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_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);
423 * The outbound quota has changed in a way that may require
424 * us to reset the timeout. Update the timeout.
426 * @param cls the `struct Neighbour` for which the timeout changed
429 outbound_bw_tracker_update (void *cls)
431 struct Neighbour *n = cls;
432 struct GNUNET_TIME_Relative delay;
436 delay = GNUNET_BANDWIDTH_tracker_get_delay (&n->out_tracker,
437 n->th->notify_size + n->traffic_overhead);
438 LOG (GNUNET_ERROR_TYPE_DEBUG,
439 "New outbound delay %llu us\n",
440 GNUNET_STRINGS_relative_time_to_string (delay,
442 GNUNET_CONTAINER_heap_update_cost (n->h->ready_heap,
443 n->hn, delay.rel_value_us);
444 schedule_transmission (n->h);
449 * Function called by the bandwidth tracker if we have excess
452 * @param cls the `struct Neighbour` that has excess bandwidth
455 notify_excess_cb (void *cls)
457 struct Neighbour *n = cls;
458 struct GNUNET_TRANSPORT_Handle *h = n->h;
460 if (NULL != h->neb_cb)
467 * Add neighbour to our list
469 * @return NULL if this API is currently disconnecting from the service
471 static struct Neighbour *
472 neighbour_add (struct GNUNET_TRANSPORT_Handle *h,
473 const struct GNUNET_PeerIdentity *pid)
477 LOG (GNUNET_ERROR_TYPE_DEBUG,
478 "Creating entry for neighbour `%4s'.\n",
480 n = GNUNET_new (struct Neighbour);
483 n->is_ready = GNUNET_YES;
484 n->traffic_overhead = 0;
485 GNUNET_BANDWIDTH_tracker_init2 (&n->out_tracker,
486 &outbound_bw_tracker_update, n,
487 GNUNET_CONSTANTS_DEFAULT_BW_IN_OUT,
488 MAX_BANDWIDTH_CARRY_S,
491 GNUNET_assert (GNUNET_OK ==
492 GNUNET_CONTAINER_multipeermap_put (h->neighbours,
494 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
500 * Iterator over hash map entries, for deleting state of a neighbour.
502 * @param cls the `struct GNUNET_TRANSPORT_Handle *`
503 * @param key peer identity
504 * @param value value in the hash map, the neighbour entry to delete
505 * @return #GNUNET_YES if we should continue to
510 neighbour_delete (void *cls,
511 const struct GNUNET_PeerIdentity *key, void *value)
513 struct GNUNET_TRANSPORT_Handle *handle = cls;
514 struct Neighbour *n = value;
516 if (NULL != handle->nd_cb)
517 handle->nd_cb (handle->cls, &n->id);
518 GNUNET_assert (NULL == n->th);
519 GNUNET_assert (NULL == n->hn);
520 GNUNET_assert (GNUNET_YES ==
521 GNUNET_CONTAINER_multipeermap_remove (handle->neighbours, key,
523 GNUNET_BANDWIDTH_tracker_notification_stop (&n->out_tracker);
530 * Function we use for handling incoming messages.
532 * @param cls closure, a `struct GNUNET_TRANSPORT_Handle *`
533 * @param msg message received, NULL on timeout or fatal error
536 demultiplexer (void *cls, const struct GNUNET_MessageHeader *msg)
538 struct GNUNET_TRANSPORT_Handle *h = cls;
539 const struct DisconnectInfoMessage *dim;
540 const struct ConnectInfoMessage *cim;
541 const struct InboundMessage *im;
542 const struct GNUNET_MessageHeader *imm;
543 const struct SendOkMessage *okm;
544 const struct QuotaSetMessage *qm;
545 struct GNUNET_TRANSPORT_GetHelloHandle *hwl;
546 struct GNUNET_TRANSPORT_GetHelloHandle *next_hwl;
548 struct GNUNET_PeerIdentity me;
551 uint32_t bytes_physical;
553 GNUNET_assert (NULL != h->client);
554 if (GNUNET_YES == h->reconnecting)
560 LOG (GNUNET_ERROR_TYPE_DEBUG,
561 "Error receiving from transport service, disconnecting temporarily.\n");
562 h->reconnecting = GNUNET_YES;
563 disconnect_and_schedule_reconnect (h);
566 GNUNET_CLIENT_receive (h->client, &demultiplexer, h,
567 GNUNET_TIME_UNIT_FOREVER_REL);
568 size = ntohs (msg->size);
569 switch (ntohs (msg->type))
571 case GNUNET_MESSAGE_TYPE_HELLO:
573 GNUNET_HELLO_get_id ((const struct GNUNET_HELLO_Message *) msg, &me))
578 LOG (GNUNET_ERROR_TYPE_DEBUG,
579 "Receiving (my own) `%s' message, I am `%4s'.\n", "HELLO",
581 GNUNET_free_non_null (h->my_hello);
583 if (size < sizeof (struct GNUNET_MessageHeader))
588 h->my_hello = GNUNET_malloc (size);
589 memcpy (h->my_hello, msg, size);
593 next_hwl = hwl->next;
594 hwl->rec (hwl->rec_cls,
595 (const struct GNUNET_MessageHeader *) h->my_hello);
599 case GNUNET_MESSAGE_TYPE_TRANSPORT_CONNECT:
600 if (size < sizeof (struct ConnectInfoMessage))
605 cim = (const struct ConnectInfoMessage *) msg;
607 sizeof (struct ConnectInfoMessage))
612 LOG (GNUNET_ERROR_TYPE_DEBUG,
613 "Receiving `%s' message for `%4s'.\n",
614 "CONNECT", GNUNET_i2s (&cim->id));
615 n = neighbour_find (h, &cim->id);
621 n = neighbour_add (h, &cim->id);
622 LOG (GNUNET_ERROR_TYPE_DEBUG,
623 "Receiving `%s' message for `%4s' with quota %u\n",
625 GNUNET_i2s (&cim->id),
626 ntohl (cim->quota_out.value__));
627 GNUNET_BANDWIDTH_tracker_update_quota (&n->out_tracker, cim->quota_out);
628 if (h->nc_cb != NULL)
629 h->nc_cb (h->cls, &n->id);
631 case GNUNET_MESSAGE_TYPE_TRANSPORT_DISCONNECT:
632 if (size != sizeof (struct DisconnectInfoMessage))
637 dim = (const struct DisconnectInfoMessage *) msg;
638 GNUNET_break (ntohl (dim->reserved) == 0);
639 LOG (GNUNET_ERROR_TYPE_DEBUG,
640 "Receiving `%s' message for `%4s'.\n",
641 "DISCONNECT", GNUNET_i2s (&dim->peer));
642 n = neighbour_find (h, &dim->peer);
648 neighbour_delete (h, &dim->peer, n);
650 case GNUNET_MESSAGE_TYPE_TRANSPORT_SEND_OK:
651 if (size != sizeof (struct SendOkMessage))
656 okm = (const struct SendOkMessage *) msg;
657 bytes_msg = ntohl (okm->bytes_msg);
658 bytes_physical = ntohl (okm->bytes_physical);
659 LOG (GNUNET_ERROR_TYPE_DEBUG,
660 "Receiving SEND_OK message, transmission %s.\n",
661 ntohl (okm->success) == GNUNET_OK ? "succeeded" : "failed");
663 n = neighbour_find (h, &okm->peer);
667 if (bytes_physical >= bytes_msg)
669 LOG (GNUNET_ERROR_TYPE_DEBUG,
670 "Overhead for %u byte message: %u\n",
671 bytes_msg, bytes_physical - bytes_msg);
672 n->traffic_overhead += bytes_physical - bytes_msg;
674 GNUNET_break (GNUNET_NO == n->is_ready);
675 n->is_ready = GNUNET_YES;
676 if ((NULL != n->th) && (NULL == n->hn))
678 GNUNET_assert (GNUNET_SCHEDULER_NO_TASK != n->th->timeout_task);
679 GNUNET_SCHEDULER_cancel (n->th->timeout_task);
680 n->th->timeout_task = GNUNET_SCHEDULER_NO_TASK;
681 /* we've been waiting for this (congestion, not quota,
682 * caused delayed transmission) */
683 n->hn = GNUNET_CONTAINER_heap_insert (h->ready_heap, n, 0);
684 schedule_transmission (h);
687 case GNUNET_MESSAGE_TYPE_TRANSPORT_RECV:
688 LOG (GNUNET_ERROR_TYPE_DEBUG,
689 "Receiving `%s' message.\n",
692 sizeof (struct InboundMessage) + sizeof (struct GNUNET_MessageHeader))
697 im = (const struct InboundMessage *) msg;
698 imm = (const struct GNUNET_MessageHeader *) &im[1];
699 if (ntohs (imm->size) + sizeof (struct InboundMessage) != size)
704 LOG (GNUNET_ERROR_TYPE_DEBUG,
705 "Received message of type %u from `%4s'.\n",
706 ntohs (imm->type), GNUNET_i2s (&im->peer));
707 n = neighbour_find (h, &im->peer);
714 h->rec (h->cls, &im->peer, imm);
716 case GNUNET_MESSAGE_TYPE_TRANSPORT_SET_QUOTA:
717 LOG (GNUNET_ERROR_TYPE_DEBUG,
718 "Receiving `%s' message.\n", "SET_QUOTA");
719 if (size != sizeof (struct QuotaSetMessage))
724 qm = (const struct QuotaSetMessage *) msg;
725 n = neighbour_find (h, &qm->peer);
728 LOG (GNUNET_ERROR_TYPE_DEBUG,
729 "Receiving `%s' message for `%4s' with quota %u\n",
731 GNUNET_i2s (&qm->peer),
732 ntohl (qm->quota.value__));
733 GNUNET_BANDWIDTH_tracker_update_quota (&n->out_tracker, qm->quota);
736 LOG (GNUNET_ERROR_TYPE_ERROR,
737 _("Received unexpected message of type %u in %s:%u\n"),
738 ntohs (msg->type), __FILE__, __LINE__);
746 * A transmission request could not be satisfied because of
747 * network congestion. Notify the initiator and clean up.
749 * @param cls the `struct GNUNET_TRANSPORT_TransmitHandle`
750 * @param tc scheduler context
753 timeout_request_due_to_congestion (void *cls,
754 const struct GNUNET_SCHEDULER_TaskContext *tc)
756 struct GNUNET_TRANSPORT_TransmitHandle *th = cls;
757 struct Neighbour *n = th->neighbour;
759 n->th->timeout_task = GNUNET_SCHEDULER_NO_TASK;
760 GNUNET_assert (th == n->th);
761 GNUNET_assert (NULL == n->hn);
763 th->notify (th->notify_cls, 0, NULL);
769 * Transmit message(s) to service.
771 * @param cls handle to transport
772 * @param size number of bytes available in @a buf
773 * @param buf where to copy the message
774 * @return number of bytes copied to @a buf
777 transport_notify_ready (void *cls, size_t size, void *buf)
779 struct GNUNET_TRANSPORT_Handle *h = cls;
780 struct GNUNET_TRANSPORT_TransmitHandle *th;
783 struct OutboundMessage obm;
788 GNUNET_assert (NULL != h->client);
792 /* transmission failed */
793 disconnect_and_schedule_reconnect (h);
799 /* first send control messages */
800 while ((NULL != (th = h->control_head)) && (th->notify_size <= size))
802 GNUNET_CONTAINER_DLL_remove (h->control_head, h->control_tail, th);
803 nret = th->notify (th->notify_cls, size, &cbuf[ret]);
804 LOG (GNUNET_ERROR_TYPE_DEBUG,
805 "Added %u bytes of control message at %u\n",
812 /* then, if possible and no control messages pending, send data messages */
813 while ((NULL == h->control_head) &&
814 (NULL != (n = GNUNET_CONTAINER_heap_peek (h->ready_heap))))
816 if (GNUNET_YES != n->is_ready)
818 /* peer not ready, wait for notification! */
819 GNUNET_assert (n == GNUNET_CONTAINER_heap_remove_root (h->ready_heap));
821 GNUNET_assert (GNUNET_SCHEDULER_NO_TASK == n->th->timeout_task);
822 n->th->timeout_task =
823 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_absolute_get_remaining
825 &timeout_request_due_to_congestion,
830 if (th->notify_size + sizeof (struct OutboundMessage) > size)
831 break; /* does not fit */
832 if (GNUNET_BANDWIDTH_tracker_get_delay
833 (&n->out_tracker, th->notify_size).rel_value_us > 0)
834 break; /* too early */
835 GNUNET_assert (n == GNUNET_CONTAINER_heap_remove_root (h->ready_heap));
838 n->is_ready = GNUNET_NO;
839 GNUNET_assert (size >= sizeof (struct OutboundMessage));
841 th->notify (th->notify_cls, size - sizeof (struct OutboundMessage),
842 &cbuf[ret + sizeof (struct OutboundMessage)]);
843 GNUNET_assert (mret <= size - sizeof (struct OutboundMessage));
846 GNUNET_assert (mret + sizeof (struct OutboundMessage) <
847 GNUNET_SERVER_MAX_MESSAGE_SIZE);
848 obm.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SEND);
849 obm.header.size = htons (mret + sizeof (struct OutboundMessage));
850 obm.reserved = htonl (0);
852 GNUNET_TIME_relative_hton (GNUNET_TIME_absolute_get_remaining
855 memcpy (&cbuf[ret], &obm, sizeof (struct OutboundMessage));
856 ret += (mret + sizeof (struct OutboundMessage));
857 size -= (mret + sizeof (struct OutboundMessage));
858 GNUNET_BANDWIDTH_tracker_consume (&n->out_tracker, mret);
862 /* if there are more pending messages, try to schedule those */
863 schedule_transmission (h);
864 LOG (GNUNET_ERROR_TYPE_DEBUG,
865 "Transmitting %u bytes to transport service\n",
872 * Schedule the task to send one message, either from the control
873 * list or the peer message queues to the service.
875 * @param cls transport service to schedule a transmission for
876 * @param tc scheduler context
879 schedule_transmission_task (void *cls,
880 const struct GNUNET_SCHEDULER_TaskContext *tc)
882 struct GNUNET_TRANSPORT_Handle *h = cls;
884 struct GNUNET_TRANSPORT_TransmitHandle *th;
887 h->quota_task = GNUNET_SCHEDULER_NO_TASK;
888 GNUNET_assert (NULL != h->client);
889 /* destroy all requests that have timed out */
890 while ((NULL != (n = GNUNET_CONTAINER_heap_peek (h->ready_heap))) &&
891 (0 == GNUNET_TIME_absolute_get_remaining (n->th->timeout).rel_value_us))
893 /* notify client that the request could not be satisfied within
894 * the given time constraints */
897 GNUNET_assert (n == GNUNET_CONTAINER_heap_remove_root (h->ready_heap));
899 LOG (GNUNET_ERROR_TYPE_DEBUG,
900 "Signalling timeout for transmission to peer %s due to congestion\n",
901 GNUNET_i2s (&n->id));
902 GNUNET_assert (0 == th->notify (th->notify_cls, 0, NULL));
907 if (NULL != h->control_head)
909 size = h->control_head->notify_size;
913 n = GNUNET_CONTAINER_heap_peek (h->ready_heap);
915 return; /* no pending messages */
916 size = n->th->notify_size + sizeof (struct OutboundMessage);
918 LOG (GNUNET_ERROR_TYPE_DEBUG,
919 "Calling notify_transmit_ready\n");
921 GNUNET_CLIENT_notify_transmit_ready (h->client, size,
922 GNUNET_TIME_UNIT_FOREVER_REL,
923 GNUNET_NO, &transport_notify_ready,
925 GNUNET_assert (NULL != h->cth);
930 * Schedule the task to send one message, either from the control
931 * list or the peer message queues to the service.
933 * @param h transport service to schedule a transmission for
936 schedule_transmission (struct GNUNET_TRANSPORT_Handle *h)
938 struct GNUNET_TIME_Relative delay;
941 GNUNET_assert (NULL != h->client);
942 if (h->quota_task != GNUNET_SCHEDULER_NO_TASK)
944 GNUNET_SCHEDULER_cancel (h->quota_task);
945 h->quota_task = GNUNET_SCHEDULER_NO_TASK;
947 if (NULL != h->control_head)
948 delay = GNUNET_TIME_UNIT_ZERO;
949 else if (NULL != (n = GNUNET_CONTAINER_heap_peek (h->ready_heap)))
952 GNUNET_BANDWIDTH_tracker_get_delay (&n->out_tracker,
953 n->th->notify_size + n->traffic_overhead);
954 n->traffic_overhead = 0;
957 return; /* no work to be done */
958 LOG (GNUNET_ERROR_TYPE_DEBUG,
959 "Scheduling next transmission to service in %s\n",
960 GNUNET_STRINGS_relative_time_to_string (delay, GNUNET_YES));
962 GNUNET_SCHEDULER_add_delayed (delay, &schedule_transmission_task, h);
967 * Queue control request for transmission to the transport
970 * @param h handle to the transport service
971 * @param size number of bytes to be transmitted
972 * @param notify function to call to get the content
973 * @param notify_cls closure for @a notify
974 * @return a `struct GNUNET_TRANSPORT_TransmitHandle`
976 static struct GNUNET_TRANSPORT_TransmitHandle *
977 schedule_control_transmit (struct GNUNET_TRANSPORT_Handle *h, size_t size,
978 GNUNET_TRANSPORT_TransmitReadyNotify notify,
981 struct GNUNET_TRANSPORT_TransmitHandle *th;
983 LOG (GNUNET_ERROR_TYPE_DEBUG,
984 "Control transmit of %u bytes requested\n",
986 th = GNUNET_new (struct GNUNET_TRANSPORT_TransmitHandle);
988 th->notify_cls = notify_cls;
989 th->notify_size = size;
990 GNUNET_CONTAINER_DLL_insert_tail (h->control_head, h->control_tail, th);
991 schedule_transmission (h);
997 * Transmit START message to service.
1000 * @param size number of bytes available in @a buf
1001 * @param buf where to copy the message
1002 * @return number of bytes copied to @a buf
1005 send_start (void *cls, size_t size, void *buf)
1007 struct GNUNET_TRANSPORT_Handle *h = cls;
1008 struct StartMessage s;
1013 /* Can only be shutdown, just give up */
1014 LOG (GNUNET_ERROR_TYPE_DEBUG,
1015 "Shutdown while trying to transmit `%s' request.\n",
1019 LOG (GNUNET_ERROR_TYPE_DEBUG,
1020 "Transmitting `%s' request.\n",
1022 GNUNET_assert (size >= sizeof (struct StartMessage));
1023 s.header.size = htons (sizeof (struct StartMessage));
1024 s.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_START);
1030 s.options = htonl (options);
1032 memcpy (buf, &s, sizeof (struct StartMessage));
1033 GNUNET_CLIENT_receive (h->client, &demultiplexer, h,
1034 GNUNET_TIME_UNIT_FOREVER_REL);
1035 return sizeof (struct StartMessage);
1040 * Try again to connect to transport service.
1042 * @param cls the handle to the transport service
1043 * @param tc scheduler context
1046 reconnect (void *cls,
1047 const struct GNUNET_SCHEDULER_TaskContext *tc)
1049 struct GNUNET_TRANSPORT_Handle *h = cls;
1051 h->reconnect_task = GNUNET_SCHEDULER_NO_TASK;
1052 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1054 /* shutdown, just give up */
1057 LOG (GNUNET_ERROR_TYPE_DEBUG,
1058 "Connecting to transport service.\n");
1059 GNUNET_assert (NULL == h->client);
1060 GNUNET_assert (NULL == h->control_head);
1061 GNUNET_assert (NULL == h->control_tail);
1062 h->reconnecting = GNUNET_NO;
1063 h->client = GNUNET_CLIENT_connect ("transport", h->cfg);
1065 GNUNET_assert (NULL != h->client);
1066 schedule_control_transmit (h, sizeof (struct StartMessage),
1072 * Function that will schedule the job that will try
1073 * to connect us again to the client.
1075 * @param h transport service to reconnect
1078 disconnect_and_schedule_reconnect (struct GNUNET_TRANSPORT_Handle *h)
1080 struct GNUNET_TRANSPORT_TransmitHandle *th;
1082 GNUNET_assert (h->reconnect_task == GNUNET_SCHEDULER_NO_TASK);
1085 GNUNET_CLIENT_notify_transmit_ready_cancel (h->cth);
1088 if (NULL != h->client)
1090 GNUNET_CLIENT_disconnect (h->client);
1092 /* LOG (GNUNET_ERROR_TYPE_ERROR,
1093 "Client disconnect done \n");*/
1095 /* Forget about all neighbours that we used to be connected to */
1096 GNUNET_CONTAINER_multipeermap_iterate (h->neighbours,
1097 &neighbour_delete, h);
1098 if (h->quota_task != GNUNET_SCHEDULER_NO_TASK)
1100 GNUNET_SCHEDULER_cancel (h->quota_task);
1101 h->quota_task = GNUNET_SCHEDULER_NO_TASK;
1103 while ((NULL != (th = h->control_head)))
1105 GNUNET_CONTAINER_DLL_remove (h->control_head, h->control_tail, th);
1106 th->notify (th->notify_cls, 0, NULL);
1109 LOG (GNUNET_ERROR_TYPE_DEBUG,
1110 "Scheduling task to reconnect to transport service in %s.\n",
1111 GNUNET_STRINGS_relative_time_to_string(h->reconnect_delay, GNUNET_YES));
1113 GNUNET_SCHEDULER_add_delayed (h->reconnect_delay, &reconnect, h);
1114 h->reconnect_delay = GNUNET_TIME_STD_BACKOFF (h->reconnect_delay);
1119 * Cancel control request for transmission to the transport service.
1121 * @param th handle to the transport service
1122 * @param tth transmit handle to cancel
1125 cancel_control_transmit (struct GNUNET_TRANSPORT_Handle *th,
1126 struct GNUNET_TRANSPORT_TransmitHandle *tth)
1128 LOG (GNUNET_ERROR_TYPE_DEBUG,
1129 "Canceling transmit of contral transmission requested\n");
1130 GNUNET_CONTAINER_DLL_remove (th->control_head, th->control_tail, tth);
1137 * Send REQUEST_CONNECT message to the service.
1139 * @param cls the `struct GNUNET_PeerIdentity`
1140 * @param size number of bytes available in @a buf
1141 * @param buf where to copy the message
1142 * @return number of bytes copied to @a buf
1145 send_try_connect (void *cls, size_t size, void *buf)
1147 struct GNUNET_TRANSPORT_TryConnectHandle *tch = cls;
1148 struct TransportRequestConnectMessage msg;
1152 if (NULL != tch->cb)
1153 tch->cb (tch->cb_cls, GNUNET_SYSERR);
1154 GNUNET_CONTAINER_DLL_remove (tch->th->tc_head, tch->th->tc_tail, tch);
1155 LOG (GNUNET_ERROR_TYPE_DEBUG,
1156 "Discarding `%s' request to `%4s' due to error in transport service connection.\n",
1158 GNUNET_i2s (&tch->pid));
1162 LOG (GNUNET_ERROR_TYPE_DEBUG,
1163 "Transmitting `%s' request with respect to `%4s'.\n",
1165 GNUNET_i2s (&tch->pid));
1166 GNUNET_assert (size >= sizeof (struct TransportRequestConnectMessage));
1167 msg.header.size = htons (sizeof (struct TransportRequestConnectMessage));
1168 msg.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_REQUEST_CONNECT);
1169 msg.reserved = htonl (0);
1170 msg.peer = tch->pid;
1171 memcpy (buf, &msg, sizeof (msg));
1172 if (NULL != tch->cb)
1173 tch->cb (tch->cb_cls, GNUNET_OK);
1174 GNUNET_CONTAINER_DLL_remove (tch->th->tc_head, tch->th->tc_tail, tch);
1176 return sizeof (struct TransportRequestConnectMessage);
1180 * Ask the transport service to establish a connection to
1183 * @param handle connection to transport service
1184 * @param target who we should try to connect to
1185 * @param cb callback to be called when request was transmitted to transport
1187 * @param cb_cls closure for the callback
1188 * @return a `struct GNUNET_TRANSPORT_TryConnectHandle` handle or
1189 * NULL on failure (cb will not be called)
1191 struct GNUNET_TRANSPORT_TryConnectHandle *
1192 GNUNET_TRANSPORT_try_connect (struct GNUNET_TRANSPORT_Handle *handle,
1193 const struct GNUNET_PeerIdentity *target,
1194 GNUNET_TRANSPORT_TryConnectCallback cb,
1197 struct GNUNET_TRANSPORT_TryConnectHandle *tch = NULL;
1199 if (NULL == handle->client)
1201 tch = GNUNET_new (struct GNUNET_TRANSPORT_TryConnectHandle);
1203 tch->pid = *(target);
1205 tch->cb_cls = cb_cls;
1206 tch->tth = schedule_control_transmit (handle,
1207 sizeof (struct TransportRequestConnectMessage),
1208 &send_try_connect, tch);
1209 GNUNET_CONTAINER_DLL_insert(handle->tc_head, handle->tc_tail, tch);
1215 * Cancel the request to transport to try a connect
1216 * Callback will not be called
1218 * @param tch the handle to cancel
1221 GNUNET_TRANSPORT_try_connect_cancel (struct GNUNET_TRANSPORT_TryConnectHandle *tch)
1223 struct GNUNET_TRANSPORT_Handle *th;
1226 cancel_control_transmit (th, tch->tth);
1227 GNUNET_CONTAINER_DLL_remove (th->tc_head, th->tc_tail, tch);
1233 * Send HELLO message to the service.
1235 * @param cls the HELLO message to send
1236 * @param size number of bytes available in @a buf
1237 * @param buf where to copy the message
1238 * @return number of bytes copied to @a buf
1241 send_hello (void *cls, size_t size, void *buf)
1243 struct GNUNET_TRANSPORT_OfferHelloHandle *ohh = cls;
1244 struct GNUNET_MessageHeader *msg = ohh->msg;
1246 struct GNUNET_SCHEDULER_TaskContext tc;
1248 tc.read_ready = NULL;
1249 tc.write_ready = NULL;
1250 tc.reason = GNUNET_SCHEDULER_REASON_TIMEOUT;
1253 LOG (GNUNET_ERROR_TYPE_DEBUG,
1254 "Timeout while trying to transmit `%s' request.\n",
1256 if (NULL != ohh->cont)
1257 ohh->cont (ohh->cls, &tc);
1259 GNUNET_CONTAINER_DLL_remove (ohh->th->oh_head, ohh->th->oh_tail, ohh);
1263 LOG (GNUNET_ERROR_TYPE_DEBUG,
1264 "Transmitting `%s' request.\n",
1266 ssize = ntohs (msg->size);
1267 GNUNET_assert (size >= ssize);
1268 memcpy (buf, msg, ssize);
1270 tc.reason = GNUNET_SCHEDULER_REASON_READ_READY;
1271 if (NULL != ohh->cont)
1272 ohh->cont (ohh->cls, &tc);
1273 GNUNET_CONTAINER_DLL_remove (ohh->th->oh_head, ohh->th->oh_tail, ohh);
1280 * Send traffic metric message to the service.
1282 * @param cls the message to send
1283 * @param size number of bytes available in @a buf
1284 * @param buf where to copy the message
1285 * @return number of bytes copied to @a buf
1288 send_metric (void *cls, size_t size, void *buf)
1290 struct TrafficMetricMessage *msg = cls;
1295 LOG (GNUNET_ERROR_TYPE_DEBUG,
1296 "Timeout while trying to transmit `%s' request.\n",
1301 LOG (GNUNET_ERROR_TYPE_DEBUG,
1302 "Transmitting `%s' request.\n",
1304 ssize = ntohs (msg->header.size);
1305 GNUNET_assert (size >= ssize);
1306 memcpy (buf, msg, ssize);
1313 * Set transport metrics for a peer and a direction
1315 * @param handle transport handle
1316 * @param peer the peer to set the metric for
1317 * @param inbound set inbound direction (#GNUNET_YES or #GNUNET_NO)
1318 * @param outbound set outbound direction (#GNUNET_YES or #GNUNET_NO)
1319 * @param ats the metric as ATS information
1320 * @param ats_count the number of metrics
1322 * Supported ATS values:
1323 * #GNUNET_ATS_QUALITY_NET_DELAY (value in ms)
1324 * #GNUNET_ATS_QUALITY_NET_DISTANCE (value in count(hops))
1327 * To enforce a delay of 10 ms for peer p1 in sending direction use:
1329 * struct GNUNET_ATS_Information ats;
1330 * ats.type = ntohl (GNUNET_ATS_QUALITY_NET_DELAY);
1331 * ats.value = ntohl (10);
1332 * GNUNET_TRANSPORT_set_traffic_metric (th, p1, TM_SEND, &ats, 1);
1335 * Delay restrictions in receiving direction will be enforced with
1339 GNUNET_TRANSPORT_set_traffic_metric (struct GNUNET_TRANSPORT_Handle *handle,
1340 const struct GNUNET_PeerIdentity *peer,
1343 const struct GNUNET_ATS_Information *ats,
1346 struct TrafficMetricMessage *msg;
1348 GNUNET_assert ((outbound == GNUNET_YES) || (outbound == GNUNET_NO));
1349 GNUNET_assert ((inbound == GNUNET_YES) || (inbound == GNUNET_NO));
1350 if ((GNUNET_NO == inbound) && (GNUNET_NO == outbound))
1355 size_t len = sizeof (struct TrafficMetricMessage) +
1356 ats_count * sizeof (struct GNUNET_ATS_Information);
1358 msg = GNUNET_malloc (len);
1359 msg->header.size = htons (len);
1360 msg->header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_TRAFFIC_METRIC);
1361 msg->direction = htons (0 + outbound + 2 * inbound);
1362 msg->ats_count = htons (ats_count);
1363 msg->peer = (*peer);
1364 memcpy (&msg[1], ats, ats_count * sizeof (struct GNUNET_ATS_Information));
1365 schedule_control_transmit (handle, len,
1371 * Offer the transport service the HELLO of another peer. Note that
1372 * the transport service may just ignore this message if the HELLO is
1373 * malformed or useless due to our local configuration.
1375 * @param handle connection to transport service
1376 * @param hello the hello message
1377 * @param cont continuation to call when HELLO has been sent,
1378 * tc reason #GNUNET_SCHEDULER_REASON_TIMEOUT for fail
1379 * tc reasong #GNUNET_SCHEDULER_REASON_READ_READY for success
1380 * @param cls closure for continuation
1381 * @return a `struct GNUNET_TRANSPORT_OfferHelloHandle` handle or NULL on failure,
1382 * in case of failure cont will not be called
1385 struct GNUNET_TRANSPORT_OfferHelloHandle *
1386 GNUNET_TRANSPORT_offer_hello (struct GNUNET_TRANSPORT_Handle *handle,
1387 const struct GNUNET_MessageHeader *hello,
1388 GNUNET_SCHEDULER_Task cont, void *cls)
1390 struct GNUNET_TRANSPORT_OfferHelloHandle *ohh;
1391 struct GNUNET_MessageHeader *msg;
1392 struct GNUNET_PeerIdentity peer;
1395 if (NULL == handle->client)
1397 GNUNET_break (ntohs (hello->type) == GNUNET_MESSAGE_TYPE_HELLO);
1398 size = ntohs (hello->size);
1399 GNUNET_break (size >= sizeof (struct GNUNET_MessageHeader));
1401 GNUNET_HELLO_get_id ((const struct GNUNET_HELLO_Message *) hello, &peer))
1407 msg = GNUNET_malloc (size);
1408 memcpy (msg, hello, size);
1409 LOG (GNUNET_ERROR_TYPE_DEBUG,
1410 "Offering `%s' message of `%4s' to transport for validation.\n", "HELLO",
1411 GNUNET_i2s (&peer));
1413 ohh = GNUNET_new (struct GNUNET_TRANSPORT_OfferHelloHandle);
1418 ohh->tth = schedule_control_transmit (handle, size,
1420 GNUNET_CONTAINER_DLL_insert (handle->oh_head, handle->oh_tail, ohh);
1426 * Cancel the request to transport to offer the HELLO message
1428 * @param ohh the GNUNET_TRANSPORT_OfferHelloHandle to cancel
1431 GNUNET_TRANSPORT_offer_hello_cancel (struct GNUNET_TRANSPORT_OfferHelloHandle *ohh)
1433 struct GNUNET_TRANSPORT_Handle *th = ohh->th;
1435 cancel_control_transmit (ohh->th, ohh->tth);
1436 GNUNET_CONTAINER_DLL_remove (th->oh_head, th->oh_tail, ohh);
1437 GNUNET_free (ohh->msg);
1443 * Checks if a given peer is connected to us
1445 * @param handle connection to transport service
1446 * @param peer the peer to check
1447 * @return #GNUNET_YES (connected) or #GNUNET_NO (disconnected)
1450 GNUNET_TRANSPORT_check_peer_connected (struct GNUNET_TRANSPORT_Handle *handle,
1451 const struct GNUNET_PeerIdentity *peer)
1454 GNUNET_CONTAINER_multipeermap_contains (handle->neighbours,
1462 * Task to call the HelloUpdateCallback of the GetHelloHandle
1464 * @param cls the `struct GNUNET_TRANSPORT_GetHelloHandle`
1465 * @param tc the scheduler task context
1468 call_hello_update_cb_async (void *cls,
1469 const struct GNUNET_SCHEDULER_TaskContext *tc)
1471 struct GNUNET_TRANSPORT_GetHelloHandle *ghh = cls;
1473 GNUNET_assert (NULL != ghh->handle->my_hello);
1474 GNUNET_assert (GNUNET_SCHEDULER_NO_TASK != ghh->notify_task);
1475 ghh->notify_task = GNUNET_SCHEDULER_NO_TASK;
1476 ghh->rec (ghh->rec_cls,
1477 (const struct GNUNET_MessageHeader *) ghh->handle->my_hello);
1482 * Obtain the HELLO message for this peer. The callback given in this function
1483 * is never called synchronously.
1485 * @param handle connection to transport service
1486 * @param rec function to call with the HELLO, sender will be our peer
1487 * identity; message and sender will be NULL on timeout
1488 * (handshake with transport service pending/failed).
1489 * cost estimate will be 0.
1490 * @param rec_cls closure for @a rec
1491 * @return handle to cancel the operation
1493 struct GNUNET_TRANSPORT_GetHelloHandle *
1494 GNUNET_TRANSPORT_get_hello (struct GNUNET_TRANSPORT_Handle *handle,
1495 GNUNET_TRANSPORT_HelloUpdateCallback rec,
1498 struct GNUNET_TRANSPORT_GetHelloHandle *hwl;
1500 hwl = GNUNET_new (struct GNUNET_TRANSPORT_GetHelloHandle);
1502 hwl->rec_cls = rec_cls;
1503 hwl->handle = handle;
1504 GNUNET_CONTAINER_DLL_insert (handle->hwl_head, handle->hwl_tail, hwl);
1505 if (handle->my_hello != NULL)
1506 hwl->notify_task = GNUNET_SCHEDULER_add_now (&call_hello_update_cb_async,
1513 * Stop receiving updates about changes to our HELLO message.
1515 * @param ghh handle to cancel
1518 GNUNET_TRANSPORT_get_hello_cancel (struct GNUNET_TRANSPORT_GetHelloHandle *ghh)
1520 struct GNUNET_TRANSPORT_Handle *handle = ghh->handle;
1522 if (GNUNET_SCHEDULER_NO_TASK != ghh->notify_task)
1523 GNUNET_SCHEDULER_cancel (ghh->notify_task);
1524 GNUNET_CONTAINER_DLL_remove (handle->hwl_head, handle->hwl_tail, ghh);
1530 * Connect to the transport service. Note that the connection may
1531 * complete (or fail) asynchronously.
1533 * @param cfg configuration to use
1534 * @param self our own identity (API should check that it matches
1535 * the identity found by transport), or NULL (no check)
1536 * @param cls closure for the callbacks
1537 * @param rec receive function to call
1538 * @param nc function to call on connect events
1539 * @param nd function to call on disconnect events
1540 * @return NULL on error
1542 struct GNUNET_TRANSPORT_Handle *
1543 GNUNET_TRANSPORT_connect (const struct GNUNET_CONFIGURATION_Handle *cfg,
1544 const struct GNUNET_PeerIdentity *self, void *cls,
1545 GNUNET_TRANSPORT_ReceiveCallback rec,
1546 GNUNET_TRANSPORT_NotifyConnect nc,
1547 GNUNET_TRANSPORT_NotifyDisconnect nd)
1549 return GNUNET_TRANSPORT_connect2 (cfg, self, cls,
1555 * Connect to the transport service. Note that the connection may
1556 * complete (or fail) asynchronously.
1558 * @param cfg configuration to use
1559 * @param self our own identity (API should check that it matches
1560 * the identity found by transport), or NULL (no check)
1561 * @param cls closure for the callbacks
1562 * @param rec receive function to call
1563 * @param nc function to call on connect events
1564 * @param nd function to call on disconnect events
1565 * @param neb function to call if we have excess bandwidth to a peer
1566 * @return NULL on error
1568 struct GNUNET_TRANSPORT_Handle *
1569 GNUNET_TRANSPORT_connect2 (const struct GNUNET_CONFIGURATION_Handle *cfg,
1570 const struct GNUNET_PeerIdentity *self, void *cls,
1571 GNUNET_TRANSPORT_ReceiveCallback rec,
1572 GNUNET_TRANSPORT_NotifyConnect nc,
1573 GNUNET_TRANSPORT_NotifyDisconnect nd,
1574 GNUNET_TRANSPORT_NotifyExcessBandwidth neb)
1576 struct GNUNET_TRANSPORT_Handle *ret;
1578 ret = GNUNET_new (struct GNUNET_TRANSPORT_Handle);
1582 ret->check_self = GNUNET_YES;
1590 ret->reconnect_delay = GNUNET_TIME_UNIT_ZERO;
1591 LOG (GNUNET_ERROR_TYPE_DEBUG,
1592 "Connecting to transport service.\n");
1593 ret->client = GNUNET_CLIENT_connect ("transport", cfg);
1594 if (NULL == ret->client)
1600 GNUNET_CONTAINER_multipeermap_create (STARTING_NEIGHBOURS_SIZE,
1603 GNUNET_CONTAINER_heap_create (GNUNET_CONTAINER_HEAP_ORDER_MIN);
1604 schedule_control_transmit (ret, sizeof (struct StartMessage),
1611 * Disconnect from the transport service.
1613 * @param handle handle to the service as returned from #GNUNET_TRANSPORT_connect()
1616 GNUNET_TRANSPORT_disconnect (struct GNUNET_TRANSPORT_Handle *handle)
1618 LOG (GNUNET_ERROR_TYPE_DEBUG,
1619 "Transport disconnect called!\n");
1620 /* this disconnects all neighbours... */
1621 if (handle->reconnect_task == GNUNET_SCHEDULER_NO_TASK)
1622 disconnect_and_schedule_reconnect (handle);
1623 /* and now we stop trying to connect again... */
1624 if (handle->reconnect_task != GNUNET_SCHEDULER_NO_TASK)
1626 GNUNET_SCHEDULER_cancel (handle->reconnect_task);
1627 handle->reconnect_task = GNUNET_SCHEDULER_NO_TASK;
1629 GNUNET_CONTAINER_multipeermap_destroy (handle->neighbours);
1630 handle->neighbours = NULL;
1631 if (handle->quota_task != GNUNET_SCHEDULER_NO_TASK)
1633 GNUNET_SCHEDULER_cancel (handle->quota_task);
1634 handle->quota_task = GNUNET_SCHEDULER_NO_TASK;
1636 GNUNET_free_non_null (handle->my_hello);
1637 handle->my_hello = NULL;
1638 GNUNET_assert (NULL == handle->tc_head);
1639 GNUNET_assert (NULL == handle->tc_tail);
1640 GNUNET_assert (NULL == handle->hwl_head);
1641 GNUNET_assert (NULL == handle->hwl_tail);
1642 GNUNET_CONTAINER_heap_destroy (handle->ready_heap);
1643 handle->ready_heap = NULL;
1644 GNUNET_free (handle);
1649 * Check if we could queue a message of the given size for
1650 * transmission. The transport service will take both its
1651 * internal buffers and bandwidth limits imposed by the
1652 * other peer into consideration when answering this query.
1654 * @param handle connection to transport service
1655 * @param target who should receive the message
1656 * @param size how big is the message we want to transmit?
1657 * @param timeout after how long should we give up (and call
1658 * notify with buf NULL and size 0)?
1659 * @param notify function to call when we are ready to
1660 * send such a message
1661 * @param notify_cls closure for @a notify
1662 * @return NULL if someone else is already waiting to be notified
1663 * non-NULL if the notify callback was queued (can be used to cancel
1664 * using #GNUNET_TRANSPORT_notify_transmit_ready_cancel)
1666 struct GNUNET_TRANSPORT_TransmitHandle *
1667 GNUNET_TRANSPORT_notify_transmit_ready (struct GNUNET_TRANSPORT_Handle *handle,
1668 const struct GNUNET_PeerIdentity *target,
1670 struct GNUNET_TIME_Relative timeout,
1671 GNUNET_TRANSPORT_TransmitReadyNotify notify,
1674 struct Neighbour *n;
1675 struct GNUNET_TRANSPORT_TransmitHandle *th;
1676 struct GNUNET_TIME_Relative delay;
1678 n = neighbour_find (handle, target);
1681 /* use GNUNET_TRANSPORT_try_connect first, only use this function
1682 * once a connection has been established */
1688 /* attempt to send two messages at the same time to the same peer */
1692 GNUNET_assert (NULL == n->hn);
1693 th = GNUNET_new (struct GNUNET_TRANSPORT_TransmitHandle);
1695 th->notify = notify;
1696 th->notify_cls = notify_cls;
1697 th->timeout = GNUNET_TIME_relative_to_absolute (timeout);
1698 th->notify_size = size;
1700 /* calculate when our transmission should be ready */
1701 delay = GNUNET_BANDWIDTH_tracker_get_delay (&n->out_tracker, size + n->traffic_overhead);
1702 n->traffic_overhead = 0;
1703 if (delay.rel_value_us > timeout.rel_value_us)
1704 delay.rel_value_us = 0; /* notify immediately (with failure) */
1705 LOG (GNUNET_ERROR_TYPE_DEBUG,
1706 "Bandwidth tracker allows next transmission to peer %s in %s\n",
1707 GNUNET_i2s (target),
1708 GNUNET_STRINGS_relative_time_to_string (delay, GNUNET_YES));
1709 n->hn = GNUNET_CONTAINER_heap_insert (handle->ready_heap, n, delay.rel_value_us);
1710 schedule_transmission (handle);
1716 * Cancel the specified transmission-ready notification.
1718 * @param th handle returned from #GNUNET_TRANSPORT_notify_transmit_ready()
1721 GNUNET_TRANSPORT_notify_transmit_ready_cancel (struct GNUNET_TRANSPORT_TransmitHandle *th)
1723 struct Neighbour *n;
1725 GNUNET_assert (NULL == th->next);
1726 GNUNET_assert (NULL == th->prev);
1728 GNUNET_assert (th == n->th);
1732 GNUNET_CONTAINER_heap_remove_node (n->hn);
1737 GNUNET_assert (GNUNET_SCHEDULER_NO_TASK != th->timeout_task);
1738 GNUNET_SCHEDULER_cancel (th->timeout_task);
1739 th->timeout_task = GNUNET_SCHEDULER_NO_TASK;
1745 /* end of transport_api.c */