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3 (C) 2011 Christian Grothoff (and other contributing authors)
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22 * @file mesh/mesh_api_new.c
23 * @brief mesh api: client implementation of mesh service
24 * @author Bartlomiej Polot
29 * - AUXILIARY FUNCTIONS
32 * - API CALL DEFINITIONS
39 #if 0 /* keep Emacsens' auto-indent happy */
46 #include "gnunet_common.h"
47 #include "gnunet_client_lib.h"
48 #include "gnunet_util_lib.h"
49 #include "gnunet_peer_lib.h"
50 #include "gnunet_mesh_service_new.h"
52 #include "mesh_protocol.h"
54 #define MESH_API_MAX_QUEUE 10
56 /******************************************************************************/
57 /************************ DATA STRUCTURES ****************************/
58 /******************************************************************************/
61 * Transmission queue to the service
63 struct GNUNET_MESH_queue
68 struct GNUNET_MESH_queue *next;
69 struct GNUNET_MESH_queue *prev;
72 * Size of the data to follow
84 * Opaque handle to the service.
86 struct GNUNET_MESH_Handle
89 * Handle to the server connection, to send messages later
91 struct GNUNET_CLIENT_Connection *client;
94 * Set of handlers used for processing incoming messages in the tunnels
96 const struct GNUNET_MESH_MessageHandler *message_handlers;
100 * Set of applications that should be claimed to be offered at this node.
101 * Note that this is just informative, the appropiate handlers must be
102 * registered independently and the mapping is up to the developer of the
103 * client application.
105 const GNUNET_MESH_ApplicationType *applications;
109 * Double linked list of the tunnels this client is connected to.
111 struct GNUNET_MESH_Tunnel *tunnels_head;
112 struct GNUNET_MESH_Tunnel *tunnels_tail;
115 * tid of the next tunnel to create (to avoid reusing IDs often)
117 MESH_TunnelNumber next_tid;
120 * Callback for tunnel disconnection
122 GNUNET_MESH_TunnelEndHandler *cleaner;
125 * Handle to cancel pending transmissions in case of disconnection
127 struct GNUNET_CLIENT_TransmitHandle *th;
130 * Closure for all the handlers given by the client
135 * Messages to send to the service
137 struct GNUNET_MESH_queue *queue_head;
138 struct GNUNET_MESH_queue *queue_tail;
141 * Have we started the task to receive messages from the service
142 * yet? We do this after we send the 'MESH_LOCAL_CONNECT' message.
148 * Opaque handle to a tunnel.
150 struct GNUNET_MESH_Tunnel
156 struct GNUNET_MESH_Tunnel *next;
157 struct GNUNET_MESH_Tunnel *prev;
160 * Local ID of the tunnel
162 MESH_TunnelNumber tid;
165 * Owner of the tunnel
167 GNUNET_PEER_Id owner;
170 * Callback to execute when peers connect to the tunnel
172 GNUNET_MESH_TunnelConnectHandler connect_handler;
175 * Callback to execute when peers disconnect to the tunnel
177 GNUNET_MESH_TunnelDisconnectHandler disconnect_handler;
180 * All peers added to the tunnel
182 GNUNET_PEER_Id *peers;
185 * Number of peer added to the tunnel
190 * Closure for the connect/disconnect handlers
195 * Handle to the mesh this tunnel belongs to
197 struct GNUNET_MESH_Handle *mesh;
200 struct GNUNET_MESH_TransmitHandle
202 struct GNUNET_MESH_Tunnel *t;
203 struct GNUNET_MESH_queue *q;
206 /******************************************************************************/
207 /*********************** AUXILIARY FUNCTIONS *************************/
208 /******************************************************************************/
211 * Get the tunnel handler for the tunnel specified by id from the given handle
212 * @param h Mesh handle
213 * @param tid ID of the wanted tunnel
214 * @return handle to the required tunnel or NULL if not found
216 static struct GNUNET_MESH_Tunnel *
217 retrieve_tunnel (struct GNUNET_MESH_Handle *h, MESH_TunnelNumber tid)
219 struct GNUNET_MESH_Tunnel *t;
232 * Get the length of the transmission queue
233 * @param h mesh handle whose queue is to be measured
236 get_queue_length (struct GNUNET_MESH_Handle *h)
238 struct GNUNET_MESH_queue *q;
242 for (q = h->queue_head, i = 0; NULL != q; q = q->next, i++) ;
248 /******************************************************************************/
249 /*********************** RECEIVE HANDLERS ****************************/
250 /******************************************************************************/
253 * Process the new tunnel notification and add it to the tunnels in the handle
255 * @param h The mesh handle
256 * @param msg A message with the details of the new incoming tunnel
259 process_tunnel_create (struct GNUNET_MESH_Handle *h,
260 const struct GNUNET_MESH_TunnelMessage *msg)
262 struct GNUNET_MESH_Tunnel *t;
263 MESH_TunnelNumber tid;
265 tid = ntohl (msg->tunnel_id);
266 if (tid >= GNUNET_MESH_LOCAL_TUNNEL_ID_MARK)
268 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
269 "MESH: received an incoming tunnel with tid in local range (%X)\n",
272 return; //FIXME abort? reconnect?
274 t = GNUNET_malloc (sizeof (struct GNUNET_MESH_Tunnel));
284 * Process the new peer event and notify the upper level of it
286 * @param h The mesh handle
287 * @param msg A message with the details of the peer event
290 process_peer_event (struct GNUNET_MESH_Handle *h,
291 const struct GNUNET_MESH_PeerControl *msg)
293 struct GNUNET_MESH_Tunnel *t;
296 size = ntohs (msg->header.size);
297 if (size != sizeof (struct GNUNET_MESH_PeerControl))
302 t = retrieve_tunnel (h, ntohl (msg->tunnel_id));
308 if (GNUNET_MESSAGE_TYPE_MESH_LOCAL_PEER_CONNECTED == msg->header.type)
310 if (NULL != t->connect_handler)
312 t->connect_handler (t->cls, &msg->peer, NULL); /* FIXME atsi */
317 if (NULL != t->disconnect_handler)
319 t->disconnect_handler (t->cls, &msg->peer);
326 * Process the incoming data packets
328 * @param h The mesh handle
329 * @param msh A message encapsulating the data
332 process_incoming_data (struct GNUNET_MESH_Handle *h,
333 const struct GNUNET_MessageHeader *message)
335 const struct GNUNET_MessageHeader *payload;
336 const struct GNUNET_MESH_MessageHandler *handler;
337 const struct GNUNET_PeerIdentity *peer;
338 struct GNUNET_MESH_Unicast *ucast;
339 struct GNUNET_MESH_Multicast *mcast;
340 struct GNUNET_MESH_ToOrigin *to_orig;
341 struct GNUNET_MESH_Tunnel *t;
345 type = ntohs (message->type);
348 case GNUNET_MESSAGE_TYPE_MESH_UNICAST:
349 ucast = (struct GNUNET_MESH_Unicast *) message;
350 t = retrieve_tunnel (h, ntohl (ucast->tid));
351 payload = (struct GNUNET_MessageHeader *) &ucast[1];
354 case GNUNET_MESSAGE_TYPE_MESH_MULTICAST:
355 mcast = (struct GNUNET_MESH_Multicast *) message;
356 t = retrieve_tunnel (h, ntohl (mcast->tid));
357 payload = (struct GNUNET_MessageHeader *) &mcast[1];
360 case GNUNET_MESSAGE_TYPE_MESH_TO_ORIGIN:
361 to_orig = (struct GNUNET_MESH_ToOrigin *) message;
362 t = retrieve_tunnel (h, ntohl (to_orig->tid));
363 payload = (struct GNUNET_MessageHeader *) &to_orig[1];
364 peer = &to_orig->sender;
375 for (i = 0; i < h->n_handlers; i++)
377 handler = &h->message_handlers[i];
378 if (handler->type == type)
380 if (GNUNET_OK == handler->callback (h->cls, t, NULL, /* FIXME ctx */
381 peer, payload, NULL)) /* FIXME atsi */
383 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
384 "MESH: callback completed successfully\n");
388 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
389 "MESH: callback caused disconnection\n");
390 GNUNET_MESH_disconnect (h);
398 * Function to process all messages received from the service
401 * @param msg message received, NULL on timeout or fatal error
404 msg_received (void *cls, const struct GNUNET_MessageHeader *msg)
406 struct GNUNET_MESH_Handle *h = cls;
408 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "mesh: received a message from MESH\n");
412 h->in_receive = GNUNET_NO;
413 // rather: do_reconnect () -- and set 'in_receive' to NO there...
414 // FIXME: service disconnect, handle!
418 switch (ntohs (msg->type))
420 /* Notify of a new incoming tunnel */
421 case GNUNET_MESSAGE_TYPE_MESH_LOCAL_TUNNEL_CREATE:
422 process_tunnel_create (h, (struct GNUNET_MESH_TunnelMessage *) msg);
424 /* Notify of a new peer or a peer disconnect in the tunnel */
425 case GNUNET_MESSAGE_TYPE_MESH_LOCAL_PEER_CONNECTED:
426 case GNUNET_MESSAGE_TYPE_MESH_LOCAL_PEER_DISCONNECTED:
427 process_peer_event (h, (struct GNUNET_MESH_PeerControl *) msg);
429 /* Notify of a new data packet in the tunnel */
430 case GNUNET_MESSAGE_TYPE_MESH_UNICAST:
431 case GNUNET_MESSAGE_TYPE_MESH_MULTICAST:
432 case GNUNET_MESSAGE_TYPE_MESH_TO_ORIGIN:
433 process_incoming_data (h, msg);
435 /* We shouldn't get any other packages, log and ignore */
437 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
438 "MESH: unsolicited message form service (type %d)\n",
442 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "mesh: message processed\n");
443 GNUNET_CLIENT_receive (h->client, &msg_received, h,
444 GNUNET_TIME_UNIT_FOREVER_REL);
448 /******************************************************************************/
449 /************************ SEND FUNCTIONS ****************************/
450 /******************************************************************************/
453 * Function called to send a message to the service.
454 * "buf" will be NULL and "size" zero if the socket was closed for writing in
457 * @param cls closure, the mesh handle
458 * @param size number of bytes available in buf
459 * @param buf where the callee should write the connect message
460 * @return number of bytes written to buf
463 send_raw (void *cls, size_t size, void *buf)
465 struct GNUNET_MESH_Handle *h = cls;
466 struct GNUNET_MESH_queue *q;
468 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "mesh: Send packet() Buffer %u\n", size);
470 if (0 == size || NULL == buf)
472 // FIXME: disconnect, reconnect, retry?
477 if (sizeof (struct GNUNET_MessageHeader) > size)
480 GNUNET_assert (sizeof (struct GNUNET_MessageHeader) > q->size);
482 GNUNET_CLIENT_notify_transmit_ready (h->client, q->size,
483 GNUNET_TIME_UNIT_FOREVER_REL,
484 GNUNET_YES, &send_raw, h);
487 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "mesh: type: %i\n",
488 ntohs (((struct GNUNET_MessageHeader *) q->data)->type));
489 memcpy (buf, q->data, q->size);
490 GNUNET_free (q->data);
492 GNUNET_CONTAINER_DLL_remove (h->queue_head, h->queue_tail, q);
494 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "mesh: size: %u\n", size);
496 if (NULL != h->queue_head)
498 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "mesh: next size: %u\n",
499 h->queue_head->size);
501 GNUNET_CLIENT_notify_transmit_ready (h->client, h->queue_head->size,
502 GNUNET_TIME_UNIT_FOREVER_REL,
503 GNUNET_YES, &send_raw, h);
505 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "mesh: Send packet() END\n");
506 if (GNUNET_NO == h->in_receive)
508 h->in_receive = GNUNET_YES;
509 GNUNET_CLIENT_receive (h->client, &msg_received, h,
510 GNUNET_TIME_UNIT_FOREVER_REL);
516 * Auxiliary function to send a packet to the service
517 * Takes care of creating a new queue element and calling the tmt_rdy function
519 * @param h mesh handle
520 * @param size size of the packet to transmit
521 * @param data packet itself
524 send_packet (struct GNUNET_MESH_Handle *h, size_t size, void *data)
526 struct GNUNET_MESH_queue *q;
528 q = GNUNET_malloc (sizeof (struct GNUNET_MESH_queue));
531 GNUNET_CONTAINER_DLL_insert_tail (h->queue_head, h->queue_tail, q);
535 GNUNET_CLIENT_notify_transmit_ready (h->client, size,
536 GNUNET_TIME_UNIT_FOREVER_REL,
537 GNUNET_YES, &send_raw, h);
540 /******************************************************************************/
541 /********************** API CALL DEFINITIONS *************************/
542 /******************************************************************************/
545 * Connect to the mesh service.
547 * @param cfg configuration to use
548 * @param cls closure for the various callbacks that follow
549 * (including handlers in the handlers array)
550 * @param cleaner function called when an *inbound* tunnel is destroyed
551 * @param handlers callbacks for messages we care about, NULL-terminated
552 * note that the mesh is allowed to drop notifications about
553 * inbound messages if the client does not process them fast
554 * enough (for this notification type, a bounded queue is used)
555 * @param stypes Application Types the client claims to offer
556 * @return handle to the mesh service
557 * NULL on error (in this case, init is never called)
559 struct GNUNET_MESH_Handle *
560 GNUNET_MESH_connect (const struct GNUNET_CONFIGURATION_Handle *cfg, void *cls,
561 GNUNET_MESH_TunnelEndHandler cleaner,
562 const struct GNUNET_MESH_MessageHandler *handlers,
563 const GNUNET_MESH_ApplicationType *stypes)
565 struct GNUNET_MESH_Handle *h;
566 struct GNUNET_MESH_ClientConnect *msg;
567 GNUNET_MESH_ApplicationType *apps;
573 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "mesh: GNUNET_MESH_connect()\n");
574 h = GNUNET_malloc (sizeof (struct GNUNET_MESH_Handle));
576 h->cleaner = cleaner;
577 h->client = GNUNET_CLIENT_connect ("mesh", cfg);
578 if (h->client == NULL)
586 h->message_handlers = handlers;
587 h->applications = stypes;
588 h->next_tid = 0x80000000;
590 /* count handlers and apps, calculate size */
591 for (h->n_handlers = 0; handlers[h->n_handlers].type; h->n_handlers++) ;
592 for (h->n_applications = 0; stypes[h->n_applications]; h->n_applications++) ;
593 size = sizeof (struct GNUNET_MESH_ClientConnect);
594 size += h->n_handlers * sizeof (uint16_t);
595 size += h->n_applications * sizeof (GNUNET_MESH_ApplicationType);
597 /* build connection packet */
598 msg = GNUNET_malloc (size);
599 msg->header.type = htons (GNUNET_MESSAGE_TYPE_MESH_LOCAL_CONNECT);
600 msg->header.size = htons (size);
601 types = (uint16_t *) & msg[1];
602 for (ntypes = 0; ntypes < h->n_handlers; ntypes++)
604 types[ntypes] = h->message_handlers[ntypes].type;
606 apps = (GNUNET_MESH_ApplicationType *) &types[ntypes];
607 for (napps = 0; napps < h->n_applications; napps++)
609 apps[napps] = h->applications[napps];
611 msg->applications = htons (napps);
612 msg->types = htons (ntypes);
614 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
615 "mesh: Sending %lu bytes long message %d types and %d apps\n",
616 ntohs (msg->header.size), ntypes, napps);
618 send_packet (h, size, msg);
621 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "mesh: GNUNET_MESH_connect() END\n");
628 * Disconnect from the mesh service.
630 * @param handle connection to mesh to disconnect
633 GNUNET_MESH_disconnect (struct GNUNET_MESH_Handle *handle)
635 if (NULL != handle->th)
637 GNUNET_CLIENT_notify_transmit_ready_cancel (handle->th);
639 if (NULL != handle->client)
641 GNUNET_CLIENT_disconnect (handle->client, GNUNET_NO);
643 GNUNET_free (handle);
648 * Create a new tunnel (we're initiator and will be allowed to add/remove peers
651 * @param h mesh handle
652 * @param connect_handler function to call when peers are actually connected
653 * @param disconnect_handler function to call when peers are disconnected
654 * @param handler_cls closure for connect/disconnect handlers
656 struct GNUNET_MESH_Tunnel *
657 GNUNET_MESH_tunnel_create (struct GNUNET_MESH_Handle *h,
658 GNUNET_MESH_TunnelConnectHandler connect_handler,
659 GNUNET_MESH_TunnelDisconnectHandler
660 disconnect_handler, void *handler_cls)
662 struct GNUNET_MESH_Tunnel *t;
663 struct GNUNET_MESH_TunnelMessage *msg;
665 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "mesh: Creating new tunnel\n");
666 t = GNUNET_malloc (sizeof (struct GNUNET_MESH_Tunnel));
668 t->connect_handler = connect_handler;
669 t->disconnect_handler = disconnect_handler;
670 t->cls = handler_cls;
672 t->tid = h->next_tid++;
673 h->next_tid |= GNUNET_MESH_LOCAL_TUNNEL_ID_MARK; // keep in range
675 msg = GNUNET_malloc (sizeof (struct GNUNET_MESH_TunnelMessage));
676 msg->header.type = htons (GNUNET_MESSAGE_TYPE_MESH_LOCAL_TUNNEL_CREATE);
677 msg->header.size = htons (sizeof (struct GNUNET_MESH_TunnelMessage));
678 msg->tunnel_id = htonl (t->tid);
680 send_packet (h, sizeof (struct GNUNET_MESH_TunnelMessage), msg);
687 * Destroy an existing tunnel.
689 * @param tun tunnel handle
692 GNUNET_MESH_tunnel_destroy (struct GNUNET_MESH_Tunnel *tun)
694 struct GNUNET_MESH_Handle *h;
695 struct GNUNET_MESH_TunnelMessage *msg;
697 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "mesh: Destroying tunnel\n");
700 msg = GNUNET_malloc (sizeof (struct GNUNET_MESH_TunnelMessage));
701 msg->header.type = htons (GNUNET_MESSAGE_TYPE_MESH_LOCAL_TUNNEL_DESTROY);
702 msg->header.size = htons (sizeof (struct GNUNET_MESH_TunnelMessage));
703 msg->tunnel_id = htonl (tun->tid);
707 send_packet (h, sizeof (struct GNUNET_MESH_TunnelMessage), msg);
712 * Request that a peer should be added to the tunnel. The existing
713 * connect handler will be called ONCE with either success or failure.
715 * @param tunnel handle to existing tunnel
716 * @param timeout how long to try to establish a connection
717 * @param peer peer to add
720 GNUNET_MESH_peer_request_connect_add (struct GNUNET_MESH_Tunnel *tunnel,
721 struct GNUNET_TIME_Relative timeout,
722 const struct GNUNET_PeerIdentity *peer)
724 struct GNUNET_MESH_PeerControl *msg;
725 GNUNET_PEER_Id peer_id;
728 peer_id = GNUNET_PEER_intern (peer);
729 for (i = 0; i < tunnel->npeers; i++)
731 if (tunnel->peers[i] == peer_id)
733 GNUNET_PEER_change_rc (peer_id, -1);
739 GNUNET_realloc (tunnel->peers, tunnel->npeers * sizeof (GNUNET_PEER_Id));
740 tunnel->peers[tunnel->npeers - 1] = peer_id;
742 msg = GNUNET_malloc (sizeof (struct GNUNET_MESH_PeerControl));
743 msg->header.size = htons (sizeof (struct GNUNET_MESH_PeerControl));
744 msg->header.type = htons (GNUNET_MESSAGE_TYPE_MESH_LOCAL_CONNECT_PEER_ADD);
745 msg->tunnel_id = htonl (tunnel->tid);
746 memcpy (&msg->peer, peer, sizeof (struct GNUNET_PeerIdentity));
748 send_packet (tunnel->mesh, sizeof (struct GNUNET_MESH_PeerControl), msg);
750 // tunnel->connect_handler (tunnel->cls, peer, NULL); FIXME call this later
751 // TODO: remember timeout
757 * Request that a peer should be removed from the tunnel. The existing
758 * disconnect handler will be called ONCE if we were connected.
760 * @param tunnel handle to existing tunnel
761 * @param peer peer to remove
764 GNUNET_MESH_peer_request_connect_del (struct GNUNET_MESH_Tunnel *tunnel,
765 const struct GNUNET_PeerIdentity *peer)
767 struct GNUNET_MESH_PeerControl *msg;
768 GNUNET_PEER_Id peer_id;
771 peer_id = GNUNET_PEER_search (peer);
774 for (i = 0; i < tunnel->npeers; i++)
776 if (tunnel->peers[i] == peer_id)
778 GNUNET_PEER_change_rc (peer_id, -1);
780 while (i < tunnel->npeers)
782 tunnel->peers[i] = tunnel->peers[i + 1];
786 GNUNET_realloc (tunnel->peers,
787 tunnel->npeers * sizeof (GNUNET_PEER_Id));
788 msg = GNUNET_malloc (sizeof (struct GNUNET_MESH_PeerControl));
789 msg->header.size = htons (sizeof (struct GNUNET_MESH_PeerControl));
791 htons (GNUNET_MESSAGE_TYPE_MESH_LOCAL_CONNECT_PEER_DEL);
792 msg->tunnel_id = htonl (tunnel->tid);
793 memcpy (&msg->peer, peer, sizeof (struct GNUNET_PeerIdentity));
795 send_packet (tunnel->mesh, sizeof (struct GNUNET_MESH_PeerControl), msg);
800 // TODO: remember timeout
806 * Request that the mesh should try to connect to a peer supporting the given
809 * @param tunnel handle to existing tunnel
810 * @param timeout how long to try to establish a connection
811 * @param app_type application type that must be supported by the peer (MESH
812 * should discover peer in proximity handling this type)
815 GNUNET_MESH_peer_request_connect_by_type (struct GNUNET_MESH_Tunnel *tunnel,
816 struct GNUNET_TIME_Relative timeout,
817 GNUNET_MESH_ApplicationType app_type)
819 struct GNUNET_MESH_ConnectPeerByType *msg;
821 msg = GNUNET_malloc (sizeof (struct GNUNET_MESH_ConnectPeerByType));
822 msg->header.size = htons (sizeof (struct GNUNET_MESH_ConnectPeerByType));
824 htons (GNUNET_MESSAGE_TYPE_MESH_LOCAL_CONNECT_PEER_BY_TYPE);
825 msg->tunnel_id = htonl (tunnel->tid);
826 msg->type = htonl (app_type);
828 send_packet (tunnel->mesh, sizeof (struct GNUNET_MESH_ConnectPeerByType),
830 // TODO: remember timeout
836 * Ask the mesh to call "notify" once it is ready to transmit the
837 * given number of bytes to the specified "target". If we are not yet
838 * connected to the specified peer, a call to this function will cause
839 * us to try to establish a connection.
841 * @param tunnel tunnel to use for transmission
842 * @param cork is corking allowed for this transmission?
843 * @param priority how important is the message?
844 * @param maxdelay how long can the message wait?
845 * @param target destination for the message,
846 * NULL for multicast to all tunnel targets
847 * @param notify_size how many bytes of buffer space does notify want?
848 * @param notify function to call when buffer space is available;
849 * will be called with NULL on timeout or if the overall queue
850 * for this peer is larger than queue_size and this is currently
851 * the message with the lowest priority
852 * @param notify_cls closure for notify
853 * @return non-NULL if the notify callback was queued,
854 * NULL if we can not even queue the request (insufficient
855 * memory); if NULL is returned, "notify" will NOT be called.
857 struct GNUNET_MESH_TransmitHandle *
858 GNUNET_MESH_notify_transmit_ready (struct GNUNET_MESH_Tunnel *tunnel, int cork,
860 struct GNUNET_TIME_Relative maxdelay,
861 const struct GNUNET_PeerIdentity *target,
863 GNUNET_CONNECTION_TransmitReadyNotify notify,
866 struct GNUNET_MESH_TransmitHandle *handle;
868 handle = GNUNET_malloc (sizeof (struct GNUNET_MESH_TransmitHandle));
870 handle->q = GNUNET_malloc (sizeof (struct GNUNET_MESH_queue));
871 handle->q->size = notify_size;
872 handle->q->data = GNUNET_malloc (notify_size);
874 if (get_queue_length (tunnel->mesh) < MESH_API_MAX_QUEUE)
876 notify (notify_cls, notify_size, handle->q->data);
877 GNUNET_CONTAINER_DLL_insert_tail (tunnel->mesh->queue_head,
878 tunnel->mesh->queue_tail, handle->q);
882 // TODO dataless - queue
890 * Cancel the specified transmission-ready notification.
892 * @param th handle that was returned by "notify_transmit_ready".
895 GNUNET_MESH_notify_transmit_ready_cancel (struct GNUNET_MESH_TransmitHandle *th)
897 GNUNET_CONTAINER_DLL_remove (th->t->mesh->queue_head, th->t->mesh->queue_tail,
899 // TODO remove from dataless queue
900 GNUNET_free (th->q->data);
906 #if 0 /* keep Emacsens' auto-indent happy */