friendica_2021-01/library/HTMLPurifier/AttrDef/HTML/Nmtokens.php

52 lines
1.6 KiB
PHP
Executable file

<?php
/**
* Validates contents based on NMTOKENS attribute type.
*/
class HTMLPurifier_AttrDef_HTML_Nmtokens extends HTMLPurifier_AttrDef
{
public function validate($string, $config, $context) {
$string = trim($string);
// early abort: '' and '0' (strings that convert to false) are invalid
if (!$string) return false;
$tokens = $this->split($string, $config, $context);
$tokens = $this->filter($tokens, $config, $context);
if (empty($tokens)) return false;
return implode(' ', $tokens);
}
/**
* Splits a space separated list of tokens into its constituent parts.
*/
protected function split($string, $config, $context) {
// OPTIMIZABLE!
// do the preg_match, capture all subpatterns for reformulation
// we don't support U+00A1 and up codepoints or
// escaping because I don't know how to do that with regexps
// and plus it would complicate optimization efforts (you never
// see that anyway).
$pattern = '/(?:(?<=\s)|\A)'. // look behind for space or string start
'((?:--|-?[A-Za-z_])[A-Za-z_\-0-9]*)'.
'(?:(?=\s)|\z)/'; // look ahead for space or string end
preg_match_all($pattern, $string, $matches);
return $matches[1];
}
/**
* Template method for removing certain tokens based on arbitrary criteria.
* @note If we wanted to be really functional, we'd do an array_filter
* with a callback. But... we're not.
*/
protected function filter($tokens, $config, $context) {
return $tokens;
}
}
// vim: et sw=4 sts=4