GetFirst is a wrapper over Index.GetAll, returning the offset for the first matching indexed CID.

New constructs a new index corresponding to the given CAR index codec.

ReadCodec reads the codec of the index by decoding the first varint read from r.

ReadFrom reads index from r.

WriteTo writes the given idx into w.

CarIndexNone is a sentinel value used as a multicodec code for the index indicating no index.

ErrNotFound signals a record is not found in the index.