git.oblomov.eu Git - wine/blob - dlls/ole32/stg_stream.c

   1 /*
   2  * Compound Storage (32 bit version)
   3  * Stream implementation
   4  *
   5  * This file contains the implementation of the stream interface
   6  * for streams contained in a compound storage.
   7  *
   8  * Copyright 1999 Francis Beaudet
   9  * Copyright 1999 Thuy Nguyen
  10  */
  11 #include <assert.h>
  12 #include <stdlib.h>
  13 #include <stdio.h>
  14 #include <string.h>
  15
  16 #include "winbase.h"
  17 #include "winerror.h"
  18 #include "ntddk.h"
  19 #include "debugtools.h"
  20
  21 #include "storage32.h"
  22
  23 DEFAULT_DEBUG_CHANNEL(storage);
  24
  25
  26 /*
  27  * Virtual function table for the StgStreamImpl class.
  28  */
  29 static ICOM_VTABLE(IStream) StgStreamImpl_Vtbl =
  30 {
  31     ICOM_MSVTABLE_COMPAT_DummyRTTIVALUE
  32     StgStreamImpl_QueryInterface,
  33     StgStreamImpl_AddRef,
  34     StgStreamImpl_Release,
  35     StgStreamImpl_Read,
  36     StgStreamImpl_Write,
  37     StgStreamImpl_Seek,
  38     StgStreamImpl_SetSize,
  39     StgStreamImpl_CopyTo,
  40     StgStreamImpl_Commit,
  41     StgStreamImpl_Revert,
  42     StgStreamImpl_LockRegion,
  43     StgStreamImpl_UnlockRegion,
  44     StgStreamImpl_Stat,
  45     StgStreamImpl_Clone
  46 };
  47
  48 /******************************************************************************
  49 ** StgStreamImpl implementation
  50 */
  51
  52 /***
  53  * This is the constructor for the StgStreamImpl class.
  54  *
  55  * Params:
  56  *    parentStorage - Pointer to the storage that contains the stream to open
  57  *    ownerProperty - Index of the property that points to this stream.
  58  */
  59 StgStreamImpl* StgStreamImpl_Construct(
  60                 StorageBaseImpl* parentStorage,
  61     DWORD            grfMode,
  62     ULONG            ownerProperty)
  63 {
  64   StgStreamImpl* newStream;
  65
  66   newStream = HeapAlloc(GetProcessHeap(), 0, sizeof(StgStreamImpl));
  67
  68   if (newStream!=0)
  69   {
  70     /*
  71      * Set-up the virtual function table and reference count.
  72      */
  73     ICOM_VTBL(newStream) = &StgStreamImpl_Vtbl;
  74     newStream->ref       = 0;
  75
  76     /*
  77      * We want to nail-down the reference to the storage in case the
  78      * stream out-lives the storage in the client application.
  79      */
  80     newStream->parentStorage = parentStorage;
  81     IStorage_AddRef((IStorage*)newStream->parentStorage);
  82
  83     newStream->grfMode = grfMode;
  84     newStream->ownerProperty = ownerProperty;
  85
  86     /*
  87      * Start the stream at the begining.
  88      */
  89     newStream->currentPosition.s.HighPart = 0;
  90     newStream->currentPosition.s.LowPart = 0;
  91
  92     /*
  93      * Initialize the rest of the data.
  94      */
  95     newStream->streamSize.s.HighPart = 0;
  96     newStream->streamSize.s.LowPart  = 0;
  97     newStream->bigBlockChain       = 0;
  98     newStream->smallBlockChain     = 0;
  99
 100     /*
 101      * Read the size from the property and determine if the blocks forming
 102      * this stream are large or small.
 103      */
 104     StgStreamImpl_OpenBlockChain(newStream);
 105   }
 106
 107   return newStream;
 108 }
 109
 110 /***
 111  * This is the destructor of the StgStreamImpl class.
 112  *
 113  * This method will clean-up all the resources used-up by the given StgStreamImpl
 114  * class. The pointer passed-in to this function will be freed and will not
 115  * be valid anymore.
 116  */
 117 void StgStreamImpl_Destroy(StgStreamImpl* This)
 118 {
 119   TRACE("(%p)\n", This);
 120
 121   /*
 122    * Release the reference we are holding on the parent storage.
 123    */
 124   IStorage_Release((IStorage*)This->parentStorage);
 125   This->parentStorage = 0;
 126
 127   /*
 128    * Make sure we clean-up the block chain stream objects that we were using.
 129    */
 130   if (This->bigBlockChain != 0)
 131   {
 132     BlockChainStream_Destroy(This->bigBlockChain);
 133     This->bigBlockChain = 0;
 134   }
 135
 136   if (This->smallBlockChain != 0)
 137   {
 138     SmallBlockChainStream_Destroy(This->smallBlockChain);
 139     This->smallBlockChain = 0;
 140   }
 141
 142   /*
 143    * Finally, free the memory used-up by the class.
 144    */
 145   HeapFree(GetProcessHeap(), 0, This);
 146 }
 147
 148 /***
 149  * This implements the IUnknown method QueryInterface for this
 150  * class
 151  */
 152 HRESULT WINAPI StgStreamImpl_QueryInterface(
 153                   IStream*     iface,
 154                   REFIID         riid,        /* [in] */
 155                   void**         ppvObject)   /* [iid_is][out] */
 156 {
 157   StgStreamImpl* const This=(StgStreamImpl*)iface;
 158
 159   /*
 160    * Perform a sanity check on the parameters.
 161    */
 162   if (ppvObject==0)
 163     return E_INVALIDARG;
 164
 165   /*
 166    * Initialize the return parameter.
 167    */
 168   *ppvObject = 0;
 169
 170   /*
 171    * Compare the riid with the interface IDs implemented by this object.
 172    */
 173   if (memcmp(&IID_IUnknown, riid, sizeof(IID_IUnknown)) == 0)
 174   {
 175     *ppvObject = (IStream*)This;
 176   }
 177   else if (memcmp(&IID_IStream, riid, sizeof(IID_IStream)) == 0)
 178   {
 179     *ppvObject = (IStream*)This;
 180   }
 181
 182   /*
 183    * Check that we obtained an interface.
 184    */
 185   if ((*ppvObject)==0)
 186     return E_NOINTERFACE;
 187
 188   /*
 189    * Query Interface always increases the reference count by one when it is
 190    * successful
 191    */
 192   StgStreamImpl_AddRef(iface);
 193
 194   return S_OK;;
 195 }
 196
 197 /***
 198  * This implements the IUnknown method AddRef for this
 199  * class
 200  */
 201 ULONG WINAPI StgStreamImpl_AddRef(
 202                 IStream* iface)
 203 {
 204   StgStreamImpl* const This=(StgStreamImpl*)iface;
 205
 206   This->ref++;
 207
 208   return This->ref;
 209 }
 210
 211 /***
 212  * This implements the IUnknown method Release for this
 213  * class
 214  */
 215 ULONG WINAPI StgStreamImpl_Release(
 216                 IStream* iface)
 217 {
 218   StgStreamImpl* const This=(StgStreamImpl*)iface;
 219
 220   ULONG newRef;
 221
 222   This->ref--;
 223
 224   newRef = This->ref;
 225
 226   /*
 227    * If the reference count goes down to 0, perform suicide.
 228    */
 229   if (newRef==0)
 230   {
 231     StgStreamImpl_Destroy(This);
 232   }
 233
 234   return newRef;
 235 }
 236
 237 /***
 238  * This method will open the block chain pointed by the property
 239  * that describes the stream.
 240  * If the stream's size is null, no chain is opened.
 241  */
 242 void StgStreamImpl_OpenBlockChain(
 243         StgStreamImpl* This)
 244 {
 245   StgProperty    curProperty;
 246   BOOL         readSucessful;
 247
 248   /*
 249    * Make sure no old object is staying behind.
 250    */
 251   if (This->smallBlockChain != 0)
 252   {
 253     SmallBlockChainStream_Destroy(This->smallBlockChain);
 254     This->smallBlockChain = 0;
 255   }
 256
 257   if (This->bigBlockChain != 0)
 258   {
 259     BlockChainStream_Destroy(This->bigBlockChain);
 260     This->bigBlockChain = 0;
 261   }
 262
 263   /*
 264    * Read the information from the property.
 265    */
 266   readSucessful = StorageImpl_ReadProperty(This->parentStorage->ancestorStorage,
 267                                              This->ownerProperty,
 268                                              &curProperty);
 269
 270   if (readSucessful)
 271   {
 272     This->streamSize = curProperty.size;
 273
 274     /*
 275      * This code supports only streams that are <32 bits in size.
 276      */
 277     assert(This->streamSize.s.HighPart == 0);
 278
 279     if(curProperty.startingBlock == BLOCK_END_OF_CHAIN)
 280     {
 281       assert( (This->streamSize.s.HighPart == 0) && (This->streamSize.s.LowPart == 0) );
 282     }
 283     else
 284     {
 285       if ( (This->streamSize.s.HighPart == 0) &&
 286            (This->streamSize.s.LowPart < LIMIT_TO_USE_SMALL_BLOCK) )
 287       {
 288         This->smallBlockChain = SmallBlockChainStream_Construct(
 289                                                                 This->parentStorage->ancestorStorage,
 290                                                                 This->ownerProperty);
 291       }
 292       else
 293       {
 294         This->bigBlockChain = BlockChainStream_Construct(
 295                                                          This->parentStorage->ancestorStorage,
 296                                                          NULL,
 297                                                          This->ownerProperty);
 298       }
 299     }
 300   }
 301 }
 302
 303 /***
 304  * This method is part of the ISequentialStream interface.
 305  *
 306  * If reads a block of information from the stream at the current
 307  * position. It then moves the current position at the end of the
 308  * read block
 309  *
 310  * See the documentation of ISequentialStream for more info.
 311  */
 312 HRESULT WINAPI StgStreamImpl_Read(
 313                   IStream*     iface,
 314                   void*          pv,        /* [length_is][size_is][out] */
 315                   ULONG          cb,        /* [in] */
 316                   ULONG*         pcbRead)   /* [out] */
 317 {
 318   StgStreamImpl* const This=(StgStreamImpl*)iface;
 319
 320   ULONG bytesReadBuffer;
 321   ULONG bytesToReadFromBuffer;
 322
 323   TRACE("(%p, %p, %ld, %p)\n",
 324         iface, pv, cb, pcbRead);
 325
 326   /*
 327    * If the caller is not interested in the nubmer of bytes read,
 328    * we use another buffer to avoid "if" statements in the code.
 329    */
 330   if (pcbRead==0)
 331     pcbRead = &bytesReadBuffer;
 332
 333   /*
 334    * Using the known size of the stream, calculate the number of bytes
 335    * to read from the block chain
 336    */
 337   bytesToReadFromBuffer = min( This->streamSize.s.LowPart - This->currentPosition.s.LowPart, cb);
 338
 339   /*
 340    * Depending on the type of chain that was opened when the stream was constructed,
 341    * we delegate the work to the method that read the block chains.
 342    */
 343   if (This->smallBlockChain!=0)
 344   {
 345     SmallBlockChainStream_ReadAt(This->smallBlockChain,
 346                                  This->currentPosition,
 347                                  bytesToReadFromBuffer,
 348                                  pv,
 349                                  pcbRead);
 350
 351   }
 352   else if (This->bigBlockChain!=0)
 353   {
 354     BlockChainStream_ReadAt(This->bigBlockChain,
 355                             This->currentPosition,
 356                             bytesToReadFromBuffer,
 357                             pv,
 358                             pcbRead);
 359   }
 360   else
 361   {
 362     /*
 363      * Small and big block chains are both NULL. This case will happen
 364      * when a stream starts with BLOCK_END_OF_CHAIN and has size zero.
 365      */
 366
 367     *pcbRead = 0;
 368     return S_OK;
 369   }
 370
 371   /*
 372    * We should always be able to read the proper amount of data from the
 373    * chain.
 374    */
 375   assert(bytesToReadFromBuffer == *pcbRead);
 376
 377   /*
 378    * Advance the pointer for the number of positions read.
 379    */
 380   This->currentPosition.s.LowPart += *pcbRead;
 381
 382   /*
 383    * The function returns S_OK if the buffer was filled completely
 384    * it returns S_FALSE if the end of the stream is reached before the
 385    * buffer is filled
 386    */
 387   if(*pcbRead == cb)
 388     return S_OK;
 389
 390   return S_FALSE;
 391 }
 392
 393 /***
 394  * This method is part of the ISequentialStream interface.
 395  *
 396  * It writes a block of information to the stream at the current
 397  * position. It then moves the current position at the end of the
 398  * written block. If the stream is too small to fit the block,
 399  * the stream is grown to fit.
 400  *
 401  * See the documentation of ISequentialStream for more info.
 402  */
 403 HRESULT WINAPI StgStreamImpl_Write(
 404                   IStream*     iface,
 405                   const void*    pv,          /* [size_is][in] */
 406                   ULONG          cb,          /* [in] */
 407                   ULONG*         pcbWritten)  /* [out] */
 408 {
 409   StgStreamImpl* const This=(StgStreamImpl*)iface;
 410
 411   ULARGE_INTEGER newSize;
 412   ULONG bytesWritten = 0;
 413
 414   TRACE("(%p, %p, %ld, %p)\n",
 415         iface, pv, cb, pcbWritten);
 416
 417   /*
 418    * Do we have permission to write to this stream?
 419    */
 420   if (!(This->grfMode & (STGM_WRITE | STGM_READWRITE))) {
 421       return STG_E_ACCESSDENIED;
 422   }
 423
 424   /*
 425    * If the caller is not interested in the number of bytes written,
 426    * we use another buffer to avoid "if" statements in the code.
 427    */
 428   if (pcbWritten == 0)
 429     pcbWritten = &bytesWritten;
 430
 431   /*
 432    * Initialize the out parameter
 433    */
 434   *pcbWritten = 0;
 435
 436   if (cb == 0)
 437   {
 438     return S_OK;
 439   }
 440   else
 441   {
 442     newSize.s.HighPart = 0;
 443     newSize.s.LowPart = This->currentPosition.s.LowPart + cb;
 444   }
 445
 446   /*
 447    * Verify if we need to grow the stream
 448    */
 449   if (newSize.s.LowPart > This->streamSize.s.LowPart)
 450   {
 451     /* grow stream */
 452     IStream_SetSize(iface, newSize);
 453   }
 454
 455   /*
 456    * Depending on the type of chain that was opened when the stream was constructed,
 457    * we delegate the work to the method that readwrites to the block chains.
 458    */
 459   if (This->smallBlockChain!=0)
 460   {
 461     SmallBlockChainStream_WriteAt(This->smallBlockChain,
 462                                   This->currentPosition,
 463                                   cb,
 464                                   pv,
 465                                   pcbWritten);
 466
 467   }
 468   else if (This->bigBlockChain!=0)
 469   {
 470     BlockChainStream_WriteAt(This->bigBlockChain,
 471                              This->currentPosition,
 472                              cb,
 473                              pv,
 474                              pcbWritten);
 475   }
 476   else
 477     assert(FALSE);
 478
 479   /*
 480    * Advance the position pointer for the number of positions written.
 481    */
 482   This->currentPosition.s.LowPart += *pcbWritten;
 483
 484   return S_OK;
 485 }
 486
 487 /***
 488  * This method is part of the IStream interface.
 489  *
 490  * It will move the current stream pointer according to the parameters
 491  * given.
 492  *
 493  * See the documentation of IStream for more info.
 494  */
 495 HRESULT WINAPI StgStreamImpl_Seek(
 496                   IStream*      iface,
 497                   LARGE_INTEGER   dlibMove,         /* [in] */
 498                   DWORD           dwOrigin,         /* [in] */
 499                   ULARGE_INTEGER* plibNewPosition) /* [out] */
 500 {
 501   StgStreamImpl* const This=(StgStreamImpl*)iface;
 502
 503   ULARGE_INTEGER newPosition;
 504
 505   TRACE("(%p, %ld, %ld, %p)\n",
 506         iface, dlibMove.s.LowPart, dwOrigin, plibNewPosition);
 507
 508   /*
 509    * The caller is allowed to pass in NULL as the new position return value.
 510    * If it happens, we assign it to a dynamic variable to avoid special cases
 511    * in the code below.
 512    */
 513   if (plibNewPosition == 0)
 514   {
 515     plibNewPosition = &newPosition;
 516   }
 517
 518   /*
 519    * The file pointer is moved depending on the given "function"
 520    * parameter.
 521    */
 522   switch (dwOrigin)
 523   {
 524     case STREAM_SEEK_SET:
 525       plibNewPosition->s.HighPart = 0;
 526       plibNewPosition->s.LowPart  = 0;
 527       break;
 528     case STREAM_SEEK_CUR:
 529       *plibNewPosition = This->currentPosition;
 530       break;
 531     case STREAM_SEEK_END:
 532       *plibNewPosition = This->streamSize;
 533       break;
 534     default:
 535       return STG_E_INVALIDFUNCTION;
 536   }
 537
 538   plibNewPosition->QuadPart = RtlLargeIntegerAdd( plibNewPosition->QuadPart, dlibMove.QuadPart );
 539
 540   /*
 541    * tell the caller what we calculated
 542    */
 543   This->currentPosition = *plibNewPosition;
 544
 545   return S_OK;
 546 }
 547
 548 /***
 549  * This method is part of the IStream interface.
 550  *
 551  * It will change the size of a stream.
 552  *
 553  * TODO: Switch from small blocks to big blocks and vice versa.
 554  *
 555  * See the documentation of IStream for more info.
 556  */
 557 HRESULT WINAPI StgStreamImpl_SetSize(
 558                                      IStream*      iface,
 559                                      ULARGE_INTEGER  libNewSize)   /* [in] */
 560 {
 561   StgStreamImpl* const This=(StgStreamImpl*)iface;
 562
 563   StgProperty    curProperty;
 564   BOOL         Success;
 565
 566   TRACE("(%p, %ld)\n", iface, libNewSize.s.LowPart);
 567
 568   /*
 569    * As documented.
 570    */
 571   if (libNewSize.s.HighPart != 0)
 572     return STG_E_INVALIDFUNCTION;
 573
 574   /*
 575    * Do we have permission?
 576    */
 577   if (!(This->grfMode & (STGM_WRITE | STGM_READWRITE)))
 578     return STG_E_ACCESSDENIED;
 579
 580   if (This->streamSize.s.LowPart == libNewSize.s.LowPart)
 581     return S_OK;
 582
 583   /*
 584    * This will happen if we're creating a stream
 585    */
 586   if ((This->smallBlockChain == 0) && (This->bigBlockChain == 0))
 587   {
 588     if (libNewSize.s.LowPart < LIMIT_TO_USE_SMALL_BLOCK)
 589     {
 590       This->smallBlockChain = SmallBlockChainStream_Construct(
 591                                     This->parentStorage->ancestorStorage,
 592                                     This->ownerProperty);
 593     }
 594     else
 595     {
 596       This->bigBlockChain = BlockChainStream_Construct(
 597                                 This->parentStorage->ancestorStorage,
 598                                 NULL,
 599                                 This->ownerProperty);
 600     }
 601   }
 602
 603   /*
 604    * Read this stream's property to see if it's small blocks or big blocks
 605    */
 606   Success = StorageImpl_ReadProperty(This->parentStorage->ancestorStorage,
 607                                        This->ownerProperty,
 608                                        &curProperty);
 609   /*
 610    * Determine if we have to switch from small to big blocks or vice versa
 611    */
 612   if ( (This->smallBlockChain!=0) &&
 613        (curProperty.size.s.LowPart < LIMIT_TO_USE_SMALL_BLOCK) )
 614   {
 615     if (libNewSize.s.LowPart >= LIMIT_TO_USE_SMALL_BLOCK)
 616     {
 617       /*
 618        * Transform the small block chain into a big block chain
 619        */
 620       This->bigBlockChain = Storage32Impl_SmallBlocksToBigBlocks(
 621                                 This->parentStorage->ancestorStorage,
 622                                 &This->smallBlockChain);
 623     }
 624   }
 625
 626   if (This->smallBlockChain!=0)
 627   {
 628     Success = SmallBlockChainStream_SetSize(This->smallBlockChain, libNewSize);
 629   }
 630   else
 631   {
 632     Success = BlockChainStream_SetSize(This->bigBlockChain, libNewSize);
 633   }
 634
 635   /*
 636    * Write to the property the new information about this stream
 637    */
 638   Success = StorageImpl_ReadProperty(This->parentStorage->ancestorStorage,
 639                                        This->ownerProperty,
 640                                        &curProperty);
 641
 642   curProperty.size.s.HighPart = libNewSize.s.HighPart;
 643   curProperty.size.s.LowPart = libNewSize.s.LowPart;
 644
 645   if (Success)
 646   {
 647     StorageImpl_WriteProperty(This->parentStorage->ancestorStorage,
 648                                 This->ownerProperty,
 649                                 &curProperty);
 650   }
 651
 652   This->streamSize = libNewSize;
 653
 654   return S_OK;
 655 }
 656
 657 /***
 658  * This method is part of the IStream interface.
 659  *
 660  * It will copy the 'cb' Bytes to 'pstm' IStream.
 661  *
 662  * See the documentation of IStream for more info.
 663  */
 664 HRESULT WINAPI StgStreamImpl_CopyTo(
 665                                     IStream*      iface,
 666                                     IStream*      pstm,         /* [unique][in] */
 667                                     ULARGE_INTEGER  cb,           /* [in] */
 668                                     ULARGE_INTEGER* pcbRead,      /* [out] */
 669                                     ULARGE_INTEGER* pcbWritten)   /* [out] */
 670 {
 671   HRESULT        hr = S_OK;
 672   BYTE           tmpBuffer[128];
 673   ULONG          bytesRead, bytesWritten, copySize;
 674   ULARGE_INTEGER totalBytesRead;
 675   ULARGE_INTEGER totalBytesWritten;
 676
 677   TRACE("(%p, %p, %ld, %p, %p)\n",
 678         iface, pstm, cb.s.LowPart, pcbRead, pcbWritten);
 679
 680   /*
 681    * Sanity check
 682    */
 683   if ( pstm == 0 )
 684     return STG_E_INVALIDPOINTER;
 685
 686   totalBytesRead.s.LowPart = totalBytesRead.s.HighPart = 0;
 687   totalBytesWritten.s.LowPart = totalBytesWritten.s.HighPart = 0;
 688
 689   /*
 690    * use stack to store data temporarly
 691    * there is surely more performant way of doing it, for now this basic
 692    * implementation will do the job
 693    */
 694   while ( cb.s.LowPart > 0 )
 695   {
 696     if ( cb.s.LowPart >= 128 )
 697       copySize = 128;
 698     else
 699       copySize = cb.s.LowPart;
 700
 701     IStream_Read(iface, tmpBuffer, copySize, &bytesRead);
 702
 703     totalBytesRead.s.LowPart += bytesRead;
 704
 705     IStream_Write(pstm, tmpBuffer, bytesRead, &bytesWritten);
 706
 707     totalBytesWritten.s.LowPart += bytesWritten;
 708
 709     /*
 710      * Check that read & write operations were succesfull
 711      */
 712     if (bytesRead != bytesWritten)
 713     {
 714       hr = STG_E_MEDIUMFULL;
 715       break;
 716     }
 717
 718     if (bytesRead!=copySize)
 719       cb.s.LowPart = 0;
 720     else
 721       cb.s.LowPart -= bytesRead;
 722   }
 723
 724   /*
 725    * Update number of bytes read and written
 726    */
 727   if (pcbRead)
 728   {
 729     pcbRead->s.LowPart = totalBytesRead.s.LowPart;
 730     pcbRead->s.HighPart = totalBytesRead.s.HighPart;
 731   }
 732
 733   if (pcbWritten)
 734   {
 735     pcbWritten->s.LowPart = totalBytesWritten.s.LowPart;
 736     pcbWritten->s.HighPart = totalBytesWritten.s.HighPart;
 737   }
 738   return hr;
 739 }
 740
 741 /***
 742  * This method is part of the IStream interface.
 743  *
 744  * For streams contained in structured storages, this method
 745  * does nothing. This is what the documentation tells us.
 746  *
 747  * See the documentation of IStream for more info.
 748  */
 749 HRESULT WINAPI StgStreamImpl_Commit(
 750                   IStream*      iface,
 751                   DWORD           grfCommitFlags)  /* [in] */
 752 {
 753   return S_OK;
 754 }
 755
 756 /***
 757  * This method is part of the IStream interface.
 758  *
 759  * For streams contained in structured storages, this method
 760  * does nothing. This is what the documentation tells us.
 761  *
 762  * See the documentation of IStream for more info.
 763  */
 764 HRESULT WINAPI StgStreamImpl_Revert(
 765                   IStream* iface)
 766 {
 767   return S_OK;
 768 }
 769
 770 HRESULT WINAPI StgStreamImpl_LockRegion(
 771                                         IStream*     iface,
 772                                         ULARGE_INTEGER libOffset,   /* [in] */
 773                                         ULARGE_INTEGER cb,          /* [in] */
 774                                         DWORD          dwLockType)  /* [in] */
 775 {
 776   FIXME("not implemented!\n");
 777   return E_NOTIMPL;
 778 }
 779
 780 HRESULT WINAPI StgStreamImpl_UnlockRegion(
 781                                           IStream*     iface,
 782                                           ULARGE_INTEGER libOffset,   /* [in] */
 783                                           ULARGE_INTEGER cb,          /* [in] */
 784                                           DWORD          dwLockType)  /* [in] */
 785 {
 786   FIXME("not implemented!\n");
 787   return E_NOTIMPL;
 788 }
 789
 790 /***
 791  * This method is part of the IStream interface.
 792  *
 793  * This method returns information about the current
 794  * stream.
 795  *
 796  * See the documentation of IStream for more info.
 797  */
 798 HRESULT WINAPI StgStreamImpl_Stat(
 799                   IStream*     iface,
 800                   STATSTG*       pstatstg,     /* [out] */
 801                   DWORD          grfStatFlag)  /* [in] */
 802 {
 803   StgStreamImpl* const This=(StgStreamImpl*)iface;
 804
 805   StgProperty    curProperty;
 806   BOOL         readSucessful;
 807
 808   /*
 809    * Read the information from the property.
 810    */
 811   readSucessful = StorageImpl_ReadProperty(This->parentStorage->ancestorStorage,
 812                                              This->ownerProperty,
 813                                              &curProperty);
 814
 815   if (readSucessful)
 816   {
 817     StorageUtl_CopyPropertyToSTATSTG(pstatstg,
 818                                      &curProperty,
 819                                      grfStatFlag);
 820
 821     pstatstg->grfMode = This->grfMode;
 822
 823     return S_OK;
 824   }
 825
 826   return E_FAIL;
 827 }
 828
 829 HRESULT WINAPI StgStreamImpl_Clone(
 830                                    IStream*     iface,
 831                                    IStream**    ppstm) /* [out] */
 832 {
 833   FIXME("not implemented!\n");
 834   return E_NOTIMPL;
 835 }