Report the status of indexing.
The core search module only invokes this hook on active modules. Implementing modules do not need to check whether they are active when calculating their return values.
An associative array with the key-value pairs:
function hook_search_status() {
$total = db_query('SELECT COUNT(*) FROM {node} WHERE status = 1')
->fetchField();
$remaining = db_query("SELECT COUNT(*) FROM {node} n LEFT JOIN {search_dataset} d ON d.type = 'node' AND d.sid = n.nid WHERE n.status = 1 AND d.sid IS NULL OR d.reindex <> 0")
->fetchField();
return array(
'remaining' => $remaining,
'total' => $total,
);
}