1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21
22/*
23 * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
24 * Use is subject to license terms.
25 */
26
27#include "lint.h"
28
29#include <sys/sysmacros.h>
30
31#include <stdlib.h>
32#include <errno.h>
33
34/*
35 * SUSv3 - aligned memory allocation
36 *
37 * From the SUSv3 specification:
38 *    The value of alignment shall be a power
39 *    of two multiple of sizeof (void *).
40 * This is enforced below.
41 *
42 * From the SUSv3 specification:
43 *    If the size of the space requested is 0, the behavior
44 *    is implementation-defined; the value returned in memptr
45 *    shall be either a null pointer or a unique pointer.
46 * We choose always to return a null pointer in this case.
47 * (Not all implementations of memalign() behave this way.)
48 */
49int
50posix_memalign(void **memptr, size_t alignment, size_t size)
51{
52	void *ptr = NULL;
53
54	if ((alignment == 0) || !ISP2(alignment) ||
55	    (alignment & (sizeof (void *) - 1)) != 0) {
56		return (EINVAL);
57	} else if (size == 0) {
58		*memptr = NULL;
59		return (0);
60	} else {
61		if ((ptr = memalign(alignment, size)) == NULL) {
62			return (ENOMEM);
63		} else {
64			*memptr = ptr;
65			return (0);
66		}
67	}
68}
69