ScheduledTimer.h

#ifndef CARMA_UTIL_SCHEDULED_TIMER_H
#define CARMA_UTIL_SCHEDULED_TIMER_H

#include <ctime>

#include "carma/util/PthreadMutex.h"
#include "carma/util/PthreadCond.h"

namespace carma {
namespace util {


class ScheduledTimer {
    public:

        void WaitForNextFireTime( );

        void InterruptPresentOrNextWait( );

    protected:
        typedef struct ::timespec Timespec;

        static void sanityCheckTimespec( const Timespec & ts );

        explicit ScheduledTimer( bool preflight );

        virtual ~ScheduledTimer( );

        void SetNextFireTime( const Timespec & nextFireAbsTime );

        void SetNextFireTimeAndWait( const Timespec & nextFireAbsTime );

        void refreshNextFireAbsTimeIfNeeded( Timespec * nextFireAbsTime );

        virtual Timespec
        CalculateNextFireAbsoluteTime( const Timespec & fireAbsTime ) = 0;

    private:
        typedef enum {
            FIRE_ABS_TIME_STATE_INVALID,
            FIRE_ABS_TIME_STATE_NEXT,
            FIRE_ABS_TIME_STATE_LAST
        } FireAbsTimeState;

        FireAbsTimeState fireAbsTimeState_;
        Timespec         fireAbsTime_;
        PthreadCond      cond_;
        PthreadMutex     mutex_;
        bool             interruptRequested_;
};


}  // namespace util
}  // namespace carma

#endif