diff options
Diffstat (limited to 'src/main.cpp')
-rw-r--r-- | src/main.cpp | 113 |
1 files changed, 1 insertions, 112 deletions
diff --git a/src/main.cpp b/src/main.cpp index d3f04b95fa..ea47601081 100644 --- a/src/main.cpp +++ b/src/main.cpp @@ -12,6 +12,7 @@ #include "checkqueue.h" #include "init.h" #include "net.h" +#include "pow.h" #include "txdb.h" #include "txmempool.h" #include "ui_interface.h" @@ -1194,118 +1195,6 @@ int64_t GetBlockValue(int nHeight, int64_t nFees) return nSubsidy + nFees; } -static const int64_t nTargetTimespan = 14 * 24 * 60 * 60; // two weeks -static const int64_t nTargetSpacing = 10 * 60; -static const int64_t nInterval = nTargetTimespan / nTargetSpacing; - -// -// minimum amount of work that could possibly be required nTime after -// minimum work required was nBase -// -unsigned int ComputeMinWork(unsigned int nBase, int64_t nTime) -{ - const uint256 &bnLimit = Params().ProofOfWorkLimit(); - // Testnet has min-difficulty blocks - // after nTargetSpacing*2 time between blocks: - if (Params().AllowMinDifficultyBlocks() && nTime > nTargetSpacing*2) - return bnLimit.GetCompact(); - - uint256 bnResult; - bnResult.SetCompact(nBase); - while (nTime > 0 && bnResult < bnLimit) - { - // Maximum 400% adjustment... - bnResult *= 4; - // ... in best-case exactly 4-times-normal target time - nTime -= nTargetTimespan*4; - } - if (bnResult > bnLimit) - bnResult = bnLimit; - return bnResult.GetCompact(); -} - -unsigned int GetNextWorkRequired(const CBlockIndex* pindexLast, const CBlockHeader *pblock) -{ - unsigned int nProofOfWorkLimit = Params().ProofOfWorkLimit().GetCompact(); - - // Genesis block - if (pindexLast == NULL) - return nProofOfWorkLimit; - - // Only change once per interval - if ((pindexLast->nHeight+1) % nInterval != 0) - { - if (Params().AllowMinDifficultyBlocks()) - { - // Special difficulty rule for testnet: - // If the new block's timestamp is more than 2* 10 minutes - // then allow mining of a min-difficulty block. - if (pblock->nTime > pindexLast->nTime + nTargetSpacing*2) - return nProofOfWorkLimit; - else - { - // Return the last non-special-min-difficulty-rules-block - const CBlockIndex* pindex = pindexLast; - while (pindex->pprev && pindex->nHeight % nInterval != 0 && pindex->nBits == nProofOfWorkLimit) - pindex = pindex->pprev; - return pindex->nBits; - } - } - return pindexLast->nBits; - } - - // Go back by what we want to be 14 days worth of blocks - const CBlockIndex* pindexFirst = pindexLast; - for (int i = 0; pindexFirst && i < nInterval-1; i++) - pindexFirst = pindexFirst->pprev; - assert(pindexFirst); - - // Limit adjustment step - int64_t nActualTimespan = pindexLast->GetBlockTime() - pindexFirst->GetBlockTime(); - LogPrintf(" nActualTimespan = %d before bounds\n", nActualTimespan); - if (nActualTimespan < nTargetTimespan/4) - nActualTimespan = nTargetTimespan/4; - if (nActualTimespan > nTargetTimespan*4) - nActualTimespan = nTargetTimespan*4; - - // Retarget - uint256 bnNew; - uint256 bnOld; - bnNew.SetCompact(pindexLast->nBits); - bnOld = bnNew; - bnNew *= nActualTimespan; - bnNew /= nTargetTimespan; - - if (bnNew > Params().ProofOfWorkLimit()) - bnNew = Params().ProofOfWorkLimit(); - - /// debug print - LogPrintf("GetNextWorkRequired RETARGET\n"); - LogPrintf("nTargetTimespan = %d nActualTimespan = %d\n", nTargetTimespan, nActualTimespan); - LogPrintf("Before: %08x %s\n", pindexLast->nBits, bnOld.ToString()); - LogPrintf("After: %08x %s\n", bnNew.GetCompact(), bnNew.ToString()); - - return bnNew.GetCompact(); -} - -bool CheckProofOfWork(uint256 hash, unsigned int nBits) -{ - bool fNegative; - bool fOverflow; - uint256 bnTarget; - bnTarget.SetCompact(nBits, &fNegative, &fOverflow); - - // Check range - if (fNegative || bnTarget == 0 || fOverflow || bnTarget > Params().ProofOfWorkLimit()) - return error("CheckProofOfWork() : nBits below minimum work"); - - // Check proof of work matches claimed amount - if (hash > bnTarget) - return error("CheckProofOfWork() : hash doesn't match nBits"); - - return true; -} - bool IsInitialBlockDownload() { LOCK(cs_main); |