ZSTD_compressStream
ZSTDLIB_API size_t ZSTD_compressStream(ZSTD_CStream* zcs, ZSTD_outBuffer* output, ZSTD_inBuffer* input);
return ZSTD_compressStream(cstream, output, input);
ret = ZSTD_compressStream(data->cstream, &output, &input);