root/tags/2.3.1/wp-includes/bookmark.php

<?php

function get_bookmark($bookmark_id, $output = OBJECT, $filter = 'raw') {
    global $wpdb;

    $bookmark_id = (int) $bookmark_id;
    $link = $wpdb->get_row("SELECT * FROM $wpdb->links WHERE link_id = '$bookmark_id' LIMIT 1");
    $link->link_category = array_unique( wp_get_object_terms($link_id, 'link_category', 'fields=ids') );

    $link = sanitize_bookmark($link, $filter);

    if ( $output == OBJECT ) {
        return $link;
    } elseif ( $output == ARRAY_A ) {
        return get_object_vars($link);
    } elseif ( $output == ARRAY_N ) {
        return array_values(get_object_vars($link));
    } else {
        return $link;
    }
}

function get_bookmark_field( $field, $bookmark, $context = 'display' ) {
    $bookmark = (int) $bookmark;
    $bookmark = get_bookmark( $bookmark );

    if ( is_wp_error($bookmark) )
        return $bookmark;

    if ( !is_object($bookmark) )
        return '';

    if ( !isset($bookmark->$field) )
        return '';

    return sanitize_bookmark_field($field, $bookmark->$field, $bookmark->link_id, $context);
}

// Deprecate
function get_link($bookmark_id, $output = OBJECT) {
    return get_bookmark($bookmark_id, $output);
}

function get_bookmarks($args = '') {
    global $wpdb;

    $defaults = array(
        'orderby' => 'name', 'order' => 'ASC',
        'limit' => -1, 'category' => '',
        'category_name' => '', 'hide_invisible' => 1,
        'show_updated' => 0, 'include' => '',
        'exclude' => ''
    );

    $r = wp_parse_args( $args, $defaults );
    extract( $r, EXTR_SKIP );

    $key = md5( serialize( $r ) );
    if ( $cache = wp_cache_get( 'get_bookmarks', 'bookmark' ) )
        if ( isset( $cache[ $key ] ) )
            return apply_filters('get_bookmarks', $cache[ $key ], $r );

    $inclusions = '';
    if ( !empty($include) ) {
    $exclude = '';  //ignore exclude, category, and category_name params if using include
    $category = '';
    $category_name = '';
        $inclinks = preg_split('/[\s,]+/',$include);
        if ( count($inclinks) ) {
            foreach ( $inclinks as $inclink ) {
                if (empty($inclusions))
                    $inclusions = ' AND ( link_id = ' . intval($inclink) . ' ';
                else
                    $inclusions .= ' OR link_id = ' . intval($inclink) . ' ';
            }
        }
    }
    if (!empty($inclusions))
        $inclusions .= ')';

    $exclusions = '';
    if ( !empty($exclude) ) {
        $exlinks = preg_split('/[\s,]+/',$exclude);
        if ( count($exlinks) ) {
            foreach ( $exlinks as $exlink ) {
                if (empty($exclusions))
                    $exclusions = ' AND ( link_id <> ' . intval($exlink) . ' ';
                else
                    $exclusions .= ' AND link_id <> ' . intval($exlink) . ' ';
            }
        }
    }
    if (!empty($exclusions))
        $exclusions .= ')';

    if ( ! empty($category_name) ) {
        if ( $category = get_term_by('name', $category_name, 'link_category') )
            $category = $category->term_id;
    }

    $category_query = '';
    $join = '';
    if ( !empty($category) ) {
        $incategories = preg_split('/[\s,]+/',$category);
        if ( count($incategories) ) {
            foreach ( $incategories as $incat ) {
                if (empty($category_query))
                    $category_query = ' AND ( tt.term_id = ' . intval($incat) . ' ';
                else
                    $category_query .= ' OR tt.term_id = ' . intval($incat) . ' ';
            }
        }
    }
    if (!empty($category_query)) {
        $category_query .= ") AND taxonomy = 'link_category'";
        $join = " INNER JOIN $wpdb->term_relationships AS tr ON ($wpdb->links.link_id = tr.object_id) INNER JOIN $wpdb->term_taxonomy as tt ON tt.term_taxonomy_id = tr.term_taxonomy_id";
    }

    if (get_option('links_recently_updated_time')) {
        $recently_updated_test = ", IF (DATE_ADD(link_updated, INTERVAL " . get_option('links_recently_updated_time') . " MINUTE) >= NOW(), 1,0) as recently_updated ";
    } else {
        $recently_updated_test = '';
    }

    if ($show_updated) {
        $get_updated = ", UNIX_TIMESTAMP(link_updated) AS link_updated_f ";
    }

    $orderby = strtolower($orderby);
    $length = '';
    switch ($orderby) {
        case 'length':
            $length = ", CHAR_LENGTH(link_name) AS length";
            break;
        case 'rand':
            $orderby = 'rand()';
            break;
        default:
            $orderby = "link_" . $orderby;
    }

    if ( 'link_id' == $orderby )
        $orderby = "$wpdb->links.link_id";

    $visible = '';
    if ( $hide_invisible )
        $visible = "AND link_visible = 'Y'";

    $query = "SELECT * $length $recently_updated_test $get_updated FROM $wpdb->links $join WHERE 1=1 $visible $category_query";
    $query .= " $exclusions $inclusions";
    $query .= " ORDER BY $orderby $order";
    if ($limit != -1)
        $query .= " LIMIT $limit";

    $results = $wpdb->get_results($query);

    $cache[ $key ] = $results;
    wp_cache_set( 'get_bookmarks', $cache, 'bookmark' );

    return apply_filters('get_bookmarks', $results, $r);
}

function sanitize_bookmark($bookmark, $context = 'display') {
    $fields = array('link_id', 'link_url', 'link_name', 'link_image', 'link_target', 'link_category',
        'link_description', 'link_visible', 'link_owner', 'link_rating', 'link_updated',
        'link_rel', 'link_notes', 'link_rss', );

    $do_object = false;
    if ( is_object($bookmark) )
        $do_object = true;

    foreach ( $fields as $field ) {
        if ( $do_object )
            $bookmark->$field = sanitize_bookmark_field($field, $bookmark->$field, $bookmark->link_id, $context);
        else
            $bookmark[$field] = sanitize_bookmark_field($field, $bookmark[$field], $bookmark['link_id'], $context);
    }

    return $bookmark;
}

function sanitize_bookmark_field($field, $value, $bookmark_id, $context) {
    $int_fields = array('link_id', 'link_rating');
    if ( in_array($field, $int_fields) )
        $value = (int) $value;

    $yesno = array('link_visible');
    if ( in_array($field, $yesno) )
        $value = preg_replace('/[^YNyn]/', '', $value);

    if ( 'link_target' == $field ) {
        $targets = array('_top', '_blank');
        if ( ! in_array($value, $targets) )
            $value = '';
    }

    if ( 'raw' == $context )
        return $value;

    if ( 'edit' == $context ) {
        $format_to_edit = array('link_notes');
        $value = apply_filters("edit_$field", $value, $bookmark_id);

        if ( in_array($field, $format_to_edit) ) {
            $value = format_to_edit($value);
        } else {
            $value = attribute_escape($value);
        }
    } else if ( 'db' == $context ) {
        $value = apply_filters("pre_$field", $value);
    } else {
        // Use display filters by default.
        $value = apply_filters($field, $value, $bookmark_id, $context);
    }

    if ( 'attribute' == $context )
        $value = attribute_escape($value);
    else if ( 'js' == $context )
        $value = js_escape($value);

    return $value;
}

function delete_get_bookmark_cache() {
    wp_cache_delete( 'get_bookmarks', 'bookmark' );
}
add_action( 'add_link', 'delete_get_bookmark_cache' );
add_action( 'edit_link', 'delete_get_bookmark_cache' );
add_action( 'delete_link', 'delete_get_bookmark_cache' );

?>