Sweden-Number/ole/stg_stream.c

730 lines
17 KiB
C

/*
* 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 <assert.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include "winbase.h"
#include "winerror.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;
}