1/*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2012 Jeremie Le Hen <jlh@FreeBSD.org>
5 * 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 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29#include <err.h>
30#include <stdio.h>
31#include <stdlib.h>
32#include <unistd.h>
33
34#define	LIBSTDBUF	"/usr/lib/libstdbuf.so"
35#define	LIBSTDBUF32	"/usr/lib32/libstdbuf.so"
36
37static int
38appendenv(const char *key, const char *value)
39{
40	char *curval, *newpair;
41	int ret;
42
43	curval = getenv(key);
44	if (curval == NULL)
45		ret = asprintf(&newpair, "%s=%s", key, value);
46	else
47		ret = asprintf(&newpair, "%s=%s:%s", key, curval, value);
48	if (ret > 0)
49		ret = putenv(newpair);
50	if (ret < 0)
51		warn("Failed to set environment variable: %s", key);
52	return (ret);
53}
54
55static void
56usage(void)
57{
58
59	fprintf(stderr,
60	    "usage: stdbuf [-e 0|L|B|<sz>] [-i 0|L|B|<sz>] [-o 0|L|B|<sz>] "
61	    "<cmd> [args ...]\n");
62	exit(1);
63}
64
65int
66main(int argc, char *argv[])
67{
68	char *ibuf, *obuf, *ebuf;
69	int i;
70
71	ibuf = obuf = ebuf = NULL;
72	while ((i = getopt(argc, argv, "e:i:o:")) != -1) {
73		switch (i) {
74		case 'e':
75			ebuf = optarg;
76			break;
77		case 'i':
78			ibuf = optarg;
79			break;
80		case 'o':
81			obuf = optarg;
82			break;
83		default:
84			usage();
85			break;
86		}
87	}
88	argc -= optind;
89	argv += optind;
90	if (argc == 0)
91		exit(0);
92
93	if (ibuf != NULL && setenv("_STDBUF_I", ibuf, 1) == -1)
94		warn("Failed to set environment variable: %s=%s",
95		    "_STDBUF_I", ibuf);
96	if (obuf != NULL && setenv("_STDBUF_O", obuf, 1) == -1)
97		warn("Failed to set environment variable: %s=%s",
98		    "_STDBUF_O", obuf);
99	if (ebuf != NULL && setenv("_STDBUF_E", ebuf, 1) == -1)
100		warn("Failed to set environment variable: %s=%s",
101		    "_STDBUF_E", ebuf);
102
103	appendenv("LD_PRELOAD", LIBSTDBUF);
104	appendenv("LD_32_PRELOAD", LIBSTDBUF32);
105
106	execvp(argv[0], argv);
107	err(2, "%s", argv[0]);
108}
109