some comments

spritehttpd/include/httpd-types.h

@@ -21,9 +21,15 @@ struct httpd_options;
  * CGI handler state / return value
  */
 typedef enum {
+  /// Some work was done and the CGI wants to be called again at a later time.
+  /// Splitting long-running jobs allows other requests to be handled.
   HTTPD_CGI_MORE = 0,
+  /// The CGI handled the request and is now done with it
   HTTPD_CGI_DONE = 1,
+  /// This CGI did not handle the request, fall through to following ones
   HTTPD_CGI_NOTFOUND = 2,
+  /// This is, in effect, identical to NOTFOUND, it's returned by auth functions when a fall-through is allowed.
+  /// The next route in the route list will be attempted.
   HTTPD_CGI_AUTHENTICATED = 3,
 } httpd_cgi_state;