Add set 0 as min length of line if negative input value.
Add return -1 to get finger size from NULL object
sd can not be NULL. Please explain in which case this patch is necessary.
as @cedric said this case is impossible
It should read "if object is invalid". But then an EAPI wrapper must be written or maybe signal to eolian that the default value is (-1).
This is a too old patch, nobody keeps tracking on this anymore.