4040 lines
164 KiB
HTML
4040 lines
164 KiB
HTML
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
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<html><head>
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<meta http-equiv="content-type" content="text/html; charset=ISO-8859-1">
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<title>time2_demo</title>
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</head><body>
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<pre><font color="#c80000">/*
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Copyright (c) 2008 Howard Hinnant
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Distributed under the Boost Software License, Version 1.0. (See accompanying
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file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
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A prototype of a proposal for a time/duration/clock library for the C++ standard.
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It is intended that this be a solid foundation upon which higher level libraries
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can be based. Examples of such libraries include a date/time library and a
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physical quantities library.
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Two general purpose facilities are proposed:
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common_type
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ratio
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And 5 time/duration/clock facilities are proposed
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duration
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time_point
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system_clock
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monotonic_clock <font color="#c80000">// optional</font>
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high_resolution_clock <font color="#c80000">// optional</font>
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Much thanks to Andrei Alexandrescu,
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Walter Brown,
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Peter Dimov,
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Jeff Garland,
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Terry Golubiewski,
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Daniel Krügler,
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Anthony Williams.
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Synopsis
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namespace std
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{
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<font color="#c80000">// <type_traits></font>
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<font color="#c80000">// common_type</font>
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<font color="#c80000">// common_type is ageneral purpose trait that can be specialized for user-defined types.</font>
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<font color="#c80000">// The semantics are intended to be identical to finding the resulting type of a</font>
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<font color="#c80000">// the conditional operator.</font>
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<font color="#c80000">// The client may need to specialize common_type if he wishes to convert to or from</font>
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<font color="#c80000">// another type only explicitly. It is used to determine the result type</font>
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<font color="#c80000">// in "mixed-mode" duration and time_point arithmetic. It will also find use in</font>
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<font color="#c80000">// similar "mixed-mode" arithmetic applications.</font>
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template <class T, class U>
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struct common_type
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{
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private:
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static T t();
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static U u();
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public:
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typedef decltype(true ? t() : u()) type;
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};
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<font color="#c80000">// or...</font>
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template <class ...T> struct common_type;
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template <class T>
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struct common_type<T>
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{
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typedef T type;
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};
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template <class T, class U>
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struct common_type<T, U>
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{
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private:
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static T t();
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static U u();
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public:
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typedef decltype(true ? t() : u()) type;
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};
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template <class T, class U, class ...V>
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struct common_type<T, U, V...>
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{
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typedef typename common_type<typename common_type<T, U>::type, V...>::type type;
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};
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<font color="#c80000">// This alternative variadic formulation of common_type has some advantages:</font>
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<font color="#c80000">//</font>
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<font color="#c80000">// 1. The obvious advantage is that it can handle 3 or more arguments seamlessly.</font>
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<font color="#c80000">// This can come in handy when writing template functions that take more than</font>
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<font color="#c80000">// two arguments, such as fma(x, y, z).</font>
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<font color="#c80000">//</font>
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<font color="#c80000">// 2. We could just get rid of identity (avoiding the legacy conflict) and use</font>
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<font color="#c80000">// common_type<T>::type in the one place we use identity<T>::type today.</font>
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<font color="#c80000">//</font>
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<font color="#c80000">// 3. For clients that need to specialize common_type (such as duration and time_point),</font>
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<font color="#c80000">// the client still needs to specialize only the two-argument version. The default</font>
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<font color="#c80000">// definition of the higher-order common_type will automatically use the client's</font>
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<font color="#c80000">// specialized two-argument version.</font>
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<font color="#c80000">// For example:</font>
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<font color="#c80000">// common_type<duration<double>, hours, microseconds>::type is duration<double, micro></font>
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<font color="#c80000">// ... end or</font>
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<font color="#c80000">// The cost of not including either version of common_type is that it is very likely that</font>
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<font color="#c80000">// the implementation would include it anyway, but spell it __common_type instead. This</font>
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<font color="#c80000">// would prevent authors of arithmetic emulators from using their classes as representations</font>
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<font color="#c80000">// with durations unless the emulator had exactly one implicit conversion to or from an</font>
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<font color="#c80000">// arithmetic type. This would be a large loss of functionality from the client's point</font>
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<font color="#c80000">// of view, possibly mandating a less safe interface for the client's arithmetic emulator.</font>
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<font color="#c80000">// ratio</font>
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<font color="#c80000">// ratio is a general purpose type allowing one to easily and safely compute integral</font>
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<font color="#c80000">// ratio values at compile time. The ratio class catches all errors (such as divide by</font>
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<font color="#c80000">// zero and overflow) at compile time. It is used in the duration and time_point libraries</font>
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<font color="#c80000">// to efficiently create units of time. It can also be used in other "quantity"</font>
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<font color="#c80000">// libraries (both std-defined and user-defined), or anywhere there is an integral</font>
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<font color="#c80000">// ratio which is known at compile time. The use of this utility can greatly reduce</font>
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<font color="#c80000">// the chances of run time overflow because the ratio (and any ratios resulting from</font>
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<font color="#c80000">// ratio arithmetic) are always reduced to lowest terms.</font>
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<font color="#c80000">// The cost of not including ratio would mean that the implementor would likely have this</font>
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<font color="#c80000">// functionality anyway, but spell it __ratio instead. This would prevent the client from</font>
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<font color="#c80000">// using ratio in his own code as demonstrated in the "User1" example. Furthermore duration</font>
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<font color="#c80000">// would have to be templated on two long long's instead of on ratio like so:</font>
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<font color="#c80000">//</font>
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<font color="#c80000">// template <class Rep, long long N, long long D> duration.</font>
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<font color="#c80000">//</font>
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<font color="#c80000">// This would mean that clients wanting to build a custom duration type (say a nanosecond</font>
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<font color="#c80000">// represented by a double) would have to write:</font>
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<font color="#c80000">//</font>
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<font color="#c80000">// duration<double, 1, 1000000000LL></font>
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<font color="#c80000">//</font>
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<font color="#c80000">// instead of:</font>
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<font color="#c80000">//</font>
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<font color="#c80000">// duration<double, nano></font>
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<font color="#c80000">//</font>
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<font color="#c80000">// This lack of syntatic niceness, along with the loss of functionality in the reuse of</font>
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<font color="#c80000">// ratio in user-written code seems to indicate that the loss of ratio would be a sizeable</font>
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<font color="#c80000">// loss to client code.</font>
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template <intmax_t N, intmax_t D = 1>
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class ratio
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{
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<font color="#c80000">// For every possible value of N and D, abs(N) >= 0 and abs(D) > 0</font>
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static_assert(__static_abs<N>::value >= 0, "ratio numerator is out of range");
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static_assert(__static_abs<D>::value > 0, "ratio denominator is out of range");
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public:
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static const intmax_t num; <font color="#c80000">// Reduced by greatest common divisor of N and D, has sign of sign(N) * sign(D)</font>
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static const intmax_t den; <font color="#c80000">// Reduced by greatest common divisor of N and D, always positive</font>
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<font color="#c80000">// When num == 0, den == 1</font>
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};
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<font color="#c80000">// The static_asserts in ratio are there to catch any values which have a negative absolute value.</font>
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<font color="#c80000">// In a typical 2's complement representation this is only LLONG_MIN. The reason for prohibiting</font>
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<font color="#c80000">// this value is because ratio must take the absolute values of its arguments and generally depends</font>
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<font color="#c80000">// on that number being non-negative in order to maintain invariants such as den > 0.</font>
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<font color="#c80000">// convenience typedefs</font>
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typedef ratio<1, 1000000000000000000000000> yocto; <font color="#c80000">// conditionally supported</font>
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typedef ratio<1, 1000000000000000000000> zepto; <font color="#c80000">// conditionally supported</font>
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typedef ratio<1, 1000000000000000000> atto;
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typedef ratio<1, 1000000000000000> femto;
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typedef ratio<1, 1000000000000> pico;
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typedef ratio<1, 1000000000> nano;
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typedef ratio<1, 1000000> micro;
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typedef ratio<1, 1000> milli;
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typedef ratio<1, 100> centi;
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typedef ratio<1, 10> deci;
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typedef ratio< 10, 1> deca;
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typedef ratio< 100, 1> hecto;
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typedef ratio< 1000, 1> kilo;
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typedef ratio< 1000000, 1> mega;
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typedef ratio< 1000000000, 1> giga;
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typedef ratio< 1000000000000, 1> tera;
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typedef ratio< 1000000000000000, 1> peta;
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typedef ratio< 1000000000000000000, 1> exa;
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typedef ratio< 1000000000000000000000, 1> zetta; <font color="#c80000">// conditionally supported</font>
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typedef ratio<1000000000000000000000000, 1> yotta; <font color="#c80000">// conditionally supported</font>
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<font color="#c80000">// Compile time arithmetic and comparisons should either avoid overflow or not compile</font>
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template <class R1, class R2>
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requires R1 and R2 are instantiations of ratio
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struct ratio_add
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{
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typedef ratio<pseudo code: R1 + R2> type;
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};
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template <class R1, class R2>
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requires R1 and R2 are instantiations of ratio
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struct ratio_subtract
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{
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typedef ratio<pseudo code: R1 - R2> type;
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};
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template <class R1, class R2>
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requires R1 and R2 are instantiations of ratio
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struct ratio_multiply
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{
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typedef ratio<pseudo code: R1 * R2> type;
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};
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template <class R1, class R2>
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requires R1 and R2 are instantiations of ratio
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struct ratio_divide
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{
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typedef ratio<pseudo code: R1 / R2> type;
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};
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template <class R1, class R2>
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requires R1 and R2 are instantiations of ratio
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struct ratio_equal
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: public integral_constant<bool, pseudo code: R1 == R2> {};
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template <class R1, class R2>
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requires R1 and R2 are instantiations of ratio
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struct ratio_not_equal
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: public integral_constant<bool, !ratio_equal<R1, R2>::value> {};
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template <class R1, class R2>
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requires R1 and R2 are instantiations of ratio
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struct ratio_less
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: public integral_constant<bool, pseudo code: R1 < R2> {};
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template <class R1, class R2>
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requires R1 and R2 are instantiations of ratio
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struct ratio_less_equal
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: public integral_constant<bool, !ratio_less<R2, R1>::value> {};
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template <class R1, class R2>
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requires R1 and R2 are instantiations of ratio
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struct ratio_greater
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: public integral_constant<bool, ratio_less<R2, R1>::value> {};
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template <class R1, class R2>
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requires R1 and R2 are instantiations of ratio
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struct ratio_greater_equal
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: public integral_constant<bool, !ratio_less<R1, R2>::value> {};
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namespace datetime
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{
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<font color="#c80000">// duration customization traits</font>
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<font color="#c80000">// Authors of arithmetic emulation types should specialize treat_as_floating_point</font>
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<font color="#c80000">// if their class emulates floating point and they want to use it as a duration's</font>
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<font color="#c80000">// representation.</font>
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template <class Rep> struct treat_as_floating_point
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: is_floating_point<Rep> {};
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<font color="#c80000">// Authors of arithmetic emulation types should specialize duration_values</font>
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<font color="#c80000">// if they want to use it as a duration's representation, and the default</font>
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<font color="#c80000">// definition of duration_values does not have the correct behavior.</font>
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template <class Rep>
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struct duration_values
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{
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public:
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static constexpr Rep zero() {return Rep(0);}
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static constexpr Rep max() {return numeric_limits<Rep>::max();}
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static constexpr Rep min() {return -max();}
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};
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<font color="#c80000">// Note: Rep(0) instead of Rep() is used for zero() because the author of Rep may</font>
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<font color="#c80000">// chose to have Rep() refer to an inderminant or unitialized value.</font>
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<font color="#c80000">// duration</font>
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<font color="#c80000">// A duration has a representation and a period.</font>
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<font color="#c80000">// </font>
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<font color="#c80000">// The representation is an arithmetic type, or a class emulating an arithmetic type.</font>
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<font color="#c80000">//</font>
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<font color="#c80000">// The period is the rational number of seconds between "ticks" of the duration. The</font>
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<font color="#c80000">// duration simply holds a count of the elapsed number of ticks (using the</font>
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<font color="#c80000">// representation), and that is related to seconds by multiplying by the period.</font>
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<font color="#c80000">// Note, this multiplication is only required when one needs to convert between</font>
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<font color="#c80000">// durations with different tick periods (e.g. milliseconds to microseconds).</font>
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<font color="#c80000">// </font>
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<font color="#c80000">// A duration has defalt construction and default copy semantics. One can also explicitly</font>
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<font color="#c80000">// construct a duration from its representation or something implicitly convertible to</font>
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<font color="#c80000">// its representation. If the representation is integral (or emulated integral) the</font>
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<font color="#c80000">// duration may not be constructed from a floating point (or emulated floating point)</font>
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<font color="#c80000">// type, even if that type is impilcitly convertible to the representation (the client</font>
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<font color="#c80000">// must explicitly convert such an argument as they pass it to the constructor if such</font>
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<font color="#c80000">// a conversion is desired).</font>
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<font color="#c80000">// </font>
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<font color="#c80000">// A duration may be implicitly constructible from another duration if the representations</font>
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<font color="#c80000">// of the two durations meet certain requirements. Let the representation of this duration</font>
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<font color="#c80000">// be Rep1 and the representation of the other duration be Rep2. Example representations</font>
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<font color="#c80000">// include int, long long, double, or a user-defined class which emulates one of these</font>
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<font color="#c80000">// arithmetic types. To qualify for implicit constructability Rep1 must be explicitly</font>
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<font color="#c80000">// constructible from Rep2. Note that implicit constructibility of Rep1 from Rep2 is not</font>
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<font color="#c80000">// required for this implicit construction between durations. Additionally the trait</font>
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<font color="#c80000">// common_type<Rep1, Rep2>::type must be well defined. If a conditional expression involving</font>
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<font color="#c80000">// these two types isn't valid, there must exist a common_type specialization which makes</font>
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<font color="#c80000">// the trait valid.</font>
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<font color="#c80000">// </font>
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<font color="#c80000">// The requirements put on the relationship between Rep1 and Rep2 are intended to be minimal,</font>
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<font color="#c80000">// and not require implicit conversions (which could be considered error prone by the author</font>
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<font color="#c80000">// of either of these representations).</font>
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<font color="#c80000">// </font>
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<font color="#c80000">// In addition to the above relationship between the representations, implicit constructability</font>
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<font color="#c80000">// also depends on whether the representation is considered floating point (or emulated floating</font>
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<font color="#c80000">// point) or integral (or emulated integral).</font>
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<font color="#c80000">// </font>
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<font color="#c80000">// If a duration has a floating point (or emulated floating point) representation it</font>
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<font color="#c80000">// is implicitly constructible from all other durations of any period (as long as</font>
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<font color="#c80000">// the representations are compatible as described above).</font>
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<font color="#c80000">// </font>
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<font color="#c80000">// If a duration has an integral (or emulated integral) representation it is implicitly</font>
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<font color="#c80000">// constructible from other integral-based durations which have a period which will exactly convert</font>
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<font color="#c80000">// to the period of this duration with no truncation error. More specifically, if the</font>
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<font color="#c80000">// period of this duration is P1, and the period of the other duration is P2, this</font>
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<font color="#c80000">// duration is implicitly constructible from the other duration if P2/P1 is a whole number</font>
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<font color="#c80000">// (as long as the representations are compatible as described above). Example:</font>
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<font color="#c80000">// microseconds has a period p1 = 1/1000000 seconds. milliseconds has a period</font>
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<font color="#c80000">// P2 = 1/1000 seconds. P2/P1 is (1/1000)/(1/1000000) = 1000000/1000 = 1000.</font>
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<font color="#c80000">// Therefore microseconds will implicitly construct from milliseconds (but not vice-versa).</font>
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<font color="#c80000">//</font>
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<font color="#c80000">// These rules involving integral representations are meant to prevent accidental truncatation</font>
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<font color="#c80000">// error. If truncation error is desired, a duration_cast facility is available to force it.</font>
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<font color="#c80000">// Example:</font>
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<font color="#c80000">// milliseconds ms(3); // ok, ms.count() == 3, which is 0.003 seconds</font>
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<font color="#c80000">// microseconds us = ms; // ok, us.count() == 3000 which is 0.003000 seconds</font>
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<font color="#c80000">// ++us; // ok, us.count() == 3001 which is 0.003001 seconds</font>
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<font color="#c80000">// ms = us; // won't compile, might truncate</font>
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<font color="#c80000">// ms = duration_cast<milliseconds>(us); // ok, ms.count() = 3, truncated a microsecond</font>
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<font color="#c80000">// </font>
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<font color="#c80000">// A duration has a single observer: rep count() const; which returns the stored</font>
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<font color="#c80000">// representation which holds the number of elapsed "ticks".</font>
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<font color="#c80000">// </font>
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<font color="#c80000">// A duration supports the following member arithmetic:</font>
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<font color="#c80000">// </font>
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<font color="#c80000">// duration operator+() const;</font>
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<font color="#c80000">// duration operator-() const;</font>
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<font color="#c80000">// duration& operator++();</font>
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<font color="#c80000">// duration operator++(int);</font>
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<font color="#c80000">// duration& operator--();</font>
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<font color="#c80000">// duration operator--(int);</font>
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<font color="#c80000">// </font>
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<font color="#c80000">// duration& operator+=(duration d);</font>
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<font color="#c80000">// duration& operator-=(duration d);</font>
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<font color="#c80000">// </font>
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<font color="#c80000">// duration& operator*=(rep rhs);</font>
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<font color="#c80000">// duration& operator/=(rep rhs);</font>
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<font color="#c80000">//</font>
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<font color="#c80000">// The arithmetic simply manipulates the "tick" count in the obvious way (e.g. operator++</font>
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<font color="#c80000">// increments the tick count by 1).</font>
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<font color="#c80000">// </font>
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<font color="#c80000">// A duration supports the following non-member arithmetic.</font>
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<font color="#c80000">// Let D1 represent duration<Rep1, Period1> and D2 represent duration<Rep2, Period2>.</font>
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<font color="#c80000">// </font>
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<font color="#c80000">// common_type<D1, D2>::type operator+( D1, D2); // returns a duration</font>
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<font color="#c80000">// common_type<D1, D2>::type operator-( D1, D2); // returns a duration</font>
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<font color="#c80000">// duration<common_type<D1::rep,Rep2>::type, D1::period> operator*( D1, Rep2); // returns a duration</font>
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<font color="#c80000">// duration<common_type<D1::rep,Rep2>::type, D1::period> operator*(Rep2, D1); // returns a duration</font>
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|
<font color="#c80000">// duration<common_type<D1::rep,Rep2>::type, D1::period> operator/( D1, Rep2); // returns a duration</font>
|
|
<font color="#c80000">// common_type<D1::rep, D2::rep>::type operator/( D1, D2); // returns a scalar</font>
|
|
<font color="#c80000">// </font>
|
|
<font color="#c80000">// A duration D1 is fully equality and less-than comparable with any other duration D2, as</font>
|
|
<font color="#c80000">// long as common_type<D1::rep, D2::rep> is well defined.</font>
|
|
<font color="#c80000">// Example:</font>
|
|
<font color="#c80000">// milliseconds ms(3); // ms.count() == 3, which is 0.003 seconds</font>
|
|
<font color="#c80000">// microseconds us = ms; // us.count() == 3000 which is 0.003000 seconds</font>
|
|
<font color="#c80000">// --us; // us.count() == 2999 which is 0.002999 seconds</font>
|
|
<font color="#c80000">// assert(ms != us); // 3 milliseconds is not equal to 2999 microseconds</font>
|
|
<font color="#c80000">// assert(ms > us); // 3 milliseconds is greater than 2999 microseconds</font>
|
|
<font color="#c80000">// ++us; // us.count() == 3000 which is 0.003000 seconds</font>
|
|
<font color="#c80000">// assert(ms == us); // 3 milliseconds is equal to 3000 microseconds</font>
|
|
<font color="#c80000">//</font>
|
|
<font color="#c80000">// Durations based on floating point representations are subject to round off error precisely the</font>
|
|
<font color="#c80000">// same way their representations are.</font>
|
|
<font color="#c80000">// </font>
|
|
<font color="#c80000">// Arithmetic and comparisons among integral-based durations is not subject to truncation error or</font>
|
|
<font color="#c80000">// round off error. If truncation error would result from the arithmetic (say</font>
|
|
<font color="#c80000">// by converting a smaller period duration to a larger one) the expression will</font>
|
|
<font color="#c80000">// not compile (unless duration_cast is used). If one performs arithmetic</font>
|
|
<font color="#c80000">// involving the duration's representation (such as division), then truncation</font>
|
|
<font color="#c80000">// will happen implicitly.</font>
|
|
<font color="#c80000">// </font>
|
|
<font color="#c80000">// Overflow error may silently happen with a duration. The std-defined durations</font>
|
|
<font color="#c80000">// have a minimum range of +/- 292 years.</font>
|
|
<font color="#c80000">// </font>
|
|
<font color="#c80000">// A duration is a thin wrapper around its representation. sizeof(duration<Rep, Period>) == sizeof(Rep).</font>
|
|
<font color="#c80000">// </font>
|
|
<font color="#c80000">// A duration can represent units as small as 10^-18 seconds (attoseconds) and as large as 10^18 seconds</font>
|
|
<font color="#c80000">// (about 30 billion years). The range of a duration is based on the range of its representation</font>
|
|
<font color="#c80000">// combined with its period.</font>
|
|
|
|
<font color="#c80000">// The cost of not including the flexibility to represent different "tick periods" in the duration</font>
|
|
<font color="#c80000">// type would be a great loss of both flexibility, convenience and safety for the client. For example</font>
|
|
<font color="#c80000">// if had just one duration type which counted nanoseconds (no matter how that count was represented),</font>
|
|
<font color="#c80000">// then clients could never have the ability to traffic in picoseconds. And the only hope of reaching</font>
|
|
<font color="#c80000">// beyond a +/- 292 year range with nanoseconds is to increase the number of bits in the representation</font>
|
|
<font color="#c80000">// (such as a long long). Furthermore, if the client wanted to traffic in units larger than a nanosecond</font>
|
|
<font color="#c80000">// (e.g. seconds) for convience, they would likely need to set up their own conversion constants and</font>
|
|
<font color="#c80000">// convert manually.</font>
|
|
<font color="#c80000">//</font>
|
|
<font color="#c80000">// If the conversion constants are specified at run time, rather than as compile time integral constants,</font>
|
|
<font color="#c80000">// then the client suffers a significant performance penalty as for every conversion one will have to</font>
|
|
<font color="#c80000">// perform both a multiplication and a division. In contrast, when converting among any two units of</font>
|
|
<font color="#c80000">// the set (hours, minutes, seconds, milliseconds, microseconds, nanoseconds), there need be only a</font>
|
|
<font color="#c80000">// single multiplication *or* division (never both). This proposal makes every unit conversion as</font>
|
|
<font color="#c80000">// efficient as if it had been coded by hand (see duration_cast). Furthermore duration_cast encapsulates</font>
|
|
<font color="#c80000">// all unit conversions within a single uniform-syntax function which is easily used in generic code. There</font>
|
|
<font color="#c80000">// is no need (or motivation) to set up a "hub-and-spoke" conversion regimen, so that the number of conversion</font>
|
|
<font color="#c80000">// functions is O(N) rather than O(N^2).</font>
|
|
|
|
template <class Rep, class Period = ratio<1>>
|
|
requires Rep is an arithmetic type, or a class emulating an arithmetic type,
|
|
and not an instantiation of duration
|
|
requires Period is an instantiation of ratio and represents a positive fraction
|
|
class duration
|
|
{
|
|
public:
|
|
typedef Rep rep;
|
|
typedef Period period;
|
|
private:
|
|
rep rep_; <font color="#c80000">// exposition only</font>
|
|
public:
|
|
<font color="#c80000">// construction / destruction</font>
|
|
duration() = default;
|
|
template <class Rep2>
|
|
requires is_convertible<Rep2, rep>::value &&
|
|
(treat_as_floating_point<rep>::value ||
|
|
!treat_as_floating_point<rep>::value && !treat_as_floating_point<Rep2>::value)
|
|
explicit duration(const Rep2& r);
|
|
~duration() = default;
|
|
|
|
<font color="#c80000">// copy semantics</font>
|
|
duration(const duration&) = default;
|
|
duration& operator=(const duration&) = default;
|
|
|
|
<font color="#c80000">// conversions</font>
|
|
template <class Rep2, class Period2>
|
|
requires Rep2 is explicitly convertible to rep &&
|
|
(treat_as_floating_point<rep>::value ||
|
|
!treat_as_floating_point<Rep2>::value && ratio_divide<Period2, period>::type::den == 1)
|
|
duration(const duration<Rep2, Period2>& d);
|
|
|
|
<font color="#c80000">// observer</font>
|
|
|
|
rep count() const;
|
|
|
|
<font color="#c80000">// arithmetic</font>
|
|
|
|
duration operator+() const;
|
|
duration operator-() const;
|
|
duration& operator++();
|
|
duration operator++(int);
|
|
duration& operator--();
|
|
duration operator--(int);
|
|
|
|
duration& operator+=(const duration& d);
|
|
duration& operator-=(const duration& d);
|
|
|
|
duration& operator*=(const rep& rhs);
|
|
duration& operator/=(const rep& rhs);
|
|
|
|
<font color="#c80000">// special values</font>
|
|
|
|
static constexpr duration zero();
|
|
static constexpr duration min();
|
|
static constexpr duration max();
|
|
};
|
|
|
|
<font color="#c80000">// convenience typedefs</font>
|
|
|
|
typedef duration<int_least64_t, nano> nanoseconds; <font color="#c80000">// 10^-9 seconds</font>
|
|
typedef duration<int_least55_t, micro> microseconds; <font color="#c80000">// 10^-6 seconds</font>
|
|
typedef duration<int_least45_t, milli> milliseconds; <font color="#c80000">// 10^-3 seconds</font>
|
|
typedef duration<int_least35_t > seconds; <font color="#c80000">// 1 second</font>
|
|
typedef duration<int_least29_t, ratio< 60>> minutes; <font color="#c80000">// 60 seconds</font>
|
|
typedef duration<int_least23_t, ratio<3600>> hours; <font color="#c80000">// 3600 seconds</font>
|
|
|
|
<font color="#c80000">// duration_cast can be used to force a conversion between two durations (assuming</font>
|
|
<font color="#c80000">// the source representation can be explicitly converted to the target representation).</font>
|
|
<font color="#c80000">// Not all integral-based durations are implicitly convertible to another (to</font>
|
|
<font color="#c80000">// avoid accidental truncation error). When truncation error is desired, the client</font>
|
|
<font color="#c80000">// uses duration_cast to explicitly request the non-exact conversion. When</font>
|
|
<font color="#c80000">// duration_cast is used to convert between durations which have an implicit conversion,</font>
|
|
<font color="#c80000">// the behavior and performance of the conversion using duration_cast is identical to</font>
|
|
<font color="#c80000">// that of the implicit conversion.</font>
|
|
|
|
template <class ToDuration, class Rep, class Period>
|
|
requires ToDuration is an instantiation of duration
|
|
ToDuration duration_cast(const duration<Rep, Period>& fd);
|
|
|
|
<font color="#c80000">// Examples:</font>
|
|
<font color="#c80000">// microseconds us(3500); // 3500 microseconds</font>
|
|
<font color="#c80000">// milliseconds ms = us; // Does not compile (implicit truncation)</font>
|
|
<font color="#c80000">// milliseconds ms = duration_cast<milliseconds>(us); // 3 milliseconds (explicit truncation)</font>
|
|
<font color="#c80000">// us = ms; // 3000 microseconds</font>
|
|
<font color="#c80000">// us = duration_cast<microseconds>(ms); // 3000 microseconds</font>
|
|
|
|
} <font color="#c80000">// datetime</font>
|
|
|
|
<font color="#c80000">// Given two durations: duration<Rep1, Period1> and duration<Rep2, Period2>, the common_type</font>
|
|
<font color="#c80000">// of those two durations is a duration with a representation of common_type<Rep1, Rep2>,</font>
|
|
<font color="#c80000">// and a period which is the "greatest common period" of Period1 and Period2. The GCP</font>
|
|
<font color="#c80000">// (Greatest Common Period) of Period1 and Period2 is the largest period which will divide</font>
|
|
<font color="#c80000">// both Period1 and Period2 evenly (and is often equivalent to the minimum of Period1 and</font>
|
|
<font color="#c80000">// Period2). This can be computed (by the implementation at compile time) by</font>
|
|
<font color="#c80000">// GCD(Period1::num, Period2::num) / LCM(Period1::den, Period2::den) where GCD is</font>
|
|
<font color="#c80000">// "Greatest Common Divisor" and LCM is "Least Common Multiple".</font>
|
|
|
|
template <class Rep1, class Period1, class Rep2, class Period2>
|
|
struct common_type<datetime::duration<Rep1, Period1>, datetime::duration<Rep2, Period2> >
|
|
{
|
|
typedef datetime::duration<typename common_type<Rep1, Rep2>::type,
|
|
ratio<GCD(Period1::num, Period2::num), LCM(Period1::den, Period2::den)>> type;
|
|
};
|
|
|
|
<font color="#c80000">// Note: For any two durations D1 and D2, they will both exactly convert to common_type<D1, D2>::type.</font>
|
|
<font color="#c80000">// common_type<D1, D2>::type will have the largest possible period to make this possible, and</font>
|
|
<font color="#c80000">// may be the same type as D1 or D2. Examples:</font>
|
|
<font color="#c80000">// common_type<minutes, microseconds>::type is microseconds.</font>
|
|
<font color="#c80000">// common_type<milliseconds, microseconds>::type is microseconds.</font>
|
|
<font color="#c80000">// common_type<nanoseconds, microseconds>::type is nanoseconds.</font>
|
|
<font color="#c80000">//</font>
|
|
<font color="#c80000">// A more complex example:</font>
|
|
<font color="#c80000">// common_type< duration<long, milli>, duration<int, ratio<1,30>> >::type is</font>
|
|
<font color="#c80000">// duration<long, ratio<1,3000>>. And both duration<long, milli> and </font>
|
|
<font color="#c80000">// duration<int, ratio<1,30>> will exactly convert to duration<long, ratio<1,3000>>.</font>
|
|
<font color="#c80000">// The former multitplies its representation by 3L and the latter converts its</font>
|
|
<font color="#c80000">// representation to long and multiplies that result by 1000L. There exists no</font>
|
|
<font color="#c80000">// duration with a larger period such that both duration<long, milli> and</font>
|
|
<font color="#c80000">// duration<int, ratio<1,30>> will exactly convert to it.</font>
|
|
|
|
namespace datetime {
|
|
|
|
template <class Rep1, class Period1, class Rep2, class Period2>
|
|
bool operator==(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
|
|
template <class Rep1, class Period1, class Rep2, class Period2>
|
|
bool operator!=(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
|
|
template <class Rep1, class Period1, class Rep2, class Period2>
|
|
bool operator< (const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
|
|
template <class Rep1, class Period1, class Rep2, class Period2>
|
|
bool operator<=(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
|
|
template <class Rep1, class Period1, class Rep2, class Period2>
|
|
bool operator> (const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
|
|
template <class Rep1, class Period1, class Rep2, class Period2>
|
|
bool operator>=(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
|
|
|
|
template <class Rep1, class Period1, class Rep2, class Period2>
|
|
typename common_type<duration<Rep1, Period1>, duration<Rep2, Period2> >::type
|
|
operator+(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
|
|
|
|
template <class Rep1, class Period1, class Rep2, class Period2>
|
|
typename common_type<duration<Rep1, Period1>, duration<Rep2, Period2> >::type
|
|
operator-(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
|
|
|
|
template <class Rep1, class Period, class Rep2>
|
|
requires Constructible<Rep1, typename common_type<Rep1, Rep2>::type>::value> &&
|
|
Constructible<Rep2, typename common_type<Rep1, Rep2>::type>::value>
|
|
duration<typename common_type<Rep1, Rep2>::type, Period>
|
|
operator*(const duration<Rep, Period>& d, const Rep2& s);
|
|
|
|
template <class Rep1, class Period, class Rep2>
|
|
requires Constructible<Rep1, typename common_type<Rep1, Rep2>::type>::value> &&
|
|
Constructible<Rep2, typename common_type<Rep1, Rep2>::type>::value>
|
|
duration<typename common_type<Rep1, Rep2>::type, Period>
|
|
operator*(const Rep2& s, const duration<Rep, Period>& d);
|
|
|
|
template <class Rep1, class Period, class Rep2>
|
|
requires Rep2 is not a duration &&
|
|
Constructible<Rep1, typename common_type<Rep1, Rep2>::type>::value> &&
|
|
Constructible<Rep2, typename common_type<Rep1, Rep2>::type>::value>
|
|
duration<typename common_type<Rep1, Rep2>::type, Period>
|
|
operator/(const duration<Rep, Period>& d, const Rep2& s);
|
|
|
|
<font color="#c80000">// Note: the above 3 signatures can be approximated with is_convertible if concepts do not</font>
|
|
<font color="#c80000">// make it into the language. Requiring only *explicit* convertibility between the Rep</font>
|
|
<font color="#c80000">// types is strongly desired. One way or another, Rep2 must be constrained. Otherwise</font>
|
|
<font color="#c80000">// the operators are overly generic.</font>
|
|
|
|
template <class Rep1, class Period1, class Rep2, class Period2>
|
|
typename common_type<Rep1, Rep2>::type
|
|
operator/(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
|
|
|
|
<font color="#c80000">// time_point</font>
|
|
|
|
<font color="#c80000">// A time_point represents an epoch plus or minus a duration. The relationship between a time_point</font>
|
|
<font color="#c80000">// which represents "now" and the time_point's epoch is obtained via a clock. Each time_point is</font>
|
|
<font color="#c80000">// tied to a specific clock. Thus, for any time_point, one can find the duration between that</font>
|
|
<font color="#c80000">// point in time and now, and between that point in time, and its epoch.</font>
|
|
<font color="#c80000">// </font>
|
|
<font color="#c80000">// A time_point may be default constructed. This time_point represents the epoch. time_point has</font>
|
|
<font color="#c80000">// default copy semantics.</font>
|
|
<font color="#c80000">// </font>
|
|
<font color="#c80000">// time_point may be explicitly constructed by a duration having the same representation and period as</font>
|
|
<font color="#c80000">// the time_point. Any other duration which is implicitly convertible to the time_point's "native" duration can</font>
|
|
<font color="#c80000">// also be used to explicitly construct the time_point. The meaning of this construction is identical to</font>
|
|
<font color="#c80000">// time_point() + d.</font>
|
|
<font color="#c80000">//</font>
|
|
<font color="#c80000">// A time_point is implicitly constructible from another time_point if they share the same clock,</font>
|
|
<font color="#c80000">// and the duration of this time_point is implicitly constructible from the duration of the other</font>
|
|
<font color="#c80000">// time_point. A time_point constructed in this fashion will compare equal to the source time_point</font>
|
|
<font color="#c80000">// after the construction.</font>
|
|
<font color="#c80000">// </font>
|
|
<font color="#c80000">// A time_point supports the following member arithmetic:</font>
|
|
<font color="#c80000">// </font>
|
|
<font color="#c80000">// time_point& operator+=(duration d);</font>
|
|
<font color="#c80000">// time_point& operator-=(duration d);</font>
|
|
<font color="#c80000">// </font>
|
|
<font color="#c80000">// A time_point supports the following non-member arithmetic.</font>
|
|
<font color="#c80000">// Let T1 represent time_point<Clock, Duration1>,</font>
|
|
<font color="#c80000">// T2 represent time_point<Clock, Duration2>,</font>
|
|
<font color="#c80000">// and D represent duration<Rep3, Period3>. Note that T1 and T2 must have the same Clock.</font>
|
|
<font color="#c80000">// Attempts to interoperate times having different clocks results in a compile time failure.</font>
|
|
<font color="#c80000">// </font>
|
|
<font color="#c80000">// T2 operator+(T1, D); // return type is a time_point</font>
|
|
<font color="#c80000">// T2 operator+( D, T1); // return type is a time_point</font>
|
|
<font color="#c80000">// T2 operator-(T1, D); // return type is a time_point</font>
|
|
<font color="#c80000">// D operator-(T1, T2); // return type is a duration</font>
|
|
<font color="#c80000">// </font>
|
|
<font color="#c80000">// A time_point T1 is fully equality and less-than comparable with any other time_point T2 which</font>
|
|
<font color="#c80000">// has the same clock, and for which their durations are comparable.</font>
|
|
<font color="#c80000">// </font>
|
|
<font color="#c80000">// Times based on floating point representations are subject to round off error precisely the</font>
|
|
<font color="#c80000">// same way their representations are.</font>
|
|
<font color="#c80000">// </font>
|
|
<font color="#c80000">// Times based on integral representations are not subject to truncation error or round off</font>
|
|
<font color="#c80000">// error. A compile time error will result if truncation error is possible. Truncation error</font>
|
|
<font color="#c80000">// is only possible with construction or the member arithmetic (and won't compile). Non-member</font>
|
|
<font color="#c80000">// arithmetic and comparison is always exact. Overflow error with integral based times remains a</font>
|
|
<font color="#c80000">// possibility.</font>
|
|
<font color="#c80000">// </font>
|
|
<font color="#c80000">// A time_point is a thin wrapper around its representation.</font>
|
|
<font color="#c80000">// sizeof(time_point<Clock, Duration>) == sizeof(Duration) == sizeof(Duration::rep).</font>
|
|
<font color="#c80000">// </font>
|
|
<font color="#c80000">// A time_point can represent units as small as 10^-18 seconds and as large as 10^18 seconds. The range</font>
|
|
<font color="#c80000">// of a time_point is based on the range of its representation combined with its period.</font>
|
|
<font color="#c80000">//</font>
|
|
<font color="#c80000">// Because no two clocks report the exact same time, even clocks which nominally have the same</font>
|
|
<font color="#c80000">// epoch, are considered by this framework to have different epochs, if only by a few nanoseconds.</font>
|
|
<font color="#c80000">// Converting time_points from one clock to another will involve synchronization of the clocks,</font>
|
|
<font color="#c80000">// which can be viewed as a synchronization of their epochs. Such synchronization is clock specific</font>
|
|
<font color="#c80000">// and beyond the scope of this API. A future API, or a platform specific API, can easily</font>
|
|
<font color="#c80000">// write such a synchronization API, basing it on this API.</font>
|
|
|
|
<font color="#c80000">// The cost of not including a time_point class is the lack of the ability to safely interact with</font>
|
|
<font color="#c80000">// the concept of "epoch + duration". Without a separate type, the client is in danger of accidently</font>
|
|
<font color="#c80000">// writing code that boils down to "epoch1 + duration1" + "epoch2 + duration2". Algebraically this</font>
|
|
<font color="#c80000">// results in epoch1+epoch2 as a subexpression which is likely to be completely without meaning. What</font>
|
|
<font color="#c80000">// would it mean to add New Years 1970 to the point in time at which your computer booted up? Or for</font>
|
|
<font color="#c80000">// that matter, what is the meaning of "New Years 1970" + "New Years 1970"?</font>
|
|
<font color="#c80000">//</font>
|
|
<font color="#c80000">// Additionally this would force the duration type to play double duty as a time_point leading to</font>
|
|
<font color="#c80000">// client confusion. For example POSIX has timespec represent a duration in nanosleep, and yet the</font>
|
|
<font color="#c80000">// same type is used as a time_point in pthread_cond_timedwait and pthread_mutex_timedlock. The</font>
|
|
<font color="#c80000">// confusion seems even more likely with a function such as clock_nanosleep where timespec can mean</font>
|
|
<font color="#c80000">// either a duration or a time_point depending upon another argument to the function.</font>
|
|
<font color="#c80000">//</font>
|
|
<font color="#c80000">// In C++ we can easily mitigate such errors by detecting them at compile time. This is done through</font>
|
|
<font color="#c80000">// the use of distinct types for these distinct concepts (even though both types have identical layout!).</font>
|
|
|
|
template <class Clock, class Duration = typename Clock::duration>
|
|
requires Duration is an instantiation of duration
|
|
class time_point
|
|
{
|
|
public:
|
|
typedef Clock clock;
|
|
typedef Duration duration;
|
|
typedef typename duration::rep rep;
|
|
typedef typename duration::period period;
|
|
private:
|
|
duration d_; <font color="#c80000">// exposition only</font>
|
|
|
|
public:
|
|
time_point(); <font color="#c80000">// has value "epoch"</font>
|
|
explicit time_point(const duration& d); <font color="#c80000">// same as time_point() + d</font>
|
|
|
|
<font color="#c80000">// conversions</font>
|
|
template <class Duration2>
|
|
requires Convertible<Duration2, duration>
|
|
time_point(const time_point<clock, Duration2>& t);
|
|
|
|
<font color="#c80000">// observer</font>
|
|
|
|
duration time_since_epoch() const;
|
|
|
|
<font color="#c80000">// arithmetic</font>
|
|
|
|
time_point& operator+=(const duration& d);
|
|
time_point& operator-=(const duration& d);
|
|
|
|
<font color="#c80000">// special values</font>
|
|
|
|
static time_point min();
|
|
static time_point max();
|
|
};
|
|
|
|
} <font color="#c80000">// datetime</font>
|
|
|
|
template <class Clock, class Duration1, class Duration2>
|
|
struct common_type<datetime::time_point<Clock, Duration1>, datetime::time_point<Clock, Duration2> >
|
|
{
|
|
typedef datetime::time_point<Clock, typename common_type<Duration1, Duration2>::type> type;
|
|
};
|
|
|
|
namespace datetime {
|
|
|
|
template <class ToDuration, class Clock, class Duration>
|
|
time_point<Clock, ToDuration> time_point_cast(const time_point<Clock, Duration>& t);
|
|
|
|
template <class Clock, class Duration1, class Duration2>
|
|
bool operator==(const time_point<Clock, Duration1>& lhs, const time_point<Clock, Duration2>& rhs);
|
|
template <class Clock, class Duration1, class Duration2>
|
|
bool operator!=(const time_point<Clock, Duration1>& lhs, const time_point<Clock, Duration2>& rhs);
|
|
template <class Clock, class Duration1, class Duration2>
|
|
bool operator< (const time_point<Clock, Duration1>& lhs, const time_point<Clock, Duration2>& rhs);
|
|
template <class Clock, class Duration1, class Duration2>
|
|
bool operator<=(const time_point<Clock, Duration1>& lhs, const time_point<Clock, Duration2>& rhs);
|
|
template <class Clock, class Duration1, class Duration2>
|
|
bool operator> (const time_point<Clock, Duration1>& lhs, const time_point<Clock, Duration2>& rhs);
|
|
template <class Clock, class Duration1, class Duration2>
|
|
bool operator>=(const time_point<Clock, Duration1>& lhs, const time_point<Clock, Duration2>& rhs);
|
|
|
|
template <class Clock, class Duration1, class Rep2, class Period2>
|
|
time_point<Clock, typename common_type<Duration1, duration<Rep2, Period2> >::type>
|
|
operator+(const time_point<Clock, Duration1>& lhs, const duration<Rep2, Period2>& rhs);
|
|
|
|
template <class Rep1, class Period1, class Clock, class Duration2>
|
|
time_point<Clock, typename common_type<duration<Rep1, Period1>, Duration2>::type>
|
|
operator+(const duration<Rep1, Period1>& lhs, const time_point<Clock, Duration2>& rhs);
|
|
|
|
template <class Clock, class Duration1, class Rep2, class Period2>
|
|
time_point<Clock, typename common_type<Duration1, duration<Rep2, Period2> >::type>
|
|
operator-(const time_point<Clock, Duration1>& lhs, const duration<Rep2, Period2>& rhs);
|
|
|
|
template <class Clock, class Duration1, class Duration2>
|
|
typename common_type<Duration1, Duration2>::type
|
|
operator-(const time_point<Clock, Duration1>& lhs, const time_point<Clock, Duration2>& rhs);
|
|
|
|
<font color="#c80000">// clocks</font>
|
|
|
|
<font color="#c80000">// A clock specifies a representation, and a period. These specifications are used to</font>
|
|
<font color="#c80000">// to define a clock's native duration and time_point types. A clock also has a function to get the current</font>
|
|
<font color="#c80000">// time_point. A clock need not have any state.</font>
|
|
|
|
<font color="#c80000">// The cost of not including separate types for clocks is that there is no better place to</font>
|
|
<font color="#c80000">// bundle the "native" duration and time_point types for a clock with the functionality to</font>
|
|
<font color="#c80000">// get the current time_point (what time is it now?). By bundling this information into a</font>
|
|
<font color="#c80000">// type, the extension to support multiple clocks is both easy and obvious. The ability to</font>
|
|
<font color="#c80000">// easily support multiple clocks in such a flexible yet simple and efficient manner is</font>
|
|
<font color="#c80000">// very important. A client might (for example) write code with the clock as a generic</font>
|
|
<font color="#c80000">// template parameter, and then easily experiment with different timers.</font>
|
|
|
|
class system_clock
|
|
{
|
|
public:
|
|
typedef <unspecified> rep;
|
|
typedef ratio<unspecified, unspecified> period;
|
|
typedef datetime::duration<rep, period> duration;
|
|
typedef datetime::time_point<system_clock> time_point;
|
|
static const bool is_mononontic = <unspecified>;
|
|
|
|
static time_point now();
|
|
|
|
<font color="#c80000">// Map to C API</font>
|
|
static time_t to_time_t (const time_point& t);
|
|
static time_point from_time_t(time_t t);
|
|
};
|
|
|
|
class monotonic_clock <font color="#c80000">// optional</font>
|
|
{
|
|
public:
|
|
typedef <unspecified> rep;
|
|
typedef ratio<unspecified, unspecified> period;
|
|
typedef datetime::duration<rep, period> duration;
|
|
typedef datetime::time_point<monotonic_clock> time_point;
|
|
static const bool is_mononontic = true;
|
|
|
|
static time_point now();
|
|
};
|
|
|
|
class high_resolution_clock <font color="#c80000">// optional</font>
|
|
{
|
|
public:
|
|
typedef <unspecified> rep;
|
|
typedef ratio<unspecified, unspecified> period;
|
|
typedef datetime::duration<rep, period> duration;
|
|
typedef datetime::time_point<high_resolution_clock> time_point;
|
|
static const bool is_mononontic = <unspecified>;
|
|
|
|
static time_point now();
|
|
};
|
|
|
|
<font color="#c80000">// Note: These clocks may be three separate types, or typedefs to one or two common types.</font>
|
|
|
|
} <font color="#c80000">// datetime</font>
|
|
|
|
<font color="#c80000">//////////////////////////</font>
|
|
<font color="#c80000">// Threading interface //</font>
|
|
<font color="#c80000">//////////////////////////</font>
|
|
|
|
<font color="#c80000">// timed_mutex</font>
|
|
|
|
struct timed_mutex
|
|
{
|
|
public:
|
|
timed_mutex();
|
|
~timed_mutex();
|
|
|
|
timed_mutex(const timed_mutex&) = delete;
|
|
timed_mutex& operator=(const timed_mutex&) = delete;
|
|
|
|
void lock();
|
|
bool try_lock();
|
|
template <class Rep, class Period>
|
|
bool try_lock_for(const datetime::duration<Rep, Period>& rel_time);
|
|
template <class Clock, class Duration>
|
|
bool try_lock_until(const datetime::time_point<Clock, Duration>& abs_time);
|
|
void unlock();
|
|
|
|
typedef unspecified native_handle_type; <font color="#c80000">// optional. example: pthread_mutex_t*</font>
|
|
native_handle_type native_handle(); <font color="#c80000">// optional</font>
|
|
};
|
|
|
|
<font color="#c80000">// recursive_timed_mutex</font>
|
|
|
|
struct recursive_timed_mutex
|
|
{
|
|
public:
|
|
recursive_timed_mutex();
|
|
~recursive_timed_mutex();
|
|
|
|
recursive_timed_mutex(const recursive_timed_mutex&) = delete;
|
|
recursive_timed_mutex& operator=(const recursive_timed_mutex&) = delete;
|
|
|
|
void lock();
|
|
bool try_lock();
|
|
template <class Rep, class Period>
|
|
bool try_lock_for(const datetime::duration<Rep, Period>& rel_time);
|
|
template <class Clock, class Duration>
|
|
bool try_lock_until(const datetime::time_point<Clock, Duration>& abs_time);
|
|
void unlock();
|
|
|
|
typedef unspecified native_handle_type; <font color="#c80000">// optional. example: pthread_mutex_t*</font>
|
|
native_handle_type native_handle(); <font color="#c80000">// optional</font>
|
|
};
|
|
|
|
<font color="#c80000">// unique_lock</font>
|
|
|
|
template <class Mutex>
|
|
class unique_lock
|
|
{
|
|
public:
|
|
typedef Mutex mutex_type;
|
|
|
|
unique_lock();
|
|
explicit unique_lock(mutex_type& m);
|
|
unique_lock(mutex_type& m, defer_lock_t);
|
|
unique_lock(mutex_type& m, try_to_lock_t);
|
|
unique_lock(mutex_type& m, adopt_lock_t);
|
|
template <class Rep, class Period>
|
|
unique_lock(mutex_type& m, const datetime::duration<Rep, Period>& rel_t);
|
|
template <class Clock, class Duration>
|
|
unique_lock(mutex_type& m, const datetime::time_point<Clock, Duration>& abs_time);
|
|
~unique_lock();
|
|
|
|
unique_lock(unique_lock const&) = delete;
|
|
unique_lock& operator=(unique_lock const&) = delete;
|
|
|
|
unique_lock(unique_lock&& u);
|
|
unique_lock& operator=(unique_lock&& u);
|
|
|
|
void lock();
|
|
bool try_lock();
|
|
template <class Rep, class Period>
|
|
bool try_lock_for(const datetime::duration<Rep, Period>& rel_t);
|
|
template <class Clock, class Duration>
|
|
bool try_lock_until(const datetime::time_point<Clock, Duration>& abs_time);
|
|
void unlock();
|
|
|
|
bool owns_lock() const;
|
|
operator unspecified-bool-type () const;
|
|
mutex_type* mutex() const;
|
|
|
|
void swap(unique_lock&& u);
|
|
mutex_type* release();
|
|
};
|
|
|
|
<font color="#c80000">// condition_variable</font>
|
|
|
|
class condition_variable
|
|
{
|
|
public:
|
|
|
|
condition_variable();
|
|
~condition_variable();
|
|
|
|
condition_variable(const condition_variable&) = delete;
|
|
condition_variable& operator=(const condition_variable&) = delete;
|
|
|
|
void notify_one();
|
|
void notify_all();
|
|
|
|
void wait(unique_lock<mutex>& lock);
|
|
template <class Predicate>
|
|
void wait(unique_lock<mutex>& lock, Predicate pred);
|
|
|
|
template <class Clock, class Duration>
|
|
bool wait_until(unique_lock<mutex>& lock,
|
|
const datetime::time_point<Clock, Duration>& abs_time);
|
|
template <class Clock, class Duration, class Predicate>
|
|
bool wait_until(unique_lock<mutex>& lock,
|
|
const datetime::time_point<Clock, Duration>& abs_time,
|
|
Predicate pred);
|
|
|
|
template <class Rep, class Period>
|
|
bool wait_for(unique_lock<mutex>& lock, const datetime::duration<Rep, Period>& rel_time);
|
|
template <class Rep, class Period, class Predicate>
|
|
bool wait_for(unique_lock<mutex>& lock, const datetime::duration<Rep, Period>& rel_time,
|
|
Predicate pred);
|
|
|
|
typedef pthread_cond_t* native_handle_type;
|
|
native_handle_type native_handle();
|
|
};
|
|
|
|
<font color="#c80000">// condition_variable_any</font>
|
|
|
|
class condition_variable_any
|
|
{
|
|
public:
|
|
|
|
condition_variable_any();
|
|
~condition_variable_any();
|
|
|
|
condition_variable_any(const condition_variable_any&) = delete;
|
|
condition_variable_any& operator=(const condition_variable_any&) = delete;
|
|
|
|
void notify_one();
|
|
void notify_all();
|
|
|
|
template <class Lock>
|
|
void wait(Lock& lock);
|
|
template <class Lock, class Predicate>
|
|
void wait(Lock& lock, Predicate pred);
|
|
|
|
template <class Lock, class Clock, class Duration>
|
|
bool wait_until(Lock& lock, const datetime::time_point<Clock, Duration>& abs_time);
|
|
template <class Lock, class Clock, class Duration, class Predicate>
|
|
bool wait_until(Lock& lock, const datetime::time_point<Clock, Duration>& abs_time,
|
|
Predicate pred);
|
|
|
|
template <class Lock, class Rep, class Period>
|
|
bool wait_for(Lock& lock, const datetime::duration<Rep, Period>& rel_time);
|
|
template <class Lock, class Rep, class Period, class Predicate>
|
|
bool wait_for(Lock& lock, const datetime::duration<Rep, Period>& rel_time, Predicate pred);
|
|
};
|
|
|
|
<font color="#c80000">// sleep</font>
|
|
|
|
namespace this_thread
|
|
{
|
|
|
|
template <class Rep, class Period>
|
|
void sleep_for(const datetime::duration<Rep, Period>& rel_time);
|
|
|
|
template <class Clock, class Duration>
|
|
void sleep_until(const datetime::time_point<Clock, Duration>& abs_time);
|
|
|
|
} <font color="#c80000">// this_thread</font>
|
|
|
|
} <font color="#c80000">// std</font>
|
|
|
|
*/</font>
|
|
|
|
#include <ctime>
|
|
#include <climits>
|
|
#include <inttypes.h>
|
|
#include <limits>
|
|
#include "type_traits"
|
|
|
|
#define decltype __typeof__
|
|
|
|
namespace std
|
|
{
|
|
|
|
<font color="#c80000">//////////////////////////////////////////////////////////</font>
|
|
<font color="#c80000">////////////////////// common_type ///////////////////////</font>
|
|
<font color="#c80000">//////////////////////////////////////////////////////////</font>
|
|
|
|
#define VARIADIC_COMMON_TYPE 0
|
|
|
|
#if VARIADIC_COMMON_TYPE == 0
|
|
|
|
template <class T, class U>
|
|
struct common_type
|
|
{
|
|
private:
|
|
static T t();
|
|
static U u();
|
|
public:
|
|
typedef decltype(true ? t() : u()) type;
|
|
};
|
|
|
|
#else
|
|
|
|
template <class ...T> struct common_type;
|
|
|
|
template <class T>
|
|
struct common_type<T>
|
|
{
|
|
typedef T type;
|
|
};
|
|
|
|
template <class T, class U>
|
|
struct common_type<T, U>
|
|
{
|
|
private:
|
|
static T t();
|
|
static U u();
|
|
public:
|
|
typedef decltype(true ? t() : u()) type;
|
|
};
|
|
|
|
template <class T, class U, class ...V>
|
|
struct common_type<T, U, V...>
|
|
{
|
|
typedef typename common_type<typename common_type<T, U>::type, V...>::type type;
|
|
};
|
|
|
|
#endif
|
|
|
|
<font color="#c80000">//////////////////////////////////////////////////////////</font>
|
|
<font color="#c80000">/////////////////////// ratio ////////////////////////////</font>
|
|
<font color="#c80000">//////////////////////////////////////////////////////////</font>
|
|
|
|
<font color="#c80000">// __static_gcd</font>
|
|
|
|
template <intmax_t X, intmax_t Y>
|
|
struct __static_gcd
|
|
{
|
|
static const intmax_t value = __static_gcd<Y, X % Y>::value;
|
|
};
|
|
|
|
template <intmax_t X>
|
|
struct __static_gcd<X, 0>
|
|
{
|
|
static const intmax_t value = X;
|
|
};
|
|
|
|
<font color="#c80000">// __static_lcm</font>
|
|
|
|
template <intmax_t X, intmax_t Y>
|
|
struct __static_lcm
|
|
{
|
|
static const intmax_t value = X / __static_gcd<X, Y>::value * Y;
|
|
};
|
|
|
|
template <intmax_t X>
|
|
struct __static_abs
|
|
{
|
|
static const intmax_t value = X < 0 ? -X : X;
|
|
};
|
|
|
|
template <intmax_t X>
|
|
struct __static_sign
|
|
{
|
|
static const intmax_t value = X == 0 ? 0 : (X < 0 ? -1 : 1);
|
|
};
|
|
|
|
template <intmax_t X, intmax_t Y, intmax_t = __static_sign<Y>::value>
|
|
class __ll_add;
|
|
|
|
template <intmax_t X, intmax_t Y>
|
|
class __ll_add<X, Y, 1>
|
|
{
|
|
static const intmax_t min = (1LL << (sizeof(intmax_t) * CHAR_BIT - 1)) + 1;
|
|
static const intmax_t max = -min;
|
|
|
|
static char test[X <= max - Y];
|
|
<font color="#c80000">// static_assert(X <= max - Y, "overflow in __ll_add");</font>
|
|
public:
|
|
static const intmax_t value = X + Y;
|
|
};
|
|
|
|
template <intmax_t X, intmax_t Y>
|
|
class __ll_add<X, Y, 0>
|
|
{
|
|
public:
|
|
static const intmax_t value = X;
|
|
};
|
|
|
|
template <intmax_t X, intmax_t Y>
|
|
class __ll_add<X, Y, -1>
|
|
{
|
|
static const intmax_t min = (1LL << (sizeof(intmax_t) * CHAR_BIT - 1)) + 1;
|
|
static const intmax_t max = -min;
|
|
|
|
static char test[min - Y <= X];
|
|
<font color="#c80000">// static_assert(min - Y <= X, "overflow in __ll_add");</font>
|
|
public:
|
|
static const intmax_t value = X + Y;
|
|
};
|
|
|
|
template <intmax_t X, intmax_t Y, intmax_t = __static_sign<Y>::value>
|
|
class __ll_sub;
|
|
|
|
template <intmax_t X, intmax_t Y>
|
|
class __ll_sub<X, Y, 1>
|
|
{
|
|
static const intmax_t min = (1LL << (sizeof(intmax_t) * CHAR_BIT - 1)) + 1;
|
|
static const intmax_t max = -min;
|
|
|
|
static char test[min + Y <= X];
|
|
<font color="#c80000">// static_assert(min + Y <= X, "overflow in __ll_sub");</font>
|
|
public:
|
|
static const intmax_t value = X - Y;
|
|
};
|
|
|
|
template <intmax_t X, intmax_t Y>
|
|
class __ll_sub<X, Y, 0>
|
|
{
|
|
public:
|
|
static const intmax_t value = X;
|
|
};
|
|
|
|
template <intmax_t X, intmax_t Y>
|
|
class __ll_sub<X, Y, -1>
|
|
{
|
|
static const intmax_t min = (1LL << (sizeof(intmax_t) * CHAR_BIT - 1)) + 1;
|
|
static const intmax_t max = -min;
|
|
|
|
static char test[X <= max + Y];
|
|
<font color="#c80000">// static_assert(X <= max + Y, "overflow in __ll_sub");</font>
|
|
public:
|
|
static const intmax_t value = X - Y;
|
|
};
|
|
|
|
template <intmax_t X, intmax_t Y>
|
|
class __ll_mul
|
|
{
|
|
static const intmax_t nan = (1LL << (sizeof(intmax_t) * CHAR_BIT - 1));
|
|
static const intmax_t min = nan + 1;
|
|
static const intmax_t max = -min;
|
|
static const intmax_t __a_x = __static_abs<X>::value;
|
|
static const intmax_t __a_y = __static_abs<Y>::value;
|
|
|
|
static char test1[X != nan];
|
|
static char test2[Y != nan];
|
|
static char test[__a_x <= max / __a_y];
|
|
<font color="#c80000">// static_assert(X != nan && Y != nan && __a_x <= max / __a_y, "overflow in __ll_mul");</font>
|
|
public:
|
|
static const intmax_t value = X * Y;
|
|
};
|
|
|
|
template <intmax_t Y>
|
|
class __ll_mul<0, Y>
|
|
{
|
|
public:
|
|
static const intmax_t value = 0;
|
|
};
|
|
|
|
template <intmax_t X>
|
|
class __ll_mul<X, 0>
|
|
{
|
|
public:
|
|
static const intmax_t value = 0;
|
|
};
|
|
|
|
template <>
|
|
class __ll_mul<0, 0>
|
|
{
|
|
public:
|
|
static const intmax_t value = 0;
|
|
};
|
|
|
|
<font color="#c80000">// Not actually used but left here in case needed in future maintenance</font>
|
|
template <intmax_t X, intmax_t Y>
|
|
class __ll_div
|
|
{
|
|
static const intmax_t nan = (1LL << (sizeof(intmax_t) * CHAR_BIT - 1));
|
|
static const intmax_t min = nan + 1;
|
|
static const intmax_t max = -min;
|
|
|
|
static char test1[X != nan];
|
|
static char test2[Y != nan];
|
|
static char test3[Y != 0];
|
|
<font color="#c80000">// static_assert(X != nan && Y != nan && Y != 0, "overflow in __ll_div");</font>
|
|
public:
|
|
static const intmax_t value = X / Y;
|
|
};
|
|
|
|
template <intmax_t N, intmax_t D = 1>
|
|
class ratio
|
|
{
|
|
static char test1[__static_abs<N>::value >= 0];
|
|
static char test2[__static_abs<D>::value > 0];
|
|
<font color="#c80000">// static_assert(__static_abs<N>::value >= 0, "ratio numerator is out of range");</font>
|
|
<font color="#c80000">// static_assert(D != 0, "ratio divide by 0");</font>
|
|
<font color="#c80000">// static_assert(__static_abs<D>::value > 0, "ratio denominator is out of range");</font>
|
|
static const intmax_t __na = __static_abs<N>::value;
|
|
static const intmax_t __da = __static_abs<D>::value;
|
|
static const intmax_t __s = __static_sign<N>::value * __static_sign<D>::value;
|
|
static const intmax_t __gcd = __static_gcd<__na, __da>::value;
|
|
public:
|
|
static const intmax_t num = __s * __na / __gcd;
|
|
static const intmax_t den = __da / __gcd;
|
|
};
|
|
|
|
template <class T> struct ___is_ratio : tmp::false_type {};
|
|
template <intmax_t N, intmax_t D> struct ___is_ratio<ratio<N, D> > : tmp::true_type {};
|
|
template <class T> struct __is_ratio : ___is_ratio<typename tmp::remove_cv<T>::type> {};
|
|
|
|
typedef ratio<1LL, 1000000000000000000LL> atto;
|
|
typedef ratio<1LL, 1000000000000000LL> femto;
|
|
typedef ratio<1LL, 1000000000000LL> pico;
|
|
typedef ratio<1LL, 1000000000LL> nano;
|
|
typedef ratio<1LL, 1000000LL> micro;
|
|
typedef ratio<1LL, 1000LL> milli;
|
|
typedef ratio<1LL, 100LL> centi;
|
|
typedef ratio<1LL, 10LL> deci;
|
|
typedef ratio< 10LL, 1LL> deca;
|
|
typedef ratio< 100LL, 1LL> hecto;
|
|
typedef ratio< 1000LL, 1LL> kilo;
|
|
typedef ratio< 1000000LL, 1LL> mega;
|
|
typedef ratio< 1000000000LL, 1LL> giga;
|
|
typedef ratio< 1000000000000LL, 1LL> tera;
|
|
typedef ratio< 1000000000000000LL, 1LL> peta;
|
|
typedef ratio<1000000000000000000LL, 1LL> exa;
|
|
|
|
template <class R1, class R2>
|
|
struct ratio_add
|
|
{
|
|
typedef ratio<__ll_add<__ll_mul<R1::num, R2::den>::value,
|
|
__ll_mul<R1::den, R2::num>::value>::value,
|
|
__ll_mul<R1::den, R2::den>::value> type;
|
|
};
|
|
|
|
template <class R1, class R2>
|
|
struct ratio_subtract
|
|
{
|
|
typedef ratio<__ll_sub<__ll_mul<R1::num, R2::den>::value,
|
|
__ll_mul<R1::den, R2::num>::value>::value,
|
|
__ll_mul<R1::den, R2::den>::value> type;
|
|
};
|
|
|
|
template <class R1, class R2>
|
|
struct ratio_multiply
|
|
{
|
|
typedef ratio<__ll_mul<R1::num, R2::num>::value, __ll_mul<R1::den, R2::den>::value> type;
|
|
};
|
|
|
|
template <class R1, class R2>
|
|
struct ratio_divide
|
|
{
|
|
typedef ratio<__ll_mul<R1::num, R2::den>::value, __ll_mul<R1::den, R2::num>::value> type;
|
|
};
|
|
|
|
<font color="#c80000">// ratio_equal</font>
|
|
|
|
template <class R1, class R2>
|
|
struct ratio_equal
|
|
: public tmp::integral_constant<bool, R1::num == R2::num && R1::den == R2::den> {};
|
|
|
|
template <class R1, class R2>
|
|
struct ratio_not_equal
|
|
: public tmp::integral_constant<bool, !ratio_equal<R1, R2>::value> {};
|
|
|
|
<font color="#c80000">// ratio_less</font>
|
|
|
|
<font color="#c80000">// Protect against overflow, and still get the right answer as much as possible.</font>
|
|
<font color="#c80000">// This just demonstrates for fun how far you can push things without hitting</font>
|
|
<font color="#c80000">// overflow. The obvious and simple implementation is conforming.</font>
|
|
|
|
template <class R1, class R2, bool ok1, bool ok2>
|
|
struct __ratio_less3 <font color="#c80000">// true, true and false, false</font>
|
|
{
|
|
static const bool value = __ll_mul<R1::num, R2::den>::value < __ll_mul<R2::num, R1::den>::value;
|
|
};
|
|
|
|
template <class R1, class R2>
|
|
struct __ratio_less3<R1, R2, true, false>
|
|
{
|
|
static const bool value = true;
|
|
};
|
|
|
|
template <class R1, class R2>
|
|
struct __ratio_less3<R1, R2, false, true>
|
|
{
|
|
static const bool value = false;
|
|
};
|
|
|
|
template <class R1, class R2, bool = R1::num < R1::den == R2::num < R2::den>
|
|
struct __ratio_less2 <font color="#c80000">// N1 < D1 == N2 < D2</font>
|
|
{
|
|
static const intmax_t max = -((1LL << (sizeof(intmax_t) * CHAR_BIT - 1)) + 1);
|
|
static const bool ok1 = R1::num <= max / R2::den;
|
|
static const bool ok2 = R2::num <= max / R1::den;
|
|
static const bool value = __ratio_less3<R1, R2, ok1, ok2>::value;
|
|
};
|
|
|
|
template <class R1, class R2>
|
|
struct __ratio_less2<R1, R2, false> <font color="#c80000">// N1 < D1 != N2 < D2</font>
|
|
{
|
|
static const bool value = R1::num < R1::den;
|
|
};
|
|
|
|
template <class R1, class R2, bool = R1::num < R1::den == R2::num < R2::den>
|
|
struct __ratio_less1 <font color="#c80000">// N1 < D1 == N2 < D2</font>
|
|
{
|
|
static const bool value = __ratio_less2<ratio<R1::num, R2::num>, ratio<R1::den, R2::den> >::value;
|
|
};
|
|
|
|
template <class R1, class R2>
|
|
struct __ratio_less1<R1, R2, false> <font color="#c80000">// N1 < D1 != N2 < D2</font>
|
|
{
|
|
static const bool value = R1::num < R1::den;
|
|
};
|
|
|
|
template <class R1, class R2, intmax_t S1 = __static_sign<R1::num>::value,
|
|
intmax_t S2 = __static_sign<R2::num>::value>
|
|
struct __ratio_less
|
|
{
|
|
static const bool value = S1 < S2;
|
|
};
|
|
|
|
template <class R1, class R2>
|
|
struct __ratio_less<R1, R2, 1LL, 1LL>
|
|
{
|
|
static const bool value = __ratio_less1<R1, R2>::value;
|
|
};
|
|
|
|
template <class R1, class R2>
|
|
struct __ratio_less<R1, R2, -1LL, -1LL>
|
|
{
|
|
static const bool value = __ratio_less1<ratio<-R2::num, R2::den>, ratio<-R1::num, R1::den> >::value;
|
|
};
|
|
|
|
template <class R1, class R2>
|
|
struct ratio_less
|
|
: public tmp::integral_constant<bool, __ratio_less<R1, R2>::value> {};
|
|
|
|
template <class R1, class R2>
|
|
struct ratio_less_equal
|
|
: public tmp::integral_constant<bool, !ratio_less<R2, R1>::value> {};
|
|
|
|
template <class R1, class R2>
|
|
struct ratio_greater
|
|
: public tmp::integral_constant<bool, ratio_less<R2, R1>::value> {};
|
|
|
|
template <class R1, class R2>
|
|
struct ratio_greater_equal
|
|
: public tmp::integral_constant<bool, !ratio_less<R1, R2>::value> {};
|
|
|
|
template <class R1, class R2>
|
|
struct __ratio_gcd
|
|
{
|
|
typedef ratio<__static_gcd<R1::num, R2::num>::value,
|
|
__static_lcm<R1::den, R2::den>::value> type;
|
|
};
|
|
|
|
<font color="#c80000">//////////////////////////////////////////////////////////</font>
|
|
<font color="#c80000">////////////////////// duration //////////////////////////</font>
|
|
<font color="#c80000">//////////////////////////////////////////////////////////</font>
|
|
|
|
namespace datetime
|
|
{
|
|
|
|
template <class RepType, class Period = ratio<1> > class duration;
|
|
|
|
template <class T> struct ___is_duration : tmp::false_type {};
|
|
template <class Rep, class Period> struct ___is_duration<duration<Rep, Period> > : tmp::true_type {};
|
|
template <class T> struct __is_duration : ___is_duration<typename tmp::remove_cv<T>::type> {};
|
|
|
|
<font color="#c80000">// duration_cast</font>
|
|
|
|
<font color="#c80000">// duration_cast is the heart of this whole prototype. It can convert any</font>
|
|
<font color="#c80000">// duration to any other. It is also (implicitly) used in converting</font>
|
|
<font color="#c80000">// time_points. The conversion is always exact if possible. And it is</font>
|
|
<font color="#c80000">// always as efficient as hand written code. If different representations</font>
|
|
<font color="#c80000">// are involved, care is taken to never require implicit conversions.</font>
|
|
<font color="#c80000">// Instead static_cast is used explicitly for every required conversion.</font>
|
|
<font color="#c80000">// If there are a mixture of integral and floating point representations,</font>
|
|
<font color="#c80000">// the use of common_type ensures that the most logical "intermediate"</font>
|
|
<font color="#c80000">// representation is used.</font>
|
|
template <class FromDuration, class ToDuration,
|
|
class Period = typename ratio_divide<typename FromDuration::period, typename ToDuration::period>::type,
|
|
bool = Period::num == 1,
|
|
bool = Period::den == 1>
|
|
struct __duration_cast;
|
|
|
|
<font color="#c80000">// When the two periods are the same, all that is left to do is static_cast from</font>
|
|
<font color="#c80000">// the source representation to the target representation (which may be a no-op).</font>
|
|
<font color="#c80000">// This conversion is always exact as long as the static_cast from the source</font>
|
|
<font color="#c80000">// representation to the destination representation is exact.</font>
|
|
template <class FromDuration, class ToDuration, class Period>
|
|
struct __duration_cast<FromDuration, ToDuration, Period, true, true>
|
|
{
|
|
ToDuration operator()(const FromDuration& fd) const
|
|
{
|
|
return ToDuration(static_cast<typename ToDuration::rep>(fd.count()));
|
|
}
|
|
};
|
|
|
|
<font color="#c80000">// When the numerator of FromPeriod / ToPeriod is 1, then all we need to do is</font>
|
|
<font color="#c80000">// divide by the denominator of FromPeriod / ToPeriod. The common_type of</font>
|
|
<font color="#c80000">// the two representations is used for the intermediate computation before</font>
|
|
<font color="#c80000">// static_cast'ing to the destination.</font>
|
|
<font color="#c80000">// This conversion is generally not exact because of the division (but could be</font>
|
|
<font color="#c80000">// if you get lucky on the run time value of fd.count()).</font>
|
|
template <class FromDuration, class ToDuration, class Period>
|
|
struct __duration_cast<FromDuration, ToDuration, Period, true, false>
|
|
{
|
|
ToDuration operator()(const FromDuration& fd) const
|
|
{
|
|
#if VARIADIC_COMMON_TYPE == 0
|
|
typedef typename common_type<
|
|
typename common_type<typename ToDuration::rep, typename FromDuration::rep>::type,
|
|
intmax_t>::type C;
|
|
#else
|
|
typedef typename common_type<typename ToDuration::rep, typename FromDuration::rep, intmax_t>::type C;
|
|
#endif
|
|
return ToDuration(static_cast<typename ToDuration::rep>(
|
|
static_cast<C>(fd.count()) / static_cast<C>(Period::den)));
|
|
}
|
|
};
|
|
|
|
<font color="#c80000">// When the denomenator of FromPeriod / ToPeriod is 1, then all we need to do is</font>
|
|
<font color="#c80000">// multiply by the numerator of FromPeriod / ToPeriod. The common_type of</font>
|
|
<font color="#c80000">// the two representations is used for the intermediate computation before</font>
|
|
<font color="#c80000">// static_cast'ing to the destination.</font>
|
|
<font color="#c80000">// This conversion is always exact as long as the static_cast's involved are exact.</font>
|
|
template <class FromDuration, class ToDuration, class Period>
|
|
struct __duration_cast<FromDuration, ToDuration, Period, false, true>
|
|
{
|
|
ToDuration operator()(const FromDuration& fd) const
|
|
{
|
|
#if VARIADIC_COMMON_TYPE == 0
|
|
typedef typename common_type<
|
|
typename common_type<typename ToDuration::rep, typename FromDuration::rep>::type,
|
|
intmax_t>::type C;
|
|
#else
|
|
typedef typename common_type<typename ToDuration::rep, typename FromDuration::rep, intmax_t>::type C;
|
|
#endif
|
|
return ToDuration(static_cast<typename ToDuration::rep>(
|
|
static_cast<C>(fd.count()) * static_cast<C>(Period::num)));
|
|
}
|
|
};
|
|
|
|
<font color="#c80000">// When neither the numerator or denominator of FromPeriod / ToPeriod is 1, then we need to</font>
|
|
<font color="#c80000">// multiply by the numerator and divide by the denominator of FromPeriod / ToPeriod. The</font>
|
|
<font color="#c80000">// common_type of the two representations is used for the intermediate computation before</font>
|
|
<font color="#c80000">// static_cast'ing to the destination.</font>
|
|
<font color="#c80000">// This conversion is generally not exact because of the division (but could be</font>
|
|
<font color="#c80000">// if you get lucky on the run time value of fd.count()).</font>
|
|
template <class FromDuration, class ToDuration, class Period>
|
|
struct __duration_cast<FromDuration, ToDuration, Period, false, false>
|
|
{
|
|
ToDuration operator()(const FromDuration& fd) const
|
|
{
|
|
#if VARIADIC_COMMON_TYPE == 0
|
|
typedef typename common_type<
|
|
typename common_type<typename ToDuration::rep, typename FromDuration::rep>::type,
|
|
intmax_t>::type C;
|
|
#else
|
|
typedef typename common_type<typename ToDuration::rep, typename FromDuration::rep, intmax_t>::type C;
|
|
#endif
|
|
return ToDuration(static_cast<typename ToDuration::rep>(
|
|
static_cast<C>(fd.count()) * static_cast<C>(Period::num) / static_cast<C>(Period::den)));
|
|
}
|
|
};
|
|
|
|
<font color="#c80000">// Compile-time select the most efficient algorithm for the conversion...</font>
|
|
template <class ToDuration, class Rep, class Period>
|
|
inline
|
|
typename tmp::enable_if
|
|
<
|
|
__is_duration<ToDuration>::value,
|
|
ToDuration
|
|
>::type
|
|
duration_cast(const duration<Rep, Period>& fd)
|
|
{
|
|
return __duration_cast<duration<Rep, Period>, ToDuration>()(fd);
|
|
}
|
|
|
|
<font color="#c80000">// Support bidirectional (non-exact) conversions for floating point rep types</font>
|
|
<font color="#c80000">// (or user defined rep types which specialize treat_as_floating_point).</font>
|
|
template <class Rep> struct treat_as_floating_point : tmp::is_floating_point<Rep> {};
|
|
|
|
template <class Rep>
|
|
struct duration_values
|
|
{
|
|
static Rep __min_imp(tmp::false_type) {return -max();}
|
|
static Rep __min_imp(tmp::true_type) {return zero();}
|
|
public:
|
|
static Rep zero() {return Rep(0);}
|
|
static Rep max() {return numeric_limits<Rep>::max();}
|
|
static Rep min() {return __min_imp(tmp::is_unsigned<Rep>());}
|
|
};
|
|
|
|
<font color="#c80000">// duration</font>
|
|
|
|
template <class Rep, class Period>
|
|
class duration
|
|
{
|
|
static char test0[!__is_duration<Rep>::value];
|
|
<font color="#c80000">// static_assert(!__is_duration<Rep>::value, "A duration representation can not be a duration");</font>
|
|
static char test1[__is_ratio<Period>::value];
|
|
<font color="#c80000">// static_assert(__is_ratio<Period>::value, "Second template parameter of duration must be a std::ratio");</font>
|
|
static char test2[Period::num > 0];
|
|
<font color="#c80000">// static_assert(Period::num > 0, "duration period must be positive");</font>
|
|
public:
|
|
typedef Rep rep;
|
|
typedef Period period;
|
|
private:
|
|
rep rep_;
|
|
public:
|
|
|
|
duration() {} <font color="#c80000">// = default;</font>
|
|
template <class Rep2>
|
|
explicit duration(const Rep2& r,
|
|
typename tmp::enable_if
|
|
<
|
|
tmp::is_convertible<Rep2, rep>::value &&
|
|
(treat_as_floating_point<rep>::value ||
|
|
!treat_as_floating_point<rep>::value && !treat_as_floating_point<Rep2>::value)
|
|
>::type* = 0)
|
|
: rep_(r) {}
|
|
|
|
<font color="#c80000">// conversions</font>
|
|
template <class Rep2, class Period2>
|
|
duration(const duration<Rep2, Period2>& d,
|
|
typename tmp::enable_if
|
|
<
|
|
treat_as_floating_point<rep>::value ||
|
|
(ratio_divide<Period2, period>::type::den == 1 && !treat_as_floating_point<Rep2>::value)
|
|
>::type* = 0)
|
|
: rep_(duration_cast<duration>(d).count()) {}
|
|
|
|
<font color="#c80000">// observer</font>
|
|
|
|
rep count() const {return rep_;}
|
|
|
|
<font color="#c80000">// arithmetic</font>
|
|
|
|
duration operator+() const {return *this;}
|
|
duration operator-() const {return duration(-rep_);}
|
|
duration& operator++() {++rep_; return *this;}
|
|
duration operator++(int) {return duration(rep_++);}
|
|
duration& operator--() {--rep_; return *this;}
|
|
duration operator--(int) {return duration(rep_--);}
|
|
|
|
duration& operator+=(const duration& d) {rep_ += d.count(); return *this;}
|
|
duration& operator-=(const duration& d) {rep_ -= d.count(); return *this;}
|
|
|
|
duration& operator*=(const rep& rhs) {rep_ *= rhs; return *this;}
|
|
duration& operator/=(const rep& rhs) {rep_ /= rhs; return *this;}
|
|
|
|
<font color="#c80000">// special values</font>
|
|
|
|
static duration zero() {return duration(duration_values<rep>::zero());}
|
|
static duration min() {return duration(duration_values<rep>::min());}
|
|
static duration max() {return duration(duration_values<rep>::max());}
|
|
};
|
|
|
|
typedef duration<long long, nano> nanoseconds;
|
|
typedef duration<long long, micro> microseconds;
|
|
typedef duration<long long, milli> milliseconds;
|
|
typedef duration<long long > seconds;
|
|
typedef duration< long, ratio< 60> > minutes;
|
|
typedef duration< long, ratio<3600> > hours;
|
|
|
|
} <font color="#c80000">// datetime</font>
|
|
|
|
template <class Rep1, class Period1, class Rep2, class Period2>
|
|
struct common_type<datetime::duration<Rep1, Period1>, datetime::duration<Rep2, Period2> >
|
|
{
|
|
typedef datetime::duration<typename common_type<Rep1, Rep2>::type,
|
|
typename __ratio_gcd<Period1, Period2>::type> type;
|
|
};
|
|
|
|
namespace datetime {
|
|
|
|
<font color="#c80000">// Duration ==</font>
|
|
|
|
template <class LhsDuration, class RhsDuration>
|
|
struct __duration_eq
|
|
{
|
|
bool operator()(const LhsDuration& lhs, const RhsDuration& rhs)
|
|
{
|
|
typedef typename common_type<LhsDuration, RhsDuration>::type CD;
|
|
return CD(lhs).count() == CD(rhs).count();
|
|
}
|
|
};
|
|
|
|
template <class LhsDuration>
|
|
struct __duration_eq<LhsDuration, LhsDuration>
|
|
{
|
|
bool operator()(const LhsDuration& lhs, const LhsDuration& rhs)
|
|
{return lhs.count() == rhs.count();}
|
|
};
|
|
|
|
template <class Rep1, class Period1, class Rep2, class Period2>
|
|
inline
|
|
bool
|
|
operator==(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs)
|
|
{
|
|
return __duration_eq<duration<Rep1, Period1>, duration<Rep2, Period2> >()(lhs, rhs);
|
|
}
|
|
|
|
<font color="#c80000">// Duration !=</font>
|
|
|
|
template <class Rep1, class Period1, class Rep2, class Period2>
|
|
inline
|
|
bool
|
|
operator!=(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs)
|
|
{
|
|
return !(lhs == rhs);
|
|
}
|
|
|
|
<font color="#c80000">// Duration <</font>
|
|
|
|
template <class LhsDuration, class RhsDuration>
|
|
struct __duration_lt
|
|
{
|
|
bool operator()(const LhsDuration& lhs, const RhsDuration& rhs)
|
|
{
|
|
typedef typename common_type<LhsDuration, RhsDuration>::type CD;
|
|
return CD(lhs).count() < CD(rhs).count();
|
|
}
|
|
};
|
|
|
|
template <class LhsDuration>
|
|
struct __duration_lt<LhsDuration, LhsDuration>
|
|
{
|
|
bool operator()(const LhsDuration& lhs, const LhsDuration& rhs)
|
|
{return lhs.count() < rhs.count();}
|
|
};
|
|
|
|
template <class Rep1, class Period1, class Rep2, class Period2>
|
|
inline
|
|
bool
|
|
operator< (const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs)
|
|
{
|
|
return __duration_lt<duration<Rep1, Period1>, duration<Rep2, Period2> >()(lhs, rhs);
|
|
}
|
|
|
|
<font color="#c80000">// Duration ></font>
|
|
|
|
template <class Rep1, class Period1, class Rep2, class Period2>
|
|
inline
|
|
bool
|
|
operator> (const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs)
|
|
{
|
|
return rhs < lhs;
|
|
}
|
|
|
|
<font color="#c80000">// Duration <=</font>
|
|
|
|
template <class Rep1, class Period1, class Rep2, class Period2>
|
|
inline
|
|
bool
|
|
operator<=(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs)
|
|
{
|
|
return !(rhs < lhs);
|
|
}
|
|
|
|
<font color="#c80000">// Duration >=</font>
|
|
|
|
template <class Rep1, class Period1, class Rep2, class Period2>
|
|
inline
|
|
bool
|
|
operator>=(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs)
|
|
{
|
|
return !(lhs < rhs);
|
|
}
|
|
|
|
<font color="#c80000">// Duration +</font>
|
|
|
|
template <class Rep1, class Period1, class Rep2, class Period2>
|
|
inline
|
|
typename common_type<duration<Rep1, Period1>, duration<Rep2, Period2> >::type
|
|
operator+(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs)
|
|
{
|
|
typename common_type<duration<Rep1, Period1>, duration<Rep2, Period2> >::type result = lhs;
|
|
result += rhs;
|
|
return result;
|
|
}
|
|
|
|
<font color="#c80000">// Duration -</font>
|
|
|
|
template <class Rep1, class Period1, class Rep2, class Period2>
|
|
inline
|
|
typename common_type<duration<Rep1, Period1>, duration<Rep2, Period2> >::type
|
|
operator-(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs)
|
|
{
|
|
typename common_type<duration<Rep1, Period1>, duration<Rep2, Period2> >::type result = lhs;
|
|
result -= rhs;
|
|
return result;
|
|
}
|
|
|
|
<font color="#c80000">// Duration *</font>
|
|
|
|
template <class Rep1, class Period, class Rep2>
|
|
inline
|
|
typename tmp::enable_if
|
|
<
|
|
tmp::is_convertible<Rep1, typename common_type<Rep1, Rep2>::type>::value &&
|
|
tmp::is_convertible<Rep2, typename common_type<Rep1, Rep2>::type>::value,
|
|
duration<typename common_type<Rep1, Rep2>::type, Period>
|
|
>::type
|
|
operator*(const duration<Rep1, Period>& d, const Rep2& s)
|
|
{
|
|
typedef typename common_type<Rep1, Rep2>::type CR;
|
|
duration<CR, Period> r = d;
|
|
r *= static_cast<CR>(s);
|
|
return r;
|
|
}
|
|
|
|
template <class Rep1, class Period, class Rep2>
|
|
inline
|
|
typename tmp::enable_if
|
|
<
|
|
tmp::is_convertible<Rep1, typename common_type<Rep1, Rep2>::type>::value &&
|
|
tmp::is_convertible<Rep2, typename common_type<Rep1, Rep2>::type>::value,
|
|
duration<typename common_type<Rep1, Rep2>::type, Period>
|
|
>::type
|
|
operator*(const Rep1& s, const duration<Rep2, Period>& d)
|
|
{
|
|
return d * s;
|
|
}
|
|
|
|
<font color="#c80000">// Duration /</font>
|
|
|
|
template <class Duration, class Rep, bool = __is_duration<Rep>::value>
|
|
struct __duration_divide_result
|
|
{
|
|
};
|
|
|
|
template <class Duration, class Rep2,
|
|
bool = tmp::is_convertible<typename Duration::rep,
|
|
typename common_type<typename Duration::rep, Rep2>::type>::value &&
|
|
tmp::is_convertible<Rep2,
|
|
typename common_type<typename Duration::rep, Rep2>::type>::value>
|
|
struct __duration_divide_imp
|
|
{
|
|
};
|
|
|
|
template <class Rep1, class Period, class Rep2>
|
|
struct __duration_divide_imp<duration<Rep1, Period>, Rep2, true>
|
|
{
|
|
typedef duration<typename common_type<Rep1, Rep2>::type, Period> type;
|
|
};
|
|
|
|
template <class Rep1, class Period, class Rep2>
|
|
struct __duration_divide_result<duration<Rep1, Period>, Rep2, false>
|
|
: __duration_divide_imp<duration<Rep1, Period>, Rep2>
|
|
{
|
|
};
|
|
|
|
template <class Rep1, class Period, class Rep2>
|
|
inline
|
|
typename __duration_divide_result<duration<Rep1, Period>, Rep2>::type
|
|
operator/(const duration<Rep1, Period>& d, const Rep2& s)
|
|
{
|
|
typedef typename common_type<Rep1, Rep2>::type CR;
|
|
duration<CR, Period> r = d;
|
|
r /= static_cast<CR>(s);
|
|
return r;
|
|
}
|
|
|
|
template <class Rep1, class Period1, class Rep2, class Period2>
|
|
inline
|
|
typename common_type<Rep1, Rep2>::type
|
|
operator/(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs)
|
|
{
|
|
typedef typename common_type<duration<Rep1, Period1>, duration<Rep2, Period2> >::type CD;
|
|
return CD(lhs).count() / CD(rhs).count();
|
|
}
|
|
|
|
<font color="#c80000">//////////////////////////////////////////////////////////</font>
|
|
<font color="#c80000">///////////////////// time_point /////////////////////////</font>
|
|
<font color="#c80000">//////////////////////////////////////////////////////////</font>
|
|
|
|
template <class Clock, class Duration = typename Clock::duration>
|
|
class time_point
|
|
{
|
|
static char test1[__is_duration<Duration>::value];
|
|
<font color="#c80000">// static_assert(__is_duration<Duration>::value,</font>
|
|
<font color="#c80000">// "Second template parameter of time_point must be a std::datetime::duration");</font>
|
|
public:
|
|
typedef Clock clock;
|
|
typedef Duration duration;
|
|
typedef typename duration::rep rep;
|
|
typedef typename duration::period period;
|
|
private:
|
|
duration d_;
|
|
|
|
public:
|
|
time_point() : d_(duration::zero()) {}
|
|
explicit time_point(const duration& d) : d_(d) {}
|
|
|
|
<font color="#c80000">// conversions</font>
|
|
template <class Duration2>
|
|
time_point(const time_point<clock, Duration2>& t,
|
|
typename tmp::enable_if
|
|
<
|
|
tmp::is_convertible<Duration2, duration>::value
|
|
>::type* = 0)
|
|
: d_(t.time_since_epoch()) {}
|
|
|
|
<font color="#c80000">// observer</font>
|
|
|
|
duration time_since_epoch() const {return d_;}
|
|
|
|
<font color="#c80000">// arithmetic</font>
|
|
|
|
time_point& operator+=(const duration& d) {d_ += d; return *this;}
|
|
time_point& operator-=(const duration& d) {d_ -= d; return *this;}
|
|
|
|
<font color="#c80000">// special values</font>
|
|
|
|
static time_point min() {return time_point(duration::min());}
|
|
static time_point max() {return time_point(duration::max());}
|
|
};
|
|
|
|
} <font color="#c80000">// datetime</font>
|
|
|
|
template <class Clock, class Duration1, class Duration2>
|
|
struct common_type<datetime::time_point<Clock, Duration1>, datetime::time_point<Clock, Duration2> >
|
|
{
|
|
typedef datetime::time_point<Clock, typename common_type<Duration1, Duration2>::type> type;
|
|
};
|
|
|
|
namespace datetime {
|
|
|
|
template <class ToDuration, class Clock, class Duration>
|
|
inline
|
|
time_point<Clock, ToDuration>
|
|
time_point_cast(const time_point<Clock, Duration>& t)
|
|
{
|
|
return time_point<Clock, ToDuration>(duration_cast<ToDuration>(t.time_since_epoch()));
|
|
}
|
|
|
|
<font color="#c80000">// time_point ==</font>
|
|
|
|
template <class Clock, class Duration1, class Duration2>
|
|
inline
|
|
bool
|
|
operator==(const time_point<Clock, Duration1>& lhs, const time_point<Clock, Duration2>& rhs)
|
|
{
|
|
return lhs.time_since_epoch() == rhs.time_since_epoch();
|
|
}
|
|
|
|
<font color="#c80000">// time_point !=</font>
|
|
|
|
template <class Clock, class Duration1, class Duration2>
|
|
inline
|
|
bool
|
|
operator!=(const time_point<Clock, Duration1>& lhs, const time_point<Clock, Duration2>& rhs)
|
|
{
|
|
return !(lhs == rhs);
|
|
}
|
|
|
|
<font color="#c80000">// time_point <</font>
|
|
|
|
template <class Clock, class Duration1, class Duration2>
|
|
inline
|
|
bool
|
|
operator<(const time_point<Clock, Duration1>& lhs, const time_point<Clock, Duration2>& rhs)
|
|
{
|
|
return lhs.time_since_epoch() < rhs.time_since_epoch();
|
|
}
|
|
|
|
<font color="#c80000">// time_point ></font>
|
|
|
|
template <class Clock, class Duration1, class Duration2>
|
|
inline
|
|
bool
|
|
operator>(const time_point<Clock, Duration1>& lhs, const time_point<Clock, Duration2>& rhs)
|
|
{
|
|
return rhs < lhs;
|
|
}
|
|
|
|
<font color="#c80000">// time_point <=</font>
|
|
|
|
template <class Clock, class Duration1, class Duration2>
|
|
inline
|
|
bool
|
|
operator<=(const time_point<Clock, Duration1>& lhs, const time_point<Clock, Duration2>& rhs)
|
|
{
|
|
return !(rhs < lhs);
|
|
}
|
|
|
|
<font color="#c80000">// time_point >=</font>
|
|
|
|
template <class Clock, class Duration1, class Duration2>
|
|
inline
|
|
bool
|
|
operator>=(const time_point<Clock, Duration1>& lhs, const time_point<Clock, Duration2>& rhs)
|
|
{
|
|
return !(lhs < rhs);
|
|
}
|
|
|
|
<font color="#c80000">// time_point operator+(time_point x, duration y);</font>
|
|
|
|
template <class Clock, class Duration1, class Rep2, class Period2>
|
|
inline
|
|
time_point<Clock, typename common_type<Duration1, duration<Rep2, Period2> >::type>
|
|
operator+(const time_point<Clock, Duration1>& lhs, const duration<Rep2, Period2>& rhs)
|
|
{
|
|
typedef time_point<Clock, typename common_type<Duration1, duration<Rep2, Period2> >::type> TimeResult;
|
|
TimeResult r(lhs);
|
|
r += rhs;
|
|
return r;
|
|
}
|
|
|
|
<font color="#c80000">// time_point operator+(duration x, time_point y);</font>
|
|
|
|
template <class Rep1, class Period1, class Clock, class Duration2>
|
|
inline
|
|
time_point<Clock, typename common_type<duration<Rep1, Period1>, Duration2>::type>
|
|
operator+(const duration<Rep1, Period1>& lhs, const time_point<Clock, Duration2>& rhs)
|
|
{
|
|
return rhs + lhs;
|
|
}
|
|
|
|
<font color="#c80000">// time_point operator-(time_point x, duration y);</font>
|
|
|
|
template <class Clock, class Duration1, class Rep2, class Period2>
|
|
inline
|
|
time_point<Clock, typename common_type<Duration1, duration<Rep2, Period2> >::type>
|
|
operator-(const time_point<Clock, Duration1>& lhs, const duration<Rep2, Period2>& rhs)
|
|
{
|
|
return lhs + (-rhs);
|
|
}
|
|
|
|
<font color="#c80000">// duration operator-(time_point x, time_point y);</font>
|
|
|
|
template <class Clock, class Duration1, class Duration2>
|
|
inline
|
|
typename common_type<Duration1, Duration2>::type
|
|
operator-(const time_point<Clock, Duration1>& lhs, const time_point<Clock, Duration2>& rhs)
|
|
{
|
|
return lhs.time_since_epoch() - rhs.time_since_epoch();
|
|
}
|
|
|
|
<font color="#c80000">//////////////////////////////////////////////////////////</font>
|
|
<font color="#c80000">/////////////////////// clocks ///////////////////////////</font>
|
|
<font color="#c80000">//////////////////////////////////////////////////////////</font>
|
|
|
|
<font color="#c80000">// If you're porting, clocks are the system-specific (non-portable) part.</font>
|
|
<font color="#c80000">// You'll need to know how to get the current time and implement that under now().</font>
|
|
<font color="#c80000">// You'll need to know what units (tick period) and representation makes the most</font>
|
|
<font color="#c80000">// sense for your clock and set those accordingly.</font>
|
|
<font color="#c80000">// If you know how to map this clock to time_t (perhaps your clock is std::time, which</font>
|
|
<font color="#c80000">// makes that trivial), then you can fill out system_clock's to_time_t() and from_time_t().</font>
|
|
|
|
class system_clock
|
|
{
|
|
public:
|
|
typedef microseconds duration;
|
|
typedef duration::rep rep;
|
|
typedef duration::period period;
|
|
typedef datetime::time_point<system_clock> time_point;
|
|
static const bool is_monotonic = false;
|
|
|
|
static time_point now();
|
|
static time_t to_time_t (const time_point& t);
|
|
static time_point from_time_t(time_t t);
|
|
};
|
|
|
|
class monotonic_clock
|
|
{
|
|
public:
|
|
typedef nanoseconds duration;
|
|
typedef duration::rep rep;
|
|
typedef duration::period period;
|
|
typedef datetime::time_point<monotonic_clock> time_point;
|
|
static const bool is_monotonic = true;
|
|
|
|
static time_point now();
|
|
};
|
|
|
|
typedef monotonic_clock high_resolution_clock;
|
|
|
|
} <font color="#c80000">// datetime</font>
|
|
} <font color="#c80000">// std</font>
|
|
|
|
<font color="#c80000">// clocks.cpp</font>
|
|
|
|
#include <sys/time.h> <font color="#c80000">//for gettimeofday and timeval</font>
|
|
#include <mach/mach_time.h> <font color="#c80000">// mach_absolute_time, mach_timebase_info_data_t</font>
|
|
|
|
namespace std {
|
|
namespace datetime {
|
|
|
|
<font color="#c80000">// system_clock</font>
|
|
|
|
<font color="#c80000">// gettimeofday is the most precise "system time" available on this platform.</font>
|
|
<font color="#c80000">// It returns the number of microseconds since New Years 1970 in a struct called timeval</font>
|
|
<font color="#c80000">// which has a field for seconds and a field for microseconds.</font>
|
|
<font color="#c80000">// Fill in the timeval and then convert that to the time_point</font>
|
|
system_clock::time_point
|
|
system_clock::now()
|
|
{
|
|
timeval tv;
|
|
gettimeofday(&tv, 0);
|
|
return time_point(seconds(tv.tv_sec) + microseconds(tv.tv_usec));
|
|
}
|
|
|
|
<font color="#c80000">// Take advantage of the fact that on this platform time_t is nothing but</font>
|
|
<font color="#c80000">// an integral count of seconds since New Years 1970 (same epoch as timeval).</font>
|
|
<font color="#c80000">// Just get the duration out of the time_point and truncate it to seconds.</font>
|
|
time_t
|
|
system_clock::to_time_t(const time_point& t)
|
|
{
|
|
return time_t(duration_cast<seconds>(t.time_since_epoch()).count());
|
|
}
|
|
|
|
<font color="#c80000">// Just turn the time_t into a count of seconds and construct a time_point with it.</font>
|
|
system_clock::time_point
|
|
system_clock::from_time_t(time_t t)
|
|
{
|
|
return system_clock::time_point(seconds(t));
|
|
}
|
|
|
|
<font color="#c80000">// monotonic_clock</font>
|
|
|
|
<font color="#c80000">// Note, in this implementation monotonic_clock and high_resolution_clock</font>
|
|
<font color="#c80000">// are the same clock. They are both based on mach_absolute_time().</font>
|
|
<font color="#c80000">// mach_absolute_time() * MachInfo.numer / MachInfo.denom is the number of</font>
|
|
<font color="#c80000">// nanoseconds since the computer booted up. MachInfo.numer and MachInfo.denom</font>
|
|
<font color="#c80000">// are run time constants supplied by the OS. This clock has no relationship</font>
|
|
<font color="#c80000">// to the Gregorian calendar. It's main use is as a high resolution timer.</font>
|
|
|
|
<font color="#c80000">// MachInfo.numer / MachInfo.denom is often 1 on the latest equipment. Specialize</font>
|
|
<font color="#c80000">// for that case as an optimization.</font>
|
|
static
|
|
monotonic_clock::rep
|
|
monotonic_simplified()
|
|
{
|
|
return mach_absolute_time();
|
|
}
|
|
|
|
static
|
|
double
|
|
compute_monotonic_factor()
|
|
{
|
|
mach_timebase_info_data_t MachInfo;
|
|
mach_timebase_info(&MachInfo);
|
|
return static_cast<double>(MachInfo.numer) / MachInfo.denom;
|
|
}
|
|
|
|
static
|
|
monotonic_clock::rep
|
|
monotonic_full()
|
|
{
|
|
static const double factor = compute_monotonic_factor();
|
|
return static_cast<monotonic_clock::rep>(mach_absolute_time() * factor);
|
|
}
|
|
|
|
typedef monotonic_clock::rep (*FP)();
|
|
|
|
static
|
|
FP
|
|
init_monotonic_clock()
|
|
{
|
|
mach_timebase_info_data_t MachInfo;
|
|
mach_timebase_info(&MachInfo);
|
|
if (MachInfo.numer == MachInfo.denom)
|
|
return &monotonic_simplified;
|
|
return &monotonic_full;
|
|
}
|
|
|
|
monotonic_clock::time_point
|
|
monotonic_clock::now()
|
|
{
|
|
static FP fp = init_monotonic_clock();
|
|
return time_point(duration(fp()));
|
|
}
|
|
|
|
<font color="#c80000">// clocks.cpp end</font>
|
|
|
|
} } <font color="#c80000">// std::datetime</font>
|
|
|
|
<font color="#c80000">//////////////////////////////////////////////////////////</font>
|
|
<font color="#c80000">///////////// simulated thread interface /////////////////</font>
|
|
<font color="#c80000">//////////////////////////////////////////////////////////</font>
|
|
|
|
#include <iostream>
|
|
|
|
namespace std {
|
|
|
|
void __print_time(datetime::system_clock::time_point t)
|
|
{
|
|
using namespace datetime;
|
|
time_t c_time = system_clock::to_time_t(t);
|
|
std::tm* tmptr = std::localtime(&c_time);
|
|
system_clock::duration d = t.time_since_epoch();
|
|
std::cout << tmptr->tm_hour << ':' << tmptr->tm_min << ':' << tmptr->tm_sec
|
|
<< '.' << (d - duration_cast<seconds>(d)).count();
|
|
}
|
|
|
|
namespace this_thread {
|
|
|
|
template <class Rep, class Period>
|
|
void sleep_for(const datetime::duration<Rep, Period>& d)
|
|
{
|
|
datetime::microseconds t = datetime::duration_cast<datetime::microseconds>(d);
|
|
if (t < d)
|
|
++t;
|
|
if (t > datetime::microseconds(0))
|
|
std::cout << "sleep_for " << t.count() << " microseconds\n";
|
|
}
|
|
|
|
template <class Clock, class Duration>
|
|
void sleep_until(const datetime::time_point<Clock, Duration>& t)
|
|
{
|
|
using namespace datetime;
|
|
typedef time_point<Clock, Duration> Time;
|
|
typedef system_clock::time_point SysTime;
|
|
if (t > Clock::now())
|
|
{
|
|
typedef typename common_type<typename Time::duration, typename SysTime::duration>::type D;
|
|
<font color="#c80000">/* auto */</font> D d = t - Clock::now();
|
|
microseconds us = duration_cast<microseconds>(d);
|
|
if (us < d)
|
|
++us;
|
|
SysTime st = system_clock::now() + us;
|
|
std::cout << "sleep_until ";
|
|
__print_time(st);
|
|
std::cout << " which is " << (st - system_clock::now()).count() << " microseconds away\n";
|
|
}
|
|
}
|
|
|
|
} <font color="#c80000">// this_thread</font>
|
|
|
|
struct mutex {};
|
|
|
|
struct timed_mutex
|
|
{
|
|
bool try_lock() {std::cout << "timed_mutex::try_lock()\n";}
|
|
|
|
template <class Rep, class Period>
|
|
bool try_lock_for(const datetime::duration<Rep, Period>& d)
|
|
{
|
|
datetime::microseconds t = datetime::duration_cast<datetime::microseconds>(d);
|
|
if (t <= datetime::microseconds(0))
|
|
return try_lock();
|
|
std::cout << "try_lock_for " << t.count() << " microseconds\n";
|
|
return true;
|
|
}
|
|
|
|
template <class Clock, class Duration>
|
|
bool try_lock_until(const datetime::time_point<Clock, Duration>& t)
|
|
{
|
|
using namespace datetime;
|
|
typedef time_point<Clock, Duration> Time;
|
|
typedef system_clock::time_point SysTime;
|
|
if (t <= Clock::now())
|
|
return try_lock();
|
|
typedef typename common_type<typename Time::duration, typename Clock::duration>::type D;
|
|
<font color="#c80000">/* auto */</font> D d = t - Clock::now();
|
|
microseconds us = duration_cast<microseconds>(d);
|
|
SysTime st = system_clock::now() + us;
|
|
std::cout << "try_lock_until ";
|
|
__print_time(st);
|
|
std::cout << " which is " << (st - system_clock::now()).count() << " microseconds away\n";
|
|
}
|
|
};
|
|
|
|
struct condition_variable
|
|
{
|
|
template <class Rep, class Period>
|
|
bool wait_for(mutex&, const datetime::duration<Rep, Period>& d)
|
|
{
|
|
datetime::microseconds t = datetime::duration_cast<datetime::microseconds>(d);
|
|
std::cout << "wait_for " << t.count() << " microseconds\n";
|
|
return true;
|
|
}
|
|
|
|
template <class Clock, class Duration>
|
|
bool wait_until(mutex&, const datetime::time_point<Clock, Duration>& t)
|
|
{
|
|
using namespace datetime;
|
|
typedef time_point<Clock, Duration> Time;
|
|
typedef system_clock::time_point SysTime;
|
|
if (t <= Clock::now())
|
|
return false;
|
|
typedef typename common_type<typename Time::duration, typename Clock::duration>::type D;
|
|
<font color="#c80000">/* auto */</font> D d = t - Clock::now();
|
|
microseconds us = duration_cast<microseconds>(d);
|
|
SysTime st = system_clock::now() + us;
|
|
std::cout << "wait_until ";
|
|
__print_time(st);
|
|
std::cout << " which is " << (st - system_clock::now()).count() << " microseconds away\n";
|
|
}
|
|
};
|
|
|
|
} <font color="#c80000">// std</font>
|
|
|
|
<font color="#c80000">//////////////////////////////////////////////////////////</font>
|
|
<font color="#c80000">/////////////////// End of implemetation ////////////////</font>
|
|
<font color="#c80000">//////////////////////////////////////////////////////////</font>
|
|
|
|
<font color="#c80000">//////////////////////////////////////////////////////////</font>
|
|
<font color="#c80000">//////////// Simple sleep and wait examples //////////////</font>
|
|
<font color="#c80000">//////////////////////////////////////////////////////////</font>
|
|
|
|
std::mutex m;
|
|
std::timed_mutex mut;
|
|
std::condition_variable cv;
|
|
|
|
void basic_examples()
|
|
{
|
|
std::cout << "Running basic examples\n";
|
|
using namespace std;
|
|
using namespace std::datetime;
|
|
system_clock::time_point time_limit = system_clock::now() + seconds(4) + milliseconds(500);
|
|
this_thread::sleep_for(seconds(3));
|
|
this_thread::sleep_for(nanoseconds(300));
|
|
this_thread::sleep_until(time_limit);
|
|
<font color="#c80000">// this_thread::sleep_for(time_limit); // desired compile-time error</font>
|
|
<font color="#c80000">// this_thread::sleep_until(seconds(3)); // desired compile-time error</font>
|
|
mut.try_lock_for(milliseconds(30));
|
|
mut.try_lock_until(time_limit);
|
|
<font color="#c80000">// mut.try_lock_for(time_limit); // desired compile-time error</font>
|
|
<font color="#c80000">// mut.try_lock_until(milliseconds(30)); // desired compile-time error</font>
|
|
cv.wait_for(m, minutes(1)); <font color="#c80000">// real code would put this in a loop</font>
|
|
cv.wait_until(m, time_limit); <font color="#c80000">// real code would put this in a loop</font>
|
|
<font color="#c80000">// For those who prefer floating point</font>
|
|
this_thread::sleep_for(duration<double>(0.25));
|
|
this_thread::sleep_until(system_clock::now() + duration<double>(1.5));
|
|
}
|
|
|
|
<font color="#c80000">//////////////////////////////////////////////////////////</font>
|
|
<font color="#c80000">//////////////////// User1 Example ///////////////////////</font>
|
|
<font color="#c80000">//////////////////////////////////////////////////////////</font>
|
|
|
|
namespace User1
|
|
{
|
|
<font color="#c80000">// Example type-safe "physics" code interoperating with std::datetime::duration types</font>
|
|
<font color="#c80000">// and taking advantage of the std::ratio infrastructure and design philosophy.</font>
|
|
|
|
<font color="#c80000">// length - mimics std::datetime::duration except restricts representation to double.</font>
|
|
<font color="#c80000">// Uses std::ratio facilities for length units conversions.</font>
|
|
|
|
template <class Ratio>
|
|
class length
|
|
{
|
|
public:
|
|
typedef Ratio ratio;
|
|
private:
|
|
double len_;
|
|
public:
|
|
|
|
length() : len_(1) {}
|
|
length(const double& len) : len_(len) {}
|
|
|
|
<font color="#c80000">// conversions</font>
|
|
template <class R>
|
|
length(const length<R>& d)
|
|
: len_(d.count() * std::ratio_divide<Ratio, R>::type::den /
|
|
std::ratio_divide<Ratio, R>::type::num) {}
|
|
|
|
<font color="#c80000">// observer</font>
|
|
|
|
double count() const {return len_;}
|
|
|
|
<font color="#c80000">// arithmetic</font>
|
|
|
|
length& operator+=(const length& d) {len_ += d.count(); return *this;}
|
|
length& operator-=(const length& d) {len_ -= d.count(); return *this;}
|
|
|
|
length operator+() const {return *this;}
|
|
length operator-() const {return length(-len_);}
|
|
|
|
length& operator*=(double rhs) {len_ *= rhs; return *this;}
|
|
length& operator/=(double rhs) {len_ /= rhs; return *this;}
|
|
};
|
|
|
|
<font color="#c80000">// Sparse sampling of length units</font>
|
|
typedef length<std::ratio<1> > meter; <font color="#c80000">// set meter as "unity"</font>
|
|
typedef length<std::centi> centimeter; <font color="#c80000">// 1/100 meter</font>
|
|
typedef length<std::kilo> kilometer; <font color="#c80000">// 1000 meters</font>
|
|
typedef length<std::ratio<254, 10000> > inch; <font color="#c80000">// 254/10000 meters</font>
|
|
<font color="#c80000">// length takes ratio instead of two integral types so that definitions can be made like so:</font>
|
|
typedef length<std::ratio_multiply<std::ratio<12>, inch::ratio>::type> foot; <font color="#c80000">// 12 inchs</font>
|
|
typedef length<std::ratio_multiply<std::ratio<5280>, foot::ratio>::type> mile; <font color="#c80000">// 5280 feet</font>
|
|
|
|
<font color="#c80000">// Need a floating point definition of seconds</font>
|
|
typedef std::datetime::duration<double> seconds; <font color="#c80000">// unity</font>
|
|
<font color="#c80000">// Demo of (scientific) support for sub-nanosecond resolutions</font>
|
|
typedef std::datetime::duration<double, std::pico> picosecond; <font color="#c80000">// 10^-12 seconds</font>
|
|
typedef std::datetime::duration<double, std::femto> femtosecond; <font color="#c80000">// 10^-15 seconds</font>
|
|
typedef std::datetime::duration<double, std::atto> attosecond; <font color="#c80000">// 10^-18 seconds</font>
|
|
|
|
<font color="#c80000">// A very brief proof-of-concept for SIUnits-like library</font>
|
|
<font color="#c80000">// Hard-wired to floating point seconds and meters, but accepts other units (shown in testUser1())</font>
|
|
template <class R1, class R2>
|
|
class quantity
|
|
{
|
|
double q_;
|
|
public:
|
|
quantity() : q_(1) {}
|
|
|
|
double get() const {return q_;}
|
|
void set(double q) {q_ = q;}
|
|
};
|
|
|
|
template <>
|
|
class quantity<std::ratio<1>, std::ratio<0> >
|
|
{
|
|
double q_;
|
|
public:
|
|
quantity() : q_(1) {}
|
|
quantity(seconds d) : q_(d.count()) {} <font color="#c80000">// note: only User1::seconds needed here</font>
|
|
|
|
double get() const {return q_;}
|
|
void set(double q) {q_ = q;}
|
|
};
|
|
|
|
template <>
|
|
class quantity<std::ratio<0>, std::ratio<1> >
|
|
{
|
|
double q_;
|
|
public:
|
|
quantity() : q_(1) {}
|
|
quantity(meter d) : q_(d.count()) {} <font color="#c80000">// note: only User1::meter needed here</font>
|
|
|
|
double get() const {return q_;}
|
|
void set(double q) {q_ = q;}
|
|
};
|
|
|
|
template <>
|
|
class quantity<std::ratio<0>, std::ratio<0> >
|
|
{
|
|
double q_;
|
|
public:
|
|
quantity() : q_(1) {}
|
|
quantity(double d) : q_(d) {}
|
|
|
|
double get() const {return q_;}
|
|
void set(double q) {q_ = q;}
|
|
};
|
|
|
|
<font color="#c80000">// Example SI-Units</font>
|
|
typedef quantity<std::ratio<0>, std::ratio<0> > Scalar;
|
|
typedef quantity<std::ratio<1>, std::ratio<0> > Time; <font color="#c80000">// second</font>
|
|
typedef quantity<std::ratio<0>, std::ratio<1> > Distance; <font color="#c80000">// meter</font>
|
|
typedef quantity<std::ratio<-1>, std::ratio<1> > Speed; <font color="#c80000">// meter/second</font>
|
|
typedef quantity<std::ratio<-2>, std::ratio<1> > Acceleration; <font color="#c80000">// meter/second^2</font>
|
|
|
|
template <class R1, class R2, class R3, class R4>
|
|
quantity<typename std::ratio_subtract<R1, R3>::type, typename std::ratio_subtract<R2, R4>::type>
|
|
operator/(const quantity<R1, R2>& x, const quantity<R3, R4>& y)
|
|
{
|
|
typedef quantity<typename std::ratio_subtract<R1, R3>::type, typename std::ratio_subtract<R2, R4>::type> R;
|
|
R r;
|
|
r.set(x.get() / y.get());
|
|
return r;
|
|
}
|
|
|
|
template <class R1, class R2, class R3, class R4>
|
|
quantity<typename std::ratio_add<R1, R3>::type, typename std::ratio_add<R2, R4>::type>
|
|
operator*(const quantity<R1, R2>& x, const quantity<R3, R4>& y)
|
|
{
|
|
typedef quantity<typename std::ratio_add<R1, R3>::type, typename std::ratio_add<R2, R4>::type> R;
|
|
R r;
|
|
r.set(x.get() * y.get());
|
|
return r;
|
|
}
|
|
|
|
template <class R1, class R2>
|
|
quantity<R1, R2>
|
|
operator+(const quantity<R1, R2>& x, const quantity<R1, R2>& y)
|
|
{
|
|
typedef quantity<R1, R2> R;
|
|
R r;
|
|
r.set(x.get() + y.get());
|
|
return r;
|
|
}
|
|
|
|
template <class R1, class R2>
|
|
quantity<R1, R2>
|
|
operator-(const quantity<R1, R2>& x, const quantity<R1, R2>& y)
|
|
{
|
|
typedef quantity<R1, R2> R;
|
|
R r;
|
|
r.set(x.get() - y.get());
|
|
return r;
|
|
}
|
|
|
|
<font color="#c80000">// Example type-safe physics function</font>
|
|
Distance
|
|
compute_distance(Speed v0, Time t, Acceleration a)
|
|
{
|
|
return v0 * t + Scalar(.5) * a * t * t; <font color="#c80000">// if a units mistake is made here it won't compile</font>
|
|
}
|
|
|
|
} <font color="#c80000">// User1</font>
|
|
|
|
#include <iostream>
|
|
|
|
<font color="#c80000">// Exercise example type-safe physics function and show interoperation</font>
|
|
<font color="#c80000">// of custom time durations (User1::seconds) and standard time durations (std::hours).</font>
|
|
<font color="#c80000">// Though input can be arbitrary (but type-safe) units, output is always in SI-units</font>
|
|
<font color="#c80000">// (a limitation of the simplified Units lib demoed here).</font>
|
|
void testUser1()
|
|
{
|
|
std::cout << "*************\n";
|
|
std::cout << "* testUser1 *\n";
|
|
std::cout << "*************\n";
|
|
User1::Distance d( User1::mile(110) );
|
|
User1::Time t( std::datetime::hours(2) );
|
|
User1::Speed s = d / t;
|
|
std::cout << "Speed = " << s.get() << " meters/sec\n";
|
|
User1::Acceleration a = User1::Distance( User1::foot(32.2) ) / User1::Time() / User1::Time();
|
|
std::cout << "Acceleration = " << a.get() << " meters/sec^2\n";
|
|
User1::Distance df = compute_distance(s, User1::Time( User1::seconds(0.5) ), a);
|
|
std::cout << "Distance = " << df.get() << " meters\n";
|
|
std::cout << "There are " << User1::mile::ratio::den << '/' << User1::mile::ratio::num << " miles/meter";
|
|
User1::meter mt = 1;
|
|
User1::mile mi = mt;
|
|
std::cout << " which is approximately " << mi.count() << '\n';
|
|
std::cout << "There are " << User1::mile::ratio::num << '/' << User1::mile::ratio::den << " meters/mile";
|
|
mi = 1;
|
|
mt = mi;
|
|
std::cout << " which is approximately " << mt.count() << '\n';
|
|
User1::attosecond as(1);
|
|
User1::seconds sec = as;
|
|
std::cout << "1 attosecond is " << sec.count() << " seconds\n";
|
|
std::cout << "sec = as; <font color="#c80000">// compiles\n";</font>
|
|
sec = User1::seconds(1);
|
|
as = sec;
|
|
std::cout << "1 second is " << as.count() << " attoseconds\n";
|
|
std::cout << "as = sec; <font color="#c80000">// compiles\n";</font>
|
|
std::cout << "\n";
|
|
}
|
|
|
|
<font color="#c80000">//////////////////////////////////////////////////////////</font>
|
|
<font color="#c80000">//////////////////// User2 Example ///////////////////////</font>
|
|
<font color="#c80000">//////////////////////////////////////////////////////////</font>
|
|
|
|
<font color="#c80000">// Demonstrate User2:</font>
|
|
<font color="#c80000">// A "saturating" signed integral type is developed. This type has +/- infinity and a nan</font>
|
|
<font color="#c80000">// (like IEEE floating point) but otherwise obeys signed integral arithmetic.</font>
|
|
<font color="#c80000">// This class is subsequently used as the rep in std::datetime::duration to demonstrate a</font>
|
|
<font color="#c80000">// duration class that does not silently ignore overflow.</font>
|
|
#include <ostream>
|
|
#include <stdexcept>
|
|
#include <climits>
|
|
|
|
namespace User2
|
|
{
|
|
|
|
template <class I>
|
|
class saturate
|
|
{
|
|
public:
|
|
typedef I int_type;
|
|
|
|
static const int_type nan = int_type(int_type(1) << (sizeof(int_type) * CHAR_BIT - 1));
|
|
static const int_type neg_inf = nan + 1;
|
|
static const int_type pos_inf = -neg_inf;
|
|
private:
|
|
int_type i_;
|
|
|
|
<font color="#c80000">// static_assert(std::is_integral<int_type>::value && std::is_signed<int_type>::value,</font>
|
|
<font color="#c80000">// "saturate only accepts signed integral types");</font>
|
|
<font color="#c80000">// static_assert(nan == -nan && neg_inf < pos_inf,</font>
|
|
<font color="#c80000">// "saturate assumes two's complement hardware for signed integrals");</font>
|
|
|
|
public:
|
|
saturate() : i_(nan) {}
|
|
explicit saturate(int_type i) : i_(i) {}
|
|
<font color="#c80000">// explicit</font>
|
|
operator int_type() const;
|
|
|
|
saturate& operator+=(saturate x);
|
|
saturate& operator-=(saturate x) {return *this += -x;}
|
|
saturate& operator*=(saturate x);
|
|
saturate& operator/=(saturate x);
|
|
saturate& operator%=(saturate x);
|
|
|
|
saturate operator- () const {return saturate(-i_);}
|
|
saturate& operator++() {*this += saturate(int_type(1)); return *this;}
|
|
saturate operator++(int) {saturate tmp(*this); ++(*this); return tmp;}
|
|
saturate& operator--() {*this -= saturate(int_type(1)); return *this;}
|
|
saturate operator--(int) {saturate tmp(*this); --(*this); return tmp;}
|
|
|
|
friend saturate operator+(saturate x, saturate y) {return x += y;}
|
|
friend saturate operator-(saturate x, saturate y) {return x -= y;}
|
|
friend saturate operator*(saturate x, saturate y) {return x *= y;}
|
|
friend saturate operator/(saturate x, saturate y) {return x /= y;}
|
|
friend saturate operator%(saturate x, saturate y) {return x %= y;}
|
|
|
|
friend bool operator==(saturate x, saturate y)
|
|
{
|
|
if (x.i_ == nan || y.i_ == nan)
|
|
return false;
|
|
return x.i_ == y.i_;
|
|
}
|
|
|
|
friend bool operator!=(saturate x, saturate y) {return !(x == y);}
|
|
|
|
friend bool operator<(saturate x, saturate y)
|
|
{
|
|
if (x.i_ == nan || y.i_ == nan)
|
|
return false;
|
|
return x.i_ < y.i_;
|
|
}
|
|
|
|
friend bool operator<=(saturate x, saturate y)
|
|
{
|
|
if (x.i_ == nan || y.i_ == nan)
|
|
return false;
|
|
return x.i_ <= y.i_;
|
|
}
|
|
|
|
friend bool operator>(saturate x, saturate y)
|
|
{
|
|
if (x.i_ == nan || y.i_ == nan)
|
|
return false;
|
|
return x.i_ > y.i_;
|
|
}
|
|
|
|
friend bool operator>=(saturate x, saturate y)
|
|
{
|
|
if (x.i_ == nan || y.i_ == nan)
|
|
return false;
|
|
return x.i_ >= y.i_;
|
|
}
|
|
|
|
friend std::ostream& operator<<(std::ostream& os, saturate s)
|
|
{
|
|
switch (s.i_)
|
|
{
|
|
case pos_inf:
|
|
return os << "inf";
|
|
case nan:
|
|
return os << "nan";
|
|
case neg_inf:
|
|
return os << "-inf";
|
|
};
|
|
return os << s.i_;
|
|
}
|
|
};
|
|
|
|
template <class I>
|
|
saturate<I>::operator int_type() const
|
|
{
|
|
switch (i_)
|
|
{
|
|
case nan:
|
|
case neg_inf:
|
|
case pos_inf:
|
|
throw std::out_of_range("saturate special value can not convert to int_type");
|
|
}
|
|
return i_;
|
|
}
|
|
|
|
template <class I>
|
|
saturate<I>&
|
|
saturate<I>::operator+=(saturate x)
|
|
{
|
|
switch (i_)
|
|
{
|
|
case pos_inf:
|
|
switch (x.i_)
|
|
{
|
|
case neg_inf:
|
|
case nan:
|
|
i_ = nan;
|
|
}
|
|
return *this;
|
|
case nan:
|
|
return *this;
|
|
case neg_inf:
|
|
switch (x.i_)
|
|
{
|
|
case pos_inf:
|
|
case nan:
|
|
i_ = nan;
|
|
}
|
|
return *this;
|
|
}
|
|
switch (x.i_)
|
|
{
|
|
case pos_inf:
|
|
case neg_inf:
|
|
case nan:
|
|
i_ = x.i_;
|
|
return *this;
|
|
}
|
|
if (x.i_ >= 0)
|
|
{
|
|
if (i_ < pos_inf - x.i_)
|
|
i_ += x.i_;
|
|
else
|
|
i_ = pos_inf;
|
|
return *this;
|
|
}
|
|
if (i_ > neg_inf - x.i_)
|
|
i_ += x.i_;
|
|
else
|
|
i_ = neg_inf;
|
|
return *this;
|
|
}
|
|
|
|
template <class I>
|
|
saturate<I>&
|
|
saturate<I>::operator*=(saturate x)
|
|
{
|
|
switch (i_)
|
|
{
|
|
case 0:
|
|
switch (x.i_)
|
|
{
|
|
case pos_inf:
|
|
case neg_inf:
|
|
case nan:
|
|
i_ = nan;
|
|
}
|
|
return *this;
|
|
case pos_inf:
|
|
switch (x.i_)
|
|
{
|
|
case nan:
|
|
case 0:
|
|
i_ = nan;
|
|
return *this;
|
|
}
|
|
if (x.i_ < 0)
|
|
i_ = neg_inf;
|
|
return *this;
|
|
case nan:
|
|
return *this;
|
|
case neg_inf:
|
|
switch (x.i_)
|
|
{
|
|
case nan:
|
|
case 0:
|
|
i_ = nan;
|
|
return *this;
|
|
}
|
|
if (x.i_ < 0)
|
|
i_ = pos_inf;
|
|
return *this;
|
|
}
|
|
switch (x.i_)
|
|
{
|
|
case 0:
|
|
i_ = 0;
|
|
return *this;
|
|
case nan:
|
|
i_ = nan;
|
|
return *this;
|
|
case pos_inf:
|
|
if (i_ < 0)
|
|
i_ = neg_inf;
|
|
else
|
|
i_ = pos_inf;
|
|
return *this;
|
|
case neg_inf:
|
|
if (i_ < 0)
|
|
i_ = pos_inf;
|
|
else
|
|
i_ = neg_inf;
|
|
return *this;
|
|
}
|
|
int s = (i_ < 0 ? -1 : 1) * (x.i_ < 0 ? -1 : 1);
|
|
i_ = i_ < 0 ? -i_ : i_;
|
|
int_type x_i_ = x.i_ < 0 ? -x.i_ : x.i_;
|
|
if (i_ <= pos_inf / x_i_)
|
|
i_ *= x_i_;
|
|
else
|
|
i_ = pos_inf;
|
|
i_ *= s;
|
|
return *this;
|
|
}
|
|
|
|
template <class I>
|
|
saturate<I>&
|
|
saturate<I>::operator/=(saturate x)
|
|
{
|
|
switch (x.i_)
|
|
{
|
|
case pos_inf:
|
|
case neg_inf:
|
|
switch (i_)
|
|
{
|
|
case pos_inf:
|
|
case neg_inf:
|
|
case nan:
|
|
i_ = nan;
|
|
break;
|
|
default:
|
|
i_ = 0;
|
|
break;
|
|
}
|
|
return *this;
|
|
case nan:
|
|
i_ = nan;
|
|
return *this;
|
|
case 0:
|
|
switch (i_)
|
|
{
|
|
case pos_inf:
|
|
case neg_inf:
|
|
case nan:
|
|
return *this;
|
|
case 0:
|
|
i_ = nan;
|
|
return *this;
|
|
}
|
|
if (i_ > 0)
|
|
i_ = pos_inf;
|
|
else
|
|
i_ = neg_inf;
|
|
return *this;
|
|
}
|
|
switch (i_)
|
|
{
|
|
case 0:
|
|
case nan:
|
|
return *this;
|
|
case pos_inf:
|
|
case neg_inf:
|
|
if (x.i_ < 0)
|
|
i_ = -i_;
|
|
return *this;
|
|
}
|
|
i_ /= x.i_;
|
|
return *this;
|
|
}
|
|
|
|
template <class I>
|
|
saturate<I>&
|
|
saturate<I>::operator%=(saturate x)
|
|
{
|
|
<font color="#c80000">// *this -= *this / x * x; // definition</font>
|
|
switch (x.i_)
|
|
{
|
|
case nan:
|
|
case neg_inf:
|
|
case 0:
|
|
case pos_inf:
|
|
i_ = nan;
|
|
return *this;
|
|
}
|
|
switch (i_)
|
|
{
|
|
case neg_inf:
|
|
case pos_inf:
|
|
i_ = nan;
|
|
case nan:
|
|
return *this;
|
|
}
|
|
i_ %= x.i_;
|
|
return *this;
|
|
}
|
|
|
|
<font color="#c80000">// Demo overflow-safe integral durations ranging from picoseconds resolution to millennium resolution</font>
|
|
typedef std::datetime::duration<saturate<long long>, std::pico > picoseconds;
|
|
typedef std::datetime::duration<saturate<long long>, std::nano > nanoseconds;
|
|
typedef std::datetime::duration<saturate<long long>, std::micro > microseconds;
|
|
typedef std::datetime::duration<saturate<long long>, std::milli > milliseconds;
|
|
typedef std::datetime::duration<saturate<long long> > seconds;
|
|
typedef std::datetime::duration<saturate<long long>, std::ratio< 60LL> > minutes;
|
|
typedef std::datetime::duration<saturate<long long>, std::ratio< 3600LL> > hours;
|
|
typedef std::datetime::duration<saturate<long long>, std::ratio< 86400LL> > days;
|
|
typedef std::datetime::duration<saturate<long long>, std::ratio< 31556952LL> > years;
|
|
typedef std::datetime::duration<saturate<long long>, std::ratio<31556952000LL> > millennium;
|
|
|
|
} <font color="#c80000">// User2</font>
|
|
|
|
<font color="#c80000">// Demonstrate custom promotion rules (needed only if there are no implicit conversions)</font>
|
|
namespace User2 { namespace detail {
|
|
|
|
template <class T1, class T2, bool = tmp::is_integral<T1>::value>
|
|
struct promote_helper;
|
|
|
|
template <class T1, class T2>
|
|
struct promote_helper<T1, saturate<T2>, true> <font color="#c80000">// integral</font>
|
|
{
|
|
typedef typename std::common_type<T1, T2>::type rep;
|
|
typedef User2::saturate<rep> type;
|
|
};
|
|
|
|
template <class T1, class T2>
|
|
struct promote_helper<T1, saturate<T2>, false> <font color="#c80000">// floating</font>
|
|
{
|
|
typedef T1 type;
|
|
};
|
|
|
|
} }
|
|
|
|
namespace std
|
|
{
|
|
|
|
template <class T1, class T2>
|
|
struct common_type<User2::saturate<T1>, User2::saturate<T2> >
|
|
{
|
|
typedef typename common_type<T1, T2>::type rep;
|
|
typedef User2::saturate<rep> type;
|
|
};
|
|
|
|
template <class T1, class T2>
|
|
struct common_type<T1, User2::saturate<T2> >
|
|
: User2::detail::promote_helper<T1, User2::saturate<T2> > {};
|
|
|
|
template <class T1, class T2>
|
|
struct common_type<User2::saturate<T1>, T2>
|
|
: User2::detail::promote_helper<T2, User2::saturate<T1> > {};
|
|
|
|
|
|
<font color="#c80000">// Demonstrate specialization of duration_values:</font>
|
|
|
|
namespace datetime {
|
|
|
|
template <class I>
|
|
struct duration_values<User2::saturate<I> >
|
|
{
|
|
typedef User2::saturate<I> Rep;
|
|
public:
|
|
static Rep zero() {return Rep(0);}
|
|
static Rep max() {return Rep(Rep::pos_inf-1);}
|
|
static Rep min() {return -max();}
|
|
};
|
|
|
|
}
|
|
|
|
}
|
|
|
|
#include <iostream>
|
|
|
|
void testUser2()
|
|
{
|
|
std::cout << "*************\n";
|
|
std::cout << "* testUser2 *\n";
|
|
std::cout << "*************\n";
|
|
using namespace User2;
|
|
typedef seconds::rep sat;
|
|
years yr(sat(100));
|
|
std::cout << "100 years expressed as years = " << yr.count() << '\n';
|
|
nanoseconds ns = yr;
|
|
std::cout << "100 years expressed as nanoseconds = " << ns.count() << '\n';
|
|
ns += yr;
|
|
std::cout << "200 years expressed as nanoseconds = " << ns.count() << '\n';
|
|
ns += yr;
|
|
std::cout << "300 years expressed as nanoseconds = " << ns.count() << '\n';
|
|
<font color="#c80000">// yr = ns; // does not compile</font>
|
|
std::cout << "yr = ns; <font color="#c80000">// does not compile\n";</font>
|
|
<font color="#c80000">// picoseconds ps1 = yr; // does not compile, compile-time overflow in ratio arithmetic</font>
|
|
std::cout << "ps = yr; <font color="#c80000">// does not compile\n";</font>
|
|
ns = yr;
|
|
picoseconds ps = ns;
|
|
std::cout << "100 years expressed as picoseconds = " << ps.count() << '\n';
|
|
ps = ns / sat(1000);
|
|
std::cout << "0.1 years expressed as picoseconds = " << ps.count() << '\n';
|
|
yr = years(sat(-200000000));
|
|
std::cout << "200 million years ago encoded in years: " << yr.count() << '\n';
|
|
days d = std::datetime::duration_cast<days>(yr);
|
|
std::cout << "200 million years ago encoded in days: " << d.count() << '\n';
|
|
millennium c = std::datetime::duration_cast<millennium>(yr);
|
|
std::cout << "200 million years ago encoded in millennium: " << c.count() << '\n';
|
|
std::cout << "Demonstrate \"uninitialized protection\" behavior:\n";
|
|
seconds sec;
|
|
for (++sec; sec < seconds(sat(10)); ++sec)
|
|
;
|
|
std::cout << sec.count() << '\n';
|
|
std::cout << "\n";
|
|
}
|
|
|
|
void testStdUser()
|
|
{
|
|
std::cout << "***************\n";
|
|
std::cout << "* testStdUser *\n";
|
|
std::cout << "***************\n";
|
|
using namespace std::datetime;
|
|
hours hr = hours(100);
|
|
std::cout << "100 hours expressed as hours = " << hr.count() << '\n';
|
|
nanoseconds ns = hr;
|
|
std::cout << "100 hours expressed as nanoseconds = " << ns.count() << '\n';
|
|
ns += hr;
|
|
std::cout << "200 hours expressed as nanoseconds = " << ns.count() << '\n';
|
|
ns += hr;
|
|
std::cout << "300 hours expressed as nanoseconds = " << ns.count() << '\n';
|
|
<font color="#c80000">// hr = ns; // does not compile</font>
|
|
std::cout << "hr = ns; <font color="#c80000">// does not compile\n";</font>
|
|
<font color="#c80000">// hr * ns; // does not compile</font>
|
|
std::cout << "hr * ns; <font color="#c80000">// does not compile\n";</font>
|
|
duration<double> fs(2.5);
|
|
std::cout << "duration<double> has count() = " << fs.count() << '\n';
|
|
<font color="#c80000">// seconds sec = fs; // does not compile</font>
|
|
std::cout << "seconds sec = duration<double> won't compile\n";
|
|
seconds sec = duration_cast<seconds>(fs);
|
|
std::cout << "seconds has count() = " << sec.count() << '\n';
|
|
std::cout << "\n";
|
|
}
|
|
|
|
<font color="#c80000">// timeval clock demo</font>
|
|
<font color="#c80000">// Demonstrate the use of a timeval-like struct to be used as the representation</font>
|
|
<font color="#c80000">// type for both duraiton and time_point.</font>
|
|
|
|
namespace timeval_demo
|
|
{
|
|
|
|
class xtime {
|
|
private:
|
|
long tv_sec;
|
|
long tv_usec;
|
|
|
|
void fixup() {
|
|
if (tv_usec < 0) {
|
|
tv_usec += 1000000;
|
|
--tv_sec;
|
|
}
|
|
}
|
|
|
|
public:
|
|
|
|
explicit xtime(long sec, long usec) {
|
|
tv_sec = sec;
|
|
tv_usec = usec;
|
|
if (tv_usec < 0 || tv_usec >= 1000000) {
|
|
tv_sec += tv_usec / 1000000;
|
|
tv_usec %= 1000000;
|
|
fixup();
|
|
}
|
|
}
|
|
|
|
explicit xtime(long long usec)
|
|
{
|
|
tv_usec = static_cast<long>(usec % 1000000);
|
|
tv_sec = static_cast<long>(usec / 1000000);
|
|
fixup();
|
|
}
|
|
|
|
<font color="#c80000">// explicit</font>
|
|
operator long long() const {return static_cast<long long>(tv_sec) * 1000000 + tv_usec;}
|
|
|
|
xtime& operator += (xtime rhs) {
|
|
tv_sec += rhs.tv_sec;
|
|
tv_usec += rhs.tv_usec;
|
|
if (tv_usec >= 1000000) {
|
|
tv_usec -= 1000000;
|
|
++tv_sec;
|
|
}
|
|
return *this;
|
|
}
|
|
|
|
xtime& operator -= (xtime rhs) {
|
|
tv_sec -= rhs.tv_sec;
|
|
tv_usec -= rhs.tv_usec;
|
|
fixup();
|
|
return *this;
|
|
}
|
|
|
|
xtime& operator %= (xtime rhs) {
|
|
long long t = tv_sec * 1000000 + tv_usec;
|
|
long long r = rhs.tv_sec * 1000000 + rhs.tv_usec;
|
|
t %= r;
|
|
tv_sec = t / 1000000;
|
|
tv_usec = t % 1000000;
|
|
fixup();
|
|
return *this;
|
|
}
|
|
|
|
friend xtime operator+(xtime x, xtime y) {return x += y;}
|
|
friend xtime operator-(xtime x, xtime y) {return x -= y;}
|
|
friend xtime operator%(xtime x, xtime y) {return x %= y;}
|
|
|
|
friend bool operator==(xtime x, xtime y)
|
|
{ return (x.tv_sec == y.tv_sec && x.tv_usec == y.tv_usec); }
|
|
|
|
friend bool operator<(xtime x, xtime y) {
|
|
if (x.tv_sec == y.tv_sec)
|
|
return (x.tv_usec < y.tv_usec);
|
|
return (x.tv_sec < y.tv_sec);
|
|
}
|
|
|
|
friend bool operator!=(xtime x, xtime y) { return !(x == y); }
|
|
friend bool operator> (xtime x, xtime y) { return y < x; }
|
|
friend bool operator<=(xtime x, xtime y) { return !(y < x); }
|
|
friend bool operator>=(xtime x, xtime y) { return !(x < y); }
|
|
|
|
friend std::ostream& operator<<(std::ostream& os, xtime x)
|
|
{return os << '{' << x.tv_sec << ',' << x.tv_usec << '}';}
|
|
};
|
|
|
|
class xtime_clock
|
|
{
|
|
public:
|
|
typedef xtime rep;
|
|
typedef std::micro period;
|
|
typedef std::datetime::duration<rep, period> duration;
|
|
typedef std::datetime::time_point<xtime_clock> time_point;
|
|
|
|
static time_point now();
|
|
};
|
|
|
|
xtime_clock::time_point
|
|
xtime_clock::now()
|
|
{
|
|
time_point t(duration(xtime(0)));
|
|
gettimeofday((timeval*)&t, 0);
|
|
return t;
|
|
}
|
|
|
|
void test_xtime_clock()
|
|
{
|
|
using namespace std::datetime;
|
|
std::cout << "timeval_demo system clock test\n";
|
|
std::cout << "sizeof xtime_clock::time_point = " << sizeof(xtime_clock::time_point) << '\n';
|
|
std::cout << "sizeof xtime_clock::duration = " << sizeof(xtime_clock::duration) << '\n';
|
|
std::cout << "sizeof xtime_clock::rep = " << sizeof(xtime_clock::rep) << '\n';
|
|
xtime_clock::duration delay(milliseconds(5));
|
|
xtime_clock::time_point start = xtime_clock::now();
|
|
while (xtime_clock::now() - start <= delay)
|
|
;
|
|
xtime_clock::time_point stop = xtime_clock::now();
|
|
xtime_clock::duration elapsed = stop - start;
|
|
std::cout << "paused " << nanoseconds(elapsed).count() << " nanoseconds\n";
|
|
}
|
|
|
|
} <font color="#c80000">// timeval_demo</font>
|
|
|
|
<font color="#c80000">// Handle duration with resolution not known until run time</font>
|
|
|
|
namespace runtime_resolution
|
|
{
|
|
|
|
class duration
|
|
{
|
|
public:
|
|
typedef long long rep;
|
|
private:
|
|
rep rep_;
|
|
|
|
static const double ticks_per_nanosecond;
|
|
|
|
public:
|
|
typedef std::datetime::duration<double, std::nano> tonanosec;
|
|
|
|
duration() {} <font color="#c80000">// = default;</font>
|
|
explicit duration(const rep& r) : rep_(r) {}
|
|
|
|
<font color="#c80000">// conversions</font>
|
|
explicit duration(const tonanosec& d)
|
|
: rep_(static_cast<rep>(d.count() * ticks_per_nanosecond)) {}
|
|
|
|
<font color="#c80000">// explicit</font>
|
|
operator tonanosec() const {return tonanosec(rep_/ticks_per_nanosecond);}
|
|
|
|
<font color="#c80000">// observer</font>
|
|
|
|
rep count() const {return rep_;}
|
|
|
|
<font color="#c80000">// arithmetic</font>
|
|
|
|
duration& operator+=(const duration& d) {rep_ += d.rep_; return *this;}
|
|
duration& operator-=(const duration& d) {rep_ += d.rep_; return *this;}
|
|
duration& operator*=(rep rhs) {rep_ *= rhs; return *this;}
|
|
duration& operator/=(rep rhs) {rep_ /= rhs; return *this;}
|
|
|
|
duration operator+() const {return *this;}
|
|
duration operator-() const {return duration(-rep_);}
|
|
duration& operator++() {++rep_; return *this;}
|
|
duration operator++(int) {return duration(rep_++);}
|
|
duration& operator--() {--rep_; return *this;}
|
|
duration operator--(int) {return duration(rep_--);}
|
|
|
|
friend duration operator+(duration x, duration y) {return x += y;}
|
|
friend duration operator-(duration x, duration y) {return x -= y;}
|
|
friend duration operator*(duration x, rep y) {return x *= y;}
|
|
friend duration operator*(rep x, duration y) {return y *= x;}
|
|
friend duration operator/(duration x, rep y) {return x /= y;}
|
|
|
|
friend bool operator==(duration x, duration y) {return x.rep_ == y.rep_;}
|
|
friend bool operator!=(duration x, duration y) {return !(x == y);}
|
|
friend bool operator< (duration x, duration y) {return x.rep_ < y.rep_;}
|
|
friend bool operator<=(duration x, duration y) {return !(y < x);}
|
|
friend bool operator> (duration x, duration y) {return y < x;}
|
|
friend bool operator>=(duration x, duration y) {return !(x < y);}
|
|
};
|
|
|
|
static
|
|
double
|
|
init_duration()
|
|
{
|
|
mach_timebase_info_data_t MachInfo;
|
|
mach_timebase_info(&MachInfo);
|
|
return static_cast<double>(MachInfo.denom) / MachInfo.numer;
|
|
}
|
|
|
|
const double duration::ticks_per_nanosecond = init_duration();
|
|
|
|
class clock;
|
|
|
|
class time_point
|
|
{
|
|
public:
|
|
typedef runtime_resolution::clock clock;
|
|
typedef long long rep;
|
|
private:
|
|
rep rep_;
|
|
|
|
|
|
rep count() const {return rep_;}
|
|
public:
|
|
|
|
time_point() : rep_(0) {}
|
|
explicit time_point(const duration& d)
|
|
: rep_(d.count()) {}
|
|
|
|
<font color="#c80000">// arithmetic</font>
|
|
|
|
time_point& operator+=(const duration& d) {rep_ += d.count(); return *this;}
|
|
time_point& operator-=(const duration& d) {rep_ -= d.count(); return *this;}
|
|
|
|
friend time_point operator+(time_point x, duration y) {return x += y;}
|
|
friend time_point operator+(duration x, time_point y) {return y += x;}
|
|
friend time_point operator-(time_point x, duration y) {return x -= y;}
|
|
friend duration operator-(time_point x, time_point y) {return duration(x.rep_ - y.rep_);}
|
|
};
|
|
|
|
class clock
|
|
{
|
|
public:
|
|
typedef duration::rep rep;
|
|
typedef runtime_resolution::duration duration;
|
|
typedef runtime_resolution::time_point time_point;
|
|
|
|
static time_point now() {return time_point(duration(mach_absolute_time()));}
|
|
};
|
|
|
|
void test()
|
|
{
|
|
using namespace std::datetime;
|
|
std::cout << "runtime_resolution test\n";
|
|
clock::duration delay(std::datetime::milliseconds(5));
|
|
clock::time_point start = clock::now();
|
|
while (clock::now() - start <= delay)
|
|
;
|
|
clock::time_point stop = clock::now();
|
|
clock::duration elapsed = stop - start;
|
|
std::cout << "paused " << nanoseconds(duration_cast<nanoseconds>(duration::tonanosec(elapsed))).count()
|
|
<< " nanoseconds\n";
|
|
}
|
|
|
|
} <font color="#c80000">// runtime_resolution</font>
|
|
|
|
<font color="#c80000">// miscellaneous tests and demos:</font>
|
|
|
|
#include <cassert>
|
|
#include <iostream>
|
|
|
|
using namespace std::datetime;
|
|
|
|
void physics_function(duration<double> d)
|
|
{
|
|
std::cout << "d = " << d.count() << '\n';
|
|
}
|
|
|
|
void drive_physics_function()
|
|
{
|
|
physics_function(nanoseconds(3));
|
|
physics_function(hours(3));
|
|
physics_function(duration<double>(2./3));
|
|
std::cout.precision(16);
|
|
physics_function( hours(3) + nanoseconds(-3) );
|
|
}
|
|
|
|
void test_range()
|
|
{
|
|
using namespace std::datetime;
|
|
hours h1 = hours(24 * ( 365 * 292 + 292/4));
|
|
nanoseconds n1 = h1 + nanoseconds(1);
|
|
nanoseconds delta = n1 - h1;
|
|
std::cout << "292 years of hours = " << h1.count() << "hr\n";
|
|
std::cout << "Add a nanosecond = " << n1.count() << "ns\n";
|
|
std::cout << "Find the difference = " << delta.count() << "ns\n";
|
|
}
|
|
|
|
void test_extended_range()
|
|
{
|
|
using namespace std::datetime;
|
|
hours h1 = hours(24 * ( 365 * 244000 + 244000/4));
|
|
<font color="#c80000">/*auto*/</font> microseconds u1 = h1 + microseconds(1);
|
|
<font color="#c80000">/*auto*/</font> microseconds delta = u1 - h1;
|
|
std::cout << "244,000 years of hours = " << h1.count() << "hr\n";
|
|
std::cout << "Add a microsecond = " << u1.count() << "us\n";
|
|
std::cout << "Find the difference = " << delta.count() << "us\n";
|
|
}
|
|
|
|
template <class Rep, class Period>
|
|
void inspect_duration(std::datetime::duration<Rep, Period> d, const std::string& name)
|
|
{
|
|
typedef std::datetime::duration<Rep, Period> Duration;
|
|
std::cout << "********* " << name << " *********\n";
|
|
std::cout << "The period of " << name << " is " << (double)Period::num/Period::den << " seconds.\n";
|
|
std::cout << "The frequency of " << name << " is " << (double)Period::den/Period::num << " Hz.\n";
|
|
std::cout << "The representation is ";
|
|
if (tmp::is_floating_point<Rep>::value)
|
|
{
|
|
std::cout << "floating point\n";
|
|
std::cout << "The precision is the most significant ";
|
|
std::cout << std::numeric_limits<Rep>::digits10 << " decimal digits.\n";
|
|
}
|
|
else if (tmp::is_integral<Rep>::value)
|
|
{
|
|
std::cout << "integral\n";
|
|
d = Duration(Rep(1));
|
|
std::datetime::duration<double> dsec = d;
|
|
std::cout << "The precision is " << dsec.count() << " seconds.\n";
|
|
}
|
|
else
|
|
{
|
|
std::cout << "a class type\n";
|
|
d = Duration(Rep(1));
|
|
std::datetime::duration<double> dsec = d;
|
|
std::cout << "The precision is " << dsec.count() << " seconds.\n";
|
|
}
|
|
d = Duration(std::numeric_limits<Rep>::max());
|
|
using namespace std::datetime;
|
|
using namespace std;
|
|
typedef duration<double, ratio_multiply<ratio<24*3652425,10000>, hours::period>::type> Years;
|
|
Years years = d;
|
|
std::cout << "The range is +/- " << years.count() << " years.\n";
|
|
std::cout << "sizeof(" << name << ") = " << sizeof(d) << '\n';
|
|
}
|
|
|
|
void inspect_all()
|
|
{
|
|
using namespace std::datetime;
|
|
std::cout.precision(6);
|
|
inspect_duration(nanoseconds(), "nanoseconds");
|
|
inspect_duration(microseconds(), "microseconds");
|
|
inspect_duration(milliseconds(), "milliseconds");
|
|
inspect_duration(seconds(), "seconds");
|
|
inspect_duration(minutes(), "minutes");
|
|
inspect_duration(hours(), "hours");
|
|
inspect_duration(duration<double>(), "duration<double>");
|
|
}
|
|
|
|
void test_milliseconds()
|
|
{
|
|
using namespace std::datetime;
|
|
milliseconds ms(250);
|
|
ms += milliseconds(1);
|
|
milliseconds ms2(150);
|
|
milliseconds msdiff = ms - ms2;
|
|
if (msdiff == milliseconds(101))
|
|
std::cout << "success\n";
|
|
else
|
|
std::cout << "failure: " << msdiff.count() << '\n';
|
|
}
|
|
|
|
using namespace std;
|
|
using namespace std::datetime;
|
|
|
|
<font color="#c80000">// Example round_up utility: converts d to To, rounding up for inexact conversions</font>
|
|
<font color="#c80000">// Being able to *easily* write this function is a major feature!</font>
|
|
template <class To, class Rep, class Period>
|
|
To
|
|
round_up(duration<Rep, Period> d)
|
|
{
|
|
To result = duration_cast<To>(d);
|
|
if (result < d)
|
|
++result;
|
|
return result;
|
|
}
|
|
|
|
<font color="#c80000">// demonstrate interaction with xtime-like facility:</font>
|
|
|
|
using namespace std::datetime;
|
|
|
|
struct xtime
|
|
{
|
|
long sec;
|
|
unsigned long usec;
|
|
};
|
|
|
|
template <class Rep, class Period>
|
|
xtime
|
|
to_xtime_truncate(duration<Rep, Period> d)
|
|
{
|
|
xtime xt;
|
|
xt.sec = duration_cast<seconds>(d).count();
|
|
xt.usec = duration_cast<microseconds>(d - seconds(xt.sec)).count();
|
|
return xt;
|
|
}
|
|
|
|
template <class Rep, class Period>
|
|
xtime
|
|
to_xtime_round_up(duration<Rep, Period> d)
|
|
{
|
|
xtime xt;
|
|
xt.sec = duration_cast<seconds>(d).count();
|
|
xt.usec = round_up<microseconds>(d - seconds(xt.sec)).count();
|
|
return xt;
|
|
}
|
|
|
|
microseconds
|
|
from_xtime(xtime xt)
|
|
{
|
|
return seconds(xt.sec) + microseconds(xt.usec);
|
|
}
|
|
|
|
void print(xtime xt)
|
|
{
|
|
cout << '{' << xt.sec << ',' << xt.usec << "}\n";
|
|
}
|
|
|
|
void test_with_xtime()
|
|
{
|
|
cout << "test_with_xtime\n";
|
|
xtime xt = to_xtime_truncate(seconds(3) + milliseconds(251));
|
|
print(xt);
|
|
milliseconds ms = duration_cast<milliseconds>(from_xtime(xt));
|
|
cout << ms.count() << " milliseconds\n";
|
|
xt = to_xtime_round_up(ms);
|
|
print(xt);
|
|
xt = to_xtime_truncate(seconds(3) + nanoseconds(999));
|
|
print(xt);
|
|
xt = to_xtime_round_up(seconds(3) + nanoseconds(999));
|
|
print(xt);
|
|
}
|
|
|
|
void test_system_clock()
|
|
{
|
|
cout << "system_clock test" << endl;
|
|
system_clock::duration delay = milliseconds(5);
|
|
system_clock::time_point start = system_clock::now();
|
|
while (system_clock::now() - start <= delay)
|
|
;
|
|
system_clock::time_point stop = system_clock::now();
|
|
system_clock::duration elapsed = stop - start;
|
|
cout << "paused " << nanoseconds(elapsed).count() << " nanoseconds\n";
|
|
start = system_clock::now();
|
|
stop = system_clock::now();
|
|
cout << "system_clock resolution estimate: " << nanoseconds(stop-start).count() << " nanoseconds\n";
|
|
}
|
|
|
|
void test_monotonic_clock()
|
|
{
|
|
cout << "monotonic_clock test" << endl;
|
|
monotonic_clock::duration delay = milliseconds(5);
|
|
monotonic_clock::time_point start = monotonic_clock::now();
|
|
while (monotonic_clock::now() - start <= delay)
|
|
;
|
|
monotonic_clock::time_point stop = monotonic_clock::now();
|
|
monotonic_clock::duration elapsed = stop - start;
|
|
cout << "paused " << nanoseconds(elapsed).count() << " nanoseconds\n";
|
|
start = monotonic_clock::now();
|
|
stop = monotonic_clock::now();
|
|
cout << "monotonic_clock resolution estimate: " << nanoseconds(stop-start).count() << " nanoseconds\n";
|
|
}
|
|
|
|
void test_hi_resolution_clock()
|
|
{
|
|
cout << "high_resolution_clock test" << endl;
|
|
high_resolution_clock::duration delay = milliseconds(5);
|
|
high_resolution_clock::time_point start = high_resolution_clock::now();
|
|
while (high_resolution_clock::now() - start <= delay)
|
|
;
|
|
high_resolution_clock::time_point stop = high_resolution_clock::now();
|
|
high_resolution_clock::duration elapsed = stop - start;
|
|
cout << "paused " << nanoseconds(elapsed).count() << " nanoseconds\n";
|
|
start = high_resolution_clock::now();
|
|
stop = high_resolution_clock::now();
|
|
cout << "high_resolution_clock resolution estimate: " << nanoseconds(stop-start).count() << " nanoseconds\n";
|
|
}
|
|
|
|
void test_mixed_clock()
|
|
{
|
|
cout << "mixed clock test" << endl;
|
|
high_resolution_clock::time_point hstart = high_resolution_clock::now();
|
|
cout << "Add 5 milliseconds to a high_resolution_clock::time_point\n";
|
|
monotonic_clock::time_point mend = hstart + milliseconds(5);
|
|
bool b = hstart == mend;
|
|
system_clock::time_point sstart = system_clock::now();
|
|
std::cout << "Subtracting system_clock::time_point from monotonic_clock::time_point doesn't compile\n";
|
|
<font color="#c80000">// mend - sstart; // doesn't compile</font>
|
|
cout << "subtract high_resolution_clock::time_point from monotonic_clock::time_point"
|
|
" and add that to a system_clock::time_point\n";
|
|
system_clock::time_point send = sstart + duration_cast<system_clock::duration>(mend - hstart);
|
|
cout << "subtract two system_clock::time_point's and output that in microseconds:\n";
|
|
microseconds ms = send - sstart;
|
|
cout << ms.count() << " microseconds\n";
|
|
}
|
|
|
|
void test_c_mapping()
|
|
{
|
|
cout << "C map test\n";
|
|
using namespace std::datetime;
|
|
system_clock::time_point t1 = system_clock::now();
|
|
std::time_t c_time = system_clock::to_time_t(t1);
|
|
std::tm* tmptr = std::localtime(&c_time);
|
|
std::cout << "It is now " << tmptr->tm_hour << ':' << tmptr->tm_min << ':' << tmptr->tm_sec << ' '
|
|
<< tmptr->tm_year + 1900 << '-' << tmptr->tm_mon + 1 << '-' << tmptr->tm_mday << '\n';
|
|
c_time = std::mktime(tmptr);
|
|
system_clock::time_point t2 = system_clock::from_time_t(c_time);
|
|
microseconds ms = t1 - t2;
|
|
std::cout << "Round-tripping through the C interface truncated the precision by " << ms.count() << " microseconds\n";
|
|
}
|
|
|
|
void test_duration_division()
|
|
{
|
|
cout << hours(3) / milliseconds(5) << '\n';
|
|
cout << milliseconds(5) / hours(3) << '\n';
|
|
cout << hours(1) / milliseconds(1) << '\n';
|
|
}
|
|
|
|
namespace I_dont_like_the_default_duration_behavior
|
|
{
|
|
|
|
<font color="#c80000">// Here's how you override the duration's default constructor to do anything you want (in this case zero)</font>
|
|
|
|
template <class R>
|
|
class zero_default
|
|
{
|
|
public:
|
|
typedef R rep;
|
|
|
|
private:
|
|
rep rep_;
|
|
public:
|
|
zero_default(rep i = 0) : rep_(i) {}
|
|
operator rep() const {return rep_;}
|
|
|
|
zero_default& operator+=(zero_default x) {rep_ += x.rep_; return *this;}
|
|
zero_default& operator-=(zero_default x) {rep_ -= x.rep_; return *this;}
|
|
zero_default& operator*=(zero_default x) {rep_ *= x.rep_; return *this;}
|
|
zero_default& operator/=(zero_default x) {rep_ /= x.rep_; return *this;}
|
|
|
|
zero_default operator+ () const {return *this;}
|
|
zero_default operator- () const {return zero_default(-rep_);}
|
|
zero_default& operator++() {++rep_; return *this;}
|
|
zero_default operator++(int) {return zero_default(rep_++);}
|
|
zero_default& operator--() {--rep_; return *this;}
|
|
zero_default operator--(int) {return zero_default(rep_--);}
|
|
|
|
friend zero_default operator+(zero_default x, zero_default y) {return x += y;}
|
|
friend zero_default operator-(zero_default x, zero_default y) {return x -= y;}
|
|
friend zero_default operator*(zero_default x, zero_default y) {return x *= y;}
|
|
friend zero_default operator/(zero_default x, zero_default y) {return x /= y;}
|
|
|
|
friend bool operator==(zero_default x, zero_default y) {return x.rep_ == y.rep_;}
|
|
friend bool operator!=(zero_default x, zero_default y) {return !(x == y);}
|
|
friend bool operator< (zero_default x, zero_default y) {return x.rep_ < y.rep_;}
|
|
friend bool operator<=(zero_default x, zero_default y) {return !(y < x);}
|
|
friend bool operator> (zero_default x, zero_default y) {return y < x;}
|
|
friend bool operator>=(zero_default x, zero_default y) {return !(x < y);}
|
|
};
|
|
|
|
typedef std::datetime::duration<zero_default<long long>, std::nano > nanoseconds;
|
|
typedef std::datetime::duration<zero_default<long long>, std::micro > microseconds;
|
|
typedef std::datetime::duration<zero_default<long long>, std::milli > milliseconds;
|
|
typedef std::datetime::duration<zero_default<long long> > seconds;
|
|
typedef std::datetime::duration<zero_default<long long>, std::ratio<60> > minutes;
|
|
typedef std::datetime::duration<zero_default<long long>, std::ratio<3600> > hours;
|
|
|
|
void test()
|
|
{
|
|
milliseconds ms;
|
|
cout << ms.count() << '\n';
|
|
}
|
|
|
|
} <font color="#c80000">// I_dont_like_the_default_duration_behavior</font>
|
|
|
|
<font color="#c80000">// Build a min for two time_points</font>
|
|
|
|
template <class Rep, class Period>
|
|
void
|
|
print_duration(ostream& os, duration<Rep, Period> d)
|
|
{
|
|
os << d.count() << " * " << Period::num << '/' << Period::den << " seconds\n";
|
|
}
|
|
|
|
<font color="#c80000">// Example min utility: returns the earliest time_point</font>
|
|
<font color="#c80000">// Being able to *easily* write this function is a major feature!</font>
|
|
template <class Clock, class Duration1, class Duration2>
|
|
inline
|
|
typename common_type<time_point<Clock, Duration1>, time_point<Clock, Duration2> >::type
|
|
min(time_point<Clock, Duration1> t1, time_point<Clock, Duration2> t2)
|
|
{
|
|
return t2 < t1 ? t2 : t1;
|
|
}
|
|
|
|
void test_min()
|
|
{
|
|
typedef time_point<system_clock, common_type<system_clock::duration, seconds>::type> T1;
|
|
typedef time_point<system_clock, common_type<system_clock::duration, nanoseconds>::type> T2;
|
|
typedef common_type<T1, T2>::type T3;
|
|
<font color="#c80000">/*auto*/</font> T1 t1 = system_clock::now() + seconds(3);
|
|
<font color="#c80000">/*auto*/</font> T2 t2 = system_clock::now() + nanoseconds(3);
|
|
<font color="#c80000">/*auto*/</font> T3 t3 = min(t1, t2);
|
|
print_duration(cout, t1 - t3);
|
|
print_duration(cout, t2 - t3);
|
|
}
|
|
|
|
void explore_limits()
|
|
{
|
|
typedef duration<long long, ratio_multiply<ratio<24*3652425,10000>, hours::period>::type> Years;
|
|
monotonic_clock::time_point t1( Years(250));
|
|
monotonic_clock::time_point t2(-Years(250));
|
|
<font color="#c80000">// nanosecond resolution is likely to overflow. "up cast" to microseconds.</font>
|
|
<font color="#c80000">// The "up cast" trades precision for range.</font>
|
|
microseconds d = time_point_cast<microseconds>(t1) - time_point_cast<microseconds>(t2);
|
|
cout << d.count() << " microseconds\n";
|
|
}
|
|
|
|
void manipulate_clock_object(system_clock clock)
|
|
{
|
|
system_clock::duration delay = milliseconds(5);
|
|
system_clock::time_point start = clock.now();
|
|
while (clock.now() - start <= delay)
|
|
;
|
|
system_clock::time_point stop = clock.now();
|
|
system_clock::duration elapsed = stop - start;
|
|
cout << "paused " << nanoseconds(elapsed).count() << " nanoseconds\n";
|
|
};
|
|
|
|
template <long long speed>
|
|
struct cycle_count
|
|
{
|
|
typedef typename ratio_multiply<ratio<speed>, mega>::type frequency; <font color="#c80000">// Mhz</font>
|
|
typedef typename ratio_divide<ratio<1>, frequency>::type period;
|
|
typedef long long rep;
|
|
typedef std::datetime::duration<rep, period> duration;
|
|
typedef std::datetime::time_point<cycle_count> time_point;
|
|
|
|
static time_point now()
|
|
{
|
|
static long long tick = 0;
|
|
<font color="#c80000">// return exact cycle count</font>
|
|
return time_point(duration(++tick)); <font color="#c80000">// fake access to clock cycle count</font>
|
|
}
|
|
};
|
|
|
|
template <long long speed>
|
|
struct approx_cycle_count
|
|
{
|
|
static const long long frequency = speed * 1000000; <font color="#c80000">// MHz</font>
|
|
typedef nanoseconds duration;
|
|
typedef duration::rep rep;
|
|
typedef duration::period period;
|
|
static const long long nanosec_per_sec = period::den;
|
|
typedef std::datetime::time_point<approx_cycle_count> time_point;
|
|
|
|
static time_point now()
|
|
{
|
|
static long long tick = 0;
|
|
<font color="#c80000">// return cycle count as an approximate number of nanoseconds</font>
|
|
<font color="#c80000">// compute as if nanoseconds is only duration in the std::lib</font>
|
|
return time_point(duration(++tick * nanosec_per_sec / frequency));
|
|
}
|
|
};
|
|
|
|
void cycle_count_delay()
|
|
{
|
|
{
|
|
typedef cycle_count<400> clock;
|
|
cout << "\nSimulated " << clock::frequency::num / mega::num << "MHz clock which has a tick period of "
|
|
<< duration<double, nano>(clock::duration(1)).count() << " nanoseconds\n";
|
|
nanoseconds delayns(500);
|
|
clock::duration delay = duration_cast<clock::duration>(delayns);
|
|
cout << "delay = " << delayns.count() << " nanoseconds which is " << delay.count() << " cycles\n";
|
|
clock::time_point start = clock::now();
|
|
clock::time_point stop = start + delay;
|
|
while (clock::now() < stop) <font color="#c80000">// no multiplies or divides in this loop</font>
|
|
;
|
|
clock::time_point end = clock::now();
|
|
clock::duration elapsed = end - start;
|
|
cout << "paused " << elapsed.count() << " cycles ";
|
|
cout << "which is " << duration_cast<nanoseconds>(elapsed).count() << " nanoseconds\n";
|
|
}
|
|
{
|
|
typedef approx_cycle_count<400> clock;
|
|
cout << "\nSimulated " << clock::frequency / 1000000 << "MHz clock modeled with nanoseconds\n";
|
|
clock::duration delay = nanoseconds(500);
|
|
cout << "delay = " << delay.count() << " nanoseconds\n";
|
|
clock::time_point start = clock::now();
|
|
clock::time_point stop = start + delay;
|
|
while (clock::now() < stop) <font color="#c80000">// 1 multiplication and 1 division in this loop</font>
|
|
;
|
|
clock::time_point end = clock::now();
|
|
clock::duration elapsed = end - start;
|
|
cout << "paused " << elapsed.count() << " nanoseconds\n";
|
|
}
|
|
{
|
|
typedef cycle_count<1500> clock;
|
|
cout << "\nSimulated " << clock::frequency::num / mega::num << "MHz clock which has a tick period of "
|
|
<< duration<double, nano>(clock::duration(1)).count() << " nanoseconds\n";
|
|
nanoseconds delayns(500);
|
|
clock::duration delay = duration_cast<clock::duration>(delayns);
|
|
cout << "delay = " << delayns.count() << " nanoseconds which is " << delay.count() << " cycles\n";
|
|
clock::time_point start = clock::now();
|
|
clock::time_point stop = start + delay;
|
|
while (clock::now() < stop) <font color="#c80000">// no multiplies or divides in this loop</font>
|
|
;
|
|
clock::time_point end = clock::now();
|
|
clock::duration elapsed = end - start;
|
|
cout << "paused " << elapsed.count() << " cycles ";
|
|
cout << "which is " << duration_cast<nanoseconds>(elapsed).count() << " nanoseconds\n";
|
|
}
|
|
{
|
|
typedef approx_cycle_count<1500> clock;
|
|
cout << "\nSimulated " << clock::frequency / 1000000 << "MHz clock modeled with nanoseconds\n";
|
|
clock::duration delay = nanoseconds(500);
|
|
cout << "delay = " << delay.count() << " nanoseconds\n";
|
|
clock::time_point start = clock::now();
|
|
clock::time_point stop = start + delay;
|
|
while (clock::now() < stop) <font color="#c80000">// 1 multiplication and 1 division in this loop</font>
|
|
;
|
|
clock::time_point end = clock::now();
|
|
clock::duration elapsed = end - start;
|
|
cout << "paused " << elapsed.count() << " nanoseconds\n";
|
|
}
|
|
}
|
|
|
|
void test_special_values()
|
|
{
|
|
std::cout << "duration<unsigned>::min().count() = " << duration<unsigned>::min().count() << '\n';
|
|
std::cout << "duration<unsigned>::zero().count() = " << duration<unsigned>::zero().count() << '\n';
|
|
std::cout << "duration<unsigned>::max().count() = " << duration<unsigned>::max().count() << '\n';
|
|
std::cout << "duration<int>::min().count() = " << duration<int>::min().count() << '\n';
|
|
std::cout << "duration<int>::zero().count() = " << duration<int>::zero().count() << '\n';
|
|
std::cout << "duration<int>::max().count() = " << duration<int>::max().count() << '\n';
|
|
}
|
|
|
|
int main()
|
|
{
|
|
basic_examples();
|
|
testStdUser();
|
|
testUser1();
|
|
testUser2();
|
|
drive_physics_function();
|
|
test_range();
|
|
test_extended_range();
|
|
inspect_all();
|
|
test_milliseconds();
|
|
test_with_xtime();
|
|
test_system_clock();
|
|
test_monotonic_clock();
|
|
test_hi_resolution_clock();
|
|
test_mixed_clock();
|
|
timeval_demo::test_xtime_clock();
|
|
runtime_resolution::test();
|
|
test_c_mapping();
|
|
test_duration_division();
|
|
I_dont_like_the_default_duration_behavior::test();
|
|
test_min();
|
|
#if VARIADIC_COMMON_TYPE
|
|
inspect_duration(common_type<duration<double>, hours, microseconds>::type(),
|
|
"common_type<duration<double>, hours, microseconds>::type");
|
|
#endif
|
|
explore_limits();
|
|
manipulate_clock_object(system_clock());
|
|
duration<double, milli> d = milliseconds(3) * 2.5;
|
|
inspect_duration(milliseconds(3) * 2.5, "milliseconds(3) * 2.5");
|
|
cout << d.count() << '\n';
|
|
<font color="#c80000">// milliseconds ms(3.5); // doesn't compile</font>
|
|
cout << "milliseconds ms(3.5) doesn't compile\n";
|
|
cycle_count_delay();
|
|
test_special_values();
|
|
}
|
|
|
|
<font color="#c80000">/*
|
|
Output
|
|
|
|
Running basic examples
|
|
sleep_for 3000000 microseconds
|
|
sleep_for 1 microseconds
|
|
sleep_until 10:47:17.728293 which is 4499340 microseconds away
|
|
try_lock_for 30000 microseconds
|
|
try_lock_until 10:47:17.728285 which is 4499303 microseconds away
|
|
wait_for 60000000 microseconds
|
|
wait_until 10:47:17.728285 which is 4499264 microseconds away
|
|
sleep_for 250000 microseconds
|
|
sleep_until 10:47:14.729077 which is 1499979 microseconds away
|
|
***************
|
|
* testStdUser *
|
|
***************
|
|
100 hours expressed as hours = 100
|
|
100 hours expressed as nanoseconds = 360000000000000
|
|
200 hours expressed as nanoseconds = 720000000000000
|
|
300 hours expressed as nanoseconds = 1080000000000000
|
|
hr = ns; <font color="#c80000">// does not compile</font>
|
|
hr * ns; <font color="#c80000">// does not compile</font>
|
|
duration<double> has count() = 2.5
|
|
seconds sec = duration<double> won't compile
|
|
seconds has count() = 2
|
|
|
|
*************
|
|
* testUser1 *
|
|
*************
|
|
Speed = 24.5872 meters/sec
|
|
Acceleration = 9.81456 meters/sec^2
|
|
Distance = 13.5204 meters
|
|
There are 125/201168 miles/meter which is approximately 0.000621371
|
|
There are 201168/125 meters/mile which is approximately 1609.34
|
|
1 attosecond is 1e-18 seconds
|
|
sec = as; <font color="#c80000">// compiles</font>
|
|
1 second is 1e+18 attoseconds
|
|
as = sec; <font color="#c80000">// compiles</font>
|
|
|
|
*************
|
|
* testUser2 *
|
|
*************
|
|
100 years expressed as years = 100
|
|
100 years expressed as nanoseconds = 3155695200000000000
|
|
200 years expressed as nanoseconds = 6311390400000000000
|
|
300 years expressed as nanoseconds = inf
|
|
yr = ns; <font color="#c80000">// does not compile</font>
|
|
ps = yr; <font color="#c80000">// does not compile</font>
|
|
100 years expressed as picoseconds = inf
|
|
0.1 years expressed as picoseconds = 3155695200000000000
|
|
200 million years ago encoded in years: -200000000
|
|
200 million years ago encoded in days: -73048500000
|
|
200 million years ago encoded in millennium: -200000
|
|
Demonstrate "uninitialized protection" behavior:
|
|
nan
|
|
|
|
d = 3e-09
|
|
d = 10800
|
|
d = 0.666667
|
|
d = 10799.999999997
|
|
292 years of hours = 2559672hr
|
|
Add a nanosecond = 9214819200000000001ns
|
|
Find the difference = 1ns
|
|
244,000 years of hours = 2138904000hr
|
|
Add a microsecond = 7700054400000000001us
|
|
Find the difference = 1us
|
|
********* nanoseconds *********
|
|
The period of nanoseconds is 1e-09 seconds.
|
|
The frequency of nanoseconds is 1e+09 Hz.
|
|
The representation is integral
|
|
The precision is 1e-09 seconds.
|
|
The range is +/- 292.277 years.
|
|
sizeof(nanoseconds) = 8
|
|
********* microseconds *********
|
|
The period of microseconds is 1e-06 seconds.
|
|
The frequency of microseconds is 1e+06 Hz.
|
|
The representation is integral
|
|
The precision is 1e-06 seconds.
|
|
The range is +/- 292277 years.
|
|
sizeof(microseconds) = 8
|
|
********* milliseconds *********
|
|
The period of milliseconds is 0.001 seconds.
|
|
The frequency of milliseconds is 1000 Hz.
|
|
The representation is integral
|
|
The precision is 0.001 seconds.
|
|
The range is +/- 2.92277e+08 years.
|
|
sizeof(milliseconds) = 8
|
|
********* seconds *********
|
|
The period of seconds is 1 seconds.
|
|
The frequency of seconds is 1 Hz.
|
|
The representation is integral
|
|
The precision is 1 seconds.
|
|
The range is +/- 2.92277e+11 years.
|
|
sizeof(seconds) = 8
|
|
********* minutes *********
|
|
The period of minutes is 60 seconds.
|
|
The frequency of minutes is 0.0166667 Hz.
|
|
The representation is integral
|
|
The precision is 60 seconds.
|
|
The range is +/- 4083.06 years.
|
|
sizeof(minutes) = 4
|
|
********* hours *********
|
|
The period of hours is 3600 seconds.
|
|
The frequency of hours is 0.000277778 Hz.
|
|
The representation is integral
|
|
The precision is 3600 seconds.
|
|
The range is +/- 244984 years.
|
|
sizeof(hours) = 4
|
|
********* duration<double> *********
|
|
The period of duration<double> is 1 seconds.
|
|
The frequency of duration<double> is 1 Hz.
|
|
The representation is floating point
|
|
The precision is the most significant 15 decimal digits.
|
|
The range is +/- 5.69666e+300 years.
|
|
sizeof(duration<double>) = 8
|
|
success
|
|
test_with_xtime
|
|
{3,251000}
|
|
3251 milliseconds
|
|
{3,251000}
|
|
{3,0}
|
|
{3,1}
|
|
system_clock test
|
|
paused 5001000 nanoseconds
|
|
system_clock resolution estimate: 0 nanoseconds
|
|
monotonic_clock test
|
|
paused 5000181 nanoseconds
|
|
monotonic_clock resolution estimate: 97 nanoseconds
|
|
high_resolution_clock test
|
|
paused 5000277 nanoseconds
|
|
high_resolution_clock resolution estimate: 96 nanoseconds
|
|
mixed clock test
|
|
Add 5 milliseconds to a high_resolution_clock::time_point
|
|
Subtracting system_clock::time_point from monotonic_clock::time_point doesn't compile
|
|
subtract high_resolution_clock::time_point from monotonic_clock::time_point and add that to a system_clock::time_point
|
|
subtract two system_clock::time_point's and output that in microseconds:
|
|
5000 microseconds
|
|
timeval_demo system clock test
|
|
sizeof xtime_clock::time_point = 8
|
|
sizeof xtime_clock::duration = 8
|
|
sizeof xtime_clock::rep = 8
|
|
paused 5001000 nanoseconds
|
|
runtime_resolution test
|
|
paused 5000205 nanoseconds
|
|
C map test
|
|
It is now 10:47:13 2008-4-22
|
|
Round-tripping through the C interface truncated the precision by 255445 microseconds
|
|
2160000
|
|
0
|
|
3600000
|
|
0
|
|
2999998997 * 1/1000000000 seconds
|
|
0 * 1/1000000000 seconds
|
|
15778476000000000 microseconds
|
|
paused 5001000 nanoseconds
|
|
********* milliseconds(3) * 2.5 *********
|
|
The period of milliseconds(3) * 2.5 is 0.001 seconds.
|
|
The frequency of milliseconds(3) * 2.5 is 1000 Hz.
|
|
The representation is floating point
|
|
The precision is the most significant 15 decimal digits.
|
|
The range is +/- 5.69666e+297 years.
|
|
sizeof(milliseconds(3) * 2.5) = 8
|
|
7.5
|
|
milliseconds ms(3.5) doesn't compile
|
|
|
|
Simulated 400MHz clock which has a tick period of 2.5 nanoseconds
|
|
delay = 500 nanoseconds which is 200 cycles
|
|
paused 201 cycles which is 502 nanoseconds
|
|
|
|
Simulated 400MHz clock modeled with nanoseconds
|
|
delay = 500 nanoseconds
|
|
paused 503 nanoseconds
|
|
|
|
Simulated 1500MHz clock which has a tick period of 0.666667 nanoseconds
|
|
delay = 500 nanoseconds which is 750 cycles
|
|
paused 751 cycles which is 500 nanoseconds
|
|
|
|
Simulated 1500MHz clock modeled with nanoseconds
|
|
delay = 500 nanoseconds
|
|
paused 500 nanoseconds
|
|
duration<unsigned>::min().count() = 0
|
|
duration<unsigned>::zero().count() = 0
|
|
duration<unsigned>::max().count() = 4294967295
|
|
duration<int>::min().count() = -2147483647
|
|
duration<int>::zero().count() = 0
|
|
duration<int>::max().count() = 2147483647
|
|
*/</font>
|
|
|
|
<font color="#c80000">/*
|
|
Example disassemblies (to show efficiency).
|
|
Disclaimer: I don't pretend to understand the optimizations made.
|
|
|
|
Compiled with
|
|
g++ -O3 -arch x86_64 -S test2.cpp
|
|
|
|
x86 64-bit architecture
|
|
|
|
********************
|
|
|
|
system_clock::duration
|
|
time_subtraction(system_clock::time_point x, system_clock::time_point y)
|
|
{
|
|
return x - y;
|
|
}
|
|
|
|
pushq %rbp
|
|
LCFI25:
|
|
subq %rsi, %rdi
|
|
movq %rdi, %rax
|
|
movq %rsp, %rbp
|
|
LCFI26:
|
|
leave
|
|
ret
|
|
|
|
********************
|
|
|
|
seconds
|
|
time_subtract_to_seconds(system_clock::time_point x, system_clock::time_point y)
|
|
{
|
|
return duration_cast<seconds>(x - y);
|
|
}
|
|
|
|
subq %rsi, %rdi
|
|
movabsq $4835703278458516699, %rdx
|
|
pushq %rbp
|
|
LCFI25:
|
|
movq %rdi, %rax
|
|
sarq $63, %rdi
|
|
imulq %rdx
|
|
movq %rsp, %rbp
|
|
LCFI26:
|
|
leave
|
|
sarq $18, %rdx
|
|
subq %rdi, %rdx
|
|
movq %rdx, %rax
|
|
ret
|
|
|
|
********************
|
|
|
|
nanoseconds
|
|
time_subtract_to_nanoseconds(system_clock::time_point x, system_clock::time_point y)
|
|
{
|
|
return x - y;
|
|
}
|
|
|
|
pushq %rbp
|
|
LCFI25:
|
|
subq %rsi, %rdi
|
|
imulq $1000, %rdi, %rax
|
|
movq %rsp, %rbp
|
|
LCFI26:
|
|
leave
|
|
ret
|
|
|
|
********************
|
|
|
|
system_clock::time_point
|
|
time_plus_duration(system_clock::time_point x, system_clock::duration y)
|
|
{
|
|
return x + y;
|
|
}
|
|
|
|
pushq %rbp
|
|
LCFI37:
|
|
movq %rsp, %rbp
|
|
LCFI38:
|
|
leaq (%rsi,%rdi), %rax
|
|
leave
|
|
ret
|
|
|
|
********************
|
|
|
|
milliseconds
|
|
duration_plus_duration(milliseconds x, milliseconds y)
|
|
{
|
|
return x + y;
|
|
}
|
|
|
|
pushq %rbp
|
|
LCFI11:
|
|
leaq (%rdi,%rsi), %rax
|
|
movq %rsp, %rbp
|
|
LCFI12:
|
|
leave
|
|
ret
|
|
|
|
********************
|
|
|
|
nanoseconds
|
|
milliseconds_plus_nanoseconds(milliseconds x, nanoseconds y)
|
|
{
|
|
return x + y;
|
|
}
|
|
|
|
imulq $1000000, %rdi, %rdi
|
|
pushq %rbp
|
|
LCFI20:
|
|
movq %rsp, %rbp
|
|
LCFI21:
|
|
leave
|
|
leaq (%rdi,%rsi), %rax
|
|
ret
|
|
|
|
********************
|
|
|
|
milliseconds
|
|
nanoseconds_to_milliseconds(nanoseconds x)
|
|
{
|
|
return duration_cast<milliseconds>(x);
|
|
}
|
|
|
|
movq %rdi, %rax
|
|
movabsq $4835703278458516699, %rdx
|
|
pushq %rbp
|
|
LCFI13:
|
|
imulq %rdx
|
|
sarq $63, %rdi
|
|
movq %rsp, %rbp
|
|
LCFI14:
|
|
leave
|
|
sarq $18, %rdx
|
|
subq %rdi, %rdx
|
|
movq %rdx, %rax
|
|
ret
|
|
|
|
********************
|
|
|
|
nanoseconds
|
|
milliseconds_to_nanoseconds(milliseconds x)
|
|
{
|
|
return x;
|
|
}
|
|
|
|
pushq %rbp
|
|
LCFI13:
|
|
imulq $1000000, %rdi, %rax
|
|
movq %rsp, %rbp
|
|
LCFI14:
|
|
leave
|
|
ret
|
|
|
|
********************
|
|
|
|
hours
|
|
increment_hours(hours x)
|
|
{
|
|
return ++x;
|
|
}
|
|
|
|
pushq %rbp
|
|
LCFI11:
|
|
leaq 1(%rdi), %rax
|
|
movq %rsp, %rbp
|
|
LCFI12:
|
|
leave
|
|
ret
|
|
|
|
*/</font>
|
|
</pre>
|
|
|
|
</body></html> |