pty.c revision 132226
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: head/sys/kern/tty_pty.c 132226 2004-07-15 20:47:41Z phk $"); 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/lock.h> 44#include <sys/mutex.h> 45#include <sys/sx.h> 46#ifndef BURN_BRIDGES 47#if defined(COMPAT_43) 48#include <sys/ioctl_compat.h> 49#endif 50#endif 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/vnode.h> 58#include <sys/signalvar.h> 59#include <sys/malloc.h> 60 61static MALLOC_DEFINE(M_PTY, "ptys", "pty data structures"); 62 63static void ptsstart(struct tty *tp); 64static void ptsstop(struct tty *tp, int rw); 65static void ptcwakeup(struct tty *tp, int flag); 66static struct cdev *ptyinit(struct cdev *cdev); 67 68static d_open_t ptsopen; 69static d_close_t ptsclose; 70static d_read_t ptsread; 71static d_write_t ptswrite; 72static d_ioctl_t ptyioctl; 73static d_open_t ptcopen; 74static d_close_t ptcclose; 75static d_read_t ptcread; 76static d_write_t ptcwrite; 77static d_poll_t ptcpoll; 78 79#define CDEV_MAJOR_S 5 80static 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 = ptyioctl, 87 .d_name = "pts", 88 .d_maj = CDEV_MAJOR_S, 89 .d_flags = D_TTY | D_NEEDGIANT, 90}; 91 92#define CDEV_MAJOR_C 6 93static struct cdevsw ptc_cdevsw = { 94 .d_version = D_VERSION, 95 .d_open = ptcopen, 96 .d_close = ptcclose, 97 .d_read = ptcread, 98 .d_write = ptcwrite, 99 .d_ioctl = ptyioctl, 100 .d_poll = ptcpoll, 101 .d_name = "ptc", 102 .d_maj = CDEV_MAJOR_C, 103 .d_flags = D_TTY | D_NEEDGIANT, 104}; 105 106#define BUFSIZ 100 /* Chunk size iomoved to/from user */ 107 108struct 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 struct prison *pt_prison; 116}; 117 118#define PF_PKT 0x08 /* packet mode */ 119#define PF_STOPPED 0x10 /* user told stopped */ 120#define PF_NOSTOP 0x40 121#define PF_UCNTL 0x80 /* user control mode */ 122 123#define TSA_PTC_READ(tp) ((void *)&(tp)->t_outq.c_cf) 124#define TSA_PTC_WRITE(tp) ((void *)&(tp)->t_rawq.c_cl) 125#define TSA_PTS_READ(tp) ((void *)&(tp)->t_canq) 126 127static char *names = "pqrsPQRS"; 128/* 129 * This function creates and initializes a pts/ptc pair 130 * 131 * pts == /dev/tty[pqrsPQRS][0123456789abcdefghijklmnopqrstuv] 132 * ptc == /dev/pty[pqrsPQRS][0123456789abcdefghijklmnopqrstuv] 133 * 134 * XXX: define and add mapping of upper minor bits to allow more 135 * than 256 ptys. 136 */ 137static struct cdev * 138ptyinit(struct cdev *devc) 139{ 140 struct cdev *devs; 141 struct ptsc *pt; 142 int n; 143 144 n = minor(devc); 145 /* For now we only map the lower 8 bits of the minor */ 146 if (n & ~0xff) 147 return (NULL); 148 149 devc->si_flags &= ~SI_CHEAPCLONE; 150 151 pt = malloc(sizeof(*pt), M_PTY, M_WAITOK | M_ZERO); 152 pt->devs = devs = make_dev(&pts_cdevsw, n, 153 UID_ROOT, GID_WHEEL, 0666, "tty%c%r", names[n / 32], n % 32); 154 pt->devc = devc; 155 156 pt->pt_tty = ttymalloc(pt->pt_tty); 157 devs->si_drv1 = devc->si_drv1 = pt; 158 devs->si_tty = devc->si_tty = pt->pt_tty; 159 pt->pt_tty->t_dev = devs; 160 return (devc); 161} 162 163/*ARGSUSED*/ 164static int 165ptsopen(struct cdev *dev, int flag, int devtype, struct thread *td) 166{ 167 struct tty *tp; 168 int error; 169 struct ptsc *pt; 170 171 if (!dev->si_drv1) 172 return(ENXIO); 173 pt = dev->si_drv1; 174 tp = dev->si_tty; 175 if ((tp->t_state & TS_ISOPEN) == 0) { 176 ttychars(tp); /* Set up default chars */ 177 tp->t_iflag = TTYDEF_IFLAG; 178 tp->t_oflag = TTYDEF_OFLAG; 179 tp->t_lflag = TTYDEF_LFLAG; 180 tp->t_cflag = TTYDEF_CFLAG; 181 tp->t_ispeed = tp->t_ospeed = TTYDEF_SPEED; 182 } else if (tp->t_state & TS_XCLUDE && suser(td)) 183 return (EBUSY); 184 else if (pt->pt_prison != td->td_ucred->cr_prison) 185 return (EBUSY); 186 if (tp->t_oproc) /* Ctrlr still around. */ 187 (void)ttyld_modem(tp, 1); 188 while ((tp->t_state & TS_CARR_ON) == 0) { 189 if (flag&FNONBLOCK) 190 break; 191 error = ttysleep(tp, TSA_CARR_ON(tp), TTIPRI | PCATCH, 192 "ptsopn", 0); 193 if (error) 194 return (error); 195 } 196 error = ttyld_open(tp, dev); 197 if (error == 0) 198 ptcwakeup(tp, FREAD|FWRITE); 199 return (error); 200} 201 202static int 203ptsclose(struct cdev *dev, int flag, int mode, struct thread *td) 204{ 205 struct tty *tp; 206 int err; 207 208 tp = dev->si_tty; 209 err = ttyld_close(tp, flag); 210 (void) tty_close(tp); 211 return (err); 212} 213 214static int 215ptsread(struct cdev *dev, struct uio *uio, int flag) 216{ 217 struct tty *tp = dev->si_tty; 218 int error = 0; 219 220 if (tp->t_oproc) 221 error = ttyld_read(tp, uio, flag); 222 ptcwakeup(tp, FWRITE); 223 return (error); 224} 225 226/* 227 * Write to pseudo-tty. 228 * Wakeups of controlling tty will happen 229 * indirectly, when tty driver calls ptsstart. 230 */ 231static int 232ptswrite(struct cdev *dev, struct uio *uio, int flag) 233{ 234 struct tty *tp; 235 236 tp = dev->si_tty; 237 if (tp->t_oproc == 0) 238 return (EIO); 239 return (ttyld_write(tp, uio, flag)); 240} 241 242/* 243 * Start output on pseudo-tty. 244 * Wake up process selecting or sleeping for input from controlling tty. 245 */ 246static void 247ptsstart(struct tty *tp) 248{ 249 struct ptsc *pt = tp->t_dev->si_drv1; 250 251 if (tp->t_state & TS_TTSTOP) 252 return; 253 if (pt->pt_flags & PF_STOPPED) { 254 pt->pt_flags &= ~PF_STOPPED; 255 pt->pt_send = TIOCPKT_START; 256 } 257 ptcwakeup(tp, FREAD); 258} 259 260static void 261ptcwakeup(struct tty *tp, int flag) 262{ 263 struct ptsc *pt = tp->t_dev->si_drv1; 264 265 if (flag & FREAD) { 266 selwakeuppri(&pt->pt_selr, TTIPRI); 267 wakeup(TSA_PTC_READ(tp)); 268 } 269 if (flag & FWRITE) { 270 selwakeuppri(&pt->pt_selw, TTOPRI); 271 wakeup(TSA_PTC_WRITE(tp)); 272 } 273} 274 275static int 276ptcopen(struct cdev *dev, int flag, int devtype, struct thread *td) 277{ 278 struct tty *tp; 279 struct ptsc *pt; 280 281 if (!dev->si_drv1) 282 ptyinit(dev); 283 if (!dev->si_drv1) 284 return(ENXIO); 285 tp = dev->si_tty; 286 if (tp->t_oproc) 287 return (EIO); 288 tp->t_timeout = -1; 289 tp->t_oproc = ptsstart; 290 tp->t_stop = ptsstop; 291 (void)ttyld_modem(tp, 1); 292 tp->t_lflag &= ~EXTPROC; 293 pt = dev->si_drv1; 294 pt->pt_prison = td->td_ucred->cr_prison; 295 pt->pt_flags = 0; 296 pt->pt_send = 0; 297 pt->pt_ucntl = 0; 298 return (0); 299} 300 301static int 302ptcclose(struct cdev *dev, int flags, int fmt, struct thread *td) 303{ 304 struct tty *tp; 305 306 tp = dev->si_tty; 307 (void)ttyld_modem(tp, 0); 308 309 /* 310 * XXX MDMBUF makes no sense for ptys but would inhibit the above 311 * l_modem(). CLOCAL makes sense but isn't supported. Special 312 * l_modem()s that ignore carrier drop make no sense for ptys but 313 * may be in use because other parts of the line discipline make 314 * sense for ptys. Recover by doing everything that a normal 315 * ttymodem() would have done except for sending a SIGHUP. 316 */ 317 if (tp->t_state & TS_ISOPEN) { 318 tp->t_state &= ~(TS_CARR_ON | TS_CONNECTED); 319 tp->t_state |= TS_ZOMBIE; 320 ttyflush(tp, FREAD | FWRITE); 321 } 322 323 tp->t_oproc = 0; /* mark closed */ 324 return (0); 325} 326 327static int 328ptcread(struct cdev *dev, struct uio *uio, int flag) 329{ 330 struct tty *tp = dev->si_tty; 331 struct ptsc *pt = dev->si_drv1; 332 char buf[BUFSIZ]; 333 int error = 0, cc; 334 335 /* 336 * We want to block until the slave 337 * is open, and there's something to read; 338 * but if we lost the slave or we're NBIO, 339 * then return the appropriate error instead. 340 */ 341 for (;;) { 342 if (tp->t_state&TS_ISOPEN) { 343 if (pt->pt_flags&PF_PKT && pt->pt_send) { 344 error = ureadc((int)pt->pt_send, uio); 345 if (error) 346 return (error); 347 if (pt->pt_send & TIOCPKT_IOCTL) { 348 cc = min(uio->uio_resid, 349 sizeof(tp->t_termios)); 350 uiomove(&tp->t_termios, cc, uio); 351 } 352 pt->pt_send = 0; 353 return (0); 354 } 355 if (pt->pt_flags&PF_UCNTL && pt->pt_ucntl) { 356 error = ureadc((int)pt->pt_ucntl, uio); 357 if (error) 358 return (error); 359 pt->pt_ucntl = 0; 360 return (0); 361 } 362 if (tp->t_outq.c_cc && (tp->t_state&TS_TTSTOP) == 0) 363 break; 364 } 365 if ((tp->t_state & TS_CONNECTED) == 0) 366 return (0); /* EOF */ 367 if (flag & IO_NDELAY) 368 return (EWOULDBLOCK); 369 error = tsleep(TSA_PTC_READ(tp), TTIPRI | PCATCH, "ptcin", 0); 370 if (error) 371 return (error); 372 } 373 if (pt->pt_flags & (PF_PKT|PF_UCNTL)) 374 error = ureadc(0, uio); 375 while (uio->uio_resid > 0 && error == 0) { 376 cc = q_to_b(&tp->t_outq, buf, min(uio->uio_resid, BUFSIZ)); 377 if (cc <= 0) 378 break; 379 error = uiomove(buf, cc, uio); 380 } 381 ttwwakeup(tp); 382 return (error); 383} 384 385static void 386ptsstop(struct tty *tp, int flush) 387{ 388 struct ptsc *pt = tp->t_dev->si_drv1; 389 int flag; 390 391 /* note: FLUSHREAD and FLUSHWRITE already ok */ 392 if (flush == 0) { 393 flush = TIOCPKT_STOP; 394 pt->pt_flags |= PF_STOPPED; 395 } else 396 pt->pt_flags &= ~PF_STOPPED; 397 pt->pt_send |= flush; 398 /* change of perspective */ 399 flag = 0; 400 if (flush & FREAD) 401 flag |= FWRITE; 402 if (flush & FWRITE) 403 flag |= FREAD; 404 ptcwakeup(tp, flag); 405} 406 407static int 408ptcpoll(struct cdev *dev, int events, struct thread *td) 409{ 410 struct tty *tp = dev->si_tty; 411 struct ptsc *pt = dev->si_drv1; 412 int revents = 0; 413 int s; 414 415 if ((tp->t_state & TS_CONNECTED) == 0) 416 return (events & 417 (POLLHUP | POLLIN | POLLRDNORM | POLLOUT | POLLWRNORM)); 418 419 /* 420 * Need to block timeouts (ttrstart). 421 */ 422 s = spltty(); 423 424 if (events & (POLLIN | POLLRDNORM)) 425 if ((tp->t_state & TS_ISOPEN) && 426 ((tp->t_outq.c_cc && (tp->t_state & TS_TTSTOP) == 0) || 427 ((pt->pt_flags & PF_PKT) && pt->pt_send) || 428 ((pt->pt_flags & PF_UCNTL) && pt->pt_ucntl))) 429 revents |= events & (POLLIN | POLLRDNORM); 430 431 if (events & (POLLOUT | POLLWRNORM)) 432 if (tp->t_state & TS_ISOPEN && 433 (((tp->t_rawq.c_cc + tp->t_canq.c_cc < TTYHOG - 2) || 434 (tp->t_canq.c_cc == 0 && (tp->t_lflag & ICANON))))) 435 revents |= events & (POLLOUT | POLLWRNORM); 436 437 if (events & POLLHUP) 438 if ((tp->t_state & TS_CARR_ON) == 0) 439 revents |= POLLHUP; 440 441 if (revents == 0) { 442 if (events & (POLLIN | POLLRDNORM)) 443 selrecord(td, &pt->pt_selr); 444 445 if (events & (POLLOUT | POLLWRNORM)) 446 selrecord(td, &pt->pt_selw); 447 } 448 splx(s); 449 450 return (revents); 451} 452 453static int 454ptcwrite(struct cdev *dev, struct uio *uio, int flag) 455{ 456 struct tty *tp = dev->si_tty; 457 u_char *cp = 0; 458 int cc = 0; 459 u_char locbuf[BUFSIZ]; 460 int cnt = 0; 461 int error = 0; 462 463again: 464 if ((tp->t_state&TS_ISOPEN) == 0) 465 goto block; 466 while (uio->uio_resid > 0 || cc > 0) { 467 if (cc == 0) { 468 cc = min(uio->uio_resid, BUFSIZ); 469 cp = locbuf; 470 error = uiomove(cp, cc, uio); 471 if (error) 472 return (error); 473 /* check again for safety */ 474 if ((tp->t_state & TS_ISOPEN) == 0) { 475 /* adjust for data copied in but not written */ 476 uio->uio_resid += cc; 477 return (EIO); 478 } 479 } 480 while (cc > 0) { 481 if ((tp->t_rawq.c_cc + tp->t_canq.c_cc) >= TTYHOG - 2 && 482 (tp->t_canq.c_cc > 0 || !(tp->t_lflag&ICANON))) { 483 wakeup(TSA_HUP_OR_INPUT(tp)); 484 goto block; 485 } 486 ttyld_rint(tp, *cp++); 487 cnt++; 488 cc--; 489 } 490 cc = 0; 491 } 492 return (0); 493block: 494 /* 495 * Come here to wait for slave to open, for space 496 * in outq, or space in rawq, or an empty canq. 497 */ 498 if ((tp->t_state & TS_CONNECTED) == 0) { 499 /* adjust for data copied in but not written */ 500 uio->uio_resid += cc; 501 return (EIO); 502 } 503 if (flag & IO_NDELAY) { 504 /* adjust for data copied in but not written */ 505 uio->uio_resid += cc; 506 if (cnt == 0) 507 return (EWOULDBLOCK); 508 return (0); 509 } 510 error = tsleep(TSA_PTC_WRITE(tp), TTOPRI | PCATCH, "ptcout", 0); 511 if (error) { 512 /* adjust for data copied in but not written */ 513 uio->uio_resid += cc; 514 return (error); 515 } 516 goto again; 517} 518 519/*ARGSUSED*/ 520static int 521ptyioctl(struct cdev *dev, u_long cmd, caddr_t data, int flag, struct thread *td) 522{ 523 struct tty *tp = dev->si_tty; 524 struct ptsc *pt = dev->si_drv1; 525 u_char *cc = tp->t_cc; 526 int stop, error; 527 528 if (devsw(dev)->d_open == ptcopen) { 529 switch (cmd) { 530 531 case TIOCGPGRP: 532 /* 533 * We avoid calling ttioctl on the controller since, 534 * in that case, tp must be the controlling terminal. 535 */ 536 *(int *)data = tp->t_pgrp ? tp->t_pgrp->pg_id : 0; 537 return (0); 538 539 case TIOCPKT: 540 if (*(int *)data) { 541 if (pt->pt_flags & PF_UCNTL) 542 return (EINVAL); 543 pt->pt_flags |= PF_PKT; 544 } else 545 pt->pt_flags &= ~PF_PKT; 546 return (0); 547 548 case TIOCUCNTL: 549 if (*(int *)data) { 550 if (pt->pt_flags & PF_PKT) 551 return (EINVAL); 552 pt->pt_flags |= PF_UCNTL; 553 } else 554 pt->pt_flags &= ~PF_UCNTL; 555 return (0); 556 } 557 558 /* 559 * The rest of the ioctls shouldn't be called until 560 * the slave is open. 561 */ 562 if ((tp->t_state & TS_ISOPEN) == 0) 563 return (EAGAIN); 564 565 switch (cmd) { 566#ifndef BURN_BRIDGES 567#ifdef COMPAT_43 568 case TIOCSETP: 569 case TIOCSETN: 570#endif 571#endif 572 case TIOCSETD: 573 case TIOCSETA: 574 case TIOCSETAW: 575 case TIOCSETAF: 576 /* 577 * IF CONTROLLER STTY THEN MUST FLUSH TO PREVENT A HANG. 578 * ttywflush(tp) will hang if there are characters in 579 * the outq. 580 */ 581 ndflush(&tp->t_outq, tp->t_outq.c_cc); 582 break; 583 584 case TIOCSIG: 585 if (*(unsigned int *)data >= NSIG || 586 *(unsigned int *)data == 0) 587 return(EINVAL); 588 if ((tp->t_lflag&NOFLSH) == 0) 589 ttyflush(tp, FREAD|FWRITE); 590 if (tp->t_pgrp != NULL) { 591 PGRP_LOCK(tp->t_pgrp); 592 pgsignal(tp->t_pgrp, *(unsigned int *)data, 1); 593 PGRP_UNLOCK(tp->t_pgrp); 594 } 595 if ((*(unsigned int *)data == SIGINFO) && 596 ((tp->t_lflag&NOKERNINFO) == 0)) 597 ttyinfo(tp); 598 return(0); 599 } 600 } 601 if (cmd == TIOCEXT) { 602 /* 603 * When the EXTPROC bit is being toggled, we need 604 * to send an TIOCPKT_IOCTL if the packet driver 605 * is turned on. 606 */ 607 if (*(int *)data) { 608 if (pt->pt_flags & PF_PKT) { 609 pt->pt_send |= TIOCPKT_IOCTL; 610 ptcwakeup(tp, FREAD); 611 } 612 tp->t_lflag |= EXTPROC; 613 } else { 614 if ((tp->t_lflag & EXTPROC) && 615 (pt->pt_flags & PF_PKT)) { 616 pt->pt_send |= TIOCPKT_IOCTL; 617 ptcwakeup(tp, FREAD); 618 } 619 tp->t_lflag &= ~EXTPROC; 620 } 621 return(0); 622 } 623 error = ttyioctl(dev, cmd, data, flag, td); 624 if (error == ENOTTY) { 625 if (pt->pt_flags & PF_UCNTL && 626 (cmd & ~0xff) == UIOCCMD(0)) { 627 if (cmd & 0xff) { 628 pt->pt_ucntl = (u_char)cmd; 629 ptcwakeup(tp, FREAD); 630 } 631 return (0); 632 } 633 error = ENOTTY; 634 } 635 /* 636 * If external processing and packet mode send ioctl packet. 637 */ 638 if ((tp->t_lflag&EXTPROC) && (pt->pt_flags & PF_PKT)) { 639 switch(cmd) { 640 case TIOCSETA: 641 case TIOCSETAW: 642 case TIOCSETAF: 643#ifndef BURN_BRIDGES 644#ifdef COMPAT_43 645 case TIOCSETP: 646 case TIOCSETN: 647 case TIOCSETC: 648 case TIOCSLTC: 649 case TIOCLBIS: 650 case TIOCLBIC: 651 case TIOCLSET: 652#endif 653#endif 654 pt->pt_send |= TIOCPKT_IOCTL; 655 ptcwakeup(tp, FREAD); 656 break; 657 default: 658 break; 659 } 660 } 661 stop = (tp->t_iflag & IXON) && CCEQ(cc[VSTOP], CTRL('s')) 662 && CCEQ(cc[VSTART], CTRL('q')); 663 if (pt->pt_flags & PF_NOSTOP) { 664 if (stop) { 665 pt->pt_send &= ~TIOCPKT_NOSTOP; 666 pt->pt_send |= TIOCPKT_DOSTOP; 667 pt->pt_flags &= ~PF_NOSTOP; 668 ptcwakeup(tp, FREAD); 669 } 670 } else { 671 if (!stop) { 672 pt->pt_send &= ~TIOCPKT_DOSTOP; 673 pt->pt_send |= TIOCPKT_NOSTOP; 674 pt->pt_flags |= PF_NOSTOP; 675 ptcwakeup(tp, FREAD); 676 } 677 } 678 return (error); 679} 680 681static void 682pty_clone(void *arg, char *name, int namelen, struct cdev **dev) 683{ 684 int u; 685 686 if (*dev != NULL) 687 return; 688 if (bcmp(name, "pty", 3) != 0) 689 return; 690 if (name[5] != '\0') 691 return; 692 switch (name[3]) { 693 case 'p': u = 0; break; 694 case 'q': u = 32; break; 695 case 'r': u = 64; break; 696 case 's': u = 96; break; 697 case 'P': u = 128; break; 698 case 'Q': u = 160; break; 699 case 'R': u = 192; break; 700 case 'S': u = 224; break; 701 default: return; 702 } 703 if (name[4] >= '0' && name[4] <= '9') 704 u += name[4] - '0'; 705 else if (name[4] >= 'a' && name[4] <= 'v') 706 u += name[4] - 'a' + 10; 707 else 708 return; 709 *dev = make_dev(&ptc_cdevsw, u, 710 UID_ROOT, GID_WHEEL, 0666, "pty%c%r", names[u / 32], u % 32); 711 (*dev)->si_flags |= SI_CHEAPCLONE; 712 return; 713} 714 715static void 716ptc_drvinit(void *unused) 717{ 718 719 EVENTHANDLER_REGISTER(dev_clone, pty_clone, 0, 1000); 720} 721 722SYSINIT(ptcdev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR_C,ptc_drvinit,NULL) 723