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3 (C) 2001 - 2011 Christian Grothoff (and other contributing authors)
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13 General Public License for more details.
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22 * @file mesh/mesh_tree_tree.h
23 * @brief Tunnel tree handling functions
24 * @author Bartlomiej Polot
29 /******************************************************************************/
30 /************************ DATA STRUCTURES ****************************/
31 /******************************************************************************/
34 * Information regarding a possible path to reach a single peer
42 struct MeshPeerPath *next;
43 struct MeshPeerPath *prev;
46 * List of all the peers that form the path from origin to target.
48 GNUNET_PEER_Id *peers;
51 * Number of peers (hops) in the path
59 * Node of path tree for a tunnel
61 struct MeshTunnelTreeNode
64 * Tunnel this node belongs to (and therefore tree)
69 * Peer this node describes
74 * Parent node in the tree
76 struct MeshTunnelTreeNode *parent;
81 struct MeshTunnelTreeNode *next;
86 struct MeshTunnelTreeNode *prev;
91 struct MeshTunnelTreeNode *children_head;
96 struct MeshTunnelTreeNode *children_tail;
99 * Status of the peer in the tunnel
101 enum MeshPeerState status;
106 * Tree to reach all peers in the tunnel
108 struct MeshTunnelTree
111 * How often to refresh the path
113 struct GNUNET_TIME_Relative refresh;
116 * Tunnel this path belongs to
118 struct MeshTunnel *t;
121 * Root node of peer tree
123 struct MeshTunnelTreeNode *root;
126 * Node that represents our position in the tree (for non local tunnels)
128 struct MeshTunnelTreeNode *me;
131 * Cache of all peers and the first hop to them.
132 * Indexed by PeerIdentity, contains a pointer to the PeerIdentity
135 struct GNUNET_CONTAINER_MultiHashMap *first_hops;
140 /******************************************************************************/
141 /************************* FUNCTIONS *****************************/
142 /******************************************************************************/
146 * Method called whenever a node has been marked as disconnected.
148 * @param node peer identity the tunnel stopped working with
150 typedef void (*MeshNodeDisconnectCB) (const struct MeshTunnelTreeNode * node);
156 * @param p the path to invert
159 path_invert (struct MeshPeerPath *path);
164 * Destroy the path and free any allocated resources linked to it
166 * @param p the path to destroy
168 * @return GNUNET_OK on success
171 path_destroy (struct MeshPeerPath *p);
175 * Find the first peer whom to send a packet to go down this path
177 * @param t The tunnel to use
178 * @param peer The peerinfo of the peer we are trying to reach
180 * @return peerinfo of the peer who is the first hop in the tunnel
183 struct GNUNET_PeerIdentity *
184 path_get_first_hop (struct MeshTunnelTree *t, GNUNET_PEER_Id peer);
188 * Get the length of a path
190 * @param path The path to measure, with the local peer at any point of it
192 * @return Number of hops to reach destination
193 * UINT_MAX in case the peer is not in the path
196 path_get_length (struct MeshPeerPath *path);
200 * Get the cost of the path relative to the already built tunnel tree
202 * @param t The tunnel tree to which compare
203 * @param path The individual path to reach a peer
205 * @return Number of hops to reach destination, UINT_MAX in case the peer is not
209 path_get_cost (struct MeshTunnelTree *t, struct MeshPeerPath *path);
213 * Recursively find the given peer in the tree.
215 * @param t Tunnel where to look for the peer.
216 * @param peer Peer to find
218 * @return Pointer to the node of the peer. NULL if not found.
220 struct MeshTunnelTreeNode *
221 tree_find_peer (struct MeshTunnelTreeNode *root, GNUNET_PEER_Id peer_id);
225 * Delete the current path to the peer, including all now unused relays.
226 * The destination peer is NOT destroyed, it is returned in order to either set
227 * a new path to it or destroy it explicitly, taking care of it's child nodes.
229 * @param t Tunnel where to delete the path from.
230 * @param peer Destination peer whose path we want to remove.
231 * @param cb Callback to use to notify about disconnected peers
233 * @return pointer to the pathless node, NULL on error
235 struct MeshTunnelTreeNode *
236 tree_del_path (struct MeshTunnelTree *t, GNUNET_PEER_Id peer_id,
237 MeshNodeDisconnectCB cb);
241 * Return a newly allocated individual path to reach a peer from the local peer,
242 * according to the path tree of some tunnel.
244 * @param t Tunnel from which to read the path tree
245 * @param peer_info Destination peer to whom we want a path
247 * @return A newly allocated individual path to reach the destination peer.
248 * Path must be destroyed afterwards.
250 struct MeshPeerPath *
251 tree_get_path_to_peer(struct MeshTunnelTree *t, GNUNET_PEER_Id peer);
255 * Integrate a stand alone path into the tunnel tree.
257 * @param t Tunnel where to add the new path.
258 * @param p Path to be integrated.
259 * @param cb Callback to use to notify about peers temporarily disconnecting
261 * @return GNUNET_OK in case of success.
262 * GNUNET_SYSERR in case of error.
265 tree_add_path (struct MeshTunnelTree *t, const struct MeshPeerPath *p,
266 MeshNodeDisconnectCB cb);
270 * Allocates and initializes a new node.
271 * Sets ID and parent of the new node and inserts it in the DLL of the parent
273 * @param parent Node that will be the parent from the new node, NULL for root
274 * @param id Short Id of the new node
276 * @return Newly allocated node
278 struct MeshTunnelTreeNode *
279 tree_node_new(struct MeshTunnelTreeNode *parent, GNUNET_PEER_Id id);
283 * Destroy the node and all children
285 * @param n Parent node to be destroyed
288 tree_node_destroy (struct MeshTunnelTreeNode *n);
292 * Destroy the whole tree and free all used memory and Peer_Ids
294 * @param t Tree to be destroyed
297 tree_destroy (struct MeshTunnelTree *t);
301 tree_debug(struct MeshTunnelTree *t);