| 1 | /* |
| 2 | * Copyright (c) 1988 Mark Nudleman |
| 3 | * Copyright (c) 1988 Regents of the University of California. |
| 4 | * All rights reserved. |
| 5 | * |
| 6 | * Redistribution and use in source and binary forms are permitted |
| 7 | * provided that the above copyright notice and this paragraph are |
| 8 | * duplicated in all such forms and that any documentation, |
| 9 | * advertising materials, and other materials related to such |
| 10 | * distribution and use acknowledge that the software was developed |
| 11 | * by Mark Nudleman and the University of California, Berkeley. The |
| 12 | * name of Mark Nudleman or the |
| 13 | * University may not be used to endorse or promote products derived |
| 14 | * from this software without specific prior written permission. |
| 15 | * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR |
| 16 | * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED |
| 17 | * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. |
| 18 | */ |
| 19 | |
| 20 | #ifndef lint |
| 21 | static char sccsid[] = "@(#)screen.c 5.3 (Berkeley) %G%"; |
| 22 | #endif /* not lint */ |
| 23 | |
| 24 | /* |
| 25 | * Routines which deal with the characteristics of the terminal. |
| 26 | * Uses termcap to be as terminal-independent as possible. |
| 27 | * |
| 28 | * {{ Someday this should be rewritten to use curses. }} |
| 29 | */ |
| 30 | |
| 31 | #include "less.h" |
| 32 | #if XENIX |
| 33 | #include <sys/types.h> |
| 34 | #include <sys/ioctl.h> |
| 35 | #endif |
| 36 | |
| 37 | #if TERMIO |
| 38 | #include <termio.h> |
| 39 | #else |
| 40 | #include <sgtty.h> |
| 41 | #endif |
| 42 | |
| 43 | #ifdef TIOCGWINSZ |
| 44 | #include <sys/ioctl.h> |
| 45 | #else |
| 46 | /* |
| 47 | * For the Unix PC (ATT 7300 & 3B1): |
| 48 | * Since WIOCGETD is defined in sys/window.h, we can't use that to decide |
| 49 | * whether to include sys/window.h. Use SIGPHONE from sys/signal.h instead. |
| 50 | */ |
| 51 | #include <sys/signal.h> |
| 52 | #ifdef SIGPHONE |
| 53 | #include <sys/window.h> |
| 54 | #endif |
| 55 | #endif |
| 56 | |
| 57 | /* |
| 58 | * Strings passed to tputs() to do various terminal functions. |
| 59 | */ |
| 60 | static char |
| 61 | *sc_pad, /* Pad string */ |
| 62 | *sc_home, /* Cursor home */ |
| 63 | *sc_addline, /* Add line, scroll down following lines */ |
| 64 | *sc_lower_left, /* Cursor to last line, first column */ |
| 65 | *sc_move, /* General cursor positioning */ |
| 66 | *sc_clear, /* Clear screen */ |
| 67 | *sc_eol_clear, /* Clear to end of line */ |
| 68 | *sc_s_in, /* Enter standout (highlighted) mode */ |
| 69 | *sc_s_out, /* Exit standout mode */ |
| 70 | *sc_u_in, /* Enter underline mode */ |
| 71 | *sc_u_out, /* Exit underline mode */ |
| 72 | *sc_b_in, /* Enter bold mode */ |
| 73 | *sc_b_out, /* Exit bold mode */ |
| 74 | *sc_visual_bell, /* Visual bell (flash screen) sequence */ |
| 75 | *sc_backspace, /* Backspace cursor */ |
| 76 | *sc_init, /* Startup terminal initialization */ |
| 77 | *sc_deinit; /* Exit terminal de-intialization */ |
| 78 | |
| 79 | public int auto_wrap; /* Terminal does \r\n when write past margin */ |
| 80 | public int ignaw; /* Terminal ignores \n immediately after wrap */ |
| 81 | public int erase_char, kill_char; /* The user's erase and line-kill chars */ |
| 82 | public int sc_width, sc_height; /* Height & width of screen */ |
| 83 | public int sc_window = -1; /* window size for forward and backward */ |
| 84 | public int bo_width, be_width; /* Printing width of boldface sequences */ |
| 85 | public int ul_width, ue_width; /* Printing width of underline sequences */ |
| 86 | public int so_width, se_width; /* Printing width of standout sequences */ |
| 87 | |
| 88 | /* |
| 89 | * These two variables are sometimes defined in, |
| 90 | * and needed by, the termcap library. |
| 91 | * It may be necessary on some systems to declare them extern here. |
| 92 | */ |
| 93 | /*extern*/ short ospeed; /* Terminal output baud rate */ |
| 94 | /*extern*/ char PC; /* Pad character */ |
| 95 | |
| 96 | extern int quiet; /* If VERY_QUIET, use visual bell for bell */ |
| 97 | extern int know_dumb; /* Don't complain about a dumb terminal */ |
| 98 | extern int back_scroll; |
| 99 | char *tgetstr(); |
| 100 | char *tgoto(); |
| 101 | |
| 102 | /* |
| 103 | * Change terminal to "raw mode", or restore to "normal" mode. |
| 104 | * "Raw mode" means |
| 105 | * 1. An outstanding read will complete on receipt of a single keystroke. |
| 106 | * 2. Input is not echoed. |
| 107 | * 3. On output, \n is mapped to \r\n. |
| 108 | * 4. \t is NOT expanded into spaces. |
| 109 | * 5. Signal-causing characters such as ctrl-C (interrupt), |
| 110 | * etc. are NOT disabled. |
| 111 | * It doesn't matter whether an input \n is mapped to \r, or vice versa. |
| 112 | */ |
| 113 | public void |
| 114 | raw_mode(on) |
| 115 | int on; |
| 116 | { |
| 117 | #if TERMIO |
| 118 | struct termio s; |
| 119 | static struct termio save_term; |
| 120 | |
| 121 | if (on) |
| 122 | { |
| 123 | /* |
| 124 | * Get terminal modes. |
| 125 | */ |
| 126 | ioctl(2, TCGETA, &s); |
| 127 | |
| 128 | /* |
| 129 | * Save modes and set certain variables dependent on modes. |
| 130 | */ |
| 131 | save_term = s; |
| 132 | ospeed = s.c_cflag & CBAUD; |
| 133 | erase_char = s.c_cc[VERASE]; |
| 134 | kill_char = s.c_cc[VKILL]; |
| 135 | |
| 136 | /* |
| 137 | * Set the modes to the way we want them. |
| 138 | */ |
| 139 | s.c_lflag &= ~(ICANON|ECHO|ECHOE|ECHOK|ECHONL); |
| 140 | s.c_oflag |= (OPOST|ONLCR|TAB3); |
| 141 | s.c_oflag &= ~(OCRNL|ONOCR|ONLRET); |
| 142 | s.c_cc[VMIN] = 1; |
| 143 | s.c_cc[VTIME] = 0; |
| 144 | } else |
| 145 | { |
| 146 | /* |
| 147 | * Restore saved modes. |
| 148 | */ |
| 149 | s = save_term; |
| 150 | } |
| 151 | ioctl(2, TCSETAW, &s); |
| 152 | #else |
| 153 | struct sgttyb s; |
| 154 | static struct sgttyb save_term; |
| 155 | |
| 156 | if (on) |
| 157 | { |
| 158 | /* |
| 159 | * Get terminal modes. |
| 160 | */ |
| 161 | ioctl(2, TIOCGETP, &s); |
| 162 | |
| 163 | /* |
| 164 | * Save modes and set certain variables dependent on modes. |
| 165 | */ |
| 166 | save_term = s; |
| 167 | ospeed = s.sg_ospeed; |
| 168 | erase_char = s.sg_erase; |
| 169 | kill_char = s.sg_kill; |
| 170 | |
| 171 | /* |
| 172 | * Set the modes to the way we want them. |
| 173 | */ |
| 174 | s.sg_flags |= CBREAK; |
| 175 | s.sg_flags &= ~(ECHO|XTABS); |
| 176 | } else |
| 177 | { |
| 178 | /* |
| 179 | * Restore saved modes. |
| 180 | */ |
| 181 | s = save_term; |
| 182 | } |
| 183 | ioctl(2, TIOCSETN, &s); |
| 184 | #endif |
| 185 | } |
| 186 | |
| 187 | static void |
| 188 | cannot(s) |
| 189 | char *s; |
| 190 | { |
| 191 | char message[100]; |
| 192 | |
| 193 | if (know_dumb) |
| 194 | /* |
| 195 | * He knows he has a dumb terminal, so don't tell him. |
| 196 | */ |
| 197 | return; |
| 198 | |
| 199 | (void)sprintf(message, "WARNING: terminal cannot \"%s\"", s); |
| 200 | error(message); |
| 201 | } |
| 202 | |
| 203 | /* |
| 204 | * Get terminal capabilities via termcap. |
| 205 | */ |
| 206 | public void |
| 207 | get_term() |
| 208 | { |
| 209 | char termbuf[2048]; |
| 210 | char *sp; |
| 211 | char *term; |
| 212 | int hard; |
| 213 | #ifdef TIOCGWINSZ |
| 214 | struct winsize w; |
| 215 | #else |
| 216 | #ifdef WIOCGETD |
| 217 | struct uwdata w; |
| 218 | #endif |
| 219 | #endif |
| 220 | static char sbuf[1024]; |
| 221 | |
| 222 | char *getenv(), *strcpy(); |
| 223 | |
| 224 | /* |
| 225 | * Find out what kind of terminal this is. |
| 226 | */ |
| 227 | if ((term = getenv("TERM")) == NULL) |
| 228 | term = "unknown"; |
| 229 | if (tgetent(termbuf, term) <= 0) |
| 230 | (void)strcpy(termbuf, "dumb:co#80:hc:"); |
| 231 | |
| 232 | /* |
| 233 | * Get size of the screen. |
| 234 | */ |
| 235 | #ifdef TIOCGWINSZ |
| 236 | if (ioctl(2, TIOCGWINSZ, &w) == 0 && w.ws_row > 0) |
| 237 | sc_height = w.ws_row; |
| 238 | else |
| 239 | #else |
| 240 | #ifdef WIOCGETD |
| 241 | if (ioctl(2, WIOCGETD, &w) == 0 && w.uw_height > 0) |
| 242 | sc_height = w.uw_height/w.uw_vs; |
| 243 | else |
| 244 | #endif |
| 245 | #endif |
| 246 | sc_height = tgetnum("li"); |
| 247 | hard = (sc_height < 0 || tgetflag("hc")); |
| 248 | if (hard) |
| 249 | { |
| 250 | /* Oh no, this is a hardcopy terminal. */ |
| 251 | sc_height = 24; |
| 252 | } |
| 253 | |
| 254 | #ifdef TIOCGWINSZ |
| 255 | if (ioctl(2, TIOCGWINSZ, &w) == 0 && w.ws_col > 0) |
| 256 | sc_width = w.ws_col; |
| 257 | else |
| 258 | #ifdef WIOCGETD |
| 259 | if (ioctl(2, WIOCGETD, &w) == 0 && w.uw_width > 0) |
| 260 | sc_width = w.uw_width/w.uw_hs; |
| 261 | else |
| 262 | #endif |
| 263 | #endif |
| 264 | sc_width = tgetnum("co"); |
| 265 | if (sc_width < 0) |
| 266 | sc_width = 80; |
| 267 | |
| 268 | auto_wrap = tgetflag("am"); |
| 269 | ignaw = tgetflag("xn"); |
| 270 | |
| 271 | /* |
| 272 | * Assumes termcap variable "sg" is the printing width of |
| 273 | * the standout sequence, the end standout sequence, |
| 274 | * the underline sequence, the end underline sequence, |
| 275 | * the boldface sequence, and the end boldface sequence. |
| 276 | */ |
| 277 | if ((so_width = tgetnum("sg")) < 0) |
| 278 | so_width = 0; |
| 279 | be_width = bo_width = ue_width = ul_width = se_width = so_width; |
| 280 | |
| 281 | /* |
| 282 | * Get various string-valued capabilities. |
| 283 | */ |
| 284 | sp = sbuf; |
| 285 | |
| 286 | sc_pad = tgetstr("pc", &sp); |
| 287 | if (sc_pad != NULL) |
| 288 | PC = *sc_pad; |
| 289 | |
| 290 | sc_init = tgetstr("ti", &sp); |
| 291 | if (sc_init == NULL) |
| 292 | sc_init = ""; |
| 293 | |
| 294 | sc_deinit= tgetstr("te", &sp); |
| 295 | if (sc_deinit == NULL) |
| 296 | sc_deinit = ""; |
| 297 | |
| 298 | sc_eol_clear = tgetstr("ce", &sp); |
| 299 | if (hard || sc_eol_clear == NULL || *sc_eol_clear == '\0') |
| 300 | { |
| 301 | cannot("clear to end of line"); |
| 302 | sc_eol_clear = ""; |
| 303 | } |
| 304 | |
| 305 | sc_clear = tgetstr("cl", &sp); |
| 306 | if (hard || sc_clear == NULL || *sc_clear == '\0') |
| 307 | { |
| 308 | cannot("clear screen"); |
| 309 | sc_clear = "\n\n"; |
| 310 | } |
| 311 | |
| 312 | sc_move = tgetstr("cm", &sp); |
| 313 | if (hard || sc_move == NULL || *sc_move == '\0') |
| 314 | { |
| 315 | /* |
| 316 | * This is not an error here, because we don't |
| 317 | * always need sc_move. |
| 318 | * We need it only if we don't have home or lower-left. |
| 319 | */ |
| 320 | sc_move = ""; |
| 321 | } |
| 322 | |
| 323 | sc_s_in = tgetstr("so", &sp); |
| 324 | if (hard || sc_s_in == NULL) |
| 325 | sc_s_in = ""; |
| 326 | |
| 327 | sc_s_out = tgetstr("se", &sp); |
| 328 | if (hard || sc_s_out == NULL) |
| 329 | sc_s_out = ""; |
| 330 | |
| 331 | sc_u_in = tgetstr("us", &sp); |
| 332 | if (hard || sc_u_in == NULL) |
| 333 | sc_u_in = sc_s_in; |
| 334 | |
| 335 | sc_u_out = tgetstr("ue", &sp); |
| 336 | if (hard || sc_u_out == NULL) |
| 337 | sc_u_out = sc_s_out; |
| 338 | |
| 339 | sc_b_in = tgetstr("md", &sp); |
| 340 | if (hard || sc_b_in == NULL) |
| 341 | { |
| 342 | sc_b_in = sc_s_in; |
| 343 | sc_b_out = sc_s_out; |
| 344 | } else |
| 345 | { |
| 346 | sc_b_out = tgetstr("me", &sp); |
| 347 | if (hard || sc_b_out == NULL) |
| 348 | sc_b_out = ""; |
| 349 | } |
| 350 | |
| 351 | sc_visual_bell = tgetstr("vb", &sp); |
| 352 | if (hard || sc_visual_bell == NULL) |
| 353 | sc_visual_bell = ""; |
| 354 | |
| 355 | sc_home = tgetstr("ho", &sp); |
| 356 | if (hard || sc_home == NULL || *sc_home == '\0') |
| 357 | { |
| 358 | if (*sc_move == '\0') |
| 359 | { |
| 360 | cannot("home cursor"); |
| 361 | /* |
| 362 | * This last resort for sc_home is supposed to |
| 363 | * be an up-arrow suggesting moving to the |
| 364 | * top of the "virtual screen". (The one in |
| 365 | * your imagination as you try to use this on |
| 366 | * a hard copy terminal.) |
| 367 | */ |
| 368 | sc_home = "|\b^"; |
| 369 | } else |
| 370 | { |
| 371 | /* |
| 372 | * No "home" string, |
| 373 | * but we can use "move(0,0)". |
| 374 | */ |
| 375 | (void)strcpy(sp, tgoto(sc_move, 0, 0)); |
| 376 | sc_home = sp; |
| 377 | sp += strlen(sp) + 1; |
| 378 | } |
| 379 | } |
| 380 | |
| 381 | sc_lower_left = tgetstr("ll", &sp); |
| 382 | if (hard || sc_lower_left == NULL || *sc_lower_left == '\0') |
| 383 | { |
| 384 | if (*sc_move == '\0') |
| 385 | { |
| 386 | cannot("move cursor to lower left of screen"); |
| 387 | sc_lower_left = "\r"; |
| 388 | } else |
| 389 | { |
| 390 | /* |
| 391 | * No "lower-left" string, |
| 392 | * but we can use "move(0,last-line)". |
| 393 | */ |
| 394 | (void)strcpy(sp, tgoto(sc_move, 0, sc_height-1)); |
| 395 | sc_lower_left = sp; |
| 396 | sp += strlen(sp) + 1; |
| 397 | } |
| 398 | } |
| 399 | |
| 400 | /* |
| 401 | * To add a line at top of screen and scroll the display down, |
| 402 | * we use "al" (add line) or "sr" (scroll reverse). |
| 403 | */ |
| 404 | if ((sc_addline = tgetstr("al", &sp)) == NULL || |
| 405 | *sc_addline == '\0') |
| 406 | sc_addline = tgetstr("sr", &sp); |
| 407 | |
| 408 | if (hard || sc_addline == NULL || *sc_addline == '\0') |
| 409 | { |
| 410 | cannot("scroll backwards"); |
| 411 | sc_addline = ""; |
| 412 | /* Force repaint on any backward movement */ |
| 413 | back_scroll = 0; |
| 414 | } |
| 415 | |
| 416 | if (tgetflag("bs")) |
| 417 | sc_backspace = "\b"; |
| 418 | else |
| 419 | { |
| 420 | sc_backspace = tgetstr("bc", &sp); |
| 421 | if (sc_backspace == NULL || *sc_backspace == '\0') |
| 422 | sc_backspace = "\b"; |
| 423 | } |
| 424 | } |
| 425 | |
| 426 | |
| 427 | /* |
| 428 | * Below are the functions which perform all the |
| 429 | * terminal-specific screen manipulation. |
| 430 | */ |
| 431 | |
| 432 | |
| 433 | /* |
| 434 | * Initialize terminal |
| 435 | */ |
| 436 | public void |
| 437 | init() |
| 438 | { |
| 439 | tputs(sc_init, sc_height, putchr); |
| 440 | } |
| 441 | |
| 442 | /* |
| 443 | * Deinitialize terminal |
| 444 | */ |
| 445 | public void |
| 446 | deinit() |
| 447 | { |
| 448 | tputs(sc_deinit, sc_height, putchr); |
| 449 | } |
| 450 | |
| 451 | /* |
| 452 | * Home cursor (move to upper left corner of screen). |
| 453 | */ |
| 454 | public void |
| 455 | home() |
| 456 | { |
| 457 | tputs(sc_home, 1, putchr); |
| 458 | } |
| 459 | |
| 460 | /* |
| 461 | * Add a blank line (called with cursor at home). |
| 462 | * Should scroll the display down. |
| 463 | */ |
| 464 | public void |
| 465 | add_line() |
| 466 | { |
| 467 | tputs(sc_addline, sc_height, putchr); |
| 468 | } |
| 469 | |
| 470 | /* |
| 471 | * Move cursor to lower left corner of screen. |
| 472 | */ |
| 473 | public void |
| 474 | lower_left() |
| 475 | { |
| 476 | tputs(sc_lower_left, 1, putchr); |
| 477 | } |
| 478 | |
| 479 | /* |
| 480 | * Ring the terminal bell. |
| 481 | */ |
| 482 | public void |
| 483 | bell() |
| 484 | { |
| 485 | if (quiet == VERY_QUIET) |
| 486 | vbell(); |
| 487 | else |
| 488 | putchr('\7'); |
| 489 | } |
| 490 | |
| 491 | /* |
| 492 | * Output the "visual bell", if there is one. |
| 493 | */ |
| 494 | public void |
| 495 | vbell() |
| 496 | { |
| 497 | if (*sc_visual_bell == '\0') |
| 498 | return; |
| 499 | tputs(sc_visual_bell, sc_height, putchr); |
| 500 | } |
| 501 | |
| 502 | /* |
| 503 | * Clear the screen. |
| 504 | */ |
| 505 | public void |
| 506 | clear() |
| 507 | { |
| 508 | tputs(sc_clear, sc_height, putchr); |
| 509 | } |
| 510 | |
| 511 | /* |
| 512 | * Clear from the cursor to the end of the cursor's line. |
| 513 | * {{ This must not move the cursor. }} |
| 514 | */ |
| 515 | public void |
| 516 | clear_eol() |
| 517 | { |
| 518 | tputs(sc_eol_clear, 1, putchr); |
| 519 | } |
| 520 | |
| 521 | /* |
| 522 | * Begin "standout" (bold, underline, or whatever). |
| 523 | */ |
| 524 | public void |
| 525 | so_enter() |
| 526 | { |
| 527 | tputs(sc_s_in, 1, putchr); |
| 528 | } |
| 529 | |
| 530 | /* |
| 531 | * End "standout". |
| 532 | */ |
| 533 | public void |
| 534 | so_exit() |
| 535 | { |
| 536 | tputs(sc_s_out, 1, putchr); |
| 537 | } |
| 538 | |
| 539 | /* |
| 540 | * Begin "underline" (hopefully real underlining, |
| 541 | * otherwise whatever the terminal provides). |
| 542 | */ |
| 543 | public void |
| 544 | ul_enter() |
| 545 | { |
| 546 | tputs(sc_u_in, 1, putchr); |
| 547 | } |
| 548 | |
| 549 | /* |
| 550 | * End "underline". |
| 551 | */ |
| 552 | public void |
| 553 | ul_exit() |
| 554 | { |
| 555 | tputs(sc_u_out, 1, putchr); |
| 556 | } |
| 557 | |
| 558 | /* |
| 559 | * Begin "bold" |
| 560 | */ |
| 561 | public void |
| 562 | bo_enter() |
| 563 | { |
| 564 | tputs(sc_b_in, 1, putchr); |
| 565 | } |
| 566 | |
| 567 | /* |
| 568 | * End "bold". |
| 569 | */ |
| 570 | public void |
| 571 | bo_exit() |
| 572 | { |
| 573 | tputs(sc_b_out, 1, putchr); |
| 574 | } |
| 575 | |
| 576 | /* |
| 577 | * Erase the character to the left of the cursor |
| 578 | * and move the cursor left. |
| 579 | */ |
| 580 | public void |
| 581 | backspace() |
| 582 | { |
| 583 | /* |
| 584 | * Try to erase the previous character by overstriking with a space. |
| 585 | */ |
| 586 | tputs(sc_backspace, 1, putchr); |
| 587 | putchr(' '); |
| 588 | tputs(sc_backspace, 1, putchr); |
| 589 | } |
| 590 | |
| 591 | /* |
| 592 | * Output a plain backspace, without erasing the previous char. |
| 593 | */ |
| 594 | public void |
| 595 | putbs() |
| 596 | { |
| 597 | tputs(sc_backspace, 1, putchr); |
| 598 | } |