dlls/ole32/storage32.h

   1 /*
   2  * Compound Storage (32 bit version)
   3  *
   4  * Implemented using the documentation of the LAOLA project at
   5  * <URL:http://wwwwbs.cs.tu-berlin.de/~schwartz/pmh/index.html>
   6  * (Thanks to Martin Schwartz <schwartz@cs.tu-berlin.de>)
   7  *
   8  * This include file contains definitions of types and function
   9  * prototypes that are used in the many files implementing the
  10  * storage functionality
  11  *
  12  * Copyright 1998,1999 Francis Beaudet
  13  * Copyright 1998,1999 Thuy Nguyen
  14  * Copyright 2010 Vincent Povirk for CodeWeavers
  15  *
  16  * This library is free software; you can redistribute it and/or
  17  * modify it under the terms of the GNU Lesser General Public
  18  * License as published by the Free Software Foundation; either
  19  * version 2.1 of the License, or (at your option) any later version.
  20  *
  21  * This library is distributed in the hope that it will be useful,
  22  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  23  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  24  * Lesser General Public License for more details.
  25  *
  26  * You should have received a copy of the GNU Lesser General Public
  27  * License along with this library; if not, write to the Free Software
  28  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  29  */
  30 #ifndef __STORAGE32_H__
  31 #define __STORAGE32_H__
  32
  33 #include <stdarg.h>
  34
  35 #include "windef.h"
  36 #include "winbase.h"
  37 #include "winnt.h"
  38 #include "objbase.h"
  39 #include "winreg.h"
  40 #include "winternl.h"
  41 #include "wine/list.h"
  42
  43 /*
  44  * Definitions for the file format offsets.
  45  */
  46 static const ULONG OFFSET_MINORVERSION       = 0x00000018;
  47 static const ULONG OFFSET_MAJORVERSION       = 0x0000001a;
  48 static const ULONG OFFSET_BYTEORDERMARKER    = 0x0000001c;
  49 static const ULONG OFFSET_BIGBLOCKSIZEBITS   = 0x0000001e;
  50 static const ULONG OFFSET_SMALLBLOCKSIZEBITS = 0x00000020;
  51 static const ULONG OFFSET_DIRSECTORCOUNT     = 0x00000028;
  52 static const ULONG OFFSET_BBDEPOTCOUNT       = 0x0000002C;
  53 static const ULONG OFFSET_ROOTSTARTBLOCK     = 0x00000030;
  54 static const ULONG OFFSET_SMALLBLOCKLIMIT    = 0x00000038;
  55 static const ULONG OFFSET_SBDEPOTSTART       = 0x0000003C;
  56 static const ULONG OFFSET_SBDEPOTCOUNT       = 0x00000040;
  57 static const ULONG OFFSET_EXTBBDEPOTSTART    = 0x00000044;
  58 static const ULONG OFFSET_EXTBBDEPOTCOUNT    = 0x00000048;
  59 static const ULONG OFFSET_BBDEPOTSTART       = 0x0000004C;
  60 static const ULONG OFFSET_PS_NAME            = 0x00000000;
  61 static const ULONG OFFSET_PS_NAMELENGTH      = 0x00000040;
  62 static const ULONG OFFSET_PS_STGTYPE         = 0x00000042;
  63 static const ULONG OFFSET_PS_LEFTCHILD       = 0x00000044;
  64 static const ULONG OFFSET_PS_RIGHTCHILD      = 0x00000048;
  65 static const ULONG OFFSET_PS_DIRROOT         = 0x0000004C;
  66 static const ULONG OFFSET_PS_GUID            = 0x00000050;
  67 static const ULONG OFFSET_PS_CTIMELOW        = 0x00000064;
  68 static const ULONG OFFSET_PS_CTIMEHIGH       = 0x00000068;
  69 static const ULONG OFFSET_PS_MTIMELOW        = 0x0000006C;
  70 static const ULONG OFFSET_PS_MTIMEHIGH       = 0x00000070;
  71 static const ULONG OFFSET_PS_STARTBLOCK      = 0x00000074;
  72 static const ULONG OFFSET_PS_SIZE            = 0x00000078;
  73 static const WORD  DEF_BIG_BLOCK_SIZE_BITS   = 0x0009;
  74 static const WORD  MIN_BIG_BLOCK_SIZE_BITS   = 0x0009;
  75 static const WORD  MAX_BIG_BLOCK_SIZE_BITS   = 0x000c;
  76 static const WORD  DEF_SMALL_BLOCK_SIZE_BITS = 0x0006;
  77 static const WORD  DEF_BIG_BLOCK_SIZE        = 0x0200;
  78 static const WORD  DEF_SMALL_BLOCK_SIZE      = 0x0040;
  79 static const ULONG BLOCK_EXTBBDEPOT          = 0xFFFFFFFC;
  80 static const ULONG BLOCK_SPECIAL             = 0xFFFFFFFD;
  81 static const ULONG BLOCK_END_OF_CHAIN        = 0xFFFFFFFE;
  82 static const ULONG BLOCK_UNUSED              = 0xFFFFFFFF;
  83 static const ULONG DIRENTRY_NULL             = 0xFFFFFFFF;
  84
  85 #define DIRENTRY_NAME_MAX_LEN    0x20
  86 #define DIRENTRY_NAME_BUFFER_LEN 0x40
  87
  88 #define RAW_DIRENTRY_SIZE 0x00000080
  89
  90 #define HEADER_SIZE 512
  91
  92 #define MIN_BIG_BLOCK_SIZE 0x200
  93 #define MAX_BIG_BLOCK_SIZE 0x1000
  94
  95 /*
  96  * Type of child entry link
  97  */
  98 #define DIRENTRY_RELATION_PREVIOUS 0
  99 #define DIRENTRY_RELATION_NEXT     1
 100 #define DIRENTRY_RELATION_DIR      2
 101
 102 /*
 103  * type constant used in files for the root storage
 104  */
 105 #define STGTY_ROOT 0x05
 106
 107 #define COUNT_BBDEPOTINHEADER    109
 108
 109 /* FIXME: This value is stored in the header, but we hard-code it to 0x1000. */
 110 #define LIMIT_TO_USE_SMALL_BLOCK 0x1000
 111
 112 #define STGM_ACCESS_MODE(stgm)   ((stgm)&0x0000f)
 113 #define STGM_SHARE_MODE(stgm)    ((stgm)&0x000f0)
 114 #define STGM_CREATE_MODE(stgm)   ((stgm)&0x0f000)
 115
 116 #define STGM_KNOWN_FLAGS (0xf0ff | \
 117      STGM_TRANSACTED | STGM_CONVERT | STGM_PRIORITY | STGM_NOSCRATCH | \
 118      STGM_NOSNAPSHOT | STGM_DIRECT_SWMR | STGM_DELETEONRELEASE | STGM_SIMPLE)
 119
 120 /*
 121  * Forward declarations of all the structures used by the storage
 122  * module.
 123  */
 124 typedef struct StorageBaseImpl     StorageBaseImpl;
 125 typedef struct StorageBaseImplVtbl StorageBaseImplVtbl;
 126 typedef struct StorageImpl         StorageImpl;
 127 typedef struct BlockChainStream      BlockChainStream;
 128 typedef struct SmallBlockChainStream SmallBlockChainStream;
 129 typedef struct IEnumSTATSTGImpl      IEnumSTATSTGImpl;
 130 typedef struct DirEntry              DirEntry;
 131 typedef struct StgStreamImpl         StgStreamImpl;
 132
 133 /*
 134  * A reference to a directory entry in the file or a transacted cache.
 135  */
 136 typedef ULONG DirRef;
 137
 138 /*
 139  * This utility structure is used to read/write the information in a directory
 140  * entry.
 141  */
 142 struct DirEntry
 143 {
 144   WCHAR          name[DIRENTRY_NAME_MAX_LEN];
 145   WORD           sizeOfNameString;
 146   BYTE           stgType;
 147   DirRef         leftChild;
 148   DirRef         rightChild;
 149   DirRef         dirRootEntry;
 150   GUID           clsid;
 151   FILETIME       ctime;
 152   FILETIME       mtime;
 153   ULONG          startingBlock;
 154   ULARGE_INTEGER size;
 155 };
 156
 157 HRESULT FileLockBytesImpl_Construct(HANDLE hFile, DWORD openFlags, LPCWSTR pwcsName, ILockBytes **pLockBytes) DECLSPEC_HIDDEN;
 158
 159 /*************************************************************************
 160  * Ole Convert support
 161  */
 162
 163 HRESULT STORAGE_CreateOleStream(IStorage*, DWORD) DECLSPEC_HIDDEN;
 164 HRESULT OLECONVERT_CreateCompObjStream(LPSTORAGE pStorage, LPCSTR strOleTypeName) DECLSPEC_HIDDEN;
 165
 166
 167 /****************************************************************************
 168  * StorageBaseImpl definitions.
 169  *
 170  * This structure defines the base information contained in all implementations
 171  * of IStorage contained in this file storage implementation.
 172  *
 173  * In OOP terms, this is the base class for all the IStorage implementations
 174  * contained in this file.
 175  */
 176 struct StorageBaseImpl
 177 {
 178   IStorage IStorage_iface;
 179   IPropertySetStorage IPropertySetStorage_iface; /* interface for adding a properties stream */
 180   LONG ref;
 181
 182   /*
 183    * Stream tracking list
 184    */
 185
 186   struct list strmHead;
 187
 188   /*
 189    * Storage tracking list
 190    */
 191   struct list storageHead;
 192
 193   /*
 194    * TRUE if this object has been invalidated
 195    */
 196   int reverted;
 197
 198   /*
 199    * Index of the directory entry of this storage
 200    */
 201   DirRef storageDirEntry;
 202
 203   /*
 204    * virtual methods.
 205    */
 206   const StorageBaseImplVtbl *baseVtbl;
 207
 208   /*
 209    * flags that this storage was opened or created with
 210    */
 211   DWORD openFlags;
 212
 213   /*
 214    * State bits appear to only be preserved while running. No in the stream
 215    */
 216   DWORD stateBits;
 217
 218   BOOL             create;     /* Was the storage created or opened.
 219                                   The behaviour of STGM_SIMPLE depends on this */
 220   /*
 221    * If this storage was opened in transacted mode, the object that implements
 222    * the transacted snapshot or cache.
 223    */
 224   StorageBaseImpl *transactedChild;
 225 };
 226
 227 /* virtual methods for StorageBaseImpl objects */
 228 struct StorageBaseImplVtbl {
 229   void (*Destroy)(StorageBaseImpl*);
 230   void (*Invalidate)(StorageBaseImpl*);
 231   HRESULT (*Flush)(StorageBaseImpl*);
 232   HRESULT (*GetFilename)(StorageBaseImpl*,LPWSTR*);
 233   HRESULT (*CreateDirEntry)(StorageBaseImpl*,const DirEntry*,DirRef*);
 234   HRESULT (*WriteDirEntry)(StorageBaseImpl*,DirRef,const DirEntry*);
 235   HRESULT (*ReadDirEntry)(StorageBaseImpl*,DirRef,DirEntry*);
 236   HRESULT (*DestroyDirEntry)(StorageBaseImpl*,DirRef);
 237   HRESULT (*StreamReadAt)(StorageBaseImpl*,DirRef,ULARGE_INTEGER,ULONG,void*,ULONG*);
 238   HRESULT (*StreamWriteAt)(StorageBaseImpl*,DirRef,ULARGE_INTEGER,ULONG,const void*,ULONG*);
 239   HRESULT (*StreamSetSize)(StorageBaseImpl*,DirRef,ULARGE_INTEGER);
 240   HRESULT (*StreamLink)(StorageBaseImpl*,DirRef,DirRef);
 241 };
 242
 243 static inline void StorageBaseImpl_Destroy(StorageBaseImpl *This)
 244 {
 245   This->baseVtbl->Destroy(This);
 246 }
 247
 248 static inline void StorageBaseImpl_Invalidate(StorageBaseImpl *This)
 249 {
 250   This->baseVtbl->Invalidate(This);
 251 }
 252
 253 static inline HRESULT StorageBaseImpl_Flush(StorageBaseImpl *This)
 254 {
 255   return This->baseVtbl->Flush(This);
 256 }
 257
 258 static inline HRESULT StorageBaseImpl_GetFilename(StorageBaseImpl *This, LPWSTR *result)
 259 {
 260   return This->baseVtbl->GetFilename(This, result);
 261 }
 262
 263 static inline HRESULT StorageBaseImpl_CreateDirEntry(StorageBaseImpl *This,
 264   const DirEntry *newData, DirRef *index)
 265 {
 266   return This->baseVtbl->CreateDirEntry(This, newData, index);
 267 }
 268
 269 static inline HRESULT StorageBaseImpl_WriteDirEntry(StorageBaseImpl *This,
 270   DirRef index, const DirEntry *data)
 271 {
 272   return This->baseVtbl->WriteDirEntry(This, index, data);
 273 }
 274
 275 static inline HRESULT StorageBaseImpl_ReadDirEntry(StorageBaseImpl *This,
 276   DirRef index, DirEntry *data)
 277 {
 278   return This->baseVtbl->ReadDirEntry(This, index, data);
 279 }
 280
 281 static inline HRESULT StorageBaseImpl_DestroyDirEntry(StorageBaseImpl *This,
 282   DirRef index)
 283 {
 284   return This->baseVtbl->DestroyDirEntry(This, index);
 285 }
 286
 287 /* Read up to size bytes from this directory entry's stream at the given offset. */
 288 static inline HRESULT StorageBaseImpl_StreamReadAt(StorageBaseImpl *This,
 289   DirRef index, ULARGE_INTEGER offset, ULONG size, void *buffer, ULONG *bytesRead)
 290 {
 291   return This->baseVtbl->StreamReadAt(This, index, offset, size, buffer, bytesRead);
 292 }
 293
 294 /* Write size bytes to this directory entry's stream at the given offset,
 295  * growing the stream if necessary. */
 296 static inline HRESULT StorageBaseImpl_StreamWriteAt(StorageBaseImpl *This,
 297   DirRef index, ULARGE_INTEGER offset, ULONG size, const void *buffer, ULONG *bytesWritten)
 298 {
 299   return This->baseVtbl->StreamWriteAt(This, index, offset, size, buffer, bytesWritten);
 300 }
 301
 302 static inline HRESULT StorageBaseImpl_StreamSetSize(StorageBaseImpl *This,
 303   DirRef index, ULARGE_INTEGER newsize)
 304 {
 305   return This->baseVtbl->StreamSetSize(This, index, newsize);
 306 }
 307
 308 /* Make dst point to the same stream that src points to. Other stream operations
 309  * will not work properly for entries that point to the same stream, so this
 310  * must be a very temporary state, and only one entry pointing to a given stream
 311  * may be reachable at any given time. */
 312 static inline HRESULT StorageBaseImpl_StreamLink(StorageBaseImpl *This,
 313   DirRef dst, DirRef src)
 314 {
 315   return This->baseVtbl->StreamLink(This, dst, src);
 316 }
 317
 318 /****************************************************************************
 319  * StorageBaseImpl stream list handlers
 320  */
 321
 322 void StorageBaseImpl_AddStream(StorageBaseImpl * stg, StgStreamImpl * strm) DECLSPEC_HIDDEN;
 323 void StorageBaseImpl_RemoveStream(StorageBaseImpl * stg, StgStreamImpl * strm) DECLSPEC_HIDDEN;
 324
 325 /* Number of BlockChainStream objects to cache in a StorageImpl */
 326 #define BLOCKCHAIN_CACHE_SIZE 4
 327
 328 /****************************************************************************
 329  * Storage32Impl definitions.
 330  *
 331  * This implementation of the IStorage32 interface represents a root
 332  * storage. Basically, a document file.
 333  */
 334 struct StorageImpl
 335 {
 336   struct StorageBaseImpl base;
 337
 338   /*
 339    * File header
 340    */
 341   WORD  bigBlockSizeBits;
 342   WORD  smallBlockSizeBits;
 343   ULONG bigBlockSize;
 344   ULONG smallBlockSize;
 345   ULONG bigBlockDepotCount;
 346   ULONG rootStartBlock;
 347   ULONG smallBlockLimit;
 348   ULONG smallBlockDepotStart;
 349   ULONG extBigBlockDepotStart;
 350   ULONG *extBigBlockDepotLocations;
 351   ULONG extBigBlockDepotLocationsSize;
 352   ULONG extBigBlockDepotCount;
 353   ULONG bigBlockDepotStart[COUNT_BBDEPOTINHEADER];
 354
 355   ULONG extBlockDepotCached[MAX_BIG_BLOCK_SIZE / 4];
 356   ULONG indexExtBlockDepotCached;
 357
 358   ULONG blockDepotCached[MAX_BIG_BLOCK_SIZE / 4];
 359   ULONG indexBlockDepotCached;
 360   ULONG prevFreeBlock;
 361
 362   /* All small blocks before this one are known to be in use. */
 363   ULONG firstFreeSmallBlock;
 364
 365   /*
 366    * Abstraction of the big block chains for the chains of the header.
 367    */
 368   BlockChainStream* rootBlockChain;
 369   BlockChainStream* smallBlockDepotChain;
 370   BlockChainStream* smallBlockRootChain;
 371
 372   /* Cache of block chain streams objects for directory entries */
 373   BlockChainStream* blockChainCache[BLOCKCHAIN_CACHE_SIZE];
 374   UINT blockChainToEvict;
 375
 376   ILockBytes* lockBytes;
 377 };
 378
 379 HRESULT StorageImpl_ReadRawDirEntry(
 380             StorageImpl *This,
 381             ULONG index,
 382             BYTE *buffer) DECLSPEC_HIDDEN;
 383
 384 void UpdateRawDirEntry(
 385     BYTE *buffer,
 386     const DirEntry *newData) DECLSPEC_HIDDEN;
 387
 388 HRESULT StorageImpl_WriteRawDirEntry(
 389             StorageImpl *This,
 390             ULONG index,
 391             const BYTE *buffer) DECLSPEC_HIDDEN;
 392
 393 HRESULT StorageImpl_ReadDirEntry(
 394             StorageImpl*    This,
 395             DirRef          index,
 396             DirEntry*       buffer) DECLSPEC_HIDDEN;
 397
 398 HRESULT StorageImpl_WriteDirEntry(
 399             StorageImpl*        This,
 400             DirRef              index,
 401             const DirEntry*     buffer) DECLSPEC_HIDDEN;
 402
 403 BlockChainStream* Storage32Impl_SmallBlocksToBigBlocks(
 404                       StorageImpl* This,
 405                       SmallBlockChainStream** ppsbChain) DECLSPEC_HIDDEN;
 406
 407 SmallBlockChainStream* Storage32Impl_BigBlocksToSmallBlocks(
 408                       StorageImpl* This,
 409                       BlockChainStream** ppbbChain,
 410                       ULARGE_INTEGER newSize) DECLSPEC_HIDDEN;
 411
 412 /****************************************************************************
 413  * StgStreamImpl definitions.
 414  *
 415  * This class implements the IStream interface and represents a stream
 416  * located inside a storage object.
 417  */
 418 struct StgStreamImpl
 419 {
 420   IStream IStream_iface;
 421   LONG ref;
 422
 423   /*
 424    * We are an entry in the storage object's stream handler list
 425    */
 426   struct list StrmListEntry;
 427
 428   /*
 429    * Storage that is the parent(owner) of the stream
 430    */
 431   StorageBaseImpl* parentStorage;
 432
 433   /*
 434    * Access mode of this stream.
 435    */
 436   DWORD grfMode;
 437
 438   /*
 439    * Index of the directory entry that owns (points to) this stream.
 440    */
 441   DirRef             dirEntry;
 442
 443   /*
 444    * This is the current position of the cursor in the stream
 445    */
 446   ULARGE_INTEGER     currentPosition;
 447 };
 448
 449 static inline StgStreamImpl *impl_from_IStream( IStream *iface )
 450 {
 451     return CONTAINING_RECORD(iface, StgStreamImpl, IStream_iface);
 452 }
 453
 454 /*
 455  * Method definition for the StgStreamImpl class.
 456  */
 457 StgStreamImpl* StgStreamImpl_Construct(
 458                 StorageBaseImpl* parentStorage,
 459     DWORD            grfMode,
 460     DirRef           dirEntry) DECLSPEC_HIDDEN;
 461
 462
 463 /******************************************************************************
 464  * Endian conversion macros
 465  */
 466 #ifdef WORDS_BIGENDIAN
 467
 468 #define htole32(x) RtlUlongByteSwap(x)
 469 #define htole16(x) RtlUshortByteSwap(x)
 470 #define lendian32toh(x) RtlUlongByteSwap(x)
 471 #define lendian16toh(x) RtlUshortByteSwap(x)
 472
 473 #else
 474
 475 #define htole32(x) (x)
 476 #define htole16(x) (x)
 477 #define lendian32toh(x) (x)
 478 #define lendian16toh(x) (x)
 479
 480 #endif
 481
 482 /******************************************************************************
 483  * The StorageUtl_ functions are miscellaneous utility functions. Most of which
 484  * are abstractions used to read values from file buffers without having to
 485  * worry about bit order
 486  */
 487 void StorageUtl_ReadWord(const BYTE* buffer, ULONG offset, WORD* value) DECLSPEC_HIDDEN;
 488 void StorageUtl_WriteWord(BYTE* buffer, ULONG offset, WORD value) DECLSPEC_HIDDEN;
 489 void StorageUtl_ReadDWord(const BYTE* buffer, ULONG offset, DWORD* value) DECLSPEC_HIDDEN;
 490 void StorageUtl_WriteDWord(BYTE* buffer, ULONG offset, DWORD value) DECLSPEC_HIDDEN;
 491 void StorageUtl_ReadULargeInteger(const BYTE* buffer, ULONG offset,
 492  ULARGE_INTEGER* value) DECLSPEC_HIDDEN;
 493 void StorageUtl_WriteULargeInteger(BYTE* buffer, ULONG offset,
 494  const ULARGE_INTEGER *value) DECLSPEC_HIDDEN;
 495 void StorageUtl_ReadGUID(const BYTE* buffer, ULONG offset, GUID* value) DECLSPEC_HIDDEN;
 496 void StorageUtl_WriteGUID(BYTE* buffer, ULONG offset, const GUID* value) DECLSPEC_HIDDEN;
 497 void StorageUtl_CopyDirEntryToSTATSTG(StorageBaseImpl *storage,STATSTG* destination,
 498  const DirEntry* source, int statFlags) DECLSPEC_HIDDEN;
 499
 500 /****************************************************************************
 501  * BlockChainStream definitions.
 502  *
 503  * The BlockChainStream class is a utility class that is used to create an
 504  * abstraction of the big block chains in the storage file.
 505  */
 506 struct BlockChainRun
 507 {
 508   /* This represents a range of blocks that happen reside in consecutive sectors. */
 509   ULONG firstSector;
 510   ULONG firstOffset;
 511   ULONG lastOffset;
 512 };
 513
 514 typedef struct BlockChainBlock
 515 {
 516   ULONG index;
 517   ULONG sector;
 518   int read;
 519   int dirty;
 520   BYTE data[MAX_BIG_BLOCK_SIZE];
 521 } BlockChainBlock;
 522
 523 struct BlockChainStream
 524 {
 525   StorageImpl* parentStorage;
 526   ULONG*       headOfStreamPlaceHolder;
 527   DirRef       ownerDirEntry;
 528   struct BlockChainRun* indexCache;
 529   ULONG        indexCacheLen;
 530   ULONG        indexCacheSize;
 531   BlockChainBlock cachedBlocks[2];
 532   ULONG        blockToEvict;
 533   ULONG        tailIndex;
 534   ULONG        numBlocks;
 535 };
 536
 537 /*
 538  * Methods for the BlockChainStream class.
 539  */
 540 BlockChainStream* BlockChainStream_Construct(
 541                 StorageImpl* parentStorage,
 542                 ULONG*         headOfStreamPlaceHolder,
 543                 DirRef         dirEntry) DECLSPEC_HIDDEN;
 544
 545 void BlockChainStream_Destroy(
 546                 BlockChainStream* This) DECLSPEC_HIDDEN;
 547
 548 HRESULT BlockChainStream_ReadAt(
 549                 BlockChainStream* This,
 550                 ULARGE_INTEGER offset,
 551                 ULONG          size,
 552                 void*          buffer,
 553                 ULONG*         bytesRead) DECLSPEC_HIDDEN;
 554
 555 HRESULT BlockChainStream_WriteAt(
 556                 BlockChainStream* This,
 557                 ULARGE_INTEGER offset,
 558                 ULONG          size,
 559                 const void*    buffer,
 560                 ULONG*         bytesWritten) DECLSPEC_HIDDEN;
 561
 562 BOOL BlockChainStream_SetSize(
 563                 BlockChainStream* This,
 564                 ULARGE_INTEGER    newSize) DECLSPEC_HIDDEN;
 565
 566 HRESULT BlockChainStream_Flush(
 567                 BlockChainStream* This) DECLSPEC_HIDDEN;
 568
 569 /****************************************************************************
 570  * SmallBlockChainStream definitions.
 571  *
 572  * The SmallBlockChainStream class is a utility class that is used to create an
 573  * abstraction of the small block chains in the storage file.
 574  */
 575 struct SmallBlockChainStream
 576 {
 577   StorageImpl* parentStorage;
 578   DirRef         ownerDirEntry;
 579   ULONG*         headOfStreamPlaceHolder;
 580 };
 581
 582 /*
 583  * Methods of the SmallBlockChainStream class.
 584  */
 585 SmallBlockChainStream* SmallBlockChainStream_Construct(
 586            StorageImpl*   parentStorage,
 587            ULONG*         headOfStreamPlaceHolder,
 588            DirRef         dirEntry) DECLSPEC_HIDDEN;
 589
 590 void SmallBlockChainStream_Destroy(
 591                SmallBlockChainStream* This) DECLSPEC_HIDDEN;
 592
 593 HRESULT SmallBlockChainStream_ReadAt(
 594                SmallBlockChainStream* This,
 595                ULARGE_INTEGER offset,
 596                ULONG          size,
 597                void*          buffer,
 598                ULONG*         bytesRead) DECLSPEC_HIDDEN;
 599
 600 HRESULT SmallBlockChainStream_WriteAt(
 601                SmallBlockChainStream* This,
 602                ULARGE_INTEGER offset,
 603                ULONG          size,
 604                const void*    buffer,
 605                ULONG*         bytesWritten) DECLSPEC_HIDDEN;
 606
 607 BOOL SmallBlockChainStream_SetSize(
 608                SmallBlockChainStream* This,
 609                ULARGE_INTEGER          newSize) DECLSPEC_HIDDEN;
 610
 611
 612 #endif /* __STORAGE32_H__ */