pxcallbk.h

linux下的一款播放器

/* ***** BEGIN LICENSE BLOCK *****
 * Source last modified: $Id: pxcallbk.h,v 1.1.26.1 2004/07/09 01:54:36 hubbe Exp $
 * 
 * Portions Copyright (c) 1995-2004 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 (the "RPSL") available at
 * http://www.helixcommunity.org/content/rpsl unless you have licensed
 * the file under the current version of the RealNetworks Community
 * Source License (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
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 * 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.
 * 
 * Alternatively, the contents of this file may be used under the
 * terms of the GNU General Public License Version 2 or later (the
 * "GPL") in which case the provisions of the GPL are applicable
 * instead of those above. If you wish to allow use of your version of
 * this file only under the terms of the GPL, and not to allow others
 * to use your version of this file under the terms of either the RPSL
 * or RCSL, indicate your decision by deleting the provisions above
 * and replace them with the notice and other provisions required by
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 * use your version of this file under the terms of any one of the
 * RPSL, the RCSL or the GPL.
 * 
 * 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
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 * ENJOYMENT OR NON-INFRINGEMENT.
 * 
 * Technology Compatibility Kit Test Suite(s) Location:
 *    http://www.helixcommunity.org/content/tck
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 * Contributor(s):
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 * ***** END LICENSE BLOCK ***** */

#ifndef PXCALLBK_H
#define PXCALLBK_H

// Forward declarations
typedef _INTERFACE IHXCallback  IHXCallback;
typedef struct _HXTimeval       HXTimeval;
typedef _INTERFACE IHXScheduler IHXScheduler;

class PXCallbackResponse : public IUnknown
{
public:
    // IUnknown methods
    STDMETHOD(QueryInterface)   (THIS_ REFIID riid, void **ppvObj) PURE;
    STDMETHOD_(ULONG32,AddRef)  (THIS) PURE;
    STDMETHOD_(ULONG32,Release) (THIS) PURE;

    // PXCallbackResponse methods
    STDMETHOD(HandleCallback)   (THIS_ UINT32 ulSchedulerTime,
                                       UINT32 ulInstance) PURE;
};

class PXCallback : public IHXCallback
{
public:
    PXCallback(UINT32 ulInstance = 0);
    virtual ~PXCallback();

    // IUnknown methods
    STDMETHOD(QueryInterface)   (THIS_ REFIID riid, void **ppvObj);
    STDMETHOD_(ULONG32,AddRef)  (THIS);
    STDMETHOD_(ULONG32,Release) (THIS);

    // IHXCallback methods
    STDMETHOD(Func)             (THIS);

    // PXCallback methods
    HX_RESULT  Init(IUnknown* pContext, PXCallbackResponse* pResponse,
                    BOOL bReportSchedulerTime = TRUE, UINT32 ulCurrentTime = 0);
    HX_RESULT  ScheduleRelativeCallback(UINT32 ulTimeFromNow);
    HX_RESULT  ScheduleAbsoluteCallback(HXTimeval cTime);
    HXTimeval GetCurrentSchedulerTime();
    BOOL       IsCallbackPending();
    void       RemovePendingCallback();
protected:
    INT32               m_lRefCount;
    IHXScheduler*      m_pScheduler;
    PXCallbackResponse* m_pResponse;
    UINT32              m_ulCallbackHandle;
    BOOL                m_bCallbackPending;
    BOOL                m_bReportSchedulerTime;
    UINT32              m_ulTimeDelta;
    UINT32              m_ulInstance;

    void                Deallocate();
};

inline HXTimeval PXCallback::GetCurrentSchedulerTime()
{
    HXTimeval cRet;
    cRet.tv_sec  = 0;
    cRet.tv_usec = 0;

    if (m_pScheduler)
    {
        cRet = m_pScheduler->GetCurrentSchedulerTime();
    }

    return cRet;
}

inline BOOL PXCallback::IsCallbackPending()
{
    return m_bCallbackPending;
}

inline void PXCallback::RemovePendingCallback()
{
    if (m_bCallbackPending && m_pScheduler)
    {
        m_pScheduler->Remove(m_ulCallbackHandle);
        m_bCallbackPending = FALSE;
        m_ulCallbackHandle = 0;
    }
}

#endif