74 lines
2.1 KiB
PHP
74 lines
2.1 KiB
PHP
<?php
|
|
|
|
/**
|
|
* Validates the HTML attribute lang, effectively a language code.
|
|
* @note Built according to RFC 3066, which obsoleted RFC 1766
|
|
*/
|
|
class HTMLPurifier_AttrDef_Lang extends HTMLPurifier_AttrDef
|
|
{
|
|
|
|
public function validate($string, $config, $context) {
|
|
|
|
$string = trim($string);
|
|
if (!$string) return false;
|
|
|
|
$subtags = explode('-', $string);
|
|
$num_subtags = count($subtags);
|
|
|
|
if ($num_subtags == 0) return false; // sanity check
|
|
|
|
// process primary subtag : $subtags[0]
|
|
$length = strlen($subtags[0]);
|
|
switch ($length) {
|
|
case 0:
|
|
return false;
|
|
case 1:
|
|
if (! ($subtags[0] == 'x' || $subtags[0] == 'i') ) {
|
|
return false;
|
|
}
|
|
break;
|
|
case 2:
|
|
case 3:
|
|
if (! ctype_alpha($subtags[0]) ) {
|
|
return false;
|
|
} elseif (! ctype_lower($subtags[0]) ) {
|
|
$subtags[0] = strtolower($subtags[0]);
|
|
}
|
|
break;
|
|
default:
|
|
return false;
|
|
}
|
|
|
|
$new_string = $subtags[0];
|
|
if ($num_subtags == 1) return $new_string;
|
|
|
|
// process second subtag : $subtags[1]
|
|
$length = strlen($subtags[1]);
|
|
if ($length == 0 || ($length == 1 && $subtags[1] != 'x') || $length > 8 || !ctype_alnum($subtags[1])) {
|
|
return $new_string;
|
|
}
|
|
if (!ctype_lower($subtags[1])) $subtags[1] = strtolower($subtags[1]);
|
|
|
|
$new_string .= '-' . $subtags[1];
|
|
if ($num_subtags == 2) return $new_string;
|
|
|
|
// process all other subtags, index 2 and up
|
|
for ($i = 2; $i < $num_subtags; $i++) {
|
|
$length = strlen($subtags[$i]);
|
|
if ($length == 0 || $length > 8 || !ctype_alnum($subtags[$i])) {
|
|
return $new_string;
|
|
}
|
|
if (!ctype_lower($subtags[$i])) {
|
|
$subtags[$i] = strtolower($subtags[$i]);
|
|
}
|
|
$new_string .= '-' . $subtags[$i];
|
|
}
|
|
|
|
return $new_string;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
// vim: et sw=4 sts=4
|