rntviewer/src/rntuple.cpp

internal
String8 rntuple_description(Arena *arena, const RNTuple_Info &ntuple)
{
  String8 desc = push_str8f(arena, "version %u.%u.%u.%u", 
                            ntuple.version.epoch,
                            ntuple.version.major,
                            ntuple.version.minor,
                            ntuple.version.patch);
  return desc;
}

internal
RNTuple_Info get_rntuple_info(const char *fname, const char *ntpl_name)
{
  RNTuple_Info info = {};
  
  // TODO: proper error handling
  root::RMicroFileReader file_reader { fname };
  root::RNTuple_File_Info file_info = file_reader.GetNTupleProper(ntpl_name);
  if (!file_info.failed) {
    info.version.epoch = file_info.anchor.fVersionEpoch;
    info.version.major = file_info.anchor.fVersionMajor;
    info.version.minor = file_info.anchor.fVersionMinor;
    info.version.patch = file_info.anchor.fVersionPatch;
    info.rng_header.start = file_info.anchor.fSeekHeader;
    info.rng_header.len = file_info.anchor.fNBytesHeader;
    info.rng_footer.start = file_info.anchor.fSeekFooter;
    info.rng_footer.len = file_info.anchor.fNBytesFooter;
    info.rng_anchor.start = file_info.anchor_seek;
    info.rng_anchor.len = file_info.anchor_nbytes;
    info.rng_anchor_key.start = file_info.anchor_key_seek;
    info.rng_anchor_key.len = file_info.anchor_key_nbytes;
    info.rblob_header_size = file_info.rblob_key_header_nbytes;
    info.root_file_header_size = file_info.tfile_header_nbytes;
  }

  return info;
}