ringbuf.cpp
上传用户:zhongxx05
上传日期:2007-06-06
资源大小:33641k
文件大小:7k
- /* ***** BEGIN LICENSE BLOCK *****
- * Version: RCSL 1.0/RPSL 1.0
- *
- * Portions Copyright (c) 1995-2002 RealNetworks, Inc. All Rights Reserved.
- *
- * The contents of this file, and the files included with this file, are
- * subject to the current version of the RealNetworks Public Source License
- * Version 1.0 (the "RPSL") available at
- * http://www.helixcommunity.org/content/rpsl unless you have licensed
- * the file under the RealNetworks Community Source License Version 1.0
- * (the "RCSL") available at http://www.helixcommunity.org/content/rcsl,
- * in which case the RCSL will apply. You may also obtain the license terms
- * directly from RealNetworks. You may not use this file except in
- * compliance with the RPSL or, if you have a valid RCSL with RealNetworks
- * applicable to this file, the RCSL. Please see the applicable RPSL or
- * RCSL for the rights, obligations and limitations governing use of the
- * contents of the file.
- *
- * This file is part of the Helix DNA Technology. RealNetworks is the
- * developer of the Original Code and owns the copyrights in the portions
- * it created.
- *
- * This file, and the files included with this file, is distributed and made
- * available on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
- * EXPRESS OR IMPLIED, AND REALNETWORKS HEREBY DISCLAIMS ALL SUCH WARRANTIES,
- * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, FITNESS
- * FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
- *
- * Technology Compatibility Kit Test Suite(s) Location:
- * http://www.helixcommunity.org/content/tck
- *
- * Contributor(s):
- *
- * ***** END LICENSE BLOCK ***** */
- #include "hxtypes.h"
- #include "hxcom.h"
- #include "hlxclib/string.h"
- #include "hxcomm.h"
- #include "ihxpckts.h"
- #include "hxresult.h"
- #include "ringbuf.h"
- CIHXRingBuffer::CIHXRingBuffer(IHXCommonClassFactory *pClassFactory,
- UINT32 ulBufSize,
- UINT32 ulWrapSize)
- : m_lRefCount(0),
- m_pBuffer(NULL),
- m_pVBufBegin(NULL),
- m_ulBufBegin(0),
- m_ulBufEnd(0),
- m_ulWrite(0),
- m_ulRead(0),
- m_ulBytesWritten(0),
- m_ulBytesRead(0),
- m_ulBufSize(ulBufSize),
- m_ulGuardSize(ulWrapSize),
- m_pIhxBuffer(NULL),
- m_ulError(0)
- {
- // Create an IHXBuffer
- pClassFactory->CreateInstance(CLSID_IHXBuffer, (void**)&m_pIhxBuffer);
- if (m_pIhxBuffer)
- {
- // 32-byte allign buffer
- m_pIhxBuffer->SetSize(ulBufSize + ulWrapSize + 31);
- if (m_pIhxBuffer->GetSize() != ulBufSize + ulWrapSize + 31)
- {
- m_pIhxBuffer->Release();
- m_pIhxBuffer = NULL;
- m_ulError = HXR_OUTOFMEMORY;
-
- return;
- }
- m_pBuffer = m_pIhxBuffer->GetBuffer();
- m_pBuffer = (UCHAR*) (((PTR_INT) m_pBuffer + 31) & ~31);
-
- // Init members
- m_pBufBegin = m_pBuffer + m_ulGuardSize;
- m_ulBufEnd = m_ulBufBegin + m_ulBufSize;
- m_pVBufBegin = m_pBufBegin;
- m_pWrite =
- m_pRead = m_pBufBegin;
- }
- else
- {
- m_ulError = HXR_OUTOFMEMORY;
- }
- }
- CIHXRingBuffer::~CIHXRingBuffer()
- {
- // Release the buffer
- if (m_pIhxBuffer)
- m_pIhxBuffer->Release();
- }
- ///////////////////////////////////////////////////////////////////////////////
- // IUnknown methods
- ///////////////////////////////////////////////////////////////////////////////
- STDMETHODIMP CIHXRingBuffer::QueryInterface(REFIID riid,
- void** ppvObj)
- {
- if (IsEqualIID(riid, IID_IUnknown))
- {
- AddRef();
- *ppvObj = this;
- return HXR_OK;
- }
- else if (IsEqualIID(riid, IID_IHXBuffer))
- {
- AddRef();
- *ppvObj = (IHXBuffer*)this;
- return HXR_OK;
- }
- *ppvObj = NULL;
- return HXR_NOINTERFACE;
- }
- STDMETHODIMP_(ULONG32)
- CIHXRingBuffer::AddRef()
- {
- return InterlockedIncrement(&m_lRefCount);
- }
- STDMETHODIMP_(ULONG32)
- CIHXRingBuffer::Release()
- {
- return InterlockedIncrement(&m_lRefCount);
- }
-
- ///////////////////////////////////////////////////////////////////////////
- // IHXBuffer methods
- ///////////////////////////////////////////////////////////////////////////
- STDMETHODIMP
- CIHXRingBuffer::Get(REF(UCHAR*) pData,
- REF(ULONG32) ulLength)
- {
- return m_pIhxBuffer->Get(pData, ulLength);
- }
- STDMETHODIMP
- CIHXRingBuffer::Set(const UCHAR *pData,
- ULONG32 ulLength)
- {
- return m_pIhxBuffer->Set(pData, ulLength);
- }
- STDMETHODIMP
- CIHXRingBuffer::SetSize(ULONG32 ulLength)
- {
- return m_pIhxBuffer->SetSize(ulLength);
- }
- STDMETHODIMP_(ULONG32)
- CIHXRingBuffer::GetSize()
- {
- return m_pIhxBuffer->GetSize();
- }
- STDMETHODIMP_(UCHAR*)
- CIHXRingBuffer::GetBuffer()
- {
- return m_pIhxBuffer->GetBuffer();
- }
- void CIHXRingBuffer::Reset()
- {
- m_pVBufBegin = m_pBufBegin;
- m_pWrite =
- m_pRead = m_pBufBegin;
- m_ulBytesWritten =
- m_ulBytesRead = 0;
- }
- UINT32 CIHXRingBuffer::CopyData(UCHAR *pData, UINT32 ulBytes)
- {
- UINT32 ulCopy = min(ulBytes, GetFreeBufferSpace());
- UINT32 ulWrap = 0;
- // Handle buffer wrap
- if (m_ulWrite + ulCopy >= m_ulBufEnd)
- {
- ulWrap = m_ulBufEnd - m_ulWrite;
- memcpy(m_pWrite, pData, ulWrap); /* Flawfinder: ignore */
- pData += ulWrap;
- ulCopy -= ulWrap;
- m_ulBytesWritten += ulWrap;
- m_ulWrite = m_ulBufBegin;
- }
- memcpy(m_pWrite, pData, ulCopy); /* Flawfinder: ignore */
- m_ulBytesWritten += ulCopy;
- m_ulWrite += ulCopy;
- // Number of bytes copied to the buffer
- return ulCopy + ulWrap;
- }
- void CIHXRingBuffer::AdvanceRead(UINT32 ulBytes)
- {
- m_ulRead += ulBytes;
- if (m_ulRead >= m_ulBufEnd)
- m_ulRead -= m_ulBufSize;
- m_ulBytesRead += ulBytes;
- }
- void CIHXRingBuffer::DecrementRead(UINT32 ulBytes)
- {
- m_ulRead -= ulBytes;
- if (m_ulRead < m_ulBufBegin)
- m_ulRead += m_ulBufSize;
- m_ulBytesRead -= ulBytes;
- }
- UCHAR* CIHXRingBuffer::GetReadPointer(UINT32 &ulBytes)
- {
- ulBytes = m_ulBufEnd - m_ulRead;
- ulBytes = min((UINT32)ulBytes, GetBytesInBuffer());
- return m_pRead;
- }
- void CIHXRingBuffer::Wrap(UINT32 ulOldBytes)
- {
- // Ensures that distance from end of buffer
- // to read from is less that our guard.
- UINT32 ulSize = m_ulBufEnd - m_ulRead + ulOldBytes;
- if (ulSize <= m_ulGuardSize)
- {
- memcpy(m_pBufBegin-ulSize, m_pRead-ulOldBytes, ulSize); /* Flawfinder: ignore */
- m_pRead = m_pBufBegin-ulSize+ulOldBytes;
- m_pVBufBegin = m_pBufBegin-ulSize;
- }
- }