ladspa::get_ladspa_descriptor

pub unsafe extern fn get_ladspa_descriptor(index: u64) -> Option<PluginDescriptor>

Your plugin must implement this function. get_ladspa_descriptor returns a description of a supported plugin for a given plugin index. When the index is out of bounds for the number of plugins supported by your library, you are expected to return None.

Example no-op implementation:

#[no_mangle]
pub extern fn get_ladspa_descriptor(index: u64) -> Option<ladspa::PluginDescriptor> {
    None
}