WordPress/wp-includes/feed.php

<?php

function get_bloginfo_rss($show = '') {
	$info = strip_tags(get_bloginfo($show));
	return apply_filters('get_bloginfo_rss', convert_chars($info));
}


function bloginfo_rss($show = '') {
	echo apply_filters('bloginfo_rss', get_bloginfo_rss($show));
}

function get_wp_title_rss($sep = '&#187;') {
	$title = wp_title($sep, false);
	$title = apply_filters('get_wp_title_rss', $title);
	return $title;
}

function wp_title_rss($sep = '&#187;') {
	echo apply_filters('wp_title_rss', get_wp_title_rss($sep));
}

function get_the_title_rss() {
	$title = get_the_title();
	$title = apply_filters('the_title_rss', $title);
	return $title;
}


function the_title_rss() {
	echo get_the_title_rss();
}


function the_content_rss($more_link_text='(more...)', $stripteaser=0, $more_file='', $cut = 0, $encode_html = 0) {
	$content = get_the_content($more_link_text, $stripteaser, $more_file);
	$content = apply_filters('the_content_rss', $content);
	if ( $cut && !$encode_html )
		$encode_html = 2;
	if ( 1== $encode_html ) {
		$content = wp_specialchars($content);
		$cut = 0;
	} elseif ( 0 == $encode_html ) {
		$content = make_url_footnote($content);
	} elseif ( 2 == $encode_html ) {
		$content = strip_tags($content);
	}
	if ( $cut ) {
		$blah = explode(' ', $content);
		if ( count($blah) > $cut ) {
			$k = $cut;
			$use_dotdotdot = 1;
		} else {
			$k = count($blah);
			$use_dotdotdot = 0;
		}
		for ( $i=0; $i<$k; $i++ )
			$excerpt .= $blah[$i].' ';
		$excerpt .= ($use_dotdotdot) ? '...' : '';
		$content = $excerpt;
	}
	$content = str_replace(']]>', ']]&gt;', $content);
	echo $content;
}


function the_excerpt_rss() {
	$output = get_the_excerpt(true);
	echo apply_filters('the_excerpt_rss', $output);
}

function the_permalink_rss() {
	echo apply_filters('the_permalink_rss', get_permalink());

}

function comment_link() {
	echo get_comment_link();
}


function get_comment_author_rss() {
	return apply_filters('comment_author_rss', get_comment_author() );
}


function comment_author_rss() {
	echo get_comment_author_rss();
}


function comment_text_rss() {
	$comment_text = get_comment_text();
	$comment_text = apply_filters('comment_text_rss', $comment_text);
	echo $comment_text;
}


function comments_rss_link($link_text = 'Comments RSS', $commentsrssfilename = 'nolongerused') {
	$url = get_post_comments_feed_link();
	echo "<a href='$url'>$link_text</a>";
}


function comments_rss($commentsrssfilename = 'nolongerused') {
	return get_post_comments_feed_link();
}


function get_author_rss_link($echo = false, $author_id, $author_nicename) {
	$auth_ID = (int) $author_id;
	$permalink_structure = get_option('permalink_structure');

	if ( '' == $permalink_structure ) {
		$link = get_option('home') . '?feed=rss2&amp;author=' . $author_id;
	} else {
		$link = get_author_posts_url($author_id, $author_nicename);
		$link = $link . user_trailingslashit('feed', 'feed');
	}

	$link = apply_filters('author_feed_link', $link);

	if ( $echo )
		echo $link;
	return $link;
}


function get_category_rss_link($echo = false, $cat_ID, $category_nicename) {
	$permalink_structure = get_option('permalink_structure');

	if ( '' == $permalink_structure ) {
		$link = get_option('home') . '?feed=rss2&amp;cat=' . $cat_ID;
	} else {
		$link = get_category_link($cat_ID);
		$link = $link . user_trailingslashit('feed', 'feed');
	}

	$link = apply_filters('category_feed_link', $link);

	if ( $echo )
		echo $link;
	return $link;
}


function get_the_category_rss($type = 'rss') {
	$categories = get_the_category();
	$tags = get_the_tags();
	$home = get_bloginfo_rss('home');
	$the_list = '';
	$cat_names = array();

	$filter = 'rss';
	if ( 'atom' == $type )
		$filter = 'raw';

	if ( !empty($categories) ) foreach ( (array) $categories as $category ) {
		$cat_names[] = sanitize_term_field('name', $category->name, $category->term_id, 'category', $filter);		
	}

	if ( !empty($tags) ) foreach ( (array) $tags as $tag ) {
		$cat_names[] = sanitize_term_field('name', $tag->name, $tag->term_id, 'post_tag', $filter);		
	}

	$cat_names = array_unique($cat_names);

	foreach ( $cat_names as $cat_name ) {
		if ( 'rdf' == $type )
			$the_list .= "\n\t\t<dc:subject><![CDATA[$cat_name]]></dc:subject>\n";
		if ( 'atom' == $type )
			$the_list .= sprintf( '<category scheme="%1$s" term="%2$s" />', attribute_escape( apply_filters( 'get_bloginfo_rss', get_bloginfo( 'url' ) ) ), attribute_escape( $cat_name ) );
		else
			$the_list .= "\n\t\t<category><![CDATA[$cat_name]]></category>\n";
	}

	return apply_filters('the_category_rss', $the_list, $type);
}


function the_category_rss($type = 'rss') {
	echo get_the_category_rss($type);
}

function html_type_rss() {
	$type = get_bloginfo('html_type');
	if (strpos($type, 'xhtml') !== false)
		$type = 'xhtml';
	else
		$type = 'html';
	echo $type;
}


function rss_enclosure() {
	global $id, $post;
	if ( !empty($post->post_password) && ($_COOKIE['wp-postpass_'.COOKIEHASH] != $post->post_password) )
		return;

	foreach (get_post_custom() as $key => $val) {
		if ($key == 'enclosure') {
			foreach ((array)$val as $enc) {
				$enclosure = split("\n", $enc);
				echo apply_filters('rss_enclosure', '<enclosure url="' . trim(htmlspecialchars($enclosure[0])) . '" length="' . trim($enclosure[1]) . '" type="' . trim($enclosure[2]) . '" />' . "\n");
			}
		}
	}
}

function atom_enclosure() {
	global $id, $post;
	if ( !empty($post->post_password) && ($_COOKIE['wp-postpass_'.COOKIEHASH] != $post->post_password) )
		return;

	foreach (get_post_custom() as $key => $val) {
		if ($key == 'enclosure') {
			foreach ((array)$val as $enc) {
				$enclosure = split("\n", $enc);
				echo apply_filters('atom_enclosure', '<link href="' . trim(htmlspecialchars($enclosure[0])) . '" rel="enclosure" length="' . trim($enclosure[1]) . '" type="' . trim($enclosure[2]) . '" />' . "\n");
			}
		}
	}
}

?>