init: Stop indexes on shutdown after ChainStateFlushed callback.

Currently, the latest index state may not be committed to disk on shutdown.

Author: jimpo

src/init.cpp

@@ -197,8 +197,6 @@ void Shutdown(NodeContext& node)
     // using the other before destroying them.
     if (node.peer_logic) UnregisterValidationInterface(node.peer_logic.get());
     if (node.connman) node.connman->Stop();
-    if (g_txindex) g_txindex->Stop();
-    ForEachBlockFilterIndex([](BlockFilterIndex& index) { index.Stop(); });
 
     StopTorControl();
 
@@ -212,8 +210,6 @@ void Shutdown(NodeContext& node)
     node.peer_logic.reset();
     node.connman.reset();
     node.banman.reset();
-    g_txindex.reset();
-    DestroyAllBlockFilterIndexes();
 
     if (::mempool.IsLoaded() && gArgs.GetArg("-persistmempool", DEFAULT_PERSIST_MEMPOOL)) {
         DumpMempool(::mempool);
@@ -246,6 +242,14 @@ void Shutdown(NodeContext& node)
     // CValidationInterface callbacks, flush them...
     GetMainSignals().FlushBackgroundCallbacks();
 
+    // Stop and delete all indexes only after flushing background callbacks.
+    if (g_txindex) {
+        g_txindex->Stop();
+        g_txindex.reset();
+    }
+    ForEachBlockFilterIndex([](BlockFilterIndex& index) { index.Stop(); });
+    DestroyAllBlockFilterIndexes();
+
     // Any future callbacks will be dropped. This should absolutely be safe - if
     // missing a callback results in an unrecoverable situation, unclean shutdown
     // would too. The only reason to do the above flushes is to let the wallet catch