echo.c revision 330897 
1/*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1991, 1993
5 *	The Regents of the University of California.  All rights reserved.
6 *
7 * This code is derived from software contributed to Berkeley by
8 * Kenneth Almquist.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 * 4. Neither the name of the University nor the names of its contributors
19 *    may be used to endorse or promote products derived from this software
20 *    without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 *
34 *	@(#)echo.c	8.2 (Berkeley) 5/4/95
35 */
36
37#include <sys/cdefs.h>
38__FBSDID("$FreeBSD: stable/11/bin/sh/bltin/echo.c 330897 2018-03-14 03:19:51Z eadler $");
39
40/*
41 * Echo command.
42 */
43
44#define main echocmd
45
46#include "bltin.h"
47
48/* #define eflag 1 */
49
50int
51main(int argc, char *argv[])
52{
53	char **ap;
54	char *p;
55	char c;
56	int count;
57	int nflag = 0;
58#ifndef eflag
59	int eflag = 0;
60#endif
61
62	ap = argv;
63	if (argc)
64		ap++;
65	if ((p = *ap) != NULL) {
66		if (equal(p, "-n")) {
67			nflag++;
68			ap++;
69		} else if (equal(p, "-e")) {
70#ifndef eflag
71			eflag++;
72#endif
73			ap++;
74		}
75	}
76	while ((p = *ap++) != NULL) {
77		while ((c = *p++) != '\0') {
78			if (c == '\\' && eflag) {
79				switch (*p++) {
80				case 'a':  c = '\a';  break;
81				case 'b':  c = '\b';  break;
82				case 'c':  return 0;		/* exit */
83				case 'e':  c = '\033';  break;
84				case 'f':  c = '\f';  break;
85				case 'n':  c = '\n';  break;
86				case 'r':  c = '\r';  break;
87				case 't':  c = '\t';  break;
88				case 'v':  c = '\v';  break;
89				case '\\':  break;		/* c = '\\' */
90				case '0':
91					c = 0;
92					count = 3;
93					while (--count >= 0 && (unsigned)(*p - '0') < 8)
94						c = (c << 3) + (*p++ - '0');
95					break;
96				default:
97					p--;
98					break;
99				}
100			}
101			putchar(c);
102		}
103		if (*ap)
104			putchar(' ');
105	}
106	if (! nflag)
107		putchar('\n');
108	return 0;
109}
110