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canonical.php (33085B)


      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, and
     21  * admin URLs. Does not redirect on non-pretty-permalink-supporting IIS 7+,
     22  * page/post previews, WP admin, Trackbacks, robots.txt, favicon.ico, searches,
     23  * or on POST 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 WordPress rewrite component.
     32  * @global bool       $is_IIS
     33  * @global WP_Query   $wp_query   WordPress Query object.
     34  * @global wpdb       $wpdb       WordPress database abstraction object.
     35  * @global WP         $wp         Current WordPress environment instance.
     36  *
     37  * @param string $requested_url Optional. The URL that was requested, used to
     38  *                              figure if redirect is needed.
     39  * @param bool   $do_redirect   Optional. Redirect to the new URL.
     40  * @return string|void The string of the URL, if redirect needed.
     41  */
     42 function redirect_canonical( $requested_url = null, $do_redirect = true ) {
     43 	global $wp_rewrite, $is_IIS, $wp_query, $wpdb, $wp;
     44 
     45 	if ( isset( $_SERVER['REQUEST_METHOD'] ) && ! in_array( strtoupper( $_SERVER['REQUEST_METHOD'] ), array( 'GET', 'HEAD' ), true ) ) {
     46 		return;
     47 	}
     48 
     49 	// If we're not in wp-admin and the post has been published and preview nonce
     50 	// is non-existent or invalid then no need for preview in query.
     51 	if ( is_preview() && get_query_var( 'p' ) && 'publish' === get_post_status( get_query_var( 'p' ) ) ) {
     52 		if ( ! isset( $_GET['preview_id'] )
     53 			|| ! isset( $_GET['preview_nonce'] )
     54 			|| ! wp_verify_nonce( $_GET['preview_nonce'], 'post_preview_' . (int) $_GET['preview_id'] )
     55 		) {
     56 			$wp_query->is_preview = false;
     57 		}
     58 	}
     59 
     60 	if ( is_admin() || is_search() || is_preview() || is_trackback() || is_favicon()
     61 		|| ( $is_IIS && ! iis7_supports_permalinks() )
     62 	) {
     63 		return;
     64 	}
     65 
     66 	if ( ! $requested_url && isset( $_SERVER['HTTP_HOST'] ) ) {
     67 		// Build the URL in the address bar.
     68 		$requested_url  = is_ssl() ? 'https://' : 'http://';
     69 		$requested_url .= $_SERVER['HTTP_HOST'];
     70 		$requested_url .= $_SERVER['REQUEST_URI'];
     71 	}
     72 
     73 	$original = parse_url( $requested_url );
     74 	if ( false === $original ) {
     75 		return;
     76 	}
     77 
     78 	$redirect     = $original;
     79 	$redirect_url = false;
     80 	$redirect_obj = false;
     81 
     82 	// Notice fixing.
     83 	if ( ! isset( $redirect['path'] ) ) {
     84 		$redirect['path'] = '';
     85 	}
     86 	if ( ! isset( $redirect['query'] ) ) {
     87 		$redirect['query'] = '';
     88 	}
     89 
     90 	/*
     91 	 * If the original URL ended with non-breaking spaces, they were almost
     92 	 * certainly inserted by accident. Let's remove them, so the reader doesn't
     93 	 * see a 404 error with no obvious cause.
     94 	 */
     95 	$redirect['path'] = preg_replace( '|(%C2%A0)+$|i', '', $redirect['path'] );
     96 
     97 	// It's not a preview, so remove it from URL.
     98 	if ( get_query_var( 'preview' ) ) {
     99 		$redirect['query'] = remove_query_arg( 'preview', $redirect['query'] );
    100 	}
    101 
    102 	$post_id = get_query_var( 'p' );
    103 
    104 	if ( is_feed() && $post_id ) {
    105 		$redirect_url = get_post_comments_feed_link( $post_id, get_query_var( 'feed' ) );
    106 		$redirect_obj = get_post( $post_id );
    107 
    108 		if ( $redirect_url ) {
    109 			$redirect['query'] = _remove_qs_args_if_not_in_url(
    110 				$redirect['query'],
    111 				array( 'p', 'page_id', 'attachment_id', 'pagename', 'name', 'post_type', 'feed' ),
    112 				$redirect_url
    113 			);
    114 
    115 			$redirect['path'] = parse_url( $redirect_url, PHP_URL_PATH );
    116 		}
    117 	}
    118 
    119 	if ( is_singular() && $wp_query->post_count < 1 && $post_id ) {
    120 
    121 		$vars = $wpdb->get_results( $wpdb->prepare( "SELECT post_type, post_parent FROM $wpdb->posts WHERE ID = %d", $post_id ) );
    122 
    123 		if ( ! empty( $vars[0] ) ) {
    124 			$vars = $vars[0];
    125 
    126 			if ( 'revision' === $vars->post_type && $vars->post_parent > 0 ) {
    127 				$post_id = $vars->post_parent;
    128 			}
    129 
    130 			$redirect_url = get_permalink( $post_id );
    131 			$redirect_obj = get_post( $post_id );
    132 
    133 			if ( $redirect_url ) {
    134 				$redirect['query'] = _remove_qs_args_if_not_in_url(
    135 					$redirect['query'],
    136 					array( 'p', 'page_id', 'attachment_id', 'pagename', 'name', 'post_type' ),
    137 					$redirect_url
    138 				);
    139 			}
    140 		}
    141 	}
    142 
    143 	// These tests give us a WP-generated permalink.
    144 	if ( is_404() ) {
    145 
    146 		// Redirect ?page_id, ?p=, ?attachment_id= to their respective URLs.
    147 		$post_id = max( get_query_var( 'p' ), get_query_var( 'page_id' ), get_query_var( 'attachment_id' ) );
    148 
    149 		$redirect_post = $post_id ? get_post( $post_id ) : false;
    150 
    151 		if ( $redirect_post ) {
    152 			$post_type_obj = get_post_type_object( $redirect_post->post_type );
    153 
    154 			if ( $post_type_obj && $post_type_obj->public && 'auto-draft' !== $redirect_post->post_status ) {
    155 				$redirect_url = get_permalink( $redirect_post );
    156 				$redirect_obj = get_post( $redirect_post );
    157 
    158 				$redirect['query'] = _remove_qs_args_if_not_in_url(
    159 					$redirect['query'],
    160 					array( 'p', 'page_id', 'attachment_id', 'pagename', 'name', 'post_type' ),
    161 					$redirect_url
    162 				);
    163 			}
    164 		}
    165 
    166 		$year  = get_query_var( 'year' );
    167 		$month = get_query_var( 'monthnum' );
    168 		$day   = get_query_var( 'day' );
    169 
    170 		if ( $year && $month && $day ) {
    171 			$date = sprintf( '%04d-%02d-%02d', $year, $month, $day );
    172 
    173 			if ( ! wp_checkdate( $month, $day, $year, $date ) ) {
    174 				$redirect_url = get_month_link( $year, $month );
    175 
    176 				$redirect['query'] = _remove_qs_args_if_not_in_url(
    177 					$redirect['query'],
    178 					array( 'year', 'monthnum', 'day' ),
    179 					$redirect_url
    180 				);
    181 			}
    182 		} elseif ( $year && $month && $month > 12 ) {
    183 			$redirect_url = get_year_link( $year );
    184 
    185 			$redirect['query'] = _remove_qs_args_if_not_in_url(
    186 				$redirect['query'],
    187 				array( 'year', 'monthnum' ),
    188 				$redirect_url
    189 			);
    190 		}
    191 
    192 		// Strip off non-existing <!--nextpage--> links from single posts or pages.
    193 		if ( get_query_var( 'page' ) ) {
    194 			$post_id = 0;
    195 
    196 			if ( $wp_query->queried_object instanceof WP_Post ) {
    197 				$post_id = $wp_query->queried_object->ID;
    198 			} elseif ( $wp_query->post ) {
    199 				$post_id = $wp_query->post->ID;
    200 			}
    201 
    202 			if ( $post_id ) {
    203 				$redirect_url = get_permalink( $post_id );
    204 				$redirect_obj = get_post( $post_id );
    205 
    206 				$redirect['path']  = rtrim( $redirect['path'], (int) get_query_var( 'page' ) . '/' );
    207 				$redirect['query'] = remove_query_arg( 'page', $redirect['query'] );
    208 			}
    209 		}
    210 
    211 		if ( ! $redirect_url ) {
    212 			$redirect_url = redirect_guess_404_permalink();
    213 
    214 			if ( $redirect_url ) {
    215 				$redirect['query'] = _remove_qs_args_if_not_in_url(
    216 					$redirect['query'],
    217 					array( 'page', 'feed', 'p', 'page_id', 'attachment_id', 'pagename', 'name', 'post_type' ),
    218 					$redirect_url
    219 				);
    220 			}
    221 		}
    222 	} elseif ( is_object( $wp_rewrite ) && $wp_rewrite->using_permalinks() ) {
    223 
    224 		// Rewriting of old ?p=X, ?m=2004, ?m=200401, ?m=20040101.
    225 		if ( is_attachment()
    226 			&& ! array_diff( array_keys( $wp->query_vars ), array( 'attachment', 'attachment_id' ) )
    227 			&& ! $redirect_url
    228 		) {
    229 			if ( ! empty( $_GET['attachment_id'] ) ) {
    230 				$redirect_url = get_attachment_link( get_query_var( 'attachment_id' ) );
    231 				$redirect_obj = get_post( get_query_var( 'attachment_id' ) );
    232 
    233 				if ( $redirect_url ) {
    234 					$redirect['query'] = remove_query_arg( 'attachment_id', $redirect['query'] );
    235 				}
    236 			} else {
    237 				$redirect_url = get_attachment_link();
    238 				$redirect_obj = get_post();
    239 			}
    240 		} elseif ( is_single() && ! empty( $_GET['p'] ) && ! $redirect_url ) {
    241 			$redirect_url = get_permalink( get_query_var( 'p' ) );
    242 			$redirect_obj = get_post( get_query_var( 'p' ) );
    243 
    244 			if ( $redirect_url ) {
    245 				$redirect['query'] = remove_query_arg( array( 'p', 'post_type' ), $redirect['query'] );
    246 			}
    247 		} elseif ( is_single() && ! empty( $_GET['name'] ) && ! $redirect_url ) {
    248 			$redirect_url = get_permalink( $wp_query->get_queried_object_id() );
    249 			$redirect_obj = get_post( $wp_query->get_queried_object_id() );
    250 
    251 			if ( $redirect_url ) {
    252 				$redirect['query'] = remove_query_arg( 'name', $redirect['query'] );
    253 			}
    254 		} elseif ( is_page() && ! empty( $_GET['page_id'] ) && ! $redirect_url ) {
    255 			$redirect_url = get_permalink( get_query_var( 'page_id' ) );
    256 			$redirect_obj = get_post( get_query_var( 'page_id' ) );
    257 
    258 			if ( $redirect_url ) {
    259 				$redirect['query'] = remove_query_arg( 'page_id', $redirect['query'] );
    260 			}
    261 		} elseif ( is_page() && ! is_feed() && ! $redirect_url
    262 			&& 'page' === get_option( 'show_on_front' ) && get_queried_object_id() === (int) get_option( 'page_on_front' )
    263 		) {
    264 			$redirect_url = home_url( '/' );
    265 		} elseif ( is_home() && ! empty( $_GET['page_id'] ) && ! $redirect_url
    266 			&& 'page' === get_option( 'show_on_front' ) && get_query_var( 'page_id' ) === (int) get_option( 'page_for_posts' )
    267 		) {
    268 			$redirect_url = get_permalink( get_option( 'page_for_posts' ) );
    269 			$redirect_obj = get_post( get_option( 'page_for_posts' ) );
    270 
    271 			if ( $redirect_url ) {
    272 				$redirect['query'] = remove_query_arg( 'page_id', $redirect['query'] );
    273 			}
    274 		} elseif ( ! empty( $_GET['m'] ) && ( is_year() || is_month() || is_day() ) ) {
    275 			$m = get_query_var( 'm' );
    276 
    277 			switch ( strlen( $m ) ) {
    278 				case 4: // Yearly.
    279 					$redirect_url = get_year_link( $m );
    280 					break;
    281 				case 6: // Monthly.
    282 					$redirect_url = get_month_link( substr( $m, 0, 4 ), substr( $m, 4, 2 ) );
    283 					break;
    284 				case 8: // Daily.
    285 					$redirect_url = get_day_link( substr( $m, 0, 4 ), substr( $m, 4, 2 ), substr( $m, 6, 2 ) );
    286 					break;
    287 			}
    288 
    289 			if ( $redirect_url ) {
    290 				$redirect['query'] = remove_query_arg( 'm', $redirect['query'] );
    291 			}
    292 			// Now moving on to non ?m=X year/month/day links.
    293 		} elseif ( is_date() ) {
    294 			$year  = get_query_var( 'year' );
    295 			$month = get_query_var( 'monthnum' );
    296 			$day   = get_query_var( 'day' );
    297 
    298 			if ( is_day() && $year && $month && ! empty( $_GET['day'] ) ) {
    299 				$redirect_url = get_day_link( $year, $month, $day );
    300 
    301 				if ( $redirect_url ) {
    302 					$redirect['query'] = remove_query_arg( array( 'year', 'monthnum', 'day' ), $redirect['query'] );
    303 				}
    304 			} elseif ( is_month() && $year && ! empty( $_GET['monthnum'] ) ) {
    305 				$redirect_url = get_month_link( $year, $month );
    306 
    307 				if ( $redirect_url ) {
    308 					$redirect['query'] = remove_query_arg( array( 'year', 'monthnum' ), $redirect['query'] );
    309 				}
    310 			} elseif ( is_year() && ! empty( $_GET['year'] ) ) {
    311 				$redirect_url = get_year_link( $year );
    312 
    313 				if ( $redirect_url ) {
    314 					$redirect['query'] = remove_query_arg( 'year', $redirect['query'] );
    315 				}
    316 			}
    317 		} elseif ( is_author() && ! empty( $_GET['author'] ) && preg_match( '|^[0-9]+$|', $_GET['author'] ) ) {
    318 			$author = get_userdata( get_query_var( 'author' ) );
    319 
    320 			if ( false !== $author
    321 				&& $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 ) )
    322 			) {
    323 				$redirect_url = get_author_posts_url( $author->ID, $author->user_nicename );
    324 				$redirect_obj = $author;
    325 
    326 				if ( $redirect_url ) {
    327 					$redirect['query'] = remove_query_arg( 'author', $redirect['query'] );
    328 				}
    329 			}
    330 		} elseif ( is_category() || is_tag() || is_tax() ) { // Terms (tags/categories).
    331 			$term_count = 0;
    332 
    333 			foreach ( $wp_query->tax_query->queried_terms as $tax_query ) {
    334 				$term_count += count( $tax_query['terms'] );
    335 			}
    336 
    337 			$obj = $wp_query->get_queried_object();
    338 
    339 			if ( $term_count <= 1 && ! empty( $obj->term_id ) ) {
    340 				$tax_url = get_term_link( (int) $obj->term_id, $obj->taxonomy );
    341 
    342 				if ( $tax_url && ! is_wp_error( $tax_url ) ) {
    343 					if ( ! empty( $redirect['query'] ) ) {
    344 						// Strip taxonomy query vars off the URL.
    345 						$qv_remove = array( 'term', 'taxonomy' );
    346 
    347 						if ( is_category() ) {
    348 							$qv_remove[] = 'category_name';
    349 							$qv_remove[] = 'cat';
    350 						} elseif ( is_tag() ) {
    351 							$qv_remove[] = 'tag';
    352 							$qv_remove[] = 'tag_id';
    353 						} else {
    354 							// Custom taxonomies will have a custom query var, remove those too.
    355 							$tax_obj = get_taxonomy( $obj->taxonomy );
    356 							if ( false !== $tax_obj->query_var ) {
    357 								$qv_remove[] = $tax_obj->query_var;
    358 							}
    359 						}
    360 
    361 						$rewrite_vars = array_diff( array_keys( $wp_query->query ), array_keys( $_GET ) );
    362 
    363 						// Check to see if all the query vars are coming from the rewrite, none are set via $_GET.
    364 						if ( ! array_diff( $rewrite_vars, array_keys( $_GET ) ) ) {
    365 							// Remove all of the per-tax query vars.
    366 							$redirect['query'] = remove_query_arg( $qv_remove, $redirect['query'] );
    367 
    368 							// Create the destination URL for this taxonomy.
    369 							$tax_url = parse_url( $tax_url );
    370 
    371 							if ( ! empty( $tax_url['query'] ) ) {
    372 								// Taxonomy accessible via ?taxonomy=...&term=... or any custom query var.
    373 								parse_str( $tax_url['query'], $query_vars );
    374 								$redirect['query'] = add_query_arg( $query_vars, $redirect['query'] );
    375 							} else {
    376 								// Taxonomy is accessible via a "pretty URL".
    377 								$redirect['path'] = $tax_url['path'];
    378 							}
    379 						} else {
    380 							// Some query vars are set via $_GET. Unset those from $_GET that exist via the rewrite.
    381 							foreach ( $qv_remove as $_qv ) {
    382 								if ( isset( $rewrite_vars[ $_qv ] ) ) {
    383 									$redirect['query'] = remove_query_arg( $_qv, $redirect['query'] );
    384 								}
    385 							}
    386 						}
    387 					}
    388 				}
    389 			}
    390 		} elseif ( is_single() && strpos( $wp_rewrite->permalink_structure, '%category%' ) !== false ) {
    391 			$category_name = get_query_var( 'category_name' );
    392 
    393 			if ( $category_name ) {
    394 				$category = get_category_by_path( $category_name );
    395 
    396 				if ( ! $category || is_wp_error( $category )
    397 					|| ! has_term( $category->term_id, 'category', $wp_query->get_queried_object_id() )
    398 				) {
    399 					$redirect_url = get_permalink( $wp_query->get_queried_object_id() );
    400 					$redirect_obj = get_post( $wp_query->get_queried_object_id() );
    401 				}
    402 			}
    403 		}
    404 
    405 		// Post paging.
    406 		if ( is_singular() && get_query_var( 'page' ) ) {
    407 			$page = get_query_var( 'page' );
    408 
    409 			if ( ! $redirect_url ) {
    410 				$redirect_url = get_permalink( get_queried_object_id() );
    411 				$redirect_obj = get_post( get_queried_object_id() );
    412 			}
    413 
    414 			if ( $page > 1 ) {
    415 				$redirect_url = trailingslashit( $redirect_url );
    416 
    417 				if ( is_front_page() ) {
    418 					$redirect_url .= user_trailingslashit( "$wp_rewrite->pagination_base/$page", 'paged' );
    419 				} else {
    420 					$redirect_url .= user_trailingslashit( $page, 'single_paged' );
    421 				}
    422 			}
    423 
    424 			$redirect['query'] = remove_query_arg( 'page', $redirect['query'] );
    425 		}
    426 
    427 		if ( get_query_var( 'sitemap' ) ) {
    428 			$redirect_url      = get_sitemap_url( get_query_var( 'sitemap' ), get_query_var( 'sitemap-subtype' ), get_query_var( 'paged' ) );
    429 			$redirect['query'] = remove_query_arg( array( 'sitemap', 'sitemap-subtype', 'paged' ), $redirect['query'] );
    430 		} elseif ( get_query_var( 'paged' ) || is_feed() || get_query_var( 'cpage' ) ) {
    431 			// Paging and feeds.
    432 			$paged = get_query_var( 'paged' );
    433 			$feed  = get_query_var( 'feed' );
    434 			$cpage = get_query_var( 'cpage' );
    435 
    436 			while ( preg_match( "#/$wp_rewrite->pagination_base/?[0-9]+?(/+)?$#", $redirect['path'] )
    437 				|| preg_match( '#/(comments/?)?(feed|rss2?|rdf|atom)(/+)?$#', $redirect['path'] )
    438 				|| preg_match( "#/{$wp_rewrite->comments_pagination_base}-[0-9]+(/+)?$#", $redirect['path'] )
    439 			) {
    440 				// Strip off any existing paging.
    441 				$redirect['path'] = preg_replace( "#/$wp_rewrite->pagination_base/?[0-9]+?(/+)?$#", '/', $redirect['path'] );
    442 				// Strip off feed endings.
    443 				$redirect['path'] = preg_replace( '#/(comments/?)?(feed|rss2?|rdf|atom)(/+|$)#', '/', $redirect['path'] );
    444 				// Strip off any existing comment paging.
    445 				$redirect['path'] = preg_replace( "#/{$wp_rewrite->comments_pagination_base}-[0-9]+?(/+)?$#", '/', $redirect['path'] );
    446 			}
    447 
    448 			$addl_path    = '';
    449 			$default_feed = get_default_feed();
    450 
    451 			if ( is_feed() && in_array( $feed, $wp_rewrite->feeds, true ) ) {
    452 				$addl_path = ! empty( $addl_path ) ? trailingslashit( $addl_path ) : '';
    453 
    454 				if ( ! is_singular() && get_query_var( 'withcomments' ) ) {
    455 					$addl_path .= 'comments/';
    456 				}
    457 
    458 				if ( ( 'rss' === $default_feed && 'feed' === $feed ) || 'rss' === $feed ) {
    459 					$format = ( 'rss2' === $default_feed ) ? '' : 'rss2';
    460 				} else {
    461 					$format = ( $default_feed === $feed || 'feed' === $feed ) ? '' : $feed;
    462 				}
    463 
    464 				$addl_path .= user_trailingslashit( 'feed/' . $format, 'feed' );
    465 
    466 				$redirect['query'] = remove_query_arg( 'feed', $redirect['query'] );
    467 			} elseif ( is_feed() && 'old' === $feed ) {
    468 				$old_feed_files = array(
    469 					'wp-atom.php'         => 'atom',
    470 					'wp-commentsrss2.php' => 'comments_rss2',
    471 					'wp-feed.php'         => $default_feed,
    472 					'wp-rdf.php'          => 'rdf',
    473 					'wp-rss.php'          => 'rss2',
    474 					'wp-rss2.php'         => 'rss2',
    475 				);
    476 
    477 				if ( isset( $old_feed_files[ basename( $redirect['path'] ) ] ) ) {
    478 					$redirect_url = get_feed_link( $old_feed_files[ basename( $redirect['path'] ) ] );
    479 
    480 					wp_redirect( $redirect_url, 301 );
    481 					die();
    482 				}
    483 			}
    484 
    485 			if ( $paged > 0 ) {
    486 				$redirect['query'] = remove_query_arg( 'paged', $redirect['query'] );
    487 
    488 				if ( ! is_feed() ) {
    489 					if ( ! is_single() ) {
    490 						$addl_path = ! empty( $addl_path ) ? trailingslashit( $addl_path ) : '';
    491 
    492 						if ( $paged > 1 ) {
    493 							$addl_path .= user_trailingslashit( "$wp_rewrite->pagination_base/$paged", 'paged' );
    494 						}
    495 					}
    496 				} elseif ( $paged > 1 ) {
    497 					$redirect['query'] = add_query_arg( 'paged', $paged, $redirect['query'] );
    498 				}
    499 			}
    500 
    501 			$default_comments_page = get_option( 'default_comments_page' );
    502 
    503 			if ( get_option( 'page_comments' )
    504 				&& ( 'newest' === $default_comments_page && $cpage > 0
    505 					|| 'newest' !== $default_comments_page && $cpage > 1 )
    506 			) {
    507 				$addl_path  = ( ! empty( $addl_path ) ? trailingslashit( $addl_path ) : '' );
    508 				$addl_path .= user_trailingslashit( $wp_rewrite->comments_pagination_base . '-' . $cpage, 'commentpaged' );
    509 
    510 				$redirect['query'] = remove_query_arg( 'cpage', $redirect['query'] );
    511 			}
    512 
    513 			// Strip off trailing /index.php/.
    514 			$redirect['path'] = preg_replace( '|/' . preg_quote( $wp_rewrite->index, '|' ) . '/?$|', '/', $redirect['path'] );
    515 			$redirect['path'] = user_trailingslashit( $redirect['path'] );
    516 
    517 			if ( ! empty( $addl_path )
    518 				&& $wp_rewrite->using_index_permalinks()
    519 				&& strpos( $redirect['path'], '/' . $wp_rewrite->index . '/' ) === false
    520 			) {
    521 				$redirect['path'] = trailingslashit( $redirect['path'] ) . $wp_rewrite->index . '/';
    522 			}
    523 
    524 			if ( ! empty( $addl_path ) ) {
    525 				$redirect['path'] = trailingslashit( $redirect['path'] ) . $addl_path;
    526 			}
    527 
    528 			$redirect_url = $redirect['scheme'] . '://' . $redirect['host'] . $redirect['path'];
    529 		}
    530 
    531 		if ( 'wp-register.php' === basename( $redirect['path'] ) ) {
    532 			if ( is_multisite() ) {
    533 				/** This filter is documented in wp-login.php */
    534 				$redirect_url = apply_filters( 'wp_signup_location', network_site_url( 'wp-signup.php' ) );
    535 			} else {
    536 				$redirect_url = wp_registration_url();
    537 			}
    538 
    539 			wp_redirect( $redirect_url, 301 );
    540 			die();
    541 		}
    542 	}
    543 
    544 	$redirect['query'] = preg_replace( '#^\??&*?#', '', $redirect['query'] );
    545 
    546 	// Tack on any additional query vars.
    547 	if ( $redirect_url && ! empty( $redirect['query'] ) ) {
    548 		parse_str( $redirect['query'], $_parsed_query );
    549 		$redirect = parse_url( $redirect_url );
    550 
    551 		if ( ! empty( $_parsed_query['name'] ) && ! empty( $redirect['query'] ) ) {
    552 			parse_str( $redirect['query'], $_parsed_redirect_query );
    553 
    554 			if ( empty( $_parsed_redirect_query['name'] ) ) {
    555 				unset( $_parsed_query['name'] );
    556 			}
    557 		}
    558 
    559 		$_parsed_query = array_combine(
    560 			rawurlencode_deep( array_keys( $_parsed_query ) ),
    561 			rawurlencode_deep( array_values( $_parsed_query ) )
    562 		);
    563 
    564 		$redirect_url = add_query_arg( $_parsed_query, $redirect_url );
    565 	}
    566 
    567 	if ( $redirect_url ) {
    568 		$redirect = parse_url( $redirect_url );
    569 	}
    570 
    571 	// www.example.com vs. example.com
    572 	$user_home = parse_url( home_url() );
    573 
    574 	if ( ! empty( $user_home['host'] ) ) {
    575 		$redirect['host'] = $user_home['host'];
    576 	}
    577 
    578 	if ( empty( $user_home['path'] ) ) {
    579 		$user_home['path'] = '/';
    580 	}
    581 
    582 	// Handle ports.
    583 	if ( ! empty( $user_home['port'] ) ) {
    584 		$redirect['port'] = $user_home['port'];
    585 	} else {
    586 		unset( $redirect['port'] );
    587 	}
    588 
    589 	// Trailing /index.php.
    590 	$redirect['path'] = preg_replace( '|/' . preg_quote( $wp_rewrite->index, '|' ) . '/*?$|', '/', $redirect['path'] );
    591 
    592 	$punctuation_pattern = implode(
    593 		'|',
    594 		array_map(
    595 			'preg_quote',
    596 			array(
    597 				' ',
    598 				'%20',  // Space.
    599 				'!',
    600 				'%21',  // Exclamation mark.
    601 				'"',
    602 				'%22',  // Double quote.
    603 				"'",
    604 				'%27',  // Single quote.
    605 				'(',
    606 				'%28',  // Opening bracket.
    607 				')',
    608 				'%29',  // Closing bracket.
    609 				',',
    610 				'%2C',  // Comma.
    611 				'.',
    612 				'%2E',  // Period.
    613 				';',
    614 				'%3B',  // Semicolon.
    615 				'{',
    616 				'%7B',  // Opening curly bracket.
    617 				'}',
    618 				'%7D',  // Closing curly bracket.
    619 				'%E2%80%9C', // Opening curly quote.
    620 				'%E2%80%9D', // Closing curly quote.
    621 			)
    622 		)
    623 	);
    624 
    625 	// Remove trailing spaces and end punctuation from the path.
    626 	$redirect['path'] = preg_replace( "#($punctuation_pattern)+$#", '', $redirect['path'] );
    627 
    628 	if ( ! empty( $redirect['query'] ) ) {
    629 		// Remove trailing spaces and end punctuation from certain terminating query string args.
    630 		$redirect['query'] = preg_replace( "#((^|&)(p|page_id|cat|tag)=[^&]*?)($punctuation_pattern)+$#", '$1', $redirect['query'] );
    631 
    632 		// Clean up empty query strings.
    633 		$redirect['query'] = trim( preg_replace( '#(^|&)(p|page_id|cat|tag)=?(&|$)#', '&', $redirect['query'] ), '&' );
    634 
    635 		// Redirect obsolete feeds.
    636 		$redirect['query'] = preg_replace( '#(^|&)feed=rss(&|$)#', '$1feed=rss2$2', $redirect['query'] );
    637 
    638 		// Remove redundant leading ampersands.
    639 		$redirect['query'] = preg_replace( '#^\??&*?#', '', $redirect['query'] );
    640 	}
    641 
    642 	// Strip /index.php/ when we're not using PATHINFO permalinks.
    643 	if ( ! $wp_rewrite->using_index_permalinks() ) {
    644 		$redirect['path'] = str_replace( '/' . $wp_rewrite->index . '/', '/', $redirect['path'] );
    645 	}
    646 
    647 	// Trailing slashes.
    648 	if ( is_object( $wp_rewrite ) && $wp_rewrite->using_permalinks()
    649 		&& ! is_404() && ( ! is_front_page() || is_front_page() && get_query_var( 'paged' ) > 1 )
    650 	) {
    651 		$user_ts_type = '';
    652 
    653 		if ( get_query_var( 'paged' ) > 0 ) {
    654 			$user_ts_type = 'paged';
    655 		} else {
    656 			foreach ( array( 'single', 'category', 'page', 'day', 'month', 'year', 'home' ) as $type ) {
    657 				$func = 'is_' . $type;
    658 				if ( call_user_func( $func ) ) {
    659 					$user_ts_type = $type;
    660 					break;
    661 				}
    662 			}
    663 		}
    664 
    665 		$redirect['path'] = user_trailingslashit( $redirect['path'], $user_ts_type );
    666 	} elseif ( is_front_page() ) {
    667 		$redirect['path'] = trailingslashit( $redirect['path'] );
    668 	}
    669 
    670 	// Remove trailing slash for robots.txt or sitemap requests.
    671 	if ( is_robots()
    672 		|| ! empty( get_query_var( 'sitemap' ) ) || ! empty( get_query_var( 'sitemap-stylesheet' ) )
    673 	) {
    674 		$redirect['path'] = untrailingslashit( $redirect['path'] );
    675 	}
    676 
    677 	// Strip multiple slashes out of the URL.
    678 	if ( strpos( $redirect['path'], '//' ) > -1 ) {
    679 		$redirect['path'] = preg_replace( '|/+|', '/', $redirect['path'] );
    680 	}
    681 
    682 	// Always trailing slash the Front Page URL.
    683 	if ( trailingslashit( $redirect['path'] ) === trailingslashit( $user_home['path'] ) ) {
    684 		$redirect['path'] = trailingslashit( $redirect['path'] );
    685 	}
    686 
    687 	$original_host_low = strtolower( $original['host'] );
    688 	$redirect_host_low = strtolower( $redirect['host'] );
    689 
    690 	// Ignore differences in host capitalization, as this can lead to infinite redirects.
    691 	// Only redirect no-www <=> yes-www.
    692 	if ( $original_host_low === $redirect_host_low
    693 		|| ( 'www.' . $original_host_low !== $redirect_host_low
    694 			&& 'www.' . $redirect_host_low !== $original_host_low )
    695 	) {
    696 		$redirect['host'] = $original['host'];
    697 	}
    698 
    699 	$compare_original = array( $original['host'], $original['path'] );
    700 
    701 	if ( ! empty( $original['port'] ) ) {
    702 		$compare_original[] = $original['port'];
    703 	}
    704 
    705 	if ( ! empty( $original['query'] ) ) {
    706 		$compare_original[] = $original['query'];
    707 	}
    708 
    709 	$compare_redirect = array( $redirect['host'], $redirect['path'] );
    710 
    711 	if ( ! empty( $redirect['port'] ) ) {
    712 		$compare_redirect[] = $redirect['port'];
    713 	}
    714 
    715 	if ( ! empty( $redirect['query'] ) ) {
    716 		$compare_redirect[] = $redirect['query'];
    717 	}
    718 
    719 	if ( $compare_original !== $compare_redirect ) {
    720 		$redirect_url = $redirect['scheme'] . '://' . $redirect['host'];
    721 
    722 		if ( ! empty( $redirect['port'] ) ) {
    723 			$redirect_url .= ':' . $redirect['port'];
    724 		}
    725 
    726 		$redirect_url .= $redirect['path'];
    727 
    728 		if ( ! empty( $redirect['query'] ) ) {
    729 			$redirect_url .= '?' . $redirect['query'];
    730 		}
    731 	}
    732 
    733 	if ( ! $redirect_url || $redirect_url === $requested_url ) {
    734 		return;
    735 	}
    736 
    737 	// Hex encoded octets are case-insensitive.
    738 	if ( false !== strpos( $requested_url, '%' ) ) {
    739 		if ( ! function_exists( 'lowercase_octets' ) ) {
    740 			/**
    741 			 * Converts the first hex-encoded octet match to lowercase.
    742 			 *
    743 			 * @since 3.1.0
    744 			 * @ignore
    745 			 *
    746 			 * @param array $matches Hex-encoded octet matches for the requested URL.
    747 			 * @return string Lowercased version of the first match.
    748 			 */
    749 			function lowercase_octets( $matches ) {
    750 				return strtolower( $matches[0] );
    751 			}
    752 		}
    753 
    754 		$requested_url = preg_replace_callback( '|%[a-fA-F0-9][a-fA-F0-9]|', 'lowercase_octets', $requested_url );
    755 	}
    756 
    757 	if ( $redirect_obj instanceof WP_Post ) {
    758 		$post_status_obj = get_post_status_object( get_post_status( $redirect_obj ) );
    759 		/*
    760 		 * Unset the redirect object and URL if they are not readable by the user.
    761 		 * This condition is a little confusing as the condition needs to pass if
    762 		 * the post is not readable by the user. That's why there are ! (not) conditions
    763 		 * throughout.
    764 		 */
    765 		if (
    766 			// Private post statuses only redirect if the user can read them.
    767 			! (
    768 				$post_status_obj->private &&
    769 				current_user_can( 'read_post', $redirect_obj->ID )
    770 			) &&
    771 			// For other posts, only redirect if publicly viewable.
    772 			! is_post_publicly_viewable( $redirect_obj )
    773 		) {
    774 			$redirect_obj = false;
    775 			$redirect_url = false;
    776 		}
    777 	}
    778 
    779 	/**
    780 	 * Filters the canonical redirect URL.
    781 	 *
    782 	 * Returning false to this filter will cancel the redirect.
    783 	 *
    784 	 * @since 2.3.0
    785 	 *
    786 	 * @param string $redirect_url  The redirect URL.
    787 	 * @param string $requested_url The requested URL.
    788 	 */
    789 	$redirect_url = apply_filters( 'redirect_canonical', $redirect_url, $requested_url );
    790 
    791 	// Yes, again -- in case the filter aborted the request.
    792 	if ( ! $redirect_url || strip_fragment_from_url( $redirect_url ) === strip_fragment_from_url( $requested_url ) ) {
    793 		return;
    794 	}
    795 
    796 	if ( $do_redirect ) {
    797 		// Protect against chained redirects.
    798 		if ( ! redirect_canonical( $redirect_url, false ) ) {
    799 			wp_redirect( $redirect_url, 301 );
    800 			exit;
    801 		} else {
    802 			// Debug.
    803 			// die("1: $redirect_url<br />2: " . redirect_canonical( $redirect_url, false ) );
    804 			return;
    805 		}
    806 	} else {
    807 		return $redirect_url;
    808 	}
    809 }
    810 
    811 /**
    812  * Removes arguments from a query string if they are not present in a URL
    813  * DO NOT use this in plugin code.
    814  *
    815  * @since 3.4.0
    816  * @access private
    817  *
    818  * @param string $query_string
    819  * @param array  $args_to_check
    820  * @param string $url
    821  * @return string The altered query string
    822  */
    823 function _remove_qs_args_if_not_in_url( $query_string, array $args_to_check, $url ) {
    824 	$parsed_url = parse_url( $url );
    825 
    826 	if ( ! empty( $parsed_url['query'] ) ) {
    827 		parse_str( $parsed_url['query'], $parsed_query );
    828 
    829 		foreach ( $args_to_check as $qv ) {
    830 			if ( ! isset( $parsed_query[ $qv ] ) ) {
    831 				$query_string = remove_query_arg( $qv, $query_string );
    832 			}
    833 		}
    834 	} else {
    835 		$query_string = remove_query_arg( $args_to_check, $query_string );
    836 	}
    837 
    838 	return $query_string;
    839 }
    840 
    841 /**
    842  * Strips the #fragment from a URL, if one is present.
    843  *
    844  * @since 4.4.0
    845  *
    846  * @param string $url The URL to strip.
    847  * @return string The altered URL.
    848  */
    849 function strip_fragment_from_url( $url ) {
    850 	$parsed_url = parse_url( $url );
    851 
    852 	if ( ! empty( $parsed_url['host'] ) ) {
    853 		// This mirrors code in redirect_canonical(). It does not handle every case.
    854 		$url = $parsed_url['scheme'] . '://' . $parsed_url['host'];
    855 		if ( ! empty( $parsed_url['port'] ) ) {
    856 			$url .= ':' . $parsed_url['port'];
    857 		}
    858 
    859 		if ( ! empty( $parsed_url['path'] ) ) {
    860 			$url .= $parsed_url['path'];
    861 		}
    862 
    863 		if ( ! empty( $parsed_url['query'] ) ) {
    864 			$url .= '?' . $parsed_url['query'];
    865 		}
    866 	}
    867 
    868 	return $url;
    869 }
    870 
    871 /**
    872  * Attempts to guess the correct URL for a 404 request based on query vars.
    873  *
    874  * @since 2.3.0
    875  *
    876  * @global wpdb $wpdb WordPress database abstraction object.
    877  *
    878  * @return string|false The correct URL if one is found. False on failure.
    879  */
    880 function redirect_guess_404_permalink() {
    881 	global $wpdb;
    882 
    883 	/**
    884 	 * Filters whether to attempt to guess a redirect URL for a 404 request.
    885 	 *
    886 	 * Returning a false value from the filter will disable the URL guessing
    887 	 * and return early without performing a redirect.
    888 	 *
    889 	 * @since 5.5.0
    890 	 *
    891 	 * @param bool $do_redirect_guess Whether to attempt to guess a redirect URL
    892 	 *                                for a 404 request. Default true.
    893 	 */
    894 	if ( false === apply_filters( 'do_redirect_guess_404_permalink', true ) ) {
    895 		return false;
    896 	}
    897 
    898 	/**
    899 	 * Short-circuits the redirect URL guessing for 404 requests.
    900 	 *
    901 	 * Returning a non-null value from the filter will effectively short-circuit
    902 	 * the URL guessing, returning the passed value instead.
    903 	 *
    904 	 * @since 5.5.0
    905 	 *
    906 	 * @param null|string|false $pre Whether to short-circuit guessing the redirect for a 404.
    907 	 *                               Default null to continue with the URL guessing.
    908 	 */
    909 	$pre = apply_filters( 'pre_redirect_guess_404_permalink', null );
    910 	if ( null !== $pre ) {
    911 		return $pre;
    912 	}
    913 
    914 	if ( get_query_var( 'name' ) ) {
    915 		/**
    916 		 * Filters whether to perform a strict guess for a 404 redirect.
    917 		 *
    918 		 * Returning a truthy value from the filter will redirect only exact post_name matches.
    919 		 *
    920 		 * @since 5.5.0
    921 		 *
    922 		 * @param bool $strict_guess Whether to perform a strict guess. Default false (loose guess).
    923 		 */
    924 		$strict_guess = apply_filters( 'strict_redirect_guess_404_permalink', false );
    925 
    926 		if ( $strict_guess ) {
    927 			$where = $wpdb->prepare( 'post_name = %s', get_query_var( 'name' ) );
    928 		} else {
    929 			$where = $wpdb->prepare( 'post_name LIKE %s', $wpdb->esc_like( get_query_var( 'name' ) ) . '%' );
    930 		}
    931 
    932 		// If any of post_type, year, monthnum, or day are set, use them to refine the query.
    933 		if ( get_query_var( 'post_type' ) ) {
    934 			if ( is_array( get_query_var( 'post_type' ) ) ) {
    935 				// phpcs:ignore WordPress.DB.PreparedSQLPlaceholders.UnfinishedPrepare
    936 				$where .= " AND post_type IN ('" . join( "', '", esc_sql( get_query_var( 'post_type' ) ) ) . "')";
    937 			} else {
    938 				$where .= $wpdb->prepare( ' AND post_type = %s', get_query_var( 'post_type' ) );
    939 			}
    940 		} else {
    941 			$where .= " AND post_type IN ('" . implode( "', '", get_post_types( array( 'public' => true ) ) ) . "')";
    942 		}
    943 
    944 		if ( get_query_var( 'year' ) ) {
    945 			$where .= $wpdb->prepare( ' AND YEAR(post_date) = %d', get_query_var( 'year' ) );
    946 		}
    947 		if ( get_query_var( 'monthnum' ) ) {
    948 			$where .= $wpdb->prepare( ' AND MONTH(post_date) = %d', get_query_var( 'monthnum' ) );
    949 		}
    950 		if ( get_query_var( 'day' ) ) {
    951 			$where .= $wpdb->prepare( ' AND DAYOFMONTH(post_date) = %d', get_query_var( 'day' ) );
    952 		}
    953 
    954 		// phpcs:ignore WordPress.DB.PreparedSQL.InterpolatedNotPrepared
    955 		$post_id = $wpdb->get_var( "SELECT ID FROM $wpdb->posts WHERE $where AND post_status = 'publish'" );
    956 
    957 		if ( ! $post_id ) {
    958 			return false;
    959 		}
    960 
    961 		if ( get_query_var( 'feed' ) ) {
    962 			return get_post_comments_feed_link( $post_id, get_query_var( 'feed' ) );
    963 		} elseif ( get_query_var( 'page' ) > 1 ) {
    964 			return trailingslashit( get_permalink( $post_id ) ) . user_trailingslashit( get_query_var( 'page' ), 'single_paged' );
    965 		} else {
    966 			return get_permalink( $post_id );
    967 		}
    968 	}
    969 
    970 	return false;
    971 }
    972 
    973 /**
    974  * Redirects a variety of shorthand URLs to the admin.
    975  *
    976  * If a user visits example.com/admin, they'll be redirected to /wp-admin.
    977  * Visiting /login redirects to /wp-login.php, and so on.
    978  *
    979  * @since 3.4.0
    980  *
    981  * @global WP_Rewrite $wp_rewrite WordPress rewrite component.
    982  */
    983 function wp_redirect_admin_locations() {
    984 	global $wp_rewrite;
    985 
    986 	if ( ! ( is_404() && $wp_rewrite->using_permalinks() ) ) {
    987 		return;
    988 	}
    989 
    990 	$admins = array(
    991 		home_url( 'wp-admin', 'relative' ),
    992 		home_url( 'dashboard', 'relative' ),
    993 		home_url( 'admin', 'relative' ),
    994 		site_url( 'dashboard', 'relative' ),
    995 		site_url( 'admin', 'relative' ),
    996 	);
    997 
    998 	if ( in_array( untrailingslashit( $_SERVER['REQUEST_URI'] ), $admins, true ) ) {
    999 		wp_redirect( admin_url() );
   1000 		exit;
   1001 	}
   1002 
   1003 	$logins = array(
   1004 		home_url( 'wp-login.php', 'relative' ),
   1005 		home_url( 'login', 'relative' ),
   1006 		site_url( 'login', 'relative' ),
   1007 	);
   1008 
   1009 	if ( in_array( untrailingslashit( $_SERVER['REQUEST_URI'] ), $logins, true ) ) {
   1010 		wp_redirect( wp_login_url() );
   1011 		exit;
   1012 	}
   1013 }