Unserializes menu data, using a map to replace path elements.
The menu system stores various path-related information (such as the 'page arguments' and 'access arguments' components of a menu item) in the database using serialized arrays, where integer values in the arrays represent arguments to be replaced by values from the path. This function first unserializes such menu information arrays, and then does the path replacement.
The path replacement acts on each integer-valued element of the unserialized menu data array ($data) using a map array ($map, which is typically an array of path arguments) as a list of replacements. For instance, if there is an element of $data whose value is the number 2, then it is replaced in $data with $map[2]; non-integer values in $data are left alone.
As an example, an unserialized $data array with elements ('node_load', 1) represents instructions for calling the node_load() function. Specifically, this instruction says to use the path component at index 1 as the input parameter to node_load(). If the path is 'node/123', then $map will be the array ('node', 123), and the returned array from this function will have elements ('node_load', 123), since $map[1] is 123. This return value will indicate specifically that node_load(123) is to be called to load the node whose ID is 123 for this menu item.
$data: A serialized array of menu data, as read from the database.
$map: A path argument array, used to replace integer values in $data; an integer value N in $data will be replaced by value $map[N]. Typically, the $map array is generated from a call to the arg() function.
The unserialized $data array, with path arguments replaced.
function menu_unserialize($data, $map) {
if ($data = unserialize($data)) {
foreach ($data as $k => $v) {
if (is_int($v)) {
$data[$k] = isset($map[$v]) ? $map[$v] : '';
}
}
return $data;
}
else {
return array();
}
}