1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
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. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32 #if 0
33 #ifndef lint
34 static char const copyright[] =
35 "@(#) Copyright (c) 1989, 1993\n\
36 The Regents of the University of California. All rights reserved.\n";
37 #endif /* not lint */
38
39 #ifndef lint
40 static char sccsid[] = "@(#)echo.c 8.1 (Berkeley) 5/31/93";
41 #endif /* not lint */
42 #endif
43 #include <sys/cdefs.h>
44 #include <sys/types.h>
45 #include <sys/uio.h>
46
47 #include <assert.h>
48 #include <capsicum_helpers.h>
49 #include <err.h>
50 #include <errno.h>
51 #include <limits.h>
52 #include <stdlib.h>
53 #include <string.h>
54 #include <unistd.h>
55
56 int
main(int argc,char * argv[])57 main(int argc, char *argv[])
58 {
59 int nflag; /* if not set, output a trailing newline. */
60 int veclen; /* number of writev arguments. */
61 struct iovec *iov, *vp; /* Elements to write, current element. */
62 char space[] = " ";
63 char newline[] = "\n";
64
65 if (caph_limit_stdio() < 0 || caph_enter() < 0)
66 err(1, "capsicum");
67
68 /* This utility may NOT do getopt(3) option parsing. */
69 if (*++argv && !strcmp(*argv, "-n")) {
70 ++argv;
71 --argc;
72 nflag = 1;
73 } else
74 nflag = 0;
75
76 veclen = (argc >= 2) ? (argc - 2) * 2 + 1 : 0;
77
78 if ((vp = iov = malloc((veclen + 1) * sizeof(struct iovec))) == NULL)
79 err(1, "malloc");
80
81 while (argv[0] != NULL) {
82 size_t len;
83
84 len = strlen(argv[0]);
85
86 /*
87 * If the next argument is NULL then this is the last argument,
88 * therefore we need to check for a trailing \c.
89 */
90 if (argv[1] == NULL) {
91 /* is there room for a '\c' and is there one? */
92 if (len >= 2 &&
93 argv[0][len - 2] == '\\' &&
94 argv[0][len - 1] == 'c') {
95 /* chop it and set the no-newline flag. */
96 len -= 2;
97 nflag = 1;
98 }
99 }
100 vp->iov_base = *argv;
101 vp++->iov_len = len;
102 if (*++argv) {
103 vp->iov_base = space;
104 vp++->iov_len = 1;
105 }
106 }
107 if (!nflag) {
108 veclen++;
109 vp->iov_base = newline;
110 vp++->iov_len = 1;
111 }
112 /* assert(veclen == (vp - iov)); */
113 while (veclen) {
114 int nwrite;
115
116 nwrite = (veclen > IOV_MAX) ? IOV_MAX : veclen;
117 if (writev(STDOUT_FILENO, iov, nwrite) == -1)
118 err(1, "write");
119 iov += nwrite;
120 veclen -= nwrite;
121 }
122 return 0;
123 }
124