1 /*- 2 * Copyright (c) 2008 Ed Schouten <ed@FreeBSD.org> 3 * All rights reserved. 4 * 5 * Portions of this software were developed under sponsorship from Snow 6 * B.V., the Netherlands. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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 30 #include <sys/cdefs.h> 31 __FBSDID("$FreeBSD$"); 32 33 #include <sys/param.h> 34 #include <sys/fcntl.h> 35 #include <sys/filio.h> 36 #include <sys/kernel.h> 37 #include <sys/signal.h> 38 #include <sys/sysctl.h> 39 #include <sys/systm.h> 40 #include <sys/tty.h> 41 #include <sys/ttycom.h> 42 #include <sys/ttydefaults.h> 43 #include <sys/uio.h> 44 #include <sys/vnode.h> 45 46 /* 47 * Standard TTYDISC `termios' line discipline. 48 */ 49 50 /* Statistics. */ 51 static long tty_nin = 0; 52 SYSCTL_LONG(_kern, OID_AUTO, tty_nin, CTLFLAG_RD, 53 &tty_nin, 0, "Total amount of bytes received"); 54 static long tty_nout = 0; 55 SYSCTL_LONG(_kern, OID_AUTO, tty_nout, CTLFLAG_RD, 56 &tty_nout, 0, "Total amount of bytes transmitted"); 57 58 /* termios comparison macro's. */ 59 #define CMP_CC(v,c) (tp->t_termios.c_cc[v] != _POSIX_VDISABLE && \ 60 tp->t_termios.c_cc[v] == (c)) 61 #define CMP_FLAG(field,opt) (tp->t_termios.c_ ## field ## flag & (opt)) 62 63 /* Characters that cannot be modified through c_cc. */ 64 #define CTAB '\t' 65 #define CNL '\n' 66 #define CCR '\r' 67 68 /* Character is a control character. */ 69 #define CTL_VALID(c) ((c) == 0x7f || (unsigned char)(c) < 0x20) 70 /* Control character should be processed on echo. */ 71 #define CTL_ECHO(c,q) (!(q) && ((c) == CERASE2 || (c) == CTAB || \ 72 (c) == CNL || (c) == CCR)) 73 /* Control character should be printed using ^X notation. */ 74 #define CTL_PRINT(c,q) ((c) == 0x7f || ((unsigned char)(c) < 0x20 && \ 75 ((q) || ((c) != CTAB && (c) != CNL)))) 76 /* Character is whitespace. */ 77 #define CTL_WHITE(c) ((c) == ' ' || (c) == CTAB) 78 /* Character is alphanumeric. */ 79 #define CTL_ALNUM(c) (((c) >= '0' && (c) <= '9') || \ 80 ((c) >= 'a' && (c) <= 'z') || ((c) >= 'A' && (c) <= 'Z')) 81 82 #define TTY_STACKBUF 256 83 84 void 85 ttydisc_open(struct tty *tp) 86 { 87 ttydisc_optimize(tp); 88 } 89 90 void 91 ttydisc_close(struct tty *tp) 92 { 93 94 /* Clean up our flags when leaving the discipline. */ 95 tp->t_flags &= ~(TF_STOPPED|TF_HIWAT|TF_ZOMBIE); 96 97 /* POSIX states we should flush when close() is called. */ 98 ttyinq_flush(&tp->t_inq); 99 ttyoutq_flush(&tp->t_outq); 100 101 if (!tty_gone(tp)) { 102 ttydevsw_inwakeup(tp); 103 ttydevsw_outwakeup(tp); 104 } 105 106 if (ttyhook_hashook(tp, close)) 107 ttyhook_close(tp); 108 } 109 110 static int 111 ttydisc_read_canonical(struct tty *tp, struct uio *uio, int ioflag) 112 { 113 char breakc[4] = { CNL }; /* enough to hold \n, VEOF and VEOL. */ 114 int error; 115 size_t clen, flen = 0, n = 1; 116 unsigned char lastc = _POSIX_VDISABLE; 117 118 #define BREAK_ADD(c) do { \ 119 if (tp->t_termios.c_cc[c] != _POSIX_VDISABLE) \ 120 breakc[n++] = tp->t_termios.c_cc[c]; \ 121 } while (0) 122 /* Determine which characters we should trigger on. */ 123 BREAK_ADD(VEOF); 124 BREAK_ADD(VEOL); 125 #undef BREAK_ADD 126 breakc[n] = '\0'; 127 128 do { 129 /* 130 * Quite a tricky case: unlike the old TTY 131 * implementation, this implementation copies data back 132 * to userspace in large chunks. Unfortunately, we can't 133 * calculate the line length on beforehand if it crosses 134 * ttyinq_block boundaries, because multiple reads could 135 * then make this code read beyond the newline. 136 * 137 * This is why we limit the read to: 138 * - The size the user has requested 139 * - The blocksize (done in tty_inq.c) 140 * - The amount of bytes until the newline 141 * 142 * This causes the line length to be recalculated after 143 * each block has been copied to userspace. This will 144 * cause the TTY layer to return data in chunks using 145 * the blocksize (except the first and last blocks). 146 */ 147 clen = ttyinq_findchar(&tp->t_inq, breakc, uio->uio_resid, 148 &lastc); 149 150 /* No more data. */ 151 if (clen == 0) { 152 if (ioflag & IO_NDELAY) 153 return (EWOULDBLOCK); 154 else if (tp->t_flags & TF_ZOMBIE) 155 return (0); 156 157 error = tty_wait(tp, &tp->t_inwait); 158 if (error) 159 return (error); 160 continue; 161 } 162 163 /* Don't send the EOF char back to userspace. */ 164 if (CMP_CC(VEOF, lastc)) 165 flen = 1; 166 167 MPASS(flen <= clen); 168 169 /* Read and throw away the EOF character. */ 170 error = ttyinq_read_uio(&tp->t_inq, tp, uio, clen, flen); 171 if (error) 172 return (error); 173 174 } while (uio->uio_resid > 0 && lastc == _POSIX_VDISABLE); 175 176 return (0); 177 } 178 179 static int 180 ttydisc_read_raw_no_timer(struct tty *tp, struct uio *uio, int ioflag) 181 { 182 size_t vmin = tp->t_termios.c_cc[VMIN]; 183 int oresid = uio->uio_resid; 184 int error; 185 186 MPASS(tp->t_termios.c_cc[VTIME] == 0); 187 188 /* 189 * This routine implements the easy cases of read()s while in 190 * non-canonical mode, namely case B and D, where we don't have 191 * any timers at all. 192 */ 193 194 for (;;) { 195 error = ttyinq_read_uio(&tp->t_inq, tp, uio, 196 uio->uio_resid, 0); 197 if (error) 198 return (error); 199 if (uio->uio_resid == 0 || (oresid - uio->uio_resid) >= vmin) 200 return (0); 201 202 /* We have to wait for more. */ 203 if (ioflag & IO_NDELAY) 204 return (EWOULDBLOCK); 205 else if (tp->t_flags & TF_ZOMBIE) 206 return (0); 207 208 error = tty_wait(tp, &tp->t_inwait); 209 if (error) 210 return (error); 211 } 212 } 213 214 static int 215 ttydisc_read_raw_read_timer(struct tty *tp, struct uio *uio, int ioflag, 216 int oresid) 217 { 218 size_t vmin = MAX(tp->t_termios.c_cc[VMIN], 1); 219 unsigned int vtime = tp->t_termios.c_cc[VTIME]; 220 struct timeval end, now, left; 221 int error, hz; 222 223 MPASS(tp->t_termios.c_cc[VTIME] != 0); 224 225 /* Determine when the read should be expired. */ 226 end.tv_sec = vtime / 10; 227 end.tv_usec = (vtime % 10) * 100000; 228 getmicrotime(&now); 229 timevaladd(&end, &now); 230 231 for (;;) { 232 error = ttyinq_read_uio(&tp->t_inq, tp, uio, 233 uio->uio_resid, 0); 234 if (error) 235 return (error); 236 if (uio->uio_resid == 0 || (oresid - uio->uio_resid) >= vmin) 237 return (0); 238 239 /* Calculate how long we should wait. */ 240 getmicrotime(&now); 241 if (timevalcmp(&now, &end, >)) 242 return (0); 243 left = end; 244 timevalsub(&left, &now); 245 hz = tvtohz(&left); 246 247 /* 248 * We have to wait for more. If the timer expires, we 249 * should return a 0-byte read. 250 */ 251 if (ioflag & IO_NDELAY) 252 return (EWOULDBLOCK); 253 else if (tp->t_flags & TF_ZOMBIE) 254 return (0); 255 256 error = tty_timedwait(tp, &tp->t_inwait, hz); 257 if (error) 258 return (error == EWOULDBLOCK ? 0 : error); 259 } 260 261 return (0); 262 } 263 264 static int 265 ttydisc_read_raw_interbyte_timer(struct tty *tp, struct uio *uio, int ioflag) 266 { 267 size_t vmin = tp->t_termios.c_cc[VMIN]; 268 int oresid = uio->uio_resid; 269 int error; 270 271 MPASS(tp->t_termios.c_cc[VMIN] != 0); 272 MPASS(tp->t_termios.c_cc[VTIME] != 0); 273 274 /* 275 * When using the interbyte timer, the timer should be started 276 * after the first byte has been received. We just call into the 277 * generic read timer code after we've received the first byte. 278 */ 279 280 for (;;) { 281 error = ttyinq_read_uio(&tp->t_inq, tp, uio, 282 uio->uio_resid, 0); 283 if (error) 284 return (error); 285 if (uio->uio_resid == 0 || (oresid - uio->uio_resid) >= vmin) 286 return (0); 287 288 /* 289 * Not enough data, but we did receive some, which means 290 * we'll now start using the interbyte timer. 291 */ 292 if (oresid != uio->uio_resid) 293 break; 294 295 /* We have to wait for more. */ 296 if (ioflag & IO_NDELAY) 297 return (EWOULDBLOCK); 298 else if (tp->t_flags & TF_ZOMBIE) 299 return (0); 300 301 error = tty_wait(tp, &tp->t_inwait); 302 if (error) 303 return (error); 304 } 305 306 return ttydisc_read_raw_read_timer(tp, uio, ioflag, oresid); 307 } 308 309 int 310 ttydisc_read(struct tty *tp, struct uio *uio, int ioflag) 311 { 312 int error; 313 314 tty_lock_assert(tp, MA_OWNED); 315 316 if (uio->uio_resid == 0) 317 return (0); 318 319 if (CMP_FLAG(l, ICANON)) 320 error = ttydisc_read_canonical(tp, uio, ioflag); 321 else if (tp->t_termios.c_cc[VTIME] == 0) 322 error = ttydisc_read_raw_no_timer(tp, uio, ioflag); 323 else if (tp->t_termios.c_cc[VMIN] == 0) 324 error = ttydisc_read_raw_read_timer(tp, uio, ioflag, 325 uio->uio_resid); 326 else 327 error = ttydisc_read_raw_interbyte_timer(tp, uio, ioflag); 328 329 if (ttyinq_bytesleft(&tp->t_inq) >= tp->t_inlow || 330 ttyinq_bytescanonicalized(&tp->t_inq) == 0) { 331 /* Unset the input watermark when we've got enough space. */ 332 tty_hiwat_in_unblock(tp); 333 } 334 335 return (error); 336 } 337 338 static __inline unsigned int 339 ttydisc_findchar(const char *obstart, unsigned int oblen) 340 { 341 const char *c = obstart; 342 343 while (oblen--) { 344 if (CTL_VALID(*c)) 345 break; 346 c++; 347 } 348 349 return (c - obstart); 350 } 351 352 static int 353 ttydisc_write_oproc(struct tty *tp, char c) 354 { 355 unsigned int scnt, error; 356 357 MPASS(CMP_FLAG(o, OPOST)); 358 MPASS(CTL_VALID(c)); 359 360 #define PRINT_NORMAL() ttyoutq_write_nofrag(&tp->t_outq, &c, 1) 361 switch (c) { 362 case CEOF: 363 /* End-of-text dropping. */ 364 if (CMP_FLAG(o, ONOEOT)) 365 return (0); 366 return PRINT_NORMAL(); 367 368 case CERASE2: 369 /* Handle backspace to fix tab expansion. */ 370 if (PRINT_NORMAL() != 0) 371 return (-1); 372 if (tp->t_column > 0) 373 tp->t_column--; 374 return (0); 375 376 case CTAB: 377 /* Tab expansion. */ 378 scnt = 8 - (tp->t_column & 7); 379 if (CMP_FLAG(o, TAB3)) { 380 error = ttyoutq_write_nofrag(&tp->t_outq, 381 " ", scnt); 382 } else { 383 error = PRINT_NORMAL(); 384 } 385 if (error) 386 return (-1); 387 388 tp->t_column += scnt; 389 MPASS((tp->t_column % 8) == 0); 390 return (0); 391 392 case CNL: 393 /* Newline conversion. */ 394 if (CMP_FLAG(o, ONLCR)) { 395 /* Convert \n to \r\n. */ 396 error = ttyoutq_write_nofrag(&tp->t_outq, "\r\n", 2); 397 } else { 398 error = PRINT_NORMAL(); 399 } 400 if (error) 401 return (-1); 402 403 if (CMP_FLAG(o, ONLCR|ONLRET)) { 404 tp->t_column = tp->t_writepos = 0; 405 ttyinq_reprintpos_set(&tp->t_inq); 406 } 407 return (0); 408 409 case CCR: 410 /* Carriage return to newline conversion. */ 411 if (CMP_FLAG(o, OCRNL)) 412 c = CNL; 413 /* Omit carriage returns on column 0. */ 414 if (CMP_FLAG(o, ONOCR) && tp->t_column == 0) 415 return (0); 416 if (PRINT_NORMAL() != 0) 417 return (-1); 418 419 tp->t_column = tp->t_writepos = 0; 420 ttyinq_reprintpos_set(&tp->t_inq); 421 return (0); 422 } 423 424 /* 425 * Invisible control character. Print it, but don't 426 * increase the column count. 427 */ 428 return PRINT_NORMAL(); 429 #undef PRINT_NORMAL 430 } 431 432 /* 433 * Just like the old TTY implementation, we need to copy data in chunks 434 * into a temporary buffer. One of the reasons why we need to do this, 435 * is because output processing (only TAB3 though) may allow the buffer 436 * to grow eight times. 437 */ 438 int 439 ttydisc_write(struct tty *tp, struct uio *uio, int ioflag) 440 { 441 char ob[TTY_STACKBUF]; 442 char *obstart; 443 int error = 0; 444 unsigned int oblen = 0; 445 446 tty_lock_assert(tp, MA_OWNED); 447 448 if (tp->t_flags & TF_ZOMBIE) 449 return (EIO); 450 451 /* 452 * We don't need to check whether the process is the foreground 453 * process group or if we have a carrier. This is already done 454 * in ttydev_write(). 455 */ 456 457 while (uio->uio_resid > 0) { 458 unsigned int nlen; 459 460 MPASS(oblen == 0); 461 462 /* Step 1: read data. */ 463 464 tty_unlock(tp); 465 466 obstart = ob; 467 nlen = MIN(uio->uio_resid, sizeof ob); 468 error = uiomove(ob, nlen, uio); 469 if (error != 0) 470 break; 471 oblen = nlen; 472 473 tty_lock(tp); 474 if (tty_gone(tp)) { 475 error = ENXIO; 476 break; 477 } 478 479 MPASS(oblen > 0); 480 481 /* Step 2: process data. */ 482 do { 483 unsigned int plen, wlen; 484 485 /* Search for special characters for post processing. */ 486 if (CMP_FLAG(o, OPOST)) { 487 plen = ttydisc_findchar(obstart, oblen); 488 } else { 489 plen = oblen; 490 } 491 492 if (plen == 0) { 493 /* 494 * We're going to process a character 495 * that needs processing 496 */ 497 if (ttydisc_write_oproc(tp, *obstart) == 0) { 498 obstart++; 499 oblen--; 500 501 tp->t_writepos = tp->t_column; 502 ttyinq_reprintpos_set(&tp->t_inq); 503 continue; 504 } 505 } else { 506 /* We're going to write regular data. */ 507 wlen = ttyoutq_write(&tp->t_outq, obstart, plen); 508 obstart += wlen; 509 oblen -= wlen; 510 tp->t_column += wlen; 511 512 tp->t_writepos = tp->t_column; 513 ttyinq_reprintpos_set(&tp->t_inq); 514 515 if (wlen == plen) 516 continue; 517 } 518 519 /* Watermark reached. Try to sleep. */ 520 tp->t_flags |= TF_HIWAT_OUT; 521 522 if (ioflag & IO_NDELAY) { 523 error = EWOULDBLOCK; 524 goto done; 525 } 526 527 /* 528 * The driver may write back the data 529 * synchronously. Be sure to check the high 530 * water mark before going to sleep. 531 */ 532 ttydevsw_outwakeup(tp); 533 if ((tp->t_flags & TF_HIWAT_OUT) == 0) 534 continue; 535 536 error = tty_wait(tp, &tp->t_outwait); 537 if (error) 538 goto done; 539 540 if (tp->t_flags & TF_ZOMBIE) { 541 error = EIO; 542 goto done; 543 } 544 } while (oblen > 0); 545 } 546 547 done: 548 if (!tty_gone(tp)) 549 ttydevsw_outwakeup(tp); 550 551 /* 552 * Add the amount of bytes that we didn't process back to the 553 * uio counters. We need to do this to make sure write() doesn't 554 * count the bytes we didn't store in the queue. 555 */ 556 uio->uio_resid += oblen; 557 return (error); 558 } 559 560 void 561 ttydisc_optimize(struct tty *tp) 562 { 563 tty_lock_assert(tp, MA_OWNED); 564 565 if ((!CMP_FLAG(i, ICRNL|IGNCR|IMAXBEL|INLCR|ISTRIP|IXON) && 566 (!CMP_FLAG(i, BRKINT) || CMP_FLAG(i, IGNBRK)) && 567 (!CMP_FLAG(i, PARMRK) || 568 CMP_FLAG(i, IGNPAR|IGNBRK) == (IGNPAR|IGNBRK)) && 569 !CMP_FLAG(l, ECHO|ICANON|IEXTEN|ISIG|PENDIN)) || 570 ttyhook_hashook(tp, rint_bypass)) { 571 tp->t_flags |= TF_BYPASS; 572 } else { 573 tp->t_flags &= ~TF_BYPASS; 574 } 575 } 576 577 void 578 ttydisc_modem(struct tty *tp, int open) 579 { 580 581 tty_lock_assert(tp, MA_OWNED); 582 583 if (open) 584 cv_broadcast(&tp->t_dcdwait); 585 586 /* 587 * Ignore modem status lines when CLOCAL is turned on, but don't 588 * enter the zombie state when the TTY isn't opened, because 589 * that would cause the TTY to be in zombie state after being 590 * opened. 591 */ 592 if (!tty_opened(tp) || CMP_FLAG(c, CLOCAL)) 593 return; 594 595 if (open == 0) { 596 /* 597 * Lost carrier. 598 */ 599 tp->t_flags |= TF_ZOMBIE; 600 601 tty_signal_sessleader(tp, SIGHUP); 602 tty_flush(tp, FREAD|FWRITE); 603 } else { 604 /* 605 * Carrier is back again. 606 */ 607 608 /* XXX: what should we do here? */ 609 } 610 } 611 612 static int 613 ttydisc_echo_force(struct tty *tp, char c, int quote) 614 { 615 616 if (CMP_FLAG(o, OPOST) && CTL_ECHO(c, quote)) { 617 /* 618 * Only perform postprocessing when OPOST is turned on 619 * and the character is an unquoted BS/TB/NL/CR. 620 */ 621 return ttydisc_write_oproc(tp, c); 622 } else if (CMP_FLAG(l, ECHOCTL) && CTL_PRINT(c, quote)) { 623 /* 624 * Only use ^X notation when ECHOCTL is turned on and 625 * we've got an quoted control character. 626 */ 627 char ob[2] = { '^', '?' }; 628 629 /* Print ^X notation. */ 630 if (c != 0x7f) 631 ob[1] = c + 'A' - 1; 632 633 tp->t_column += 2; 634 return ttyoutq_write_nofrag(&tp->t_outq, ob, 2); 635 } else { 636 /* Can just be printed. */ 637 tp->t_column++; 638 return ttyoutq_write_nofrag(&tp->t_outq, &c, 1); 639 } 640 } 641 642 static int 643 ttydisc_echo(struct tty *tp, char c, int quote) 644 { 645 646 /* 647 * Only echo characters when ECHO is turned on, or ECHONL when 648 * the character is an unquoted newline. 649 */ 650 if (!CMP_FLAG(l, ECHO) && 651 (!CMP_FLAG(l, ECHONL) || c != CNL || quote)) 652 return (0); 653 654 return ttydisc_echo_force(tp, c, quote); 655 } 656 657 658 static void 659 ttydisc_reprint_char(void *d, char c, int quote) 660 { 661 struct tty *tp = d; 662 663 ttydisc_echo(tp, c, quote); 664 } 665 666 static void 667 ttydisc_reprint(struct tty *tp) 668 { 669 cc_t c; 670 671 /* Print ^R\n, followed by the line. */ 672 c = tp->t_termios.c_cc[VREPRINT]; 673 if (c != _POSIX_VDISABLE) 674 ttydisc_echo(tp, c, 0); 675 ttydisc_echo(tp, CNL, 0); 676 ttyinq_reprintpos_reset(&tp->t_inq); 677 678 ttyinq_line_iterate_from_linestart(&tp->t_inq, ttydisc_reprint_char, tp); 679 } 680 681 struct ttydisc_recalc_length { 682 struct tty *tp; 683 unsigned int curlen; 684 }; 685 686 static void 687 ttydisc_recalc_charlength(void *d, char c, int quote) 688 { 689 struct ttydisc_recalc_length *data = d; 690 struct tty *tp = data->tp; 691 692 if (CTL_PRINT(c, quote)) { 693 if (CMP_FLAG(l, ECHOCTL)) 694 data->curlen += 2; 695 } else if (c == CTAB) { 696 data->curlen += 8 - (data->curlen & 7); 697 } else { 698 data->curlen++; 699 } 700 } 701 702 static unsigned int 703 ttydisc_recalc_linelength(struct tty *tp) 704 { 705 struct ttydisc_recalc_length data = { tp, tp->t_writepos }; 706 707 ttyinq_line_iterate_from_reprintpos(&tp->t_inq, 708 ttydisc_recalc_charlength, &data); 709 return (data.curlen); 710 } 711 712 static int 713 ttydisc_rubchar(struct tty *tp) 714 { 715 char c; 716 int quote; 717 unsigned int prevpos, tablen; 718 719 if (ttyinq_peekchar(&tp->t_inq, &c, "e) != 0) 720 return (-1); 721 ttyinq_unputchar(&tp->t_inq); 722 723 if (CMP_FLAG(l, ECHO)) { 724 /* 725 * Remove the character from the screen. This is even 726 * safe for characters that span multiple characters 727 * (tabs, quoted, etc). 728 */ 729 if (tp->t_writepos >= tp->t_column) { 730 /* Retype the sentence. */ 731 ttydisc_reprint(tp); 732 } else if (CMP_FLAG(l, ECHOE)) { 733 if (CTL_PRINT(c, quote)) { 734 /* Remove ^X formatted chars. */ 735 if (CMP_FLAG(l, ECHOCTL)) { 736 tp->t_column -= 2; 737 ttyoutq_write_nofrag(&tp->t_outq, 738 "\b\b \b\b", 6); 739 } 740 } else if (c == ' ') { 741 /* Space character needs no rubbing. */ 742 tp->t_column -= 1; 743 ttyoutq_write_nofrag(&tp->t_outq, "\b", 1); 744 } else if (c == CTAB) { 745 /* 746 * Making backspace work with tabs is 747 * quite hard. Recalculate the length of 748 * this character and remove it. 749 * 750 * Because terminal settings could be 751 * changed while the line is being 752 * inserted, the calculations don't have 753 * to be correct. Make sure we keep the 754 * tab length within proper bounds. 755 */ 756 prevpos = ttydisc_recalc_linelength(tp); 757 if (prevpos >= tp->t_column) 758 tablen = 1; 759 else 760 tablen = tp->t_column - prevpos; 761 if (tablen > 8) 762 tablen = 8; 763 764 tp->t_column = prevpos; 765 ttyoutq_write_nofrag(&tp->t_outq, 766 "\b\b\b\b\b\b\b\b", tablen); 767 return (0); 768 } else { 769 /* 770 * Remove a regular character by 771 * punching a space over it. 772 */ 773 tp->t_column -= 1; 774 ttyoutq_write_nofrag(&tp->t_outq, "\b \b", 3); 775 } 776 } else { 777 /* Don't print spaces. */ 778 ttydisc_echo(tp, tp->t_termios.c_cc[VERASE], 0); 779 } 780 } 781 782 return (0); 783 } 784 785 static void 786 ttydisc_rubword(struct tty *tp) 787 { 788 char c; 789 int quote, alnum; 790 791 /* Strip whitespace first. */ 792 for (;;) { 793 if (ttyinq_peekchar(&tp->t_inq, &c, "e) != 0) 794 return; 795 if (!CTL_WHITE(c)) 796 break; 797 ttydisc_rubchar(tp); 798 } 799 800 /* 801 * Record whether the last character from the previous iteration 802 * was alphanumeric or not. We need this to implement ALTWERASE. 803 */ 804 alnum = CTL_ALNUM(c); 805 for (;;) { 806 ttydisc_rubchar(tp); 807 808 if (ttyinq_peekchar(&tp->t_inq, &c, "e) != 0) 809 return; 810 if (CTL_WHITE(c)) 811 return; 812 if (CMP_FLAG(l, ALTWERASE) && CTL_ALNUM(c) != alnum) 813 return; 814 } 815 } 816 817 int 818 ttydisc_rint(struct tty *tp, char c, int flags) 819 { 820 int signal, quote = 0; 821 char ob[3] = { 0xff, 0x00 }; 822 size_t ol; 823 824 tty_lock_assert(tp, MA_OWNED); 825 826 atomic_add_long(&tty_nin, 1); 827 828 if (ttyhook_hashook(tp, rint)) 829 return ttyhook_rint(tp, c, flags); 830 831 if (tp->t_flags & TF_BYPASS) 832 goto processed; 833 834 if (flags) { 835 if (flags & TRE_BREAK) { 836 if (CMP_FLAG(i, IGNBRK)) { 837 /* Ignore break characters. */ 838 return (0); 839 } else if (CMP_FLAG(i, BRKINT)) { 840 /* Generate SIGINT on break. */ 841 tty_flush(tp, FREAD|FWRITE); 842 tty_signal_pgrp(tp, SIGINT); 843 return (0); 844 } else { 845 /* Just print it. */ 846 goto parmrk; 847 } 848 } else if (flags & TRE_FRAMING || 849 (flags & TRE_PARITY && CMP_FLAG(i, INPCK))) { 850 if (CMP_FLAG(i, IGNPAR)) { 851 /* Ignore bad characters. */ 852 return (0); 853 } else { 854 /* Just print it. */ 855 goto parmrk; 856 } 857 } 858 } 859 860 /* Allow any character to perform a wakeup. */ 861 if (CMP_FLAG(i, IXANY)) 862 tp->t_flags &= ~TF_STOPPED; 863 864 /* Remove the top bit. */ 865 if (CMP_FLAG(i, ISTRIP)) 866 c &= ~0x80; 867 868 /* Skip input processing when we want to print it literally. */ 869 if (tp->t_flags & TF_LITERAL) { 870 tp->t_flags &= ~TF_LITERAL; 871 quote = 1; 872 goto processed; 873 } 874 875 /* Special control characters that are implementation dependent. */ 876 if (CMP_FLAG(l, IEXTEN)) { 877 /* Accept the next character as literal. */ 878 if (CMP_CC(VLNEXT, c)) { 879 if (CMP_FLAG(l, ECHO)) { 880 if (CMP_FLAG(l, ECHOE)) 881 ttyoutq_write_nofrag(&tp->t_outq, "^\b", 2); 882 else 883 ttydisc_echo(tp, c, 0); 884 } 885 tp->t_flags |= TF_LITERAL; 886 return (0); 887 } 888 } 889 890 /* 891 * Handle signal processing. 892 */ 893 if (CMP_FLAG(l, ISIG)) { 894 if (CMP_FLAG(l, ICANON|IEXTEN) == (ICANON|IEXTEN)) { 895 if (CMP_CC(VSTATUS, c)) { 896 tty_signal_pgrp(tp, SIGINFO); 897 return (0); 898 } 899 } 900 901 /* 902 * When compared to the old implementation, this 903 * implementation also flushes the output queue. POSIX 904 * is really brief about this, but does makes us assume 905 * we have to do so. 906 */ 907 signal = 0; 908 if (CMP_CC(VINTR, c)) { 909 signal = SIGINT; 910 } else if (CMP_CC(VQUIT, c)) { 911 signal = SIGQUIT; 912 } else if (CMP_CC(VSUSP, c)) { 913 signal = SIGTSTP; 914 } 915 916 if (signal != 0) { 917 /* 918 * Echo the character before signalling the 919 * processes. 920 */ 921 if (!CMP_FLAG(l, NOFLSH)) 922 tty_flush(tp, FREAD|FWRITE); 923 ttydisc_echo(tp, c, 0); 924 tty_signal_pgrp(tp, signal); 925 return (0); 926 } 927 } 928 929 /* 930 * Handle start/stop characters. 931 */ 932 if (CMP_FLAG(i, IXON)) { 933 if (CMP_CC(VSTOP, c)) { 934 /* Stop it if we aren't stopped yet. */ 935 if ((tp->t_flags & TF_STOPPED) == 0) { 936 tp->t_flags |= TF_STOPPED; 937 return (0); 938 } 939 /* 940 * Fallthrough: 941 * When VSTART == VSTOP, we should make this key 942 * toggle it. 943 */ 944 if (!CMP_CC(VSTART, c)) 945 return (0); 946 } 947 if (CMP_CC(VSTART, c)) { 948 tp->t_flags &= ~TF_STOPPED; 949 return (0); 950 } 951 } 952 953 /* Conversion of CR and NL. */ 954 switch (c) { 955 case CCR: 956 if (CMP_FLAG(i, IGNCR)) 957 return (0); 958 if (CMP_FLAG(i, ICRNL)) 959 c = CNL; 960 break; 961 case CNL: 962 if (CMP_FLAG(i, INLCR)) 963 c = CCR; 964 break; 965 } 966 967 /* Canonical line editing. */ 968 if (CMP_FLAG(l, ICANON)) { 969 if (CMP_CC(VERASE, c) || CMP_CC(VERASE2, c)) { 970 ttydisc_rubchar(tp); 971 return (0); 972 } else if (CMP_CC(VKILL, c)) { 973 while (ttydisc_rubchar(tp) == 0); 974 return (0); 975 } else if (CMP_FLAG(l, IEXTEN)) { 976 if (CMP_CC(VWERASE, c)) { 977 ttydisc_rubword(tp); 978 return (0); 979 } else if (CMP_CC(VREPRINT, c)) { 980 ttydisc_reprint(tp); 981 return (0); 982 } 983 } 984 } 985 986 processed: 987 if (CMP_FLAG(i, PARMRK) && (unsigned char)c == 0xff) { 988 /* Print 0xff 0xff. */ 989 ob[1] = 0xff; 990 ol = 2; 991 quote = 1; 992 } else { 993 ob[0] = c; 994 ol = 1; 995 } 996 997 goto print; 998 999 parmrk: 1000 if (CMP_FLAG(i, PARMRK)) { 1001 /* Prepend 0xff 0x00 0x.. */ 1002 ob[2] = c; 1003 ol = 3; 1004 quote = 1; 1005 } else { 1006 ob[0] = c; 1007 ol = 1; 1008 } 1009 1010 print: 1011 /* See if we can store this on the input queue. */ 1012 if (ttyinq_write_nofrag(&tp->t_inq, ob, ol, quote) != 0) { 1013 if (CMP_FLAG(i, IMAXBEL)) 1014 ttyoutq_write_nofrag(&tp->t_outq, "\a", 1); 1015 1016 /* 1017 * Prevent a deadlock here. It may be possible that a 1018 * user has entered so much data, there is no data 1019 * available to read(), but the buffers are full anyway. 1020 * 1021 * Only enter the high watermark if the device driver 1022 * can actually transmit something. 1023 */ 1024 if (ttyinq_bytescanonicalized(&tp->t_inq) == 0) 1025 return (0); 1026 1027 tty_hiwat_in_block(tp); 1028 return (-1); 1029 } 1030 1031 /* 1032 * In raw mode, we canonicalize after receiving a single 1033 * character. Otherwise, we canonicalize when we receive a 1034 * newline, VEOL or VEOF, but only when it isn't quoted. 1035 */ 1036 if (!CMP_FLAG(l, ICANON) || 1037 (!quote && (c == CNL || CMP_CC(VEOL, c) || CMP_CC(VEOF, c)))) { 1038 ttyinq_canonicalize(&tp->t_inq); 1039 } 1040 1041 ttydisc_echo(tp, c, quote); 1042 1043 return (0); 1044 } 1045 1046 size_t 1047 ttydisc_rint_bypass(struct tty *tp, const void *buf, size_t len) 1048 { 1049 size_t ret; 1050 1051 tty_lock_assert(tp, MA_OWNED); 1052 1053 MPASS(tp->t_flags & TF_BYPASS); 1054 1055 atomic_add_long(&tty_nin, len); 1056 1057 if (ttyhook_hashook(tp, rint_bypass)) 1058 return ttyhook_rint_bypass(tp, buf, len); 1059 1060 ret = ttyinq_write(&tp->t_inq, buf, len, 0); 1061 ttyinq_canonicalize(&tp->t_inq); 1062 1063 return (ret); 1064 } 1065 1066 void 1067 ttydisc_rint_done(struct tty *tp) 1068 { 1069 1070 tty_lock_assert(tp, MA_OWNED); 1071 1072 if (ttyhook_hashook(tp, rint_done)) 1073 ttyhook_rint_done(tp); 1074 1075 /* Wake up readers. */ 1076 tty_wakeup(tp, FREAD); 1077 /* Wake up driver for echo. */ 1078 ttydevsw_outwakeup(tp); 1079 } 1080 1081 size_t 1082 ttydisc_rint_poll(struct tty *tp) 1083 { 1084 size_t l; 1085 1086 tty_lock_assert(tp, MA_OWNED); 1087 1088 if (ttyhook_hashook(tp, rint_poll)) 1089 return ttyhook_rint_poll(tp); 1090 1091 /* 1092 * XXX: Still allow character input when there's no space in the 1093 * buffers, but we haven't entered the high watermark. This is 1094 * to allow backspace characters to be inserted when in 1095 * canonical mode. 1096 */ 1097 l = ttyinq_bytesleft(&tp->t_inq); 1098 if (l == 0 && (tp->t_flags & TF_HIWAT_IN) == 0) 1099 return (1); 1100 1101 return (l); 1102 } 1103 1104 static void 1105 ttydisc_wakeup_watermark(struct tty *tp) 1106 { 1107 size_t c; 1108 1109 c = ttyoutq_bytesleft(&tp->t_outq); 1110 if (tp->t_flags & TF_HIWAT_OUT) { 1111 /* Only allow us to run when we're below the watermark. */ 1112 if (c < tp->t_outlow) 1113 return; 1114 1115 /* Reset the watermark. */ 1116 tp->t_flags &= ~TF_HIWAT_OUT; 1117 } else { 1118 /* Only run when we have data at all. */ 1119 if (c == 0) 1120 return; 1121 } 1122 tty_wakeup(tp, FWRITE); 1123 } 1124 1125 size_t 1126 ttydisc_getc(struct tty *tp, void *buf, size_t len) 1127 { 1128 1129 tty_lock_assert(tp, MA_OWNED); 1130 1131 if (tp->t_flags & TF_STOPPED) 1132 return (0); 1133 1134 if (ttyhook_hashook(tp, getc_inject)) 1135 return ttyhook_getc_inject(tp, buf, len); 1136 1137 len = ttyoutq_read(&tp->t_outq, buf, len); 1138 1139 if (ttyhook_hashook(tp, getc_capture)) 1140 ttyhook_getc_capture(tp, buf, len); 1141 1142 ttydisc_wakeup_watermark(tp); 1143 atomic_add_long(&tty_nout, len); 1144 1145 return (len); 1146 } 1147 1148 int 1149 ttydisc_getc_uio(struct tty *tp, struct uio *uio) 1150 { 1151 int error = 0; 1152 int obytes = uio->uio_resid; 1153 size_t len; 1154 char buf[TTY_STACKBUF]; 1155 1156 tty_lock_assert(tp, MA_OWNED); 1157 1158 if (tp->t_flags & TF_STOPPED) 1159 return (0); 1160 1161 /* 1162 * When a TTY hook is attached, we cannot perform unbuffered 1163 * copying to userspace. Just call ttydisc_getc() and 1164 * temporarily store data in a shadow buffer. 1165 */ 1166 if (ttyhook_hashook(tp, getc_capture) || 1167 ttyhook_hashook(tp, getc_inject)) { 1168 while (uio->uio_resid > 0) { 1169 /* Read to shadow buffer. */ 1170 len = ttydisc_getc(tp, buf, 1171 MIN(uio->uio_resid, sizeof buf)); 1172 if (len == 0) 1173 break; 1174 1175 /* Copy to userspace. */ 1176 tty_unlock(tp); 1177 error = uiomove(buf, len, uio); 1178 tty_lock(tp); 1179 1180 if (error != 0) 1181 break; 1182 } 1183 } else { 1184 error = ttyoutq_read_uio(&tp->t_outq, tp, uio); 1185 1186 ttydisc_wakeup_watermark(tp); 1187 atomic_add_long(&tty_nout, obytes - uio->uio_resid); 1188 } 1189 1190 return (error); 1191 } 1192 1193 size_t 1194 ttydisc_getc_poll(struct tty *tp) 1195 { 1196 1197 tty_lock_assert(tp, MA_OWNED); 1198 1199 if (tp->t_flags & TF_STOPPED) 1200 return (0); 1201 1202 if (ttyhook_hashook(tp, getc_poll)) 1203 return ttyhook_getc_poll(tp); 1204 1205 return ttyoutq_bytesused(&tp->t_outq); 1206 } 1207 1208 /* 1209 * XXX: not really related to the TTYDISC, but we'd better put 1210 * tty_putchar() here, because we need to perform proper output 1211 * processing. 1212 */ 1213 1214 int 1215 tty_putchar(struct tty *tp, char c) 1216 { 1217 tty_lock_assert(tp, MA_OWNED); 1218 1219 if (tty_gone(tp)) 1220 return (-1); 1221 1222 ttydisc_echo_force(tp, c, 0); 1223 tp->t_writepos = tp->t_column; 1224 ttyinq_reprintpos_set(&tp->t_inq); 1225 1226 ttydevsw_outwakeup(tp); 1227 return (0); 1228 } 1229