bsd/hfs/hfscommon/headers/BTreesPrivate.h

   1 /*
   2  * Copyright (c) 2000-2003 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 /*
  23         File:           BTreesPrivate.h
  24
  25         Contains:       Private interface file for the BTree Module.
  26
  27         Version:        xxx put the technology version here xxx
  28
  29         Written by:     Gordon Sheridan and Bill Bruffey
  30
  31         Copyright:      © 1992-1999 by Apple Computer, Inc., all rights reserved.
  32
  33         File Ownership:
  34
  35                 DRI:                            Don Brady
  36
  37                 Other Contact:          Mark Day
  38
  39                 Technology:                     File Systems
  40
  41         Writers:
  42
  43                 (msd)   Mark Day
  44                 (DSH)   Deric Horn
  45                 (djb)   Don Brady
  46                 (ser)   Scott Roberts
  47                 (dkh)   Dave Heller
  48
  49         Change History (most recent first):
  50            <MacOSX>      3/19/99        djb             Disable MoveRecordsLeft/Right macros since bcopy is broken.
  51
  52            <MacOSX>      8/10/98        djb             Removed unused BTreeIterator from BTreeControlBlock, fixed alignment.
  53
  54            <CS5>          9/4/97        djb             Convert MoveRecordsLeft and GetLeftSiblingNode to macros.
  55            <CS4>         7/24/97        djb             Add macro for GetRecordAddress (was a function before).
  56            <CS3>         7/21/97        msd             GetRecordByIndex now returns an OSStatus.
  57            <CS2>         7/16/97        DSH             FilesInternal.i renamed FileMgrInternal.i to avoid name
  58                                                                         collision
  59            <CS1>         4/23/97        djb             first checked in
  60
  61           <HFS6>         3/17/97        DSH             Added a refCon field to BTreeControlBlock, for DFA use, to point
  62                                                                         to additional data.  Fixed Panic macros for use with SC.
  63           <HFS5>         2/19/97        djb             Add InsertKey struct. Moved on-disk definitions to
  64                                                                         HFSBTreesPriv.h
  65           <HFS4>         1/27/97        djb             InsertTree and DeleteTree are now recursive and support variable
  66                                                                         sized index keys.
  67           <HFS3>         1/15/97        djb             Move GetFileRefNumFromFCB macro to FilesInternal.h. Added
  68                                                                         kBTVariableIndexKeysMask.
  69           <HFS2>          1/3/97        djb             Added support for large keys.
  70           <HFS1>        12/19/96        djb             first checked in
  71
  72         History applicable to original Scarecrow Design:
  73
  74                  <7>    10/25/96        ser             Changing for new VFPI
  75                  <6>    10/18/96        ser             Converting over VFPI changes
  76                  <5>     9/17/96        dkh             More BTree statistics
  77                  <4>     9/16/96        dkh             Revised BTree statistics
  78                  <3>     6/20/96        dkh             Radar #1358740. Switch from using Pools to debug MemAllocators.
  79                  <2>     12/7/95        dkh             D10E2 build. Changed usage of Ref data type to LogicalAddress.
  80                  <1>    10/18/95        rst             Moved from Scarecrow project.
  81
  82                 <19>    11/22/94        djb             Add prototype for GetMapNode
  83                 <18>    11/16/94        prp             Add IsItAHint routine prototype.
  84                 <17>     9/30/94        prp             Get in sync with D2 interface changes.
  85                 <16>     7/25/94        wjk             Eliminate usage of BytePtr in favor of UInt8 *.
  86                 <15>     7/22/94        wjk             Convert to the new set of header files.
  87                 <14>     5/31/94        srs             Moved Btree types to public interface
  88                 <13>     12/9/93        wjk             Add 68k alignment pragma's around persistent structures.
  89                 <12>    11/30/93        wjk             Move from Makefiles to BuildFiles. Fit into the ModernOS and
  90                                                                         NRCmds environments.
  91                 <11>    11/23/93        wjk             Changes required to compile on the RS6000.
  92                 <10>     8/30/93        CH              Removed the M_ExitOnError and M_ReturnErrorIf macros which were
  93                                                                         already defined in FileSystemPriv.h (included here).
  94                  <9>     8/30/93        CH              Added parens around the M_ReturnErrorIf macro.
  95                  <8>     5/21/93        gs              Add kBadClose flag. Add some prototypes for internal routines.
  96                  <7>     5/10/93        gs              Change Ptr to BytePtr. Move BTreeTypes to BTree.h. Add
  97                                                                         DeleteTree prototype.
  98                  <6>     3/23/93        gs              Remove mysterious "flags" field from HeaderRec structure. Move
  99                                                                         prototypes of private functions to top of respective source
 100                                                                         files.
 101                  <5>      2/8/93        gs              Update to use FSAgent.h Get/Release/SetEOF/SetBlockSize
 102                                                                         procPtrs. Add UpdateNode routine.
 103                  <4>    12/10/92        gs              Add Key Descriptor function declarations.
 104                  <3>     12/8/92        gs              Add HeaderRec structure and incorporate review feedback.
 105                  <2>     12/2/92        gs              Add GetNode and ReleaseNode callback procptrs to BTree CB, and
 106                                                                         add internal function declarations.
 107                  <1>    11/15/92        gs              first checked in
 108
 109 */
 110
 111 #ifndef __BTREESPRIVATE__
 112 #define __BTREESPRIVATE__
 113
 114 #include <sys/appleapiopts.h>
 115
 116 #ifdef KERNEL
 117 #ifdef __APPLE_API_PRIVATE
 118
 119 #include "../../hfs_macos_defs.h"
 120
 121 #ifndef __FILEMGRINTERNAL__
 122 #include "FileMgrInternal.h"
 123 #endif
 124
 125 #ifndef __BTREESINTERNAL__
 126 #include "BTreesInternal.h"
 127 #endif
 128
 129
 130 /////////////////////////////////// Constants ///////////////////////////////////
 131
 132 #define         kBTreeVersion             1
 133 #define         kMaxTreeDepth            16
 134
 135
 136 #define         kHeaderNodeNum            0
 137 #define         kKeyDescRecord            1
 138
 139
 140 // Header Node Record Offsets
 141 enum {
 142         kHeaderRecOffset        =       0x000E,
 143         kKeyDescRecOffset       =       0x0078,
 144         kHeaderMapRecOffset     =       0x00F8
 145 };
 146
 147 #define         kMinNodeSize            512
 148
 149 #define         kMinRecordSize            6
 150                                                                                 // where is minimum record size enforced?
 151
 152 // miscellaneous BTree constants
 153 enum {
 154                         kOffsetSize                             = 2
 155 };
 156
 157 // Insert Operations
 158 typedef enum {
 159                         kInsertRecord                   = 0,
 160                         kReplaceRecord                  = 1
 161 } InsertType;
 162
 163 // illegal string attribute bits set in mask
 164 #define         kBadStrAttribMask               0xCF
 165
 166
 167
 168 //////////////////////////////////// Macros /////////////////////////////////////
 169
 170 #define         M_NodesInMap(mapSize)                           ((mapSize) << 3)
 171
 172 #define         M_ClearBitNum(integer,bitNumber)        ((integer) &= (~(1<<(bitNumber))))
 173 #define         M_SetBitNum(integer,bitNumber)          ((integer) |= (1<<(bitNumber)))
 174 #define         M_IsOdd(integer)                                        (((integer) & 1) != 0)
 175 #define         M_IsEven(integer)                                       (((integer) & 1) == 0)
 176 #define         M_BTreeHeaderDirty(btreePtr)            btreePtr->flags |= kBTHeaderDirty
 177
 178 #define         M_MapRecordSize(nodeSize)                       (nodeSize - sizeof (BTNodeDescriptor) - 6)
 179 #define         M_HeaderMapRecordSize(nodeSize)         (nodeSize - sizeof(BTNodeDescriptor) - sizeof(BTHeaderRec) - 128 - 8)
 180
 181 #define         M_SWAP_BE16_ClearBitNum(integer,bitNumber)  ((integer) &= SWAP_BE16(~(1<<(bitNumber))))
 182 #define         M_SWAP_BE16_SetBitNum(integer,bitNumber)    ((integer) |= SWAP_BE16(1<<(bitNumber)))
 183
 184 ///////////////////////////////////// Types /////////////////////////////////////
 185
 186 typedef struct BTreeControlBlock {                                      // fields specific to BTree CBs
 187
 188         UInt8           keyCompareType;   /* Key string Comparison Type */
 189         UInt8                                            btreeType;
 190         UInt16                                           treeDepth;
 191         FileReference                            fileRefNum;            // refNum of btree file
 192         KeyCompareProcPtr                        keyCompareProc;
 193         UInt32                                           rootNode;
 194         UInt32                                           leafRecords;
 195         UInt32                                           firstLeafNode;
 196         UInt32                                           lastLeafNode;
 197         UInt16                                           nodeSize;
 198         UInt16                                           maxKeyLength;
 199         UInt32                                           totalNodes;
 200         UInt32                                           freeNodes;
 201
 202         UInt16                                           reserved3;                     // 4-byte alignment
 203
 204         // new fields
 205         SInt16                                           version;
 206         UInt32                                           flags;                         // dynamic flags
 207         UInt32                                           attributes;            // persistent flags
 208         UInt32                                           writeCount;
 209         UInt32                                           lastfsync;             /* Last time that this was fsynced  */
 210
 211         GetBlockProcPtr                          getBlockProc;
 212         ReleaseBlockProcPtr                      releaseBlockProc;
 213         SetEndOfForkProcPtr                      setEndOfForkProc;
 214
 215         // statistical information
 216         UInt32                                           numGetNodes;
 217         UInt32                                           numGetNewNodes;
 218         UInt32                                           numReleaseNodes;
 219         UInt32                                           numUpdateNodes;
 220         UInt32                                           numMapNodesRead;       // map nodes beyond header node
 221         UInt32                                           numHintChecks;
 222         UInt32                                           numPossibleHints;      // Looks like a formated hint
 223         UInt32                                           numValidHints;         // Hint used to find correct record.
 224         UInt32                                  reservedNodes;
 225 } BTreeControlBlock, *BTreeControlBlockPtr;
 226
 227
 228 UInt32 CalcKeySize(const BTreeControlBlock *btcb, const BTreeKey *key);
 229 #define CalcKeySize(btcb, key)                  ( ((btcb)->attributes & kBTBigKeysMask) ? ((key)->length16 + 2) : ((key)->length8 + 1) )
 230
 231 UInt32 KeyLength(const BTreeControlBlock *btcb, const BTreeKey *key);
 232 #define KeyLength(btcb, key)                    ( ((btcb)->attributes & kBTBigKeysMask) ? (key)->length16 : (key)->length8 )
 233
 234
 235
 236 typedef enum {
 237                                         kBTHeaderDirty  = 0x00000001
 238 }       BTreeFlags;
 239
 240
 241 typedef SInt8                           *NodeBuffer;
 242 typedef BlockDescriptor          NodeRec, *NodePtr;             //\80\80 remove this someday...
 243
 244
 245
 246
 247 //// Tree Path Table - constructed by SearchTree, used by InsertTree and DeleteTree
 248
 249 typedef struct {
 250         UInt32                          node;                           // node number
 251         UInt16                          index;
 252         UInt16                          reserved;                       // align size to a power of 2
 253 } TreePathRecord, *TreePathRecordPtr;
 254
 255 typedef TreePathRecord          TreePathTable [kMaxTreeDepth];
 256
 257
 258 //// InsertKey - used by InsertTree, InsertLevel and InsertNode
 259
 260 struct InsertKey {
 261         BTreeKeyPtr             keyPtr;
 262         UInt8 *                 recPtr;
 263         UInt16                  keyLength;
 264         UInt16                  recSize;
 265         Boolean                 replacingKey;
 266         Boolean                 skipRotate;
 267 };
 268
 269 typedef struct InsertKey InsertKey;
 270
 271
 272 //// For Notational Convenience
 273
 274 typedef BTNodeDescriptor*        NodeDescPtr;
 275 typedef UInt8                           *RecordPtr;
 276 typedef BTreeKeyPtr                      KeyPtr;
 277
 278
 279 //////////////////////////////////// Globals ////////////////////////////////////
 280
 281
 282 //////////////////////////////////// Macros /////////////////////////////////////
 283
 284 #if DEBUG_BUILD
 285         #define Panic( message )                                        DebugStr( (ConstStr255Param) message )
 286         #define PanicIf( condition, message )           if ( condition != 0 )   DebugStr( message )
 287 #else
 288         #define Panic( message )
 289         #define PanicIf( condition, message )
 290 #endif
 291
 292 //      Exit function on error
 293 #define M_ExitOnError( result ) if ( ( result ) != noErr )      goto ErrorExit; else ;
 294
 295 //      Test for passed condition and return if true
 296 #define M_ReturnErrorIf( condition, error )     if ( condition )        return( error )
 297
 298 //////////////////////////////// Key Operations /////////////////////////////////
 299
 300 SInt32          CompareKeys                             (BTreeControlBlockPtr    btreePtr,
 301                                                                          KeyPtr                                  searchKey,
 302                                                                          KeyPtr                                  trialKey );
 303
 304 //////////////////////////////// Map Operations /////////////////////////////////
 305
 306 OSStatus        AllocateNode                    (BTreeControlBlockPtr    btreePtr,
 307                                                                          UInt32                                 *nodeNum);
 308
 309 OSStatus        FreeNode                                (BTreeControlBlockPtr    btreePtr,
 310                                                                          UInt32                                  nodeNum);
 311
 312 OSStatus        ExtendBTree                             (BTreeControlBlockPtr    btreePtr,
 313                                                                          UInt32                                  nodes );
 314
 315 UInt32          CalcMapBits                             (BTreeControlBlockPtr    btreePtr);
 316
 317 SInt32          BTAvailableNodes                        (BTreeControlBlock *btree);
 318
 319 void            BTUpdateReserve                         (BTreeControlBlockPtr btreePtr,
 320                                                          int nodes);
 321
 322 //////////////////////////////// Misc Operations ////////////////////////////////
 323
 324 UInt16          CalcKeyRecordSize               (UInt16                                  keySize,
 325                                                                          UInt16                                  recSize );
 326
 327 OSStatus        VerifyHeader                    (FCB                                    *filePtr,
 328                                                                          BTHeaderRec                            *header );
 329
 330 OSStatus        UpdateHeader                    (BTreeControlBlockPtr    btreePtr,
 331                                                  Boolean forceWrite );
 332
 333 OSStatus        FindIteratorPosition    (BTreeControlBlockPtr    btreePtr,
 334                                                                          BTreeIteratorPtr                iterator,
 335                                                                          BlockDescriptor                *left,
 336                                                                          BlockDescriptor                *middle,
 337                                                                          BlockDescriptor                *right,
 338                                                                          UInt32                                 *nodeNum,
 339                                                                          UInt16                                 *index,
 340                                                                          Boolean                                *foundRecord );
 341
 342 OSStatus        CheckInsertParams               (FCB                                    *filePtr,
 343                                                                          BTreeIterator                  *iterator,
 344                                                                          FSBufferDescriptor             *record,
 345                                                                          UInt16                                  recordLen );
 346
 347 OSStatus        TrySimpleReplace                (BTreeControlBlockPtr    btreePtr,
 348                                                                          NodeDescPtr                     nodePtr,
 349                                                                          BTreeIterator                  *iterator,
 350                                                                          FSBufferDescriptor             *record,
 351                                                                          UInt16                                  recordLen,
 352                                                                          Boolean                                *recordInserted );
 353
 354 OSStatus        IsItAHint                               (BTreeControlBlockPtr    btreePtr,
 355                                                                          BTreeIterator                  *iterator,
 356                                                                          Boolean                                *answer );
 357
 358 //////////////////////////////// Node Operations ////////////////////////////////
 359
 360 //// Node Operations
 361
 362 OSStatus        GetNode                                 (BTreeControlBlockPtr    btreePtr,
 363                                                                          UInt32                                  nodeNum,
 364                                                                          NodeRec                                *returnNodePtr );
 365
 366 OSStatus        GetLeftSiblingNode              (BTreeControlBlockPtr    btreePtr,
 367                                                                          NodeDescPtr                     node,
 368                                                                          NodeRec                                *left );
 369
 370 #define         GetLeftSiblingNode(btree,node,left)                     GetNode ((btree), ((NodeDescPtr)(node))->bLink, (left))
 371
 372 OSStatus        GetRightSiblingNode             (BTreeControlBlockPtr    btreePtr,
 373                                                                          NodeDescPtr                     node,
 374                                                                          NodeRec                                *right );
 375
 376 #define         GetRightSiblingNode(btree,node,right)           GetNode ((btree), ((NodeDescPtr)(node))->fLink, (right))
 377
 378
 379 OSStatus        GetNewNode                              (BTreeControlBlockPtr    btreePtr,
 380                                                                          UInt32                                  nodeNum,
 381                                                                          NodeRec                                *returnNodePtr );
 382
 383 OSStatus        ReleaseNode                             (BTreeControlBlockPtr    btreePtr,
 384                                                                          NodePtr                                 nodePtr );
 385
 386 OSStatus        TrashNode                               (BTreeControlBlockPtr    btreePtr,
 387                                                                          NodePtr                                 nodePtr );
 388
 389 // XXXdbg
 390 void ModifyBlockStart(FileReference vp, BlockDescPtr blockPtr);
 391 // XXXdbg
 392
 393 OSStatus        UpdateNode                              (BTreeControlBlockPtr    btreePtr,
 394                                                                          NodePtr                                 nodePtr,
 395                                                                          UInt32                                  transactionID,
 396                                                                          UInt32                                  flags );
 397
 398 OSStatus        GetMapNode                              (BTreeControlBlockPtr    btreePtr,
 399                                                                          BlockDescriptor                 *nodePtr,
 400                                                                          UInt16                                  **mapPtr,
 401                                                                          UInt16                                  *mapSize );
 402
 403 //// Node Buffer Operations
 404
 405 void            ClearNode                               (BTreeControlBlockPtr    btreePtr,
 406                                                                          NodeDescPtr                     node );
 407
 408 UInt16          GetNodeDataSize                 (BTreeControlBlockPtr    btreePtr,
 409                                                                          NodeDescPtr                     node );
 410
 411 UInt16          GetNodeFreeSize                 (BTreeControlBlockPtr    btreePtr,
 412                                                                          NodeDescPtr                     node );
 413
 414
 415 //// Record Operations
 416
 417 Boolean         InsertRecord                    (BTreeControlBlockPtr    btreePtr,
 418                                                                          NodeDescPtr                     node,
 419                                                                          UInt16                                  index,
 420                                                                          RecordPtr                               recPtr,
 421                                                                          UInt16                                  recSize );
 422
 423 Boolean         InsertKeyRecord                 (BTreeControlBlockPtr    btreePtr,
 424                                                                          NodeDescPtr                     node,
 425                                                                          UInt16                                  index,
 426                                                                          KeyPtr                                  keyPtr,
 427                                                                          UInt16                                  keyLength,
 428                                                                          RecordPtr                               recPtr,
 429                                                                          UInt16                                  recSize );
 430
 431 void            DeleteRecord                    (BTreeControlBlockPtr   btree,
 432                                                                          NodeDescPtr                    node,
 433                                                                          UInt16                                 index );
 434
 435
 436 Boolean         SearchNode                              (BTreeControlBlockPtr    btree,
 437                                                                          NodeDescPtr                     node,
 438                                                                          KeyPtr                                  searchKey,
 439                                                                          UInt16                                 *index );
 440
 441 OSStatus        GetRecordByIndex                (BTreeControlBlockPtr    btree,
 442                                                                          NodeDescPtr                     node,
 443                                                                          UInt16                                  index,
 444                                                                          KeyPtr                                 *keyPtr,
 445                                                                          UInt8 *                                *dataPtr,
 446                                                                          UInt16                                 *dataSize );
 447
 448 UInt8 *         GetRecordAddress                (BTreeControlBlockPtr    btree,
 449                                                                          NodeDescPtr                     node,
 450                                                                          UInt16                                  index );
 451
 452 #define GetRecordAddress(btreePtr,node,index)           ((UInt8 *)(node) + (*(short *) ((UInt8 *)(node) + (btreePtr)->nodeSize - ((index) << 1) - kOffsetSize)))
 453
 454
 455 UInt16          GetRecordSize                   (BTreeControlBlockPtr    btree,
 456                                                                          NodeDescPtr                     node,
 457                                                                          UInt16                                  index );
 458
 459 UInt32          GetChildNodeNum                 (BTreeControlBlockPtr    btreePtr,
 460                                                                          NodeDescPtr                     nodePtr,
 461                                                                          UInt16                                  index );
 462
 463 void            MoveRecordsLeft                 (UInt8 *                                 src,
 464                                                                          UInt8 *                                 dst,
 465                                                                          UInt16                                  bytesToMove );
 466
 467 #define         MoveRecordsLeft(src,dst,bytes)                  bcopy((src),(dst),(bytes))
 468
 469 void            MoveRecordsRight                (UInt8 *                                 src,
 470                                                                          UInt8 *                                 dst,
 471                                                                          UInt16                                  bytesToMove );
 472
 473 #define         MoveRecordsRight(src,dst,bytes)                 bcopy((src),(dst),(bytes))
 474
 475
 476 //////////////////////////////// Tree Operations ////////////////////////////////
 477
 478 OSStatus        SearchTree                              (BTreeControlBlockPtr    btreePtr,
 479                                                                          BTreeKeyPtr                     keyPtr,
 480                                                                          TreePathTable                   treePathTable,
 481                                                                          UInt32                                 *nodeNum,
 482                                                                          BlockDescriptor                *nodePtr,
 483                                                                          UInt16                                 *index );
 484
 485 OSStatus        InsertTree                              (BTreeControlBlockPtr    btreePtr,
 486                                                                          TreePathTable                   treePathTable,
 487                                                                          KeyPtr                                  keyPtr,
 488                                                                          UInt8 *                                 recPtr,
 489                                                                          UInt16                                  recSize,
 490                                                                          BlockDescriptor                *targetNode,
 491                                                                          UInt16                                  index,
 492                                                                          UInt16                                  level,
 493                                                                          Boolean                                 replacingKey,
 494                                                                          UInt32                                 *insertNode );
 495
 496 OSStatus        DeleteTree                              (BTreeControlBlockPtr    btreePtr,
 497                                                                          TreePathTable                   treePathTable,
 498                                                                          BlockDescriptor                *targetNode,
 499                                                                          UInt16                                  index,
 500                                                                          UInt16                                  level );
 501
 502 #endif /* __APPLE_API_PRIVATE */
 503 #endif /* KERNEL */
 504 #endif //__BTREESPRIVATE__