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
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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_TRANSPORT_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?
98 * Entry in hash table of all of our current neighbours.
103 * Overall transport handle.
105 struct GNUNET_TRANSPORT_Handle *h;
108 * Active transmit handle or NULL.
110 struct GNUNET_TRANSPORT_TransmitHandle *th;
113 * Identity of this neighbour.
115 struct GNUNET_PeerIdentity id;
118 * Outbound bandwidh tracker.
120 struct GNUNET_BANDWIDTH_Tracker out_tracker;
123 * Entry in our readyness heap (which is sorted by 'next_ready'
124 * value). NULL if there is no pending transmission request for
125 * this neighbour or if we're waiting for 'is_ready' to become
126 * true AFTER the 'out_tracker' suggested that this peer's quota
127 * has been satisfied (so once 'is_ready' goes to GNUNET_YES,
128 * we should immediately go back into the heap).
130 struct GNUNET_CONTAINER_HeapNode *hn;
133 * Is this peer currently ready to receive a message?
138 * Sending consumed more bytes on wire than payload was announced
139 * This overhead is added to the delay of next sending operation
141 size_t traffic_overhead;
146 * Linked list of functions to call whenever our HELLO is updated.
148 struct GNUNET_TRANSPORT_GetHelloHandle
152 * This is a doubly linked list.
154 struct GNUNET_TRANSPORT_GetHelloHandle *next;
157 * This is a doubly linked list.
159 struct GNUNET_TRANSPORT_GetHelloHandle *prev;
164 struct GNUNET_TRANSPORT_Handle *handle;
167 * Callback to call once we got our HELLO.
169 GNUNET_TRANSPORT_HelloUpdateCallback rec;
172 * Task for calling the HelloUpdateCallback when we already have a HELLO
174 GNUNET_SCHEDULER_TaskIdentifier notify_task;
177 * Closure for @e rec.
184 * Linked list for all try-connect requests
186 struct GNUNET_TRANSPORT_TryConnectHandle
191 struct GNUNET_TRANSPORT_TryConnectHandle *prev;
196 struct GNUNET_TRANSPORT_TryConnectHandle *next;
198 struct GNUNET_PeerIdentity pid;
200 struct GNUNET_TRANSPORT_Handle *th;
202 struct GNUNET_TRANSPORT_TransmitHandle *tth;
204 GNUNET_TRANSPORT_TryConnectCallback cb;
214 * Linked list for all try-connect requests
216 struct GNUNET_TRANSPORT_OfferHelloHandle
221 struct GNUNET_TRANSPORT_OfferHelloHandle *prev;
226 struct GNUNET_TRANSPORT_OfferHelloHandle *next;
228 struct GNUNET_TRANSPORT_Handle *th;
230 struct GNUNET_TRANSPORT_TransmitHandle *tth;
232 GNUNET_SCHEDULER_Task cont;
235 * Closure for @e cont
239 struct GNUNET_MessageHeader *msg;
244 * Handle for the transport service (includes all of the
245 * state for the transport service).
247 struct GNUNET_TRANSPORT_Handle
251 * Closure for the callbacks.
256 * Function to call for received data.
258 GNUNET_TRANSPORT_ReceiveCallback rec;
261 * function to call on connect events
263 GNUNET_TRANSPORT_NotifyConnect nc_cb;
266 * function to call on disconnect events
268 GNUNET_TRANSPORT_NotifyDisconnect nd_cb;
271 * function to call on excess bandwidth events
273 GNUNET_TRANSPORT_NotifyExcessBandwidth neb_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);
424 outbound_bw_tracker_update (void *cls)
426 struct Neighbour *n = cls;
427 struct GNUNET_TIME_Relative delay;
431 delay = GNUNET_BANDWIDTH_tracker_get_delay (&n->out_tracker,
432 n->th->notify_size + n->traffic_overhead);
433 LOG(GNUNET_ERROR_TYPE_DEBUG,
434 "New outbound delay %llu us\n",delay.rel_value_us);
435 GNUNET_CONTAINER_heap_update_cost (n->h->ready_heap,
436 n->hn, delay.rel_value_us);
437 schedule_transmission (n->h);
442 * Function called by the bandwidth tracker if we have excess
445 * @param cls the `struct Neighbour` that has excess bandwidth
448 notify_excess_cb (void *cls)
450 struct Neighbour *n = cls;
451 struct GNUNET_TRANSPORT_Handle *h = n->h;
453 if (NULL != h->neb_cb)
460 * Add neighbour to our list
462 * @return NULL if this API is currently disconnecting from the service
464 static struct Neighbour *
465 neighbour_add (struct GNUNET_TRANSPORT_Handle *h,
466 const struct GNUNET_PeerIdentity *pid)
470 LOG (GNUNET_ERROR_TYPE_DEBUG,
471 "Creating entry for neighbour `%4s'.\n",
473 n = GNUNET_new (struct Neighbour);
476 n->is_ready = GNUNET_YES;
477 n->traffic_overhead = 0;
478 GNUNET_BANDWIDTH_tracker_init2 (&n->out_tracker,
479 &outbound_bw_tracker_update, n,
480 GNUNET_CONSTANTS_DEFAULT_BW_IN_OUT,
481 MAX_BANDWIDTH_CARRY_S,
484 GNUNET_assert (GNUNET_OK ==
485 GNUNET_CONTAINER_multipeermap_put (h->neighbours,
487 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
493 * Iterator over hash map entries, for deleting state of a neighbour.
495 * @param cls the `struct GNUNET_TRANSPORT_Handle *`
496 * @param key peer identity
497 * @param value value in the hash map, the neighbour entry to delete
498 * @return #GNUNET_YES if we should continue to
503 neighbour_delete (void *cls,
504 const struct GNUNET_PeerIdentity *key, void *value)
506 struct GNUNET_TRANSPORT_Handle *handle = cls;
507 struct Neighbour *n = value;
509 if (NULL != handle->nd_cb)
510 handle->nd_cb (handle->cls, &n->id);
511 GNUNET_assert (NULL == n->th);
512 GNUNET_assert (NULL == n->hn);
513 GNUNET_assert (GNUNET_YES ==
514 GNUNET_CONTAINER_multipeermap_remove (handle->neighbours, key,
520 static int reconnecting;
523 * Function we use for handling incoming messages.
525 * @param cls closure, a `struct GNUNET_TRANSPORT_Handle *`
526 * @param msg message received, NULL on timeout or fatal error
529 demultiplexer (void *cls, const struct GNUNET_MessageHeader *msg)
531 struct GNUNET_TRANSPORT_Handle *h = cls;
532 const struct DisconnectInfoMessage *dim;
533 const struct ConnectInfoMessage *cim;
534 const struct InboundMessage *im;
535 const struct GNUNET_MessageHeader *imm;
536 const struct SendOkMessage *okm;
537 const struct QuotaSetMessage *qm;
538 struct GNUNET_TRANSPORT_GetHelloHandle *hwl;
539 struct GNUNET_TRANSPORT_GetHelloHandle *next_hwl;
541 struct GNUNET_PeerIdentity me;
544 uint32_t bytes_physical;
546 GNUNET_assert (NULL != h->client);
547 if (GNUNET_YES == reconnecting)
553 LOG (GNUNET_ERROR_TYPE_DEBUG,
554 "Error receiving from transport service, disconnecting temporarily.\n");
555 reconnecting = GNUNET_YES;
556 disconnect_and_schedule_reconnect (h);
559 GNUNET_CLIENT_receive (h->client, &demultiplexer, h,
560 GNUNET_TIME_UNIT_FOREVER_REL);
561 size = ntohs (msg->size);
562 switch (ntohs (msg->type))
564 case GNUNET_MESSAGE_TYPE_HELLO:
566 GNUNET_HELLO_get_id ((const struct GNUNET_HELLO_Message *) msg, &me))
571 LOG (GNUNET_ERROR_TYPE_DEBUG,
572 "Receiving (my own) `%s' message, I am `%4s'.\n", "HELLO",
574 GNUNET_free_non_null (h->my_hello);
576 if (size < sizeof (struct GNUNET_MessageHeader))
581 h->my_hello = GNUNET_malloc (size);
582 memcpy (h->my_hello, msg, size);
586 next_hwl = hwl->next;
587 hwl->rec (hwl->rec_cls,
588 (const struct GNUNET_MessageHeader *) h->my_hello);
592 case GNUNET_MESSAGE_TYPE_TRANSPORT_CONNECT:
593 if (size < sizeof (struct ConnectInfoMessage))
598 cim = (const struct ConnectInfoMessage *) msg;
600 sizeof (struct ConnectInfoMessage))
605 LOG (GNUNET_ERROR_TYPE_DEBUG,
606 "Receiving `%s' message for `%4s'.\n",
607 "CONNECT", GNUNET_i2s (&cim->id));
608 n = neighbour_find (h, &cim->id);
614 n = neighbour_add (h, &cim->id);
615 LOG (GNUNET_ERROR_TYPE_DEBUG,
616 "Receiving `%s' message for `%4s' with quota %u\n",
618 GNUNET_i2s (&cim->id),
619 ntohl (cim->quota_out.value__));
620 GNUNET_BANDWIDTH_tracker_update_quota (&n->out_tracker, cim->quota_out);
621 if (h->nc_cb != NULL)
622 h->nc_cb (h->cls, &n->id);
624 case GNUNET_MESSAGE_TYPE_TRANSPORT_DISCONNECT:
625 if (size != sizeof (struct DisconnectInfoMessage))
630 dim = (const struct DisconnectInfoMessage *) msg;
631 GNUNET_break (ntohl (dim->reserved) == 0);
632 LOG (GNUNET_ERROR_TYPE_DEBUG,
633 "Receiving `%s' message for `%4s'.\n",
634 "DISCONNECT", GNUNET_i2s (&dim->peer));
635 n = neighbour_find (h, &dim->peer);
641 neighbour_delete (h, &dim->peer, n);
643 case GNUNET_MESSAGE_TYPE_TRANSPORT_SEND_OK:
644 if (size != sizeof (struct SendOkMessage))
649 okm = (const struct SendOkMessage *) msg;
650 bytes_msg = ntohl (okm->bytes_msg);
651 bytes_physical = ntohl (okm->bytes_physical);
652 LOG (GNUNET_ERROR_TYPE_DEBUG,
653 "Receiving SEND_OK message, transmission %s.\n",
654 ntohl (okm->success) == GNUNET_OK ? "succeeded" : "failed");
656 n = neighbour_find (h, &okm->peer);
660 if (bytes_physical >= bytes_msg)
662 LOG (GNUNET_ERROR_TYPE_DEBUG,
663 "Overhead for %u byte message: %u\n",
664 bytes_msg, bytes_physical - bytes_msg);
665 n->traffic_overhead += bytes_physical - bytes_msg;
667 GNUNET_break (GNUNET_NO == n->is_ready);
668 n->is_ready = GNUNET_YES;
669 if ((NULL != n->th) && (NULL == n->hn))
671 GNUNET_assert (GNUNET_SCHEDULER_NO_TASK != n->th->timeout_task);
672 GNUNET_SCHEDULER_cancel (n->th->timeout_task);
673 n->th->timeout_task = GNUNET_SCHEDULER_NO_TASK;
674 /* we've been waiting for this (congestion, not quota,
675 * caused delayed transmission) */
676 n->hn = GNUNET_CONTAINER_heap_insert (h->ready_heap, n, 0);
677 schedule_transmission (h);
680 case GNUNET_MESSAGE_TYPE_TRANSPORT_RECV:
681 LOG (GNUNET_ERROR_TYPE_DEBUG,
682 "Receiving `%s' message.\n",
685 sizeof (struct InboundMessage) + sizeof (struct GNUNET_MessageHeader))
690 im = (const struct InboundMessage *) msg;
691 imm = (const struct GNUNET_MessageHeader *) &im[1];
692 if (ntohs (imm->size) + sizeof (struct InboundMessage) != size)
697 LOG (GNUNET_ERROR_TYPE_DEBUG,
698 "Received message of type %u from `%4s'.\n",
699 ntohs (imm->type), GNUNET_i2s (&im->peer));
700 n = neighbour_find (h, &im->peer);
707 h->rec (h->cls, &im->peer, imm);
709 case GNUNET_MESSAGE_TYPE_TRANSPORT_SET_QUOTA:
710 LOG (GNUNET_ERROR_TYPE_DEBUG,
711 "Receiving `%s' message.\n", "SET_QUOTA");
712 if (size != sizeof (struct QuotaSetMessage))
717 qm = (const struct QuotaSetMessage *) msg;
718 n = neighbour_find (h, &qm->peer);
721 LOG (GNUNET_ERROR_TYPE_DEBUG,
722 "Receiving `%s' message for `%4s' with quota %u\n",
724 GNUNET_i2s (&qm->peer),
725 ntohl (qm->quota.value__));
726 GNUNET_BANDWIDTH_tracker_update_quota (&n->out_tracker, qm->quota);
729 LOG (GNUNET_ERROR_TYPE_ERROR,
730 _("Received unexpected message of type %u in %s:%u\n"),
731 ntohs (msg->type), __FILE__, __LINE__);
739 * A transmission request could not be satisfied because of
740 * network congestion. Notify the initiator and clean up.
742 * @param cls the `struct GNUNET_TRANSPORT_TransmitHandle`
743 * @param tc scheduler context
746 timeout_request_due_to_congestion (void *cls,
747 const struct GNUNET_SCHEDULER_TaskContext *tc)
749 struct GNUNET_TRANSPORT_TransmitHandle *th = cls;
750 struct Neighbour *n = th->neighbour;
752 n->th->timeout_task = GNUNET_SCHEDULER_NO_TASK;
753 GNUNET_assert (th == n->th);
754 GNUNET_assert (NULL == n->hn);
756 th->notify (th->notify_cls, 0, NULL);
762 * Transmit message(s) to service.
764 * @param cls handle to transport
765 * @param size number of bytes available in @a buf
766 * @param buf where to copy the message
767 * @return number of bytes copied to @a buf
770 transport_notify_ready (void *cls, size_t size, void *buf)
772 struct GNUNET_TRANSPORT_Handle *h = cls;
773 struct GNUNET_TRANSPORT_TransmitHandle *th;
776 struct OutboundMessage obm;
781 GNUNET_assert (NULL != h->client);
785 /* transmission failed */
786 disconnect_and_schedule_reconnect (h);
792 /* first send control messages */
793 while ((NULL != (th = h->control_head)) && (th->notify_size <= size))
795 GNUNET_CONTAINER_DLL_remove (h->control_head, h->control_tail, th);
796 nret = th->notify (th->notify_cls, size, &cbuf[ret]);
797 LOG (GNUNET_ERROR_TYPE_DEBUG,
798 "Added %u bytes of control message at %u\n",
805 /* then, if possible and no control messages pending, send data messages */
806 while ((NULL == h->control_head) &&
807 (NULL != (n = GNUNET_CONTAINER_heap_peek (h->ready_heap))))
809 if (GNUNET_YES != n->is_ready)
811 /* peer not ready, wait for notification! */
812 GNUNET_assert (n == GNUNET_CONTAINER_heap_remove_root (h->ready_heap));
814 GNUNET_assert (GNUNET_SCHEDULER_NO_TASK == n->th->timeout_task);
815 n->th->timeout_task =
816 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_absolute_get_remaining
818 &timeout_request_due_to_congestion,
823 if (th->notify_size + sizeof (struct OutboundMessage) > size)
824 break; /* does not fit */
825 if (GNUNET_BANDWIDTH_tracker_get_delay
826 (&n->out_tracker, th->notify_size).rel_value_us > 0)
827 break; /* too early */
828 GNUNET_assert (n == GNUNET_CONTAINER_heap_remove_root (h->ready_heap));
831 n->is_ready = GNUNET_NO;
832 GNUNET_assert (size >= sizeof (struct OutboundMessage));
834 th->notify (th->notify_cls, size - sizeof (struct OutboundMessage),
835 &cbuf[ret + sizeof (struct OutboundMessage)]);
836 GNUNET_assert (mret <= size - sizeof (struct OutboundMessage));
839 GNUNET_assert (mret + sizeof (struct OutboundMessage) <
840 GNUNET_SERVER_MAX_MESSAGE_SIZE);
841 obm.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SEND);
842 obm.header.size = htons (mret + sizeof (struct OutboundMessage));
843 obm.reserved = htonl (0);
845 GNUNET_TIME_relative_hton (GNUNET_TIME_absolute_get_remaining
848 memcpy (&cbuf[ret], &obm, sizeof (struct OutboundMessage));
849 ret += (mret + sizeof (struct OutboundMessage));
850 size -= (mret + sizeof (struct OutboundMessage));
851 GNUNET_BANDWIDTH_tracker_consume (&n->out_tracker, mret);
855 /* if there are more pending messages, try to schedule those */
856 schedule_transmission (h);
857 LOG (GNUNET_ERROR_TYPE_DEBUG,
858 "Transmitting %u bytes to transport service\n",
865 * Schedule the task to send one message, either from the control
866 * list or the peer message queues to the service.
868 * @param cls transport service to schedule a transmission for
869 * @param tc scheduler context
872 schedule_transmission_task (void *cls,
873 const struct GNUNET_SCHEDULER_TaskContext *tc)
875 struct GNUNET_TRANSPORT_Handle *h = cls;
877 struct GNUNET_TRANSPORT_TransmitHandle *th;
880 h->quota_task = GNUNET_SCHEDULER_NO_TASK;
881 GNUNET_assert (NULL != h->client);
882 /* destroy all requests that have timed out */
883 while ((NULL != (n = GNUNET_CONTAINER_heap_peek (h->ready_heap))) &&
884 (0 == GNUNET_TIME_absolute_get_remaining (n->th->timeout).rel_value_us))
886 /* notify client that the request could not be satisfied within
887 * the given time constraints */
890 GNUNET_assert (n == GNUNET_CONTAINER_heap_remove_root (h->ready_heap));
892 LOG (GNUNET_ERROR_TYPE_DEBUG,
893 "Signalling timeout for transmission to peer %s due to congestion\n",
894 GNUNET_i2s (&n->id));
895 GNUNET_assert (0 == th->notify (th->notify_cls, 0, NULL));
900 if (NULL != h->control_head)
902 size = h->control_head->notify_size;
906 n = GNUNET_CONTAINER_heap_peek (h->ready_heap);
908 return; /* no pending messages */
909 size = n->th->notify_size + sizeof (struct OutboundMessage);
911 LOG (GNUNET_ERROR_TYPE_DEBUG,
912 "Calling notify_transmit_ready\n");
914 GNUNET_CLIENT_notify_transmit_ready (h->client, size,
915 GNUNET_TIME_UNIT_FOREVER_REL,
916 GNUNET_NO, &transport_notify_ready,
918 GNUNET_assert (NULL != h->cth);
923 * Schedule the task to send one message, either from the control
924 * list or the peer message queues to the service.
926 * @param h transport service to schedule a transmission for
929 schedule_transmission (struct GNUNET_TRANSPORT_Handle *h)
931 struct GNUNET_TIME_Relative delay;
934 GNUNET_assert (NULL != h->client);
935 if (h->quota_task != GNUNET_SCHEDULER_NO_TASK)
937 GNUNET_SCHEDULER_cancel (h->quota_task);
938 h->quota_task = GNUNET_SCHEDULER_NO_TASK;
940 if (NULL != h->control_head)
941 delay = GNUNET_TIME_UNIT_ZERO;
942 else if (NULL != (n = GNUNET_CONTAINER_heap_peek (h->ready_heap)))
945 GNUNET_BANDWIDTH_tracker_get_delay (&n->out_tracker,
946 n->th->notify_size + n->traffic_overhead);
947 n->traffic_overhead = 0;
950 return; /* no work to be done */
951 LOG (GNUNET_ERROR_TYPE_DEBUG,
952 "Scheduling next transmission to service in %s\n",
953 GNUNET_STRINGS_relative_time_to_string (delay, GNUNET_YES));
955 GNUNET_SCHEDULER_add_delayed (delay, &schedule_transmission_task, h);
960 * Queue control request for transmission to the transport
963 * @param h handle to the transport service
964 * @param size number of bytes to be transmitted
965 * @param notify function to call to get the content
966 * @param notify_cls closure for @a notify
967 * @return a `struct GNUNET_TRANSPORT_TransmitHandle`
969 static struct GNUNET_TRANSPORT_TransmitHandle *
970 schedule_control_transmit (struct GNUNET_TRANSPORT_Handle *h, size_t size,
971 GNUNET_TRANSPORT_TransmitReadyNotify notify,
974 struct GNUNET_TRANSPORT_TransmitHandle *th;
976 LOG (GNUNET_ERROR_TYPE_DEBUG,
977 "Control transmit of %u bytes requested\n",
979 th = GNUNET_new (struct GNUNET_TRANSPORT_TransmitHandle);
981 th->notify_cls = notify_cls;
982 th->notify_size = size;
983 GNUNET_CONTAINER_DLL_insert_tail (h->control_head, h->control_tail, th);
984 schedule_transmission (h);
990 * Transmit START message to service.
993 * @param size number of bytes available in @a buf
994 * @param buf where to copy the message
995 * @return number of bytes copied to @a buf
998 send_start (void *cls, size_t size, void *buf)
1000 struct GNUNET_TRANSPORT_Handle *h = cls;
1001 struct StartMessage s;
1006 /* Can only be shutdown, just give up */
1007 LOG (GNUNET_ERROR_TYPE_DEBUG,
1008 "Shutdown while trying to transmit `%s' request.\n",
1012 LOG (GNUNET_ERROR_TYPE_DEBUG,
1013 "Transmitting `%s' request.\n",
1015 GNUNET_assert (size >= sizeof (struct StartMessage));
1016 s.header.size = htons (sizeof (struct StartMessage));
1017 s.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_START);
1023 s.options = htonl (options);
1025 memcpy (buf, &s, sizeof (struct StartMessage));
1026 GNUNET_CLIENT_receive (h->client, &demultiplexer, h,
1027 GNUNET_TIME_UNIT_FOREVER_REL);
1028 return sizeof (struct StartMessage);
1033 * Try again to connect to transport service.
1035 * @param cls the handle to the transport service
1036 * @param tc scheduler context
1039 reconnect (void *cls,
1040 const struct GNUNET_SCHEDULER_TaskContext *tc)
1042 struct GNUNET_TRANSPORT_Handle *h = cls;
1044 h->reconnect_task = GNUNET_SCHEDULER_NO_TASK;
1045 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1047 /* shutdown, just give up */
1050 LOG (GNUNET_ERROR_TYPE_DEBUG,
1051 "Connecting to transport service.\n");
1052 GNUNET_assert (NULL == h->client);
1053 GNUNET_assert (NULL == h->control_head);
1054 GNUNET_assert (NULL == h->control_tail);
1055 reconnecting = GNUNET_NO;
1056 h->client = GNUNET_CLIENT_connect ("transport", h->cfg);
1058 GNUNET_assert (NULL != h->client);
1059 schedule_control_transmit (h, sizeof (struct StartMessage),
1065 * Function that will schedule the job that will try
1066 * to connect us again to the client.
1068 * @param h transport service to reconnect
1071 disconnect_and_schedule_reconnect (struct GNUNET_TRANSPORT_Handle *h)
1073 struct GNUNET_TRANSPORT_TransmitHandle *th;
1075 GNUNET_assert (h->reconnect_task == GNUNET_SCHEDULER_NO_TASK);
1078 GNUNET_CLIENT_notify_transmit_ready_cancel (h->cth);
1081 if (NULL != h->client)
1083 GNUNET_CLIENT_disconnect (h->client);
1085 /* LOG (GNUNET_ERROR_TYPE_ERROR,
1086 "Client disconnect done \n");*/
1088 /* Forget about all neighbours that we used to be connected to */
1089 GNUNET_CONTAINER_multipeermap_iterate (h->neighbours,
1090 &neighbour_delete, h);
1091 if (h->quota_task != GNUNET_SCHEDULER_NO_TASK)
1093 GNUNET_SCHEDULER_cancel (h->quota_task);
1094 h->quota_task = GNUNET_SCHEDULER_NO_TASK;
1096 while ((NULL != (th = h->control_head)))
1098 GNUNET_CONTAINER_DLL_remove (h->control_head, h->control_tail, th);
1099 th->notify (th->notify_cls, 0, NULL);
1102 LOG (GNUNET_ERROR_TYPE_DEBUG,
1103 "Scheduling task to reconnect to transport service in %s.\n",
1104 GNUNET_STRINGS_relative_time_to_string(h->reconnect_delay, GNUNET_YES));
1106 GNUNET_SCHEDULER_add_delayed (h->reconnect_delay, &reconnect, h);
1107 h->reconnect_delay = GNUNET_TIME_STD_BACKOFF (h->reconnect_delay);
1112 * Cancel control request for transmission to the transport service.
1114 * @param th handle to the transport service
1115 * @param tth transmit handle to cancel
1118 cancel_control_transmit (struct GNUNET_TRANSPORT_Handle *th,
1119 struct GNUNET_TRANSPORT_TransmitHandle *tth)
1121 LOG (GNUNET_ERROR_TYPE_DEBUG,
1122 "Canceling transmit of contral transmission requested\n");
1123 GNUNET_CONTAINER_DLL_remove (th->control_head, th->control_tail, tth);
1130 * Send REQUEST_CONNECT message to the service.
1132 * @param cls the `struct GNUNET_PeerIdentity`
1133 * @param size number of bytes available in @a buf
1134 * @param buf where to copy the message
1135 * @return number of bytes copied to @a buf
1138 send_try_connect (void *cls, size_t size, void *buf)
1140 struct GNUNET_TRANSPORT_TryConnectHandle *tch = cls;
1141 struct TransportRequestConnectMessage msg;
1145 if (NULL != tch->cb)
1146 tch->cb (tch->cb_cls, GNUNET_SYSERR);
1147 GNUNET_CONTAINER_DLL_remove (tch->th->tc_head, tch->th->tc_tail, tch);
1148 LOG (GNUNET_ERROR_TYPE_DEBUG,
1149 "Discarding `%s' request to `%4s' due to error in transport service connection.\n",
1151 GNUNET_i2s (&tch->pid));
1155 LOG (GNUNET_ERROR_TYPE_DEBUG,
1156 "Transmitting `%s' request with respect to `%4s'.\n",
1158 GNUNET_i2s (&tch->pid));
1159 GNUNET_assert (size >= sizeof (struct TransportRequestConnectMessage));
1160 msg.header.size = htons (sizeof (struct TransportRequestConnectMessage));
1161 msg.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_REQUEST_CONNECT);
1162 msg.reserved = htonl (0);
1163 msg.peer = tch->pid;
1164 memcpy (buf, &msg, sizeof (msg));
1165 if (NULL != tch->cb)
1166 tch->cb (tch->cb_cls, GNUNET_OK);
1167 GNUNET_CONTAINER_DLL_remove (tch->th->tc_head, tch->th->tc_tail, tch);
1169 return sizeof (struct TransportRequestConnectMessage);
1173 * Ask the transport service to establish a connection to
1176 * @param handle connection to transport service
1177 * @param target who we should try to connect to
1178 * @param cb callback to be called when request was transmitted to transport
1180 * @param cb_cls closure for the callback
1181 * @return a `struct GNUNET_TRANSPORT_TryConnectHandle` handle or
1182 * NULL on failure (cb will not be called)
1184 struct GNUNET_TRANSPORT_TryConnectHandle *
1185 GNUNET_TRANSPORT_try_connect (struct GNUNET_TRANSPORT_Handle *handle,
1186 const struct GNUNET_PeerIdentity *target,
1187 GNUNET_TRANSPORT_TryConnectCallback cb,
1190 struct GNUNET_TRANSPORT_TryConnectHandle *tch = NULL;
1192 if (NULL == handle->client)
1194 tch = GNUNET_new (struct GNUNET_TRANSPORT_TryConnectHandle);
1196 tch->pid = *(target);
1198 tch->cb_cls = cb_cls;
1199 tch->tth = schedule_control_transmit (handle,
1200 sizeof (struct TransportRequestConnectMessage),
1201 &send_try_connect, tch);
1202 GNUNET_CONTAINER_DLL_insert(handle->tc_head, handle->tc_tail, tch);
1208 * Cancel the request to transport to try a connect
1209 * Callback will not be called
1211 * @param tch the handle to cancel
1214 GNUNET_TRANSPORT_try_connect_cancel (struct GNUNET_TRANSPORT_TryConnectHandle *tch)
1216 struct GNUNET_TRANSPORT_Handle *th;
1219 cancel_control_transmit (th, tch->tth);
1220 GNUNET_CONTAINER_DLL_remove (th->tc_head, th->tc_tail, tch);
1225 * Send HELLO message to the service.
1227 * @param cls the HELLO message to send
1228 * @param size number of bytes available in @a buf
1229 * @param buf where to copy the message
1230 * @return number of bytes copied to @a buf
1233 send_hello (void *cls, size_t size, void *buf)
1235 struct GNUNET_TRANSPORT_OfferHelloHandle *ohh = cls;
1236 struct GNUNET_MessageHeader *msg = ohh->msg;
1238 struct GNUNET_SCHEDULER_TaskContext tc;
1240 tc.read_ready = NULL;
1241 tc.write_ready = NULL;
1242 tc.reason = GNUNET_SCHEDULER_REASON_TIMEOUT;
1245 LOG (GNUNET_ERROR_TYPE_DEBUG,
1246 "Timeout while trying to transmit `%s' request.\n",
1248 if (NULL != ohh->cont)
1249 ohh->cont (ohh->cls, &tc);
1251 GNUNET_CONTAINER_DLL_remove (ohh->th->oh_head, ohh->th->oh_tail, ohh);
1255 LOG (GNUNET_ERROR_TYPE_DEBUG,
1256 "Transmitting `%s' request.\n",
1258 ssize = ntohs (msg->size);
1259 GNUNET_assert (size >= ssize);
1260 memcpy (buf, msg, ssize);
1262 tc.reason = GNUNET_SCHEDULER_REASON_READ_READY;
1263 if (NULL != ohh->cont)
1264 ohh->cont (ohh->cls, &tc);
1265 GNUNET_CONTAINER_DLL_remove (ohh->th->oh_head, ohh->th->oh_tail, ohh);
1272 * Send traffic metric message to the service.
1274 * @param cls the message to send
1275 * @param size number of bytes available in @a buf
1276 * @param buf where to copy the message
1277 * @return number of bytes copied to @a buf
1280 send_metric (void *cls, size_t size, void *buf)
1282 struct TrafficMetricMessage *msg = cls;
1287 LOG (GNUNET_ERROR_TYPE_DEBUG,
1288 "Timeout while trying to transmit `%s' request.\n",
1293 LOG (GNUNET_ERROR_TYPE_DEBUG,
1294 "Transmitting `%s' request.\n",
1296 ssize = ntohs (msg->header.size);
1297 GNUNET_assert (size >= ssize);
1298 memcpy (buf, msg, ssize);
1305 * Set transport metrics for a peer and a direction
1307 * @param handle transport handle
1308 * @param peer the peer to set the metric for
1309 * @param inbound set inbound direction (#GNUNET_YES or #GNUNET_NO)
1310 * @param outbound set outbound direction (#GNUNET_YES or #GNUNET_NO)
1311 * @param ats the metric as ATS information
1312 * @param ats_count the number of metrics
1314 * Supported ATS values:
1315 * #GNUNET_ATS_QUALITY_NET_DELAY (value in ms)
1316 * #GNUNET_ATS_QUALITY_NET_DISTANCE (value in count(hops))
1319 * To enforce a delay of 10 ms for peer p1 in sending direction use:
1321 * struct GNUNET_ATS_Information ats;
1322 * ats.type = ntohl (GNUNET_ATS_QUALITY_NET_DELAY);
1323 * ats.value = ntohl (10);
1324 * GNUNET_TRANSPORT_set_traffic_metric (th, p1, TM_SEND, &ats, 1);
1327 * Delay restrictions in receiving direction will be enforced with
1331 GNUNET_TRANSPORT_set_traffic_metric (struct GNUNET_TRANSPORT_Handle *handle,
1332 const struct GNUNET_PeerIdentity *peer,
1335 const struct GNUNET_ATS_Information *ats,
1338 struct TrafficMetricMessage *msg;
1340 GNUNET_assert ((outbound == GNUNET_YES) || (outbound == GNUNET_NO));
1341 GNUNET_assert ((inbound == GNUNET_YES) || (inbound == GNUNET_NO));
1342 if ((GNUNET_NO == inbound) && (GNUNET_NO == outbound))
1347 size_t len = sizeof (struct TrafficMetricMessage) +
1348 ats_count * sizeof (struct GNUNET_ATS_Information);
1350 msg = GNUNET_malloc (len);
1351 msg->header.size = htons (len);
1352 msg->header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_TRAFFIC_METRIC);
1353 msg->direction = htons (0 + outbound + 2 * inbound);
1354 msg->ats_count = htons (ats_count);
1355 msg->peer = (*peer);
1356 memcpy (&msg[1], ats, ats_count * sizeof (struct GNUNET_ATS_Information));
1357 schedule_control_transmit (handle, len,
1364 * Offer the transport service the HELLO of another peer. Note that
1365 * the transport service may just ignore this message if the HELLO is
1366 * malformed or useless due to our local configuration.
1368 * @param handle connection to transport service
1369 * @param hello the hello message
1370 * @param cont continuation to call when HELLO has been sent,
1371 * tc reason #GNUNET_SCHEDULER_REASON_TIMEOUT for fail
1372 * tc reasong #GNUNET_SCHEDULER_REASON_READ_READY for success
1373 * @param cls closure for continuation
1374 * @return a `struct GNUNET_TRANSPORT_OfferHelloHandle` handle or NULL on failure,
1375 * in case of failure cont will not be called
1378 struct GNUNET_TRANSPORT_OfferHelloHandle *
1379 GNUNET_TRANSPORT_offer_hello (struct GNUNET_TRANSPORT_Handle *handle,
1380 const struct GNUNET_MessageHeader *hello,
1381 GNUNET_SCHEDULER_Task cont, void *cls)
1383 struct GNUNET_TRANSPORT_OfferHelloHandle *ohh;
1384 struct GNUNET_MessageHeader *msg;
1385 struct GNUNET_PeerIdentity peer;
1388 if (NULL == handle->client)
1390 GNUNET_break (ntohs (hello->type) == GNUNET_MESSAGE_TYPE_HELLO);
1391 size = ntohs (hello->size);
1392 GNUNET_break (size >= sizeof (struct GNUNET_MessageHeader));
1394 GNUNET_HELLO_get_id ((const struct GNUNET_HELLO_Message *) hello, &peer))
1400 msg = GNUNET_malloc (size);
1401 memcpy (msg, hello, size);
1402 LOG (GNUNET_ERROR_TYPE_DEBUG,
1403 "Offering `%s' message of `%4s' to transport for validation.\n", "HELLO",
1404 GNUNET_i2s (&peer));
1406 ohh = GNUNET_new (struct GNUNET_TRANSPORT_OfferHelloHandle);
1411 ohh->tth = schedule_control_transmit (handle, size,
1413 GNUNET_CONTAINER_DLL_insert (handle->oh_head, handle->oh_tail, ohh);
1419 * Cancel the request to transport to offer the HELLO message
1421 * @param ohh the GNUNET_TRANSPORT_OfferHelloHandle to cancel
1424 GNUNET_TRANSPORT_offer_hello_cancel (struct GNUNET_TRANSPORT_OfferHelloHandle *ohh)
1426 struct GNUNET_TRANSPORT_Handle *th = ohh->th;
1428 cancel_control_transmit (ohh->th, ohh->tth);
1429 GNUNET_CONTAINER_DLL_remove (th->oh_head, th->oh_tail, ohh);
1430 GNUNET_free (ohh->msg);
1436 * Checks if a given peer is connected to us
1438 * @param handle connection to transport service
1439 * @param peer the peer to check
1440 * @return #GNUNET_YES (connected) or #GNUNET_NO (disconnected)
1443 GNUNET_TRANSPORT_check_peer_connected (struct GNUNET_TRANSPORT_Handle *handle,
1444 const struct GNUNET_PeerIdentity *peer)
1447 GNUNET_CONTAINER_multipeermap_contains (handle->neighbours,
1455 * Task to call the HelloUpdateCallback of the GetHelloHandle
1457 * @param cls the `struct GNUNET_TRANSPORT_GetHelloHandle`
1458 * @param tc the scheduler task context
1461 call_hello_update_cb_async (void *cls,
1462 const struct GNUNET_SCHEDULER_TaskContext *tc)
1464 struct GNUNET_TRANSPORT_GetHelloHandle *ghh = cls;
1466 GNUNET_assert (NULL != ghh->handle->my_hello);
1467 GNUNET_assert (GNUNET_SCHEDULER_NO_TASK != ghh->notify_task);
1468 ghh->notify_task = GNUNET_SCHEDULER_NO_TASK;
1469 ghh->rec (ghh->rec_cls,
1470 (const struct GNUNET_MessageHeader *) ghh->handle->my_hello);
1475 * Obtain the HELLO message for this peer. The callback given in this function
1476 * is never called synchronously.
1478 * @param handle connection to transport service
1479 * @param rec function to call with the HELLO, sender will be our peer
1480 * identity; message and sender will be NULL on timeout
1481 * (handshake with transport service pending/failed).
1482 * cost estimate will be 0.
1483 * @param rec_cls closure for @a rec
1484 * @return handle to cancel the operation
1486 struct GNUNET_TRANSPORT_GetHelloHandle *
1487 GNUNET_TRANSPORT_get_hello (struct GNUNET_TRANSPORT_Handle *handle,
1488 GNUNET_TRANSPORT_HelloUpdateCallback rec,
1491 struct GNUNET_TRANSPORT_GetHelloHandle *hwl;
1493 hwl = GNUNET_new (struct GNUNET_TRANSPORT_GetHelloHandle);
1495 hwl->rec_cls = rec_cls;
1496 hwl->handle = handle;
1497 GNUNET_CONTAINER_DLL_insert (handle->hwl_head, handle->hwl_tail, hwl);
1498 if (handle->my_hello != NULL)
1499 hwl->notify_task = GNUNET_SCHEDULER_add_now (&call_hello_update_cb_async,
1506 * Stop receiving updates about changes to our HELLO message.
1508 * @param ghh handle to cancel
1511 GNUNET_TRANSPORT_get_hello_cancel (struct GNUNET_TRANSPORT_GetHelloHandle *ghh)
1513 struct GNUNET_TRANSPORT_Handle *handle = ghh->handle;
1515 if (GNUNET_SCHEDULER_NO_TASK != ghh->notify_task)
1516 GNUNET_SCHEDULER_cancel (ghh->notify_task);
1517 GNUNET_CONTAINER_DLL_remove (handle->hwl_head, handle->hwl_tail, ghh);
1523 * Connect to the transport service. Note that the connection may
1524 * complete (or fail) asynchronously.
1526 * @param cfg configuration to use
1527 * @param self our own identity (API should check that it matches
1528 * the identity found by transport), or NULL (no check)
1529 * @param cls closure for the callbacks
1530 * @param rec receive function to call
1531 * @param nc function to call on connect events
1532 * @param nd function to call on disconnect events
1533 * @return NULL on error
1535 struct GNUNET_TRANSPORT_Handle *
1536 GNUNET_TRANSPORT_connect (const struct GNUNET_CONFIGURATION_Handle *cfg,
1537 const struct GNUNET_PeerIdentity *self, void *cls,
1538 GNUNET_TRANSPORT_ReceiveCallback rec,
1539 GNUNET_TRANSPORT_NotifyConnect nc,
1540 GNUNET_TRANSPORT_NotifyDisconnect nd)
1542 return GNUNET_TRANSPORT_connect2 (cfg, self, cls,
1548 * Connect to the transport service. Note that the connection may
1549 * complete (or fail) asynchronously.
1551 * @param cfg configuration to use
1552 * @param self our own identity (API should check that it matches
1553 * the identity found by transport), or NULL (no check)
1554 * @param cls closure for the callbacks
1555 * @param rec receive function to call
1556 * @param nc function to call on connect events
1557 * @param nd function to call on disconnect events
1558 * @param neb function to call if we have excess bandwidth to a peer
1559 * @return NULL on error
1561 struct GNUNET_TRANSPORT_Handle *
1562 GNUNET_TRANSPORT_connect2 (const struct GNUNET_CONFIGURATION_Handle *cfg,
1563 const struct GNUNET_PeerIdentity *self, void *cls,
1564 GNUNET_TRANSPORT_ReceiveCallback rec,
1565 GNUNET_TRANSPORT_NotifyConnect nc,
1566 GNUNET_TRANSPORT_NotifyDisconnect nd,
1567 GNUNET_TRANSPORT_NotifyExcessBandwidth neb)
1569 struct GNUNET_TRANSPORT_Handle *ret;
1571 ret = GNUNET_new (struct GNUNET_TRANSPORT_Handle);
1575 ret->check_self = GNUNET_YES;
1583 ret->reconnect_delay = GNUNET_TIME_UNIT_ZERO;
1584 LOG (GNUNET_ERROR_TYPE_DEBUG,
1585 "Connecting to transport service.\n");
1586 ret->client = GNUNET_CLIENT_connect ("transport", cfg);
1587 if (NULL == ret->client)
1593 GNUNET_CONTAINER_multipeermap_create (STARTING_NEIGHBOURS_SIZE,
1596 GNUNET_CONTAINER_heap_create (GNUNET_CONTAINER_HEAP_ORDER_MIN);
1597 schedule_control_transmit (ret, sizeof (struct StartMessage),
1604 * Disconnect from the transport service.
1606 * @param handle handle to the service as returned from #GNUNET_TRANSPORT_connect()
1609 GNUNET_TRANSPORT_disconnect (struct GNUNET_TRANSPORT_Handle *handle)
1611 LOG (GNUNET_ERROR_TYPE_DEBUG,
1612 "Transport disconnect called!\n");
1613 /* this disconnects all neighbours... */
1614 if (handle->reconnect_task == GNUNET_SCHEDULER_NO_TASK)
1615 disconnect_and_schedule_reconnect (handle);
1616 /* and now we stop trying to connect again... */
1617 if (handle->reconnect_task != GNUNET_SCHEDULER_NO_TASK)
1619 GNUNET_SCHEDULER_cancel (handle->reconnect_task);
1620 handle->reconnect_task = GNUNET_SCHEDULER_NO_TASK;
1622 GNUNET_CONTAINER_multipeermap_destroy (handle->neighbours);
1623 handle->neighbours = NULL;
1624 if (handle->quota_task != GNUNET_SCHEDULER_NO_TASK)
1626 GNUNET_SCHEDULER_cancel (handle->quota_task);
1627 handle->quota_task = GNUNET_SCHEDULER_NO_TASK;
1629 GNUNET_free_non_null (handle->my_hello);
1630 handle->my_hello = NULL;
1631 GNUNET_assert (handle->tc_head == NULL);
1632 GNUNET_assert (handle->tc_tail == NULL);
1633 GNUNET_assert (handle->hwl_head == NULL);
1634 GNUNET_assert (handle->hwl_tail == NULL);
1635 GNUNET_CONTAINER_heap_destroy (handle->ready_heap);
1636 handle->ready_heap = NULL;
1637 GNUNET_free (handle);
1642 * Check if we could queue a message of the given size for
1643 * transmission. The transport service will take both its
1644 * internal buffers and bandwidth limits imposed by the
1645 * other peer into consideration when answering this query.
1647 * @param handle connection to transport service
1648 * @param target who should receive the message
1649 * @param size how big is the message we want to transmit?
1650 * @param timeout after how long should we give up (and call
1651 * notify with buf NULL and size 0)?
1652 * @param notify function to call when we are ready to
1653 * send such a message
1654 * @param notify_cls closure for @a notify
1655 * @return NULL if someone else is already waiting to be notified
1656 * non-NULL if the notify callback was queued (can be used to cancel
1657 * using #GNUNET_TRANSPORT_notify_transmit_ready_cancel)
1659 struct GNUNET_TRANSPORT_TransmitHandle *
1660 GNUNET_TRANSPORT_notify_transmit_ready (struct GNUNET_TRANSPORT_Handle *handle,
1661 const struct GNUNET_PeerIdentity *target,
1663 struct GNUNET_TIME_Relative timeout,
1664 GNUNET_TRANSPORT_TransmitReadyNotify notify,
1667 struct Neighbour *n;
1668 struct GNUNET_TRANSPORT_TransmitHandle *th;
1669 struct GNUNET_TIME_Relative delay;
1671 n = neighbour_find (handle, target);
1674 /* use GNUNET_TRANSPORT_try_connect first, only use this function
1675 * once a connection has been established */
1681 /* attempt to send two messages at the same time to the same peer */
1685 GNUNET_assert (NULL == n->hn);
1686 th = GNUNET_new (struct GNUNET_TRANSPORT_TransmitHandle);
1688 th->notify = notify;
1689 th->notify_cls = notify_cls;
1690 th->timeout = GNUNET_TIME_relative_to_absolute (timeout);
1691 th->notify_size = size;
1693 /* calculate when our transmission should be ready */
1694 delay = GNUNET_BANDWIDTH_tracker_get_delay (&n->out_tracker, size + n->traffic_overhead);
1695 n->traffic_overhead = 0;
1696 if (delay.rel_value_us > timeout.rel_value_us)
1697 delay.rel_value_us = 0; /* notify immediately (with failure) */
1698 LOG (GNUNET_ERROR_TYPE_DEBUG,
1699 "Bandwidth tracker allows next transmission to peer %s in %s\n",
1700 GNUNET_i2s (target),
1701 GNUNET_STRINGS_relative_time_to_string (delay, GNUNET_YES));
1702 n->hn = GNUNET_CONTAINER_heap_insert (handle->ready_heap, n, delay.rel_value_us);
1703 schedule_transmission (handle);
1709 * Cancel the specified transmission-ready notification.
1711 * @param th handle returned from #GNUNET_TRANSPORT_notify_transmit_ready()
1714 GNUNET_TRANSPORT_notify_transmit_ready_cancel (struct GNUNET_TRANSPORT_TransmitHandle *th)
1716 struct Neighbour *n;
1718 GNUNET_assert (NULL == th->next);
1719 GNUNET_assert (NULL == th->prev);
1721 GNUNET_assert (th == n->th);
1725 GNUNET_CONTAINER_heap_remove_node (n->hn);
1730 GNUNET_assert (GNUNET_SCHEDULER_NO_TASK != th->timeout_task);
1731 GNUNET_SCHEDULER_cancel (th->timeout_task);
1732 th->timeout_task = GNUNET_SCHEDULER_NO_TASK;
1738 /* end of transport_api.c */