Struct lv2_raw::urid::LV2UridMap [−] [src]

#[repr(C)]
pub struct LV2UridMap {
    pub handle: LV2UridMapHandle,
    pub map: extern "C" fn(_: LV2UridMapHandle, _: *const c_char) -> LV2Urid,
}

URID Map Feature (LV2_URID__map)

Fields

handle: LV2UridMapHandle

Opaque pointer to host data.

This MUST be passed to map_uri() whenever it is called. Otherwise, it must not be interpreted in any way.

map: extern "C" fn(_: LV2UridMapHandle, _: *const c_char) -> LV2Urid

Get the numeric ID of a URI.

If the ID does not already exist, it will be created.

This function is referentially transparent; any number of calls with the same arguments is guaranteed to return the same value over the life of a plugin instance. Note, however, that several URIs MAY resolve to the same ID if the host considers those URIs equivalent.

This function is not necessarily very fast or RT-safe: plugins SHOULD cache any IDs they might need in performance critical situations.

The return value 0 is reserved and indicates that an ID for that URI could not be created for whatever reason. However, hosts SHOULD NOT return 0 from this function in non-exceptional circumstances (i.e. the URI map SHOULD be dynamic).

@param handle Must be the callback_data member of this struct. @param uri The URI to be mapped to an integer ID.