database: create directory path for ring.db

On Windows, database file creation fails if any folders of its path
isn't already existing. This small patch ensures this is done before
attempting to open ring.db

Change-Id: I545a7b4ac0015a62a4e36553df997e7d229243a5
Reviewed-by: Sébastien Blin <sebastien.blin@savoirfairelinux.com>

src/database.cpp

@@ -31,6 +31,7 @@
 #include <QtSql/QSqlRecord>
 #include <QtCore/QStandardPaths>
 #include <QtCore/QVariant>
+#include <QDir>
 
 // Std
 #include <sstream>
@@ -59,6 +60,12 @@ Database::Database()
         throw std::runtime_error("QSQLITE not supported");
     }
 
+    {
+        // create data directory if not created yet
+        QDir dataDir;
+        dataDir.mkpath(QStandardPaths::writableLocation(QStandardPaths::DataLocation));
+    }
+
     // initalize the database.
     db_ = QSqlDatabase::addDatabase("QSQLITE");
 #ifdef ENABLE_TEST