library/HTMLPurifier/AttrDef/HTML/Color.php

   1 <?php
   2
   3 /**
   4  * Validates a color according to the HTML spec.
   5  */
   6 class HTMLPurifier_AttrDef_HTML_Color extends HTMLPurifier_AttrDef
   7 {
   8
   9     /**
  10      * @param string $string
  11      * @param HTMLPurifier_Config $config
  12      * @param HTMLPurifier_Context $context
  13      * @return bool|string
  14      */
  15     public function validate($string, $config, $context)
  16     {
  17         static $colors = null;
  18         if ($colors === null) {
  19             $colors = $config->get('Core.ColorKeywords');
  20         }
  21
  22         $string = trim($string);
  23
  24         if (empty($string)) {
  25             return false;
  26         }
  27         $lower = strtolower($string);
  28         if (isset($colors[$lower])) {
  29             return $colors[$lower];
  30         }
  31         if ($string[0] === '#') {
  32             $hex = substr($string, 1);
  33         } else {
  34             $hex = $string;
  35         }
  36
  37         $length = strlen($hex);
  38         if ($length !== 3 && $length !== 6) {
  39             return false;
  40         }
  41         if (!ctype_xdigit($hex)) {
  42             return false;
  43         }
  44         if ($length === 3) {
  45             $hex = $hex[0] . $hex[0] . $hex[1] . $hex[1] . $hex[2] . $hex[2];
  46         }
  47         return "#$hex";
  48     }
  49 }
  50
  51 // vim: et sw=4 sts=4