WordPress 4.4
[autoinstalls/wordpress.git] / wp-includes / canonical.php
index d111514df7eb7388d244c6d37f9e0a83e8cc8eed..cacbdaadfe33ed86a100520a4193453e55bbf456 100644 (file)
  *
  * Search engines consider www.somedomain.com and somedomain.com to be two
  * different URLs when they both go to the same location. This SEO enhancement
- * prevents penality for duplicate content by redirecting all incoming links to
+ * prevents penalty for duplicate content by redirecting all incoming links to
  * one or the other.
  *
  * Prevents redirection for feeds, trackbacks, searches, comment popup, and
- * admin URLs. Does not redirect on IIS, page/post previews, and on form data.
+ * admin URLs. Does not redirect on non-pretty-permalink-supporting IIS 7+,
+ * page/post previews, WP admin, Trackbacks, robots.txt, searches, or on POST
+ * requests.
  *
  * Will also attempt to find the correct link when a user enters a URL that does
  * not exist based on exact WordPress query. Will instead try to parse the URL
  * or query in an attempt to figure the correct page to go to.
  *
  * @since 2.3.0
- * @uses $wp_rewrite
- * @uses $is_IIS
+ *
+ * @global WP_Rewrite $wp_rewrite
+ * @global bool $is_IIS
+ * @global WP_Query $wp_query
+ * @global wpdb $wpdb WordPress database abstraction object.
  *
  * @param string $requested_url Optional. The URL that was requested, used to
  *             figure if redirect is needed.
  * @param bool $do_redirect Optional. Redirect to the new URL.
- * @return null|false|string Null, if redirect not needed. False, if redirect
- *             not needed or the string of the URL
+ * @return string|void The string of the URL, if redirect needed.
  */
 function redirect_canonical( $requested_url = null, $do_redirect = true ) {
-       global $wp_rewrite, $is_IIS, $wp_query, $wpdb;
+       global $wp_rewrite, $is_IIS, $wp_query, $wpdb, $wp;
+
+       if ( isset( $_SERVER['REQUEST_METHOD'] ) && ! in_array( strtoupper( $_SERVER['REQUEST_METHOD'] ), array( 'GET', 'HEAD' ) ) ) {
+               return;
+       }
+
+       // If we're not in wp-admin and the post has been published and preview nonce
+       // is non-existent or invalid then no need for preview in query
+       if ( is_preview() && get_query_var( 'p' ) && 'publish' == get_post_status( get_query_var( 'p' ) ) ) {
+               if ( ! isset( $_GET['preview_id'] )
+                       || ! isset( $_GET['preview_nonce'] )
+                       || ! wp_verify_nonce( $_GET['preview_nonce'], 'post_preview_' . (int) $_GET['preview_id'] ) ) {
+                       $wp_query->is_preview = false;
+               }
+       }
 
-       if ( is_trackback() || is_search() || is_comments_popup() || is_admin() || !empty($_POST) || is_preview() || is_robots() || $is_IIS )
+       if ( is_trackback() || is_search() || is_comments_popup() || is_admin() || is_preview() || is_robots() || ( $is_IIS && !iis7_supports_permalinks() ) ) {
                return;
+       }
 
-       if ( !$requested_url ) {
+       if ( ! $requested_url && isset( $_SERVER['HTTP_HOST'] ) ) {
                // build the URL in the address bar
                $requested_url  = is_ssl() ? 'https://' : 'http://';
                $requested_url .= $_SERVER['HTTP_HOST'];
@@ -48,14 +67,9 @@ function redirect_canonical( $requested_url = null, $do_redirect = true ) {
        }
 
        $original = @parse_url($requested_url);
-       if ( false === $original )
+       if ( false === $original ) {
                return;
-
-       // Some PHP setups turn requests for / into /index.php in REQUEST_URI
-       // See: http://trac.wordpress.org/ticket/5017
-       // See: http://trac.wordpress.org/ticket/7173
-       // Disabled, for now:
-       // $original['path'] = preg_replace('|/index\.php$|', '/', $original['path']);
+       }
 
        $redirect = $original;
        $redirect_url = false;
@@ -66,6 +80,23 @@ function redirect_canonical( $requested_url = null, $do_redirect = true ) {
        if ( !isset($redirect['query']) )
                $redirect['query'] = '';
 
+       // If the original URL ended with non-breaking spaces, they were almost
+       // certainly inserted by accident. Let's remove them, so the reader doesn't
+       // see a 404 error with no obvious cause.
+       $redirect['path'] = preg_replace( '|(%C2%A0)+$|i', '', $redirect['path'] );
+
+       // It's not a preview, so remove it from URL
+       if ( get_query_var( 'preview' ) ) {
+               $redirect['query'] = remove_query_arg( 'preview', $redirect['query'] );
+       }
+
+       if ( is_feed() && ( $id = get_query_var( 'p' ) ) ) {
+               if ( $redirect_url = get_post_comments_feed_link( $id, get_query_var( 'feed' ) ) ) {
+                       $redirect['query'] = _remove_qs_args_if_not_in_url( $redirect['query'], array( 'p', 'page_id', 'attachment_id', 'pagename', 'name', 'post_type', 'feed'), $redirect_url );
+                       $redirect['path'] = parse_url( $redirect_url, PHP_URL_PATH );
+               }
+       }
+
        if ( is_singular() && 1 > $wp_query->post_count && ($id = get_query_var('p')) ) {
 
                $vars = $wpdb->get_results( $wpdb->prepare("SELECT post_type, post_parent FROM $wpdb->posts WHERE ID = %d", $id) );
@@ -75,7 +106,7 @@ function redirect_canonical( $requested_url = null, $do_redirect = true ) {
                                $id = $vars->post_parent;
 
                        if ( $redirect_url = get_permalink($id) )
-                               $redirect['query'] = remove_query_arg(array('p', 'page_id', 'attachment_id', 'post_type'), $redirect['query']);
+                               $redirect['query'] = _remove_qs_args_if_not_in_url( $redirect['query'], array( 'p', 'page_id', 'attachment_id', 'pagename', 'name', 'post_type' ), $redirect_url );
                }
        }
 
@@ -86,20 +117,52 @@ function redirect_canonical( $requested_url = null, $do_redirect = true ) {
                $id = max( get_query_var('p'), get_query_var('page_id'), get_query_var('attachment_id') );
                if ( $id && $redirect_post = get_post($id) ) {
                        $post_type_obj = get_post_type_object($redirect_post->post_type);
-                       if ( $post_type_obj->public ) {
+                       if ( $post_type_obj->public && 'auto-draft' != $redirect_post->post_status ) {
                                $redirect_url = get_permalink($redirect_post);
-                               $redirect['query'] = remove_query_arg(array('p', 'page_id', 'attachment_id', 'post_type'), $redirect['query']);
+                               $redirect['query'] = _remove_qs_args_if_not_in_url( $redirect['query'], array( 'p', 'page_id', 'attachment_id', 'pagename', 'name', 'post_type' ), $redirect_url );
                        }
                }
 
-               if ( ! $redirect_url )
-                       $redirect_url = redirect_guess_404_permalink();
+               if ( get_query_var( 'day' ) && get_query_var( 'monthnum' ) && get_query_var( 'year' ) ) {
+                       $year  = get_query_var( 'year' );
+                       $month = get_query_var( 'monthnum' );
+                       $day   = get_query_var( 'day' );
+                       $date  = sprintf( '%04d-%02d-%02d', $year, $month, $day );
+                       if ( ! wp_checkdate( $month, $day, $year, $date ) ) {
+                               $redirect_url = get_month_link( $year, $month );
+                               $redirect['query'] = _remove_qs_args_if_not_in_url( $redirect['query'], array( 'year', 'monthnum', 'day' ), $redirect_url );
+                       }
+               } elseif ( get_query_var( 'monthnum' ) && get_query_var( 'year' ) && 12 < get_query_var( 'monthnum' ) ) {
+                       $redirect_url = get_year_link( get_query_var( 'year' ) );
+                       $redirect['query'] = _remove_qs_args_if_not_in_url( $redirect['query'], array( 'year', 'monthnum' ), $redirect_url );
+               }
+
+               if ( ! $redirect_url ) {
+                       if ( $redirect_url = redirect_guess_404_permalink() ) {
+                               $redirect['query'] = _remove_qs_args_if_not_in_url( $redirect['query'], array( 'page', 'feed', 'p', 'page_id', 'attachment_id', 'pagename', 'name', 'post_type' ), $redirect_url );
+                       }
+               }
+
+               if ( get_query_var( 'page' ) && $wp_query->post &&
+                       false !== strpos( $wp_query->post->post_content, '<!--nextpage-->' ) ) {
+                       $redirect['path'] = rtrim( $redirect['path'], (int) get_query_var( 'page' ) . '/' );
+                       $redirect['query'] = remove_query_arg( 'page', $redirect['query'] );
+                       $redirect_url = get_permalink( $wp_query->post->ID );
+               }
 
        } elseif ( is_object($wp_rewrite) && $wp_rewrite->using_permalinks() ) {
                // rewriting of old ?p=X, ?m=2004, ?m=200401, ?m=20040101
-               if ( is_attachment() && !empty($_GET['attachment_id']) && ! $redirect_url ) {
-                       if ( $redirect_url = get_attachment_link(get_query_var('attachment_id')) )
-                               $redirect['query'] = remove_query_arg('attachment_id', $redirect['query']);
+               if ( is_attachment() &&
+                       ! array_diff( array_keys( $wp->query_vars ), array( 'attachment', 'attachment_id' ) ) &&
+                       ! $redirect_url ) {
+                       if ( ! empty( $_GET['attachment_id'] ) ) {
+                               $redirect_url = get_attachment_link( get_query_var( 'attachment_id' ) );
+                               if ( $redirect_url ) {
+                                       $redirect['query'] = remove_query_arg( 'attachment_id', $redirect['query'] );
+                               }
+                       } else {
+                               $redirect_url = get_attachment_link();
+                       }
                } elseif ( is_single() && !empty($_GET['p']) && ! $redirect_url ) {
                        if ( $redirect_url = get_permalink(get_query_var('p')) )
                                $redirect['query'] = remove_query_arg(array('p', 'post_type'), $redirect['query']);
@@ -141,66 +204,104 @@ function redirect_canonical( $requested_url = null, $do_redirect = true ) {
                                $redirect['query'] = remove_query_arg('year', $redirect['query']);
                } elseif ( is_author() && !empty($_GET['author']) && preg_match( '|^[0-9]+$|', $_GET['author'] ) ) {
                        $author = get_userdata(get_query_var('author'));
-                       if ( false !== $author && $redirect_url = get_author_posts_url($author->ID, $author->user_nicename) )
-                               $redirect['query'] = remove_query_arg('author', $redirect['query']);
+                       if ( ( false !== $author ) && $wpdb->get_var( $wpdb->prepare( "SELECT ID FROM $wpdb->posts WHERE $wpdb->posts.post_author = %d AND $wpdb->posts.post_status = 'publish' LIMIT 1", $author->ID ) ) ) {
+                               if ( $redirect_url = get_author_posts_url($author->ID, $author->user_nicename) )
+                                       $redirect['query'] = remove_query_arg('author', $redirect['query']);
+                       }
                } elseif ( is_category() || is_tag() || is_tax() ) { // Terms (Tags/categories)
 
                        $term_count = 0;
-                       foreach ( $wp_query->tax_query->queries as $tax_query )
+                       foreach ( $wp_query->tax_query->queried_terms as $tax_query )
                                $term_count += count( $tax_query['terms'] );
 
                        $obj = $wp_query->get_queried_object();
-                       if ( $term_count <= 1 && !empty($obj->term_id) && ( $tax_url = get_term_link((int)$obj->term_id, $obj->taxonomy) ) && !is_wp_error($tax_url) && !empty($redirect['query']) ) {
+                       if ( $term_count <= 1 && !empty($obj->term_id) && ( $tax_url = get_term_link((int)$obj->term_id, $obj->taxonomy) ) && !is_wp_error($tax_url) ) {
                                if ( !empty($redirect['query']) ) {
+                                       // Strip taxonomy query vars off the url.
+                                       $qv_remove = array( 'term', 'taxonomy');
                                        if ( is_category() ) {
-                                               $redirect['query'] = remove_query_arg( array( 'category_name', 'category', 'cat'), $redirect['query']);
+                                               $qv_remove[] = 'category_name';
+                                               $qv_remove[] = 'cat';
                                        } elseif ( is_tag() ) {
-                                               $redirect['query'] = remove_query_arg( array( 'tag', 'tag_id'), $redirect['query']);
-                                       } elseif ( is_tax() ) { // Custom taxonomies will have a custom query var, remove those too:
-                                               $tax = get_taxonomy( $obj->taxonomy );
-                                               if ( false !== $tax->query_var)
-                                                       $redirect['query'] = remove_query_arg($tax->query_var, $redirect['query']);
-                                               else
-                                                       $redirect['query'] = remove_query_arg( array( 'term', 'taxonomy'), $redirect['query']);
+                                               $qv_remove[] = 'tag';
+                                               $qv_remove[] = 'tag_id';
+                                       } else { // Custom taxonomies will have a custom query var, remove those too:
+                                               $tax_obj = get_taxonomy( $obj->taxonomy );
+                                               if ( false !== $tax_obj->query_var )
+                                                       $qv_remove[] = $tax_obj->query_var;
+                                       }
+
+                                       $rewrite_vars = array_diff( array_keys($wp_query->query), array_keys($_GET) );
+
+                                       if ( !array_diff($rewrite_vars, array_keys($_GET))  ) { // Check to see if all the Query vars are coming from the rewrite, none are set via $_GET
+                                               $redirect['query'] = remove_query_arg($qv_remove, $redirect['query']); //Remove all of the per-tax qv's
+
+                                               // Create the destination url for this taxonomy
+                                               $tax_url = parse_url($tax_url);
+                                               if ( ! empty($tax_url['query']) ) { // Taxonomy accessible via ?taxonomy=..&term=.. or any custom qv..
+                                                       parse_str($tax_url['query'], $query_vars);
+                                                       $redirect['query'] = add_query_arg($query_vars, $redirect['query']);
+                                               } else { // Taxonomy is accessible via a "pretty-URL"
+                                                       $redirect['path'] = $tax_url['path'];
+                                               }
+
+                                       } else { // Some query vars are set via $_GET. Unset those from $_GET that exist via the rewrite
+                                               foreach ( $qv_remove as $_qv ) {
+                                                       if ( isset($rewrite_vars[$_qv]) )
+                                                               $redirect['query'] = remove_query_arg($_qv, $redirect['query']);
+                                               }
                                        }
                                }
-                               $tax_url = parse_url($tax_url);
-                               if ( ! empty($tax_url['query']) ) { // Custom taxonomies may only be accessable via ?taxonomy=..&term=..
-                                       parse_str($tax_url['query'], $query_vars);
-                                       $redirect['query'] = add_query_arg($query_vars, $redirect['query']);
-                               } else { // Taxonomy is accessable via a "pretty-URL"
-                                       $redirect['path'] = $tax_url['path'];
-                               }
+
                        }
-               } elseif ( is_single() && strpos($wp_rewrite->permalink_structure, '%category%') !== false ) {
-                       $category = get_category_by_path(get_query_var('category_name'));
+               } elseif ( is_single() && strpos($wp_rewrite->permalink_structure, '%category%') !== false && $cat = get_query_var( 'category_name' ) ) {
+                       $category = get_category_by_path( $cat );
                        $post_terms = wp_get_object_terms($wp_query->get_queried_object_id(), 'category', array('fields' => 'tt_ids'));
                        if ( (!$category || is_wp_error($category)) || ( !is_wp_error($post_terms) && !empty($post_terms) && !in_array($category->term_taxonomy_id, $post_terms) ) )
                                $redirect_url = get_permalink($wp_query->get_queried_object_id());
                }
 
                // Post Paging
-               if ( is_singular() && get_query_var('page') && $redirect_url ) {
+               if ( is_singular() && ! is_front_page() && get_query_var('page') ) {
+                       if ( !$redirect_url )
+                               $redirect_url = get_permalink( get_queried_object_id() );
                        $redirect_url = trailingslashit( $redirect_url ) . user_trailingslashit( get_query_var( 'page' ), 'single_paged' );
                        $redirect['query'] = remove_query_arg( 'page', $redirect['query'] );
                }
 
                // paging and feeds
                if ( get_query_var('paged') || is_feed() || get_query_var('cpage') ) {
-                       while ( preg_match( "#/$wp_rewrite->pagination_base/?[0-9]+?(/+)?$#", $redirect['path'] ) || preg_match( '#/(comments/?)?(feed|rss|rdf|atom|rss2)(/+)?$#', $redirect['path'] ) || preg_match( '#/comment-page-[0-9]+(/+)?$#', $redirect['path'] ) ) {
+                       while ( preg_match( "#/$wp_rewrite->pagination_base/?[0-9]+?(/+)?$#", $redirect['path'] ) || preg_match( '#/(comments/?)?(feed|rss|rdf|atom|rss2)(/+)?$#', $redirect['path'] ) || preg_match( "#/{$wp_rewrite->comments_pagination_base}-[0-9]+(/+)?$#", $redirect['path'] ) ) {
                                // Strip off paging and feed
                                $redirect['path'] = preg_replace("#/$wp_rewrite->pagination_base/?[0-9]+?(/+)?$#", '/', $redirect['path']); // strip off any existing paging
                                $redirect['path'] = preg_replace('#/(comments/?)?(feed|rss2?|rdf|atom)(/+|$)#', '/', $redirect['path']); // strip off feed endings
-                               $redirect['path'] = preg_replace('#/comment-page-[0-9]+?(/+)?$#', '/', $redirect['path']); // strip off any existing comment paging
+                               $redirect['path'] = preg_replace("#/{$wp_rewrite->comments_pagination_base}-[0-9]+?(/+)?$#", '/', $redirect['path']); // strip off any existing comment paging
                        }
 
                        $addl_path = '';
                        if ( is_feed() && in_array( get_query_var('feed'), $wp_rewrite->feeds ) ) {
                                $addl_path = !empty( $addl_path ) ? trailingslashit($addl_path) : '';
-                               if ( get_query_var( 'withcomments' ) )
+                               if ( !is_singular() && get_query_var( 'withcomments' ) )
                                        $addl_path .= 'comments/';
-                               $addl_path .= user_trailingslashit( 'feed/' . ( ( get_default_feed() ==  get_query_var('feed') || 'feed' == get_query_var('feed') ) ? '' : get_query_var('feed') ), 'feed' );
+                               if ( ( 'rss' == get_default_feed() && 'feed' == get_query_var('feed') ) || 'rss' == get_query_var('feed') )
+                                       $addl_path .= user_trailingslashit( 'feed/' . ( ( get_default_feed() == 'rss2' ) ? '' : 'rss2' ), 'feed' );
+                               else
+                                       $addl_path .= user_trailingslashit( 'feed/' . ( ( get_default_feed() ==  get_query_var('feed') || 'feed' == get_query_var('feed') ) ? '' : get_query_var('feed') ), 'feed' );
                                $redirect['query'] = remove_query_arg( 'feed', $redirect['query'] );
+                       } elseif ( is_feed() && 'old' == get_query_var('feed') ) {
+                               $old_feed_files = array(
+                                       'wp-atom.php'         => 'atom',
+                                       'wp-commentsrss2.php' => 'comments_rss2',
+                                       'wp-feed.php'         => get_default_feed(),
+                                       'wp-rdf.php'          => 'rdf',
+                                       'wp-rss.php'          => 'rss2',
+                                       'wp-rss2.php'         => 'rss2',
+                               );
+                               if ( isset( $old_feed_files[ basename( $redirect['path'] ) ] ) ) {
+                                       $redirect_url = get_feed_link( $old_feed_files[ basename( $redirect['path'] ) ] );
+                                       wp_redirect( $redirect_url, 301 );
+                                       die();
+                               }
                        }
 
                        if ( get_query_var('paged') > 0 ) {
@@ -217,18 +318,33 @@ function redirect_canonical( $requested_url = null, $do_redirect = true ) {
                                }
                        }
 
-                       if ( get_option('page_comments') && ( ( 'newest' == get_option('default_comments_page') && get_query_var('cpage') > 0 ) || ( 'newest' != get_option('default_comments_page') && get_query_var('cpage') > 1 ) ) ) {
-                               $addl_path = ( !empty( $addl_path ) ? trailingslashit($addl_path) : '' ) . user_trailingslashit( 'comment-page-' . get_query_var('cpage'), 'commentpaged' );
+                       if ( get_option( 'page_comments' ) && (
+                               ( 'newest' == get_option( 'default_comments_page' ) && get_query_var( 'cpage' ) > 0 ) ||
+                               ( 'newest' != get_option( 'default_comments_page' ) && get_query_var( 'cpage' ) > 1 )
+                       ) ) {
+                               $addl_path = ( !empty( $addl_path ) ? trailingslashit($addl_path) : '' ) . user_trailingslashit( $wp_rewrite->comments_pagination_base . '-' . get_query_var('cpage'), 'commentpaged' );
                                $redirect['query'] = remove_query_arg( 'cpage', $redirect['query'] );
                        }
 
-                       $redirect['path'] = user_trailingslashit( preg_replace('|/index.php/?$|', '/', $redirect['path']) ); // strip off trailing /index.php/
-                       if ( !empty( $addl_path ) && $wp_rewrite->using_index_permalinks() && strpos($redirect['path'], '/index.php/') === false )
-                               $redirect['path'] = trailingslashit($redirect['path']) . 'index.php/';
+                       $redirect['path'] = user_trailingslashit( preg_replace('|/' . preg_quote( $wp_rewrite->index, '|' ) . '/?$|', '/', $redirect['path']) ); // strip off trailing /index.php/
+                       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'] ) ) {
+                       if ( is_multisite() ) {
+                               /** This filter is documented in wp-login.php */
+                               $redirect_url = apply_filters( 'wp_signup_location', network_site_url( 'wp-signup.php' ) );
+                       } else {
+                               $redirect_url = wp_registration_url();
+                       }
+
+                       wp_redirect( $redirect_url, 301 );
+                       die();
+               }
        }
 
        // tack on any additional query vars
@@ -244,6 +360,7 @@ function redirect_canonical( $requested_url = null, $do_redirect = true ) {
                                unset( $_parsed_query['name'] );
                }
 
+               $_parsed_query = rawurlencode_deep( $_parsed_query );
                $redirect_url = add_query_arg( $_parsed_query, $redirect_url );
        }
 
@@ -264,7 +381,7 @@ function redirect_canonical( $requested_url = null, $do_redirect = true ) {
                unset($redirect['port']);
 
        // trailing /index.php
-       $redirect['path'] = preg_replace('|/index.php/*?$|', '/', $redirect['path']);
+       $redirect['path'] = preg_replace('|/' . preg_quote( $wp_rewrite->index, '|' ) . '/*?$|', '/', $redirect['path']);
 
        // Remove trailing spaces from the path
        $redirect['path'] = preg_replace( '#(%20| )+$#', '', $redirect['path'] );
@@ -276,13 +393,16 @@ function redirect_canonical( $requested_url = null, $do_redirect = true ) {
                // 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('/index.php/', '/', $redirect['path']);
+               $redirect['path'] = str_replace( '/' . $wp_rewrite->index . '/', '/', $redirect['path'] );
 
        // trailing slashes
        if ( is_object($wp_rewrite) && $wp_rewrite->using_permalinks() && !is_404() && (!is_front_page() || ( is_front_page() && (get_query_var('paged') > 1) ) ) ) {
@@ -317,7 +437,7 @@ function redirect_canonical( $requested_url = null, $do_redirect = true ) {
                ( strtolower($original['host']) != 'www.' . strtolower($redirect['host']) && 'www.' . strtolower($original['host']) != strtolower($redirect['host']) ) )
                $redirect['host'] = $original['host'];
 
-       $compare_original = array($original['host'], $original['path']);
+       $compare_original = array( $original['host'], $original['path'] );
 
        if ( !empty( $original['port'] ) )
                $compare_original[] = $original['port'];
@@ -325,7 +445,7 @@ function redirect_canonical( $requested_url = null, $do_redirect = true ) {
        if ( !empty( $original['query'] ) )
                $compare_original[] = $original['query'];
 
-       $compare_redirect = array($redirect['host'], $redirect['path']);
+       $compare_redirect = array( $redirect['host'], $redirect['path'] );
 
        if ( !empty( $redirect['port'] ) )
                $compare_redirect[] = $redirect['port'];
@@ -342,8 +462,9 @@ function redirect_canonical( $requested_url = null, $do_redirect = true ) {
                        $redirect_url .= '?' . $redirect['query'];
        }
 
-       if ( !$redirect_url || $redirect_url == $requested_url )
-               return false;
+       if ( ! $redirect_url || $redirect_url == $requested_url ) {
+               return;
+       }
 
        // Hex encoded octets are case-insensitive.
        if ( false !== strpos($requested_url, '%') ) {
@@ -355,11 +476,22 @@ function redirect_canonical( $requested_url = null, $do_redirect = true ) {
                $requested_url = preg_replace_callback('|%[a-fA-F0-9][a-fA-F0-9]|', 'lowercase_octets', $requested_url);
        }
 
-       // Note that you can use the "redirect_canonical" filter to cancel a canonical redirect for whatever reason by returning FALSE
-       $redirect_url = apply_filters('redirect_canonical', $redirect_url, $requested_url);
-
-       if ( !$redirect_url || $redirect_url == $requested_url ) // yes, again -- in case the filter aborted the request
-               return false;
+       /**
+        * Filter the canonical redirect URL.
+        *
+        * Returning false to this filter will cancel the redirect.
+        *
+        * @since 2.3.0
+        *
+        * @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 ) ) {
+               return;
+       }
 
        if ( $do_redirect ) {
                // protect against chained redirects
@@ -369,7 +501,7 @@ function redirect_canonical( $requested_url = null, $do_redirect = true ) {
                } else {
                        // Debug
                        // die("1: $redirect_url<br />2: " . redirect_canonical( $redirect_url, false ) );
-                       return false;
+                       return;
                }
        } else {
                return $redirect_url;
@@ -377,38 +509,126 @@ function redirect_canonical( $requested_url = null, $do_redirect = true ) {
 }
 
 /**
- * Attempts to guess correct post based on query vars.
+ * Removes arguments from a query string if they are not present in a URL
+ * DO NOT use this in plugin code.
+ *
+ * @since 3.4.0
+ * @access private
+ *
+ * @param string $query_string
+ * @param array $args_to_check
+ * @param string $url
+ * @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 );
+               }
+       } else {
+               $query_string = remove_query_arg( $args_to_check, $query_string );
+       }
+       return $query_string;
+}
+
+/**
+ * Strips the #fragment from a URL, if one is present.
+ *
+ * @since 4.4.0
+ *
+ * @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'];
+               }
+               $url .= $parsed_url['path'];
+               if ( ! empty( $parsed_url['query'] ) ) {
+                       $url .= '?' . $parsed_url['query'];
+               }
+       }
+
+       return $url;
+}
+
+/**
+ * Attempts to guess the correct URL based on query vars
  *
  * @since 2.3.0
- * @uses $wpdb
  *
- * @return bool|string Returns False, if it can't find post, returns correct
- *             location on success.
+ * @global wpdb $wpdb WordPress database abstraction object.
+ *
+ * @return false|string The correct URL if one is found. False on failure.
  */
 function redirect_guess_404_permalink() {
        global $wpdb;
 
-       if ( !get_query_var('name') )
-               return false;
-
-       $where = $wpdb->prepare("post_name LIKE %s", like_escape( 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') )
-               $where .= $wpdb->prepare(" AND post_type = %s", get_query_var('post_type'));
-       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'));
-
-       $post_id = $wpdb->get_var("SELECT ID FROM $wpdb->posts WHERE $where AND post_status = 'publish'");
-       if ( !$post_id )
-               return false;
-       return get_permalink($post_id);
+       if ( 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') )
+                       $where .= $wpdb->prepare(" AND post_type = %s", get_query_var('post_type'));
+               else
+                       $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'));
+
+               $post_id = $wpdb->get_var("SELECT ID FROM $wpdb->posts WHERE $where AND post_status = 'publish'");
+               if ( ! $post_id )
+                       return false;
+               if ( get_query_var( 'feed' ) )
+                       return get_post_comments_feed_link( $post_id, get_query_var( 'feed' ) );
+               elseif ( get_query_var( 'page' ) && 1 < get_query_var( 'page' ) )
+                       return trailingslashit( get_permalink( $post_id ) ) . user_trailingslashit( get_query_var( 'page' ), 'single_paged' );
+               else
+                       return get_permalink( $post_id );
+       }
+
+       return false;
 }
 
-add_action('template_redirect', 'redirect_canonical');
+/**
+ *
+ * @global WP_Rewrite $wp_rewrite
+ */
+function wp_redirect_admin_locations() {
+       global $wp_rewrite;
+       if ( ! ( is_404() && $wp_rewrite->using_permalinks() ) )
+               return;
 
-?>
+       $admins = array(
+               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 ) ) {
+               wp_redirect( admin_url() );
+               exit;
+       }
+
+       $logins = array(
+               home_url( 'wp-login.php', 'relative' ),
+               home_url( 'login', 'relative' ),
+               site_url( 'login', 'relative' ),
+       );
+       if ( in_array( untrailingslashit( $_SERVER['REQUEST_URI'] ), $logins ) ) {
+               wp_redirect( wp_login_url() );
+               exit;
+       }
+}