2 This file is part of GNUnet.
3 (C) 2009, 2010, 2011 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.
10 GNUnet is distributed in the hope that it will be useful, but
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
27 * - adjust testcases to use new 'try connect' style (should be easy, breaks API compatibility!)
28 * - adjust core service to use new 'try connect' style (should be MUCH nicer there as well!)
32 #include "gnunet_constants.h"
33 #include "gnunet_bandwidth_lib.h"
34 #include "gnunet_client_lib.h"
35 #include "gnunet_constants.h"
36 #include "gnunet_container_lib.h"
37 #include "gnunet_arm_service.h"
38 #include "gnunet_hello_lib.h"
39 #include "gnunet_protocols.h"
40 #include "gnunet_server_lib.h"
41 #include "gnunet_time_lib.h"
42 #include "gnunet_transport_service.h"
43 #include "transport.h"
45 #define LOG(kind,...) GNUNET_log_from (kind, "transport-api",__VA_ARGS__)
48 * How large to start with for the hashmap of neighbours.
50 #define STARTING_NEIGHBOURS_SIZE 16
53 * Handle for a message that should be transmitted to the service.
54 * Used for both control messages and normal messages.
56 struct GNUNET_TRANSPORT_TransmitHandle
60 * We keep all requests in a DLL.
62 struct GNUNET_TRANSPORT_TransmitHandle *next;
65 * We keep all requests in a DLL.
67 struct GNUNET_TRANSPORT_TransmitHandle *prev;
70 * Neighbour for this handle, NULL for control messages.
72 struct Neighbour *neighbour;
75 * Function to call when notify_size bytes are available
78 GNUNET_CONNECTION_TransmitReadyNotify notify;
86 * Timeout for this request, 0 for control messages.
88 struct GNUNET_TIME_Absolute timeout;
91 * Task to trigger request timeout if the request is stalled due to
94 GNUNET_SCHEDULER_TaskIdentifier timeout_task;
97 * How many bytes is our notify callback waiting for?
102 * How important is this message? Not used for control messages.
110 * Entry in hash table of all of our current neighbours.
115 * Overall transport handle.
117 struct GNUNET_TRANSPORT_Handle *h;
120 * Active transmit handle or NULL.
122 struct GNUNET_TRANSPORT_TransmitHandle *th;
125 * Identity of this neighbour.
127 struct GNUNET_PeerIdentity id;
130 * Outbound bandwidh tracker.
132 struct GNUNET_BANDWIDTH_Tracker out_tracker;
135 * Entry in our readyness heap (which is sorted by 'next_ready'
136 * value). NULL if there is no pending transmission request for
137 * this neighbour or if we're waiting for 'is_ready' to become
138 * true AFTER the 'out_tracker' suggested that this peer's quota
139 * has been satisfied (so once 'is_ready' goes to GNUNET_YES,
140 * we should immediately go back into the heap).
142 struct GNUNET_CONTAINER_HeapNode *hn;
145 * Is this peer currently ready to receive a message?
153 * Linked list of functions to call whenever our HELLO is updated.
155 struct GNUNET_TRANSPORT_GetHelloHandle
159 * This is a doubly linked list.
161 struct GNUNET_TRANSPORT_GetHelloHandle *next;
164 * This is a doubly linked list.
166 struct GNUNET_TRANSPORT_GetHelloHandle *prev;
171 struct GNUNET_TRANSPORT_Handle *handle;
174 * Callback to call once we got our HELLO.
176 GNUNET_TRANSPORT_HelloUpdateCallback rec;
187 * Handle for the transport service (includes all of the
188 * state for the transport service).
190 struct GNUNET_TRANSPORT_Handle
194 * Closure for the callbacks.
199 * Function to call for received data.
201 GNUNET_TRANSPORT_ReceiveCallback rec;
204 * function to call on connect events
206 GNUNET_TRANSPORT_NotifyConnect nc_cb;
209 * function to call on disconnect events
211 GNUNET_TRANSPORT_NotifyDisconnect nd_cb;
214 * Head of DLL of control messages.
216 struct GNUNET_TRANSPORT_TransmitHandle *control_head;
219 * Tail of DLL of control messages.
221 struct GNUNET_TRANSPORT_TransmitHandle *control_tail;
224 * The current HELLO message for this peer. Updated
225 * whenever transports change their addresses.
227 struct GNUNET_HELLO_Message *my_hello;
230 * My client connection to the transport service.
232 struct GNUNET_CLIENT_Connection *client;
235 * Handle to our registration with the client for notification.
237 struct GNUNET_CLIENT_TransmitHandle *cth;
240 * Linked list of pending requests for our HELLO.
242 struct GNUNET_TRANSPORT_GetHelloHandle *hwl_head;
245 * Linked list of pending requests for our HELLO.
247 struct GNUNET_TRANSPORT_GetHelloHandle *hwl_tail;
252 const struct GNUNET_CONFIGURATION_Handle *cfg;
255 * Hash map of the current connected neighbours of this peer.
256 * Maps peer identities to 'struct Neighbour' entries.
258 struct GNUNET_CONTAINER_MultiHashMap *neighbours;
261 * Heap sorting peers with pending messages by the timestamps that
262 * specify when we could next send a message to the respective peer.
263 * Excludes control messages (which can always go out immediately).
264 * Maps time stamps to 'struct Neighbour' entries.
266 struct GNUNET_CONTAINER_Heap *ready_heap;
269 * Peer identity as assumed by this process, or all zeros.
271 struct GNUNET_PeerIdentity self;
274 * ID of the task trying to reconnect to the service.
276 GNUNET_SCHEDULER_TaskIdentifier reconnect_task;
279 * ID of the task trying to trigger transmission for a peer while
280 * maintaining bandwidth quotas. In use if there are no control
281 * messages and the smallest entry in the 'ready_heap' has a time
282 * stamp in the future.
284 GNUNET_SCHEDULER_TaskIdentifier quota_task;
287 * Delay until we try to reconnect.
289 struct GNUNET_TIME_Relative reconnect_delay;
292 * Should we check that 'self' matches what the service thinks?
293 * (if GNUNET_NO, then 'self' is all zeros!).
300 * Schedule the task to send one message, either from the control
301 * list or the peer message queues to the service.
303 * @param h transport service to schedule a transmission for
306 schedule_transmission (struct GNUNET_TRANSPORT_Handle *h);
310 * Function that will schedule the job that will try
311 * to connect us again to the client.
313 * @param h transport service to reconnect
316 disconnect_and_schedule_reconnect (struct GNUNET_TRANSPORT_Handle *h);
320 * Get the neighbour list entry for the given peer
322 * @param h our context
323 * @param peer peer to look up
324 * @return NULL if no such peer entry exists
326 static struct Neighbour *
327 neighbour_find (struct GNUNET_TRANSPORT_Handle *h,
328 const struct GNUNET_PeerIdentity *peer)
330 return GNUNET_CONTAINER_multihashmap_get (h->neighbours, &peer->hashPubKey);
335 * Add neighbour to our list
337 * @return NULL if this API is currently disconnecting from the service
339 static struct Neighbour *
340 neighbour_add (struct GNUNET_TRANSPORT_Handle *h,
341 const struct GNUNET_PeerIdentity *pid)
345 LOG (GNUNET_ERROR_TYPE_DEBUG, "Creating entry for neighbour `%4s'.\n",
347 n = GNUNET_malloc (sizeof (struct Neighbour));
350 n->is_ready = GNUNET_YES;
351 GNUNET_BANDWIDTH_tracker_init (&n->out_tracker,
352 GNUNET_CONSTANTS_DEFAULT_BW_IN_OUT,
353 MAX_BANDWIDTH_CARRY_S);
354 GNUNET_assert (GNUNET_OK ==
355 GNUNET_CONTAINER_multihashmap_put (h->neighbours,
357 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
363 * Iterator over hash map entries, for deleting state of a neighbour.
365 * @param cls the 'struct GNUNET_TRANSPORT_Handle*'
366 * @param key peer identity
367 * @param value value in the hash map, the neighbour entry to delete
368 * @return GNUNET_YES if we should continue to
373 neighbour_delete (void *cls, const struct GNUNET_HashCode * key, void *value)
375 struct GNUNET_TRANSPORT_Handle *handle = cls;
376 struct Neighbour *n = value;
378 if (NULL != handle->nd_cb)
379 handle->nd_cb (handle->cls, &n->id);
380 GNUNET_assert (NULL == n->th);
381 GNUNET_assert (NULL == n->hn);
382 GNUNET_assert (GNUNET_YES ==
383 GNUNET_CONTAINER_multihashmap_remove (handle->neighbours, key,
391 * Function we use for handling incoming messages.
393 * @param cls closure (struct GNUNET_TRANSPORT_Handle *)
394 * @param msg message received, NULL on timeout or fatal error
397 demultiplexer (void *cls, const struct GNUNET_MessageHeader *msg)
399 struct GNUNET_TRANSPORT_Handle *h = cls;
400 const struct DisconnectInfoMessage *dim;
401 const struct ConnectInfoMessage *cim;
402 const struct InboundMessage *im;
403 const struct GNUNET_MessageHeader *imm;
404 const struct SendOkMessage *okm;
405 const struct QuotaSetMessage *qm;
406 const struct GNUNET_ATS_Information *ats;
407 struct GNUNET_TRANSPORT_GetHelloHandle *hwl;
408 struct GNUNET_TRANSPORT_GetHelloHandle *next_hwl;
410 struct GNUNET_PeerIdentity me;
414 GNUNET_assert (h->client != NULL);
417 LOG (GNUNET_ERROR_TYPE_DEBUG,
418 "Error receiving from transport service, disconnecting temporarily.\n");
419 disconnect_and_schedule_reconnect (h);
422 GNUNET_CLIENT_receive (h->client, &demultiplexer, h,
423 GNUNET_TIME_UNIT_FOREVER_REL);
424 size = ntohs (msg->size);
425 switch (ntohs (msg->type))
427 case GNUNET_MESSAGE_TYPE_HELLO:
429 GNUNET_HELLO_get_id ((const struct GNUNET_HELLO_Message *) msg, &me))
434 LOG (GNUNET_ERROR_TYPE_DEBUG,
435 "Receiving (my own) `%s' message, I am `%4s'.\n", "HELLO",
437 GNUNET_free_non_null (h->my_hello);
439 if (size < sizeof (struct GNUNET_MessageHeader))
444 h->my_hello = GNUNET_malloc (size);
445 memcpy (h->my_hello, msg, size);
449 next_hwl = hwl->next;
450 hwl->rec (hwl->rec_cls,
451 (const struct GNUNET_MessageHeader *) h->my_hello);
455 case GNUNET_MESSAGE_TYPE_TRANSPORT_CONNECT:
456 if (size < sizeof (struct ConnectInfoMessage))
461 cim = (const struct ConnectInfoMessage *) msg;
462 ats_count = ntohl (cim->ats_count);
464 sizeof (struct ConnectInfoMessage) +
465 ats_count * sizeof (struct GNUNET_ATS_Information))
470 ats = (const struct GNUNET_ATS_Information *) &cim[1];
471 LOG (GNUNET_ERROR_TYPE_DEBUG, "Receiving `%s' message for `%4s'.\n",
472 "CONNECT", GNUNET_i2s (&cim->id));
473 n = neighbour_find (h, &cim->id);
479 n = neighbour_add (h, &cim->id);
480 if (h->nc_cb != NULL)
481 h->nc_cb (h->cls, &n->id, ats, ats_count);
483 case GNUNET_MESSAGE_TYPE_TRANSPORT_DISCONNECT:
484 if (size != sizeof (struct DisconnectInfoMessage))
489 dim = (const struct DisconnectInfoMessage *) msg;
490 GNUNET_break (ntohl (dim->reserved) == 0);
491 LOG (GNUNET_ERROR_TYPE_DEBUG, "Receiving `%s' message for `%4s'.\n",
492 "DISCONNECT", GNUNET_i2s (&dim->peer));
493 n = neighbour_find (h, &dim->peer);
499 neighbour_delete (h, &dim->peer.hashPubKey, n);
501 case GNUNET_MESSAGE_TYPE_TRANSPORT_SEND_OK:
502 if (size != sizeof (struct SendOkMessage))
507 okm = (const struct SendOkMessage *) msg;
508 LOG (GNUNET_ERROR_TYPE_DEBUG, "Receiving `%s' message, transmission %s.\n",
509 "SEND_OK", ntohl (okm->success) == GNUNET_OK ? "succeeded" : "failed");
510 n = neighbour_find (h, &okm->peer);
513 GNUNET_break (GNUNET_NO == n->is_ready);
514 n->is_ready = GNUNET_YES;
515 if ((n->th != NULL) && (n->hn == NULL))
517 GNUNET_assert (GNUNET_SCHEDULER_NO_TASK != n->th->timeout_task);
518 GNUNET_SCHEDULER_cancel (n->th->timeout_task);
519 n->th->timeout_task = GNUNET_SCHEDULER_NO_TASK;
520 /* we've been waiting for this (congestion, not quota,
521 * caused delayed transmission) */
522 n->hn = GNUNET_CONTAINER_heap_insert (h->ready_heap, n, 0);
523 schedule_transmission (h);
526 case GNUNET_MESSAGE_TYPE_TRANSPORT_RECV:
527 LOG (GNUNET_ERROR_TYPE_DEBUG, "Receiving `%s' message.\n", "RECV");
529 sizeof (struct InboundMessage) + sizeof (struct GNUNET_MessageHeader))
534 im = (const struct InboundMessage *) msg;
535 ats_count = ntohl (im->ats_count);
536 ats = (const struct GNUNET_ATS_Information *) &im[1];
537 imm = (const struct GNUNET_MessageHeader *) &ats[ats_count];
538 if (ntohs (imm->size) + sizeof (struct InboundMessage) +
539 ats_count * sizeof (struct GNUNET_ATS_Information) != size)
544 LOG (GNUNET_ERROR_TYPE_DEBUG, "Received message of type %u from `%4s'.\n",
545 ntohs (imm->type), GNUNET_i2s (&im->peer));
546 n = neighbour_find (h, &im->peer);
553 h->rec (h->cls, &im->peer, imm, ats, ats_count);
555 case GNUNET_MESSAGE_TYPE_TRANSPORT_SET_QUOTA:
556 LOG (GNUNET_ERROR_TYPE_DEBUG, "Receiving `%s' message.\n", "SET_QUOTA");
557 if (size != sizeof (struct QuotaSetMessage))
562 qm = (const struct QuotaSetMessage *) msg;
563 n = neighbour_find (h, &qm->peer);
566 GNUNET_BANDWIDTH_tracker_update_quota (&n->out_tracker, qm->quota);
569 LOG (GNUNET_ERROR_TYPE_ERROR,
570 _("Received unexpected message of type %u in %s:%u\n"),
571 ntohs (msg->type), __FILE__, __LINE__);
579 * A transmission request could not be satisfied because of
580 * network congestion. Notify the initiator and clean up.
582 * @param cls the 'struct GNUNET_TRANSPORT_TransmitHandle'
583 * @param tc scheduler context
586 timeout_request_due_to_congestion (void *cls,
587 const struct GNUNET_SCHEDULER_TaskContext
590 struct GNUNET_TRANSPORT_TransmitHandle *th = cls;
591 struct Neighbour *n = th->neighbour;
593 n->th->timeout_task = GNUNET_SCHEDULER_NO_TASK;
594 GNUNET_assert (th == n->th);
595 GNUNET_assert (NULL == n->hn);
597 th->notify (th->notify_cls, 0, NULL);
603 * Transmit message(s) to service.
605 * @param cls handle to transport
606 * @param size number of bytes available in buf
607 * @param buf where to copy the message
608 * @return number of bytes copied to buf
611 transport_notify_ready (void *cls, size_t size, void *buf)
613 struct GNUNET_TRANSPORT_Handle *h = cls;
614 struct GNUNET_TRANSPORT_TransmitHandle *th;
617 struct OutboundMessage obm;
622 GNUNET_assert (NULL != h->client);
626 /* transmission failed */
627 disconnect_and_schedule_reconnect (h);
633 /* first send control messages */
634 while ((NULL != (th = h->control_head)) && (th->notify_size <= size))
636 GNUNET_CONTAINER_DLL_remove (h->control_head, h->control_tail, th);
637 nret = th->notify (th->notify_cls, size, &cbuf[ret]);
638 LOG (GNUNET_ERROR_TYPE_DEBUG, "Added %u bytes of control message at %u\n",
645 /* then, if possible and no control messages pending, send data messages */
646 while ((NULL == h->control_head) &&
647 (NULL != (n = GNUNET_CONTAINER_heap_peek (h->ready_heap))))
649 if (GNUNET_YES != n->is_ready)
651 /* peer not ready, wait for notification! */
652 GNUNET_assert (n == GNUNET_CONTAINER_heap_remove_root (h->ready_heap));
654 GNUNET_assert (GNUNET_SCHEDULER_NO_TASK == n->th->timeout_task);
655 n->th->timeout_task =
656 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_absolute_get_remaining
658 &timeout_request_due_to_congestion,
663 if (th->notify_size + sizeof (struct OutboundMessage) > size)
664 break; /* does not fit */
665 if (GNUNET_BANDWIDTH_tracker_get_delay
666 (&n->out_tracker, th->notify_size).rel_value > 0)
667 break; /* too early */
668 GNUNET_assert (n == GNUNET_CONTAINER_heap_remove_root (h->ready_heap));
671 n->is_ready = GNUNET_NO;
672 GNUNET_assert (size >= sizeof (struct OutboundMessage));
674 th->notify (th->notify_cls, size - sizeof (struct OutboundMessage),
675 &cbuf[ret + sizeof (struct OutboundMessage)]);
676 GNUNET_assert (mret <= size - sizeof (struct OutboundMessage));
679 GNUNET_assert (mret + sizeof (struct OutboundMessage) <
680 GNUNET_SERVER_MAX_MESSAGE_SIZE);
681 obm.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SEND);
682 obm.header.size = htons (mret + sizeof (struct OutboundMessage));
683 obm.priority = htonl (th->priority);
685 GNUNET_TIME_relative_hton (GNUNET_TIME_absolute_get_remaining
688 memcpy (&cbuf[ret], &obm, sizeof (struct OutboundMessage));
689 ret += (mret + sizeof (struct OutboundMessage));
690 size -= (mret + sizeof (struct OutboundMessage));
691 GNUNET_BANDWIDTH_tracker_consume (&n->out_tracker, mret);
695 /* if there are more pending messages, try to schedule those */
696 schedule_transmission (h);
697 LOG (GNUNET_ERROR_TYPE_DEBUG, "Transmitting %u bytes to transport service\n",
704 * Schedule the task to send one message, either from the control
705 * list or the peer message queues to the service.
707 * @param cls transport service to schedule a transmission for
708 * @param tc scheduler context
711 schedule_transmission_task (void *cls,
712 const struct GNUNET_SCHEDULER_TaskContext *tc)
714 struct GNUNET_TRANSPORT_Handle *h = cls;
716 struct GNUNET_TRANSPORT_TransmitHandle *th;
719 h->quota_task = GNUNET_SCHEDULER_NO_TASK;
720 GNUNET_assert (NULL != h->client);
721 /* destroy all requests that have timed out */
722 while ((NULL != (n = GNUNET_CONTAINER_heap_peek (h->ready_heap))) &&
723 (GNUNET_TIME_absolute_get_remaining (n->th->timeout).rel_value == 0))
725 /* notify client that the request could not be satisfied within
726 * the given time constraints */
729 GNUNET_assert (n == GNUNET_CONTAINER_heap_remove_root (h->ready_heap));
731 LOG (GNUNET_ERROR_TYPE_DEBUG,
732 "Signalling timeout for transmission to peer %s due to congestion\n",
733 GNUNET_i2s (&n->id));
734 GNUNET_assert (0 == th->notify (th->notify_cls, 0, NULL));
739 if (NULL != h->control_head)
741 size = h->control_head->notify_size;
745 n = GNUNET_CONTAINER_heap_peek (h->ready_heap);
747 return; /* no pending messages */
748 size = n->th->notify_size + sizeof (struct OutboundMessage);
750 LOG (GNUNET_ERROR_TYPE_DEBUG, "Calling notify_transmit_ready\n");
752 GNUNET_CLIENT_notify_transmit_ready (h->client, size,
753 GNUNET_TIME_UNIT_FOREVER_REL,
754 GNUNET_NO, &transport_notify_ready,
756 GNUNET_assert (NULL != h->cth);
761 * Schedule the task to send one message, either from the control
762 * list or the peer message queues to the service.
764 * @param h transport service to schedule a transmission for
767 schedule_transmission (struct GNUNET_TRANSPORT_Handle *h)
769 struct GNUNET_TIME_Relative delay;
772 GNUNET_assert (NULL != h->client);
773 if (h->quota_task != GNUNET_SCHEDULER_NO_TASK)
775 GNUNET_SCHEDULER_cancel (h->quota_task);
776 h->quota_task = GNUNET_SCHEDULER_NO_TASK;
778 if (NULL != h->control_head)
779 delay = GNUNET_TIME_UNIT_ZERO;
780 else if (NULL != (n = GNUNET_CONTAINER_heap_peek (h->ready_heap)))
782 GNUNET_BANDWIDTH_tracker_get_delay (&n->out_tracker,
785 return; /* no work to be done */
786 LOG (GNUNET_ERROR_TYPE_DEBUG,
787 "Scheduling next transmission to service in %llu ms\n",
788 (unsigned long long) delay.rel_value);
790 GNUNET_SCHEDULER_add_delayed (delay, &schedule_transmission_task, h);
795 * Queue control request for transmission to the transport
798 * @param h handle to the transport service
799 * @param size number of bytes to be transmitted
800 * @param notify function to call to get the content
801 * @param notify_cls closure for notify
804 schedule_control_transmit (struct GNUNET_TRANSPORT_Handle *h, size_t size,
805 GNUNET_CONNECTION_TransmitReadyNotify notify,
808 struct GNUNET_TRANSPORT_TransmitHandle *th;
810 LOG (GNUNET_ERROR_TYPE_DEBUG, "Control transmit of %u bytes requested\n",
812 th = GNUNET_malloc (sizeof (struct GNUNET_TRANSPORT_TransmitHandle));
814 th->notify_cls = notify_cls;
815 th->notify_size = size;
816 GNUNET_CONTAINER_DLL_insert_tail (h->control_head, h->control_tail, th);
817 schedule_transmission (h);
822 * Transmit START message to service.
825 * @param size number of bytes available in buf
826 * @param buf where to copy the message
827 * @return number of bytes copied to buf
830 send_start (void *cls, size_t size, void *buf)
832 struct GNUNET_TRANSPORT_Handle *h = cls;
833 struct StartMessage s;
838 /* Can only be shutdown, just give up */
839 LOG (GNUNET_ERROR_TYPE_DEBUG,
840 "Shutdown while trying to transmit `%s' request.\n", "START");
843 LOG (GNUNET_ERROR_TYPE_DEBUG, "Transmitting `%s' request.\n", "START");
844 GNUNET_assert (size >= sizeof (struct StartMessage));
845 s.header.size = htons (sizeof (struct StartMessage));
846 s.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_START);
852 s.options = htonl (options);
854 memcpy (buf, &s, sizeof (struct StartMessage));
855 GNUNET_CLIENT_receive (h->client, &demultiplexer, h,
856 GNUNET_TIME_UNIT_FOREVER_REL);
857 return sizeof (struct StartMessage);
862 * Try again to connect to transport service.
864 * @param cls the handle to the transport service
865 * @param tc scheduler context
868 reconnect (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
870 struct GNUNET_TRANSPORT_Handle *h = cls;
872 h->reconnect_task = GNUNET_SCHEDULER_NO_TASK;
873 if ((tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN) != 0)
875 /* shutdown, just give up */
878 LOG (GNUNET_ERROR_TYPE_DEBUG, "Connecting to transport service.\n");
879 GNUNET_assert (h->client == NULL);
880 GNUNET_assert (h->control_head == NULL);
881 GNUNET_assert (h->control_tail == NULL);
882 h->client = GNUNET_CLIENT_connect ("transport", h->cfg);
883 GNUNET_assert (h->client != NULL);
884 schedule_control_transmit (h, sizeof (struct StartMessage), &send_start, h);
889 * Function that will schedule the job that will try
890 * to connect us again to the client.
892 * @param h transport service to reconnect
895 disconnect_and_schedule_reconnect (struct GNUNET_TRANSPORT_Handle *h)
897 struct GNUNET_TRANSPORT_TransmitHandle *th;
899 GNUNET_assert (h->reconnect_task == GNUNET_SCHEDULER_NO_TASK);
902 GNUNET_CLIENT_notify_transmit_ready_cancel (h->cth);
905 if (NULL != h->client)
907 GNUNET_CLIENT_disconnect (h->client);
910 /* Forget about all neighbours that we used to be connected to */
911 GNUNET_CONTAINER_multihashmap_iterate (h->neighbours, &neighbour_delete, h);
912 if (h->quota_task != GNUNET_SCHEDULER_NO_TASK)
914 GNUNET_SCHEDULER_cancel (h->quota_task);
915 h->quota_task = GNUNET_SCHEDULER_NO_TASK;
917 while ((NULL != (th = h->control_head)))
919 GNUNET_CONTAINER_DLL_remove (h->control_head, h->control_tail, th);
920 th->notify (th->notify_cls, 0, NULL);
923 LOG (GNUNET_ERROR_TYPE_DEBUG,
924 "Scheduling task to reconnect to transport service in %llu ms.\n",
925 h->reconnect_delay.rel_value);
927 GNUNET_SCHEDULER_add_delayed (h->reconnect_delay, &reconnect, h);
928 if (h->reconnect_delay.rel_value == 0)
930 h->reconnect_delay = GNUNET_TIME_UNIT_MILLISECONDS;
934 h->reconnect_delay = GNUNET_TIME_relative_multiply (h->reconnect_delay, 2);
936 GNUNET_TIME_relative_min (GNUNET_TIME_UNIT_SECONDS, h->reconnect_delay);
942 * Send REQUEST_CONNECT message to the service.
944 * @param cls the 'struct GNUNET_PeerIdentity'
945 * @param size number of bytes available in buf
946 * @param buf where to copy the message
947 * @return number of bytes copied to buf
950 send_try_connect (void *cls, size_t size, void *buf)
952 struct GNUNET_PeerIdentity *pid = cls;
953 struct TransportRequestConnectMessage msg;
960 LOG (GNUNET_ERROR_TYPE_DEBUG,
961 "Transmitting `%s' request with respect to `%4s'.\n", "REQUEST_CONNECT",
963 GNUNET_assert (size >= sizeof (struct TransportRequestConnectMessage));
964 msg.header.size = htons (sizeof (struct TransportRequestConnectMessage));
965 msg.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_REQUEST_CONNECT);
966 msg.reserved = htonl (0);
968 memcpy (buf, &msg, sizeof (msg));
970 return sizeof (struct TransportRequestConnectMessage);
975 * Ask the transport service to establish a connection to
978 * @param handle connection to transport service
979 * @param target who we should try to connect to
982 GNUNET_TRANSPORT_try_connect (struct GNUNET_TRANSPORT_Handle *handle,
983 const struct GNUNET_PeerIdentity *target)
985 struct GNUNET_PeerIdentity *pid;
987 if (NULL == handle->client)
989 pid = GNUNET_malloc (sizeof (struct GNUNET_PeerIdentity));
991 schedule_control_transmit (handle,
992 sizeof (struct TransportRequestConnectMessage),
993 &send_try_connect, pid);
998 * Send HELLO message to the service.
1000 * @param cls the HELLO message to send
1001 * @param size number of bytes available in buf
1002 * @param buf where to copy the message
1003 * @return number of bytes copied to buf
1006 send_hello (void *cls, size_t size, void *buf)
1008 struct GNUNET_MessageHeader *msg = cls;
1013 LOG (GNUNET_ERROR_TYPE_DEBUG,
1014 "Timeout while trying to transmit `%s' request.\n", "HELLO");
1018 LOG (GNUNET_ERROR_TYPE_DEBUG, "Transmitting `%s' request.\n", "HELLO");
1019 ssize = ntohs (msg->size);
1020 GNUNET_assert (size >= ssize);
1021 memcpy (buf, msg, ssize);
1028 * Offer the transport service the HELLO of another peer. Note that
1029 * the transport service may just ignore this message if the HELLO is
1030 * malformed or useless due to our local configuration.
1032 * @param handle connection to transport service
1033 * @param hello the hello message
1034 * @param cont continuation to call when HELLO has been sent
1035 * @param cls closure for continuation
1039 GNUNET_TRANSPORT_offer_hello (struct GNUNET_TRANSPORT_Handle *handle,
1040 const struct GNUNET_MessageHeader *hello,
1041 GNUNET_SCHEDULER_Task cont, void *cls)
1044 struct GNUNET_PeerIdentity peer;
1045 struct GNUNET_MessageHeader *msg;
1047 if (NULL == handle->client)
1049 GNUNET_break (ntohs (hello->type) == GNUNET_MESSAGE_TYPE_HELLO);
1050 size = ntohs (hello->size);
1051 GNUNET_break (size >= sizeof (struct GNUNET_MessageHeader));
1053 GNUNET_HELLO_get_id ((const struct GNUNET_HELLO_Message *) hello, &peer))
1058 msg = GNUNET_malloc (size);
1059 memcpy (msg, hello, size);
1060 LOG (GNUNET_ERROR_TYPE_DEBUG,
1061 "Offering `%s' message of `%4s' to transport for validation.\n", "HELLO",
1062 GNUNET_i2s (&peer));
1063 schedule_control_transmit (handle, size, &send_hello, msg);
1068 * Obtain the HELLO message for this peer.
1070 * @param handle connection to transport service
1071 * @param rec function to call with the HELLO, sender will be our peer
1072 * identity; message and sender will be NULL on timeout
1073 * (handshake with transport service pending/failed).
1074 * cost estimate will be 0.
1075 * @param rec_cls closure for rec
1076 * @return handle to cancel the operation
1078 struct GNUNET_TRANSPORT_GetHelloHandle *
1079 GNUNET_TRANSPORT_get_hello (struct GNUNET_TRANSPORT_Handle *handle,
1080 GNUNET_TRANSPORT_HelloUpdateCallback rec,
1083 struct GNUNET_TRANSPORT_GetHelloHandle *hwl;
1085 hwl = GNUNET_malloc (sizeof (struct GNUNET_TRANSPORT_GetHelloHandle));
1087 hwl->rec_cls = rec_cls;
1088 hwl->handle = handle;
1089 GNUNET_CONTAINER_DLL_insert (handle->hwl_head, handle->hwl_tail, hwl);
1090 if (handle->my_hello != NULL)
1091 rec (rec_cls, (const struct GNUNET_MessageHeader *) handle->my_hello);
1097 * Stop receiving updates about changes to our HELLO message.
1099 * @param ghh handle to cancel
1102 GNUNET_TRANSPORT_get_hello_cancel (struct GNUNET_TRANSPORT_GetHelloHandle *ghh)
1104 struct GNUNET_TRANSPORT_Handle *handle = ghh->handle;
1106 GNUNET_CONTAINER_DLL_remove (handle->hwl_head, handle->hwl_tail, ghh);
1112 * Connect to the transport service. Note that the connection may
1113 * complete (or fail) asynchronously.
1115 * @param cfg configuration to use
1116 * @param self our own identity (API should check that it matches
1117 * the identity found by transport), or NULL (no check)
1118 * @param cls closure for the callbacks
1119 * @param rec receive function to call
1120 * @param nc function to call on connect events
1121 * @param nd function to call on disconnect events
1123 struct GNUNET_TRANSPORT_Handle *
1124 GNUNET_TRANSPORT_connect (const struct GNUNET_CONFIGURATION_Handle *cfg,
1125 const struct GNUNET_PeerIdentity *self, void *cls,
1126 GNUNET_TRANSPORT_ReceiveCallback rec,
1127 GNUNET_TRANSPORT_NotifyConnect nc,
1128 GNUNET_TRANSPORT_NotifyDisconnect nd)
1130 struct GNUNET_TRANSPORT_Handle *ret;
1132 ret = GNUNET_malloc (sizeof (struct GNUNET_TRANSPORT_Handle));
1136 ret->check_self = GNUNET_YES;
1143 ret->reconnect_delay = GNUNET_TIME_UNIT_ZERO;
1145 GNUNET_CONTAINER_multihashmap_create (STARTING_NEIGHBOURS_SIZE);
1147 GNUNET_CONTAINER_heap_create (GNUNET_CONTAINER_HEAP_ORDER_MIN);
1148 ret->reconnect_task = GNUNET_SCHEDULER_add_now (&reconnect, ret);
1154 * Disconnect from the transport service.
1156 * @param handle handle to the service as returned from GNUNET_TRANSPORT_connect
1159 GNUNET_TRANSPORT_disconnect (struct GNUNET_TRANSPORT_Handle *handle)
1161 LOG (GNUNET_ERROR_TYPE_DEBUG, "Transport disconnect called!\n");
1162 /* this disconnects all neighbours... */
1163 if (handle->reconnect_task == GNUNET_SCHEDULER_NO_TASK)
1164 disconnect_and_schedule_reconnect (handle);
1165 /* and now we stop trying to connect again... */
1166 if (handle->reconnect_task != GNUNET_SCHEDULER_NO_TASK)
1168 GNUNET_SCHEDULER_cancel (handle->reconnect_task);
1169 handle->reconnect_task = GNUNET_SCHEDULER_NO_TASK;
1171 GNUNET_CONTAINER_multihashmap_destroy (handle->neighbours);
1172 handle->neighbours = NULL;
1173 if (handle->quota_task != GNUNET_SCHEDULER_NO_TASK)
1175 GNUNET_SCHEDULER_cancel (handle->quota_task);
1176 handle->quota_task = GNUNET_SCHEDULER_NO_TASK;
1178 GNUNET_free_non_null (handle->my_hello);
1179 handle->my_hello = NULL;
1180 GNUNET_assert (handle->hwl_head == NULL);
1181 GNUNET_assert (handle->hwl_tail == NULL);
1182 GNUNET_CONTAINER_heap_destroy (handle->ready_heap);
1183 handle->ready_heap = NULL;
1184 GNUNET_free (handle);
1189 * Check if we could queue a message of the given size for
1190 * transmission. The transport service will take both its
1191 * internal buffers and bandwidth limits imposed by the
1192 * other peer into consideration when answering this query.
1194 * @param handle connection to transport service
1195 * @param target who should receive the message
1196 * @param size how big is the message we want to transmit?
1197 * @param priority how important is the message?
1198 * @param timeout after how long should we give up (and call
1199 * notify with buf NULL and size 0)?
1200 * @param notify function to call when we are ready to
1201 * send such a message
1202 * @param notify_cls closure for notify
1203 * @return NULL if someone else is already waiting to be notified
1204 * non-NULL if the notify callback was queued (can be used to cancel
1205 * using GNUNET_TRANSPORT_notify_transmit_ready_cancel)
1207 struct GNUNET_TRANSPORT_TransmitHandle *
1208 GNUNET_TRANSPORT_notify_transmit_ready (struct GNUNET_TRANSPORT_Handle *handle,
1209 const struct GNUNET_PeerIdentity
1210 *target, size_t size, uint32_t priority,
1211 struct GNUNET_TIME_Relative timeout,
1212 GNUNET_CONNECTION_TransmitReadyNotify
1213 notify, void *notify_cls)
1215 struct Neighbour *n;
1216 struct GNUNET_TRANSPORT_TransmitHandle *th;
1217 struct GNUNET_TIME_Relative delay;
1219 n = neighbour_find (handle, target);
1222 /* use GNUNET_TRANSPORT_try_connect first, only use this function
1223 * once a connection has been established */
1229 /* attempt to send two messages at the same time to the same peer */
1233 GNUNET_assert (NULL == n->hn);
1234 th = GNUNET_malloc (sizeof (struct GNUNET_TRANSPORT_TransmitHandle));
1236 th->notify = notify;
1237 th->notify_cls = notify_cls;
1238 th->timeout = GNUNET_TIME_relative_to_absolute (timeout);
1239 th->notify_size = size;
1240 th->priority = priority;
1242 /* calculate when our transmission should be ready */
1243 delay = GNUNET_BANDWIDTH_tracker_get_delay (&n->out_tracker, size);
1244 if (delay.rel_value > timeout.rel_value)
1245 delay.rel_value = 0; /* notify immediately (with failure) */
1246 LOG (GNUNET_ERROR_TYPE_DEBUG,
1247 "Bandwidth tracker allows next transmission to peer %s in %llu ms\n",
1248 GNUNET_i2s (target), (unsigned long long) delay.rel_value);
1249 n->hn = GNUNET_CONTAINER_heap_insert (handle->ready_heap, n, delay.rel_value);
1250 schedule_transmission (handle);
1256 * Cancel the specified transmission-ready notification.
1258 * @param th handle returned from GNUNET_TRANSPORT_notify_transmit_ready
1261 GNUNET_TRANSPORT_notify_transmit_ready_cancel (struct
1262 GNUNET_TRANSPORT_TransmitHandle
1265 struct Neighbour *n;
1267 GNUNET_assert (NULL == th->next);
1268 GNUNET_assert (NULL == th->prev);
1270 GNUNET_assert (th == n->th);
1274 GNUNET_CONTAINER_heap_remove_node (n->hn);
1279 GNUNET_assert (GNUNET_SCHEDULER_NO_TASK != th->timeout_task);
1280 GNUNET_SCHEDULER_cancel (th->timeout_task);
1281 th->timeout_task = GNUNET_SCHEDULER_NO_TASK;
1287 /* end of transport_api.c */