sqlpp11/transaction.h

/*
 * Copyright (c) 2013, Roland Bock
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 * 
 *   Redistributions of source code must retain the above copyright notice, this
 *   list of conditions and the following disclaimer.
 * 
 *   Redistributions in binary form must reproduce the above copyright notice, this
 *   list of conditions and the following disclaimer in the documentation and/or
 *   other materials provided with the distribution.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#ifndef SQLPP_TRANSACTION_H
#define SQLPP_TRANSACTION_H

#include <stdexcept>

namespace sqlpp
{
	static constexpr bool quiet_auto_rollback = false;
	static constexpr bool report_auto_rollback = true;

	template<typename Db>
	class transaction_t
	{
		Db& _db;
		const bool _report_unfinished_transaction;
		bool _finished = false;

	public:
		transaction_t(Db& db, bool report_unfinished_transaction):
			_db(db),
			_report_unfinished_transaction(report_unfinished_transaction)
		{
			_db.start_transaction();
		}

		transaction_t(const transaction_t&) = delete;
		transaction_t(transaction_t&&) = default;
		transaction_t& operator=(const transaction_t&) = delete;
		transaction_t& operator=(transaction_t&&) = delete;

		~transaction_t()
		{
			if (not _finished)
			{
				try
				{
					_db.rollback_transaction(_report_unfinished_transaction);
				}
				catch(const std::exception& e)
				{
					_db.report_rollback_failure(std::string("auto rollback failed: ") + e.what());
				}
				catch(...)
				{
					_db.report_rollback_failure("auto rollback failed with unknown exception");
				}
			}
		}

		void commit()
		{
			_finished = true;
			_db.commit_transaction();
		}

		void rollback()
		{
			_finished = true;
			_db.rollback_transaction(false);
		}
	};

	template<typename Db>
		transaction_t<typename std::decay<Db>::type> start_transaction(Db& db, bool report_unfinished_transaction = report_auto_rollback)
		{
			return { db, report_unfinished_transaction };
		};
}

#endif