Index: src/wp-includes/functions.php =================================================================== --- src/wp-includes/functions.php (revision 41059) +++ src/wp-includes/functions.php (working copy) @@ -4386,19 +4386,70 @@ * Determine whether a site is the main site of the current network. * * @since 3.0.0 + * @since 4.9.0 The $network_id parameter has been added. * - * @param int $site_id Optional. Site ID to test. Defaults to current site. + * @param int $site_id Optional. Site ID to test. Defaults to current site. + * @param int $network_id Optional. Network ID of the network to check for. + * Defaults to current network. * @return bool True if $site_id is the main site of the network, or if not * running Multisite. */ -function is_main_site( $site_id = null ) { - if ( ! is_multisite() ) +function is_main_site( $site_id = null, $network_id = null ) { + if ( ! is_multisite() ) { return true; + } - if ( ! $site_id ) + if ( ! $site_id ) { $site_id = get_current_blog_id(); + } + + $site_id = (int) $site_id; + + return $site_id === get_main_site_id( $network_id ); +} + +/** + * Gets the main site ID. + * + * @since 4.9.0 + * + * @param int $network_id Optional. The ID of the network for which to get the main site. + * Defaults to the current network. + * @return int The ID of the main site. + */ +function get_main_site_id( $network_id = null ) { + if ( ! is_multisite() ) { + return 1; + } + + $network = get_network( $network_id ); + if ( ! $network ) { + return 0; + } + + $main_site_id = wp_cache_get( 'network:' . $network->id . ':main_site', 'site-options' ); + if ( false === $main_site_id ) { + $_sites = get_sites( array( + 'fields' => 'ids', + 'number' => 1, + 'domain' => $network->domain, + 'path' => $network->path, + 'network_id' => $network->id, + ) ); + $main_site_id = ! empty( $_sites ) ? array_shift( $_sites ) : 0; - return (int) $site_id === (int) get_network()->site_id; + wp_cache_add( 'network:' . $network->id . ':main_site', $main_site_id, 'site-options' ); + } + + /** + * Filters the main site ID. + * + * @since 4.9.0 + * + * @param int $main_site_id The ID of the main site. + * @param int $network_id The ID of the network for which the main site was detected. + */ + return (int) apply_filters( 'get_main_site_id', $main_site_id, $network->id ); } /** Index: src/wp-includes/ms-load.php =================================================================== --- src/wp-includes/ms-load.php (revision 41059) +++ src/wp-includes/ms-load.php (working copy) @@ -135,7 +135,7 @@ /** * Retrieves the closest matching site object by its domain and path. - * + * * This will not necessarily return an exact match for a domain and path. Instead, it * breaks the domain and path into pieces that are then used to match the closest * possibility from a query. @@ -426,10 +426,8 @@ if ( empty( $current_site->blog_id ) ) { if ( $current_blog->domain === $current_site->domain && $current_blog->path === $current_site->path ) { $current_site->blog_id = $current_blog->blog_id; - } elseif ( ! $current_site->blog_id = wp_cache_get( 'network:' . $current_site->id . ':main_site', 'site-options' ) ) { - $current_site->blog_id = $wpdb->get_var( $wpdb->prepare( "SELECT blog_id FROM $wpdb->blogs WHERE domain = %s AND path = %s", - $current_site->domain, $current_site->path ) ); - wp_cache_add( 'network:' . $current_site->id . ':main_site', $current_site->blog_id, 'site-options' ); + } else { + $current_site->blog_id = get_main_site_id( $current_site->id ); } } Index: tests/phpunit/tests/multisite/site.php =================================================================== --- tests/phpunit/tests/multisite/site.php (revision 41059) +++ tests/phpunit/tests/multisite/site.php (working copy) @@ -741,6 +741,107 @@ restore_current_blog(); } + /** + * @ticket 29684 + */ + function test_is_main_site_different_network() { + $args = array( + 'domain' => 'wordpress.org', + 'path' => '/', + ); + + $network_id = self::factory()->network->create( $args ); + + $args['site_id'] = $network_id; + + $site_id = self::factory()->blog->create( $args ); + $other_site_id = self::factory()->blog->create( array_merge( $args, array( + 'path' => '/foo/', + ) ) ); + + $this->assertTrue( is_main_site( $site_id, $network_id ) ); + } + + /** + * @ticket 29684 + */ + function test_get_main_site_id() { + $this->assertSame( get_current_blog_id(), get_main_site_id() ); + } + + /** + * @ticket 29684 + */ + function test_get_main_site_id_switched() { + $main_site_id = get_current_blog_id(); + + $other_site_id = self::factory()->blog->create(); + switch_to_blog( $other_site_id ); + + $result = get_main_site_id(); + + restore_current_blog(); + + $this->assertSame( $main_site_id, $result ); + } + + /** + * @ticket 29684 + */ + function test_get_main_site_id_different_network() { + $args = array( + 'domain' => 'wordpress.org', + 'path' => '/', + ); + + $network_id = self::factory()->network->create( $args ); + + $args['site_id'] = $network_id; + + $site_id = self::factory()->blog->create( $args ); + $other_site_id = self::factory()->blog->create( array_merge( $args, array( + 'path' => '/foo/', + ) ) ); + + $this->assertSame( $site_id, get_main_site_id( $network_id ) ); + } + + /** + * @ticket 29684 + */ + function test_get_main_site_id_different_network_without_site() { + $args = array( + 'domain' => 'wordpress.org', + 'path' => '/', + ); + + $network_id = self::factory()->network->create( $args ); + + $this->assertSame( 0, get_main_site_id( $network_id ) ); + } + + /** + * @ticket 29684 + */ + function test_get_main_site_id_invalid_network() { + $this->assertSame( 0, get_main_site_id( 333 ) ); + } + + /** + * @ticket 29684 + */ + function test_get_main_site_id_filtered() { + add_filter( 'get_main_site_id', array( $this, 'filter_get_main_site_id' ) ); + $result = get_main_site_id(); + remove_filter( 'get_main_site_id', array( $this, 'filter_get_main_site_id' ) ); + + $this->assertSame( 333, $result ); + } + + function filter_get_main_site_id( $main_site_id ) { + return 333; + } + function test_switch_upload_dir() { $this->assertTrue( is_main_site() );