SpartaExpBackoff.hpp

// <SpartaExpBackoff> -*- C++ -*-
 
#pragma once
 
#include <cstdint>
 
namespace sparta {
 
    namespace exp_backoff {
 
typedef uint32_t counter_t;
 
#define SPARTA_EXPBO_CONCAT_ARG2(x,y,z) x##_##y##_##z
 
#define SPARTA_EXPBO_CONCAT_ARG(x,y,z) SPARTA_EXPBO_CONCAT_ARG2(x,y,z)
 
#define SPARTA_EXPONENTIAL_BACKOFF(mult, action)                                            \
    static sparta::exp_backoff::counter_t SPARTA_EXPBO_CONCAT_ARG(_count,__LINE__,mult) = 0;  \
    static sparta::exp_backoff::counter_t SPARTA_EXPBO_CONCAT_ARG(_next,__LINE__,mult) = 1;   \
    SPARTA_EXPBO_CONCAT_ARG(_count,__LINE__,mult) ++;                                       \
    if(SPARTA_EXPBO_CONCAT_ARG(_count,__LINE__,mult) >= SPARTA_EXPBO_CONCAT_ARG(_next,__LINE__,mult)){ \
        const sparta::exp_backoff::counter_t& SPARTA_EXPONENTIAL_BACKOFF_COUNT = SPARTA_EXPBO_CONCAT_ARG(_count,__LINE__,mult); \
        (void) SPARTA_EXPONENTIAL_BACKOFF_COUNT;                                            \
        action;                                                                           \
        SPARTA_EXPBO_CONCAT_ARG(_next,__LINE__,mult) *= mult;                               \
    }
 
    } // namespace exp_backoff
} // namespace sparta