fix txindex inconsistency if twisterd crashes.

txindex (user,-1) may point to a key in a block not yet linked to the chain.

src/main.cpp

@@ -709,7 +709,7 @@ bool GetTransaction(const std::string &username, CTransaction &txOut, uint256 &h
     return false;
 }
 
-bool verifyDuplicateOrReplacementTx(CTransaction &tx, bool checkDuplicate, bool checkReplacement, int maxHeight)
+bool verifyDuplicateOrReplacementTx(CTransaction &tx, bool checkDuplicate, bool checkReplacement, int maxHeight, bool removeOrphan)
 {
     CTransaction oldTx;
     uint256 hashBlock;
@@ -740,6 +740,14 @@ bool verifyDuplicateOrReplacementTx(CTransaction &tx, bool checkDuplicate, bool
                 return true;
             }
         }
+    } else if (removeOrphan) {
+        // check if (user,-1) exists in txindex and remove it
+        // return true to count as duplicate/replacement
+        uint256 txid = SerializeHash(make_pair(tx.GetUsername(),-1));
+        if( pblocktree->HaveTxIndex(txid) ) {
+            pblocktree->EraseTxIndex(txid);
+            return true;
+        }
     }
     return false;
 }
@@ -1154,7 +1162,7 @@ bool ConnectBlock(CBlock& block, CValidationState& state, CBlockIndex* pindex, C
              *    reconnect blocks which transactions are already written to the tx index.
              * 2) possibly a key replacement. check if new key is signed by the old one.
              */
-            if( !verifyDuplicateOrReplacementTx(tx, true, true, block.nHeight) ) {
+            if( !verifyDuplicateOrReplacementTx(tx, true, true, block.nHeight, true) ) {
                 // not the same, not replacement => error!
                 return state.DoS(100, error("ConnectBlock() : tried to overwrite transaction"));
             }

src/main.h

@@ -184,7 +184,7 @@ std::string GetWarnings(std::string strFor);
 /** Retrieve a transaction (from memory pool, or from disk, if possible) */
 bool GetTransaction(const std::string &username, CTransaction &tx, uint256 &hashBlock, int maxHeight = -1);
 /** Verify duplicate or replacement transactions */
-bool verifyDuplicateOrReplacementTx(CTransaction &tx, bool checkDuplicate, bool checkReplacement, int maxHeight = -1);
+bool verifyDuplicateOrReplacementTx(CTransaction &tx, bool checkDuplicate, bool checkReplacement, int maxHeight = -1, bool removeOrphan = false);
 /** Connect/disconnect blocks until pindexNew is the new tip of the active block chain */
 bool SetBestChain(CValidationState &state, CBlockIndex* pindexNew);
 /** Find the best known block, and make it the tip of the block chain */