write_nofrag(&tp->t_outq,
 1695                     &tp->t_termios.c_cc[VSTART], 1) == 0)
 1696                         tp->t_flags &= ~TF_HIWAT_IN;
 1697         } else {
 1698                 /* No input flow control. */
 1699                 tp->t_flags &= ~TF_HIWAT_IN;
 1700         }
 1701 
 1702         if (!tty_gone(tp))
 1703                 ttydevsw_inwakeup(tp);
 1704 }
 1705 
 1706 /*
 1707  * TTY hooks interface.
 1708  */
 1709 
 1710 static int
 1711 ttyhook_defrint(struct tty *tp, char c, int flags)
 1712 {
 1713 
 1714         if (ttyhook_rint_bypass(tp, &c, 1) != 1)
 1715                 return (-1);
 1716         
 1717         return (0);
 1718 }
 1719 
 1720 int
 1721 ttyhook_register(struct tty **rtp, struct proc *p, int fd,
 1722     struct ttyhook *th, void *softc)
 1723 {
 1724         struct tty *tp;
 1725         struct file *fp;
 1726         struct cdev *dev;
 1727         struct cdevsw *cdp;
 1728         struct filedesc *fdp;
 1729         int error;
 1730 
 1731         /* Validate the file descriptor. */
 1732         if ((fdp = p->p_fd) == NULL)
 1733                 return (EBADF);
 1734 
 1735         fp = fget_unlocked(fdp, fd);
 1736         if (fp == NULL)
 1737                 return (EBADF);
 1738         if (fp->f_ops == &badfileops) {
 1739                 error = EBADF;
 1740                 goto done1;
 1741         }
 1742         
 1743         /*
 1744          * Make sure the vnode is bound to a character device.
 1745          * Unlocked check for the vnode type is ok there, because we
 1746          * only shall prevent calling devvn_refthread on the file that
 1747          * never has been opened over a character device.
 1748          */
 1749         if (fp->f_type != DTYPE_VNODE || fp->f_vnode->v_type != VCHR) {
 1750                 error = EINVAL;
 1751                 goto done1;
 1752         }
 1753 
 1754         /* Make sure it is a TTY. */
 1755         cdp = devvn_refthread(fp->f_vnode, &dev);
 1756         if (cdp == NULL) {
 1757                 error = ENXIO;
 1758                 goto done1;
 1759         }
 1760         if (dev != fp->f_data) {
 1761                 error = ENXIO;
 1762                 goto done2;
 1763         }
 1764         if (cdp != &ttydev_cdevsw) {
 1765                 error = ENOTTY;
 1766                 goto done2;
 1767         }
 1768         tp = dev->si_drv1;
 1769 
 1770         /* Try to attach the hook to the TTY. */
 1771         error = EBUSY;
 1772         tty_lock(tp);
 1773         MPASS((tp->t_hook == NULL) == ((tp->t_flags & TF_HOOK) == 0));
 1774         if (tp->t_flags & TF_HOOK)
 1775                 goto done3;
 1776 
 1777         tp->t_flags |= TF_HOOK;
 1778         tp->t_hook = th;
 1779         tp->t_hooksoftc = softc;
 1780         *rtp = tp;
 1781         error = 0;
 1782 
 1783         /* Maybe we can switch into bypass mode now. */
 1784         ttydisc_optimize(tp);
 1785 
 1786         /* Silently convert rint() calls to rint_bypass() when possible. */
 1787         if (!ttyhook_hashook(tp, rint) && ttyhook_hashook(tp, rint_bypass))
 1788                 th->th_rint = ttyhook_defrint;
 1789 
 1790 done3:  tty_unlock(tp);
 1791 done2:  dev_relthread(dev);
 1792 done1:  fdrop(fp, curthread);
 1793         return (error);
 1794 }
 1795 
 1796 void
 1797 ttyhook_unregister(struct tty *tp)
 1798 {
 1799 
 1800         tty_lock_assert(tp, MA_OWNED);
 1801         MPASS(tp->t_flags & TF_HOOK);
 1802 
 1803         /* Disconnect the hook. */
 1804         tp->t_flags &= ~TF_HOOK;
 1805         tp->t_hook = NULL;
 1806 
 1807         /* Maybe we need to leave bypass mode. */
 1808         ttydisc_optimize(tp);
 1809 
 1810         /* Maybe deallocate the TTY as well. */
 1811         tty_rel_free(tp);
 1812 }
 1813 
 1814 /*
 1815  * /dev/console handling.
 1816  */
 1817 
 1818 static int
 1819 ttyconsdev_open(struct cdev *dev, int oflags, int devtype, struct thread *td)
 1820 {
 1821         struct tty *tp;
 1822 
 1823         /* System has no console device. */
 1824         if (dev_console_filename == NULL)
 1825                 return (ENXIO);
 1826 
 1827         /* Look up corresponding TTY by device name. */
 1828         sx_slock(&tty_list_sx);
 1829         TAILQ_FOREACH(tp, &tty_list, t_list) {
 1830                 if (strcmp(dev_console_filename, tty_devname(tp)) == 0) {
 1831                         dev_console->si_drv1 = tp;
 1832                         break;
 1833                 }
 1834         }
 1835         sx_sunlock(&tty_list_sx);
 1836 
 1837         /* System console has no TTY associated. */
 1838         if (dev_console->si_drv1 == NULL)
 1839                 return (ENXIO);
 1840         
 1841         return (ttydev_open(dev, oflags, devtype, td));
 1842 }
 1843 
 1844 static int
 1845 ttyconsdev_write(struct cdev *dev, struct uio *uio, int ioflag)
 1846 {
 1847 
 1848         log_console(uio);
 1849 
 1850         return (ttydev_write(dev, uio, ioflag));
 1851 }
 1852 
 1853 /*
 1854  * /dev/console is a little different than normal TTY's.  When opened,
 1855  * it determines which TTY to use.  When data gets written to it, it
 1856  * will be logged in the kernel message buffer.
 1857  */
 1858 static struct cdevsw ttyconsdev_cdevsw = {
 1859         .d_version      = D_VERSION,
 1860         .d_open         = ttyconsdev_open,
 1861         .d_close        = ttydev_close,
 1862         .d_read         = ttydev_read,
 1863         .d_write        = ttyconsdev_write,
 1864         .d_ioctl        = ttydev_ioctl,
 1865         .d_kqfilter     = ttydev_kqfilter,
 1866         .d_poll         = ttydev_poll,
 1867         .d_mmap         = ttydev_mmap,
 1868         .d_name         = "ttyconsdev",
 1869         .d_flags        = D_TTY,
 1870 };
 1871 
 1872 static void
 1873 ttyconsdev_init(void *unused)
 1874 {
 1875 
 1876         dev_console = make_dev(&ttyconsdev_cdevsw, 0, UID_ROOT, GID_WHEEL,
 1877             0600, "console");
 1878 }
 1879 
 1880 SYSINIT(tty, SI_SUB_DRIVERS, SI_ORDER_FIRST, ttyconsdev_init, NULL);
 1881 
 1882 void
 1883 ttyconsdev_select(const char *name)
 1884 {
 1885 
 1886         dev_console_filename = name;
 1887 }
 1888 
 1889 /*
 1890  * Debugging routines.
 1891  */
 1892 
 1893 #include "opt_ddb.h"
 1894 #ifdef DDB
 1895 #include <ddb/ddb.h>
 1896 #include <ddb/db_sym.h>
 1897 
 1898 static struct {
 1899         int flag;
 1900         char val;
 1901 } ttystates[] = {
 1902 #if 0
 1903         { TF_NOPREFIX,          'N' },
 1904 #endif
 1905         { TF_INITLOCK,          'I' },
 1906         { TF_CALLOUT,           'C' },
 1907 
 1908         /* Keep these together -> 'Oi' and 'Oo'. */
 1909         { TF_OPENED,            'O' },
 1910         { TF_OPENED_IN,         'i' },
 1911         { TF_OPENED_OUT,        'o' },
 1912         { TF_OPENED_CONS,       'c' },
 1913 
 1914         { TF_GONE,              'G' },
 1915         { TF_OPENCLOSE,         'B' },
 1916         { TF_ASYNC,             'Y' },
 1917         { TF_LITERAL,           'L' },
 1918 
 1919         /* Keep these together -> 'Hi' and 'Ho'. */
 1920         { TF_HIWAT,             'H' },
 1921         { TF_HIWAT_IN,          'i' },
 1922         { TF_HIWAT_OUT,         'o' },
 1923 
 1924         { TF_STOPPED,           'S' },
 1925         { TF_EXCLUDE,           'X' },
 1926         { TF_BYPASS,            'l' },
 1927         { TF_ZOMBIE,            'Z' },
 1928         { TF_HOOK,              's' },
 1929 
 1930         /* Keep these together -> 'bi' and 'bo'. */
 1931         { TF_BUSY,              'b' },
 1932         { TF_BUSY_IN,           'i' },
 1933         { TF_BUSY_OUT,          'o' },
 1934 
 1935         { 0,                    '\0'},
 1936 };
 1937 
 1938 #define TTY_FLAG_BITS \
 1939         "\2\1NOPREFIX\2INITLOCK\3CALLOUT\4OPENED_IN\5OPENED_OUT\6GONE" \
 1940         "\7OPENCLOSE\10ASYNC\11LITERAL\12HIWAT_IN\13HIWAT_OUT\14STOPPED" \
 1941         "\15EXCLUDE\16BYPASS\17ZOMBIE\20HOOK"
 1942 
 1943 #define DB_PRINTSYM(name, addr) \
 1944         db_printf("%s  " #name ": ", sep); \
 1945         db_printsym((db_addr_t) addr, DB_STGY_ANY); \
 1946         db_printf("\n");
 1947 
 1948 static void
 1949 _db_show_devsw(const char *sep, const struct ttydevsw *tsw)
 1950 {
 1951         db_printf("%sdevsw: ", sep);
 1952         db_printsym((db_addr_t)tsw, DB_STGY_ANY);
 1953         db_printf(" (%p)\n", tsw);
 1954         DB_PRINTSYM(open, tsw->tsw_open);
 1955         DB_PRINTSYM(close, tsw->tsw_close);
 1956         DB_PRINTSYM(outwakeup, tsw->tsw_outwakeup);
 1957         DB_PRINTSYM(inwakeup, tsw->tsw_inwakeup);
 1958         DB_PRINTSYM(ioctl, tsw->tsw_ioctl);
 1959         DB_PRINTSYM(param, tsw->tsw_param);
 1960         DB_PRINTSYM(modem, tsw->tsw_modem);
 1961         DB_PRINTSYM(mmap, tsw->tsw_mmap);
 1962         DB_PRINTSYM(pktnotify, tsw->tsw_pktnotify);
 1963         DB_PRINTSYM(free, tsw->tsw_free);
 1964 }
 1965 static void
 1966 _db_show_hooks(const char *sep, const struct ttyhook *th)
 1967 {
 1968         db_printf("%shook: ", sep);
 1969         db_printsym((db_addr_t)th, DB_STGY_ANY);
 1970         db_printf(" (%p)\n", th);
 1971         if (th == NULL)
 1972                 return;
 1973         DB_PRINTSYM(rint, th->th_rint);
 1974         DB_PRINTSYM(rint_bypass, th->th_rint_bypass);
 1975         DB_PRINTSYM(rint_done, th->th_rint_done);
 1976         DB_PRINTSYM(rint_poll, th->th_rint_poll);
 1977         DB_PRINTSYM(getc_inject, th->th_getc_inject);
 1978         DB_PRINTSYM(getc_capture, th->th_getc_capture);
 1979         DB_PRINTSYM(getc_poll, th->th_getc_poll);
 1980         DB_PRINTSYM(close, th->th_close);
 1981 }
 1982 
 1983 static void
 1984 _db_show_termios(const char *name, const struct termios *t)
 1985 {
 1986 
 1987         db_printf("%s: iflag 0x%x oflag 0x%x cflag 0x%x "
 1988             "lflag 0x%x ispeed %u ospeed %u\n", name,
 1989             t->c_iflag, t->c_oflag, t->c_cflag, t->c_lflag,
 1990             t->c_ispeed, t->c_ospeed);
 1991 }
 1992 
 1993 /* DDB command to show TTY statistics. */
 1994 DB_SHOW_COMMAND(tty, db_show_tty)
 1995 {
 1996         struct tty *tp;
 1997 
 1998         if (!have_addr) {
 1999                 db_printf("usage: show tty <addr>\n");
 2000                 return;
 2001         }
 2002         tp = (struct tty *)addr;
 2003 
 2004         db_printf("0x%p: %s\n", tp, tty_devname(tp));
 2005         db_printf("\tmtx: %p\n", tp->t_mtx);
 2006         db_printf("\tflags: %b\n", tp->t_flags, TTY_FLAG_BITS);
 2007         db_printf("\trevokecnt: %u\n", tp->t_revokecnt);
 2008 
 2009         /* Buffering mechanisms. */
 2010         db_printf("\tinq: %p begin %u linestart %u reprint %u end %u "
 2011             "nblocks %u quota %u\n", &tp->t_inq, tp->t_inq.ti_begin,
 2012             tp->t_inq.ti_linestart, tp->t_inq.ti_reprint, tp->t_inq.ti_end,
 2013             tp->t_inq.ti_nblocks, tp->t_inq.ti_quota);
 2014         db_printf("\toutq: %p begin %u end %u nblocks %u quota %u\n",
 2015             &tp->t_outq, tp->t_outq.to_begin, tp->t_outq.to_end,
 2016             tp->t_outq.to_nblocks, tp->t_outq.to_quota);
 2017         db_printf("\tinlow: %zu\n", tp->t_inlow);
 2018         db_printf("\toutlow: %zu\n", tp->t_outlow);
 2019         _db_show_termios("\ttermios", &tp->t_termios);
 2020         db_printf("\twinsize: row %u col %u xpixel %u ypixel %u\n",
 2021             tp->t_winsize.ws_row, tp->t_winsize.ws_col,
 2022             tp->t_winsize.ws_xpixel, tp->t_winsize.ws_ypixel);
 2023         db_printf("\tcolumn: %u\n", tp->t_column);
 2024         db_printf("\twritepos: %u\n", tp->t_writepos);
 2025         db_printf("\tcompatflags: 0x%x\n", tp->t_compatflags);
 2026 
 2027         /* Init/lock-state devices. */
 2028         _db_show_termios("\ttermios_init_in", &tp->t_termios_init_in);
 2029         _db_show_termios("\ttermios_init_out", &tp->t_termios_init_out);
 2030         _db_show_termios("\ttermios_lock_in", &tp->t_termios_lock_in);
 2031         _db_show_termios("\ttermios_lock_out", &tp->t_termios_lock_out);
 2032 
 2033         /* Hooks */
 2034         _db_show_devsw("\t", tp->t_devsw);
 2035         _db_show_hooks("\t", tp->t_hook);
 2036 
 2037         /* Process info. */
 2038         db_printf("\tpgrp: %p gid %d jobc %d\n", tp->t_pgrp,
 2039             tp->t_pgrp ? tp->t_pgrp->pg_id : 0,
 2040             tp->t_pgrp ? tp->t_pgrp->pg_jobc : 0);
 2041         db_printf("\tsession: %p", tp->t_session);
 2042         if (tp->t_session != NULL)
 2043             db_printf(" count %u leader %p tty %p sid %d login %s",
 2044                 tp->t_session->s_count, tp->t_session->s_leader,
 2045                 tp->t_session->s_ttyp, tp->t_session->s_sid,
 2046                 tp->t_session->s_login);
 2047         db_printf("\n");
 2048         db_printf("\tsessioncnt: %u\n", tp->t_sessioncnt);
 2049         db_printf("\tdevswsoftc: %p\n", tp->t_devswsoftc);
 2050         db_printf("\thooksoftc: %p\n", tp->t_hooksoftc);
 2051         db_printf("\tdev: %p\n", tp->t_dev);
 2052 }
 2053 
 2054 /* DDB command to list TTYs. */
 2055 DB_SHOW_ALL_COMMAND(ttys, db_show_all_ttys)
 2056 {
 2057         struct tty *tp;
 2058         size_t isiz, osiz;
 2059         int i, j;
 2060 
 2061         /* Make the output look like `pstat -t'. */
 2062         db_printf("PTR        ");
 2063 #if defined(__LP64__)
 2064         db_printf("        ");
 2065 #endif
 2066         db_printf("      LINE   INQ  CAN  LIN  LOW  OUTQ  USE  LOW   "
 2067             "COL  SESS  PGID STATE\n");
 2068 
 2069         TAILQ_FOREACH(tp, &tty_list, t_list) {
 2070                 isiz = tp->t_inq.ti_nblocks * TTYINQ_DATASIZE;
 2071                 osiz = tp->t_outq.to_nblocks * TTYOUTQ_DATASIZE;
 2072 
 2073                 db_printf("%p %10s %5zu %4u %4u %4zu %5zu %4u %4zu %5u %5d %5d ",
 2074                     tp,
 2075                     tty_devname(tp),
 2076                     isiz,
 2077                     tp->t_inq.ti_linestart - tp->t_inq.ti_begin,
 2078                     tp->t_inq.ti_end - tp->t_inq.ti_linestart,
 2079                     isiz - tp->t_inlow,
 2080                     osiz,
 2081                     tp->t_outq.to_end - tp->t_outq.to_begin,
 2082                     osiz - tp->t_outlow,
 2083                     MIN(tp->t_column, 99999),
 2084                     tp->t_session ? tp->t_session->s_sid : 0,
 2085                     tp->t_pgrp ? tp->t_pgrp->pg_id : 0);
 2086 
 2087                 /* Flag bits. */
 2088                 for (i = j = 0; ttystates[i].flag; i++)
 2089                         if (tp->t_flags & ttystates[i].flag) {
 2090                                 db_printf("%c", ttystates[i].val);
 2091                                 j++;
 2092                         }
 2093                 if (j == 0)
 2094                         db_printf("-");
 2095                 db_printf("\n");
 2096         }
 2097 }
 2098 #endif /* DDB */

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