1 /* 2 * Copyright (c) 1982, 1986, 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * %sccs.include.redist.c% 6 * 7 * @(#)tty_pty.c 8.4 (Berkeley) 02/20/95 8 */ 9 10 /* 11 * Pseudo-teletype Driver 12 * (Actually two drivers, requiring two entries in 'cdevsw') 13 */ 14 #include "pty.h" /* XXX */ 15 16 #include <sys/param.h> 17 #include <sys/systm.h> 18 #include <sys/ioctl.h> 19 #include <sys/proc.h> 20 #include <sys/tty.h> 21 #include <sys/conf.h> 22 #include <sys/file.h> 23 #include <sys/uio.h> 24 #include <sys/kernel.h> 25 #include <sys/vnode.h> 26 27 #if NPTY == 1 28 #undef NPTY 29 #define NPTY 32 /* crude XXX */ 30 #endif 31 32 #define BUFSIZ 100 /* Chunk size iomoved to/from user */ 33 34 /* 35 * pts == /dev/tty[pqrs]? 36 * ptc == /dev/pty[pqrs]? 37 */ 38 struct tty pt_tty[NPTY]; /* XXX */ 39 struct pt_ioctl { 40 int pt_flags; 41 struct selinfo pt_selr, pt_selw; 42 u_char pt_send; 43 u_char pt_ucntl; 44 } pt_ioctl[NPTY]; /* XXX */ 45 int npty = NPTY; /* for pstat -t */ 46 47 #define PF_PKT 0x08 /* packet mode */ 48 #define PF_STOPPED 0x10 /* user told stopped */ 49 #define PF_REMOTE 0x20 /* remote and flow controlled input */ 50 #define PF_NOSTOP 0x40 51 #define PF_UCNTL 0x80 /* user control mode */ 52 53 void ptsstop __P((struct tty *, int)); 54 55 /* 56 * Establish n (or default if n is 1) ptys in the system. 57 * 58 * XXX cdevsw & pstat require the array `pty[]' to be an array 59 */ 60 void 61 ptyattach(n) 62 int n; 63 { 64 #ifdef notyet 65 char *mem; 66 register u_long ntb; 67 #define DEFAULT_NPTY 32 68 69 /* maybe should allow 0 => none? */ 70 if (n <= 1) 71 n = DEFAULT_NPTY; 72 ntb = n * sizeof(struct tty); 73 mem = malloc(ntb + ALIGNBYTES + n * sizeof(struct pt_ioctl), 74 M_DEVBUF, M_WAITOK); 75 pt_tty = (struct tty *)mem; 76 mem = (char *)ALIGN(mem + ntb); 77 pt_ioctl = (struct pt_ioctl *)mem; 78 npty = n; 79 #endif 80 } 81 82 /*ARGSUSED*/ 83 ptsopen(dev, flag, devtype, p) 84 dev_t dev; 85 int flag, devtype; 86 struct proc *p; 87 { 88 register struct tty *tp; 89 int error; 90 91 if (minor(dev) >= npty) 92 return (ENXIO); 93 tp = &pt_tty[minor(dev)]; 94 if ((tp->t_state & TS_ISOPEN) == 0) { 95 tp->t_state |= TS_WOPEN; 96 ttychars(tp); /* Set up default chars */ 97 tp->t_iflag = TTYDEF_IFLAG; 98 tp->t_oflag = TTYDEF_OFLAG; 99 tp->t_lflag = TTYDEF_LFLAG; 100 tp->t_cflag = TTYDEF_CFLAG; 101 tp->t_ispeed = tp->t_ospeed = TTYDEF_SPEED; 102 ttsetwater(tp); /* would be done in xxparam() */ 103 } else if (tp->t_state&TS_XCLUDE && p->p_ucred->cr_uid != 0) 104 return (EBUSY); 105 if (tp->t_oproc) /* Ctrlr still around. */ 106 tp->t_state |= TS_CARR_ON; 107 while ((tp->t_state & TS_CARR_ON) == 0) { 108 tp->t_state |= TS_WOPEN; 109 if (flag&FNONBLOCK) 110 break; 111 if (error = ttysleep(tp, (caddr_t)&tp->t_rawq, TTIPRI | PCATCH, 112 ttopen, 0)) 113 return (error); 114 } 115 error = (*linesw[tp->t_line].l_open)(dev, tp); 116 ptcwakeup(tp, FREAD|FWRITE); 117 return (error); 118 } 119 120 ptsclose(dev, flag, mode, p) 121 dev_t dev; 122 int flag, mode; 123 struct proc *p; 124 { 125 register struct tty *tp; 126 int err; 127 128 tp = &pt_tty[minor(dev)]; 129 err = (*linesw[tp->t_line].l_close)(tp, flag); 130 err |= ttyclose(tp); 131 ptcwakeup(tp, FREAD|FWRITE); 132 return (err); 133 } 134 135 ptsread(dev, uio, flag) 136 dev_t dev; 137 struct uio *uio; 138 int flag; 139 { 140 struct proc *p = curproc; 141 register struct tty *tp = &pt_tty[minor(dev)]; 142 register struct pt_ioctl *pti = &pt_ioctl[minor(dev)]; 143 int error = 0; 144 145 again: 146 if (pti->pt_flags & PF_REMOTE) { 147 while (isbackground(p, tp)) { 148 if ((p->p_sigignore & sigmask(SIGTTIN)) || 149 (p->p_sigmask & sigmask(SIGTTIN)) || 150 p->p_pgrp->pg_jobc == 0 || 151 p->p_flag & P_PPWAIT) 152 return (EIO); 153 pgsignal(p->p_pgrp, SIGTTIN, 1); 154 if (error = ttysleep(tp, (caddr_t)&lbolt, 155 TTIPRI | PCATCH, ttybg, 0)) 156 return (error); 157 } 158 if (tp->t_canq.c_cc == 0) { 159 if (flag & IO_NDELAY) 160 return (EWOULDBLOCK); 161 if (error = ttysleep(tp, (caddr_t)&tp->t_canq, 162 TTIPRI | PCATCH, ttyin, 0)) 163 return (error); 164 goto again; 165 } 166 while (tp->t_canq.c_cc > 1 && uio->uio_resid > 0) 167 if (ureadc(getc(&tp->t_canq), uio) < 0) { 168 error = EFAULT; 169 break; 170 } 171 if (tp->t_canq.c_cc == 1) 172 (void) getc(&tp->t_canq); 173 if (tp->t_canq.c_cc) 174 return (error); 175 } else 176 if (tp->t_oproc) 177 error = (*linesw[tp->t_line].l_read)(tp, uio, flag); 178 ptcwakeup(tp, FWRITE); 179 return (error); 180 } 181 182 /* 183 * Write to pseudo-tty. 184 * Wakeups of controlling tty will happen 185 * indirectly, when tty driver calls ptsstart. 186 */ 187 ptswrite(dev, uio, flag) 188 dev_t dev; 189 struct uio *uio; 190 int flag; 191 { 192 register struct tty *tp; 193 194 tp = &pt_tty[minor(dev)]; 195 if (tp->t_oproc == 0) 196 return (EIO); 197 return ((*linesw[tp->t_line].l_write)(tp, uio, flag)); 198 } 199 200 /* 201 * Start output on pseudo-tty. 202 * Wake up process selecting or sleeping for input from controlling tty. 203 */ 204 void 205 ptsstart(tp) 206 struct tty *tp; 207 { 208 register struct pt_ioctl *pti = &pt_ioctl[minor(tp->t_dev)]; 209 210 if (tp->t_state & TS_TTSTOP) 211 return; 212 if (pti->pt_flags & PF_STOPPED) { 213 pti->pt_flags &= ~PF_STOPPED; 214 pti->pt_send = TIOCPKT_START; 215 } 216 ptcwakeup(tp, FREAD); 217 } 218 219 ptcwakeup(tp, flag) 220 struct tty *tp; 221 int flag; 222 { 223 struct pt_ioctl *pti = &pt_ioctl[minor(tp->t_dev)]; 224 225 if (flag & FREAD) { 226 selwakeup(&pti->pt_selr); 227 wakeup((caddr_t)&tp->t_outq.c_cf); 228 } 229 if (flag & FWRITE) { 230 selwakeup(&pti->pt_selw); 231 wakeup((caddr_t)&tp->t_rawq.c_cf); 232 } 233 } 234 235 /*ARGSUSED*/ 236 #ifdef __STDC__ 237 ptcopen(dev_t dev, int flag, int devtype, struct proc *p) 238 #else 239 ptcopen(dev, flag, devtype, p) 240 dev_t dev; 241 int flag, devtype; 242 struct proc *p; 243 #endif 244 { 245 register struct tty *tp; 246 struct pt_ioctl *pti; 247 248 if (minor(dev) >= npty) 249 return (ENXIO); 250 tp = &pt_tty[minor(dev)]; 251 if (tp->t_oproc) 252 return (EIO); 253 tp->t_oproc = ptsstart; 254 #ifdef sun4c 255 tp->t_stop = ptsstop; 256 #endif 257 (void)(*linesw[tp->t_line].l_modem)(tp, 1); 258 tp->t_lflag &= ~EXTPROC; 259 pti = &pt_ioctl[minor(dev)]; 260 pti->pt_flags = 0; 261 pti->pt_send = 0; 262 pti->pt_ucntl = 0; 263 return (0); 264 } 265 266 ptcclose(dev) 267 dev_t dev; 268 { 269 register struct tty *tp; 270 271 tp = &pt_tty[minor(dev)]; 272 (void)(*linesw[tp->t_line].l_modem)(tp, 0); 273 tp->t_state &= ~TS_CARR_ON; 274 tp->t_oproc = 0; /* mark closed */ 275 tp->t_session = 0; 276 return (0); 277 } 278 279 ptcread(dev, uio, flag) 280 dev_t dev; 281 struct uio *uio; 282 int flag; 283 { 284 register struct tty *tp = &pt_tty[minor(dev)]; 285 struct pt_ioctl *pti = &pt_ioctl[minor(dev)]; 286 char buf[BUFSIZ]; 287 int error = 0, cc; 288 289 /* 290 * We want to block until the slave 291 * is open, and there's something to read; 292 * but if we lost the slave or we're NBIO, 293 * then return the appropriate error instead. 294 */ 295 for (;;) { 296 if (tp->t_state&TS_ISOPEN) { 297 if (pti->pt_flags&PF_PKT && pti->pt_send) { 298 error = ureadc((int)pti->pt_send, uio); 299 if (error) 300 return (error); 301 if (pti->pt_send & TIOCPKT_IOCTL) { 302 cc = min(uio->uio_resid, 303 sizeof(tp->t_termios)); 304 uiomove(&tp->t_termios, cc, uio); 305 } 306 pti->pt_send = 0; 307 return (0); 308 } 309 if (pti->pt_flags&PF_UCNTL && pti->pt_ucntl) { 310 error = ureadc((int)pti->pt_ucntl, uio); 311 if (error) 312 return (error); 313 pti->pt_ucntl = 0; 314 return (0); 315 } 316 if (tp->t_outq.c_cc && (tp->t_state&TS_TTSTOP) == 0) 317 break; 318 } 319 if ((tp->t_state&TS_CARR_ON) == 0) 320 return (0); /* EOF */ 321 if (flag & IO_NDELAY) 322 return (EWOULDBLOCK); 323 if (error = tsleep((caddr_t)&tp->t_outq.c_cf, TTIPRI | PCATCH, 324 ttyin, 0)) 325 return (error); 326 } 327 if (pti->pt_flags & (PF_PKT|PF_UCNTL)) 328 error = ureadc(0, uio); 329 while (uio->uio_resid > 0 && error == 0) { 330 cc = q_to_b(&tp->t_outq, buf, min(uio->uio_resid, BUFSIZ)); 331 if (cc <= 0) 332 break; 333 error = uiomove(buf, cc, uio); 334 } 335 if (tp->t_outq.c_cc <= tp->t_lowat) { 336 if (tp->t_state&TS_ASLEEP) { 337 tp->t_state &= ~TS_ASLEEP; 338 wakeup((caddr_t)&tp->t_outq); 339 } 340 selwakeup(&tp->t_wsel); 341 } 342 return (error); 343 } 344 345 void 346 ptsstop(tp, flush) 347 register struct tty *tp; 348 int flush; 349 { 350 struct pt_ioctl *pti = &pt_ioctl[minor(tp->t_dev)]; 351 int flag; 352 353 /* note: FLUSHREAD and FLUSHWRITE already ok */ 354 if (flush == 0) { 355 flush = TIOCPKT_STOP; 356 pti->pt_flags |= PF_STOPPED; 357 } else 358 pti->pt_flags &= ~PF_STOPPED; 359 pti->pt_send |= flush; 360 /* change of perspective */ 361 flag = 0; 362 if (flush & FREAD) 363 flag |= FWRITE; 364 if (flush & FWRITE) 365 flag |= FREAD; 366 ptcwakeup(tp, flag); 367 } 368 369 ptcselect(dev, rw, p) 370 dev_t dev; 371 int rw; 372 struct proc *p; 373 { 374 register struct tty *tp = &pt_tty[minor(dev)]; 375 struct pt_ioctl *pti = &pt_ioctl[minor(dev)]; 376 int s; 377 378 if ((tp->t_state&TS_CARR_ON) == 0) 379 return (1); 380 switch (rw) { 381 382 case FREAD: 383 /* 384 * Need to block timeouts (ttrstart). 385 */ 386 s = spltty(); 387 if ((tp->t_state&TS_ISOPEN) && 388 tp->t_outq.c_cc && (tp->t_state&TS_TTSTOP) == 0) { 389 splx(s); 390 return (1); 391 } 392 splx(s); 393 /* FALLTHROUGH */ 394 395 case 0: /* exceptional */ 396 if ((tp->t_state&TS_ISOPEN) && 397 (pti->pt_flags&PF_PKT && pti->pt_send || 398 pti->pt_flags&PF_UCNTL && pti->pt_ucntl)) 399 return (1); 400 selrecord(p, &pti->pt_selr); 401 break; 402 403 404 case FWRITE: 405 if (tp->t_state&TS_ISOPEN) { 406 if (pti->pt_flags & PF_REMOTE) { 407 if (tp->t_canq.c_cc == 0) 408 return (1); 409 } else { 410 if (tp->t_rawq.c_cc + tp->t_canq.c_cc < TTYHOG-2) 411 return (1); 412 if (tp->t_canq.c_cc == 0 && (tp->t_iflag&ICANON)) 413 return (1); 414 } 415 } 416 selrecord(p, &pti->pt_selw); 417 break; 418 419 } 420 return (0); 421 } 422 423 ptcwrite(dev, uio, flag) 424 dev_t dev; 425 register struct uio *uio; 426 int flag; 427 { 428 register struct tty *tp = &pt_tty[minor(dev)]; 429 register u_char *cp; 430 register int cc = 0; 431 u_char locbuf[BUFSIZ]; 432 int cnt = 0; 433 struct pt_ioctl *pti = &pt_ioctl[minor(dev)]; 434 int error = 0; 435 436 again: 437 if ((tp->t_state&TS_ISOPEN) == 0) 438 goto block; 439 if (pti->pt_flags & PF_REMOTE) { 440 if (tp->t_canq.c_cc) 441 goto block; 442 while (uio->uio_resid > 0 && tp->t_canq.c_cc < TTYHOG - 1) { 443 if (cc == 0) { 444 cc = min(uio->uio_resid, BUFSIZ); 445 cc = min(cc, TTYHOG - 1 - tp->t_canq.c_cc); 446 cp = locbuf; 447 error = uiomove((caddr_t)cp, cc, uio); 448 if (error) 449 return (error); 450 /* check again for safety */ 451 if ((tp->t_state&TS_ISOPEN) == 0) 452 return (EIO); 453 } 454 if (cc) 455 (void) b_to_q((char *)cp, cc, &tp->t_canq); 456 cc = 0; 457 } 458 (void) putc(0, &tp->t_canq); 459 ttwakeup(tp); 460 wakeup((caddr_t)&tp->t_canq); 461 return (0); 462 } 463 while (uio->uio_resid > 0) { 464 if (cc == 0) { 465 cc = min(uio->uio_resid, BUFSIZ); 466 cp = locbuf; 467 error = uiomove((caddr_t)cp, cc, uio); 468 if (error) 469 return (error); 470 /* check again for safety */ 471 if ((tp->t_state&TS_ISOPEN) == 0) 472 return (EIO); 473 } 474 while (cc > 0) { 475 if ((tp->t_rawq.c_cc + tp->t_canq.c_cc) >= TTYHOG - 2 && 476 (tp->t_canq.c_cc > 0 || !(tp->t_iflag&ICANON))) { 477 wakeup((caddr_t)&tp->t_rawq); 478 goto block; 479 } 480 (*linesw[tp->t_line].l_rint)(*cp++, tp); 481 cnt++; 482 cc--; 483 } 484 cc = 0; 485 } 486 return (0); 487 block: 488 /* 489 * Come here to wait for slave to open, for space 490 * in outq, or space in rawq. 491 */ 492 if ((tp->t_state&TS_CARR_ON) == 0) 493 return (EIO); 494 if (flag & IO_NDELAY) { 495 /* adjust for data copied in but not written */ 496 uio->uio_resid += cc; 497 if (cnt == 0) 498 return (EWOULDBLOCK); 499 return (0); 500 } 501 if (error = tsleep((caddr_t)&tp->t_rawq.c_cf, TTOPRI | PCATCH, 502 ttyout, 0)) { 503 /* adjust for data copied in but not written */ 504 uio->uio_resid += cc; 505 return (error); 506 } 507 goto again; 508 } 509 510 /*ARGSUSED*/ 511 ptyioctl(dev, cmd, data, flag, p) 512 dev_t dev; 513 u_long cmd; 514 caddr_t data; 515 int flag; 516 struct proc *p; 517 { 518 register struct tty *tp = &pt_tty[minor(dev)]; 519 register struct pt_ioctl *pti = &pt_ioctl[minor(dev)]; 520 register u_char *cc = tp->t_cc; 521 int stop, error; 522 523 /* 524 * IF CONTROLLER STTY THEN MUST FLUSH TO PREVENT A HANG. 525 * ttywflush(tp) will hang if there are characters in the outq. 526 */ 527 if (cmd == TIOCEXT) { 528 /* 529 * When the EXTPROC bit is being toggled, we need 530 * to send an TIOCPKT_IOCTL if the packet driver 531 * is turned on. 532 */ 533 if (*(int *)data) { 534 if (pti->pt_flags & PF_PKT) { 535 pti->pt_send |= TIOCPKT_IOCTL; 536 ptcwakeup(tp, FREAD); 537 } 538 tp->t_lflag |= EXTPROC; 539 } else { 540 if ((tp->t_lflag & EXTPROC) && 541 (pti->pt_flags & PF_PKT)) { 542 pti->pt_send |= TIOCPKT_IOCTL; 543 ptcwakeup(tp, FREAD); 544 } 545 tp->t_lflag &= ~EXTPROC; 546 } 547 return(0); 548 } else 549 if (cdevsw[major(dev)].d_open == ptcopen) 550 switch (cmd) { 551 552 case TIOCGPGRP: 553 /* 554 * We aviod calling ttioctl on the controller since, 555 * in that case, tp must be the controlling terminal. 556 */ 557 *(int *)data = tp->t_pgrp ? tp->t_pgrp->pg_id : 0; 558 return (0); 559 560 case TIOCPKT: 561 if (*(int *)data) { 562 if (pti->pt_flags & PF_UCNTL) 563 return (EINVAL); 564 pti->pt_flags |= PF_PKT; 565 } else 566 pti->pt_flags &= ~PF_PKT; 567 return (0); 568 569 case TIOCUCNTL: 570 if (*(int *)data) { 571 if (pti->pt_flags & PF_PKT) 572 return (EINVAL); 573 pti->pt_flags |= PF_UCNTL; 574 } else 575 pti->pt_flags &= ~PF_UCNTL; 576 return (0); 577 578 case TIOCREMOTE: 579 if (*(int *)data) 580 pti->pt_flags |= PF_REMOTE; 581 else 582 pti->pt_flags &= ~PF_REMOTE; 583 ttyflush(tp, FREAD|FWRITE); 584 return (0); 585 586 #ifdef COMPAT_43 587 case TIOCSETP: 588 case TIOCSETN: 589 #endif 590 case TIOCSETD: 591 case TIOCSETA: 592 case TIOCSETAW: 593 case TIOCSETAF: 594 ndflush(&tp->t_outq, tp->t_outq.c_cc); 595 break; 596 597 case TIOCSIG: 598 if (*(unsigned int *)data >= NSIG) 599 return(EINVAL); 600 if ((tp->t_lflag&NOFLSH) == 0) 601 ttyflush(tp, FREAD|FWRITE); 602 pgsignal(tp->t_pgrp, *(unsigned int *)data, 1); 603 if ((*(unsigned int *)data == SIGINFO) && 604 ((tp->t_lflag&NOKERNINFO) == 0)) 605 ttyinfo(tp); 606 return(0); 607 } 608 error = (*linesw[tp->t_line].l_ioctl)(tp, cmd, data, flag, p); 609 if (error < 0) 610 error = ttioctl(tp, cmd, data, flag); 611 if (error < 0) { 612 if (pti->pt_flags & PF_UCNTL && 613 (cmd & ~0xff) == UIOCCMD(0)) { 614 if (cmd & 0xff) { 615 pti->pt_ucntl = (u_char)cmd; 616 ptcwakeup(tp, FREAD); 617 } 618 return (0); 619 } 620 error = ENOTTY; 621 } 622 /* 623 * If external processing and packet mode send ioctl packet. 624 */ 625 if ((tp->t_lflag&EXTPROC) && (pti->pt_flags & PF_PKT)) { 626 switch(cmd) { 627 case TIOCSETA: 628 case TIOCSETAW: 629 case TIOCSETAF: 630 #ifdef COMPAT_43 631 case TIOCSETP: 632 case TIOCSETN: 633 #endif 634 #if defined(COMPAT_43) || defined(COMPAT_SUNOS) 635 case TIOCSETC: 636 case TIOCSLTC: 637 case TIOCLBIS: 638 case TIOCLBIC: 639 case TIOCLSET: 640 #endif 641 pti->pt_send |= TIOCPKT_IOCTL; 642 ptcwakeup(tp, FREAD); 643 default: 644 break; 645 } 646 } 647 stop = (tp->t_iflag & IXON) && CCEQ(cc[VSTOP], CTRL('s')) 648 && CCEQ(cc[VSTART], CTRL('q')); 649 if (pti->pt_flags & PF_NOSTOP) { 650 if (stop) { 651 pti->pt_send &= ~TIOCPKT_NOSTOP; 652 pti->pt_send |= TIOCPKT_DOSTOP; 653 pti->pt_flags &= ~PF_NOSTOP; 654 ptcwakeup(tp, FREAD); 655 } 656 } else { 657 if (!stop) { 658 pti->pt_send &= ~TIOCPKT_DOSTOP; 659 pti->pt_send |= TIOCPKT_NOSTOP; 660 pti->pt_flags |= PF_NOSTOP; 661 ptcwakeup(tp, FREAD); 662 } 663 } 664 return (error); 665 } 666