1/*-
2 * Copyright (c) 2016 Kai Wang
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27#include <sys/param.h>
28#include <assert.h>
29#include <errno.h>
30#include <string.h>
31#include <unistd.h>
32
33#include "_libpe.h"
34
35ELFTC_VCSID("$Id: libpe_utils.c 3312 2016-01-10 09:23:51Z kaiwang27 $");
36
37off_t
38libpe_align(PE *pe, off_t off, size_t align)
39{
40	off_t n;
41
42	assert(align > 0 && (align & (align - 1)) == 0);
43
44	n = roundup(off, align);
45	if (n > off) {
46		if (libpe_pad(pe, n - off) < 0)
47			return (-1);
48	}
49
50	return (n);
51}
52
53int
54libpe_pad(PE *pe, size_t pad)
55{
56	char tmp[128];
57	size_t s;
58
59	memset(tmp, 0, sizeof(tmp));
60	for (; pad > 0; pad -= s) {
61		s = pad > sizeof(tmp) ? sizeof(tmp) : pad;
62		if (write(pe->pe_fd, tmp, s) != (ssize_t) s) {
63			errno = EIO;
64			return (-1);
65		}
66	}
67
68	return (0);
69}
70