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  * 4. 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
  30 #ifndef lint
  31 static const char copyright[] =
  32 "@(#) Copyright (c) 1980, 1993\n\
  33         The Regents of the University of California.  All rights reserved.\n";
  34 #endif /* not lint */
  35
  36 #ifndef lint
  37 #if 0
  38 static char sccsid[] = "@(#)expand.c    8.1 (Berkeley) 6/9/93";
  39 #endif
  40 #endif /* not lint */
  41 #include <sys/cdefs.h>
  42 __FBSDID("$FreeBSD$");
  43
  44 #include <ctype.h>
  45 #include <err.h>
  46 #include <locale.h>
  47 #include <stdio.h>
  48 #include <stdlib.h>
  49 #include <unistd.h>
  50 #include <wchar.h>
  51 #include <wctype.h>
  52
  53 /*
  54  * expand - expand tabs to equivalent spaces
  55  */
  56 static int      nstops;
  57 static int      tabstops[100];
  58
  59 static void getstops(char *);
  60 static void usage(void);
  61
  62 int
  63 main(int argc, char *argv[])
  64 {
  65         const char *curfile;
  66         wint_t wc;
  67         int c, column;
  68         int n;
  69         int rval;
  70         int width;
  71
  72         setlocale(LC_CTYPE, "");
  73
  74         /* handle obsolete syntax */
  75         while (argc > 1 && argv[1][0] == '-' &&
  76             isdigit((unsigned char)argv[1][1])) {
  77                 getstops(&argv[1][1]);
  78                 argc--; argv++;
  79         }
  80
  81         while ((c = getopt (argc, argv, "t:")) != -1) {
  82                 switch (c) {
  83                 case 't':
  84                         getstops(optarg);
  85                         break;
  86                 case '?':
  87                 default:
  88                         usage();
  89                         /* NOTREACHED */
  90                 }
  91         }
  92         argc -= optind;
  93         argv += optind;
  94
  95         rval = 0;
  96         do {
  97                 if (argc > 0) {
  98                         if (freopen(argv[0], "r", stdin) == NULL) {
  99                                 warn("%s", argv[0]);
 100                                 rval = 1;
 101                                 argc--, argv++;
 102                                 continue;
 103                         }
 104                         curfile = argv[0];
 105                         argc--, argv++;
 106                 } else
 107                         curfile = "stdin";
 108                 column = 0;
 109                 while ((wc = getwchar()) != WEOF) {
 110                         switch (wc) {
 111                         case '\t':
 112                                 if (nstops == 0) {
 113                                         do {
 114                                                 putwchar(' ');
 115                                                 column++;
 116                                         } while (column & 07);
 117                                         continue;
 118                                 }
 119                                 if (nstops == 1) {
 120                                         do {
 121                                                 putwchar(' ');
 122                                                 column++;
 123                                         } while (((column - 1) % tabstops[0]) != (tabstops[0] - 1));
 124                                         continue;
 125                                 }
 126                                 for (n = 0; n < nstops; n++)
 127                                         if (tabstops[n] > column)
 128                                                 break;
 129                                 if (n == nstops) {
 130                                         putwchar(' ');
 131                                         column++;
 132                                         continue;
 133                                 }
 134                                 while (column < tabstops[n]) {
 135                                         putwchar(' ');
 136                                         column++;
 137                                 }
 138                                 continue;
 139
 140                         case '\b':
 141                                 if (column)
 142                                         column--;
 143                                 putwchar('\b');
 144                                 continue;
 145
 146                         default:
 147                                 putwchar(wc);
 148                                 if ((width = wcwidth(wc)) > 0)
 149                                         column += width;
 150                                 continue;
 151
 152                         case '\n':
 153                                 putwchar(wc);
 154                                 column = 0;
 155                                 continue;
 156                         }
 157                 }
 158                 if (ferror(stdin)) {
 159                         warn("%s", curfile);
 160                         rval = 1;
 161                 }
 162         } while (argc > 0);
 163         exit(rval);
 164 }
 165
 166 static void
 167 getstops(char *cp)
 168 {
 169         int i;
 170
 171         nstops = 0;
 172         for (;;) {
 173                 i = 0;
 174                 while (*cp >= '0' && *cp <= '9')
 175                         i = i * 10 + *cp++ - '0';
 176                 if (i <= 0)
 177                         errx(1, "bad tab stop spec");
 178                 if (nstops > 0 && i <= tabstops[nstops-1])
 179                         errx(1, "bad tab stop spec");
 180                 if (nstops == sizeof(tabstops) / sizeof(*tabstops))
 181                         errx(1, "too many tab stops");
 182                 tabstops[nstops++] = i;
 183                 if (*cp == 0)
 184                         break;
 185                 if (*cp != ',' && !isblank((unsigned char)*cp))
 186                         errx(1, "bad tab stop spec");
 187                 cp++;
 188         }
 189 }
 190
 191 static void
 192 usage(void)
 193 {
 194         (void)fprintf (stderr, "usage: expand [-t tablist] [file ...]\n");
 195         exit(1);
 196 }