Ticket #41722: 41722.2.diff

src/wp-includes/wp-db.php

@@ -1450 +1450 @@
                 if ( $this->use_mysqli ) {
                         $this->dbh = mysqli_init();
 
-                        // mysqli_real_connect doesn't support the host param including a port or socket
-                        // like mysql_connect does. This duplicates how mysql_connect detects a port and/or socket file.
-                        $port = null;
-                        $socket = null;
-                        $host = $this->dbhost;
-                        $port_or_socket = strstr( $host, ':' );
-                        if ( ! empty( $port_or_socket ) ) {
-                                $host = substr( $host, 0, strpos( $host, ':' ) );
-                                $port_or_socket = substr( $port_or_socket, 1 );
-                                if ( 0 !== strpos( $port_or_socket, '/' ) ) {
-                                        $port = intval( $port_or_socket );
-                                        $maybe_socket = strstr( $port_or_socket, ':' );
-                                        if ( ! empty( $maybe_socket ) ) {
-                                                $socket = substr( $maybe_socket, 1 );
-                                        }
-                                } else {
-                                        $socket = $port_or_socket;
-                                }
-                        }
+                        list( $host, $port, $socket ) = $this->parse_db_host( $this->dbhost );
 
                         if ( WP_DEBUG ) {
                                 mysqli_real_connect( $this->dbh, $host, $this->dbuser, $this->dbpassword, null, $port, $socket, $client_flags );
@@ -1560 +1542 @@
         }
 
         /**
+         * Parse the DB_HOST setting to interpret it for mysqli_real_connect.
+         *
+         * mysqli_real_connect doesn't support the host param including a port or
+         * socket like mysql_connect does. This duplicates how mysql_connect detects
+         * a port and/or socket file.
+         *
+         * @since 4.9.0
+         *
+         * @param string $host The DB_HOST setting to parse.
+         *
+         * @return array Array containing the host, the port and the socket, in that
+         *               order.
+         */
+        public function parse_db_host( $host ) {
+                $port    = null;
+                $socket  = null;
+                $is_ipv6 = false;
+
+                // We need to check for an IPv6 address first.
+                // An IPv6 address will always contain at least two colons.
+                if ( substr_count( $host, ':' ) > 1 ) {
+                        $pattern = '/^(?:\[)?(?<host>[0-9a-fA-F:]+)(?:\]:(?<port>[\d]+))?(?:\/(?<socket>.+))?/';
+                        $is_ipv6 = true;
+                } else {
+                        // We seem to be dealing with an IPv4 address.
+                        $pattern = '/^(?:\[)?(?<host>[^:^\/]+)(?::(?<port>[\d]+))?(?:\/(?<socket>.+))?/';
+                }
+
+                $matches = array();
+                $result = preg_match( $pattern, $host, $matches );
+
+                if ( 1 !== $result ) {
+                        // Couldn't parse the address, just return as is to try it out.
+                        return array( $host, $port, $socket );
+                }
+
+                foreach ( array( 'host', 'port', 'socket' ) as $component ) {
+                        if ( array_key_exists( $component, $matches ) ) {
+                                $$component = $matches[$component];
+                        }
+                }
+
+                // If using the `mysqlnd` library, the IPv6 address needs to be
+                // enclosed in square brackets, whereas it doesn't while using the
+                // `libmysqlclient` library.
+                // @see https://bugs.php.net/bug.php?id=67563
+                if ( $is_ipv6 && extension_loaded( 'mysqlnd' ) ) {
+                        $host = "[$host]";
+                }
+
+                return array( $host, $port, $socket );
+        }
+
+        /**
          * Checks that the connection to the database is still up. If not, try to reconnect.
          *
          * If this function is unable to reconnect, it will forcibly die, or if after the