[apple/xnu.git] / bsd / sys / bitstring.h

/*
 * Copyright (c) 2013-2016 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 _bitstr_byte(bit)                                               \
	((bit) >> 3)

/* mask for the bit within its byte */
#define _bitstr_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 bitstr_test(name, bit)                                          \
	((name)[_bitstr_byte(bit)] & _bitstr_mask(bit))

/* set bit N of bitstring name */
#define bitstr_set(name, bit)                                           \
	((name)[_bitstr_byte(bit)] |= _bitstr_mask(bit))

/* set bit N of bitstring name (atomic) */
#define bitstr_set_atomic(name, bit)                                    \
	(void)os_atomic_or(&((name)[_bitstr_byte(bit)]), _bitstr_mask(bit), relaxed)

/* clear bit N of bitstring name */
#define bitstr_clear(name, bit)                                         \
	((name)[_bitstr_byte(bit)] &= ~_bitstr_mask(bit))

/* clear bit N of bitstring name (atomic) */
#define bitstr_clear_atomic(name, bit)                                  \
	(void)os_atomic_andnot(&((name)[_bitstr_byte(bit)]), _bitstr_mask(bit), relaxed)

/* clear bits start ... stop in bitstring */
#define bitstr_nclear(name, start, stop) do {                           \
	bitstr_t *_name = (name);                                       \
	int _start = (start), _stop = (stop);                           \
	int _startbyte = _bitstr_byte(_start);                          \
	int _stopbyte = _bitstr_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 bitstr_nset(name, start, stop) do {                             \
	bitstr_t *_name = (name);                                       \
	int _start = (start), _stop = (stop);                           \
	int _startbyte = _bitstr_byte(_start);                          \
	int _stopbyte = _bitstr_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 bitstr_ffc(name, nbits, value) do {                             \
	bitstr_t *_name = (name);                                       \
	int _byte, _nbits = (nbits);                                    \
	int _stopbyte = _bitstr_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 bitstr_ffs(name, nbits, value) do {                             \
	bitstr_t *_name = (name);                                       \
	int _byte, _nbits = (nbits);                                    \
	int _stopbyte = _bitstr_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_ */
Commit	Line	Data
39236c6e	1	/*
5ba3f43e	2	* Copyright (c) 2013-2016 Apple Inc. All rights reserved.
39236c6e A	3	*
	4	* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
	5	*
	6	* This file contains Original Code and/or Modifications of Original Code
	7	* as defined in and that are subject to the Apple Public Source License
	8	* Version 2.0 (the 'License'). You may not use this file except in
	9	* compliance with the License. The rights granted to you under the License
	10	* may not be used to create, or enable the creation or redistribution of,
	11	* unlawful or unlicensed copies of an Apple operating system, or to
	12	* circumvent, violate, or enable the circumvention or violation of, any
	13	* terms of an Apple operating system software license agreement.
	14	*
	15	* Please obtain a copy of the License at
	16	* http://www.opensource.apple.com/apsl/ and read it before using this file.
	17	*
	18	* The Original Code and all software distributed under the License are
	19	* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
	20	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
	21	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
	22	* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
	23	* Please see the License for the specific language governing rights and
	24	* limitations under the License.
	25	*
	26	* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
	27	*/
	28
	29	/*-
	30	* Copyright (c) 1989, 1993
	31	* The Regents of the University of California. All rights reserved.
	32	*
	33	* This code is derived from software contributed to Berkeley by
	34	* Paul Vixie.
	35	*
	36	* Redistribution and use in source and binary forms, with or without
	37	* modification, are permitted provided that the following conditions
	38	* are met:
	39	* 1. Redistributions of source code must retain the above copyright
	40	* notice, this list of conditions and the following disclaimer.
	41	* 2. Redistributions in binary form must reproduce the above copyright
	42	* notice, this list of conditions and the following disclaimer in the
	43	* documentation and/or other materials provided with the distribution.
	44	* 4. Neither the name of the University nor the names of its contributors
	45	* may be used to endorse or promote products derived from this software
	46	* without specific prior written permission.
	47	*
	48	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	49	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	50	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	51	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	52	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	53	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	54	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	55	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	56	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	57	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	58	* SUCH DAMAGE.
	59	*/
	60
	61	#ifndef _SYS_BITSTRING_H_
0a7de745	62	#define _SYS_BITSTRING_H_
39236c6e A	63
	64	#ifdef XNU_KERNEL_PRIVATE
	65	#include <sys/mcache.h>
	66
0a7de745	67	typedef uint8_t bitstr_t;
39236c6e A	68
39236c6e A	69	/* internal macros */
0a7de745 A	70	/* byte of the bitstring bit is in */
0a7de745 A	71	#define _bitstr_byte(bit) \
39236c6e A	72	((bit) >> 3)
39236c6e A	73
0a7de745 A	74	/* mask for the bit within its byte */
0a7de745 A	75	#define _bitstr_mask(bit) \
39236c6e A	76	(1 << ((bit) & 0x7))
	77
	78	/* external macros */
0a7de745 A	79	/* bytes in a bitstring of nbits bits */
0a7de745 A	80	#define bitstr_size(nbits) \
39236c6e A	81	(((nbits) + 7) >> 3)
39236c6e A	82
0a7de745 A	83	/* allocate a bitstring on the stack */
0a7de745 A	84	#define bit_decl(name, nbits) \
39236c6e A	85	((name)[bitstr_size(nbits)])
39236c6e A	86
0a7de745 A	87	/* is bit N of bitstring name set? */
0a7de745 A	88	#define bitstr_test(name, bit) \
5ba3f43e	89	((name)[_bitstr_byte(bit)] & _bitstr_mask(bit))
39236c6e	90
0a7de745 A	91	/* set bit N of bitstring name */
0a7de745 A	92	#define bitstr_set(name, bit) \
5ba3f43e	93	((name)[_bitstr_byte(bit)] \|= _bitstr_mask(bit))
39236c6e	94
0a7de745 A	95	/* set bit N of bitstring name (atomic) */
0a7de745 A	96	#define bitstr_set_atomic(name, bit) \
cb323159	97	(void)os_atomic_or(&((name)[_bitstr_byte(bit)]), _bitstr_mask(bit), relaxed)
39236c6e	98
0a7de745 A	99	/* clear bit N of bitstring name */
0a7de745 A	100	#define bitstr_clear(name, bit) \
5ba3f43e	101	((name)[_bitstr_byte(bit)] &= ~_bitstr_mask(bit))
39236c6e	102
0a7de745 A	103	/* clear bit N of bitstring name (atomic) */
0a7de745 A	104	#define bitstr_clear_atomic(name, bit) \
cb323159	105	(void)os_atomic_andnot(&((name)[_bitstr_byte(bit)]), _bitstr_mask(bit), relaxed)
39236c6e	106
0a7de745 A	107	/* clear bits start ... stop in bitstring */
	108	#define bitstr_nclear(name, start, stop) do { \
	109	bitstr_t *_name = (name); \
	110	int _start = (start), _stop = (stop); \
	111	int _startbyte = _bitstr_byte(_start); \
	112	int _stopbyte = _bitstr_byte(_stop); \
	113	if (_startbyte == _stopbyte) { \
	114	_name[_startbyte] &= ((0xff >> (8 - (_start & 0x7))) \| \
	115	(0xff << ((_stop & 0x7) + 1))); \
	116	} else { \
	117	_name[_startbyte] &= 0xff >> (8 - (_start & 0x7)); \
	118	while (++_startbyte < _stopbyte) \
	119	_name[_startbyte] = 0; \
	120	_name[_stopbyte] &= 0xff << ((_stop & 0x7) + 1); \
	121	} \
39236c6e A	122	} while (0)
39236c6e A	123
0a7de745 A	124	/* set bits start ... stop in bitstring */
	125	#define bitstr_nset(name, start, stop) do { \
	126	bitstr_t *_name = (name); \
	127	int _start = (start), _stop = (stop); \
	128	int _startbyte = _bitstr_byte(_start); \
	129	int _stopbyte = _bitstr_byte(_stop); \
	130	if (_startbyte == _stopbyte) { \
	131	_name[_startbyte] \|= ((0xff << (_start & 0x7)) & \
	132	(0xff >> (7 - (_stop & 0x7)))); \
	133	} else { \
	134	_name[_startbyte] \|= 0xff << ((_start) & 0x7); \
	135	while (++_startbyte < _stopbyte) \
	136	_name[_startbyte] = 0xff; \
	137	_name[_stopbyte] \|= 0xff >> (7 - (_stop & 0x7)); \
	138	} \
39236c6e A	139	} while (0)
39236c6e A	140
0a7de745 A	141	/* find first bit clear in name */
	142	#define bitstr_ffc(name, nbits, value) do { \
	143	bitstr_t *_name = (name); \
	144	int _byte, _nbits = (nbits); \
	145	int _stopbyte = _bitstr_byte(_nbits - 1), _value = -1; \
	146	if (_nbits > 0) \
	147	for (_byte = 0; _byte <= _stopbyte; ++_byte) \
	148	if (_name[_byte] != 0xff) { \
	149	bitstr_t _lb; \
	150	_value = _byte << 3; \
	151	for (_lb = _name[_byte]; (_lb & 0x1); \
	152	++_value, _lb >>= 1); \
	153	break; \
	154	} \
	155	if (_value >= nbits) \
	156	_value = -1; \
	157	*(value) = _value; \
39236c6e A	158	} while (0)
39236c6e A	159
0a7de745 A	160	/* find first bit set in name */
	161	#define bitstr_ffs(name, nbits, value) do { \
	162	bitstr_t *_name = (name); \
	163	int _byte, _nbits = (nbits); \
	164	int _stopbyte = _bitstr_byte(_nbits - 1), _value = -1; \
	165	if (_nbits > 0) \
	166	for (_byte = 0; _byte <= _stopbyte; ++_byte) \
	167	if (_name[_byte]) { \
	168	bitstr_t _lb; \
	169	_value = _byte << 3; \
	170	for (_lb = _name[_byte]; !(_lb & 0x1); \
	171	++_value, _lb >>= 1); \
	172	break; \
	173	} \
	174	if (_value >= nbits) \
	175	_value = -1; \
	176	*(value) = _value; \
39236c6e A	177	} while (0)
	178
	179	#endif /* XNU_KERNEL_PRIVATE */
	180	#endif /* !_SYS_BITSTRING_H_ */