ZSTD_DCtx_refDDict
ZSTDLIB_API size_t ZSTD_DCtx_refDDict(ZSTD_DCtx* dctx, const ZSTD_DDict* ddict);
FORWARD_IF_ERROR(ZSTD_DCtx_refDDict(zds, NULL), "");
FORWARD_IF_ERROR( ZSTD_DCtx_refDDict(dctx, ddict) , "");