library/HTMLPurifier/AttrDef/CSS/Number.php

   1 <?php
   2
   3 /**
   4  * Validates a number as defined by the CSS spec.
   5  */
   6 class HTMLPurifier_AttrDef_CSS_Number extends HTMLPurifier_AttrDef
   7 {
   8
   9     /**
  10      * Indicates whether or not only positive values are allowed.
  11      * @type bool
  12      */
  13     protected $non_negative = false;
  14
  15     /**
  16      * @param bool $non_negative indicates whether negatives are forbidden
  17      */
  18     public function __construct($non_negative = false)
  19     {
  20         $this->non_negative = $non_negative;
  21     }
  22
  23     /**
  24      * @param string $number
  25      * @param HTMLPurifier_Config $config
  26      * @param HTMLPurifier_Context $context
  27      * @return string|bool
  28      * @warning Some contexts do not pass $config, $context. These
  29      *          variables should not be used without checking HTMLPurifier_Length
  30      */
  31     public function validate($number, $config, $context)
  32     {
  33         $number = $this->parseCDATA($number);
  34
  35         if ($number === '') {
  36             return false;
  37         }
  38         if ($number === '0') {
  39             return '0';
  40         }
  41
  42         $sign = '';
  43         switch ($number[0]) {
  44             case '-':
  45                 if ($this->non_negative) {
  46                     return false;
  47                 }
  48                 $sign = '-';
  49             case '+':
  50                 $number = substr($number, 1);
  51         }
  52
  53         if (ctype_digit($number)) {
  54             $number = ltrim($number, '0');
  55             return $number ? $sign . $number : '0';
  56         }
  57
  58         // Period is the only non-numeric character allowed
  59         if (strpos($number, '.') === false) {
  60             return false;
  61         }
  62
  63         list($left, $right) = explode('.', $number, 2);
  64
  65         if ($left === '' && $right === '') {
  66             return false;
  67         }
  68         if ($left !== '' && !ctype_digit($left)) {
  69             return false;
  70         }
  71
  72         $left = ltrim($left, '0');
  73         $right = rtrim($right, '0');
  74
  75         if ($right === '') {
  76             return $left ? $sign . $left : '0';
  77         } elseif (!ctype_digit($right)) {
  78             return false;
  79         }
  80         return $sign . $left . '.' . $right;
  81     }
  82 }
  83
  84 // vim: et sw=4 sts=4