2 files changed, 44 insertions, 1 deletions
diff --git a/lib/plugins/config/settings/config.class.php b/lib/plugins/config/settings/config.class.php
index ec5f73fa5..bbb25b695 100644
--- a/lib/plugins/config/settings/config.class.php
+++ b/lib/plugins/config/settings/config.class.php
@@ -1081,3 +1081,40 @@ if (!class_exists('setting_multicheckbox')) {
     }
   }
 }
+
+if (!class_exists('setting_regex')){
+   class setting_regex extends setting_string {
+
+        var $_delimiter = '/';    // regex delimiter to be used in testing input
+        var $_pregflags = 'ui';   // regex pattern modifiers to be used in testing input
+
+        /**
+         *  update changed setting with user provided value $input
+         *  - if changed value fails error check, save it to $this->_input (to allow echoing later)
+         *  - if changed value passes error check, set $this->_local to the new value
+         *
+         *  @param  mixed   $input   the new value
+         *  @return boolean          true if changed, false otherwise (incl. on error)
+         */
+        function update($input) {
+
+            // let parent do basic checks, value, not changed, etc.
+            $local = $this->_local;
+            if (!parent::update($input)) return false;
+            $this->_local = $local;
+
+            // see if the regex compiles and runs (we don't check for effectiveness)
+            $regex = $this->_delimiter . $input . $this->_delimiter . $this->_pregflags;
+            $lastError = error_get_last();
+            $ok = @preg_match($regex,'testdata');
+            if (preg_last_error() != PREG_NO_ERROR || error_get_last() != $lastError) {
+                $this->_input = $input;
+                $this->_error = true;
+                return false;
+            }
+
+            $this->_local = $input;
+            return true;
+        }
+    }
+}
+\ No newline at end of file
diff --git a/lib/plugins/config/settings/config.metadata.php b/lib/plugins/config/settings/config.metadata.php
index 4731ffc16..5aedaa6f1 100644
--- a/lib/plugins/config/settings/config.metadata.php
+++ b/lib/plugins/config/settings/config.metadata.php
@@ -33,6 +33,9 @@
  *   'array'        - a simple (one dimensional) array of string values, shown as comma separated list in the
  *                    config manager but saved as PHP array(). Values may not contain commas themselves.
  *                    _pattern matching on the array values supported.
+ *   'regex'        - regular expression string, normally without delimiters; as for string, in addition tested
+ *                    to see if will compile & run as a regex.  in addition to _pattern, also accepts _delimiter
+ *                    (default '/') and _pregflags (default 'ui')
  *
  *  Single Setting (source: settings/extra.class.php)
  *  -------------------------------------------------
@@ -60,6 +63,9 @@
  *   '_code'       - encoding method to use, accepted values: 'base64','uuencode','plain'.  defaults to plain.
  *   '_min'        - minimum numeric value, optional for 'numeric' and 'numericopt', ignored by others
  *   '_max'        - maximum numeric value, optional for 'numeric' and 'numericopt', ignored by others
+ *   '_delimiter'  - string, default '/', a single character used as a delimiter for testing regex input values
+ *   '_pregflags'  - string, default 'ui', valid preg pattern modifiers used when testing regex input values, for more
+ *                   information see http://uk1.php.net/manual/en/reference.pcre.pattern.modifiers.php
  *
  * @author    Chris Smith <chris@jalakai.co.uk>
  */
@@ -115,7 +121,7 @@ $meta['camelcase']   = array('onoff');
 $meta['deaccent']    = array('multichoice','_choices' => array(0,1,2));
 $meta['useheading']  = array('multichoice','_choices' => array(0,'navigation','content',1));
 $meta['sneaky_index'] = array('onoff');
-$meta['hidepages']   = array('string');
+$meta['hidepages']   = array('regex');
 
 $meta['_authentication'] = array('fieldset');
 $meta['useacl']      = array('onoff');