removeForReorg calls once-per-disconnect-> once-per-reorg

src/main.cpp

@@ -2419,11 +2419,10 @@ void static UpdateTip(CBlockIndex *pindexNew) {
     }
 }
 
-/** Disconnect chainActive's tip. */
+/** Disconnect chainActive's tip. You probably want to call mempool.removeForReorg after this, with cs_main held. */
 bool static DisconnectTip(CValidationState &state, bool fBare = false) {
     CBlockIndex *pindexDelete = chainActive.Tip();
     assert(pindexDelete);
-    mempool.check(pcoinsTip);
     // Read block from disk.
     CBlock block;
     if (!ReadBlockFromDisk(block, pindexDelete))
@@ -2457,8 +2456,6 @@ bool static DisconnectTip(CValidationState &state, bool fBare = false) {
             // in which case we don't want to evict from the mempool yet!
             mempool.removeWithAnchor(anchorBeforeDisconnect);
         }
-        mempool.removeForReorg(pcoinsTip, pindexDelete->nHeight);
-        mempool.check(pcoinsTip);
     }
 
     // Update chainActive and related variables.
@@ -2488,7 +2485,6 @@ static int64_t nTimePostConnect = 0;
  */
 bool static ConnectTip(CValidationState &state, CBlockIndex *pindexNew, CBlock *pblock) {
     assert(pindexNew->pprev == chainActive.Tip());
-    mempool.check(pcoinsTip);
     // Read block from disk.
     int64_t nTime1 = GetTimeMicros();
     CBlock block;
@@ -2528,7 +2524,6 @@ bool static ConnectTip(CValidationState &state, CBlockIndex *pindexNew, CBlock *
     // Remove conflicting transactions from the mempool.
     list<CTransaction> txConflicted;
     mempool.removeForBlock(pblock->vtx, pindexNew->nHeight, txConflicted, !IsInitialBlockDownload());
-    mempool.check(pcoinsTip);
     // Update chainActive & related variables.
     UpdateTip(pindexNew);
     // Tell wallet about transactions that went from mempool
@@ -2632,9 +2627,14 @@ static bool ActivateBestChainStep(CValidationState &state, CBlockIndex *pindexMo
     const CBlockIndex *pindexFork = chainActive.FindFork(pindexMostWork);
 
     // Disconnect active blocks which are no longer in the best chain.
+    bool fBlocksDisconnected = false;
     while (chainActive.Tip() && chainActive.Tip() != pindexFork) {
-        if (!DisconnectTip(state))
+        if (!DisconnectTip(state)) {
+            // Probably an AbortNode() error, but try to keep mempool consistent anyway
+            mempool.removeForReorg(pcoinsTip, chainActive.Tip()->nHeight + 1);
             return false;
+        }
+        fBlocksDisconnected = true;
     }
 
     // Build list of new blocks to connect.
@@ -2667,6 +2667,9 @@ static bool ActivateBestChainStep(CValidationState &state, CBlockIndex *pindexMo
                     break;
                 } else {
                     // A system error occurred (disk space, database error, ...).
+                    // Probably gonna shut down ASAP, but try to keep mempool consistent anyway
+                    if (fBlocksDisconnected)
+                        mempool.removeForReorg(pcoinsTip, chainActive.Tip()->nHeight + 1);
                     return false;
                 }
             } else {
@@ -2680,6 +2683,11 @@ static bool ActivateBestChainStep(CValidationState &state, CBlockIndex *pindexMo
         }
     }
 
+    if (fBlocksDisconnected) {
+        mempool.removeForReorg(pcoinsTip, chainActive.Tip()->nHeight + 1);
+    }
+    mempool.check(pcoinsTip);
+
     // Callbacks/notifications for a new best chain.
     if (fInvalidFound)
         CheckForkWarningConditionsOnNewFork(vpindexToConnect.back());
@@ -2764,6 +2772,7 @@ bool InvalidateBlock(CValidationState& state, CBlockIndex *pindex) {
         // ActivateBestChain considers blocks already in chainActive
         // unconditionally valid already, so force disconnect away from it.
         if (!DisconnectTip(state)) {
+            mempool.removeForReorg(pcoinsTip, chainActive.Tip()->nHeight + 1);
             return false;
         }
     }
@@ -2779,6 +2788,7 @@ bool InvalidateBlock(CValidationState& state, CBlockIndex *pindex) {
     }
 
     InvalidChainFound(pindex);
+    mempool.removeForReorg(pcoinsTip, chainActive.Tip()->nHeight + 1);
     return true;
 }
 

src/main.h

@@ -514,7 +514,7 @@ bool InvalidateBlock(CValidationState& state, CBlockIndex *pindex);
 /** Remove invalidity status from a block and its descendants. */
 bool ReconsiderBlock(CValidationState& state, CBlockIndex *pindex);
 
-/** The currently-connected chain of blocks. */
+/** The currently-connected chain of blocks (protected by cs_main). */
 extern CChain chainActive;
 
 /** Global variable that points to the active CCoinsView (protected by cs_main) */