show_tree(tree_t *t,                    /* I - Parent node */
          int    indent)                /* I - Indentation */
{
  while (t)
  {
    if (t->markup == MARKUP_NONE)
      printf("%*s\"%s\"\n", indent, "", t->data);
    else
      printf("%*s%s\n", indent, "", _htmlMarkups[t->markup]);

    if (t->child)
      show_tree(t->child, indent + 2);

    t = t->next;
  }
}
The software writes data past the end, or before the beginning, of the intended buffer.