wp-includes/canonical.php

   1 <?php
   2 /**
   3  * Canonical API to handle WordPress Redirecting
   4  *
   5  * Based on "Permalink Redirect" from Scott Yang and "Enforce www. Preference"
   6  * by Mark Jaquith
   7  *
   8  * @package WordPress
   9  * @since 2.3.0
  10  */
  11
  12 /**
  13  * Redirects incoming links to the proper URL based on the site url.
  14  *
  15  * Search engines consider www.somedomain.com and somedomain.com to be two
  16  * different URLs when they both go to the same location. This SEO enhancement
  17  * prevents penalty for duplicate content by redirecting all incoming links to
  18  * one or the other.
  19  *
  20  * Prevents redirection for feeds, trackbacks, searches, comment popup, and
  21  * admin URLs. Does not redirect on non-pretty-permalink-supporting IIS 7+,
  22  * page/post previews, WP admin, Trackbacks, robots.txt, searches, or on POST
  23  * requests.
  24  *
  25  * Will also attempt to find the correct link when a user enters a URL that does
  26  * not exist based on exact WordPress query. Will instead try to parse the URL
  27  * or query in an attempt to figure the correct page to go to.
  28  *
  29  * @since 2.3.0
  30  *
  31  * @global WP_Rewrite $wp_rewrite
  32  * @global bool $is_IIS
  33  * @global WP_Query $wp_query
  34  * @global wpdb $wpdb
  35  *
  36  * @param string $requested_url Optional. The URL that was requested, used to
  37  *              figure if redirect is needed.
  38  * @param bool $do_redirect Optional. Redirect to the new URL.
  39  * @return string|void The string of the URL, if redirect needed.
  40  */
  41 function redirect_canonical( $requested_url = null, $do_redirect = true ) {
  42         global $wp_rewrite, $is_IIS, $wp_query, $wpdb;
  43
  44         if ( isset( $_SERVER['REQUEST_METHOD'] ) && ! in_array( strtoupper( $_SERVER['REQUEST_METHOD'] ), array( 'GET', 'HEAD' ) ) ) {
  45                 return;
  46         }
  47
  48         // If we're not in wp-admin and the post has been published and preview nonce
  49         // is non-existent or invalid then no need for preview in query
  50         if ( is_preview() && get_query_var( 'p' ) && 'publish' == get_post_status( get_query_var( 'p' ) ) ) {
  51                 if ( ! isset( $_GET['preview_id'] )
  52                         || ! isset( $_GET['preview_nonce'] )
  53                         || ! wp_verify_nonce( $_GET['preview_nonce'], 'post_preview_' . (int) $_GET['preview_id'] ) ) {
  54                         $wp_query->is_preview = false;
  55                 }
  56         }
  57
  58         if ( is_trackback() || is_search() || is_comments_popup() || is_admin() || is_preview() || is_robots() || ( $is_IIS && !iis7_supports_permalinks() ) ) {
  59                 return;
  60         }
  61
  62         if ( !$requested_url ) {
  63                 // build the URL in the address bar
  64                 $requested_url  = is_ssl() ? 'https://' : 'http://';
  65                 $requested_url .= $_SERVER['HTTP_HOST'];
  66                 $requested_url .= $_SERVER['REQUEST_URI'];
  67         }
  68
  69         $original = @parse_url($requested_url);
  70         if ( false === $original )
  71                 return;
  72
  73         // Some PHP setups turn requests for / into /index.php in REQUEST_URI
  74         // See: https://core.trac.wordpress.org/ticket/5017
  75         // See: https://core.trac.wordpress.org/ticket/7173
  76         // Disabled, for now:
  77         // $original['path'] = preg_replace('|/index\.php$|', '/', $original['path']);
  78
  79         $redirect = $original;
  80         $redirect_url = false;
  81
  82         // Notice fixing
  83         if ( !isset($redirect['path']) )
  84                 $redirect['path'] = '';
  85         if ( !isset($redirect['query']) )
  86                 $redirect['query'] = '';
  87
  88         // If the original URL ended with non-breaking spaces, they were almost
  89         // certainly inserted by accident. Let's remove them, so the reader doesn't
  90         // see a 404 error with no obvious cause.
  91         $redirect['path'] = preg_replace( '|(%C2%A0)+$|i', '', $redirect['path'] );
  92
  93         // It's not a preview, so remove it from URL
  94         if ( get_query_var( 'preview' ) ) {
  95                 $redirect['query'] = remove_query_arg( 'preview', $redirect['query'] );
  96         }
  97
  98         if ( is_feed() && ( $id = get_query_var( 'p' ) ) ) {
  99                 if ( $redirect_url = get_post_comments_feed_link( $id, get_query_var( 'feed' ) ) ) {
 100                         $redirect['query'] = _remove_qs_args_if_not_in_url( $redirect['query'], array( 'p', 'page_id', 'attachment_id', 'pagename', 'name', 'post_type', 'feed'), $redirect_url );
 101                         $redirect['path'] = parse_url( $redirect_url, PHP_URL_PATH );
 102                 }
 103         }
 104
 105         if ( is_singular() && 1 > $wp_query->post_count && ($id = get_query_var('p')) ) {
 106
 107                 $vars = $wpdb->get_results( $wpdb->prepare("SELECT post_type, post_parent FROM $wpdb->posts WHERE ID = %d", $id) );
 108
 109                 if ( isset($vars[0]) && $vars = $vars[0] ) {
 110                         if ( 'revision' == $vars->post_type && $vars->post_parent > 0 )
 111                                 $id = $vars->post_parent;
 112
 113                         if ( $redirect_url = get_permalink($id) )
 114                                 $redirect['query'] = _remove_qs_args_if_not_in_url( $redirect['query'], array( 'p', 'page_id', 'attachment_id', 'pagename', 'name', 'post_type' ), $redirect_url );
 115                 }
 116         }
 117
 118         // These tests give us a WP-generated permalink
 119         if ( is_404() ) {
 120
 121                 // Redirect ?page_id, ?p=, ?attachment_id= to their respective url's
 122                 $id = max( get_query_var('p'), get_query_var('page_id'), get_query_var('attachment_id') );
 123                 if ( $id && $redirect_post = get_post($id) ) {
 124                         $post_type_obj = get_post_type_object($redirect_post->post_type);
 125                         if ( $post_type_obj->public ) {
 126                                 $redirect_url = get_permalink($redirect_post);
 127                                 $redirect['query'] = _remove_qs_args_if_not_in_url( $redirect['query'], array( 'p', 'page_id', 'attachment_id', 'pagename', 'name', 'post_type' ), $redirect_url );
 128                         }
 129                 }
 130
 131                 if ( get_query_var( 'day' ) && get_query_var( 'monthnum' ) && get_query_var( 'year' ) ) {
 132                         $year  = get_query_var( 'year' );
 133                         $month = get_query_var( 'monthnum' );
 134                         $day   = get_query_var( 'day' );
 135                         $date  = sprintf( '%04d-%02d-%02d', $year, $month, $day );
 136                         if ( ! wp_checkdate( $month, $day, $year, $date ) ) {
 137                                 $redirect_url = get_month_link( $year, $month );
 138                                 $redirect['query'] = _remove_qs_args_if_not_in_url( $redirect['query'], array( 'year', 'monthnum', 'day' ), $redirect_url );
 139                         }
 140                 } elseif ( get_query_var( 'monthnum' ) && get_query_var( 'year' ) && 12 < get_query_var( 'monthnum' ) ) {
 141                         $redirect_url = get_year_link( get_query_var( 'year' ) );
 142                         $redirect['query'] = _remove_qs_args_if_not_in_url( $redirect['query'], array( 'year', 'monthnum' ), $redirect_url );
 143                 }
 144
 145                 if ( ! $redirect_url ) {
 146                         if ( $redirect_url = redirect_guess_404_permalink() ) {
 147                                 $redirect['query'] = _remove_qs_args_if_not_in_url( $redirect['query'], array( 'page', 'feed', 'p', 'page_id', 'attachment_id', 'pagename', 'name', 'post_type' ), $redirect_url );
 148                         }
 149                 }
 150
 151         } elseif ( is_object($wp_rewrite) && $wp_rewrite->using_permalinks() ) {
 152                 // rewriting of old ?p=X, ?m=2004, ?m=200401, ?m=20040101
 153                 if ( is_attachment() && !empty($_GET['attachment_id']) && ! $redirect_url ) {
 154                         if ( $redirect_url = get_attachment_link(get_query_var('attachment_id')) )
 155                                 $redirect['query'] = remove_query_arg('attachment_id', $redirect['query']);
 156                 } elseif ( is_single() && !empty($_GET['p']) && ! $redirect_url ) {
 157                         if ( $redirect_url = get_permalink(get_query_var('p')) )
 158                                 $redirect['query'] = remove_query_arg(array('p', 'post_type'), $redirect['query']);
 159                 } elseif ( is_single() && !empty($_GET['name'])  && ! $redirect_url ) {
 160                         if ( $redirect_url = get_permalink( $wp_query->get_queried_object_id() ) )
 161                                 $redirect['query'] = remove_query_arg('name', $redirect['query']);
 162                 } elseif ( is_page() && !empty($_GET['page_id']) && ! $redirect_url ) {
 163                         if ( $redirect_url = get_permalink(get_query_var('page_id')) )
 164                                 $redirect['query'] = remove_query_arg('page_id', $redirect['query']);
 165                 } elseif ( is_page() && !is_feed() && isset($wp_query->queried_object) && 'page' == get_option('show_on_front') && $wp_query->queried_object->ID == get_option('page_on_front')  && ! $redirect_url ) {
 166                         $redirect_url = home_url('/');
 167                 } elseif ( is_home() && !empty($_GET['page_id']) && 'page' == get_option('show_on_front') && get_query_var('page_id') == get_option('page_for_posts')  && ! $redirect_url ) {
 168                         if ( $redirect_url = get_permalink(get_option('page_for_posts')) )
 169                                 $redirect['query'] = remove_query_arg('page_id', $redirect['query']);
 170                 } elseif ( !empty($_GET['m']) && ( is_year() || is_month() || is_day() ) ) {
 171                         $m = get_query_var('m');
 172                         switch ( strlen($m) ) {
 173                                 case 4: // Yearly
 174                                         $redirect_url = get_year_link($m);
 175                                         break;
 176                                 case 6: // Monthly
 177                                         $redirect_url = get_month_link( substr($m, 0, 4), substr($m, 4, 2) );
 178                                         break;
 179                                 case 8: // Daily
 180                                         $redirect_url = get_day_link(substr($m, 0, 4), substr($m, 4, 2), substr($m, 6, 2));
 181                                         break;
 182                         }
 183                         if ( $redirect_url )
 184                                 $redirect['query'] = remove_query_arg('m', $redirect['query']);
 185                 // now moving on to non ?m=X year/month/day links
 186                 } elseif ( is_day() && get_query_var('year') && get_query_var('monthnum') && !empty($_GET['day']) ) {
 187                         if ( $redirect_url = get_day_link(get_query_var('year'), get_query_var('monthnum'), get_query_var('day')) )
 188                                 $redirect['query'] = remove_query_arg(array('year', 'monthnum', 'day'), $redirect['query']);
 189                 } elseif ( is_month() && get_query_var('year') && !empty($_GET['monthnum']) ) {
 190                         if ( $redirect_url = get_month_link(get_query_var('year'), get_query_var('monthnum')) )
 191                                 $redirect['query'] = remove_query_arg(array('year', 'monthnum'), $redirect['query']);
 192                 } elseif ( is_year() && !empty($_GET['year']) ) {
 193                         if ( $redirect_url = get_year_link(get_query_var('year')) )
 194                                 $redirect['query'] = remove_query_arg('year', $redirect['query']);
 195                 } elseif ( is_author() && !empty($_GET['author']) && preg_match( '|^[0-9]+$|', $_GET['author'] ) ) {
 196                         $author = get_userdata(get_query_var('author'));
 197                         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 ) ) ) {
 198                                 if ( $redirect_url = get_author_posts_url($author->ID, $author->user_nicename) )
 199                                         $redirect['query'] = remove_query_arg('author', $redirect['query']);
 200                         }
 201                 } elseif ( is_category() || is_tag() || is_tax() ) { // Terms (Tags/categories)
 202
 203                         $term_count = 0;
 204                         foreach ( $wp_query->tax_query->queried_terms as $tax_query )
 205                                 $term_count += count( $tax_query['terms'] );
 206
 207                         $obj = $wp_query->get_queried_object();
 208                         if ( $term_count <= 1 && !empty($obj->term_id) && ( $tax_url = get_term_link((int)$obj->term_id, $obj->taxonomy) ) && !is_wp_error($tax_url) ) {
 209                                 if ( !empty($redirect['query']) ) {
 210                                         // Strip taxonomy query vars off the url.
 211                                         $qv_remove = array( 'term', 'taxonomy');
 212                                         if ( is_category() ) {
 213                                                 $qv_remove[] = 'category_name';
 214                                                 $qv_remove[] = 'cat';
 215                                         } elseif ( is_tag() ) {
 216                                                 $qv_remove[] = 'tag';
 217                                                 $qv_remove[] = 'tag_id';
 218                                         } else { // Custom taxonomies will have a custom query var, remove those too:
 219                                                 $tax_obj = get_taxonomy( $obj->taxonomy );
 220                                                 if ( false !== $tax_obj->query_var )
 221                                                         $qv_remove[] = $tax_obj->query_var;
 222                                         }
 223
 224                                         $rewrite_vars = array_diff( array_keys($wp_query->query), array_keys($_GET) );
 225
 226                                         if ( !array_diff($rewrite_vars, array_keys($_GET))  ) { // Check to see if all the Query vars are coming from the rewrite, none are set via $_GET
 227                                                 $redirect['query'] = remove_query_arg($qv_remove, $redirect['query']); //Remove all of the per-tax qv's
 228
 229                                                 // Create the destination url for this taxonomy
 230                                                 $tax_url = parse_url($tax_url);
 231                                                 if ( ! empty($tax_url['query']) ) { // Taxonomy accessible via ?taxonomy=..&term=.. or any custom qv..
 232                                                         parse_str($tax_url['query'], $query_vars);
 233                                                         $redirect['query'] = add_query_arg($query_vars, $redirect['query']);
 234                                                 } else { // Taxonomy is accessible via a "pretty-URL"
 235                                                         $redirect['path'] = $tax_url['path'];
 236                                                 }
 237
 238                                         } else { // Some query vars are set via $_GET. Unset those from $_GET that exist via the rewrite
 239                                                 foreach ( $qv_remove as $_qv ) {
 240                                                         if ( isset($rewrite_vars[$_qv]) )
 241                                                                 $redirect['query'] = remove_query_arg($_qv, $redirect['query']);
 242                                                 }
 243                                         }
 244                                 }
 245
 246                         }
 247                 } elseif ( is_single() && strpos($wp_rewrite->permalink_structure, '%category%') !== false && $cat = get_query_var( 'category_name' ) ) {
 248                         $category = get_category_by_path( $cat );
 249                         $post_terms = wp_get_object_terms($wp_query->get_queried_object_id(), 'category', array('fields' => 'tt_ids'));
 250                         if ( (!$category || is_wp_error($category)) || ( !is_wp_error($post_terms) && !empty($post_terms) && !in_array($category->term_taxonomy_id, $post_terms) ) )
 251                                 $redirect_url = get_permalink($wp_query->get_queried_object_id());
 252                 }
 253
 254                 // Post Paging
 255                 if ( is_singular() && ! is_front_page() && get_query_var('page') ) {
 256                         if ( !$redirect_url )
 257                                 $redirect_url = get_permalink( get_queried_object_id() );
 258                         $redirect_url = trailingslashit( $redirect_url ) . user_trailingslashit( get_query_var( 'page' ), 'single_paged' );
 259                         $redirect['query'] = remove_query_arg( 'page', $redirect['query'] );
 260                 }
 261
 262                 // paging and feeds
 263                 if ( get_query_var('paged') || is_feed() || get_query_var('cpage') ) {
 264                         while ( preg_match( "#/$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'] ) ) {
 265                                 // Strip off paging and feed
 266                                 $redirect['path'] = preg_replace("#/$wp_rewrite->pagination_base/?[0-9]+?(/+)?$#", '/', $redirect['path']); // strip off any existing paging
 267                                 $redirect['path'] = preg_replace('#/(comments/?)?(feed|rss2?|rdf|atom)(/+|$)#', '/', $redirect['path']); // strip off feed endings
 268                                 $redirect['path'] = preg_replace("#/{$wp_rewrite->comments_pagination_base}-[0-9]+?(/+)?$#", '/', $redirect['path']); // strip off any existing comment paging
 269                         }
 270
 271                         $addl_path = '';
 272                         if ( is_feed() && in_array( get_query_var('feed'), $wp_rewrite->feeds ) ) {
 273                                 $addl_path = !empty( $addl_path ) ? trailingslashit($addl_path) : '';
 274                                 if ( !is_singular() && get_query_var( 'withcomments' ) )
 275                                         $addl_path .= 'comments/';
 276                                 if ( ( 'rss' == get_default_feed() && 'feed' == get_query_var('feed') ) || 'rss' == get_query_var('feed') )
 277                                         $addl_path .= user_trailingslashit( 'feed/' . ( ( get_default_feed() == 'rss2' ) ? '' : 'rss2' ), 'feed' );
 278                                 else
 279                                         $addl_path .= user_trailingslashit( 'feed/' . ( ( get_default_feed() ==  get_query_var('feed') || 'feed' == get_query_var('feed') ) ? '' : get_query_var('feed') ), 'feed' );
 280                                 $redirect['query'] = remove_query_arg( 'feed', $redirect['query'] );
 281                         } elseif ( is_feed() && 'old' == get_query_var('feed') ) {
 282                                 $old_feed_files = array(
 283                                         'wp-atom.php'         => 'atom',
 284                                         'wp-commentsrss2.php' => 'comments_rss2',
 285                                         'wp-feed.php'         => get_default_feed(),
 286                                         'wp-rdf.php'          => 'rdf',
 287                                         'wp-rss.php'          => 'rss2',
 288                                         'wp-rss2.php'         => 'rss2',
 289                                 );
 290                                 if ( isset( $old_feed_files[ basename( $redirect['path'] ) ] ) ) {
 291                                         $redirect_url = get_feed_link( $old_feed_files[ basename( $redirect['path'] ) ] );
 292                                         wp_redirect( $redirect_url, 301 );
 293                                         die();
 294                                 }
 295                         }
 296
 297                         if ( get_query_var('paged') > 0 ) {
 298                                 $paged = get_query_var('paged');
 299                                 $redirect['query'] = remove_query_arg( 'paged', $redirect['query'] );
 300                                 if ( !is_feed() ) {
 301                                         if ( $paged > 1 && !is_single() ) {
 302                                                 $addl_path = ( !empty( $addl_path ) ? trailingslashit($addl_path) : '' ) . user_trailingslashit("$wp_rewrite->pagination_base/$paged", 'paged');
 303                                         } elseif ( !is_single() ) {
 304                                                 $addl_path = !empty( $addl_path ) ? trailingslashit($addl_path) : '';
 305                                         }
 306                                 } elseif ( $paged > 1 ) {
 307                                         $redirect['query'] = add_query_arg( 'paged', $paged, $redirect['query'] );
 308                                 }
 309                         }
 310
 311                         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 ) ) ) {
 312                                 $addl_path = ( !empty( $addl_path ) ? trailingslashit($addl_path) : '' ) . user_trailingslashit( $wp_rewrite->comments_pagination_base . '-' . get_query_var('cpage'), 'commentpaged' );
 313                                 $redirect['query'] = remove_query_arg( 'cpage', $redirect['query'] );
 314                         }
 315
 316                         $redirect['path'] = user_trailingslashit( preg_replace('|/' . preg_quote( $wp_rewrite->index, '|' ) . '/?$|', '/', $redirect['path']) ); // strip off trailing /index.php/
 317                         if ( !empty( $addl_path ) && $wp_rewrite->using_index_permalinks() && strpos($redirect['path'], '/' . $wp_rewrite->index . '/') === false )
 318                                 $redirect['path'] = trailingslashit($redirect['path']) . $wp_rewrite->index . '/';
 319                         if ( !empty( $addl_path ) )
 320                                 $redirect['path'] = trailingslashit($redirect['path']) . $addl_path;
 321                         $redirect_url = $redirect['scheme'] . '://' . $redirect['host'] . $redirect['path'];
 322                 }
 323
 324                 if ( 'wp-register.php' == basename( $redirect['path'] ) ) {
 325                         if ( is_multisite() ) {
 326                                 /** This filter is documented in wp-login.php */
 327                                 $redirect_url = apply_filters( 'wp_signup_location', network_site_url( 'wp-signup.php' ) );
 328                         } else {
 329                                 $redirect_url = site_url( 'wp-login.php?action=register' );
 330                         }
 331
 332                         wp_redirect( $redirect_url, 301 );
 333                         die();
 334                 }
 335         }
 336
 337         // tack on any additional query vars
 338         $redirect['query'] = preg_replace( '#^\??&*?#', '', $redirect['query'] );
 339         if ( $redirect_url && !empty($redirect['query']) ) {
 340                 parse_str( $redirect['query'], $_parsed_query );
 341                 $redirect = @parse_url($redirect_url);
 342
 343                 if ( ! empty( $_parsed_query['name'] ) && ! empty( $redirect['query'] ) ) {
 344                         parse_str( $redirect['query'], $_parsed_redirect_query );
 345
 346                         if ( empty( $_parsed_redirect_query['name'] ) )
 347                                 unset( $_parsed_query['name'] );
 348                 }
 349
 350                 $_parsed_query = rawurlencode_deep( $_parsed_query );
 351                 $redirect_url = add_query_arg( $_parsed_query, $redirect_url );
 352         }
 353
 354         if ( $redirect_url )
 355                 $redirect = @parse_url($redirect_url);
 356
 357         // www.example.com vs example.com
 358         $user_home = @parse_url(home_url());
 359         if ( !empty($user_home['host']) )
 360                 $redirect['host'] = $user_home['host'];
 361         if ( empty($user_home['path']) )
 362                 $user_home['path'] = '/';
 363
 364         // Handle ports
 365         if ( !empty($user_home['port']) )
 366                 $redirect['port'] = $user_home['port'];
 367         else
 368                 unset($redirect['port']);
 369
 370         // trailing /index.php
 371         $redirect['path'] = preg_replace('|/' . preg_quote( $wp_rewrite->index, '|' ) . '/*?$|', '/', $redirect['path']);
 372
 373         // Remove trailing spaces from the path
 374         $redirect['path'] = preg_replace( '#(%20| )+$#', '', $redirect['path'] );
 375
 376         if ( !empty( $redirect['query'] ) ) {
 377                 // Remove trailing spaces from certain terminating query string args
 378                 $redirect['query'] = preg_replace( '#((p|page_id|cat|tag)=[^&]*?)(%20| )+$#', '$1', $redirect['query'] );
 379
 380                 // Clean up empty query strings
 381                 $redirect['query'] = trim(preg_replace( '#(^|&)(p|page_id|cat|tag)=?(&|$)#', '&', $redirect['query']), '&');
 382
 383                 // Redirect obsolete feeds
 384                 $redirect['query'] = preg_replace( '#(^|&)feed=rss(&|$)#', '$1feed=rss2$2', $redirect['query'] );
 385
 386                 // Remove redundant leading ampersands
 387                 $redirect['query'] = preg_replace( '#^\??&*?#', '', $redirect['query'] );
 388         }
 389
 390         // strip /index.php/ when we're not using PATHINFO permalinks
 391         if ( !$wp_rewrite->using_index_permalinks() )
 392                 $redirect['path'] = str_replace( '/' . $wp_rewrite->index . '/', '/', $redirect['path'] );
 393
 394         // trailing slashes
 395         if ( is_object($wp_rewrite) && $wp_rewrite->using_permalinks() && !is_404() && (!is_front_page() || ( is_front_page() && (get_query_var('paged') > 1) ) ) ) {
 396                 $user_ts_type = '';
 397                 if ( get_query_var('paged') > 0 ) {
 398                         $user_ts_type = 'paged';
 399                 } else {
 400                         foreach ( array('single', 'category', 'page', 'day', 'month', 'year', 'home') as $type ) {
 401                                 $func = 'is_' . $type;
 402                                 if ( call_user_func($func) ) {
 403                                         $user_ts_type = $type;
 404                                         break;
 405                                 }
 406                         }
 407                 }
 408                 $redirect['path'] = user_trailingslashit($redirect['path'], $user_ts_type);
 409         } elseif ( is_front_page() ) {
 410                 $redirect['path'] = trailingslashit($redirect['path']);
 411         }
 412
 413         // Strip multiple slashes out of the URL
 414         if ( strpos($redirect['path'], '//') > -1 )
 415                 $redirect['path'] = preg_replace('|/+|', '/', $redirect['path']);
 416
 417         // Always trailing slash the Front Page URL
 418         if ( trailingslashit( $redirect['path'] ) == trailingslashit( $user_home['path'] ) )
 419                 $redirect['path'] = trailingslashit($redirect['path']);
 420
 421         // Ignore differences in host capitalization, as this can lead to infinite redirects
 422         // Only redirect no-www <=> yes-www
 423         if ( strtolower($original['host']) == strtolower($redirect['host']) ||
 424                 ( strtolower($original['host']) != 'www.' . strtolower($redirect['host']) && 'www.' . strtolower($original['host']) != strtolower($redirect['host']) ) )
 425                 $redirect['host'] = $original['host'];
 426
 427         $compare_original = array( $original['host'], $original['path'] );
 428
 429         if ( !empty( $original['port'] ) )
 430                 $compare_original[] = $original['port'];
 431
 432         if ( !empty( $original['query'] ) )
 433                 $compare_original[] = $original['query'];
 434
 435         $compare_redirect = array( $redirect['host'], $redirect['path'] );
 436
 437         if ( !empty( $redirect['port'] ) )
 438                 $compare_redirect[] = $redirect['port'];
 439
 440         if ( !empty( $redirect['query'] ) )
 441                 $compare_redirect[] = $redirect['query'];
 442
 443         if ( $compare_original !== $compare_redirect ) {
 444                 $redirect_url = $redirect['scheme'] . '://' . $redirect['host'];
 445                 if ( !empty($redirect['port']) )
 446                         $redirect_url .= ':' . $redirect['port'];
 447                 $redirect_url .= $redirect['path'];
 448                 if ( !empty($redirect['query']) )
 449                         $redirect_url .= '?' . $redirect['query'];
 450         }
 451
 452         if ( ! $redirect_url || $redirect_url == $requested_url ) {
 453                 return;
 454         }
 455
 456         // Hex encoded octets are case-insensitive.
 457         if ( false !== strpos($requested_url, '%') ) {
 458                 if ( !function_exists('lowercase_octets') ) {
 459                         function lowercase_octets($matches) {
 460                                 return strtolower( $matches[0] );
 461                         }
 462                 }
 463                 $requested_url = preg_replace_callback('|%[a-fA-F0-9][a-fA-F0-9]|', 'lowercase_octets', $requested_url);
 464         }
 465
 466         /**
 467          * Filter the canonical redirect URL.
 468          *
 469          * Returning false to this filter will cancel the redirect.
 470          *
 471          * @since 2.3.0
 472          *
 473          * @param string $redirect_url  The redirect URL.
 474          * @param string $requested_url The requested URL.
 475          */
 476         $redirect_url = apply_filters( 'redirect_canonical', $redirect_url, $requested_url );
 477
 478         // yes, again -- in case the filter aborted the request
 479         if ( ! $redirect_url || $redirect_url == $requested_url ) {
 480                 return;
 481         }
 482
 483         if ( $do_redirect ) {
 484                 // protect against chained redirects
 485                 if ( !redirect_canonical($redirect_url, false) ) {
 486                         wp_redirect($redirect_url, 301);
 487                         exit();
 488                 } else {
 489                         // Debug
 490                         // die("1: $redirect_url<br />2: " . redirect_canonical( $redirect_url, false ) );
 491                         return;
 492                 }
 493         } else {
 494                 return $redirect_url;
 495         }
 496 }
 497
 498 /**
 499  * Removes arguments from a query string if they are not present in a URL
 500  * DO NOT use this in plugin code.
 501  *
 502  * @since 3.4.0
 503  * @access private
 504  *
 505  * @param string $query_string
 506  * @param array $args_to_check
 507  * @param string $url
 508  * @return string The altered query string
 509  */
 510 function _remove_qs_args_if_not_in_url( $query_string, Array $args_to_check, $url ) {
 511         $parsed_url = @parse_url( $url );
 512         if ( ! empty( $parsed_url['query'] ) ) {
 513                 parse_str( $parsed_url['query'], $parsed_query );
 514                 foreach ( $args_to_check as $qv ) {
 515                         if ( !isset( $parsed_query[$qv] ) )
 516                                 $query_string = remove_query_arg( $qv, $query_string );
 517                 }
 518         } else {
 519                 $query_string = remove_query_arg( $args_to_check, $query_string );
 520         }
 521         return $query_string;
 522 }
 523
 524 /**
 525  * Attempts to guess the correct URL based on query vars
 526  *
 527  * @since 2.3.0
 528  *
 529  * @global wpdb $wpdb WordPress database abstraction object.
 530  * @global WP_Rewrite $wp_rewrite
 531  *
 532  * @return false|string The correct URL if one is found. False on failure.
 533  */
 534 function redirect_guess_404_permalink() {
 535         global $wpdb, $wp_rewrite;
 536
 537         if ( get_query_var('name') ) {
 538                 $where = $wpdb->prepare("post_name LIKE %s", $wpdb->esc_like( get_query_var('name') ) . '%');
 539
 540                 // if any of post_type, year, monthnum, or day are set, use them to refine the query
 541                 if ( get_query_var('post_type') )
 542                         $where .= $wpdb->prepare(" AND post_type = %s", get_query_var('post_type'));
 543                 else
 544                         $where .= " AND post_type IN ('" . implode( "', '", get_post_types( array( 'public' => true ) ) ) . "')";
 545
 546                 if ( get_query_var('year') )
 547                         $where .= $wpdb->prepare(" AND YEAR(post_date) = %d", get_query_var('year'));
 548                 if ( get_query_var('monthnum') )
 549                         $where .= $wpdb->prepare(" AND MONTH(post_date) = %d", get_query_var('monthnum'));
 550                 if ( get_query_var('day') )
 551                         $where .= $wpdb->prepare(" AND DAYOFMONTH(post_date) = %d", get_query_var('day'));
 552
 553                 $post_id = $wpdb->get_var("SELECT ID FROM $wpdb->posts WHERE $where AND post_status = 'publish'");
 554                 if ( ! $post_id )
 555                         return false;
 556                 if ( get_query_var( 'feed' ) )
 557                         return get_post_comments_feed_link( $post_id, get_query_var( 'feed' ) );
 558                 elseif ( get_query_var( 'page' ) )
 559                         return trailingslashit( get_permalink( $post_id ) ) . user_trailingslashit( get_query_var( 'page' ), 'single_paged' );
 560                 else
 561                         return get_permalink( $post_id );
 562         }
 563
 564         return false;
 565 }
 566
 567 /**
 568  *
 569  * @global WP_Rewrite $wp_rewrite
 570  */
 571 function wp_redirect_admin_locations() {
 572         global $wp_rewrite;
 573         if ( ! ( is_404() && $wp_rewrite->using_permalinks() ) )
 574                 return;
 575
 576         $admins = array(
 577                 home_url( 'wp-admin', 'relative' ),
 578                 home_url( 'dashboard', 'relative' ),
 579                 home_url( 'admin', 'relative' ),
 580                 site_url( 'dashboard', 'relative' ),
 581                 site_url( 'admin', 'relative' ),
 582         );
 583         if ( in_array( untrailingslashit( $_SERVER['REQUEST_URI'] ), $admins ) ) {
 584                 wp_redirect( admin_url() );
 585                 exit;
 586         }
 587
 588         $logins = array(
 589                 home_url( 'wp-login.php', 'relative' ),
 590                 home_url( 'login', 'relative' ),
 591                 site_url( 'login', 'relative' ),
 592         );
 593         if ( in_array( untrailingslashit( $_SERVER['REQUEST_URI'] ), $logins ) ) {
 594                 wp_redirect( site_url( 'wp-login.php', 'login' ) );
 595                 exit;
 596         }
 597 }