Changeset 27935

Timestamp:

04/03/2014 09:57:22 PM (11 years ago)

Author:

nacin

Message:

Database: Fall back from ext/mysqli to ext/mysql if the connection fails.

This allows us to avoid breaking a site that works under ext/mysql but is misconfigured for ext/mysqli.

props pento.
see #21663.

File:

• trunk/src/wp-includes/wp-db.php (modified) (3 diffs)

trunk/src/wp-includes/wp-db.php

@@ -548 +548 @@
      */
     private $use_mysqli = false;
+
+    /**
+     * Whether we've managed to successfully connect at some point
+     *
+     * @since 3.9.0
+     * @access private
+     * @var bool
+     */
+    private $has_connected = false;
 
     /**
@@ -1337 +1346 @@
             if ( $this->dbh->connect_errno ) {
                 $this->dbh = null;
+
+                /* It's possible ext/mysqli is misconfigured. Fall back to ext/mysql if:
+                 *  - We haven't previously connected, and
+                 *  - USE_EXT_MYSQL isn't set to false, and
+                 *  - ext/mysql is loaded.
+                 */
+                $attempt_fallback = true;
+
+                if ( $this->has_connected ) {
+                    $attempt_fallback = false;
+                } else if ( defined( 'USE_EXT_MYSQL' ) && ! USE_EXT_MYSQL ) {
+                    $attempt_fallback = false;
+                } else if ( ! function_exists( 'mysql_connect' ) ) {
+                    $attempt_fallback = false;
+                }
+
+                if ( $attempt_fallback ) {
+                    $this->use_mysqli = false;
+                    $this->db_connect();
+                }
             }
         } else {
@@ -1368 +1397 @@
             return false;
         } else if ( $this->dbh ) {
+            $this->has_connected = true;
             $this->set_charset( $this->dbh );
             $this->set_sql_mode();