Parsed: 127538

<?php

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

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

// Always run as an unauthenticated user.
wp_set_current_user( 0 );

/* function trackback_response() – Response to a trackback. */

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

$trackback_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() ) {
  $post_id = $posts[0]->ID;
}

if ( ! isset( $post_id ) || ! (int) $post_id ) {
  trackback_response( 1, __( 'I really need an ID for this to work.' ) );
}

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

if ( ! empty( $trackback_url ) && ! empty( $title ) ) {
  
/**
 * Fires before the trackback is added to a post.
 *
 * @since 4.7.0
 *
 * @param int    $post_id       Post ID related to the trackback.
 * @param string $trackback_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', $post_id, $trackback_url, $charset, $title, $excerpt, $blog_name );

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

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

  $title   = wp_html_excerpt( $title, 250, '&#8230;' );
  $excerpt = wp_html_excerpt( $excerpt, 252, '&#8230;' );

  $comment_post_id      = (int) $post_id;
  $comment_author       = $blog_name;
  $comment_author_email = '';
  $comment_author_url   = $trackback_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, __( 'There is already a ping from that URL for this post.' ) );
  }

  $commentdata = array(
    'comment_post_ID' => $comment_post_id,
  );

  $commentdata += compact(
    '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 );
}