rev.c revision 1.1 
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
41static char sccsid[] = "@(#)rev.c	5.2 (Berkeley) 3/21/92";
42#endif /* not lint */
43
44#include <sys/types.h>
45#include <errno.h>
46#include <stdio.h>
47#include <stdlib.h>
48#include <string.h>
49
50void usage __P((void));
51void warn __P((const char *, ...));
52
53int
54main(argc, argv)
55	int argc;
56	char *argv[];
57{
58	register char *filename, *p, *t;
59	FILE *fp;
60	size_t len;
61	int ch, rval;
62
63	while ((ch = getopt(argc, argv, "")) != EOF)
64		switch(ch) {
65		case '?':
66		default:
67			usage();
68		}
69
70	argc -= optind;
71	argv += optind;
72
73	fp = stdin;
74	filename = "stdin";
75	rval = 0;
76	do {
77		if (*argv) {
78			if ((fp = fopen(*argv, "r")) == NULL) {
79				warn("%s: %s", *argv, strerror(errno));
80				rval = 1;
81				++argv;
82				continue;
83			}
84			filename = *argv++;
85		}
86		while (p = fgetline(fp, &len)) {
87			t = p + len - 1;
88			for (t = p + len - 1; t >= p; --t)
89				putchar(*t);
90			putchar('\n');
91		}
92		if (ferror(fp)) {
93			warn("%s: %s", filename, strerror(errno));
94			rval = 1;
95		}
96		(void)fclose(fp);
97	} while(*argv);
98	exit(rval);
99}
100
101#if __STDC__
102#include <stdarg.h>
103#else
104#include <varargs.h>
105#endif
106
107void
108#if __STDC__
109warn(const char *fmt, ...)
110#else
111warn(fmt, va_alist)
112	char *fmt;
113        va_dcl
114#endif
115{
116	va_list ap;
117#if __STDC__
118	va_start(ap, fmt);
119#else
120	va_start(ap);
121#endif
122	(void)fprintf(stderr, "rev: ");
123	(void)vfprintf(stderr, fmt, ap);
124	va_end(ap);
125	(void)fprintf(stderr, "\n");
126}
127
128void
129usage()
130{
131	(void)fprintf(stderr, "usage: rev [file ...]\n");
132	exit(1);
133}
134