rev.c revision 1.2 
1/*-
2 * Copyright (c) 1987, 1992 The Regents of the University of California.
3 * 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
35char copyright[] =
36"@(#) Copyright (c) 1987, 1992 The Regents of the University of California.\n\
37 All rights reserved.\n";
38#endif /* not lint */
39
40#ifndef lint
41/*static char sccsid[] = "from: @(#)rev.c	5.2 (Berkeley) 3/21/92";*/
42static char rcsid[] = "$Id: rev.c,v 1.2 1993/08/01 18:09:32 mycroft Exp $";
43#endif /* not lint */
44
45#include <sys/types.h>
46#include <errno.h>
47#include <stdio.h>
48#include <stdlib.h>
49#include <string.h>
50
51void usage __P((void));
52void warn __P((const char *, ...));
53
54int
55main(argc, argv)
56	int argc;
57	char *argv[];
58{
59	register char *filename, *p, *t;
60	FILE *fp;
61	size_t len;
62	int ch, rval;
63
64	while ((ch = getopt(argc, argv, "")) != EOF)
65		switch(ch) {
66		case '?':
67		default:
68			usage();
69		}
70
71	argc -= optind;
72	argv += optind;
73
74	fp = stdin;
75	filename = "stdin";
76	rval = 0;
77	do {
78		if (*argv) {
79			if ((fp = fopen(*argv, "r")) == NULL) {
80				warn("%s: %s", *argv, strerror(errno));
81				rval = 1;
82				++argv;
83				continue;
84			}
85			filename = *argv++;
86		}
87		while (p = fgetline(fp, &len)) {
88			t = p + len - 1;
89			for (t = p + len - 1; t >= p; --t)
90				putchar(*t);
91			putchar('\n');
92		}
93		if (ferror(fp)) {
94			warn("%s: %s", filename, strerror(errno));
95			rval = 1;
96		}
97		(void)fclose(fp);
98	} while(*argv);
99	exit(rval);
100}
101
102#if __STDC__
103#include <stdarg.h>
104#else
105#include <varargs.h>
106#endif
107
108void
109#if __STDC__
110warn(const char *fmt, ...)
111#else
112warn(fmt, va_alist)
113	char *fmt;
114        va_dcl
115#endif
116{
117	va_list ap;
118#if __STDC__
119	va_start(ap, fmt);
120#else
121	va_start(ap);
122#endif
123	(void)fprintf(stderr, "rev: ");
124	(void)vfprintf(stderr, fmt, ap);
125	va_end(ap);
126	(void)fprintf(stderr, "\n");
127}
128
129void
130usage()
131{
132	(void)fprintf(stderr, "usage: rev [file ...]\n");
133	exit(1);
134}
135