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/*
* Copyright 2022 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#pragma once
#include <chrono>
#include <string>
#include <android-base/stringprintf.h>
#include <utils/Timers.h>
namespace android {
namespace scheduler {
// TODO(b/185535769): Pull Clock.h to libscheduler to reuse this.
using SchedulerClock = std::chrono::steady_clock;
static_assert(SchedulerClock::is_steady);
} // namespace scheduler
struct Duration;
struct TimePoint : scheduler::SchedulerClock::time_point {
constexpr TimePoint() = default;
explicit constexpr TimePoint(const Duration&);
// Implicit conversion from std::chrono counterpart.
constexpr TimePoint(scheduler::SchedulerClock::time_point p)
: scheduler::SchedulerClock::time_point(p) {}
static constexpr TimePoint fromNs(nsecs_t);
static TimePoint now() { return scheduler::SchedulerClock::now(); };
nsecs_t ns() const;
};
struct Duration : TimePoint::duration {
// Implicit conversion from std::chrono counterpart.
template <typename R, typename P>
constexpr Duration(std::chrono::duration<R, P> d) : TimePoint::duration(d) {}
static constexpr Duration fromNs(nsecs_t ns) { return {std::chrono::nanoseconds(ns)}; }
nsecs_t ns() const { return std::chrono::nanoseconds(*this).count(); }
};
using Period = Duration;
constexpr TimePoint::TimePoint(const Duration& d) : scheduler::SchedulerClock::time_point(d) {}
constexpr TimePoint TimePoint::fromNs(nsecs_t ns) {
return TimePoint(Duration::fromNs(ns));
}
inline nsecs_t TimePoint::ns() const {
return Duration(time_since_epoch()).ns();
}
// Shorthand to convert the tick count of a Duration to Period and Rep. For example:
//
// const auto i = ticks<std::ratio<1>>(d); // Integer seconds.
// const auto f = ticks<std::milli, float>(d); // Floating-point milliseconds.
//
template <typename Period, typename Rep = Duration::rep>
constexpr Rep ticks(Duration d) {
using D = std::chrono::duration<Rep, Period>;
return std::chrono::duration_cast<D>(d).count();
}
inline std::string to_string(Duration d) {
return base::StringPrintf("%.3f ms", ticks<std::milli, float>(d));
}
} // namespace android
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