office-gobmx/canvas/source/tools/elapsedtime.cxx

/*************************************************************************
 *
 *  $RCSfile: elapsedtime.cxx,v $
 *
 *  $Revision: 1.3 $
 *
 *  last change: $Author: rt $ $Date: 2004-11-26 17:07:54 $
 *
 *  The Contents of this file are made available subject to the terms of
 *  either of the following licenses
 *
 *         - GNU Lesser General Public License Version 2.1
 *         - Sun Industry Standards Source License Version 1.1
 *
 *  Sun Microsystems Inc., October, 2000
 *
 *  GNU Lesser General Public License Version 2.1
 *  =============================================
 *  Copyright 2000 by Sun Microsystems, Inc.
 *  901 San Antonio Road, Palo Alto, CA 94303, USA
 *
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Lesser General Public
 *  License version 2.1, as published by the Free Software Foundation.
 *
 *  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
 *
 *
 *  Sun Industry Standards Source License Version 1.1
 *  =================================================
 *  The contents of this file are subject to the Sun Industry Standards
 *  Source License Version 1.1 (the "License"); You may not use this file
 *  except in compliance with the License. You may obtain a copy of the
 *  License at http://www.openoffice.org/license.html.
 *
 *  Software provided under this License is provided on an "AS IS" basis,
 *  WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING,
 *  WITHOUT LIMITATION, WARRANTIES THAT THE SOFTWARE IS FREE OF DEFECTS,
 *  MERCHANTABLE, FIT FOR A PARTICULAR PURPOSE, OR NON-INFRINGING.
 *  See the License for the specific provisions governing your rights and
 *  obligations concerning the Software.
 *
 *  The Initial Developer of the Original Code is: Sun Microsystems, Inc.
 *
 *  Copyright: 2000 by Sun Microsystems, Inc.
 *
 *  All Rights Reserved.
 *
 *  Contributor(s): _______________________________________
 *
 *
 ************************************************************************/

#ifndef _OSL_TIME_H_
#include <osl/time.h>
#endif

#include <canvas/elapsedtime.hxx>

#if defined(WIN) || defined(WNT)

// TEMP!!!
// Awaiting corresponding functionality in OSL
//
#define WIN32_LEAN_AND_MEAN
#include <windows.h>
#include <winbase.h>
#include <mmsystem.h>
#endif


namespace canvas
{
    namespace tools
    {
        namespace
        {
#if defined(WIN) || defined(WNT)
            static double fTimeFactor;
#endif

            double getTimeFactor()
            {
#if defined(WIN) || defined(WNT)
                // value is hardware-dependent
                return fTimeFactor;
#else
                // value is in nanoseconds
                return 10e-10;
#endif
            }

            sal_uInt64 getCurrentTime()
            {
#if defined(WIN) || defined(WNT)
                sal_uInt64 bRet( 0 );

                // TEMP!!!
                // Awaiting corresponding functionality in OSL
                //

                // is there a performance counter available?
                static bool bTimeSetupDone( false );
                static bool bPerfTimerAvailable;

                if( !bTimeSetupDone )
                {
                    LONGLONG nPerfCount;
                    if( QueryPerformanceFrequency((LARGE_INTEGER *) &nPerfCount) )
                    {
                        // yes, timer choice flag
                        bPerfTimerAvailable = true;

                        // set scaling factor
                        fTimeFactor = 1.0/nPerfCount;
                    }
                    else
                    {
                        // no performance counter, read in using timeGetTime
                        bPerfTimerAvailable = false;

                        // set timer scaling factor
                        fTimeFactor = 0.001;
                    }

                    bTimeSetupDone = true;
                }

                if( bPerfTimerAvailable )
                {
                    LONGLONG nCurrTime;

                    // read initial time
                    QueryPerformanceCounter((LARGE_INTEGER *) &nCurrTime);

                    bRet = nCurrTime;
                }
                else
                {
                    bRet = timeGetTime();
                }
#else
                TimeValue aTimeVal;
                sal_uInt64 bRet( 0 );

                if( osl_getSystemTime( &aTimeVal ) )
                {
                    // combine to seconds + fraction of second
                    bRet = ((sal_uInt64)aTimeVal.Seconds) * (sal_uInt64)1000000000 + (sal_uInt64)aTimeVal.Nanosec;
                }
#endif

                return bRet; // TODO(Q2): is 0 okay for the failure case here?
            }
        }

        ElapsedTime::ElapsedTime() :
            mnStartTime( getCurrentTime() ),
            mfTimeFactor( getTimeFactor() )
        {
        }

        void ElapsedTime::reset()
        {
            mnStartTime = getCurrentTime();
        }

        double ElapsedTime::getElapsedTime() const
        {
            sal_uInt64 nCurrTime( getCurrentTime() );

            return mfTimeFactor * (nCurrTime - mnStartTime);
        }

    }
}