destroy config when closing database

DuckDB destroys config when closing database. e.g. here https://github.com/duckdb/duckdb/blob/b58f184e1e87df5fc2d574996a6b63409df96f47/src/common/adbc/adbc.cpp#L218-L228

duckdb.go

@@ -52,6 +52,8 @@ func NewConnector(dsn string, connInitFn func(execer driver.ExecerContext) error
 	connectionString := C.CString(extractConnectionString(dsn))
 	defer C.free(unsafe.Pointer(connectionString))
 
+	connector := &Connector{db: &db, connInitFn: connInitFn}
+
 	// Check for config options.
 	if len(parsedDSN.RawQuery) == 0 {
 		var errMsg *C.char
@@ -66,10 +68,14 @@ func NewConnector(dsn string, connInitFn func(execer driver.ExecerContext) error
 			return nil, err
 		}
 
+		connector.config = config
+
 		var errMsg *C.char
 		defer C.duckdb_free(unsafe.Pointer(errMsg))
 
 		if state := C.duckdb_open_ext(connectionString, &db, config, &errMsg); state == C.DuckDBError {
+			C.duckdb_destroy_config(&config)
+
 			return nil, fmt.Errorf("%w: %s", errOpen, C.GoString(errMsg))
 		}
 	}
@@ -79,6 +85,7 @@ func NewConnector(dsn string, connInitFn func(execer driver.ExecerContext) error
 
 type Connector struct {
 	db         *C.duckdb_database
+	config     C.duckdb_config
 	connInitFn func(execer driver.ExecerContext) error
 }
 
@@ -107,6 +114,10 @@ func (c *Connector) Connect(context.Context) (driver.Conn, error) {
 func (c *Connector) Close() error {
 	C.duckdb_close(c.db)
 	c.db = nil
+
+	C.duckdb_destroy_config(c.config)
+	c.config = nil
+
 	return nil
 }
 
@@ -115,6 +126,7 @@ func extractConnectionString(dataSourceName string) string {
 	if queryIndex < 0 {
 		queryIndex = len(dataSourceName)
 	}
+
 	return dataSourceName[0:queryIndex]
 }
 
@@ -127,6 +139,8 @@ func prepareConfig(options map[string][]string) (C.duckdb_config, error) {
 	for k, v := range options {
 		if len(v) > 0 {
 			if err := setConfig(config, k, v[0]); err != nil {
+				C.duckdb_destroy_config(&config)
+
 				return nil, err
 			}
 		}