/** Get the list of identified surrogates and their capabilities.
*
* This is based on the Surrogate-Capability header, but only includes the
* surrogates that followed the specification, ignoring any others.
* @return array The array of identified surrogates. Each element of this
* array is an associative array with the keys 'device-token' and
* 'capabilities', where 'capabilities' is an array of capability tokens
* for that device.
*/
private static function getSurrogates()
{
if (is_array(self::$surrogates)) {
return self::$surrogates;
}
self::$surrogates = array();
$header = self::getSurrogateCapabilityHeader();
if (is_string($header) && $header != '') {
$token = '[^\\0-\\037\\0177()<>@,;:\\"\\/[\\]?={} \\t]+';
$matches = array();
if (preg_match_all('/(?:^|,)\\s*(' . $token . ')="([^"]*)"\\s*(?=,|$)/', $header, $matches, PREG_SET_ORDER) > 0) {
foreach ($matches as $match) {
self::$surrogates[] = array('device-token' => $match[1], 'capabilities' => explode(' ', $match[2]));
}
}
}
return self::$surrogates;
}
