1 /* $NetBSD: tty_pty.c,v 1.149 2021/10/11 01:07:36 thorpej Exp $ */ 2 3 /* 4 * Copyright (c) 1982, 1986, 1989, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * @(#)tty_pty.c 8.4 (Berkeley) 2/20/95 32 */ 33 34 /* 35 * Pseudo-teletype Driver 36 * (Actually two drivers, requiring two entries in 'cdevsw') 37 */ 38 39 #include <sys/cdefs.h> 40 __KERNEL_RCSID(0, "$NetBSD: tty_pty.c,v 1.149 2021/10/11 01:07:36 thorpej Exp $"); 41 42 #include "opt_ptm.h" 43 44 #define TTY_ALLOW_PRIVATE 45 46 #include <sys/param.h> 47 #include <sys/systm.h> 48 #include <sys/ioctl.h> 49 #include <sys/ioctl_compat.h> 50 #include <sys/proc.h> 51 #include <sys/tty.h> 52 #include <sys/stat.h> 53 #include <sys/file.h> 54 #include <sys/kernel.h> 55 #include <sys/vnode.h> 56 #include <sys/namei.h> 57 #include <sys/signalvar.h> 58 #include <sys/uio.h> 59 #include <sys/filedesc.h> 60 #include <sys/conf.h> 61 #include <sys/poll.h> 62 #include <sys/pty.h> 63 #include <sys/kauth.h> 64 65 #include "ioconf.h" 66 67 #define DEFAULT_NPTYS 16 /* default number of initial ptys */ 68 #define DEFAULT_MAXPTYS 992 /* default maximum number of ptys */ 69 70 #define BUFSIZ 100 /* Chunk size iomoved to/from user */ 71 72 struct pt_softc { 73 struct tty *pt_tty; 74 int pt_flags; 75 struct selinfo pt_selr, pt_selw; 76 u_char pt_send; 77 u_char pt_ucntl; 78 }; 79 80 static struct pt_softc **pt_softc = NULL; /* pty array */ 81 static int maxptys = DEFAULT_MAXPTYS; /* maximum number of ptys (sysctable) */ 82 kmutex_t pt_softc_mutex; 83 int npty = 0; /* for pstat -t */ 84 85 #define PF_PKT 0x08 /* packet mode */ 86 #define PF_STOPPED 0x10 /* user told stopped */ 87 #define PF_REMOTE 0x20 /* remote and flow controlled input */ 88 #define PF_NOSTOP 0x40 89 #define PF_UCNTL 0x80 /* user control mode */ 90 91 void ptcwakeup(struct tty *, int); 92 void ptsstart(struct tty *); 93 int pty_maxptys(int, int); 94 95 static struct pt_softc **ptyarralloc(int); 96 97 dev_type_open(ptcopen); 98 dev_type_close(ptcclose); 99 dev_type_read(ptcread); 100 dev_type_write(ptcwrite); 101 dev_type_poll(ptcpoll); 102 dev_type_kqfilter(ptckqfilter); 103 104 dev_type_open(ptsopen); 105 dev_type_close(ptsclose); 106 dev_type_read(ptsread); 107 dev_type_write(ptswrite); 108 dev_type_stop(ptsstop); 109 dev_type_poll(ptspoll); 110 111 dev_type_ioctl(ptyioctl); 112 dev_type_tty(ptytty); 113 114 const struct cdevsw ptc_cdevsw = { 115 .d_open = ptcopen, 116 .d_close = ptcclose, 117 .d_read = ptcread, 118 .d_write = ptcwrite, 119 .d_ioctl = ptyioctl, 120 .d_stop = nullstop, 121 .d_tty = ptytty, 122 .d_poll = ptcpoll, 123 .d_mmap = nommap, 124 .d_kqfilter = ptckqfilter, 125 .d_discard = nodiscard, 126 .d_flag = D_TTY 127 }; 128 129 const struct cdevsw pts_cdevsw = { 130 .d_open = ptsopen, 131 .d_close = ptsclose, 132 .d_read = ptsread, 133 .d_write = ptswrite, 134 .d_ioctl = ptyioctl, 135 .d_stop = ptsstop, 136 .d_tty = ptytty, 137 .d_poll = ptspoll, 138 .d_mmap = nommap, 139 .d_kqfilter = ttykqfilter, 140 .d_discard = nodiscard, 141 .d_flag = D_TTY 142 }; 143 144 #if defined(pmax) 145 /* 146 * Used by arch/pmax/conf/majors.pmax, which needs a second copy as it 147 * needs to map this stuff to two pairs of majors. 148 */ 149 150 const struct cdevsw ptc_ultrix_cdevsw = { 151 .d_open = ptcopen, 152 .d_close = ptcclose, 153 .d_read = ptcread, 154 .d_write = ptcwrite, 155 .d_ioctl = ptyioctl, 156 .d_stop = nullstop, 157 .d_tty = ptytty, 158 .d_poll = ptcpoll, 159 .d_mmap = nommap, 160 .d_kqfilter = ptckqfilter, 161 .d_discard = nodiscard, 162 .d_flag = D_TTY 163 }; 164 165 const struct cdevsw pts_ultrix_cdevsw = { 166 .d_open = ptsopen, 167 .d_close = ptsclose, 168 .d_read = ptsread, 169 .d_write = ptswrite, 170 .d_ioctl = ptyioctl, 171 .d_stop = ptsstop, 172 .d_tty = ptytty, 173 .d_poll = ptspoll, 174 .d_mmap = nommap, 175 .d_kqfilter = ttykqfilter, 176 .d_discard = nodiscard, 177 .d_flag = D_TTY 178 }; 179 #endif /* defined(pmax) */ 180 181 /* 182 * Check if a pty is free to use. 183 */ 184 int 185 pty_isfree(int minor, int lock) 186 { 187 struct pt_softc *pt = pt_softc[minor]; 188 if (lock) 189 mutex_enter(&pt_softc_mutex); 190 minor = pt == NULL || pt->pt_tty == NULL || 191 pt->pt_tty->t_oproc == NULL; 192 if (lock) 193 mutex_exit(&pt_softc_mutex); 194 return minor; 195 } 196 197 /* 198 * Allocate and zero array of nelem elements. 199 */ 200 static struct pt_softc ** 201 ptyarralloc(int nelem) 202 { 203 struct pt_softc **pt; 204 nelem += 10; 205 pt = kmem_zalloc(nelem * sizeof(*pt), KM_SLEEP); 206 return pt; 207 } 208 209 static void 210 ptyarrfree(struct pt_softc **pt, int nelem) 211 { 212 213 nelem += 10; 214 kmem_free(pt, nelem * sizeof(*pt)); 215 } 216 217 /* 218 * Check if the minor is correct and ensure necessary structures 219 * are properly allocated. 220 */ 221 int 222 pty_check(int ptn) 223 { 224 struct pt_softc *pti; 225 226 if (ptn >= npty) { 227 struct pt_softc **newpt, **oldpt; 228 int newnpty; 229 int oldnpty; 230 231 /* check if the requested pty can be granted */ 232 if (ptn >= maxptys) { 233 limit_reached: 234 tablefull("pty", "increase kern.maxptys"); 235 return ENXIO; 236 } 237 238 /* Allocate a larger pty array */ 239 for (newnpty = npty; newnpty <= ptn;) 240 newnpty *= 2; 241 if (newnpty > maxptys) 242 newnpty = maxptys; 243 newpt = ptyarralloc(newnpty); 244 245 /* 246 * Now grab the pty array mutex - we need to ensure 247 * that the pty array is consistent while copying its 248 * content to newly allocated, larger space; we also 249 * need to be safe against pty_maxptys(). 250 */ 251 mutex_enter(&pt_softc_mutex); 252 253 if (newnpty >= maxptys) { 254 /* limit cut away beneath us... */ 255 if (ptn >= maxptys) { 256 mutex_exit(&pt_softc_mutex); 257 ptyarrfree(newpt, newnpty); 258 goto limit_reached; 259 } 260 newnpty = maxptys; 261 } 262 263 /* 264 * If the pty array was not enlarged while we were waiting 265 * for mutex, copy current contents of pt_softc[] to newly 266 * allocated array and start using the new bigger array. 267 */ 268 if (newnpty > npty) { 269 memcpy(newpt, pt_softc, npty*sizeof(struct pt_softc *)); 270 oldpt = pt_softc; 271 oldnpty = npty; 272 pt_softc = newpt; 273 npty = newnpty; 274 } else { 275 /* was enlarged when waited for lock, free new space */ 276 oldpt = newpt; 277 oldnpty = newnpty; 278 } 279 280 mutex_exit(&pt_softc_mutex); 281 ptyarrfree(oldpt, oldnpty); 282 } 283 284 /* 285 * If the entry is not yet allocated, allocate one. The mutex is 286 * needed so that the state of pt_softc[] array is consistant 287 * in case it has been lengthened above. 288 */ 289 if (!pt_softc[ptn]) { 290 pti = kmem_zalloc(sizeof(*pti), KM_SLEEP); 291 292 selinit(&pti->pt_selr); 293 selinit(&pti->pt_selw); 294 pti->pt_tty = tty_alloc(); 295 296 mutex_enter(&pt_softc_mutex); 297 298 /* 299 * Check the entry again - it might have been 300 * added while we were waiting for mutex. 301 */ 302 if (pt_softc[ptn]) { 303 mutex_exit(&pt_softc_mutex); 304 tty_free(pti->pt_tty); 305 seldestroy(&pti->pt_selr); 306 seldestroy(&pti->pt_selw); 307 kmem_free(pti, sizeof(*pti)); 308 return 0; 309 } 310 tty_attach(pti->pt_tty); 311 pt_softc[ptn] = pti; 312 313 mutex_exit(&pt_softc_mutex); 314 } 315 316 return 0; 317 } 318 319 /* 320 * Set maxpty in thread-safe way. Returns 0 in case of error, otherwise 321 * new value of maxptys. 322 */ 323 int 324 pty_maxptys(int newmax, int set) 325 { 326 if (!set) 327 return maxptys; 328 329 /* 330 * We have to grab the pt_softc lock, so that we would pick correct 331 * value of npty (might be modified in pty_check()). 332 */ 333 mutex_enter(&pt_softc_mutex); 334 335 /* 336 * The value cannot be set to value lower than the highest pty 337 * number ever allocated. 338 */ 339 if (newmax >= npty) 340 maxptys = newmax; 341 else 342 newmax = 0; 343 344 mutex_exit(&pt_softc_mutex); 345 346 return newmax; 347 } 348 349 /* 350 * Establish n (or default if n is 1) ptys in the system. 351 */ 352 void 353 ptyattach(int n) 354 { 355 356 mutex_init(&pt_softc_mutex, MUTEX_DEFAULT, IPL_NONE); 357 358 /* maybe should allow 0 => none? */ 359 if (n <= 1) 360 n = DEFAULT_NPTYS; 361 pt_softc = ptyarralloc(n); 362 npty = n; 363 #ifndef NO_DEV_PTM 364 ptmattach(1); 365 #endif 366 } 367 368 /*ARGSUSED*/ 369 int 370 ptsopen(dev_t dev, int flag, int devtype, struct lwp *l) 371 { 372 struct pt_softc *pti; 373 struct tty *tp; 374 int error; 375 int ptn = minor(dev); 376 377 if ((error = pty_check(ptn)) != 0) 378 return error; 379 380 mutex_spin_enter(&tty_lock); 381 pti = pt_softc[ptn]; 382 tp = pti->pt_tty; 383 if (!ISSET(tp->t_state, TS_ISOPEN)) { 384 tp->t_dev = dev; 385 ttychars(tp); /* Set up default chars */ 386 tp->t_iflag = TTYDEF_IFLAG; 387 tp->t_oflag = TTYDEF_OFLAG; 388 tp->t_lflag = TTYDEF_LFLAG; 389 tp->t_cflag = TTYDEF_CFLAG; 390 tp->t_ispeed = tp->t_ospeed = TTYDEF_SPEED; 391 ttsetwater(tp); /* would be done in xxparam() */ 392 } else if (kauth_authorize_device_tty(l->l_cred, KAUTH_DEVICE_TTY_OPEN, 393 tp) != 0) { 394 mutex_spin_exit(&tty_lock); 395 return EBUSY; 396 } 397 if (tp->t_oproc) /* Ctrlr still around. */ 398 SET(tp->t_state, TS_CARR_ON); 399 if (!ISSET(flag, O_NONBLOCK)) { 400 while (!ISSET(tp->t_state, TS_CARR_ON)) { 401 tp->t_wopen++; 402 error = ttysleep(tp, &tp->t_rawcv, true, 0); 403 tp->t_wopen--; 404 if (error != 0) { 405 mutex_spin_exit(&tty_lock); 406 return error; 407 } 408 } 409 } 410 mutex_spin_exit(&tty_lock); 411 error = (*tp->t_linesw->l_open)(dev, tp); 412 ptcwakeup(tp, FREAD|FWRITE); 413 return error; 414 } 415 416 int 417 ptsclose(dev_t dev, int flag, int mode, struct lwp *l) 418 { 419 struct pt_softc *pti = pt_softc[minor(dev)]; 420 struct tty *tp = pti->pt_tty; 421 int error; 422 423 error = (*tp->t_linesw->l_close)(tp, flag); 424 error |= ttyclose(tp); 425 ptcwakeup(tp, FREAD|FWRITE); 426 return error; 427 } 428 429 int 430 ptsread(dev_t dev, struct uio *uio, int flag) 431 { 432 struct proc *p = curproc; 433 struct pt_softc *pti = pt_softc[minor(dev)]; 434 struct tty *tp = pti->pt_tty; 435 int error = 0; 436 int cc, c; 437 438 again: 439 if (pti->pt_flags & PF_REMOTE) { 440 mutex_spin_enter(&tty_lock); 441 while (isbackground(p, tp)) { /* XXXSMP */ 442 if (sigismasked(curlwp, SIGTTIN) || 443 p->p_pgrp->pg_jobc == 0 || 444 p->p_lflag & PL_PPWAIT) { 445 mutex_spin_exit(&tty_lock); 446 return EIO; 447 } 448 ttysig(tp, TTYSIG_PG1, SIGTTIN); 449 error = ttypause(tp, hz); 450 if (error != 0) { 451 mutex_spin_exit(&tty_lock); 452 return error; 453 } 454 } 455 if (tp->t_canq.c_cc == 0) { 456 if (flag & IO_NDELAY) { 457 mutex_spin_exit(&tty_lock); 458 return EWOULDBLOCK; 459 } 460 error = ttysleep(tp, &tp->t_cancv, true, 0); 461 mutex_spin_exit(&tty_lock); 462 if (error != 0) 463 return error; 464 goto again; 465 } 466 while(error == 0 && tp->t_canq.c_cc > 1 && uio->uio_resid > 0) { 467 c = getc(&tp->t_canq); 468 mutex_spin_exit(&tty_lock); 469 error = ureadc(c, uio); 470 mutex_spin_enter(&tty_lock); 471 /* Re-check terminal state here? */ 472 } 473 if (tp->t_canq.c_cc == 1) 474 (void) getc(&tp->t_canq); 475 cc = tp->t_canq.c_cc; 476 mutex_spin_exit(&tty_lock); 477 if (cc) 478 return error; 479 } else if (tp->t_oproc) 480 error = (*tp->t_linesw->l_read)(tp, uio, flag); 481 ptcwakeup(tp, FWRITE); 482 return error; 483 } 484 485 /* 486 * Write to pseudo-tty. 487 * Wakeups of controlling tty will happen 488 * indirectly, when tty driver calls ptsstart. 489 */ 490 int 491 ptswrite(dev_t dev, struct uio *uio, int flag) 492 { 493 struct pt_softc *pti = pt_softc[minor(dev)]; 494 struct tty *tp = pti->pt_tty; 495 496 if (tp->t_oproc == NULL) 497 return EIO; 498 return (*tp->t_linesw->l_write)(tp, uio, flag); 499 } 500 501 /* 502 * Poll pseudo-tty. 503 */ 504 int 505 ptspoll(dev_t dev, int events, struct lwp *l) 506 { 507 struct pt_softc *pti = pt_softc[minor(dev)]; 508 struct tty *tp = pti->pt_tty; 509 510 if (tp->t_oproc == NULL) 511 return POLLHUP; 512 513 return (*tp->t_linesw->l_poll)(tp, events, l); 514 } 515 516 /* 517 * Start output on pseudo-tty. 518 * Wake up process polling or sleeping for input from controlling tty. 519 */ 520 void 521 ptsstart(struct tty *tp) 522 { 523 struct pt_softc *pti; 524 525 KASSERT(tp->t_dev != NODEV); 526 pti = pt_softc[minor(tp->t_dev)]; 527 528 KASSERT(mutex_owned(&tty_lock)); 529 530 if (ISSET(tp->t_state, TS_TTSTOP)) 531 return; 532 if (pti->pt_flags & PF_STOPPED) { 533 pti->pt_flags &= ~PF_STOPPED; 534 pti->pt_send = TIOCPKT_START; 535 } 536 537 selnotify(&pti->pt_selr, 0, NOTE_SUBMIT); 538 cv_broadcast(&tp->t_outcvf); 539 } 540 541 /* 542 * Stop output. 543 */ 544 void 545 ptsstop(struct tty *tp, int flush) 546 { 547 struct pt_softc *pti; 548 549 KASSERT(tp->t_dev != NODEV); 550 pti = pt_softc[minor(tp->t_dev)]; 551 552 KASSERT(mutex_owned(&tty_lock)); 553 554 /* note: FLUSHREAD and FLUSHWRITE already ok */ 555 CTASSERT(TIOCPKT_FLUSHREAD == FREAD); 556 CTASSERT(TIOCPKT_FLUSHWRITE == FWRITE); 557 if (flush == 0) { 558 flush = TIOCPKT_STOP; 559 pti->pt_flags |= PF_STOPPED; 560 } else 561 pti->pt_flags &= ~PF_STOPPED; 562 pti->pt_send |= flush; 563 564 /* change of perspective */ 565 if (flush & FREAD) { 566 selnotify(&pti->pt_selw, 0, NOTE_SUBMIT); 567 cv_broadcast(&tp->t_rawcvf); 568 } 569 if (flush & FWRITE) { 570 selnotify(&pti->pt_selr, 0, NOTE_SUBMIT); 571 cv_broadcast(&tp->t_outcvf); 572 } 573 } 574 575 void 576 ptcwakeup(struct tty *tp, int flag) 577 { 578 struct pt_softc *pti; 579 580 if (tp->t_dev == NODEV) 581 return; /* client side not open yet */ 582 583 pti = pt_softc[minor(tp->t_dev)]; 584 KASSERT(pti != NULL); 585 586 mutex_spin_enter(&tty_lock); 587 if (flag & FREAD) { 588 selnotify(&pti->pt_selr, 0, NOTE_SUBMIT); 589 cv_broadcast(&tp->t_outcvf); 590 } 591 if (flag & FWRITE) { 592 selnotify(&pti->pt_selw, 0, NOTE_SUBMIT); 593 cv_broadcast(&tp->t_rawcvf); 594 } 595 mutex_spin_exit(&tty_lock); 596 } 597 598 /*ARGSUSED*/ 599 int 600 ptcopen(dev_t dev, int flag, int devtype, struct lwp *l) 601 { 602 struct pt_softc *pti; 603 struct tty *tp; 604 int error; 605 int ptn = minor(dev); 606 607 if ((error = pty_check(ptn)) != 0) 608 return error; 609 610 pti = pt_softc[ptn]; 611 tp = pti->pt_tty; 612 613 mutex_spin_enter(&tty_lock); 614 if (tp->t_oproc) { 615 mutex_spin_exit(&tty_lock); 616 return EIO; 617 } 618 tp->t_dev = dev; 619 tp->t_oproc = ptsstart; 620 mutex_spin_exit(&tty_lock); 621 (void)(*tp->t_linesw->l_modem)(tp, 1); 622 CLR(tp->t_lflag, EXTPROC); 623 pti->pt_flags = 0; 624 pti->pt_send = 0; 625 pti->pt_ucntl = 0; 626 return 0; 627 } 628 629 /*ARGSUSED*/ 630 int 631 ptcclose(dev_t dev, int flag, int devtype, struct lwp *l) 632 { 633 struct pt_softc *pti = pt_softc[minor(dev)]; 634 struct tty *tp = pti->pt_tty; 635 636 (void)(*tp->t_linesw->l_modem)(tp, 0); 637 mutex_spin_enter(&tty_lock); 638 CLR(tp->t_state, TS_CARR_ON); 639 tp->t_oproc = NULL; /* mark closed */ 640 mutex_spin_exit(&tty_lock); 641 return 0; 642 } 643 644 int 645 ptcread(dev_t dev, struct uio *uio, int flag) 646 { 647 struct pt_softc *pti = pt_softc[minor(dev)]; 648 struct tty *tp = pti->pt_tty; 649 u_char bf[BUFSIZ]; 650 int error = 0, cc; 651 int c; 652 653 if (uio->uio_resid <= 0) 654 return EINVAL; 655 656 /* 657 * We want to block until the slave 658 * is open, and there's something to read; 659 * but if we lost the slave or we're NBIO, 660 * then return the appropriate error instead. 661 */ 662 mutex_spin_enter(&tty_lock); 663 for (;;) { 664 if (ISSET(tp->t_state, TS_ISOPEN)) { 665 if (pti->pt_flags & PF_PKT && (c = pti->pt_send)) { 666 pti->pt_send = 0; 667 mutex_spin_exit(&tty_lock); 668 error = ureadc(c, uio); 669 if (error != 0) 670 return error; 671 /* 672 * Since we don't have the tty locked, there's 673 * a risk of messing up `t_termios'. This is 674 * relevant only if the tty got closed and then 675 * opened again while we were out uiomoving. 676 */ 677 if (c & TIOCPKT_IOCTL) { 678 cc = uimin(uio->uio_resid, 679 sizeof(tp->t_termios)); 680 uiomove((void *) &tp->t_termios, 681 cc, uio); 682 } 683 return 0; 684 } 685 if (pti->pt_flags & PF_UCNTL && (c = pti->pt_ucntl)) { 686 pti->pt_ucntl = 0; 687 mutex_spin_exit(&tty_lock); 688 error = ureadc(c, uio); 689 if (error != 0) 690 return error; 691 return 0; 692 } 693 if (tp->t_outq.c_cc && !ISSET(tp->t_state, TS_TTSTOP)) 694 break; 695 } 696 if (!ISSET(tp->t_state, TS_CARR_ON)) { 697 error = 0; /* EOF */ 698 goto out; 699 } 700 if (flag & IO_NDELAY) { 701 error = EWOULDBLOCK; 702 goto out; 703 } 704 error = cv_wait_sig(&tp->t_outcvf, &tty_lock); 705 if (error != 0) 706 goto out; 707 } 708 709 if (pti->pt_flags & (PF_PKT|PF_UCNTL)) { 710 mutex_spin_exit(&tty_lock); 711 error = ureadc(0, uio); 712 mutex_spin_enter(&tty_lock); 713 if (error == 0 && !ISSET(tp->t_state, TS_ISOPEN)) 714 error = EIO; 715 } 716 while (uio->uio_resid > 0 && error == 0) { 717 cc = q_to_b(&tp->t_outq, bf, uimin(uio->uio_resid, BUFSIZ)); 718 if (cc <= 0) 719 break; 720 mutex_spin_exit(&tty_lock); 721 error = uiomove(bf, cc, uio); 722 mutex_spin_enter(&tty_lock); 723 if (error == 0 && !ISSET(tp->t_state, TS_ISOPEN)) 724 error = EIO; 725 } 726 ttypull(tp); 727 out: 728 mutex_spin_exit(&tty_lock); 729 return error; 730 } 731 732 733 int 734 ptcwrite(dev_t dev, struct uio *uio, int flag) 735 { 736 struct pt_softc *pti = pt_softc[minor(dev)]; 737 struct tty *tp = pti->pt_tty; 738 u_char *cp = NULL; 739 int cc = 0; 740 u_char locbuf[BUFSIZ]; 741 int cnt = 0; 742 int error = 0; 743 744 again: 745 mutex_spin_enter(&tty_lock); 746 if (!ISSET(tp->t_state, TS_ISOPEN)) 747 goto block; 748 if (pti->pt_flags & PF_REMOTE) { 749 if (tp->t_canq.c_cc) 750 goto block; 751 while (uio->uio_resid > 0 && tp->t_canq.c_cc < TTYHOG) { 752 if (cc == 0) { 753 cc = uimin(uio->uio_resid, BUFSIZ); 754 cc = uimin(cc, TTYHOG - tp->t_canq.c_cc); 755 cp = locbuf; 756 mutex_spin_exit(&tty_lock); 757 error = uiomove(cp, cc, uio); 758 if (error != 0) 759 return error; 760 mutex_spin_enter(&tty_lock); 761 /* check again for safety */ 762 if (!ISSET(tp->t_state, TS_ISOPEN)) { 763 /* 764 * adjust for data copied in but not 765 * written 766 */ 767 uio->uio_resid += cc; 768 error = EIO; 769 goto out; 770 } 771 } 772 if (cc) { 773 cc = b_to_q(cp, cc, &tp->t_outq); 774 if (cc > 0) 775 goto block; 776 } 777 } 778 (void) putc(0, &tp->t_canq); 779 ttwakeup(tp); 780 cv_broadcast(&tp->t_cancv); 781 error = 0; 782 goto out; 783 } 784 while (uio->uio_resid > 0) { 785 if (cc == 0) { 786 cc = uimin(uio->uio_resid, BUFSIZ); 787 cp = locbuf; 788 mutex_spin_exit(&tty_lock); 789 error = uiomove(cp, cc, uio); 790 if (error != 0) 791 return error; 792 mutex_spin_enter(&tty_lock); 793 /* check again for safety */ 794 if (!ISSET(tp->t_state, TS_ISOPEN)) { 795 /* adjust for data copied in but not written */ 796 uio->uio_resid += cc; 797 error = EIO; 798 goto out; 799 } 800 } 801 while (cc > 0) { 802 int used = tp->t_rawq.c_cc + tp->t_canq.c_cc; 803 int canon = ISSET(tp->t_lflag, ICANON) ? 1 : 0; 804 /* 805 * We need space for 2 characters if canonical 806 * because we might need to print ^C 807 */ 808 if (used >= (TTYHOG - canon) && 809 (tp->t_canq.c_cc > 0 || !canon)) { 810 cv_broadcast(&tp->t_rawcv); 811 goto block; 812 } 813 /* 814 * XXX - should change l_rint to be called with lock 815 * see also tty.c:ttyinput_wlock() 816 */ 817 mutex_spin_exit(&tty_lock); 818 (*tp->t_linesw->l_rint)(*cp++, tp); 819 mutex_spin_enter(&tty_lock); 820 cnt++; 821 cc--; 822 } 823 } 824 error = 0; 825 goto out; 826 827 block: 828 /* 829 * Come here to wait for slave to open, for space 830 * in outq, or space in rawq. 831 */ 832 if (!ISSET(tp->t_state, TS_CARR_ON)) { 833 /* adjust for data copied in but not written */ 834 uio->uio_resid += cc; 835 error = EIO; 836 goto out; 837 } 838 if (flag & IO_NDELAY) { 839 /* adjust for data copied in but not written */ 840 uio->uio_resid += cc; 841 error = cnt == 0 ? EWOULDBLOCK : 0; 842 goto out; 843 } 844 error = cv_wait_sig(&tp->t_rawcvf, &tty_lock); 845 mutex_spin_exit(&tty_lock); 846 if (error != 0) { 847 /* adjust for data copied in but not written */ 848 uio->uio_resid += cc; 849 return error; 850 } 851 goto again; 852 853 out: 854 mutex_spin_exit(&tty_lock); 855 return error; 856 } 857 858 int 859 ptcpoll(dev_t dev, int events, struct lwp *l) 860 { 861 struct pt_softc *pti = pt_softc[minor(dev)]; 862 struct tty *tp = pti->pt_tty; 863 int revents = 0; 864 865 mutex_spin_enter(&tty_lock); 866 867 if (events & (POLLIN | POLLRDNORM)) 868 if (ISSET(tp->t_state, TS_ISOPEN) && 869 ((tp->t_outq.c_cc > 0 && !ISSET(tp->t_state, TS_TTSTOP)) || 870 ((pti->pt_flags & PF_PKT) && pti->pt_send) || 871 ((pti->pt_flags & PF_UCNTL) && pti->pt_ucntl))) 872 revents |= events & (POLLIN | POLLRDNORM); 873 874 if (events & (POLLOUT | POLLWRNORM)) 875 if (ISSET(tp->t_state, TS_ISOPEN) && 876 ((pti->pt_flags & PF_REMOTE) ? 877 (tp->t_canq.c_cc == 0) : 878 ((tp->t_rawq.c_cc + tp->t_canq.c_cc < TTYHOG-2) || 879 (tp->t_canq.c_cc == 0 && ISSET(tp->t_lflag, ICANON))))) 880 revents |= events & (POLLOUT | POLLWRNORM); 881 882 if (events & POLLHUP) 883 if (!ISSET(tp->t_state, TS_CARR_ON)) 884 revents |= POLLHUP; 885 886 if (revents == 0) { 887 if (events & (POLLIN | POLLHUP | POLLRDNORM)) 888 selrecord(l, &pti->pt_selr); 889 890 if (events & (POLLOUT | POLLWRNORM)) 891 selrecord(l, &pti->pt_selw); 892 } 893 894 mutex_spin_exit(&tty_lock); 895 896 return revents; 897 } 898 899 static void 900 filt_ptcrdetach(struct knote *kn) 901 { 902 struct pt_softc *pti; 903 904 pti = kn->kn_hook; 905 906 mutex_spin_enter(&tty_lock); 907 selremove_knote(&pti->pt_selr, kn); 908 mutex_spin_exit(&tty_lock); 909 } 910 911 static int 912 filt_ptcread(struct knote *kn, long hint) 913 { 914 struct pt_softc *pti; 915 struct tty *tp; 916 int canread; 917 918 pti = kn->kn_hook; 919 tp = pti->pt_tty; 920 921 if ((hint & NOTE_SUBMIT) == 0) { 922 mutex_spin_enter(&tty_lock); 923 } 924 925 canread = (ISSET(tp->t_state, TS_ISOPEN) && 926 ((tp->t_outq.c_cc > 0 && !ISSET(tp->t_state, TS_TTSTOP)) || 927 ((pti->pt_flags & PF_PKT) && pti->pt_send) || 928 ((pti->pt_flags & PF_UCNTL) && pti->pt_ucntl))); 929 930 if (canread) { 931 /* 932 * c_cc is number of characters after output post-processing; 933 * the amount of data actually read(2) depends on 934 * setting of input flags for the terminal. 935 */ 936 kn->kn_data = tp->t_outq.c_cc; 937 if (((pti->pt_flags & PF_PKT) && pti->pt_send) || 938 ((pti->pt_flags & PF_UCNTL) && pti->pt_ucntl)) 939 kn->kn_data++; 940 } 941 if (!ISSET(tp->t_state, TS_CARR_ON)) { 942 knote_set_eof(kn, 0); 943 canread = 1; 944 } 945 946 if ((hint & NOTE_SUBMIT) == 0) { 947 mutex_spin_exit(&tty_lock); 948 } 949 950 return canread; 951 } 952 953 static void 954 filt_ptcwdetach(struct knote *kn) 955 { 956 struct pt_softc *pti; 957 958 pti = kn->kn_hook; 959 960 mutex_spin_enter(&tty_lock); 961 selremove_knote(&pti->pt_selw, kn); 962 mutex_spin_exit(&tty_lock); 963 } 964 965 static int 966 filt_ptcwrite(struct knote *kn, long hint) 967 { 968 struct pt_softc *pti; 969 struct tty *tp; 970 int canwrite; 971 int nwrite; 972 973 pti = kn->kn_hook; 974 tp = pti->pt_tty; 975 976 if ((hint & NOTE_SUBMIT) == 0) { 977 mutex_spin_enter(&tty_lock); 978 } 979 980 canwrite = (ISSET(tp->t_state, TS_ISOPEN) && 981 ((pti->pt_flags & PF_REMOTE) ? 982 (tp->t_canq.c_cc == 0) : 983 ((tp->t_rawq.c_cc + tp->t_canq.c_cc < TTYHOG-2) || 984 (tp->t_canq.c_cc == 0 && ISSET(tp->t_lflag, ICANON))))); 985 986 if (canwrite) { 987 if (pti->pt_flags & PF_REMOTE) 988 nwrite = tp->t_canq.c_cn; 989 else { 990 /* this is guaranteed to be > 0 due to above check */ 991 nwrite = tp->t_canq.c_cn 992 - (tp->t_rawq.c_cc + tp->t_canq.c_cc); 993 } 994 kn->kn_data = nwrite; 995 } 996 997 if ((hint & NOTE_SUBMIT) == 0) { 998 mutex_spin_exit(&tty_lock); 999 } 1000 1001 return canwrite; 1002 } 1003 1004 static const struct filterops ptcread_filtops = { 1005 .f_flags = FILTEROP_ISFD | FILTEROP_MPSAFE, 1006 .f_attach = NULL, 1007 .f_detach = filt_ptcrdetach, 1008 .f_event = filt_ptcread, 1009 }; 1010 1011 static const struct filterops ptcwrite_filtops = { 1012 .f_flags = FILTEROP_ISFD | FILTEROP_MPSAFE, 1013 .f_attach = NULL, 1014 .f_detach = filt_ptcwdetach, 1015 .f_event = filt_ptcwrite, 1016 }; 1017 1018 int 1019 ptckqfilter(dev_t dev, struct knote *kn) 1020 { 1021 struct pt_softc *pti = pt_softc[minor(dev)]; 1022 struct selinfo *sip; 1023 1024 switch (kn->kn_filter) { 1025 case EVFILT_READ: 1026 sip = &pti->pt_selr; 1027 kn->kn_fop = &ptcread_filtops; 1028 break; 1029 case EVFILT_WRITE: 1030 sip = &pti->pt_selw; 1031 kn->kn_fop = &ptcwrite_filtops; 1032 break; 1033 default: 1034 return EINVAL; 1035 } 1036 1037 kn->kn_hook = pti; 1038 1039 mutex_spin_enter(&tty_lock); 1040 selrecord_knote(sip, kn); 1041 mutex_spin_exit(&tty_lock); 1042 1043 return 0; 1044 } 1045 1046 struct tty * 1047 ptytty(dev_t dev) 1048 { 1049 struct pt_softc *pti = pt_softc[minor(dev)]; 1050 struct tty *tp = pti->pt_tty; 1051 1052 return tp; 1053 } 1054 1055 /*ARGSUSED*/ 1056 int 1057 ptyioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l) 1058 { 1059 struct pt_softc *pti = pt_softc[minor(dev)]; 1060 struct tty *tp = pti->pt_tty; 1061 const struct cdevsw *cdev; 1062 u_char *cc = tp->t_cc; 1063 int stop, error, sig; 1064 #ifndef NO_DEV_PTM 1065 struct mount *mp; 1066 #endif 1067 1068 /* 1069 * IF CONTROLLER STTY THEN MUST FLUSH TO PREVENT A HANG. 1070 * ttywflush(tp) will hang if there are characters in the outq. 1071 */ 1072 if (cmd == TIOCEXT) { 1073 /* 1074 * When the EXTPROC bit is being toggled, we need 1075 * to send an TIOCPKT_IOCTL if the packet driver 1076 * is turned on. 1077 */ 1078 if (*(int *)data) { 1079 if (pti->pt_flags & PF_PKT) { 1080 pti->pt_send |= TIOCPKT_IOCTL; 1081 ptcwakeup(tp, FREAD); 1082 } 1083 SET(tp->t_lflag, EXTPROC); 1084 } else { 1085 if (ISSET(tp->t_lflag, EXTPROC) && 1086 (pti->pt_flags & PF_PKT)) { 1087 pti->pt_send |= TIOCPKT_IOCTL; 1088 ptcwakeup(tp, FREAD); 1089 } 1090 CLR(tp->t_lflag, EXTPROC); 1091 } 1092 return(0); 1093 } 1094 1095 #ifndef NO_DEV_PTM 1096 /* Allow getting the name from either the master or the slave */ 1097 if (cmd == TIOCPTSNAME) { 1098 if ((error = pty_getmp(l, &mp)) != 0) 1099 return error; 1100 return pty_fill_ptmget(l, dev, -1, -1, data, mp); 1101 } 1102 #endif 1103 1104 cdev = cdevsw_lookup(dev); 1105 if (cdev != NULL && cdev->d_open == ptcopen) 1106 switch (cmd) { 1107 #ifndef NO_DEV_PTM 1108 case TIOCGRANTPT: 1109 if ((error = pty_getmp(l, &mp)) != 0) 1110 return error; 1111 return pty_grant_slave(l, dev, mp); 1112 #endif 1113 1114 case TIOCGPGRP: 1115 /* 1116 * We avoid calling ttioctl on the controller since, 1117 * in that case, tp must be the controlling terminal. 1118 */ 1119 *(int *)data = tp->t_pgrp ? tp->t_pgrp->pg_id : 0; 1120 return 0; 1121 1122 case TIOCPKT: 1123 if (*(int *)data) { 1124 if (pti->pt_flags & PF_UCNTL) 1125 return EINVAL; 1126 pti->pt_flags |= PF_PKT; 1127 } else 1128 pti->pt_flags &= ~PF_PKT; 1129 return 0; 1130 1131 case TIOCUCNTL: 1132 if (*(int *)data) { 1133 if (pti->pt_flags & PF_PKT) 1134 return EINVAL; 1135 pti->pt_flags |= PF_UCNTL; 1136 } else 1137 pti->pt_flags &= ~PF_UCNTL; 1138 return 0; 1139 1140 case TIOCREMOTE: 1141 if (*(int *)data) 1142 pti->pt_flags |= PF_REMOTE; 1143 else 1144 pti->pt_flags &= ~PF_REMOTE; 1145 mutex_spin_enter(&tty_lock); 1146 ttyflush(tp, FREAD|FWRITE); 1147 mutex_spin_exit(&tty_lock); 1148 return 0; 1149 1150 case TIOCSETP: 1151 case TIOCSETN: 1152 case TIOCSETD: 1153 case TIOCSETA: 1154 case TIOCSETAW: 1155 case TIOCSETAF: 1156 mutex_spin_enter(&tty_lock); 1157 ndflush(&tp->t_outq, tp->t_outq.c_cc); 1158 mutex_spin_exit(&tty_lock); 1159 break; 1160 1161 case TIOCSIG: 1162 sig = (int)(long)*(void **)data; 1163 if (sig <= 0 || sig >= NSIG) 1164 return EINVAL; 1165 mutex_spin_enter(&tty_lock); 1166 if (!ISSET(tp->t_lflag, NOFLSH)) 1167 ttyflush(tp, FREAD|FWRITE); 1168 tp->t_state |= TS_SIGINFO; 1169 ttysig(tp, TTYSIG_PG1, sig); 1170 mutex_spin_exit(&tty_lock); 1171 return 0; 1172 1173 case FIONREAD: 1174 mutex_spin_enter(&tty_lock); 1175 *(int *)data = tp->t_outq.c_cc; 1176 mutex_spin_exit(&tty_lock); 1177 return 0; 1178 } 1179 1180 error = (*tp->t_linesw->l_ioctl)(tp, cmd, data, flag, l); 1181 if (error == EPASSTHROUGH) 1182 error = ttioctl(tp, cmd, data, flag, l); 1183 if (error == EPASSTHROUGH) { 1184 if (pti->pt_flags & PF_UCNTL && 1185 (cmd & ~0xff) == UIOCCMD(0)) { 1186 if (cmd & 0xff) { 1187 pti->pt_ucntl = (u_char)cmd; 1188 ptcwakeup(tp, FREAD); 1189 } 1190 return 0; 1191 } 1192 } 1193 /* 1194 * If external processing and packet mode send ioctl packet. 1195 */ 1196 if (ISSET(tp->t_lflag, EXTPROC) && (pti->pt_flags & PF_PKT)) { 1197 switch(cmd) { 1198 case TIOCSETA: 1199 case TIOCSETAW: 1200 case TIOCSETAF: 1201 case TIOCSETP: 1202 case TIOCSETN: 1203 case TIOCSETC: 1204 case TIOCSLTC: 1205 case TIOCLBIS: 1206 case TIOCLBIC: 1207 case TIOCLSET: 1208 pti->pt_send |= TIOCPKT_IOCTL; 1209 ptcwakeup(tp, FREAD); 1210 default: 1211 break; 1212 } 1213 } 1214 stop = ISSET(tp->t_iflag, IXON) && CCEQ(cc[VSTOP], CTRL('s')) 1215 && CCEQ(cc[VSTART], CTRL('q')); 1216 if (pti->pt_flags & PF_NOSTOP) { 1217 if (stop) { 1218 pti->pt_send &= ~TIOCPKT_NOSTOP; 1219 pti->pt_send |= TIOCPKT_DOSTOP; 1220 pti->pt_flags &= ~PF_NOSTOP; 1221 ptcwakeup(tp, FREAD); 1222 } 1223 } else { 1224 if (!stop) { 1225 pti->pt_send &= ~TIOCPKT_DOSTOP; 1226 pti->pt_send |= TIOCPKT_NOSTOP; 1227 pti->pt_flags |= PF_NOSTOP; 1228 ptcwakeup(tp, FREAD); 1229 } 1230 } 1231 return error; 1232 } 1233
Indexes created Sat Sep 20 22:09:52 GMT 2025