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 #if DEBUG_TRANSPORT_API
346 LOG (GNUNET_ERROR_TYPE_DEBUG, "Creating entry for neighbour `%4s'.\n",
349 n = GNUNET_malloc (sizeof (struct Neighbour));
352 n->is_ready = GNUNET_YES;
353 GNUNET_BANDWIDTH_tracker_init (&n->out_tracker,
354 GNUNET_CONSTANTS_DEFAULT_BW_IN_OUT,
355 MAX_BANDWIDTH_CARRY_S);
356 GNUNET_assert (GNUNET_OK ==
357 GNUNET_CONTAINER_multihashmap_put (h->neighbours,
359 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
365 * Iterator over hash map entries, for deleting state of a neighbour.
367 * @param cls the 'struct GNUNET_TRANSPORT_Handle*'
368 * @param key peer identity
369 * @param value value in the hash map, the neighbour entry to delete
370 * @return GNUNET_YES if we should continue to
375 neighbour_delete (void *cls, const GNUNET_HashCode * key, void *value)
377 struct GNUNET_TRANSPORT_Handle *handle = cls;
378 struct Neighbour *n = value;
380 if (NULL != handle->nd_cb)
381 handle->nd_cb (handle->cls, &n->id);
382 GNUNET_assert (NULL == n->th);
383 GNUNET_assert (NULL == n->hn);
384 GNUNET_assert (GNUNET_YES ==
385 GNUNET_CONTAINER_multihashmap_remove (handle->neighbours, key,
393 * Function we use for handling incoming messages.
395 * @param cls closure (struct GNUNET_TRANSPORT_Handle *)
396 * @param msg message received, NULL on timeout or fatal error
399 demultiplexer (void *cls, const struct GNUNET_MessageHeader *msg)
401 struct GNUNET_TRANSPORT_Handle *h = cls;
402 const struct DisconnectInfoMessage *dim;
403 const struct ConnectInfoMessage *cim;
404 const struct InboundMessage *im;
405 const struct GNUNET_MessageHeader *imm;
406 const struct SendOkMessage *okm;
407 const struct QuotaSetMessage *qm;
408 struct GNUNET_TRANSPORT_GetHelloHandle *hwl;
409 struct GNUNET_TRANSPORT_GetHelloHandle *next_hwl;
411 struct GNUNET_PeerIdentity me;
415 GNUNET_assert (h->client != NULL);
418 #if DEBUG_TRANSPORT_API
419 LOG (GNUNET_ERROR_TYPE_INFO,
420 "Error receiving from transport service, disconnecting temporarily.\n");
422 disconnect_and_schedule_reconnect (h);
425 GNUNET_CLIENT_receive (h->client, &demultiplexer, h,
426 GNUNET_TIME_UNIT_FOREVER_REL);
427 size = ntohs (msg->size);
428 switch (ntohs (msg->type))
430 case GNUNET_MESSAGE_TYPE_HELLO:
432 GNUNET_HELLO_get_id ((const struct GNUNET_HELLO_Message *) msg, &me))
437 #if DEBUG_TRANSPORT_API
438 LOG (GNUNET_ERROR_TYPE_DEBUG,
439 "Receiving (my own) `%s' message, I am `%4s'.\n", "HELLO",
442 GNUNET_free_non_null (h->my_hello);
444 if (size < sizeof (struct GNUNET_MessageHeader))
449 h->my_hello = GNUNET_malloc (size);
450 memcpy (h->my_hello, msg, size);
454 next_hwl = hwl->next;
455 hwl->rec (hwl->rec_cls,
456 (const struct GNUNET_MessageHeader *) h->my_hello);
460 case GNUNET_MESSAGE_TYPE_TRANSPORT_CONNECT:
461 if (size < sizeof (struct ConnectInfoMessage))
466 cim = (const struct ConnectInfoMessage *) msg;
467 ats_count = ntohl (cim->ats_count);
469 sizeof (struct ConnectInfoMessage) +
470 ats_count * sizeof (struct GNUNET_ATS_Information))
475 #if DEBUG_TRANSPORT_API
476 LOG (GNUNET_ERROR_TYPE_DEBUG, "Receiving `%s' message for `%4s'.\n",
477 "CONNECT", GNUNET_i2s (&cim->id));
479 n = neighbour_find (h, &cim->id);
485 n = neighbour_add (h, &cim->id);
486 if (h->nc_cb != NULL)
487 h->nc_cb (h->cls, &n->id, &cim->ats, ats_count);
489 case GNUNET_MESSAGE_TYPE_TRANSPORT_DISCONNECT:
490 if (size != sizeof (struct DisconnectInfoMessage))
495 dim = (const struct DisconnectInfoMessage *) msg;
496 GNUNET_break (ntohl (dim->reserved) == 0);
497 #if DEBUG_TRANSPORT_API_DISCONNECT
498 LOG (GNUNET_ERROR_TYPE_DEBUG, "Receiving `%s' message for `%4s'.\n",
499 "DISCONNECT", GNUNET_i2s (&dim->peer));
501 n = neighbour_find (h, &dim->peer);
507 neighbour_delete (h, &dim->peer.hashPubKey, n);
509 case GNUNET_MESSAGE_TYPE_TRANSPORT_SEND_OK:
510 if (size != sizeof (struct SendOkMessage))
515 okm = (const struct SendOkMessage *) msg;
516 #if DEBUG_TRANSPORT_API
517 LOG (GNUNET_ERROR_TYPE_DEBUG, "Receiving `%s' message, transmission %s.\n",
518 "SEND_OK", ntohl (okm->success) == GNUNET_OK ? "succeeded" : "failed");
520 n = neighbour_find (h, &okm->peer);
523 GNUNET_break (GNUNET_NO == n->is_ready);
524 n->is_ready = GNUNET_YES;
525 if ((n->th != NULL) && (n->hn == NULL))
527 GNUNET_assert (GNUNET_SCHEDULER_NO_TASK != n->th->timeout_task);
528 GNUNET_SCHEDULER_cancel (n->th->timeout_task);
529 n->th->timeout_task = GNUNET_SCHEDULER_NO_TASK;
530 /* we've been waiting for this (congestion, not quota,
531 * caused delayed transmission) */
532 n->hn = GNUNET_CONTAINER_heap_insert (h->ready_heap, n, 0);
533 schedule_transmission (h);
536 case GNUNET_MESSAGE_TYPE_TRANSPORT_RECV:
537 #if DEBUG_TRANSPORT_API
538 LOG (GNUNET_ERROR_TYPE_DEBUG, "Receiving `%s' message.\n", "RECV");
541 sizeof (struct InboundMessage) + sizeof (struct GNUNET_MessageHeader))
546 im = (const struct InboundMessage *) msg;
547 ats_count = ntohl (im->ats_count);
548 imm = (const struct GNUNET_MessageHeader *) &((&(im->ats))[ats_count + 1]);
550 if (ntohs (imm->size) + sizeof (struct InboundMessage) +
551 ats_count * sizeof (struct GNUNET_ATS_Information) != size)
556 #if DEBUG_TRANSPORT_API
557 LOG (GNUNET_ERROR_TYPE_DEBUG, "Received message of type %u from `%4s'.\n",
558 ntohs (imm->type), GNUNET_i2s (&im->peer));
560 n = neighbour_find (h, &im->peer);
567 h->rec (h->cls, &im->peer, imm, &im->ats, ats_count);
569 case GNUNET_MESSAGE_TYPE_TRANSPORT_SET_QUOTA:
570 #if DEBUG_TRANSPORT_API
571 LOG (GNUNET_ERROR_TYPE_DEBUG, "Receiving `%s' message.\n", "SET_QUOTA");
573 if (size != sizeof (struct QuotaSetMessage))
578 qm = (const struct QuotaSetMessage *) msg;
579 n = neighbour_find (h, &qm->peer);
582 GNUNET_BANDWIDTH_tracker_update_quota (&n->out_tracker, qm->quota);
585 LOG (GNUNET_ERROR_TYPE_ERROR,
586 _("Received unexpected message of type %u in %s:%u\n"),
587 ntohs (msg->type), __FILE__, __LINE__);
595 * A transmission request could not be satisfied because of
596 * network congestion. Notify the initiator and clean up.
598 * @param cls the 'struct GNUNET_TRANSPORT_TransmitHandle'
599 * @param tc scheduler context
602 timeout_request_due_to_congestion (void *cls,
603 const struct GNUNET_SCHEDULER_TaskContext
606 struct GNUNET_TRANSPORT_TransmitHandle *th = cls;
607 struct Neighbour *n = th->neighbour;
609 n->th->timeout_task = GNUNET_SCHEDULER_NO_TASK;
610 GNUNET_assert (th == n->th);
611 GNUNET_assert (NULL == n->hn);
613 th->notify (th->notify_cls, 0, NULL);
619 * Transmit message(s) to service.
621 * @param cls handle to transport
622 * @param size number of bytes available in buf
623 * @param buf where to copy the message
624 * @return number of bytes copied to buf
627 transport_notify_ready (void *cls, size_t size, void *buf)
629 struct GNUNET_TRANSPORT_Handle *h = cls;
630 struct GNUNET_TRANSPORT_TransmitHandle *th;
633 struct OutboundMessage obm;
638 GNUNET_assert (NULL != h->client);
642 /* transmission failed */
643 disconnect_and_schedule_reconnect (h);
649 /* first send control messages */
650 while ((NULL != (th = h->control_head)) && (th->notify_size <= size))
652 GNUNET_CONTAINER_DLL_remove (h->control_head, h->control_tail, th);
653 nret = th->notify (th->notify_cls, size, &cbuf[ret]);
654 #if DEBUG_TRANSPORT_API
655 LOG (GNUNET_ERROR_TYPE_DEBUG, "Added %u bytes of control message at %u\n",
663 /* then, if possible and no control messages pending, send data messages */
664 while ((NULL == h->control_head) &&
665 (NULL != (n = GNUNET_CONTAINER_heap_peek (h->ready_heap))))
667 if (GNUNET_YES != n->is_ready)
669 /* peer not ready, wait for notification! */
670 GNUNET_assert (n == GNUNET_CONTAINER_heap_remove_root (h->ready_heap));
672 GNUNET_assert (GNUNET_SCHEDULER_NO_TASK == n->th->timeout_task);
673 n->th->timeout_task =
674 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_absolute_get_remaining
676 &timeout_request_due_to_congestion,
681 if (th->notify_size + sizeof (struct OutboundMessage) > size)
682 break; /* does not fit */
683 if (GNUNET_BANDWIDTH_tracker_get_delay
684 (&n->out_tracker, th->notify_size).rel_value > 0)
685 break; /* too early */
686 GNUNET_assert (n == GNUNET_CONTAINER_heap_remove_root (h->ready_heap));
689 n->is_ready = GNUNET_NO;
690 GNUNET_assert (size >= sizeof (struct OutboundMessage));
692 th->notify (th->notify_cls, size - sizeof (struct OutboundMessage),
693 &cbuf[ret + sizeof (struct OutboundMessage)]);
694 GNUNET_assert (mret <= size - sizeof (struct OutboundMessage));
697 GNUNET_assert (mret + sizeof (struct OutboundMessage) <
698 GNUNET_SERVER_MAX_MESSAGE_SIZE);
699 obm.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SEND);
700 obm.header.size = htons (mret + sizeof (struct OutboundMessage));
701 obm.priority = htonl (th->priority);
703 GNUNET_TIME_relative_hton (GNUNET_TIME_absolute_get_remaining
706 memcpy (&cbuf[ret], &obm, sizeof (struct OutboundMessage));
707 ret += (mret + sizeof (struct OutboundMessage));
708 size -= (mret + sizeof (struct OutboundMessage));
709 GNUNET_BANDWIDTH_tracker_consume (&n->out_tracker, mret);
713 /* if there are more pending messages, try to schedule those */
714 schedule_transmission (h);
715 #if DEBUG_TRANSPORT_API
716 LOG (GNUNET_ERROR_TYPE_DEBUG, "Transmitting %u bytes to transport service\n",
724 * Schedule the task to send one message, either from the control
725 * list or the peer message queues to the service.
727 * @param cls transport service to schedule a transmission for
728 * @param tc scheduler context
731 schedule_transmission_task (void *cls,
732 const struct GNUNET_SCHEDULER_TaskContext *tc)
734 struct GNUNET_TRANSPORT_Handle *h = cls;
736 struct GNUNET_TRANSPORT_TransmitHandle *th;
739 h->quota_task = GNUNET_SCHEDULER_NO_TASK;
740 GNUNET_assert (NULL != h->client);
741 /* destroy all requests that have timed out */
742 while ((NULL != (n = GNUNET_CONTAINER_heap_peek (h->ready_heap))) &&
743 (GNUNET_TIME_absolute_get_remaining (n->th->timeout).rel_value == 0))
745 /* notify client that the request could not be satisfied within
746 * the given time constraints */
749 GNUNET_assert (n == GNUNET_CONTAINER_heap_remove_root (h->ready_heap));
751 #if DEBUG_TRANSPORT_API
752 LOG (GNUNET_ERROR_TYPE_DEBUG,
753 "Signalling timeout for transmission to peer %s due to congestion\n",
754 GNUNET_i2s (&n->id));
756 GNUNET_assert (0 == th->notify (th->notify_cls, 0, NULL));
761 if (NULL != h->control_head)
763 size = h->control_head->notify_size;
767 n = GNUNET_CONTAINER_heap_peek (h->ready_heap);
769 return; /* no pending messages */
770 size = n->th->notify_size + sizeof (struct OutboundMessage);
772 #if DEBUG_TRANSPORT_API
773 LOG (GNUNET_ERROR_TYPE_DEBUG, "Calling notify_transmit_ready\n");
776 GNUNET_CLIENT_notify_transmit_ready (h->client, size,
777 GNUNET_TIME_UNIT_FOREVER_REL,
778 GNUNET_NO, &transport_notify_ready,
780 GNUNET_assert (NULL != h->cth);
785 * Schedule the task to send one message, either from the control
786 * list or the peer message queues to the service.
788 * @param h transport service to schedule a transmission for
791 schedule_transmission (struct GNUNET_TRANSPORT_Handle *h)
793 struct GNUNET_TIME_Relative delay;
796 GNUNET_assert (NULL != h->client);
797 if (h->quota_task != GNUNET_SCHEDULER_NO_TASK)
799 GNUNET_SCHEDULER_cancel (h->quota_task);
800 h->quota_task = GNUNET_SCHEDULER_NO_TASK;
802 if (NULL != h->control_head)
803 delay = GNUNET_TIME_UNIT_ZERO;
804 else if (NULL != (n = GNUNET_CONTAINER_heap_peek (h->ready_heap)))
806 GNUNET_BANDWIDTH_tracker_get_delay (&n->out_tracker,
809 return; /* no work to be done */
810 #if DEBUG_TRANSPORT_API
811 LOG (GNUNET_ERROR_TYPE_DEBUG,
812 "Scheduling next transmission to service in %llu ms\n",
813 (unsigned long long) delay.rel_value);
816 GNUNET_SCHEDULER_add_delayed (delay, &schedule_transmission_task, h);
821 * Queue control request for transmission to the transport
824 * @param h handle to the transport service
825 * @param size number of bytes to be transmitted
826 * @param notify function to call to get the content
827 * @param notify_cls closure for notify
830 schedule_control_transmit (struct GNUNET_TRANSPORT_Handle *h, size_t size,
831 GNUNET_CONNECTION_TransmitReadyNotify notify,
834 struct GNUNET_TRANSPORT_TransmitHandle *th;
836 #if DEBUG_TRANSPORT_API
837 LOG (GNUNET_ERROR_TYPE_DEBUG, "Control transmit of %u bytes requested\n",
840 th = GNUNET_malloc (sizeof (struct GNUNET_TRANSPORT_TransmitHandle));
842 th->notify_cls = notify_cls;
843 th->notify_size = size;
844 GNUNET_CONTAINER_DLL_insert_tail (h->control_head, h->control_tail, th);
845 schedule_transmission (h);
850 * Transmit START message to service.
853 * @param size number of bytes available in buf
854 * @param buf where to copy the message
855 * @return number of bytes copied to buf
858 send_start (void *cls, size_t size, void *buf)
860 struct GNUNET_TRANSPORT_Handle *h = cls;
861 struct StartMessage s;
865 /* Can only be shutdown, just give up */
866 #if DEBUG_TRANSPORT_API
867 LOG (GNUNET_ERROR_TYPE_DEBUG,
868 "Shutdown while trying to transmit `%s' request.\n", "START");
872 #if DEBUG_TRANSPORT_API
873 LOG (GNUNET_ERROR_TYPE_DEBUG, "Transmitting `%s' request.\n", "START");
875 GNUNET_assert (size >= sizeof (struct StartMessage));
876 s.header.size = htons (sizeof (struct StartMessage));
877 s.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_START);
878 s.do_check = htonl (h->check_self);
880 memcpy (buf, &s, sizeof (struct StartMessage));
881 GNUNET_CLIENT_receive (h->client, &demultiplexer, h,
882 GNUNET_TIME_UNIT_FOREVER_REL);
883 return sizeof (struct StartMessage);
888 * Try again to connect to transport service.
890 * @param cls the handle to the transport service
891 * @param tc scheduler context
894 reconnect (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
896 struct GNUNET_TRANSPORT_Handle *h = cls;
898 h->reconnect_task = GNUNET_SCHEDULER_NO_TASK;
899 if ((tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN) != 0)
901 /* shutdown, just give up */
904 #if DEBUG_TRANSPORT_API
905 LOG (GNUNET_ERROR_TYPE_DEBUG, "Connecting to transport service.\n");
907 GNUNET_assert (h->client == NULL);
908 GNUNET_assert (h->control_head == NULL);
909 GNUNET_assert (h->control_tail == NULL);
910 h->client = GNUNET_CLIENT_connect ("transport", h->cfg);
911 GNUNET_assert (h->client != NULL);
912 schedule_control_transmit (h, sizeof (struct StartMessage), &send_start, h);
917 * Function that will schedule the job that will try
918 * to connect us again to the client.
920 * @param h transport service to reconnect
923 disconnect_and_schedule_reconnect (struct GNUNET_TRANSPORT_Handle *h)
925 struct GNUNET_TRANSPORT_TransmitHandle *th;
927 GNUNET_assert (h->reconnect_task == GNUNET_SCHEDULER_NO_TASK);
928 /* Forget about all neighbours that we used to be connected to */
929 GNUNET_CONTAINER_multihashmap_iterate (h->neighbours, &neighbour_delete, h);
932 GNUNET_CLIENT_notify_transmit_ready_cancel (h->cth);
935 if (NULL != h->client)
937 GNUNET_CLIENT_disconnect (h->client, GNUNET_YES);
940 if (h->quota_task != GNUNET_SCHEDULER_NO_TASK)
942 GNUNET_SCHEDULER_cancel (h->quota_task);
943 h->quota_task = GNUNET_SCHEDULER_NO_TASK;
945 while ((NULL != (th = h->control_head)))
947 GNUNET_CONTAINER_DLL_remove (h->control_head, h->control_tail, th);
948 th->notify (th->notify_cls, 0, NULL);
951 #if DEBUG_TRANSPORT_API
952 LOG (GNUNET_ERROR_TYPE_DEBUG,
953 "Scheduling task to reconnect to transport service in %llu ms.\n",
954 h->reconnect_delay.rel_value);
957 GNUNET_SCHEDULER_add_delayed (h->reconnect_delay, &reconnect, h);
958 if (h->reconnect_delay.rel_value == 0)
960 h->reconnect_delay = GNUNET_TIME_UNIT_MILLISECONDS;
964 h->reconnect_delay = GNUNET_TIME_relative_multiply (h->reconnect_delay, 2);
966 GNUNET_TIME_relative_min (GNUNET_TIME_UNIT_SECONDS, h->reconnect_delay);
972 * Send REQUEST_CONNECT message to the service.
974 * @param cls the 'struct GNUNET_PeerIdentity'
975 * @param size number of bytes available in buf
976 * @param buf where to copy the message
977 * @return number of bytes copied to buf
980 send_try_connect (void *cls, size_t size, void *buf)
982 struct GNUNET_PeerIdentity *pid = cls;
983 struct TransportRequestConnectMessage msg;
990 #if DEBUG_TRANSPORT_API
991 LOG (GNUNET_ERROR_TYPE_DEBUG,
992 "Transmitting `%s' request with respect to `%4s'.\n", "REQUEST_CONNECT",
995 GNUNET_assert (size >= sizeof (struct TransportRequestConnectMessage));
996 msg.header.size = htons (sizeof (struct TransportRequestConnectMessage));
997 msg.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_REQUEST_CONNECT);
998 msg.reserved = htonl (0);
1000 memcpy (buf, &msg, sizeof (msg));
1002 return sizeof (struct TransportRequestConnectMessage);
1007 * Ask the transport service to establish a connection to
1010 * @param handle connection to transport service
1011 * @param target who we should try to connect to
1014 GNUNET_TRANSPORT_try_connect (struct GNUNET_TRANSPORT_Handle *handle,
1015 const struct GNUNET_PeerIdentity *target)
1017 struct GNUNET_PeerIdentity *pid;
1019 if (NULL == handle->client)
1021 pid = GNUNET_malloc (sizeof (struct GNUNET_PeerIdentity));
1023 schedule_control_transmit (handle,
1024 sizeof (struct TransportRequestConnectMessage),
1025 &send_try_connect, pid);
1030 * Send HELLO message to the service.
1032 * @param cls the HELLO message to send
1033 * @param size number of bytes available in buf
1034 * @param buf where to copy the message
1035 * @return number of bytes copied to buf
1038 send_hello (void *cls, size_t size, void *buf)
1040 struct GNUNET_MessageHeader *msg = cls;
1045 #if DEBUG_TRANSPORT_TIMEOUT
1046 LOG (GNUNET_ERROR_TYPE_DEBUG,
1047 "Timeout while trying to transmit `%s' request.\n", "HELLO");
1052 #if DEBUG_TRANSPORT_API
1053 LOG (GNUNET_ERROR_TYPE_DEBUG, "Transmitting `%s' request.\n", "HELLO");
1055 ssize = ntohs (msg->size);
1056 GNUNET_assert (size >= ssize);
1057 memcpy (buf, msg, ssize);
1064 * Offer the transport service the HELLO of another peer. Note that
1065 * the transport service may just ignore this message if the HELLO is
1066 * malformed or useless due to our local configuration.
1068 * @param handle connection to transport service
1069 * @param hello the hello message
1070 * @param cont continuation to call when HELLO has been sent
1071 * @param cls closure for continuation
1075 GNUNET_TRANSPORT_offer_hello (struct GNUNET_TRANSPORT_Handle *handle,
1076 const struct GNUNET_MessageHeader *hello,
1077 GNUNET_SCHEDULER_Task cont, void *cls)
1080 struct GNUNET_PeerIdentity peer;
1081 struct GNUNET_MessageHeader *msg;
1083 if (NULL == handle->client)
1085 GNUNET_break (ntohs (hello->type) == GNUNET_MESSAGE_TYPE_HELLO);
1086 size = ntohs (hello->size);
1087 GNUNET_break (size >= sizeof (struct GNUNET_MessageHeader));
1089 GNUNET_HELLO_get_id ((const struct GNUNET_HELLO_Message *) hello, &peer))
1094 msg = GNUNET_malloc (size);
1095 memcpy (msg, hello, size);
1096 #if DEBUG_TRANSPORT_API
1097 LOG (GNUNET_ERROR_TYPE_DEBUG,
1098 "Offering `%s' message of `%4s' to transport for validation.\n", "HELLO",
1099 GNUNET_i2s (&peer));
1101 schedule_control_transmit (handle, size, &send_hello, msg);
1106 * Obtain the HELLO message for this peer.
1108 * @param handle connection to transport service
1109 * @param rec function to call with the HELLO, sender will be our peer
1110 * identity; message and sender will be NULL on timeout
1111 * (handshake with transport service pending/failed).
1112 * cost estimate will be 0.
1113 * @param rec_cls closure for rec
1114 * @return handle to cancel the operation
1116 struct GNUNET_TRANSPORT_GetHelloHandle *
1117 GNUNET_TRANSPORT_get_hello (struct GNUNET_TRANSPORT_Handle *handle,
1118 GNUNET_TRANSPORT_HelloUpdateCallback rec,
1121 struct GNUNET_TRANSPORT_GetHelloHandle *hwl;
1123 hwl = GNUNET_malloc (sizeof (struct GNUNET_TRANSPORT_GetHelloHandle));
1125 hwl->rec_cls = rec_cls;
1126 hwl->handle = handle;
1127 GNUNET_CONTAINER_DLL_insert (handle->hwl_head, handle->hwl_tail, hwl);
1128 if (handle->my_hello != NULL)
1129 rec (rec_cls, (const struct GNUNET_MessageHeader *) handle->my_hello);
1135 * Stop receiving updates about changes to our HELLO message.
1137 * @param ghh handle to cancel
1140 GNUNET_TRANSPORT_get_hello_cancel (struct GNUNET_TRANSPORT_GetHelloHandle *ghh)
1142 struct GNUNET_TRANSPORT_Handle *handle = ghh->handle;
1144 GNUNET_CONTAINER_DLL_remove (handle->hwl_head, handle->hwl_tail, ghh);
1150 * Connect to the transport service. Note that the connection may
1151 * complete (or fail) asynchronously.
1153 * @param cfg configuration to use
1154 * @param self our own identity (API should check that it matches
1155 * the identity found by transport), or NULL (no check)
1156 * @param cls closure for the callbacks
1157 * @param rec receive function to call
1158 * @param nc function to call on connect events
1159 * @param nd function to call on disconnect events
1161 struct GNUNET_TRANSPORT_Handle *
1162 GNUNET_TRANSPORT_connect (const struct GNUNET_CONFIGURATION_Handle *cfg,
1163 const struct GNUNET_PeerIdentity *self, void *cls,
1164 GNUNET_TRANSPORT_ReceiveCallback rec,
1165 GNUNET_TRANSPORT_NotifyConnect nc,
1166 GNUNET_TRANSPORT_NotifyDisconnect nd)
1168 struct GNUNET_TRANSPORT_Handle *ret;
1170 ret = GNUNET_malloc (sizeof (struct GNUNET_TRANSPORT_Handle));
1174 ret->check_self = GNUNET_YES;
1181 ret->reconnect_delay = GNUNET_TIME_UNIT_ZERO;
1183 GNUNET_CONTAINER_multihashmap_create (STARTING_NEIGHBOURS_SIZE);
1185 GNUNET_CONTAINER_heap_create (GNUNET_CONTAINER_HEAP_ORDER_MIN);
1186 ret->reconnect_task = GNUNET_SCHEDULER_add_now (&reconnect, ret);
1192 * Disconnect from the transport service.
1194 * @param handle handle to the service as returned from GNUNET_TRANSPORT_connect
1197 GNUNET_TRANSPORT_disconnect (struct GNUNET_TRANSPORT_Handle *handle)
1199 #if DEBUG_TRANSPORT_API
1200 LOG (GNUNET_ERROR_TYPE_DEBUG, "Transport disconnect called!\n");
1202 /* this disconnects all neighbours... */
1203 if (handle->reconnect_task == GNUNET_SCHEDULER_NO_TASK)
1204 disconnect_and_schedule_reconnect (handle);
1205 /* and now we stop trying to connect again... */
1206 if (handle->reconnect_task != GNUNET_SCHEDULER_NO_TASK)
1208 GNUNET_SCHEDULER_cancel (handle->reconnect_task);
1209 handle->reconnect_task = GNUNET_SCHEDULER_NO_TASK;
1211 GNUNET_CONTAINER_multihashmap_destroy (handle->neighbours);
1212 handle->neighbours = NULL;
1213 if (handle->quota_task != GNUNET_SCHEDULER_NO_TASK)
1215 GNUNET_SCHEDULER_cancel (handle->quota_task);
1216 handle->quota_task = GNUNET_SCHEDULER_NO_TASK;
1218 GNUNET_free_non_null (handle->my_hello);
1219 handle->my_hello = NULL;
1220 GNUNET_assert (handle->hwl_head == NULL);
1221 GNUNET_assert (handle->hwl_tail == NULL);
1222 GNUNET_CONTAINER_heap_destroy (handle->ready_heap);
1223 handle->ready_heap = NULL;
1224 GNUNET_free (handle);
1229 * Check if we could queue a message of the given size for
1230 * transmission. The transport service will take both its
1231 * internal buffers and bandwidth limits imposed by the
1232 * other peer into consideration when answering this query.
1234 * @param handle connection to transport service
1235 * @param target who should receive the message
1236 * @param size how big is the message we want to transmit?
1237 * @param priority how important is the message?
1238 * @param timeout after how long should we give up (and call
1239 * notify with buf NULL and size 0)?
1240 * @param notify function to call when we are ready to
1241 * send such a message
1242 * @param notify_cls closure for notify
1243 * @return NULL if someone else is already waiting to be notified
1244 * non-NULL if the notify callback was queued (can be used to cancel
1245 * using GNUNET_TRANSPORT_notify_transmit_ready_cancel)
1247 struct GNUNET_TRANSPORT_TransmitHandle *
1248 GNUNET_TRANSPORT_notify_transmit_ready (struct GNUNET_TRANSPORT_Handle *handle,
1249 const struct GNUNET_PeerIdentity
1250 *target, size_t size, uint32_t priority,
1251 struct GNUNET_TIME_Relative timeout,
1252 GNUNET_CONNECTION_TransmitReadyNotify
1253 notify, void *notify_cls)
1255 struct Neighbour *n;
1256 struct GNUNET_TRANSPORT_TransmitHandle *th;
1257 struct GNUNET_TIME_Relative delay;
1259 n = neighbour_find (handle, target);
1262 /* use GNUNET_TRANSPORT_try_connect first, only use this function
1263 * once a connection has been established */
1269 /* attempt to send two messages at the same time to the same peer */
1273 GNUNET_assert (NULL == n->hn);
1274 th = GNUNET_malloc (sizeof (struct GNUNET_TRANSPORT_TransmitHandle));
1276 th->notify = notify;
1277 th->notify_cls = notify_cls;
1278 th->timeout = GNUNET_TIME_relative_to_absolute (timeout);
1279 th->notify_size = size;
1280 th->priority = priority;
1282 /* calculate when our transmission should be ready */
1283 delay = GNUNET_BANDWIDTH_tracker_get_delay (&n->out_tracker, size);
1284 if (delay.rel_value > timeout.rel_value)
1285 delay.rel_value = 0; /* notify immediately (with failure) */
1286 #if DEBUG_TRANSPORT_API
1287 LOG (GNUNET_ERROR_TYPE_DEBUG,
1288 "Bandwidth tracker allows next transmission to peer %s in %llu ms\n",
1289 GNUNET_i2s (target), (unsigned long long) delay.rel_value);
1291 n->hn = GNUNET_CONTAINER_heap_insert (handle->ready_heap, n, delay.rel_value);
1292 schedule_transmission (handle);
1298 * Cancel the specified transmission-ready notification.
1300 * @param th handle returned from GNUNET_TRANSPORT_notify_transmit_ready
1303 GNUNET_TRANSPORT_notify_transmit_ready_cancel (struct
1304 GNUNET_TRANSPORT_TransmitHandle
1307 struct Neighbour *n;
1309 GNUNET_assert (NULL == th->next);
1310 GNUNET_assert (NULL == th->prev);
1312 GNUNET_assert (th == n->th);
1316 GNUNET_CONTAINER_heap_remove_node (n->hn);
1321 GNUNET_assert (GNUNET_SCHEDULER_NO_TASK != th->timeout_task);
1322 GNUNET_SCHEDULER_cancel (th->timeout_task);
1323 th->timeout_task = GNUNET_SCHEDULER_NO_TASK;
1329 /* end of transport_api.c */