library/HTMLPurifier/Context.php

   1 <?php
   2
   3 /**
   4  * Registry object that contains information about the current context.
   5  * @warning Is a bit buggy when variables are set to null: it thinks
   6  *          they don't exist! So use false instead, please.
   7  * @note Since the variables Context deals with may not be objects,
   8  *       references are very important here! Do not remove!
   9  */
  10 class HTMLPurifier_Context
  11 {
  12
  13     /**
  14      * Private array that stores the references.
  15      * @type array
  16      */
  17     private $_storage = array();
  18
  19     /**
  20      * Registers a variable into the context.
  21      * @param string $name String name
  22      * @param mixed $ref Reference to variable to be registered
  23      */
  24     public function register($name, &$ref)
  25     {
  26         if (array_key_exists($name, $this->_storage)) {
  27             trigger_error(
  28                 "Name $name produces collision, cannot re-register",
  29                 E_USER_ERROR
  30             );
  31             return;
  32         }
  33         $this->_storage[$name] =& $ref;
  34     }
  35
  36     /**
  37      * Retrieves a variable reference from the context.
  38      * @param string $name String name
  39      * @param bool $ignore_error Boolean whether or not to ignore error
  40      * @return mixed
  41      */
  42     public function &get($name, $ignore_error = false)
  43     {
  44         if (!array_key_exists($name, $this->_storage)) {
  45             if (!$ignore_error) {
  46                 trigger_error(
  47                     "Attempted to retrieve non-existent variable $name",
  48                     E_USER_ERROR
  49                 );
  50             }
  51             $var = null; // so we can return by reference
  52             return $var;
  53         }
  54         return $this->_storage[$name];
  55     }
  56
  57     /**
  58      * Destroys a variable in the context.
  59      * @param string $name String name
  60      */
  61     public function destroy($name)
  62     {
  63         if (!array_key_exists($name, $this->_storage)) {
  64             trigger_error(
  65                 "Attempted to destroy non-existent variable $name",
  66                 E_USER_ERROR
  67             );
  68             return;
  69         }
  70         unset($this->_storage[$name]);
  71     }
  72
  73     /**
  74      * Checks whether or not the variable exists.
  75      * @param string $name String name
  76      * @return bool
  77      */
  78     public function exists($name)
  79     {
  80         return array_key_exists($name, $this->_storage);
  81     }
  82
  83     /**
  84      * Loads a series of variables from an associative array
  85      * @param array $context_array Assoc array of variables to load
  86      */
  87     public function loadArray($context_array)
  88     {
  89         foreach ($context_array as $key => $discard) {
  90             $this->register($key, $context_array[$key]);
  91         }
  92     }
  93 }
  94
  95 // vim: et sw=4 sts=4