/*
Copyright (C) 2012, University of Cambridge, Department of Psychiatry.
Created by Rudolf Cardinal (rnc1001@cam.ac.uk).
This file is part of CamCOPS.
CamCOPS is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
CamCOPS is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with CamCOPS. If not, see <https://www.gnu.org/licenses/>.
*/
#pragma once
#include <QString>
class DatabaseManager;
// Represents an SQL transaction that can be nested, using
// SAVEPOINT name;
// RELEASE name; -- on success
// ROLLBACK TO SAVEPOINT name; -- on failure
class DbNestableTransaction
{
// https://www.sqlite.org/lang_savepoint.html
public:
// Create the transaction. It starts in a "successful" state.
DbNestableTransaction(DatabaseManager& db);
// When the transaction is destroyed, it releases or rolls back depending
// on whether it's been told of failure or not.
~DbNestableTransaction();
// Mark the transaction as a failure.
void fail();
// Mark the transaction as successful.
void succeed();
protected:
// Our database manager.
DatabaseManager& m_db;
// Have we failed?
bool m_fail;
// What's our SAVEPOINT name?
QString m_name;
// Used for the savepoint name; continuously increments
static int s_count;
// Current depth within savepoint stack
static int s_level;
};