library/HTMLPurifier/VarParser.php

   1 <?php
   2
   3 /**
   4  * Parses string representations into their corresponding native PHP
   5  * variable type.
   6  */
   7 class HTMLPurifier_VarParser
   8 {
   9
  10     /**
  11      * Lookup table of allowed types.
  12      */
  13     public $types = array(
  14         'string'    => true,
  15         'istring'   => true,
  16         'text'      => true,
  17         'itext'     => true,
  18         'int'       => true,
  19         'float'     => true,
  20         'bool'      => true,
  21         'lookup'    => true,
  22         'list'      => true,
  23         'hash'      => true,
  24         'mixed'     => true
  25     );
  26
  27     /**
  28      * Validate a variable according to type. Throws exception if invalid.
  29      * It may return NULL as a valid type.
  30      */
  31     public function parse($var, $type, $allow_null = false) {
  32         if (!isset($this->types[$type])) {
  33             throw new HTMLPurifier_VarParserException("Invalid type $type");
  34         }
  35         if ($allow_null && $var === null) return null;
  36         switch ($type) {
  37             // Note: if code "breaks" from the switch, it triggers a generic
  38             // exception to be thrown. Specific errors can be specifically
  39             // done here.
  40             case 'mixed':
  41                 //if (is_string($var)) $var = unserialize($var);
  42                 return $var;
  43             case 'istring':
  44             case 'string':
  45             case 'text': // no difference, just is longer/multiple line string
  46             case 'itext':
  47                 if (!is_string($var)) break;
  48                 if ($type === 'istring' || $type === 'itext') $var = strtolower($var);
  49                 return $var;
  50             case 'int':
  51                 if (is_string($var) && ctype_digit($var)) $var = (int) $var;
  52                 elseif (!is_int($var)) break;
  53                 return $var;
  54             case 'float':
  55                 if (is_string($var) && is_numeric($var)) $var = (float) $var;
  56                 elseif (!is_float($var)) break;
  57                 return $var;
  58             case 'bool':
  59                 if (is_int($var) && ($var === 0 || $var === 1)) {
  60                     $var = (bool) $var;
  61                 } elseif (is_string($var)) {
  62                     if ($var == 'on' || $var == 'true' || $var == '1') {
  63                         $var = true;
  64                     } elseif ($var == 'off' || $var == 'false' || $var == '0') {
  65                         $var = false;
  66                     } else {
  67                         throw new HTMLPurifier_VarParserException("Unrecognized value '$var' for $type");
  68                     }
  69                 } elseif (!is_bool($var)) break;
  70                 return $var;
  71             case 'list':
  72             case 'hash':
  73             case 'lookup':
  74                 if (is_string($var)) {
  75                     // special case: technically, this is an array with
  76                     // a single empty string item, but having an empty
  77                     // array is more intuitive
  78                     if ($var == '') return array();
  79                     if (strpos($var, "\n") === false && strpos($var, "\r") === false) {
  80                         // simplistic string to array method that only works
  81                         // for simple lists of tag names or alphanumeric characters
  82                         $var = explode(',',$var);
  83                     } else {
  84                         $var = preg_split('/(,|[\n\r]+)/', $var);
  85                     }
  86                     // remove spaces
  87                     foreach ($var as $i => $j) $var[$i] = trim($j);
  88                     if ($type === 'hash') {
  89                         // key:value,key2:value2
  90                         $nvar = array();
  91                         foreach ($var as $keypair) {
  92                             $c = explode(':', $keypair, 2);
  93                             if (!isset($c[1])) continue;
  94                             $nvar[$c[0]] = $c[1];
  95                         }
  96                         $var = $nvar;
  97                     }
  98                 }
  99                 if (!is_array($var)) break;
 100                 $keys = array_keys($var);
 101                 if ($keys === array_keys($keys)) {
 102                     if ($type == 'list') return $var;
 103                     elseif ($type == 'lookup') {
 104                         $new = array();
 105                         foreach ($var as $key) {
 106                             $new[$key] = true;
 107                         }
 108                         return $new;
 109                     } else break;
 110                 }
 111                 if ($type === 'lookup') {
 112                     foreach ($var as $key => $value) {
 113                         $var[$key] = true;
 114                     }
 115                 }
 116                 return $var;
 117             default:
 118                 // This should not happen!
 119                 throw new HTMLPurifier_Exception("Inconsistency in HTMLPurifier_VarParser: $type is not implemented");
 120         }
 121         throw new HTMLPurifier_VarParserException("Invalid input for type $type");
 122     }
 123
 124 }