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 extern int optind;
  40
  41 #define LOWER   1
  42 #define UPPER   2
  43
  44 int
  45 main(ac, av)
  46 int     ac;
  47 char    **av;
  48 {
  49         int     c, x;
  50         int     op;
  51         FILE    *inf;
  52
  53         op = 0;
  54         while ((c = getopt(ac, av, "lnu")) != EOF) {
  55                 switch (c) {
  56                 case 'n':
  57                         setbuf (stdout, (char *)NULL);
  58                         break;
  59                 case 'u':
  60                         op = UPPER;
  61                         break;
  62                 case 'l':
  63                         op = LOWER;
  64                         break;
  65                 default:
  66                         fprintf(stderr, "casemod: usage: casemod [-lnu] [file]\n");
  67                         exit(2);
  68                 }
  69         }
  70         av += optind;
  71         ac -= optind;
  72
  73         if (av[0] && (av[0][0] != '-' || av[0][1])) {
  74                 inf = fopen(av[0], "r");
  75                 if (inf == 0) {
  76                         fprintf(stderr, "casemod: %s: cannot open: %s\n", av[0], strerror(errno));
  77                         exit(1);
  78                 }
  79         } else
  80                 inf = stdin;
  81
  82         while ((c = getc(inf)) != EOF) {
  83                 switch (op) {
  84                 case UPPER:
  85                         x = islower(c) ? toupper(c) : c;
  86                         break;
  87                 case LOWER:
  88                         x = isupper(c) ? tolower(c) : c;
  89                         break;
  90                 default:
  91                         x = c;
  92                         break;
  93                 }
  94                 putchar(x);
  95         }
  96
  97         exit(0);
  98 }