The Design and Implementation of the FreeBSD Operating System, Second Edition
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FreeBSD/Linux Kernel Cross Reference
sys/kern/tty_pty.c

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    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  * 4. Neither the name of the University nor the names of its contributors
   14  *    may be used to endorse or promote products derived from this software
   15  *    without specific prior written permission.
   16  *
   17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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  *      @(#)tty_pty.c   8.4 (Berkeley) 2/20/95
   30  */
   31 
   32 #include <sys/cdefs.h>
   33 __FBSDID("$FreeBSD: releng/7.3/sys/kern/tty_pty.c 181764 2008-08-15 19:25:40Z jhb $");
   34 
   35 /*
   36  * Pseudo-teletype Driver
   37  * (Actually two drivers, requiring two entries in 'cdevsw')
   38  */
   39 #include "opt_compat.h"
   40 #include "opt_tty.h"
   41 #include <sys/param.h>
   42 #include <sys/systm.h>
   43 #include <sys/libkern.h>
   44 #include <sys/lock.h>
   45 #include <sys/mutex.h>
   46 #include <sys/sx.h>
   47 #if defined(COMPAT_43TTY)
   48 #include <sys/ioctl_compat.h>
   49 #endif
   50 #include <sys/priv.h>
   51 #include <sys/proc.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/uio.h>
   58 #include <sys/signalvar.h>
   59 #include <sys/malloc.h>
   60 
   61 static MALLOC_DEFINE(M_PTY, "ptys", "pty data structures");
   62 
   63 static void ptsstart(struct tty *tp);
   64 static void ptsstop(struct tty *tp, int rw);
   65 static void ptcwakeup(struct tty *tp, int flag);
   66 static struct cdev *ptyinit(struct cdev *cdev, struct thread *td);
   67 
   68 static  d_open_t        ptsopen;
   69 static  d_close_t       ptsclose;
   70 static  d_read_t        ptsread;
   71 static  d_write_t       ptswrite;
   72 static  d_ioctl_t       ptsioctl;
   73 static  d_open_t        ptcopen;
   74 static  d_close_t       ptcclose;
   75 static  d_read_t        ptcread;
   76 static  d_ioctl_t       ptcioctl;
   77 static  d_write_t       ptcwrite;
   78 static  d_poll_t        ptcpoll;
   79 
   80 static struct cdevsw pts_cdevsw = {
   81         .d_version =    D_VERSION,
   82         .d_open =       ptsopen,
   83         .d_close =      ptsclose,
   84         .d_read =       ptsread,
   85         .d_write =      ptswrite,
   86         .d_ioctl =      ptsioctl,
   87         .d_name =       "pts",
   88         .d_flags =      D_TTY | D_NEEDGIANT,
   89 };
   90 
   91 static struct cdevsw ptc_cdevsw = {
   92         .d_version =    D_VERSION,
   93         .d_open =       ptcopen,
   94         .d_close =      ptcclose,
   95         .d_read =       ptcread,
   96         .d_write =      ptcwrite,
   97         .d_ioctl =      ptcioctl,
   98         .d_poll =       ptcpoll,
   99         .d_name =       "ptc",
  100         .d_flags =      D_TTY | D_NEEDGIANT,
  101 };
  102 
  103 static struct mtx ptyinit_lock;
  104 MTX_SYSINIT(ptyinit_lock, &ptyinit_lock, "ptyinit", MTX_DEF);
  105 
  106 #define BUFSIZ 100              /* Chunk size iomoved to/from user */
  107 
  108 struct  ptsc {
  109         int     pt_flags;
  110         struct  selinfo pt_selr, pt_selw;
  111         u_char  pt_send;
  112         u_char  pt_ucntl;
  113         struct tty *pt_tty;
  114         struct cdev *devs, *devc;
  115         int     pt_devs_open, pt_devc_open;
  116         struct  prison *pt_prison;
  117 };
  118 
  119 #define PF_PKT          0x08            /* packet mode */
  120 #define PF_STOPPED      0x10            /* user told stopped */
  121 #define PF_NOSTOP       0x40
  122 #define PF_UCNTL        0x80            /* user control mode */
  123 
  124 #define TSA_PTC_READ(tp)        ((void *)&(tp)->t_outq.c_cf)
  125 #define TSA_PTC_WRITE(tp)       ((void *)&(tp)->t_rawq.c_cl)
  126 #define TSA_PTS_READ(tp)        ((void *)&(tp)->t_canq)
  127 
  128 static const char names[] = "pqrsPQRSlmnoLMNO";
  129 /*
  130  * This function creates and initializes a pts/ptc pair
  131  *
  132  * pts == /dev/tty[pqrsPQRSlmnoLMNO][0123456789abcdefghijklmnopqrstuv]
  133  * ptc == /dev/pty[pqrsPQRSlmnoLMNO][0123456789abcdefghijklmnopqrstuv]
  134  */
  135 static struct cdev *
  136 ptyinit(struct cdev *devc, struct thread *td)
  137 {
  138         struct ptsc *pt;
  139         int n;
  140 
  141         n = minor2unit(minor(devc));
  142 
  143         /* We only allow for up to 32 ptys per char in "names". */
  144         if (n >= 32 * (sizeof(names) - 1))
  145                 return (NULL);
  146 
  147         devc->si_flags &= ~SI_CHEAPCLONE;
  148 
  149         /*
  150          * Initially do not create a slave endpoint.
  151          */
  152         pt = malloc(sizeof(*pt), M_PTY, M_WAITOK | M_ZERO);
  153         pt->devc = devc;
  154 
  155         pt->pt_tty = ttyalloc();
  156         pt->pt_tty->t_sc = pt;
  157         mtx_lock(&ptyinit_lock);
  158         if (devc->si_drv1 == NULL) {
  159                 devc->si_drv1 = pt;
  160                 devc->si_tty = pt->pt_tty;
  161                 mtx_unlock(&ptyinit_lock);
  162         } else {
  163                 mtx_unlock(&ptyinit_lock);
  164                 ttyrel(pt->pt_tty);
  165                 free(pt, M_PTY);
  166         }
  167         return (devc);
  168 }
  169 
  170 static void
  171 pty_create_slave(struct ucred *cred, struct ptsc *pt, int m)
  172 {
  173         int n;
  174 
  175         n = minor2unit(m);
  176         KASSERT(n >= 0 && n / 32 < sizeof(names),
  177             ("pty_create_slave: n %d ptsc %p", n, pt));
  178         pt->devs = make_dev_cred(&pts_cdevsw, m, cred, UID_ROOT, GID_WHEEL,
  179             0666, "tty%c%r", names[n / 32], n % 32);
  180         pt->devs->si_drv1 = pt;
  181         pt->devs->si_tty = pt->pt_tty;
  182         pt->pt_tty->t_dev = pt->devs;
  183 }
  184 
  185 static void
  186 pty_destroy_slave(struct ptsc *pt)
  187 {
  188 
  189         if (pt->pt_tty->t_refcnt > 1)
  190                 return;
  191         pt->pt_tty->t_dev = NULL;
  192         ttyrel(pt->pt_tty);
  193         pt->pt_tty = NULL;
  194         destroy_dev(pt->devs);
  195         pt->devs = NULL;
  196 }
  197 
  198 static void
  199 pty_maybe_destroy_slave(struct ptsc *pt)
  200 {
  201 
  202         /*
  203          * vfs bugs and complications near revoke() make
  204          * it currently impossible to destroy struct cdev
  205          */
  206         if (0 && pt->pt_devc_open == 0 && pt->pt_devs_open == 0)
  207                 pty_destroy_slave(pt);
  208 }
  209 
  210 /*ARGSUSED*/
  211 static  int
  212 ptsopen(struct cdev *dev, int flag, int devtype, struct thread *td)
  213 {
  214         struct tty *tp;
  215         int error;
  216         struct ptsc *pt;
  217 
  218         if (!dev->si_drv1)
  219                 return(ENXIO);
  220         pt = dev->si_drv1;
  221         tp = dev->si_tty;
  222 
  223         if ((tp->t_state & TS_ISOPEN) == 0) {
  224                 ttyinitmode(tp, 1, 0);
  225         } else if (tp->t_state & TS_XCLUDE && priv_check(td,
  226             PRIV_TTY_EXCLUSIVE))
  227                 return (EBUSY);
  228         else if (pt->pt_prison != td->td_ucred->cr_prison &&
  229             priv_check(td, PRIV_TTY_PRISON))
  230                 return (EBUSY);
  231         if (tp->t_oproc)                        /* Ctrlr still around. */
  232                 (void)ttyld_modem(tp, 1);
  233         while ((tp->t_state & TS_CARR_ON) == 0) {
  234                 if (flag&FNONBLOCK)
  235                         break;
  236                 error = ttysleep(tp, TSA_CARR_ON(tp), TTIPRI | PCATCH,
  237                                  "ptsopn", 0);
  238                 if (error)
  239                         return (error);
  240         }
  241         error = ttyld_open(tp, dev);
  242         if (error == 0) {
  243                 ptcwakeup(tp, FREAD|FWRITE);
  244                 pt->pt_devs_open = 1;
  245         } else
  246                 pty_maybe_destroy_slave(pt);
  247         return (error);
  248 }
  249 
  250 static  int
  251 ptsclose(struct cdev *dev, int flag, int mode, struct thread *td)
  252 {
  253         struct ptsc *pti;
  254         struct tty *tp;
  255         int err;
  256 
  257         tp = dev->si_tty;
  258         pti = dev->si_drv1;
  259 
  260         KASSERT(dev == pti->devs, ("ptsclose: dev != pti->devs"));
  261 
  262         err = ttyld_close(tp, flag);
  263         (void) tty_close(tp);
  264 
  265         pti->pt_devs_open = 0;
  266         pty_maybe_destroy_slave(pti);
  267 
  268         return (err);
  269 }
  270 
  271 static  int
  272 ptsread(struct cdev *dev, struct uio *uio, int flag)
  273 {
  274         struct tty *tp = dev->si_tty;
  275         int error = 0;
  276 
  277         if (tp->t_oproc)
  278                 error = ttyld_read(tp, uio, flag);
  279         ptcwakeup(tp, FWRITE);
  280         return (error);
  281 }
  282 
  283 /*
  284  * Write to pseudo-tty.
  285  * Wakeups of controlling tty will happen
  286  * indirectly, when tty driver calls ptsstart.
  287  */
  288 static  int
  289 ptswrite(struct cdev *dev, struct uio *uio, int flag)
  290 {
  291         struct tty *tp;
  292 
  293         tp = dev->si_tty;
  294         if (tp->t_oproc == 0)
  295                 return (EIO);
  296         return (ttyld_write(tp, uio, flag));
  297 }
  298 
  299 /*
  300  * Start output on pseudo-tty.
  301  * Wake up process selecting or sleeping for input from controlling tty.
  302  */
  303 static void
  304 ptsstart(struct tty *tp)
  305 {
  306         struct ptsc *pt = tp->t_sc;
  307 
  308         if (tp->t_state & TS_TTSTOP)
  309                 return;
  310         if (pt->pt_flags & PF_STOPPED) {
  311                 pt->pt_flags &= ~PF_STOPPED;
  312                 pt->pt_send = TIOCPKT_START;
  313         }
  314         ptcwakeup(tp, FREAD);
  315 }
  316 
  317 static void
  318 ptcwakeup(struct tty *tp, int flag)
  319 {
  320         struct ptsc *pt = tp->t_sc;
  321 
  322         if (flag & FREAD) {
  323                 selwakeuppri(&pt->pt_selr, TTIPRI);
  324                 wakeup(TSA_PTC_READ(tp));
  325         }
  326         if (flag & FWRITE) {
  327                 selwakeuppri(&pt->pt_selw, TTOPRI);
  328                 wakeup(TSA_PTC_WRITE(tp));
  329         }
  330 }
  331 
  332 static  int
  333 ptcopen(struct cdev *dev, int flag, int devtype, struct thread *td)
  334 {
  335         struct tty *tp;
  336         struct ptsc *pt;
  337 
  338         if (!dev->si_drv1)
  339                 ptyinit(dev, td);
  340         if (!dev->si_drv1)
  341                 return(ENXIO);
  342 
  343         pt = dev->si_drv1;
  344         /*
  345          * In case we have destroyed the struct tty at the last connect time,
  346          * we need to recreate it.
  347          */
  348         if (pt->pt_tty == NULL) {
  349                 tp = ttyalloc();
  350                 mtx_lock(&ptyinit_lock);
  351                 if (pt->pt_tty == NULL) {
  352                         pt->pt_tty = tp;
  353                         pt->pt_tty->t_sc = pt;
  354                         dev->si_tty = pt->pt_tty;
  355                         mtx_unlock(&ptyinit_lock);
  356                 } else {
  357                         mtx_unlock(&ptyinit_lock);
  358                         ttyrel(tp);
  359                 }
  360         }
  361         tp = dev->si_tty;
  362 
  363         if (tp->t_oproc)
  364                 return (EIO);
  365         tp->t_timeout = -1;
  366         tp->t_oproc = ptsstart;
  367         tp->t_stop = ptsstop;
  368         (void)ttyld_modem(tp, 1);
  369         tp->t_lflag &= ~EXTPROC;
  370         pt->pt_prison = td->td_ucred->cr_prison;
  371         pt->pt_flags = 0;
  372         pt->pt_send = 0;
  373         pt->pt_ucntl = 0;
  374 
  375         if (!pt->devs)
  376                 pty_create_slave(td->td_ucred, pt, minor(dev));
  377         pt->pt_devc_open = 1;
  378 
  379         return (0);
  380 }
  381 
  382 static  int
  383 ptcclose(struct cdev *dev, int flags, int fmt, struct thread *td)
  384 {
  385         struct ptsc *pti = dev->si_drv1;
  386         struct tty *tp;
  387 
  388         tp = dev->si_tty;
  389         (void)ttyld_modem(tp, 0);
  390 
  391         /*
  392          * XXX MDMBUF makes no sense for ptys but would inhibit the above
  393          * l_modem().  CLOCAL makes sense but isn't supported.   Special
  394          * l_modem()s that ignore carrier drop make no sense for ptys but
  395          * may be in use because other parts of the line discipline make
  396          * sense for ptys.  Recover by doing everything that a normal
  397          * ttymodem() would have done except for sending a SIGHUP.
  398          */
  399         if (tp->t_state & TS_ISOPEN) {
  400                 tp->t_state &= ~(TS_CARR_ON | TS_CONNECTED);
  401                 tp->t_state |= TS_ZOMBIE;
  402                 ttyflush(tp, FREAD | FWRITE);
  403         }
  404 
  405         tp->t_oproc = 0;                /* mark closed */
  406         pti->pt_devc_open = 0;
  407         pty_maybe_destroy_slave(pti);
  408         return (0);
  409 }
  410 
  411 static  int
  412 ptcread(struct cdev *dev, struct uio *uio, int flag)
  413 {
  414         struct tty *tp = dev->si_tty;
  415         struct ptsc *pt = dev->si_drv1;
  416         char buf[BUFSIZ];
  417         int error = 0, cc;
  418 
  419         /*
  420          * We want to block until the slave
  421          * is open, and there's something to read;
  422          * but if we lost the slave or we're NBIO,
  423          * then return the appropriate error instead.
  424          */
  425         for (;;) {
  426                 if (tp->t_state&TS_ISOPEN) {
  427                         if (pt->pt_flags&PF_PKT && pt->pt_send) {
  428                                 error = ureadc((int)pt->pt_send, uio);
  429                                 if (error)
  430                                         return (error);
  431                                 if (pt->pt_send & TIOCPKT_IOCTL) {
  432                                         cc = min(uio->uio_resid,
  433                                                 sizeof(tp->t_termios));
  434                                         uiomove(&tp->t_termios, cc, uio);
  435                                 }
  436                                 pt->pt_send = 0;
  437                                 return (0);
  438                         }
  439                         if (pt->pt_flags&PF_UCNTL && pt->pt_ucntl) {
  440                                 error = ureadc((int)pt->pt_ucntl, uio);
  441                                 if (error)
  442                                         return (error);
  443                                 pt->pt_ucntl = 0;
  444                                 return (0);
  445                         }
  446                         if (tp->t_outq.c_cc && (tp->t_state&TS_TTSTOP) == 0)
  447                                 break;
  448                 }
  449                 if ((tp->t_state & TS_CONNECTED) == 0)
  450                         return (0);     /* EOF */
  451                 if (flag & O_NONBLOCK)
  452                         return (EWOULDBLOCK);
  453                 error = tsleep(TSA_PTC_READ(tp), TTIPRI | PCATCH, "ptcin", 0);
  454                 if (error)
  455                         return (error);
  456         }
  457         if (pt->pt_flags & (PF_PKT|PF_UCNTL))
  458                 error = ureadc(0, uio);
  459         while (uio->uio_resid > 0 && error == 0) {
  460                 cc = q_to_b(&tp->t_outq, buf, min(uio->uio_resid, BUFSIZ));
  461                 if (cc <= 0)
  462                         break;
  463                 error = uiomove(buf, cc, uio);
  464         }
  465         ttwwakeup(tp);
  466         return (error);
  467 }
  468 
  469 static  void
  470 ptsstop(struct tty *tp, int flush)
  471 {
  472         struct ptsc *pt = tp->t_sc;
  473         int flag;
  474 
  475         /* note: FLUSHREAD and FLUSHWRITE already ok */
  476         if (flush == 0) {
  477                 flush = TIOCPKT_STOP;
  478                 pt->pt_flags |= PF_STOPPED;
  479         } else
  480                 pt->pt_flags &= ~PF_STOPPED;
  481         pt->pt_send |= flush;
  482         /* change of perspective */
  483         flag = 0;
  484         if (flush & FREAD)
  485                 flag |= FWRITE;
  486         if (flush & FWRITE)
  487                 flag |= FREAD;
  488         ptcwakeup(tp, flag);
  489 }
  490 
  491 static  int
  492 ptcpoll(struct cdev *dev, int events, struct thread *td)
  493 {
  494         struct tty *tp = dev->si_tty;
  495         struct ptsc *pt = dev->si_drv1;
  496         int revents = 0;
  497         int s;
  498 
  499         if ((tp->t_state & TS_CONNECTED) == 0)
  500                 return (events & 
  501                    (POLLHUP | POLLIN | POLLRDNORM | POLLOUT | POLLWRNORM));
  502 
  503         /*
  504          * Need to block timeouts (ttrstart).
  505          */
  506         s = spltty();
  507 
  508         if (events & (POLLIN | POLLRDNORM))
  509                 if ((tp->t_state & TS_ISOPEN) &&
  510                     ((tp->t_outq.c_cc && (tp->t_state & TS_TTSTOP) == 0) ||
  511                      ((pt->pt_flags & PF_PKT) && pt->pt_send) ||
  512                      ((pt->pt_flags & PF_UCNTL) && pt->pt_ucntl)))
  513                         revents |= events & (POLLIN | POLLRDNORM);
  514 
  515         if (events & (POLLOUT | POLLWRNORM))
  516                 if (tp->t_state & TS_ISOPEN &&
  517                     (((tp->t_rawq.c_cc + tp->t_canq.c_cc < TTYHOG - 2) ||
  518                       (tp->t_canq.c_cc == 0 && (tp->t_lflag & ICANON)))))
  519                         revents |= events & (POLLOUT | POLLWRNORM);
  520 
  521         if (events & POLLHUP)
  522                 if ((tp->t_state & TS_CARR_ON) == 0)
  523                         revents |= POLLHUP;
  524 
  525         if (revents == 0) {
  526                 if (events & (POLLIN | POLLRDNORM))
  527                         selrecord(td, &pt->pt_selr);
  528 
  529                 if (events & (POLLOUT | POLLWRNORM))
  530                         selrecord(td, &pt->pt_selw);
  531         }
  532         splx(s);
  533 
  534         return (revents);
  535 }
  536 
  537 static  int
  538 ptcwrite(struct cdev *dev, struct uio *uio, int flag)
  539 {
  540         struct tty *tp = dev->si_tty;
  541         u_char *cp = 0;
  542         int cc = 0;
  543         u_char locbuf[BUFSIZ];
  544         int cnt = 0;
  545         int error = 0;
  546 
  547 again:
  548         if ((tp->t_state&TS_ISOPEN) == 0)
  549                 goto block;
  550         while (uio->uio_resid > 0 || cc > 0) {
  551                 if (cc == 0) {
  552                         cc = min(uio->uio_resid, BUFSIZ);
  553                         cp = locbuf;
  554                         error = uiomove(cp, cc, uio);
  555                         if (error)
  556                                 return (error);
  557                         /* check again for safety */
  558                         if ((tp->t_state & TS_ISOPEN) == 0) {
  559                                 /* adjust for data copied in but not written */
  560                                 uio->uio_resid += cc;
  561                                 return (EIO);
  562                         }
  563                 }
  564                 while (cc > 0) {
  565                         if ((tp->t_rawq.c_cc + tp->t_canq.c_cc) >= TTYHOG - 2 &&
  566                            (tp->t_canq.c_cc > 0 || !(tp->t_lflag&ICANON))) {
  567                                 wakeup(TSA_HUP_OR_INPUT(tp));
  568                                 goto block;
  569                         }
  570                         ttyld_rint(tp, *cp++);
  571                         cnt++;
  572                         cc--;
  573                 }
  574                 cc = 0;
  575         }
  576         return (0);
  577 block:
  578         /*
  579          * Come here to wait for slave to open, for space
  580          * in outq, or space in rawq, or an empty canq.
  581          */
  582         if ((tp->t_state & TS_CONNECTED) == 0) {
  583                 /* adjust for data copied in but not written */
  584                 uio->uio_resid += cc;
  585                 return (EIO);
  586         }
  587         if (flag & O_NONBLOCK) {
  588                 /* adjust for data copied in but not written */
  589                 uio->uio_resid += cc;
  590                 if (cnt == 0)
  591                         return (EWOULDBLOCK);
  592                 return (0);
  593         }
  594         error = tsleep(TSA_PTC_WRITE(tp), TTOPRI | PCATCH, "ptcout", 0);
  595         if (error) {
  596                 /* adjust for data copied in but not written */
  597                 uio->uio_resid += cc;
  598                 return (error);
  599         }
  600         goto again;
  601 }
  602 
  603 /*ARGSUSED*/
  604 static  int
  605 ptcioctl(struct cdev *dev, u_long cmd, caddr_t data, int flag, struct thread *td)
  606 {
  607         struct tty *tp = dev->si_tty;
  608         struct ptsc *pt = dev->si_drv1;
  609 #if defined(COMPAT_FREEBSD6) || defined(COMPAT_FREEBSD5) || \
  610     defined(COMPAT_FREEBSD4) || defined(COMPAT_43)
  611         int ival;
  612 #endif
  613 
  614         switch (cmd) {
  615 
  616         case TIOCGPGRP:
  617                 /*
  618                  * We avoid calling ttioctl on the controller since,
  619                  * in that case, tp must be the controlling terminal.
  620                  */
  621                 *(int *)data = tp->t_pgrp ? tp->t_pgrp->pg_id : 0;
  622                 return (0);
  623 
  624         case TIOCPKT:
  625                 if (*(int *)data) {
  626                         if (pt->pt_flags & PF_UCNTL)
  627                                 return (EINVAL);
  628                         pt->pt_flags |= PF_PKT;
  629                 } else
  630                         pt->pt_flags &= ~PF_PKT;
  631                 return (0);
  632 
  633         case TIOCUCNTL:
  634                 if (*(int *)data) {
  635                         if (pt->pt_flags & PF_PKT)
  636                                 return (EINVAL);
  637                         pt->pt_flags |= PF_UCNTL;
  638                 } else
  639                         pt->pt_flags &= ~PF_UCNTL;
  640                 return (0);
  641         }
  642 
  643         /*
  644          * The rest of the ioctls shouldn't be called until
  645          * the slave is open.
  646          */
  647         if ((tp->t_state & TS_ISOPEN) == 0)
  648                 return (EAGAIN);
  649 
  650         switch (cmd) {
  651 #ifdef COMPAT_43TTY
  652         case TIOCSETP:
  653         case TIOCSETN:
  654 #endif
  655         case TIOCSETD:
  656         case TIOCSETA:
  657         case TIOCSETAW:
  658         case TIOCSETAF:
  659                 /*
  660                  * IF CONTROLLER STTY THEN MUST FLUSH TO PREVENT A HANG.
  661                  * ttywflush(tp) will hang if there are characters in
  662                  * the outq.
  663                  */
  664                 ndflush(&tp->t_outq, tp->t_outq.c_cc);
  665                 break;
  666 
  667 #if defined(COMPAT_FREEBSD6) || defined(COMPAT_FREEBSD5) || \
  668     defined(COMPAT_FREEBSD4) || defined(COMPAT_43)
  669         case _IO('t', 95):
  670                 ival = IOCPARM_IVAL(data);
  671                 data = (caddr_t)&ival;
  672                 /* FALLTHROUGH */
  673 #endif
  674         case TIOCSIG:
  675                 if (*(unsigned int *)data >= NSIG ||
  676                     *(unsigned int *)data == 0)
  677                         return(EINVAL);
  678                 if ((tp->t_lflag&NOFLSH) == 0)
  679                         ttyflush(tp, FREAD|FWRITE);
  680                 if (tp->t_pgrp != NULL) {
  681                         PGRP_LOCK(tp->t_pgrp);
  682                         pgsignal(tp->t_pgrp, *(unsigned int *)data, 1);
  683                         PGRP_UNLOCK(tp->t_pgrp);
  684                 }
  685                 if ((*(unsigned int *)data == SIGINFO) &&
  686                     ((tp->t_lflag&NOKERNINFO) == 0))
  687                         ttyinfo(tp);
  688                 return(0);
  689         }
  690 
  691         return (ptsioctl(dev, cmd, data, flag, td));
  692 }
  693 
  694 /*ARGSUSED*/
  695 static  int
  696 ptsioctl(struct cdev *dev, u_long cmd, caddr_t data, int flag, struct thread *td)
  697 {
  698         struct tty *tp = dev->si_tty;
  699         struct ptsc *pt = dev->si_drv1;
  700         u_char *cc = tp->t_cc;
  701         int stop, error;
  702 
  703         if (cmd == TIOCEXT) {
  704                 /*
  705                  * When the EXTPROC bit is being toggled, we need
  706                  * to send an TIOCPKT_IOCTL if the packet driver
  707                  * is turned on.
  708                  */
  709                 if (*(int *)data) {
  710                         if (pt->pt_flags & PF_PKT) {
  711                                 pt->pt_send |= TIOCPKT_IOCTL;
  712                                 ptcwakeup(tp, FREAD);
  713                         }
  714                         tp->t_lflag |= EXTPROC;
  715                 } else {
  716                         if ((tp->t_lflag & EXTPROC) &&
  717                             (pt->pt_flags & PF_PKT)) {
  718                                 pt->pt_send |= TIOCPKT_IOCTL;
  719                                 ptcwakeup(tp, FREAD);
  720                         }
  721                         tp->t_lflag &= ~EXTPROC;
  722                 }
  723                 return(0);
  724         }
  725         error = ttyioctl(dev, cmd, data, flag, td);
  726         if (error == ENOTTY) {
  727                 if (pt->pt_flags & PF_UCNTL &&
  728                     (cmd & ~0xff) == UIOCCMD(0)) {
  729                         if (cmd & 0xff) {
  730                                 pt->pt_ucntl = (u_char)cmd;
  731                                 ptcwakeup(tp, FREAD);
  732                         }
  733                         return (0);
  734                 }
  735                 error = ENOTTY;
  736         }
  737         /*
  738          * If external processing and packet mode send ioctl packet.
  739          */
  740         if ((tp->t_lflag&EXTPROC) && (pt->pt_flags & PF_PKT)) {
  741                 switch(cmd) {
  742                 case TIOCSETA:
  743                 case TIOCSETAW:
  744                 case TIOCSETAF:
  745 #ifdef COMPAT_43TTY
  746                 case TIOCSETP:
  747                 case TIOCSETN:
  748                 case TIOCSETC:
  749                 case TIOCSLTC:
  750                 case TIOCLBIS:
  751                 case TIOCLBIC:
  752                 case TIOCLSET:
  753 #endif
  754                         pt->pt_send |= TIOCPKT_IOCTL;
  755                         ptcwakeup(tp, FREAD);
  756                         break;
  757                 default:
  758                         break;
  759                 }
  760         }
  761         stop = (tp->t_iflag & IXON) && CCEQ(cc[VSTOP], CTRL('s'))
  762                 && CCEQ(cc[VSTART], CTRL('q'));
  763         if (pt->pt_flags & PF_NOSTOP) {
  764                 if (stop) {
  765                         pt->pt_send &= ~TIOCPKT_NOSTOP;
  766                         pt->pt_send |= TIOCPKT_DOSTOP;
  767                         pt->pt_flags &= ~PF_NOSTOP;
  768                         ptcwakeup(tp, FREAD);
  769                 }
  770         } else {
  771                 if (!stop) {
  772                         pt->pt_send &= ~TIOCPKT_DOSTOP;
  773                         pt->pt_send |= TIOCPKT_NOSTOP;
  774                         pt->pt_flags |= PF_NOSTOP;
  775                         ptcwakeup(tp, FREAD);
  776                 }
  777         }
  778         return (error);
  779 }
  780 
  781 static void
  782 pty_clone(void *arg, struct ucred *cr, char *name, int namelen,
  783     struct cdev **dev)
  784 {
  785         char *cp;
  786         int u;
  787 
  788         if (*dev != NULL)
  789                 return;
  790         if (bcmp(name, "pty", 3) != 0)
  791                 return;
  792         if (name[5] != '\0' || name[3] == '\0')
  793                 return;
  794         cp = index(names, name[3]);
  795         if (cp == NULL)
  796                 return;
  797         u = (cp - names) * 32;
  798         if (name[4] >= '' && name[4] <= '9')
  799                 u += name[4] - '';
  800         else if (name[4] >= 'a' && name[4] <= 'v')
  801                 u += name[4] - 'a' + 10;
  802         else
  803                 return;
  804         *dev = make_dev_credf(MAKEDEV_REF, &ptc_cdevsw, unit2minor(u), cr,
  805             UID_ROOT, GID_WHEEL, 0666, "pty%c%r", names[u / 32], u % 32);
  806         (*dev)->si_flags |= SI_CHEAPCLONE;
  807         return;
  808 }
  809 
  810 static void
  811 ptc_drvinit(void *unused)
  812 {
  813 
  814         EVENTHANDLER_REGISTER(dev_clone, pty_clone, 0, 1000);
  815 }
  816 
  817 SYSINIT(ptcdev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE,ptc_drvinit,NULL);

Cache object: 59a842709b10aa7221262b5378e1a9c5


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