public function doUpgrade(&$context, Am_BatchProcessor $batch)
{
$session = $this->getSession();
if (empty($session->step)) {
$this->getSession()->step = 0;
}
do {
$currentOperation = $this->steps[$session->step][0];
$start = (int) @$session->start;
$this->outStepHeader();
$ret = call_user_func_array(array($this, $currentOperation), array($batch, &$start));
$session->start = $start;
if (!$ret) {
$batch->stop();
return false;
}
$this->outText(___('Done') . "<br />\n");
$session->step = $session->step + 1;
if ($session->step >= count($this->steps)) {
$session->unsetAll();
return true;
}
} while ($batch->checkLimits());
}