1//
2// bitfield.h - extract and set bit fields
3//
4// Written by Eryk Vershen
5//
6// Bitfields are not particularly transportable between big and little
7// endian machines.  Big endian machines lay out bitfields starting
8// from the most significant bit of the (one, two or four byte) number,
9// whereas little endian machines lay out bitfields starting from the
10// least signifcant bit.
11//
12// These routines were written to support some bitfields in a disk
13// data structure (partition map) whose original definition was on
14// a big-endian machine.
15//
16// They only work on 32-bit values because I didn't need 16-bit support.
17// The bits in the long word are numbered from 0 (least significant) to
18// 31 (most significant).
19//
20
21/*
22 * Copyright 1996,1998 by Apple Computer, Inc.
23 *              All Rights Reserved
24 *
25 * Permission to use, copy, modify, and distribute this software and
26 * its documentation for any purpose and without fee is hereby granted,
27 * provided that the above copyright notice appears in all copies and
28 * that both the copyright notice and this permission notice appear in
29 * supporting documentation.
30 *
31 * APPLE COMPUTER DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE
32 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
33 * FOR A PARTICULAR PURPOSE.
34 *
35 * IN NO EVENT SHALL APPLE COMPUTER BE LIABLE FOR ANY SPECIAL, INDIRECT, OR
36 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
37 * LOSS OF USE, DATA OR PROFITS, WHETHER IN ACTION OF CONTRACT,
38 * NEGLIGENCE, OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
39 * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
40 */
41
42#ifndef __bitfield__
43#define __bitfield__
44
45
46//
47// Defines
48//
49
50
51//
52// Types
53//
54
55
56//
57// Global Constants
58//
59
60
61//
62// Global Variables
63//
64
65
66//
67// Forward declarations
68//
69unsigned int bitfield_set(unsigned int *bf, int base, int length, unsigned int value);
70unsigned int bitfield_get(unsigned int bf, int base, int length);
71
72#endif /* __bitfield__ */
73