Allow nested folder paths in WordPress Multisite with subdirectories

sunrise.php

<?php
/**
 * Allow nested folder paths in WordPress Multisite with subdirectories
 * Updated from http://maisonbisson.com/post/14052/wordpress-hacks-nested-paths-for-wpmu-blogs/ to account for latest WordPress code
 * .htaccess rules also need to be changed to:

RewriteEngine On
RewriteBase /
RewriteRule ^index\.php$ - [L]

# add a trailing slash to /wp-admin
RewriteRule ^([[_0-9a-zA-Z-]+/]*)?wp-admin$ $1wp-admin/ [R=301,L]

RewriteCond %{REQUEST_FILENAME} -f [OR]
RewriteCond %{REQUEST_FILENAME} -d
RewriteRule ^ - [L]
RewriteRule ^(.+)?/(wp-(includes|admin|content)(/.*)?) $2 [L]
RewriteRule ^([[_0-9a-zA-Z-]+/]*)?(.*\.php)$ $2 [L]
RewriteRule . index.php [L]
 */

if (defined('DOMAIN_CURRENT_SITE') && defined('PATH_CURRENT_SITE')) {
    $current_site = new stdClass();
    $current_site->id = defined('SITE_ID_CURRENT_SITE') ? SITE_ID_CURRENT_SITE : 1;
    $current_site->domain = $domain = DOMAIN_CURRENT_SITE;
    $current_site->path = $path = PATH_CURRENT_SITE;
    if (defined('BLOG_ID_CURRENT_SITE')) {
        $current_site->blog_id = BLOG_ID_CURRENT_SITE;
    } elseif (defined('BLOGID_CURRENT_SITE')) { // deprecated.
        $current_site->blog_id = BLOGID_CURRENT_SITE;
    }

    $url = parse_url($_SERVER['REQUEST_URI'], PHP_URL_PATH);

    $patharray = ( array ) explode('/', trim($url, '/'));
    $pathsearch = '';
    $blogsearch = '';

    if (count($patharray)) {
        foreach ($patharray as $pathpart) {
            $pathsearch .= '/' . $pathpart;
            $blogsearch .= $wpdb->prepare(" OR (domain = %s AND path = %s) ", $domain, $pathsearch . '/');
        }
    }

    $current_blog = $wpdb->get_row($wpdb->prepare("SELECT *, LENGTH( path ) as pathlen FROM $wpdb->blogs WHERE domain = %s AND path = '/'", $domain, $path) . $blogsearch . 'ORDER BY pathlen DESC LIMIT 1');

    $blog_id = $current_blog->blog_id;
    $public = $current_blog->public;
    $site_id = $current_blog->site_id;

    $current_site = _ss_get_current_site_name($current_site);
}

function _ss_get_current_site_name($current_site)
{
    global $wpdb;
    $current_site->site_name = wp_cache_get($current_site->id . ':current_site_name', "site-options");
    if (!$current_site->site_name) {
        $current_site->site_name = $wpdb->get_var($wpdb->prepare("SELECT meta_value FROM $wpdb->sitemeta WHERE site_id = %d AND meta_key = 'site_name'", $current_site->id));

        if ($current_site->site_name == null) {
            $current_site->site_name = ucfirst($current_site->domain);
        }

        wp_cache_set($current_site->id . ':current_site_name', $current_site->site_name, 'site-options');
    }
    return $current_site;
}