69 lines
2.4 KiB
C
69 lines
2.4 KiB
C
/* $NetBSD: aligned_alloc.c,v 1.2 2018/07/27 13:08:47 maya Exp $ */
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/*-
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* Copyright (C) 2015 The NetBSD Foundation, Inc.
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* All rights reserved.
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*
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* This code is derived from software contributed to The NetBSD Foundation
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* by Niclas Rosenvik.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice(s), this list of conditions and the following disclaimer as
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* the first lines of this file unmodified other than the possible
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* addition of one or more copyright notices.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice(s), this list of conditions and the following disclaimer in
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* the documentation and/or other materials provided with the
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* distribution.
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*
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) ``AS IS'' AND ANY
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* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) BE
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* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
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* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
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* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
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* BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
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* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
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* OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
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* EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*/
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#include <errno.h>
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#include <stdlib.h>
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void *
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aligned_alloc(size_t alignment, size_t size)
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{
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void *memptr;
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int err;
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/*
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* Check that alignment is a power of 2.
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*/
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if (alignment == 0 || ((alignment - 1) & alignment) != 0) {
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errno = EINVAL;
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return NULL;
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}
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/*
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* Adjust alignment to satisfy posix_memalign,
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* larger alignments satisfy smaller alignments.
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*/
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while (alignment < sizeof(void *)) {
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alignment <<= 1;
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}
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err = posix_memalign(&memptr, alignment, size);
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if (err) {
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errno = err;
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return NULL;
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}
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return memptr;
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}
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