tdlight/tdutils/td/utils/Time.cpp
2021-01-01 15:57:46 +03:00

48 lines
1.1 KiB
C++

//
// Copyright Aliaksei Levin (levlam@telegram.org), Arseny Smirnov (arseny30@gmail.com) 2014-2021
//
// Distributed under the Boost Software License, Version 1.0. (See accompanying
// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
//
#include "td/utils/Time.h"
#include <atomic>
#include <cmath>
namespace td {
bool operator==(Timestamp a, Timestamp b) {
return std::abs(a.at() - b.at()) < 1e-6;
}
static std::atomic<double> time_diff;
double Time::now() {
auto result = now_unadjusted() + time_diff.load(std::memory_order_relaxed);
while (result < 0) {
auto old_time_diff = time_diff.load();
time_diff.compare_exchange_strong(old_time_diff, old_time_diff - result);
result = now_unadjusted() + time_diff.load(std::memory_order_relaxed);
}
return result;
}
double Time::now_unadjusted() {
return Clocks::monotonic();
}
void Time::jump_in_future(double at) {
while (true) {
auto old_time_diff = time_diff.load();
auto diff = at - now();
if (diff < 0) {
return;
}
if (time_diff.compare_exchange_strong(old_time_diff, old_time_diff + diff)) {
return;
}
}
}
} // namespace td