screen.c revision 1.2
1 /* 2 * Copyright (c) 1988 Mark Nudleman 3 * Copyright (c) 1988, 1993 4 * The Regents of the University of California. All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 3. All advertising materials mentioning features or use of this software 15 * must display the following acknowledgement: 16 * This product includes software developed by the University of 17 * California, Berkeley and its contributors. 18 * 4. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35 #ifndef lint 36 static char sccsid[] = "@(#)screen.c 8.2 (Berkeley) 4/20/94"; 37 #endif /* not lint */ 38 39 /* 40 * Routines which deal with the characteristics of the terminal. 41 * Uses termcap to be as terminal-independent as possible. 42 * 43 * {{ Someday this should be rewritten to use curses. }} 44 */ 45 46 #include <stdio.h> 47 #include <string.h> 48 #include <less.h> 49 50 #define TERMIOS 1 51 52 #if TERMIO 53 #include <termio.h> 54 #else 55 #if TERMIOS 56 #include <termios.h> 57 #define TAB3 0 58 #include <sys/ioctl.h> 59 #else 60 #include <sgtty.h> 61 #endif 62 #endif 63 64 #ifdef TIOCGWINSZ 65 #include <sys/ioctl.h> 66 #else 67 /* 68 * For the Unix PC (ATT 7300 & 3B1): 69 * Since WIOCGETD is defined in sys/window.h, we can't use that to decide 70 * whether to include sys/window.h. Use SIGPHONE from sys/signal.h instead. 71 */ 72 #include <sys/signal.h> 73 #ifdef SIGPHONE 74 #include <sys/window.h> 75 #endif 76 #endif 77 78 /* 79 * Strings passed to tputs() to do various terminal functions. 80 */ 81 static char 82 *sc_pad, /* Pad string */ 83 *sc_home, /* Cursor home */ 84 *sc_addline, /* Add line, scroll down following lines */ 85 *sc_lower_left, /* Cursor to last line, first column */ 86 *sc_move, /* General cursor positioning */ 87 *sc_clear, /* Clear screen */ 88 *sc_eol_clear, /* Clear to end of line */ 89 *sc_s_in, /* Enter standout (highlighted) mode */ 90 *sc_s_out, /* Exit standout mode */ 91 *sc_u_in, /* Enter underline mode */ 92 *sc_u_out, /* Exit underline mode */ 93 *sc_b_in, /* Enter bold mode */ 94 *sc_b_out, /* Exit bold mode */ 95 *sc_backspace, /* Backspace cursor */ 96 *sc_init, /* Startup terminal initialization */ 97 *sc_deinit; /* Exit terminal de-intialization */ 98 99 int auto_wrap; /* Terminal does \r\n when write past margin */ 100 int ignaw; /* Terminal ignores \n immediately after wrap */ 101 /* The user's erase and line-kill chars */ 102 int retain_below; /* Terminal retains text below the screen */ 103 int erase_char, kill_char, werase_char; 104 int sc_width, sc_height = -1; /* Height & width of screen */ 105 int sc_window = -1; /* window size for forward and backward */ 106 int bo_width, be_width; /* Printing width of boldface sequences */ 107 int ul_width, ue_width; /* Printing width of underline sequences */ 108 int so_width, se_width; /* Printing width of standout sequences */ 109 110 /* 111 * These two variables are sometimes defined in, 112 * and needed by, the termcap library. 113 * It may be necessary on some systems to declare them extern here. 114 */ 115 /*extern*/ short ospeed; /* Terminal output baud rate */ 116 /*extern*/ char PC; /* Pad character */ 117 118 extern int back_scroll; 119 char *tgetstr(); 120 char *tgoto(); 121 122 /* 123 * Change terminal to "raw mode", or restore to "normal" mode. 124 * "Raw mode" means 125 * 1. An outstanding read will complete on receipt of a single keystroke. 126 * 2. Input is not echoed. 127 * 3. On output, \n is mapped to \r\n. 128 * 4. \t is NOT expanded into spaces. 129 * 5. Signal-causing characters such as ctrl-C (interrupt), 130 * etc. are NOT disabled. 131 * It doesn't matter whether an input \n is mapped to \r, or vice versa. 132 */ 133 raw_mode(on) 134 int on; 135 { 136 #if TERMIO || TERMIOS 137 138 #if TERMIO 139 struct termio s; 140 static struct termio save_term; 141 #else 142 struct termios s; 143 static struct termios save_term; 144 #endif 145 146 if (on) 147 { 148 /* 149 * Get terminal modes. 150 */ 151 #if TERMIO 152 (void)ioctl(2, TCGETA, &s); 153 #else 154 tcgetattr(2, &s); 155 #endif 156 157 /* 158 * Save modes and set certain variables dependent on modes. 159 */ 160 save_term = s; 161 #if TERMIO 162 ospeed = s.c_cflag & CBAUD; 163 #else 164 ospeed = cfgetospeed(&s); 165 #endif 166 erase_char = s.c_cc[VERASE]; 167 kill_char = s.c_cc[VKILL]; 168 werase_char = s.c_cc[VWERASE]; 169 170 /* 171 * Set the modes to the way we want them. 172 */ 173 s.c_lflag &= ~(ICANON|ECHO|ECHOE|ECHOK|ECHONL); 174 s.c_oflag |= (OPOST|ONLCR|TAB3); 175 #if TERMIO 176 s.c_oflag &= ~(OCRNL|ONOCR|ONLRET); 177 #endif 178 s.c_cc[VMIN] = 1; 179 s.c_cc[VTIME] = 0; 180 } else 181 { 182 /* 183 * Restore saved modes. 184 */ 185 s = save_term; 186 } 187 #if TERMIO 188 (void)ioctl(2, TCSETAW, &s); 189 #else 190 tcsetattr(2, TCSADRAIN, &s); 191 #endif 192 #else 193 struct sgttyb s; 194 struct ltchars l; 195 static struct sgttyb save_term; 196 197 if (on) 198 { 199 /* 200 * Get terminal modes. 201 */ 202 (void)ioctl(2, TIOCGETP, &s); 203 (void)ioctl(2, TIOCGLTC, &l); 204 205 /* 206 * Save modes and set certain variables dependent on modes. 207 */ 208 save_term = s; 209 ospeed = s.sg_ospeed; 210 erase_char = s.sg_erase; 211 kill_char = s.sg_kill; 212 werase_char = l.t_werasc; 213 214 /* 215 * Set the modes to the way we want them. 216 */ 217 s.sg_flags |= CBREAK; 218 s.sg_flags &= ~(ECHO|XTABS); 219 } else 220 { 221 /* 222 * Restore saved modes. 223 */ 224 s = save_term; 225 } 226 (void)ioctl(2, TIOCSETN, &s); 227 #endif 228 } 229 230 /* 231 * Get terminal capabilities via termcap. 232 */ 233 get_term() 234 { 235 char termbuf[2048]; 236 char *sp; 237 char *term; 238 int hard; 239 #ifdef TIOCGWINSZ 240 struct winsize w; 241 #else 242 #ifdef WIOCGETD 243 struct uwdata w; 244 #endif 245 #endif 246 static char sbuf[1024]; 247 248 char *getenv(), *strcpy(); 249 250 /* 251 * Find out what kind of terminal this is. 252 */ 253 if ((term = getenv("TERM")) == NULL) 254 term = "unknown"; 255 if (tgetent(termbuf, term) <= 0) 256 (void)strcpy(termbuf, "dumb:co#80:hc:"); 257 258 /* 259 * Get size of the screen. 260 */ 261 #ifdef TIOCGWINSZ 262 if (ioctl(2, TIOCGWINSZ, &w) == 0 && w.ws_row > 0) 263 sc_height = w.ws_row; 264 #else 265 #ifdef WIOCGETD 266 if (ioctl(2, WIOCGETD, &w) == 0 && w.uw_height > 0) 267 sc_height = w.uw_height/w.uw_vs; 268 #endif 269 #endif 270 else 271 sc_height = tgetnum("li"); 272 hard = (sc_height < 0 || tgetflag("hc")); 273 if (hard) { 274 /* Oh no, this is a hardcopy terminal. */ 275 sc_height = 24; 276 } 277 278 #ifdef TIOCGWINSZ 279 if (ioctl(2, TIOCGWINSZ, &w) == 0 && w.ws_col > 0) 280 sc_width = w.ws_col; 281 else 282 #ifdef WIOCGETD 283 if (ioctl(2, WIOCGETD, &w) == 0 && w.uw_width > 0) 284 sc_width = w.uw_width/w.uw_hs; 285 else 286 #endif 287 #endif 288 sc_width = tgetnum("co"); 289 if (sc_width < 0) 290 sc_width = 80; 291 292 auto_wrap = tgetflag("am"); 293 ignaw = tgetflag("xn"); 294 retain_below = tgetflag("db"); 295 296 /* 297 * Assumes termcap variable "sg" is the printing width of 298 * the standout sequence, the end standout sequence, 299 * the underline sequence, the end underline sequence, 300 * the boldface sequence, and the end boldface sequence. 301 */ 302 if ((so_width = tgetnum("sg")) < 0) 303 so_width = 0; 304 be_width = bo_width = ue_width = ul_width = se_width = so_width; 305 306 /* 307 * Get various string-valued capabilities. 308 */ 309 sp = sbuf; 310 311 sc_pad = tgetstr("pc", &sp); 312 if (sc_pad != NULL) 313 PC = *sc_pad; 314 315 sc_init = tgetstr("ti", &sp); 316 if (sc_init == NULL) 317 sc_init = ""; 318 319 sc_deinit= tgetstr("te", &sp); 320 if (sc_deinit == NULL) 321 sc_deinit = ""; 322 323 sc_eol_clear = tgetstr("ce", &sp); 324 if (hard || sc_eol_clear == NULL || *sc_eol_clear == '\0') 325 { 326 sc_eol_clear = ""; 327 } 328 329 sc_clear = tgetstr("cl", &sp); 330 if (hard || sc_clear == NULL || *sc_clear == '\0') 331 { 332 sc_clear = "\n\n"; 333 } 334 335 sc_move = tgetstr("cm", &sp); 336 if (hard || sc_move == NULL || *sc_move == '\0') 337 { 338 /* 339 * This is not an error here, because we don't 340 * always need sc_move. 341 * We need it only if we don't have home or lower-left. 342 */ 343 sc_move = ""; 344 } 345 346 sc_s_in = tgetstr("so", &sp); 347 if (hard || sc_s_in == NULL) 348 sc_s_in = ""; 349 350 sc_s_out = tgetstr("se", &sp); 351 if (hard || sc_s_out == NULL) 352 sc_s_out = ""; 353 354 sc_u_in = tgetstr("us", &sp); 355 if (hard || sc_u_in == NULL) 356 sc_u_in = sc_s_in; 357 358 sc_u_out = tgetstr("ue", &sp); 359 if (hard || sc_u_out == NULL) 360 sc_u_out = sc_s_out; 361 362 sc_b_in = tgetstr("md", &sp); 363 if (hard || sc_b_in == NULL) 364 { 365 sc_b_in = sc_s_in; 366 sc_b_out = sc_s_out; 367 } else 368 { 369 sc_b_out = tgetstr("me", &sp); 370 if (hard || sc_b_out == NULL) 371 sc_b_out = ""; 372 } 373 374 sc_home = tgetstr("ho", &sp); 375 if (hard || sc_home == NULL || *sc_home == '\0') 376 { 377 if (*sc_move == '\0') 378 { 379 /* 380 * This last resort for sc_home is supposed to 381 * be an up-arrow suggesting moving to the 382 * top of the "virtual screen". (The one in 383 * your imagination as you try to use this on 384 * a hard copy terminal.) 385 */ 386 sc_home = "|\b^"; 387 } else 388 { 389 /* 390 * No "home" string, 391 * but we can use "move(0,0)". 392 */ 393 (void)strcpy(sp, tgoto(sc_move, 0, 0)); 394 sc_home = sp; 395 sp += strlen(sp) + 1; 396 } 397 } 398 399 sc_lower_left = tgetstr("ll", &sp); 400 if (hard || sc_lower_left == NULL || *sc_lower_left == '\0') 401 { 402 if (*sc_move == '\0') 403 { 404 sc_lower_left = "\r"; 405 } else 406 { 407 /* 408 * No "lower-left" string, 409 * but we can use "move(0,last-line)". 410 */ 411 (void)strcpy(sp, tgoto(sc_move, 0, sc_height-1)); 412 sc_lower_left = sp; 413 sp += strlen(sp) + 1; 414 } 415 } 416 417 /* 418 * To add a line at top of screen and scroll the display down, 419 * we use "al" (add line) or "sr" (scroll reverse). 420 */ 421 if ((sc_addline = tgetstr("al", &sp)) == NULL || 422 *sc_addline == '\0') 423 sc_addline = tgetstr("sr", &sp); 424 425 if (hard || sc_addline == NULL || *sc_addline == '\0') 426 { 427 sc_addline = ""; 428 /* Force repaint on any backward movement */ 429 back_scroll = 0; 430 } 431 432 if (tgetflag("bs")) 433 sc_backspace = "\b"; 434 else 435 { 436 sc_backspace = tgetstr("bc", &sp); 437 if (sc_backspace == NULL || *sc_backspace == '\0') 438 sc_backspace = "\b"; 439 } 440 } 441 442 443 /* 444 * Below are the functions which perform all the 445 * terminal-specific screen manipulation. 446 */ 447 448 int putchr(); 449 450 /* 451 * Initialize terminal 452 */ 453 init() 454 { 455 tputs(sc_init, sc_height, putchr); 456 } 457 458 /* 459 * Deinitialize terminal 460 */ 461 deinit() 462 { 463 tputs(sc_deinit, sc_height, putchr); 464 } 465 466 /* 467 * Home cursor (move to upper left corner of screen). 468 */ 469 home() 470 { 471 tputs(sc_home, 1, putchr); 472 } 473 474 /* 475 * Add a blank line (called with cursor at home). 476 * Should scroll the display down. 477 */ 478 add_line() 479 { 480 tputs(sc_addline, sc_height, putchr); 481 } 482 483 int short_file; /* if file less than a screen */ 484 lower_left() 485 { 486 if (short_file) { 487 putchr('\r'); 488 flush(); 489 } 490 else 491 tputs(sc_lower_left, 1, putchr); 492 } 493 494 /* 495 * Ring the terminal bell. 496 */ 497 bell() 498 { 499 putchr('\7'); 500 } 501 502 /* 503 * Clear the screen. 504 */ 505 clear() 506 { 507 tputs(sc_clear, sc_height, putchr); 508 } 509 510 /* 511 * Clear from the cursor to the end of the cursor's line. 512 * {{ This must not move the cursor. }} 513 */ 514 clear_eol() 515 { 516 tputs(sc_eol_clear, 1, putchr); 517 } 518 519 /* 520 * Begin "standout" (bold, underline, or whatever). 521 */ 522 so_enter() 523 { 524 tputs(sc_s_in, 1, putchr); 525 } 526 527 /* 528 * End "standout". 529 */ 530 so_exit() 531 { 532 tputs(sc_s_out, 1, putchr); 533 } 534 535 /* 536 * Begin "underline" (hopefully real underlining, 537 * otherwise whatever the terminal provides). 538 */ 539 ul_enter() 540 { 541 tputs(sc_u_in, 1, putchr); 542 } 543 544 /* 545 * End "underline". 546 */ 547 ul_exit() 548 { 549 tputs(sc_u_out, 1, putchr); 550 } 551 552 /* 553 * Begin "bold" 554 */ 555 bo_enter() 556 { 557 tputs(sc_b_in, 1, putchr); 558 } 559 560 /* 561 * End "bold". 562 */ 563 bo_exit() 564 { 565 tputs(sc_b_out, 1, putchr); 566 } 567 568 /* 569 * Erase the character to the left of the cursor 570 * and move the cursor left. 571 */ 572 backspace() 573 { 574 /* 575 * Try to erase the previous character by overstriking with a space. 576 */ 577 tputs(sc_backspace, 1, putchr); 578 putchr(' '); 579 tputs(sc_backspace, 1, putchr); 580 } 581 582 /* 583 * Output a plain backspace, without erasing the previous char. 584 */ 585 putbs() 586 { 587 tputs(sc_backspace, 1, putchr); 588 } 589
Indexes created Sat Sep 27 22:09:54 GMT 2025