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Commit	Line	Data
	1	/*
	2	* Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
	3	*
	4	* @APPLE_LICENSE_HEADER_START@
	5	*
	6	* Copyright (c) 1999-2003 Apple Computer, Inc. All Rights Reserved.
	7	*
	8	* This file contains Original Code and/or Modifications of Original Code
	9	* as defined in and that are subject to the Apple Public Source License
	10	* Version 2.0 (the 'License'). You may not use this file except in
	11	* compliance with the License. Please obtain a copy of the License at
	12	* http://www.opensource.apple.com/apsl/ and read it before using this
	13	* file.
	14	*
	15	* The Original Code and all software distributed under the License are
	16	* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
	17	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
	18	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
	19	* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
	20	* Please see the License for the specific language governing rights and
	21	* limitations under the License.
	22	*
	23	* @APPLE_LICENSE_HEADER_END@
	24	*/
	25	/*
	26	* @OSF_COPYRIGHT@
	27	*/
	28	/*
	29	* HISTORY
	30	*
	31	* Revision 1.1.1.1 1998/09/22 21:05:35 wsanchez
	32	* Import of Mac OS X kernel (~semeria)
	33	*
	34	* Revision 1.2 1998/04/29 17:35:55 mburg
	35	* MK7.3 merger
	36	*
	37	* Revision 1.1.24.1 1998/02/03 09:27:19 gdt
	38	* Merge up to MK7.3
	39	* [1998/02/03 09:12:57 gdt]
	40	*
	41	* Revision 1.1.21.1 1996/11/29 16:57:21 stephen
	42	* nmklinux_1.0b3_shared into pmk1.1
	43	* Added explanatory note.
	44	* [1996/04/10 16:54:46 emcmanus]
	45	*
	46	* Revision 1.1.22.1 1997/06/17 02:57:05 devrcs
	47	* Added `testbit()' routine.
	48	* [1996/03/18 15:21:50 rkc]
	49	*
	50	* Revision 1.1.7.3 1995/01/10 05:10:36 devrcs
	51	* mk6 CR801 - copyright marker not FREE_
	52	* [1994/12/01 19:24:54 dwm]
	53	*
	54	* Revision 1.1.7.1 1994/06/14 16:59:49 bolinger
	55	* Merge up to NMK17.2.
	56	* [1994/06/14 16:53:29 bolinger]
	57	*
	58	* Revision 1.1.5.1 1994/04/11 09:36:31 bernadat
	59	* Checked in NMK16_2 revision
	60	* [94/03/15 bernadat]
	61	*
	62	* Revision 1.1.3.1 1993/12/23 08:53:13 bernadat
	63	* Checked in bolinger_860ci revision.
	64	* [93/11/29 bernadat]
	65	*
	66	* Revision 1.1.1.2 1993/09/12 15:44:20 bolinger
	67	* Initial checkin of 860 modifications; MD files from NMK14.8.
	68	*
	69	* $EndLog$
	70	*/
	71	/*
	72	* C version of bit manipulation routines now required by kernel.
	73	* Should be replaced with assembler versions in any real port.
	74	*
	75	* Note that these routines use little-endian numbering for bits (i.e.,
	76	* the bit number corresponds to the associated power-of-2).
	77	*/
	78	#include <mach/machine/vm_param.h> /* for BYTE_SIZE */
	79
	80	#define INT_SIZE (BYTE_SIZE * sizeof (int))
	81
	82	/*
	83	* Set indicated bit in bit string.
	84	*/
	85	void
	86	setbit(int bitno, int *s)
	87	{
	88	for ( ; INT_SIZE <= bitno; bitno -= INT_SIZE, ++s)
	89	;
	90	*s \|= 1 << bitno;
	91	}
	92
	93	/*
	94	* Clear indicated bit in bit string.
	95	*/
	96	void
	97	clrbit(int bitno, int *s)
	98	{
	99	for ( ; INT_SIZE <= bitno; bitno -= INT_SIZE, ++s)
	100	;
	101	*s &= ~(1 << bitno);
	102	}
	103
	104	/*
	105	* Find first bit set in bit string.
	106	*/
	107	int
	108	ffsbit(int *s)
	109	{
	110	int offset, mask;
	111
	112	for (offset = 0; !*s; offset += INT_SIZE, ++s)
	113	;
	114	for (mask = 1; mask; mask <<= 1, ++offset)
	115	if (mask & *s)
	116	return (offset);
	117	/*
	118	* Shouldn't get here
	119	*/
	120	return (0);
	121	}
	122
	123	/*
	124	* Test if indicated bit is set in bit string.
	125	*/
	126	int
	127	testbit(int bitno, int *s)
	128	{
	129	for ( ; INT_SIZE <= bitno; bitno -= INT_SIZE, ++s)
	130	;
	131	return(*s & (1 << bitno));
	132	}