--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/program/lib/Roundcube/rcube_imap_search.php	Thu Jan 04 15:52:31 2018 -0500
@@ -0,0 +1,229 @@
+<?php
+
+/**
+ +-----------------------------------------------------------------------+
+ | This file is part of the Roundcube Webmail client                     |
+ |                                                                       |
+ | Copyright (C) 2013, The Roundcube Dev Team                            |
+ | Copyright (C) 2014, Kolab Systems AG                                  |
+ |                                                                       |
+ | Licensed under the GNU General Public License version 3 or            |
+ | any later version with exceptions for skins & plugins.                |
+ | See the README file for a full license statement.                     |
+ |                                                                       |
+ | PURPOSE:                                                              |
+ |   Execute (multi-threaded) searches in multiple IMAP folders          |
+ +-----------------------------------------------------------------------+
+ | Author: Thomas Bruederli <roundcube@gmail.com>                        |
+ +-----------------------------------------------------------------------+
+*/
+
+/**
+ * Class to control search jobs on multiple IMAP folders.
+ *
+ * @package    Framework
+ * @subpackage Storage
+ * @author     Thomas Bruederli <roundcube@gmail.com>
+ */
+class rcube_imap_search
+{
+    public $options = array();
+
+    protected $jobs      = array();
+    protected $timelimit = 0;
+    protected $results;
+    protected $conn;
+
+    /**
+     * Default constructor
+     */
+    public function __construct($options, $conn)
+    {
+        $this->options = $options;
+        $this->conn    = $conn;
+    }
+
+    /**
+     * Invoke search request to IMAP server
+     *
+     * @param  array   $folders    List of IMAP folders to search in
+     * @param  string  $str        Search criteria
+     * @param  string  $charset    Search charset
+     * @param  string  $sort_field Header field to sort by
+     * @param  boolean $threading  True if threaded listing is active
+     */
+    public function exec($folders, $str, $charset = null, $sort_field = null, $threading=null)
+    {
+        $start   = floor(microtime(true));
+        $results = new rcube_result_multifolder($folders);
+
+        // start a search job for every folder to search in
+        foreach ($folders as $folder) {
+            // a complete result for this folder already exists
+            $result = $this->results ? $this->results->get_set($folder) : false;
+            if ($result && !$result->incomplete) {
+                $results->add($result);
+            }
+            else {
+                $search = is_array($str) && $str[$folder] ? $str[$folder] : $str;
+                $job = new rcube_imap_search_job($folder, $search, $charset, $sort_field, $threading);
+                $job->worker = $this;
+                $this->jobs[] = $job;
+            }
+        }
+
+        // execute jobs and gather results
+        foreach ($this->jobs as $job) {
+            // only run search if within the configured time limit
+            // TODO: try to estimate the required time based on folder size and previous search performance
+            if (!$this->timelimit || floor(microtime(true)) - $start < $this->timelimit) {
+                $job->run();
+            }
+
+            // add result (may have ->incomplete flag set)
+            $results->add($job->get_result());
+        }
+
+        return $results;
+    }
+
+    /**
+     * Setter for timelimt property
+     */
+    public function set_timelimit($seconds)
+    {
+        $this->timelimit = $seconds;
+    }
+
+    /**
+     * Setter for previous (potentially incomplete) search results
+     */
+    public function set_results($res)
+    {
+        $this->results = $res;
+    }
+
+    /**
+     * Get connection to the IMAP server
+     * (used for single-thread mode)
+     */
+    public function get_imap()
+    {
+        return $this->conn;
+    }
+}
+
+
+/**
+ * Stackable item to run the search on a specific IMAP folder
+ */
+class rcube_imap_search_job /* extends Stackable */
+{
+    private $folder;
+    private $search;
+    private $charset;
+    private $sort_field;
+    private $threading;
+    private $result;
+
+    public function __construct($folder, $str, $charset = null, $sort_field = null, $threading=false)
+    {
+        $this->folder     = $folder;
+        $this->search     = $str;
+        $this->charset    = $charset;
+        $this->sort_field = $sort_field;
+        $this->threading  = $threading;
+
+        $this->result = new rcube_result_index($folder);
+        $this->result->incomplete = true;
+    }
+
+    public function run()
+    {
+        $this->result = $this->search_index();
+    }
+
+    /**
+     * Copy of rcube_imap::search_index()
+     */
+    protected function search_index()
+    {
+        $criteria = $this->search;
+        $charset  = $this->charset;
+        $imap     = $this->worker->get_imap();
+
+        if (!$imap->connected()) {
+            trigger_error("No IMAP connection for $this->folder", E_USER_WARNING);
+
+            if ($this->threading) {
+                return new rcube_result_thread($this->folder);
+            }
+            else {
+                return new rcube_result_index($this->folder);
+            }
+        }
+
+        if ($this->worker->options['skip_deleted'] && !preg_match('/UNDELETED/', $criteria)) {
+            $criteria = 'UNDELETED '.$criteria;
+        }
+
+        // unset CHARSET if criteria string is ASCII, this way
+        // SEARCH won't be re-sent after "unsupported charset" response
+        if ($charset && $charset != 'US-ASCII' && is_ascii($criteria)) {
+            $charset = 'US-ASCII';
+        }
+
+        if ($this->threading) {
+            $threads = $imap->thread($this->folder, $this->threading, $criteria, true, $charset);
+
+            // Error, try with US-ASCII (RFC5256: SORT/THREAD must support US-ASCII and UTF-8,
+            // but I've seen that Courier doesn't support UTF-8)
+            if ($threads->is_error() && $charset && $charset != 'US-ASCII') {
+                $threads = $imap->thread($this->folder, $this->threading,
+                    rcube_imap::convert_criteria($criteria, $charset), true, 'US-ASCII');
+            }
+
+            return $threads;
+        }
+
+        if ($this->sort_field) {
+            $messages = $imap->sort($this->folder, $this->sort_field, $criteria, true, $charset);
+
+            // Error, try with US-ASCII (RFC5256: SORT/THREAD must support US-ASCII and UTF-8,
+            // but I've seen Courier with disabled UTF-8 support)
+            if ($messages->is_error() && $charset && $charset != 'US-ASCII') {
+                $messages = $imap->sort($this->folder, $this->sort_field,
+                    rcube_imap::convert_criteria($criteria, $charset), true, 'US-ASCII');
+            }
+        }
+
+        if (!$messages || $messages->is_error()) {
+            $messages = $imap->search($this->folder,
+                ($charset && $charset != 'US-ASCII' ? "CHARSET $charset " : '') . $criteria, true);
+
+            // Error, try with US-ASCII (some servers may support only US-ASCII)
+            if ($messages->is_error() && $charset && $charset != 'US-ASCII') {
+                $messages = $imap->search($this->folder,
+                    rcube_imap::convert_criteria($criteria, $charset), true);
+            }
+        }
+
+        return $messages;
+    }
+
+    public function get_search_set()
+    {
+        return array(
+            $this->search,
+            $this->result,
+            $this->charset,
+            $this->sort_field,
+            $this->threading,
+        );
+    }
+
+    public function get_result()
+    {
+        return $this->result;
+    }
+}