library/HTMLPurifier/ElementDef.php

   1 <?php
   2
   3 /**
   4  * Structure that stores an HTML element definition. Used by
   5  * HTMLPurifier_HTMLDefinition and HTMLPurifier_HTMLModule.
   6  * @note This class is inspected by HTMLPurifier_Printer_HTMLDefinition.
   7  *       Please update that class too.
   8  */
   9 class HTMLPurifier_ElementDef
  10 {
  11
  12     /**
  13      * Does the definition work by itself, or is it created solely
  14      * for the purpose of merging into another definition?
  15      */
  16     public $standalone = true;
  17
  18     /**
  19      * Associative array of attribute name to HTMLPurifier_AttrDef
  20      * @note Before being processed by HTMLPurifier_AttrCollections
  21      *       when modules are finalized during
  22      *       HTMLPurifier_HTMLDefinition->setup(), this array may also
  23      *       contain an array at index 0 that indicates which attribute
  24      *       collections to load into the full array. It may also
  25      *       contain string indentifiers in lieu of HTMLPurifier_AttrDef,
  26      *       see HTMLPurifier_AttrTypes on how they are expanded during
  27      *       HTMLPurifier_HTMLDefinition->setup() processing.
  28      */
  29     public $attr = array();
  30
  31     /**
  32      * Indexed list of tag's HTMLPurifier_AttrTransform to be done before validation
  33      */
  34     public $attr_transform_pre = array();
  35
  36     /**
  37      * Indexed list of tag's HTMLPurifier_AttrTransform to be done after validation
  38      */
  39     public $attr_transform_post = array();
  40
  41     /**
  42      * HTMLPurifier_ChildDef of this tag.
  43      */
  44     public $child;
  45
  46     /**
  47      * Abstract string representation of internal ChildDef rules. See
  48      * HTMLPurifier_ContentSets for how this is parsed and then transformed
  49      * into an HTMLPurifier_ChildDef.
  50      * @warning This is a temporary variable that is not available after
  51      *      being processed by HTMLDefinition
  52      */
  53     public $content_model;
  54
  55     /**
  56      * Value of $child->type, used to determine which ChildDef to use,
  57      * used in combination with $content_model.
  58      * @warning This must be lowercase
  59      * @warning This is a temporary variable that is not available after
  60      *      being processed by HTMLDefinition
  61      */
  62     public $content_model_type;
  63
  64
  65
  66     /**
  67      * Does the element have a content model (#PCDATA | Inline)*? This
  68      * is important for chameleon ins and del processing in
  69      * HTMLPurifier_ChildDef_Chameleon. Dynamically set: modules don't
  70      * have to worry about this one.
  71      */
  72     public $descendants_are_inline = false;
  73
  74     /**
  75      * List of the names of required attributes this element has. Dynamically
  76      * populated by HTMLPurifier_HTMLDefinition::getElement
  77      */
  78     public $required_attr = array();
  79
  80     /**
  81      * Lookup table of tags excluded from all descendants of this tag.
  82      * @note SGML permits exclusions for all descendants, but this is
  83      *       not possible with DTDs or XML Schemas. W3C has elected to
  84      *       use complicated compositions of content_models to simulate
  85      *       exclusion for children, but we go the simpler, SGML-style
  86      *       route of flat-out exclusions, which correctly apply to
  87      *       all descendants and not just children. Note that the XHTML
  88      *       Modularization Abstract Modules are blithely unaware of such
  89      *       distinctions.
  90      */
  91     public $excludes = array();
  92
  93     /**
  94      * Low-level factory constructor for creating new standalone element defs
  95      */
  96     public static function create($content_model, $content_model_type, $attr) {
  97         $def = new HTMLPurifier_ElementDef();
  98         $def->content_model = $content_model;
  99         $def->content_model_type = $content_model_type;
 100         $def->attr = $attr;
 101         return $def;
 102     }
 103
 104     /**
 105      * Merges the values of another element definition into this one.
 106      * Values from the new element def take precedence if a value is
 107      * not mergeable.
 108      */
 109     public function mergeIn($def) {
 110
 111         // later keys takes precedence
 112         foreach($def->attr as $k => $v) {
 113             if ($k === 0) {
 114                 // merge in the includes
 115                 // sorry, no way to override an include
 116                 foreach ($v as $v2) {
 117                     $this->attr[0][] = $v2;
 118                 }
 119                 continue;
 120             }
 121             if ($v === false) {
 122                 if (isset($this->attr[$k])) unset($this->attr[$k]);
 123                 continue;
 124             }
 125             $this->attr[$k] = $v;
 126         }
 127         $this->_mergeAssocArray($this->attr_transform_pre, $def->attr_transform_pre);
 128         $this->_mergeAssocArray($this->attr_transform_post, $def->attr_transform_post);
 129         $this->_mergeAssocArray($this->excludes, $def->excludes);
 130
 131         if(!empty($def->content_model)) {
 132             $this->content_model .= ' | ' . $def->content_model;
 133             $this->child = false;
 134         }
 135         if(!empty($def->content_model_type)) {
 136             $this->content_model_type = $def->content_model_type;
 137             $this->child = false;
 138         }
 139         if(!is_null($def->child)) $this->child = $def->child;
 140         if($def->descendants_are_inline) $this->descendants_are_inline = $def->descendants_are_inline;
 141
 142     }
 143
 144     /**
 145      * Merges one array into another, removes values which equal false
 146      * @param $a1 Array by reference that is merged into
 147      * @param $a2 Array that merges into $a1
 148      */
 149     private function _mergeAssocArray(&$a1, $a2) {
 150         foreach ($a2 as $k => $v) {
 151             if ($v === false) {
 152                 if (isset($a1[$k])) unset($a1[$k]);
 153                 continue;
 154             }
 155             $a1[$k] = $v;
 156         }
 157     }
 158
 159 }
 160
 161 // vim: et sw=4 sts=4