library/HTMLPurifier/URIParser.php

   1 <?php
   2
   3 /**
   4  * Parses a URI into the components and fragment identifier as specified
   5  * by RFC 3986.
   6  */
   7 class HTMLPurifier_URIParser
   8 {
   9
  10     /**
  11      * Instance of HTMLPurifier_PercentEncoder to do normalization with.
  12      */
  13     protected $percentEncoder;
  14
  15     public function __construct() {
  16         $this->percentEncoder = new HTMLPurifier_PercentEncoder();
  17     }
  18
  19     /**
  20      * Parses a URI.
  21      * @param $uri string URI to parse
  22      * @return HTMLPurifier_URI representation of URI. This representation has
  23      *         not been validated yet and may not conform to RFC.
  24      */
  25     public function parse($uri) {
  26
  27         $uri = $this->percentEncoder->normalize($uri);
  28
  29         // Regexp is as per Appendix B.
  30         // Note that ["<>] are an addition to the RFC's recommended
  31         // characters, because they represent external delimeters.
  32         $r_URI = '!'.
  33             '(([^:/?#"<>]+):)?'. // 2. Scheme
  34             '(//([^/?#"<>]*))?'. // 4. Authority
  35             '([^?#"<>]*)'.       // 5. Path
  36             '(\?([^#"<>]*))?'.   // 7. Query
  37             '(#([^"<>]*))?'.     // 8. Fragment
  38             '!';
  39
  40         $matches = array();
  41         $result = preg_match($r_URI, $uri, $matches);
  42
  43         if (!$result) return false; // *really* invalid URI
  44
  45         // seperate out parts
  46         $scheme     = !empty($matches[1]) ? $matches[2] : null;
  47         $authority  = !empty($matches[3]) ? $matches[4] : null;
  48         $path       = $matches[5]; // always present, can be empty
  49         $query      = !empty($matches[6]) ? $matches[7] : null;
  50         $fragment   = !empty($matches[8]) ? $matches[9] : null;
  51
  52         // further parse authority
  53         if ($authority !== null) {
  54             $r_authority = "/^((.+?)@)?(\[[^\]]+\]|[^:]*)(:(\d*))?/";
  55             $matches = array();
  56             preg_match($r_authority, $authority, $matches);
  57             $userinfo   = !empty($matches[1]) ? $matches[2] : null;
  58             $host       = !empty($matches[3]) ? $matches[3] : '';
  59             $port       = !empty($matches[4]) ? (int) $matches[5] : null;
  60         } else {
  61             $port = $host = $userinfo = null;
  62         }
  63
  64         return new HTMLPurifier_URI(
  65             $scheme, $userinfo, $host, $port, $path, $query, $fragment);
  66     }
  67
  68 }
  69
  70 // vim: et sw=4 sts=4