Add option to disable automatic resending of txs

This option can disable automatic resending of txs. It defaults to the
normal behavior of resending txs automatically and resending can be disabled
with -resendtx=0 .

This is not intended for normal usage and is undocumented for now. It is
useful for devs who are debugging internals and also when rescanning large
wallets. We seem to have either some bugs and/or performance problems when
rescanning wallets with many txs.

src/validationinterface.cpp

@@ -32,7 +32,13 @@ void RegisterValidationInterface(CValidationInterface* pwalletIn) {
     g_signals.UpdatedTransaction.connect(boost::bind(&CValidationInterface::UpdatedTransaction, pwalletIn, _1));
     g_signals.ChainTip.connect(boost::bind(&CValidationInterface::ChainTip, pwalletIn, _1, _2, _3));
     g_signals.SetBestChain.connect(boost::bind(&CValidationInterface::SetBestChain, pwalletIn, _1));
-    g_signals.Broadcast.connect(boost::bind(&CValidationInterface::ResendWalletTransactions, pwalletIn, _1));
+
+    if(GetArg("-resendtx", true)) {
+        g_signals.Broadcast.connect(boost::bind(&CValidationInterface::ResendWalletTransactions, pwalletIn, _1));
+    } else {
+        LogPrintf("%s: automatic resending of wallet transactions disabled\n", __func__);
+    }
+
     g_signals.BlockChecked.connect(boost::bind(&CValidationInterface::BlockChecked, pwalletIn, _1, _2));
     //g_signals.ScriptForMining.connect(boost::bind(&CValidationInterface::GetScriptForMining, pwalletIn, _1));
 }
@@ -40,7 +46,9 @@ void RegisterValidationInterface(CValidationInterface* pwalletIn) {
 void UnregisterValidationInterface(CValidationInterface* pwalletIn) {
     //g_signals.ScriptForMining.disconnect(boost::bind(&CValidationInterface::GetScriptForMining, pwalletIn, _1));
     g_signals.BlockChecked.disconnect(boost::bind(&CValidationInterface::BlockChecked, pwalletIn, _1, _2));
-    g_signals.Broadcast.disconnect(boost::bind(&CValidationInterface::ResendWalletTransactions, pwalletIn, _1));
+    if(GetArg("-resendtx", true)) {
+        g_signals.Broadcast.disconnect(boost::bind(&CValidationInterface::ResendWalletTransactions, pwalletIn, _1));
+    }
     g_signals.ChainTip.disconnect(boost::bind(&CValidationInterface::ChainTip, pwalletIn, _1, _2, _3));
     g_signals.SetBestChain.disconnect(boost::bind(&CValidationInterface::SetBestChain, pwalletIn, _1));
     g_signals.UpdatedTransaction.disconnect(boost::bind(&CValidationInterface::UpdatedTransaction, pwalletIn, _1));