chrono
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// <chrono> -*- C++ -*-
// Copyright (C) 2008-2013 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library. This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 3, or (at your option)
// any later version.
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// Under Section 7 of GPL version 3, you are granted additional
// permissions described in the GCC Runtime Library Exception, version
// 3.1, as published by the Free Software Foundation.
// You should have received a copy of the GNU General Public License and
// a copy of the GCC Runtime Library Exception along with this program;
// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
// <http://www.gnu.org/licenses/>.
/** @file include/chrono
* This is a Standard C++ Library header.
*/
#ifndef _GLIBCXX_CHRONO
#define _GLIBCXX_CHRONO 1
#pragma GCC system_header
#if __cplusplus < 201103L
# include <bits/c++0x_warning.h>
#else
#include <ratio>
#include <type_traits>
#include <limits>
#include <ctime>
#ifdef _GLIBCXX_USE_C99_STDINT_TR1
namespace std _GLIBCXX_VISIBILITY(default)
{
/**
* @defgroup chrono Time
* @ingroup utilities
*
* Classes and functions for time.
* @{
*/
/** @namespace std::chrono
* @brief ISO C++ 2011 entities sub-namespace for time and date.
*/
namespace chrono
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
template<typename _Rep, typename _Period = ratio<1>>
struct duration;
template<typename _Clock, typename _Dur = typename _Clock::duration>
struct time_point;
_GLIBCXX_END_NAMESPACE_VERSION
}
_GLIBCXX_BEGIN_NAMESPACE_VERSION
// 20.11.4.3 specialization of common_type (for duration, sfinae-friendly)
template<typename _CT, typename _Period1, typename _Period2>
struct __duration_common_type_wrapper
{
private:
typedef __static_gcd<_Period1::num, _Period2::num> __gcd_num;
typedef __static_gcd<_Period1::den, _Period2::den> __gcd_den;
typedef typename _CT::type __cr;
typedef ratio<__gcd_num::value,
(_Period1::den / __gcd_den::value) * _Period2::den> __r;
public:
typedef __success_type<chrono::duration<__cr, __r>> type;
};
template<typename _Period1, typename _Period2>
struct __duration_common_type_wrapper<__failure_type, _Period1, _Period2>
{ typedef __failure_type type; };
template<typename _Rep1, typename _Period1, typename _Rep2, typename _Period2>
struct common_type<chrono::duration<_Rep1, _Period1>,
chrono::duration<_Rep2, _Period2>>
: public __duration_common_type_wrapper<typename __member_type_wrapper<
common_type<_Rep1, _Rep2>>::type, _Period1, _Period2>::type
{ };
// 20.11.4.3 specialization of common_type (for time_point, sfinae-friendly)
template<typename _CT, typename _Clock>
struct __timepoint_common_type_wrapper
{
typedef __success_type<chrono::time_point<_Clock, typename _CT::type>>
type;
};
template<typename _Clock>
struct __timepoint_common_type_wrapper<__failure_type, _Clock>
{ typedef __failure_type type; };
template<typename _Clock, typename _Duration1, typename _Duration2>
struct common_type<chrono::time_point<_Clock, _Duration1>,
chrono::time_point<_Clock, _Duration2>>
: public __timepoint_common_type_wrapper<typename __member_type_wrapper<
common_type<_Duration1, _Duration2>>::type, _Clock>::type
{ };
_GLIBCXX_END_NAMESPACE_VERSION
namespace chrono
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
// Primary template for duration_cast impl.
template<typename _ToDur, typename _CF, typename _CR,
bool _NumIsOne = false, bool _DenIsOne = false>
struct __duration_cast_impl
{
template<typename _Rep, typename _Period>
static constexpr _ToDur
__cast(const duration<_Rep, _Period>& __d)
{
typedef typename _ToDur::rep __to_rep;
return _ToDur(static_cast<__to_rep>(static_cast<_CR>(__d.count())
* static_cast<_CR>(_CF::num)
/ static_cast<_CR>(_CF::den)));
}
};
template<typename _ToDur, typename _CF, typename _CR>
struct __duration_cast_impl<_ToDur, _CF, _CR, true, true>
{
template<typename _Rep, typename _Period>
static constexpr _ToDur
__cast(const duration<_Rep, _Period>& __d)
{
typedef typename _ToDur::rep __to_rep;
return _ToDur(static_cast<__to_rep>(__d.count()));
}
};
template<typename _ToDur, typename _CF, typename _CR>
struct __duration_cast_impl<_ToDur, _CF, _CR, true, false>
{
template<typename _Rep, typename _Period>
static constexpr _ToDur
__cast(const duration<_Rep, _Period>& __d)
{
typedef typename _ToDur::rep __to_rep;
return _ToDur(static_cast<__to_rep>(
static_cast<_CR>(__d.count()) / static_cast<_CR>(_CF::den)));
}
};
template<typename _ToDur, typename _CF, typename _CR>
struct __duration_cast_impl<_ToDur, _CF, _CR, false, true>
{
template<typename _Rep, typename _Period>
static constexpr _ToDur
__cast(const duration<_Rep, _Period>& __d)
{
typedef typename _ToDur::rep __to_rep;
return _ToDur(static_cast<__to_rep>(
static_cast<_CR>(__d.count()) * static_cast<_CR>(_CF::num)));
}
};
template<typename _Tp>
struct __is_duration
: std::false_type
{ };
template<typename _Rep, typename _Period>
struct __is_duration<duration<_Rep, _Period>>
: std::true_type
{ };
/// duration_cast
template<typename _ToDur, typename _Rep, typename _Period>
constexpr typename enable_if<__is_duration<_ToDur>::value,
_ToDur>::type
duration_cast(const duration<_Rep, _Period>& __d)
{
typedef typename _ToDur::period __to_period;
typedef typename _ToDur::rep __to_rep;
typedef ratio_divide<_Period, __to_period> __cf;
typedef typename common_type<__to_rep, _Rep, intmax_t>::type
__cr;
typedef __duration_cast_impl<_ToDur, __cf, __cr,
__cf::num == 1, __cf::den == 1> __dc;
return __dc::__cast(__d);
}
/// treat_as_floating_point
template<typename _Rep>
struct treat_as_floating_point
: is_floating_point<_Rep>
{ };
/// duration_values
template<typename _Rep>
struct duration_values
{
static constexpr _Rep
zero()
{ return _Rep(0); }
static constexpr _Rep
max()
{ return numeric_limits<_Rep>::max(); }
static constexpr _Rep
min()
{ return numeric_limits<_Rep>::lowest(); }
};
template<typename T>
struct __is_ratio
: std::false_type
{ };
template<intmax_t _Num, intmax_t _Den>
struct __is_ratio<ratio<_Num, _Den>>
: std::true_type
{ };
/// duration
template<typename _Rep, typename _Period>
struct duration
{
typedef _Rep rep;
typedef _Period period;
static_assert(!__is_duration<_Rep>::value, "rep cannot be a duration");
static_assert(__is_ratio<_Period>::value,
"period must be a specialization of ratio");
static_assert(_Period::num > 0, "period must be positive");
// 20.11.5.1 construction / copy / destroy
constexpr duration() = default;
// NB: Make constexpr implicit. This cannot be explicitly
// constexpr, as any UDT that is not a literal type with a
// constexpr copy constructor will be ill-formed.
duration(const duration&) = default;
template<typename _Rep2, typename = typename
enable_if<is_convertible<_Rep2, rep>::value
&& (treat_as_floating_point<rep>::value
|| !treat_as_floating_point<_Rep2>::value)>::type>
constexpr explicit duration(const _Rep2& __rep)
: __r(static_cast<rep>(__rep)) { }
template<typename _Rep2, typename _Period2, typename = typename
enable_if<treat_as_floating_point<rep>::value
|| (ratio_divide<_Period2, period>::den == 1
&& !treat_as_floating_point<_Rep2>::value)>::type>
constexpr duration(const duration<_Rep2, _Period2>& __d)
: __r(duration_cast<duration>(__d).count()) { }
~duration() = default;
duration& operator=(const duration&) = default;
// 20.11.5.2 observer
constexpr rep
count() const
{ return __r; }
// 20.11.5.3 arithmetic
constexpr duration
operator+() const
{ return *this; }
constexpr duration
operator-() const
{ return duration(-__r); }
duration&
operator++()
{
++__r;
return *this;
}
duration
operator++(int)
{ return duration(__r++); }
duration&
operator--()
{
--__r;
return *this;
}
duration
operator--(int)
{ return duration(__r--); }
duration&
operator+=(const duration& __d)
{
__r += __d.count();
return *this;
}
duration&
operator-=(const duration& __d)
{
__r -= __d.count();
return *this;
}
duration&
operator*=(const rep& __rhs)
{
__r *= __rhs;
return *this;
}
duration&
operator/=(const rep& __rhs)
{
__r /= __rhs;
return *this;
}
// DR 934.
template<typename _Rep2 = rep>
typename enable_if<!treat_as_floating_point<_Rep2>::value,
duration&>::type
operator%=(const rep& __rhs)
{
__r %= __rhs;
return *this;
}
template<typename _Rep2 = rep>
typename enable_if<!treat_as_floating_point<_Rep2>::value,
duration&>::type
operator%=(const duration& __d)
{
__r %= __d.count();
return *this;
}
// 20.11.5.4 special values
static constexpr duration
zero()
{ return duration(duration_values<rep>::zero()); }
static constexpr duration
min()
{ return duration(duration_values<rep>::min()); }
static constexpr duration
max()
{ return duration(duration_values<rep>::max()); }
private:
rep __r;
};
template<typename _Rep1, typename _Period1,
typename _Rep2, typename _Period2>
constexpr typename common_type<duration<_Rep1, _Period1>,
duration<_Rep2, _Period2>>::type
operator+(const duration<_Rep1, _Period1>& __lhs,
const duration<_Rep2, _Period2>& __rhs)
{
typedef duration<_Rep1, _Period1> __dur1;
typedef duration<_Rep2, _Period2> __dur2;
typedef typename common_type<__dur1,__dur2>::type __cd;
return __cd(__cd(__lhs).count() + __cd(__rhs).count());
}
template<typename _Rep1, typename _Period1,
typename _Rep2, typename _Period2>
constexpr typename common_type<duration<_Rep1, _Period1>,
duration<_Rep2, _Period2>>::type
operator-(const duration<_Rep1, _Period1>& __lhs,
const duration<_Rep2, _Period2>& __rhs)
{
typedef duration<_Rep1, _Period1> __dur1;
typedef duration<_Rep2, _Period2> __dur2;
typedef typename common_type<__dur1,__dur2>::type __cd;
return __cd(__cd(__lhs).count() - __cd(__rhs).count());
}
template<typename _Rep1, typename _Rep2, bool =
is_convertible<_Rep2,
typename common_type<_Rep1, _Rep2>::type>::value>
struct __common_rep_type { };
template<typename _Rep1, typename _Rep2>
struct __common_rep_type<_Rep1, _Rep2, true>
{ typedef typename common_type<_Rep1, _Rep2>::type type; };
template<typename _Rep1, typename _Period, typename _Rep2>
constexpr
duration<typename __common_rep_type<_Rep1, _Rep2>::type, _Period>
operator*(const duration<_Rep1, _Period>& __d, const _Rep2& __s)
{
typedef duration<typename common_type<_Rep1, _Rep2>::type, _Period>
__cd;
return __cd(__cd(__d).count() * __s);
}
template<typename _Rep1, typename _Rep2, typename _Period>
constexpr
duration<typename __common_rep_type<_Rep2, _Rep1>::type, _Period>
operator*(const _Rep1& __s, const duration<_Rep2, _Period>& __d)
{ return __d * __s; }
template<typename _Rep1, typename _Period, typename _Rep2>
constexpr duration<typename __common_rep_type<_Rep1, typename
enable_if<!__is_duration<_Rep2>::value, _Rep2>::type>::type, _Period>
operator/(const duration<_Rep1, _Period>& __d, const _Rep2& __s)
{
typedef duration<typename common_type<_Rep1, _Rep2>::type, _Period>
__cd;
return __cd(__cd(__d).count() / __s);
}
template<typename _Rep1, typename _Period1,
typename _Rep2, typename _Period2>
constexpr typename common_type<_Rep1, _Rep2>::type
operator/(const duration<_Rep1, _Period1>& __lhs,
const duration<_Rep2, _Period2>& __rhs)
{
typedef duration<_Rep1, _Period1> __dur1;
typedef duration<_Rep2, _Period2> __dur2;
typedef typename common_type<__dur1,__dur2>::type __cd;
return __cd(__lhs).count() / __cd(__rhs).count();
}
// DR 934.
template<typename _Rep1, typename _Period, typename _Rep2>
constexpr duration<typename __common_rep_type<_Rep1, typename
enable_if<!__is_duration<_Rep2>::value, _Rep2>::type>::type, _Period>
operator%(const duration<_Rep1, _Period>& __d, const _Rep2& __s)
{
typedef duration<typename common_type<_Rep1, _Rep2>::type, _Period>
__cd;
return __cd(__cd(__d).count() % __s);
}
template<typename _Rep1, typename _Period1,
typename _Rep2, typename _Period2>
constexpr typename common_type<duration<_Rep1, _Period1>,
duration<_Rep2, _Period2>>::type
operator%(const duration<_Rep1, _Period1>& __lhs,
const duration<_Rep2, _Period2>& __rhs)
{
typedef duration<_Rep1, _Period1> __dur1;
typedef duration<_Rep2, _Period2> __dur2;
typedef typename common_type<__dur1,__dur2>::type __cd;
return __cd(__cd(__lhs).count() % __cd(__rhs).count());
}
// comparisons
template<typename _Rep1, typename _Period1,
typename _Rep2, typename _Period2>
constexpr bool
operator==(const duration<_Rep1, _Period1>& __lhs,
const duration<_Rep2, _Period2>& __rhs)
{
typedef duration<_Rep1, _Period1> __dur1;
typedef duration<_Rep2, _Period2> __dur2;
typedef typename common_type<__dur1,__dur2>::type __ct;
return __ct(__lhs).count() == __ct(__rhs).count();
}
template<typename _Rep1, typename _Period1,
typename _Rep2, typename _Period2>
constexpr bool
operator<(const duration<_Rep1, _Period1>& __lhs,
const duration<_Rep2, _Period2>& __rhs)
{
typedef duration<_Rep1, _Period1> __dur1;
typedef duration<_Rep2, _Period2> __dur2;
typedef typename common_type<__dur1,__dur2>::type __ct;
return __ct(__lhs).count() < __ct(__rhs).count();
}
template<typename _Rep1, typename _Period1,
typename _Rep2, typename _Period2>
constexpr bool
operator!=(const duration<_Rep1, _Period1>& __lhs,
const duration<_Rep2, _Period2>& __rhs)
{ return !(__lhs == __rhs); }
template<typename _Rep1, typename _Period1,
typename _Rep2, typename _Period2>
constexpr bool
operator<=(const duration<_Rep1, _Period1>& __lhs,
const duration<_Rep2, _Period2>& __rhs)
{ return !(__rhs < __lhs); }
template<typename _Rep1, typename _Period1,
typename _Rep2, typename _Period2>
constexpr bool
operator>(const duration<_Rep1, _Period1>& __lhs,
const duration<_Rep2, _Period2>& __rhs)
{ return __rhs < __lhs; }
template<typename _Rep1, typename _Period1,
typename _Rep2, typename _Period2>
constexpr bool
operator>=(const duration<_Rep1, _Period1>& __lhs,
const duration<_Rep2, _Period2>& __rhs)
{ return !(__lhs < __rhs); }
/// nanoseconds
typedef duration<int64_t, nano> nanoseconds;
/// microseconds
typedef duration<int64_t, micro> microseconds;
/// milliseconds
typedef duration<int64_t, milli> milliseconds;
/// seconds
typedef duration<int64_t> seconds;
/// minutes
typedef duration<int, ratio< 60>> minutes;
/// hours
typedef duration<int, ratio<3600>> hours;
/// time_point
template<typename _Clock, typename _Dur>
struct time_point
{
typedef _Clock clock;
typedef _Dur duration;
typedef typename duration::rep rep;
typedef typename duration::period period;
constexpr time_point() : __d(duration::zero())
{ }
constexpr explicit time_point(const duration& __dur)
: __d(__dur)
{ }
// conversions
template<typename _Dur2>
constexpr time_point(const time_point<clock, _Dur2>& __t)
: __d(__t.time_since_epoch())
{ }
// observer
constexpr duration
time_since_epoch() const
{ return __d; }
// arithmetic
time_point&
operator+=(const duration& __dur)
{
__d += __dur;
return *this;
}
time_point&
operator-=(const duration& __dur)
{
__d -= __dur;
return *this;
}
// special values
static constexpr time_point
min()
{ return time_point(duration::min()); }
static constexpr time_point
max()
{ return time_point(duration::max()); }
private:
duration __d;
};
/// time_point_cast
template<typename _ToDur, typename _Clock, typename _Dur>
constexpr typename enable_if<__is_duration<_ToDur>::value,
time_point<_Clock, _ToDur>>::type
time_point_cast(const time_point<_Clock, _Dur>& __t)
{
typedef time_point<_Clock, _ToDur> __time_point;
return __time_point(duration_cast<_ToDur>(__t.time_since_epoch()));
}
template<typename _Clock, typename _Dur1,
typename _Rep2, typename _Period2>
constexpr time_point<_Clock,
typename common_type<_Dur1, duration<_Rep2, _Period2>>::type>
operator+(const time_point<_Clock, _Dur1>& __lhs,
const duration<_Rep2, _Period2>& __rhs)
{
typedef duration<_Rep2, _Period2> __dur2;
typedef typename common_type<_Dur1,__dur2>::type __ct;
typedef time_point<_Clock, __ct> __time_point;
return __time_point(__lhs.time_since_epoch() + __rhs);
}
template<typename _Rep1, typename _Period1,
typename _Clock, typename _Dur2>
constexpr time_point<_Clock,
typename common_type<duration<_Rep1, _Period1>, _Dur2>::type>
operator+(const duration<_Rep1, _Period1>& __lhs,
const time_point<_Clock, _Dur2>& __rhs)
{
typedef duration<_Rep1, _Period1> __dur1;
typedef typename common_type<__dur1,_Dur2>::type __ct;
typedef time_point<_Clock, __ct> __time_point;
return __time_point(__rhs.time_since_epoch() + __lhs);
}
template<typename _Clock, typename _Dur1,
typename _Rep2, typename _Period2>
constexpr time_point<_Clock,
typename common_type<_Dur1, duration<_Rep2, _Period2>>::type>
operator-(const time_point<_Clock, _Dur1>& __lhs,
const duration<_Rep2, _Period2>& __rhs)
{
typedef duration<_Rep2, _Period2> __dur2;
typedef typename common_type<_Dur1,__dur2>::type __ct;
typedef time_point<_Clock, __ct> __time_point;
return __time_point(__lhs.time_since_epoch() -__rhs);
}
template<typename _Clock, typename _Dur1, typename _Dur2>
constexpr typename common_type<_Dur1, _Dur2>::type
operator-(const time_point<_Clock, _Dur1>& __lhs,
const time_point<_Clock, _Dur2>& __rhs)
{ return __lhs.time_since_epoch() - __rhs.time_since_epoch(); }
template<typename _Clock, typename _Dur1, typename _Dur2>
constexpr bool
operator==(const time_point<_Clock, _Dur1>& __lhs,
const time_point<_Clock, _Dur2>& __rhs)
{ return __lhs.time_since_epoch() == __rhs.time_since_epoch(); }
template<typename _Clock, typename _Dur1, typename _Dur2>
constexpr bool
operator!=(const time_point<_Clock, _Dur1>& __lhs,
const time_point<_Clock, _Dur2>& __rhs)
{ return !(__lhs == __rhs); }
template<typename _Clock, typename _Dur1, typename _Dur2>
constexpr bool
operator<(const time_point<_Clock, _Dur1>& __lhs,
const time_point<_Clock, _Dur2>& __rhs)
{ return __lhs.time_since_epoch() < __rhs.time_since_epoch(); }
template<typename _Clock, typename _Dur1, typename _Dur2>
constexpr bool
operator<=(const time_point<_Clock, _Dur1>& __lhs,
const time_point<_Clock, _Dur2>& __rhs)
{ return !(__rhs < __lhs); }
template<typename _Clock, typename _Dur1, typename _Dur2>
constexpr bool
operator>(const time_point<_Clock, _Dur1>& __lhs,
const time_point<_Clock, _Dur2>& __rhs)
{ return __rhs < __lhs; }
template<typename _Clock, typename _Dur1, typename _Dur2>
constexpr bool
operator>=(const time_point<_Clock, _Dur1>& __lhs,
const time_point<_Clock, _Dur2>& __rhs)
{ return !(__lhs < __rhs); }
/// system_clock
struct system_clock
{
#ifdef _GLIBCXX_USE_CLOCK_REALTIME
typedef chrono::nanoseconds duration;
#elif defined(_GLIBCXX_USE_GETTIMEOFDAY)
typedef chrono::microseconds duration;
#else
typedef chrono::seconds duration;
#endif
typedef duration::rep rep;
typedef duration::period period;
typedef chrono::time_point<system_clock, duration> time_point;
static_assert(system_clock::duration::min()
< system_clock::duration::zero(),
"a clock's minimum duration cannot be less than its epoch");
static constexpr bool is_steady = false;
static time_point
now() noexcept;
// Map to C API
static std::time_t
to_time_t(const time_point& __t) noexcept
{
return std::time_t(duration_cast<chrono::seconds>
(__t.time_since_epoch()).count());
}
static time_point
from_time_t(std::time_t __t) noexcept
{
typedef chrono::time_point<system_clock, seconds> __from;
return time_point_cast<system_clock::duration>
(__from(chrono::seconds(__t)));
}
};
#ifdef _GLIBCXX_USE_CLOCK_MONOTONIC
/// steady_clock
struct steady_clock
{
typedef chrono::nanoseconds duration;
typedef duration::rep rep;
typedef duration::period period;
typedef chrono::time_point<steady_clock, duration> time_point;
static constexpr bool is_steady = true;
static time_point
now() noexcept;
};
#else
typedef system_clock steady_clock;
#endif
typedef system_clock high_resolution_clock;
_GLIBCXX_END_NAMESPACE_VERSION
} // namespace chrono
// @} group chrono
} // namespace
#endif //_GLIBCXX_USE_C99_STDINT_TR1
#endif // C++11
#endif //_GLIBCXX_CHRONO