2 This file is part of GNUnet.
3 (C) 2009-2013 Christian Grothoff (and other contributing authors)
5 GNUnet is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published
7 by the Free Software Foundation; either version 3, or (at your
8 option) any later version.
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11 WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with GNUnet; see the file COPYING. If not, write to the
17 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA.
22 * @file transport/transport_api.c
23 * @brief library to access the low-level P2P IO service
24 * @author Christian Grothoff
30 #include "gnunet_util_lib.h"
31 #include "gnunet_constants.h"
32 #include "gnunet_arm_service.h"
33 #include "gnunet_hello_lib.h"
34 #include "gnunet_protocols.h"
35 #include "gnunet_transport_service.h"
36 #include "transport.h"
38 #define LOG(kind,...) GNUNET_log_from (kind, "transport-api",__VA_ARGS__)
41 * How large to start with for the hashmap of neighbours.
43 #define STARTING_NEIGHBOURS_SIZE 16
46 * Handle for a message that should be transmitted to the service.
47 * Used for both control messages and normal messages.
49 struct GNUNET_TRANSPORT_TransmitHandle
53 * We keep all requests in a DLL.
55 struct GNUNET_TRANSPORT_TransmitHandle *next;
58 * We keep all requests in a DLL.
60 struct GNUNET_TRANSPORT_TransmitHandle *prev;
63 * Neighbour for this handle, NULL for control messages.
65 struct Neighbour *neighbour;
68 * Function to call when notify_size bytes are available
71 GNUNET_CONNECTION_TransmitReadyNotify notify;
79 * Timeout for this request, 0 for control messages.
81 struct GNUNET_TIME_Absolute timeout;
84 * Task to trigger request timeout if the request is stalled due to
87 GNUNET_SCHEDULER_TaskIdentifier timeout_task;
90 * How many bytes is our notify callback waiting for?
95 * How important is this message? Not used for control messages.
103 * Entry in hash table of all of our current neighbours.
108 * Overall transport handle.
110 struct GNUNET_TRANSPORT_Handle *h;
113 * Active transmit handle or NULL.
115 struct GNUNET_TRANSPORT_TransmitHandle *th;
118 * Identity of this neighbour.
120 struct GNUNET_PeerIdentity id;
123 * Outbound bandwidh tracker.
125 struct GNUNET_BANDWIDTH_Tracker out_tracker;
128 * Entry in our readyness heap (which is sorted by 'next_ready'
129 * value). NULL if there is no pending transmission request for
130 * this neighbour or if we're waiting for 'is_ready' to become
131 * true AFTER the 'out_tracker' suggested that this peer's quota
132 * has been satisfied (so once 'is_ready' goes to GNUNET_YES,
133 * we should immediately go back into the heap).
135 struct GNUNET_CONTAINER_HeapNode *hn;
138 * Is this peer currently ready to receive a message?
143 * Sending consumed more bytes on wire than payload was announced
144 * This overhead is added to the delay of next sending operation
146 size_t traffic_overhead;
151 * Linked list of functions to call whenever our HELLO is updated.
153 struct GNUNET_TRANSPORT_GetHelloHandle
157 * This is a doubly linked list.
159 struct GNUNET_TRANSPORT_GetHelloHandle *next;
162 * This is a doubly linked list.
164 struct GNUNET_TRANSPORT_GetHelloHandle *prev;
169 struct GNUNET_TRANSPORT_Handle *handle;
172 * Callback to call once we got our HELLO.
174 GNUNET_TRANSPORT_HelloUpdateCallback rec;
177 * Task for calling the HelloUpdateCallback when we already have a HELLO
179 GNUNET_SCHEDULER_TaskIdentifier notify_task;
182 * Closure for @e rec.
189 * Linked list for all try-connect requests
191 struct GNUNET_TRANSPORT_TryConnectHandle
196 struct GNUNET_TRANSPORT_TryConnectHandle *prev;
201 struct GNUNET_TRANSPORT_TryConnectHandle *next;
203 struct GNUNET_PeerIdentity pid;
205 struct GNUNET_TRANSPORT_Handle *th;
207 struct GNUNET_TRANSPORT_TransmitHandle *tth;
209 GNUNET_TRANSPORT_TryConnectCallback cb;
219 * Linked list for all try-connect requests
221 struct GNUNET_TRANSPORT_OfferHelloHandle
226 struct GNUNET_TRANSPORT_OfferHelloHandle *prev;
231 struct GNUNET_TRANSPORT_OfferHelloHandle *next;
233 struct GNUNET_TRANSPORT_Handle *th;
235 struct GNUNET_TRANSPORT_TransmitHandle *tth;
237 GNUNET_SCHEDULER_Task cont;
240 * Closure for @e cont
244 struct GNUNET_MessageHeader *msg;
249 * Handle for the transport service (includes all of the
250 * state for the transport service).
252 struct GNUNET_TRANSPORT_Handle
256 * Closure for the callbacks.
261 * Function to call for received data.
263 GNUNET_TRANSPORT_ReceiveCallback rec;
266 * function to call on connect events
268 GNUNET_TRANSPORT_NotifyConnect nc_cb;
271 * function to call on disconnect events
273 GNUNET_TRANSPORT_NotifyDisconnect nd_cb;
276 * Head of DLL of control messages.
278 struct GNUNET_TRANSPORT_TransmitHandle *control_head;
281 * Tail of DLL of control messages.
283 struct GNUNET_TRANSPORT_TransmitHandle *control_tail;
286 * The current HELLO message for this peer. Updated
287 * whenever transports change their addresses.
289 struct GNUNET_HELLO_Message *my_hello;
292 * My client connection to the transport service.
294 struct GNUNET_CLIENT_Connection *client;
297 * Handle to our registration with the client for notification.
299 struct GNUNET_CLIENT_TransmitHandle *cth;
302 * Linked list of pending requests for our HELLO.
304 struct GNUNET_TRANSPORT_GetHelloHandle *hwl_head;
307 * Linked list of pending requests for our HELLO.
309 struct GNUNET_TRANSPORT_GetHelloHandle *hwl_tail;
312 * Linked list of pending try connect requests head
314 struct GNUNET_TRANSPORT_TryConnectHandle *tc_head;
317 * Linked list of pending try connect requests tail
319 struct GNUNET_TRANSPORT_TryConnectHandle *tc_tail;
322 * Linked list of pending offer HELLO requests head
324 struct GNUNET_TRANSPORT_OfferHelloHandle *oh_head;
327 * Linked list of pending offer HELLO requests tail
329 struct GNUNET_TRANSPORT_OfferHelloHandle *oh_tail;
334 const struct GNUNET_CONFIGURATION_Handle *cfg;
337 * Hash map of the current connected neighbours of this peer.
338 * Maps peer identities to 'struct Neighbour' entries.
340 struct GNUNET_CONTAINER_MultiPeerMap *neighbours;
343 * Heap sorting peers with pending messages by the timestamps that
344 * specify when we could next send a message to the respective peer.
345 * Excludes control messages (which can always go out immediately).
346 * Maps time stamps to 'struct Neighbour' entries.
348 struct GNUNET_CONTAINER_Heap *ready_heap;
351 * Peer identity as assumed by this process, or all zeros.
353 struct GNUNET_PeerIdentity self;
356 * ID of the task trying to reconnect to the service.
358 GNUNET_SCHEDULER_TaskIdentifier reconnect_task;
361 * ID of the task trying to trigger transmission for a peer while
362 * maintaining bandwidth quotas. In use if there are no control
363 * messages and the smallest entry in the 'ready_heap' has a time
364 * stamp in the future.
366 GNUNET_SCHEDULER_TaskIdentifier quota_task;
369 * Delay until we try to reconnect.
371 struct GNUNET_TIME_Relative reconnect_delay;
374 * Should we check that @e self matches what the service thinks?
375 * (if #GNUNET_NO, then @e self is all zeros!).
380 * Reconnect in progress
388 * Schedule the task to send one message, either from the control
389 * list or the peer message queues to the service.
391 * @param h transport service to schedule a transmission for
394 schedule_transmission (struct GNUNET_TRANSPORT_Handle *h);
398 * Function that will schedule the job that will try
399 * to connect us again to the client.
401 * @param h transport service to reconnect
404 disconnect_and_schedule_reconnect (struct GNUNET_TRANSPORT_Handle *h);
408 * Get the neighbour list entry for the given peer
410 * @param h our context
411 * @param peer peer to look up
412 * @return NULL if no such peer entry exists
414 static struct Neighbour *
415 neighbour_find (struct GNUNET_TRANSPORT_Handle *h,
416 const struct GNUNET_PeerIdentity *peer)
418 return GNUNET_CONTAINER_multipeermap_get (h->neighbours, peer);
423 * Add neighbour to our list
425 * @return NULL if this API is currently disconnecting from the service
427 static struct Neighbour *
428 neighbour_add (struct GNUNET_TRANSPORT_Handle *h,
429 const struct GNUNET_PeerIdentity *pid)
433 LOG (GNUNET_ERROR_TYPE_DEBUG,
434 "Creating entry for neighbour `%4s'.\n",
436 n = GNUNET_new (struct Neighbour);
439 n->is_ready = GNUNET_YES;
440 n->traffic_overhead = 0;
441 GNUNET_BANDWIDTH_tracker_init (&n->out_tracker,
442 GNUNET_CONSTANTS_DEFAULT_BW_IN_OUT,
443 MAX_BANDWIDTH_CARRY_S);
444 GNUNET_assert (GNUNET_OK ==
445 GNUNET_CONTAINER_multipeermap_put (h->neighbours,
447 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
453 * Iterator over hash map entries, for deleting state of a neighbour.
455 * @param cls the `struct GNUNET_TRANSPORT_Handle *`
456 * @param key peer identity
457 * @param value value in the hash map, the neighbour entry to delete
458 * @return #GNUNET_YES if we should continue to
463 neighbour_delete (void *cls,
464 const struct GNUNET_PeerIdentity *key, void *value)
466 struct GNUNET_TRANSPORT_Handle *handle = cls;
467 struct Neighbour *n = value;
469 if (NULL != handle->nd_cb)
470 handle->nd_cb (handle->cls, &n->id);
471 GNUNET_assert (NULL == n->th);
472 GNUNET_assert (NULL == n->hn);
473 GNUNET_assert (GNUNET_YES ==
474 GNUNET_CONTAINER_multipeermap_remove (handle->neighbours, key,
482 * Function we use for handling incoming messages.
484 * @param cls closure (struct GNUNET_TRANSPORT_Handle *)
485 * @param msg message received, NULL on timeout or fatal error
488 demultiplexer (void *cls, const struct GNUNET_MessageHeader *msg)
490 struct GNUNET_TRANSPORT_Handle *h = cls;
491 const struct DisconnectInfoMessage *dim;
492 const struct ConnectInfoMessage *cim;
493 const struct InboundMessage *im;
494 const struct GNUNET_MessageHeader *imm;
495 const struct SendOkMessage *okm;
496 const struct QuotaSetMessage *qm;
497 struct GNUNET_TRANSPORT_GetHelloHandle *hwl;
498 struct GNUNET_TRANSPORT_GetHelloHandle *next_hwl;
500 struct GNUNET_PeerIdentity me;
503 uint32_t bytes_physical;
505 GNUNET_assert (NULL != h->client);
508 LOG (GNUNET_ERROR_TYPE_DEBUG,
509 "Error receiving from transport service, disconnecting temporarily.\n");
510 disconnect_and_schedule_reconnect (h);
513 GNUNET_CLIENT_receive (h->client, &demultiplexer, h,
514 GNUNET_TIME_UNIT_FOREVER_REL);
515 size = ntohs (msg->size);
516 switch (ntohs (msg->type))
518 case GNUNET_MESSAGE_TYPE_HELLO:
520 GNUNET_HELLO_get_id ((const struct GNUNET_HELLO_Message *) msg, &me))
525 LOG (GNUNET_ERROR_TYPE_DEBUG,
526 "Receiving (my own) `%s' message, I am `%4s'.\n", "HELLO",
528 GNUNET_free_non_null (h->my_hello);
530 if (size < sizeof (struct GNUNET_MessageHeader))
535 h->my_hello = GNUNET_malloc (size);
536 memcpy (h->my_hello, msg, size);
540 next_hwl = hwl->next;
541 hwl->rec (hwl->rec_cls,
542 (const struct GNUNET_MessageHeader *) h->my_hello);
546 case GNUNET_MESSAGE_TYPE_TRANSPORT_CONNECT:
547 if (size < sizeof (struct ConnectInfoMessage))
552 cim = (const struct ConnectInfoMessage *) msg;
554 sizeof (struct ConnectInfoMessage))
559 LOG (GNUNET_ERROR_TYPE_DEBUG,
560 "Receiving `%s' message for `%4s'.\n",
561 "CONNECT", GNUNET_i2s (&cim->id));
562 n = neighbour_find (h, &cim->id);
568 n = neighbour_add (h, &cim->id);
569 LOG (GNUNET_ERROR_TYPE_DEBUG,
570 "Receiving `%s' message for `%4s' with quota %u\n",
572 GNUNET_i2s (&cim->id),
573 ntohl (cim->quota_out.value__));
574 GNUNET_BANDWIDTH_tracker_update_quota (&n->out_tracker, cim->quota_out);
575 if (h->nc_cb != NULL)
576 h->nc_cb (h->cls, &n->id);
578 case GNUNET_MESSAGE_TYPE_TRANSPORT_DISCONNECT:
579 if (size != sizeof (struct DisconnectInfoMessage))
584 dim = (const struct DisconnectInfoMessage *) msg;
585 GNUNET_break (ntohl (dim->reserved) == 0);
586 LOG (GNUNET_ERROR_TYPE_DEBUG,
587 "Receiving `%s' message for `%4s'.\n",
588 "DISCONNECT", GNUNET_i2s (&dim->peer));
589 n = neighbour_find (h, &dim->peer);
595 neighbour_delete (h, &dim->peer, n);
597 case GNUNET_MESSAGE_TYPE_TRANSPORT_SEND_OK:
598 if (size != sizeof (struct SendOkMessage))
603 okm = (const struct SendOkMessage *) msg;
604 bytes_msg = ntohl (okm->bytes_msg);
605 bytes_physical = ntohl (okm->bytes_physical);
606 LOG (GNUNET_ERROR_TYPE_DEBUG, "Receiving `%s' message, transmission %s.\n",
607 "SEND_OK", ntohl (okm->success) == GNUNET_OK ? "succeeded" : "failed");
609 n = neighbour_find (h, &okm->peer);
613 if (bytes_physical >= bytes_msg)
615 LOG (GNUNET_ERROR_TYPE_DEBUG, "Overhead for %u byte message: %u \n",
616 bytes_msg, bytes_physical - bytes_msg);
617 n->traffic_overhead += bytes_physical - bytes_msg;
619 GNUNET_break (GNUNET_NO == n->is_ready);
620 n->is_ready = GNUNET_YES;
621 if ((NULL != n->th) && (NULL == n->hn))
623 GNUNET_assert (GNUNET_SCHEDULER_NO_TASK != n->th->timeout_task);
624 GNUNET_SCHEDULER_cancel (n->th->timeout_task);
625 n->th->timeout_task = GNUNET_SCHEDULER_NO_TASK;
626 /* we've been waiting for this (congestion, not quota,
627 * caused delayed transmission) */
628 n->hn = GNUNET_CONTAINER_heap_insert (h->ready_heap, n, 0);
629 schedule_transmission (h);
632 case GNUNET_MESSAGE_TYPE_TRANSPORT_RECV:
633 LOG (GNUNET_ERROR_TYPE_DEBUG,
634 "Receiving `%s' message.\n",
637 sizeof (struct InboundMessage) + sizeof (struct GNUNET_MessageHeader))
642 im = (const struct InboundMessage *) msg;
643 imm = (const struct GNUNET_MessageHeader *) &im[1];
644 if (ntohs (imm->size) + sizeof (struct InboundMessage) != size)
649 LOG (GNUNET_ERROR_TYPE_DEBUG,
650 "Received message of type %u from `%4s'.\n",
651 ntohs (imm->type), GNUNET_i2s (&im->peer));
652 n = neighbour_find (h, &im->peer);
659 h->rec (h->cls, &im->peer, imm);
661 case GNUNET_MESSAGE_TYPE_TRANSPORT_SET_QUOTA:
662 LOG (GNUNET_ERROR_TYPE_DEBUG,
663 "Receiving `%s' message.\n", "SET_QUOTA");
664 if (size != sizeof (struct QuotaSetMessage))
669 qm = (const struct QuotaSetMessage *) msg;
670 n = neighbour_find (h, &qm->peer);
673 LOG (GNUNET_ERROR_TYPE_DEBUG,
674 "Receiving `%s' message for `%4s' with quota %u\n",
676 GNUNET_i2s (&qm->peer),
677 ntohl (qm->quota.value__));
678 GNUNET_BANDWIDTH_tracker_update_quota (&n->out_tracker, qm->quota);
681 LOG (GNUNET_ERROR_TYPE_ERROR,
682 _("Received unexpected message of type %u in %s:%u\n"),
683 ntohs (msg->type), __FILE__, __LINE__);
691 * A transmission request could not be satisfied because of
692 * network congestion. Notify the initiator and clean up.
694 * @param cls the `struct GNUNET_TRANSPORT_TransmitHandle`
695 * @param tc scheduler context
698 timeout_request_due_to_congestion (void *cls,
699 const struct GNUNET_SCHEDULER_TaskContext *tc)
701 struct GNUNET_TRANSPORT_TransmitHandle *th = cls;
702 struct Neighbour *n = th->neighbour;
704 n->th->timeout_task = GNUNET_SCHEDULER_NO_TASK;
705 GNUNET_assert (th == n->th);
706 GNUNET_assert (NULL == n->hn);
708 th->notify (th->notify_cls, 0, NULL);
714 * Transmit message(s) to service.
716 * @param cls handle to transport
717 * @param size number of bytes available in buf
718 * @param buf where to copy the message
719 * @return number of bytes copied to buf
722 transport_notify_ready (void *cls, size_t size, void *buf)
724 struct GNUNET_TRANSPORT_Handle *h = cls;
725 struct GNUNET_TRANSPORT_TransmitHandle *th;
728 struct OutboundMessage obm;
733 GNUNET_assert (NULL != h->client);
737 /* transmission failed */
738 disconnect_and_schedule_reconnect (h);
744 /* first send control messages */
745 while ((NULL != (th = h->control_head)) && (th->notify_size <= size))
747 GNUNET_CONTAINER_DLL_remove (h->control_head, h->control_tail, th);
748 nret = th->notify (th->notify_cls, size, &cbuf[ret]);
749 LOG (GNUNET_ERROR_TYPE_DEBUG, "Added %u bytes of control message at %u\n",
756 /* then, if possible and no control messages pending, send data messages */
757 while ((NULL == h->control_head) &&
758 (NULL != (n = GNUNET_CONTAINER_heap_peek (h->ready_heap))))
760 if (GNUNET_YES != n->is_ready)
762 /* peer not ready, wait for notification! */
763 GNUNET_assert (n == GNUNET_CONTAINER_heap_remove_root (h->ready_heap));
765 GNUNET_assert (GNUNET_SCHEDULER_NO_TASK == n->th->timeout_task);
766 n->th->timeout_task =
767 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_absolute_get_remaining
769 &timeout_request_due_to_congestion,
774 if (th->notify_size + sizeof (struct OutboundMessage) > size)
775 break; /* does not fit */
776 if (GNUNET_BANDWIDTH_tracker_get_delay
777 (&n->out_tracker, th->notify_size).rel_value_us > 0)
778 break; /* too early */
779 GNUNET_assert (n == GNUNET_CONTAINER_heap_remove_root (h->ready_heap));
782 n->is_ready = GNUNET_NO;
783 GNUNET_assert (size >= sizeof (struct OutboundMessage));
785 th->notify (th->notify_cls, size - sizeof (struct OutboundMessage),
786 &cbuf[ret + sizeof (struct OutboundMessage)]);
787 GNUNET_assert (mret <= size - sizeof (struct OutboundMessage));
790 GNUNET_assert (mret + sizeof (struct OutboundMessage) <
791 GNUNET_SERVER_MAX_MESSAGE_SIZE);
792 obm.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SEND);
793 obm.header.size = htons (mret + sizeof (struct OutboundMessage));
794 obm.priority = htonl (th->priority);
796 GNUNET_TIME_relative_hton (GNUNET_TIME_absolute_get_remaining
799 memcpy (&cbuf[ret], &obm, sizeof (struct OutboundMessage));
800 ret += (mret + sizeof (struct OutboundMessage));
801 size -= (mret + sizeof (struct OutboundMessage));
802 GNUNET_BANDWIDTH_tracker_consume (&n->out_tracker, mret);
806 /* if there are more pending messages, try to schedule those */
807 schedule_transmission (h);
808 LOG (GNUNET_ERROR_TYPE_DEBUG,
809 "Transmitting %u bytes to transport service\n",
816 * Schedule the task to send one message, either from the control
817 * list or the peer message queues to the service.
819 * @param cls transport service to schedule a transmission for
820 * @param tc scheduler context
823 schedule_transmission_task (void *cls,
824 const struct GNUNET_SCHEDULER_TaskContext *tc)
826 struct GNUNET_TRANSPORT_Handle *h = cls;
828 struct GNUNET_TRANSPORT_TransmitHandle *th;
831 h->quota_task = GNUNET_SCHEDULER_NO_TASK;
832 GNUNET_assert (NULL != h->client);
833 /* destroy all requests that have timed out */
834 while ((NULL != (n = GNUNET_CONTAINER_heap_peek (h->ready_heap))) &&
835 (0 == GNUNET_TIME_absolute_get_remaining (n->th->timeout).rel_value_us))
837 /* notify client that the request could not be satisfied within
838 * the given time constraints */
841 GNUNET_assert (n == GNUNET_CONTAINER_heap_remove_root (h->ready_heap));
843 LOG (GNUNET_ERROR_TYPE_DEBUG,
844 "Signalling timeout for transmission to peer %s due to congestion\n",
845 GNUNET_i2s (&n->id));
846 GNUNET_assert (0 == th->notify (th->notify_cls, 0, NULL));
851 if (NULL != h->control_head)
853 size = h->control_head->notify_size;
857 n = GNUNET_CONTAINER_heap_peek (h->ready_heap);
859 return; /* no pending messages */
860 size = n->th->notify_size + sizeof (struct OutboundMessage);
862 LOG (GNUNET_ERROR_TYPE_DEBUG, "Calling notify_transmit_ready\n");
864 GNUNET_CLIENT_notify_transmit_ready (h->client, size,
865 GNUNET_TIME_UNIT_FOREVER_REL,
866 GNUNET_NO, &transport_notify_ready,
868 GNUNET_assert (NULL != h->cth);
873 * Schedule the task to send one message, either from the control
874 * list or the peer message queues to the service.
876 * @param h transport service to schedule a transmission for
879 schedule_transmission (struct GNUNET_TRANSPORT_Handle *h)
881 struct GNUNET_TIME_Relative delay;
884 GNUNET_assert (NULL != h->client);
885 if (h->quota_task != GNUNET_SCHEDULER_NO_TASK)
887 GNUNET_SCHEDULER_cancel (h->quota_task);
888 h->quota_task = GNUNET_SCHEDULER_NO_TASK;
890 if (NULL != h->control_head)
891 delay = GNUNET_TIME_UNIT_ZERO;
892 else if (NULL != (n = GNUNET_CONTAINER_heap_peek (h->ready_heap)))
895 GNUNET_BANDWIDTH_tracker_get_delay (&n->out_tracker,
896 n->th->notify_size + n->traffic_overhead);
897 n->traffic_overhead = 0;
900 return; /* no work to be done */
901 LOG (GNUNET_ERROR_TYPE_DEBUG,
902 "Scheduling next transmission to service in %s\n",
903 GNUNET_STRINGS_relative_time_to_string (delay, GNUNET_YES));
905 GNUNET_SCHEDULER_add_delayed (delay, &schedule_transmission_task, h);
910 * Queue control request for transmission to the transport
913 * @param h handle to the transport service
914 * @param size number of bytes to be transmitted
915 * @param notify function to call to get the content
916 * @param notify_cls closure for notify
917 * @return a `struct GNUNET_TRANSPORT_TransmitHandle`
919 static struct GNUNET_TRANSPORT_TransmitHandle *
920 schedule_control_transmit (struct GNUNET_TRANSPORT_Handle *h, size_t size,
921 GNUNET_CONNECTION_TransmitReadyNotify notify,
924 struct GNUNET_TRANSPORT_TransmitHandle *th;
926 LOG (GNUNET_ERROR_TYPE_DEBUG,
927 "Control transmit of %u bytes requested\n",
929 th = GNUNET_new (struct GNUNET_TRANSPORT_TransmitHandle);
931 th->notify_cls = notify_cls;
932 th->notify_size = size;
933 GNUNET_CONTAINER_DLL_insert_tail (h->control_head, h->control_tail, th);
934 schedule_transmission (h);
940 * Transmit START message to service.
943 * @param size number of bytes available in buf
944 * @param buf where to copy the message
945 * @return number of bytes copied to buf
948 send_start (void *cls, size_t size, void *buf)
950 struct GNUNET_TRANSPORT_Handle *h = cls;
951 struct StartMessage s;
956 /* Can only be shutdown, just give up */
957 LOG (GNUNET_ERROR_TYPE_DEBUG,
958 "Shutdown while trying to transmit `%s' request.\n",
962 LOG (GNUNET_ERROR_TYPE_DEBUG,
963 "Transmitting `%s' request.\n",
965 GNUNET_assert (size >= sizeof (struct StartMessage));
966 s.header.size = htons (sizeof (struct StartMessage));
967 s.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_START);
973 s.options = htonl (options);
975 memcpy (buf, &s, sizeof (struct StartMessage));
976 GNUNET_CLIENT_receive (h->client, &demultiplexer, h,
977 GNUNET_TIME_UNIT_FOREVER_REL);
978 return sizeof (struct StartMessage);
983 * Try again to connect to transport service.
985 * @param cls the handle to the transport service
986 * @param tc scheduler context
989 reconnect (void *cls,
990 const struct GNUNET_SCHEDULER_TaskContext *tc)
992 struct GNUNET_TRANSPORT_Handle *h = cls;
994 h->reconnect_task = GNUNET_SCHEDULER_NO_TASK;
995 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
997 /* shutdown, just give up */
1000 LOG (GNUNET_ERROR_TYPE_DEBUG,
1001 "Connecting to transport service.\n");
1002 GNUNET_assert (NULL == h->client);
1003 GNUNET_assert (NULL == h->control_head);
1004 GNUNET_assert (NULL == h->control_tail);
1005 h->client = GNUNET_CLIENT_connect ("transport", h->cfg);
1006 GNUNET_assert (NULL != h->client);
1007 schedule_control_transmit (h, sizeof (struct StartMessage), &send_start, h);
1012 * Function that will schedule the job that will try
1013 * to connect us again to the client.
1015 * @param h transport service to reconnect
1018 disconnect_and_schedule_reconnect (struct GNUNET_TRANSPORT_Handle *h)
1020 struct GNUNET_TRANSPORT_TransmitHandle *th;
1022 GNUNET_assert (h->reconnect_task == GNUNET_SCHEDULER_NO_TASK);
1025 GNUNET_CLIENT_notify_transmit_ready_cancel (h->cth);
1028 if (NULL != h->client)
1030 GNUNET_CLIENT_disconnect (h->client);
1033 /* Forget about all neighbours that we used to be connected to */
1034 GNUNET_CONTAINER_multipeermap_iterate (h->neighbours,
1035 &neighbour_delete, h);
1036 if (h->quota_task != GNUNET_SCHEDULER_NO_TASK)
1038 GNUNET_SCHEDULER_cancel (h->quota_task);
1039 h->quota_task = GNUNET_SCHEDULER_NO_TASK;
1041 while ((NULL != (th = h->control_head)))
1043 GNUNET_CONTAINER_DLL_remove (h->control_head, h->control_tail, th);
1044 th->notify (th->notify_cls, 0, NULL);
1047 LOG (GNUNET_ERROR_TYPE_DEBUG,
1048 "Scheduling task to reconnect to transport service in %s.\n",
1049 GNUNET_STRINGS_relative_time_to_string(h->reconnect_delay, GNUNET_YES));
1051 GNUNET_SCHEDULER_add_delayed (h->reconnect_delay, &reconnect, h);
1052 h->reconnect_delay = GNUNET_TIME_STD_BACKOFF (h->reconnect_delay);
1057 * Cancel control request for transmission to the transport service.
1059 * @param th handle to the transport service
1060 * @param tth transmit handle to cancel
1063 cancel_control_transmit (struct GNUNET_TRANSPORT_Handle *th,
1064 struct GNUNET_TRANSPORT_TransmitHandle *tth)
1066 LOG (GNUNET_ERROR_TYPE_DEBUG,
1067 "Canceling transmit of contral transmission requested\n");
1068 GNUNET_CONTAINER_DLL_remove (th->control_head, th->control_tail, tth);
1075 * Send REQUEST_CONNECT message to the service.
1077 * @param cls the `struct GNUNET_PeerIdentity`
1078 * @param size number of bytes available in @a buf
1079 * @param buf where to copy the message
1080 * @return number of bytes copied to @a buf
1083 send_try_connect (void *cls, size_t size, void *buf)
1085 struct GNUNET_TRANSPORT_TryConnectHandle *tch = cls;
1086 struct TransportRequestConnectMessage msg;
1090 if (NULL != tch->cb)
1091 tch->cb (tch->cb_cls, GNUNET_SYSERR);
1092 GNUNET_CONTAINER_DLL_remove (tch->th->tc_head, tch->th->tc_tail, tch);
1093 LOG (GNUNET_ERROR_TYPE_DEBUG,
1094 "Discarding `%s' request to `%4s' due to error in transport service connection.\n",
1096 GNUNET_i2s (&tch->pid));
1100 LOG (GNUNET_ERROR_TYPE_DEBUG,
1101 "Transmitting `%s' request with respect to `%4s'.\n",
1103 GNUNET_i2s (&tch->pid));
1104 GNUNET_assert (size >= sizeof (struct TransportRequestConnectMessage));
1105 msg.header.size = htons (sizeof (struct TransportRequestConnectMessage));
1106 msg.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_REQUEST_CONNECT);
1107 msg.reserved = htonl (0);
1108 msg.peer = tch->pid;
1109 memcpy (buf, &msg, sizeof (msg));
1110 if (NULL != tch->cb)
1111 tch->cb (tch->cb_cls, GNUNET_OK);
1112 GNUNET_CONTAINER_DLL_remove (tch->th->tc_head, tch->th->tc_tail, tch);
1114 return sizeof (struct TransportRequestConnectMessage);
1118 * Ask the transport service to establish a connection to
1121 * @param handle connection to transport service
1122 * @param target who we should try to connect to
1123 * @param cb callback to be called when request was transmitted to transport
1125 * @param cb_cls closure for the callback
1126 * @return a `struct GNUNET_TRANSPORT_TryConnectHandle` handle or
1127 * NULL on failure (cb will not be called)
1129 struct GNUNET_TRANSPORT_TryConnectHandle *
1130 GNUNET_TRANSPORT_try_connect (struct GNUNET_TRANSPORT_Handle *handle,
1131 const struct GNUNET_PeerIdentity *target,
1132 GNUNET_TRANSPORT_TryConnectCallback cb,
1135 struct GNUNET_TRANSPORT_TryConnectHandle *tch = NULL;
1137 if (NULL == handle->client)
1139 tch = GNUNET_new (struct GNUNET_TRANSPORT_TryConnectHandle);
1141 tch->pid = *(target);
1143 tch->cb_cls = cb_cls;
1144 tch->tth = schedule_control_transmit (handle,
1145 sizeof (struct TransportRequestConnectMessage),
1146 &send_try_connect, tch);
1147 GNUNET_CONTAINER_DLL_insert(handle->tc_head, handle->tc_tail, tch);
1153 * Cancel the request to transport to try a connect
1154 * Callback will not be called
1156 * @param tch the handle to cancel
1159 GNUNET_TRANSPORT_try_connect_cancel (struct GNUNET_TRANSPORT_TryConnectHandle *tch)
1161 struct GNUNET_TRANSPORT_Handle *th;
1164 cancel_control_transmit (th, tch->tth);
1165 GNUNET_CONTAINER_DLL_remove (th->tc_head, th->tc_tail, tch);
1170 * Send HELLO message to the service.
1172 * @param cls the HELLO message to send
1173 * @param size number of bytes available in @a buf
1174 * @param buf where to copy the message
1175 * @return number of bytes copied to @a buf
1178 send_hello (void *cls, size_t size, void *buf)
1180 struct GNUNET_TRANSPORT_OfferHelloHandle *ohh = cls;
1181 struct GNUNET_MessageHeader *msg = ohh->msg;
1183 struct GNUNET_SCHEDULER_TaskContext tc;
1185 tc.read_ready = NULL;
1186 tc.write_ready = NULL;
1187 tc.reason = GNUNET_SCHEDULER_REASON_TIMEOUT;
1190 LOG (GNUNET_ERROR_TYPE_DEBUG,
1191 "Timeout while trying to transmit `%s' request.\n",
1193 if (NULL != ohh->cont)
1194 ohh->cont (ohh->cls, &tc);
1196 GNUNET_CONTAINER_DLL_remove (ohh->th->oh_head, ohh->th->oh_tail, ohh);
1200 LOG (GNUNET_ERROR_TYPE_DEBUG,
1201 "Transmitting `%s' request.\n",
1203 ssize = ntohs (msg->size);
1204 GNUNET_assert (size >= ssize);
1205 memcpy (buf, msg, ssize);
1207 tc.reason = GNUNET_SCHEDULER_REASON_READ_READY;
1208 if (NULL != ohh->cont)
1209 ohh->cont (ohh->cls, &tc);
1210 GNUNET_CONTAINER_DLL_remove (ohh->th->oh_head, ohh->th->oh_tail, ohh);
1217 * Send traffic metric message to the service.
1219 * @param cls the message to send
1220 * @param size number of bytes available in @a buf
1221 * @param buf where to copy the message
1222 * @return number of bytes copied to @a buf
1225 send_metric (void *cls, size_t size, void *buf)
1227 struct TrafficMetricMessage *msg = cls;
1232 LOG (GNUNET_ERROR_TYPE_DEBUG,
1233 "Timeout while trying to transmit `%s' request.\n",
1238 LOG (GNUNET_ERROR_TYPE_DEBUG,
1239 "Transmitting `%s' request.\n",
1241 ssize = ntohs (msg->header.size);
1242 GNUNET_assert (size >= ssize);
1243 memcpy (buf, msg, ssize);
1250 * Set transport metrics for a peer and a direction
1252 * @param handle transport handle
1253 * @param peer the peer to set the metric for
1254 * @param inbound set inbound direction (#GNUNET_YES or #GNUNET_NO)
1255 * @param outbound set outbound direction (#GNUNET_YES or #GNUNET_NO)
1256 * @param ats the metric as ATS information
1257 * @param ats_count the number of metrics
1259 * Supported ATS values:
1260 * #GNUNET_ATS_QUALITY_NET_DELAY (value in ms)
1261 * #GNUNET_ATS_QUALITY_NET_DISTANCE (value in count(hops))
1264 * To enforce a delay of 10 ms for peer p1 in sending direction use:
1266 * struct GNUNET_ATS_Information ats;
1267 * ats.type = ntohl (GNUNET_ATS_QUALITY_NET_DELAY);
1268 * ats.value = ntohl (10);
1269 * GNUNET_TRANSPORT_set_traffic_metric (th, p1, TM_SEND, &ats, 1);
1272 * Delay restrictions in receiving direction will be enforced with
1276 GNUNET_TRANSPORT_set_traffic_metric (struct GNUNET_TRANSPORT_Handle *handle,
1277 const struct GNUNET_PeerIdentity *peer,
1280 const struct GNUNET_ATS_Information *ats,
1283 struct TrafficMetricMessage *msg;
1285 GNUNET_assert ((outbound == GNUNET_YES) || (outbound == GNUNET_NO));
1286 GNUNET_assert ((inbound == GNUNET_YES) || (inbound == GNUNET_NO));
1287 if ((GNUNET_NO == inbound) && (GNUNET_NO == outbound))
1292 size_t len = sizeof (struct TrafficMetricMessage) +
1293 ats_count * sizeof (struct GNUNET_ATS_Information);
1295 msg = GNUNET_malloc (len);
1296 msg->header.size = htons (len);
1297 msg->header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_TRAFFIC_METRIC);
1298 msg->direction = htons (0 + outbound + 2 * inbound);
1299 msg->ats_count = htons (ats_count);
1300 msg->peer = (*peer);
1301 memcpy (&msg[1], ats, ats_count * sizeof (struct GNUNET_ATS_Information));
1302 schedule_control_transmit (handle, len, &send_metric, msg);
1308 * Offer the transport service the HELLO of another peer. Note that
1309 * the transport service may just ignore this message if the HELLO is
1310 * malformed or useless due to our local configuration.
1312 * @param handle connection to transport service
1313 * @param hello the hello message
1314 * @param cont continuation to call when HELLO has been sent,
1315 * tc reason #GNUNET_SCHEDULER_REASON_TIMEOUT for fail
1316 * tc reasong #GNUNET_SCHEDULER_REASON_READ_READY for success
1317 * @param cls closure for continuation
1318 * @return a `struct GNUNET_TRANSPORT_OfferHelloHandle` handle or NULL on failure,
1319 * in case of failure cont will not be called
1322 struct GNUNET_TRANSPORT_OfferHelloHandle *
1323 GNUNET_TRANSPORT_offer_hello (struct GNUNET_TRANSPORT_Handle *handle,
1324 const struct GNUNET_MessageHeader *hello,
1325 GNUNET_SCHEDULER_Task cont, void *cls)
1327 struct GNUNET_TRANSPORT_OfferHelloHandle *ohh;
1328 struct GNUNET_MessageHeader *msg;
1329 struct GNUNET_PeerIdentity peer;
1332 if (NULL == handle->client)
1334 GNUNET_break (ntohs (hello->type) == GNUNET_MESSAGE_TYPE_HELLO);
1335 size = ntohs (hello->size);
1336 GNUNET_break (size >= sizeof (struct GNUNET_MessageHeader));
1338 GNUNET_HELLO_get_id ((const struct GNUNET_HELLO_Message *) hello, &peer))
1344 msg = GNUNET_malloc (size);
1345 memcpy (msg, hello, size);
1346 LOG (GNUNET_ERROR_TYPE_DEBUG,
1347 "Offering `%s' message of `%4s' to transport for validation.\n", "HELLO",
1348 GNUNET_i2s (&peer));
1350 ohh = GNUNET_new (struct GNUNET_TRANSPORT_OfferHelloHandle);
1355 ohh->tth = schedule_control_transmit (handle, size, &send_hello, ohh);
1356 GNUNET_CONTAINER_DLL_insert (handle->oh_head, handle->oh_tail, ohh);
1362 * Cancel the request to transport to offer the HELLO message
1364 * @param ohh the GNUNET_TRANSPORT_OfferHelloHandle to cancel
1367 GNUNET_TRANSPORT_offer_hello_cancel (struct GNUNET_TRANSPORT_OfferHelloHandle *ohh)
1369 struct GNUNET_TRANSPORT_Handle *th = ohh->th;
1371 cancel_control_transmit (ohh->th, ohh->tth);
1372 GNUNET_CONTAINER_DLL_remove (th->oh_head, th->oh_tail, ohh);
1373 GNUNET_free (ohh->msg);
1379 * Checks if a given peer is connected to us
1381 * @param handle connection to transport service
1382 * @param peer the peer to check
1383 * @return #GNUNET_YES (connected) or #GNUNET_NO (disconnected)
1386 GNUNET_TRANSPORT_check_peer_connected (struct GNUNET_TRANSPORT_Handle *handle,
1387 const struct GNUNET_PeerIdentity *peer)
1390 GNUNET_CONTAINER_multipeermap_contains (handle->neighbours,
1398 * Task to call the HelloUpdateCallback of the GetHelloHandle
1400 * @param cls the GetHelloHandle
1401 * @param tc the scheduler task context
1404 call_hello_update_cb_async (void *cls,
1405 const struct GNUNET_SCHEDULER_TaskContext *tc)
1407 struct GNUNET_TRANSPORT_GetHelloHandle *ghh = cls;
1409 GNUNET_assert (NULL != ghh->handle->my_hello);
1410 GNUNET_assert (GNUNET_SCHEDULER_NO_TASK != ghh->notify_task);
1411 ghh->notify_task = GNUNET_SCHEDULER_NO_TASK;
1412 ghh->rec (ghh->rec_cls,
1413 (const struct GNUNET_MessageHeader *) ghh->handle->my_hello);
1418 * Obtain the HELLO message for this peer. The callback given in this function
1419 * is never called synchronously.
1421 * @param handle connection to transport service
1422 * @param rec function to call with the HELLO, sender will be our peer
1423 * identity; message and sender will be NULL on timeout
1424 * (handshake with transport service pending/failed).
1425 * cost estimate will be 0.
1426 * @param rec_cls closure for @a rec
1427 * @return handle to cancel the operation
1429 struct GNUNET_TRANSPORT_GetHelloHandle *
1430 GNUNET_TRANSPORT_get_hello (struct GNUNET_TRANSPORT_Handle *handle,
1431 GNUNET_TRANSPORT_HelloUpdateCallback rec,
1434 struct GNUNET_TRANSPORT_GetHelloHandle *hwl;
1436 hwl = GNUNET_new (struct GNUNET_TRANSPORT_GetHelloHandle);
1438 hwl->rec_cls = rec_cls;
1439 hwl->handle = handle;
1440 GNUNET_CONTAINER_DLL_insert (handle->hwl_head, handle->hwl_tail, hwl);
1441 if (handle->my_hello != NULL)
1442 hwl->notify_task = GNUNET_SCHEDULER_add_now (&call_hello_update_cb_async,
1449 * Stop receiving updates about changes to our HELLO message.
1451 * @param ghh handle to cancel
1454 GNUNET_TRANSPORT_get_hello_cancel (struct GNUNET_TRANSPORT_GetHelloHandle *ghh)
1456 struct GNUNET_TRANSPORT_Handle *handle = ghh->handle;
1458 if (GNUNET_SCHEDULER_NO_TASK != ghh->notify_task)
1459 GNUNET_SCHEDULER_cancel (ghh->notify_task);
1460 GNUNET_CONTAINER_DLL_remove (handle->hwl_head, handle->hwl_tail, ghh);
1466 * Connect to the transport service. Note that the connection may
1467 * complete (or fail) asynchronously.
1469 * @param cfg configuration to use
1470 * @param self our own identity (API should check that it matches
1471 * the identity found by transport), or NULL (no check)
1472 * @param cls closure for the callbacks
1473 * @param rec receive function to call
1474 * @param nc function to call on connect events
1475 * @param nd function to call on disconnect events
1477 struct GNUNET_TRANSPORT_Handle *
1478 GNUNET_TRANSPORT_connect (const struct GNUNET_CONFIGURATION_Handle *cfg,
1479 const struct GNUNET_PeerIdentity *self, void *cls,
1480 GNUNET_TRANSPORT_ReceiveCallback rec,
1481 GNUNET_TRANSPORT_NotifyConnect nc,
1482 GNUNET_TRANSPORT_NotifyDisconnect nd)
1484 struct GNUNET_TRANSPORT_Handle *ret;
1486 ret = GNUNET_new (struct GNUNET_TRANSPORT_Handle);
1490 ret->check_self = GNUNET_YES;
1497 ret->reconnect_delay = GNUNET_TIME_UNIT_ZERO;
1498 LOG (GNUNET_ERROR_TYPE_DEBUG,
1499 "Connecting to transport service.\n");
1500 ret->client = GNUNET_CLIENT_connect ("transport", cfg);
1501 if (NULL == ret->client)
1507 GNUNET_CONTAINER_multipeermap_create (STARTING_NEIGHBOURS_SIZE,
1510 GNUNET_CONTAINER_heap_create (GNUNET_CONTAINER_HEAP_ORDER_MIN);
1511 schedule_control_transmit (ret, sizeof (struct StartMessage),
1518 * Disconnect from the transport service.
1520 * @param handle handle to the service as returned from GNUNET_TRANSPORT_connect
1523 GNUNET_TRANSPORT_disconnect (struct GNUNET_TRANSPORT_Handle *handle)
1525 LOG (GNUNET_ERROR_TYPE_DEBUG,
1526 "Transport disconnect called!\n");
1527 /* this disconnects all neighbours... */
1528 if (handle->reconnect_task == GNUNET_SCHEDULER_NO_TASK)
1529 disconnect_and_schedule_reconnect (handle);
1530 /* and now we stop trying to connect again... */
1531 if (handle->reconnect_task != GNUNET_SCHEDULER_NO_TASK)
1533 GNUNET_SCHEDULER_cancel (handle->reconnect_task);
1534 handle->reconnect_task = GNUNET_SCHEDULER_NO_TASK;
1536 GNUNET_CONTAINER_multipeermap_destroy (handle->neighbours);
1537 handle->neighbours = NULL;
1538 if (handle->quota_task != GNUNET_SCHEDULER_NO_TASK)
1540 GNUNET_SCHEDULER_cancel (handle->quota_task);
1541 handle->quota_task = GNUNET_SCHEDULER_NO_TASK;
1543 GNUNET_free_non_null (handle->my_hello);
1544 handle->my_hello = NULL;
1545 GNUNET_assert (handle->tc_head == NULL);
1546 GNUNET_assert (handle->tc_tail == NULL);
1547 GNUNET_assert (handle->hwl_head == NULL);
1548 GNUNET_assert (handle->hwl_tail == NULL);
1549 GNUNET_CONTAINER_heap_destroy (handle->ready_heap);
1550 handle->ready_heap = NULL;
1551 GNUNET_free (handle);
1556 * Check if we could queue a message of the given size for
1557 * transmission. The transport service will take both its
1558 * internal buffers and bandwidth limits imposed by the
1559 * other peer into consideration when answering this query.
1561 * @param handle connection to transport service
1562 * @param target who should receive the message
1563 * @param size how big is the message we want to transmit?
1564 * @param priority how important is the message?
1565 * @param timeout after how long should we give up (and call
1566 * notify with buf NULL and size 0)?
1567 * @param notify function to call when we are ready to
1568 * send such a message
1569 * @param notify_cls closure for @a notify
1570 * @return NULL if someone else is already waiting to be notified
1571 * non-NULL if the notify callback was queued (can be used to cancel
1572 * using #GNUNET_TRANSPORT_notify_transmit_ready_cancel)
1574 struct GNUNET_TRANSPORT_TransmitHandle *
1575 GNUNET_TRANSPORT_notify_transmit_ready (struct GNUNET_TRANSPORT_Handle *handle,
1576 const struct GNUNET_PeerIdentity *target,
1577 size_t size, uint32_t priority,
1578 struct GNUNET_TIME_Relative timeout,
1579 GNUNET_CONNECTION_TransmitReadyNotify notify,
1582 struct Neighbour *n;
1583 struct GNUNET_TRANSPORT_TransmitHandle *th;
1584 struct GNUNET_TIME_Relative delay;
1586 n = neighbour_find (handle, target);
1589 /* use GNUNET_TRANSPORT_try_connect first, only use this function
1590 * once a connection has been established */
1596 /* attempt to send two messages at the same time to the same peer */
1600 GNUNET_assert (NULL == n->hn);
1601 th = GNUNET_new (struct GNUNET_TRANSPORT_TransmitHandle);
1603 th->notify = notify;
1604 th->notify_cls = notify_cls;
1605 th->timeout = GNUNET_TIME_relative_to_absolute (timeout);
1606 th->notify_size = size;
1607 th->priority = priority;
1609 /* calculate when our transmission should be ready */
1610 delay = GNUNET_BANDWIDTH_tracker_get_delay (&n->out_tracker, size + n->traffic_overhead);
1611 n->traffic_overhead = 0;
1612 if (delay.rel_value_us > timeout.rel_value_us)
1613 delay.rel_value_us = 0; /* notify immediately (with failure) */
1614 LOG (GNUNET_ERROR_TYPE_DEBUG,
1615 "Bandwidth tracker allows next transmission to peer %s in %s\n",
1616 GNUNET_i2s (target),
1617 GNUNET_STRINGS_relative_time_to_string (delay, GNUNET_YES));
1618 n->hn = GNUNET_CONTAINER_heap_insert (handle->ready_heap, n, delay.rel_value_us);
1619 schedule_transmission (handle);
1625 * Cancel the specified transmission-ready notification.
1627 * @param th handle returned from #GNUNET_TRANSPORT_notify_transmit_ready()
1630 GNUNET_TRANSPORT_notify_transmit_ready_cancel (struct GNUNET_TRANSPORT_TransmitHandle *th)
1632 struct Neighbour *n;
1634 GNUNET_assert (NULL == th->next);
1635 GNUNET_assert (NULL == th->prev);
1637 GNUNET_assert (th == n->th);
1641 GNUNET_CONTAINER_heap_remove_node (n->hn);
1646 GNUNET_assert (GNUNET_SCHEDULER_NO_TASK != th->timeout_task);
1647 GNUNET_SCHEDULER_cancel (th->timeout_task);
1648 th->timeout_task = GNUNET_SCHEDULER_NO_TASK;
1654 /* end of transport_api.c */