NCE *encoder_inst,
                                            void *construct_data);
 typedef void OSSL_ENCODER_CLEANUP(void *construct_data);

 int OSSL_ENCODER_CTX_set_construct(OSSL_ENCODER_CTX *ctx,
                                    OSSL_ENCODER_CONSTRUCT *construct);
 int OSSL_ENCODER_CTX_set_construct_data(OSSL_ENCODER_CTX *ctx,
                                         void *construct_data);
 int OSSL_ENCODER_CTX_set_cleanup(OSSL_ENCODER_CTX *ctx,
                                  OSSL_ENCODER_CLEA