fspath() /* ... */{
			let path = env.documentroot;

			for (let i = 0; i < arguments.length; i++)
				path += `/${arguments[i]}`;

			const p = path.replace(/\/+$/, '').replace(/\/+/g, '/').split(/\//), res = [];

			for (let i = 0; i < p.length; i++)
				if (p[i] == '..')
					res.pop();
				else if (p[i] != '.')
					res.push(p[i]);

			return res.join('/');
		}
Construct an absolute filesystem path relative to the server
document root.

@instance
@memberof LuCI

@param {...string} [parts]
An array of parts to join into a path.

@return {string}
Return the joined path.