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. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  * @(#) Copyright (c) 1980, 1993 The Regents of the University of California.  All rights reserved.
  30  * @(#)expand.c 8.1 (Berkeley) 6/9/93
  31  * $FreeBSD: head/usr.bin/expand/expand.c 227238 2011-11-06 18:49:30Z ed $
  32  */
  33
  34 #include <ctype.h>
  35 #include <err.h>
  36 #include <locale.h>
  37 #include <stdio.h>
  38 #include <stdlib.h>
  39 #include <unistd.h>
  40 #include <wchar.h>
  41 #include <wctype.h>
  42
  43 /*
  44  * expand - expand tabs to equivalent spaces
  45  */
  46 static int      nstops;
  47 static int      tabstops[100];
  48
  49 static void getstops(char *);
  50 static void usage(void);
  51
  52 int
  53 main(int argc, char *argv[])
  54 {
  55         const char *curfile;
  56         wint_t wc;
  57         int c, column;
  58         int n;
  59         int rval;
  60         int width;
  61
  62         setlocale(LC_CTYPE, "");
  63
  64         /* handle obsolete syntax */
  65         while (argc > 1 && argv[1][0] == '-' &&
  66             isdigit((unsigned char)argv[1][1])) {
  67                 getstops(&argv[1][1]);
  68                 argc--; argv++;
  69         }
  70
  71         while ((c = getopt (argc, argv, "t:")) != -1) {
  72                 switch (c) {
  73                 case 't':
  74                         getstops(optarg);
  75                         break;
  76                 case '?':
  77                 default:
  78                         usage();
  79                         /* NOTREACHED */
  80                 }
  81         }
  82         argc -= optind;
  83         argv += optind;
  84
  85         rval = 0;
  86         do {
  87                 if (argc > 0) {
  88                         if (freopen(argv[0], "r", stdin) == NULL) {
  89                                 warn("%s", argv[0]);
  90                                 rval = 1;
  91                                 argc--, argv++;
  92                                 continue;
  93                         }
  94                         curfile = argv[0];
  95                         argc--, argv++;
  96                 } else
  97                         curfile = "stdin";
  98                 column = 0;
  99                 while ((wc = getwchar()) != WEOF) {
 100                         switch (wc) {
 101                         case '\t':
 102                                 if (nstops == 0) {
 103                                         do {
 104                                                 putwchar(' ');
 105                                                 column++;
 106                                         } while (column & 07);
 107                                         continue;
 108                                 }
 109                                 if (nstops == 1) {
 110                                         do {
 111                                                 putwchar(' ');
 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                                         putwchar(' ');
 121                                         column++;
 122                                         continue;
 123                                 }
 124                                 while (column < tabstops[n]) {
 125                                         putwchar(' ');
 126                                         column++;
 127                                 }
 128                                 continue;
 129
 130                         case '\b':
 131                                 if (column)
 132                                         column--;
 133                                 putwchar('\b');
 134                                 continue;
 135
 136                         default:
 137                                 putwchar(wc);
 138                                 if ((width = wcwidth(wc)) > 0)
 139                                         column += width;
 140                                 continue;
 141
 142                         case '\n':
 143                                 putwchar(wc);
 144                                 column = 0;
 145                                 continue;
 146                         }
 147                 }
 148                 if (ferror(stdin)) {
 149                         warn("%s", curfile);
 150                         rval = 1;
 151                 }
 152         } while (argc > 0);
 153         exit(rval);
 154 }
 155
 156 static void
 157 getstops(char *cp)
 158 {
 159         int i;
 160
 161         nstops = 0;
 162         for (;;) {
 163                 i = 0;
 164                 while (*cp >= '0' && *cp <= '9')
 165                         i = i * 10 + *cp++ - '0';
 166                 if (i <= 0)
 167                         errx(1, "bad tab stop spec");
 168                 if (nstops > 0 && i <= tabstops[nstops-1])
 169                         errx(1, "bad tab stop spec");
 170                 if (nstops == sizeof(tabstops) / sizeof(*tabstops))
 171                         errx(1, "too many tab stops");
 172                 tabstops[nstops++] = i;
 173                 if (*cp == 0)
 174                         break;
 175                 if (*cp != ',' && !isblank((unsigned char)*cp))
 176                         errx(1, "bad tab stop spec");
 177                 cp++;
 178         }
 179 }
 180
 181 static void
 182 usage(void)
 183 {
 184         fprintf(stderr, "usage: expand [-t tablist] [file ...]\n");
 185         exit(1);
 186 }