* manually, define `WP_PLUGIN_DIR` and `WP_PLUGIN_URL` in `wp-config.php`.

 *

 * @return array Files to include.

 * @since 3.0.0

 *

	 * @since 3.0.0

			wp_die( __( 'This site is no longer available.' ), '', array( 'response' => 410 ) );

			wp_die( sprintf( __( 'This site has not been activated yet. If you are having problems activating your site, please contact <a href="mailto:%1$s">%1$s</a>.' ), str_replace( '@', ' AT ', get_site_option( 'admin_email', 'support@' . get_current_site()->domain ) ) ) );

 * Retrieve a network object by its domain and path.

 *

 * @since 3.9.0

 * @param string   $domain   Domain to check.

 * @param string   $path     Path to check.

 * @param int|null $segments Path segments to use. Defaults to null, or the full path.

 * @return object|bool Network object if successful. False when no network is found.

function get_network_by_path( $domain, $path, $segments = null ) {

	$domains = array( $domain );

	$pieces = explode( '.', $domain );

	/*

	 * It's possible one domain to search is 'com', but it might as well

	 * be 'localhost' or some other locally mapped domain.

	 */

	while ( array_shift( $pieces ) ) {

		if ( $pieces ) {

			$domains[] = implode( '.', $pieces );

		}

	}

	/*

	 * If we've gotten to this function during normal execution, there is

	 * more than one network installed. At this point, who knows how many

	 * we have. Attempt to optimize for the situation where networks are

	 * only domains, thus meaning paths never need to be considered.

	 *

	 * This is a very basic optimization; anything further could have drawbacks

	 * depending on the setup, so this is best done per-install.

	 */

	$using_paths = true;

	if ( wp_using_ext_object_cache() ) {

		$using_paths = wp_cache_get( 'networks_have_paths', 'site-options' );

		if ( false === $using_paths ) {

			$using_paths = (bool) $wpdb->get_var( "SELECT id FROM $wpdb->site WHERE path <> '/' LIMIT 1" );

			wp_cache_add( 'networks_have_paths', (int) $using_paths, 'site-options'  );

		}

	}

	$paths = array();

	if ( $using_paths ) {

		$path_segments = array_filter( explode( '/', trim( $path, "/" ) ) );

		/**

		 * Filter the number of path segments to consider when searching for a site.

		 *

		 * @since 3.9.0

		 *

		 * @param int|null $segments The number of path segments to consider. WordPress by default looks at

		 *                           one path segment. The function default of null only makes sense when you

		 *                           know the requested path should match a network.

		 * @param string   $domain   The requested domain.

		 * @param string   $path     The requested path, in full.

		 */

		$segments = apply_filters( 'network_by_path_segments_count', $segments, $domain, $path );

		if ( null !== $segments && count($path_segments ) > $segments ) {

			$path_segments = array_slice( $path_segments, 0, $segments );

		}

		while ( count( $path_segments ) ) {

			$paths[] = '/' . implode( '/', $path_segments ) . '/';

			array_pop( $path_segments );

		}

		$paths[] = '/';

	/**

	 * Determine a network by its domain and path.

	 *

	 * This allows one to short-circuit the default logic, perhaps by

	 * replacing it with a routine that is more optimal for your setup.

	 *

	 * Return null to avoid the short-circuit. Return false if no network

	 * can be found at the requested domain and path. Otherwise, return

	 * an object from wp_get_network().

	 *

	 * @since 3.9.0

	 *

	 * @param null|bool|object $network  Network value to return by path.

	 * @param string           $domain   The requested domain.

	 * @param string           $path     The requested path, in full.

	 * @param int|null         $segments The suggested number of paths to consult.

	 *                                   Default null, meaning the entire path was to be consulted.

	 * @param array            $paths    The paths to search for, based on $path and $segments.

	 */

	$pre = apply_filters( 'pre_get_network_by_path', null, $domain, $path, $segments, $paths );

	if ( null !== $pre ) {

		return $pre;

	}

	// @todo Consider additional optimization routes, perhaps as an opt-in for plugins.

	// We already have paths covered. What about how far domains should be drilled down (including www)?

	$search_domains = "'" . implode( "', '", $wpdb->_escape( $domains ) ) . "'";

	if ( ! $using_paths ) {

		$network = $wpdb->get_row( "SELECT id, domain, path FROM $wpdb->site

			WHERE domain IN ($search_domains) ORDER BY CHAR_LENGTH(domain) DESC LIMIT 1" );

		if ( $network ) {

			return wp_get_network( $network );

		}

		return false;

	} else {

		$search_paths = "'" . implode( "', '", $wpdb->_escape( $paths ) ) . "'";

		$networks = $wpdb->get_results( "SELECT id, domain, path FROM $wpdb->site

			WHERE domain IN ($search_domains) AND path IN ($search_paths)

			ORDER BY CHAR_LENGTH(domain) DESC, CHAR_LENGTH(path) DESC" );

	}

	/*

	 * Domains are sorted by length of domain, then by length of path.

	 * The domain must match for the path to be considered. Otherwise,

	 * a network with the path of / will suffice.

	 */

	$found = false;

	foreach ( $networks as $network ) {

		if ( $network->domain === $domain || "www.$network->domain" === $domain ) {

			if ( in_array( $network->path, $paths, true ) ) {

				$found = true;

				break;

			}

		}

		if ( $network->path === '/' ) {

			$found = true;

			break;

		}

	}

	if ( $found ) {

		return wp_get_network( $network );

	}

	return false;

 * Retrieve an object containing information about the requested network.

 * @since 3.9.0

 *

 * @param object|int $network The network's database row or ID.

 * @return object|bool Object containing network information if found, false if not.

function wp_get_network( $network ) {

	global $wpdb;

	if ( ! is_object( $network ) ) {

		$network = $wpdb->get_row( $wpdb->prepare( "SELECT * FROM $wpdb->site WHERE id = %d", $network ) );

		if ( ! $network ) {

			return false;

		}

	}

	return $network;

}

/**

 * Retrieve a site object by its domain and path.

 *

 * @since 3.9.0

 *

 * @param string   $domain   Domain to check.

 * @param string   $path     Path to check.

 * @param int|null $segments Path segments to use. Defaults to null, or the full path.

 * @return object|bool Site object if successful. False when no site is found.

 */

function get_site_by_path( $domain, $path, $segments = null ) {

	global $wpdb;

	$path_segments = array_filter( explode( '/', trim( $path, '/' ) ) );

	/**

	 * Filter the number of path segments to consider when searching for a site.

	 *

	 * @since 3.9.0

	 *

	 * @param int|null $segments The number of path segments to consider. WordPress by default looks at

	 *                           one path segment following the network path. The function default of

	 *                           null only makes sense when you know the requested path should match a site.

	 * @param string   $domain   The requested domain.

	 * @param string   $path     The requested path, in full.

	 */

	$segments = apply_filters( 'site_by_path_segments_count', $segments, $domain, $path );

	if ( null !== $segments && count( $path_segments ) > $segments ) {

		$path_segments = array_slice( $path_segments, 0, $segments );

	}

	$paths = array();

	while ( count( $path_segments ) ) {

		$paths[] = '/' . implode( '/', $path_segments ) . '/';

		array_pop( $path_segments );

	$paths[] = '/';

	/**

	 * Determine a site by its domain and path.

	 *

	 * This allows one to short-circuit the default logic, perhaps by

	 * replacing it with a routine that is more optimal for your setup.

	 *

	 * Return null to avoid the short-circuit. Return false if no site

	 * can be found at the requested domain and path. Otherwise, return

	 * a site object.

	 *

	 * @since 3.9.0

	 *

	 * @param null|bool|object $site     Site value to return by path.

	 * @param string           $domain   The requested domain.

	 * @param string           $path     The requested path, in full.

	 * @param int|null         $segments The suggested number of paths to consult.

	 *                                   Default null, meaning the entire path was to be consulted.

	 * @param array            $paths    The paths to search for, based on $path and $segments.

	 */

	$pre = apply_filters( 'pre_get_site_by_path', null, $domain, $path, $segments, $paths );

	if ( null !== $pre ) {

		return $pre;

	/*

	 * @todo

	 * get_blog_details(), caching, etc. Consider alternative optimization routes,

	 * perhaps as an opt-in for plugins, rather than using the pre_* filter.

	 * For example: The segments filter can expand or ignore paths.

	 * If persistent caching is enabled, we could query the DB for a path <> '/'

	 * then cache whether we can just always ignore paths.

	 */

	// Either www or non-www is supported, not both. If a www domain is requested,

	// query for both to provide the proper redirect.

	$domains = array( $domain );

	if ( 'www.' === substr( $domain, 0, 4 ) ) {

		$domains[] = substr( $domain, 4 );

		$search_domains = "'" . implode( "', '", $wpdb->_escape( $domains ) ) . "'";

	}

	if ( count( $paths ) > 1 ) {

		$search_paths = "'" . implode( "', '", $wpdb->_escape( $paths ) ) . "'";

	if ( count( $domains ) > 1 && count( $paths ) > 1 ) {

		$site = $wpdb->get_row( "SELECT * FROM $wpdb->blogs WHERE domain IN ($search_domains) AND path IN ($search_paths) ORDER BY CHAR_LENGTH(domain) DESC, CHAR_LENGTH(path) DESC LIMIT 1" );

	} elseif ( count( $domains ) > 1 ) {

		$sql = $wpdb->prepare( "SELECT * FROM $wpdb->blogs WHERE path = %s", $paths[0] );

		$sql .= " AND domain IN ($search_domains) ORDER BY CHAR_LENGTH(domain) DESC LIMIT 1";

		$site = $wpdb->get_row( $sql );

	} elseif ( count( $paths ) > 1 ) {

		$sql = $wpdb->prepare( "SELECT * FROM $wpdb->blogs WHERE domain = %s", $domains[0] );

		$sql .= " AND path IN ($search_paths) ORDER BY CHAR_LENGTH(path) DESC LIMIT 1";

		$site = $wpdb->get_row( $sql );

	} else {

		$site = $wpdb->get_row( $wpdb->prepare( "SELECT * FROM $wpdb->blogs WHERE domain = %s AND path = %s", $domains[0], $paths[0] ) );

	if ( $site ) {

		// @todo get_blog_details()

		return $site;

	return false;

	if ( ! is_admin() ) {

		dead_db();

	}

	$query = $wpdb->prepare( "SHOW TABLES LIKE %s", $wpdb->esc_like( $wpdb->site ) );

	if ( ! $wpdb->get_var( $query ) ) {

		$msg .= '<p>' . sprintf(

			/* translators: %s: table name */

			__( '<strong>Database tables are missing.</strong> This means that MySQL is not running, WordPress was not installed properly, or someone deleted %s. You really should look at your database now.' ),

			'<code>' . $wpdb->site . '</code>'

		) . '</p>';