/* * Copyright (c) 2013 Apple Inc. All rights reserved. * * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ * * This file contains Original Code and/or Modifications of Original Code * as defined in and that are subject to the Apple Public Source License * Version 2.0 (the 'License'). You may not use this file except in * compliance with the License. The rights granted to you under the License * may not be used to create, or enable the creation or redistribution of, * unlawful or unlicensed copies of an Apple operating system, or to * circumvent, violate, or enable the circumvention or violation of, any * terms of an Apple operating system software license agreement. * * Please obtain a copy of the License at * http://www.opensource.apple.com/apsl/ and read it before using this file. * * The Original Code and all software distributed under the License are * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. * Please see the License for the specific language governing rights and * limitations under the License. * * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ */ /*- * Copyright (c) 1989, 1993 * The Regents of the University of California. All rights reserved. * * This code is derived from software contributed to Berkeley by * Paul Vixie. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #ifndef _SYS_BITSTRING_H_ #define _SYS_BITSTRING_H_ #ifdef XNU_KERNEL_PRIVATE #include <sys/mcache.h> typedef uint8_t bitstr_t; /* internal macros */ /* byte of the bitstring bit is in */ #define _bit_byte(bit) \ ((bit) >> 3) /* mask for the bit within its byte */ #define _bit_mask(bit) \ (1 << ((bit) & 0x7)) /* external macros */ /* bytes in a bitstring of nbits bits */ #define bitstr_size(nbits) \ (((nbits) + 7) >> 3) /* allocate a bitstring on the stack */ #define bit_decl(name, nbits) \ ((name)[bitstr_size(nbits)]) /* is bit N of bitstring name set? */ #define bit_test(name, bit) \ ((name)[_bit_byte(bit)] & _bit_mask(bit)) /* set bit N of bitstring name */ #define bit_set(name, bit) \ ((name)[_bit_byte(bit)] |= _bit_mask(bit)) /* set bit N of bitstring name (atomic) */ #define bit_set_atomic(name, bit) \ atomic_bitset_8(&((name)[_bit_byte(bit)]), _bit_mask(bit)) /* clear bit N of bitstring name */ #define bit_clear(name, bit) \ ((name)[_bit_byte(bit)] &= ~_bit_mask(bit)) /* clear bit N of bitstring name (atomic) */ #define bit_clear_atomic(name, bit) \ atomic_bitclear_8(&((name)[_bit_byte(bit)]), _bit_mask(bit)) /* clear bits start ... stop in bitstring */ #define bit_nclear(name, start, stop) do { \ bitstr_t *_name = (name); \ int _start = (start), _stop = (stop); \ int _startbyte = _bit_byte(_start); \ int _stopbyte = _bit_byte(_stop); \ if (_startbyte == _stopbyte) { \ _name[_startbyte] &= ((0xff >> (8 - (_start & 0x7))) | \ (0xff << ((_stop & 0x7) + 1))); \ } else { \ _name[_startbyte] &= 0xff >> (8 - (_start & 0x7)); \ while (++_startbyte < _stopbyte) \ _name[_startbyte] = 0; \ _name[_stopbyte] &= 0xff << ((_stop & 0x7) + 1); \ } \ } while (0) /* set bits start ... stop in bitstring */ #define bit_nset(name, start, stop) do { \ bitstr_t *_name = (name); \ int _start = (start), _stop = (stop); \ int _startbyte = _bit_byte(_start); \ int _stopbyte = _bit_byte(_stop); \ if (_startbyte == _stopbyte) { \ _name[_startbyte] |= ((0xff << (_start & 0x7)) & \ (0xff >> (7 - (_stop & 0x7)))); \ } else { \ _name[_startbyte] |= 0xff << ((_start) & 0x7); \ while (++_startbyte < _stopbyte) \ _name[_startbyte] = 0xff; \ _name[_stopbyte] |= 0xff >> (7 - (_stop & 0x7)); \ } \ } while (0) /* find first bit clear in name */ #define bit_ffc(name, nbits, value) do { \ bitstr_t *_name = (name); \ int _byte, _nbits = (nbits); \ int _stopbyte = _bit_byte(_nbits - 1), _value = -1; \ if (_nbits > 0) \ for (_byte = 0; _byte <= _stopbyte; ++_byte) \ if (_name[_byte] != 0xff) { \ bitstr_t _lb; \ _value = _byte << 3; \ for (_lb = _name[_byte]; (_lb & 0x1); \ ++_value, _lb >>= 1); \ break; \ } \ if (_value >= nbits) \ _value = -1; \ *(value) = _value; \ } while (0) /* find first bit set in name */ #define bit_ffs(name, nbits, value) do { \ bitstr_t *_name = (name); \ int _byte, _nbits = (nbits); \ int _stopbyte = _bit_byte(_nbits - 1), _value = -1; \ if (_nbits > 0) \ for (_byte = 0; _byte <= _stopbyte; ++_byte) \ if (_name[_byte]) { \ bitstr_t _lb; \ _value = _byte << 3; \ for (_lb = _name[_byte]; !(_lb & 0x1); \ ++_value, _lb >>= 1); \ break; \ } \ if (_value >= nbits) \ _value = -1; \ *(value) = _value; \ } while (0) #endif /* XNU_KERNEL_PRIVATE */ #endif /* !_SYS_BITSTRING_H_ */