xref: /freebsd/usr.bin/rev/rev.c (revision 624e87b673064ae228b79cde11b82f1ad7502bc3)
1  /*-
2   * SPDX-License-Identifier: BSD-3-Clause
3   *
4   * Copyright (c) 1987, 1992, 1993
5   *	The Regents of the University of California.  All rights reserved.
6   *
7   * Redistribution and use in source and binary forms, with or without
8   * modification, are permitted provided that the following conditions
9   * are met:
10   * 1. Redistributions of source code must retain the above copyright
11   *    notice, this list of conditions and the following disclaimer.
12   * 2. Redistributions in binary form must reproduce the above copyright
13   *    notice, this list of conditions and the following disclaimer in the
14   *    documentation and/or other materials provided with the distribution.
15   * 3. Neither the name of the University nor the names of its contributors
16   *    may be used to endorse or promote products derived from this software
17   *    without specific prior written permission.
18   *
19   * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20   * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22   * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23   * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25   * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26   * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27   * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28   * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29   * SUCH DAMAGE.
30   */
31  
32  #ifndef lint
33  static const char copyright[] =
34  "@(#) Copyright (c) 1987, 1992, 1993\n\
35  	The Regents of the University of California.  All rights reserved.\n";
36  #endif /* not lint */
37  
38  #if 0
39  #ifndef lint
40  static char sccsid[] = "@(#)rev.c	8.3 (Berkeley) 5/4/95";
41  #endif /* not lint */
42  #endif
43  
44  #include <sys/cdefs.h>
45  __FBSDID("$FreeBSD$");
46  
47  #include <sys/types.h>
48  
49  #include <err.h>
50  #include <errno.h>
51  #include <locale.h>
52  #include <stdio.h>
53  #include <stdlib.h>
54  #include <string.h>
55  #include <unistd.h>
56  #include <wchar.h>
57  
58  static void usage(void);
59  
60  int
61  main(int argc, char *argv[])
62  {
63  	const char *filename;
64  	wchar_t *p, *t;
65  	FILE *fp;
66  	size_t len;
67  	int ch, rval;
68  
69  	setlocale(LC_ALL, "");
70  
71  	while ((ch = getopt(argc, argv, "")) != -1)
72  		switch(ch) {
73  		case '?':
74  		default:
75  			usage();
76  		}
77  
78  	argc -= optind;
79  	argv += optind;
80  
81  	fp = stdin;
82  	filename = "stdin";
83  	rval = 0;
84  	do {
85  		if (*argv) {
86  			if ((fp = fopen(*argv, "r")) == NULL) {
87  				warn("%s", *argv);
88  				rval = 1;
89  				++argv;
90  				continue;
91  			}
92  			filename = *argv++;
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  		if (ferror(fp)) {
102  			warn("%s", filename);
103  			clearerr(fp);
104  			rval = 1;
105  		}
106  		(void)fclose(fp);
107  	} while(*argv);
108  	exit(rval);
109  }
110  
111  void
112  usage(void)
113  {
114  	(void)fprintf(stderr, "usage: rev [file ...]\n");
115  	exit(1);
116  }
117