library/HTMLPurifier/AttrCollections.php

   1 <?php
   2
   3 /**
   4  * Defines common attribute collections that modules reference
   5  */
   6
   7 class HTMLPurifier_AttrCollections
   8 {
   9
  10     /**
  11      * Associative array of attribute collections, indexed by name
  12      */
  13     public $info = array();
  14
  15     /**
  16      * Performs all expansions on internal data for use by other inclusions
  17      * It also collects all attribute collection extensions from
  18      * modules
  19      * @param $attr_types HTMLPurifier_AttrTypes instance
  20      * @param $modules Hash array of HTMLPurifier_HTMLModule members
  21      */
  22     public function __construct($attr_types, $modules) {
  23         // load extensions from the modules
  24         foreach ($modules as $module) {
  25             foreach ($module->attr_collections as $coll_i => $coll) {
  26                 if (!isset($this->info[$coll_i])) {
  27                     $this->info[$coll_i] = array();
  28                 }
  29                 foreach ($coll as $attr_i => $attr) {
  30                     if ($attr_i === 0 && isset($this->info[$coll_i][$attr_i])) {
  31                         // merge in includes
  32                         $this->info[$coll_i][$attr_i] = array_merge(
  33                             $this->info[$coll_i][$attr_i], $attr);
  34                         continue;
  35                     }
  36                     $this->info[$coll_i][$attr_i] = $attr;
  37                 }
  38             }
  39         }
  40         // perform internal expansions and inclusions
  41         foreach ($this->info as $name => $attr) {
  42             // merge attribute collections that include others
  43             $this->performInclusions($this->info[$name]);
  44             // replace string identifiers with actual attribute objects
  45             $this->expandIdentifiers($this->info[$name], $attr_types);
  46         }
  47     }
  48
  49     /**
  50      * Takes a reference to an attribute associative array and performs
  51      * all inclusions specified by the zero index.
  52      * @param &$attr Reference to attribute array
  53      */
  54     public function performInclusions(&$attr) {
  55         if (!isset($attr[0])) return;
  56         $merge = $attr[0];
  57         $seen  = array(); // recursion guard
  58         // loop through all the inclusions
  59         for ($i = 0; isset($merge[$i]); $i++) {
  60             if (isset($seen[$merge[$i]])) continue;
  61             $seen[$merge[$i]] = true;
  62             // foreach attribute of the inclusion, copy it over
  63             if (!isset($this->info[$merge[$i]])) continue;
  64             foreach ($this->info[$merge[$i]] as $key => $value) {
  65                 if (isset($attr[$key])) continue; // also catches more inclusions
  66                 $attr[$key] = $value;
  67             }
  68             if (isset($this->info[$merge[$i]][0])) {
  69                 // recursion
  70                 $merge = array_merge($merge, $this->info[$merge[$i]][0]);
  71             }
  72         }
  73         unset($attr[0]);
  74     }
  75
  76     /**
  77      * Expands all string identifiers in an attribute array by replacing
  78      * them with the appropriate values inside HTMLPurifier_AttrTypes
  79      * @param &$attr Reference to attribute array
  80      * @param $attr_types HTMLPurifier_AttrTypes instance
  81      */
  82     public function expandIdentifiers(&$attr, $attr_types) {
  83
  84         // because foreach will process new elements we add, make sure we
  85         // skip duplicates
  86         $processed = array();
  87
  88         foreach ($attr as $def_i => $def) {
  89             // skip inclusions
  90             if ($def_i === 0) continue;
  91
  92             if (isset($processed[$def_i])) continue;
  93
  94             // determine whether or not attribute is required
  95             if ($required = (strpos($def_i, '*') !== false)) {
  96                 // rename the definition
  97                 unset($attr[$def_i]);
  98                 $def_i = trim($def_i, '*');
  99                 $attr[$def_i] = $def;
 100             }
 101
 102             $processed[$def_i] = true;
 103
 104             // if we've already got a literal object, move on
 105             if (is_object($def)) {
 106                 // preserve previous required
 107                 $attr[$def_i]->required = ($required || $attr[$def_i]->required);
 108                 continue;
 109             }
 110
 111             if ($def === false) {
 112                 unset($attr[$def_i]);
 113                 continue;
 114             }
 115
 116             if ($t = $attr_types->get($def)) {
 117                 $attr[$def_i] = $t;
 118                 $attr[$def_i]->required = $required;
 119             } else {
 120                 unset($attr[$def_i]);
 121             }
 122         }
 123
 124     }
 125
 126 }
 127
 128 // vim: et sw=4 sts=4