unsigned int CalculateNextWorkRequired(arith_uint256 bnAvg,
int64_t nLastBlockTime, int64_t nFirstBlockTime,
const Consensus::Params& params)
{
// Limit adjustment step
// Use medians to prevent time-warp attacks
int64_t nActualTimespan = nLastBlockTime - nFirstBlockTime;
LogPrint("pow", " nActualTimespan = %d before dampening\n", nActualTimespan);
nActualTimespan = params.AveragingWindowTimespan() + (nActualTimespan - params.AveragingWindowTimespan())/4;
LogPrint("pow", " nActualTimespan = %d before bounds\n", nActualTimespan);
if (nActualTimespan < params.MinActualTimespan())
nActualTimespan = params.MinActualTimespan();
if (nActualTimespan > params.MaxActualTimespan())
nActualTimespan = params.MaxActualTimespan();
// Retarget
const arith_uint256 bnPowLimit = UintToArith256(params.powLimit);
arith_uint256 bnNew {bnAvg};
bnNew /= params.AveragingWindowTimespan();
bnNew *= nActualTimespan;
if (bnNew > bnPowLimit)
bnNew = bnPowLimit;
/// debug print
LogPrint("pow", "GetNextWorkRequired RETARGET\n");
LogPrint("pow", "params.AveragingWindowTimespan() = %d nActualTimespan = %d\n", params.AveragingWindowTimespan(), nActualTimespan);
LogPrint("pow", "Current average: %08x %s\n", bnAvg.GetCompact(), bnAvg.ToString());
LogPrint("pow", "After: %08x %s\n", bnNew.GetCompact(), bnNew.ToString());
return bnNew.GetCompact();
}
unsigned int CalculateNextWorkRequired(arith_uint256 bnAvg, int64_t nLastBlockTime, int64_t nFirstBlockTime, const Consensus::Params& params)
{
// Limit adjustment
int64_t nActualTimespan = nLastBlockTime - nFirstBlockTime;
if (nActualTimespan < params.MinActualTimespan())
nActualTimespan = params.MinActualTimespan();
if (nActualTimespan > params.MaxActualTimespan())
nActualTimespan = params.MaxActualTimespan();
// Retarget
const arith_uint256 bnPowLimit = UintToArith256(params.PowLimit(true));
arith_uint256 bnNew {bnAvg};
bnNew /= params.AveragingWindowTimespan();
bnNew *= nActualTimespan;
if (bnNew > bnPowLimit)
bnNew = bnPowLimit;
return bnNew.GetCompact();
}