usr.bin/tabs/tabs.c

   1 /*-
   2  * Copyright (c) 2002 Tim J. Robbins.
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  24  * SUCH DAMAGE.
  25  *
  26  * $FreeBSD: src/usr.bin/tabs/tabs.c,v 1.3 2002/06/08 11:33:22 tjr Exp $
  27  * $DragonFly: src/usr.bin/tabs/tabs.c,v 1.2 2006/01/12 13:43:11 corecode Exp $
  28  */
  29
  30 /*
  31  * tabs -- set terminal tabs
  32  *
  33  * This utility displays a series of characters that clears the terminal
  34  * hardware tab settings, then initialises them to specified values,
  35  * and optionally sets a soft margin.
  36  */
  37
  38 #include <sys/types.h>
  39 #include <sys/tty.h>
  40
  41 #include <ctype.h>
  42 #include <err.h>
  43 #include <errno.h>
  44 #include <locale.h>
  45 #include <stdio.h>
  46 #include <stdlib.h>
  47 #include <string.h>
  48 #include <term.h>
  49 #include <unistd.h>
  50
  51 /* Maximum number of tab stops allowed in table. */
  52 #define NSTOPS          20
  53
  54 #define NELEMS(a) (sizeof(a) / sizeof(a[0]))
  55
  56 /* Predefined formats, taken from IEEE Std 1003.1-2001. */
  57 static const struct {
  58         const char      *name;          /* Format name used on cmd. line */
  59         long            stops[NSTOPS];  /* Column positions */
  60 } formats[] = {
  61         { "a",  { 1, 10, 16, 36, 72 } },
  62         { "a2", { 1, 10, 16, 40, 72 } },
  63         { "c",  { 1, 8, 12, 16, 20, 55 } },
  64         { "c2", { 1, 6, 10, 14, 49 } },
  65         { "c3", { 1, 6, 10, 14, 18, 22, 26, 30, 34, 38, 42, 46, 50, 54, 58,
  66                 62, 67 } },
  67         { "f",  { 1, 7, 11, 15, 19, 23 } },
  68         { "p",  { 1, 5, 9, 13, 17, 21, 25, 29, 33, 37, 41, 45, 49, 53, 57,
  69                 61 } },
  70         { "s",  { 1, 10, 55 } },
  71         { "u",  { 1, 12, 20, 44 } }
  72 };
  73
  74 static void      gettabs(char *, long *, long *);
  75 static int       ttywidth(void);
  76 static void      usage(void);
  77
  78 int
  79 main(int argc __unused, char *argv[])
  80 {
  81         long cols, i, inc, j, margin, nstops, stops[NSTOPS];
  82         const char *cr, *ct, *st, *ML;
  83         char area[1024], *ap, *arg, *end;
  84
  85         setlocale(LC_ALL, "");
  86
  87         inc = 8;
  88         margin = 0;
  89         nstops = -1;
  90         while ((arg = *++argv) != NULL && (*arg == '-' || *arg == '+')) {
  91                 if (*arg == '+') {
  92                         /* +m[n] or +[n] */
  93                         if (*++arg == 'm')
  94                                 arg++;
  95                         if (*arg != '\0') {
  96                                 errno = 0;
  97                                 margin = strtol(arg, &end, 10);
  98                                 if (errno != 0 || *end != '\0' || margin < 0)
  99                                         errx(1, "%s: invalid margin width",
 100                                             arg);
 101                         } else
 102                                 margin = 10;
 103                 } else if (isdigit(arg[1])) {
 104                         /* -n */
 105                         errno = 0;
 106                         inc = strtol(arg + 1, &end, 10);
 107                         if (errno != 0 || *end != '\0' || inc < 0)
 108                                 errx(1, "%s: invalid increment", arg + 1);
 109                 } else if (arg[1] == 'T') {
 110                         /* -Ttype or -T type */
 111                         if (arg[2] != '\0') {
 112                                 if (setenv("TERM", arg + 2, 1) == -1)
 113                                         err(1, "setenv: cannot set TERM=%s", arg + 2);
 114                         }
 115                         else {
 116                                 if ((arg = *++argv) == NULL)
 117                                         usage();
 118                                 if (setenv("TERM", arg, 1) == -1)
 119                                         err(1, "setenv: cannot set TERM=%s", arg);
 120                         }
 121                 } else if (arg[1] == '-') {
 122                         arg = *++argv;
 123                         break;
 124                 } else {
 125                         /* Predefined format */
 126                         for (i = 0; i < (int)NELEMS(formats); i++)
 127                                 if (strcmp(formats[i].name, arg + 1) == 0)
 128                                         break;
 129                         if (i == NELEMS(formats))
 130                                 usage();
 131                         for (j = nstops = 0; j < NSTOPS &&
 132                             formats[i].stops[j] != 0; j++)
 133                                 stops[nstops++] = formats[i].stops[j];
 134                 }
 135         }
 136
 137         if (arg != NULL) {
 138                 if (nstops != -1)
 139                         usage();
 140                 gettabs(arg, stops, &nstops);
 141         }
 142
 143         /* Initialise terminal, get the strings we need */
 144         setupterm(NULL, 1, NULL);
 145         ap = area;
 146         if ((ct = tgetstr("ct", &ap)) == NULL)
 147                 errx(1, "terminal cannot clear tabs");
 148         if ((st = tgetstr("st", &ap)) == NULL)
 149                 errx(1, "terminal cannot set tabs");
 150         if ((cr = tgetstr("cr", &ap)) == NULL)
 151                 cr = "\r";
 152         ML = tgetstr("ML", &ap);
 153         cols = ttywidth();
 154
 155         /* Clear all tabs. */
 156         putp(cr);
 157         putp(ct);
 158
 159         /*
 160          * Set soft margin.
 161          * XXX Does this actually work?
 162          */
 163         if (ML != NULL) {
 164                 printf("%*s", (int)margin, "");
 165                 putp(ML);
 166         } else if (margin != 0)
 167                 warnx("terminal cannot set left margin");
 168
 169         /* Optionally output new tab stops. */
 170         if (nstops >= 0) {
 171                 printf("%*s", (int)stops[0] - 1, "");
 172                 putp(st);
 173                 for (i = 1; i < nstops; i++) {
 174                         printf("%*s", (int)(stops[i] - stops[i - 1]), "");
 175                         putp(st);
 176                 }
 177         } else if (inc > 0) {
 178                 for (i = 0; i < cols / inc; i++) {
 179                         putp(st);
 180                         printf("%*s", (int)inc, "");
 181                 }
 182                 putp(st);
 183         }
 184         putp(cr);
 185
 186         exit(0);
 187 }
 188
 189 static void
 190 usage(void)
 191 {
 192
 193         fprintf(stderr,
 194 "usage: tabs [-n|-a|-a2|-c|-c2|-c3|-f|-p|-s|-u] [+m[n]] [-T type]\n");
 195         fprintf(stderr,
 196 "       tabs [-T type] [+[n]] n1,[n2,...]\n");
 197         exit(1);
 198 }
 199
 200 static void
 201 gettabs(char *arg, long stops[], long *nstops)
 202 {
 203         char *tok, *end;
 204         long last, stop;
 205
 206         for (last = *nstops = 0, tok = strtok(arg, ","); tok != NULL;
 207             tok = strtok(NULL, ",")) {
 208                 if (*nstops >= NSTOPS)
 209                         errx(1, "too many tab stops (limit %d)", NSTOPS);
 210                 errno = 0;
 211                 stop = strtol(tok, &end, 10);
 212                 if (errno != 0 || *end != '\0' || stop <= 0)
 213                         errx(1, "%s: invalid tab stop", tok);
 214                 if (*tok == '+') {
 215                         if (tok == arg)
 216                                 errx(1, "%s: first tab may not be relative",
 217                                     tok);
 218                         stop += last;
 219                 }
 220                 if (last > stop)
 221                         errx(1, "cannot go backwards");
 222                 last = stops[(*nstops)++] = stop;
 223         }
 224 }
 225
 226 static int
 227 ttywidth(void)
 228 {
 229         struct winsize ws;
 230         int width;
 231
 232         if (ioctl(STDOUT_FILENO, TIOCGWINSZ, &ws) != -1)
 233                 width = ws.ws_col;
 234         else if ((width = tgetnum("co")) == 0) {
 235                 width = 80;
 236                 warnx("cannot find terminal width; defaulted to %d", width);
 237         }
 238
 239         return (width);
 240 }