CPPUtil/UtilAbsTime.hpp

   1 //
   2 //  UtilAbsTime.hpp
   3 //  CPPUtil
   4 //
   5 //  Created by James McIlree on 4/14/13.
   6 //  Copyright (c) 2013 Apple. All rights reserved.
   7 //
   8
   9 #ifndef __CPPUtil__UtilAbsTime__
  10 #define __CPPUtil__UtilAbsTime__
  11
  12 class NanoTime;
  13
  14 class AbsTime {
  15     protected:
  16         uint64_t _time;
  17
  18     public:
  19         // Minimum and Maximum possible values
  20         static const AbsTime BEGINNING_OF_TIME;
  21         static const AbsTime END_OF_TIME;
  22
  23         static AbsTime now();
  24
  25         AbsTime() : _time(0ULL) {}
  26         explicit AbsTime(uint64_t t) : _time(t) {}
  27
  28         bool operator==(const AbsTime& rhs) const               { return this->_time == rhs._time; }
  29         bool operator!=(const AbsTime &rhs) const               { return !(*this == rhs); }
  30
  31         bool operator<(const AbsTime& rhs) const                { return this->_time < rhs._time; }
  32         bool operator<=(const AbsTime& rhs) const               { return this->_time <= rhs._time; }
  33         bool operator>(const AbsTime& rhs) const                { return this->_time > rhs._time; }
  34         bool operator>=(const AbsTime& rhs) const               { return this->_time >= rhs._time; }
  35
  36         // We do not want to be able to mutate AbsTime(s)
  37         // without type enforcement, but it is useful to be able
  38         // to say "if (time == 0) {}", so we have value based
  39         // operators for comparison
  40         bool operator==(uint64_t value) const                   { return this->_time == value; }
  41         bool operator!=(uint64_t value) const                   { return !(*this == value); }
  42
  43         bool operator<(uint64_t value) const                    { return this->_time < value; }
  44         bool operator<=(uint64_t value) const                   { return this->_time <= value; }
  45         bool operator>(uint64_t value) const                    { return this->_time > value; }
  46         bool operator>=(uint64_t value) const                   { return this->_time >= value; }
  47
  48         AbsTime operator+(const AbsTime& rhs) const             { return AbsTime(_time + rhs._time); }
  49         AbsTime operator-(const AbsTime& rhs) const             { return AbsTime(_time - rhs._time); }
  50         AbsTime operator*(const AbsTime& rhs) const             { return AbsTime(_time * rhs._time); }
  51         AbsTime operator/(const AbsTime& rhs) const             { return AbsTime(_time / rhs._time); }
  52
  53         AbsTime& operator+=(const AbsTime& rhs)                 { _time += rhs._time; return *this; }
  54
  55         NanoTime nano_time() const; // NOTE! Uses system mach_timebase_info, potentially expensive conversion costs.
  56         NanoTime nano_time(mach_timebase_info_data_t timebase_info) const;
  57
  58         uint64_t value() const                                  { return _time; }
  59         double double_value() const                             { return (double)_time; }
  60 };
  61
  62 #endif /* defined(__CPPUtil__UtilAbsTime__) */