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Differences Between: [Versions 310 and 403] [Versions 311 and 403] [Versions 39 and 403] [Versions 400 and 403]

   1  <?php
   2  
   3  /**
   4   * Represents a measurable length, with a string numeric magnitude
   5   * and a unit. This object is immutable.
   6   */
   7  class HTMLPurifier_Length
   8  {
   9  
  10      /**
  11       * String numeric magnitude.
  12       * @type string
  13       */
  14      protected $n;
  15  
  16      /**
  17       * String unit. False is permitted if $n = 0.
  18       * @type string|bool
  19       */
  20      protected $unit;
  21  
  22      /**
  23       * Whether or not this length is valid. Null if not calculated yet.
  24       * @type bool
  25       */
  26      protected $isValid;
  27  
  28      /**
  29       * Array Lookup array of units recognized by CSS 3
  30       * @type array
  31       */
  32      protected static $allowedUnits = array(
  33          'em' => true, 'ex' => true, 'px' => true, 'in' => true,
  34          'cm' => true, 'mm' => true, 'pt' => true, 'pc' => true,
  35          'ch' => true, 'rem' => true, 'vw' => true, 'vh' => true,
  36          'vmin' => true, 'vmax' => true
  37      );
  38  
  39      /**
  40       * @param string $n Magnitude
  41       * @param bool|string $u Unit
  42       */
  43      public function __construct($n = '0', $u = false)
  44      {
  45          $this->n = (string) $n;
  46          $this->unit = $u !== false ? (string) $u : false;
  47      }
  48  
  49      /**
  50       * @param string $s Unit string, like '2em' or '3.4in'
  51       * @return HTMLPurifier_Length
  52       * @warning Does not perform validation.
  53       */
  54      public static function make($s)
  55      {
  56          if ($s instanceof HTMLPurifier_Length) {
  57              return $s;
  58          }
  59          $n_length = strspn($s, '1234567890.+-');
  60          $n = substr($s, 0, $n_length);
  61          $unit = substr($s, $n_length);
  62          if ($unit === '') {
  63              $unit = false;
  64          }
  65          return new HTMLPurifier_Length($n, $unit);
  66      }
  67  
  68      /**
  69       * Validates the number and unit.
  70       * @return bool
  71       */
  72      protected function validate()
  73      {
  74          // Special case:
  75          if ($this->n === '+0' || $this->n === '-0') {
  76              $this->n = '0';
  77          }
  78          if ($this->n === '0' && $this->unit === false) {
  79              return true;
  80          }
  81          if ($this->unit === false || !ctype_lower($this->unit)) {
  82              $this->unit = strtolower($this->unit);
  83          }
  84          if (!isset(HTMLPurifier_Length::$allowedUnits[$this->unit])) {
  85              return false;
  86          }
  87          // Hack:
  88          $def = new HTMLPurifier_AttrDef_CSS_Number();
  89          $result = $def->validate($this->n, false, false);
  90          if ($result === false) {
  91              return false;
  92          }
  93          $this->n = $result;
  94          return true;
  95      }
  96  
  97      /**
  98       * Returns string representation of number.
  99       * @return string
 100       */
 101      public function toString()
 102      {
 103          if (!$this->isValid()) {
 104              return false;
 105          }
 106          return $this->n . $this->unit;
 107      }
 108  
 109      /**
 110       * Retrieves string numeric magnitude.
 111       * @return string
 112       */
 113      public function getN()
 114      {
 115          return $this->n;
 116      }
 117  
 118      /**
 119       * Retrieves string unit.
 120       * @return string
 121       */
 122      public function getUnit()
 123      {
 124          return $this->unit;
 125      }
 126  
 127      /**
 128       * Returns true if this length unit is valid.
 129       * @return bool
 130       */
 131      public function isValid()
 132      {
 133          if ($this->isValid === null) {
 134              $this->isValid = $this->validate();
 135          }
 136          return $this->isValid;
 137      }
 138  
 139      /**
 140       * Compares two lengths, and returns 1 if greater, -1 if less and 0 if equal.
 141       * @param HTMLPurifier_Length $l
 142       * @return int
 143       * @warning If both values are too large or small, this calculation will
 144       *          not work properly
 145       */
 146      public function compareTo($l)
 147      {
 148          if ($l === false) {
 149              return false;
 150          }
 151          if ($l->unit !== $this->unit) {
 152              $converter = new HTMLPurifier_UnitConverter();
 153              $l = $converter->convert($l, $this->unit);
 154              if ($l === false) {
 155                  return false;
 156              }
 157          }
 158          return $this->n - $l->n;
 159      }
 160  }
 161  
 162  // vim: et sw=4 sts=4