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 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 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 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 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