TimeKeeper.h

Go to the documentation of this file.

#ifndef WIRECELLUTIL_TIMEKEEPER
#define WIRECELLUTIL_TIMEKEEPER

#include <boost/date_time/posix_time/posix_time_types.hpp>
#include <vector>

namespace WireCell {

    /** A helper class to give some time keeping.
     *
     * Use like
     *
     *   TimeKeeper tk("starting");
     *   ...
     *   tk("starting long calculation....");
     *   do_long_calculation();
     *   tk("...done");
     *   ...
     *   info(tk.summary());
     */
    class TimeKeeper {
    public:
        typedef boost::posix_time::ptime ptime;
        typedef boost::posix_time::time_duration deltat;
        typedef std::pair<ptime, std::string> event;

        TimeKeeper(const std::string& msg = "start",
                   ptime starting_time = boost::posix_time::microsec_clock::local_time());
        ~TimeKeeper();

        /// Return the time at which this time keeper was started.
        ptime start_time() const;

        /// Return the time of the last event.
        ptime last_time() const;

        /// Return the duration between the last two events.
        deltat last_duration() const;

        /// Return the time duration between "now" and the start time.
        deltat since(ptime now = boost::posix_time::microsec_clock::local_time()) const;

        /// Record an event.
        std::string operator()(
            std::string msg = "<tick>",
            ptime now = boost::posix_time::microsec_clock::local_time());
        
        /// Return summary up to now.
        std::string summary() const;

        /// Return event by index.
        event operator[](int ind) const;


    private:
        /// Emit a formatted message for the given event index.
        std::string emit(int ind) const;


        std::vector< event > m_events;
    };
}
#endif