wallettool: Optionally use BERKELEY_RO as format when dumping BDB wallets

In order to ease the transition to not having BDB, make the dump tool
use DatabaseFormmat::BERKELEY_RO when -withinternalbdb is set.

src/bitcoin-wallet.cpp

@@ -44,6 +44,7 @@ static void SetupWalletToolArgs(ArgsManager& argsman)
     argsman.AddArg("-legacy", "Create legacy wallet. Only for 'create'", ArgsManager::ALLOW_ANY, OptionsCategory::OPTIONS);
     argsman.AddArg("-format=<format>", "The format of the wallet file to create. Either \"bdb\" or \"sqlite\". Only used with 'createfromdump'", ArgsManager::ALLOW_ANY, OptionsCategory::OPTIONS);
     argsman.AddArg("-printtoconsole", "Send trace/debug info to console (default: 1 when no -debug is true, 0 otherwise).", ArgsManager::ALLOW_ANY, OptionsCategory::DEBUG_TEST);
+    argsman.AddArg("-withinternalbdb", "Use the internal Berkeley DB parser when dumping a Berkeley DB wallet file (default: false)", ArgsManager::ALLOW_ANY, OptionsCategory::DEBUG_TEST);
 
     argsman.AddCommand("info", "Get wallet info");
     argsman.AddCommand("create", "Create new wallet file");

src/wallet/dump.cpp

@@ -60,7 +60,13 @@ bool DumpWallet(const ArgsManager& args, WalletDatabase& db, bilingual_str& erro
     hasher << Span{line};
 
     // Write out the file format
-    line = strprintf("%s,%s\n", "format", db.Format());
+    std::string format = db.Format();
+    // BDB files that are opened using BerkeleyRODatabase have it's format as "bdb_ro"
+    // We want to override that format back to "bdb"
+    if (format == "bdb_ro") {
+        format = "bdb";
+    }
+    line = strprintf("%s,%s\n", "format", format);
     dump_file.write(line.data(), line.size());
     hasher << Span{line};
 

src/wallet/wallettool.cpp

@@ -194,6 +194,11 @@ bool ExecuteWalletToolFunc(const ArgsManager& args, const std::string& command)
         ReadDatabaseArgs(args, options);
         options.require_existing = true;
         DatabaseStatus status;
+
+        if (args.GetBoolArg("-withinternalbdb", false) && IsBDBFile(BDBDataFile(path))) {
+            options.require_format = DatabaseFormat::BERKELEY_RO;
+        }
+
         bilingual_str error;
         std::unique_ptr<WalletDatabase> database = MakeDatabase(path, options, status, error);
         if (!database) {

test/functional/test_runner.py

@@ -192,6 +192,7 @@ BASE_SCRIPTS = [
     'mempool_resurrect.py',
     'wallet_txn_doublespend.py --mineblock',
     'tool_wallet.py --legacy-wallet',
+    'tool_wallet.py --legacy-wallet --bdbro',
     'tool_wallet.py --descriptors',
     'tool_signet_miner.py --legacy-wallet',
     'tool_signet_miner.py --descriptors',

test/functional/tool_wallet.py

@@ -21,6 +21,7 @@ from test_framework.util import (
 class ToolWalletTest(BitcoinTestFramework):
     def add_options(self, parser):
         self.add_wallet_options(parser)
+        parser.add_argument("--bdbro", action="store_true", help="Use the BerkeleyRO internal parser when dumping a Berkeley DB wallet file")
 
     def set_test_params(self):
         self.num_nodes = 1
@@ -35,6 +36,8 @@ class ToolWalletTest(BitcoinTestFramework):
         default_args = ['-datadir={}'.format(self.nodes[0].datadir_path), '-chain=%s' % self.chain]
         if not self.options.descriptors and 'create' in args:
             default_args.append('-legacy')
+        if "dump" in args and self.options.bdbro:
+            default_args.append("-withinternalbdb")
 
         return subprocess.Popen([self.options.bitcoinwallet] + default_args + list(args), stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE, text=True)