/* * Compound Storage (32 bit version) * Stream implementation * * This file contains the implementation of the stream interface * for streams contained in a compound storage. * * Copyright 1999 Francis Beaudet * Copyright 1999 Thuy Nguyen */ #include #include #include #include #include "windows.h" #include "winerror.h" #include "ole.h" #include "ole2.h" #include "wine/obj_base.h" #include "wine/obj_storage.h" #include "storage32.h" /* * Virtual function table for the StgStreamImpl class. */ static ICOM_VTABLE(IStream) StgStreamImpl_Vtbl = { StgStreamImpl_QueryInterface, StgStreamImpl_AddRef, StgStreamImpl_Release, StgStreamImpl_Read, StgStreamImpl_Write, StgStreamImpl_Seek, StgStreamImpl_SetSize, StgStreamImpl_CopyTo, StgStreamImpl_Commit, StgStreamImpl_Revert, StgStreamImpl_LockRegion, StgStreamImpl_UnlockRegion, StgStreamImpl_Stat, StgStreamImpl_Clone }; /****************************************************************************** ** StgStreamImpl implementation */ /*** * This is the constructor for the StgStreamImpl class. * * Params: * parentStorage - Pointer to the storage that contains the stream to open * ownerProperty - Index of the property that points to this stream. */ StgStreamImpl* StgStreamImpl_Construct( StorageBaseImpl* parentStorage, ULONG ownerProperty) { StgStreamImpl* newStream; newStream = HeapAlloc(GetProcessHeap(), 0, sizeof(StgStreamImpl)); if (newStream!=0) { /* * Set-up the virtual function table and reference count. */ newStream->lpvtbl = &StgStreamImpl_Vtbl; newStream->ref = 0; /* * We want to nail-down the reference to the storage in case the * stream out-lives the storage in the client application. */ newStream->parentStorage = parentStorage; IStorage_AddRef((IStorage*)newStream->parentStorage); newStream->ownerProperty = ownerProperty; /* * Start the stream at the begining. */ newStream->currentPosition.HighPart = 0; newStream->currentPosition.LowPart = 0; /* * Initialize the rest of the data. */ newStream->streamSize.HighPart = 0; newStream->streamSize.LowPart = 0; newStream->bigBlockChain = 0; newStream->smallBlockChain = 0; /* * Read the size from the property and determine if the blocks forming * this stream are large or small. */ StgStreamImpl_OpenBlockChain(newStream); } return newStream; } /*** * This is the destructor of the StgStreamImpl class. * * This method will clean-up all the resources used-up by the given StgStreamImpl * class. The pointer passed-in to this function will be freed and will not * be valid anymore. */ void StgStreamImpl_Destroy(StgStreamImpl* This) { /* * Release the reference we are holding on the parent storage. */ IStorage_Release((IStorage*)This->parentStorage); This->parentStorage = 0; /* * Make sure we clean-up the block chain stream objects that we were using. */ if (This->bigBlockChain != 0) { BlockChainStream_Destroy(This->bigBlockChain); This->bigBlockChain = 0; } if (This->smallBlockChain != 0) { SmallBlockChainStream_Destroy(This->smallBlockChain); This->smallBlockChain = 0; } /* * Finally, free the memory used-up by the class. */ HeapFree(GetProcessHeap(), 0, This); } /*** * This implements the IUnknown method QueryInterface for this * class */ HRESULT WINAPI StgStreamImpl_QueryInterface( IStream* iface, REFIID riid, /* [in] */ void** ppvObject) /* [iid_is][out] */ { StgStreamImpl* const This=(StgStreamImpl*)iface; /* * Perform a sanity check on the parameters. */ if (ppvObject==0) return E_INVALIDARG; /* * Initialize the return parameter. */ *ppvObject = 0; /* * Compare the riid with the interface IDs implemented by this object. */ if (memcmp(&IID_IUnknown, riid, sizeof(IID_IUnknown)) == 0) { *ppvObject = (IStream*)This; } else if (memcmp(&IID_IStorage, riid, sizeof(IID_IStream)) == 0) { *ppvObject = (IStream*)This; } /* * Check that we obtained an interface. */ if ((*ppvObject)==0) return E_NOINTERFACE; /* * Query Interface always increases the reference count by one when it is * successful */ StgStreamImpl_AddRef(iface); return S_OK;; } /*** * This implements the IUnknown method AddRef for this * class */ ULONG WINAPI StgStreamImpl_AddRef( IStream* iface) { StgStreamImpl* const This=(StgStreamImpl*)iface; This->ref++; return This->ref; } /*** * This implements the IUnknown method Release for this * class */ ULONG WINAPI StgStreamImpl_Release( IStream* iface) { StgStreamImpl* const This=(StgStreamImpl*)iface; ULONG newRef; This->ref--; newRef = This->ref; /* * If the reference count goes down to 0, perform suicide. */ if (newRef==0) { StgStreamImpl_Destroy(This); } return newRef; } /*** * This method will open the block chain pointed by the property * that describes the stream. * If the stream's size is null, no chain is opened. */ void StgStreamImpl_OpenBlockChain( StgStreamImpl* This) { StgProperty curProperty; BOOL readSucessful; /* * Make sure no old object is staying behind. */ if (This->smallBlockChain != 0) { SmallBlockChainStream_Destroy(This->smallBlockChain); This->smallBlockChain = 0; } if (This->bigBlockChain != 0) { BlockChainStream_Destroy(This->bigBlockChain); This->bigBlockChain = 0; } /* * Read the information from the property. */ readSucessful = StorageImpl_ReadProperty(This->parentStorage->ancestorStorage, This->ownerProperty, &curProperty); if (readSucessful) { This->streamSize = curProperty.size; /* * This code supports only streams that are <32 bits in size. */ assert(This->streamSize.HighPart == 0); if(curProperty.startingBlock == BLOCK_END_OF_CHAIN) { assert( (This->streamSize.HighPart == 0) && (This->streamSize.LowPart == 0) ); } else { if ( (This->streamSize.HighPart == 0) && (This->streamSize.LowPart < LIMIT_TO_USE_SMALL_BLOCK) ) { This->smallBlockChain = SmallBlockChainStream_Construct( This->parentStorage->ancestorStorage, This->ownerProperty); } else { This->bigBlockChain = BlockChainStream_Construct( This->parentStorage->ancestorStorage, NULL, This->ownerProperty); } } } } /*** * This method is part of the ISequentialStream interface. * * If reads a block of information from the stream at the current * position. It then moves the current position at the end of the * read block * * See the documentation of ISequentialStream for more info. */ HRESULT WINAPI StgStreamImpl_Read( IStream* iface, void* pv, /* [length_is][size_is][out] */ ULONG cb, /* [in] */ ULONG* pcbRead) /* [out] */ { StgStreamImpl* const This=(StgStreamImpl*)iface; ULONG bytesReadBuffer; ULONG bytesToReadFromBuffer; /* * If the caller is not interested in the nubmer of bytes read, * we use another buffer to avoid "if" statements in the code. */ if (pcbRead==0) pcbRead = &bytesReadBuffer; /* * Using the known size of the stream, calculate the number of bytes * to read from the block chain */ bytesToReadFromBuffer = MIN( This->streamSize.LowPart - This->currentPosition.LowPart, cb); /* * Depending on the type of chain that was opened when the stream was constructed, * we delegate the work to the method that read the block chains. */ if (This->smallBlockChain!=0) { SmallBlockChainStream_ReadAt(This->smallBlockChain, This->currentPosition, bytesToReadFromBuffer, pv, pcbRead); } else if (This->bigBlockChain!=0) { BlockChainStream_ReadAt(This->bigBlockChain, This->currentPosition, bytesToReadFromBuffer, pv, pcbRead); } else assert(FALSE); /* * We should always be able to read the proper amount of data from the * chain. */ assert(bytesToReadFromBuffer == *pcbRead); /* * Advance the pointer for the number of positions read. */ This->currentPosition.LowPart += *pcbRead; /* * The function returns S_OK if the buffer was filled completely * it returns S_FALSE if the end of the stream is reached before the * buffer is filled */ if(*pcbRead == cb) return S_OK; return S_FALSE; } /*** * This method is part of the ISequentialStream interface. * * It writes a block of information to the stream at the current * position. It then moves the current position at the end of the * written block. If the stream is too small to fit the block, * the stream is grown to fit. * * See the documentation of ISequentialStream for more info. */ HRESULT WINAPI StgStreamImpl_Write( IStream* iface, const void* pv, /* [size_is][in] */ ULONG cb, /* [in] */ ULONG* pcbWritten) /* [out] */ { StgStreamImpl* const This=(StgStreamImpl*)iface; ULARGE_INTEGER newSize; ULONG bytesWritten = 0; /* * If the caller is not interested in the number of bytes written, * we use another buffer to avoid "if" statements in the code. */ if (pcbWritten == 0) pcbWritten = &bytesWritten; if (cb == 0) { return S_OK; } else { newSize.HighPart = 0; newSize.LowPart = This->currentPosition.LowPart + cb; } /* * Verify if we need to grow the stream */ if (newSize.LowPart > This->streamSize.LowPart) { /* grow stream */ StgStreamImpl_SetSize(iface, newSize); } /* * Depending on the type of chain that was opened when the stream was constructed, * we delegate the work to the method that readwrites to the block chains. */ if (This->smallBlockChain!=0) { SmallBlockChainStream_WriteAt(This->smallBlockChain, This->currentPosition, cb, pv, pcbWritten); } else if (This->bigBlockChain!=0) { BlockChainStream_WriteAt(This->bigBlockChain, This->currentPosition, cb, pv, pcbWritten); } else assert(FALSE); /* * Advance the position pointer for the number of positions written. */ This->currentPosition.LowPart += *pcbWritten; return S_OK; } /*** * This method is part of the IStream interface. * * It will move the current stream pointer according to the parameters * given. * * See the documentation of IStream for more info. */ HRESULT WINAPI StgStreamImpl_Seek( IStream* iface, LARGE_INTEGER dlibMove, /* [in] */ DWORD dwOrigin, /* [in] */ ULARGE_INTEGER* plibNewPosition) /* [out] */ { StgStreamImpl* const This=(StgStreamImpl*)iface; ULARGE_INTEGER newPosition; /* * The caller is allowed to pass in NULL as the new position return value. * If it happens, we assign it to a dynamic variable to avoid special cases * in the code below. */ if (plibNewPosition == 0) { plibNewPosition = &newPosition; } /* * The file pointer is moved depending on the given "function" * parameter. */ switch (dwOrigin) { case STREAM_SEEK_SET: plibNewPosition->HighPart = 0; plibNewPosition->LowPart = 0; break; case STREAM_SEEK_CUR: *plibNewPosition = This->currentPosition; break; case STREAM_SEEK_END: *plibNewPosition = This->streamSize; break; default: return STG_E_INVALIDFUNCTION; } /* * We don't support files with offsets of 64 bits. */ assert(dlibMove.HighPart == 0); /* * Check if we end-up before the beginning of the file. That should trigger an * error. */ if ( (dlibMove.LowPart<0) && (plibNewPosition->LowPart < (ULONG)(-dlibMove.LowPart)) ) { /* * I don't know what error to send there. */ return E_FAIL; } /* * Move the actual file pointer * If the file pointer ends-up after the end of the stream, the next Write operation will * make the file larger. This is how it is documented. */ plibNewPosition->LowPart += dlibMove.LowPart; This->currentPosition = *plibNewPosition; return S_OK; } /*** * This method is part of the IStream interface. * * It will change the size of a stream. * * TODO: Switch from small blocks to big blocks and vice versa. * * See the documentation of IStream for more info. */ HRESULT WINAPI StgStreamImpl_SetSize( IStream* iface, ULARGE_INTEGER libNewSize) /* [in] */ { StgStreamImpl* const This=(StgStreamImpl*)iface; StgProperty curProperty; BOOL Success; /* * As documented. */ if (libNewSize.HighPart != 0) return STG_E_INVALIDFUNCTION; if (This->streamSize.LowPart == libNewSize.LowPart) return S_OK; /* * This will happen if we're creating a stream */ if ((This->smallBlockChain == 0) && (This->bigBlockChain == 0)) { if (libNewSize.LowPart < LIMIT_TO_USE_SMALL_BLOCK) { This->smallBlockChain = SmallBlockChainStream_Construct( This->parentStorage->ancestorStorage, This->ownerProperty); } else { This->bigBlockChain = BlockChainStream_Construct( This->parentStorage->ancestorStorage, NULL, This->ownerProperty); } } /* * Read this stream's property to see if it's small blocks or big blocks */ Success = StorageImpl_ReadProperty(This->parentStorage->ancestorStorage, This->ownerProperty, &curProperty); /* * Determine if we have to switch from small to big blocks or vice versa */ if (curProperty.size.LowPart < LIMIT_TO_USE_SMALL_BLOCK) { if (libNewSize.LowPart >= LIMIT_TO_USE_SMALL_BLOCK) { /* * Transform the small block chain into a big block chain */ This->bigBlockChain = Storage32Impl_SmallBlocksToBigBlocks( This->parentStorage->ancestorStorage, &This->smallBlockChain); } } if (This->smallBlockChain!=0) { Success = SmallBlockChainStream_SetSize(This->smallBlockChain, libNewSize); } else { Success = BlockChainStream_SetSize(This->bigBlockChain, libNewSize); } /* * Write to the property the new information about this stream */ Success = StorageImpl_ReadProperty(This->parentStorage->ancestorStorage, This->ownerProperty, &curProperty); curProperty.size.HighPart = libNewSize.HighPart; curProperty.size.LowPart = libNewSize.LowPart; if (Success) { StorageImpl_WriteProperty(This->parentStorage->ancestorStorage, This->ownerProperty, &curProperty); } This->streamSize = libNewSize; return S_OK; } HRESULT WINAPI StgStreamImpl_CopyTo( IStream* iface, IStream* pstm, /* [unique][in] */ ULARGE_INTEGER cb, /* [in] */ ULARGE_INTEGER* pcbRead, /* [out] */ ULARGE_INTEGER* pcbWritten) /* [out] */ { return E_NOTIMPL; } /*** * This method is part of the IStream interface. * * For streams contained in structured storages, this method * does nothing. This is what the documentation tells us. * * See the documentation of IStream for more info. */ HRESULT WINAPI StgStreamImpl_Commit( IStream* iface, DWORD grfCommitFlags) /* [in] */ { return S_OK; } /*** * This method is part of the IStream interface. * * For streams contained in structured storages, this method * does nothing. This is what the documentation tells us. * * See the documentation of IStream for more info. */ HRESULT WINAPI StgStreamImpl_Revert( IStream* iface) { return S_OK; } HRESULT WINAPI StgStreamImpl_LockRegion( IStream* iface, ULARGE_INTEGER libOffset, /* [in] */ ULARGE_INTEGER cb, /* [in] */ DWORD dwLockType) /* [in] */ { return E_NOTIMPL; } HRESULT WINAPI StgStreamImpl_UnlockRegion( IStream* iface, ULARGE_INTEGER libOffset, /* [in] */ ULARGE_INTEGER cb, /* [in] */ DWORD dwLockType) /* [in] */ { return E_NOTIMPL; } /*** * This method is part of the IStream interface. * * This method returns information about the current * stream. * * See the documentation of IStream for more info. */ HRESULT WINAPI StgStreamImpl_Stat( IStream* iface, STATSTG* pstatstg, /* [out] */ DWORD grfStatFlag) /* [in] */ { StgStreamImpl* const This=(StgStreamImpl*)iface; StgProperty curProperty; BOOL readSucessful; /* * Read the information from the property. */ readSucessful = StorageImpl_ReadProperty(This->parentStorage->ancestorStorage, This->ownerProperty, &curProperty); if (readSucessful) { StorageUtl_CopyPropertyToSTATSTG(pstatstg, &curProperty, grfStatFlag); return S_OK; } return E_FAIL; } HRESULT WINAPI StgStreamImpl_Clone( IStream* iface, IStream** ppstm) /* [out] */ { return E_NOTIMPL; }