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- /*
- * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
- *
- * @APPLE_LICENSE_HEADER_START@
- *
- * The contents of this file constitute Original Code as defined in and
- * are subject to the Apple Public Source License Version 1.1 (the
- * "License"). You may not use this file except in compliance with the
- * License. Please obtain a copy of the License at
- * http://www.apple.com/publicsource and read it before using this file.
- *
- * This 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 OR NON-INFRINGEMENT. Please see the
- * License for the specific language governing rights and limitations
- * under the License.
- *
- * @APPLE_LICENSE_HEADER_END@
- */
- #ifndef __HFS_FORMAT__
- #define __HFS_FORMAT__
-
- /*
- * hfs_format.c
- *
- * This file describes the on-disk format for HFS and HFS Plus volumes.
- * The HFS Plus volume format is desciibed in detail in Apple Technote 1150.
- *
- * http://developer.apple.com/technotes/tn/tn1150.html
- *
- */
-
- #ifdef __cplusplus
- extern "C" {
- #endif
-
- /* some on-disk hfs structures have 68K alignment (misaligned) */
- #pragma options align=mac68k
-
- /* Signatures used to differentiate between HFS and HFS Plus volumes */
- enum {
- kHFSSigWord = 0x4244, /* 'BD' in ASCII */
- kHFSPlusSigWord = 0x482B, /* 'H+' in ASCII */
- kHFSPlusVersion = 0x0004, /* will change as format changes */
- /* version 4 shipped with Mac OS 8.1 */
- kHFSPlusMountVersion = 0x31302E30 /* '10.0' for Mac OS X */
- };
-
-
- /*
- * Mac OS X has a special directory for linked and unlinked files (HFS Plus only).
- * This directory and its contents are never exported from the filesystem under
- * Mac OS X.
- *
- * To make this folder name sort last, it has embedded null prefix.
- * (0xC0, 0x80 in UTF-8)
- */
- #define HFSPLUSMETADATAFOLDER "\xC0\x80\xC0\x80\xC0\x80\xC0\x80HFS+ Private Data"
-
- /*
- * Files in the HFS Private Data folder have one of the following prefixes
- * followed by a decimal number (no leading zeros). For indirect nodes this
- * number is a 32 bit random number. For unlinked (deleted) files that are
- * still open, the number is the file ID for that file.
- *
- * e.g. iNode7182000 and temp3296
- */
- #define HFS_INODE_PREFIX "iNode"
- #define HFS_DELETE_PREFIX "temp"
-
- /*
- * Indirect link files (hard links) have the following type/creator.
- */
- enum {
- kHardLinkFileType = 0x686C6E6B, /* 'hlnk' */
- kHFSPlusCreator = 0x6866732B /* 'hfs+' */
- };
-
-
- /* Unicode strings are used for HFS Plus file and folder names */
- struct HFSUniStr255 {
- u_int16_t length; /* number of unicode characters */
- u_int16_t unicode[255]; /* unicode characters */
- };
- typedef struct HFSUniStr255 HFSUniStr255;
- typedef const HFSUniStr255 *ConstHFSUniStr255Param;
-
- enum {
- kHFSMaxVolumeNameChars = 27,
- kHFSMaxFileNameChars = 31,
- kHFSPlusMaxFileNameChars = 255
- };
-
-
- /* Extent overflow file data structures */
-
- /* HFS Extent key */
- struct HFSExtentKey {
- u_int8_t keyLength; /* length of key, excluding this field */
- u_int8_t forkType; /* 0 = data fork, FF = resource fork */
- u_int32_t fileID; /* file ID */
- u_int16_t startBlock; /* first file allocation block number in this extent */
- };
- typedef struct HFSExtentKey HFSExtentKey;
-
- /* HFS Plus Extent key */
- struct HFSPlusExtentKey {
- u_int16_t keyLength; /* length of key, excluding this field */
- u_int8_t forkType; /* 0 = data fork, FF = resource fork */
- u_int8_t pad; /* make the other fields align on 32-bit boundary */
- u_int32_t fileID; /* file ID */
- u_int32_t startBlock; /* first file allocation block number in this extent */
- };
- typedef struct HFSPlusExtentKey HFSPlusExtentKey;
-
- /* Number of extent descriptors per extent record */
- enum {
- kHFSExtentDensity = 3,
- kHFSPlusExtentDensity = 8
- };
-
- /* HFS extent descriptor */
- struct HFSExtentDescriptor {
- u_int16_t startBlock; /* first allocation block */
- u_int16_t blockCount; /* number of allocation blocks */
- };
- typedef struct HFSExtentDescriptor HFSExtentDescriptor;
-
- /* HFS Plus extent descriptor */
- struct HFSPlusExtentDescriptor {
- u_int32_t startBlock; /* first allocation block */
- u_int32_t blockCount; /* number of allocation blocks */
- };
- typedef struct HFSPlusExtentDescriptor HFSPlusExtentDescriptor;
-
- /* HFS extent record */
- typedef HFSExtentDescriptor HFSExtentRecord[3];
-
- /* HFS Plus extent record */
- typedef HFSPlusExtentDescriptor HFSPlusExtentRecord[8];
-
-
- /* Finder information */
- struct FndrFileInfo {
- u_int32_t fdType; /* file type */
- u_int32_t fdCreator; /* file creator */
- u_int16_t fdFlags; /* Finder flags */
- struct {
- int16_t v; /* file's location */
- int16_t h;
- } fdLocation;
- int16_t opaque;
- };
- typedef struct FndrFileInfo FndrFileInfo;
-
- struct FndrDirInfo {
- struct { /* folder's window rectangle */
- int16_t top;
- int16_t left;
- int16_t bottom;
- int16_t right;
- } frRect;
- unsigned short frFlags; /* Finder flags */
- struct {
- u_int16_t v; /* folder's location */
- u_int16_t h;
- } frLocation;
- int16_t opaque;
- };
- typedef struct FndrDirInfo FndrDirInfo;
-
- struct FndrOpaqueInfo {
- int8_t opaque[16];
- };
- typedef struct FndrOpaqueInfo FndrOpaqueInfo;
-
-
- /* HFS Plus Fork data info - 80 bytes */
- struct HFSPlusForkData {
- u_int64_t logicalSize; /* fork's logical size in bytes */
- u_int32_t clumpSize; /* fork's clump size in bytes */
- u_int32_t totalBlocks; /* total blocks used by this fork */
- HFSPlusExtentRecord extents; /* initial set of extents */
- };
- typedef struct HFSPlusForkData HFSPlusForkData;
-
-
- /* Mac OS X has 16 bytes worth of "BSD" info.
- *
- * Note: Mac OS 9 implementations and applications
- * should preserve, but not change, this information.
- */
- struct HFSPlusBSDInfo {
- u_int32_t ownerID; /* user or group ID of file/folder owner */
- u_int32_t groupID; /* additional user of group ID */
- u_int8_t adminFlags; /* super-user changeable flags */
- u_int8_t ownerFlags; /* owner changeable flags */
- u_int16_t fileMode; /* file type and permission bits */
- union {
- u_int32_t iNodeNum; /* indirect node number (hard links only) */
- u_int32_t linkCount; /* links that refer to this indirect node */
- u_int32_t rawDevice; /* special file device (FBLK and FCHR only) */
- } special;
- };
- typedef struct HFSPlusBSDInfo HFSPlusBSDInfo;
-
-
- /* Catalog file data structures */
-
- enum {
- kHFSRootParentID = 1, /* Parent ID of the root folder */
- kHFSRootFolderID = 2, /* Folder ID of the root folder */
- kHFSExtentsFileID = 3, /* File ID of the extents file */
- kHFSCatalogFileID = 4, /* File ID of the catalog file */
- kHFSBadBlockFileID = 5, /* File ID of the bad allocation block file */
- kHFSAllocationFileID = 6, /* File ID of the allocation file (HFS Plus only) */
- kHFSStartupFileID = 7, /* File ID of the startup file (HFS Plus only) */
- kHFSAttributesFileID = 8, /* File ID of the attribute file (HFS Plus only) */
- kHFSBogusExtentFileID = 15, /* Used for exchanging extents in extents file */
- kHFSFirstUserCatalogNodeID = 16
- };
-
- /* HFS catalog key */
- struct HFSCatalogKey {
- u_int8_t keyLength; /* key length (in bytes) */
- u_int8_t reserved; /* reserved (set to zero) */
- u_int32_t parentID; /* parent folder ID */
- u_char nodeName[kHFSMaxFileNameChars + 1]; /* catalog node name */
- };
- typedef struct HFSCatalogKey HFSCatalogKey;
-
- /* HFS Plus catalog key */
- struct HFSPlusCatalogKey {
- u_int16_t keyLength; /* key length (in bytes) */
- u_int32_t parentID; /* parent folder ID */
- HFSUniStr255 nodeName; /* catalog node name */
- };
- typedef struct HFSPlusCatalogKey HFSPlusCatalogKey;
-
- /* Catalog record types */
- enum {
- /* HFS Catalog Records */
- kHFSFolderRecord = 0x0100, /* Folder record */
- kHFSFileRecord = 0x0200, /* File record */
- kHFSFolderThreadRecord = 0x0300, /* Folder thread record */
- kHFSFileThreadRecord = 0x0400, /* File thread record */
-
- /* HFS Plus Catalog Records */
- kHFSPlusFolderRecord = 1, /* Folder record */
- kHFSPlusFileRecord = 2, /* File record */
- kHFSPlusFolderThreadRecord = 3, /* Folder thread record */
- kHFSPlusFileThreadRecord = 4 /* File thread record */
- };
-
-
- /* Catalog file record flags */
- enum {
- kHFSFileLockedBit = 0x0000, /* file is locked and cannot be written to */
- kHFSFileLockedMask = 0x0001,
- kHFSThreadExistsBit = 0x0001, /* a file thread record exists for this file */
- kHFSThreadExistsMask = 0x0002
- };
-
-
- /* HFS catalog folder record - 70 bytes */
- struct HFSCatalogFolder {
- int16_t recordType; /* == kHFSFolderRecord */
- u_int16_t flags; /* folder flags */
- u_int16_t valence; /* folder valence */
- u_int32_t folderID; /* folder ID */
- u_int32_t createDate; /* date and time of creation */
- u_int32_t modifyDate; /* date and time of last modification */
- u_int32_t backupDate; /* date and time of last backup */
- FndrDirInfo userInfo; /* Finder information */
- FndrOpaqueInfo finderInfo; /* additional Finder information */
- u_int32_t reserved[4]; /* reserved - initialized as zero */
- };
- typedef struct HFSCatalogFolder HFSCatalogFolder;
-
- /* HFS Plus catalog folder record - 88 bytes */
- struct HFSPlusCatalogFolder {
- int16_t recordType; /* == kHFSPlusFolderRecord */
- u_int16_t flags; /* file flags */
- u_int32_t valence; /* folder's valence (limited to 2^16 in Mac OS) */
- u_int32_t folderID; /* folder ID */
- u_int32_t createDate; /* date and time of creation */
- u_int32_t contentModDate; /* date and time of last content modification */
- u_int32_t attributeModDate; /* date and time of last attribute modification */
- u_int32_t accessDate; /* date and time of last access (MacOS X only) */
- u_int32_t backupDate; /* date and time of last backup */
- HFSPlusBSDInfo bsdInfo; /* permissions (for MacOS X) */
- FndrDirInfo userInfo; /* Finder information */
- FndrOpaqueInfo finderInfo; /* additional Finder information */
- u_int32_t textEncoding; /* hint for name conversions */
- u_int32_t reserved; /* reserved - initialized as zero */
- };
- typedef struct HFSPlusCatalogFolder HFSPlusCatalogFolder;
-
- /* HFS catalog file record - 102 bytes */
- struct HFSCatalogFile {
- int16_t recordType; /* == kHFSFileRecord */
- u_int8_t flags; /* file flags */
- int8_t fileType; /* file type (unused ?) */
- FndrFileInfo userInfo; /* Finder information */
- u_int32_t fileID; /* file ID */
- u_int16_t dataStartBlock; /* not used - set to zero */
- int32_t dataLogicalSize; /* logical EOF of data fork */
- int32_t dataPhysicalSize; /* physical EOF of data fork */
- u_int16_t rsrcStartBlock; /* not used - set to zero */
- int32_t rsrcLogicalSize; /* logical EOF of resource fork */
- int32_t rsrcPhysicalSize; /* physical EOF of resource fork */
- u_int32_t createDate; /* date and time of creation */
- u_int32_t modifyDate; /* date and time of last modification */
- u_int32_t backupDate; /* date and time of last backup */
- FndrOpaqueInfo finderInfo; /* additional Finder information */
- u_int16_t clumpSize; /* file clump size (not used) */
- HFSExtentRecord dataExtents; /* first data fork extent record */
- HFSExtentRecord rsrcExtents; /* first resource fork extent record */
- u_int32_t reserved; /* reserved - initialized as zero */
- };
- typedef struct HFSCatalogFile HFSCatalogFile;
-
- /* HFS Plus catalog file record - 248 bytes */
- struct HFSPlusCatalogFile {
- int16_t recordType; /* == kHFSPlusFileRecord */
- u_int16_t flags; /* file flags */
- u_int32_t reserved1; /* reserved - initialized as zero */
- u_int32_t fileID; /* file ID */
- u_int32_t createDate; /* date and time of creation */
- u_int32_t contentModDate; /* date and time of last content modification */
- u_int32_t attributeModDate; /* date and time of last attribute modification */
- u_int32_t accessDate; /* date and time of last access (MacOS X only) */
- u_int32_t backupDate; /* date and time of last backup */
- HFSPlusBSDInfo bsdInfo; /* permissions (for MacOS X) */
- FndrFileInfo userInfo; /* Finder information */
- FndrOpaqueInfo finderInfo; /* additional Finder information */
- u_int32_t textEncoding; /* hint for name conversions */
- u_int32_t reserved2; /* reserved - initialized as zero */
-
- /* Note: these start on double long (64 bit) boundry */
- HFSPlusForkData dataFork; /* size and block data for data fork */
- HFSPlusForkData resourceFork; /* size and block data for resource fork */
- };
- typedef struct HFSPlusCatalogFile HFSPlusCatalogFile;
-
- /* HFS catalog thread record - 46 bytes */
- struct HFSCatalogThread {
- int16_t recordType; /* == kHFSFolderThreadRecord or kHFSFileThreadRecord */
- int32_t reserved[2]; /* reserved - initialized as zero */
- u_int32_t parentID; /* parent ID for this catalog node */
- u_char nodeName[kHFSMaxFileNameChars + 1]; /* name of this catalog node */
- };
- typedef struct HFSCatalogThread HFSCatalogThread;
-
- /* HFS Plus catalog thread record -- 264 bytes */
- struct HFSPlusCatalogThread {
- int16_t recordType; /* == kHFSPlusFolderThreadRecord or kHFSPlusFileThreadRecord */
- int16_t reserved; /* reserved - initialized as zero */
- u_int32_t parentID; /* parent ID for this catalog node */
- HFSUniStr255 nodeName; /* name of this catalog node (variable length) */
- };
- typedef struct HFSPlusCatalogThread HFSPlusCatalogThread;
-
-
- /*
- These are the types of records in the attribute B-tree. The values were
- chosen so that they wouldn't conflict with the catalog record types.
- */
- enum {
- kHFSPlusAttrInlineData = 0x10, /* if size < kAttrOverflowSize */
- kHFSPlusAttrForkData = 0x20, /* if size >= kAttrOverflowSize */
- kHFSPlusAttrExtents = 0x30 /* overflow extents for large attributes */
- };
-
-
- /*
- HFSPlusAttrInlineData
- For small attributes, whose entire value is stored within this one
- B-tree record.
- There would not be any other records for this attribute.
- */
- struct HFSPlusAttrInlineData {
- u_int32_t recordType; /* == kHFSPlusAttrInlineData*/
- u_int32_t reserved;
- u_int32_t logicalSize; /* size in bytes of userData*/
- u_int8_t userData[2]; /* variable length; space allocated is a multiple of 2 bytes*/
- };
- typedef struct HFSPlusAttrInlineData HFSPlusAttrInlineData;
-
-
- /*
- HFSPlusAttrForkData
- For larger attributes, whose value is stored in allocation blocks.
- If the attribute has more than 8 extents, there will be additonal
- records (of type HFSPlusAttrExtents) for this attribute.
- */
- struct HFSPlusAttrForkData {
- u_int32_t recordType; /* == kHFSPlusAttrForkData*/
- u_int32_t reserved;
- HFSPlusForkData theFork; /* size and first extents of value*/
- };
- typedef struct HFSPlusAttrForkData HFSPlusAttrForkData;
-
- /*
- HFSPlusAttrExtents
- This record contains information about overflow extents for large,
- fragmented attributes.
- */
- struct HFSPlusAttrExtents {
- u_int32_t recordType; /* == kHFSPlusAttrExtents*/
- u_int32_t reserved;
- HFSPlusExtentRecord extents; /* additional extents*/
- };
- typedef struct HFSPlusAttrExtents HFSPlusAttrExtents;
-
- /* A generic Attribute Record*/
- union HFSPlusAttrRecord {
- u_int32_t recordType;
- HFSPlusAttrInlineData inlineData;
- HFSPlusAttrForkData forkData;
- HFSPlusAttrExtents overflowExtents;
- };
- typedef union HFSPlusAttrRecord HFSPlusAttrRecord;
-
- /* Key and node lengths */
- enum {
- kHFSPlusExtentKeyMaximumLength = sizeof(HFSPlusExtentKey) - sizeof(u_int16_t),
- kHFSExtentKeyMaximumLength = sizeof(HFSExtentKey) - sizeof(u_int8_t),
- kHFSPlusCatalogKeyMaximumLength = sizeof(HFSPlusCatalogKey) - sizeof(u_int16_t),
- kHFSPlusCatalogKeyMinimumLength = kHFSPlusCatalogKeyMaximumLength - sizeof(HFSUniStr255) + sizeof(u_int16_t),
- kHFSCatalogKeyMaximumLength = sizeof(HFSCatalogKey) - sizeof(u_int8_t),
- kHFSCatalogKeyMinimumLength = kHFSCatalogKeyMaximumLength - (kHFSMaxFileNameChars + 1) + sizeof(u_int8_t),
- kHFSPlusCatalogMinNodeSize = 4096,
- kHFSPlusExtentMinNodeSize = 512,
- kHFSPlusAttrMinNodeSize = 4096
- };
-
-
- /* HFS and HFS Plus volume attribute bits */
- enum {
- /* Bits 0-6 are reserved (always cleared by MountVol call) */
- kHFSVolumeHardwareLockBit = 7, /* volume is locked by hardware */
- kHFSVolumeUnmountedBit = 8, /* volume was successfully unmounted */
- kHFSVolumeSparedBlocksBit = 9, /* volume has bad blocks spared */
- kHFSVolumeNoCacheRequiredBit = 10, /* don't cache volume blocks (i.e. RAM or ROM disk) */
- kHFSBootVolumeInconsistentBit = 11, /* boot volume is inconsistent (System 7.6 and later) */
- kHFSCatalogNodeIDsReusedBit = 12,
- /* Bits 13-14 are reserved for future use */
- kHFSVolumeSoftwareLockBit = 15, /* volume is locked by software */
-
- kHFSVolumeHardwareLockMask = 1 << kHFSVolumeHardwareLockBit,
- kHFSVolumeUnmountedMask = 1 << kHFSVolumeUnmountedBit,
- kHFSVolumeSparedBlocksMask = 1 << kHFSVolumeSparedBlocksBit,
- kHFSVolumeNoCacheRequiredMask = 1 << kHFSVolumeNoCacheRequiredBit,
- kHFSBootVolumeInconsistentMask = 1 << kHFSBootVolumeInconsistentBit,
- kHFSCatalogNodeIDsReusedMask = 1 << kHFSCatalogNodeIDsReusedBit,
- kHFSVolumeSoftwareLockMask = 1 << kHFSVolumeSoftwareLockBit,
- kHFSMDBAttributesMask = 0x8380
- };
-
-
- /* HFS Master Directory Block - 162 bytes */
- /* Stored at sector #2 (3rd sector) and second-to-last sector. */
- struct HFSMasterDirectoryBlock {
- u_int16_t drSigWord; /* == kHFSSigWord */
- u_int32_t drCrDate; /* date and time of volume creation */
- u_int32_t drLsMod; /* date and time of last modification */
- u_int16_t drAtrb; /* volume attributes */
- u_int16_t drNmFls; /* number of files in root folder */
- u_int16_t drVBMSt; /* first block of volume bitmap */
- u_int16_t drAllocPtr; /* start of next allocation search */
- u_int16_t drNmAlBlks; /* number of allocation blocks in volume */
- u_int32_t drAlBlkSiz; /* size (in bytes) of allocation blocks */
- u_int32_t drClpSiz; /* default clump size */
- u_int16_t drAlBlSt; /* first allocation block in volume */
- u_int32_t drNxtCNID; /* next unused catalog node ID */
- u_int16_t drFreeBks; /* number of unused allocation blocks */
- u_char drVN[kHFSMaxVolumeNameChars + 1]; /* volume name */
- u_int32_t drVolBkUp; /* date and time of last backup */
- u_int16_t drVSeqNum; /* volume backup sequence number */
- u_int32_t drWrCnt; /* volume write count */
- u_int32_t drXTClpSiz; /* clump size for extents overflow file */
- u_int32_t drCTClpSiz; /* clump size for catalog file */
- u_int16_t drNmRtDirs; /* number of directories in root folder */
- u_int32_t drFilCnt; /* number of files in volume */
- u_int32_t drDirCnt; /* number of directories in volume */
- u_int32_t drFndrInfo[8]; /* information used by the Finder */
- u_int16_t drEmbedSigWord; /* embedded volume signature (formerly drVCSize) */
- HFSExtentDescriptor drEmbedExtent; /* embedded volume location and size (formerly drVBMCSize and drCtlCSize) */
- u_int32_t drXTFlSize; /* size of extents overflow file */
- HFSExtentRecord drXTExtRec; /* extent record for extents overflow file */
- u_int32_t drCTFlSize; /* size of catalog file */
- HFSExtentRecord drCTExtRec; /* extent record for catalog file */
- };
- typedef struct HFSMasterDirectoryBlock HFSMasterDirectoryBlock;
-
-
- /* HFS Plus Volume Header - 512 bytes */
- /* Stored at sector #2 (3rd sector) and second-to-last sector. */
- struct HFSPlusVolumeHeader {
- u_int16_t signature; /* == kHFSPlusSigWord */
- u_int16_t version; /* == kHFSPlusVersion */
- u_int32_t attributes; /* volume attributes */
- u_int32_t lastMountedVersion; /* implementation version which last mounted volume */
- u_int32_t reserved; /* reserved - initialized as zero */
-
- u_int32_t createDate; /* date and time of volume creation */
- u_int32_t modifyDate; /* date and time of last modification */
- u_int32_t backupDate; /* date and time of last backup */
- u_int32_t checkedDate; /* date and time of last disk check */
-
- u_int32_t fileCount; /* number of files in volume */
- u_int32_t folderCount; /* number of directories in volume */
-
- u_int32_t blockSize; /* size (in bytes) of allocation blocks */
- u_int32_t totalBlocks; /* number of allocation blocks in volume (includes this header and VBM*/
- u_int32_t freeBlocks; /* number of unused allocation blocks */
-
- u_int32_t nextAllocation; /* start of next allocation search */
- u_int32_t rsrcClumpSize; /* default resource fork clump size */
- u_int32_t dataClumpSize; /* default data fork clump size */
- u_int32_t nextCatalogID; /* next unused catalog node ID */
-
- u_int32_t writeCount; /* volume write count */
- u_int64_t encodingsBitmap; /* which encodings have been use on this volume */
-
- u_int8_t finderInfo[32]; /* information used by the Finder */
-
- HFSPlusForkData allocationFile; /* allocation bitmap file */
- HFSPlusForkData extentsFile; /* extents B-tree file */
- HFSPlusForkData catalogFile; /* catalog B-tree file */
- HFSPlusForkData attributesFile; /* extended attributes B-tree file */
- HFSPlusForkData startupFile; /* boot file (secondary loader) */
- };
- typedef struct HFSPlusVolumeHeader HFSPlusVolumeHeader;
-
-
- /* B-tree structures */
-
- enum BTreeKeyLimits{
- kMaxKeyLength = 520
- };
-
- union BTreeKey{
- u_int8_t length8;
- u_int16_t length16;
- u_int8_t rawData [kMaxKeyLength+2];
- };
- typedef union BTreeKey BTreeKey;
-
- /* BTNodeDescriptor -- Every B-tree node starts with these fields. */
- struct BTNodeDescriptor {
- u_int32_t fLink; /* next node at this level*/
- u_int32_t bLink; /* previous node at this level*/
- int8_t kind; /* kind of node (leaf, index, header, map)*/
- u_int8_t height; /* zero for header, map; child is one more than parent*/
- u_int16_t numRecords; /* number of records in this node*/
- u_int16_t reserved; /* reserved - initialized as zero */
- };
- typedef struct BTNodeDescriptor BTNodeDescriptor;
-
- /* Constants for BTNodeDescriptor kind */
- enum {
- kBTLeafNode = -1,
- kBTIndexNode = 0,
- kBTHeaderNode = 1,
- kBTMapNode = 2
- };
-
- /* BTHeaderRec -- The first record of a B-tree header node */
- struct BTHeaderRec {
- u_int16_t treeDepth; /* maximum height (usually leaf nodes) */
- u_int32_t rootNode; /* node number of root node */
- u_int32_t leafRecords; /* number of leaf records in all leaf nodes */
- u_int32_t firstLeafNode; /* node number of first leaf node */
- u_int32_t lastLeafNode; /* node number of last leaf node */
- u_int16_t nodeSize; /* size of a node, in bytes */
- u_int16_t maxKeyLength; /* reserved */
- u_int32_t totalNodes; /* total number of nodes in tree */
- u_int32_t freeNodes; /* number of unused (free) nodes in tree */
- u_int16_t reserved1; /* unused */
- u_int32_t clumpSize; /* reserved */
- u_int8_t btreeType; /* reserved */
- u_int8_t reserved2; /* reserved */
- u_int32_t attributes; /* persistent attributes about the tree */
- u_int32_t reserved3[16]; /* reserved */
- };
- typedef struct BTHeaderRec BTHeaderRec;
-
- /* Constants for BTHeaderRec attributes */
- enum {
- kBTBadCloseMask = 0x00000001, /* reserved */
- kBTBigKeysMask = 0x00000002, /* key length field is 16 bits */
- kBTVariableIndexKeysMask = 0x00000004 /* keys in index nodes are variable length */
- };
-
- #pragma options align=reset
-
- #ifdef __cplusplus
- }
- #endif
-
- #endif /* __HFS_FORMAT__ */
-