RefTrieNode's are the elements of a RefTrie. Each node is associated to a Key and possibly a Payload. Nodes with a Payload ("full") can have 0, 1 or 2 children. Nodes without a Payload ("empty") can only be internal nodes, and MUST have 2 children (or they have no reason to exist).
Children have a Key which is strictly contained in their parent's Key -- more precisely, they are in either the left or the right half of the parent's Key. The branch to which a child is attached (left or right) is defined accordingly.
typedef IPNet<A> Key | Key |
typedef MiniTraits<Payload>::NonConst PPayload | PPayload |
RefTrieNode ()
| RefTrieNode |
RefTrieNode (const Key& key, const Payload& p, RefTrieNode* up = 0)
| RefTrieNode |
RefTrieNode (const Key& key, RefTrieNode* up = 0)
| RefTrieNode |
~RefTrieNode ()
| ~RefTrieNode |
RefTrieNode * insert (RefTrieNode **root,
const Key& key,
const Payload& p,
bool& replaced)
| insert |
[static]
add a node to a subtree
Returns: a pointer to the node.
RefTrieNode * erase ()
| erase |
erase current node, replumb. Returns the new root.
RefTrieNode * find (const Key& key)
| find |
main search routine. Given a key, returns a node.
const RefTrieNode * const_find (const Key& key)
| const_find |
[const]
RefTrieNode * find_subtree (const Key &key)
| find_subtree |
aux search routine. Given a key, returns a subtree contained in the key, irrespective of the presence of a payload in the node.
RefTrieNode* lower_bound (const Key &key)
| lower_bound |
Given a key, find the node with that key and a payload. If the next doesn't exist or does not have a payload, find the next node in the iterator sequence. XXX check the description.
RefTrieNode* get_left ()
| get_left |
RefTrieNode* get_right ()
| get_right |
RefTrieNode* get_parent ()
| get_parent |
bool has_payload ()
| has_payload |
[const]
bool has_active_payload ()
| has_active_payload |
[const]
const Payload & const_p ()
| const_p |
[const]
Payload & p ()
| p |
void set_payload (const Payload& p)
| set_payload |
uint32_t references ()
| references |
[const]
void incr_refcount ()
| incr_refcount |
void decr_refcount ()
| decr_refcount |
bool deleted ()
| deleted |
[const]
const Key & k ()
| k |
[const]
void print (int indent, const char *msg)
|
[const]
string str ()
| str |
[const]
void delete_subtree ()
| delete_subtree |
helper function to delete an entire subtree (including the root).
void validate (const RefTrieNode *parent)
| validate |
[const]
debugging, validates a node by checking pointers and Key invariants.
bool is_left ()
| is_left |
[const]
Returns: the leftmost node under this node
RefTrieNode * leftmost ()
| leftmost |
void find_bounds (const A& a, A &lo, A &hi)
| find_bounds |
[const]
Algorithm:
n = find(a); if we have no route (hence no default), provide a fake 0/0; set lo and hi to the boundaries of the current node. if n.is_a_leaf() we are done (results are the extremes of the entry) Otherwise: we are in an intermediate node, and a can be in positions 1..5 if the node has 2 children, or 1'..3' if it has 1 child. n: |---------------.----------------| a: 1 2 3 4 5 |--X--| |--Y--| a: 1' 2' 3' |--X--| Behaviour is the following: case 1 and 1': lo already set, hi = (lowest address in X)-1 case 2 and 2': set n = X and repeat case 3: lo = (highest addr in X)+1, hi = (lowest addr in Y)-1 case 3': lo = (highest addr in X)+1, hi is already set case 4: set n = Y and repeat case 5: lo = (highest addr in Y)+1, hi is already set
Returns: the boundaries ("lo" and "hi") of the largest range that contains 'a' and maps to the same route entry.
A low ()
| low |
[const]
Returns: the lowest address in a subtree which has a route. Search starting from left or right until a full node is found.
A high ()
| high |
[const]
Returns: the highest address in a subtree which has a route. Search starting from right or left until a full node is found.