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22 * @file mesh/mesh_tunnel_tree.c
23 * @brief Tunnel tree handling functions
24 * @author Bartlomiej Polot
28 #include "mesh_tunnel_tree.h"
30 #define MESH_TREE_DEBUG GNUNET_YES
34 * Node of path tree for a tunnel
36 struct MeshTunnelTreeNode
39 * Peer this node describes
44 * Parent node in the tree
46 struct MeshTunnelTreeNode *parent;
51 struct MeshTunnelTreeNode *next;
56 struct MeshTunnelTreeNode *prev;
61 struct MeshTunnelTreeNode *children_head;
66 struct MeshTunnelTreeNode *children_tail;
69 * Status of the peer in the tunnel
71 enum MeshPeerState status;
76 * Tree to reach all peers in the tunnel
81 * Root node of peer tree
83 struct MeshTunnelTreeNode *root;
86 * Node that represents our position in the tree (for non local tunnels)
88 struct MeshTunnelTreeNode *me;
91 * DLL of disconneted nodes
93 struct MeshTunnelTreeNode *disconnected_head;
96 * DLL of disconneted nodes
98 struct MeshTunnelTreeNode *disconnected_tail;
101 * Cache of all peers and the first hop to them.
102 * Indexed by PeerIdentity, contains a pointer to the PeerIdentity
105 struct GNUNET_CONTAINER_MultiHashMap *first_hops;
113 * @param length How many hops will the path have.
115 * @return A newly allocated path with a peer array of the specified length.
117 struct MeshPeerPath *
118 path_new (unsigned int length)
120 struct MeshPeerPath *p;
122 p = GNUNET_malloc (sizeof (struct MeshPeerPath));
126 p->peers = GNUNET_malloc (length * sizeof (GNUNET_PEER_Id));
135 * @param path the path to invert
138 path_invert (struct MeshPeerPath *path)
143 for (i = 0; i < path->length / 2; i++)
145 aux = path->peers[i];
146 path->peers[i] = path->peers[path->length - i - 1];
147 path->peers[path->length - i - 1] = aux;
153 * Duplicate a path, incrementing short peer's rc.
155 * @param path The path to duplicate.
157 struct MeshPeerPath *
158 path_duplicate (struct MeshPeerPath *path)
160 struct MeshPeerPath *aux;
163 aux = path_new (path->length);
164 memcpy (aux->peers, path->peers, path->length * sizeof (GNUNET_PEER_Id));
165 for (i = 0; i < path->length; i++)
166 GNUNET_PEER_change_rc (path->peers[i], 1);
172 * Recusively update the info about what is the first hop to reach the node
174 * @param tree Tree this nodes belongs to.
175 * @param parent The node form which to start updating.
176 * @param hop If known, ID of the first hop.
177 * If not known, NULL to find out and pass on children.
180 tree_node_update_first_hops (struct MeshTunnelTree *tree,
181 struct MeshTunnelTreeNode *parent,
182 struct GNUNET_PeerIdentity *hop);
186 * Get the length of a path.
188 * @param path The path to measure, with the local peer at any point of it.
190 * @return Number of hops to reach destination.
191 * UINT_MAX in case the peer is not in the path.
194 path_get_length (struct MeshPeerPath *path)
203 * Destroy the path and free any allocated resources linked to it
205 * @param p the path to destroy
207 * @return GNUNET_OK on success
210 path_destroy (struct MeshPeerPath *p)
214 GNUNET_PEER_decrement_rcs (p->peers, p->length);
215 GNUNET_free_non_null (p->peers);
223 * Allocates and initializes a new node.
224 * Sets ID and parent of the new node and inserts it in the DLL of the parent
226 * @param parent Node that will be the parent from the new node, NULL for root
227 * @param peer Short Id of the new node
229 * @return Newly allocated node
231 static struct MeshTunnelTreeNode *
232 tree_node_new (struct MeshTunnelTreeNode *parent, GNUNET_PEER_Id peer)
234 struct MeshTunnelTreeNode *node;
236 node = GNUNET_malloc (sizeof (struct MeshTunnelTreeNode));
238 GNUNET_PEER_change_rc (peer, 1);
239 node->parent = parent;
241 GNUNET_CONTAINER_DLL_insert (parent->children_head, parent->children_tail,
249 * Recursively find the given peer.
251 * @param parent Node where to start looking.
252 * @param peer_id Short ID of the peer to find.
254 * @return Pointer to the node of the peer. NULL if not found.
256 static struct MeshTunnelTreeNode *
257 tree_node_find_peer (struct MeshTunnelTreeNode *parent, GNUNET_PEER_Id peer_id)
259 struct MeshTunnelTreeNode *n;
260 struct MeshTunnelTreeNode *r;
262 if (parent->peer == peer_id)
264 for (n = parent->children_head; NULL != n; n = n->next)
266 r = tree_node_find_peer (n, peer_id);
275 * Recusively update the info about what is the first hop to reach the node
277 * @param tree Tree this nodes belongs to.
278 * @param parent ID from node form which to start updating.
279 * @param hop If known, ID of the first hop.
280 * If not known, NULL to find out and pass on children.
283 tree_node_update_first_hops (struct MeshTunnelTree *tree,
284 struct MeshTunnelTreeNode *parent,
285 struct GNUNET_PeerIdentity *hop)
287 struct GNUNET_PeerIdentity pi;
288 struct GNUNET_PeerIdentity *copy;
289 struct GNUNET_PeerIdentity id;
290 struct MeshTunnelTreeNode *n;
293 GNUNET_PEER_resolve (parent->peer, &id);
294 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "tree: Finding first hop for %s.\n",
299 struct MeshTunnelTreeNode *aux;
300 struct MeshTunnelTreeNode *old;
303 while (aux != tree->me)
306 GNUNET_PEER_resolve (aux->peer, &id);
307 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "tree: ... checking %s.\n",
312 GNUNET_assert (NULL != aux);
315 GNUNET_PEER_resolve (old->peer, &id);
316 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "tree: It's %s!\n",
320 GNUNET_PEER_resolve (old->peer, hop);
322 GNUNET_PEER_resolve (parent->peer, &id);
323 copy = GNUNET_CONTAINER_multihashmap_get (tree->first_hops, &id.hashPubKey);
325 copy = GNUNET_malloc (sizeof (struct GNUNET_PeerIdentity));
328 (void) GNUNET_CONTAINER_multihashmap_put (tree->first_hops, &id.hashPubKey,
330 GNUNET_CONTAINER_MULTIHASHMAPOPTION_REPLACE);
332 for (n = parent->children_head; NULL != n; n = n->next)
334 tree_node_update_first_hops (tree, n, hop);
340 tree_node_debug (struct MeshTunnelTreeNode *n, uint16_t level)
342 struct MeshTunnelTreeNode *c;
343 struct GNUNET_PeerIdentity id;;
346 for (i = 0; i < level; i++)
347 FPRINTF (stderr, "%s", " ");
348 if (n->status == MESH_PEER_READY)
349 FPRINTF (stderr, "%s", "#");
350 if (n->status == MESH_PEER_SEARCHING)
351 FPRINTF (stderr, "%s", "+");
352 if (n->status == MESH_PEER_RELAY)
353 FPRINTF (stderr, "%s", "-");
354 if (n->status == MESH_PEER_RECONNECTING)
355 FPRINTF (stderr, "%s", "*");
357 GNUNET_PEER_resolve (n->peer, &id);
358 FPRINTF (stderr, "%s, [%u, %p] ", GNUNET_i2s (&id), n->peer, n);
359 if (NULL != n->parent)
361 GNUNET_PEER_resolve (n->parent->peer, &id);
362 FPRINTF (stderr, "(-> %s [%u])\n", GNUNET_i2s (&id), n->parent->peer);
365 FPRINTF (stderr, "%s", "(root)\n");
366 for (c = n->children_head; NULL != c; c = c->next)
367 tree_node_debug (c, level + 1);
372 * Destroys and frees the node and all children
374 * @param parent Parent node to be destroyed
377 tree_node_destroy (struct MeshTunnelTreeNode *parent)
379 struct MeshTunnelTreeNode *n;
380 struct MeshTunnelTreeNode *next;
383 struct GNUNET_PeerIdentity id;
385 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "tree: Destroying node %u\n",
387 GNUNET_PEER_resolve (parent->peer, &id);
388 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "tree: (%s)\n", GNUNET_i2s (&id));
390 n = parent->children_head;
394 tree_node_destroy (n);
397 GNUNET_PEER_change_rc (parent->peer, -1);
398 if (NULL != parent->parent)
399 GNUNET_CONTAINER_DLL_remove (parent->parent->children_head,
400 parent->parent->children_tail, parent);
401 GNUNET_free (parent);
409 * @param peer A short peer id of the root of the tree.
411 * @return A newly allocated and initialized tunnel tree.
413 struct MeshTunnelTree *
414 tree_new (GNUNET_PEER_Id peer)
416 struct MeshTunnelTree *tree;
418 tree = GNUNET_malloc (sizeof (struct MeshTunnelTree));
419 tree->first_hops = GNUNET_CONTAINER_multihashmap_create (32, GNUNET_NO);
420 tree->root = tree_node_new (NULL, peer);
421 tree->root->status = MESH_PEER_ROOT;
425 tree->me = tree->root;
433 * Set the status of a node.
436 * @param peer A short peer id of the node.
437 * @param status New status to set.
440 tree_set_status (struct MeshTunnelTree *tree, GNUNET_PEER_Id peer,
441 enum MeshPeerState status)
443 struct MeshTunnelTreeNode *n;
445 n = tree_find_peer (tree, peer);
453 * Get the status of a node.
455 * @param tree Tree whose node's status we want to now.
456 * @param peer A short peer id of the node.
458 * @return Status of the peer.
461 tree_get_status (struct MeshTunnelTree *tree, GNUNET_PEER_Id peer)
463 struct MeshTunnelTreeNode *n;
465 n = tree_find_peer (tree, peer);
467 return MESH_PEER_INVALID;
473 * Get the id of the predecessor of the local node.
475 * @param tree Tree whose local id we want to now.
477 * @return Short peer id of local peer.
480 tree_get_predecessor (struct MeshTunnelTree *tree)
482 if (NULL != tree->me && NULL != tree->me->parent)
483 return tree->me->parent->peer;
485 return (GNUNET_PEER_Id) 0;
490 * Find the first peer whom to send a packet to go down this path
492 * @param t The tunnel tree to use
493 * @param peer The peerinfo of the peer we are trying to reach
495 * @return peerinfo of the peer who is the first hop in the tunnel
500 struct GNUNET_PeerIdentity *
501 tree_get_first_hop (struct MeshTunnelTree *t, GNUNET_PEER_Id peer)
503 struct GNUNET_PeerIdentity id;
504 struct GNUNET_PeerIdentity *r;
506 GNUNET_PEER_resolve (peer, &id);
507 r = GNUNET_CONTAINER_multihashmap_get (t->first_hops, &id.hashPubKey);
510 struct MeshTunnelTreeNode *n;
512 n = tree_find_peer (t, peer);
513 if (NULL != t->me && NULL != n)
515 tree_node_update_first_hops (t, n, NULL);
516 r = GNUNET_CONTAINER_multihashmap_get (t->first_hops, &id.hashPubKey);
517 GNUNET_assert (NULL != r);
521 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
522 "Tree structure inconsistent! me: %p, n: %p", t->me, n);
532 * Find the given peer in the tree.
534 * @param tree Tree where to look for the peer.
535 * @param peer_id Short ID of the peer to find.
537 * @return Pointer to the node of the peer. NULL if not found.
539 struct MeshTunnelTreeNode *
540 tree_find_peer (struct MeshTunnelTree *tree, GNUNET_PEER_Id peer_id)
542 return tree_node_find_peer (tree->root, peer_id);
547 * Recusively mark peer and children as disconnected, notify client
549 * @param tree Tree this node belongs to
550 * @param parent Node to be clean, potentially with children
551 * @param cb Callback to use to notify about disconnected peers.
552 * @param cbcls Closure for cb.
555 tree_mark_peers_disconnected (struct MeshTunnelTree *tree,
556 struct MeshTunnelTreeNode *parent,
557 MeshTreeCallback cb, void *cbcls)
559 struct GNUNET_PeerIdentity *pi;
560 struct GNUNET_PeerIdentity id;
561 struct MeshTunnelTreeNode *n;
563 for (n = parent->children_head; NULL != n; n = n->next)
565 tree_mark_peers_disconnected (tree, n, cb, cbcls);
567 if (MESH_PEER_READY == parent->status)
570 cb (cbcls, parent->peer);
571 parent->status = MESH_PEER_RECONNECTING;
574 /* Remove and free info about first hop */
575 GNUNET_PEER_resolve (parent->peer, &id);
576 pi = GNUNET_CONTAINER_multihashmap_get (tree->first_hops, &id.hashPubKey);
577 GNUNET_CONTAINER_multihashmap_remove_all (tree->first_hops, &id.hashPubKey);
584 * Iterate over all children of the local node.
586 * @param tree Tree to use. Must have "me" set.
587 * @param cb Callback to call over each child.
588 * @param cb_cls Closure for @c cb.
591 tree_iterate_children (struct MeshTunnelTree *tree, MeshTreeCallback cb,
594 struct MeshTunnelTreeNode *n;
596 if (NULL == tree->me)
601 for (n = tree->me->children_head; NULL != n; n = n->next)
603 cb (cb_cls, n->peer);
609 * Struct to contain a list of pending nodes when iterating a tree.
611 struct MeshTreePendingNode {
616 struct MeshTreePendingNode *next;
621 struct MeshTreePendingNode *prev;
626 struct MeshTunnelTreeNode *node;
631 * Iterate over all nodes in the tree.
633 * @param tree Tree to use..
634 * @param cb Callback to call over each child.
635 * @param cb_cls Closure for @c cb.
637 * TODO: recursive implementation? (s/heap/stack/g)
640 tree_iterate_all (struct MeshTunnelTree *tree,
641 MeshWholeTreeCallback cb,
644 struct MeshTunnelTreeNode *parent;
645 struct MeshTunnelTreeNode *n;
646 struct MeshTreePendingNode *head;
647 struct MeshTreePendingNode *tail;
648 struct MeshTreePendingNode *pending;
650 cb (cb_cls, tree->root->peer, 0);
651 pending = GNUNET_malloc (sizeof (struct MeshTreePendingNode));
652 pending->node = tree->root;
654 GNUNET_CONTAINER_DLL_insert (head, tail, pending);
659 parent = pending->node;
660 GNUNET_CONTAINER_DLL_remove (head, tail, pending);
661 GNUNET_free (pending);
662 for (n = parent->children_head; NULL != n; n = n->next)
664 cb (cb_cls, n->peer, parent->peer);
665 pending = GNUNET_malloc (sizeof (struct MeshTreePendingNode));
667 /* Insert_tail: breadth first, Insert: depth first */
668 GNUNET_CONTAINER_DLL_insert (head, tail, pending);
675 * Iterator to count the children in a tree.
678 count_children_cb (void *cls, GNUNET_PEER_Id peer)
680 unsigned int *i = cls;
687 * Count how many children does the local node have in the tree.
689 * @param tree Tree to use. Must have "me" set.
692 tree_count_children (struct MeshTunnelTree *tree)
697 tree_iterate_children(tree, &count_children_cb, &i);
703 * Recusively update the info about what is the first hop to reach the node
705 * @param tree Tree this nodes belongs to.
706 * @param parent_id Short ID from node form which to start updating.
707 * @param hop If known, ID of the first hop.
708 * If not known, NULL to find out and pass on children.
711 tree_update_first_hops (struct MeshTunnelTree *tree, GNUNET_PEER_Id parent_id,
712 struct GNUNET_PeerIdentity *hop)
714 tree_node_update_first_hops (tree, tree_find_peer (tree, parent_id), hop);
719 * Delete the current path to the peer, including all now unused relays.
720 * The destination peer is NOT destroyed, it is returned in order to either set
721 * a new path to it or destroy it explicitly, taking care of it's child nodes.
723 * @param t Tunnel tree where to delete the path from.
724 * @param peer_id Short ID of the destination peer whose path we want to remove.
725 * @param cb Callback to use to notify about disconnected peers.
726 * @param cbcls Closure for cb.
728 * @return pointer to the pathless node.
729 * NULL when not found
731 struct MeshTunnelTreeNode *
732 tree_del_path (struct MeshTunnelTree *t, GNUNET_PEER_Id peer_id,
733 MeshTreeCallback cb, void *cbcls)
735 struct MeshTunnelTreeNode *parent;
736 struct MeshTunnelTreeNode *node;
737 struct MeshTunnelTreeNode *n;
740 struct GNUNET_PeerIdentity id;
742 GNUNET_PEER_resolve (peer_id, &id);
743 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "tree: Deleting path to %s.\n",
746 if (peer_id == t->root->peer)
749 for (n = t->disconnected_head; NULL != n; n = n->next)
751 if (n->peer == peer_id)
753 /* Was already pathless, waiting for reconnection */
754 GNUNET_CONTAINER_DLL_remove (t->disconnected_head, t->disconnected_tail,
759 n = tree_find_peer (t, peer_id);
765 GNUNET_CONTAINER_DLL_remove (parent->children_head, parent->children_tail, n);
768 while (MESH_PEER_RELAY == parent->status &&
769 NULL == parent->children_head &&
770 parent->peer != t->me->peer)
773 GNUNET_PEER_resolve (parent->peer, &id);
774 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "tree: Deleting node %s.\n",
778 tree_node_destroy (parent);
782 GNUNET_PEER_resolve (parent->peer, &id);
783 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "tree: Not deleted peer %s.\n",
787 tree_mark_peers_disconnected (t, node, cb, cbcls);
794 * Return a newly allocated individual path to reach a peer from the local peer,
795 * according to the path tree of some tunnel.
797 * @param t Tunnel from which to read the path tree.
798 * @param peer Short ID of the destination peer to whom we want a path.
800 * @return A newly allocated individual path to reach the destination peer.
801 * Path must be destroyed afterwards.
803 struct MeshPeerPath *
804 tree_get_path_to_peer (struct MeshTunnelTree *t, GNUNET_PEER_Id peer)
806 struct MeshTunnelTreeNode *n;
807 struct MeshPeerPath *p;
809 n = tree_find_peer (t, peer);
817 /* Building the path (inverted!) */
820 GNUNET_array_append (p->peers, p->length, n->peer);
821 GNUNET_PEER_change_rc (n->peer, 1);
830 GNUNET_array_append (p->peers, p->length, 1);
831 GNUNET_PEER_change_rc (1, 1);
841 * Integrate a stand alone path into the tunnel tree.
842 * If the peer toward which the new path is already in the tree, the peer
843 * and its children will be maked as disconnected and the callback
844 * will be called on each one of them. They will be maked as online only after
845 * receiving a PATH ACK for the new path for each one of them, so the caller
846 * should take care of sending a new CREATE PATH message for each disconnected
849 * @param t Tunnel where to add the new path.
850 * @param p Path to be integrated.
851 * @param cb Callback to use to notify about peers temporarily disconnecting.
852 * @param cbcls Closure for cb.
854 * @return GNUNET_OK in case of success.
855 * GNUNET_SYSERR in case of error.
858 * - go backwards on path looking for each peer in the present tree
859 * - do not disconnect peers until new path is created & connected
862 tree_add_path (struct MeshTunnelTree *t, const struct MeshPeerPath *p,
863 MeshTreeCallback cb, void *cbcls)
865 struct MeshTunnelTreeNode *parent;
866 struct MeshTunnelTreeNode *oldnode;
867 struct MeshTunnelTreeNode *n;
868 struct MeshTunnelTreeNode *c;
869 struct GNUNET_PeerIdentity id;
874 GNUNET_PEER_resolve (p->peers[p->length - 1], &id);
875 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
876 "tree: Adding path [%u] towards peer %s.\n", p->length,
880 GNUNET_assert (0 != p->length);
881 parent = n = t->root;
882 if (n->peer != p->peers[0])
885 return GNUNET_SYSERR;
889 oldnode = tree_del_path (t, p->peers[p->length - 1], cb, cbcls);
890 /* Look for the first node that is not already present in the tree
892 * Assuming that the tree is somewhat balanced, O(log n * log N).
893 * - Length of the path is expected to be log N (size of whole network).
894 * - Each level of the tree is expected to have log n children (size of tree).
896 me = t->root->peer == 1 ? 0 : -1;
897 for (i = 1; i < p->length; i++)
900 GNUNET_PEER_resolve (p->peers[i], &id);
901 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "tree: Looking for peer %s.\n",
905 if (p->peers[i] == 1)
907 for (c = n->children_head; NULL != c; c = c->next)
909 if (c->peer == p->peers[i])
912 GNUNET_PEER_resolve (parent->peer, &id);
913 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
914 "tree: Found in children of %s.\n", GNUNET_i2s (&id));
920 /* If we couldn't find a child equal to path[i], we have reached the end
921 * of the common path. */
926 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "tree: All childen visited.\n");
928 /* Add the rest of the path as a branch from parent. */
929 while (i < p->length)
932 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "tree: Adding peer %u to %u.\n",
933 p->peers[i], parent->peer);
934 GNUNET_PEER_resolve (p->peers[i], &id);
935 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "tree: Adding peer %s.\n",
937 GNUNET_PEER_resolve (parent->peer, &id);
938 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "tree: to %s.\n",
942 if (i == p->length - 1 && NULL != oldnode)
945 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
946 "tree: Putting old node into place.\n");
948 oldnode->parent = parent;
949 GNUNET_CONTAINER_DLL_insert (parent->children_head, parent->children_tail,
951 tree_node_update_first_hops (t, oldnode, NULL);
957 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "tree: Creating new node.\n");
959 n = tree_node_new (parent, p->peers[i]);
960 n->status = MESH_PEER_RELAY;
970 n->status = MESH_PEER_SEARCHING;
972 GNUNET_break (-1 != me);
974 /* Add info about first hop into hashmap. */
975 if (-1 != me && me < p->length - 1)
978 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
979 "MESH: finding first hop (own pos %d/%u)\n", me,
982 GNUNET_PEER_resolve (p->peers[me + 1], &id);
983 tree_update_first_hops (t, p->peers[me + 1], &id);
988 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
989 "MESH: was last in path, not updating first hops (%d/%u)\n",
992 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "tree: New node added.\n");
995 t->me = tree_find_peer (t, 1);
1001 * Notifies a tree that a connection it might be using is broken.
1002 * Marks all peers down the paths as disconnected and notifies the client.
1004 * @param t Tree to use.
1005 * @param p1 Short id of one of the peers (order unimportant)
1006 * @param p2 Short id of one of the peers (order unimportant)
1007 * @param cb Function to call for every peer that is marked as disconnected.
1008 * @param cbcls Closure for cb.
1010 * @return Short ID of the first disconnected peer in the tree.
1013 tree_notify_connection_broken (struct MeshTunnelTree *t, GNUNET_PEER_Id p1,
1014 GNUNET_PEER_Id p2, MeshTreeCallback cb,
1017 struct MeshTunnelTreeNode *n;
1018 struct MeshTunnelTreeNode *c;
1020 n = tree_find_peer (t, p1);
1023 if (NULL != n->parent && n->parent->peer == p2)
1025 tree_mark_peers_disconnected (t, n, cb, cbcls);
1026 GNUNET_CONTAINER_DLL_remove (n->parent->children_head,
1027 n->parent->children_tail, n);
1028 GNUNET_CONTAINER_DLL_insert (t->disconnected_head, t->disconnected_tail, n);
1031 for (c = n->children_head; NULL != c; c = c->next)
1035 tree_mark_peers_disconnected (t, c, cb, cbcls);
1036 GNUNET_CONTAINER_DLL_remove (n->children_head, n->children_tail, c);
1037 GNUNET_CONTAINER_DLL_insert (t->disconnected_head, t->disconnected_tail,
1047 * Deletes a peer from a tunnel, liberating all unused resources on the path to
1048 * it. It shouldn't have children, if it has they will be destroyed as well.
1049 * If the tree is not local and no longer has any paths, the root node will be
1050 * destroyed and marked as NULL.
1052 * @param t Tunnel tree to use.
1053 * @param peer Short ID of the peer to remove from the tunnel tree.
1054 * @param cb Callback to notify client of disconnected peers.
1055 * @param cbcls Closure for cb.
1057 * @return GNUNET_OK or GNUNET_SYSERR
1060 tree_del_peer (struct MeshTunnelTree *t, GNUNET_PEER_Id peer,
1061 MeshTreeCallback cb, void *cbcls)
1063 struct MeshTunnelTreeNode *n;
1065 n = tree_del_path (t, peer, cb, cbcls);
1071 GNUNET_break (NULL == n->children_head);
1072 tree_node_destroy (n);
1073 if (NULL == t->root->children_head && t->me != t->root)
1075 tree_node_destroy (t->root);
1085 * Get the cost of the path relative to the already built tunnel tree.
1087 * @param t The tunnel tree to which compare.
1088 * @param path The individual path to reach a peer. It has to start at the
1089 * root of the tree to be comparable.
1091 * @return Number of hops to reach destination, UINT_MAX in case the peer is not
1094 * TODO: adapt to allow any start / root combination
1095 * TODO: take in account state of the nodes
1098 tree_get_path_cost (struct MeshTunnelTree *t, struct MeshPeerPath *path)
1100 struct MeshTunnelTreeNode *n;
1101 struct MeshTunnelTreeNode *p;
1105 l = path_get_length (path);
1107 if (t->root->peer != path->peers[0])
1112 for (i = 1; i < l; i++)
1114 for (n = p->children_head; NULL != n; n = n->next)
1116 if (path->peers[i] == n->peer)
1130 * Print the tree on stderr
1135 tree_debug (struct MeshTunnelTree *t)
1137 tree_node_debug (t->root, 0);
1142 * Iterator over hash map peer entries and frees all data in it.
1143 * Used prior to destroying a hashmap. Makes you miss anonymous functions in C.
1145 * @param cls closure
1146 * @param key current key code (will no longer contain valid data!!)
1147 * @param value value in the hash map (treated as void *)
1148 * @return GNUNET_YES if we should continue to iterate, GNUNET_NO if not.
1151 iterate_free (void *cls, const struct GNUNET_HashCode * key, void *value)
1153 GNUNET_free (value);
1159 * Destroy the whole tree and free all used memory and Peer_Ids
1161 * @param t Tree to be destroyed
1164 tree_destroy (struct MeshTunnelTree *t)
1167 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "tree: Destroying tree\n");
1169 tree_node_destroy (t->root);
1170 GNUNET_CONTAINER_multihashmap_iterate (t->first_hops, &iterate_free, NULL);
1171 GNUNET_CONTAINER_multihashmap_destroy (t->first_hops);