usr.bin/expand/expand.c

   1 /*
   2  * Copyright (c) 1980, 1993
   3  *      The Regents of the University of California.  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  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by the University of
  16  *      California, Berkeley and its contributors.
  17  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  *
  33  * @(#) Copyright (c) 1980, 1993 The Regents of the University of California.  All rights reserved.
  34  * @(#)expand.c 8.1 (Berkeley) 6/9/93
  35  * $FreeBSD: src/usr.bin/expand/expand.c,v 1.5.2.6 2002/07/09 10:47:59 tjr Exp $
  36  * $DragonFly: src/usr.bin/expand/expand.c,v 1.2 2003/06/17 04:29:26 dillon Exp $
  37  */
  38
  39 #include <ctype.h>
  40 #include <err.h>
  41 #include <locale.h>
  42 #include <stdio.h>
  43 #include <stdlib.h>
  44 #include <unistd.h>
  45
  46 /*
  47  * expand - expand tabs to equivalent spaces
  48  */
  49 int     nstops;
  50 int     tabstops[100];
  51
  52 static void getstops(char *);
  53 static void usage(void);
  54
  55 int
  56 main(argc, argv)
  57         int argc;
  58         char *argv[];
  59 {
  60         register int c, column;
  61         register int n;
  62         int rval;
  63
  64         setlocale(LC_CTYPE, "");
  65
  66         /* handle obsolete syntax */
  67         while (argc > 1 && argv[1][0] == '-' &&
  68             isdigit((unsigned char)argv[1][1])) {
  69                 getstops(&argv[1][1]);
  70                 argc--; argv++;
  71         }
  72
  73         while ((c = getopt (argc, argv, "t:")) != -1) {
  74                 switch (c) {
  75                 case 't':
  76                         getstops(optarg);
  77                         break;
  78                 case '?':
  79                 default:
  80                         usage();
  81                         /* NOTREACHED */
  82                 }
  83         }
  84         argc -= optind;
  85         argv += optind;
  86
  87         rval = 0;
  88         do {
  89                 if (argc > 0) {
  90                         if (freopen(argv[0], "r", stdin) == NULL) {
  91                                 warn("%s", argv[0]);
  92                                 rval = 1;
  93                                 argc--, argv++;
  94                                 continue;
  95                         }
  96                         argc--, argv++;
  97                 }
  98                 column = 0;
  99                 while ((c = getchar()) != EOF) {
 100                         switch (c) {
 101                         case '\t':
 102                                 if (nstops == 0) {
 103                                         do {
 104                                                 putchar(' ');
 105                                                 column++;
 106                                         } while (column & 07);
 107                                         continue;
 108                                 }
 109                                 if (nstops == 1) {
 110                                         do {
 111                                                 putchar(' ');
 112                                                 column++;
 113                                         } while (((column - 1) % tabstops[0]) != (tabstops[0] - 1));
 114                                         continue;
 115                                 }
 116                                 for (n = 0; n < nstops; n++)
 117                                         if (tabstops[n] > column)
 118                                                 break;
 119                                 if (n == nstops) {
 120                                         putchar(' ');
 121                                         column++;
 122                                         continue;
 123                                 }
 124                                 while (column < tabstops[n]) {
 125                                         putchar(' ');
 126                                         column++;
 127                                 }
 128                                 continue;
 129
 130                         case '\b':
 131                                 if (column)
 132                                         column--;
 133                                 putchar('\b');
 134                                 continue;
 135
 136                         default:
 137                                 putchar(c);
 138                                 if (isprint(c))
 139                                         column++;
 140                                 continue;
 141
 142                         case '\n':
 143                                 putchar(c);
 144                                 column = 0;
 145                                 continue;
 146                         }
 147                 }
 148         } while (argc > 0);
 149         exit(rval);
 150 }
 151
 152 static void
 153 getstops(cp)
 154         register char *cp;
 155 {
 156         register int i;
 157
 158         nstops = 0;
 159         for (;;) {
 160                 i = 0;
 161                 while (*cp >= '0' && *cp <= '9')
 162                         i = i * 10 + *cp++ - '0';
 163                 if (i <= 0)
 164                         errx(1, "bad tab stop spec");
 165                 if (nstops > 0 && i <= tabstops[nstops-1])
 166                         errx(1, "bad tab stop spec");
 167                 if (nstops == sizeof(tabstops) / sizeof(*tabstops))
 168                         errx(1, "too many tab stops");
 169                 tabstops[nstops++] = i;
 170                 if (*cp == 0)
 171                         break;
 172                 if (*cp != ',' && !isblank((unsigned char)*cp))
 173                         errx(1, "bad tab stop spec");
 174                 cp++;
 175         }
 176 }
 177
 178 static void
 179 usage()
 180 {
 181         (void)fprintf (stderr, "usage: expand [-t tablist] [file ...]\n");
 182         exit(1);
 183 }