lib/htmlpurifier/HTMLPurifier/ChildDef/Custom.php

   1 <?php
   2
   3 require_once 'HTMLPurifier/ChildDef.php';
   4
   5 /**
   6  * Custom validation class, accepts DTD child definitions
   7  *
   8  * @warning Currently this class is an all or nothing proposition, that is,
   9  *          it will only give a bool return value.
  10  * @note This class is currently not used by any code, although it is unit
  11  *       tested.
  12  */
  13 class HTMLPurifier_ChildDef_Custom extends HTMLPurifier_ChildDef
  14 {
  15     var $type = 'custom';
  16     var $allow_empty = false;
  17     /**
  18      * Allowed child pattern as defined by the DTD
  19      */
  20     var $dtd_regex;
  21     /**
  22      * PCRE regex derived from $dtd_regex
  23      * @private
  24      */
  25     var $_pcre_regex;
  26     /**
  27      * @param $dtd_regex Allowed child pattern from the DTD
  28      */
  29     function HTMLPurifier_ChildDef_Custom($dtd_regex) {
  30         $this->dtd_regex = $dtd_regex;
  31         $this->_compileRegex();
  32     }
  33     /**
  34      * Compiles the PCRE regex from a DTD regex ($dtd_regex to $_pcre_regex)
  35      */
  36     function _compileRegex() {
  37         $raw = str_replace(' ', '', $this->dtd_regex);
  38         if ($raw{0} != '(') {
  39             $raw = "($raw)";
  40         }
  41         $reg = str_replace(',', ',?', $raw);
  42         $reg = preg_replace('/([#a-zA-Z0-9_.-]+)/', '(,?\\0)', $reg);
  43         $this->_pcre_regex = $reg;
  44     }
  45     function validateChildren($tokens_of_children, $config, &$context) {
  46         $list_of_children = '';
  47         $nesting = 0; // depth into the nest
  48         foreach ($tokens_of_children as $token) {
  49             if (!empty($token->is_whitespace)) continue;
  50
  51             $is_child = ($nesting == 0); // direct
  52
  53             if ($token->type == 'start') {
  54                 $nesting++;
  55             } elseif ($token->type == 'end') {
  56                 $nesting--;
  57             }
  58
  59             if ($is_child) {
  60                 $list_of_children .= $token->name . ',';
  61             }
  62         }
  63         $list_of_children = rtrim($list_of_children, ',');
  64
  65         $okay =
  66             preg_match(
  67                 '/^'.$this->_pcre_regex.'$/',
  68                 $list_of_children
  69             );
  70
  71         return (bool) $okay;
  72     }
  73 }
  74
  75 ?>