bsd/kern/tty_pty.c

   1 /*
   2  * Copyright (c) 1997-2006 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28 /*
  29  * Copyright (c) 1982, 1986, 1989, 1993
  30  *      The Regents of the University of California.  All rights reserved.
  31  *
  32  * Redistribution and use in source and binary forms, with or without
  33  * modification, are permitted provided that the following conditions
  34  * are met:
  35  * 1. Redistributions of source code must retain the above copyright
  36  *    notice, this list of conditions and the following disclaimer.
  37  * 2. Redistributions in binary form must reproduce the above copyright
  38  *    notice, this list of conditions and the following disclaimer in the
  39  *    documentation and/or other materials provided with the distribution.
  40  * 3. All advertising materials mentioning features or use of this software
  41  *    must display the following acknowledgement:
  42  *      This product includes software developed by the University of
  43  *      California, Berkeley and its contributors.
  44  * 4. Neither the name of the University nor the names of its contributors
  45  *    may be used to endorse or promote products derived from this software
  46  *    without specific prior written permission.
  47  *
  48  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  49  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  50  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  51  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  52  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  53  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  54  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  55  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  56  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  57  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  58  * SUCH DAMAGE.
  59  *
  60  *      @(#)tty_pty.c   8.4 (Berkeley) 2/20/95
  61  */
  62
  63 /*
  64  * Pseudo-teletype Driver
  65  * (Actually two drivers, requiring two entries in 'cdevsw')
  66  */
  67 #include "pty.h"                /* XXX */
  68
  69 #include <sys/param.h>
  70 #include <sys/systm.h>
  71 #include <sys/ioctl.h>
  72 #include <sys/proc_internal.h>
  73 #include <sys/kauth.h>
  74 #include <sys/tty.h>
  75 #include <sys/conf.h>
  76 #include <sys/file_internal.h>
  77 #include <sys/uio.h>
  78 #include <sys/kernel.h>
  79 #include <sys/vnode.h>
  80 #include <sys/user.h>
  81 #include <sys/signalvar.h>
  82
  83 #define d_devtotty_t    struct tty **
  84
  85 #ifdef d_stop_t
  86 #undef d_stop_t
  87 #endif
  88 typedef void d_stop_t(struct tty *tp, int rw);
  89
  90 /* XXX function should be removed??? */
  91 int pty_init(int n_ptys);
  92
  93 /* XXX should be a devfs function */
  94 int _devfs_setattr(void * handle, unsigned short mode, uid_t uid, gid_t gid);
  95
  96 static void ptsstart(struct tty *tp);
  97 static void ptcwakeup(struct tty *tp, int flag);
  98
  99 __private_extern__      d_open_t        ptsopen;
 100 __private_extern__      d_close_t       ptsclose;
 101 __private_extern__      d_read_t        ptsread;
 102 __private_extern__      d_write_t       ptswrite;
 103 __private_extern__      d_ioctl_t       ptyioctl;
 104 __private_extern__      d_stop_t        ptsstop;
 105 __private_extern__      d_devtotty_t    ptydevtotty;
 106 __private_extern__      d_open_t        ptcopen;
 107 __private_extern__      d_close_t       ptcclose;
 108 __private_extern__      d_read_t        ptcread;
 109 __private_extern__      d_write_t       ptcwrite;
 110 __private_extern__      d_select_t      ptcselect;
 111
 112 #if NPTY == 1
 113 #undef NPTY
 114 #define NPTY    32              /* crude XXX */
 115 #warning        You have only one pty defined, redefining to 32.
 116 #endif
 117
 118 #define BUFSIZ 100              /* Chunk size iomoved to/from user */
 119
 120 /*
 121  * pts == /dev/tty[pqrsPQRS][0123456789abcdefghijklmnopqrstuv]
 122  * ptc == /dev/pty[pqrsPQRS][0123456789abcdefghijklmnopqrstuv]
 123  */
 124 /* All references to have been changed to indirections in the file */
 125 __private_extern__ struct       tty *pt_tty[NPTY] = { NULL };
 126
 127 static struct   pt_ioctl {
 128         int     pt_flags;
 129         struct  selinfo pt_selr, pt_selw;
 130         u_char  pt_send;
 131         u_char  pt_ucntl;
 132         void    *pt_devhandle;  /* slave device handle for grantpt() */
 133 } pt_ioctl[NPTY];               /* XXX */
 134 static int      npty = NPTY;            /* for pstat -t */
 135
 136 #define PF_PKT          0x08            /* packet mode */
 137 #define PF_STOPPED      0x10            /* user told stopped */
 138 #define PF_REMOTE       0x20            /* remote and flow controlled input */
 139 #define PF_NOSTOP       0x40
 140 #define PF_UCNTL        0x80            /* user control mode */
 141
 142 #ifndef DEVFS
 143 int
 144 pty_init(__unused int n_ptys)
 145 {
 146     return 0;
 147 }
 148 #else
 149 #include <miscfs/devfs/devfs.h>
 150 #define START_CHAR      'p'
 151 #define HEX_BASE        16
 152 int
 153 pty_init(int n_ptys)
 154 {
 155     int         i;
 156     int         j;
 157
 158     /* create the pseudo tty device nodes */
 159     for (j = 0; j < 10; j++) {
 160         for (i = 0; i < HEX_BASE; i++) {
 161             int m = j * HEX_BASE + i;
 162             if (m == n_ptys)
 163                 goto done;
 164             pt_ioctl[m].pt_devhandle = devfs_make_node(makedev(4, m),
 165                                   DEVFS_CHAR, UID_ROOT, GID_WHEEL, 0666,
 166                                   "tty%c%x", j + START_CHAR, i);
 167             (void)devfs_make_node(makedev(5, m),
 168                                   DEVFS_CHAR, UID_ROOT, GID_WHEEL, 0666,
 169                                   "pty%c%x", j + START_CHAR, i);
 170         }
 171     }
 172  done:
 173     return (0);
 174 }
 175 #endif /* DEVFS */
 176
 177 __private_extern__ int
 178 ptsopen(dev_t dev, int flag, __unused int devtype, __unused struct proc *p)
 179 {
 180         struct tty *tp;
 181         int error;
 182         boolean_t   funnel_state;
 183
 184         funnel_state = thread_funnel_set(kernel_flock, TRUE);
 185         /*
 186          * You will see this sort of code coming up in diffs later both
 187          * the ttymalloc and the tp indirection.
 188          */
 189         if (minor(dev) >= npty) {
 190                 error = ENXIO;
 191                 goto out;
 192         }
 193         if (!pt_tty[minor(dev)]) {
 194                 /*
 195                  * If we can't allocate a new one, act as if we had run out
 196                  * of device nodes.
 197                  */
 198                 if ((tp = pt_tty[minor(dev)] = ttymalloc()) == NULL) {
 199                         error = ENXIO;
 200                         goto out;
 201                 }
 202         } else
 203                 tp = pt_tty[minor(dev)];
 204         if ((tp->t_state & TS_ISOPEN) == 0) {
 205                 ttychars(tp);           /* Set up default chars */
 206                 tp->t_iflag = TTYDEF_IFLAG;
 207                 tp->t_oflag = TTYDEF_OFLAG;
 208                 tp->t_lflag = TTYDEF_LFLAG;
 209                 tp->t_cflag = TTYDEF_CFLAG;
 210                 tp->t_ispeed = tp->t_ospeed = TTYDEF_SPEED;
 211                 ttsetwater(tp);         /* would be done in xxparam() */
 212         } else if (tp->t_state&TS_XCLUDE && suser(kauth_cred_get(), NULL)) {
 213                 error = EBUSY;
 214                 goto out;
 215         }
 216         if (tp->t_oproc)                        /* Ctrlr still around. */
 217                 (void)(*linesw[tp->t_line].l_modem)(tp, 1);
 218         while ((tp->t_state & TS_CARR_ON) == 0) {
 219                 if (flag&FNONBLOCK)
 220                         break;
 221                 error = ttysleep(tp, TSA_CARR_ON(tp), TTIPRI | PCATCH,
 222                                  "ptsopn", 0);
 223                 if (error)
 224                         goto out;
 225         }
 226         error = (*linesw[tp->t_line].l_open)(dev, tp);
 227         if (error == 0)
 228                 ptcwakeup(tp, FREAD|FWRITE);
 229 out:
 230         (void) thread_funnel_set(kernel_flock, funnel_state);
 231         return (error);
 232 }
 233
 234 __private_extern__ int
 235 ptsclose(dev_t dev, int flag, __unused int mode, __unused proc_t p)
 236 {
 237         struct tty *tp;
 238         int err;
 239         boolean_t   funnel_state;
 240         /*
 241          * This is temporary until the VSX conformance tests
 242          * are fixed.  They are hanging with a deadlock
 243          * where close(pts) will not complete without t_timeout set
 244          */
 245 #define FIX_VSX_HANG    1
 246 #ifdef  FIX_VSX_HANG
 247         int save_timeout;
 248 #endif
 249         funnel_state = thread_funnel_set(kernel_flock, TRUE);
 250
 251         tp = pt_tty[minor(dev)];
 252 #ifdef  FIX_VSX_HANG
 253         save_timeout = tp->t_timeout;
 254         tp->t_timeout = 60;
 255 #endif
 256         err = (*linesw[tp->t_line].l_close)(tp, flag);
 257         ptsstop(tp, FREAD|FWRITE);
 258         (void) ttyclose(tp);
 259 #ifdef  FIX_VSX_HANG
 260         tp->t_timeout = save_timeout;
 261 #endif
 262         (void) thread_funnel_set(kernel_flock, funnel_state);
 263         return (err);
 264 }
 265
 266 __private_extern__ int
 267 ptsread(dev_t dev, struct uio *uio, int flag)
 268 {
 269         struct proc *p = current_proc();
 270         struct tty *tp = pt_tty[minor(dev)];
 271         struct pt_ioctl *pti = &pt_ioctl[minor(dev)];
 272         int error = 0;
 273         struct uthread *ut;
 274         boolean_t   funnel_state;
 275         struct pgrp *pg;
 276
 277         funnel_state = thread_funnel_set(kernel_flock, TRUE);
 278
 279
 280         ut = (struct uthread *)get_bsdthread_info(current_thread());
 281 again:
 282         if (pti->pt_flags & PF_REMOTE) {
 283                 while (isbackground(p, tp)) {
 284                         if ((p->p_sigignore & sigmask(SIGTTIN)) ||
 285                             (ut->uu_sigmask & sigmask(SIGTTIN)) ||
 286                             p->p_lflag & P_LPPWAIT) {
 287                                 error = EIO;
 288                                 goto out;
 289                         }
 290
 291
 292                         pg = proc_pgrp(p);
 293                         if (pg == PGRP_NULL) {
 294                                 error = EIO;
 295                                 goto out;
 296                         }
 297                         if (pg->pg_jobc == 0) {
 298                                 pg_rele(pg);
 299                                 error = EIO;
 300                                 goto out;
 301                         }
 302                         pgsignal(pg, SIGTTIN, 1);
 303                         pg_rele(pg);
 304
 305                         error = ttysleep(tp, &lbolt, TTIPRI | PCATCH | PTTYBLOCK, "ptsbg",
 306                                          0);
 307                         if (error)
 308                                 goto out;
 309                 }
 310                 if (tp->t_canq.c_cc == 0) {
 311                         if (flag & IO_NDELAY)
 312                                 return (EWOULDBLOCK);
 313                         error = ttysleep(tp, TSA_PTS_READ(tp), TTIPRI | PCATCH,
 314                                          "ptsin", 0);
 315                         if (error)
 316                                 goto out;
 317                         goto again;
 318                 }
 319                 while (tp->t_canq.c_cc > 1 && uio_resid(uio) > 0) {
 320                         int cc;
 321                         char buf[BUFSIZ];
 322
 323                         cc = min(uio_resid(uio), BUFSIZ);
 324                         // Don't copy the very last byte
 325                         cc = min(cc, tp->t_canq.c_cc - 1);
 326                         cc = q_to_b(&tp->t_canq, (u_char *)buf, cc);
 327                         error = uiomove(buf, cc, uio);
 328                         if (error)
 329                                 break;
 330                 }
 331                 if (tp->t_canq.c_cc == 1)
 332                         (void) getc(&tp->t_canq);
 333                 if (tp->t_canq.c_cc)
 334                         goto out;
 335         } else
 336                 if (tp->t_oproc)
 337                         error = (*linesw[tp->t_line].l_read)(tp, uio, flag);
 338         ptcwakeup(tp, FWRITE);
 339 out:
 340         (void) thread_funnel_set(kernel_flock, funnel_state);
 341         return (error);
 342 }
 343
 344 /*
 345  * Write to pseudo-tty.
 346  * Wakeups of controlling tty will happen
 347  * indirectly, when tty driver calls ptsstart.
 348  */
 349 __private_extern__ int
 350 ptswrite(dev_t dev, struct uio *uio, int flag)
 351 {
 352         struct tty *tp;
 353         int error;
 354         boolean_t   funnel_state;
 355
 356         funnel_state = thread_funnel_set(kernel_flock, TRUE);
 357
 358         tp = pt_tty[minor(dev)];
 359         if (tp->t_oproc == 0)
 360                 error = EIO;
 361         else
 362                 error = (*linesw[tp->t_line].l_write)(tp, uio, flag);
 363
 364         (void) thread_funnel_set(kernel_flock, funnel_state);
 365         return (error);
 366 }
 367
 368 /*
 369  * Start output on pseudo-tty.
 370  * Wake up process selecting or sleeping for input from controlling tty.
 371  */
 372 static void
 373 ptsstart(struct tty *tp)
 374 {
 375         struct pt_ioctl *pti = &pt_ioctl[minor(tp->t_dev)];
 376         boolean_t   funnel_state;
 377
 378         funnel_state = thread_funnel_set(kernel_flock, TRUE);
 379
 380         if (tp->t_state & TS_TTSTOP)
 381                 goto out;
 382         if (pti->pt_flags & PF_STOPPED) {
 383                 pti->pt_flags &= ~PF_STOPPED;
 384                 pti->pt_send = TIOCPKT_START;
 385         }
 386         ptcwakeup(tp, FREAD);
 387 out:
 388         (void) thread_funnel_set(kernel_flock, funnel_state);
 389         return;
 390 }
 391
 392 static void
 393 ptcwakeup(struct tty *tp, int flag)
 394 {
 395         struct pt_ioctl *pti = &pt_ioctl[minor(tp->t_dev)];
 396         boolean_t   funnel_state;
 397
 398         funnel_state = thread_funnel_set(kernel_flock, TRUE);
 399
 400         if (flag & FREAD) {
 401                 selwakeup(&pti->pt_selr);
 402                 wakeup(TSA_PTC_READ(tp));
 403         }
 404         if (flag & FWRITE) {
 405                 selwakeup(&pti->pt_selw);
 406                 wakeup(TSA_PTC_WRITE(tp));
 407         }
 408         (void) thread_funnel_set(kernel_flock, funnel_state);
 409 }
 410
 411 __private_extern__ int
 412 ptcopen(dev_t dev, __unused int flag, __unused int devtype, __unused proc_t p)
 413 {
 414         struct tty *tp;
 415         struct pt_ioctl *pti;
 416         int error = 0;
 417         boolean_t   funnel_state;
 418
 419         funnel_state = thread_funnel_set(kernel_flock, TRUE);
 420
 421         if (minor(dev) >= npty) {
 422                 error = ENXIO;
 423                 goto out;
 424         }
 425         if(!pt_tty[minor(dev)]) {
 426                 tp = pt_tty[minor(dev)] = ttymalloc();
 427         } else
 428                 tp = pt_tty[minor(dev)];
 429         /* If master is open OR slave is still draining, pty is still busy */
 430         if (tp->t_oproc || (tp->t_state & TS_ISOPEN)) {
 431                 error = EBUSY;
 432                 goto out;
 433         }
 434         tp->t_oproc = ptsstart;
 435         CLR(tp->t_state, TS_ZOMBIE);
 436 #ifdef sun4c
 437         tp->t_stop = ptsstop;
 438 #endif
 439         (void)(*linesw[tp->t_line].l_modem)(tp, 1);
 440         tp->t_lflag &= ~EXTPROC;
 441         pti = &pt_ioctl[minor(dev)];
 442         pti->pt_flags = 0;
 443         pti->pt_send = 0;
 444         pti->pt_ucntl = 0;
 445 out:
 446         (void) thread_funnel_set(kernel_flock, funnel_state);
 447         return (error);
 448 }
 449
 450 __private_extern__ int
 451 ptcclose(dev_t dev, __unused int flags, __unused int fmt, __unused proc_t p)
 452 {
 453         struct tty *tp;
 454         boolean_t   funnel_state;
 455
 456         funnel_state = thread_funnel_set(kernel_flock, TRUE);
 457
 458         tp = pt_tty[minor(dev)];
 459         (void)(*linesw[tp->t_line].l_modem)(tp, 0);
 460
 461         /*
 462          * XXX MDMBUF makes no sense for ptys but would inhibit the above
 463          * l_modem().  CLOCAL makes sense but isn't supported.   Special
 464          * l_modem()s that ignore carrier drop make no sense for ptys but
 465          * may be in use because other parts of the line discipline make
 466          * sense for ptys.  Recover by doing everything that a normal
 467          * ttymodem() would have done except for sending a SIGHUP.
 468          */
 469         if (tp->t_state & TS_ISOPEN) {
 470                 tp->t_state &= ~(TS_CARR_ON | TS_CONNECTED);
 471                 tp->t_state |= TS_ZOMBIE;
 472                 ttyflush(tp, FREAD | FWRITE);
 473         }
 474
 475         tp->t_oproc = 0;                /* mark closed */
 476
 477         (void) thread_funnel_set(kernel_flock, funnel_state);
 478         return (0);
 479 }
 480
 481 __private_extern__ int
 482 ptcread(dev_t dev, struct uio *uio, int flag)
 483 {
 484         struct tty *tp = pt_tty[minor(dev)];
 485         struct pt_ioctl *pti = &pt_ioctl[minor(dev)];
 486         char buf[BUFSIZ];
 487         int error = 0, cc;
 488         boolean_t   funnel_state;
 489
 490         funnel_state = thread_funnel_set(kernel_flock, TRUE);
 491
 492         /*
 493          * We want to block until the slave
 494          * is open, and there's something to read;
 495          * but if we lost the slave or we're NBIO,
 496          * then return the appropriate error instead.
 497          */
 498         for (;;) {
 499                 if (tp->t_state&TS_ISOPEN) {
 500                         if (pti->pt_flags&PF_PKT && pti->pt_send) {
 501                                 error = ureadc((int)pti->pt_send, uio);
 502                                 if (error)
 503                                         goto out;
 504                                 if (pti->pt_send & TIOCPKT_IOCTL) {
 505                                         cc = min(uio_resid(uio),
 506                                                 sizeof(tp->t_termios));
 507                                         uiomove((caddr_t)&tp->t_termios, cc,
 508                                                 uio);
 509                                 }
 510                                 pti->pt_send = 0;
 511                                 goto out;
 512                         }
 513                         if (pti->pt_flags&PF_UCNTL && pti->pt_ucntl) {
 514                                 error = ureadc((int)pti->pt_ucntl, uio);
 515                                 if (error)
 516                                         goto out;
 517                                 pti->pt_ucntl = 0;
 518                                 goto out;
 519                         }
 520                         if (tp->t_outq.c_cc && (tp->t_state&TS_TTSTOP) == 0)
 521                                 break;
 522                 }
 523                 if ((tp->t_state & TS_CONNECTED) == 0)
 524                         goto out;       /* EOF */
 525                 if (flag & IO_NDELAY) {
 526                         error = EWOULDBLOCK;
 527                         goto out;
 528                 }
 529                 error = tsleep(TSA_PTC_READ(tp), TTIPRI | PCATCH, "ptcin", 0);
 530                 if (error)
 531                         goto out;
 532         }
 533         if (pti->pt_flags & (PF_PKT|PF_UCNTL))
 534                 error = ureadc(0, uio);
 535         while (uio_resid(uio) > 0 && error == 0) {
 536                 cc = q_to_b(&tp->t_outq, (u_char *)buf, min(uio_resid(uio), BUFSIZ));
 537                 if (cc <= 0)
 538                         break;
 539                 error = uiomove(buf, cc, uio);
 540         }
 541         (*linesw[tp->t_line].l_start)(tp);
 542
 543 out:
 544         (void) thread_funnel_set(kernel_flock, funnel_state);
 545         return (error);
 546 }
 547
 548 __private_extern__ void
 549 ptsstop(struct tty *tp, int flush)
 550 {
 551         struct pt_ioctl *pti = &pt_ioctl[minor(tp->t_dev)];
 552         int flag;
 553         boolean_t   funnel_state;
 554
 555         funnel_state = thread_funnel_set(kernel_flock, TRUE);
 556
 557         /* note: FLUSHREAD and FLUSHWRITE already ok */
 558         if (flush == 0) {
 559                 flush = TIOCPKT_STOP;
 560                 pti->pt_flags |= PF_STOPPED;
 561         } else
 562                 pti->pt_flags &= ~PF_STOPPED;
 563         pti->pt_send |= flush;
 564         /* change of perspective */
 565         flag = 0;
 566         if (flush & FREAD)
 567                 flag |= FWRITE;
 568         if (flush & FWRITE)
 569                 flag |= FREAD;
 570         ptcwakeup(tp, flag);
 571
 572         (void) thread_funnel_set(kernel_flock, funnel_state);
 573 }
 574
 575 __private_extern__ int
 576 ptcselect(dev_t dev, int rw, void *wql, struct proc *p)
 577 {
 578         struct tty *tp = pt_tty[minor(dev)];
 579         struct pt_ioctl *pti = &pt_ioctl[minor(dev)];
 580         int retval = 0;
 581         boolean_t   funnel_state;
 582
 583         funnel_state = thread_funnel_set(kernel_flock, TRUE);
 584
 585         if ((tp->t_state & TS_CONNECTED) == 0) {
 586                 retval = 1;
 587                 goto out;
 588         }
 589         switch (rw) {
 590
 591         case FREAD:
 592                 /*
 593                  * Need to block timeouts (ttrstart).
 594                  */
 595                 if ((tp->t_state&TS_ISOPEN) &&
 596                      tp->t_outq.c_cc && (tp->t_state&TS_TTSTOP) == 0) {
 597                         retval = 1;
 598                         goto out;
 599                 }
 600                 /* FALLTHROUGH */
 601
 602         case 0:                                 /* exceptional */
 603                 if ((tp->t_state&TS_ISOPEN) &&
 604                     ((pti->pt_flags&PF_PKT && pti->pt_send) ||
 605                      (pti->pt_flags&PF_UCNTL && pti->pt_ucntl))) {
 606                         retval = 1;
 607                         goto out;
 608                 }
 609                 selrecord(p, &pti->pt_selr, wql);
 610                 break;
 611
 612
 613         case FWRITE:
 614                 if (tp->t_state&TS_ISOPEN) {
 615                         if (pti->pt_flags & PF_REMOTE) {
 616                             if (tp->t_canq.c_cc == 0) {
 617                                 retval = 1;
 618                                 goto out;
 619                             }
 620                         } else {
 621                             if (tp->t_rawq.c_cc + tp->t_canq.c_cc < TTYHOG-2) {
 622                                     retval = 1;
 623                                     goto out;
 624                             }
 625                             if (tp->t_canq.c_cc == 0 && (tp->t_lflag&ICANON)) {
 626                                     retval = 1;
 627                                     goto out;
 628                             }
 629                         }
 630                 }
 631                 selrecord(p, &pti->pt_selw, wql);
 632                 break;
 633
 634         }
 635 out:
 636         (void) thread_funnel_set(kernel_flock, funnel_state);
 637         return (retval);
 638 }
 639
 640 __private_extern__ int
 641 ptcwrite(dev_t dev, struct uio *uio, int flag)
 642 {
 643         struct tty *tp = pt_tty[minor(dev)];
 644         u_char *cp = NULL;
 645         int cc = 0;
 646         u_char locbuf[BUFSIZ];
 647         int wcnt = 0;
 648         struct pt_ioctl *pti = &pt_ioctl[minor(dev)];
 649         int error = 0;
 650         boolean_t   funnel_state;
 651
 652         funnel_state = thread_funnel_set(kernel_flock, TRUE);
 653
 654 again:
 655         if ((tp->t_state&TS_ISOPEN) == 0)
 656                 goto block;
 657         if (pti->pt_flags & PF_REMOTE) {
 658                 if (tp->t_canq.c_cc)
 659                         goto block;
 660                 while ((uio_resid(uio) > 0 || cc > 0) &&
 661                        tp->t_canq.c_cc < TTYHOG - 1) {
 662                         if (cc == 0) {
 663                                 cc = min(uio_resid(uio), BUFSIZ);
 664                                 cc = min(cc, TTYHOG - 1 - tp->t_canq.c_cc);
 665                                 cp = locbuf;
 666                                 error = uiomove((caddr_t)cp, cc, uio);
 667                                 if (error)
 668                                         goto out;
 669                                 /* check again for safety */
 670                                 if ((tp->t_state & TS_ISOPEN) == 0) {
 671                                         /* adjust as usual */
 672                                         uio_setresid(uio, (uio_resid(uio) + cc));
 673                                         error = EIO;
 674                                         goto out;
 675                                 }
 676                         }
 677                         if (cc > 0) {
 678                                 cc = b_to_q((u_char *)cp, cc, &tp->t_canq);
 679                                 /*
 680                                  * XXX we don't guarantee that the canq size
 681                                  * is >= TTYHOG, so the above b_to_q() may
 682                                  * leave some bytes uncopied.  However, space
 683                                  * is guaranteed for the null terminator if
 684                                  * we don't fail here since (TTYHOG - 1) is
 685                                  * not a multiple of CBSIZE.
 686                                  */
 687                                 if (cc > 0)
 688                                         break;
 689                         }
 690                 }
 691                 /* adjust for data copied in but not written */
 692                 uio_setresid(uio, (uio_resid(uio) + cc));
 693                 (void) putc(0, &tp->t_canq);
 694                 ttwakeup(tp);
 695                 wakeup(TSA_PTS_READ(tp));
 696                 goto out;
 697         }
 698         while (uio_resid(uio) > 0 || cc > 0) {
 699                 if (cc == 0) {
 700                         cc = min(uio_resid(uio), BUFSIZ);
 701                         cp = locbuf;
 702                         error = uiomove((caddr_t)cp, cc, uio);
 703                         if (error)
 704                                 goto out;
 705                         /* check again for safety */
 706                         if ((tp->t_state & TS_ISOPEN) == 0) {
 707                                 /* adjust for data copied in but not written */
 708                                 uio_setresid(uio, (uio_resid(uio) + cc));
 709                                 error = EIO;
 710                                 goto out;
 711                         }
 712                 }
 713                 while (cc > 0) {
 714                         if ((tp->t_rawq.c_cc + tp->t_canq.c_cc) >= TTYHOG - 2 &&
 715                            (tp->t_canq.c_cc > 0 || !(tp->t_lflag&ICANON))) {
 716                                 wakeup(TSA_HUP_OR_INPUT(tp));
 717                                 goto block;
 718                         }
 719                         (*linesw[tp->t_line].l_rint)(*cp++, tp);
 720                         wcnt++;
 721                         cc--;
 722                 }
 723                 cc = 0;
 724         }
 725 out:
 726         (void) thread_funnel_set(kernel_flock, funnel_state);
 727         return (error);
 728 block:
 729         /*
 730          * Come here to wait for slave to open, for space
 731          * in outq, or space in rawq, or an empty canq.
 732          */
 733         if ((tp->t_state & TS_CONNECTED) == 0) {
 734                 /* adjust for data copied in but not written */
 735                 uio_setresid(uio, (uio_resid(uio) + cc));
 736                 error = EIO;
 737                 goto out;
 738         }
 739         if (flag & IO_NDELAY) {
 740                 /* adjust for data copied in but not written */
 741                 uio_setresid(uio, (uio_resid(uio) + cc));
 742                 if (wcnt == 0)
 743                         error = EWOULDBLOCK;
 744                 goto out;
 745         }
 746         error = tsleep(TSA_PTC_WRITE(tp), TTOPRI | PCATCH, "ptcout", 0);
 747         if (error) {
 748                 /* adjust for data copied in but not written */
 749                 uio_setresid(uio, (uio_resid(uio) + cc));
 750                 goto out;
 751         }
 752         goto again;
 753 }
 754
 755 __private_extern__ int
 756 ptyioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct proc *p)
 757 {
 758         struct tty *tp = pt_tty[minor(dev)];
 759         struct pt_ioctl *pti = &pt_ioctl[minor(dev)];
 760         u_char *cc = tp->t_cc;
 761         int stop, error = 0;
 762         boolean_t   funnel_state;
 763
 764         funnel_state = thread_funnel_set(kernel_flock, TRUE);
 765
 766         /*
 767          * IF CONTROLLER STTY THEN MUST FLUSH TO PREVENT A HANG.
 768          * ttywflush(tp) will hang if there are characters in the outq.
 769          */
 770         if (cmd == TIOCEXT) {
 771                 /*
 772                  * When the EXTPROC bit is being toggled, we need
 773                  * to send an TIOCPKT_IOCTL if the packet driver
 774                  * is turned on.
 775                  */
 776                 if (*(int *)data) {
 777                         if (pti->pt_flags & PF_PKT) {
 778                                 pti->pt_send |= TIOCPKT_IOCTL;
 779                                 ptcwakeup(tp, FREAD);
 780                         }
 781                         tp->t_lflag |= EXTPROC;
 782                 } else {
 783                         if ((tp->t_lflag & EXTPROC) &&
 784                             (pti->pt_flags & PF_PKT)) {
 785                                 pti->pt_send |= TIOCPKT_IOCTL;
 786                                 ptcwakeup(tp, FREAD);
 787                         }
 788                         tp->t_lflag &= ~EXTPROC;
 789                 }
 790                 goto out;
 791         } else
 792         if (cdevsw[major(dev)].d_open == ptcopen)
 793                 switch (cmd) {
 794
 795                 case TIOCGPGRP:
 796                         /*
 797                          * We aviod calling ttioctl on the controller since,
 798                          * in that case, tp must be the controlling terminal.
 799                          */
 800                         *(int *)data = tp->t_pgrp ? tp->t_pgrp->pg_id : 0;
 801                         goto out;
 802
 803                 case TIOCPKT:
 804                         if (*(int *)data) {
 805                                 if (pti->pt_flags & PF_UCNTL) {
 806                                         error = EINVAL;
 807                                         goto out;
 808                                 }
 809                                 pti->pt_flags |= PF_PKT;
 810                         } else
 811                                 pti->pt_flags &= ~PF_PKT;
 812                         goto out;
 813
 814                 case TIOCUCNTL:
 815                         if (*(int *)data) {
 816                                 if (pti->pt_flags & PF_PKT) {
 817                                         error = EINVAL;
 818                                         goto out;
 819                                 }
 820                                 pti->pt_flags |= PF_UCNTL;
 821                         } else
 822                                 pti->pt_flags &= ~PF_UCNTL;
 823                         goto out;
 824
 825                 case TIOCREMOTE:
 826                         if (*(int *)data)
 827                                 pti->pt_flags |= PF_REMOTE;
 828                         else
 829                                 pti->pt_flags &= ~PF_REMOTE;
 830                         ttyflush(tp, FREAD|FWRITE);
 831                         goto out;
 832
 833 #if COMPAT_43_TTY
 834                 case TIOCSETP:
 835                 case TIOCSETN:
 836 #endif
 837                 case TIOCSETD:
 838                 case TIOCSETA:
 839                 case TIOCSETAW:
 840                 case TIOCSETAF:
 841                         ndflush(&tp->t_outq, tp->t_outq.c_cc);
 842                         break;
 843
 844                 case TIOCSIG:
 845                         if (*(unsigned int *)data >= NSIG ||
 846                             *(unsigned int *)data == 0) {
 847                                 error = EINVAL;
 848                                 goto out;
 849                         }
 850                         if ((tp->t_lflag&NOFLSH) == 0)
 851                                 ttyflush(tp, FREAD|FWRITE);
 852                         tty_pgsignal(tp, *(unsigned int *)data, 1);
 853                         if ((*(unsigned int *)data == SIGINFO) &&
 854                             ((tp->t_lflag&NOKERNINFO) == 0))
 855                                 ttyinfo(tp);
 856                         goto out;
 857
 858                 case TIOCPTYGRANT:      /* grantpt(3) */
 859                         /*
 860                          * Change the uid of the slave to that of the calling
 861                          * thread, change the gid of the slave to GID_TTY,
 862                          * change the mode to 0620 (rw--w----).
 863                          */
 864                         {
 865                                 _devfs_setattr(pti->pt_devhandle, 0620, kauth_getuid(), GID_TTY);
 866                                 goto out;
 867                         }
 868
 869                 case TIOCPTYGNAME:      /* ptsname(3) */
 870                         /*
 871                          * Report the name of the slave device in *data
 872                          * (128 bytes max.).  Use the same derivation method
 873                          * used for calling devfs_make_node() to create it.
 874                          */
 875                         snprintf(data, 128, "/dev/tty%c%x",
 876                                 START_CHAR + (minor(dev) / HEX_BASE),
 877                                 minor(dev) % HEX_BASE);
 878                         error = 0;
 879                         goto out;
 880
 881                 case TIOCPTYUNLK:       /* unlockpt(3) */
 882                         /*
 883                          * Unlock the slave device so that it can be opened.
 884                          */
 885                         error = 0;
 886                         goto out;
 887                 }
 888         error = (*linesw[tp->t_line].l_ioctl)(tp, cmd, data, flag, p);
 889         if (error == ENOTTY) {
 890                 error = ttioctl(tp, cmd, data, flag, p);
 891                 if (error == ENOTTY) {
 892                         if (pti->pt_flags & PF_UCNTL && (cmd & ~0xff) == UIOCCMD(0)) {
 893                                 /* Process the UIOCMD ioctl group */
 894                                 if (cmd & 0xff) {
 895                                         pti->pt_ucntl = (u_char)cmd;
 896                                         ptcwakeup(tp, FREAD);
 897                                 }
 898                                 error = 0;
 899                                 goto out;
 900                         } else if (cmd == TIOCSBRK || cmd == TIOCCBRK) {
 901                                 /*
 902                                  * POSIX conformance; rdar://3936338
 903                                  *
 904                                  * Clear ENOTTY in the case of setting or
 905                                  * clearing a break failing because pty's
 906                                  * don't support break like real serial
 907                                  * ports.
 908                                  */
 909                                 error = 0;
 910                                 goto out;
 911                         }
 912                 }
 913         }
 914
 915         /*
 916          * If external processing and packet mode send ioctl packet.
 917          */
 918         if ((tp->t_lflag&EXTPROC) && (pti->pt_flags & PF_PKT)) {
 919                 switch(cmd) {
 920                 case TIOCSETA:
 921                 case TIOCSETAW:
 922                 case TIOCSETAF:
 923 #if COMPAT_43_TTY
 924                 case TIOCSETP:
 925                 case TIOCSETN:
 926 #endif
 927 #if COMPAT_43_TTY || defined(COMPAT_SUNOS)
 928                 case TIOCSETC:
 929                 case TIOCSLTC:
 930                 case TIOCLBIS:
 931                 case TIOCLBIC:
 932                 case TIOCLSET:
 933 #endif
 934                         pti->pt_send |= TIOCPKT_IOCTL;
 935                         ptcwakeup(tp, FREAD);
 936                 default:
 937                         break;
 938                 }
 939         }
 940         stop = (tp->t_iflag & IXON) && CCEQ(cc[VSTOP], CTRL('s'))
 941                 && CCEQ(cc[VSTART], CTRL('q'));
 942         if (pti->pt_flags & PF_NOSTOP) {
 943                 if (stop) {
 944                         pti->pt_send &= ~TIOCPKT_NOSTOP;
 945                         pti->pt_send |= TIOCPKT_DOSTOP;
 946                         pti->pt_flags &= ~PF_NOSTOP;
 947                         ptcwakeup(tp, FREAD);
 948                 }
 949         } else {
 950                 if (!stop) {
 951                         pti->pt_send &= ~TIOCPKT_DOSTOP;
 952                         pti->pt_send |= TIOCPKT_NOSTOP;
 953                         pti->pt_flags |= PF_NOSTOP;
 954                         ptcwakeup(tp, FREAD);
 955                 }
 956         }
 957 out:
 958         (void) thread_funnel_set(kernel_flock, funnel_state);
 959         return (error);
 960 }