/* $NetBSD: memalign.c,v 1.1.1.1 2016/01/13 21:42:18 christos Exp $ */ /* Copyright (C) 1991, 1992, 1993, 1994, 1995 Free Software Foundation, Inc. This library is free software; you can redistribute it and/or modify it under the terms of the GNU Library General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public License for more details. You should have received a copy of the GNU Library General Public License along with this library; see the file COPYING.LIB. If not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ #ifndef _MALLOC_INTERNAL #define _MALLOC_INTERNAL #include #endif __ptr_t (*__memalign_hook) __P ((size_t __size, size_t __alignment)); __ptr_t memalign (alignment, size) __malloc_size_t alignment; __malloc_size_t size; { __ptr_t result; unsigned long int adj; if (__memalign_hook) return (*__memalign_hook) (alignment, size); size = ((size + alignment - 1) / alignment) * alignment; result = malloc (size); if (result == NULL) return NULL; adj = (unsigned long int) ((unsigned long int) ((char *) result - (char *) NULL)) % alignment; if (adj != 0) { struct alignlist *l; for (l = _aligned_blocks; l != NULL; l = l->next) if (l->aligned == NULL) /* This slot is free. Use it. */ break; if (l == NULL) { l = (struct alignlist *) malloc (sizeof (struct alignlist)); if (l == NULL) { free (result); return NULL; } l->next = _aligned_blocks; _aligned_blocks = l; } l->exact = result; result = l->aligned = (char *) result + alignment - adj; } return result; }