1 /****************************************************************************
2 * Copyright 2020-2022,2023 Thomas E. Dickey *
3 * Copyright 2008-2016,2017 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 2008 *
32 ****************************************************************************/
33
34 /*
35 * tabs.c -- set terminal hard-tabstops
36 */
37
38 #define USE_LIBTINFO
39 #include <progs.priv.h>
40 #include <tty_settings.h>
41
42 MODULE_ID("$Id: tabs.c,v 1.53 2023/11/04 20:46:09 tom Exp $")
43
44 static GCC_NORETURN void usage(void);
45
46 const char *_nc_progname;
47 static int max_cols;
48
49 static void
failed(const char * s)50 failed(const char *s)
51 {
52 perror(s);
53 ExitProgram(EXIT_FAILURE);
54 }
55
56 static int
putch(int c)57 putch(int c)
58 {
59 return putchar(c);
60 }
61
62 static char *
skip_csi(char * value)63 skip_csi(char *value)
64 {
65 if (UChar(*value) == 0x9b)
66 ++value;
67 else if (!strncmp(value, "\033[", 2))
68 value += 2;
69 return value;
70 }
71
72 /*
73 * If the terminal uses ANSI clear_all_tabs, then it is not necessary to first
74 * move to the left margin before clearing tabs.
75 */
76 static bool
ansi_clear_tabs(void)77 ansi_clear_tabs(void)
78 {
79 bool result = FALSE;
80 if (VALID_STRING(clear_all_tabs)) {
81 char *param = skip_csi(clear_all_tabs);
82 if (!strcmp(param, "3g"))
83 result = TRUE;
84 }
85 return result;
86 }
87
88 static void
do_tabs(int * tab_list)89 do_tabs(int *tab_list)
90 {
91 int last = 1;
92 int stop;
93 bool first = TRUE;
94
95 while ((stop = *tab_list++) > 0) {
96 if (first) {
97 first = FALSE;
98 putchar('\r');
99 }
100 if (last < stop) {
101 while (last++ < stop) {
102 if (last > max_cols)
103 break;
104 putchar(' ');
105 }
106 }
107 if (stop <= max_cols) {
108 tputs(set_tab, 1, putch);
109 last = stop;
110 } else {
111 break;
112 }
113 }
114 putchar('\r');
115 }
116
117 /*
118 * Decode a list of tab-stops from a string, returning an array of integers.
119 * If the margin is positive (because the terminal does not support margins),
120 * work around this by adding the margin to the decoded values.
121 */
122 static int *
decode_tabs(const char * tab_list,int margin)123 decode_tabs(const char *tab_list, int margin)
124 {
125 int *result = typeCalloc(int, strlen(tab_list) + (unsigned) max_cols);
126 int n = 0;
127 int value = 0;
128 int prior = 0;
129 int ch;
130
131 if (result == NULL)
132 failed("decode_tabs");
133
134 if (margin < 0)
135 margin = 0;
136
137 while ((ch = *tab_list++) != '\0') {
138 if (isdigit(UChar(ch))) {
139 value *= 10;
140 value += (ch - '0');
141 if (value > max_cols)
142 value = max_cols;
143 } else if (ch == ',') {
144 result[n] = value + prior + margin;
145 if (n > 0 && result[n] <= result[n - 1]) {
146 fprintf(stderr,
147 "%s: tab-stops are not in increasing order: %d %d\n",
148 _nc_progname, value, result[n - 1]);
149 free(result);
150 result = 0;
151 break;
152 }
153 ++n;
154 value = 0;
155 prior = 0;
156 } else if (ch == '+') {
157 if (n)
158 prior = result[n - 1];
159 }
160 }
161
162 if (result != 0) {
163 /*
164 * If there is only one value, then it is an option such as "-8".
165 */
166 if ((n == 0) && (value > 0)) {
167 int step = value;
168 value = 1;
169 while (n < max_cols - 1) {
170 result[n++] = value + margin;
171 value += step;
172 }
173 }
174
175 /*
176 * Add the last value, if any.
177 */
178 result[n++] = value + prior + margin;
179 result[n] = 0;
180 }
181
182 return result;
183 }
184
185 static void
print_ruler(const int * const tab_list,const char * new_line)186 print_ruler(const int *const tab_list, const char *new_line)
187 {
188 int last = 0;
189 int n;
190
191 /* first print a readable ruler */
192 for (n = 0; n < max_cols; n += 10) {
193 int ch = 1 + (n / 10);
194 char buffer[20];
195 _nc_SPRINTF(buffer, _nc_SLIMIT(sizeof(buffer))
196 "----+----%c",
197 ((ch < 10)
198 ? (ch + '0')
199 : (ch + 'A' - 10)));
200 printf("%.*s", ((max_cols - n) > 10) ? 10 : (max_cols - n), buffer);
201 }
202 printf("%s", new_line);
203
204 /* now, print '*' for each stop */
205 for (n = 0, last = 0; (tab_list[n] > 0) && (last < max_cols); ++n) {
206 int stop = tab_list[n];
207
208 while (++last < stop) {
209 if (last <= max_cols) {
210 putchar('-');
211 } else {
212 break;
213 }
214 }
215 if (last <= max_cols) {
216 putchar('*');
217 last = stop;
218 } else {
219 break;
220 }
221 }
222 while (++last <= max_cols)
223 putchar('-');
224 printf("%s", new_line);
225 }
226
227 /*
228 * Write an '*' on each tabstop, to demonstrate whether it lines up with the
229 * ruler.
230 */
231 static void
write_tabs(int * tab_list,const char * new_line)232 write_tabs(int *tab_list, const char *new_line)
233 {
234 int stop;
235
236 while ((stop = *tab_list++) > 0 && stop <= max_cols) {
237 fputs((stop == 1) ? "*" : "\t*", stdout);
238 };
239 /* also show a tab _past_ the stops */
240 if (stop < max_cols)
241 fputs("\t+", stdout);
242 fputs(new_line, stdout);
243 }
244
245 /*
246 * Trim leading/trailing blanks, as well as blanks after a comma.
247 * Convert embedded blanks to commas.
248 */
249 static char *
trimmed_tab_list(const char * source)250 trimmed_tab_list(const char *source)
251 {
252 char *result = strdup(source);
253 if (result != 0) {
254 int j, k, last;
255
256 for (j = k = last = 0; result[j] != 0; ++j) {
257 int ch = UChar(result[j]);
258 if (isspace(ch)) {
259 if (last == '\0') {
260 continue;
261 } else if (isdigit(last) || last == ',') {
262 ch = ',';
263 }
264 } else if (ch == ',') {
265 ;
266 } else {
267 if (last == ',')
268 result[k++] = (char) last;
269 result[k++] = (char) ch;
270 }
271 last = ch;
272 }
273 result[k] = '\0';
274 }
275 return result;
276 }
277
278 static bool
comma_is_needed(const char * source)279 comma_is_needed(const char *source)
280 {
281 bool result = FALSE;
282
283 if (source != 0) {
284 size_t len = strlen(source);
285 if (len != 0)
286 result = (source[len - 1] != ',');
287 } else {
288 result = FALSE;
289 }
290 return result;
291 }
292
293 /*
294 * Add a command-line parameter to the tab-list. It can be blank- or comma-
295 * separated (or a mixture). For simplicity, empty tabs are ignored, e.g.,
296 * tabs 1,,6,11
297 * tabs 1,6,11
298 * are treated the same.
299 */
300 static const char *
add_to_tab_list(char ** append,const char * value)301 add_to_tab_list(char **append, const char *value)
302 {
303 char *result = *append;
304 char *copied = trimmed_tab_list(value);
305
306 if (copied != 0 && *copied != '\0') {
307 const char *comma = ",";
308 size_t need = 1 + strlen(copied);
309
310 if (*copied == ',')
311 comma = "";
312 else if (!comma_is_needed(*append))
313 comma = "";
314
315 need += strlen(comma);
316 if (*append != 0)
317 need += strlen(*append);
318
319 result = malloc(need);
320 if (result == 0)
321 failed("add_to_tab_list");
322
323 *result = '\0';
324 if (*append != 0) {
325 _nc_STRCPY(result, *append, need);
326 free(*append);
327 }
328 _nc_STRCAT(result, comma, need);
329 _nc_STRCAT(result, copied, need);
330
331 *append = result;
332 }
333 free(copied);
334 return result;
335 }
336
337 /*
338 * If the terminal supports it, (re)set the left margin and return true.
339 * Otherwise, return false.
340 */
341 static bool
do_set_margin(int margin,bool no_op)342 do_set_margin(int margin, bool no_op)
343 {
344 bool result = FALSE;
345
346 if (margin == 0) { /* 0 is special case for resetting */
347 if (VALID_STRING(clear_margins)) {
348 result = TRUE;
349 if (!no_op)
350 tputs(clear_margins, 1, putch);
351 }
352 } else if (margin-- < 0) { /* margin will be 0-based from here on */
353 result = TRUE;
354 } else if (VALID_STRING(set_left_margin)) {
355 result = TRUE;
356 if (!no_op) {
357 /*
358 * assuming we're on the first column of the line, move the cursor
359 * to the column at which we will set a margin.
360 */
361 if (VALID_STRING(column_address)) {
362 tputs(TIPARM_1(column_address, margin), 1, putch);
363 } else if (margin >= 1) {
364 if (VALID_STRING(parm_right_cursor)) {
365 tputs(TIPARM_1(parm_right_cursor, margin), 1, putch);
366 } else {
367 while (margin-- > 0)
368 putch(' ');
369 }
370 }
371 tputs(set_left_margin, 1, putch);
372 }
373 }
374 #if defined(set_left_margin_parm) && defined(set_right_margin_parm)
375 else if (VALID_STRING(set_left_margin_parm)) {
376 result = TRUE;
377 if (!no_op) {
378 if (VALID_STRING(set_right_margin_parm)) {
379 tputs(TIPARM_1(set_left_margin_parm, margin), 1, putch);
380 } else {
381 tputs(TIPARM_2(set_left_margin_parm, margin, max_cols), 1, putch);
382 }
383 }
384 }
385 #endif
386 #if defined(set_lr_margin)
387 else if (VALID_STRING(set_lr_margin)) {
388 result = TRUE;
389 if (!no_op) {
390 tputs(TIPARM_2(set_lr_margin, margin, max_cols), 1, putch);
391 }
392 }
393 #endif
394 return result;
395 }
396
397 /*
398 * Check for illegal characters in the tab-list.
399 */
400 static bool
legal_tab_list(const char * tab_list)401 legal_tab_list(const char *tab_list)
402 {
403 bool result = TRUE;
404
405 if (tab_list != 0 && *tab_list != '\0') {
406 if (comma_is_needed(tab_list)) {
407 int n;
408
409 for (n = 0; tab_list[n] != '\0'; ++n) {
410 int ch = UChar(tab_list[n]);
411
412 if (!(isdigit(ch) || ch == ',' || ch == '+')) {
413 fprintf(stderr,
414 "%s: unexpected character found '%c'\n",
415 _nc_progname, ch);
416 result = FALSE;
417 break;
418 }
419 }
420 } else {
421 fprintf(stderr, "%s: trailing comma found '%s'\n", _nc_progname, tab_list);
422 result = FALSE;
423 }
424 } else {
425 /* if no list given, default to "tabs -8" */
426 }
427 return result;
428 }
429
430 static char *
skip_list(char * value)431 skip_list(char *value)
432 {
433 while (*value != '\0' &&
434 (isdigit(UChar(*value)) ||
435 isspace(UChar(*value)) ||
436 strchr("+,", UChar(*value)) != 0)) {
437 ++value;
438 }
439 return value;
440 }
441
442 static void
usage(void)443 usage(void)
444 {
445 #define DATA(s) s "\n"
446 static const char msg[] =
447 {
448 DATA("Usage: tabs [options] [tabstop-list]")
449 DATA("")
450 DATA("Options:")
451 DATA(" -0 reset tabs")
452 DATA(" -8 set tabs to standard interval")
453 DATA(" -a Assembler, IBM S/370, first format")
454 DATA(" -a2 Assembler, IBM S/370, second format")
455 DATA(" -c COBOL, normal format")
456 DATA(" -c2 COBOL compact format")
457 DATA(" -c3 COBOL compact format extended")
458 DATA(" -d debug (show ruler with expected/actual tab positions)")
459 DATA(" -f FORTRAN")
460 DATA(" -n no-op (do not modify terminal settings)")
461 DATA(" -p PL/I")
462 DATA(" -s SNOBOL")
463 DATA(" -u UNIVAC 1100 Assembler")
464 DATA(" -T name use terminal type 'name'")
465 DATA(" -V print version")
466 DATA("")
467 DATA("A tabstop-list is an ordered list of column numbers, e.g., 1,11,21")
468 DATA("or 1,+10,+10 which is the same.")
469 };
470 #undef DATA
471
472 fflush(stdout);
473 fputs(msg, stderr);
474 ExitProgram(EXIT_FAILURE);
475 }
476
477 int
main(int argc,char * argv[])478 main(int argc, char *argv[])
479 {
480 int rc = EXIT_FAILURE;
481 bool debug = FALSE;
482 bool no_op = FALSE;
483 bool change_tty = FALSE;
484 int n, ch;
485 NCURSES_CONST char *term_name = 0;
486 char *append = 0;
487 const char *tab_list = 0;
488 const char *new_line = "\n";
489 int margin = -1;
490 TTY tty_settings;
491 int fd;
492
493 _nc_progname = _nc_rootname(argv[0]);
494
495 if ((term_name = getenv("TERM")) == 0)
496 term_name = "ansi+tabs";
497
498 /* cannot use getopt, since some options are two-character */
499 for (n = 1; n < argc; ++n) {
500 char *option = argv[n];
501 switch (option[0]) {
502 case '-':
503 while ((ch = *++option) != '\0') {
504 switch (ch) {
505 case 'a':
506 switch (*++option) {
507 default:
508 case '\0':
509 tab_list = "1,10,16,36,72";
510 option--;
511 /* Assembler, IBM S/370, first format */
512 break;
513 case '2':
514 tab_list = "1,10,16,40,72";
515 /* Assembler, IBM S/370, second format */
516 break;
517 }
518 break;
519 case 'c':
520 switch (*++option) {
521 default:
522 case '\0':
523 tab_list = "1,8,12,16,20,55";
524 option--;
525 /* COBOL, normal format */
526 break;
527 case '2':
528 tab_list = "1,6,10,14,49";
529 /* COBOL compact format */
530 break;
531 case '3':
532 tab_list = "1,6,10,14,18,22,26,30,34,38,42,46,50,54,58,62,67";
533 /* COBOL compact format extended */
534 break;
535 }
536 break;
537 case 'd': /* ncurses extension */
538 debug = TRUE;
539 break;
540 case 'f':
541 tab_list = "1,7,11,15,19,23";
542 /* FORTRAN */
543 break;
544 case 'n': /* ncurses extension */
545 no_op = TRUE;
546 break;
547 case 'p':
548 tab_list = "1,5,9,13,17,21,25,29,33,37,41,45,49,53,57,61";
549 /* PL/I */
550 break;
551 case 's':
552 tab_list = "1,10,55";
553 /* SNOBOL */
554 break;
555 case 'u':
556 tab_list = "1,12,20,44";
557 /* UNIVAC 1100 Assembler */
558 break;
559 case 'T':
560 ++n;
561 if (*++option != '\0') {
562 term_name = option;
563 } else {
564 term_name = argv[n];
565 option--;
566 }
567 option += ((int) strlen(option)) - 1;
568 continue;
569 case 'V':
570 puts(curses_version());
571 ExitProgram(EXIT_SUCCESS);
572 default:
573 if (isdigit(UChar(*option))) {
574 char *copy = strdup(option);
575 *skip_list(copy) = '\0';
576 tab_list = copy;
577 option = skip_list(option) - 1;
578 } else {
579 usage();
580 }
581 break;
582 }
583 }
584 break;
585 case '+':
586 if ((ch = *++option) != '\0') {
587 int digits = 0;
588 int number = 0;
589
590 switch (ch) {
591 case 'm':
592 /*
593 * The "+mXXX" option is unimplemented because only the long-obsolete
594 * att510d implements smgl, which is needed to support
595 * this option.
596 */
597 while ((ch = *++option) != '\0') {
598 if (isdigit(UChar(ch))) {
599 ++digits;
600 number = number * 10 + (ch - '0');
601 } else {
602 usage();
603 }
604 }
605 if (digits == 0)
606 number = 10;
607 margin = number;
608 break;
609 default:
610 /* special case of relative stops separated by spaces? */
611 if (option == argv[n] + 1) {
612 tab_list = add_to_tab_list(&append, argv[n]);
613 }
614 break;
615 }
616 }
617 break;
618 default:
619 if (append != 0) {
620 if (tab_list != (const char *) append) {
621 /* one of the predefined options was used */
622 free(append);
623 append = 0;
624 }
625 }
626 tab_list = add_to_tab_list(&append, option);
627 break;
628 }
629 }
630
631 fd = save_tty_settings(&tty_settings, FALSE);
632
633 setupterm(term_name, fd, (int *) 0);
634
635 max_cols = (columns > 0) ? columns : 80;
636 if (margin > 0)
637 max_cols -= margin;
638
639 if (!VALID_STRING(clear_all_tabs)) {
640 fprintf(stderr,
641 "%s: terminal type '%s' cannot reset tabs\n",
642 _nc_progname, term_name);
643 } else if (!VALID_STRING(set_tab)) {
644 fprintf(stderr,
645 "%s: terminal type '%s' cannot set tabs\n",
646 _nc_progname, term_name);
647 } else if (legal_tab_list(tab_list)) {
648 int *list;
649
650 if (tab_list == NULL)
651 tab_list = add_to_tab_list(&append, "8");
652
653 if (!no_op) {
654 #if defined(TERMIOS) && defined(OCRNL)
655 /* set tty modes to -ocrnl to allow \r */
656 if (isatty(STDOUT_FILENO)) {
657 TTY new_settings = tty_settings;
658 new_settings.c_oflag &= (unsigned) ~OCRNL;
659 update_tty_settings(&tty_settings, &new_settings);
660 change_tty = TRUE;
661 new_line = "\r\n";
662 }
663 #endif
664
665 if (!ansi_clear_tabs())
666 putch('\r');
667 tputs(clear_all_tabs, 1, putch);
668 }
669
670 if (margin >= 0) {
671 putch('\r');
672 if (margin > 0) {
673 /* reset existing margin before setting margin, to reduce
674 * problems moving left of the current margin.
675 */
676 if (do_set_margin(0, no_op))
677 putch('\r');
678 }
679 if (do_set_margin(margin, no_op))
680 margin = -1;
681 }
682
683 list = decode_tabs(tab_list, margin);
684
685 if (list != 0) {
686 if (!no_op)
687 do_tabs(list);
688 if (debug) {
689 fflush(stderr);
690 printf("tabs %s%s", tab_list, new_line);
691 print_ruler(list, new_line);
692 write_tabs(list, new_line);
693 }
694 free(list);
695 } else if (debug) {
696 fflush(stderr);
697 printf("tabs %s%s", tab_list, new_line);
698 }
699 if (!no_op) {
700 if (change_tty) {
701 restore_tty_settings();
702 }
703 }
704 rc = EXIT_SUCCESS;
705 }
706 if (append != 0)
707 free(append);
708 ExitProgram(rc);
709 }
710