sub upload_file {
  my ($g, $q, $readpath, $writepath) = @_;

  my $rfh;
  if (!open($rfh, "<", $readpath)) {
    $g->errorpage($q, "Could not open file '$readpath': $!\n");
    return 0;
  }

  my $wfh;
  if (!open($wfh, '>', $writepath)) {
    $g->errorpage($q, "Error creating file '$writepath': $!\n");
    return 0;
  }
  
  binmode($rfh);
  binmode($wfh);

  while (read($rfh, my $buf, 4*1024)) {
    print $wfh $buf;
  }

  close($wfh);

  chmod 0600, $writepath;

  return 1;
}