xref: /freebsd/contrib/ncurses/progs/reset_cmd.c (revision 580744621f33383027108364dcadad718df46ffe)
1 /****************************************************************************
2  * Copyright 2019,2020 Thomas E. Dickey                                     *
3  * Copyright 2016,2017 Free Software Foundation, Inc.                       *
4  *                                                                          *
5  * Permission is hereby granted, free of charge, to any person obtaining a  *
6  * copy of this software and associated documentation files (the            *
7  * "Software"), to deal in the Software without restriction, including      *
8  * without limitation the rights to use, copy, modify, merge, publish,      *
9  * distribute, distribute with modifications, sublicense, and/or sell       *
10  * copies of the Software, and to permit persons to whom the Software is    *
11  * furnished to do so, subject to the following conditions:                 *
12  *                                                                          *
13  * The above copyright notice and this permission notice shall be included  *
14  * in all copies or substantial portions of the Software.                   *
15  *                                                                          *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS  *
17  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF               *
18  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.   *
19  * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,   *
20  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR    *
21  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR    *
22  * THE USE OR OTHER DEALINGS IN THE SOFTWARE.                               *
23  *                                                                          *
24  * Except as contained in this notice, the name(s) of the above copyright   *
25  * holders shall not be used in advertising or otherwise to promote the     *
26  * sale, use or other dealings in this Software without prior written       *
27  * authorization.                                                           *
28  ****************************************************************************/
29 
30 /****************************************************************************
31  *  Author: Thomas E. Dickey                                                *
32  ****************************************************************************/
33 
34 #include <reset_cmd.h>
35 #include <tty_settings.h>
36 
37 #include <errno.h>
38 #include <stdio.h>
39 #include <fcntl.h>
40 
41 #if HAVE_SIZECHANGE
42 # if !defined(sun) || !TERMIOS
43 #  if HAVE_SYS_IOCTL_H
44 #   include <sys/ioctl.h>
45 #  endif
46 # endif
47 #endif
48 
49 #if NEED_PTEM_H
50 /* they neglected to define struct winsize in termios.h -- it's only
51    in termio.h	*/
52 #include <sys/stream.h>
53 #include <sys/ptem.h>
54 #endif
55 
56 MODULE_ID("$Id: reset_cmd.c,v 1.19 2020/02/02 23:34:34 tom Exp $")
57 
58 /*
59  * SCO defines TIOCGSIZE and the corresponding struct.  Other systems (SunOS,
60  * Solaris, IRIX) define TIOCGWINSZ and struct winsize.
61  */
62 #ifdef TIOCGSIZE
63 # define IOCTL_GET_WINSIZE TIOCGSIZE
64 # define IOCTL_SET_WINSIZE TIOCSSIZE
65 # define STRUCT_WINSIZE struct ttysize
66 # define WINSIZE_ROWS(n) n.ts_lines
67 # define WINSIZE_COLS(n) n.ts_cols
68 #else
69 # ifdef TIOCGWINSZ
70 #  define IOCTL_GET_WINSIZE TIOCGWINSZ
71 #  define IOCTL_SET_WINSIZE TIOCSWINSZ
72 #  define STRUCT_WINSIZE struct winsize
73 #  define WINSIZE_ROWS(n) n.ws_row
74 #  define WINSIZE_COLS(n) n.ws_col
75 # endif
76 #endif
77 
78 static FILE *my_file;
79 
80 static bool use_reset = FALSE;	/* invoked as reset */
81 static bool use_init = FALSE;	/* invoked as init */
82 
83 static void
84 failed(const char *msg)
85 {
86     int code = errno;
87 
88     (void) fprintf(stderr, "%s: %s: %s\n", _nc_progname, msg, strerror(code));
89     restore_tty_settings();
90     (void) fprintf(my_file, "\n");
91     fflush(my_file);
92     ExitProgram(ErrSystem(code));
93     /* NOTREACHED */
94 }
95 
96 static bool
97 cat_file(char *file)
98 {
99     FILE *fp;
100     size_t nr;
101     char buf[BUFSIZ];
102     bool sent = FALSE;
103 
104     if (file != 0) {
105 	if ((fp = fopen(file, "r")) == 0)
106 	    failed(file);
107 
108 	while ((nr = fread(buf, sizeof(char), sizeof(buf), fp)) != 0) {
109 	    if (fwrite(buf, sizeof(char), nr, my_file) != nr) {
110 		failed(file);
111 	    }
112 	    sent = TRUE;
113 	}
114 	fclose(fp);
115     }
116     return sent;
117 }
118 
119 static int
120 out_char(int c)
121 {
122     return putc(c, my_file);
123 }
124 
125 /**************************************************************************
126  * Mode-setting logic
127  **************************************************************************/
128 
129 /* some BSD systems have these built in, some systems are missing
130  * one or more definitions. The safest solution is to override unless the
131  * commonly-altered ones are defined.
132  */
133 #if !(defined(CERASE) && defined(CINTR) && defined(CKILL) && defined(CQUIT))
134 #undef CEOF
135 #undef CERASE
136 #undef CINTR
137 #undef CKILL
138 #undef CLNEXT
139 #undef CRPRNT
140 #undef CQUIT
141 #undef CSTART
142 #undef CSTOP
143 #undef CSUSP
144 #endif
145 
146 /* control-character defaults */
147 #ifndef CEOF
148 #define CEOF	CTRL('D')
149 #endif
150 #ifndef CERASE
151 #define CERASE	CTRL('H')
152 #endif
153 #ifndef CINTR
154 #define CINTR	127		/* ^? */
155 #endif
156 #ifndef CKILL
157 #define CKILL	CTRL('U')
158 #endif
159 #ifndef CLNEXT
160 #define CLNEXT  CTRL('v')
161 #endif
162 #ifndef CRPRNT
163 #define CRPRNT  CTRL('r')
164 #endif
165 #ifndef CQUIT
166 #define CQUIT	CTRL('\\')
167 #endif
168 #ifndef CSTART
169 #define CSTART	CTRL('Q')
170 #endif
171 #ifndef CSTOP
172 #define CSTOP	CTRL('S')
173 #endif
174 #ifndef CSUSP
175 #define CSUSP	CTRL('Z')
176 #endif
177 
178 #if defined(_POSIX_VDISABLE)
179 #define DISABLED(val)   (((_POSIX_VDISABLE != -1) \
180 		       && ((val) == _POSIX_VDISABLE)) \
181 		      || ((val) <= 0))
182 #else
183 #define DISABLED(val)   ((int)(val) <= 0)
184 #endif
185 
186 #define CHK(val, dft)   (unsigned char) (DISABLED(val) ? dft : val)
187 
188 #define reset_char(item, value) \
189     tty_settings->c_cc[item] = CHK(tty_settings->c_cc[item], value)
190 
191 /*
192  * Reset the terminal mode bits to a sensible state.  Very useful after
193  * a child program dies in raw mode.
194  */
195 void
196 reset_tty_settings(int fd, TTY * tty_settings)
197 {
198     GET_TTY(fd, tty_settings);
199 
200 #ifdef TERMIOS
201 #if defined(VDISCARD) && defined(CDISCARD)
202     reset_char(VDISCARD, CDISCARD);
203 #endif
204     reset_char(VEOF, CEOF);
205     reset_char(VERASE, CERASE);
206 #if defined(VFLUSH) && defined(CFLUSH)
207     reset_char(VFLUSH, CFLUSH);
208 #endif
209     reset_char(VINTR, CINTR);
210     reset_char(VKILL, CKILL);
211 #if defined(VLNEXT) && defined(CLNEXT)
212     reset_char(VLNEXT, CLNEXT);
213 #endif
214     reset_char(VQUIT, CQUIT);
215 #if defined(VREPRINT) && defined(CRPRNT)
216     reset_char(VREPRINT, CRPRNT);
217 #endif
218 #if defined(VSTART) && defined(CSTART)
219     reset_char(VSTART, CSTART);
220 #endif
221 #if defined(VSTOP) && defined(CSTOP)
222     reset_char(VSTOP, CSTOP);
223 #endif
224 #if defined(VSUSP) && defined(CSUSP)
225     reset_char(VSUSP, CSUSP);
226 #endif
227 #if defined(VWERASE) && defined(CWERASE)
228     reset_char(VWERASE, CWERASE);
229 #endif
230 
231     tty_settings->c_iflag &= ~((unsigned) (IGNBRK
232 					   | PARMRK
233 					   | INPCK
234 					   | ISTRIP
235 					   | INLCR
236 					   | IGNCR
237 #ifdef IUCLC
238 					   | IUCLC
239 #endif
240 #ifdef IXANY
241 					   | IXANY
242 #endif
243 					   | IXOFF));
244 
245     tty_settings->c_iflag |= (BRKINT
246 			      | IGNPAR
247 			      | ICRNL
248 			      | IXON
249 #ifdef IMAXBEL
250 			      | IMAXBEL
251 #endif
252 	);
253 
254     tty_settings->c_oflag &= ~((unsigned) (0
255 #ifdef OLCUC
256 					   | OLCUC
257 #endif
258 #ifdef OCRNL
259 					   | OCRNL
260 #endif
261 #ifdef ONOCR
262 					   | ONOCR
263 #endif
264 #ifdef ONLRET
265 					   | ONLRET
266 #endif
267 #ifdef OFILL
268 					   | OFILL
269 #endif
270 #ifdef OFDEL
271 					   | OFDEL
272 #endif
273 #ifdef NLDLY
274 					   | NLDLY
275 #endif
276 #ifdef CRDLY
277 					   | CRDLY
278 #endif
279 #ifdef TABDLY
280 					   | TABDLY
281 #endif
282 #ifdef BSDLY
283 					   | BSDLY
284 #endif
285 #ifdef VTDLY
286 					   | VTDLY
287 #endif
288 #ifdef FFDLY
289 					   | FFDLY
290 #endif
291 			       ));
292 
293     tty_settings->c_oflag |= (OPOST
294 #ifdef ONLCR
295 			      | ONLCR
296 #endif
297 	);
298 
299     tty_settings->c_cflag &= ~((unsigned) (CSIZE
300 					   | CSTOPB
301 					   | PARENB
302 					   | PARODD
303 					   | CLOCAL));
304     tty_settings->c_cflag |= (CS8 | CREAD);
305     tty_settings->c_lflag &= ~((unsigned) (ECHONL
306 					   | NOFLSH
307 #ifdef TOSTOP
308 					   | TOSTOP
309 #endif
310 #ifdef ECHOPTR
311 					   | ECHOPRT
312 #endif
313 #ifdef XCASE
314 					   | XCASE
315 #endif
316 			       ));
317 
318     tty_settings->c_lflag |= (ISIG
319 			      | ICANON
320 			      | ECHO
321 			      | ECHOE
322 			      | ECHOK
323 #ifdef ECHOCTL
324 			      | ECHOCTL
325 #endif
326 #ifdef ECHOKE
327 			      | ECHOKE
328 #endif
329 	);
330 #endif
331 
332     SET_TTY(fd, tty_settings);
333 }
334 
335 /*
336  * Returns a "good" value for the erase character.  This is loosely based on
337  * the BSD4.4 logic.
338  */
339 static int
340 default_erase(void)
341 {
342     int result;
343 
344     if (over_strike
345 	&& VALID_STRING(key_backspace)
346 	&& strlen(key_backspace) == 1) {
347 	result = key_backspace[0];
348     } else {
349 	result = CERASE;
350     }
351 
352     return result;
353 }
354 
355 /*
356  * Update the values of the erase, interrupt, and kill characters in the TTY
357  * parameter.
358  *
359  * SVr4 tset (e.g., Solaris 2.5) only modifies the intr, quit or erase
360  * characters if they're unset, or if we specify them as options.  This differs
361  * from BSD 4.4 tset, which always sets erase.
362  */
363 void
364 set_control_chars(TTY * tty_settings, int my_erase, int my_intr, int my_kill)
365 {
366     if (DISABLED(tty_settings->c_cc[VERASE]) || my_erase >= 0) {
367 	tty_settings->c_cc[VERASE] = UChar((my_erase >= 0)
368 					   ? my_erase
369 					   : default_erase());
370     }
371 
372     if (DISABLED(tty_settings->c_cc[VINTR]) || my_intr >= 0) {
373 	tty_settings->c_cc[VINTR] = UChar((my_intr >= 0)
374 					  ? my_intr
375 					  : CINTR);
376     }
377 
378     if (DISABLED(tty_settings->c_cc[VKILL]) || my_kill >= 0) {
379 	tty_settings->c_cc[VKILL] = UChar((my_kill >= 0)
380 					  ? my_kill
381 					  : CKILL);
382     }
383 }
384 
385 /*
386  * Set up various conversions in the TTY parameter, including parity, tabs,
387  * returns, echo, and case, according to the termcap entry.
388  */
389 void
390 set_conversions(TTY * tty_settings)
391 {
392 #ifdef ONLCR
393     tty_settings->c_oflag |= ONLCR;
394 #endif
395     tty_settings->c_iflag |= ICRNL;
396     tty_settings->c_lflag |= ECHO;
397 #ifdef OXTABS
398     tty_settings->c_oflag |= OXTABS;
399 #endif /* OXTABS */
400 
401     /* test used to be tgetflag("NL") */
402     if (VALID_STRING(newline) && newline[0] == '\n' && !newline[1]) {
403 	/* Newline, not linefeed. */
404 #ifdef ONLCR
405 	tty_settings->c_oflag &= ~((unsigned) ONLCR);
406 #endif
407 	tty_settings->c_iflag &= ~((unsigned) ICRNL);
408     }
409 #ifdef OXTABS
410     /* test used to be tgetflag("pt") */
411     if (VALID_STRING(set_tab) && VALID_STRING(clear_all_tabs))
412 	tty_settings->c_oflag &= ~OXTABS;
413 #endif /* OXTABS */
414     tty_settings->c_lflag |= (ECHOE | ECHOK);
415 }
416 
417 static bool
418 sent_string(const char *s)
419 {
420     bool sent = FALSE;
421     if (VALID_STRING(s)) {
422 	tputs(s, 0, out_char);
423 	sent = TRUE;
424     }
425     return sent;
426 }
427 
428 static bool
429 to_left_margin(void)
430 {
431     if (VALID_STRING(carriage_return)) {
432 	sent_string(carriage_return);
433     } else {
434 	out_char('\r');
435     }
436     return TRUE;
437 }
438 
439 /*
440  * Set the hardware tabs on the terminal, using the 'ct' (clear all tabs),
441  * 'st' (set one tab) and 'ch' (horizontal cursor addressing) capabilities.
442  * This is done before 'if' and 'is', so they can recover in case of error.
443  *
444  * Return TRUE if we set any tab stops, FALSE if not.
445  */
446 static bool
447 reset_tabstops(int wide)
448 {
449     if ((init_tabs != 8)
450 	&& VALID_NUMERIC(init_tabs)
451 	&& VALID_STRING(set_tab)
452 	&& VALID_STRING(clear_all_tabs)) {
453 	int c;
454 
455 	to_left_margin();
456 	tputs(clear_all_tabs, 0, out_char);
457 	if (init_tabs > 1) {
458 	    if (init_tabs > wide)
459 		init_tabs = (short) wide;
460 	    for (c = init_tabs; c < wide; c += init_tabs) {
461 		fprintf(my_file, "%*s", init_tabs, " ");
462 		tputs(set_tab, 0, out_char);
463 	    }
464 	    to_left_margin();
465 	}
466 	return (TRUE);
467     }
468     return (FALSE);
469 }
470 
471 /* Output startup string. */
472 bool
473 send_init_strings(int fd GCC_UNUSED, TTY * old_settings)
474 {
475     int i;
476     bool need_flush = FALSE;
477 
478     (void) old_settings;
479 #ifdef TAB3
480     if (old_settings != 0 &&
481 	old_settings->c_oflag & (TAB3 | ONLCR | OCRNL | ONLRET)) {
482 	old_settings->c_oflag &= (TAB3 | ONLCR | OCRNL | ONLRET);
483 	SET_TTY(fd, old_settings);
484     }
485 #endif
486     if (use_reset || use_init) {
487 	if (VALID_STRING(init_prog)) {
488 	    IGNORE_RC(system(init_prog));
489 	}
490 
491 	need_flush |= sent_string((use_reset && (reset_1string != 0))
492 				  ? reset_1string
493 				  : init_1string);
494 
495 	need_flush |= sent_string((use_reset && (reset_2string != 0))
496 				  ? reset_2string
497 				  : init_2string);
498 
499 	if (VALID_STRING(clear_margins)) {
500 	    need_flush |= sent_string(clear_margins);
501 	} else
502 #if defined(set_lr_margin)
503 	if (VALID_STRING(set_lr_margin)) {
504 	    need_flush |= sent_string(TPARM_2(set_lr_margin, 0,
505 					      columns - 1));
506 	} else
507 #endif
508 #if defined(set_left_margin_parm) && defined(set_right_margin_parm)
509 	    if (VALID_STRING(set_left_margin_parm)
510 		&& VALID_STRING(set_right_margin_parm)) {
511 	    need_flush |= sent_string(TPARM_1(set_left_margin_parm, 0));
512 	    need_flush |= sent_string(TPARM_1(set_right_margin_parm,
513 					      columns - 1));
514 	} else
515 #endif
516 	    if (VALID_STRING(set_left_margin)
517 		&& VALID_STRING(set_right_margin)) {
518 	    need_flush |= to_left_margin();
519 	    need_flush |= sent_string(set_left_margin);
520 	    if (VALID_STRING(parm_right_cursor)) {
521 		need_flush |= sent_string(TPARM_1(parm_right_cursor,
522 						  columns - 1));
523 	    } else {
524 		for (i = 0; i < columns - 1; i++) {
525 		    out_char(' ');
526 		    need_flush = TRUE;
527 		}
528 	    }
529 	    need_flush |= sent_string(set_right_margin);
530 	    need_flush |= to_left_margin();
531 	}
532 
533 	need_flush |= reset_tabstops(columns);
534 
535 	need_flush |= cat_file((use_reset && reset_file) ? reset_file : init_file);
536 
537 	need_flush |= sent_string((use_reset && (reset_3string != 0))
538 				  ? reset_3string
539 				  : init_3string);
540     }
541 
542     return need_flush;
543 }
544 
545 /*
546  * Tell the user if a control key has been changed from the default value.
547  */
548 static void
549 show_tty_change(TTY * old_settings,
550 		TTY * new_settings,
551 		const char *name,
552 		int which,
553 		unsigned def)
554 {
555     unsigned older, newer;
556     char *p;
557 
558     newer = new_settings->c_cc[which];
559     older = old_settings->c_cc[which];
560 
561     if (older == newer && older == def)
562 	return;
563 
564     (void) fprintf(stderr, "%s %s ", name, older == newer ? "is" : "set to");
565 
566     if (DISABLED(newer)) {
567 	(void) fprintf(stderr, "undef.\n");
568 	/*
569 	 * Check 'delete' before 'backspace', since the key_backspace value
570 	 * is ambiguous.
571 	 */
572     } else if (newer == 0177) {
573 	(void) fprintf(stderr, "delete.\n");
574     } else if ((p = key_backspace) != 0
575 	       && newer == (unsigned char) p[0]
576 	       && p[1] == '\0') {
577 	(void) fprintf(stderr, "backspace.\n");
578     } else if (newer < 040) {
579 	newer ^= 0100;
580 	(void) fprintf(stderr, "control-%c (^%c).\n", UChar(newer), UChar(newer));
581     } else
582 	(void) fprintf(stderr, "%c.\n", UChar(newer));
583 }
584 
585 /**************************************************************************
586  * Miscellaneous.
587  **************************************************************************/
588 
589 void
590 reset_start(FILE *fp, bool is_reset, bool is_init)
591 {
592     my_file = fp;
593     use_reset = is_reset;
594     use_init = is_init;
595 }
596 
597 void
598 reset_flush(void)
599 {
600     if (my_file != 0)
601 	fflush(my_file);
602 }
603 
604 void
605 print_tty_chars(TTY * old_settings, TTY * new_settings)
606 {
607     show_tty_change(old_settings, new_settings, "Erase", VERASE, CERASE);
608     show_tty_change(old_settings, new_settings, "Kill", VKILL, CKILL);
609     show_tty_change(old_settings, new_settings, "Interrupt", VINTR, CINTR);
610 }
611 
612 #if HAVE_SIZECHANGE
613 /*
614  * Set window size if not set already, but update our copy of the values if the
615  * size was set.
616  */
617 void
618 set_window_size(int fd, short *high, short *wide)
619 {
620     STRUCT_WINSIZE win;
621     (void) ioctl(fd, IOCTL_GET_WINSIZE, &win);
622     if (WINSIZE_ROWS(win) == 0 &&
623 	WINSIZE_COLS(win) == 0) {
624 	if (*high > 0 && *wide > 0) {
625 	    WINSIZE_ROWS(win) = (unsigned short) *high;
626 	    WINSIZE_COLS(win) = (unsigned short) *wide;
627 	    (void) ioctl(fd, IOCTL_SET_WINSIZE, &win);
628 	}
629     } else if (WINSIZE_ROWS(win) > 0 &&
630 	       WINSIZE_COLS(win) > 0) {
631 	*high = (short) WINSIZE_ROWS(win);
632 	*wide = (short) WINSIZE_COLS(win);
633     }
634 }
635 #endif
636