41 lines
806 B
C
41 lines
806 B
C
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#pragma once
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#include <algorithm>
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#include <random>
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#include <stdint.h>
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#include <time.h>
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struct Backoff {
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int64_t minAmount;
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int64_t maxAmount;
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int64_t current;
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int fails;
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std::mt19937_64 randGenerator;
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std::uniform_real_distribution<> randDistribution;
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double rand01() { return randDistribution(randGenerator); }
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Backoff(int64_t min, int64_t max)
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: minAmount(min)
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, maxAmount(max)
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, current(min)
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, fails(0)
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, randGenerator((uint64_t)time(0))
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{
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}
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void reset()
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{
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fails = 0;
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current = minAmount;
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}
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int64_t nextDelay()
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{
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++fails;
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int64_t delay = (int64_t)((double)current * 2.0 * rand01());
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current = std::min(current + delay, maxAmount);
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return current;
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}
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};
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