2 * Compound Storage (32 bit version)
3 * Stream implementation
5 * This file contains the implementation of the stream interface
6 * for streams contained in a compound storage.
8 * Copyright 1999 Francis Beaudet
9 * Copyright 1999 Thuy Nguyen
20 #include "wine/obj_base.h"
21 #include "wine/obj_storage.h"
23 #include "storage32.h"
27 * Virtual function table for the StgStreamImpl class.
29 static ICOM_VTABLE(IStream32) StgStreamImpl_Vtbl =
31 StgStreamImpl_QueryInterface,
33 StgStreamImpl_Release,
37 StgStreamImpl_SetSize,
41 StgStreamImpl_LockRegion,
42 StgStreamImpl_UnlockRegion,
47 /******************************************************************************
48 ** StgStreamImpl implementation
52 * This is the constructor for the StgStreamImpl class.
55 * parentStorage - Pointer to the storage that contains the stream to open
56 * ownerProperty - Index of the property that points to this stream.
58 StgStreamImpl* StgStreamImpl_Construct(
59 Storage32BaseImpl* parentStorage,
62 StgStreamImpl* newStream;
64 newStream = HeapAlloc(GetProcessHeap(), 0, sizeof(StgStreamImpl));
69 * Set-up the virtual function table and reference count.
71 newStream->lpvtbl = &StgStreamImpl_Vtbl;
75 * We want to nail-down the reference to the storage in case the
76 * stream out-lives the storage in the client application.
78 newStream->parentStorage = parentStorage;
79 IStorage32_AddRef((IStorage32*)newStream->parentStorage);
81 newStream->ownerProperty = ownerProperty;
84 * Start the stream at the begining.
86 newStream->currentPosition.HighPart = 0;
87 newStream->currentPosition.LowPart = 0;
90 * Initialize the rest of the data.
92 newStream->streamSize.HighPart = 0;
93 newStream->streamSize.LowPart = 0;
94 newStream->bigBlockChain = 0;
95 newStream->smallBlockChain = 0;
98 * Read the size from the property and determine if the blocks forming
99 * this stream are large or small.
101 StgStreamImpl_OpenBlockChain(newStream);
108 * This is the destructor of the StgStreamImpl class.
110 * This method will clean-up all the resources used-up by the given StgStreamImpl
111 * class. The pointer passed-in to this function will be freed and will not
114 void StgStreamImpl_Destroy(StgStreamImpl* This)
117 * Release the reference we are holding on the parent storage.
119 IStorage32_Release((IStorage32*)This->parentStorage);
120 This->parentStorage = 0;
123 * Make sure we clean-up the block chain stream objects that we were using.
125 if (This->bigBlockChain != 0)
127 BlockChainStream_Destroy(This->bigBlockChain);
128 This->bigBlockChain = 0;
131 if (This->smallBlockChain != 0)
133 SmallBlockChainStream_Destroy(This->smallBlockChain);
134 This->smallBlockChain = 0;
138 * Finally, free the memory used-up by the class.
140 HeapFree(GetProcessHeap(), 0, This);
144 * This implements the IUnknown method QueryInterface for this
147 HRESULT WINAPI StgStreamImpl_QueryInterface(
149 REFIID riid, /* [in] */
150 void** ppvObject) /* [iid_is][out] */
152 StgStreamImpl* const This=(StgStreamImpl*)iface;
155 * Perform a sanity check on the parameters.
161 * Initialize the return parameter.
166 * Compare the riid with the interface IDs implemented by this object.
168 if (memcmp(&IID_IUnknown, riid, sizeof(IID_IUnknown)) == 0)
170 *ppvObject = (IStream32*)This;
172 else if (memcmp(&IID_IStorage, riid, sizeof(IID_IStream)) == 0)
174 *ppvObject = (IStream32*)This;
178 * Check that we obtained an interface.
181 return E_NOINTERFACE;
184 * Query Interface always increases the reference count by one when it is
187 StgStreamImpl_AddRef(iface);
193 * This implements the IUnknown method AddRef for this
196 ULONG WINAPI StgStreamImpl_AddRef(
199 StgStreamImpl* const This=(StgStreamImpl*)iface;
207 * This implements the IUnknown method Release for this
210 ULONG WINAPI StgStreamImpl_Release(
213 StgStreamImpl* const This=(StgStreamImpl*)iface;
222 * If the reference count goes down to 0, perform suicide.
226 StgStreamImpl_Destroy(This);
233 * This method will open the block chain pointed by the property
234 * that describes the stream.
235 * If the stream's size is null, no chain is opened.
237 void StgStreamImpl_OpenBlockChain(
240 StgProperty curProperty;
241 BOOL32 readSucessful;
244 * Make sure no old object is staying behind.
246 if (This->smallBlockChain != 0)
248 SmallBlockChainStream_Destroy(This->smallBlockChain);
249 This->smallBlockChain = 0;
252 if (This->bigBlockChain != 0)
254 BlockChainStream_Destroy(This->bigBlockChain);
255 This->bigBlockChain = 0;
259 * Read the information from the property.
261 readSucessful = Storage32Impl_ReadProperty(This->parentStorage->ancestorStorage,
267 This->streamSize = curProperty.size;
270 * This code supports only streams that are <32 bits in size.
272 assert(This->streamSize.HighPart == 0);
274 if(curProperty.startingBlock == BLOCK_END_OF_CHAIN)
276 assert( (This->streamSize.HighPart == 0) && (This->streamSize.LowPart == 0) );
280 if ( (This->streamSize.HighPart == 0) &&
281 (This->streamSize.LowPart < LIMIT_TO_USE_SMALL_BLOCK) )
283 This->smallBlockChain = SmallBlockChainStream_Construct(
284 This->parentStorage->ancestorStorage,
285 This->ownerProperty);
289 This->bigBlockChain = BlockChainStream_Construct(
290 This->parentStorage->ancestorStorage,
292 This->ownerProperty);
299 * This method is part of the ISequentialStream interface.
301 * If reads a block of information from the stream at the current
302 * position. It then moves the current position at the end of the
305 * See the documentation of ISequentialStream for more info.
307 HRESULT WINAPI StgStreamImpl_Read(
309 void* pv, /* [length_is][size_is][out] */
311 ULONG* pcbRead) /* [out] */
313 StgStreamImpl* const This=(StgStreamImpl*)iface;
315 ULONG bytesReadBuffer;
316 ULONG bytesToReadFromBuffer;
319 * If the caller is not interested in the nubmer of bytes read,
320 * we use another buffer to avoid "if" statements in the code.
323 pcbRead = &bytesReadBuffer;
326 * Using the known size of the stream, calculate the number of bytes
327 * to read from the block chain
329 bytesToReadFromBuffer = MIN( This->streamSize.LowPart - This->currentPosition.LowPart, cb);
332 * Depending on the type of chain that was opened when the stream was constructed,
333 * we delegate the work to the method that read the block chains.
335 if (This->smallBlockChain!=0)
337 SmallBlockChainStream_ReadAt(This->smallBlockChain,
338 This->currentPosition,
339 bytesToReadFromBuffer,
344 else if (This->bigBlockChain!=0)
346 BlockChainStream_ReadAt(This->bigBlockChain,
347 This->currentPosition,
348 bytesToReadFromBuffer,
356 * We should always be able to read the proper amount of data from the
359 assert(bytesToReadFromBuffer == *pcbRead);
362 * Advance the pointer for the number of positions read.
364 This->currentPosition.LowPart += *pcbRead;
367 * The function returns S_OK if the buffer was filled completely
368 * it returns S_FALSE if the end of the stream is reached before the
378 * This method is part of the ISequentialStream interface.
380 * It writes a block of information to the stream at the current
381 * position. It then moves the current position at the end of the
382 * written block. If the stream is too small to fit the block,
383 * the stream is grown to fit.
385 * See the documentation of ISequentialStream for more info.
387 HRESULT WINAPI StgStreamImpl_Write(
389 const void* pv, /* [size_is][in] */
391 ULONG* pcbWritten) /* [out] */
393 StgStreamImpl* const This=(StgStreamImpl*)iface;
395 ULARGE_INTEGER newSize;
396 ULONG bytesWritten = 0;
399 * If the caller is not interested in the number of bytes written,
400 * we use another buffer to avoid "if" statements in the code.
403 pcbWritten = &bytesWritten;
411 newSize.HighPart = 0;
412 newSize.LowPart = This->currentPosition.LowPart + cb;
416 * Verify if we need to grow the stream
418 if (newSize.LowPart > This->streamSize.LowPart)
421 StgStreamImpl_SetSize(iface, newSize);
425 * Depending on the type of chain that was opened when the stream was constructed,
426 * we delegate the work to the method that readwrites to the block chains.
428 if (This->smallBlockChain!=0)
430 SmallBlockChainStream_WriteAt(This->smallBlockChain,
431 This->currentPosition,
437 else if (This->bigBlockChain!=0)
439 BlockChainStream_WriteAt(This->bigBlockChain,
440 This->currentPosition,
449 * Advance the position pointer for the number of positions written.
451 This->currentPosition.LowPart += *pcbWritten;
457 * This method is part of the IStream interface.
459 * It will move the current stream pointer according to the parameters
462 * See the documentation of IStream for more info.
464 HRESULT WINAPI StgStreamImpl_Seek(
466 LARGE_INTEGER dlibMove, /* [in] */
467 DWORD dwOrigin, /* [in] */
468 ULARGE_INTEGER* plibNewPosition) /* [out] */
470 StgStreamImpl* const This=(StgStreamImpl*)iface;
472 ULARGE_INTEGER newPosition;
475 * The caller is allowed to pass in NULL as the new position return value.
476 * If it happens, we assign it to a dynamic variable to avoid special cases
479 if (plibNewPosition == 0)
481 plibNewPosition = &newPosition;
485 * The file pointer is moved depending on the given "function"
490 case STREAM_SEEK_SET:
491 plibNewPosition->HighPart = 0;
492 plibNewPosition->LowPart = 0;
494 case STREAM_SEEK_CUR:
495 *plibNewPosition = This->currentPosition;
497 case STREAM_SEEK_END:
498 *plibNewPosition = This->streamSize;
501 return STG_E_INVALIDFUNCTION;
505 * We don't support files with offsets of 64 bits.
507 assert(dlibMove.HighPart == 0);
510 * Check if we end-up before the beginning of the file. That should trigger an
513 if ( (dlibMove.LowPart<0) && (plibNewPosition->LowPart < (ULONG)(-dlibMove.LowPart)) )
516 * I don't know what error to send there.
522 * Move the actual file pointer
523 * If the file pointer ends-up after the end of the stream, the next Write operation will
524 * make the file larger. This is how it is documented.
526 plibNewPosition->LowPart += dlibMove.LowPart;
527 This->currentPosition = *plibNewPosition;
533 * This method is part of the IStream interface.
535 * It will change the size of a stream.
537 * TODO: Switch from small blocks to big blocks and vice versa.
539 * See the documentation of IStream for more info.
541 HRESULT WINAPI StgStreamImpl_SetSize(
543 ULARGE_INTEGER libNewSize) /* [in] */
545 StgStreamImpl* const This=(StgStreamImpl*)iface;
547 StgProperty curProperty;
553 if (libNewSize.HighPart != 0)
554 return STG_E_INVALIDFUNCTION;
556 if (This->streamSize.LowPart == libNewSize.LowPart)
560 * This will happen if we're creating a stream
562 if ((This->smallBlockChain == 0) && (This->bigBlockChain == 0))
564 if (libNewSize.LowPart < LIMIT_TO_USE_SMALL_BLOCK)
566 This->smallBlockChain = SmallBlockChainStream_Construct(
567 This->parentStorage->ancestorStorage,
568 This->ownerProperty);
572 This->bigBlockChain = BlockChainStream_Construct(
573 This->parentStorage->ancestorStorage,
575 This->ownerProperty);
580 * Read this stream's property to see if it's small blocks or big blocks
582 Success = Storage32Impl_ReadProperty(This->parentStorage->ancestorStorage,
586 * Determine if we have to switch from small to big blocks or vice versa
589 if (curProperty.size.LowPart < LIMIT_TO_USE_SMALL_BLOCK)
591 if (libNewSize.LowPart >= LIMIT_TO_USE_SMALL_BLOCK)
594 * Transform the small block chain into a big block chain
596 This->bigBlockChain = Storage32Impl_SmallBlocksToBigBlocks(
597 This->parentStorage->ancestorStorage,
598 &This->smallBlockChain);
602 if (This->smallBlockChain!=0)
604 Success = SmallBlockChainStream_SetSize(This->smallBlockChain, libNewSize);
608 Success = BlockChainStream_SetSize(This->bigBlockChain, libNewSize);
612 * Write to the property the new information about this stream
614 Success = Storage32Impl_ReadProperty(This->parentStorage->ancestorStorage,
618 curProperty.size.HighPart = libNewSize.HighPart;
619 curProperty.size.LowPart = libNewSize.LowPart;
623 Storage32Impl_WriteProperty(This->parentStorage->ancestorStorage,
628 This->streamSize = libNewSize;
633 HRESULT WINAPI StgStreamImpl_CopyTo(
635 IStream32* pstm, /* [unique][in] */
636 ULARGE_INTEGER cb, /* [in] */
637 ULARGE_INTEGER* pcbRead, /* [out] */
638 ULARGE_INTEGER* pcbWritten) /* [out] */
644 * This method is part of the IStream interface.
646 * For streams contained in structured storages, this method
647 * does nothing. This is what the documentation tells us.
649 * See the documentation of IStream for more info.
651 HRESULT WINAPI StgStreamImpl_Commit(
653 DWORD grfCommitFlags) /* [in] */
659 * This method is part of the IStream interface.
661 * For streams contained in structured storages, this method
662 * does nothing. This is what the documentation tells us.
664 * See the documentation of IStream for more info.
666 HRESULT WINAPI StgStreamImpl_Revert(
672 HRESULT WINAPI StgStreamImpl_LockRegion(
674 ULARGE_INTEGER libOffset, /* [in] */
675 ULARGE_INTEGER cb, /* [in] */
676 DWORD dwLockType) /* [in] */
681 HRESULT WINAPI StgStreamImpl_UnlockRegion(
683 ULARGE_INTEGER libOffset, /* [in] */
684 ULARGE_INTEGER cb, /* [in] */
685 DWORD dwLockType) /* [in] */
691 * This method is part of the IStream interface.
693 * This method returns information about the current
696 * See the documentation of IStream for more info.
698 HRESULT WINAPI StgStreamImpl_Stat(
700 STATSTG* pstatstg, /* [out] */
701 DWORD grfStatFlag) /* [in] */
703 StgStreamImpl* const This=(StgStreamImpl*)iface;
705 StgProperty curProperty;
706 BOOL32 readSucessful;
709 * Read the information from the property.
711 readSucessful = Storage32Impl_ReadProperty(This->parentStorage->ancestorStorage,
717 StorageUtl_CopyPropertyToSTATSTG(pstatstg,
727 HRESULT WINAPI StgStreamImpl_Clone(
729 IStream32** ppstm) /* [out] */