Fix so microseconds macro (u) in log_date_format works (#1490446)

CHANGELOG

@@ -10,6 +10,7 @@ CHANGELOG Roundcube Webmail
 - Plugin API: Added message_ready hook
 - Plugin API: Add special onload() method to execute plugin actions before startup (session and GUI initialization)
 - Implemented UI element to jump to specified page of the messages list (#1485235)
+- Fix so microseconds macro (u) in log_date_format works (#1490446)
 - Fix so unrecognized TNEF attachments are displayed on the list of attachments (#1490351)
 - Fix "Importing..." message does not hide on error (#1490422)
 - Fix Compose action in addressbook for results from multiple addressbooks (#1490413)

program/lib/Roundcube/rcube.php

@@ -1231,11 +1231,7 @@ class rcube
             $session_key = intval(self::$instance->config->get('log_session_id', 8));
         }
 
-        if (empty($date_format)) {
-            $date_format = 'd-M-Y H:i:s O';
-        }
-
-        $date = date($date_format);
+        $date = rcube_utils::date_format($date_format);
 
         // trigger logging hook
         if (is_object(self::$instance) && is_object(self::$instance->plugins)) {

program/lib/Roundcube/rcube_utils.php

@@ -1149,4 +1149,27 @@ class rcube_utils
 
         return $random;
     }
+
+    /**
+     * Format current date according to specified format.
+     * This method supports microseconds (u).
+     *
+     * @param string $format Date format (default: 'd-M-Y H:i:s O')
+     *
+     * @return string Formatted date
+     */
+    public static function date_format($format = null)
+    {
+        if (empty($format)) {
+            $format = 'd-M-Y H:i:s O';
+        }
+
+        if (strpos($format, 'u') !== false
+            && ($date = date_create_from_format('U.u.e', microtime(true) . '.' . date_default_timezone_get()))
+        ) {
+            return $date->format($format);
+        }
+
+        return date($format);
+    }
 }