wp-includes/canonical.php

   1 <?php
   2 // Based on "Permalink Redirect" from Scott Yang and "Enforce www. Preference" by Mark Jaquith
   3
   4 function redirect_canonical($requested_url=NULL, $do_redirect=true) {
   5         global $wp_rewrite, $posts, $is_IIS;
   6
   7         if ( is_feed() || is_trackback() || is_search() || is_comments_popup() || is_admin() || $is_IIS || ( isset($_POST) && count($_POST) ) || is_preview() )
   8                 return;
   9
  10         if ( !$requested_url ) {
  11                 // build the URL in the address bar
  12                 $requested_url  = ( isset($_SERVER['HTTPS'] ) && strtolower($_SERVER['HTTPS']) == 'on' ) ? 'https://' : 'http://';
  13                 $requested_url .= $_SERVER['HTTP_HOST'];
  14                 $requested_url .= $_SERVER['REQUEST_URI'];
  15         }
  16
  17         $original = @parse_url($requested_url);
  18         if ( false === $original )
  19                 return;
  20
  21         // Some PHP setups turn requests for / into /index.php in REQUEST_URI
  22         $original['path'] = preg_replace('|/index\.php$|', '/', $original['path']);
  23
  24         $redirect = $original;
  25         $redirect_url = false;
  26
  27         // These tests give us a WP-generated permalink
  28         if ( is_404() ) {
  29                 $redirect_url = redirect_guess_404_permalink();
  30         } elseif ( is_object($wp_rewrite) && $wp_rewrite->using_permalinks() ) {
  31                 // rewriting of old ?p=X, ?m=2004, ?m=200401, ?m=20040101
  32                 if ( is_single() && isset($_GET['p']) ) {
  33                         if ( $redirect_url = get_permalink(get_query_var('p')) )
  34                                 $redirect['query'] = remove_query_arg('p', $redirect['query']);
  35                 } elseif ( is_page() && isset($_GET['page_id']) ) {
  36                         if ( $redirect_url = get_permalink(get_query_var('page_id')) )
  37                                 $redirect['query'] = remove_query_arg('page_id', $redirect['query']);
  38                 } elseif ( isset($_GET['m']) && ( is_year() || is_month() || is_day() ) ) {
  39                         $m = get_query_var('m');
  40                         switch ( strlen($m) ) {
  41                                 case 4: // Yearly
  42                                         $redirect_url = get_year_link($m);
  43                                         break;
  44                                 case 6: // Monthly
  45                                         $redirect_url = get_month_link( substr($m, 0, 4), substr($m, 4, 2) );
  46                                         break;
  47                                 case 8: // Daily
  48                                         $redirect_url = get_day_link(substr($m, 0, 4), substr($m, 4, 2), substr($m, 6, 2));
  49                                         break;
  50                         }
  51                         if ( $redirect_url )
  52                                 $redirect['query'] = remove_query_arg('m', $redirect['query']);
  53                 // now moving on to non ?m=X year/month/day links
  54                 } elseif ( is_day() && get_query_var('year') && get_query_var('monthnum') && isset($_GET['day']) ) {
  55                         if ( $redirect_url = get_day_link(get_query_var('year'), get_query_var('monthnum'), get_query_var('day')) )
  56                                 $redirect['query'] = remove_query_arg(array('year', 'monthnum', 'day'), $redirect['query']);
  57                 } elseif ( is_month() && get_query_var('year') && isset($_GET['monthnum']) ) {
  58                         if ( $redirect_url = get_month_link(get_query_var('year'), get_query_var('monthnum')) )
  59                                 $redirect['query'] = remove_query_arg(array('year', 'monthnum'), $redirect['query']);
  60                 } elseif ( is_year() && isset($_GET['year']) ) {
  61                         if ( $redirect_url = get_year_link(get_query_var('year')) )
  62                                 $redirect['query'] = remove_query_arg('year', $redirect['query']);
  63                 } elseif ( is_category() && isset($_GET['cat']) ) {
  64                         if ( $redirect_url = get_category_link(get_query_var('cat')) )
  65                                 $redirect['query'] = remove_query_arg('cat', $redirect['query']);
  66                 } elseif ( is_author() && isset($_GET['author']) ) {
  67                         $author = get_userdata(get_query_var('author'));
  68                         if ( false !== $author && $redirect_url = get_author_link(false, $author->ID, $author->user_nicename) )
  69                                 $redirect['query'] = remove_query_arg('author', $redirect['author']);
  70                 }
  71
  72         // paging
  73                 if ( $paged = get_query_var('paged') ) {
  74                         if ( $paged > 0 ) {
  75                                 if ( !$redirect_url )
  76                                         $redirect_url = $requested_url;
  77                                 $paged_redirect = @parse_url($redirect_url);
  78                                 $paged_redirect['path'] = preg_replace('|/page/[0-9]+?(/+)?$|', '/', $paged_redirect['path']); // strip off any existing paging
  79                                 $paged_redirect['path'] = preg_replace('|/index.php/?$|', '/', $paged_redirect['path']); // strip off trailing /index.php/
  80                                 if ( $paged > 1 && !is_single() ) {
  81                                         $paged_redirect['path'] = trailingslashit($paged_redirect['path']);
  82                                         if ( $wp_rewrite->using_index_permalinks() && strpos($paged_redirect['path'], '/index.php/') === false )
  83                                                 $paged_redirect['path'] .= 'index.php/';
  84                                         $paged_redirect['path'] .= user_trailingslashit("page/$paged", 'paged');
  85                                 } elseif ( !is_home() && !is_single() ){
  86                                         $paged_redirect['path'] = user_trailingslashit($paged_redirect['path'], 'paged');
  87                                 }
  88                                 $redirect_url = $paged_redirect['scheme'] . '://' . $paged_redirect['host'] . $paged_redirect['path'];
  89                                 $redirect['path'] = $paged_redirect['path'];
  90                         }
  91                         $redirect['query'] = remove_query_arg('paged', $redirect['query']);
  92                 }
  93         }
  94
  95         // tack on any additional query vars
  96         if ( $redirect_url && $redirect['query'] ) {
  97                 if ( strpos($redirect_url, '?') !== false )
  98                         $redirect_url .= '&';
  99                 else
 100                         $redirect_url .= '?';
 101                 $redirect_url .= $redirect['query'];
 102         }
 103
 104         if ( $redirect_url )
 105                 $redirect = @parse_url($redirect_url);
 106
 107         // www.example.com vs example.com
 108         $user_home = @parse_url(get_option('home'));
 109         $redirect['host'] = $user_home['host'];
 110
 111         // Handle ports
 112         if ( isset($user_home['port']) )
 113                 $redirect['port'] = $user_home['port'];
 114         else
 115                 unset($redirect['port']);
 116
 117         // trailing /index.php/
 118         $redirect['path'] = preg_replace('|/index.php/$|', '/', $redirect['path']);
 119
 120         // strip /index.php/ when we're not using PATHINFO permalinks
 121         if ( !$wp_rewrite->using_index_permalinks() )
 122                 $redirect['path'] = str_replace('/index.php/', '/', $redirect['path']);
 123
 124         // trailing slashes
 125         if ( is_object($wp_rewrite) && $wp_rewrite->using_permalinks() && !is_404() && (!is_home() || ( is_home() && (get_query_var('paged') > 1) ) ) ) {
 126                 $user_ts_type = '';
 127                 if ( get_query_var('paged') > 0 ) {
 128                         $user_ts_type = 'paged';
 129                 } else {
 130                         foreach ( array('single', 'category', 'page', 'day', 'month', 'year') as $type ) {
 131                                 $func = 'is_' . $type;
 132                                 if ( call_user_func($func) )
 133                                         $user_ts_type = $type;
 134                                         break;
 135                                 }
 136                         }
 137                 $redirect['path'] = user_trailingslashit($redirect['path'], $user_ts_type);
 138         } elseif ( is_home() ) {
 139                 $redirect['path'] = trailingslashit($redirect['path']);
 140         }
 141
 142         // Always trailing slash the 'home' URL
 143         if ( $redirect['path'] == $user_home['path'] )
 144                 $redirect['path'] = trailingslashit($redirect['path']);
 145
 146         // Ignore differences in host capitalization, as this can lead to infinite redirects
 147         if ( strtolower($original['host']) == strtolower($redirect['host']) )
 148                 $redirect['host'] = $original['host'];
 149
 150         if ( array($original['host'], $original['port'], $original['path'], $original['query']) !== array($redirect['host'], $redirect['port'], $redirect['path'], $redirect['query']) ) {
 151                 $redirect_url = $redirect['scheme'] . '://' . $redirect['host'];
 152                 if ( isset($redirect['port']) )
 153                         $redirect_url .= ':' . $redirect['port'];
 154                 $redirect_url .= $redirect['path'];
 155                 if ( $redirect['query'] )
 156                         $redirect_url .= '?' . $redirect['query'];
 157         }
 158
 159         if ( $redirect_url && $redirect_url != $requested_url ) {
 160                 // var_dump($redirect_url); die();
 161                 $redirect_url = apply_filters('redirect_canonical', $redirect_url, $requested_url);
 162                 if ( $do_redirect) {
 163                         // protect against chained redirects
 164                         if ( !redirect_canonical($redirect_url, false) ) {
 165                                 wp_redirect($redirect_url, 301);
 166                                 exit();
 167                         } else {
 168                                 return false;
 169                         }
 170                 } else {
 171                         return $redirect_url;
 172                 }
 173         } else {
 174                 return false;
 175         }
 176 }
 177
 178 function redirect_guess_404_permalink() {
 179         global $wp_query, $wpdb;
 180         if ( !get_query_var('name') )
 181                 return false;
 182
 183         $where = "post_name LIKE '" . $wpdb->escape(get_query_var('name')) . "%'";
 184
 185         // if any of year, monthnum, or day are set, use them to refine the query
 186         if ( get_query_var('year') )
 187                 $where .= " AND YEAR(post_date) = '" . $wpdb->escape(get_query_var('year')) . "'";
 188         if ( get_query_var('monthnum') )
 189                 $where .= " AND MONTH(post_date) = '" . $wpdb->escape(get_query_var('monthnum')) . "'";
 190         if ( get_query_var('day') )
 191                 $where .= " AND DAYOFMONTH(post_date) = '" . $wpdb->escape(get_query_var('day')) . "'";
 192
 193         $post_id = $wpdb->get_var("SELECT ID FROM $wpdb->posts WHERE $where AND post_status = 'publish'");
 194         if ( !$post_id )
 195                 return false;
 196         return get_permalink($post_id);
 197 }
 198
 199 add_action('template_redirect', 'redirect_canonical');
 200
 201 ?>