echo.c revision 1.10 
1/* $NetBSD: echo.c,v 1.10 2003/08/04 22:31:23 jschauma Exp $	*/
2
3/*
4 * Copyright (c) 1989, 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. All advertising materials mentioning features or use of this software
16 *    must display the following acknowledgement:
17 *	This product includes software developed by the University of
18 *	California, Berkeley and its contributors.
19 * 4. Neither the name of the University nor the names of its contributors
20 *    may be used to endorse or promote products derived from this software
21 *    without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 */
35
36#include <sys/cdefs.h>
37#ifndef lint
38__COPYRIGHT(
39"@(#) Copyright (c) 1989, 1993\n\
40	The Regents of the University of California.  All rights reserved.\n");
41#endif /* not lint */
42
43#ifndef lint
44#if 0
45static char sccsid[] = "@(#)echo.c	8.1 (Berkeley) 5/31/93";
46#else
47__RCSID("$NetBSD: echo.c,v 1.10 2003/08/04 22:31:23 jschauma Exp $");
48#endif
49#endif /* not lint */
50
51#include <sys/param.h>
52
53#include <err.h>
54#include <stdio.h>
55#include <stdlib.h>
56#include <string.h>
57#include <unistd.h>
58#include <vis.h>
59
60int stdout_ok;
61
62int main(int, char *[]);
63char *printescaped(const char *);
64
65/* ARGSUSED */
66int
67main(int argc, char *argv[])
68{
69	int nflag;
70
71	stdout_ok = isatty(STDOUT_FILENO);
72	/* This utility may NOT do getopt(3) option parsing. */
73	if (*++argv && !strcmp(*argv, "-n")) {
74		++argv;
75		nflag = 1;
76	}
77	else
78		nflag = 0;
79
80	while (*argv) {
81		char *n;
82		n = printescaped(*argv);
83		(void)printf("%s", n);
84		free(n);
85		if (*++argv)
86			(void)putchar(' ');
87	}
88	if (nflag == 0)
89		(void)putchar('\n');
90	exit(0);
91	/* NOTREACHED */
92}
93
94char *
95printescaped(const char *src)
96{
97	size_t len;
98	char *retval;
99
100	len = strlen(src);
101	if (len != 0 && SIZE_T_MAX/len <= 4) {
102		errx(EXIT_FAILURE, "%s: name too long", src);
103		/* NOTREACHED */
104	}
105
106	retval = (char *)malloc(4*len+1);
107	if (retval != NULL) {
108		if (stdout_ok)
109			(void)strvis(retval, src, VIS_NL | VIS_CSTYLE);
110		else
111			(void)strcpy(retval, src);
112		return retval;
113	} else
114		errx(EXIT_FAILURE, "out of memory!");
115		/* NOTREACHED */
116}
117