diff options
Diffstat (limited to 'src/chain.cpp')
-rw-r--r-- | src/chain.cpp | 31 |
1 files changed, 25 insertions, 6 deletions
diff --git a/src/chain.cpp b/src/chain.cpp index 8d4c4e7dea..47acde882e 100644 --- a/src/chain.cpp +++ b/src/chain.cpp @@ -9,7 +9,7 @@ * CChain implementation */ void CChain::SetTip(CBlockIndex *pindex) { - if (pindex == NULL) { + if (pindex == nullptr) { vChain.clear(); return; } @@ -49,8 +49,8 @@ CBlockLocator CChain::GetLocator(const CBlockIndex *pindex) const { } const CBlockIndex *CChain::FindFork(const CBlockIndex *pindex) const { - if (pindex == NULL) { - return NULL; + if (pindex == nullptr) { + return nullptr; } if (pindex->nHeight > Height()) pindex = pindex->GetAncestor(Height()); @@ -63,7 +63,7 @@ CBlockIndex* CChain::FindEarliestAtLeast(int64_t nTime) const { std::vector<CBlockIndex*>::const_iterator lower = std::lower_bound(vChain.begin(), vChain.end(), nTime, [](CBlockIndex* pBlock, const int64_t& time) -> bool { return pBlock->GetBlockTimeMax() < time; }); - return (lower == vChain.end() ? NULL : *lower); + return (lower == vChain.end() ? nullptr : *lower); } /** Turn the lowest '1' bit in the binary representation of a number into a '0'. */ @@ -83,14 +83,14 @@ int static inline GetSkipHeight(int height) { CBlockIndex* CBlockIndex::GetAncestor(int height) { if (height > nHeight || height < 0) - return NULL; + return nullptr; CBlockIndex* pindexWalk = this; int heightWalk = nHeight; while (heightWalk > height) { int heightSkip = GetSkipHeight(heightWalk); int heightSkipPrev = GetSkipHeight(heightWalk - 1); - if (pindexWalk->pskip != NULL && + if (pindexWalk->pskip != nullptr && (heightSkip == height || (heightSkip > height && !(heightSkipPrev < heightSkip - 2 && heightSkipPrev >= height)))) { @@ -148,3 +148,22 @@ int64_t GetBlockProofEquivalentTime(const CBlockIndex& to, const CBlockIndex& fr } return sign * r.GetLow64(); } + +/** Find the last common ancestor two blocks have. + * Both pa and pb must be non-nullptr. */ +const CBlockIndex* LastCommonAncestor(const CBlockIndex* pa, const CBlockIndex* pb) { + if (pa->nHeight > pb->nHeight) { + pa = pa->GetAncestor(pb->nHeight); + } else if (pb->nHeight > pa->nHeight) { + pb = pb->GetAncestor(pa->nHeight); + } + + while (pa != pb && pa && pb) { + pa = pa->pprev; + pb = pb->pprev; + } + + // Eventually all chain branches meet at the genesis block. + assert(pa == pb); + return pa; +} |