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
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 = 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)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
default_erase(void)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
set_control_chars(TTY * tty_settings,int my_erase,int my_intr,int my_kill)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
set_conversions(TTY * tty_settings)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
sent_string(const char * s)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
to_left_margin(void)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
reset_tabstops(int wide)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
send_init_strings(int fd GCC_UNUSED,TTY * old_settings)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
show_tty_change(TTY * old_settings,TTY * new_settings,const char * name,int which,unsigned def)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
reset_start(FILE * fp,bool is_reset,bool is_init)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
reset_flush(void)598 reset_flush(void)
599 {
600 if (my_file != 0)
601 fflush(my_file);
602 }
603
604 void
print_tty_chars(TTY * old_settings,TTY * new_settings)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
set_window_size(int fd,short * high,short * wide)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