sys/kern/tty_pty.c

   1 /*
   2  * Copyright (c) 1982, 1986, 1989, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by the University of
  16  *      California, Berkeley and its contributors.
  17  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  *
  33  *      @(#)tty_pty.c   8.4 (Berkeley) 2/20/95
  34  * $FreeBSD: src/sys/kern/tty_pty.c,v 1.74.2.4 2002/02/20 19:58:13 dillon Exp $
  35  * $DragonFly: src/sys/kern/tty_pty.c,v 1.21 2008/08/13 10:29:38 swildner Exp $
  36  */
  37
  38 /*
  39  * Pseudo-teletype Driver
  40  * (Actually two drivers, requiring two dev_ops structures)
  41  */
  42 #include "use_pty.h"            /* XXX */
  43 #include "opt_compat.h"
  44
  45 #include <sys/param.h>
  46 #include <sys/systm.h>
  47 #if defined(COMPAT_43) || defined(COMPAT_SUNOS)
  48 #include <sys/ioctl_compat.h>
  49 #endif
  50 #include <sys/proc.h>
  51 #include <sys/priv.h>
  52 #include <sys/tty.h>
  53 #include <sys/conf.h>
  54 #include <sys/fcntl.h>
  55 #include <sys/poll.h>
  56 #include <sys/kernel.h>
  57 #include <sys/vnode.h>
  58 #include <sys/signalvar.h>
  59 #include <sys/malloc.h>
  60 #include <sys/device.h>
  61 #include <sys/thread2.h>
  62
  63 MALLOC_DEFINE(M_PTY, "ptys", "pty data structures");
  64
  65 static void ptsstart (struct tty *tp);
  66 static void ptsstop (struct tty *tp, int rw);
  67 static void ptcwakeup (struct tty *tp, int flag);
  68 static void ptyinit (int n);
  69
  70 static  d_open_t        ptsopen;
  71 static  d_close_t       ptsclose;
  72 static  d_read_t        ptsread;
  73 static  d_write_t       ptswrite;
  74 static  d_ioctl_t       ptyioctl;
  75 static  d_open_t        ptcopen;
  76 static  d_close_t       ptcclose;
  77 static  d_read_t        ptcread;
  78 static  d_write_t       ptcwrite;
  79 static  d_poll_t        ptcpoll;
  80
  81 #define CDEV_MAJOR_S    5
  82 static struct dev_ops pts_ops = {
  83         { "pts", CDEV_MAJOR_S, D_TTY | D_KQFILTER },
  84         .d_open =       ptsopen,
  85         .d_close =      ptsclose,
  86         .d_read =       ptsread,
  87         .d_write =      ptswrite,
  88         .d_ioctl =      ptyioctl,
  89         .d_poll =       ttypoll,
  90         .d_kqfilter =   ttykqfilter
  91 };
  92
  93 #define CDEV_MAJOR_C    6
  94 static struct dev_ops ptc_ops = {
  95         { "ptc", CDEV_MAJOR_C, D_TTY | D_KQFILTER | D_MASTER },
  96         .d_open =       ptcopen,
  97         .d_close =      ptcclose,
  98         .d_read =       ptcread,
  99         .d_write =      ptcwrite,
 100         .d_ioctl =      ptyioctl,
 101         .d_poll =       ptcpoll,
 102         .d_kqfilter =   ttykqfilter
 103 };
 104
 105 #define BUFSIZ 100              /* Chunk size iomoved to/from user */
 106
 107 struct  pt_ioctl {
 108         int     pt_flags;
 109         struct  selinfo pt_selr, pt_selw;
 110         u_char  pt_send;
 111         u_char  pt_ucntl;
 112         struct tty pt_tty;
 113         cdev_t  devs, devc;
 114         struct  prison *pt_prison;
 115 };
 116
 117 #define PF_PKT          0x08            /* packet mode */
 118 #define PF_STOPPED      0x10            /* user told stopped */
 119 #define PF_REMOTE       0x20            /* remote and flow controlled input */
 120 #define PF_NOSTOP       0x40
 121 #define PF_UCNTL        0x80            /* user control mode */
 122
 123 /*
 124  * This function creates and initializes a pts/ptc pair
 125  *
 126  * pts == /dev/tty[pqrsPQRS][0123456789abcdefghijklmnopqrstuv]
 127  * ptc == /dev/pty[pqrsPQRS][0123456789abcdefghijklmnopqrstuv]
 128  *
 129  * XXX: define and add mapping of upper minor bits to allow more
 130  *      than 256 ptys.
 131  */
 132 static void
 133 ptyinit(int n)
 134 {
 135         cdev_t devs, devc;
 136         char *names = "pqrsPQRS";
 137         struct pt_ioctl *pt;
 138
 139         /* For now we only map the lower 8 bits of the minor */
 140         if (n & ~0xff)
 141                 return;
 142
 143         pt = kmalloc(sizeof(*pt), M_PTY, M_WAITOK | M_ZERO);
 144         pt->devs = devs = make_dev(&pts_ops, n,
 145             0, 0, 0666, "tty%c%r", names[n / 32], n % 32);
 146         pt->devc = devc = make_dev(&ptc_ops, n,
 147             0, 0, 0666, "pty%c%r", names[n / 32], n % 32);
 148
 149         devs->si_drv1 = devc->si_drv1 = pt;
 150         devs->si_tty = devc->si_tty = &pt->pt_tty;
 151         pt->pt_tty.t_dev = devs;
 152         ttyregister(&pt->pt_tty);
 153 }
 154
 155 /*ARGSUSED*/
 156 static  int
 157 ptsopen(struct dev_open_args *ap)
 158 {
 159         cdev_t dev = ap->a_head.a_dev;
 160         struct tty *tp;
 161         int error;
 162 #if 0
 163         int minr;
 164         cdev_t nextdev;
 165 #endif
 166         struct pt_ioctl *pti;
 167
 168 #if 0
 169         minr = lminor(dev);
 170         /*
 171          * REMOVED gross hack for devfs.  also note that makedev()
 172          * no longer exists in this form and reference counting makes
 173          * this a problem if we don't clean it out later.
 174          */
 175         if (minr < 255) {
 176                 nextdev = make_sub_dev(dev, minr + 1);
 177                 if (!nextdev->si_drv1) {
 178                         ptyinit(minr + 1);
 179                 }
 180         }
 181 #endif
 182         if (!dev->si_drv1)
 183                 ptyinit(minor(dev));
 184         if (!dev->si_drv1)
 185                 return(ENXIO);
 186         pti = dev->si_drv1;
 187         tp = dev->si_tty;
 188         if ((tp->t_state & TS_ISOPEN) == 0) {
 189                 ttychars(tp);           /* Set up default chars */
 190                 tp->t_iflag = TTYDEF_IFLAG;
 191                 tp->t_oflag = TTYDEF_OFLAG;
 192                 tp->t_lflag = TTYDEF_LFLAG;
 193                 tp->t_cflag = TTYDEF_CFLAG;
 194                 tp->t_ispeed = tp->t_ospeed = TTYDEF_SPEED;
 195         } else if ((tp->t_state & TS_XCLUDE) && priv_check_cred(ap->a_cred, PRIV_ROOT, 0)) {
 196                 return (EBUSY);
 197         } else if (pti->pt_prison != ap->a_cred->cr_prison) {
 198                 return (EBUSY);
 199         }
 200         if (tp->t_oproc)                        /* Ctrlr still around. */
 201                 (void)(*linesw[tp->t_line].l_modem)(tp, 1);
 202         while ((tp->t_state & TS_CARR_ON) == 0) {
 203                 if (ap->a_oflags & FNONBLOCK)
 204                         break;
 205                 error = ttysleep(tp, TSA_CARR_ON(tp), PCATCH, "ptsopn", 0);
 206                 if (error)
 207                         return (error);
 208         }
 209         error = (*linesw[tp->t_line].l_open)(dev, tp);
 210         if (error == 0)
 211                 ptcwakeup(tp, FREAD|FWRITE);
 212         return (error);
 213 }
 214
 215 static  int
 216 ptsclose(struct dev_close_args *ap)
 217 {
 218         cdev_t dev = ap->a_head.a_dev;
 219         struct tty *tp;
 220         int err;
 221
 222         tp = dev->si_tty;
 223         err = (*linesw[tp->t_line].l_close)(tp, ap->a_fflag);
 224         ptsstop(tp, FREAD|FWRITE);
 225         (void) ttyclose(tp);
 226         return (err);
 227 }
 228
 229 static  int
 230 ptsread(struct dev_read_args *ap)
 231 {
 232         cdev_t dev = ap->a_head.a_dev;
 233         struct proc *p = curproc;
 234         struct tty *tp = dev->si_tty;
 235         struct pt_ioctl *pti = dev->si_drv1;
 236         struct lwp *lp;
 237
 238         int error = 0;
 239
 240         lp = curthread->td_lwp;
 241
 242 again:
 243         if (pti->pt_flags & PF_REMOTE) {
 244                 while (isbackground(p, tp)) {
 245                         if (SIGISMEMBER(p->p_sigignore, SIGTTIN) ||
 246                             SIGISMEMBER(lp->lwp_sigmask, SIGTTIN) ||
 247                             p->p_pgrp->pg_jobc == 0 || p->p_flag & P_PPWAIT)
 248                                 return (EIO);
 249                         pgsignal(p->p_pgrp, SIGTTIN, 1);
 250                         error = ttysleep(tp, &lbolt, PCATCH, "ptsbg", 0);
 251                         if (error)
 252                                 return (error);
 253                 }
 254                 if (tp->t_canq.c_cc == 0) {
 255                         if (ap->a_ioflag & IO_NDELAY)
 256                                 return (EWOULDBLOCK);
 257                         error = ttysleep(tp, TSA_PTS_READ(tp), PCATCH,
 258                                          "ptsin", 0);
 259                         if (error)
 260                                 return (error);
 261                         goto again;
 262                 }
 263                 while (tp->t_canq.c_cc > 1 && ap->a_uio->uio_resid > 0)
 264                         if (ureadc(clist_getc(&tp->t_canq), ap->a_uio) < 0) {
 265                                 error = EFAULT;
 266                                 break;
 267                         }
 268                 if (tp->t_canq.c_cc == 1)
 269                         clist_getc(&tp->t_canq);
 270                 if (tp->t_canq.c_cc)
 271                         return (error);
 272         } else
 273                 if (tp->t_oproc)
 274                         error = (*linesw[tp->t_line].l_read)(tp, ap->a_uio, ap->a_ioflag);
 275         ptcwakeup(tp, FWRITE);
 276         return (error);
 277 }
 278
 279 /*
 280  * Write to pseudo-tty.
 281  * Wakeups of controlling tty will happen
 282  * indirectly, when tty driver calls ptsstart.
 283  */
 284 static  int
 285 ptswrite(struct dev_write_args *ap)
 286 {
 287         cdev_t dev = ap->a_head.a_dev;
 288         struct tty *tp;
 289
 290         tp = dev->si_tty;
 291         if (tp->t_oproc == 0)
 292                 return (EIO);
 293         return ((*linesw[tp->t_line].l_write)(tp, ap->a_uio, ap->a_ioflag));
 294 }
 295
 296 /*
 297  * Start output on pseudo-tty.
 298  * Wake up process selecting or sleeping for input from controlling tty.
 299  */
 300 static void
 301 ptsstart(struct tty *tp)
 302 {
 303         struct pt_ioctl *pti = tp->t_dev->si_drv1;
 304
 305         if (tp->t_state & TS_TTSTOP)
 306                 return;
 307         if (pti->pt_flags & PF_STOPPED) {
 308                 pti->pt_flags &= ~PF_STOPPED;
 309                 pti->pt_send = TIOCPKT_START;
 310         }
 311         ptcwakeup(tp, FREAD);
 312 }
 313
 314 static void
 315 ptcwakeup(struct tty *tp, int flag)
 316 {
 317         struct pt_ioctl *pti = tp->t_dev->si_drv1;
 318
 319         if (flag & FREAD) {
 320                 selwakeup(&pti->pt_selr);
 321                 wakeup(TSA_PTC_READ(tp));
 322         }
 323         if (flag & FWRITE) {
 324                 selwakeup(&pti->pt_selw);
 325                 wakeup(TSA_PTC_WRITE(tp));
 326         }
 327 }
 328
 329 static  int
 330 ptcopen(struct dev_open_args *ap)
 331 {
 332         cdev_t dev = ap->a_head.a_dev;
 333         struct tty *tp;
 334         struct pt_ioctl *pti;
 335
 336         if (!dev->si_drv1)
 337                 ptyinit(minor(dev));
 338         if (!dev->si_drv1)
 339                 return(ENXIO);
 340         tp = dev->si_tty;
 341         if (tp->t_oproc)
 342                 return (EIO);
 343         tp->t_oproc = ptsstart;
 344         tp->t_stop = ptsstop;
 345         (void)(*linesw[tp->t_line].l_modem)(tp, 1);
 346         tp->t_lflag &= ~EXTPROC;
 347         pti = dev->si_drv1;
 348         pti->pt_prison = ap->a_cred->cr_prison;
 349         pti->pt_flags = 0;
 350         pti->pt_send = 0;
 351         pti->pt_ucntl = 0;
 352         return (0);
 353 }
 354
 355 static  int
 356 ptcclose(struct dev_close_args *ap)
 357 {
 358         cdev_t dev = ap->a_head.a_dev;
 359         struct tty *tp;
 360
 361         tp = dev->si_tty;
 362         (void)(*linesw[tp->t_line].l_modem)(tp, 0);
 363
 364         /*
 365          * XXX MDMBUF makes no sense for ptys but would inhibit the above
 366          * l_modem().  CLOCAL makes sense but isn't supported.   Special
 367          * l_modem()s that ignore carrier drop make no sense for ptys but
 368          * may be in use because other parts of the line discipline make
 369          * sense for ptys.  Recover by doing everything that a normal
 370          * ttymodem() would have done except for sending a SIGHUP.
 371          */
 372         if (tp->t_state & TS_ISOPEN) {
 373                 tp->t_state &= ~(TS_CARR_ON | TS_CONNECTED);
 374                 tp->t_state |= TS_ZOMBIE;
 375                 ttyflush(tp, FREAD | FWRITE);
 376         }
 377
 378         tp->t_oproc = 0;                /* mark closed */
 379         return (0);
 380 }
 381
 382 static  int
 383 ptcread(struct dev_read_args *ap)
 384 {
 385         cdev_t dev = ap->a_head.a_dev;
 386         struct tty *tp = dev->si_tty;
 387         struct pt_ioctl *pti = dev->si_drv1;
 388         char buf[BUFSIZ];
 389         int error = 0, cc;
 390
 391         /*
 392          * We want to block until the slave
 393          * is open, and there's something to read;
 394          * but if we lost the slave or we're NBIO,
 395          * then return the appropriate error instead.
 396          */
 397         for (;;) {
 398                 if (tp->t_state&TS_ISOPEN) {
 399                         if (pti->pt_flags&PF_PKT && pti->pt_send) {
 400                                 error = ureadc((int)pti->pt_send, ap->a_uio);
 401                                 if (error)
 402                                         return (error);
 403                                 if (pti->pt_send & TIOCPKT_IOCTL) {
 404                                         cc = min(ap->a_uio->uio_resid,
 405                                                 sizeof(tp->t_termios));
 406                                         uiomove((caddr_t)&tp->t_termios, cc,
 407                                                 ap->a_uio);
 408                                 }
 409                                 pti->pt_send = 0;
 410                                 return (0);
 411                         }
 412                         if (pti->pt_flags&PF_UCNTL && pti->pt_ucntl) {
 413                                 error = ureadc((int)pti->pt_ucntl, ap->a_uio);
 414                                 if (error)
 415                                         return (error);
 416                                 pti->pt_ucntl = 0;
 417                                 return (0);
 418                         }
 419                         if (tp->t_outq.c_cc && (tp->t_state&TS_TTSTOP) == 0)
 420                                 break;
 421                 }
 422                 if ((tp->t_state & TS_CONNECTED) == 0)
 423                         return (0);     /* EOF */
 424                 if (ap->a_ioflag & IO_NDELAY)
 425                         return (EWOULDBLOCK);
 426                 error = tsleep(TSA_PTC_READ(tp), PCATCH, "ptcin", 0);
 427                 if (error)
 428                         return (error);
 429         }
 430         if (pti->pt_flags & (PF_PKT|PF_UCNTL))
 431                 error = ureadc(0, ap->a_uio);
 432         while (ap->a_uio->uio_resid > 0 && error == 0) {
 433                 cc = q_to_b(&tp->t_outq, buf, min(ap->a_uio->uio_resid, BUFSIZ));
 434                 if (cc <= 0)
 435                         break;
 436                 error = uiomove(buf, cc, ap->a_uio);
 437         }
 438         ttwwakeup(tp);
 439         return (error);
 440 }
 441
 442 static  void
 443 ptsstop(struct tty *tp, int flush)
 444 {
 445         struct pt_ioctl *pti = tp->t_dev->si_drv1;
 446         int flag;
 447
 448         /* note: FLUSHREAD and FLUSHWRITE already ok */
 449         if (flush == 0) {
 450                 flush = TIOCPKT_STOP;
 451                 pti->pt_flags |= PF_STOPPED;
 452         } else
 453                 pti->pt_flags &= ~PF_STOPPED;
 454         pti->pt_send |= flush;
 455         /* change of perspective */
 456         flag = 0;
 457         if (flush & FREAD)
 458                 flag |= FWRITE;
 459         if (flush & FWRITE)
 460                 flag |= FREAD;
 461         ptcwakeup(tp, flag);
 462 }
 463
 464 static  int
 465 ptcpoll(struct dev_poll_args *ap)
 466 {
 467         cdev_t dev = ap->a_head.a_dev;
 468         struct tty *tp = dev->si_tty;
 469         struct pt_ioctl *pti = dev->si_drv1;
 470         int revents = 0;
 471
 472         if ((tp->t_state & TS_CONNECTED) == 0) {
 473                 ap->a_events = seltrue(dev, ap->a_events) | POLLHUP;
 474                 return(0);
 475         }
 476
 477         /*
 478          * Need to block timeouts (ttrstart).
 479          */
 480         crit_enter();
 481
 482         if (ap->a_events & (POLLIN | POLLRDNORM))
 483                 if ((tp->t_state & TS_ISOPEN) &&
 484                     ((tp->t_outq.c_cc && (tp->t_state & TS_TTSTOP) == 0) ||
 485                      ((pti->pt_flags & PF_PKT) && pti->pt_send) ||
 486                      ((pti->pt_flags & PF_UCNTL) && pti->pt_ucntl)))
 487                         revents |= ap->a_events & (POLLIN | POLLRDNORM);
 488
 489         if (ap->a_events & (POLLOUT | POLLWRNORM))
 490                 if (tp->t_state & TS_ISOPEN &&
 491                     ((pti->pt_flags & PF_REMOTE) ?
 492                      (tp->t_canq.c_cc == 0) :
 493                      ((tp->t_rawq.c_cc + tp->t_canq.c_cc < TTYHOG - 2) ||
 494                       (tp->t_canq.c_cc == 0 && (tp->t_lflag & ICANON)))))
 495                         revents |= ap->a_events & (POLLOUT | POLLWRNORM);
 496
 497         if (ap->a_events & POLLHUP)
 498                 if ((tp->t_state & TS_CARR_ON) == 0)
 499                         revents |= POLLHUP;
 500
 501         if (revents == 0) {
 502                 if (ap->a_events & (POLLIN | POLLRDNORM))
 503                         selrecord(curthread, &pti->pt_selr);
 504
 505                 if (ap->a_events & (POLLOUT | POLLWRNORM))
 506                         selrecord(curthread, &pti->pt_selw);
 507         }
 508         crit_exit();
 509
 510         ap->a_events = revents;
 511         return (0);
 512 }
 513
 514 static  int
 515 ptcwrite(struct dev_write_args *ap)
 516 {
 517         cdev_t dev = ap->a_head.a_dev;
 518         struct tty *tp = dev->si_tty;
 519         u_char *cp = 0;
 520         int cc = 0;
 521         u_char locbuf[BUFSIZ];
 522         int cnt = 0;
 523         struct pt_ioctl *pti = dev->si_drv1;
 524         int error = 0;
 525
 526 again:
 527         if ((tp->t_state&TS_ISOPEN) == 0)
 528                 goto block;
 529         if (pti->pt_flags & PF_REMOTE) {
 530                 if (tp->t_canq.c_cc)
 531                         goto block;
 532                 while ((ap->a_uio->uio_resid > 0 || cc > 0) &&
 533                        tp->t_canq.c_cc < TTYHOG - 1) {
 534                         if (cc == 0) {
 535                                 cc = min(ap->a_uio->uio_resid, BUFSIZ);
 536                                 cc = min(cc, TTYHOG - 1 - tp->t_canq.c_cc);
 537                                 cp = locbuf;
 538                                 error = uiomove((caddr_t)cp, cc, ap->a_uio);
 539                                 if (error)
 540                                         return (error);
 541                                 /* check again for safety */
 542                                 if ((tp->t_state & TS_ISOPEN) == 0) {
 543                                         /* adjust as usual */
 544                                         ap->a_uio->uio_resid += cc;
 545                                         return (EIO);
 546                                 }
 547                         }
 548                         if (cc > 0) {
 549                                 cc = b_to_q((char *)cp, cc, &tp->t_canq);
 550                                 /*
 551                                  * XXX we don't guarantee that the canq size
 552                                  * is >= TTYHOG, so the above b_to_q() may
 553                                  * leave some bytes uncopied.  However, space
 554                                  * is guaranteed for the null terminator if
 555                                  * we don't fail here since (TTYHOG - 1) is
 556                                  * not a multiple of CBSIZE.
 557                                  */
 558                                 if (cc > 0)
 559                                         break;
 560                         }
 561                 }
 562                 /* adjust for data copied in but not written */
 563                 ap->a_uio->uio_resid += cc;
 564                 clist_putc(0, &tp->t_canq);
 565                 ttwakeup(tp);
 566                 wakeup(TSA_PTS_READ(tp));
 567                 return (0);
 568         }
 569         while (ap->a_uio->uio_resid > 0 || cc > 0) {
 570                 if (cc == 0) {
 571                         cc = min(ap->a_uio->uio_resid, BUFSIZ);
 572                         cp = locbuf;
 573                         error = uiomove((caddr_t)cp, cc, ap->a_uio);
 574                         if (error)
 575                                 return (error);
 576                         /* check again for safety */
 577                         if ((tp->t_state & TS_ISOPEN) == 0) {
 578                                 /* adjust for data copied in but not written */
 579                                 ap->a_uio->uio_resid += cc;
 580                                 return (EIO);
 581                         }
 582                 }
 583                 while (cc > 0) {
 584                         if ((tp->t_rawq.c_cc + tp->t_canq.c_cc) >= TTYHOG - 2 &&
 585                            (tp->t_canq.c_cc > 0 || !(tp->t_lflag&ICANON))) {
 586                                 wakeup(TSA_HUP_OR_INPUT(tp));
 587                                 goto block;
 588                         }
 589                         (*linesw[tp->t_line].l_rint)(*cp++, tp);
 590                         cnt++;
 591                         cc--;
 592                 }
 593                 cc = 0;
 594         }
 595         return (0);
 596 block:
 597         /*
 598          * Come here to wait for slave to open, for space
 599          * in outq, or space in rawq, or an empty canq.
 600          */
 601         if ((tp->t_state & TS_CONNECTED) == 0) {
 602                 /* adjust for data copied in but not written */
 603                 ap->a_uio->uio_resid += cc;
 604                 return (EIO);
 605         }
 606         if (ap->a_ioflag & IO_NDELAY) {
 607                 /* adjust for data copied in but not written */
 608                 ap->a_uio->uio_resid += cc;
 609                 if (cnt == 0)
 610                         return (EWOULDBLOCK);
 611                 return (0);
 612         }
 613         error = tsleep(TSA_PTC_WRITE(tp), PCATCH, "ptcout", 0);
 614         if (error) {
 615                 /* adjust for data copied in but not written */
 616                 ap->a_uio->uio_resid += cc;
 617                 return (error);
 618         }
 619         goto again;
 620 }
 621
 622 /*ARGSUSED*/
 623 static  int
 624 ptyioctl(struct dev_ioctl_args *ap)
 625 {
 626         cdev_t dev = ap->a_head.a_dev;
 627         struct tty *tp = dev->si_tty;
 628         struct pt_ioctl *pti = dev->si_drv1;
 629         u_char *cc = tp->t_cc;
 630         int stop, error;
 631
 632         if (dev_dflags(dev) & D_MASTER) {
 633                 switch (ap->a_cmd) {
 634
 635                 case TIOCGPGRP:
 636                         /*
 637                          * We avoid calling ttioctl on the controller since,
 638                          * in that case, tp must be the controlling terminal.
 639                          */
 640                         *(int *)ap->a_data = tp->t_pgrp ? tp->t_pgrp->pg_id : 0;
 641                         return (0);
 642
 643                 case TIOCPKT:
 644                         if (*(int *)ap->a_data) {
 645                                 if (pti->pt_flags & PF_UCNTL)
 646                                         return (EINVAL);
 647                                 pti->pt_flags |= PF_PKT;
 648                         } else
 649                                 pti->pt_flags &= ~PF_PKT;
 650                         return (0);
 651
 652                 case TIOCUCNTL:
 653                         if (*(int *)ap->a_data) {
 654                                 if (pti->pt_flags & PF_PKT)
 655                                         return (EINVAL);
 656                                 pti->pt_flags |= PF_UCNTL;
 657                         } else
 658                                 pti->pt_flags &= ~PF_UCNTL;
 659                         return (0);
 660
 661                 case TIOCREMOTE:
 662                         if (*(int *)ap->a_data)
 663                                 pti->pt_flags |= PF_REMOTE;
 664                         else
 665                                 pti->pt_flags &= ~PF_REMOTE;
 666                         ttyflush(tp, FREAD|FWRITE);
 667                         return (0);
 668                 }
 669
 670                 /*
 671                  * The rest of the ioctls shouldn't be called until
 672                  * the slave is open.
 673                  */
 674                 if ((tp->t_state & TS_ISOPEN) == 0)
 675                         return (EAGAIN);
 676
 677                 switch (ap->a_cmd) {
 678 #ifdef COMPAT_43
 679                 case TIOCSETP:
 680                 case TIOCSETN:
 681 #endif
 682                 case TIOCSETD:
 683                 case TIOCSETA:
 684                 case TIOCSETAW:
 685                 case TIOCSETAF:
 686                         /*
 687                          * IF CONTROLLER STTY THEN MUST FLUSH TO PREVENT A HANG.
 688                          * ttywflush(tp) will hang if there are characters in
 689                          * the outq.
 690                          */
 691                         ndflush(&tp->t_outq, tp->t_outq.c_cc);
 692                         break;
 693
 694                 case TIOCSIG:
 695                         if (*(unsigned int *)ap->a_data >= NSIG ||
 696                             *(unsigned int *)ap->a_data == 0)
 697                                 return(EINVAL);
 698                         if ((tp->t_lflag&NOFLSH) == 0)
 699                                 ttyflush(tp, FREAD|FWRITE);
 700                         pgsignal(tp->t_pgrp, *(unsigned int *)ap->a_data, 1);
 701                         if ((*(unsigned int *)ap->a_data == SIGINFO) &&
 702                             ((tp->t_lflag&NOKERNINFO) == 0))
 703                                 ttyinfo(tp);
 704                         return(0);
 705                 }
 706         }
 707         if (ap->a_cmd == TIOCEXT) {
 708                 /*
 709                  * When the EXTPROC bit is being toggled, we need
 710                  * to send an TIOCPKT_IOCTL if the packet driver
 711                  * is turned on.
 712                  */
 713                 if (*(int *)ap->a_data) {
 714                         if (pti->pt_flags & PF_PKT) {
 715                                 pti->pt_send |= TIOCPKT_IOCTL;
 716                                 ptcwakeup(tp, FREAD);
 717                         }
 718                         tp->t_lflag |= EXTPROC;
 719                 } else {
 720                         if ((tp->t_lflag & EXTPROC) &&
 721                             (pti->pt_flags & PF_PKT)) {
 722                                 pti->pt_send |= TIOCPKT_IOCTL;
 723                                 ptcwakeup(tp, FREAD);
 724                         }
 725                         tp->t_lflag &= ~EXTPROC;
 726                 }
 727                 return(0);
 728         }
 729         error = (*linesw[tp->t_line].l_ioctl)(tp, ap->a_cmd, ap->a_data,
 730                                               ap->a_fflag, ap->a_cred);
 731         if (error == ENOIOCTL)
 732                  error = ttioctl(tp, ap->a_cmd, ap->a_data, ap->a_fflag);
 733         if (error == ENOIOCTL) {
 734                 if (pti->pt_flags & PF_UCNTL &&
 735                     (ap->a_cmd & ~0xff) == UIOCCMD(0)) {
 736                         if (ap->a_cmd & 0xff) {
 737                                 pti->pt_ucntl = (u_char)ap->a_cmd;
 738                                 ptcwakeup(tp, FREAD);
 739                         }
 740                         return (0);
 741                 }
 742                 error = ENOTTY;
 743         }
 744         /*
 745          * If external processing and packet mode send ioctl packet.
 746          */
 747         if ((tp->t_lflag&EXTPROC) && (pti->pt_flags & PF_PKT)) {
 748                 switch(ap->a_cmd) {
 749                 case TIOCSETA:
 750                 case TIOCSETAW:
 751                 case TIOCSETAF:
 752 #ifdef COMPAT_43
 753                 case TIOCSETP:
 754                 case TIOCSETN:
 755 #endif
 756 #if defined(COMPAT_43) || defined(COMPAT_SUNOS)
 757                 case TIOCSETC:
 758                 case TIOCSLTC:
 759                 case TIOCLBIS:
 760                 case TIOCLBIC:
 761                 case TIOCLSET:
 762 #endif
 763                         pti->pt_send |= TIOCPKT_IOCTL;
 764                         ptcwakeup(tp, FREAD);
 765                 default:
 766                         break;
 767                 }
 768         }
 769         stop = (tp->t_iflag & IXON) && CCEQ(cc[VSTOP], CTRL('s'))
 770                 && CCEQ(cc[VSTART], CTRL('q'));
 771         if (pti->pt_flags & PF_NOSTOP) {
 772                 if (stop) {
 773                         pti->pt_send &= ~TIOCPKT_NOSTOP;
 774                         pti->pt_send |= TIOCPKT_DOSTOP;
 775                         pti->pt_flags &= ~PF_NOSTOP;
 776                         ptcwakeup(tp, FREAD);
 777                 }
 778         } else {
 779                 if (!stop) {
 780                         pti->pt_send &= ~TIOCPKT_DOSTOP;
 781                         pti->pt_send |= TIOCPKT_NOSTOP;
 782                         pti->pt_flags |= PF_NOSTOP;
 783                         ptcwakeup(tp, FREAD);
 784                 }
 785         }
 786         return (error);
 787 }
 788
 789
 790 static void ptc_drvinit (void *unused);
 791
 792 static void
 793 ptc_drvinit(void *unused)
 794 {
 795         dev_ops_add(&pts_ops, 0, 0);
 796         dev_ops_add(&ptc_ops, 0, 0);
 797         /* XXX: Gross hack for DEVFS */
 798         /* XXX: DEVFS is no more, should this be removed? */
 799         ptyinit(0);
 800 }
 801
 802 SYSINIT(ptcdev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR_C,ptc_drvinit,NULL)