$default_comments_page = get_option( 'default_comments_page' );
if ( get_option( 'page_comments' )
&& ( 'newest' === $default_comments_page && $cpage > 0
|| 'newest' !== $default_comments_page && $cpage > 1 )
$addl_path = ( ! empty( $addl_path ) ? trailingslashit( $addl_path ) : '' );
$addl_path .= user_trailingslashit( $wp_rewrite->comments_pagination_base . '-' . $cpage, 'commentpaged' );
$redirect['query'] = remove_query_arg( 'cpage', $redirect['query'] );
// Strip off trailing /index.php/.
$redirect['path'] = preg_replace( '|/' . preg_quote( $wp_rewrite->index, '|' ) . '/?$|', '/', $redirect['path'] );
$redirect['path'] = user_trailingslashit( $redirect['path'] );
if ( ! empty( $addl_path )
&& $wp_rewrite->using_index_permalinks()
&& strpos( $redirect['path'], '/' . $wp_rewrite->index . '/' ) === false
$redirect['path'] = trailingslashit( $redirect['path'] ) . $wp_rewrite->index . '/';
if ( ! empty( $addl_path ) ) {
$redirect['path'] = trailingslashit( $redirect['path'] ) . $addl_path;
$redirect_url = $redirect['scheme'] . '://' . $redirect['host'] . $redirect['path'];
if ( 'wp-register.php' === basename( $redirect['path'] ) ) {
/** This filter is documented in wp-login.php */
$redirect_url = apply_filters( 'wp_signup_location', network_site_url( 'wp-signup.php' ) );
$redirect_url = wp_registration_url();
wp_redirect( $redirect_url, 301 );
$redirect['query'] = preg_replace( '#^\??&*?#', '', $redirect['query'] );
// Tack on any additional query vars.
if ( $redirect_url && ! empty( $redirect['query'] ) ) {
parse_str( $redirect['query'], $_parsed_query );
$redirect = parse_url( $redirect_url );
if ( ! empty( $_parsed_query['name'] ) && ! empty( $redirect['query'] ) ) {
parse_str( $redirect['query'], $_parsed_redirect_query );
if ( empty( $_parsed_redirect_query['name'] ) ) {
unset( $_parsed_query['name'] );
$_parsed_query = array_combine(
rawurlencode_deep( array_keys( $_parsed_query ) ),
rawurlencode_deep( array_values( $_parsed_query ) )
$redirect_url = add_query_arg( $_parsed_query, $redirect_url );
$redirect = parse_url( $redirect_url );
// www.example.com vs. example.com
$user_home = parse_url( home_url() );
if ( ! empty( $user_home['host'] ) ) {
$redirect['host'] = $user_home['host'];
if ( empty( $user_home['path'] ) ) {
$user_home['path'] = '/';
if ( ! empty( $user_home['port'] ) ) {
$redirect['port'] = $user_home['port'];
unset( $redirect['port'] );
$redirect['path'] = preg_replace( '|/' . preg_quote( $wp_rewrite->index, '|' ) . '/*?$|', '/', $redirect['path'] );
$punctuation_pattern = implode(
'%21', // Exclamation mark.
'%28', // Opening bracket.
'%29', // Closing bracket.
'%7B', // Opening curly bracket.
'%7D', // Closing curly bracket.
'%E2%80%9C', // Opening curly quote.
'%E2%80%9D', // Closing curly quote.
// Remove trailing spaces and end punctuation from the path.
$redirect['path'] = preg_replace( "#($punctuation_pattern)+$#", '', $redirect['path'] );
if ( ! empty( $redirect['query'] ) ) {
// Remove trailing spaces and end punctuation from certain terminating query string args.
$redirect['query'] = preg_replace( "#((^|&)(p|page_id|cat|tag)=[^&]*?)($punctuation_pattern)+$#", '$1', $redirect['query'] );
// Clean up empty query strings.
$redirect['query'] = trim( preg_replace( '#(^|&)(p|page_id|cat|tag)=?(&|$)#', '&', $redirect['query'] ), '&' );
// Redirect obsolete feeds.
$redirect['query'] = preg_replace( '#(^|&)feed=rss(&|$)#', '$1feed=rss2$2', $redirect['query'] );
// Remove redundant leading ampersands.
$redirect['query'] = preg_replace( '#^\??&*?#', '', $redirect['query'] );
// Strip /index.php/ when we're not using PATHINFO permalinks.
if ( ! $wp_rewrite->using_index_permalinks() ) {
$redirect['path'] = str_replace( '/' . $wp_rewrite->index . '/', '/', $redirect['path'] );
if ( is_object( $wp_rewrite ) && $wp_rewrite->using_permalinks()
&& ! is_404() && ( ! is_front_page() || is_front_page() && get_query_var( 'paged' ) > 1 )
if ( get_query_var( 'paged' ) > 0 ) {
foreach ( array( 'single', 'category', 'page', 'day', 'month', 'year', 'home' ) as $type ) {
if ( call_user_func( $func ) ) {
$redirect['path'] = user_trailingslashit( $redirect['path'], $user_ts_type );
} elseif ( is_front_page() ) {
$redirect['path'] = trailingslashit( $redirect['path'] );
// Remove trailing slash for robots.txt or sitemap requests.
|| ! empty( get_query_var( 'sitemap' ) ) || ! empty( get_query_var( 'sitemap-stylesheet' ) )
$redirect['path'] = untrailingslashit( $redirect['path'] );
// Strip multiple slashes out of the URL.
if ( strpos( $redirect['path'], '//' ) > -1 ) {
$redirect['path'] = preg_replace( '|/+|', '/', $redirect['path'] );
// Always trailing slash the Front Page URL.
if ( trailingslashit( $redirect['path'] ) === trailingslashit( $user_home['path'] ) ) {
$redirect['path'] = trailingslashit( $redirect['path'] );
$original_host_low = strtolower( $original['host'] );
$redirect_host_low = strtolower( $redirect['host'] );
// Ignore differences in host capitalization, as this can lead to infinite redirects.
// Only redirect no-www <=> yes-www.
if ( $original_host_low === $redirect_host_low
|| ( 'www.' . $original_host_low !== $redirect_host_low
&& 'www.' . $redirect_host_low !== $original_host_low )
$redirect['host'] = $original['host'];
$compare_original = array( $original['host'], $original['path'] );
if ( ! empty( $original['port'] ) ) {
$compare_original[] = $original['port'];
if ( ! empty( $original['query'] ) ) {
$compare_original[] = $original['query'];
$compare_redirect = array( $redirect['host'], $redirect['path'] );
if ( ! empty( $redirect['port'] ) ) {
$compare_redirect[] = $redirect['port'];
if ( ! empty( $redirect['query'] ) ) {
$compare_redirect[] = $redirect['query'];
if ( $compare_original !== $compare_redirect ) {
$redirect_url = $redirect['scheme'] . '://' . $redirect['host'];
if ( ! empty( $redirect['port'] ) ) {
$redirect_url .= ':' . $redirect['port'];
$redirect_url .= $redirect['path'];
if ( ! empty( $redirect['query'] ) ) {
$redirect_url .= '?' . $redirect['query'];
if ( ! $redirect_url || $redirect_url === $requested_url ) {
// Hex encoded octets are case-insensitive.
if ( false !== strpos( $requested_url, '%' ) ) {
if ( ! function_exists( 'lowercase_octets' ) ) {
* Converts the first hex-encoded octet match to lowercase.
* @param array $matches Hex-encoded octet matches for the requested URL.
* @return string Lowercased version of the first match.
function lowercase_octets( $matches ) {
return strtolower( $matches[0] );
$requested_url = preg_replace_callback( '|%[a-fA-F0-9][a-fA-F0-9]|', 'lowercase_octets', $requested_url );
if ( $redirect_obj instanceof WP_Post ) {
$post_status_obj = get_post_status_object( get_post_status( $redirect_obj ) );
* Unset the redirect object and URL if they are not readable by the user.
* This condition is a little confusing as the condition needs to pass if
* the post is not readable by the user. That's why there are ! (not) conditions
// Private post statuses only redirect if the user can read them.
$post_status_obj->private &&
current_user_can( 'read_post', $redirect_obj->ID )
// For other posts, only redirect if publicly viewable.
! is_post_publicly_viewable( $redirect_obj )
* Filters the canonical redirect URL.
* Returning false to this filter will cancel the redirect.
* @param string $redirect_url The redirect URL.
* @param string $requested_url The requested URL.
$redirect_url = apply_filters( 'redirect_canonical', $redirect_url, $requested_url );
// Yes, again -- in case the filter aborted the request.
if ( ! $redirect_url || strip_fragment_from_url( $redirect_url ) === strip_fragment_from_url( $requested_url ) ) {
// Protect against chained redirects.
if ( ! redirect_canonical( $redirect_url, false ) ) {
wp_redirect( $redirect_url, 301 );
// die("1: $redirect_url<br />2: " . redirect_canonical( $redirect_url, false ) );
* Removes arguments from a query string if they are not present in a URL
* DO NOT use this in plugin code.
* @param string $query_string
* @param array $args_to_check
* @return string The altered query string
function _remove_qs_args_if_not_in_url( $query_string, array $args_to_check, $url ) {
$parsed_url = parse_url( $url );
if ( ! empty( $parsed_url['query'] ) ) {
parse_str( $parsed_url['query'], $parsed_query );
foreach ( $args_to_check as $qv ) {
if ( ! isset( $parsed_query[ $qv ] ) ) {
$query_string = remove_query_arg( $qv, $query_string );
$query_string = remove_query_arg( $args_to_check, $query_string );
* Strips the #fragment from a URL, if one is present.
* @param string $url The URL to strip.
* @return string The altered URL.
function strip_fragment_from_url( $url ) {
$parsed_url = parse_url( $url );
if ( ! empty( $parsed_url['host'] ) ) {
// This mirrors code in redirect_canonical(). It does not handle every case.
$url = $parsed_url['scheme'] . '://' . $parsed_url['host'];
if ( ! empty( $parsed_url['port'] ) ) {
$url .= ':' . $parsed_url['port'];
if ( ! empty( $parsed_url['path'] ) ) {
$url .= $parsed_url['path'];
if ( ! empty( $parsed_url['query'] ) ) {
$url .= '?' . $parsed_url['query'];
* Attempts to guess the correct URL for a 404 request based on query vars.
* @global wpdb $wpdb WordPress database abstraction object.
* @return string|false The correct URL if one is found. False on failure.
function redirect_guess_404_permalink() {
* Filters whether to attempt to guess a redirect URL for a 404 request.
* Returning a false value from the filter will disable the URL guessing
* and return early without performing a redirect.
* @param bool $do_redirect_guess Whether to attempt to guess a redirect URL
* for a 404 request. Default true.
if ( false === apply_filters( 'do_redirect_guess_404_permalink', true ) ) {
* Short-circuits the redirect URL guessing for 404 requests.
* Returning a non-null value from the filter will effectively short-circuit
* the URL guessing, returning the passed value instead.
* @param null|string|false $pre Whether to short-circuit guessing the redirect for a 404.
* Default null to continue with the URL guessing.
$pre = apply_filters( 'pre_redirect_guess_404_permalink', null );
if ( get_query_var( 'name' ) ) {
* Filters whether to perform a strict guess for a 404 redirect.
* Returning a truthy value from the filter will redirect only exact post_name matches.
* @param bool $strict_guess Whether to perform a strict guess. Default false (loose guess).
$strict_guess = apply_filters( 'strict_redirect_guess_404_permalink', false );
$where = $wpdb->prepare( 'post_name = %s', get_query_var( 'name' ) );
$where = $wpdb->prepare( 'post_name LIKE %s', $wpdb->esc_like( get_query_var( 'name' ) ) . '%' );
// If any of post_type, year, monthnum, or day are set, use them to refine the query.
if ( get_query_var( 'post_type' ) ) {
if ( is_array( get_query_var( 'post_type' ) ) ) {
// phpcs:ignore WordPress.DB.PreparedSQLPlaceholders.UnfinishedPrepare
$where .= " AND post_type IN ('" . join( "', '", esc_sql( get_query_var( 'post_type' ) ) ) . "')";
$where .= $wpdb->prepare( ' AND post_type = %s', get_query_var( 'post_type' ) );
$where .= " AND post_type IN ('" . implode( "', '", get_post_types( array( 'public' => true ) ) ) . "')";
if ( get_query_var( 'year' ) ) {
$where .= $wpdb->prepare( ' AND YEAR(post_date) = %d', get_query_var( 'year' ) );
if ( get_query_var( 'monthnum' ) ) {
$where .= $wpdb->prepare( ' AND MONTH(post_date) = %d', get_query_var( 'monthnum' ) );
if ( get_query_var( 'day' ) ) {
$where .= $wpdb->prepare( ' AND DAYOFMONTH(post_date) = %d', get_query_var( 'day' ) );
// phpcs:ignore WordPress.DB.PreparedSQL.InterpolatedNotPrepared
$post_id = $wpdb->get_var( "SELECT ID FROM $wpdb->posts WHERE $where AND post_status = 'publish'" );
if ( get_query_var( 'feed' ) ) {
return get_post_comments_feed_link( $post_id, get_query_var( 'feed' ) );
} elseif ( get_query_var( 'page' ) > 1 ) {
return trailingslashit( get_permalink( $post_id ) ) . user_trailingslashit( get_query_var( 'page' ), 'single_paged' );
return get_permalink( $post_id );
* Redirects a variety of shorthand URLs to the admin.
* If a user visits example.com/admin, they'll be redirected to /wp-admin.
* Visiting /login redirects to /wp-login.php, and so on.
* @global WP_Rewrite $wp_rewrite WordPress rewrite component.
function wp_redirect_admin_locations() {
if ( ! ( is_404() && $wp_rewrite->using_permalinks() ) ) {
home_url( 'wp-admin', 'relative' ),
home_url( 'dashboard', 'relative' ),
home_url( 'admin', 'relative' ),
site_url( 'dashboard', 'relative' ),
site_url( 'admin', 'relative' ),
if ( in_array( untrailingslashit( $_SERVER['REQUEST_URI'] ), $admins, true ) ) {
wp_redirect( admin_url() );