XH_JSON::encode() errors on ASCII control characters

[cmb]

Hello Community,

thanks to marcus a bug has been found in XH_JSON::encode(), where ASCII control characters have been escaped to \u00, which is obviously invalid. In the case of Pagemanager the language strings are converted to JSON, what results in a script error when the fallback to XH_JSON::encode() is required (usually for PHP < 5.2), so the tree view won't get populated. This bug had already been reported by Archie900 a while ago, but due to lack of feedback it has not been resolved.

I suggest the following patch:

Code: Select all

Index: JSON.php
===================================================================
--- JSON.php	(revision 3)
+++ JSON.php	(working copy)
@@ -197,11 +197,27 @@
     function quote($string)
     {
         $string = addcslashes($string, "\"\\/");
-        $string = preg_replace('/[\x00-\x1f]/s', '\u00$1', $string);
+        $string = preg_replace_callback(
+            '/[\x00-\x1f]/', array($this, 'escapeControlChar'), $string
+        );
         return $string;
     }
 
     /**
+     * Escapes an ASCII control character for use in a JSON string.
+     *
+     * @param string $matches An array of matches with a single element.
+     *
+     * @return string
+     *
+     * @access protected
+     */
+    function escapeControlChar($matches)
+    {
+        return sprintf('\\u%04X', ord($matches[0]));
+    }
+
+    /**
      * Returns UTF-8 chars for JSON unicode escape sequence.
      *
      * @param array $matches Matches from the previous preg_match().

A respective unit test should be added as well.

Christoph

PS: See http://cmsimpleforum.com/viewtopic.php?f=10&t=8257 regarding a follow-up bug and the fix.

[cmb]

Done (r1423).