Kohana 3.3 ORM extension for safe database transactions

ORM.php

<?php defined('SYSPATH') OR die('No direct script access.');

class ORM extends Kohana_ORM {

	/**
	 * Set to true if you are creating a new transaction
	 * Set to false once you commit or rollback.
	 *
	 * @author Sigurdur
	 */
	protected $_transaction_active = false;

	/**
	 * Set the array containing the class and function name in an array
	 * of the transaction creator.
	 * Set to null once you commit or rollback.
	 *
	 * Example:
	 *  $_transaction_caller = ['class' = 'Model_Tours', 'function' = 'action_set_availability']
	 *
	 * @author Sigurdur
	 */
	protected $_transaction_caller = null;

	/**
	 * Set to true if you are creating a new transaction
	 * Set to false once you commit or rollback.
	 *
	 * @author Sigurdur
	 */

	protected $_transaction_rollback = false;
	/**
	 * True if a rollback situation is in progress
	 *
	 * @author  Sigurdur
	 * @return  void
	 */
	public function begin_transaction()
	{
		if (!$this->_transaction_active)
		{
			$backtrace = debug_backtrace(false, 2);
			Database::instance()->begin();
			$this->_transaction_active = true;
			$this->_transaction_rollback = false;
			$this->_transaction_caller = ['class' => $backtrace[1]['class'], 'function' => $backtrace[1]['function']];
		}
	}

	/**
	 * Commits a commit-safe DB transaction
	 * It is safe to call this function - you will not commit data unless the initial
	 * calling function is the one who started the transaction.
	 *
	 * @author  Sigurdur
	 * @return  void
	 */
	public function commit_transaction()
	{
		if ($this->_transaction_active)
		{
			$backtrace = debug_backtrace(false, 2);
			if ($this->_transaction_caller['class'] == $backtrace[1]['class'] && $this->_transaction_caller['function'] == $backtrace[1]['function'])
			{
				Database::instance()->commit();
				$this->_transaction_active = false;
				$this->_transaction_rollback = false;
				$this->_transaction_caller = null;
			}
		}
	}

	/**
	 * Rolls back a commit-safe DB transaction
	 * It is safe to call this function - you will not commit data unless the initial
	 * calling function is the one who started the transaction.
	 *
	 * Please note that you need to make sure to rollback the transaction from
	 * the original calling function. Otherwise the transaction is not rolled back.
	 *
	 * @author  Sigurdur
	 * @return  void
	 */
	public function rollback_transaction()
	{
		if ($this->_transaction_active)
		{
			Database::instance()->rollback();
			$this->_transaction_active = false;
			$this->_transaction_rollback = true;
			$this->_transaction_caller = null;
		}
	}
}