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/*
* Copyright (C) 2003-2015 The Music Player Daemon Project
* http://www.musicpd.org
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#ifndef MPD_CHRONO_HXX
#define MPD_CHRONO_HXX
#include "Compiler.h"
#include <chrono>
#include <utility>
#include <cstdint>
#if GCC_OLDER_THAN(4,7)
/* std::chrono::duration operators are "constexpr" since gcc 4.7 */
#define chrono_constexpr gcc_pure
#else
#define chrono_constexpr constexpr
#endif
/**
* A time stamp within a song. Granularity is 1 millisecond and the
* maximum value is about 49 days.
*/
class SongTime : public std::chrono::duration<std::uint32_t, std::milli> {
typedef std::chrono::duration<std::uint32_t, std::milli> Base;
typedef Base::rep rep;
public:
SongTime() = default;
template<typename T>
explicit constexpr SongTime(T t):Base(t) {}
static constexpr SongTime zero() {
return SongTime(Base::zero());
}
static constexpr SongTime FromS(unsigned s) {
return SongTime(rep(s) * 1000);
}
static constexpr SongTime FromS(float s) {
return SongTime(rep(s * 1000));
}
static constexpr SongTime FromS(double s) {
return SongTime(rep(s * 1000));
}
static constexpr SongTime FromMS(rep ms) {
return SongTime(ms);
}
constexpr rep ToS() const {
return count() / rep(1000);
}
constexpr rep RoundS() const {
return (count() + 500) / rep(1000);
}
constexpr rep ToMS() const {
return count();
}
template<typename T=rep>
constexpr T ToScale(unsigned scale) const {
return count() * T(scale) / 1000;
}
/**
* Convert a scalar value with the given scale to a #SongTime
* instance.
*
* @param value the input value
* @param scale the value's scale in Hz
*/
template<typename T=rep>
static constexpr SongTime FromScale(T value, unsigned scale) {
return SongTime(value * T(1000) / T(scale));
}
constexpr double ToDoubleS() const {
return double(count()) / 1000.;
};
constexpr bool IsZero() const {
return count() == 0;
}
constexpr bool IsPositive() const {
return count() > 0;
}
chrono_constexpr SongTime operator+(const SongTime &other) const {
return SongTime(*(const Base *)this + (const Base &)other);
}
chrono_constexpr SongTime operator-(const SongTime &other) const {
return SongTime(*(const Base *)this - (const Base &)other);
}
};
/**
* A variant of #SongTime that is based on a signed integer. It can
* be used for relative values.
*/
class SignedSongTime : public std::chrono::duration<std::int32_t, std::milli> {
typedef std::chrono::duration<std::int32_t, std::milli> Base;
typedef Base::rep rep;
public:
SignedSongTime() = default;
template<typename T>
explicit constexpr SignedSongTime(T t):Base(t) {}
/**
* Allow implicit conversion from SongTime to SignedSongTime.
*/
constexpr SignedSongTime(SongTime t):Base(t) {}
static constexpr SignedSongTime zero() {
return SignedSongTime(Base::zero());
}
/**
* Generate a negative value.
*/
static constexpr SignedSongTime Negative() {
return SignedSongTime(-1);
}
static constexpr SignedSongTime FromS(int s) {
return SignedSongTime(rep(s) * 1000);
}
static constexpr SignedSongTime FromS(unsigned s) {
return SignedSongTime(rep(s) * 1000);
}
static constexpr SignedSongTime FromS(float s) {
return SignedSongTime(rep(s * 1000));
}
static constexpr SignedSongTime FromS(double s) {
return SignedSongTime(rep(s * 1000));
}
static constexpr SignedSongTime FromMS(rep ms) {
return SignedSongTime(ms);
}
constexpr rep ToS() const {
return count() / rep(1000);
}
constexpr rep RoundS() const {
return (count() + 500) / rep(1000);
}
constexpr rep ToMS() const {
return count();
}
template<typename T=rep>
constexpr T ToScale(unsigned scale) const {
return count() * T(scale) / 1000;
}
/**
* Convert a scalar value with the given scale to a
* #SignedSongTime instance.
*
* @param value the input value
* @param scale the value's scale in Hz
*/
template<typename T=rep>
static constexpr SignedSongTime FromScale(T value, unsigned scale) {
return SignedSongTime(value * T(1000) / T(scale));
}
constexpr double ToDoubleS() const {
return double(count()) / 1000.;
};
constexpr bool IsZero() const {
return count() == 0;
}
constexpr bool IsPositive() const {
return count() > 0;
}
constexpr bool IsNegative() const {
return count() < 0;
}
chrono_constexpr SignedSongTime operator+(const SignedSongTime &other) const {
return SignedSongTime(*(const Base *)this + (const Base &)other);
}
chrono_constexpr SignedSongTime operator-(const SignedSongTime &other) const {
return SignedSongTime(*(const Base *)this - (const Base &)other);
}
};
#undef chrono_constexpr
#endif
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