_clock_gettimeofday.h

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/* === S T A R T =========================================================== */

#ifndef __ETL__CLOCK_GETTIMEOFDAY_H
#define __ETL__CLOCK_GETTIMEOFDAY_H

/* === H E A D E R S ======================================================= */

#include <sys/time.h>
#include <cmath>

/* === M A C R O S ========================================================= */

/* === T Y P E D E F S ===================================================== */

/* === C L A S S E S & S T R U C T S ======================================= */

_ETL_BEGIN_NAMESPACE

class clock_desc_gettimeofday
{
public:
    typedef double value_type;

    inline static bool realtime()
    { return true; }

    inline static bool proctime()
    { return false; }

    inline static value_type
    one_second()
    { return 1.0f; }

    inline static value_type precision()
    { return one_second()/(value_type)1000000.0f; }

    inline static const char *description()
    { return "UNIX gettimeofday()"; };

protected:
    class timestamp : public timeval
    {
        timestamp(int sec, int usec)
        { tv_sec=sec; tv_usec=usec; }

        friend class clock_desc_gettimeofday;
    public:
        timestamp() { }


        inline timestamp operator-(const timestamp &rhs)const
        {
            timestamp ret;
            ret.tv_usec=tv_usec-rhs.tv_usec;

            if(ret.tv_usec<0)
            {
                ret.tv_sec=tv_sec-rhs.tv_sec-1;
                ret.tv_usec+=1000000;
            }
            else
                ret.tv_sec=tv_sec-rhs.tv_sec;
            return ret;
        }

        inline timestamp operator+(timestamp rhs)const
        {
            rhs.tv_usec+=tv_usec;

            if(rhs.tv_usec>1000000)
            {
                rhs.tv_sec+=tv_sec+1;
                rhs.tv_usec-=1000000;
            }
            else
                rhs.tv_sec+=tv_sec;
            return rhs;
        }

        inline bool operator<(const timestamp &rhs)const
        { return tv_sec<rhs.tv_sec || tv_usec<rhs.tv_usec; }

        inline bool operator==(const timestamp &rhs)const
        { return tv_usec==rhs.tv_usec && tv_sec==rhs.tv_sec; }

        inline bool operator!=(const timestamp &rhs)const
        { return tv_usec!=rhs.tv_usec || tv_sec!=rhs.tv_sec; }
    };

    static void
    get_current_time(timestamp &x)
    { gettimeofday(&x,NULL);}

    static timestamp
    get_current_time()
    { timestamp ret; get_current_time(ret); return ret; }

    static value_type
    timestamp_to_seconds(const timestamp &x)
    { return (value_type)x.tv_sec + precision()*x.tv_usec; }

    static timestamp
    seconds_to_timestamp(const value_type &x)
    { return timestamp((int)floor(x), (int)((x-floor(x))/precision()+0.5)); }
};

_ETL_END_NAMESPACE

/* === E N D =============================================================== */

#endif