usr.bin/expand/expand.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-3-Clause
   3  *
   4  * Copyright (c) 1980, 1993
   5  *      The Regents of the University of California.  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  * 3. Neither the name of the University nor the names of its contributors
  16  *    may be used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  */
  31
  32 #ifndef lint
  33 static const char copyright[] =
  34 "@(#) Copyright (c) 1980, 1993\n\
  35         The Regents of the University of California.  All rights reserved.\n";
  36 #endif /* not lint */
  37
  38 #ifndef lint
  39 #if 0
  40 static char sccsid[] = "@(#)expand.c    8.1 (Berkeley) 6/9/93";
  41 #endif
  42 #endif /* not lint */
  43 #include <sys/cdefs.h>
  44 __FBSDID("$FreeBSD$");
  45
  46 #include <ctype.h>
  47 #include <err.h>
  48 #include <locale.h>
  49 #include <stdio.h>
  50 #include <stdlib.h>
  51 #include <unistd.h>
  52 #include <wchar.h>
  53 #include <wctype.h>
  54
  55 /*
  56  * expand - expand tabs to equivalent spaces
  57  */
  58 static int      nstops;
  59 static int      tabstops[100];
  60
  61 static void getstops(char *);
  62 static void usage(void) __dead2;
  63
  64 int
  65 main(int argc, char *argv[])
  66 {
  67         const char *curfile;
  68         wint_t wc;
  69         int c, column;
  70         int n;
  71         int rval;
  72         int width;
  73
  74         setlocale(LC_CTYPE, "");
  75
  76         /* handle obsolete syntax */
  77         while (argc > 1 && argv[1][0] == '-' &&
  78             isdigit((unsigned char)argv[1][1])) {
  79                 getstops(&argv[1][1]);
  80                 argc--; argv++;
  81         }
  82
  83         while ((c = getopt (argc, argv, "t:")) != -1) {
  84                 switch (c) {
  85                 case 't':
  86                         getstops(optarg);
  87                         break;
  88                 case '?':
  89                 default:
  90                         usage();
  91                         /* NOTREACHED */
  92                 }
  93         }
  94         argc -= optind;
  95         argv += optind;
  96
  97         rval = 0;
  98         do {
  99                 if (argc > 0) {
 100                         if (freopen(argv[0], "r", stdin) == NULL) {
 101                                 warn("%s", argv[0]);
 102                                 rval = 1;
 103                                 argc--, argv++;
 104                                 continue;
 105                         }
 106                         curfile = argv[0];
 107                         argc--, argv++;
 108                 } else
 109                         curfile = "stdin";
 110                 column = 0;
 111                 while ((wc = getwchar()) != WEOF) {
 112                         switch (wc) {
 113                         case '\t':
 114                                 if (nstops == 0) {
 115                                         do {
 116                                                 putwchar(' ');
 117                                                 column++;
 118                                         } while (column & 07);
 119                                         continue;
 120                                 }
 121                                 if (nstops == 1) {
 122                                         do {
 123                                                 putwchar(' ');
 124                                                 column++;
 125                                         } while (((column - 1) % tabstops[0]) != (tabstops[0] - 1));
 126                                         continue;
 127                                 }
 128                                 for (n = 0; n < nstops; n++)
 129                                         if (tabstops[n] > column)
 130                                                 break;
 131                                 if (n == nstops) {
 132                                         putwchar(' ');
 133                                         column++;
 134                                         continue;
 135                                 }
 136                                 while (column < tabstops[n]) {
 137                                         putwchar(' ');
 138                                         column++;
 139                                 }
 140                                 continue;
 141
 142                         case '\b':
 143                                 if (column)
 144                                         column--;
 145                                 putwchar('\b');
 146                                 continue;
 147
 148                         default:
 149                                 putwchar(wc);
 150                                 if ((width = wcwidth(wc)) > 0)
 151                                         column += width;
 152                                 continue;
 153
 154                         case '\n':
 155                                 putwchar(wc);
 156                                 column = 0;
 157                                 continue;
 158                         }
 159                 }
 160                 if (ferror(stdin)) {
 161                         warn("%s", curfile);
 162                         rval = 1;
 163                 }
 164         } while (argc > 0);
 165         exit(rval);
 166 }
 167
 168 static void
 169 getstops(char *cp)
 170 {
 171         int i;
 172
 173         nstops = 0;
 174         for (;;) {
 175                 i = 0;
 176                 while (*cp >= '0' && *cp <= '9')
 177                         i = i * 10 + *cp++ - '0';
 178                 if (i <= 0)
 179                         errx(1, "bad tab stop spec");
 180                 if (nstops > 0 && i <= tabstops[nstops-1])
 181                         errx(1, "bad tab stop spec");
 182                 if (nstops == sizeof(tabstops) / sizeof(*tabstops))
 183                         errx(1, "too many tab stops");
 184                 tabstops[nstops++] = i;
 185                 if (*cp == 0)
 186                         break;
 187                 if (*cp != ',' && !isblank((unsigned char)*cp))
 188                         errx(1, "bad tab stop spec");
 189                 cp++;
 190         }
 191 }
 192
 193 static void
 194 usage(void)
 195 {
 196         (void)fprintf (stderr, "usage: expand [-t tablist] [file ...]\n");
 197         exit(1);
 198 }