1/****************************************************************************
2 * Copyright 2020 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
42MODULE_ID("$Id: tabs.c,v 1.42 2020/02/02 23:34:34 tom Exp $")
43
44static void usage(void) GCC_NORETURN;
45
46const char *_nc_progname;
47static int max_cols;
48
49static void
50failed(const char *s)
51{
52    perror(s);
53    ExitProgram(EXIT_FAILURE);
54}
55
56static int
57putch(int c)
58{
59    return putchar(c);
60}
61
62static void
63do_tabs(int *tab_list)
64{
65    int last = 1;
66    int stop;
67
68    putchar('\r');
69    while ((stop = *tab_list++) > 0) {
70	if (last < stop) {
71	    while (last++ < stop) {
72		if (last > max_cols)
73		    break;
74		putchar(' ');
75	    }
76	}
77	if (stop <= max_cols) {
78	    tputs(tparm(set_tab, stop), 1, putch);
79	    last = stop;
80	} else {
81	    break;
82	}
83    }
84    putchar('\r');
85}
86
87static int *
88decode_tabs(const char *tab_list)
89{
90    int *result = typeCalloc(int, strlen(tab_list) + (unsigned) max_cols);
91    int n = 0;
92    int value = 0;
93    int prior = 0;
94    int ch;
95
96    if (result == 0)
97	failed("decode_tabs");
98
99    while ((ch = *tab_list++) != '\0') {
100	if (isdigit(UChar(ch))) {
101	    value *= 10;
102	    value += (ch - '0');
103	} else if (ch == ',') {
104	    result[n] = value + prior;
105	    if (n > 0 && result[n] <= result[n - 1]) {
106		fprintf(stderr,
107			"%s: tab-stops are not in increasing order: %d %d\n",
108			_nc_progname, value, result[n - 1]);
109		free(result);
110		result = 0;
111		break;
112	    }
113	    ++n;
114	    value = 0;
115	    prior = 0;
116	} else if (ch == '+') {
117	    if (n)
118		prior = result[n - 1];
119	}
120    }
121
122    if (result != 0) {
123	/*
124	 * If there is only one value, then it is an option such as "-8".
125	 */
126	if ((n == 0) && (value > 0)) {
127	    int step = value;
128	    value = 1;
129	    while (n < max_cols - 1) {
130		result[n++] = value;
131		value += step;
132	    }
133	}
134
135	/*
136	 * Add the last value, if any.
137	 */
138	result[n++] = value + prior;
139	result[n] = 0;
140    }
141
142    return result;
143}
144
145static void
146print_ruler(int *tab_list)
147{
148    int last = 0;
149    int stop;
150    int n;
151
152    /* first print a readable ruler */
153    for (n = 0; n < max_cols; n += 10) {
154	int ch = 1 + (n / 10);
155	char buffer[20];
156	_nc_SPRINTF(buffer, _nc_SLIMIT(sizeof(buffer))
157		    "----+----%c",
158		    ((ch < 10)
159		     ? (ch + '0')
160		     : (ch + 'A' - 10)));
161	printf("%.*s", ((max_cols - n) > 10) ? 10 : (max_cols - n), buffer);
162    }
163    putchar('\n');
164
165    /* now, print '*' for each stop */
166    for (n = 0, last = 0; (tab_list[n] > 0) && (last < max_cols); ++n) {
167	stop = tab_list[n];
168	while (++last < stop) {
169	    if (last <= max_cols) {
170		putchar('-');
171	    } else {
172		break;
173	    }
174	}
175	if (last <= max_cols) {
176	    putchar('*');
177	    last = stop;
178	} else {
179	    break;
180	}
181    }
182    while (++last <= max_cols)
183	putchar('-');
184    putchar('\n');
185}
186
187/*
188 * Write an '*' on each tabstop, to demonstrate whether it lines up with the
189 * ruler.
190 */
191static void
192write_tabs(int *tab_list)
193{
194    int stop;
195
196    while ((stop = *tab_list++) > 0 && stop <= max_cols) {
197	fputs((stop == 1) ? "*" : "\t*", stdout);
198    };
199    /* also show a tab _past_ the stops */
200    if (stop < max_cols)
201	fputs("\t+", stdout);
202    putchar('\n');
203}
204
205/*
206 * Trim leading/trailing blanks, as well as blanks after a comma.
207 * Convert embedded blanks to commas.
208 */
209static char *
210trimmed_tab_list(const char *source)
211{
212    char *result = strdup(source);
213    int ch, j, k, last;
214
215    if (result != 0) {
216	for (j = k = last = 0; result[j] != 0; ++j) {
217	    ch = UChar(result[j]);
218	    if (isspace(ch)) {
219		if (last == '\0') {
220		    continue;
221		} else if (isdigit(last) || last == ',') {
222		    ch = ',';
223		}
224	    } else if (ch == ',') {
225		;
226	    } else {
227		if (last == ',')
228		    result[k++] = (char) last;
229		result[k++] = (char) ch;
230	    }
231	    last = ch;
232	}
233	result[k] = '\0';
234    }
235    return result;
236}
237
238static bool
239comma_is_needed(const char *source)
240{
241    bool result = FALSE;
242
243    if (source != 0) {
244	size_t len = strlen(source);
245	if (len != 0)
246	    result = (source[len - 1] != ',');
247    } else {
248	result = FALSE;
249    }
250    return result;
251}
252
253/*
254 * Add a command-line parameter to the tab-list.  It can be blank- or comma-
255 * separated (or a mixture).  For simplicity, empty tabs are ignored, e.g.,
256 *	tabs 1,,6,11
257 *	tabs 1,6,11
258 * are treated the same.
259 */
260static const char *
261add_to_tab_list(char **append, const char *value)
262{
263    char *result = *append;
264    char *copied = trimmed_tab_list(value);
265
266    if (copied != 0 && *copied != '\0') {
267	const char *comma = ",";
268	size_t need = 1 + strlen(copied);
269
270	if (*copied == ',')
271	    comma = "";
272	else if (!comma_is_needed(*append))
273	    comma = "";
274
275	need += strlen(comma);
276	if (*append != 0)
277	    need += strlen(*append);
278
279	result = malloc(need);
280	if (result == 0)
281	    failed("add_to_tab_list");
282
283	*result = '\0';
284	if (*append != 0) {
285	    _nc_STRCPY(result, *append, need);
286	    free(*append);
287	}
288	_nc_STRCAT(result, comma, need);
289	_nc_STRCAT(result, copied, need);
290
291	*append = result;
292    }
293    free(copied);
294    return result;
295}
296
297/*
298 * Check for illegal characters in the tab-list.
299 */
300static bool
301legal_tab_list(const char *tab_list)
302{
303    bool result = TRUE;
304
305    if (tab_list != 0 && *tab_list != '\0') {
306	if (comma_is_needed(tab_list)) {
307	    int n, ch;
308	    for (n = 0; tab_list[n] != '\0'; ++n) {
309		ch = UChar(tab_list[n]);
310		if (!(isdigit(ch) || ch == ',' || ch == '+')) {
311		    fprintf(stderr,
312			    "%s: unexpected character found '%c'\n",
313			    _nc_progname, ch);
314		    result = FALSE;
315		    break;
316		}
317	    }
318	} else {
319	    fprintf(stderr, "%s: trailing comma found '%s'\n", _nc_progname, tab_list);
320	    result = FALSE;
321	}
322    } else {
323	fprintf(stderr, "%s: no tab-list given\n", _nc_progname);
324	result = FALSE;
325    }
326    return result;
327}
328
329static char *
330skip_list(char *value)
331{
332    while (*value != '\0' &&
333	   (isdigit(UChar(*value)) ||
334	    isspace(UChar(*value)) ||
335	    strchr("+,", UChar(*value)) != 0)) {
336	++value;
337    }
338    return value;
339}
340
341static void
342usage(void)
343{
344#define DATA(s) s "\n"
345    static const char msg[] =
346    {
347	DATA("Usage: tabs [options] [tabstop-list]")
348	DATA("")
349	DATA("Options:")
350	DATA("  -0       reset tabs")
351	DATA("  -8       set tabs to standard interval")
352	DATA("  -a       Assembler, IBM S/370, first format")
353	DATA("  -a2      Assembler, IBM S/370, second format")
354	DATA("  -c       COBOL, normal format")
355	DATA("  -c2      COBOL compact format")
356	DATA("  -c3      COBOL compact format extended")
357	DATA("  -d       debug (show ruler with expected/actual tab positions)")
358	DATA("  -f       FORTRAN")
359	DATA("  -n       no-op (do not modify terminal settings)")
360	DATA("  -p       PL/I")
361	DATA("  -s       SNOBOL")
362	DATA("  -u       UNIVAC 1100 Assembler")
363	DATA("  -T name  use terminal type 'name'")
364	DATA("  -V       print version")
365	DATA("")
366	DATA("A tabstop-list is an ordered list of column numbers, e.g., 1,11,21")
367	DATA("or 1,+10,+10 which is the same.")
368    };
369#undef DATA
370
371    fflush(stdout);
372    fputs(msg, stderr);
373    ExitProgram(EXIT_FAILURE);
374}
375
376int
377main(int argc, char *argv[])
378{
379    int rc = EXIT_FAILURE;
380    bool debug = FALSE;
381    bool no_op = FALSE;
382    int n, ch;
383    NCURSES_CONST char *term_name = 0;
384    char *append = 0;
385    const char *tab_list = 0;
386    TTY tty_settings;
387    int fd;
388
389    _nc_progname = _nc_rootname(argv[0]);
390
391    fd = save_tty_settings(&tty_settings, FALSE);
392
393    if ((term_name = getenv("TERM")) == 0)
394	term_name = "ansi+tabs";
395
396    /* cannot use getopt, since some options are two-character */
397    for (n = 1; n < argc; ++n) {
398	char *option = argv[n];
399	switch (option[0]) {
400	case '-':
401	    while ((ch = *++option) != '\0') {
402		switch (ch) {
403		case 'a':
404		    switch (*++option) {
405		    default:
406		    case '\0':
407			tab_list = "1,10,16,36,72";
408			option--;
409			/* Assembler, IBM S/370, first format */
410			break;
411		    case '2':
412			tab_list = "1,10,16,40,72";
413			/* Assembler, IBM S/370, second format */
414			break;
415		    }
416		    break;
417		case 'c':
418		    switch (*++option) {
419		    default:
420		    case '\0':
421			tab_list = "1,8,12,16,20,55";
422			option--;
423			/* COBOL, normal format */
424			break;
425		    case '2':
426			tab_list = "1,6,10,14,49";
427			/* COBOL compact format */
428			break;
429		    case '3':
430			tab_list = "1,6,10,14,18,22,26,30,34,38,42,46,50,54,58,62,67";
431			/* COBOL compact format extended */
432			break;
433		    }
434		    break;
435		case 'd':	/* ncurses extension */
436		    debug = TRUE;
437		    break;
438		case 'f':
439		    tab_list = "1,7,11,15,19,23";
440		    /* FORTRAN */
441		    break;
442		case 'n':	/* ncurses extension */
443		    no_op = TRUE;
444		    break;
445		case 'p':
446		    tab_list = "1,5,9,13,17,21,25,29,33,37,41,45,49,53,57,61";
447		    /* PL/I */
448		    break;
449		case 's':
450		    tab_list = "1,10,55";
451		    /* SNOBOL */
452		    break;
453		case 'u':
454		    tab_list = "1,12,20,44";
455		    /* UNIVAC 1100 Assembler */
456		    break;
457		case 'T':
458		    ++n;
459		    if (*++option != '\0') {
460			term_name = option;
461		    } else {
462			term_name = argv[n];
463			option--;
464		    }
465		    option += ((int) strlen(option)) - 1;
466		    continue;
467		case 'V':
468		    puts(curses_version());
469		    ExitProgram(EXIT_SUCCESS);
470		default:
471		    if (isdigit(UChar(*option))) {
472			char *copy = strdup(option);
473			*skip_list(copy) = '\0';
474			tab_list = copy;
475			option = skip_list(option) - 1;
476		    } else {
477			usage();
478		    }
479		    break;
480		}
481	    }
482	    break;
483	case '+':
484	    while ((ch = *++option) != '\0') {
485		switch (ch) {
486		case 'm':
487		    /*
488		     * The "+mXXX" option is unimplemented because only the long-obsolete
489		     * att510d implements smgl, which is needed to support
490		     * this option.
491		     */
492		    break;
493		default:
494		    /* special case of relative stops separated by spaces? */
495		    if (option == argv[n] + 1) {
496			tab_list = add_to_tab_list(&append, argv[n]);
497		    }
498		    break;
499		}
500	    }
501	    break;
502	default:
503	    if (append != 0) {
504		if (tab_list != (const char *) append) {
505		    /* one of the predefined options was used */
506		    free(append);
507		    append = 0;
508		}
509	    }
510	    tab_list = add_to_tab_list(&append, option);
511	    break;
512	}
513    }
514
515    setupterm(term_name, fd, (int *) 0);
516
517    max_cols = (columns > 0) ? columns : 80;
518
519    if (!VALID_STRING(clear_all_tabs)) {
520	fprintf(stderr,
521		"%s: terminal type '%s' cannot reset tabs\n",
522		_nc_progname, term_name);
523    } else if (!VALID_STRING(set_tab)) {
524	fprintf(stderr,
525		"%s: terminal type '%s' cannot set tabs\n",
526		_nc_progname, term_name);
527    } else if (legal_tab_list(tab_list)) {
528	int *list = decode_tabs(tab_list);
529
530	if (!no_op)
531	    tputs(clear_all_tabs, 1, putch);
532
533	if (list != 0) {
534	    if (!no_op)
535		do_tabs(list);
536	    if (debug) {
537		fflush(stderr);
538		printf("tabs %s\n", tab_list);
539		print_ruler(list);
540		write_tabs(list);
541	    }
542	    free(list);
543	} else if (debug) {
544	    fflush(stderr);
545	    printf("tabs %s\n", tab_list);
546	}
547	rc = EXIT_SUCCESS;
548    }
549    if (append != 0)
550	free(append);
551    ExitProgram(rc);
552}
553