library/HTMLPurifier/ChildDef/Required.php

   1 <?php
   2
   3 /**
   4  * Definition that allows a set of elements, but disallows empty children.
   5  */
   6 class HTMLPurifier_ChildDef_Required extends HTMLPurifier_ChildDef
   7 {
   8     /**
   9      * Lookup table of allowed elements.
  10      * @public
  11      */
  12     public $elements = array();
  13     /**
  14      * Whether or not the last passed node was all whitespace.
  15      */
  16     protected $whitespace = false;
  17     /**
  18      * @param $elements List of allowed element names (lowercase).
  19      */
  20     public function __construct($elements) {
  21         if (is_string($elements)) {
  22             $elements = str_replace(' ', '', $elements);
  23             $elements = explode('|', $elements);
  24         }
  25         $keys = array_keys($elements);
  26         if ($keys == array_keys($keys)) {
  27             $elements = array_flip($elements);
  28             foreach ($elements as $i => $x) {
  29                 $elements[$i] = true;
  30                 if (empty($i)) unset($elements[$i]); // remove blank
  31             }
  32         }
  33         $this->elements = $elements;
  34     }
  35     public $allow_empty = false;
  36     public $type = 'required';
  37     public function validateChildren($tokens_of_children, $config, $context) {
  38         // Flag for subclasses
  39         $this->whitespace = false;
  40
  41         // if there are no tokens, delete parent node
  42         if (empty($tokens_of_children)) return false;
  43
  44         // the new set of children
  45         $result = array();
  46
  47         // current depth into the nest
  48         $nesting = 0;
  49
  50         // whether or not we're deleting a node
  51         $is_deleting = false;
  52
  53         // whether or not parsed character data is allowed
  54         // this controls whether or not we silently drop a tag
  55         // or generate escaped HTML from it
  56         $pcdata_allowed = isset($this->elements['#PCDATA']);
  57
  58         // a little sanity check to make sure it's not ALL whitespace
  59         $all_whitespace = true;
  60
  61         // some configuration
  62         $escape_invalid_children = $config->get('Core.EscapeInvalidChildren');
  63
  64         // generator
  65         $gen = new HTMLPurifier_Generator($config, $context);
  66
  67         foreach ($tokens_of_children as $token) {
  68             if (!empty($token->is_whitespace)) {
  69                 $result[] = $token;
  70                 continue;
  71             }
  72             $all_whitespace = false; // phew, we're not talking about whitespace
  73
  74             $is_child = ($nesting == 0);
  75
  76             if ($token instanceof HTMLPurifier_Token_Start) {
  77                 $nesting++;
  78             } elseif ($token instanceof HTMLPurifier_Token_End) {
  79                 $nesting--;
  80             }
  81
  82             if ($is_child) {
  83                 $is_deleting = false;
  84                 if (!isset($this->elements[$token->name])) {
  85                     $is_deleting = true;
  86                     if ($pcdata_allowed && $token instanceof HTMLPurifier_Token_Text) {
  87                         $result[] = $token;
  88                     } elseif ($pcdata_allowed && $escape_invalid_children) {
  89                         $result[] = new HTMLPurifier_Token_Text(
  90                             $gen->generateFromToken($token)
  91                         );
  92                     }
  93                     continue;
  94                 }
  95             }
  96             if (!$is_deleting || ($pcdata_allowed && $token instanceof HTMLPurifier_Token_Text)) {
  97                 $result[] = $token;
  98             } elseif ($pcdata_allowed && $escape_invalid_children) {
  99                 $result[] =
 100                     new HTMLPurifier_Token_Text(
 101                         $gen->generateFromToken($token)
 102                     );
 103             } else {
 104                 // drop silently
 105             }
 106         }
 107         if (empty($result)) return false;
 108         if ($all_whitespace) {
 109             $this->whitespace = true;
 110             return false;
 111         }
 112         if ($tokens_of_children == $result) return true;
 113         return $result;
 114     }
 115 }
 116
 117 // vim: et sw=4 sts=4