Hold cs_main while calling UpdatedBlockTip() and ui.NotifyBlockTip

Ensures that callbacks are invoked in the order in which the chain is updated
Resolves #12978
This commit is contained in:
Jesse Cohen 2018-04-15 11:22:28 -04:00
parent 5f2a39946f
commit d86edd3d30
2 changed files with 14 additions and 11 deletions

View file

@ -353,7 +353,7 @@ bool CheckSequenceLocks(const CTransaction &tx, int flags, LockPoints* lp, bool
CBlockIndex* tip = chainActive.Tip();
assert(tip != nullptr);
CBlockIndex index;
index.pprev = tip;
// CheckSequenceLocks() uses chainActive.Height()+1 to evaluate
@ -2677,19 +2677,18 @@ bool CChainState::ActivateBestChain(CValidationState &state, const CChainParams&
assert(trace.pblock && trace.pindex);
GetMainSignals().BlockConnected(trace.pblock, trace.pindex, trace.conflictedTxs);
}
// Notify external listeners about the new tip.
// Enqueue while holding cs_main to ensure that UpdatedBlockTip is called in the order in which blocks are connected
GetMainSignals().UpdatedBlockTip(pindexNewTip, pindexFork, fInitialDownload);
// Always notify the UI if a new block tip was connected
if (pindexFork != pindexNewTip) {
uiInterface.NotifyBlockTip(fInitialDownload, pindexNewTip);
}
}
// When we reach this point, we switched to a new tip (stored in pindexNewTip).
// Notifications/callbacks that can run without cs_main
// Notify external listeners about the new tip.
GetMainSignals().UpdatedBlockTip(pindexNewTip, pindexFork, fInitialDownload);
// Always notify the UI if a new block tip was connected
if (pindexFork != pindexNewTip) {
uiInterface.NotifyBlockTip(fInitialDownload, pindexNewTip);
}
if (nStopAtHeight && pindexNewTip && pindexNewTip->nHeight >= nStopAtHeight) StartShutdown();
// We check shutdown only after giving ActivateBestChainStep a chance to run once so that we

View file

@ -139,6 +139,10 @@ void CMainSignals::MempoolEntryRemoved(CTransactionRef ptx, MemPoolRemovalReason
}
void CMainSignals::UpdatedBlockTip(const CBlockIndex *pindexNew, const CBlockIndex *pindexFork, bool fInitialDownload) {
// Dependencies exist that require UpdatedBlockTip events to be delivered in the order in which
// the chain actually updates. One way to ensure this is for the caller to invoke this signal
// in the same critical section where the chain is updated
m_internals->m_schedulerClient.AddToProcessQueue([pindexNew, pindexFork, fInitialDownload, this] {
m_internals->UpdatedBlockTip(pindexNew, pindexFork, fInitialDownload);
});