text_cmds/colrm/colrm.c

   1 /*-
   2  * Copyright (c) 1991, 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
  34 #ifndef lint
  35 static const char copyright[] =
  36 "@(#) Copyright (c) 1991, 1993\n\
  37         The Regents of the University of California.  All rights reserved.\n";
  38 #endif
  39
  40 #if 0
  41 #ifndef lint
  42 static char sccsid[] = "@(#)colrm.c     8.2 (Berkeley) 5/4/95";
  43 #endif
  44 #endif
  45
  46 #include <sys/cdefs.h>
  47 __FBSDID("$FreeBSD: src/usr.bin/colrm/colrm.c,v 1.12 2004/07/29 09:09:22 tjr Exp $");
  48
  49 #include <sys/types.h>
  50 #include <err.h>
  51 #include <errno.h>
  52 #include <limits.h>
  53 #include <locale.h>
  54 #include <stdio.h>
  55 #include <stdlib.h>
  56 #include <string.h>
  57 #include <unistd.h>
  58 #include <wchar.h>
  59
  60 #define TAB     8
  61
  62 void check(FILE *);
  63 static void usage(void);
  64
  65 int
  66 main(int argc, char *argv[])
  67 {
  68         u_long column, start, stop;
  69         int ch, width;
  70         char *p;
  71
  72         setlocale(LC_ALL, "");
  73
  74         while ((ch = getopt(argc, argv, "")) != -1)
  75                 switch(ch) {
  76                 case '?':
  77                 default:
  78                         usage();
  79                 }
  80         argc -= optind;
  81         argv += optind;
  82
  83         start = stop = 0;
  84         switch(argc) {
  85         case 2:
  86                 if(argv[1]) stop = strtol(argv[1], &p, 10);
  87                 if (stop <= 0 || *p)
  88                         errx(1, "illegal column -- %s", argv[1]);
  89                 /* FALLTHROUGH */
  90         case 1:
  91                 if(argv[0]) start = strtol(argv[0], &p, 10);
  92                 if (start <= 0 || *p)
  93                         errx(1, "illegal column -- %s", argv[0]);
  94                 break;
  95         case 0:
  96                 break;
  97         default:
  98                 usage();
  99         }
 100
 101         if (stop && start > stop)
 102                 errx(1, "illegal start and stop columns");
 103
 104         for (column = 0;;) {
 105                 switch (ch = getwchar()) {
 106                 case WEOF:
 107                         check(stdin);
 108                         break;
 109                 case '\b':
 110                         if (column)
 111                                 --column;
 112                         break;
 113                 case '\n':
 114                         column = 0;
 115                         break;
 116                 case '\t':
 117                         column = (column + TAB) & ~(TAB - 1);
 118                         break;
 119                 default:
 120                         if ((width = wcwidth(ch)) > 0)
 121                                 column += width;
 122                         break;
 123                 }
 124
 125                 if ((!start || column < start || (stop && column > stop)) &&
 126                     putwchar(ch) == WEOF)
 127                         check(stdout);
 128         }
 129 }
 130
 131 void
 132 check(FILE *stream)
 133 {
 134         if (feof(stream))
 135                 exit(0);
 136         if (ferror(stream))
 137                 err(1, "%s", stream == stdin ? "stdin" : "stdout");
 138 }
 139
 140 void
 141 usage(void)
 142 {
 143         (void)fprintf(stderr, "usage: colrm [start [stop]]\n");
 144         exit(1);
 145 }
 146