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/*
* Copyright (C) 2003-2014 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 <chrono>
#include <cstdint>
/**
* 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) {}
/**
* This constructor allows implicit conversion from the base
* class to this class. It is necessary because all of
* std::chrono::duration's operators return another
* std::chrono::duration and not an instance of this class.
*/
constexpr SongTime(Base b):Base(b) {}
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 ToMS() const {
return count();
}
template<typename T=rep>
constexpr T ToScale(unsigned base) const {
return count() * T(base) / 1000;
}
constexpr double ToDoubleS() const {
return double(count()) / 1000.;
};
constexpr bool IsZero() const {
return count() == 0;
}
constexpr bool IsPositive() const {
return count() > 0;
}
};
/**
* 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) {}
/**
* This constructor allows implicit conversion from the base
* class to this class. It is necessary because all of
* std::chrono::duration's operators return another
* std::chrono::duration and not an instance of this class.
*/
constexpr SignedSongTime(Base b):Base(b) {}
static constexpr SignedSongTime FromS(int 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 ToMS() const {
return count();
}
template<typename T=rep>
constexpr T ToScale(unsigned base) const {
return count() * T(base) / 1000;
}
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;
}
};
#endif
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