Allow empty strings for imap_root config parameter (was changed in r2143) to remain backward compatible but cache imap root and delimiter in session

UPGRADING

@@ -18,8 +18,6 @@ of RoundCube Webmail.
    open http://url-to-roundcube/installer/ in a browser. To enable
    the latter one, you have to temporary set 'enable_installer' to true
    in your local config/main.inc.php file.
-   WARNING: If you don't know what an "IMAP root directory" is,
-   set the imap_root option to NULL
 3. Let the update script/installer check your configuration and
    update your config files as suggested by the updater.
 4. If suggested by the update script, run all commands in

config/main.inc.php.dist

@@ -62,8 +62,7 @@ $rcmail_config['default_port'] = 143;
 $rcmail_config['imap_auth_type'] = null;
 
 // If you know your imap's root directory and its folder delimiter,
-// you can specify them here. Otherwise they will be determined
-// during every imap connection.
+// you can specify them here. Otherwise they will be determined automatically.
 $rcmail_config['imap_root'] = null;
 $rcmail_config['imap_delimiter'] = null;
 

program/include/rcmail.php

@@ -352,6 +352,20 @@ class rcmail
 
     // set pagesize from config
     $this->imap->set_pagesize($this->config->get('pagesize', 50));
+    
+    // Setting root and delimiter before iil_Connect can save time detecting them
+    // using NAMESPACE and LIST 
+    $options = array(
+      'imap' => $this->config->get('imap_auth_type', 'check'),
+      'delimiter' => isset($_SESSION['imap_delimiter']) ? $_SESSION['imap_delimiter'] : $this->config->get('imap_delimiter'),
+    );
+    
+    if (isset($_SESSION['imap_root']))
+      $options['rootdir'] = $_SESSION['imap_root'];
+    else if ($imap_root = $this->config->get('imap_root'))
+      $options['rootdir'] = $imap_root;
+    
+    $this->imap->set_options($options);
   
     // set global object for backward compatibility
     $GLOBALS['IMAP'] = $this->imap;
@@ -371,7 +385,7 @@ class rcmail
     $conn = false;
     
     if ($_SESSION['imap_host'] && !$this->imap->conn) {
-      if (!($conn = $this->imap->connect($_SESSION['imap_host'], $_SESSION['username'], $this->decrypt_passwd($_SESSION['password']), $_SESSION['imap_port'], $_SESSION['imap_ssl'], rcmail::get_instance()->config->get('imap_auth_type', 'check')))) {
+      if (!($conn = $this->imap->connect($_SESSION['imap_host'], $_SESSION['username'], $this->decrypt_passwd($_SESSION['password']), $_SESSION['imap_port'], $_SESSION['imap_ssl']))) {
         if ($this->output)
           $this->output->show_message($this->imap->error_code == -1 ? 'imaperror' : 'sessionerror', 'error');
       }
@@ -452,7 +466,7 @@ class rcmail
       $username = $user->data['username'];
 
     // exit if IMAP login failed
-    if (!($imap_login  = $this->imap->connect($host, $username, $pass, $imap_port, $imap_ssl, $config['imap_auth_type'])))
+    if (!($imap_login  = $this->imap->connect($host, $username, $pass, $imap_port, $imap_ssl)))
       return false;
 
     // user already registered -> update user's record
@@ -524,6 +538,10 @@ class rcmail
     if (isset($_SESSION['page'])) {
       $this->imap->set_page($_SESSION['page']);
     }
+    
+    // cache IMAP root and delimiter in session for performance reasons
+    $_SESSION['imap_root'] = $this->imap->root_dir;
+    $_SESSION['imap_delimiter'] = $this->imap->delimiter;
   }
 
 

program/include/rcube_imap.php

@@ -66,6 +66,7 @@ class rcube_imap
   var $search_sort_field = '';  
   var $debug_level = 1;
   var $error_code = 0;
+  var $options = array('imap' => 'check');
 
 
   /**
@@ -90,7 +91,7 @@ class rcube_imap
    * @return boolean  TRUE on success, FALSE on failure
    * @access public
    */
-  function connect($host, $user, $pass, $port=143, $use_ssl=null, $auth_type=null)
+  function connect($host, $user, $pass, $port=143, $use_ssl=null)
     {
     global $ICL_SSL, $ICL_PORT, $IMAP_USE_INTERNAL_DATE;
     
@@ -107,17 +108,7 @@ class rcube_imap
     $ICL_PORT = $port;
     $IMAP_USE_INTERNAL_DATE = false;
 
-    // set connection options
-    $options['imap'] = $auth_type ? $auth_type : 'check';
-
-    // Setting root and delimiter before iil_Connect can save time detecting them
-    // using NAMESPACE and LIST 
-    if (is_string($imap_root = rcmail::get_instance()->config->get('imap_root'))) 
-        $options['rootdir'] = $imap_root;
-    if($imap_delimiter = rcmail::get_instance()->config->get('imap_delimiter'))
-        $options['delimiter'] = $imap_delimiter;
-
-    $this->conn = iil_Connect($host, $user, $pass, $options);
+    $this->conn = iil_Connect($host, $user, $pass, $this->options);
     $this->host = $host;
     $this->user = $user;
     $this->pass = $pass;
@@ -182,6 +173,13 @@ class rcube_imap
       iil_C_Select($this->conn, $this->mailbox);
     }
 
+  /**
+   * Set options to be used in iil_Connect()
+   */
+  function set_options($opt)
+  {
+    $this->options = array_merge((array)$opt, $this->options);
+  }
 
   /**
    * Set a root folder for the IMAP connection.
@@ -198,6 +196,7 @@ class rcube_imap
       $root = substr($root, 0, -1);
 
     $this->root_dir = $root;
+    $this->options['rootdir'] = $root;
     
     if (empty($this->delimiter))
       $this->get_hierarchy_delimiter();