1 /****************************************************************************
2 * Copyright 2019-2021,2023 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 is 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 1.1 2023/10/17 09:52:10 nicm 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 GCC_NORETURN void
failed(const char * msg)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
cat_file(char * file)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 = safe_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
out_char(int c)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
reset_tty_settings(int fd,TTY * tty_settings,int noset)196 reset_tty_settings(int fd, TTY * tty_settings, int noset)
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(VERASE2) && defined(CERASE2)
207 reset_char(VERASE2, CERASE2);
208 #endif
209 #if defined(VFLUSH) && defined(CFLUSH)
210 reset_char(VFLUSH, CFLUSH);
211 #endif
212 reset_char(VINTR, CINTR);
213 reset_char(VKILL, CKILL);
214 #if defined(VLNEXT) && defined(CLNEXT)
215 reset_char(VLNEXT, CLNEXT);
216 #endif
217 reset_char(VQUIT, CQUIT);
218 #if defined(VREPRINT) && defined(CRPRNT)
219 reset_char(VREPRINT, CRPRNT);
220 #endif
221 #if defined(VSTART) && defined(CSTART)
222 reset_char(VSTART, CSTART);
223 #endif
224 #if defined(VSTOP) && defined(CSTOP)
225 reset_char(VSTOP, CSTOP);
226 #endif
227 #if defined(VSUSP) && defined(CSUSP)
228 reset_char(VSUSP, CSUSP);
229 #endif
230 #if defined(VWERASE) && defined(CWERASE)
231 reset_char(VWERASE, CWERASE);
232 #endif
233
234 tty_settings->c_iflag &= ~((unsigned) (IGNBRK
235 | PARMRK
236 | INPCK
237 | ISTRIP
238 | INLCR
239 | IGNCR
240 #ifdef IUCLC
241 | IUCLC
242 #endif
243 #ifdef IXANY
244 | IXANY
245 #endif
246 | IXOFF));
247
248 tty_settings->c_iflag |= (BRKINT
249 | IGNPAR
250 | ICRNL
251 | IXON
252 #ifdef IMAXBEL
253 | IMAXBEL
254 #endif
255 );
256
257 tty_settings->c_oflag &= ~((unsigned) (0
258 #ifdef OLCUC
259 | OLCUC
260 #endif
261 #ifdef OCRNL
262 | OCRNL
263 #endif
264 #ifdef ONOCR
265 | ONOCR
266 #endif
267 #ifdef ONLRET
268 | ONLRET
269 #endif
270 #ifdef OFILL
271 | OFILL
272 #endif
273 #ifdef OFDEL
274 | OFDEL
275 #endif
276 #ifdef NLDLY
277 | NLDLY
278 #endif
279 #ifdef CRDLY
280 | CRDLY
281 #endif
282 #ifdef TABDLY
283 | TABDLY
284 #endif
285 #ifdef BSDLY
286 | BSDLY
287 #endif
288 #ifdef VTDLY
289 | VTDLY
290 #endif
291 #ifdef FFDLY
292 | FFDLY
293 #endif
294 ));
295
296 tty_settings->c_oflag |= (OPOST
297 #ifdef ONLCR
298 | ONLCR
299 #endif
300 );
301
302 tty_settings->c_cflag &= ~((unsigned) (CSIZE
303 | CSTOPB
304 | PARENB
305 | PARODD
306 | CLOCAL));
307 tty_settings->c_cflag |= (CS8 | CREAD);
308 tty_settings->c_lflag &= ~((unsigned) (ECHONL
309 | NOFLSH
310 #ifdef TOSTOP
311 | TOSTOP
312 #endif
313 #ifdef ECHOPTR
314 | ECHOPRT
315 #endif
316 #ifdef XCASE
317 | XCASE
318 #endif
319 ));
320
321 tty_settings->c_lflag |= (ISIG
322 | ICANON
323 | ECHO
324 | ECHOE
325 | ECHOK
326 #ifdef ECHOCTL
327 | ECHOCTL
328 #endif
329 #ifdef ECHOKE
330 | ECHOKE
331 #endif
332 );
333 #endif
334
335 if (!noset) {
336 SET_TTY(fd, tty_settings);
337 }
338 }
339
340 /*
341 * Returns a "good" value for the erase character. This is loosely based on
342 * the BSD4.4 logic.
343 */
344 static int
default_erase(void)345 default_erase(void)
346 {
347 int result;
348
349 if (over_strike
350 && VALID_STRING(key_backspace)
351 && strlen(key_backspace) == 1) {
352 result = key_backspace[0];
353 } else {
354 result = CERASE;
355 }
356
357 return result;
358 }
359
360 /*
361 * Update the values of the erase, interrupt, and kill characters in the TTY
362 * parameter.
363 *
364 * SVr4 tset (e.g., Solaris 2.5) only modifies the intr, quit or erase
365 * characters if they're unset, or if we specify them as options. This differs
366 * from BSD 4.4 tset, which always sets erase.
367 */
368 void
set_control_chars(TTY * tty_settings,int my_erase,int my_intr,int my_kill)369 set_control_chars(TTY * tty_settings, int my_erase, int my_intr, int my_kill)
370 {
371 #if defined(EXP_WIN32_DRIVER)
372 /* noop */
373 (void) tty_settings;
374 (void) my_erase;
375 (void) my_intr;
376 (void) my_kill;
377 #else
378 if (DISABLED(tty_settings->c_cc[VERASE]) || my_erase >= 0) {
379 tty_settings->c_cc[VERASE] = UChar((my_erase >= 0)
380 ? my_erase
381 : default_erase());
382 }
383
384 if (DISABLED(tty_settings->c_cc[VINTR]) || my_intr >= 0) {
385 tty_settings->c_cc[VINTR] = UChar((my_intr >= 0)
386 ? my_intr
387 : CINTR);
388 }
389
390 if (DISABLED(tty_settings->c_cc[VKILL]) || my_kill >= 0) {
391 tty_settings->c_cc[VKILL] = UChar((my_kill >= 0)
392 ? my_kill
393 : CKILL);
394 }
395 #endif
396 }
397
398 /*
399 * Set up various conversions in the TTY parameter, including parity, tabs,
400 * returns, echo, and case, according to the termcap entry.
401 */
402 void
set_conversions(TTY * tty_settings)403 set_conversions(TTY * tty_settings)
404 {
405 #if defined(EXP_WIN32_DRIVER)
406 /* FIXME */
407 #else
408 #ifdef ONLCR
409 tty_settings->c_oflag |= ONLCR;
410 #endif
411 tty_settings->c_iflag |= ICRNL;
412 tty_settings->c_lflag |= ECHO;
413 #ifdef OXTABS
414 tty_settings->c_oflag |= OXTABS;
415 #endif /* OXTABS */
416
417 /* test used to be tgetflag("NL") */
418 if (VALID_STRING(newline) && newline[0] == '\n' && !newline[1]) {
419 /* Newline, not linefeed. */
420 #ifdef ONLCR
421 tty_settings->c_oflag &= ~((unsigned) ONLCR);
422 #endif
423 tty_settings->c_iflag &= ~((unsigned) ICRNL);
424 }
425 #ifdef OXTABS
426 /* test used to be tgetflag("pt") */
427 if (VALID_STRING(set_tab) && VALID_STRING(clear_all_tabs))
428 tty_settings->c_oflag &= ~OXTABS;
429 #endif /* OXTABS */
430 tty_settings->c_lflag |= (ECHOE | ECHOK);
431 #endif
432 }
433
434 static bool
sent_string(const char * s)435 sent_string(const char *s)
436 {
437 bool sent = FALSE;
438 if (VALID_STRING(s)) {
439 tputs(s, 0, out_char);
440 sent = TRUE;
441 }
442 return sent;
443 }
444
445 static bool
to_left_margin(void)446 to_left_margin(void)
447 {
448 if (VALID_STRING(carriage_return)) {
449 sent_string(carriage_return);
450 } else {
451 out_char('\r');
452 }
453 return TRUE;
454 }
455
456 /*
457 * Set the hardware tabs on the terminal, using the 'ct' (clear all tabs),
458 * 'st' (set one tab) and 'ch' (horizontal cursor addressing) capabilities.
459 * This is done before 'if' and 'is', so they can recover in case of error.
460 *
461 * Return TRUE if we set any tab stops, FALSE if not.
462 */
463 static bool
reset_tabstops(int wide)464 reset_tabstops(int wide)
465 {
466 if ((init_tabs != 8)
467 && VALID_NUMERIC(init_tabs)
468 && VALID_STRING(set_tab)
469 && VALID_STRING(clear_all_tabs)) {
470 int c;
471
472 to_left_margin();
473 tputs(clear_all_tabs, 0, out_char);
474 if (init_tabs > 1) {
475 if (init_tabs > wide)
476 init_tabs = (short) wide;
477 for (c = init_tabs; c < wide; c += init_tabs) {
478 fprintf(my_file, "%*s", init_tabs, " ");
479 tputs(set_tab, 0, out_char);
480 }
481 to_left_margin();
482 }
483 return (TRUE);
484 }
485 return (FALSE);
486 }
487
488 /* Output startup string. */
489 bool
send_init_strings(int fd GCC_UNUSED,TTY * old_settings)490 send_init_strings(int fd GCC_UNUSED, TTY * old_settings)
491 {
492 int i;
493 bool need_flush = FALSE;
494
495 (void) old_settings;
496 #ifdef TAB3
497 if (old_settings != 0 &&
498 old_settings->c_oflag & (TAB3 | ONLCR | OCRNL | ONLRET)) {
499 old_settings->c_oflag &= (TAB3 | ONLCR | OCRNL | ONLRET);
500 SET_TTY(fd, old_settings);
501 }
502 #endif
503 if (use_reset || use_init) {
504 if (VALID_STRING(init_prog)) {
505 IGNORE_RC(system(init_prog));
506 }
507
508 need_flush |= sent_string((use_reset && (reset_1string != 0))
509 ? reset_1string
510 : init_1string);
511
512 need_flush |= sent_string((use_reset && (reset_2string != 0))
513 ? reset_2string
514 : init_2string);
515
516 if (VALID_STRING(clear_margins)) {
517 need_flush |= sent_string(clear_margins);
518 } else
519 #if defined(set_lr_margin)
520 if (VALID_STRING(set_lr_margin)) {
521 need_flush |= sent_string(TIPARM_2(set_lr_margin, 0, columns - 1));
522 } else
523 #endif
524 #if defined(set_left_margin_parm) && defined(set_right_margin_parm)
525 if (VALID_STRING(set_left_margin_parm)
526 && VALID_STRING(set_right_margin_parm)) {
527 need_flush |= sent_string(TIPARM_1(set_left_margin_parm, 0));
528 need_flush |= sent_string(TIPARM_1(set_right_margin_parm,
529 columns - 1));
530 } else
531 #endif
532 if (VALID_STRING(set_left_margin)
533 && VALID_STRING(set_right_margin)) {
534 need_flush |= to_left_margin();
535 need_flush |= sent_string(set_left_margin);
536 if (VALID_STRING(parm_right_cursor)) {
537 need_flush |= sent_string(TIPARM_1(parm_right_cursor,
538 columns - 1));
539 } else {
540 for (i = 0; i < columns - 1; i++) {
541 out_char(' ');
542 need_flush = TRUE;
543 }
544 }
545 need_flush |= sent_string(set_right_margin);
546 need_flush |= to_left_margin();
547 }
548
549 need_flush |= reset_tabstops(columns);
550
551 need_flush |= cat_file((use_reset && reset_file) ? reset_file : init_file);
552
553 need_flush |= sent_string((use_reset && (reset_3string != 0))
554 ? reset_3string
555 : init_3string);
556 }
557
558 return need_flush;
559 }
560
561 /*
562 * Tell the user if a control key has been changed from the default value.
563 */
564 static void
show_tty_change(TTY * old_settings,TTY * new_settings,const char * name,int which,unsigned def)565 show_tty_change(TTY * old_settings,
566 TTY * new_settings,
567 const char *name,
568 int which,
569 unsigned def)
570 {
571 unsigned older = 0, newer = 0;
572 char *p;
573
574 #if defined(EXP_WIN32_DRIVER)
575 /* noop */
576 (void) old_settings;
577 (void) new_settings;
578 (void) name;
579 (void) which;
580 (void) def;
581 #else
582 newer = new_settings->c_cc[which];
583 older = old_settings->c_cc[which];
584
585 if (older == newer && older == def)
586 return;
587 #endif
588 (void) fprintf(stderr, "%s %s ", name, older == newer ? "is" : "set to");
589
590 if (DISABLED(newer)) {
591 (void) fprintf(stderr, "undef.\n");
592 /*
593 * Check 'delete' before 'backspace', since the key_backspace value
594 * is ambiguous.
595 */
596 } else if (newer == 0177) {
597 (void) fprintf(stderr, "delete.\n");
598 } else if ((p = key_backspace) != 0
599 && newer == (unsigned char) p[0]
600 && p[1] == '\0') {
601 (void) fprintf(stderr, "backspace.\n");
602 } else if (newer < 040) {
603 newer ^= 0100;
604 (void) fprintf(stderr, "control-%c (^%c).\n", UChar(newer), UChar(newer));
605 } else
606 (void) fprintf(stderr, "%c.\n", UChar(newer));
607 }
608
609 /**************************************************************************
610 * Miscellaneous.
611 **************************************************************************/
612
613 void
reset_start(FILE * fp,bool is_reset,bool is_init)614 reset_start(FILE *fp, bool is_reset, bool is_init)
615 {
616 my_file = fp;
617 use_reset = is_reset;
618 use_init = is_init;
619 }
620
621 void
reset_flush(void)622 reset_flush(void)
623 {
624 if (my_file != 0)
625 fflush(my_file);
626 }
627
628 void
print_tty_chars(TTY * old_settings,TTY * new_settings)629 print_tty_chars(TTY * old_settings, TTY * new_settings)
630 {
631 #if defined(EXP_WIN32_DRIVER)
632 /* noop */
633 #else
634 show_tty_change(old_settings, new_settings, "Erase", VERASE, CERASE);
635 show_tty_change(old_settings, new_settings, "Kill", VKILL, CKILL);
636 show_tty_change(old_settings, new_settings, "Interrupt", VINTR, CINTR);
637 #endif
638 }
639
640 #if HAVE_SIZECHANGE
641 /*
642 * Set window size if not set already, but update our copy of the values if the
643 * size was set.
644 */
645 void
set_window_size(int fd,short * high,short * wide)646 set_window_size(int fd, short *high, short *wide)
647 {
648 STRUCT_WINSIZE win;
649 (void) ioctl(fd, IOCTL_GET_WINSIZE, &win);
650 if (WINSIZE_ROWS(win) == 0 &&
651 WINSIZE_COLS(win) == 0) {
652 if (*high > 0 && *wide > 0) {
653 WINSIZE_ROWS(win) = (unsigned short) *high;
654 WINSIZE_COLS(win) = (unsigned short) *wide;
655 (void) ioctl(fd, IOCTL_SET_WINSIZE, &win);
656 }
657 } else if (WINSIZE_ROWS(win) > 0 &&
658 WINSIZE_COLS(win) > 0) {
659 *high = (short) WINSIZE_ROWS(win);
660 *wide = (short) WINSIZE_COLS(win);
661 }
662 }
663 #endif
664