git.saurik.com Git - apple/xnu.git/blame_incremental

... / ...

Commit	Line	Data
	1	/*
	2	* Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
	3	*
	4	* @APPLE_LICENSE_HEADER_START@
	5	*
	6	* The contents of this file constitute Original Code as defined in and
	7	* are subject to the Apple Public Source License Version 1.1 (the
	8	* "License"). You may not use this file except in compliance with the
	9	* License. Please obtain a copy of the License at
	10	* http://www.apple.com/publicsource and read it before using this file.
	11	*
	12	* This Original Code and all software distributed under the License are
	13	* distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
	14	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
	15	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
	16	* FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the
	17	* License for the specific language governing rights and limitations
	18	* under the License.
	19	*
	20	* @APPLE_LICENSE_HEADER_END@
	21	*/
	22	#ifndef __HFS_ENDIAN_H__
	23	#define __HFS_ENDIAN_H__
	24
	25	#include <sys/appleapiopts.h>
	26
	27	#ifdef KERNEL
	28	#ifdef __APPLE_API_PRIVATE
	29	/*
	30	* hfs_endian.h
	31	*
	32	* This file prototypes endian swapping routines for the HFS/HFS Plus
	33	* volume format.
	34	*/
	35	#include "hfs.h"
	36	#include "hfscommon/headers/BTreesInternal.h"
	37	#include <architecture/byte_order.h>
	38
	39	/*********************/
	40	/* BIG ENDIAN Macros */
	41	/*********************/
	42	#if BYTE_ORDER == BIG_ENDIAN
	43
	44	/* HFS is always big endian, make swaps into no-ops */
	45	#define SWAP_BE16(__a) (__a)
	46	#define SWAP_BE32(__a) (__a)
	47	#define SWAP_BE64(__a) (__a)
	48
	49	/* HFS is always big endian, no swapping needed */
	50	#define SWAP_HFS_PLUS_FORK_DATA(__a)
	51
	52	/************************/
	53	/* LITTLE ENDIAN Macros */
	54	/************************/
	55	#elif BYTE_ORDER == LITTLE_ENDIAN
	56
	57	/* HFS is always big endian, make swaps actually swap */
	58	#define SWAP_BE16(__a) NXSwapBigShortToHost (__a)
	59	#define SWAP_BE32(__a) NXSwapBigLongToHost (__a)
	60	#define SWAP_BE64(__a) NXSwapBigLongLongToHost (__a)
	61
	62	#define SWAP_HFS_PLUS_FORK_DATA(__a) hfs_swap_HFSPlusForkData ((__a))
	63
	64	#else
	65	#warning Unknown byte order
	66	#error
	67	#endif
	68
	69	#ifdef __cplusplus
	70	extern "C" {
	71	#endif
	72
	73	/*
	74	* Constants for the "unswap" argument to hfs_swap_BTNode:
	75	*/
	76	enum HFSBTSwapDirection {
	77	kSwapBTNodeBigToHost = 0,
	78	kSwapBTNodeHostToBig = 1,
	79
	80	/*
	81	* kSwapBTNodeHeaderRecordOnly is used to swap just the header record
	82	* of a header node from big endian (on disk) to host endian (in memory).
	83	* It does not swap the node descriptor (forward/backward links, record
	84	* count, etc.). It assumes the header record is at offset 0x000E.
	85	*
	86	* Since HFS Plus doesn't have fixed B-tree node sizes, we have to read
	87	* the header record to determine the actual node size for that tree
	88	* before we can set up the B-tree control block. We read it initially
	89	* as 512 bytes, then re-read it once we know the correct node size. Since
	90	* we may not have read the entire header node the first time, we can't
	91	* swap the record offsets, other records, or do most sanity checks.
	92	*/
	93	kSwapBTNodeHeaderRecordOnly = 3
	94	};
	95
	96	int hfs_swap_BTNode (BlockDescriptor *src, vnode_t vp, enum HFSBTSwapDirection direction);
	97
	98	#ifdef __cplusplus
	99	}
	100	#endif
	101
	102	#endif /* __APPLE_API_PRIVATE */
	103	#endif /* KERNEL */
	104	#endif /* __HFS_FORMAT__ */