MDL-9151 HTML Purifier cleaning support - enable switch is in experimental section

MDL-9435 Reviewved url cleaning in redirect()

lib/htmlpurifier/HTMLPurifier/ContentSets.php

@@ -0,0 +1,148 @@
+<?php
+
+// common defs that we'll support by default
+require_once 'HTMLPurifier/ChildDef.php';
+require_once 'HTMLPurifier/ChildDef/Empty.php';
+require_once 'HTMLPurifier/ChildDef/Required.php';
+require_once 'HTMLPurifier/ChildDef/Optional.php';
+
+class HTMLPurifier_ContentSets
+{
+    
+    /**
+     * List of content set strings (pipe seperators) indexed by name.
+     * @public
+     */
+    var $info = array();
+    
+    /**
+     * List of content set lookups (element => true) indexed by name.
+     * @note This is in HTMLPurifier_HTMLDefinition->info_content_sets
+     * @public
+     */
+    var $lookup = array();
+    
+    /**
+     * Synchronized list of defined content sets (keys of info)
+     */
+    var $keys = array();
+    /**
+     * Synchronized list of defined content values (values of info)
+     */
+    var $values = array();
+    
+    /**
+     * Merges in module's content sets, expands identifiers in the content
+     * sets and populates the keys, values and lookup member variables.
+     * @param $modules List of HTMLPurifier_HTMLModule
+     */
+    function HTMLPurifier_ContentSets($modules) {
+        if (!is_array($modules)) $modules = array($modules);
+        // populate content_sets based on module hints
+        // sorry, no way of overloading
+        foreach ($modules as $module_i => $module) {
+            foreach ($module->content_sets as $key => $value) {
+                if (isset($this->info[$key])) {
+                    // add it into the existing content set
+                    $this->info[$key] = $this->info[$key] . ' | ' . $value;
+                } else {
+                    $this->info[$key] = $value;
+                }
+            }
+        }
+        // perform content_set expansions
+        $this->keys = array_keys($this->info);
+        foreach ($this->info as $i => $set) {
+            // only performed once, so infinite recursion is not
+            // a problem
+            $this->info[$i] =
+                str_replace(
+                    $this->keys,
+                    // must be recalculated each time due to
+                    // changing substitutions
+                    array_values($this->info),
+                $set);
+        }
+        $this->values = array_values($this->info);
+        
+        // generate lookup tables
+        foreach ($this->info as $name => $set) {
+            $this->lookup[$name] = $this->convertToLookup($set);
+        }
+    }
+    
+    /**
+     * Accepts a definition; generates and assigns a ChildDef for it
+     * @param $def HTMLPurifier_ElementDef reference
+     * @param $module Module that defined the ElementDef
+     */
+    function generateChildDef(&$def, $module) {
+        if (!empty($def->child)) return; // already done!
+        $content_model = $def->content_model;
+        if (is_string($content_model)) {
+            $def->content_model = str_replace(
+                $this->keys, $this->values, $content_model);
+        }
+        $def->child = $this->getChildDef($def, $module);
+    }
+    
+    /**
+     * Instantiates a ChildDef based on content_model and content_model_type
+     * member variables in HTMLPurifier_ElementDef
+     * @note This will also defer to modules for custom HTMLPurifier_ChildDef
+     *       subclasses that need content set expansion
+     * @param $def HTMLPurifier_ElementDef to have ChildDef extracted
+     * @return HTMLPurifier_ChildDef corresponding to ElementDef
+     */
+    function getChildDef($def, $module) {
+        $value = $def->content_model;
+        if (is_object($value)) {
+            trigger_error(
+                'Literal object child definitions should be stored in '.
+                'ElementDef->child not ElementDef->content_model',
+                E_USER_NOTICE
+            );
+            return $value;
+        }
+        switch ($def->content_model_type) {
+            case 'required':
+                return new HTMLPurifier_ChildDef_Required($value);
+            case 'optional':
+                return new HTMLPurifier_ChildDef_Optional($value);
+            case 'empty':
+                return new HTMLPurifier_ChildDef_Empty();
+            case 'custom':
+                return new HTMLPurifier_ChildDef_Custom($value);
+        }
+        // defer to its module
+        $return = false;
+        if ($module->defines_child_def) { // save a func call
+            $return = $module->getChildDef($def);
+        }
+        if ($return !== false) return $return;
+        // error-out
+        trigger_error(
+            'Could not determine which ChildDef class to instantiate',
+            E_USER_ERROR
+        );
+        return false;
+    }
+    
+    /**
+     * Converts a string list of elements separated by pipes into
+     * a lookup array.
+     * @param $string List of elements
+     * @return Lookup array of elements
+     */
+    function convertToLookup($string) {
+        $array = explode('|', str_replace(' ', '', $string));
+        $ret = array();
+        foreach ($array as $i => $k) {
+            $ret[$k] = true;
+        }
+        return $ret;
+    }
+    
+}
+
+?>