NetBSD/dist/pdisk/bitfield.h
dbj a1246c73e0 import pdisk utility from Eryk Vershen:
http://cantaforda.com/cfcl/eryk/linux/pdisk/index.html
this is the utility provided by mklinux and osX to manipulate
the Apple Partition map.
2002-07-09 05:49:02 +00:00

73 lines
2.0 KiB
C

//
// bitfield.h - extract and set bit fields
//
// Written by Eryk Vershen
//
// Bitfields are not particularly transportable between big and little
// endian machines. Big endian machines lay out bitfields starting
// from the most significant bit of the (one, two or four byte) number,
// whereas little endian machines lay out bitfields starting from the
// least signifcant bit.
//
// These routines were written to support some bitfields in a disk
// data structure (partition map) whose original definition was on
// a big-endian machine.
//
// They only work on 32-bit values because I didn't need 16-bit support.
// The bits in the long word are numbered from 0 (least significant) to
// 31 (most significant).
//
/*
* Copyright 1996,1998 by Apple Computer, Inc.
* All Rights Reserved
*
* Permission to use, copy, modify, and distribute this software and
* its documentation for any purpose and without fee is hereby granted,
* provided that the above copyright notice appears in all copies and
* that both the copyright notice and this permission notice appear in
* supporting documentation.
*
* APPLE COMPUTER DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE
* INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE.
*
* IN NO EVENT SHALL APPLE COMPUTER BE LIABLE FOR ANY SPECIAL, INDIRECT, OR
* CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
* LOSS OF USE, DATA OR PROFITS, WHETHER IN ACTION OF CONTRACT,
* NEGLIGENCE, OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
* WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#ifndef __bitfield__
#define __bitfield__
//
// Defines
//
//
// Types
//
//
// Global Constants
//
//
// Global Variables
//
//
// Forward declarations
//
unsigned long bitfield_set(unsigned long *bf, int base, int length, unsigned long value);
unsigned long bitfield_get(unsigned long bf, int base, int length);
#endif /* __bitfield__ */