analogsrc = zip_source_buffer(archive, chunkbuf, chunksize, FALSE);
chunkname = g_strdup_printf("%s-%u", basename, next_chunk_num);
i = zip_add(archive, chunkname, analogsrc);
analogsrc = zip_source_buffer(archive, chunkbuf, chunksize, FALSE);
chunkname = g_strdup_printf("%s-%u", basename, next_chunk_num);
i = zip_add(archive, chunkname, analogsrc);