summaryrefslogtreecommitdiffstats
path: root/src/kash/bltin/echo.c
blob: ba778b18ba490312279617e201ea50f1dc15f1d6 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
/*	$NetBSD: echo.c,v 1.12 2005/02/06 04:43:43 perry Exp $	*/

/*-
 * Copyright (c) 1991, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Kenneth Almquist.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *	@(#)echo.c	8.1 (Berkeley) 5/31/93
 */

/*
 * Echo command.
 *
 * echo is steeped in tradition - several of them!
 * netbsd has supported 'echo [-n | -e] args' in spite of -e not being
 * documented anywhere.
 * Posix requires that -n be supported, output from strings containing
 * \ is implementation defined
 * The Single Unix Spec requires that \ escapes be treated as if -e
 * were set, but that -n not be treated as an option.
 * (ksh supports 'echo [-eEn] args', but not -- so that it is actually
 * impossible to actually output '-n')
 *
 * It is suggested that 'printf "%b" "string"' be used to get \ sequences
 * expanded.  printf is now a builtin of netbsd's sh and csh.
 */

#include "shinstance.h"
#include "builtins.h"

int
echocmd(shinstance *psh, int argc, char **argv)
{
	char **ap;
	const char *p;
	int nflag = 0;
	int eflag = 0;

	ap = argv;
	if (argc)
		ap++;

	if ((p = *ap) != NULL && *p == '-') {
		if (p[1] == 'n' && !p[2]) {
			nflag = 1;
			ap++;
		} else if (p[1] == 'e' && !p[2]) {
			eflag = 1;
			ap++;
		}
	}

	while ((p = *ap++) != NULL) {
		if (!eflag) {
			out1str(psh, p);
		} else {
			char c;
			int count;

			while ((c = *p++) != '\0') {
				if (c == '\\') {
					switch (*p++) {
					case 'a':  c = '\a';  break;	/* bell */
					case 'b':  c = '\b';  break;
					case 'c':  return 0;		/* exit */
					case 'e':  c =  033;  break;	/* escape */
					case 'f':  c = '\f';  break;
					case 'n':  c = '\n';  break;
					case 'r':  c = '\r';  break;
					case 't':  c = '\t';  break;
					case 'v':  c = '\v';  break;
					case '\\':  break;		/* c = '\\' */
					case '0':
						c = 0;
						count = 3;
						while (--count >= 0 && (unsigned)(*p - '0') < 8)
							c = (c << 3) + (*p++ - '0');
						break;
					default:
						/* Output the '/' and char following */
						p--;
						break;
					}
				}
				out1c(psh, c);
			}
		}
		if (*ap)
			out1c(psh, ' ');
	}
	if (! nflag)
		out1c(psh, '\n');
	return 0;
}