usr.bin/rev/rev.c

   1 /*-
   2  * Copyright (c) 1987, 1992, 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) 1987, 1992, 1993 The Regents of the University of California.  All rights reserved.
  30  * @(#)rev.c    8.3 (Berkeley) 5/4/95
  31  */
  32
  33 #include <sys/types.h>
  34
  35 #include <err.h>
  36 #include <locale.h>
  37 #include <stdio.h>
  38 #include <stdlib.h>
  39 #include <unistd.h>
  40 #include <wchar.h>
  41
  42 static void     usage(void);
  43 static int      dorev(FILE *, const char *);
  44
  45 int
  46 main(int argc, char **argv)
  47 {
  48         FILE *fp;
  49         int ch, i, rval;
  50
  51         rval = 0;
  52
  53         setlocale(LC_ALL, "");
  54
  55         while ((ch = getopt(argc, argv, "")) != -1)
  56                 switch(ch) {
  57                 case '?':
  58                 default:
  59                         usage();
  60                 }
  61
  62         argc -= optind;
  63         argv += optind;
  64
  65         if (argc == 0)
  66                 rval += dorev(stdin, "stdin");
  67
  68         for (i = 0; i < argc; ++i) {
  69                 if ((fp = fopen(argv[i], "r")) != NULL) {
  70                         rval += dorev(fp, argv[i]);
  71                         fclose(fp);
  72                 } else {
  73                         warn("failed to open %s", argv[i]);
  74                         rval++ ;
  75                 }
  76         }
  77
  78         exit(rval != 0 ? 1 : 0);
  79 }
  80
  81 static void
  82 usage(void)
  83 {
  84         fprintf(stderr, "usage: rev [file ...]\n");
  85         exit(1);
  86 }
  87
  88 static int
  89 dorev(FILE *fp, const char *filepath)
  90 {
  91         const wchar_t *p, *t;
  92         size_t len;
  93
  94         while ((p = fgetwln(fp, &len)) != NULL) {
  95                         if (p[len - 1] == '\n')
  96                                 --len;
  97                         for (t = p + len - 1; t >= p; --t)
  98                                 putwchar(*t);
  99                         putwchar('\n');
 100         }
 101
 102         if (ferror(fp)) {
 103                 warn("%s", filepath);
 104                 /* Reset error indicator */
 105                 clearerr(fp);
 106                 return(1);
 107         }
 108
 109         return(0);
 110 }