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.