library/cpp/actors/core/monotonic.cpp


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#include "monotonic.h" 
 
#include <chrono> 
 
namespace NActors { 
 
    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 NActors