restore_current_blog()

Restore the current blog, after calling switch_to_blog().

Description

See also

Return

(bool) True on success, false if we're already on the current blog.

More Information

restore_current_blog() should be called after every switch_to_blog(). If not, a global variable which monitors the switching, $GLOBALS['_wp_switched_stack'], will not be empty even if you use switch_to_blog() to return to the original blog. If $GLOBALS['_wp_switched_stack'] is not empty, WP will think it is in a switched state and can potentially return the wrong URL for the site via wp_upload_dir(). See http://wordpress.stackexchange.com/a/123516/27757

When calling switch_to_blog() repeatedly, either call restore_current_blog() each time, or save the original blog ID until the end and call switch_to_blog() with that and do:

$GLOBALS['_wp_switched_stack'] = array();
$GLOBALS['switched'] = false;

The former is probably preferable, as it is not a hack.

Source

File: wp-includes/ms-blogs.php 

function restore_current_blog() {
	global $wpdb;

	if ( empty( $GLOBALS['_wp_switched_stack'] ) ) {
		return false;
	}

	$new_blog_id  = array_pop( $GLOBALS['_wp_switched_stack'] );
	$prev_blog_id = get_current_blog_id();

	if ( $new_blog_id == $prev_blog_id ) {
		/** This filter is documented in wp-includes/ms-blogs.php */
		do_action( 'switch_blog', $new_blog_id, $prev_blog_id, 'restore' );

		// If we still have items in the switched stack, consider ourselves still 'switched'.
		$GLOBALS['switched'] = ! empty( $GLOBALS['_wp_switched_stack'] );

		return true;
	}

	$wpdb->set_blog_id( $new_blog_id );
	$GLOBALS['blog_id']      = $new_blog_id;
	$GLOBALS['table_prefix'] = $wpdb->get_blog_prefix();

	if ( function_exists( 'wp_cache_switch_to_blog' ) ) {
		wp_cache_switch_to_blog( $new_blog_id );
	} else {
		global $wp_object_cache;

		if ( is_object( $wp_object_cache ) && isset( $wp_object_cache->global_groups ) ) {
			$global_groups = $wp_object_cache->global_groups;
		} else {
			$global_groups = false;
		}

		wp_cache_init();

		if ( function_exists( 'wp_cache_add_global_groups' ) ) {
			if ( is_array( $global_groups ) ) {
				wp_cache_add_global_groups( $global_groups );
			} else {
				wp_cache_add_global_groups( array( 'users', 'userlogins', 'usermeta', 'user_meta', 'useremail', 'userslugs', 'site-transient', 'site-options', 'blog-lookup', 'blog-details', 'rss', 'global-posts', 'blog-id-cache', 'networks', 'sites', 'site-details', 'blog_meta' ) );
			}

			wp_cache_add_non_persistent_groups( array( 'counts', 'plugins' ) );
		}
	}

	/** This filter is documented in wp-includes/ms-blogs.php */
	do_action( 'switch_blog', $new_blog_id, $prev_blog_id, 'restore' );

	// If we still have items in the switched stack, consider ourselves still 'switched'.
	$GLOBALS['switched'] = ! empty( $GLOBALS['_wp_switched_stack'] );

	return true;
}

Uses

Uses Description
wp-includes/cache.php: wp_cache_switch_to_blog()

Switches the internal blog ID.
wp-includes/cache.php: wp_cache_init()

Sets up Object Cache Global and assigns it.
wp-includes/cache.php: wp_cache_add_global_groups()

Adds a group or set of groups to the list of global groups.
wp-includes/cache.php: wp_cache_add_non_persistent_groups()

Adds a group or set of groups to the list of non-persistent groups.
wp-includes/load.php: get_current_blog_id()

Retrieve the current site ID.
wp-includes/plugin.php: do_action()

Calls the callback functions that have been added to an action hook.
wp-includes/ms-blogs.php: switch_blog

Fires when the blog is switched.
wp-includes/wp-db.php: wpdb::set_blog_id()

Sets blog ID.
wp-includes/wp-db.php: wpdb::get_blog_prefix()

Gets blog prefix.

Used By

Used By Description
wp-includes/ms-site.php: wp_initialize_site()

Runs the initialization routine for a given site.
wp-includes/ms-site.php: wp_uninitialize_site()

Runs the uninitialization routine for a given site.
wp-includes/ms-site.php: wp_is_site_initialized()

Checks whether a site is initialized.
wp-includes/embed.php: get_oembed_response_data_for_url()

Retrieves the oEmbed response data for a given URL.
wp-includes/class-wp-site.php: WP_Site::get_details()

Retrieves the details for this site.
wp-includes/general-template.php: has_custom_logo()

Determines whether the site has a custom logo.
wp-includes/general-template.php: get_custom_logo()

Returns a custom logo, linked to home unless the theme supports removing the link on the home page.
wp-includes/user.php: wp_get_users_with_no_role()

Get the user IDs of all users with no role on this site.
wp-includes/general-template.php: get_site_icon_url()

Returns the Site Icon URL.
wp-admin/includes/class-wp-ms-sites-list-table.php: WP_MS_Sites_List_Table::column_blogname()

Handles the site name column output.
wp-signup.php: confirm_another_blog_signup()

Confirm a new site signup.
wp-admin/includes/ms.php: wpmu_delete_user()

Delete a user from the network and remove from all sites.
wp-admin/includes/ms.php: upload_space_setting()

Displays the site upload space quota setting form on the Edit Site Settings screen.
wp-admin/includes/ms.php: wpmu_delete_blog()

Delete a site.
wp-admin/includes/class-wp-users-list-table.php: WP_Users_List_Table::get_views()

Return an associative array listing all the views that can be used with this table.
wp-includes/class-wp-user.php: WP_User::get_role_caps()

Retrieves all of the capabilities of the user’s roles, and merges them with individual user capabilities.
wp-includes/capabilities.php: current_user_can_for_blog()

Returns whether the current user has the specified capability for a given site.
wp-includes/class-wp-theme.php: WP_Theme::get_allowed_on_site()

Returns array of stylesheet names of themes allowed on the site.
wp-includes/link-template.php: get_home_url()

Retrieves the URL for a given site where the front end is accessible.
wp-includes/link-template.php: get_site_url()

Retrieves the URL for a given site where WordPress application files (e.g. wp-blog-header.php or the wp-admin/ folder) are accessible.
wp-includes/admin-bar.php: wp_admin_bar_my_sites_menu()

Add the “My Sites/[Site Name]” menu and all submenus.
wp-includes/user.php: count_users()

Count number of users who have each of the user roles.
wp-includes/ms-functions.php: newblog_notify_siteadmin()

Notifies the network admin that a new site has been activated.
wp-includes/ms-deprecated.php: create_empty_blog()

Create an empty blog.
wp-includes/ms-functions.php: get_blog_post()

Gets a blog post from any site on the network.
wp-includes/ms-functions.php: add_user_to_blog()

Adds a user to a blog, along with specifying the user’s role.
wp-includes/ms-functions.php: remove_user_from_blog()

Remove a user from a blog.
wp-includes/ms-functions.php: get_blog_permalink()

Get the permalink for a post on another blog.
wp-includes/ms-blogs.php: get_blog_option()

Retrieve option value for a given blog id based on name of option.
wp-includes/ms-blogs.php: add_blog_option()

Add a new option for a given blog ID.
wp-includes/ms-blogs.php: delete_blog_option()

Removes option by name for a given blog ID. Prevents removal of protected WordPress options.
wp-includes/ms-blogs.php: update_blog_option()

Update an option for a particular blog.
wp-includes/ms-blogs.php: get_blog_details()

Retrieve the details for a blog from the blogs table and blog options.
wp-includes/class-wp-xmlrpc-server.php: wp_xmlrpc_server::wp_getUsersBlogs()

Retrieve the blogs of the user.

Changelog

Version Description
MU (3.0.0) Introduced.

© 2003–2021 WordPress Foundation
Licensed under the GNU GPLv2+ License.
https://developer.wordpress.org/reference/functions/restore_current_blog