Timer.h

/*
 * Copyright 2014 Saminda Abeyruwan (saminda@cs.miami.edu)
 *
 * Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 * Timer.h
 *
 *  Created on: Aug 5, 2013
 *      Author: sam
 */

#ifndef TIMER_H_
#define TIMER_H_

#ifdef WIN32
#include <windows.h>
#else
#include <sys/time.h>
#endif
#include <stdlib.h>

namespace RLLib
{
class Timer
{
  public:
    Timer()
    {
#ifdef WIN32
      QueryPerformanceFrequency(&frequency);
      startCount.QuadPart = 0;
      endCount.QuadPart = 0;
#else
      startCount.tv_sec = startCount.tv_usec = 0;
      endCount.tv_sec = endCount.tv_usec = 0;
#endif

      stopped = 0;
      startTimeInMicroSec = 0;
      endTimeInMicroSec = 0;
    }

    ~Timer()
    {
    }

    void start()
    {
      stopped = 0; // reset stop flag
#ifdef WIN32
          QueryPerformanceCounter(&startCount);
#else
      gettimeofday(&startCount, NULL);
#endif
    }

    void stop()
    {
      stopped = 1; // set timer stopped flag

#ifdef WIN32
      QueryPerformanceCounter(&endCount);
#else
      gettimeofday(&endCount, NULL);
#endif
    }

    double getElapsedTimeInMicroSec()
    {
#ifdef WIN32
      if(!stopped)
      QueryPerformanceCounter(&endCount);

      startTimeInMicroSec = startCount.QuadPart * (1000000.0 / frequency.QuadPart);
      endTimeInMicroSec = endCount.QuadPart * (1000000.0 / frequency.QuadPart);
#else
      if (!stopped)
        gettimeofday(&endCount, NULL);

      startTimeInMicroSec = (startCount.tv_sec * 1000000.0) + startCount.tv_usec;
      endTimeInMicroSec = (endCount.tv_sec * 1000000.0) + endCount.tv_usec;
#endif

      return endTimeInMicroSec - startTimeInMicroSec;
    }

    double getElapsedTimeInSec()
    {
      return this->getElapsedTimeInMicroSec() * 0.000001;
    }

    double getElapsedTime()
    {
      return this->getElapsedTimeInSec();
    }

    double getElapsedTimeInMilliSec()
    {
      return this->getElapsedTimeInMicroSec() * 0.001;
    }

  protected:

  private:
    double startTimeInMicroSec;
    double endTimeInMicroSec;
    int stopped;
#ifdef WIN32
    LARGE_INTEGER frequency;                    // ticks per second
    LARGE_INTEGER startCount;//
    LARGE_INTEGER endCount;//
#else
    timeval startCount;                         //
    timeval endCount;                           //
#endif
};

}  // namespace RLLib

#endif /* TIMER_H_ */