Allow to shut down during txdb upgrade

src/init.cpp

@@ -1358,7 +1358,7 @@ bool AppInitMain(boost::thread_group& threadGroup, CScheduler& scheduler)
     LogPrintf("* Using %.1fMiB for in-memory UTXO set (plus up to %.1fMiB of unused mempool space)\n", nCoinCacheUsage * (1.0 / 1024 / 1024), nMempoolSizeMax * (1.0 / 1024 / 1024));
 
     bool fLoaded = false;
-    while (!fLoaded) {
+    while (!fLoaded && !fRequestShutdown) {
         bool fReset = fReindex;
         std::string strLoadError;
 
@@ -1389,6 +1389,7 @@ bool AppInitMain(boost::thread_group& threadGroup, CScheduler& scheduler)
                         break;
                     }
                 }
+                if (fRequestShutdown) break;
 
                 if (!LoadBlockIndex(chainparams)) {
                     strLoadError = _("Error loading block database");
@@ -1466,7 +1467,7 @@ bool AppInitMain(boost::thread_group& threadGroup, CScheduler& scheduler)
             fLoaded = true;
         } while(false);
 
-        if (!fLoaded) {
+        if (!fLoaded && !fRequestShutdown) {
             // first suggest a reindex
             if (!fReset) {
                 bool fRet = uiInterface.ThreadSafeQuestion(

src/txdb.cpp

@@ -371,6 +371,9 @@ bool CCoinsViewDB::Upgrade() {
     CDBBatch batch(db);
     while (pcursor->Valid()) {
         boost::this_thread::interruption_point();
+        if (ShutdownRequested()) {
+            break;
+        }
         std::pair<unsigned char, uint256> key;
         if (pcursor->GetKey(key) && key.first == DB_COINS) {
             CCoins old_coins;