| 2905 | /** |
| 2906 | * Sanitize space or carriage return separated urls that are used to send trackbacks. |
| 2907 | * |
| 2908 | * @since 3.2.0 |
| 2909 | * |
| 2910 | * @param string $to_ping Space or carriage return separated urls |
| 2911 | * @return string Urls starting with the http or https protocol, separated by a carriage return. |
| 2912 | */ |
| 2913 | function sanitize_trackback_urls( $to_ping ) { |
| 2914 | $urls_to_ping = preg_split('/\s|\n/', $to_ping, -1, PREG_SPLIT_NO_EMPTY); |
| 2915 | foreach( $urls_to_ping as $k => $url ) { |
| 2916 | if ( !preg_match('#^https?://.#i', $url) ) |
| 2917 | unset($urls_to_ping[$k]); |
| 2918 | } |
| 2919 | $sani_to_ping = implode( "\n", $urls_to_ping ); |
| 2920 | return apply_filters( 'sanitize_trackback_urls', $sani_to_ping, $to_ping ); |
| 2921 | } |
| 2922 | |