HTML Examples/WP.iso/wordpress/wp-trackback.php

PHP Script | 2017-10-23 | 4.5 KB | 147 lines

<?php
/**
 * Handle Trackbacks and Pingbacks Sent to WordPress
 *
 * @since 0.71
 *
 * @package WordPress
 * @subpackage Trackbacks
 */

if (empty($wp)) {
    require_once( dirname( __FILE__ ) . '/wp-load.php' );
    wp( array( 'tb' => '1' ) );
}

/**
 * Response to a trackback.
 *
 * Responds with an error or success XML message.
 *
 * @since 0.71
 *
 * @param mixed  $error         Whether there was an error.
 *                              Default '0'. Accepts '0' or '1', true or false.
 * @param string $error_message Error message if an error occurred.
 */
function trackback_response($error = 0, $error_message = '') {
    header('Content-Type: text/xml; charset=' . get_option('blog_charset') );
    if ($error) {
        echo '<?xml version="1.0" encoding="utf-8"?'.">\n";
        echo "<response>\n";
        echo "<error>1</error>\n";
        echo "<message>$error_message</message>\n";
        echo "</response>";
        die();
    } else {
        echo '<?xml version="1.0" encoding="utf-8"?'.">\n";
        echo "<response>\n";
        echo "<error>0</error>\n";
        echo "</response>";
    }
}

// Trackback is done by a POST.
$request_array = 'HTTP_POST_VARS';

if ( !isset($_GET['tb_id']) || !$_GET['tb_id'] ) {
    $tb_id = explode('/', $_SERVER['REQUEST_URI']);
    $tb_id = intval( $tb_id[ count($tb_id) - 1 ] );
}

$tb_url  = isset($_POST['url'])     ? $_POST['url']     : '';
$charset = isset($_POST['charset']) ? $_POST['charset'] : '';

// These three are stripslashed here so they can be properly escaped after mb_convert_encoding().
$title     = isset($_POST['title'])     ? wp_unslash($_POST['title'])      : '';
$excerpt   = isset($_POST['excerpt'])   ? wp_unslash($_POST['excerpt'])    : '';
$blog_name = isset($_POST['blog_name']) ? wp_unslash($_POST['blog_name'])  : '';

if ($charset)
    $charset = str_replace( array(',', ' '), '', strtoupper( trim($charset) ) );
else
    $charset = 'ASCII, UTF-8, ISO-8859-1, JIS, EUC-JP, SJIS';

// No valid uses for UTF-7.
if ( false !== strpos($charset, 'UTF-7') )
    die;

// For international trackbacks.
if ( function_exists('mb_convert_encoding') ) {
    $title     = mb_convert_encoding($title, get_option('blog_charset'), $charset);
    $excerpt   = mb_convert_encoding($excerpt, get_option('blog_charset'), $charset);
    $blog_name = mb_convert_encoding($blog_name, get_option('blog_charset'), $charset);
}

// Now that mb_convert_encoding() has been given a swing, we need to escape these three.
$title     = wp_slash($title);
$excerpt   = wp_slash($excerpt);
$blog_name = wp_slash($blog_name);

if ( is_single() || is_page() )
    $tb_id = $posts[0]->ID;

if ( !isset($tb_id) || !intval( $tb_id ) )
    trackback_response( 1, __( 'I really need an ID for this to work.' ) );

if (empty($title) && empty($tb_url) && empty($blog_name)) {
    // If it doesn't look like a trackback at all.
    wp_redirect(get_permalink($tb_id));
    exit;
}

if ( !empty($tb_url) && !empty($title) ) {
    /**
    * Fires before the trackback is added to a post.
    *
    * @since 4.7.0
    *
    * @param int    $tb_id     Post ID related to the trackback.
    * @param string $tb_url    Trackback URL.
    * @param string $charset   Character Set.
    * @param string $title     Trackback Title.
    * @param string $excerpt   Trackback Excerpt.
    * @param string $blog_name Blog Name.
    */
    do_action( 'pre_trackback_post', $tb_id, $tb_url, $charset, $title, $excerpt, $blog_name );

    header('Content-Type: text/xml; charset=' . get_option('blog_charset') );

    if ( !pings_open($tb_id) )
        trackback_response( 1, __( 'Sorry, trackbacks are closed for this item.' ) );

    $title =  wp_html_excerpt( $title, 250, '…' );
    $excerpt = wp_html_excerpt( $excerpt, 252, '…' );

    $comment_post_ID = (int) $tb_id;
    $comment_author = $blog_name;
    $comment_author_email = '';
    $comment_author_url = $tb_url;
    $comment_content = "<strong>$title</strong>\n\n$excerpt";
    $comment_type = 'trackback';

    $dupe = $wpdb->get_results( $wpdb->prepare("SELECT * FROM $wpdb->comments WHERE comment_post_ID = %d AND comment_author_url = %s", $comment_post_ID, $comment_author_url) );
    if ( $dupe )
        trackback_response( 1, __( 'We already have a ping from that URL for this post.' ) );

    $commentdata = compact('comment_post_ID', 'comment_author', 'comment_author_email', 'comment_author_url', 'comment_content', 'comment_type');

    $result = wp_new_comment( $commentdata );

    if ( is_wp_error( $result ) ) {
        trackback_response( 1, $result->get_error_message() );
    }

    $trackback_id = $wpdb->insert_id;

    /**
     * Fires after a trackback is added to a post.
     *
     * @since 1.2.0
     *
     * @param int $trackback_id Trackback ID.
     */
    do_action( 'trackback_post', $trackback_id );
    trackback_response( 0 );
}