Add Unwrap method.

driver.go

@@ -56,6 +56,15 @@ func (d *impl) Open(name string) (driver.Conn, error) {
 	return &conn{c}, nil
 }
 
+// Unwrap gives access to underlying driver connection.
+func Unwrap(db *sql.DB) *Conn {
+	_, err := db.Exec("unwrap")
+	if cerr, ok := err.(*ConnError); ok {
+		return cerr.c
+	}
+	return nil
+}
+
 // PRAGMA schema_version may be used to detect when the database schema is altered
 
 func (c *conn) Exec(query string, args []driver.Value) (driver.Result, error) {

driver_test.go

@@ -6,8 +6,10 @@ package sqlite_test
 
 import (
 	"database/sql"
-	"github.com/bmizerany/assert"
 	"testing"
+
+	"github.com/bmizerany/assert"
+	"github.com/gwenn/gosqlite"
 )
 
 const (
@@ -162,3 +164,11 @@ func TestRowsWithStmtClosed(t *testing.T) {
 		checkNoError(t, err, "Error while scanning: %s")
 	}
 }
+
+func TestUnwrap(t *testing.T) {
+	db := sqlOpen(t)
+	conn := sqlite.Unwrap(db)
+	assert.Tf(t, conn != nil, "Expecting *sqlite.Conn but got %#v", conn)
+	// fmt.Printf("%#v\n", conn)
+	conn.TotalChanges()
+}