1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2008, Jeffrey Roberson <jeff@freebsd.org> 5 * All rights reserved. 6 * 7 * Copyright (c) 2008 Nokia Corporation 8 * All rights reserved. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice unmodified, this list of conditions, and the following 15 * disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 21 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 22 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 23 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 24 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 25 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 26 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 27 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 28 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 29 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 #ifndef _SYS__BITSET_H_ 33 #define _SYS__BITSET_H_ 34 35 /* 36 * Macros addressing word and bit within it, tuned to make compiler 37 * optimize cases when SETSIZE fits into single machine word. 38 */ 39 #define _BITSET_BITS (sizeof(unsigned long) * 8) 40 41 #define __howmany(x, y) (((x) + ((y) - 1)) / (y)) 42 43 #define __bitset_words(_s) (__howmany(_s, _BITSET_BITS)) 44 45 #define __BITSET_DEFINE(_t, _s) \ 46 struct _t { \ 47 unsigned long __bits[__bitset_words((_s))]; \ 48 } 49 50 /* 51 * Helper to declare a bitset without it's size being a constant. 52 * 53 * Sadly we cannot declare a bitset struct with 'bits[]', because it's 54 * the only member of the struct and the compiler complains. 55 */ 56 #define __BITSET_DEFINE_VAR(_t) __BITSET_DEFINE(_t, 1) 57 58 /* 59 * Define a default type that can be used while manually specifying size 60 * to every call. 61 */ 62 63 #if defined(_KERNEL) || defined(_WANT_FREEBSD_BITSET) 64 __BITSET_DEFINE(bitset, 1); 65 66 #define BITSET_DEFINE(_t, _s) __BITSET_DEFINE(_t, _s) 67 #define BITSET_DEFINE_VAR(_t) __BITSET_DEFINE_VAR(_t) 68 #endif /* defined(_KERNEL) || defined(_WANT_FREEBSD_BITSET) */ 69 70 #endif /* !_SYS__BITSET_H_ */ 71