Introduce NotifyChainLock signal and invoke it when CLSIGs get processed

Author: codablock

src/llmq/quorums_chainlocks.cpp

@@ -149,6 +149,11 @@ void CChainLocksHandler::ProcessNewChainLock(NodeId from, const llmq::CChainLock
 
     LogPrintf("CChainLocksHandler::%s -- processed new CLSIG (%s), peer=%d\n",
               __func__, clsig.ToString(), from);
+
+    if (lastNotifyChainLockBlockIndex != bestChainLockBlockIndex) {
+        lastNotifyChainLockBlockIndex = bestChainLockBlockIndex;
+        GetMainSignals().NotifyChainLock(bestChainLockBlockIndex);
+    }
 }
 
 void CChainLocksHandler::AcceptedBlockHeader(const CBlockIndex* pindexNew)
@@ -204,6 +209,11 @@ void CChainLocksHandler::UpdatedBlockTip(const CBlockIndex* pindexNew, const CBl
         if (bestChainLockBlockIndex == pindexNew) {
             // we first got the CLSIG, then the header, and then the block was connected.
             // In this case there is no need to continue here.
+            // However, NotifyChainLock might not have been called yet, so call it now if needed
+            if (lastNotifyChainLockBlockIndex != bestChainLockBlockIndex) {
+                lastNotifyChainLockBlockIndex = bestChainLockBlockIndex;
+                GetMainSignals().NotifyChainLock(bestChainLockBlockIndex);
+            }
             return;
         }
 

src/llmq/quorums_chainlocks.h

@@ -55,6 +55,7 @@ class CChainLocksHandler : public CRecoveredSigsListener
 
     CChainLockSig bestChainLockWithKnownBlock;
     const CBlockIndex* bestChainLockBlockIndex{nullptr};
+    const CBlockIndex* lastNotifyChainLockBlockIndex{nullptr};
 
     int32_t lastSignedHeight{-1};
     uint256 lastSignedRequestId;

src/validationinterface.cpp

@@ -18,6 +18,7 @@ void RegisterValidationInterface(CValidationInterface* pwalletIn) {
     g_signals.UpdatedBlockTip.connect(boost::bind(&CValidationInterface::UpdatedBlockTip, pwalletIn, _1, _2, _3));
     g_signals.SyncTransaction.connect(boost::bind(&CValidationInterface::SyncTransaction, pwalletIn, _1, _2, _3));
     g_signals.NotifyTransactionLock.connect(boost::bind(&CValidationInterface::NotifyTransactionLock, pwalletIn, _1));
+    g_signals.NotifyChainLock.connect(boost::bind(&CValidationInterface::NotifyChainLock, pwalletIn, _1));
     g_signals.UpdatedTransaction.connect(boost::bind(&CValidationInterface::UpdatedTransaction, pwalletIn, _1));
     g_signals.SetBestChain.connect(boost::bind(&CValidationInterface::SetBestChain, pwalletIn, _1));
     g_signals.Inventory.connect(boost::bind(&CValidationInterface::Inventory, pwalletIn, _1));
@@ -40,6 +41,7 @@ void UnregisterValidationInterface(CValidationInterface* pwalletIn) {
     g_signals.Inventory.disconnect(boost::bind(&CValidationInterface::Inventory, pwalletIn, _1));
     g_signals.SetBestChain.disconnect(boost::bind(&CValidationInterface::SetBestChain, pwalletIn, _1));
     g_signals.UpdatedTransaction.disconnect(boost::bind(&CValidationInterface::UpdatedTransaction, pwalletIn, _1));
+    g_signals.NotifyChainLock.disconnect(boost::bind(&CValidationInterface::NotifyChainLock, pwalletIn, _1));
     g_signals.NotifyTransactionLock.disconnect(boost::bind(&CValidationInterface::NotifyTransactionLock, pwalletIn, _1));
     g_signals.SyncTransaction.disconnect(boost::bind(&CValidationInterface::SyncTransaction, pwalletIn, _1, _2, _3));
     g_signals.UpdatedBlockTip.disconnect(boost::bind(&CValidationInterface::UpdatedBlockTip, pwalletIn, _1, _2, _3));
@@ -61,6 +63,7 @@ void UnregisterAllValidationInterfaces() {
     g_signals.SetBestChain.disconnect_all_slots();
     g_signals.UpdatedTransaction.disconnect_all_slots();
     g_signals.NotifyTransactionLock.disconnect_all_slots();
+    g_signals.NotifyChainLock.disconnect_all_slots();
     g_signals.SyncTransaction.disconnect_all_slots();
     g_signals.UpdatedBlockTip.disconnect_all_slots();
     g_signals.NewPoWValidBlock.disconnect_all_slots();

src/validationinterface.h

@@ -39,6 +39,7 @@ class CValidationInterface {
     virtual void UpdatedBlockTip(const CBlockIndex *pindexNew, const CBlockIndex *pindexFork, bool fInitialDownload) {}
     virtual void SyncTransaction(const CTransaction &tx, const CBlockIndex *pindex, int posInBlock) {}
     virtual void NotifyTransactionLock(const CTransaction &tx) {}
+    virtual void NotifyChainLock(const CBlockIndex* pindex) {}
     virtual void NotifyGovernanceVote(const CGovernanceVote &vote) {}
     virtual void NotifyGovernanceObject(const CGovernanceObject &object) {}
     virtual void NotifyInstantSendDoubleSpendAttempt(const CTransaction &currentTx, const CTransaction &previousTx) {}
@@ -76,6 +77,8 @@ struct CMainSignals {
     boost::signals2::signal<void (const CTransaction &, const CBlockIndex *pindex, int posInBlock)> SyncTransaction;
     /** Notifies listeners of an updated transaction lock without new data. */
     boost::signals2::signal<void (const CTransaction &)> NotifyTransactionLock;
+    /** Notifies listeners of a ChainLock. */
+    boost::signals2::signal<void (const CBlockIndex* pindex)> NotifyChainLock;
     /** Notifies listeners of a new governance vote. */
     boost::signals2::signal<void (const CGovernanceVote &)> NotifyGovernanceVote;
     /** Notifies listeners of a new governance object. */