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22 * @file mesh/mesh_tunnel_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;
65 * Tree to reach all peers in the tunnel
67 struct MeshTunnelTree;
70 /******************************************************************************/
71 /************************* FUNCTIONS *****************************/
72 /******************************************************************************/
77 * @param length How many hops will the path have.
79 * @return A newly allocated path with a peer array of the specified length.
82 path_new (unsigned int length);
88 * @param path The path to invert.
91 path_invert (struct MeshPeerPath *path);
95 * Duplicate a path, incrementing short peer's rc.
97 * @param path The path to duplicate.
100 path_duplicate (struct MeshPeerPath *path);
104 * Get the length of a path.
106 * @param path The path to measure, with the local peer at any point of it.
108 * @return Number of hops to reach destination.
109 * UINT_MAX in case the peer is not in the path.
112 path_get_length (struct MeshPeerPath *path);
116 * Destroy the path and free any allocated resources linked to it
118 * @param p the path to destroy
120 * @return GNUNET_OK on success
123 path_destroy (struct MeshPeerPath *p);
126 /******************************************************************************/
129 * Method called whenever a node has been marked as disconnected.
131 * @param cls Closure.
132 * @param peer_id short ID of peer that is no longer reachable.
134 typedef void (*MeshTreeCallback) (void *cls, GNUNET_PEER_Id peer_id);
138 * Create a new tunnel tree associated to a tunnel
140 * @param peer A short peer id of the root of the tree
142 * @return A newly allocated and initialized tunnel tree
144 struct MeshTunnelTree *
145 tree_new (GNUNET_PEER_Id peer);
149 * Set the status of a node.
152 * @param peer A short peer id of the node.
153 * @param status New status to set.
156 tree_set_status (struct MeshTunnelTree *tree, GNUNET_PEER_Id peer,
157 enum MeshPeerState status);
161 * Get the status of a node.
163 * @param tree Tree whose local id we want to now.
164 * @param peer A short peer id of the node.
166 * @return Short peer id of local peer.
169 tree_get_status (struct MeshTunnelTree *tree, GNUNET_PEER_Id peer);
173 * Get the id of the predecessor of the local node.
175 * @param tree Tree whose local id we want to now.
177 * @return Short peer id of local peer.
180 tree_get_predecessor (struct MeshTunnelTree *tree);
184 * Find the first peer whom to send a packet to go down this path
186 * @param t The tunnel tree to use
187 * @param peer The peerinfo of the peer we are trying to reach
189 * @return peerinfo of the peer who is the first hop in the tunnel
192 struct GNUNET_PeerIdentity *
193 tree_get_first_hop (struct MeshTunnelTree *t, GNUNET_PEER_Id peer);
197 * Find the given peer in the tree.
199 * @param tree Tree where to look for the peer.
200 * @param peer_id Peer to find.
202 * @return Pointer to the node of the peer. NULL if not found.
204 struct MeshTunnelTreeNode *
205 tree_find_peer (struct MeshTunnelTree *tree, GNUNET_PEER_Id peer_id);
209 * Iterate over all children of the local node.
211 * @param tree Tree to use. Must have "me" set.
212 * @param cb Callback to call over each child.
213 * @param cls Closure.
216 tree_iterate_children (struct MeshTunnelTree *tree, MeshTreeCallback cb,
221 * Recusively update the info about what is the first hop to reach the node
223 * @param tree Tree this nodes belongs to.
224 * @param parent_id Short ID from node form which to start updating.
225 * @param hop If known, ID of the first hop.
226 * If not known, NULL to find out and pass on children.
229 tree_update_first_hops (struct MeshTunnelTree *tree, GNUNET_PEER_Id parent_id,
230 struct GNUNET_PeerIdentity *hop);
233 * Delete the current path to the peer, including all now unused relays.
234 * The destination peer is NOT destroyed, it is returned in order to either set
235 * a new path to it or destroy it explicitly, taking care of it's child nodes.
237 * @param t Tunnel tree where to delete the path from.
238 * @param peer_id Short ID of the destination peer whose path we want to remove.
239 * @param cb Callback to use to notify about which peers are going to be
241 * @param cbcls Closure for cb.
243 * @return pointer to the pathless node.
244 * NULL when not found
246 struct MeshTunnelTreeNode *
247 tree_del_path (struct MeshTunnelTree *t, GNUNET_PEER_Id peer_id,
248 MeshTreeCallback cb, void *cbcls);
252 * Return a newly allocated individual path to reach a peer from the local peer,
253 * according to the path tree of some tunnel.
255 * @param t Tunnel from which to read the path tree
256 * @param peer Destination peer to whom we want a path
258 * @return A newly allocated individual path to reach the destination peer.
259 * Path must be destroyed afterwards.
261 struct MeshPeerPath *
262 tree_get_path_to_peer (struct MeshTunnelTree *t, GNUNET_PEER_Id peer);
266 * Integrate a stand alone path into the tunnel tree.
268 * @param t Tunnel where to add the new path.
269 * @param p Path to be integrated.
270 * @param cb Callback to use to notify about peers temporarily disconnecting.
271 * @param cbcls Closure for cb.
273 * @return GNUNET_OK in case of success.
274 * GNUNET_SYSERR in case of error.
277 tree_add_path (struct MeshTunnelTree *t, const struct MeshPeerPath *p,
278 MeshTreeCallback cb, void *cbcls);
282 * Notifies a tree that a connection it might be using is broken.
283 * Marks all peers down the paths as disconnected and notifies the client.
285 * @param t Tree to use.
286 * @param p1 Short id of one of the peers (order unimportant)
287 * @param p2 Short id of one of the peers (order unimportant)
288 * @param cb Function to call for every peer that is marked as disconnected.
289 * @param cbcls Closure for cb.
291 * @return Short ID of the first disconnected peer in the tree.
294 tree_notify_connection_broken (struct MeshTunnelTree *t, GNUNET_PEER_Id p1,
295 GNUNET_PEER_Id p2, MeshTreeCallback cb,
300 * Deletes a peer from a tunnel, liberating all unused resources on the path to
301 * it. It shouldn't have children, if it has they will be destroyed as well.
302 * If the tree is not local and no longer has any paths, the root node will be
303 * destroyed and marked as NULL.
305 * @param t Tunnel tree to use.
306 * @param peer Short ID of the peer to remove from the tunnel tree.
307 * @param cb Callback to notify client of disconnected peers.
308 * @param cbcls Closure for cb.
310 * @return GNUNET_YES if the tunnel still has nodes
313 tree_del_peer (struct MeshTunnelTree *t, GNUNET_PEER_Id peer,
314 MeshTreeCallback cb, void *cbcls);
318 * Get the cost of the path relative to the already built tunnel tree
320 * @param t The tunnel tree to which compare
321 * @param path The individual path to reach a peer
323 * @return Number of hops to reach destination, UINT_MAX in case the peer is not
327 tree_get_path_cost (struct MeshTunnelTree *t, struct MeshPeerPath *path);
331 * Print the tree on stderr
336 tree_debug (struct MeshTunnelTree *t);
340 * Destroy the whole tree and free all used memory and Peer_Ids
342 * @param t Tree to be destroyed
345 tree_destroy (struct MeshTunnelTree *t);