Sweden-Number/dlls/ole32/hglobalstream.c

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/*
* HGLOBAL Stream implementation
*
* This file contains the implementation of the stream interface
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* for streams contained supported by an HGLOBAL pointer.
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*
* Copyright 1999 Francis Beaudet
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*/
#include "config.h"
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#include <assert.h>
#include <stdlib.h>
#include <stdarg.h>
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#include <stdio.h>
#include <string.h>
#define COBJMACROS
#define NONAMELESSUNION
#define NONAMELESSSTRUCT
#include "windef.h"
#include "winbase.h"
#include "winuser.h"
#include "objbase.h"
#include "ole2.h"
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#include "winerror.h"
#include "winreg.h"
#include "winternl.h"
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#include "wine/debug.h"
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WINE_DEFAULT_DEBUG_CHANNEL(storage);
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/****************************************************************************
* HGLOBALStreamImpl definition.
*
* This class imlements the IStream inteface and represents a stream
* supported by an HGLOBAL pointer.
*/
struct HGLOBALStreamImpl
{
const IStreamVtbl *lpVtbl; /* Needs to be the first item in the struct
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* since we want to cast this in an IStream pointer */
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/*
* Reference count
*/
ULONG ref;
/*
* Support for the stream
*/
HGLOBAL supportHandle;
/*
* This flag is TRUE if the HGLOBAL is destroyed when the stream
* is finally released.
*/
BOOL deleteOnRelease;
/*
* Helper variable that contains the size of the stream
*/
ULARGE_INTEGER streamSize;
/*
* This is the current position of the cursor in the stream
*/
ULARGE_INTEGER currentPosition;
};
typedef struct HGLOBALStreamImpl HGLOBALStreamImpl;
/***
* This is the destructor of the HGLOBALStreamImpl class.
*
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* This method will clean-up all the resources used-up by the given HGLOBALStreamImpl
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* class. The pointer passed-in to this function will be freed and will not
* be valid anymore.
*/
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static void HGLOBALStreamImpl_Destroy(HGLOBALStreamImpl* This)
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{
TRACE("(%p)\n", This);
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/*
* Release the HGlobal if the constructor asked for that.
*/
if (This->deleteOnRelease)
{
GlobalFree(This->supportHandle);
This->supportHandle=0;
}
/*
* Finally, free the memory used-up by the class.
*/
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HeapFree(GetProcessHeap(), 0, This);
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}
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/***
* This implements the IUnknown method AddRef for this
* class
*/
static ULONG WINAPI HGLOBALStreamImpl_AddRef(
IStream* iface)
{
HGLOBALStreamImpl* const This=(HGLOBALStreamImpl*)iface;
return InterlockedIncrement(&This->ref);
}
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/***
* This implements the IUnknown method QueryInterface for this
* class
*/
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static HRESULT WINAPI HGLOBALStreamImpl_QueryInterface(
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IStream* iface,
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REFIID riid, /* [in] */
void** ppvObject) /* [iid_is][out] */
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{
HGLOBALStreamImpl* const This=(HGLOBALStreamImpl*)iface;
/*
* Perform a sanity check on the parameters.
*/
if (ppvObject==0)
return E_INVALIDARG;
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/*
* Initialize the return parameter.
*/
*ppvObject = 0;
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/*
* Compare the riid with the interface IDs implemented by this object.
*/
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if (memcmp(&IID_IUnknown, riid, sizeof(IID_IUnknown)) == 0)
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{
*ppvObject = (IStream*)This;
}
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else if (memcmp(&IID_IStream, riid, sizeof(IID_IStream)) == 0)
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{
*ppvObject = (IStream*)This;
}
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/*
* Check that we obtained an interface.
*/
if ((*ppvObject)==0)
return E_NOINTERFACE;
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/*
* Query Interface always increases the reference count by one when it is
* successful
*/
HGLOBALStreamImpl_AddRef(iface);
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return S_OK;
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}
/***
* This implements the IUnknown method Release for this
* class
*/
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static ULONG WINAPI HGLOBALStreamImpl_Release(
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IStream* iface)
{
HGLOBALStreamImpl* const This=(HGLOBALStreamImpl*)iface;
ULONG newRef;
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newRef = InterlockedDecrement(&This->ref);
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/*
* If the reference count goes down to 0, perform suicide.
*/
if (newRef==0)
{
HGLOBALStreamImpl_Destroy(This);
}
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return newRef;
}
/***
* 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.
*/
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static HRESULT WINAPI HGLOBALStreamImpl_Read(
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IStream* iface,
void* pv, /* [length_is][size_is][out] */
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ULONG cb, /* [in] */
ULONG* pcbRead) /* [out] */
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{
HGLOBALStreamImpl* const This=(HGLOBALStreamImpl*)iface;
void* supportBuffer;
ULONG bytesReadBuffer;
ULONG bytesToReadFromBuffer;
TRACE("(%p, %p, %ld, %p)\n", iface,
pv, cb, pcbRead);
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/*
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* 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;
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/*
* Using the known size of the stream, calculate the number of bytes
* to read from the block chain
*/
bytesToReadFromBuffer = min( This->streamSize.u.LowPart - This->currentPosition.u.LowPart, cb);
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/*
* Lock the buffer in position and copy the data.
*/
supportBuffer = GlobalLock(This->supportHandle);
memcpy(pv, (char *) supportBuffer+This->currentPosition.u.LowPart, bytesToReadFromBuffer);
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/*
* Move the current position to the new position
*/
This->currentPosition.u.LowPart+=bytesToReadFromBuffer;
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/*
* Return the number of bytes read.
*/
*pcbRead = bytesToReadFromBuffer;
/*
* Cleanup
*/
GlobalUnlock(This->supportHandle);
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/*
* 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;
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return S_FALSE;
}
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/***
* 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.
*/
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static HRESULT WINAPI HGLOBALStreamImpl_Write(
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IStream* iface,
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const void* pv, /* [size_is][in] */
ULONG cb, /* [in] */
ULONG* pcbWritten) /* [out] */
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{
HGLOBALStreamImpl* const This=(HGLOBALStreamImpl*)iface;
void* supportBuffer;
ULARGE_INTEGER newSize;
ULONG bytesWritten = 0;
TRACE("(%p, %p, %ld, %p)\n", iface,
pv, cb, pcbWritten);
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/*
* 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;
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if (cb == 0)
{
return S_OK;
}
else
{
newSize.u.HighPart = 0;
newSize.u.LowPart = This->currentPosition.u.LowPart + cb;
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}
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/*
* Verify if we need to grow the stream
*/
if (newSize.u.LowPart > This->streamSize.u.LowPart)
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{
/* grow stream */
IStream_SetSize(iface, newSize);
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}
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/*
* Lock the buffer in position and copy the data.
*/
supportBuffer = GlobalLock(This->supportHandle);
memcpy((char *) supportBuffer+This->currentPosition.u.LowPart, pv, cb);
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/*
* Move the current position to the new position
*/
This->currentPosition.u.LowPart+=cb;
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/*
* Return the number of bytes read.
*/
*pcbWritten = cb;
/*
* Cleanup
*/
GlobalUnlock(This->supportHandle);
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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.
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*/
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static HRESULT WINAPI HGLOBALStreamImpl_Seek(
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IStream* iface,
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LARGE_INTEGER dlibMove, /* [in] */
DWORD dwOrigin, /* [in] */
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ULARGE_INTEGER* plibNewPosition) /* [out] */
{
HGLOBALStreamImpl* const This=(HGLOBALStreamImpl*)iface;
ULARGE_INTEGER newPosition;
TRACE("(%p, %lx%08lx, %ld, %p)\n", iface, dlibMove.u.HighPart,
dlibMove.u.LowPart, dwOrigin, plibNewPosition);
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/*
* The file pointer is moved depending on the given "function"
* parameter.
*/
switch (dwOrigin)
{
case STREAM_SEEK_SET:
newPosition.u.HighPart = 0;
newPosition.u.LowPart = 0;
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break;
case STREAM_SEEK_CUR:
newPosition = This->currentPosition;
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break;
case STREAM_SEEK_END:
newPosition = This->streamSize;
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break;
default:
return STG_E_INVALIDFUNCTION;
}
/*
* 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.
*/
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if (dlibMove.QuadPart < 0 && newPosition.QuadPart < -dlibMove.QuadPart) return STG_E_INVALIDFUNCTION;
newPosition.QuadPart = RtlLargeIntegerAdd(newPosition.QuadPart, dlibMove.QuadPart);
if (plibNewPosition) *plibNewPosition = newPosition;
This->currentPosition = newPosition;
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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.
*/
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static HRESULT WINAPI HGLOBALStreamImpl_SetSize(
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IStream* iface,
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ULARGE_INTEGER libNewSize) /* [in] */
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{
HGLOBALStreamImpl* const This=(HGLOBALStreamImpl*)iface;
HGLOBAL supportHandle;
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TRACE("(%p, %ld)\n", iface, libNewSize.u.LowPart);
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/*
* As documented.
*/
if (libNewSize.u.HighPart != 0)
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return STG_E_INVALIDFUNCTION;
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if (This->streamSize.u.LowPart == libNewSize.u.LowPart)
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return S_OK;
/*
* Re allocate the HGlobal to fit the new size of the stream.
*/
supportHandle = GlobalReAlloc(This->supportHandle, libNewSize.u.LowPart, 0);
if (supportHandle == 0)
return STG_E_MEDIUMFULL;
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This->supportHandle = supportHandle;
This->streamSize.u.LowPart = libNewSize.u.LowPart;
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return S_OK;
}
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/***
* This method is part of the IStream interface.
*
* It will copy the 'cb' Bytes to 'pstm' IStream.
*
* See the documentation of IStream for more info.
*/
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static HRESULT WINAPI HGLOBALStreamImpl_CopyTo(
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IStream* iface,
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IStream* pstm, /* [unique][in] */
ULARGE_INTEGER cb, /* [in] */
ULARGE_INTEGER* pcbRead, /* [out] */
ULARGE_INTEGER* pcbWritten) /* [out] */
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{
HRESULT hr = S_OK;
BYTE tmpBuffer[128];
ULONG bytesRead, bytesWritten, copySize;
ULARGE_INTEGER totalBytesRead;
ULARGE_INTEGER totalBytesWritten;
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TRACE("(%p, %p, %ld, %p, %p)\n", iface, pstm,
cb.u.LowPart, pcbRead, pcbWritten);
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/*
* Sanity check
*/
if ( pstm == 0 )
return STG_E_INVALIDPOINTER;
totalBytesRead.u.LowPart = totalBytesRead.u.HighPart = 0;
totalBytesWritten.u.LowPart = totalBytesWritten.u.HighPart = 0;
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/*
* use stack to store data temporarly
* there is surely more performant way of doing it, for now this basic
* implementation will do the job
*/
while ( cb.u.LowPart > 0 )
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{
if ( cb.u.LowPart >= 128 )
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copySize = 128;
else
copySize = cb.u.LowPart;
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IStream_Read(iface, tmpBuffer, copySize, &bytesRead);
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totalBytesRead.u.LowPart += bytesRead;
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IStream_Write(pstm, tmpBuffer, bytesRead, &bytesWritten);
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totalBytesWritten.u.LowPart += bytesWritten;
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/*
* Check that read & write operations were succesfull
*/
if (bytesRead != bytesWritten)
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{
hr = STG_E_MEDIUMFULL;
break;
}
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if (bytesRead!=copySize)
cb.u.LowPart = 0;
else
cb.u.LowPart -= bytesRead;
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}
/*
* Update number of bytes read and written
*/
if (pcbRead)
{
pcbRead->u.LowPart = totalBytesRead.u.LowPart;
pcbRead->u.HighPart = totalBytesRead.u.HighPart;
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}
if (pcbWritten)
{
pcbWritten->u.LowPart = totalBytesWritten.u.LowPart;
pcbWritten->u.HighPart = totalBytesWritten.u.HighPart;
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}
return hr;
}
/***
* This method is part of the IStream interface.
*
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* For streams supported by HGLOBALS, this function does nothing.
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* This is what the documentation tells us.
*
* See the documentation of IStream for more info.
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*/
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static HRESULT WINAPI HGLOBALStreamImpl_Commit(
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IStream* iface,
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DWORD grfCommitFlags) /* [in] */
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{
return S_OK;
}
/***
* This method is part of the IStream interface.
*
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* For streams supported by HGLOBALS, this function does nothing.
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* This is what the documentation tells us.
*
* See the documentation of IStream for more info.
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*/
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static HRESULT WINAPI HGLOBALStreamImpl_Revert(
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IStream* iface)
{
return S_OK;
}
/***
* This method is part of the IStream interface.
*
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* For streams supported by HGLOBALS, this function does nothing.
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* This is what the documentation tells us.
*
* See the documentation of IStream for more info.
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*/
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static HRESULT WINAPI HGLOBALStreamImpl_LockRegion(
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IStream* iface,
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ULARGE_INTEGER libOffset, /* [in] */
ULARGE_INTEGER cb, /* [in] */
DWORD dwLockType) /* [in] */
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{
return S_OK;
}
/*
* This method is part of the IStream interface.
*
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* For streams supported by HGLOBALS, this function does nothing.
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* This is what the documentation tells us.
*
* See the documentation of IStream for more info.
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*/
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static HRESULT WINAPI HGLOBALStreamImpl_UnlockRegion(
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IStream* iface,
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ULARGE_INTEGER libOffset, /* [in] */
ULARGE_INTEGER cb, /* [in] */
DWORD dwLockType) /* [in] */
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{
return S_OK;
}
/***
* This method is part of the IStream interface.
*
* This method returns information about the current
* stream.
*
* See the documentation of IStream for more info.
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*/
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static HRESULT WINAPI HGLOBALStreamImpl_Stat(
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IStream* iface,
STATSTG* pstatstg, /* [out] */
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DWORD grfStatFlag) /* [in] */
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{
HGLOBALStreamImpl* const This=(HGLOBALStreamImpl*)iface;
memset(pstatstg, 0, sizeof(STATSTG));
pstatstg->pwcsName = NULL;
pstatstg->type = STGTY_STREAM;
pstatstg->cbSize = This->streamSize;
return S_OK;
}
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static HRESULT WINAPI HGLOBALStreamImpl_Clone(
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IStream* iface,
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IStream** ppstm) /* [out] */
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{
ULARGE_INTEGER dummy;
LARGE_INTEGER offset;
HRESULT hr;
HGLOBALStreamImpl* const This=(HGLOBALStreamImpl*)iface;
TRACE(" Cloning %p (deleteOnRelease=%d seek position=%ld)\n",iface,This->deleteOnRelease,(long)This->currentPosition.QuadPart);
hr=CreateStreamOnHGlobal(This->supportHandle, FALSE, ppstm);
if(FAILED(hr))
return hr;
offset.QuadPart=(LONGLONG)This->currentPosition.QuadPart;
HGLOBALStreamImpl_Seek(*ppstm,offset,STREAM_SEEK_SET,&dummy);
return S_OK;
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}
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/*
* Virtual function table for the HGLOBALStreamImpl class.
*/
static const IStreamVtbl HGLOBALStreamImpl_Vtbl =
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{
HGLOBALStreamImpl_QueryInterface,
HGLOBALStreamImpl_AddRef,
HGLOBALStreamImpl_Release,
HGLOBALStreamImpl_Read,
HGLOBALStreamImpl_Write,
HGLOBALStreamImpl_Seek,
HGLOBALStreamImpl_SetSize,
HGLOBALStreamImpl_CopyTo,
HGLOBALStreamImpl_Commit,
HGLOBALStreamImpl_Revert,
HGLOBALStreamImpl_LockRegion,
HGLOBALStreamImpl_UnlockRegion,
HGLOBALStreamImpl_Stat,
HGLOBALStreamImpl_Clone
};
/******************************************************************************
** HGLOBALStreamImpl implementation
*/
/***
* This is the constructor for the HGLOBALStreamImpl class.
*
* Params:
* hGlobal - Handle that will support the stream. can be NULL.
* fDeleteOnRelease - Flag set to TRUE if the HGLOBAL will be released
* when the IStream object is destroyed.
*/
HGLOBALStreamImpl* HGLOBALStreamImpl_Construct(
HGLOBAL hGlobal,
BOOL fDeleteOnRelease)
{
HGLOBALStreamImpl* newStream;
newStream = HeapAlloc(GetProcessHeap(), 0, sizeof(HGLOBALStreamImpl));
if (newStream!=0)
{
/*
* Set-up the virtual function table and reference count.
*/
newStream->lpVtbl = &HGLOBALStreamImpl_Vtbl;
newStream->ref = 0;
/*
* Initialize the support.
*/
newStream->supportHandle = hGlobal;
newStream->deleteOnRelease = fDeleteOnRelease;
/*
* This method will allocate a handle if one is not supplied.
*/
if (!newStream->supportHandle)
{
newStream->supportHandle = GlobalAlloc(GMEM_MOVEABLE | GMEM_NODISCARD |
GMEM_SHARE, 0);
}
/*
* Start the stream at the beginning.
*/
newStream->currentPosition.u.HighPart = 0;
newStream->currentPosition.u.LowPart = 0;
/*
* Initialize the size of the stream to the size of the handle.
*/
newStream->streamSize.u.HighPart = 0;
newStream->streamSize.u.LowPart = GlobalSize(newStream->supportHandle);
}
return newStream;
}
/***********************************************************************
* CreateStreamOnHGlobal [OLE32.@]
*/
HRESULT WINAPI CreateStreamOnHGlobal(
HGLOBAL hGlobal,
BOOL fDeleteOnRelease,
LPSTREAM* ppstm)
{
HGLOBALStreamImpl* newStream;
newStream = HGLOBALStreamImpl_Construct(hGlobal,
fDeleteOnRelease);
if (newStream!=NULL)
{
return IUnknown_QueryInterface((IUnknown*)newStream,
&IID_IStream,
(void**)ppstm);
}
return E_OUTOFMEMORY;
}
/***********************************************************************
* GetHGlobalFromStream [OLE32.@]
*/
HRESULT WINAPI GetHGlobalFromStream(IStream* pstm, HGLOBAL* phglobal)
{
HGLOBALStreamImpl* pStream;
if (pstm == NULL)
return E_INVALIDARG;
pStream = (HGLOBALStreamImpl*) pstm;
/*
* Verify that the stream object was created with CreateStreamOnHGlobal.
*/
if (pStream->lpVtbl == &HGLOBALStreamImpl_Vtbl)
*phglobal = pStream->supportHandle;
else
{
*phglobal = 0;
return E_INVALIDARG;
}
return S_OK;
}