sys/kern/tty.c

   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("$FreeBSD$");
  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         "\20\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 */