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
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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.
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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 const struct GNUNET_ATS_Information *ats;
409 struct GNUNET_TRANSPORT_GetHelloHandle *hwl;
410 struct GNUNET_TRANSPORT_GetHelloHandle *next_hwl;
412 struct GNUNET_PeerIdentity me;
416 GNUNET_assert (h->client != NULL);
419 #if DEBUG_TRANSPORT_API
420 LOG (GNUNET_ERROR_TYPE_INFO,
421 "Error receiving from transport service, disconnecting temporarily.\n");
423 disconnect_and_schedule_reconnect (h);
426 GNUNET_CLIENT_receive (h->client, &demultiplexer, h,
427 GNUNET_TIME_UNIT_FOREVER_REL);
428 size = ntohs (msg->size);
429 switch (ntohs (msg->type))
431 case GNUNET_MESSAGE_TYPE_HELLO:
433 GNUNET_HELLO_get_id ((const struct GNUNET_HELLO_Message *) msg, &me))
438 #if DEBUG_TRANSPORT_API
439 LOG (GNUNET_ERROR_TYPE_DEBUG,
440 "Receiving (my own) `%s' message, I am `%4s'.\n", "HELLO",
443 GNUNET_free_non_null (h->my_hello);
445 if (size < sizeof (struct GNUNET_MessageHeader))
450 h->my_hello = GNUNET_malloc (size);
451 memcpy (h->my_hello, msg, size);
455 next_hwl = hwl->next;
456 hwl->rec (hwl->rec_cls,
457 (const struct GNUNET_MessageHeader *) h->my_hello);
461 case GNUNET_MESSAGE_TYPE_TRANSPORT_CONNECT:
462 if (size < sizeof (struct ConnectInfoMessage))
467 cim = (const struct ConnectInfoMessage *) msg;
468 ats_count = ntohl (cim->ats_count);
470 sizeof (struct ConnectInfoMessage) +
471 ats_count * sizeof (struct GNUNET_ATS_Information))
476 ats = (const struct GNUNET_ATS_Information *) &cim[1];
477 #if DEBUG_TRANSPORT_API
478 LOG (GNUNET_ERROR_TYPE_DEBUG, "Receiving `%s' message for `%4s'.\n",
479 "CONNECT", GNUNET_i2s (&cim->id));
481 n = neighbour_find (h, &cim->id);
487 n = neighbour_add (h, &cim->id);
488 if (h->nc_cb != NULL)
489 h->nc_cb (h->cls, &n->id, ats, ats_count);
491 case GNUNET_MESSAGE_TYPE_TRANSPORT_DISCONNECT:
492 if (size != sizeof (struct DisconnectInfoMessage))
497 dim = (const struct DisconnectInfoMessage *) msg;
498 GNUNET_break (ntohl (dim->reserved) == 0);
499 #if DEBUG_TRANSPORT_API_DISCONNECT
500 LOG (GNUNET_ERROR_TYPE_DEBUG, "Receiving `%s' message for `%4s'.\n",
501 "DISCONNECT", GNUNET_i2s (&dim->peer));
503 n = neighbour_find (h, &dim->peer);
509 neighbour_delete (h, &dim->peer.hashPubKey, n);
511 case GNUNET_MESSAGE_TYPE_TRANSPORT_SEND_OK:
512 if (size != sizeof (struct SendOkMessage))
517 okm = (const struct SendOkMessage *) msg;
518 #if DEBUG_TRANSPORT_API
519 LOG (GNUNET_ERROR_TYPE_DEBUG, "Receiving `%s' message, transmission %s.\n",
520 "SEND_OK", ntohl (okm->success) == GNUNET_OK ? "succeeded" : "failed");
522 n = neighbour_find (h, &okm->peer);
525 GNUNET_break (GNUNET_NO == n->is_ready);
526 n->is_ready = GNUNET_YES;
527 if ((n->th != NULL) && (n->hn == NULL))
529 GNUNET_assert (GNUNET_SCHEDULER_NO_TASK != n->th->timeout_task);
530 GNUNET_SCHEDULER_cancel (n->th->timeout_task);
531 n->th->timeout_task = GNUNET_SCHEDULER_NO_TASK;
532 /* we've been waiting for this (congestion, not quota,
533 * caused delayed transmission) */
534 n->hn = GNUNET_CONTAINER_heap_insert (h->ready_heap, n, 0);
535 schedule_transmission (h);
538 case GNUNET_MESSAGE_TYPE_TRANSPORT_RECV:
539 #if DEBUG_TRANSPORT_API
540 LOG (GNUNET_ERROR_TYPE_DEBUG, "Receiving `%s' message.\n", "RECV");
543 sizeof (struct InboundMessage) + sizeof (struct GNUNET_MessageHeader))
548 im = (const struct InboundMessage *) msg;
549 ats_count = ntohl (im->ats_count);
550 ats = (const struct GNUNET_ATS_Information *) &im[1];
551 imm = (const struct GNUNET_MessageHeader *) &ats[ats_count];
552 if (ntohs (imm->size) + sizeof (struct InboundMessage) +
553 ats_count * sizeof (struct GNUNET_ATS_Information) != size)
558 #if DEBUG_TRANSPORT_API
559 LOG (GNUNET_ERROR_TYPE_DEBUG, "Received message of type %u from `%4s'.\n",
560 ntohs (imm->type), GNUNET_i2s (&im->peer));
562 n = neighbour_find (h, &im->peer);
569 h->rec (h->cls, &im->peer, imm, ats, ats_count);
571 case GNUNET_MESSAGE_TYPE_TRANSPORT_SET_QUOTA:
572 #if DEBUG_TRANSPORT_API
573 LOG (GNUNET_ERROR_TYPE_DEBUG, "Receiving `%s' message.\n", "SET_QUOTA");
575 if (size != sizeof (struct QuotaSetMessage))
580 qm = (const struct QuotaSetMessage *) msg;
581 n = neighbour_find (h, &qm->peer);
584 GNUNET_BANDWIDTH_tracker_update_quota (&n->out_tracker, qm->quota);
587 LOG (GNUNET_ERROR_TYPE_ERROR,
588 _("Received unexpected message of type %u in %s:%u\n"),
589 ntohs (msg->type), __FILE__, __LINE__);
597 * A transmission request could not be satisfied because of
598 * network congestion. Notify the initiator and clean up.
600 * @param cls the 'struct GNUNET_TRANSPORT_TransmitHandle'
601 * @param tc scheduler context
604 timeout_request_due_to_congestion (void *cls,
605 const struct GNUNET_SCHEDULER_TaskContext
608 struct GNUNET_TRANSPORT_TransmitHandle *th = cls;
609 struct Neighbour *n = th->neighbour;
611 n->th->timeout_task = GNUNET_SCHEDULER_NO_TASK;
612 GNUNET_assert (th == n->th);
613 GNUNET_assert (NULL == n->hn);
615 th->notify (th->notify_cls, 0, NULL);
621 * Transmit message(s) to service.
623 * @param cls handle to transport
624 * @param size number of bytes available in buf
625 * @param buf where to copy the message
626 * @return number of bytes copied to buf
629 transport_notify_ready (void *cls, size_t size, void *buf)
631 struct GNUNET_TRANSPORT_Handle *h = cls;
632 struct GNUNET_TRANSPORT_TransmitHandle *th;
635 struct OutboundMessage obm;
640 GNUNET_assert (NULL != h->client);
644 /* transmission failed */
645 disconnect_and_schedule_reconnect (h);
651 /* first send control messages */
652 while ((NULL != (th = h->control_head)) && (th->notify_size <= size))
654 GNUNET_CONTAINER_DLL_remove (h->control_head, h->control_tail, th);
655 nret = th->notify (th->notify_cls, size, &cbuf[ret]);
656 #if DEBUG_TRANSPORT_API
657 LOG (GNUNET_ERROR_TYPE_DEBUG, "Added %u bytes of control message at %u\n",
665 /* then, if possible and no control messages pending, send data messages */
666 while ((NULL == h->control_head) &&
667 (NULL != (n = GNUNET_CONTAINER_heap_peek (h->ready_heap))))
669 if (GNUNET_YES != n->is_ready)
671 /* peer not ready, wait for notification! */
672 GNUNET_assert (n == GNUNET_CONTAINER_heap_remove_root (h->ready_heap));
674 GNUNET_assert (GNUNET_SCHEDULER_NO_TASK == n->th->timeout_task);
675 n->th->timeout_task =
676 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_absolute_get_remaining
678 &timeout_request_due_to_congestion,
683 if (th->notify_size + sizeof (struct OutboundMessage) > size)
684 break; /* does not fit */
685 if (GNUNET_BANDWIDTH_tracker_get_delay
686 (&n->out_tracker, th->notify_size).rel_value > 0)
687 break; /* too early */
688 GNUNET_assert (n == GNUNET_CONTAINER_heap_remove_root (h->ready_heap));
691 n->is_ready = GNUNET_NO;
692 GNUNET_assert (size >= sizeof (struct OutboundMessage));
694 th->notify (th->notify_cls, size - sizeof (struct OutboundMessage),
695 &cbuf[ret + sizeof (struct OutboundMessage)]);
696 GNUNET_assert (mret <= size - sizeof (struct OutboundMessage));
699 GNUNET_assert (mret + sizeof (struct OutboundMessage) <
700 GNUNET_SERVER_MAX_MESSAGE_SIZE);
701 obm.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SEND);
702 obm.header.size = htons (mret + sizeof (struct OutboundMessage));
703 obm.priority = htonl (th->priority);
705 GNUNET_TIME_relative_hton (GNUNET_TIME_absolute_get_remaining
708 memcpy (&cbuf[ret], &obm, sizeof (struct OutboundMessage));
709 ret += (mret + sizeof (struct OutboundMessage));
710 size -= (mret + sizeof (struct OutboundMessage));
711 GNUNET_BANDWIDTH_tracker_consume (&n->out_tracker, mret);
715 /* if there are more pending messages, try to schedule those */
716 schedule_transmission (h);
717 #if DEBUG_TRANSPORT_API
718 LOG (GNUNET_ERROR_TYPE_DEBUG, "Transmitting %u bytes to transport service\n",
726 * Schedule the task to send one message, either from the control
727 * list or the peer message queues to the service.
729 * @param cls transport service to schedule a transmission for
730 * @param tc scheduler context
733 schedule_transmission_task (void *cls,
734 const struct GNUNET_SCHEDULER_TaskContext *tc)
736 struct GNUNET_TRANSPORT_Handle *h = cls;
738 struct GNUNET_TRANSPORT_TransmitHandle *th;
741 h->quota_task = GNUNET_SCHEDULER_NO_TASK;
742 GNUNET_assert (NULL != h->client);
743 /* destroy all requests that have timed out */
744 while ((NULL != (n = GNUNET_CONTAINER_heap_peek (h->ready_heap))) &&
745 (GNUNET_TIME_absolute_get_remaining (n->th->timeout).rel_value == 0))
747 /* notify client that the request could not be satisfied within
748 * the given time constraints */
751 GNUNET_assert (n == GNUNET_CONTAINER_heap_remove_root (h->ready_heap));
753 #if DEBUG_TRANSPORT_API
754 LOG (GNUNET_ERROR_TYPE_DEBUG,
755 "Signalling timeout for transmission to peer %s due to congestion\n",
756 GNUNET_i2s (&n->id));
758 GNUNET_assert (0 == th->notify (th->notify_cls, 0, NULL));
763 if (NULL != h->control_head)
765 size = h->control_head->notify_size;
769 n = GNUNET_CONTAINER_heap_peek (h->ready_heap);
771 return; /* no pending messages */
772 size = n->th->notify_size + sizeof (struct OutboundMessage);
774 #if DEBUG_TRANSPORT_API
775 LOG (GNUNET_ERROR_TYPE_DEBUG, "Calling notify_transmit_ready\n");
778 GNUNET_CLIENT_notify_transmit_ready (h->client, size,
779 GNUNET_TIME_UNIT_FOREVER_REL,
780 GNUNET_NO, &transport_notify_ready,
782 GNUNET_assert (NULL != h->cth);
787 * Schedule the task to send one message, either from the control
788 * list or the peer message queues to the service.
790 * @param h transport service to schedule a transmission for
793 schedule_transmission (struct GNUNET_TRANSPORT_Handle *h)
795 struct GNUNET_TIME_Relative delay;
798 GNUNET_assert (NULL != h->client);
799 if (h->quota_task != GNUNET_SCHEDULER_NO_TASK)
801 GNUNET_SCHEDULER_cancel (h->quota_task);
802 h->quota_task = GNUNET_SCHEDULER_NO_TASK;
804 if (NULL != h->control_head)
805 delay = GNUNET_TIME_UNIT_ZERO;
806 else if (NULL != (n = GNUNET_CONTAINER_heap_peek (h->ready_heap)))
808 GNUNET_BANDWIDTH_tracker_get_delay (&n->out_tracker,
811 return; /* no work to be done */
812 #if DEBUG_TRANSPORT_API
813 LOG (GNUNET_ERROR_TYPE_DEBUG,
814 "Scheduling next transmission to service in %llu ms\n",
815 (unsigned long long) delay.rel_value);
818 GNUNET_SCHEDULER_add_delayed (delay, &schedule_transmission_task, h);
823 * Queue control request for transmission to the transport
826 * @param h handle to the transport service
827 * @param size number of bytes to be transmitted
828 * @param notify function to call to get the content
829 * @param notify_cls closure for notify
832 schedule_control_transmit (struct GNUNET_TRANSPORT_Handle *h, size_t size,
833 GNUNET_CONNECTION_TransmitReadyNotify notify,
836 struct GNUNET_TRANSPORT_TransmitHandle *th;
838 #if DEBUG_TRANSPORT_API
839 LOG (GNUNET_ERROR_TYPE_DEBUG, "Control transmit of %u bytes requested\n",
842 th = GNUNET_malloc (sizeof (struct GNUNET_TRANSPORT_TransmitHandle));
844 th->notify_cls = notify_cls;
845 th->notify_size = size;
846 GNUNET_CONTAINER_DLL_insert_tail (h->control_head, h->control_tail, th);
847 schedule_transmission (h);
852 * Transmit START message to service.
855 * @param size number of bytes available in buf
856 * @param buf where to copy the message
857 * @return number of bytes copied to buf
860 send_start (void *cls, size_t size, void *buf)
862 struct GNUNET_TRANSPORT_Handle *h = cls;
863 struct StartMessage s;
868 /* Can only be shutdown, just give up */
869 #if DEBUG_TRANSPORT_API
870 LOG (GNUNET_ERROR_TYPE_DEBUG,
871 "Shutdown while trying to transmit `%s' request.\n", "START");
875 #if DEBUG_TRANSPORT_API
876 LOG (GNUNET_ERROR_TYPE_DEBUG, "Transmitting `%s' request.\n", "START");
878 GNUNET_assert (size >= sizeof (struct StartMessage));
879 s.header.size = htons (sizeof (struct StartMessage));
880 s.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_START);
886 s.options = htonl (options);
888 memcpy (buf, &s, sizeof (struct StartMessage));
889 GNUNET_CLIENT_receive (h->client, &demultiplexer, h,
890 GNUNET_TIME_UNIT_FOREVER_REL);
891 return sizeof (struct StartMessage);
896 * Try again to connect to transport service.
898 * @param cls the handle to the transport service
899 * @param tc scheduler context
902 reconnect (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
904 struct GNUNET_TRANSPORT_Handle *h = cls;
906 h->reconnect_task = GNUNET_SCHEDULER_NO_TASK;
907 if ((tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN) != 0)
909 /* shutdown, just give up */
912 #if DEBUG_TRANSPORT_API
913 LOG (GNUNET_ERROR_TYPE_DEBUG, "Connecting to transport service.\n");
915 GNUNET_assert (h->client == NULL);
916 GNUNET_assert (h->control_head == NULL);
917 GNUNET_assert (h->control_tail == NULL);
918 h->client = GNUNET_CLIENT_connect ("transport", h->cfg);
919 GNUNET_assert (h->client != NULL);
920 schedule_control_transmit (h, sizeof (struct StartMessage), &send_start, h);
925 * Function that will schedule the job that will try
926 * to connect us again to the client.
928 * @param h transport service to reconnect
931 disconnect_and_schedule_reconnect (struct GNUNET_TRANSPORT_Handle *h)
933 struct GNUNET_TRANSPORT_TransmitHandle *th;
935 GNUNET_assert (h->reconnect_task == GNUNET_SCHEDULER_NO_TASK);
938 GNUNET_CLIENT_notify_transmit_ready_cancel (h->cth);
941 if (NULL != h->client)
943 GNUNET_CLIENT_disconnect (h->client);
946 /* Forget about all neighbours that we used to be connected to */
947 GNUNET_CONTAINER_multihashmap_iterate (h->neighbours, &neighbour_delete, h);
948 if (h->quota_task != GNUNET_SCHEDULER_NO_TASK)
950 GNUNET_SCHEDULER_cancel (h->quota_task);
951 h->quota_task = GNUNET_SCHEDULER_NO_TASK;
953 while ((NULL != (th = h->control_head)))
955 GNUNET_CONTAINER_DLL_remove (h->control_head, h->control_tail, th);
956 th->notify (th->notify_cls, 0, NULL);
959 #if DEBUG_TRANSPORT_API
960 LOG (GNUNET_ERROR_TYPE_DEBUG,
961 "Scheduling task to reconnect to transport service in %llu ms.\n",
962 h->reconnect_delay.rel_value);
965 GNUNET_SCHEDULER_add_delayed (h->reconnect_delay, &reconnect, h);
966 if (h->reconnect_delay.rel_value == 0)
968 h->reconnect_delay = GNUNET_TIME_UNIT_MILLISECONDS;
972 h->reconnect_delay = GNUNET_TIME_relative_multiply (h->reconnect_delay, 2);
974 GNUNET_TIME_relative_min (GNUNET_TIME_UNIT_SECONDS, h->reconnect_delay);
980 * Send REQUEST_CONNECT message to the service.
982 * @param cls the 'struct GNUNET_PeerIdentity'
983 * @param size number of bytes available in buf
984 * @param buf where to copy the message
985 * @return number of bytes copied to buf
988 send_try_connect (void *cls, size_t size, void *buf)
990 struct GNUNET_PeerIdentity *pid = cls;
991 struct TransportRequestConnectMessage msg;
998 #if DEBUG_TRANSPORT_API
999 LOG (GNUNET_ERROR_TYPE_DEBUG,
1000 "Transmitting `%s' request with respect to `%4s'.\n", "REQUEST_CONNECT",
1003 GNUNET_assert (size >= sizeof (struct TransportRequestConnectMessage));
1004 msg.header.size = htons (sizeof (struct TransportRequestConnectMessage));
1005 msg.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_REQUEST_CONNECT);
1006 msg.reserved = htonl (0);
1008 memcpy (buf, &msg, sizeof (msg));
1010 return sizeof (struct TransportRequestConnectMessage);
1015 * Ask the transport service to establish a connection to
1018 * @param handle connection to transport service
1019 * @param target who we should try to connect to
1022 GNUNET_TRANSPORT_try_connect (struct GNUNET_TRANSPORT_Handle *handle,
1023 const struct GNUNET_PeerIdentity *target)
1025 struct GNUNET_PeerIdentity *pid;
1027 if (NULL == handle->client)
1029 pid = GNUNET_malloc (sizeof (struct GNUNET_PeerIdentity));
1031 schedule_control_transmit (handle,
1032 sizeof (struct TransportRequestConnectMessage),
1033 &send_try_connect, pid);
1038 * Send HELLO message to the service.
1040 * @param cls the HELLO message to send
1041 * @param size number of bytes available in buf
1042 * @param buf where to copy the message
1043 * @return number of bytes copied to buf
1046 send_hello (void *cls, size_t size, void *buf)
1048 struct GNUNET_MessageHeader *msg = cls;
1053 #if DEBUG_TRANSPORT_TIMEOUT
1054 LOG (GNUNET_ERROR_TYPE_DEBUG,
1055 "Timeout while trying to transmit `%s' request.\n", "HELLO");
1060 #if DEBUG_TRANSPORT_API
1061 LOG (GNUNET_ERROR_TYPE_DEBUG, "Transmitting `%s' request.\n", "HELLO");
1063 ssize = ntohs (msg->size);
1064 GNUNET_assert (size >= ssize);
1065 memcpy (buf, msg, ssize);
1072 * Offer the transport service the HELLO of another peer. Note that
1073 * the transport service may just ignore this message if the HELLO is
1074 * malformed or useless due to our local configuration.
1076 * @param handle connection to transport service
1077 * @param hello the hello message
1078 * @param cont continuation to call when HELLO has been sent
1079 * @param cls closure for continuation
1083 GNUNET_TRANSPORT_offer_hello (struct GNUNET_TRANSPORT_Handle *handle,
1084 const struct GNUNET_MessageHeader *hello,
1085 GNUNET_SCHEDULER_Task cont, void *cls)
1088 struct GNUNET_PeerIdentity peer;
1089 struct GNUNET_MessageHeader *msg;
1091 if (NULL == handle->client)
1093 GNUNET_break (ntohs (hello->type) == GNUNET_MESSAGE_TYPE_HELLO);
1094 size = ntohs (hello->size);
1095 GNUNET_break (size >= sizeof (struct GNUNET_MessageHeader));
1097 GNUNET_HELLO_get_id ((const struct GNUNET_HELLO_Message *) hello, &peer))
1102 msg = GNUNET_malloc (size);
1103 memcpy (msg, hello, size);
1104 #if DEBUG_TRANSPORT_API
1105 LOG (GNUNET_ERROR_TYPE_DEBUG,
1106 "Offering `%s' message of `%4s' to transport for validation.\n", "HELLO",
1107 GNUNET_i2s (&peer));
1109 schedule_control_transmit (handle, size, &send_hello, msg);
1114 * Obtain the HELLO message for this peer.
1116 * @param handle connection to transport service
1117 * @param rec function to call with the HELLO, sender will be our peer
1118 * identity; message and sender will be NULL on timeout
1119 * (handshake with transport service pending/failed).
1120 * cost estimate will be 0.
1121 * @param rec_cls closure for rec
1122 * @return handle to cancel the operation
1124 struct GNUNET_TRANSPORT_GetHelloHandle *
1125 GNUNET_TRANSPORT_get_hello (struct GNUNET_TRANSPORT_Handle *handle,
1126 GNUNET_TRANSPORT_HelloUpdateCallback rec,
1129 struct GNUNET_TRANSPORT_GetHelloHandle *hwl;
1131 hwl = GNUNET_malloc (sizeof (struct GNUNET_TRANSPORT_GetHelloHandle));
1133 hwl->rec_cls = rec_cls;
1134 hwl->handle = handle;
1135 GNUNET_CONTAINER_DLL_insert (handle->hwl_head, handle->hwl_tail, hwl);
1136 if (handle->my_hello != NULL)
1137 rec (rec_cls, (const struct GNUNET_MessageHeader *) handle->my_hello);
1143 * Stop receiving updates about changes to our HELLO message.
1145 * @param ghh handle to cancel
1148 GNUNET_TRANSPORT_get_hello_cancel (struct GNUNET_TRANSPORT_GetHelloHandle *ghh)
1150 struct GNUNET_TRANSPORT_Handle *handle = ghh->handle;
1152 GNUNET_CONTAINER_DLL_remove (handle->hwl_head, handle->hwl_tail, ghh);
1158 * Connect to the transport service. Note that the connection may
1159 * complete (or fail) asynchronously.
1161 * @param cfg configuration to use
1162 * @param self our own identity (API should check that it matches
1163 * the identity found by transport), or NULL (no check)
1164 * @param cls closure for the callbacks
1165 * @param rec receive function to call
1166 * @param nc function to call on connect events
1167 * @param nd function to call on disconnect events
1169 struct GNUNET_TRANSPORT_Handle *
1170 GNUNET_TRANSPORT_connect (const struct GNUNET_CONFIGURATION_Handle *cfg,
1171 const struct GNUNET_PeerIdentity *self, void *cls,
1172 GNUNET_TRANSPORT_ReceiveCallback rec,
1173 GNUNET_TRANSPORT_NotifyConnect nc,
1174 GNUNET_TRANSPORT_NotifyDisconnect nd)
1176 struct GNUNET_TRANSPORT_Handle *ret;
1178 ret = GNUNET_malloc (sizeof (struct GNUNET_TRANSPORT_Handle));
1182 ret->check_self = GNUNET_YES;
1189 ret->reconnect_delay = GNUNET_TIME_UNIT_ZERO;
1191 GNUNET_CONTAINER_multihashmap_create (STARTING_NEIGHBOURS_SIZE);
1193 GNUNET_CONTAINER_heap_create (GNUNET_CONTAINER_HEAP_ORDER_MIN);
1194 ret->reconnect_task = GNUNET_SCHEDULER_add_now (&reconnect, ret);
1200 * Disconnect from the transport service.
1202 * @param handle handle to the service as returned from GNUNET_TRANSPORT_connect
1205 GNUNET_TRANSPORT_disconnect (struct GNUNET_TRANSPORT_Handle *handle)
1207 #if DEBUG_TRANSPORT_API
1208 LOG (GNUNET_ERROR_TYPE_DEBUG, "Transport disconnect called!\n");
1210 /* this disconnects all neighbours... */
1211 if (handle->reconnect_task == GNUNET_SCHEDULER_NO_TASK)
1212 disconnect_and_schedule_reconnect (handle);
1213 /* and now we stop trying to connect again... */
1214 if (handle->reconnect_task != GNUNET_SCHEDULER_NO_TASK)
1216 GNUNET_SCHEDULER_cancel (handle->reconnect_task);
1217 handle->reconnect_task = GNUNET_SCHEDULER_NO_TASK;
1219 GNUNET_CONTAINER_multihashmap_destroy (handle->neighbours);
1220 handle->neighbours = NULL;
1221 if (handle->quota_task != GNUNET_SCHEDULER_NO_TASK)
1223 GNUNET_SCHEDULER_cancel (handle->quota_task);
1224 handle->quota_task = GNUNET_SCHEDULER_NO_TASK;
1226 GNUNET_free_non_null (handle->my_hello);
1227 handle->my_hello = NULL;
1228 GNUNET_assert (handle->hwl_head == NULL);
1229 GNUNET_assert (handle->hwl_tail == NULL);
1230 GNUNET_CONTAINER_heap_destroy (handle->ready_heap);
1231 handle->ready_heap = NULL;
1232 GNUNET_free (handle);
1237 * Check if we could queue a message of the given size for
1238 * transmission. The transport service will take both its
1239 * internal buffers and bandwidth limits imposed by the
1240 * other peer into consideration when answering this query.
1242 * @param handle connection to transport service
1243 * @param target who should receive the message
1244 * @param size how big is the message we want to transmit?
1245 * @param priority how important is the message?
1246 * @param timeout after how long should we give up (and call
1247 * notify with buf NULL and size 0)?
1248 * @param notify function to call when we are ready to
1249 * send such a message
1250 * @param notify_cls closure for notify
1251 * @return NULL if someone else is already waiting to be notified
1252 * non-NULL if the notify callback was queued (can be used to cancel
1253 * using GNUNET_TRANSPORT_notify_transmit_ready_cancel)
1255 struct GNUNET_TRANSPORT_TransmitHandle *
1256 GNUNET_TRANSPORT_notify_transmit_ready (struct GNUNET_TRANSPORT_Handle *handle,
1257 const struct GNUNET_PeerIdentity
1258 *target, size_t size, uint32_t priority,
1259 struct GNUNET_TIME_Relative timeout,
1260 GNUNET_CONNECTION_TransmitReadyNotify
1261 notify, void *notify_cls)
1263 struct Neighbour *n;
1264 struct GNUNET_TRANSPORT_TransmitHandle *th;
1265 struct GNUNET_TIME_Relative delay;
1267 n = neighbour_find (handle, target);
1270 /* use GNUNET_TRANSPORT_try_connect first, only use this function
1271 * once a connection has been established */
1277 /* attempt to send two messages at the same time to the same peer */
1281 GNUNET_assert (NULL == n->hn);
1282 th = GNUNET_malloc (sizeof (struct GNUNET_TRANSPORT_TransmitHandle));
1284 th->notify = notify;
1285 th->notify_cls = notify_cls;
1286 th->timeout = GNUNET_TIME_relative_to_absolute (timeout);
1287 th->notify_size = size;
1288 th->priority = priority;
1290 /* calculate when our transmission should be ready */
1291 delay = GNUNET_BANDWIDTH_tracker_get_delay (&n->out_tracker, size);
1292 if (delay.rel_value > timeout.rel_value)
1293 delay.rel_value = 0; /* notify immediately (with failure) */
1294 #if DEBUG_TRANSPORT_API
1295 LOG (GNUNET_ERROR_TYPE_DEBUG,
1296 "Bandwidth tracker allows next transmission to peer %s in %llu ms\n",
1297 GNUNET_i2s (target), (unsigned long long) delay.rel_value);
1299 n->hn = GNUNET_CONTAINER_heap_insert (handle->ready_heap, n, delay.rel_value);
1300 schedule_transmission (handle);
1306 * Cancel the specified transmission-ready notification.
1308 * @param th handle returned from GNUNET_TRANSPORT_notify_transmit_ready
1311 GNUNET_TRANSPORT_notify_transmit_ready_cancel (struct
1312 GNUNET_TRANSPORT_TransmitHandle
1315 struct Neighbour *n;
1317 GNUNET_assert (NULL == th->next);
1318 GNUNET_assert (NULL == th->prev);
1320 GNUNET_assert (th == n->th);
1324 GNUNET_CONTAINER_heap_remove_node (n->hn);
1329 GNUNET_assert (GNUNET_SCHEDULER_NO_TASK != th->timeout_task);
1330 GNUNET_SCHEDULER_cancel (th->timeout_task);
1331 th->timeout_task = GNUNET_SCHEDULER_NO_TASK;
1337 /* end of transport_api.c */