Repository: bitcoin/bitcoin
File: src/init.cpp (C++)

Code before:
    CTxMemPool::Options mempool_opts{
        .check_ratio = chainparams.DefaultConsistencyChecks() ? 1 : 0,
        .signals = &validation_signals,
    };
    auto result{ApplyArgsManOptions(args, chainparams, mempool_opts)};
    if (!result) {
        return InitError(util::ErrorString(result));
    }

    bool do_reindex{args.GetBoolArg("-reindex", false)};
    const bool do_reindex_chainstate{args.GetBoolArg("-reindex-chainstate", false)};

    for (bool fLoaded = false; !fLoaded && !ShutdownRequested(node);) {
        bilingual_str mempool_error;
        node.mempool = std::make_unique<CTxMemPool>(mempool_opts, mempool_error);
        if (!mempool_error.empty()) {
            return InitError(mempool_error);
        }
        LogPrintf("* Using %.1f MiB for in-memory UTXO set (plus up to %.1f MiB of unused mempool space)\n", cache_sizes.coins * (1.0 / 1024 / 1024), mempool_opts.max_size_bytes * (1.0 / 1024 / 1024));

        blockman_opts.wipe_block_tree_db = do_reindex;

        try {
            node.chainman = std::make_unique<ChainstateManager>(*Assert(node.shutdown), chainman_opts, blockman_opts);
        } catch (dbwrapper_error&) {
            return InitError(Untranslated("Error opening block database."));
        } catch (std::exception& e) {
            return InitError(strprintf(Untranslated("Failed to initialize ChainstateManager: %s"), e.what()));
        }
        ChainstateManager& chainman = *node.chainman;

        // This is defined and set here instead of inline in validation.h to avoid a hard
        // dependency between validation and index/base, since the latter is not in
        // libbitcoinkernel.
        chainman.snapshot_download_completed = [&node]() {
            if (!node.chainman->m_blockman.IsPruneMode()) {
                LogPrintf("[snapshot] re-enabling NODE_NETWORK services\n");
                node.connman->AddLocalServices(NODE_NETWORK);
            }

            LogPrintf("[snapshot] restarting indexes\n");

            // Drain the validation interface queue to ensure that the old indexes
            // don't have any pending work.
            Assert(node.validation_signals)->SyncWithValidationInterfaceQueue();

            for (auto* index : node.indexes) {
                index->Interrupt();
                index->Stop();
                if (!(index->Init() && index->StartBackgroundSync())) {
                    LogPrintf("[snapshot] WARNING failed to restart index %s on snapshot chain\n", index->GetName());

Review comment (suggestion):
This changes the error handling if the block tree db is corrupted as a side effect. Before, we'd get the advice "Please restart with -reindex or -reindex-chainstate to recover." on the console, and, if using the GUI, the option to reindex by clicking a button. Now we just get an "Error opening block database" error on both without any advice how to fix it.

I'm not sure if the GUI one-click reindex option is totally essential, but in my opinion we should at least keep the advice to reindex, and also show it in the GUI.

Code after:
        SetProxy(NET_IPV4, addrProxy);
        SetProxy(NET_IPV6, addrProxy);
        SetProxy(NET_CJDNS, addrProxy);
        SetNameProxy(addrProxy);
        onion_proxy = addrProxy;
    }

    const bool onlynet_used_with_onion{args.IsArgSet("-onlynet") && g_reachable_nets.Contains(NET_ONION)};

    // -onion can be used to set only a proxy for .onion, or override normal proxy for .onion addresses
    // -noonion (or -onion=0) disables connecting to .onion entirely
    // An empty string is used to not override the onion proxy (in which case it defaults to -proxy set above, or none)
    std::string onionArg = args.GetArg("-onion", "");
    if (onionArg != "") {
        if (onionArg == "0") { // Handle -noonion/-onion=0
            onion_proxy = Proxy{};
            if (onlynet_used_with_onion) {
                return InitError(
                    _("Outbound connections restricted to Tor (-onlynet=onion) but the proxy for "
                      "reaching the Tor network is explicitly forbidden: -onion=0"));
            }
        } else {
            if (IsUnixSocketPath(onionArg)) {
                onion_proxy = Proxy(onionArg, proxyRandomize);
            } else {
                const std::optional<CService> addr{Lookup(onionArg, 9050, fNameLookup)};
                if (!addr.has_value() || !addr->IsValid()) {
                    return InitError(strprintf(_("Invalid -onion address or hostname: '%s'"), onionArg));
                }

                onion_proxy = Proxy(addr.value(), proxyRandomize);
            }
        }
    }

    if (onion_proxy.IsValid()) {
        SetProxy(NET_ONION, onion_proxy);
    } else {
        // If -listenonion is set, then we will (try to) connect to the Tor control port
        // later from the torcontrol thread and may retrieve the onion proxy from there.
        const bool listenonion_disabled{!args.GetBoolArg("-listenonion", DEFAULT_LISTEN_ONION)};
        if (onlynet_used_with_onion && listenonion_disabled) {
            return InitError(
                _("Outbound connections restricted to Tor (-onlynet=onion) but the proxy for "
                  "reaching the Tor network is not provided: none of -proxy, -onion or "
                  "-listenonion is given"));
        }
        g_reachable_nets.Remove(NET_ONION);
    }

    for (const std::string& strAddr : args.GetArgs("-externalip")) {