Add LMDB upgrade to v22: Clear unchecked table

In pull request #4021 the binary representation of `unchecked_info` was
changed. We have to clear the unchecked table, because the new binary
format is not compatible with the old one.

This commit only clears the unchecked table for the LMDB implementation.
The RocksDB implementation doesn't have an upgrade mechanism yet.

nano/core_test/block_store.cpp

@@ -2434,6 +2434,36 @@ namespace lmdb
 		auto transaction (store.tx_begin_read ());
 		ASSERT_LT (19, store.version.get (transaction));
 	}
+
+	TEST (mdb_block_store, upgrade_v21_v22)
+	{
+		if (nano::rocksdb_config::using_rocksdb_in_tests ())
+		{
+			// Don't test this in rocksdb mode
+			return;
+		}
+		auto path (nano::unique_path ());
+		nano::logger_mt logger;
+		nano::stats stats;
+		{
+			nano::lmdb::store store (logger, path, nano::dev::constants);
+			nano::ledger ledger (store, stats, nano::dev::constants);
+			auto transaction (store.tx_begin_write ());
+			store.initialize (transaction, ledger.cache, ledger.constants);
+			// Add data to unchecked store
+			store.unchecked_store.put (transaction, nano::dev::genesis->hash (), nano::unchecked_info{ nano::dev::genesis });
+			store.version.put (transaction, 21);
+			ASSERT_EQ (1, store.unchecked_store.count (transaction));
+		}
+		// Upgrading should clear the unchecked table
+		nano::lmdb::store store (logger, path, nano::dev::constants);
+		ASSERT_FALSE (store.init_error ());
+		auto transaction (store.tx_begin_read ());
+		ASSERT_EQ (0, store.unchecked_store.count (transaction));
+
+		// Version should be correct
+		ASSERT_LT (21, store.version.get (transaction));
+	}
 }
 }
 

nano/node/lmdb/lmdb.cpp

@@ -304,6 +304,9 @@ bool nano::lmdb::store::do_upgrades (nano::write_transaction & transaction_a, na
 			upgrade_v20_to_v21 (transaction_a);
 			[[fallthrough]];
 		case 21:
+			upgrade_v21_to_v22 (transaction_a);
+			[[fallthrough]];
+		case 22:
 			break;
 		default:
 			logger.always_log (boost::str (boost::format ("The version of the ledger (%1%) is too high for this node") % version_l));
@@ -777,6 +780,18 @@ void nano::lmdb::store::upgrade_v20_to_v21 (nano::write_transaction const & tran
 	logger.always_log ("Finished creating new final_vote table");
 }
 
+void nano::lmdb::store::upgrade_v21_to_v22 (nano::write_transaction const & transaction_a)
+{
+	// In the following pull request the binary representation of `unchecked_info` was changed:
+	// https://github.com/nanocurrency/nano-node/pull/4021
+	// We have to clear the unchecked table, because the new binary format is not compatible with
+	// the old one.
+	logger.always_log ("Preparing v21 to v22 database upgrade...");
+	mdb_drop (env.tx (transaction_a), unchecked_store.unchecked_handle, 0);
+	version.put (transaction_a, 22);
+	logger.always_log ("Finished clearing unchecked table");
+}
+
 /** Takes a filepath, appends '_backup_<timestamp>' to the end (but before any extension) and saves that file in the same directory */
 void nano::lmdb::store::create_backup_file (nano::mdb_env & env_a, boost::filesystem::path const & filepath_a, nano::logger_mt & logger_a)
 {

nano/node/lmdb/lmdb.hpp

@@ -136,6 +136,7 @@ namespace lmdb
 		void upgrade_v18_to_v19 (nano::write_transaction const &);
 		void upgrade_v19_to_v20 (nano::write_transaction const &);
 		void upgrade_v20_to_v21 (nano::write_transaction const &);
+		void upgrade_v21_to_v22 (nano::write_transaction const &);
 
 		std::shared_ptr<nano::block> block_get_v18 (nano::transaction const & transaction_a, nano::block_hash const & hash_a) const;
 		nano::mdb_val block_raw_get_v18 (nano::transaction const & transaction_a, nano::block_hash const & hash_a, nano::block_type & type_a) const;
@@ -188,6 +189,7 @@ namespace lmdb
 		friend class mdb_block_store_upgrade_v18_v19_Test;
 		friend class mdb_block_store_upgrade_v19_v20_Test;
 		friend class mdb_block_store_upgrade_v20_v21_Test;
+		friend class mdb_block_store_upgrade_v21_v22_Test;
 		friend class block_store_DISABLED_change_dupsort_Test;
 		friend void write_sideband_v14 (nano::lmdb::store &, nano::transaction &, nano::block const &, MDB_dbi);
 		friend void write_sideband_v15 (nano::lmdb::store &, nano::transaction &, nano::block const &);

nano/secure/store.hpp

@@ -828,6 +828,7 @@ class unchecked_map;
 class store
 {
 	friend class rocksdb_block_store_tombstone_count_Test;
+	friend class mdb_block_store_upgrade_v21_v22_Test;
 
 public:
 	// clang-format off
@@ -859,7 +860,7 @@ class store
 	account_store & account;
 	pending_store & pending;
 	static int constexpr version_minimum{ 14 };
-	static int constexpr version_current{ 21 };
+	static int constexpr version_current{ 22 };
 
 private:
 	unchecked_store & unchecked;