xref: /freebsd/bin/sh/bltin/echo.c (revision e627b39baccd1ec9129690167cf5e6d860509655)
1 /*-
2  * Copyright (c) 1991, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * This code is derived from software contributed to Berkeley by
6  * Kenneth Almquist.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by the University of
19  *	California, Berkeley and its contributors.
20  * 4. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  *
36  *	@(#)echo.c	8.2 (Berkeley) 5/4/95
37  *	$Id: echo.c,v 1.3 1995/08/23 05:31:06 pst Exp $
38  */
39 
40 /*
41  * Echo command.
42  */
43 
44 #ifdef main
45 #undef main
46 #endif
47 #define main echocmd
48 
49 #include "bltin.h"
50 
51 /* #define eflag 1 */
52 
53 int
54 main(argc, argv)
55 	int argc;
56 	char **argv;
57 {
58 	register char **ap;
59 	register char *p;
60 	register char c;
61 	int count;
62 	int nflag = 0;
63 #ifndef eflag
64 	int eflag = 0;
65 #endif
66 
67 	ap = argv;
68 	if (argc)
69 		ap++;
70 	if ((p = *ap) != NULL) {
71 		if (equal(p, "-n")) {
72 			nflag++;
73 			ap++;
74 		} else if (equal(p, "-e")) {
75 #ifndef eflag
76 			eflag++;
77 #endif
78 			ap++;
79 		}
80 	}
81 	while ((p = *ap++) != NULL) {
82 		while ((c = *p++) != '\0') {
83 			if (c == '\\' && eflag) {
84 				switch (*p++) {
85 				case 'b':  c = '\b';  break;
86 				case 'c':  return 0;		/* exit */
87 				case 'f':  c = '\f';  break;
88 				case 'n':  c = '\n';  break;
89 				case 'r':  c = '\r';  break;
90 				case 't':  c = '\t';  break;
91 				case 'v':  c = '\v';  break;
92 				case '\\':  break;		/* c = '\\' */
93 				case '0':
94 					c = 0;
95 					count = 3;
96 					while (--count >= 0 && (unsigned)(*p - '0') < 8)
97 						c = (c << 3) + (*p++ - '0');
98 					break;
99 				default:
100 					p--;
101 					break;
102 				}
103 			}
104 			putchar(c);
105 		}
106 		if (*ap)
107 			putchar(' ');
108 	}
109 	if (! nflag)
110 		putchar('\n');
111 	return 0;
112 }
113