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757 lines
20 KiB
757 lines
20 KiB
//
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// dmstrm.cpp
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//
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// Copyright (c) 1995-2000 Microsoft Corporation
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//
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#include "debug.h"
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#include "dmusicc.h"
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#include "..\shared\dmstrm.h"
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#include "..\shared\validate.h"
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/////////////////////////////////////////////////////////////////////////////
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// AllocDIrectMusicStream
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STDAPI AllocDirectMusicStream(IStream* pIStream, IDMStream** ppIDMStream)
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{
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if(pIStream == NULL || ppIDMStream == NULL)
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{
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return E_INVALIDARG;
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}
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if((*ppIDMStream = (IDMStream*) new CDirectMusicStream()) == NULL)
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{
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return E_OUTOFMEMORY;
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}
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((CDirectMusicStream*)*ppIDMStream)->Init(pIStream);
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return S_OK;
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}
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//////////////////////////////////////////////////////////////////////
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// CDirectMusicStream::CDirectMusicStream
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CDirectMusicStream::CDirectMusicStream() :
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m_cRef(1),
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m_pStream(NULL)
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{
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}
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//////////////////////////////////////////////////////////////////////
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// CDirectMusicStream::~CDirectMusicStream
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CDirectMusicStream::~CDirectMusicStream()
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{
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if(m_pStream != NULL)
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{
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m_pStream->Release();
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}
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}
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//////////////////////////////////////////////////////////////////////
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// CDirectMusicStream::Init
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STDMETHODIMP CDirectMusicStream::Init(IStream* pStream)
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{
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SetStream(pStream);
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return S_OK;
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}
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//////////////////////////////////////////////////////////////////////
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// IUnknown
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//////////////////////////////////////////////////////////////////////
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// CDirectMusicStream::QueryInterface
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STDMETHODIMP CDirectMusicStream::QueryInterface(const IID &iid, void **ppv)
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{
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V_INAME(CDirectMusicStream::QueryInterface);
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V_PTRPTR_WRITE(ppv);
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V_REFGUID(iid);
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if(iid == IID_IUnknown || iid == IID_IDMStream)
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{
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*ppv = static_cast<IDMStream*>(this);
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}
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else
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{
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*ppv = NULL;
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return E_NOINTERFACE;
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}
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reinterpret_cast<IUnknown*>(this)->AddRef();
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return S_OK;
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}
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//////////////////////////////////////////////////////////////////////
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// CDirectMusicStream::AddRef
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STDMETHODIMP_(ULONG) CDirectMusicStream::AddRef()
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{
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return InterlockedIncrement(&m_cRef);
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}
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//////////////////////////////////////////////////////////////////////
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// CDirectMusicStream::Release
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STDMETHODIMP_(ULONG) CDirectMusicStream::Release()
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{
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if(!InterlockedDecrement(&m_cRef))
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{
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delete this;
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return 0;
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}
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return m_cRef;
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}
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//////////////////////////////////////////////////////////////////////
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// CDirectMusicStream::SetStream
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STDMETHODIMP CDirectMusicStream::SetStream(IStream* pStream)
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{
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if(m_pStream != NULL)
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{
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m_pStream->Release();
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}
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m_pStream = pStream;
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if(m_pStream != NULL)
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{
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m_pStream->AddRef();
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}
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return S_OK;
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}
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//////////////////////////////////////////////////////////////////////
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// CDirectMusicStream::GetStream
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STDMETHODIMP_(IStream*) CDirectMusicStream::GetStream()
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{
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if(m_pStream != NULL)
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{
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m_pStream->AddRef();
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}
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return m_pStream;
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}
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//////////////////////////////////////////////////////////////////////
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// IDMStream
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//////////////////////////////////////////////////////////////////////
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// CDirectMusicStream::Descend
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STDMETHODIMP CDirectMusicStream::Descend(LPMMCKINFO lpck, LPMMCKINFO lpckParent, UINT wFlags)
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{
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assert(lpck);
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FOURCC ckidFind; // Chunk ID to find (or NULL)
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FOURCC fccTypeFind; // Form/list type to find (or NULL)
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// Figure out what chunk id and form/list type for which to search
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if(wFlags & MMIO_FINDCHUNK)
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{
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ckidFind = lpck->ckid;
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fccTypeFind = NULL;
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}
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else if(wFlags & MMIO_FINDRIFF)
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{
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ckidFind = FOURCC_RIFF;
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fccTypeFind = lpck->fccType;
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}
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else if(wFlags & MMIO_FINDLIST)
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{
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ckidFind = FOURCC_LIST;
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fccTypeFind = lpck->fccType;
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}
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else
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{
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ckidFind = fccTypeFind = NULL;
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}
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lpck->dwFlags = 0L;
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for(;;)
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{
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HRESULT hr;
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LARGE_INTEGER li;
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ULARGE_INTEGER uli;
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ULONG cbRead;
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// Read the chunk header
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hr = m_pStream->Read(lpck, 2 * sizeof(DWORD), &cbRead);
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if (FAILED(hr) || (cbRead != 2 * sizeof(DWORD)))
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{
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Trace(3,"Warning: Reached end of file.\n");
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return DMUS_E_DESCEND_CHUNK_FAIL;
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}
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// Store the offset of the data part of the chunk
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li.QuadPart = 0;
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hr = m_pStream->Seek(li, STREAM_SEEK_CUR, &uli);
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if(FAILED(hr))
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{
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Trace(1,"Error: Unable to read file.\n");
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return DMUS_E_CANNOTSEEK;
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}
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else
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{
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lpck->dwDataOffset = uli.LowPart;
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}
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// See if the chunk is within the parent chunk (if given)
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if((lpckParent != NULL) &&
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(lpck->dwDataOffset - 8L >=
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lpckParent->dwDataOffset + lpckParent->cksize))
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{
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// This is not really a failure, just indicating we've reached the end of the list.
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return DMUS_E_DESCEND_CHUNK_FAIL;
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}
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// If the chunk is a 'RIFF' or 'LIST' chunk, read the
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// form type or list type
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if((lpck->ckid == FOURCC_RIFF) || (lpck->ckid == FOURCC_LIST))
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{
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hr = m_pStream->Read(&lpck->fccType, sizeof(DWORD), &cbRead);
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if(FAILED(hr) || (cbRead != sizeof(DWORD)))
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{
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Trace(1,"Error: Unable to read file.\n");
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return DMUS_E_DESCEND_CHUNK_FAIL;
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}
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}
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else
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{
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lpck->fccType = NULL;
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}
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// If this is the chunk we're looking for, stop looking
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if(((ckidFind == NULL) || (ckidFind == lpck->ckid)) &&
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((fccTypeFind == NULL) || (fccTypeFind == lpck->fccType)))
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{
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break;
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}
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// Ascend out of the chunk and try again
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HRESULT w = Ascend(lpck, 0);
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if(FAILED(w))
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{
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return w;
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}
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}
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return S_OK;
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}
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//////////////////////////////////////////////////////////////////////
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// CDirectMusicStream::Ascend
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STDMETHODIMP CDirectMusicStream::Ascend(LPMMCKINFO lpck, UINT /*wFlags*/)
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{
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assert(lpck);
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HRESULT hr;
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LARGE_INTEGER li;
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ULARGE_INTEGER uli;
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if (lpck->dwFlags & MMIO_DIRTY)
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{
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// <lpck> refers to a chunk created by CreateChunk();
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// check that the chunk size that was written when
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// CreateChunk() was called is the real chunk size;
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// if not, fix it
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LONG lOffset; // current offset in file
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LONG lActualSize; // actual size of chunk data
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li.QuadPart = 0;
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hr = m_pStream->Seek(li, STREAM_SEEK_CUR, &uli);
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if(FAILED(hr))
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{
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Trace(1,"Error: Unable to write file.\n");
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return DMUS_E_CANNOTSEEK;
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}
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else
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{
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lOffset = uli.LowPart;
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}
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if((lActualSize = lOffset - lpck->dwDataOffset) < 0)
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{
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Trace(1,"Error: Unable to write file.\n");
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return DMUS_E_CANNOTWRITE;
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}
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if(LOWORD(lActualSize) & 1)
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{
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ULONG cbWritten;
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// Chunk size is odd -- write a null pad byte
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hr = m_pStream->Write("\0", 1, &cbWritten);
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if(FAILED(hr) || cbWritten != 1)
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{
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Trace(1,"Error: Unable to write file.\n");
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return DMUS_E_CANNOTWRITE;
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}
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}
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if(lpck->cksize == (DWORD)lActualSize)
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{
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return S_OK;
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}
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// Fix the chunk header
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lpck->cksize = lActualSize;
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li.QuadPart = lpck->dwDataOffset - sizeof(DWORD);
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hr = m_pStream->Seek(li, STREAM_SEEK_SET, &uli);
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if(FAILED(hr))
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{
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Trace(1,"Error: Unable to write file.\n");
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return DMUS_E_CANNOTSEEK;
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}
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ULONG cbWritten;
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hr = m_pStream->Write(&lpck->cksize, sizeof(DWORD), &cbWritten);
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if(FAILED(hr) || cbWritten != sizeof(DWORD))
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{
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Trace(1,"Error: Unable to write file.\n");
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return DMUS_E_CANNOTWRITE;
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}
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}
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// Seek to the end of the chunk, past the null pad byte
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// (which is only there if chunk size is odd)
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li.QuadPart = lpck->dwDataOffset + lpck->cksize + (lpck->cksize & 1L);
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hr = m_pStream->Seek(li, STREAM_SEEK_SET, &uli);
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if(FAILED(hr))
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{
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Trace(1,"Error: Unable to write file.\n");
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return DMUS_E_CANNOTSEEK;
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}
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return S_OK;
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}
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//////////////////////////////////////////////////////////////////////
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// CDirectMusicStream::CreateChunk
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STDMETHODIMP CDirectMusicStream::CreateChunk(LPMMCKINFO lpck, UINT wFlags)
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{
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assert(lpck);
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UINT iBytes; // Bytes to write
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LONG lOffset; // Current offset in file
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// Store the offset of the data part of the chunk
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LARGE_INTEGER li;
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ULARGE_INTEGER uli;
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li.QuadPart = 0;
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HRESULT hr = m_pStream->Seek(li, STREAM_SEEK_CUR, &uli);
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if(FAILED(hr))
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{
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Trace(1,"Error: Unable to write file.\n");
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return DMUS_E_CANNOTSEEK;
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}
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else
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{
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lOffset = uli.LowPart;
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}
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lpck->dwDataOffset = lOffset + 2 * sizeof(DWORD);
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// figure out if a form/list type needs to be written
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if(wFlags & MMIO_CREATERIFF)
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{
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lpck->ckid = FOURCC_RIFF, iBytes = 3 * sizeof(DWORD);
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}
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else if(wFlags & MMIO_CREATELIST)
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{
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lpck->ckid = FOURCC_LIST, iBytes = 3 * sizeof(DWORD);
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}
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else
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{
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iBytes = 2 * sizeof(DWORD);
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}
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// Write the chunk header
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ULONG cbWritten;
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hr = m_pStream->Write(lpck, iBytes, &cbWritten);
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if(FAILED(hr) || cbWritten != iBytes)
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{
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Trace(1,"Error: Unable to write file.\n");
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return DMUS_E_CANNOTWRITE;
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}
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lpck->dwFlags = MMIO_DIRTY;
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return S_OK;
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}
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CRiffParser::CRiffParser(IStream *pStream)
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{
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assert(pStream);
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m_fDebugOn = FALSE;
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m_pStream = pStream;
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m_pParent = NULL;
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m_pChunk = NULL;
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m_lRead = 0;
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m_fFirstPass = TRUE;
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m_fComponentFailed = FALSE;
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m_fInComponent = FALSE;
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}
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void CRiffParser::EnterList(RIFFIO *pChunk)
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{
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assert (pChunk);
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pChunk->lRead = 0;
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pChunk->pParent = m_pChunk; // Previous chunk (could be NULL.)
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m_pParent = m_pChunk;
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m_pChunk = pChunk;
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m_fFirstPass = TRUE;
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}
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void CRiffParser::LeaveList()
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{
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assert (m_pChunk);
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if (m_pChunk)
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{
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m_pChunk = m_pChunk->pParent;
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if (m_pChunk)
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{
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m_pParent = m_pChunk->pParent;
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}
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}
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}
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BOOL CRiffParser::NextChunk(HRESULT * pHr)
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{
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BOOL fMore = FALSE;
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if (SUCCEEDED(*pHr))
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{
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// If this is the first time we've entered this list, there is no previous chunk.
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if (m_fFirstPass)
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{
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// Clear the flag.
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m_fFirstPass = FALSE;
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}
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else
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{
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// Clean up the previous pass.
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*pHr = LeaveChunk();
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}
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// Find out if there are more chunks to read.
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fMore = MoreChunks();
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// If so, and we don't have any failure, go ahead and read the next chunk header.
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if (fMore && SUCCEEDED(*pHr))
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{
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*pHr = EnterChunk();
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}
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}
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else
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{
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#ifdef DBG
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char szName[5];
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if (m_fDebugOn)
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{
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szName[4] = 0;
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strncpy(szName,(char *)&m_pChunk->ckid,4);
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Trace(0,"Error parsing %s, Read %ld of %ld\n",szName,m_pChunk->lRead,RIFF_ALIGN(m_pChunk->cksize));
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}
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#endif
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// If we were in a component, it's okay to fail. Mark that fact by setting
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// m_fComponentFailed then properly pull out of the chunk so we can
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// continue reading.
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if (m_fInComponent)
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{
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m_fComponentFailed = TRUE;
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// We don't need to check for first pass, because we must have gotten
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// that far. Instead, we just clean up from the failed chunk.
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// Note that this sets the hresult to S_OK, which is what we want.
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// Later, the caller needs to call ComponentFailed() to find out if
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// this error occured.
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*pHr = LeaveChunk();
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}
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else
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{
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// Clean up but leave the error code.
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LeaveChunk();
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}
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}
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return fMore && SUCCEEDED(*pHr);
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}
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BOOL CRiffParser::MoreChunks()
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{
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assert(m_pChunk);
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if (m_pChunk)
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{
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if (m_pParent)
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{
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// Return TRUE if there's enough room for another chunk.
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return (m_pParent->lRead < (m_pParent->cksize - 8));
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}
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else
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{
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// This must be a top level chunk, in which case there would only be one to read.
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return (m_pChunk->lRead == 0);
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}
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}
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// This should never happen unless CRiffParser is used incorrectly, in which
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// case the assert will help debug. But, in the interest of making Prefix happy...
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return false;
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}
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HRESULT CRiffParser::EnterChunk()
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{
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assert(m_pChunk);
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if (m_pChunk)
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{
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// Read the chunk header
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HRESULT hr = m_pStream->Read(m_pChunk, 2 * sizeof(DWORD), NULL);
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if (SUCCEEDED(hr))
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{
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#ifdef DBG
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char szName[5];
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if (m_fDebugOn)
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{
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szName[4] = 0;
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strncpy(szName,(char *)&m_pChunk->ckid,4);
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ULARGE_INTEGER ul;
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LARGE_INTEGER li;
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li.QuadPart = 0;
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m_pStream->Seek(li, STREAM_SEEK_CUR, &ul);
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Trace(0,"Entering %s, Length %ld, File position is %ld",szName,m_pChunk->cksize,(long)ul.QuadPart);
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}
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#endif
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// Clear bytes read field.
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m_pChunk->lRead = 0;
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// Check to see if this is a container (LIST or RIFF.)
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if((m_pChunk->ckid == FOURCC_RIFF) || (m_pChunk->ckid == FOURCC_LIST))
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{
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hr = m_pStream->Read(&m_pChunk->fccType, sizeof(DWORD), NULL);
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if (SUCCEEDED(hr))
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{
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m_pChunk->lRead += sizeof(DWORD);
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#ifdef DBG
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if (m_fDebugOn)
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{
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strncpy(szName,(char *)&m_pChunk->fccType,4);
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Trace(0," Type %s",szName);
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}
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#endif
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}
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else
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{
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Trace(1,"Error: Unable to read file.\n");
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}
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}
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#ifdef DBG
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if (m_fDebugOn) Trace(0,"\n");
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#endif
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}
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else
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{
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Trace(1,"Error: Unable to read file.\n");
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}
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return hr;
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}
|
|
// This should never happen unless CRiffParser is used incorrectly, in which
|
|
// case the assert will help debug. But, in the interest of making Prefix happy...
|
|
return E_FAIL;
|
|
}
|
|
|
|
HRESULT CRiffParser::LeaveChunk()
|
|
|
|
{
|
|
HRESULT hr = S_OK;
|
|
assert(m_pChunk);
|
|
if (m_pChunk)
|
|
{
|
|
m_fInComponent = false;
|
|
// Get the rounded up size of the chunk.
|
|
long lSize = RIFF_ALIGN(m_pChunk->cksize);
|
|
// Increment the parent's count of bytes read so far.
|
|
if (m_pParent)
|
|
{
|
|
m_pParent->lRead += lSize + (2 * sizeof(DWORD));
|
|
if (m_pParent->lRead > RIFF_ALIGN(m_pParent->cksize))
|
|
{
|
|
Trace(1,"Error: Unable to read file.\n");
|
|
hr = DMUS_E_DESCEND_CHUNK_FAIL; // Goofy error name, but need to be consistent with previous versions.
|
|
}
|
|
}
|
|
#ifdef DBG
|
|
char szName[5];
|
|
if (m_fDebugOn)
|
|
{
|
|
szName[4] = 0;
|
|
strncpy(szName,(char *)&m_pChunk->ckid,4);
|
|
ULARGE_INTEGER ul;
|
|
LARGE_INTEGER li;
|
|
li.QuadPart = 0;
|
|
m_pStream->Seek(li, STREAM_SEEK_CUR, &ul);
|
|
|
|
Trace(0,"Leaving %s, Read %ld of %ld, File Position is %ld\n",szName,m_pChunk->lRead,lSize,(long)ul.QuadPart);
|
|
}
|
|
#endif
|
|
// If we haven't actually read this entire chunk, seek to the end of it.
|
|
if (m_pChunk->lRead < lSize)
|
|
{
|
|
LARGE_INTEGER li;
|
|
li.QuadPart = lSize - m_pChunk->lRead;
|
|
hr = m_pStream->Seek(li,STREAM_SEEK_CUR,NULL);
|
|
// There's a chance it could fail because we are at the end of file with an odd length chunk.
|
|
if (FAILED(hr))
|
|
{
|
|
// If there's a parent, see if this is the last chunk.
|
|
if (m_pParent)
|
|
{
|
|
if (m_pParent->cksize >= (m_pParent->lRead - 1))
|
|
{
|
|
hr = S_OK;
|
|
}
|
|
}
|
|
// Else, see if we are an odd length.
|
|
else if (m_pChunk->cksize & 1)
|
|
{
|
|
hr = S_OK;
|
|
}
|
|
}
|
|
}
|
|
return hr;
|
|
}
|
|
// This should never happen unless CRiffParser is used incorrectly, in which
|
|
// case the assert will help debug. But, in the interest of making Prefix happy...
|
|
return E_FAIL;
|
|
}
|
|
|
|
HRESULT CRiffParser::Read(void *pv,ULONG cb)
|
|
|
|
{
|
|
assert(m_pChunk);
|
|
if (m_pChunk)
|
|
{
|
|
// Make sure we don't read beyond the end of the chunk.
|
|
if (((long)cb + m_pChunk->lRead) > m_pChunk->cksize)
|
|
{
|
|
cb -= (cb - (m_pChunk->cksize - m_pChunk->lRead));
|
|
}
|
|
HRESULT hr = m_pStream->Read(pv,cb,NULL);
|
|
if (SUCCEEDED(hr))
|
|
{
|
|
m_pChunk->lRead += cb;
|
|
}
|
|
else
|
|
{
|
|
Trace(1,"Error: Unable to read %ld bytes from file.\n",cb);
|
|
}
|
|
return hr;
|
|
}
|
|
// This should never happen unless CRiffParser is used incorrectly, in which
|
|
// case the assert will help debug. But, in the interest of making Prefix happy...
|
|
return E_FAIL;
|
|
}
|
|
|
|
HRESULT CRiffParser::Skip(ULONG ulBytes)
|
|
|
|
{
|
|
assert(m_pChunk);
|
|
if (m_pChunk)
|
|
{
|
|
// Make sure we don't scan beyond the end of the chunk.
|
|
if (((long)ulBytes + m_pChunk->lRead) > m_pChunk->cksize)
|
|
{
|
|
ulBytes -= (ulBytes - (m_pChunk->cksize - m_pChunk->lRead));
|
|
}
|
|
LARGE_INTEGER li;
|
|
li.HighPart = 0;
|
|
li.LowPart = ulBytes;
|
|
HRESULT hr = m_pStream->Seek( li, STREAM_SEEK_CUR, NULL );
|
|
if (SUCCEEDED(hr))
|
|
{
|
|
m_pChunk->lRead += ulBytes;
|
|
}
|
|
return hr;
|
|
}
|
|
// This should never happen unless CRiffParser is used incorrectly, in which
|
|
// case the assert will help debug. But, in the interest of making Prefix happy...
|
|
return E_FAIL;
|
|
}
|
|
|
|
|
|
void CRiffParser::MarkPosition()
|
|
|
|
{
|
|
assert(m_pChunk);
|
|
if (m_pChunk)
|
|
{
|
|
LARGE_INTEGER li;
|
|
ULARGE_INTEGER ul;
|
|
li.HighPart = 0;
|
|
li.LowPart = 0;
|
|
m_pStream->Seek(li, STREAM_SEEK_CUR, &ul);
|
|
m_pChunk->liPosition.QuadPart = (LONGLONG) ul.QuadPart;
|
|
}
|
|
}
|
|
|
|
HRESULT CRiffParser::SeekBack()
|
|
|
|
{
|
|
assert(m_pChunk);
|
|
if (m_pChunk)
|
|
{
|
|
// Move back to the start of the current chunk. Also, store the
|
|
// absolute position because that will be useful later when we need to seek to the
|
|
// end of this chunk.
|
|
ULARGE_INTEGER ul;
|
|
LARGE_INTEGER li;
|
|
li.QuadPart = 0;
|
|
li.QuadPart -= (m_pChunk->lRead + (2 * sizeof(DWORD)));
|
|
HRESULT hr = m_pStream->Seek(li, STREAM_SEEK_CUR, &ul);
|
|
// Now, save the absolute position for the end of this chunk.
|
|
m_pChunk->liPosition.QuadPart = ul.QuadPart +
|
|
RIFF_ALIGN(m_pChunk->cksize) + (2 * sizeof(DWORD));
|
|
m_pChunk->lRead = 0;
|
|
return hr;
|
|
}
|
|
return E_FAIL;
|
|
}
|
|
|
|
HRESULT CRiffParser::SeekForward()
|
|
|
|
{
|
|
assert(m_pChunk);
|
|
if (m_pChunk)
|
|
{
|
|
m_pChunk->lRead = RIFF_ALIGN(m_pChunk->cksize);
|
|
return m_pStream->Seek(m_pChunk->liPosition, STREAM_SEEK_SET, NULL);
|
|
}
|
|
return E_FAIL;
|
|
}
|