--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/program/lib/Roundcube/rcube_db_mysql.php	Thu Jan 04 15:52:31 2018 -0500
@@ -0,0 +1,239 @@
+<?php
+
+/**
+ +-----------------------------------------------------------------------+
+ | This file is part of the Roundcube Webmail client                     |
+ | Copyright (C) 2005-2012, The Roundcube Dev Team                       |
+ |                                                                       |
+ | 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:                                                              |
+ |   Database wrapper class that implements PHP PDO functions            |
+ |   for MySQL database                                                  |
+ +-----------------------------------------------------------------------+
+ | Author: Aleksander Machniak <alec@alec.pl>                            |
+ +-----------------------------------------------------------------------+
+*/
+
+/**
+ * Database independent query interface
+ *
+ * This is a wrapper for the PHP PDO
+ *
+ * @package    Framework
+ * @subpackage Database
+ */
+class rcube_db_mysql extends rcube_db
+{
+    public $db_provider = 'mysql';
+
+    /**
+     * Object constructor
+     *
+     * @param string $db_dsnw DSN for read/write operations
+     * @param string $db_dsnr Optional DSN for read only operations
+     * @param bool   $pconn   Enables persistent connections
+     */
+    public function __construct($db_dsnw, $db_dsnr = '', $pconn = false)
+    {
+        parent::__construct($db_dsnw, $db_dsnr, $pconn);
+
+        // SQL identifiers quoting
+        $this->options['identifier_start'] = '`';
+        $this->options['identifier_end'] = '`';
+    }
+
+    /**
+     * Driver-specific configuration of database connection
+     *
+     * @param array $dsn DSN for DB connections
+     * @param PDO   $dbh Connection handler
+     */
+    protected function conn_configure($dsn, $dbh)
+    {
+        $dbh->query("SET NAMES 'utf8'");
+    }
+
+    /**
+     * Abstract SQL statement for value concatenation
+     *
+     * @return string SQL statement to be used in query
+     */
+    public function concat(/* col1, col2, ... */)
+    {
+        $args = func_get_args();
+
+        if (is_array($args[0])) {
+            $args = $args[0];
+        }
+
+        return 'CONCAT(' . join(', ', $args) . ')';
+    }
+
+    /**
+     * Returns PDO DSN string from DSN array
+     *
+     * @param array $dsn DSN parameters
+     *
+     * @return string Connection string
+     */
+    protected function dsn_string($dsn)
+    {
+        $params = array();
+        $result = 'mysql:';
+
+        if ($dsn['database']) {
+            $params[] = 'dbname=' . $dsn['database'];
+        }
+
+        if ($dsn['hostspec']) {
+            $params[] = 'host=' . $dsn['hostspec'];
+        }
+
+        if ($dsn['port']) {
+            $params[] = 'port=' . $dsn['port'];
+        }
+
+        if ($dsn['socket']) {
+            $params[] = 'unix_socket=' . $dsn['socket'];
+        }
+
+        $params[] = 'charset=utf8';
+
+        if (!empty($params)) {
+            $result .= implode(';', $params);
+        }
+
+        return $result;
+    }
+
+    /**
+     * Returns driver-specific connection options
+     *
+     * @param array $dsn DSN parameters
+     *
+     * @return array Connection options
+     */
+    protected function dsn_options($dsn)
+    {
+        $result = parent::dsn_options($dsn);
+
+        if (!empty($dsn['key'])) {
+            $result[PDO::MYSQL_ATTR_SSL_KEY] = $dsn['key'];
+        }
+
+        if (!empty($dsn['cipher'])) {
+            $result[PDO::MYSQL_ATTR_SSL_CIPHER] = $dsn['cipher'];
+        }
+
+        if (!empty($dsn['cert'])) {
+            $result[PDO::MYSQL_ATTR_SSL_CERT] = $dsn['cert'];
+        }
+
+        if (!empty($dsn['capath'])) {
+            $result[PDO::MYSQL_ATTR_SSL_CAPATH] = $dsn['capath'];
+        }
+
+        if (!empty($dsn['ca'])) {
+            $result[PDO::MYSQL_ATTR_SSL_CA] = $dsn['ca'];
+        }
+
+        // Always return matching (not affected only) rows count
+        $result[PDO::MYSQL_ATTR_FOUND_ROWS] = true;
+
+        // Enable AUTOCOMMIT mode (#1488902)
+        $result[PDO::ATTR_AUTOCOMMIT] = true;
+
+        return $result;
+    }
+
+    /**
+     * Returns list of tables in a database
+     *
+     * @return array List of all tables of the current database
+     */
+    public function list_tables()
+    {
+        // get tables if not cached
+        if ($this->tables === null) {
+            // first fetch current database name
+            $d = $this->query("SELECT database()");
+            $d = $this->fetch_array($d);
+
+            // get list of tables in current database
+            $q = $this->query("SELECT TABLE_NAME FROM INFORMATION_SCHEMA.TABLES"
+                . " WHERE TABLE_SCHEMA = ? AND TABLE_TYPE = 'BASE TABLE'"
+                . " ORDER BY TABLE_NAME", $d ? $d[0] : '');
+
+            $this->tables = $q ? $q->fetchAll(PDO::FETCH_COLUMN, 0) : array();
+        }
+
+        return $this->tables;
+    }
+
+    /**
+     * Get database runtime variables
+     *
+     * @param string $varname Variable name
+     * @param mixed  $default Default value if variable is not set
+     *
+     * @return mixed Variable value or default
+     */
+    public function get_variable($varname, $default = null)
+    {
+        if (!isset($this->variables)) {
+            $this->variables = array();
+        }
+
+        if (array_key_exists($varname, $this->variables)) {
+            return $this->variables[$varname];
+        }
+
+        // configured value has higher prio
+        $conf_value = rcube::get_instance()->config->get('db_' . $varname);
+        if ($conf_value !== null) {
+            return $this->variables[$varname] = $conf_value;
+        }
+
+        $result = $this->query('SHOW VARIABLES LIKE ?', $varname);
+
+        while ($row = $this->fetch_array($result)) {
+            $this->variables[$row[0]] = $row[1];
+        }
+
+        // not found, use default
+        if (!isset($this->variables[$varname])) {
+            $this->variables[$varname] = $default;
+        }
+
+        return $this->variables[$varname];
+    }
+
+    /**
+     * Handle DB errors, re-issue the query on deadlock errors from InnoDB row-level locking
+     *
+     * @param string Query that triggered the error
+     * @return mixed Result to be stored and returned
+     */
+    protected function handle_error($query)
+    {
+        $error = $this->dbh->errorInfo();
+
+        // retry after "Deadlock found when trying to get lock" errors
+        $retries = 2;
+        while ($error[1] == 1213 && $retries >= 0) {
+            usleep(50000);  // wait 50 ms
+            $result = $this->dbh->query($query);
+            if ($result !== false) {
+                return $result;
+            }
+            $error = $this->dbh->errorInfo();
+            $retries--;
+        }
+
+        return parent::handle_error($query);
+    }
+
+}