dogecoin/src/dogecoin.cpp
2018-09-19 19:21:49 +01:00

101 lines
3.7 KiB
C++

// Copyright (c) 2015 The Dogecoin Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
#include <boost/random/uniform_int.hpp>
#include <boost/random/mersenne_twister.hpp>
#include "arith_uint256.h"
#include "dogecoin.h"
#include "util.h"
int static generateMTRandom(unsigned int s, int range)
{
boost::mt19937 gen(s);
boost::uniform_int<> dist(1, range);
return dist(gen);
}
unsigned int CalculateDogecoinNextWorkRequired(const CBlockIndex* pindexLast, int64_t nFirstBlockTime, const Consensus::Params& params)
{
int nHeight = pindexLast->nHeight + 1;
bool fNewDifficultyProtocol = (nHeight >= 145000);
// bool fNewDifficultyProtocol = (nHeight >= params.GetDigiShieldForkBlock());
const int64_t retargetTimespan = fNewDifficultyProtocol
? 60 // params.DigiShieldTargetTimespan()
: params.nPowTargetTimespan;
const int64_t nActualTimespan = pindexLast->GetBlockTime() - nFirstBlockTime;
int64_t nModulatedTimespan = nActualTimespan;
int64_t nMaxTimespan;
int64_t nMinTimespan;
if (fNewDifficultyProtocol) //DigiShield implementation - thanks to RealSolid & WDC for this code
{
// amplitude filter - thanks to daft27 for this code
nModulatedTimespan = retargetTimespan + (nModulatedTimespan - retargetTimespan) / 8;
nMinTimespan = retargetTimespan - (retargetTimespan / 4);
nMaxTimespan = retargetTimespan + (retargetTimespan / 2);
} else if (nHeight > 10000) {
nMinTimespan = retargetTimespan / 4;
nMaxTimespan = retargetTimespan * 4;
} else if (nHeight > 5000) {
nMinTimespan = retargetTimespan / 8;
nMaxTimespan = retargetTimespan * 4;
} else {
nMinTimespan = retargetTimespan / 16;
nMaxTimespan = retargetTimespan * 4;
}
// Limit adjustment step
if (nModulatedTimespan < nMinTimespan)
nModulatedTimespan = nMinTimespan;
else if (nModulatedTimespan > nMaxTimespan)
nModulatedTimespan = nMaxTimespan;
// Retarget
const arith_uint256 bnPowLimit = UintToArith256(params.powLimit);
arith_uint256 bnNew;
arith_uint256 bnOld;
bnNew.SetCompact(pindexLast->nBits);
bnOld = bnNew;
bnNew *= nModulatedTimespan;
bnNew /= retargetTimespan;
if (bnNew > bnPowLimit)
bnNew = bnPowLimit;
/// debug print
LogPrintf("GetNextWorkRequired RETARGET\n");
LogPrintf("params.nPowTargetTimespan = %d nActualTimespan = %d\n", params.nPowTargetTimespan, nActualTimespan);
LogPrintf("Before: %08x %s\n", pindexLast->nBits, bnOld.ToString());
LogPrintf("After: %08x %s\n", bnNew.GetCompact(), bnNew.ToString());
return bnNew.GetCompact();
}
CAmount GetDogecoinBlockSubsidy(int nHeight, const Consensus::Params& consensusParams, uint256 prevHash)
{
int halvings = nHeight / consensusParams.nSubsidyHalvingInterval;
if (nHeight < 145000) // && !consensusParams.SimplifiedRewards())
{
// Old-style rewards derived from the previous block hash
const std::string cseed_str = prevHash.ToString().substr(7, 7);
const char* cseed = cseed_str.c_str();
char* endp = NULL;
long seed = strtol(cseed, &endp, 16);
CAmount maxReward = (1000000 >> halvings) - 1;
int rand = generateMTRandom(seed, maxReward);
return (1 + rand) * COIN;
} else if (nHeight < (6 * consensusParams.nSubsidyHalvingInterval)) {
// New-style constant rewards for each halving interval
return (500000 * COIN) >> halvings;
} else {
// Constant inflation
return 10000 * COIN;
}
}