lib/htmlpurifier/HTMLPurifier/AttrDef.php

   1 <?php
   2
   3 /**
   4  * Base class for all validating attribute definitions.
   5  *
   6  * This family of classes forms the core for not only HTML attribute validation,
   7  * but also any sort of string that needs to be validated or cleaned (which
   8  * means CSS properties and composite definitions are defined here too).
   9  * Besides defining (through code) what precisely makes the string valid,
  10  * subclasses are also responsible for cleaning the code if possible.
  11  */
  12
  13 class HTMLPurifier_AttrDef
  14 {
  15
  16     /**
  17      * Tells us whether or not an HTML attribute is minimized. Only the
  18      * boolean attribute vapourware would use this.
  19      */
  20     var $minimized = false;
  21
  22     /**
  23      * Validates and cleans passed string according to a definition.
  24      *
  25      * @public
  26      * @param $string String to be validated and cleaned.
  27      * @param $config Mandatory HTMLPurifier_Config object.
  28      * @param $context Mandatory HTMLPurifier_AttrContext object.
  29      */
  30     function validate($string, $config, &$context) {
  31         trigger_error('Cannot call abstract function', E_USER_ERROR);
  32     }
  33
  34     /**
  35      * Convenience method that parses a string as if it were CDATA.
  36      *
  37      * This method process a string in the manner specified at
  38      * <http://www.w3.org/TR/html4/types.html#h-6.2> by removing
  39      * leading and trailing whitespace, ignoring line feeds, and replacing
  40      * carriage returns and tabs with spaces.  While most useful for HTML
  41      * attributes specified as CDATA, it can also be applied to most CSS
  42      * values.
  43      *
  44      * @note This method is not entirely standards compliant, as trim() removes
  45      *       more types of whitespace than specified in the spec. In practice,
  46      *       this is rarely a problem, as those extra characters usually have
  47      *       already been removed by HTMLPurifier_Encoder.
  48      *
  49      * @warning This processing is inconsistent with XML's whitespace handling
  50      *          as specified by section 3.3.3 and referenced XHTML 1.0 section
  51      *          4.7.  Compliant processing requires all line breaks normalized
  52      *          to "\n", so the fix is not as simple as fixing it in this
  53      *          function.  Trim and whitespace collapsing are supposed to only
  54      *          occur in NMTOKENs.  However, note that we are NOT necessarily
  55      *          parsing XML, thus, this behavior may still be correct.
  56      *
  57      * @public
  58      */
  59     function parseCDATA($string) {
  60         $string = trim($string);
  61         $string = str_replace("\n", '', $string);
  62         $string = str_replace(array("\r", "\t"), ' ', $string);
  63         return $string;
  64     }
  65 }
  66
  67 ?>