1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2002 Tim J. Robbins.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29 /*
30 * tabs -- set terminal tabs
31 *
32 * This utility displays a series of characters that clears the terminal
33 * hardware tab settings, then initialises them to specified values,
34 * and optionally sets a soft margin.
35 */
36
37 #include <sys/types.h>
38 #include <sys/tty.h>
39
40 #include <ctype.h>
41 #include <err.h>
42 #include <errno.h>
43 #include <locale.h>
44 #include <stdio.h>
45 #include <stdlib.h>
46 #include <string.h>
47 #include <term.h>
48 #include <unistd.h>
49
50 /* Maximum number of tab stops allowed in table. */
51 #define NSTOPS 20
52
53 #define NELEMS(a) (sizeof(a) / sizeof(a[0]))
54
55 /* Predefined formats, taken from IEEE Std 1003.1-2001. */
56 static const struct {
57 const char *name; /* Format name used on cmd. line */
58 long stops[NSTOPS]; /* Column positions */
59 } formats[] = {
60 { "a", { 1, 10, 16, 36, 72 } },
61 { "a2", { 1, 10, 16, 40, 72 } },
62 { "c", { 1, 8, 12, 16, 20, 55 } },
63 { "c2", { 1, 6, 10, 14, 49 } },
64 { "c3", { 1, 6, 10, 14, 18, 22, 26, 30, 34, 38, 42, 46, 50, 54, 58,
65 62, 67 } },
66 { "f", { 1, 7, 11, 15, 19, 23 } },
67 { "p", { 1, 5, 9, 13, 17, 21, 25, 29, 33, 37, 41, 45, 49, 53, 57,
68 61 } },
69 { "s", { 1, 10, 55 } },
70 { "u", { 1, 12, 20, 44 } }
71 };
72
73 static void gettabs(char *, long *, long *);
74 static int ttywidth(void);
75 static void usage(void);
76
77 int
main(int argc __unused,char * argv[])78 main(int argc __unused, char *argv[])
79 {
80 long cols, i, inc, j, margin, nstops, stops[NSTOPS];
81 const char *cr, *ct, *st, *ML;
82 char area[1024], *ap, *arg, *end;
83
84 setlocale(LC_ALL, "");
85
86 inc = 8;
87 margin = 0;
88 nstops = -1;
89 while ((arg = *++argv) != NULL && (*arg == '-' || *arg == '+')) {
90 if (*arg == '+') {
91 /* +m[n] or +[n] */
92 if (*++arg == 'm')
93 arg++;
94 if (*arg != '\0') {
95 errno = 0;
96 margin = strtol(arg, &end, 10);
97 if (errno != 0 || *end != '\0' || margin < 0)
98 errx(1, "%s: invalid margin width",
99 arg);
100 } else
101 margin = 10;
102 } else if (isdigit(arg[1])) {
103 /* -n */
104 errno = 0;
105 inc = strtol(arg + 1, &end, 10);
106 if (errno != 0 || *end != '\0' || inc < 0)
107 errx(1, "%s: invalid increment", arg + 1);
108 } else if (arg[1] == 'T') {
109 /* -Ttype or -T type */
110 if (arg[2] != '\0')
111 setenv("TERM", arg + 2, 1);
112 else {
113 if ((arg = *++argv) == NULL)
114 usage();
115 setenv("TERM", arg, 1);
116 }
117 } else if (arg[1] == '-') {
118 arg = *++argv;
119 break;
120 } else {
121 /* Predefined format */
122 for (i = 0; i < (int)NELEMS(formats); i++)
123 if (strcmp(formats[i].name, arg + 1) == 0)
124 break;
125 if (i == NELEMS(formats))
126 usage();
127 for (j = nstops = 0; j < NSTOPS &&
128 formats[i].stops[j] != 0; j++)
129 stops[nstops++] = formats[i].stops[j];
130 }
131 }
132
133 if (arg != NULL) {
134 if (nstops != -1)
135 usage();
136 gettabs(arg, stops, &nstops);
137 }
138
139 /* Initialise terminal, get the strings we need */
140 setupterm(NULL, 1, NULL);
141 ap = area;
142 if ((ct = tgetstr("ct", &ap)) == NULL)
143 errx(1, "terminal cannot clear tabs");
144 if ((st = tgetstr("st", &ap)) == NULL)
145 errx(1, "terminal cannot set tabs");
146 if ((cr = tgetstr("cr", &ap)) == NULL)
147 cr = "\r";
148 ML = tgetstr("ML", &ap);
149 cols = ttywidth();
150
151 /* Clear all tabs. */
152 putp(cr);
153 putp(ct);
154
155 /*
156 * Set soft margin.
157 * XXX Does this actually work?
158 */
159 if (ML != NULL) {
160 printf("%*s", (int)margin, "");
161 putp(ML);
162 } else if (margin != 0)
163 warnx("terminal cannot set left margin");
164
165 /* Optionally output new tab stops. */
166 if (nstops >= 0) {
167 printf("%*s", (int)stops[0] - 1, "");
168 putp(st);
169 for (i = 1; i < nstops; i++) {
170 printf("%*s", (int)(stops[i] - stops[i - 1]), "");
171 putp(st);
172 }
173 } else if (inc > 0) {
174 for (i = 0; i < cols / inc; i++) {
175 putp(st);
176 printf("%*s", (int)inc, "");
177 }
178 putp(st);
179 }
180 putp(cr);
181
182 exit(0);
183 }
184
185 static void
usage(void)186 usage(void)
187 {
188
189 fprintf(stderr,
190 "usage: tabs [-n|-a|-a2|-c|-c2|-c3|-f|-p|-s|-u] [+m[n]] [-T type]\n");
191 fprintf(stderr,
192 " tabs [-T type] [+[n]] n1,[n2,...]\n");
193 exit(1);
194 }
195
196 static void
gettabs(char * arg,long stops[],long * nstops)197 gettabs(char *arg, long stops[], long *nstops)
198 {
199 char *tok, *end;
200 long last, stop;
201
202 for (last = *nstops = 0, tok = strtok(arg, ","); tok != NULL;
203 tok = strtok(NULL, ",")) {
204 if (*nstops >= NSTOPS)
205 errx(1, "too many tab stops (limit %d)", NSTOPS);
206 errno = 0;
207 stop = strtol(tok, &end, 10);
208 if (errno != 0 || *end != '\0' || stop <= 0)
209 errx(1, "%s: invalid tab stop", tok);
210 if (*tok == '+') {
211 if (tok == arg)
212 errx(1, "%s: first tab may not be relative",
213 tok);
214 stop += last;
215 }
216 if (last > stop)
217 errx(1, "cannot go backwards");
218 last = stops[(*nstops)++] = stop;
219 }
220 }
221
222 static int
ttywidth(void)223 ttywidth(void)
224 {
225 struct winsize ws;
226 int width;
227
228 if (ioctl(STDOUT_FILENO, TIOCGWINSZ, &ws) != -1)
229 width = ws.ws_col;
230 else if ((width = tgetnum("co")) == 0) {
231 width = 80;
232 warnx("cannot find terminal width; defaulted to %d", width);
233 }
234
235 return (width);
236 }
237