1 /* $NetBSD: screen.c,v 1.7 2003/10/13 14:34:25 agc Exp $ */ 2 3 /* 4 * Copyright (c) 1988 Mark Nudelman 5 * Copyright (c) 1988, 1993 6 * The Regents of the University of California. All rights reserved. 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 * 3. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 #include <sys/cdefs.h> 34 #ifndef lint 35 #if 0 36 static char sccsid[] = "@(#)screen.c 8.2 (Berkeley) 4/20/94"; 37 #else 38 __RCSID("$NetBSD: screen.c,v 1.7 2003/10/13 14:34:25 agc Exp $"); 39 #endif 40 #endif /* not lint */ 41 42 /* 43 * Routines which deal with the characteristics of the terminal. 44 * Uses termcap to be as terminal-independent as possible. 45 * 46 * {{ Someday this should be rewritten to use curses. }} 47 */ 48 49 #include <stdio.h> 50 #include <string.h> 51 #include <stdlib.h> 52 #include <unistd.h> 53 54 #include "less.h" 55 #include "extern.h" 56 57 #define TERMIOS 1 58 59 #if TERMIO 60 #include <termio.h> 61 #else 62 #if TERMIOS 63 #include <termios.h> 64 #define TAB3 0 65 #include <sys/ioctl.h> 66 #else 67 #include <sgtty.h> 68 #endif 69 #endif 70 #ifdef __NetBSD__ 71 #include <termcap.h> 72 #endif 73 74 #ifdef TIOCGWINSZ 75 #include <sys/ioctl.h> 76 #else 77 /* 78 * For the Unix PC (ATT 7300 & 3B1): 79 * Since WIOCGETD is defined in sys/window.h, we can't use that to decide 80 * whether to include sys/window.h. Use SIGPHONE from sys/signal.h instead. 81 */ 82 #include <sys/signal.h> 83 #ifdef SIGPHONE 84 #include <sys/window.h> 85 #endif 86 #endif 87 88 /* 89 * Strings passed to tputs() to do various terminal functions. 90 */ 91 static char 92 *sc_pad, /* Pad string */ 93 *sc_home, /* Cursor home */ 94 *sc_addline, /* Add line, scroll down following lines */ 95 *sc_lower_left, /* Cursor to last line, first column */ 96 *sc_move, /* General cursor positioning */ 97 *sc_clear, /* Clear screen */ 98 *sc_eol_clear, /* Clear to end of line */ 99 *sc_s_in, /* Enter standout (highlighted) mode */ 100 *sc_s_out, /* Exit standout mode */ 101 *sc_u_in, /* Enter underline mode */ 102 *sc_u_out, /* Exit underline mode */ 103 *sc_b_in, /* Enter bold mode */ 104 *sc_b_out, /* Exit bold mode */ 105 *sc_backspace, /* Backspace cursor */ 106 *sc_init, /* Startup terminal initialization */ 107 *sc_deinit; /* Exit terminal de-intialization */ 108 109 int auto_wrap; /* Terminal does \r\n when write past margin */ 110 int ignaw; /* Terminal ignores \n immediately after wrap */ 111 /* The user's erase and line-kill chars */ 112 int retain_below; /* Terminal retains text below the screen */ 113 int erase_char, kill_char, werase_char; 114 int sc_width, sc_height = -1; /* Height & width of screen */ 115 int sc_window = -1; /* window size for forward and backward */ 116 int bo_width, be_width; /* Printing width of boldface sequences */ 117 int ul_width, ue_width; /* Printing width of underline sequences */ 118 int so_width, se_width; /* Printing width of standout sequences */ 119 120 /* 121 * These two variables are sometimes defined in, 122 * and needed by, the termcap library. 123 * It may be necessary on some systems to declare them extern here. 124 */ 125 /*extern*/ short ospeed; /* Terminal output baud rate */ 126 /*extern*/ char PC; /* Pad character */ 127 128 /* 129 * Change terminal to "raw mode", or restore to "normal" mode. 130 * "Raw mode" means 131 * 1. An outstanding read will complete on receipt of a single keystroke. 132 * 2. Input is not echoed. 133 * 3. On output, \n is mapped to \r\n. 134 * 4. \t is NOT expanded into spaces. 135 * 5. Signal-causing characters such as ctrl-C (interrupt), 136 * etc. are NOT disabled. 137 * It doesn't matter whether an input \n is mapped to \r, or vice versa. 138 */ 139 void 140 raw_mode(on) 141 int on; 142 { 143 #if TERMIO || TERMIOS 144 145 #if TERMIO 146 struct termio s; 147 static struct termio save_term; 148 #else 149 struct termios s; 150 static struct termios save_term; 151 #endif 152 153 if (on) 154 { 155 /* 156 * Get terminal modes. 157 */ 158 #if TERMIO 159 (void)ioctl(2, TCGETA, &s); 160 #else 161 tcgetattr(2, &s); 162 #endif 163 164 /* 165 * Save modes and set certain variables dependent on modes. 166 */ 167 save_term = s; 168 #if TERMIO 169 ospeed = s.c_cflag & CBAUD; 170 #else 171 ospeed = cfgetospeed(&s); 172 #endif 173 erase_char = s.c_cc[VERASE]; 174 kill_char = s.c_cc[VKILL]; 175 werase_char = s.c_cc[VWERASE]; 176 177 /* 178 * Set the modes to the way we want them. 179 */ 180 s.c_lflag &= ~(ICANON|ECHO|ECHOE|ECHOK|ECHONL); 181 s.c_oflag |= (OPOST|ONLCR|TAB3); 182 #if TERMIO 183 s.c_oflag &= ~(OCRNL|ONOCR|ONLRET); 184 #endif 185 s.c_cc[VMIN] = 1; 186 s.c_cc[VTIME] = 0; 187 } else 188 { 189 /* 190 * Restore saved modes. 191 */ 192 s = save_term; 193 } 194 #if TERMIO 195 (void)ioctl(2, TCSETAW, &s); 196 #else 197 tcsetattr(2, TCSADRAIN, &s); 198 #endif 199 #else 200 struct sgttyb s; 201 struct ltchars l; 202 static struct sgttyb save_term; 203 204 if (on) 205 { 206 /* 207 * Get terminal modes. 208 */ 209 (void)ioctl(2, TIOCGETP, &s); 210 (void)ioctl(2, TIOCGLTC, &l); 211 212 /* 213 * Save modes and set certain variables dependent on modes. 214 */ 215 save_term = s; 216 ospeed = s.sg_ospeed; 217 erase_char = s.sg_erase; 218 kill_char = s.sg_kill; 219 werase_char = l.t_werasc; 220 221 /* 222 * Set the modes to the way we want them. 223 */ 224 s.sg_flags |= CBREAK; 225 s.sg_flags &= ~(ECHO|XTABS); 226 } else 227 { 228 /* 229 * Restore saved modes. 230 */ 231 s = save_term; 232 } 233 (void)ioctl(2, TIOCSETN, &s); 234 #endif 235 } 236 237 /* 238 * Get terminal capabilities via termcap. 239 */ 240 void 241 get_term() 242 { 243 char termbuf[2048]; 244 char *sp; 245 char *term; 246 int hard; 247 #ifdef TIOCGWINSZ 248 struct winsize w; 249 #else 250 #ifdef WIOCGETD 251 struct uwdata w; 252 #endif 253 #endif 254 static char sbuf[1024]; 255 256 /* 257 * Find out what kind of terminal this is. 258 */ 259 if ((term = getenv("TERM")) == NULL) 260 term = "unknown"; 261 if (tgetent(termbuf, term) <= 0) 262 (void)strlcpy(termbuf, "dumb:co#80:hc:", sizeof(termbuf)); 263 264 /* 265 * Get size of the screen. 266 */ 267 #ifdef TIOCGWINSZ 268 if (ioctl(2, TIOCGWINSZ, &w) == 0 && w.ws_row > 0) 269 sc_height = w.ws_row; 270 #else 271 #ifdef WIOCGETD 272 if (ioctl(2, WIOCGETD, &w) == 0 && w.uw_height > 0) 273 sc_height = w.uw_height/w.uw_vs; 274 #endif 275 #endif 276 else 277 sc_height = tgetnum("li"); 278 hard = (sc_height < 0 || tgetflag("hc")); 279 if (hard) { 280 /* Oh no, this is a hardcopy terminal. */ 281 sc_height = 24; 282 } 283 284 #ifdef TIOCGWINSZ 285 if (ioctl(2, TIOCGWINSZ, &w) == 0 && w.ws_col > 0) 286 sc_width = w.ws_col; 287 else 288 #ifdef WIOCGETD 289 if (ioctl(2, WIOCGETD, &w) == 0 && w.uw_width > 0) 290 sc_width = w.uw_width/w.uw_hs; 291 else 292 #endif 293 #endif 294 sc_width = tgetnum("co"); 295 if (sc_width < 0) 296 sc_width = 80; 297 298 auto_wrap = tgetflag("am"); 299 ignaw = tgetflag("xn"); 300 retain_below = tgetflag("db"); 301 302 /* 303 * Assumes termcap variable "sg" is the printing width of 304 * the standout sequence, the end standout sequence, 305 * the underline sequence, the end underline sequence, 306 * the boldface sequence, and the end boldface sequence. 307 */ 308 if ((so_width = tgetnum("sg")) < 0) 309 so_width = 0; 310 be_width = bo_width = ue_width = ul_width = se_width = so_width; 311 312 /* 313 * Get various string-valued capabilities. 314 */ 315 sp = sbuf; 316 317 sc_pad = tgetstr("pc", &sp); 318 if (sc_pad != NULL) 319 PC = *sc_pad; 320 321 sc_init = tgetstr("ti", &sp); 322 if (sc_init == NULL) 323 sc_init = ""; 324 325 sc_deinit= tgetstr("te", &sp); 326 if (sc_deinit == NULL) 327 sc_deinit = ""; 328 329 sc_eol_clear = tgetstr("ce", &sp); 330 if (hard || sc_eol_clear == NULL || *sc_eol_clear == '\0') 331 { 332 sc_eol_clear = ""; 333 } 334 335 sc_clear = tgetstr("cl", &sp); 336 if (hard || sc_clear == NULL || *sc_clear == '\0') 337 { 338 sc_clear = "\n\n"; 339 } 340 341 sc_move = tgetstr("cm", &sp); 342 if (hard || sc_move == NULL || *sc_move == '\0') 343 { 344 /* 345 * This is not an error here, because we don't 346 * always need sc_move. 347 * We need it only if we don't have home or lower-left. 348 */ 349 sc_move = ""; 350 } 351 352 sc_s_in = tgetstr("so", &sp); 353 if (hard || sc_s_in == NULL) 354 sc_s_in = ""; 355 356 sc_s_out = tgetstr("se", &sp); 357 if (hard || sc_s_out == NULL) 358 sc_s_out = ""; 359 360 sc_u_in = tgetstr("us", &sp); 361 if (hard || sc_u_in == NULL) 362 sc_u_in = sc_s_in; 363 364 sc_u_out = tgetstr("ue", &sp); 365 if (hard || sc_u_out == NULL) 366 sc_u_out = sc_s_out; 367 368 sc_b_in = tgetstr("md", &sp); 369 if (hard || sc_b_in == NULL) 370 { 371 sc_b_in = sc_s_in; 372 sc_b_out = sc_s_out; 373 } else 374 { 375 sc_b_out = tgetstr("me", &sp); 376 if (hard || sc_b_out == NULL) 377 sc_b_out = ""; 378 } 379 380 sc_home = tgetstr("ho", &sp); 381 if (hard || sc_home == NULL || *sc_home == '\0') 382 { 383 if (*sc_move == '\0') 384 { 385 /* 386 * This last resort for sc_home is supposed to 387 * be an up-arrow suggesting moving to the 388 * top of the "virtual screen". (The one in 389 * your imagination as you try to use this on 390 * a hard copy terminal.) 391 */ 392 sc_home = "|\b^"; 393 } else 394 { 395 /* 396 * No "home" string, 397 * but we can use "move(0,0)". 398 */ 399 (void)strlcpy(sp, tgoto(sc_move, 0, 0), 400 sizeof(sbuf) - (sp - sbuf)); 401 sc_home = sp; 402 sp += strlen(sp) + 1; 403 } 404 } 405 406 sc_lower_left = tgetstr("ll", &sp); 407 if (hard || sc_lower_left == NULL || *sc_lower_left == '\0') 408 { 409 if (*sc_move == '\0') 410 { 411 sc_lower_left = "\r"; 412 } else 413 { 414 /* 415 * No "lower-left" string, 416 * but we can use "move(0,last-line)". 417 */ 418 (void)strlcpy(sp, tgoto(sc_move, 0, sc_height-1), 419 sizeof(sbuf) - (sp - sbuf)); 420 sc_lower_left = sp; 421 sp += strlen(sp) + 1; 422 } 423 } 424 425 /* 426 * To add a line at top of screen and scroll the display down, 427 * we use "al" (add line) or "sr" (scroll reverse). 428 */ 429 if ((sc_addline = tgetstr("al", &sp)) == NULL || 430 *sc_addline == '\0') 431 sc_addline = tgetstr("sr", &sp); 432 433 if (hard || sc_addline == NULL || *sc_addline == '\0') 434 { 435 sc_addline = ""; 436 /* Force repaint on any backward movement */ 437 back_scroll = 0; 438 } 439 440 if (tgetflag("bs")) 441 sc_backspace = "\b"; 442 else 443 { 444 sc_backspace = tgetstr("bc", &sp); 445 if (sc_backspace == NULL || *sc_backspace == '\0') 446 sc_backspace = "\b"; 447 } 448 } 449 450 451 /* 452 * Below are the functions which perform all the 453 * terminal-specific screen manipulation. 454 */ 455 456 /* 457 * Initialize terminal 458 */ 459 void 460 init() 461 { 462 tputs(sc_init, sc_height, putchr); 463 } 464 465 /* 466 * Deinitialize terminal 467 */ 468 void 469 deinit() 470 { 471 tputs(sc_deinit, sc_height, putchr); 472 } 473 474 /* 475 * Home cursor (move to upper left corner of screen). 476 */ 477 void 478 home() 479 { 480 tputs(sc_home, 1, putchr); 481 } 482 483 /* 484 * Add a blank line (called with cursor at home). 485 * Should scroll the display down. 486 */ 487 void 488 add_line() 489 { 490 tputs(sc_addline, sc_height, putchr); 491 } 492 493 int short_file; /* if file less than a screen */ 494 void 495 lower_left() 496 { 497 if (short_file) { 498 putchr('\r'); 499 flush(); 500 } 501 else 502 tputs(sc_lower_left, 1, putchr); 503 } 504 505 /* 506 * Ring the terminal bell. 507 */ 508 void 509 bell() 510 { 511 putchr('\7'); 512 } 513 514 /* 515 * Clear the screen. 516 */ 517 void 518 clear() 519 { 520 tputs(sc_clear, sc_height, putchr); 521 } 522 523 /* 524 * Clear from the cursor to the end of the cursor's line. 525 * {{ This must not move the cursor. }} 526 */ 527 void 528 clear_eol() 529 { 530 tputs(sc_eol_clear, 1, putchr); 531 } 532 533 /* 534 * Begin "standout" (bold, underline, or whatever). 535 */ 536 void 537 so_enter() 538 { 539 tputs(sc_s_in, 1, putchr); 540 } 541 542 /* 543 * End "standout". 544 */ 545 void 546 so_exit() 547 { 548 tputs(sc_s_out, 1, putchr); 549 } 550 551 /* 552 * Begin "underline" (hopefully real underlining, 553 * otherwise whatever the terminal provides). 554 */ 555 void 556 ul_enter() 557 { 558 tputs(sc_u_in, 1, putchr); 559 } 560 561 /* 562 * End "underline". 563 */ 564 void 565 ul_exit() 566 { 567 tputs(sc_u_out, 1, putchr); 568 } 569 570 /* 571 * Begin "bold" 572 */ 573 void 574 bo_enter() 575 { 576 tputs(sc_b_in, 1, putchr); 577 } 578 579 /* 580 * End "bold". 581 */ 582 void 583 bo_exit() 584 { 585 tputs(sc_b_out, 1, putchr); 586 } 587 588 /* 589 * Erase the character to the left of the cursor 590 * and move the cursor left. 591 */ 592 void 593 backspace() 594 { 595 /* 596 * Try to erase the previous character by overstriking with a space. 597 */ 598 tputs(sc_backspace, 1, putchr); 599 putchr(' '); 600 tputs(sc_backspace, 1, putchr); 601 } 602 603 /* 604 * Output a plain backspace, without erasing the previous char. 605 */ 606 void 607 putbs() 608 { 609 tputs(sc_backspace, 1, putchr); 610 } 611
Indexes created Sat Sep 20 22:09:52 GMT 2025