xref: /openbsd-src/usr.sbin/installboot/util.c (revision 463390984eb0aed0f709cffa963f0c0c58a8ecf4)
1 /*	$OpenBSD: util.c,v 1.1 2014/01/18 02:47:27 jsing Exp $	*/
2 
3 /*
4  * Copyright (c) 2014 Joel Sing <jsing@openbsd.org>
5  *
6  * Permission to use, copy, modify, and distribute this software for any
7  * purpose with or without fee is hereby granted, provided that the above
8  * copyright notice and this permission notice appear in all copies.
9  *
10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17  */
18 
19 #include <sys/param.h>
20 #include <err.h>
21 #include <stdio.h>
22 #include <stdlib.h>
23 #include <string.h>
24 
25 #include "installboot.h"
26 
27 char *
28 fileprefix(const char *base, const char *path)
29 {
30 	char *r, *s;
31 	int n;
32 
33 	if ((s = malloc(PATH_MAX)) == NULL)
34 		err(1, "malloc");
35 	n = snprintf(s, PATH_MAX, "%s/%s", base, path);
36 	if (n < 1 || n >= PATH_MAX)
37 		err(1, "snprintf");
38 	if ((r = realpath(s, NULL)) == NULL)
39 		err(1, "realpath");
40 	free(s);
41 
42 	return r;
43 }
44