1 /* 2 * Copyright (c) 1982, 1986, 1989 The Regents of the University of California. 3 * All rights reserved. 4 * 5 * %sccs.include.redist.c% 6 * 7 * @(#)tty_pty.c 7.23 (Berkeley) 02/05/92 8 */ 9 10 /* 11 * Pseudo-teletype Driver 12 * (Actually two drivers, requiring two entries in 'cdevsw') 13 */ 14 #include "pty.h" 15 16 #if NPTY > 0 17 #include "param.h" 18 #include "systm.h" 19 #include "ioctl.h" 20 #include "tty.h" 21 #include "conf.h" 22 #include "file.h" 23 #include "proc.h" 24 #include "uio.h" 25 #include "kernel.h" 26 #include "vnode.h" 27 28 #if NPTY == 1 29 #undef NPTY 30 #define NPTY 32 /* crude XXX */ 31 #endif 32 33 #define BUFSIZ 100 /* Chunk size iomoved to/from user */ 34 35 /* 36 * pts == /dev/tty[pqrs]? 37 * ptc == /dev/pty[pqrs]? 38 */ 39 struct tty pt_tty[NPTY]; 40 struct pt_ioctl { 41 int pt_flags; 42 struct proc *pt_selr, *pt_selw; 43 u_char pt_send; 44 u_char pt_ucntl; 45 } pt_ioctl[NPTY]; 46 int npty = NPTY; /* for pstat -t */ 47 48 #define PF_RCOLL 0x01 49 #define PF_WCOLL 0x02 50 #define PF_PKT 0x08 /* packet mode */ 51 #define PF_STOPPED 0x10 /* user told stopped */ 52 #define PF_REMOTE 0x20 /* remote and flow controlled input */ 53 #define PF_NOSTOP 0x40 54 #define PF_UCNTL 0x80 /* user control mode */ 55 56 void ptsstop __P((struct tty *, int)); 57 58 /*ARGSUSED*/ 59 ptsopen(dev, flag, devtype, p) 60 dev_t dev; 61 int flag, devtype; 62 struct proc *p; 63 { 64 register struct tty *tp; 65 int error; 66 67 #ifdef lint 68 npty = npty; 69 #endif 70 if (minor(dev) >= NPTY) 71 return (ENXIO); 72 tp = &pt_tty[minor(dev)]; 73 if ((tp->t_state & TS_ISOPEN) == 0) { 74 tp->t_state |= TS_WOPEN; 75 ttychars(tp); /* Set up default chars */ 76 tp->t_iflag = TTYDEF_IFLAG; 77 tp->t_oflag = TTYDEF_OFLAG; 78 tp->t_lflag = TTYDEF_LFLAG; 79 tp->t_cflag = TTYDEF_CFLAG; 80 tp->t_ispeed = tp->t_ospeed = TTYDEF_SPEED; 81 ttsetwater(tp); /* would be done in xxparam() */ 82 } else if (tp->t_state&TS_XCLUDE && p->p_ucred->cr_uid != 0) 83 return (EBUSY); 84 if (tp->t_oproc) /* Ctrlr still around. */ 85 tp->t_state |= TS_CARR_ON; 86 while ((tp->t_state & TS_CARR_ON) == 0) { 87 tp->t_state |= TS_WOPEN; 88 if (flag&FNONBLOCK) 89 break; 90 if (error = ttysleep(tp, (caddr_t)&tp->t_rawq, TTIPRI | PCATCH, 91 ttopen, 0)) 92 return (error); 93 } 94 error = (*linesw[tp->t_line].l_open)(dev, tp); 95 ptcwakeup(tp, FREAD|FWRITE); 96 return (error); 97 } 98 99 ptsclose(dev, flag, mode, p) 100 dev_t dev; 101 int flag, mode; 102 struct proc *p; 103 { 104 register struct tty *tp; 105 106 tp = &pt_tty[minor(dev)]; 107 (*linesw[tp->t_line].l_close)(tp, flag); 108 ttyclose(tp); 109 ptcwakeup(tp, FREAD|FWRITE); 110 } 111 112 ptsread(dev, uio, flag) 113 dev_t dev; 114 struct uio *uio; 115 int flag; 116 { 117 struct proc *p = curproc; 118 register struct tty *tp = &pt_tty[minor(dev)]; 119 register struct pt_ioctl *pti = &pt_ioctl[minor(dev)]; 120 int error = 0; 121 122 again: 123 if (pti->pt_flags & PF_REMOTE) { 124 while (isbackground(p, tp)) { 125 if ((p->p_sigignore & sigmask(SIGTTIN)) || 126 (p->p_sigmask & sigmask(SIGTTIN)) || 127 p->p_pgrp->pg_jobc == 0 || 128 p->p_flag&SPPWAIT) 129 return (EIO); 130 pgsignal(p->p_pgrp, SIGTTIN, 1); 131 if (error = ttysleep(tp, (caddr_t)&lbolt, 132 TTIPRI | PCATCH, ttybg, 0)) 133 return (error); 134 } 135 if (tp->t_canq.c_cc == 0) { 136 if (flag & IO_NDELAY) 137 return (EWOULDBLOCK); 138 if (error = ttysleep(tp, (caddr_t)&tp->t_canq, 139 TTIPRI | PCATCH, ttyin, 0)) 140 return (error); 141 goto again; 142 } 143 while (tp->t_canq.c_cc > 1 && uio->uio_resid > 0) 144 if (ureadc(getc(&tp->t_canq), uio) < 0) { 145 error = EFAULT; 146 break; 147 } 148 if (tp->t_canq.c_cc == 1) 149 (void) getc(&tp->t_canq); 150 if (tp->t_canq.c_cc) 151 return (error); 152 } else 153 if (tp->t_oproc) 154 error = (*linesw[tp->t_line].l_read)(tp, uio, flag); 155 ptcwakeup(tp, FWRITE); 156 return (error); 157 } 158 159 /* 160 * Write to pseudo-tty. 161 * Wakeups of controlling tty will happen 162 * indirectly, when tty driver calls ptsstart. 163 */ 164 ptswrite(dev, uio, flag) 165 dev_t dev; 166 struct uio *uio; 167 { 168 register struct tty *tp; 169 170 tp = &pt_tty[minor(dev)]; 171 if (tp->t_oproc == 0) 172 return (EIO); 173 return ((*linesw[tp->t_line].l_write)(tp, uio, flag)); 174 } 175 176 /* 177 * Start output on pseudo-tty. 178 * Wake up process selecting or sleeping for input from controlling tty. 179 */ 180 void 181 ptsstart(tp) 182 struct tty *tp; 183 { 184 register struct pt_ioctl *pti = &pt_ioctl[minor(tp->t_dev)]; 185 186 if (tp->t_state & TS_TTSTOP) 187 return; 188 if (pti->pt_flags & PF_STOPPED) { 189 pti->pt_flags &= ~PF_STOPPED; 190 pti->pt_send = TIOCPKT_START; 191 } 192 ptcwakeup(tp, FREAD); 193 } 194 195 ptcwakeup(tp, flag) 196 struct tty *tp; 197 int flag; 198 { 199 struct pt_ioctl *pti = &pt_ioctl[minor(tp->t_dev)]; 200 201 if (flag & FREAD) { 202 if (pti->pt_selr) { 203 selwakeup(pti->pt_selr, pti->pt_flags & PF_RCOLL); 204 pti->pt_selr = 0; 205 pti->pt_flags &= ~PF_RCOLL; 206 } 207 wakeup((caddr_t)&tp->t_outq.c_cf); 208 } 209 if (flag & FWRITE) { 210 if (pti->pt_selw) { 211 selwakeup(pti->pt_selw, pti->pt_flags & PF_WCOLL); 212 pti->pt_selw = 0; 213 pti->pt_flags &= ~PF_WCOLL; 214 } 215 wakeup((caddr_t)&tp->t_rawq.c_cf); 216 } 217 } 218 219 /*ARGSUSED*/ 220 #ifdef __STDC__ 221 ptcopen(dev_t dev, int flag, int devtype, struct proc *p) 222 #else 223 ptcopen(dev, flag, devtype, p) 224 dev_t dev; 225 int flag, devtype; 226 struct proc *p; 227 #endif 228 { 229 register struct tty *tp; 230 struct pt_ioctl *pti; 231 232 if (minor(dev) >= NPTY) 233 return (ENXIO); 234 tp = &pt_tty[minor(dev)]; 235 if (tp->t_oproc) 236 return (EIO); 237 tp->t_oproc = ptsstart; 238 #ifdef sun4c 239 tp->t_stop = ptsstop; 240 #endif 241 (void)(*linesw[tp->t_line].l_modem)(tp, 1); 242 tp->t_lflag &= ~EXTPROC; 243 pti = &pt_ioctl[minor(dev)]; 244 pti->pt_flags = 0; 245 pti->pt_send = 0; 246 pti->pt_ucntl = 0; 247 return (0); 248 } 249 250 ptcclose(dev) 251 dev_t dev; 252 { 253 register struct tty *tp; 254 255 tp = &pt_tty[minor(dev)]; 256 (void)(*linesw[tp->t_line].l_modem)(tp, 0); 257 tp->t_state &= ~TS_CARR_ON; 258 tp->t_oproc = 0; /* mark closed */ 259 tp->t_session = 0; 260 } 261 262 ptcread(dev, uio, flag) 263 dev_t dev; 264 struct uio *uio; 265 int flag; 266 { 267 register struct tty *tp = &pt_tty[minor(dev)]; 268 struct pt_ioctl *pti = &pt_ioctl[minor(dev)]; 269 char buf[BUFSIZ]; 270 int error = 0, cc; 271 272 /* 273 * We want to block until the slave 274 * is open, and there's something to read; 275 * but if we lost the slave or we're NBIO, 276 * then return the appropriate error instead. 277 */ 278 for (;;) { 279 if (tp->t_state&TS_ISOPEN) { 280 if (pti->pt_flags&PF_PKT && pti->pt_send) { 281 error = ureadc((int)pti->pt_send, uio); 282 if (error) 283 return (error); 284 if (pti->pt_send & TIOCPKT_IOCTL) { 285 cc = MIN(uio->uio_resid, 286 sizeof(tp->t_termios)); 287 uiomove(&tp->t_termios, cc, uio); 288 } 289 pti->pt_send = 0; 290 return (0); 291 } 292 if (pti->pt_flags&PF_UCNTL && pti->pt_ucntl) { 293 error = ureadc((int)pti->pt_ucntl, uio); 294 if (error) 295 return (error); 296 pti->pt_ucntl = 0; 297 return (0); 298 } 299 if (tp->t_outq.c_cc && (tp->t_state&TS_TTSTOP) == 0) 300 break; 301 } 302 if ((tp->t_state&TS_CARR_ON) == 0) 303 return (0); /* EOF */ 304 if (flag & IO_NDELAY) 305 return (EWOULDBLOCK); 306 if (error = tsleep((caddr_t)&tp->t_outq.c_cf, TTIPRI | PCATCH, 307 ttyin, 0)) 308 return (error); 309 } 310 if (pti->pt_flags & (PF_PKT|PF_UCNTL)) 311 error = ureadc(0, uio); 312 while (uio->uio_resid > 0 && error == 0) { 313 cc = q_to_b(&tp->t_outq, buf, MIN(uio->uio_resid, BUFSIZ)); 314 if (cc <= 0) 315 break; 316 error = uiomove(buf, cc, uio); 317 } 318 if (tp->t_outq.c_cc <= tp->t_lowat) { 319 if (tp->t_state&TS_ASLEEP) { 320 tp->t_state &= ~TS_ASLEEP; 321 wakeup((caddr_t)&tp->t_outq); 322 } 323 if (tp->t_wsel) { 324 selwakeup(tp->t_wsel, tp->t_state & TS_WCOLL); 325 tp->t_wsel = 0; 326 tp->t_state &= ~TS_WCOLL; 327 } 328 } 329 return (error); 330 } 331 332 void 333 ptsstop(tp, flush) 334 register struct tty *tp; 335 int flush; 336 { 337 struct pt_ioctl *pti = &pt_ioctl[minor(tp->t_dev)]; 338 int flag; 339 340 /* note: FLUSHREAD and FLUSHWRITE already ok */ 341 if (flush == 0) { 342 flush = TIOCPKT_STOP; 343 pti->pt_flags |= PF_STOPPED; 344 } else 345 pti->pt_flags &= ~PF_STOPPED; 346 pti->pt_send |= flush; 347 /* change of perspective */ 348 flag = 0; 349 if (flush & FREAD) 350 flag |= FWRITE; 351 if (flush & FWRITE) 352 flag |= FREAD; 353 ptcwakeup(tp, flag); 354 } 355 356 ptcselect(dev, rw, p) 357 dev_t dev; 358 int rw; 359 struct proc *p; 360 { 361 register struct tty *tp = &pt_tty[minor(dev)]; 362 struct pt_ioctl *pti = &pt_ioctl[minor(dev)]; 363 struct proc *prev; 364 int s; 365 366 if ((tp->t_state&TS_CARR_ON) == 0) 367 return (1); 368 switch (rw) { 369 370 case FREAD: 371 /* 372 * Need to block timeouts (ttrstart). 373 */ 374 s = spltty(); 375 if ((tp->t_state&TS_ISOPEN) && 376 tp->t_outq.c_cc && (tp->t_state&TS_TTSTOP) == 0) { 377 splx(s); 378 return (1); 379 } 380 splx(s); 381 /* FALLTHROUGH */ 382 383 case 0: /* exceptional */ 384 if ((tp->t_state&TS_ISOPEN) && 385 (pti->pt_flags&PF_PKT && pti->pt_send || 386 pti->pt_flags&PF_UCNTL && pti->pt_ucntl)) 387 return (1); 388 if ((prev = pti->pt_selr) && prev->p_wchan == (caddr_t)&selwait) 389 pti->pt_flags |= PF_RCOLL; 390 else 391 pti->pt_selr = p; 392 break; 393 394 395 case FWRITE: 396 if (tp->t_state&TS_ISOPEN) { 397 if (pti->pt_flags & PF_REMOTE) { 398 if (tp->t_canq.c_cc == 0) 399 return (1); 400 } else { 401 if (tp->t_rawq.c_cc + tp->t_canq.c_cc < TTYHOG-2) 402 return (1); 403 if (tp->t_canq.c_cc == 0 && (tp->t_iflag&ICANON)) 404 return (1); 405 } 406 } 407 if ((prev = pti->pt_selw) && prev->p_wchan == (caddr_t)&selwait) 408 pti->pt_flags |= PF_WCOLL; 409 else 410 pti->pt_selw = p; 411 break; 412 413 } 414 return (0); 415 } 416 417 ptcwrite(dev, uio, flag) 418 dev_t dev; 419 register struct uio *uio; 420 { 421 register struct tty *tp = &pt_tty[minor(dev)]; 422 register u_char *cp; 423 register int cc = 0; 424 u_char locbuf[BUFSIZ]; 425 int cnt = 0; 426 struct pt_ioctl *pti = &pt_ioctl[minor(dev)]; 427 int error = 0; 428 429 again: 430 if ((tp->t_state&TS_ISOPEN) == 0) 431 goto block; 432 if (pti->pt_flags & PF_REMOTE) { 433 if (tp->t_canq.c_cc) 434 goto block; 435 while (uio->uio_resid > 0 && tp->t_canq.c_cc < TTYHOG - 1) { 436 if (cc == 0) { 437 cc = min(uio->uio_resid, BUFSIZ); 438 cc = min(cc, TTYHOG - 1 - tp->t_canq.c_cc); 439 cp = locbuf; 440 error = uiomove((caddr_t)cp, cc, uio); 441 if (error) 442 return (error); 443 /* check again for safety */ 444 if ((tp->t_state&TS_ISOPEN) == 0) 445 return (EIO); 446 } 447 if (cc) 448 (void) b_to_q((char *)cp, cc, &tp->t_canq); 449 cc = 0; 450 } 451 (void) putc(0, &tp->t_canq); 452 ttwakeup(tp); 453 wakeup((caddr_t)&tp->t_canq); 454 return (0); 455 } 456 while (uio->uio_resid > 0) { 457 if (cc == 0) { 458 cc = min(uio->uio_resid, BUFSIZ); 459 cp = locbuf; 460 error = uiomove((caddr_t)cp, cc, uio); 461 if (error) 462 return (error); 463 /* check again for safety */ 464 if ((tp->t_state&TS_ISOPEN) == 0) 465 return (EIO); 466 } 467 while (cc > 0) { 468 if ((tp->t_rawq.c_cc + tp->t_canq.c_cc) >= TTYHOG - 2 && 469 (tp->t_canq.c_cc > 0 || !(tp->t_iflag&ICANON))) { 470 wakeup((caddr_t)&tp->t_rawq); 471 goto block; 472 } 473 (*linesw[tp->t_line].l_rint)(*cp++, tp); 474 cnt++; 475 cc--; 476 } 477 cc = 0; 478 } 479 return (0); 480 block: 481 /* 482 * Come here to wait for slave to open, for space 483 * in outq, or space in rawq. 484 */ 485 if ((tp->t_state&TS_CARR_ON) == 0) 486 return (EIO); 487 if (flag & IO_NDELAY) { 488 /* adjust for data copied in but not written */ 489 uio->uio_resid += cc; 490 if (cnt == 0) 491 return (EWOULDBLOCK); 492 return (0); 493 } 494 if (error = tsleep((caddr_t)&tp->t_rawq.c_cf, TTOPRI | PCATCH, 495 ttyout, 0)) { 496 /* adjust for data copied in but not written */ 497 uio->uio_resid += cc; 498 return (error); 499 } 500 goto again; 501 } 502 503 /*ARGSUSED*/ 504 ptyioctl(dev, cmd, data, flag, p) 505 dev_t dev; 506 int cmd; 507 caddr_t data; 508 int flag; 509 struct proc *p; 510 { 511 register struct tty *tp = &pt_tty[minor(dev)]; 512 register struct pt_ioctl *pti = &pt_ioctl[minor(dev)]; 513 register u_char *cc = tp->t_cc; 514 int stop, error; 515 516 /* 517 * IF CONTROLLER STTY THEN MUST FLUSH TO PREVENT A HANG. 518 * ttywflush(tp) will hang if there are characters in the outq. 519 */ 520 if (cmd == TIOCEXT) { 521 /* 522 * When the EXTPROC bit is being toggled, we need 523 * to send an TIOCPKT_IOCTL if the packet driver 524 * is turned on. 525 */ 526 if (*(int *)data) { 527 if (pti->pt_flags & PF_PKT) { 528 pti->pt_send |= TIOCPKT_IOCTL; 529 ptcwakeup(tp); 530 } 531 tp->t_lflag |= EXTPROC; 532 } else { 533 if ((tp->t_state & EXTPROC) && 534 (pti->pt_flags & PF_PKT)) { 535 pti->pt_send |= TIOCPKT_IOCTL; 536 ptcwakeup(tp); 537 } 538 tp->t_lflag &= ~EXTPROC; 539 } 540 return(0); 541 } else 542 if (cdevsw[major(dev)].d_open == ptcopen) 543 switch (cmd) { 544 545 case TIOCGPGRP: 546 /* 547 * We aviod calling ttioctl on the controller since, 548 * in that case, tp must be the controlling terminal. 549 */ 550 *(int *)data = tp->t_pgrp ? tp->t_pgrp->pg_id : 0; 551 return (0); 552 553 case TIOCPKT: 554 if (*(int *)data) { 555 if (pti->pt_flags & PF_UCNTL) 556 return (EINVAL); 557 pti->pt_flags |= PF_PKT; 558 } else 559 pti->pt_flags &= ~PF_PKT; 560 return (0); 561 562 case TIOCUCNTL: 563 if (*(int *)data) { 564 if (pti->pt_flags & PF_PKT) 565 return (EINVAL); 566 pti->pt_flags |= PF_UCNTL; 567 } else 568 pti->pt_flags &= ~PF_UCNTL; 569 return (0); 570 571 case TIOCREMOTE: 572 if (*(int *)data) 573 pti->pt_flags |= PF_REMOTE; 574 else 575 pti->pt_flags &= ~PF_REMOTE; 576 ttyflush(tp, FREAD|FWRITE); 577 return (0); 578 579 #ifdef COMPAT_43 580 case TIOCSETP: 581 case TIOCSETN: 582 #endif 583 case TIOCSETD: 584 case TIOCSETA: 585 case TIOCSETAW: 586 case TIOCSETAF: 587 ndflush(&tp->t_outq, tp->t_outq.c_cc); 588 break; 589 590 case TIOCSIG: 591 if (*(unsigned int *)data >= NSIG) 592 return(EINVAL); 593 if ((tp->t_lflag&NOFLSH) == 0) 594 ttyflush(tp, FREAD|FWRITE); 595 pgsignal(tp->t_pgrp, *(unsigned int *)data, 1); 596 if ((*(unsigned int *)data == SIGINFO) && 597 ((tp->t_lflag&NOKERNINFO) == 0)) 598 ttyinfo(tp); 599 return(0); 600 } 601 error = (*linesw[tp->t_line].l_ioctl)(tp, cmd, data, flag, p); 602 if (error < 0) 603 error = ttioctl(tp, cmd, data, flag); 604 if (error < 0) { 605 if (pti->pt_flags & PF_UCNTL && 606 (cmd & ~0xff) == UIOCCMD(0)) { 607 if (cmd & 0xff) { 608 pti->pt_ucntl = (u_char)cmd; 609 ptcwakeup(tp, FREAD); 610 } 611 return (0); 612 } 613 error = ENOTTY; 614 } 615 /* 616 * If external processing and packet mode send ioctl packet. 617 */ 618 if ((tp->t_lflag&EXTPROC) && (pti->pt_flags & PF_PKT)) { 619 switch(cmd) { 620 case TIOCSETA: 621 case TIOCSETAW: 622 case TIOCSETAF: 623 #ifdef COMPAT_43 624 case TIOCSETP: 625 case TIOCSETN: 626 #endif 627 #if defined(COMPAT_43) || defined(COMPAT_SUNOS) 628 case TIOCSETC: 629 case TIOCSLTC: 630 case TIOCLBIS: 631 case TIOCLBIC: 632 case TIOCLSET: 633 #endif 634 pti->pt_send |= TIOCPKT_IOCTL; 635 default: 636 break; 637 } 638 } 639 stop = (tp->t_iflag & IXON) && CCEQ(cc[VSTOP], CTRL('s')) 640 && CCEQ(cc[VSTART], CTRL('q')); 641 if (pti->pt_flags & PF_NOSTOP) { 642 if (stop) { 643 pti->pt_send &= ~TIOCPKT_NOSTOP; 644 pti->pt_send |= TIOCPKT_DOSTOP; 645 pti->pt_flags &= ~PF_NOSTOP; 646 ptcwakeup(tp, FREAD); 647 } 648 } else { 649 if (!stop) { 650 pti->pt_send &= ~TIOCPKT_DOSTOP; 651 pti->pt_send |= TIOCPKT_NOSTOP; 652 pti->pt_flags |= PF_NOSTOP; 653 ptcwakeup(tp, FREAD); 654 } 655 } 656 return (error); 657 } 658 #endif 659