#include "defer.hpp"

#include <ROOT/RNTupleReader.hxx>

#include <cstdio>

#include <sys/mman.h>

using namespace ROOT::Experimental;

static size_t file_size(FILE *f)
{
  fseek(f, 0, SEEK_END);
  size_t res = ftell(f);
  fseek(f, 0, SEEK_SET);
  return res;  
}

int main(int argc, char **argv)
{
  if (argc < 2) {
    fprintf(stderr, "Usage: %s <ntuple_file.root>\n", argv[0]);
    return 1;
  }

  // Open and map the file
  const char *fname = argv[0];

  FILE *file = fopen(fname, "rb");
  defer { fclose(file); };

  const int fd = fileno(file);
  const size_t fsize = file_size(file);
  void *fmem = mmap(0, fsize, PROT_READ, MAP_SHARED_VALIDATE, fd, 0);
  if (!fmem) {
    fprintf(stderr, "Failed to open file %s\n", fname);
    return 1;
  }
  defer { munmap(fmem, fsize); };

  // Get the RNTuple information

  return 0;
}