2 This file is part of GNUnet.
3 (C) 2009 Christian Grothoff (and other contributing authors)
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6 it under the terms of the GNU General Public License as published
7 by the Free Software Foundation; either version 2, 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 core/core_api.c
23 * @brief core service; this is the main API for encrypted P2P
25 * @author Christian Grothoff
28 #include "gnunet_core_service.h"
33 * Context for the core service connection.
35 struct GNUNET_CORE_Handle
41 struct GNUNET_SCHEDULER_Handle *sched;
44 * Configuration we're using.
46 const struct GNUNET_CONFIGURATION_Handle *cfg;
49 * Closure for the various callbacks.
54 * Function to call once we've handshaked with the core service.
56 GNUNET_CORE_StartupCallback init;
59 * Function to call whenever we're notified about a peer connecting
60 * (pre-connects, no session key exchange yet).
62 GNUNET_CORE_ConnectEventHandler pre_connects;
65 * Function to call whenever we're notified about a peer connecting.
67 GNUNET_CORE_ConnectEventHandler connects;
70 * Function to call whenever we're notified about a peer disconnecting.
72 GNUNET_CORE_DisconnectEventHandler disconnects;
75 * Function to call whenever we receive an inbound message.
77 GNUNET_CORE_MessageCallback inbound_notify;
80 * Function to call whenever we receive an outbound message.
82 GNUNET_CORE_MessageCallback outbound_notify;
85 * Function handlers for messages of particular type.
87 const struct GNUNET_CORE_MessageHandler *handlers;
90 * Our connection to the service for notifications.
92 struct GNUNET_CLIENT_Connection *client_notifications;
95 * Handle for our current transmission request.
97 struct GNUNET_CLIENT_TransmitHandle *th;
100 * Head of doubly-linked list of pending requests.
102 struct GNUNET_CORE_TransmitHandle *pending_head;
105 * Tail of doubly-linked list of pending requests.
107 struct GNUNET_CORE_TransmitHandle *pending_tail;
110 * Currently submitted request (or NULL)
112 struct GNUNET_CORE_TransmitHandle *submitted;
115 * Currently submitted request based on solicitation (or NULL)
117 struct GNUNET_CORE_TransmitHandle *solicit_transmit_req;
120 * Buffer where we store a message for transmission in response
121 * to a traffic solicitation (or NULL).
123 char *solicit_buffer;
126 * How long to wait until we time out the connection attempt?
128 struct GNUNET_TIME_Absolute startup_timeout;
131 * ID of reconnect task (if any).
133 GNUNET_SCHEDULER_TaskIdentifier reconnect_task;
136 * Number of entries in the handlers array.
141 * For inbound notifications without a specific handler, do
142 * we expect to only receive headers?
144 int inbound_hdr_only;
147 * For outbound notifications without a specific handler, do
148 * we expect to only receive headers?
150 int outbound_hdr_only;
153 * Are we currently disconnected and hence unable to forward
161 * Handle for a transmission request.
163 struct GNUNET_CORE_TransmitHandle
167 * We keep active transmit handles in a doubly-linked list.
169 struct GNUNET_CORE_TransmitHandle *next;
172 * We keep active transmit handles in a doubly-linked list.
174 struct GNUNET_CORE_TransmitHandle *prev;
177 * Corresponding core handle.
179 struct GNUNET_CORE_Handle *ch;
182 * Function that will be called to get the actual request
183 * (once we are ready to transmit this request to the core).
184 * The function will be called with a NULL buffer to signal
187 GNUNET_CONNECTION_TransmitReadyNotify get_message;
190 * Closure for get_message.
192 void *get_message_cls;
195 * If this entry is for a transmission request, pointer
196 * to the notify callback; otherwise NULL.
198 GNUNET_CONNECTION_TransmitReadyNotify notify;
201 * Closure for notify.
206 * Peer the request is about.
208 struct GNUNET_PeerIdentity peer;
211 * Timeout for this handle.
213 struct GNUNET_TIME_Absolute timeout;
216 * ID of timeout task.
218 GNUNET_SCHEDULER_TaskIdentifier timeout_task;
221 * How important is this message?
226 * Size of this request.
235 reconnect_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc);
239 * Function called when we are ready to transmit our
240 * "START" message (or when this operation timed out).
243 * @param size number of bytes available in buf
244 * @param buf where the callee should write the message
245 * @return number of bytes written to buf
247 static size_t transmit_start (void *cls, size_t size, void *buf);
251 * Our current client connection went down. Clean it up
252 * and try to reconnect!
254 * @param h our handle to the core service
257 reconnect (struct GNUNET_CORE_Handle *h)
259 if (h->client_notifications != NULL)
260 GNUNET_CLIENT_disconnect (h->client_notifications, GNUNET_NO);
261 h->currently_down = GNUNET_YES;
262 h->client_notifications = GNUNET_CLIENT_connect (h->sched, "core", h->cfg);
263 if (h->client_notifications == NULL)
264 h->reconnect_task = GNUNET_SCHEDULER_add_delayed (h->sched,
265 GNUNET_TIME_UNIT_SECONDS,
269 h->th = GNUNET_CLIENT_notify_transmit_ready (h->client_notifications,
270 sizeof (struct InitMessage) +
271 sizeof (uint16_t) * h->hcnt,
272 GNUNET_TIME_UNIT_SECONDS,
279 * The given request hit its timeout. Remove from the
280 * doubly-linked list and call the respective continuation.
282 * @param cls the transmit handle of the request that timed out
283 * @param tc context, can be NULL (!)
286 timeout_request (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
288 struct GNUNET_CORE_TransmitHandle *th = cls;
290 th->timeout_task = GNUNET_SCHEDULER_NO_TASK;
291 GNUNET_assert (0 == th->get_message (th->get_message_cls, 0, NULL));
296 * Function called when we are ready to transmit a request from our
297 * request list (or when this operation timed out).
300 * @param size number of bytes available in buf
301 * @param buf where the callee should write the message
302 * @return number of bytes written to buf
305 request_start (void *cls, size_t size, void *buf)
307 struct GNUNET_CORE_Handle *h = cls;
308 struct GNUNET_CORE_TransmitHandle *th;
312 th = h->pending_head;
315 timeout_request (th, NULL);
318 /* create new timeout task (in case core takes too long to respond!) */
319 th->timeout_task = GNUNET_SCHEDULER_add_delayed (h->sched,
320 GNUNET_TIME_absolute_get_remaining
322 &timeout_request, th);
323 /* remove th from doubly-linked pending list, move to submitted */
324 GNUNET_assert (th->prev == NULL);
325 h->pending_head = th->next;
326 if (th->next == NULL)
327 h->pending_tail = NULL;
329 th->next->prev = NULL;
330 GNUNET_assert (h->submitted == NULL);
332 GNUNET_assert (size >= th->msize);
333 ret = th->get_message (th->get_message_cls, size, buf);
334 GNUNET_assert (ret <= size);
340 * Check the list of pending requests, send the next
344 trigger_next_request (struct GNUNET_CORE_Handle *h)
346 struct GNUNET_CORE_TransmitHandle *th;
348 if (h->currently_down)
351 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
352 "In trigger_next_request, connection currently down...\n");
354 return; /* connection temporarily down */
356 if (NULL == (th = h->pending_head))
357 return; /* no requests pending */
358 GNUNET_assert (NULL == h->th);
359 if (GNUNET_SCHEDULER_NO_TASK != th->timeout_task)
361 GNUNET_SCHEDULER_cancel (h->sched, th->timeout_task);
362 th->timeout_task = GNUNET_SCHEDULER_NO_TASK;
364 h->th = GNUNET_CLIENT_notify_transmit_ready (h->client_notifications,
366 GNUNET_TIME_absolute_get_remaining
375 * Handler for notification messages received from the core.
377 * @param cls our "struct GNUNET_CORE_Handle"
378 * @param msg the message received from the core service
381 main_notify_handler (void *cls, const struct GNUNET_MessageHeader *msg)
383 struct GNUNET_CORE_Handle *h = cls;
385 const struct ConnectNotifyMessage *cnm;
386 const struct DisconnectNotifyMessage *dnm;
387 const struct NotifyTrafficMessage *ntm;
388 const struct GNUNET_MessageHeader *em;
391 const struct GNUNET_CORE_MessageHandler *mh;
395 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
397 ("Client was disconnected from core service, trying to reconnect.\n"));
401 msize = ntohs (msg->size);
403 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
404 "Processing message of type %u and size %u from core service\n",
405 ntohs (msg->type), msize);
407 switch (ntohs (msg->type))
409 case GNUNET_MESSAGE_TYPE_CORE_NOTIFY_PRE_CONNECT:
410 if (NULL == h->pre_connects)
415 if (msize != sizeof (struct ConnectNotifyMessage))
420 cnm = (const struct ConnectNotifyMessage *) msg;
421 h->pre_connects (h->cls,
423 GNUNET_TIME_relative_ntoh (cnm->latency),
424 ntohl (cnm->distance));
426 case GNUNET_MESSAGE_TYPE_CORE_NOTIFY_CONNECT:
427 if (NULL == h->connects)
432 if (msize != sizeof (struct ConnectNotifyMessage))
437 cnm = (const struct ConnectNotifyMessage *) msg;
440 GNUNET_TIME_relative_ntoh (cnm->latency),
441 ntohl (cnm->distance));
443 case GNUNET_MESSAGE_TYPE_CORE_NOTIFY_DISCONNECT:
444 if (NULL == h->disconnects)
449 if (msize != sizeof (struct DisconnectNotifyMessage))
454 dnm = (const struct DisconnectNotifyMessage *) msg;
455 h->disconnects (h->cls,
458 case GNUNET_MESSAGE_TYPE_CORE_NOTIFY_INBOUND:
460 sizeof (struct NotifyTrafficMessage) +
461 sizeof (struct GNUNET_MessageHeader))
466 ntm = (const struct NotifyTrafficMessage *) msg;
467 em = (const struct GNUNET_MessageHeader *) &ntm[1];
469 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
470 "Received message of type %u from peer `%4s'\n",
471 ntohs (em->type), GNUNET_i2s (&ntm->peer));
473 if ((GNUNET_NO == h->inbound_hdr_only) &&
474 (msize != ntohs (em->size) + sizeof (struct NotifyTrafficMessage)))
479 et = ntohs (em->type);
480 for (hpos = 0; hpos < h->hcnt; hpos++)
482 mh = &h->handlers[hpos];
485 if ((mh->expected_size != ntohs (em->size)) &&
486 (mh->expected_size != 0))
492 h->handlers[hpos].callback (h->cls, &ntm->peer, em,
493 GNUNET_TIME_relative_ntoh (ntm->latency),
494 ntohl (ntm->distance)))
496 /* error in processing, disconnect ! */
501 if (NULL != h->inbound_notify)
502 h->inbound_notify (h->cls, &ntm->peer, em,
503 GNUNET_TIME_relative_ntoh (ntm->latency),
504 ntohl (ntm->distance));
506 case GNUNET_MESSAGE_TYPE_CORE_NOTIFY_OUTBOUND:
508 sizeof (struct NotifyTrafficMessage) +
509 sizeof (struct GNUNET_MessageHeader))
514 ntm = (const struct NotifyTrafficMessage *) msg;
515 em = (const struct GNUNET_MessageHeader *) &ntm[1];
516 if ((GNUNET_NO == h->outbound_hdr_only) &&
517 (msize != ntohs (em->size) + sizeof (struct NotifyTrafficMessage)))
522 if (NULL == h->outbound_notify)
527 h->outbound_notify (h->cls, &ntm->peer, em,
528 GNUNET_TIME_relative_ntoh (ntm->latency),
529 ntohl (ntm->distance));
535 GNUNET_CLIENT_receive (h->client_notifications,
536 &main_notify_handler, h, GNUNET_TIME_UNIT_FOREVER_REL);
541 * Function called when we are ready to transmit our
542 * "START" message (or when this operation timed out).
545 * @param size number of bytes available in buf
546 * @param buf where the callee should write the message
547 * @return number of bytes written to buf
549 static size_t transmit_start (void *cls, size_t size, void *buf);
553 * Function called on the first message received from
554 * the service (contains our public key, etc.).
555 * Should trigger calling the init callback
556 * and then start our regular message processing.
559 * @param msg message received, NULL on timeout or fatal error
562 init_reply_handler (void *cls, const struct GNUNET_MessageHeader *msg)
564 struct GNUNET_CORE_Handle *h = cls;
565 const struct InitReplyMessage *m;
566 GNUNET_CORE_StartupCallback init;
567 struct GNUNET_PeerIdentity my_identity;
570 (ntohs (msg->size) != sizeof (struct InitReplyMessage)) ||
571 (ntohs (msg->type) != GNUNET_MESSAGE_TYPE_CORE_INIT_REPLY))
573 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
575 ("Error connecting to core service (failed to receive `%s' message).\n"),
577 GNUNET_break (msg == NULL);
578 transmit_start (h, 0, NULL);
581 m = (const struct InitReplyMessage *) msg;
582 /* start our message processing loop */
584 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
585 "Successfully connected to core service, starting processing loop.\n");
587 h->currently_down = GNUNET_NO;
588 trigger_next_request (h);
589 GNUNET_CLIENT_receive (h->client_notifications,
590 &main_notify_handler, h, GNUNET_TIME_UNIT_FOREVER_REL);
591 if (NULL != (init = h->init))
593 /* mark so we don't call init on reconnect */
595 GNUNET_CRYPTO_hash (&m->publicKey,
597 GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded),
598 &my_identity.hashPubKey);
599 init (h->cls, h, &my_identity, &m->publicKey);
605 reconnect_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
607 struct GNUNET_CORE_Handle *h = cls;
608 h->reconnect_task = GNUNET_SCHEDULER_NO_TASK;
614 * Function called when we are ready to transmit our
615 * "START" message (or when this operation timed out).
618 * @param size number of bytes available in buf
619 * @param buf where the callee should write the message
620 * @return number of bytes written to buf
623 transmit_start (void *cls, size_t size, void *buf)
625 struct GNUNET_CORE_Handle *h = cls;
626 struct InitMessage *init;
631 struct GNUNET_TIME_Relative delay;
636 if ((h->init == NULL) ||
637 (GNUNET_TIME_absolute_get ().value < h->startup_timeout.value))
639 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
640 _("Failed to connect to core service, retrying.\n"));
641 delay = GNUNET_TIME_absolute_get_remaining (h->startup_timeout);
642 if ((h->init == NULL) || (delay.value > 1000))
643 delay = GNUNET_TIME_UNIT_SECONDS;
646 GNUNET_TIME_relative_to_absolute (GNUNET_TIME_UNIT_MINUTES);
648 GNUNET_SCHEDULER_add_delayed (h->sched,
649 delay, &reconnect_task, h);
652 /* timeout on initial connect */
653 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
654 _("Failed to connect to core service, giving up.\n"));
655 h->init (h->cls, NULL, NULL, NULL);
656 GNUNET_CORE_disconnect (h);
659 msize = h->hcnt * sizeof (uint16_t) + sizeof (struct InitMessage);
660 GNUNET_assert (size >= msize);
662 init->header.type = htons (GNUNET_MESSAGE_TYPE_CORE_INIT);
663 init->header.size = htons (msize);
664 opt = GNUNET_CORE_OPTION_NOTHING;
665 if (h->pre_connects != NULL)
666 opt |= GNUNET_CORE_OPTION_SEND_PRE_CONNECT;
667 if (h->connects != NULL)
668 opt |= GNUNET_CORE_OPTION_SEND_CONNECT;
669 if (h->disconnects != NULL)
670 opt |= GNUNET_CORE_OPTION_SEND_DISCONNECT;
671 if (h->inbound_notify != NULL)
673 if (h->inbound_hdr_only)
674 opt |= GNUNET_CORE_OPTION_SEND_HDR_INBOUND;
676 opt |= GNUNET_CORE_OPTION_SEND_FULL_INBOUND;
678 if (h->outbound_notify != NULL)
680 if (h->outbound_hdr_only)
681 opt |= GNUNET_CORE_OPTION_SEND_HDR_OUTBOUND;
683 opt |= GNUNET_CORE_OPTION_SEND_FULL_OUTBOUND;
685 init->options = htonl (opt);
686 ts = (uint16_t *) & init[1];
687 for (hpos = 0; hpos < h->hcnt; hpos++)
688 ts[hpos] = htons (h->handlers[hpos].type);
689 GNUNET_CLIENT_receive (h->client_notifications,
692 GNUNET_TIME_absolute_get_remaining
693 (h->startup_timeout));
694 return sizeof (struct InitMessage) + h->hcnt * sizeof (uint16_t);
699 * Connect to the core service. Note that the connection may
700 * complete (or fail) asynchronously.
702 * @param sched scheduler to use
703 * @param cfg configuration to use
704 * @param timeout after how long should we give up trying to connect to the core service?
705 * @param cls closure for the various callbacks that follow (including handlers in the handlers array)
706 * @param init callback to call on timeout or once we have successfully
707 * connected to the core service; note that timeout is only meaningful if init is not NULL
708 * @param pre_connects function to call on peer pre-connect (no session key yet), can be NULL
709 * @param connects function to call on peer connect, can be NULL
710 * @param disconnects function to call on peer disconnect / timeout, can be NULL
711 * @param inbound_notify function to call for all inbound messages, can be NULL
712 * @param inbound_hdr_only set to GNUNET_YES if inbound_notify will only read the
713 * GNUNET_MessageHeader and hence we do not need to give it the full message;
714 * can be used to improve efficiency, ignored if inbound_notify is NULLL
715 * @param outbound_notify function to call for all outbound messages, can be NULL
716 * @param outbound_hdr_only set to GNUNET_YES if outbound_notify will only read the
717 * GNUNET_MessageHeader and hence we do not need to give it the full message
718 * can be used to improve efficiency, ignored if outbound_notify is NULLL
719 * @param handlers callbacks for messages we care about, NULL-terminated
720 * @return handle to the core service (only useful for disconnect until 'init' is called);
721 * NULL on error (in this case, init is never called)
723 struct GNUNET_CORE_Handle *
724 GNUNET_CORE_connect (struct GNUNET_SCHEDULER_Handle *sched,
725 const struct GNUNET_CONFIGURATION_Handle *cfg,
726 struct GNUNET_TIME_Relative timeout,
728 GNUNET_CORE_StartupCallback init,
729 GNUNET_CORE_ConnectEventHandler pre_connects,
730 GNUNET_CORE_ConnectEventHandler connects,
731 GNUNET_CORE_DisconnectEventHandler disconnects,
732 GNUNET_CORE_MessageCallback inbound_notify,
733 int inbound_hdr_only,
734 GNUNET_CORE_MessageCallback outbound_notify,
735 int outbound_hdr_only,
736 const struct GNUNET_CORE_MessageHandler *handlers)
738 struct GNUNET_CORE_Handle *h;
740 h = GNUNET_malloc (sizeof (struct GNUNET_CORE_Handle));
745 h->pre_connects = pre_connects;
746 h->connects = connects;
747 h->disconnects = disconnects;
748 h->inbound_notify = inbound_notify;
749 h->outbound_notify = outbound_notify;
750 h->inbound_hdr_only = inbound_hdr_only;
751 h->outbound_hdr_only = outbound_hdr_only;
752 h->handlers = handlers;
753 h->client_notifications = GNUNET_CLIENT_connect (sched, "core", cfg);
754 if (h->client_notifications == NULL)
759 h->startup_timeout = GNUNET_TIME_relative_to_absolute (timeout);
761 while (handlers[h->hcnt].callback != NULL)
763 GNUNET_assert (h->hcnt <
764 (GNUNET_SERVER_MAX_MESSAGE_SIZE -
765 sizeof (struct InitMessage)) / sizeof (uint16_t));
767 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
768 "Trying to connect to core service in next %llu ms.\n",
772 GNUNET_CLIENT_notify_transmit_ready (h->client_notifications,
773 sizeof (struct InitMessage) +
774 sizeof (uint16_t) * h->hcnt, timeout,
782 * Disconnect from the core service.
784 * @param handle connection to core to disconnect
787 GNUNET_CORE_disconnect (struct GNUNET_CORE_Handle *handle)
789 if (handle->th != NULL)
790 GNUNET_CLIENT_notify_transmit_ready_cancel (handle->th);
791 if (handle->solicit_transmit_req != NULL)
792 GNUNET_CORE_notify_transmit_ready_cancel (handle->solicit_transmit_req);
793 if (handle->reconnect_task != GNUNET_SCHEDULER_NO_TASK)
794 GNUNET_SCHEDULER_cancel (handle->sched, handle->reconnect_task);
795 if (handle->client_notifications != NULL)
796 GNUNET_CLIENT_disconnect (handle->client_notifications, GNUNET_NO);
797 GNUNET_free_non_null (handle->solicit_buffer);
798 GNUNET_free (handle);
803 * Build the message requesting data transmission.
806 produce_send (void *cls, size_t size, void *buf)
808 struct GNUNET_CORE_TransmitHandle *th = cls;
809 struct GNUNET_CORE_Handle *h;
810 struct SendMessage *sm;
812 GNUNET_CONNECTION_TransmitReadyNotify notify;
818 /* timeout or error */
820 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
821 "P2P transmission request for `%4s' timed out.\n",
822 GNUNET_i2s(&th->peer));
824 GNUNET_assert (0 == th->notify (th->notify_cls, 0, NULL));
825 GNUNET_CORE_notify_transmit_ready_cancel (th);
826 trigger_next_request (h);
830 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
831 "Preparing for P2P transmission to `%4s'.\n",
832 GNUNET_i2s(&th->peer));
834 GNUNET_assert (th->timeout_task != GNUNET_SCHEDULER_NO_TASK);
835 sm = (struct SendMessage *) buf;
836 sm->header.type = htons (GNUNET_MESSAGE_TYPE_CORE_SEND);
837 sm->priority = htonl (th->priority);
838 sm->deadline = GNUNET_TIME_absolute_hton (th->timeout);
841 notify_cls = th->notify_cls;
842 GNUNET_CORE_notify_transmit_ready_cancel (th);
843 trigger_next_request (h);
844 GNUNET_assert (size >= sizeof (struct SendMessage));
845 dt = notify (notify_cls, size - sizeof (struct SendMessage), &sm[1]);
849 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
850 "Size of clients message to peer %s is 0!\n",
851 GNUNET_i2s(&th->peer));
853 /* client decided to send nothing! */
856 GNUNET_assert (dt >= sizeof (struct GNUNET_MessageHeader));
857 sm->header.size = htons (dt + sizeof (struct SendMessage));
858 GNUNET_assert (dt + sizeof (struct SendMessage) <= size);
859 return dt + sizeof (struct SendMessage);
864 * Ask the core to call "notify" once it is ready to transmit the
865 * given number of bytes to the specified "target". If we are not yet
866 * connected to the specified peer, a call to this function will cause
867 * us to try to establish a connection.
869 * @param handle connection to core service
870 * @param priority how important is the message?
871 * @param maxdelay how long can the message wait?
872 * @param target who should receive the message,
873 * use NULL for this peer (loopback)
874 * @param notify_size how many bytes of buffer space does notify want?
875 * @param notify function to call when buffer space is available
876 * @param notify_cls closure for notify
877 * @return non-NULL if the notify callback was queued,
878 * NULL if we can not even queue the request (insufficient
879 * memory); if NULL is returned, "notify" will NOT be called.
881 struct GNUNET_CORE_TransmitHandle *
882 GNUNET_CORE_notify_transmit_ready (struct GNUNET_CORE_Handle *handle,
883 unsigned int priority,
884 struct GNUNET_TIME_Relative maxdelay,
885 const struct GNUNET_PeerIdentity *target,
887 GNUNET_CONNECTION_TransmitReadyNotify notify,
890 struct GNUNET_CORE_TransmitHandle *th;
892 GNUNET_assert (notify_size + sizeof (struct SendMessage) <
893 GNUNET_SERVER_MAX_MESSAGE_SIZE);
894 th = GNUNET_malloc (sizeof (struct GNUNET_CORE_TransmitHandle));
897 th->prev = handle->pending_tail;
898 if (handle->pending_tail == NULL)
899 handle->pending_head = th;
901 handle->pending_tail->next = th;
902 th->get_message = &produce_send;
903 th->get_message_cls = th;
905 th->notify_cls = notify_cls;
907 th->timeout = GNUNET_TIME_relative_to_absolute (maxdelay);
908 th->timeout_task = GNUNET_SCHEDULER_add_delayed (handle->sched,
910 &timeout_request, th);
911 th->priority = priority;
912 th->msize = sizeof (struct SendMessage) + notify_size;
913 /* was the request queue previously empty? */
914 if ( (handle->pending_head == th) &&
915 (handle->th == NULL) )
916 trigger_next_request (handle);
922 * Cancel the specified transmission-ready notification.
924 * @param h handle that was returned by "notify_transmit_ready".
927 GNUNET_CORE_notify_transmit_ready_cancel (struct GNUNET_CORE_TransmitHandle
930 struct GNUNET_CORE_Handle *handle = h->ch;
932 if (handle->submitted == h)
934 handle->submitted = NULL;
939 handle->pending_head = h->next;
941 h->prev->next = h->next;
943 handle->pending_tail = h->prev;
945 h->next->prev = h->prev;
947 if (h->timeout_task != GNUNET_SCHEDULER_NO_TASK)
948 GNUNET_SCHEDULER_cancel (handle->sched, h->timeout_task);
953 /* end of core_api.c */