support/xcase.c

   1 /* xcase - change uppercase characters to lowercase or vice versa. */
   2
   3 /* Copyright (C) 2008,2009 Free Software Foundation, Inc.
   4
   5    This file is part of GNU Bash.
   6
   7    Bash is free software: you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation, either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    Bash is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with Bash.  If not, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21 #ifdef HAVE_CONFIG_H
  22 #include "config.h"
  23 #endif
  24
  25 #include <stdio.h>
  26 #include <ctype.h>
  27
  28 #if HAVE_UNISTD_H
  29 #include <unistd.h>
  30 #endif
  31
  32 #include "bashansi.h"
  33 #include <errno.h>
  34
  35 #ifndef errno
  36 extern int errno;
  37 #endif
  38
  39 #define LOWER   1
  40 #define UPPER   2
  41
  42 int
  43 main(ac, av)
  44 int     ac;
  45 char    **av;
  46 {
  47         int     c, x;
  48         int     op;
  49         FILE    *inf;
  50
  51         op = 0;
  52         while ((c = getopt(ac, av, "lnu")) != EOF) {
  53                 switch (c) {
  54                 case 'n':
  55                         setbuf (stdout, (char *)NULL);
  56                         break;
  57                 case 'u':
  58                         op = UPPER;
  59                         break;
  60                 case 'l':
  61                         op = LOWER;
  62                         break;
  63                 default:
  64                         fprintf(stderr, "casemod: usage: casemod [-lnu] [file]\n");
  65                         exit(2);
  66                 }
  67         }
  68         av += optind;
  69         ac -= optind;
  70
  71         if (av[0] && (av[0][0] != '-' || av[0][1])) {
  72                 inf = fopen(av[0], "r");
  73                 if (inf == 0) {
  74                         fprintf(stderr, "casemod: %s: cannot open: %s\n", av[0], strerror(errno));
  75                         exit(1);
  76                 }
  77         } else
  78                 inf = stdin;
  79
  80         while ((c = getc(inf)) != EOF) {
  81                 switch (op) {
  82                 case UPPER:
  83                         x = islower(c) ? toupper(c) : c;
  84                         break;
  85                 case LOWER:
  86                         x = isupper(c) ? tolower(c) : c;
  87                         break;
  88                 default:
  89                         x = c;
  90                         break;
  91                 }
  92                 putchar(x);
  93         }
  94
  95         exit(0);
  96 }