diff options
| -rw-r--r-- | src/chain.cpp | 32 | ||||
| -rw-r--r-- | src/chain.h | 4 | ||||
| -rw-r--r-- | src/pow.cpp | 32 | ||||
| -rw-r--r-- | src/pow.h | 5 |
4 files changed, 36 insertions, 37 deletions
diff --git a/src/chain.cpp b/src/chain.cpp index 3450ed6c3f..32f6480f84 100644 --- a/src/chain.cpp +++ b/src/chain.cpp @@ -110,3 +110,35 @@ void CBlockIndex::BuildSkip() if (pprev) pskip = pprev->GetAncestor(GetSkipHeight(nHeight)); } + +arith_uint256 GetBlockProof(const CBlockIndex& block) +{ + arith_uint256 bnTarget; + bool fNegative; + bool fOverflow; + bnTarget.SetCompact(block.nBits, &fNegative, &fOverflow); + if (fNegative || fOverflow || bnTarget == 0) + return 0; + // We need to compute 2**256 / (bnTarget+1), but we can't represent 2**256 + // as it's too large for a arith_uint256. However, as 2**256 is at least as large + // as bnTarget+1, it is equal to ((2**256 - bnTarget - 1) / (bnTarget+1)) + 1, + // or ~bnTarget / (nTarget+1) + 1. + return (~bnTarget / (bnTarget + 1)) + 1; +} + +int64_t GetBlockProofEquivalentTime(const CBlockIndex& to, const CBlockIndex& from, const CBlockIndex& tip, const Consensus::Params& params) +{ + arith_uint256 r; + int sign = 1; + if (to.nChainWork > from.nChainWork) { + r = to.nChainWork - from.nChainWork; + } else { + r = from.nChainWork - to.nChainWork; + sign = -1; + } + r = r * arith_uint256(params.nPowTargetSpacing) / GetBlockProof(tip); + if (r.bits() > 63) { + return sign * std::numeric_limits<int64_t>::max(); + } + return sign * r.GetLow64(); +} diff --git a/src/chain.h b/src/chain.h index b9b1b9306f..9199983565 100644 --- a/src/chain.h +++ b/src/chain.h @@ -282,6 +282,10 @@ public: const CBlockIndex* GetAncestor(int height) const; }; +arith_uint256 GetBlockProof(const CBlockIndex& block); +/** Return the time it would take to redo the work difference between from and to, assuming the current hashrate corresponds to the difficulty at tip, in seconds. */ +int64_t GetBlockProofEquivalentTime(const CBlockIndex& to, const CBlockIndex& from, const CBlockIndex& tip, const Consensus::Params&); + /** Used to marshal pointers into hashes for db storage. */ class CDiskBlockIndex : public CBlockIndex { diff --git a/src/pow.cpp b/src/pow.cpp index 7392defe64..40c72f9d79 100644 --- a/src/pow.cpp +++ b/src/pow.cpp @@ -102,35 +102,3 @@ bool CheckProofOfWork(uint256 hash, unsigned int nBits, const Consensus::Params& return true; } - -arith_uint256 GetBlockProof(const CBlockIndex& block) -{ - arith_uint256 bnTarget; - bool fNegative; - bool fOverflow; - bnTarget.SetCompact(block.nBits, &fNegative, &fOverflow); - if (fNegative || fOverflow || bnTarget == 0) - return 0; - // We need to compute 2**256 / (bnTarget+1), but we can't represent 2**256 - // as it's too large for a arith_uint256. However, as 2**256 is at least as large - // as bnTarget+1, it is equal to ((2**256 - bnTarget - 1) / (bnTarget+1)) + 1, - // or ~bnTarget / (nTarget+1) + 1. - return (~bnTarget / (bnTarget + 1)) + 1; -} - -int64_t GetBlockProofEquivalentTime(const CBlockIndex& to, const CBlockIndex& from, const CBlockIndex& tip, const Consensus::Params& params) -{ - arith_uint256 r; - int sign = 1; - if (to.nChainWork > from.nChainWork) { - r = to.nChainWork - from.nChainWork; - } else { - r = from.nChainWork - to.nChainWork; - sign = -1; - } - r = r * arith_uint256(params.nPowTargetSpacing) / GetBlockProof(tip); - if (r.bits() > 63) { - return sign * std::numeric_limits<int64_t>::max(); - } - return sign * r.GetLow64(); -} @@ -13,16 +13,11 @@ class CBlockHeader; class CBlockIndex; class uint256; -class arith_uint256; unsigned int GetNextWorkRequired(const CBlockIndex* pindexLast, const CBlockHeader *pblock, const Consensus::Params&); unsigned int CalculateNextWorkRequired(const CBlockIndex* pindexLast, int64_t nFirstBlockTime, const Consensus::Params&); /** Check whether a block hash satisfies the proof-of-work requirement specified by nBits */ bool CheckProofOfWork(uint256 hash, unsigned int nBits, const Consensus::Params&); -arith_uint256 GetBlockProof(const CBlockIndex& block); - -/** Return the time it would take to redo the work difference between from and to, assuming the current hashrate corresponds to the difficulty at tip, in seconds. */ -int64_t GetBlockProofEquivalentTime(const CBlockIndex& to, const CBlockIndex& from, const CBlockIndex& tip, const Consensus::Params&); #endif // BITCOIN_POW_H |