library/cpp/time_provider/monotonic.cpp


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#include "monotonic.h"

#include <chrono>

namespace NMonotonic {

namespace {
// Unfortunately time_since_epoch() is sometimes negative on wine
// Remember initial time point at program start and use offsets from that
std::chrono::steady_clock::time_point MonotonicOffset = std::chrono::steady_clock::now();
}

ui64 GetMonotonicMicroSeconds() {
    auto microseconds = std::chrono::duration_cast<std::chrono::microseconds>(std::chrono::steady_clock::now() - MonotonicOffset).count();
    // Steady clock is supposed to never jump backwards, but it's better to be safe in case of buggy implementations
    if (Y_UNLIKELY(microseconds < 0)) {
        microseconds = 0;
    }
    // Add one so we never return zero
    return microseconds + 1;
}

} // namespace TMonotonic

template<>
void Out<NMonotonic::TMonotonic>(
    IOutputStream& o,
    NMonotonic::TMonotonic t)
{
    o << t - NMonotonic::TMonotonic::Zero();
}