1 /*
2 * Routines which deal with the characteristics of the terminal.
3 * Uses termcap to be as terminal-independent as possible.
4 *
5 * {{ Someday this should be rewritten to use curses. }}
6 */
7
8 #include "less.h"
9 #if XENIX
10 #include <sys/types.h>
11 #include <sys/ioctl.h>
12 #endif
13
14 #if TERMIO
15 # ifdef BSD4_4
16 #if !defined(__DragonFly__) && !defined(__FreeBSD__)
17 #include <sys/termios.h>
18 #else
19 #include <termios.h>
20 #endif
21 # else
22 #include <termio.h>
23 # endif
24 #else
25 #include <sgtty.h>
26 #endif
27
28 #ifdef TIOCGWINSZ
29 #include <sys/ioctl.h>
30 #else
31 /*
32 * For the Unix PC (ATT 7300 & 3B1):
33 * Since WIOCGETD is defined in sys/window.h, we can't use that to decide
34 * whether to include sys/window.h. Use SIGPHONE from sys/signal.h instead.
35 */
36 #include <signal.h>
37 #ifdef SIGPHONE
38 #include <sys/window.h>
39 #endif
40 #endif
41
42 /*
43 * Strings passed to tputs() to do various terminal functions.
44 */
45 static char
46 *sc_pad, /* Pad string */
47 *sc_home, /* Cursor home */
48 *sc_addline, /* Add line, scroll down following lines */
49 *sc_lower_left, /* Cursor to last line, first column */
50 *sc_move, /* General cursor positioning */
51 *sc_clear, /* Clear screen */
52 *sc_eol_clear, /* Clear to end of line */
53 *sc_s_in, /* Enter standout (highlighted) mode */
54 *sc_s_out, /* Exit standout mode */
55 *sc_u_in, /* Enter underline mode */
56 *sc_u_out, /* Exit underline mode */
57 *sc_b_in, /* Enter bold mode */
58 *sc_b_out, /* Exit bold mode */
59 *sc_visual_bell, /* Visual bell (flash screen) sequence */
60 *sc_backspace, /* Backspace cursor */
61 *sc_init, /* Startup terminal initialization */
62 *sc_deinit; /* Exit terminal de-intialization */
63
64 public int auto_wrap; /* Terminal does \r\n when write past margin */
65 public int ignaw; /* Terminal ignores \n immediately after wrap */
66 public int erase_char, kill_char; /* The user's erase and line-kill chars */
67 public int sc_width, sc_height; /* Height & width of screen */
68 public int sc_window = -1; /* window size for forward and backward */
69 public int bo_width, be_width; /* Printing width of boldface sequences */
70 public int ul_width, ue_width; /* Printing width of underline sequences */
71 public int so_width, se_width; /* Printing width of standout sequences */
72
73 /*
74 * These two variables are sometimes defined in,
75 * and needed by, the termcap library.
76 * It may be necessary on some systems to declare them extern here.
77 */
78 /*extern*/ short ospeed; /* Terminal output baud rate */
79 /*extern*/ char PC; /* Pad character */
80
81 extern int quiet; /* If VERY_QUIET, use visual bell for bell */
82 extern int know_dumb; /* Don't complain about a dumb terminal */
83 extern int back_scroll;
84 char *tgetstr();
85 char *tgoto();
86
87 /*
88 * Change terminal to "raw mode", or restore to "normal" mode.
89 * "Raw mode" means
90 * 1. An outstanding read will complete on receipt of a single keystroke.
91 * 2. Input is not echoed.
92 * 3. On output, \n is mapped to \r\n.
93 * 4. \t is NOT expanded into spaces.
94 * 5. Signal-causing characters such as ctrl-C (interrupt),
95 * etc. are NOT disabled.
96 * It doesn't matter whether an input \n is mapped to \r, or vice versa.
97 */
98 public void
raw_mode(on)99 raw_mode(on)
100 int on;
101 {
102 #if TERMIO
103 #ifdef BSD4_4
104 struct termios s;
105 static struct termios save_term;
106 #else
107 struct termio s;
108 static struct termio save_term;
109 #endif
110
111 if (on)
112 {
113 /*
114 * Get terminal modes.
115 */
116 #ifdef BSD4_4
117 tcgetattr(2, &s);
118 #else
119 ioctl(2, TCGETA, &s);
120 #endif
121
122 /*
123 * Save modes and set certain variables dependent on modes.
124 */
125 save_term = s;
126 ospeed =
127 #ifdef BSD4_4
128 cfgetospeed(&s);
129 #else
130 s.c_cflag & CBAUD;
131 #endif
132 erase_char = s.c_cc[VERASE];
133 kill_char = s.c_cc[VKILL];
134
135 /*
136 * Set the modes to the way we want them.
137 */
138 s.c_lflag &= ~(ICANON|ECHO|ECHOE|ECHOK|ECHONL);
139 s.c_oflag |=
140 #ifdef BSD4_4
141 (OPOST|ONLCR|OXTABS);
142 #else
143 (OPOST|ONLCR|TABS3);
144 #endif
145 s.c_oflag &= ~(OCRNL|ONOCR|ONLRET);
146 s.c_cc[VMIN] = 1;
147 s.c_cc[VTIME] = 0;
148 } else
149 {
150 /*
151 * Restore saved modes.
152 */
153 s = save_term;
154 }
155 # ifdef BSD4_4
156 tcsetattr(2, TCSANOW, &s);
157 # else
158 ioctl(2, TCSETAW, &s);
159 # endif
160 #else
161 struct sgttyb s;
162 static struct sgttyb save_term;
163
164 if (on)
165 {
166 /*
167 * Get terminal modes.
168 */
169 ioctl(2, TIOCGETP, &s);
170
171 /*
172 * Save modes and set certain variables dependent on modes.
173 */
174 save_term = s;
175 ospeed = s.sg_ospeed;
176 erase_char = s.sg_erase;
177 kill_char = s.sg_kill;
178
179 /*
180 * Set the modes to the way we want them.
181 */
182 s.sg_flags |= CBREAK;
183 s.sg_flags &= ~(ECHO|XTABS);
184 } else
185 {
186 /*
187 * Restore saved modes.
188 */
189 s = save_term;
190 }
191 ioctl(2, TIOCSETP, &s);
192 #endif
193 }
194
195 static void
cannot(s)196 cannot(s)
197 char *s;
198 {
199 char message[100];
200
201 if (know_dumb)
202 /*
203 * He knows he has a dumb terminal, so don't tell him.
204 */
205 return;
206
207 sprintf(message, "WARNING: terminal cannot \"%s\"", s);
208 error(message);
209 }
210
211 /*
212 * Get terminal capabilities via termcap.
213 */
214 public void
get_term()215 get_term()
216 {
217 char termbuf[2048];
218 char *sp;
219 char *term;
220 int hard;
221 #ifdef TIOCGWINSZ
222 struct winsize w;
223 #else
224 #ifdef WIOCGETD
225 struct uwdata w;
226 #endif
227 #endif
228 static char sbuf[1024];
229
230 char *getenv();
231
232 /*
233 * Find out what kind of terminal this is.
234 */
235 if ((term = getenv("TERM")) == NULL)
236 term = "unknown";
237 if (tgetent(termbuf, term) <= 0)
238 strcpy(termbuf, "dumb:co#80:hc:");
239
240 /*
241 * Get size of the screen.
242 */
243 #ifdef TIOCGWINSZ
244 if (ioctl(2, TIOCGWINSZ, &w) == 0 && w.ws_row > 0)
245 sc_height = w.ws_row;
246 else
247 #else
248 #ifdef WIOCGETD
249 if (ioctl(2, WIOCGETD, &w) == 0 && w.uw_height > 0)
250 sc_height = w.uw_height/w.uw_vs;
251 else
252 #endif
253 #endif
254 sc_height = tgetnum("li");
255 hard = (sc_height < 0 || tgetflag("hc"));
256 if (hard)
257 {
258 /* Oh no, this is a hardcopy terminal. */
259 sc_height = 24;
260 }
261
262 #ifdef TIOCGWINSZ
263 if (ioctl(2, TIOCGWINSZ, &w) == 0 && w.ws_col > 0)
264 sc_width = w.ws_col;
265 else
266 #ifdef WIOCGETD
267 if (ioctl(2, WIOCGETD, &w) == 0 && w.uw_width > 0)
268 sc_width = w.uw_width/w.uw_hs;
269 else
270 #endif
271 #endif
272 sc_width = tgetnum("co");
273 if (sc_width < 0)
274 sc_width = 80;
275
276 auto_wrap = tgetflag("am");
277 ignaw = tgetflag("xn");
278
279 /*
280 * Assumes termcap variable "sg" is the printing width of
281 * the standout sequence, the end standout sequence,
282 * the underline sequence, the end underline sequence,
283 * the boldface sequence, and the end boldface sequence.
284 */
285 if ((so_width = tgetnum("sg")) < 0)
286 so_width = 0;
287 be_width = bo_width = ue_width = ul_width = se_width = so_width;
288
289 /*
290 * Get various string-valued capabilities.
291 */
292 sp = sbuf;
293
294 sc_pad = tgetstr("pc", &sp);
295 if (sc_pad != NULL)
296 PC = *sc_pad;
297
298 sc_init = tgetstr("ti", &sp);
299 if (sc_init == NULL)
300 sc_init = "";
301
302 sc_deinit= tgetstr("te", &sp);
303 if (sc_deinit == NULL)
304 sc_deinit = "";
305
306 sc_eol_clear = tgetstr("ce", &sp);
307 if (hard || sc_eol_clear == NULL || *sc_eol_clear == '\0')
308 {
309 cannot("clear to end of line");
310 sc_eol_clear = "";
311 }
312
313 sc_clear = tgetstr("cl", &sp);
314 if (hard || sc_clear == NULL || *sc_clear == '\0')
315 {
316 cannot("clear screen");
317 sc_clear = "\n\n";
318 }
319
320 sc_move = tgetstr("cm", &sp);
321 if (hard || sc_move == NULL || *sc_move == '\0')
322 {
323 /*
324 * This is not an error here, because we don't
325 * always need sc_move.
326 * We need it only if we don't have home or lower-left.
327 */
328 sc_move = "";
329 }
330
331 sc_s_in = tgetstr("so", &sp);
332 if (hard || sc_s_in == NULL)
333 sc_s_in = "";
334
335 sc_s_out = tgetstr("se", &sp);
336 if (hard || sc_s_out == NULL)
337 sc_s_out = "";
338
339 sc_u_in = tgetstr("us", &sp);
340 if (hard || sc_u_in == NULL)
341 sc_u_in = sc_s_in;
342
343 sc_u_out = tgetstr("ue", &sp);
344 if (hard || sc_u_out == NULL)
345 sc_u_out = sc_s_out;
346
347 sc_b_in = tgetstr("md", &sp);
348 if (hard || sc_b_in == NULL)
349 {
350 sc_b_in = sc_s_in;
351 sc_b_out = sc_s_out;
352 } else
353 {
354 sc_b_out = tgetstr("me", &sp);
355 if (hard || sc_b_out == NULL)
356 sc_b_out = "";
357 }
358
359 sc_visual_bell = tgetstr("vb", &sp);
360 if (hard || sc_visual_bell == NULL)
361 sc_visual_bell = "";
362
363 sc_home = tgetstr("ho", &sp);
364 if (hard || sc_home == NULL || *sc_home == '\0')
365 {
366 if (*sc_move == '\0')
367 {
368 cannot("home cursor");
369 /*
370 * This last resort for sc_home is supposed to
371 * be an up-arrow suggesting moving to the
372 * top of the "virtual screen". (The one in
373 * your imagination as you try to use this on
374 * a hard copy terminal.)
375 */
376 sc_home = "|\b^";
377 } else
378 {
379 /*
380 * No "home" string,
381 * but we can use "move(0,0)".
382 */
383 strcpy(sp, tgoto(sc_move, 0, 0));
384 sc_home = sp;
385 sp += strlen(sp) + 1;
386 }
387 }
388
389 sc_lower_left = tgetstr("ll", &sp);
390 if (hard || sc_lower_left == NULL || *sc_lower_left == '\0')
391 {
392 if (*sc_move == '\0')
393 {
394 cannot("move cursor to lower left of screen");
395 sc_lower_left = "\r";
396 } else
397 {
398 /*
399 * No "lower-left" string,
400 * but we can use "move(0,last-line)".
401 */
402 strcpy(sp, tgoto(sc_move, 0, sc_height-1));
403 sc_lower_left = sp;
404 sp += strlen(sp) + 1;
405 }
406 }
407
408 /*
409 * To add a line at top of screen and scroll the display down,
410 * we use "al" (add line) or "sr" (scroll reverse).
411 */
412 if ((sc_addline = tgetstr("al", &sp)) == NULL ||
413 *sc_addline == '\0')
414 sc_addline = tgetstr("sr", &sp);
415
416 if (hard || sc_addline == NULL || *sc_addline == '\0')
417 {
418 cannot("scroll backwards");
419 sc_addline = "";
420 /* Force repaint on any backward movement */
421 back_scroll = 0;
422 }
423
424 if (tgetflag("bs"))
425 sc_backspace = "\b";
426 else
427 {
428 sc_backspace = tgetstr("bc", &sp);
429 if (sc_backspace == NULL || *sc_backspace == '\0')
430 sc_backspace = "\b";
431 }
432 }
433
434
435 /*
436 * Below are the functions which perform all the
437 * terminal-specific screen manipulation.
438 */
439
440
441 /*
442 * Initialize terminal
443 */
444 public void
init()445 init()
446 {
447 tputs(sc_init, sc_height, putchr);
448 }
449
450 /*
451 * Deinitialize terminal
452 */
453 public void
deinit()454 deinit()
455 {
456 tputs(sc_deinit, sc_height, putchr);
457 }
458
459 /*
460 * Home cursor (move to upper left corner of screen).
461 */
462 public void
home()463 home()
464 {
465 tputs(sc_home, 1, putchr);
466 }
467
468 /*
469 * Add a blank line (called with cursor at home).
470 * Should scroll the display down.
471 */
472 public void
add_line()473 add_line()
474 {
475 tputs(sc_addline, sc_height, putchr);
476 }
477
478 /*
479 * Move cursor to lower left corner of screen.
480 */
481 public void
lower_left()482 lower_left()
483 {
484 tputs(sc_lower_left, 1, putchr);
485 }
486
487 /*
488 * Ring the terminal bell.
489 */
490 public void
bell()491 bell()
492 {
493 if (quiet == VERY_QUIET)
494 vbell();
495 else
496 putchr('\7');
497 }
498
499 /*
500 * Output the "visual bell", if there is one.
501 */
502 public void
vbell()503 vbell()
504 {
505 if (*sc_visual_bell == '\0')
506 return;
507 tputs(sc_visual_bell, sc_height, putchr);
508 }
509
510 /*
511 * Clear the screen.
512 */
513 public void
clearscr()514 clearscr()
515 {
516 tputs(sc_clear, sc_height, putchr);
517 }
518
519 /*
520 * Clear from the cursor to the end of the cursor's line.
521 * {{ This must not move the cursor. }}
522 */
523 public void
clear_eol()524 clear_eol()
525 {
526 tputs(sc_eol_clear, 1, putchr);
527 }
528
529 /*
530 * Begin "standout" (bold, underline, or whatever).
531 */
532 public void
so_enter()533 so_enter()
534 {
535 tputs(sc_s_in, 1, putchr);
536 }
537
538 /*
539 * End "standout".
540 */
541 public void
so_exit()542 so_exit()
543 {
544 tputs(sc_s_out, 1, putchr);
545 }
546
547 /*
548 * Begin "underline" (hopefully real underlining,
549 * otherwise whatever the terminal provides).
550 */
551 public void
ul_enter()552 ul_enter()
553 {
554 tputs(sc_u_in, 1, putchr);
555 }
556
557 /*
558 * End "underline".
559 */
560 public void
ul_exit()561 ul_exit()
562 {
563 tputs(sc_u_out, 1, putchr);
564 }
565
566 /*
567 * Begin "bold"
568 */
569 public void
bo_enter()570 bo_enter()
571 {
572 tputs(sc_b_in, 1, putchr);
573 }
574
575 /*
576 * End "bold".
577 */
578 public void
bo_exit()579 bo_exit()
580 {
581 tputs(sc_b_out, 1, putchr);
582 }
583
584 /*
585 * Erase the character to the left of the cursor
586 * and move the cursor left.
587 */
588 public void
backspace()589 backspace()
590 {
591 /*
592 * Try to erase the previous character by overstriking with a space.
593 */
594 tputs(sc_backspace, 1, putchr);
595 putchr(' ');
596 tputs(sc_backspace, 1, putchr);
597 }
598
599 /*
600 * Output a plain backspace, without erasing the previous char.
601 */
602 public void
putbs()603 putbs()
604 {
605 tputs(sc_backspace, 1, putchr);
606 }
607