struct FirewallConfig *insertElem (struct ConfigEntry *entry, struct FirewallConfig *tree, int *errno) {
  if (tree != NULL) {

	int r = compareEntry(entry, tree->entry);
    if (r == 0) {
      *errno = ALREADY_IN_TREE;
      return (NULL);
    }

    if (r < 0) 
      tree->left = insertElem (entry, tree->left, errno);
    else 
      tree->right = insertElem (entry, tree->right, errno);
  }
  else {
    /* create a new leaf */
    tree = malloc (sizeof (struct FirewallConfig));
    if (!tree) {
      *errno = OUT_OF_MEMORY;
      return (NULL);
    }
    
    tree->entry = entry;
    tree->left = NULL;
    tree->right = NULL;
  }
  return tree;
}

struct FirewallConfig {
  struct ConfigEntry *entry;
  struct FirewallConfig *left;
  struct FirewallConfig *right;
};


int compareEntry (struct ConfigEntry *entry1, struct ConfigEntry *entry2) {
  
  int result;
 
  result = strCompare (entry1->uid, entry2->uid);
  if (result != 0 ) {
    return result;
  }
 
  result = strCompare (entry1->program, entry2->program);
  if (result != 0 ) {
    return result;
  }
 
  result = strCompare (entry1->IPAddress, entry2->IPAddress);
  if (result != 0 ) {
    return result;
  }
 
  if (entry1->port < entry2->port) 
    return -1;
  else if (entry1->port > entry2->port) 
    return 1;
  else 
    return 0;
 
}