usr.bin/unexpand/unexpand.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  * @(#)unexpand.c       8.1 (Berkeley) 6/6/93
  31  * $FreeBSD: head/usr.bin/unexpand/unexpand.c 227192 2011-11-06 08:18:05Z ed $
  32  */
  33
  34 /*
  35  * unexpand - put tabs into a file replacing blanks
  36  */
  37 #include <ctype.h>
  38 #include <err.h>
  39 #include <limits.h>
  40 #include <locale.h>
  41 #include <stdio.h>
  42 #include <stdlib.h>
  43 #include <string.h>
  44 #include <unistd.h>
  45 #include <wchar.h>
  46 #include <wctype.h>
  47
  48 static int      all;
  49 static int      nstops;
  50 static int      tabstops[100];
  51
  52 static void getstops(const char *);
  53 static void usage(void);
  54 static int tabify(const char *);
  55
  56 int
  57 main(int argc, char *argv[])
  58 {
  59         int ch, failed;
  60         char *filename;
  61
  62         setlocale(LC_CTYPE, "");
  63
  64         nstops = 1;
  65         tabstops[0] = 8;
  66         while ((ch = getopt(argc, argv, "at:")) != -1) {
  67                 switch (ch) {
  68                 case 'a':       /* Un-expand all spaces, not just leading. */
  69                         all = 1;
  70                         break;
  71                 case 't':       /* Specify tab list, implies -a. */
  72                         getstops(optarg);
  73                         all = 1;
  74                         break;
  75                 default:
  76                         usage();
  77                         /*NOTREACHED*/
  78                 }
  79         }
  80         argc -= optind;
  81         argv += optind;
  82
  83         failed = 0;
  84         if (argc == 0)
  85                 failed |= tabify("stdin");
  86         else {
  87                 while ((filename = *argv++) != NULL) {
  88                         if (freopen(filename, "r", stdin) == NULL) {
  89                                 warn("%s", filename);
  90                                 failed = 1;
  91                         } else
  92                                 failed |= tabify(filename);
  93                 }
  94         }
  95         exit(failed != 0);
  96 }
  97
  98 static void
  99 usage(void)
 100 {
 101         fprintf(stderr, "usage: unexpand [-a | -t tablist] [file ...]\n");
 102         exit(1);
 103 }
 104
 105 static int
 106 tabify(const char *curfile)
 107 {
 108         int dcol, doneline, limit, n, ocol, width;
 109         wint_t ch;
 110
 111         limit = nstops == 1 ? INT_MAX : tabstops[nstops - 1] - 1;
 112
 113         doneline = ocol = dcol = 0;
 114         while ((ch = getwchar()) != WEOF) {
 115                 if (ch == ' ' && !doneline) {
 116                         if (++dcol >= limit)
 117                                 doneline = 1;
 118                         continue;
 119                 } else if (ch == '\t') {
 120                         if (nstops == 1) {
 121                                 dcol = (1 + dcol / tabstops[0]) *
 122                                     tabstops[0];
 123                                 continue;
 124                         } else {
 125                                 for (n = 0; n < nstops &&
 126                                     tabstops[n] - 1 < dcol; n++)
 127                                         ;
 128                                 if (n < nstops - 1 && tabstops[n] - 1 < limit) {
 129                                         dcol = tabstops[n];
 130                                         continue;
 131                                 }
 132                                 doneline = 1;
 133                         }
 134                 }
 135
 136                 /* Output maximal number of tabs. */
 137                 if (nstops == 1) {
 138                         while (((ocol + tabstops[0]) / tabstops[0])
 139                             <= (dcol / tabstops[0])) {
 140                                 if (dcol - ocol < 2)
 141                                         break;
 142                                 putwchar('\t');
 143                                 ocol = (1 + ocol / tabstops[0]) *
 144                                     tabstops[0];
 145                         }
 146                 } else {
 147                         for (n = 0; n < nstops && tabstops[n] - 1 < ocol; n++)
 148                                 ;
 149                         while (ocol < dcol && n < nstops && ocol < limit) {
 150                                 putwchar('\t');
 151                                 ocol = tabstops[n++];
 152                         }
 153                 }
 154
 155                 /* Then spaces. */
 156                 while (ocol < dcol && ocol < limit) {
 157                         putwchar(' ');
 158                         ocol++;
 159                 }
 160
 161                 if (ch == '\b') {
 162                         putwchar('\b');
 163                         if (ocol > 0)
 164                                 ocol--, dcol--;
 165                 } else if (ch == '\n') {
 166                         putwchar('\n');
 167                         doneline = ocol = dcol = 0;
 168                         continue;
 169                 } else if (ch != ' ' || dcol > limit) {
 170                         putwchar(ch);
 171                         if ((width = wcwidth(ch)) > 0)
 172                                 ocol += width, dcol += width;
 173                 }
 174
 175                 /*
 176                  * Only processing leading blanks or we've gone past the
 177                  * last tab stop. Emit remainder of this line unchanged.
 178                  */
 179                 if (!all || dcol >= limit) {
 180                         while ((ch = getwchar()) != '\n' && ch != WEOF)
 181                                 putwchar(ch);
 182                         if (ch == '\n')
 183                                 putwchar('\n');
 184                         doneline = ocol = dcol = 0;
 185                 }
 186         }
 187         if (ferror(stdin)) {
 188                 warn("%s", curfile);
 189                 return (1);
 190         }
 191         return (0);
 192 }
 193
 194 static void
 195 getstops(const char *cp)
 196 {
 197         int i;
 198
 199         nstops = 0;
 200         for (;;) {
 201                 i = 0;
 202                 while (*cp >= '0' && *cp <= '9')
 203                         i = i * 10 + *cp++ - '0';
 204                 if (i <= 0)
 205                         errx(1, "bad tab stop spec");
 206                 if (nstops > 0 && i <= tabstops[nstops-1])
 207                         errx(1, "bad tab stop spec");
 208                 if (nstops == sizeof(tabstops) / sizeof(*tabstops))
 209                         errx(1, "too many tab stops");
 210                 tabstops[nstops++] = i;
 211                 if (*cp == 0)
 212                         break;
 213                 if (*cp != ',' && !isblank((unsigned char)*cp))
 214                         errx(1, "bad tab stop spec");
 215                 cp++;
 216         }
 217 }