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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12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 General Public License for more details.
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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 configuration request, pointer
196 * to the information callback; otherwise NULL.
198 GNUNET_CORE_PeerConfigurationInfoCallback info;
206 * If this entry is for a transmission request, pointer
207 * to the notify callback; otherwise NULL.
209 GNUNET_CONNECTION_TransmitReadyNotify notify;
212 * Closure for notify.
217 * Peer the request is about.
219 struct GNUNET_PeerIdentity peer;
222 * Timeout for this handle.
224 struct GNUNET_TIME_Absolute timeout;
227 * ID of timeout task.
229 GNUNET_SCHEDULER_TaskIdentifier timeout_task;
232 * How important is this message?
237 * Size of this request.
246 * Function called when we are ready to transmit our
247 * "START" message (or when this operation timed out).
250 * @param size number of bytes available in buf
251 * @param buf where the callee should write the message
252 * @return number of bytes written to buf
254 static size_t transmit_start (void *cls, size_t size, void *buf);
258 * Our current client connection went down. Clean it up
259 * and try to reconnect!
261 * @param h our handle to the core service
264 reconnect (struct GNUNET_CORE_Handle *h)
266 GNUNET_CLIENT_disconnect (h->client_notifications);
267 h->currently_down = GNUNET_YES;
268 h->client_notifications = GNUNET_CLIENT_connect (h->sched, "core", h->cfg);
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 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
291 "Transmission request timed out.\n");
292 th->timeout_task = GNUNET_SCHEDULER_NO_TASK;
293 GNUNET_assert (0 == th->get_message (th->get_message_cls, 0, NULL));
298 * Function called when we are ready to transmit a request from our
299 * request list (or when this operation timed out).
302 * @param size number of bytes available in buf
303 * @param buf where the callee should write the message
304 * @return number of bytes written to buf
307 request_start (void *cls, size_t size, void *buf)
309 struct GNUNET_CORE_Handle *h = cls;
310 struct GNUNET_CORE_TransmitHandle *th;
313 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
314 "request_start called\n");
317 th = h->pending_head;
320 timeout_request (th, NULL);
323 /* create new timeout task (in case core takes too long to respond!) */
324 th->timeout_task = GNUNET_SCHEDULER_add_delayed (h->sched,
325 GNUNET_TIME_absolute_get_remaining
327 &timeout_request, th);
328 /* remove th from doubly-linked pending list, move to submitted */
329 GNUNET_assert (th->prev == NULL);
330 h->pending_head = th->next;
331 if (th->next == NULL)
332 h->pending_tail = NULL;
334 th->next->prev = NULL;
335 GNUNET_assert (h->submitted == NULL);
337 GNUNET_assert (size >= th->msize);
338 ret = th->get_message (th->get_message_cls, size, buf);
339 GNUNET_assert (ret <= size);
345 * Check the list of pending requests, send the next
349 trigger_next_request (struct GNUNET_CORE_Handle *h)
351 struct GNUNET_CORE_TransmitHandle *th;
353 if (h->currently_down)
355 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
356 "\nIn trigger_next_request, connection currently down...\n");
357 return; /* connection temporarily down */
359 if (NULL == (th = h->pending_head))
360 return; /* no requests pending */
361 GNUNET_assert (NULL == h->th);
362 if (GNUNET_SCHEDULER_NO_TASK != th->timeout_task)
364 GNUNET_SCHEDULER_cancel (h->sched, th->timeout_task);
365 th->timeout_task = GNUNET_SCHEDULER_NO_TASK;
367 h->th = GNUNET_CLIENT_notify_transmit_ready (h->client_notifications,
369 GNUNET_TIME_absolute_get_remaining
378 * Handler for notification messages received from the core.
380 * @param cls our "struct GNUNET_CORE_Handle"
381 * @param msg the message received from the core service
384 main_notify_handler (void *cls, const struct GNUNET_MessageHeader *msg)
386 struct GNUNET_CORE_Handle *h = cls;
388 const struct ConnectNotifyMessage *cnm;
389 const struct DisconnectNotifyMessage *dnm;
390 const struct NotifyTrafficMessage *ntm;
391 const struct GNUNET_MessageHeader *em;
394 const struct GNUNET_CORE_MessageHandler *mh;
398 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
400 ("Client was disconnected from core service, trying to reconnect.\n"));
404 msize = ntohs (msg->size);
406 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
407 "Processing message of type %u and size %u from core service\n",
408 ntohs (msg->type), msize);
410 switch (ntohs (msg->type))
412 case GNUNET_MESSAGE_TYPE_CORE_NOTIFY_PRE_CONNECT:
413 if (NULL == h->pre_connects)
418 if (msize != sizeof (struct ConnectNotifyMessage))
423 cnm = (const struct ConnectNotifyMessage *) msg;
424 h->pre_connects (h->cls,
426 GNUNET_TIME_relative_ntoh (cnm->latency),
427 ntohl (cnm->distance));
429 case GNUNET_MESSAGE_TYPE_CORE_NOTIFY_CONNECT:
430 if (NULL == h->connects)
435 if (msize != sizeof (struct ConnectNotifyMessage))
440 cnm = (const struct ConnectNotifyMessage *) msg;
443 GNUNET_TIME_relative_ntoh (cnm->latency),
444 ntohl (cnm->distance));
446 case GNUNET_MESSAGE_TYPE_CORE_NOTIFY_DISCONNECT:
447 if (NULL == h->disconnects)
452 if (msize != sizeof (struct DisconnectNotifyMessage))
457 dnm = (const struct DisconnectNotifyMessage *) msg;
458 h->disconnects (h->cls,
461 case GNUNET_MESSAGE_TYPE_CORE_NOTIFY_INBOUND:
463 sizeof (struct NotifyTrafficMessage) +
464 sizeof (struct GNUNET_MessageHeader))
469 ntm = (const struct NotifyTrafficMessage *) msg;
470 em = (const struct GNUNET_MessageHeader *) &ntm[1];
472 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
473 "Received message of type %u from peer `%4s'\n",
474 ntohs (em->type), GNUNET_i2s (&ntm->peer));
476 if ((GNUNET_NO == h->inbound_hdr_only) &&
477 (msize != ntohs (em->size) + sizeof (struct NotifyTrafficMessage)))
482 et = ntohs (em->type);
483 for (hpos = 0; hpos < h->hcnt; hpos++)
485 mh = &h->handlers[hpos];
488 if ((mh->expected_size != ntohs (em->size)) &&
489 (mh->expected_size != 0))
495 h->handlers[hpos].callback (h->cls, &ntm->peer, em,
496 GNUNET_TIME_relative_ntoh (ntm->latency),
497 ntohl (ntm->distance)))
499 /* error in processing, disconnect ! */
504 if (NULL != h->inbound_notify)
505 h->inbound_notify (h->cls, &ntm->peer, em,
506 GNUNET_TIME_relative_ntoh (ntm->latency),
507 ntohl (ntm->distance));
509 case GNUNET_MESSAGE_TYPE_CORE_NOTIFY_OUTBOUND:
511 sizeof (struct NotifyTrafficMessage) +
512 sizeof (struct GNUNET_MessageHeader))
517 ntm = (const struct NotifyTrafficMessage *) msg;
518 em = (const struct GNUNET_MessageHeader *) &ntm[1];
519 if ((GNUNET_NO == h->outbound_hdr_only) &&
520 (msize != ntohs (em->size) + sizeof (struct NotifyTrafficMessage)))
525 if (NULL == h->outbound_notify)
530 h->outbound_notify (h->cls, &ntm->peer, em,
531 GNUNET_TIME_relative_ntoh (ntm->latency),
532 ntohl (ntm->distance));
538 GNUNET_CLIENT_receive (h->client_notifications,
539 &main_notify_handler, h, GNUNET_TIME_UNIT_FOREVER_REL);
544 * Function called when we are ready to transmit our
545 * "START" message (or when this operation timed out).
548 * @param size number of bytes available in buf
549 * @param buf where the callee should write the message
550 * @return number of bytes written to buf
552 static size_t transmit_start (void *cls, size_t size, void *buf);
556 * Function called on the first message received from
557 * the service (contains our public key, etc.).
558 * Should trigger calling the init callback
559 * and then start our regular message processing.
562 * @param msg message received, NULL on timeout or fatal error
565 init_reply_handler (void *cls, const struct GNUNET_MessageHeader *msg)
567 struct GNUNET_CORE_Handle *h = cls;
568 const struct InitReplyMessage *m;
569 GNUNET_CORE_StartupCallback init;
570 struct GNUNET_PeerIdentity my_identity;
573 (ntohs (msg->size) != sizeof (struct InitReplyMessage)) ||
574 (ntohs (msg->type) != GNUNET_MESSAGE_TYPE_CORE_INIT_REPLY))
576 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
578 ("Error connecting to core service (failed to receive `%s' message).\n"),
580 GNUNET_break (msg == NULL);
581 transmit_start (h, 0, NULL);
584 m = (const struct InitReplyMessage *) msg;
585 /* start our message processing loop */
587 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
589 ("Successfully connected to core service, starting processing loop.\n"));
591 h->currently_down = GNUNET_NO;
592 trigger_next_request (h);
593 GNUNET_CLIENT_receive (h->client_notifications,
594 &main_notify_handler, h, GNUNET_TIME_UNIT_FOREVER_REL);
595 if (NULL != (init = h->init))
597 /* mark so we don't call init on reconnect */
600 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
601 _("Successfully connected to core service.\n"));
603 GNUNET_CRYPTO_hash (&m->publicKey,
605 GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded),
606 &my_identity.hashPubKey);
607 init (h->cls, h, &my_identity, &m->publicKey);
613 reconnect_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
615 struct GNUNET_CORE_Handle *h = cls;
616 h->reconnect_task = GNUNET_SCHEDULER_NO_TASK;
622 * Function called when we are ready to transmit our
623 * "START" message (or when this operation timed out).
626 * @param size number of bytes available in buf
627 * @param buf where the callee should write the message
628 * @return number of bytes written to buf
631 transmit_start (void *cls, size_t size, void *buf)
633 struct GNUNET_CORE_Handle *h = cls;
634 struct InitMessage *init;
639 struct GNUNET_TIME_Relative delay;
644 if ((h->init == NULL) ||
645 (GNUNET_TIME_absolute_get ().value < h->startup_timeout.value))
647 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
648 _("Failed to connect to core service, retrying.\n"));
649 delay = GNUNET_TIME_absolute_get_remaining (h->startup_timeout);
650 if ((h->init == NULL) || (delay.value > 1000))
651 delay = GNUNET_TIME_UNIT_SECONDS;
654 GNUNET_TIME_relative_to_absolute (GNUNET_TIME_UNIT_MINUTES);
656 GNUNET_SCHEDULER_add_delayed (h->sched,
657 delay, &reconnect_task, h);
660 /* timeout on initial connect */
661 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
662 _("Failed to connect to core service, giving up.\n"));
663 h->init (h->cls, NULL, NULL, NULL);
664 GNUNET_CORE_disconnect (h);
667 msize = h->hcnt * sizeof (uint16_t) + sizeof (struct InitMessage);
668 GNUNET_assert (size >= msize);
670 init->header.type = htons (GNUNET_MESSAGE_TYPE_CORE_INIT);
671 init->header.size = htons (msize);
672 opt = GNUNET_CORE_OPTION_NOTHING;
673 if (h->pre_connects != NULL)
674 opt |= GNUNET_CORE_OPTION_SEND_PRE_CONNECT;
675 if (h->connects != NULL)
676 opt |= GNUNET_CORE_OPTION_SEND_CONNECT;
677 if (h->disconnects != NULL)
678 opt |= GNUNET_CORE_OPTION_SEND_DISCONNECT;
679 if (h->inbound_notify != NULL)
681 if (h->inbound_hdr_only)
682 opt |= GNUNET_CORE_OPTION_SEND_HDR_INBOUND;
684 opt |= GNUNET_CORE_OPTION_SEND_FULL_INBOUND;
686 if (h->outbound_notify != NULL)
688 if (h->outbound_hdr_only)
689 opt |= GNUNET_CORE_OPTION_SEND_HDR_OUTBOUND;
691 opt |= GNUNET_CORE_OPTION_SEND_FULL_OUTBOUND;
693 init->options = htonl (opt);
694 ts = (uint16_t *) & init[1];
695 for (hpos = 0; hpos < h->hcnt; hpos++)
696 ts[hpos] = htons (h->handlers[hpos].type);
697 GNUNET_CLIENT_receive (h->client_notifications,
700 GNUNET_TIME_absolute_get_remaining
701 (h->startup_timeout));
702 return sizeof (struct InitMessage) + h->hcnt * sizeof (uint16_t);
707 * Connect to the core service. Note that the connection may
708 * complete (or fail) asynchronously.
710 * @param sched scheduler to use
711 * @param cfg configuration to use
712 * @param timeout after how long should we give up trying to connect to the core service?
713 * @param cls closure for the various callbacks that follow (including handlers in the handlers array)
714 * @param init callback to call on timeout or once we have successfully
715 * connected to the core service; note that timeout is only meaningful if init is not NULL
716 * @param pre_connects function to call on peer pre-connect (no session key yet), can be NULL
717 * @param connects function to call on peer connect, can be NULL
718 * @param disconnects function to call on peer disconnect / timeout, can be NULL
719 * @param inbound_notify function to call for all inbound messages, can be NULL
720 * @param inbound_hdr_only set to GNUNET_YES if inbound_notify will only read the
721 * GNUNET_MessageHeader and hence we do not need to give it the full message;
722 * can be used to improve efficiency, ignored if inbound_notify is NULLL
723 * @param outbound_notify function to call for all outbound messages, can be NULL
724 * @param outbound_hdr_only set to GNUNET_YES if outbound_notify will only read the
725 * GNUNET_MessageHeader and hence we do not need to give it the full message
726 * can be used to improve efficiency, ignored if outbound_notify is NULLL
727 * @param handlers callbacks for messages we care about, NULL-terminated
728 * @return handle to the core service (only useful for disconnect until 'init' is called);
729 * NULL on error (in this case, init is never called)
731 struct GNUNET_CORE_Handle *
732 GNUNET_CORE_connect (struct GNUNET_SCHEDULER_Handle *sched,
733 const struct GNUNET_CONFIGURATION_Handle *cfg,
734 struct GNUNET_TIME_Relative timeout,
736 GNUNET_CORE_StartupCallback init,
737 GNUNET_CORE_ConnectEventHandler pre_connects,
738 GNUNET_CORE_ConnectEventHandler connects,
739 GNUNET_CORE_DisconnectEventHandler disconnects,
740 GNUNET_CORE_MessageCallback inbound_notify,
741 int inbound_hdr_only,
742 GNUNET_CORE_MessageCallback outbound_notify,
743 int outbound_hdr_only,
744 const struct GNUNET_CORE_MessageHandler *handlers)
746 struct GNUNET_CORE_Handle *h;
748 h = GNUNET_malloc (sizeof (struct GNUNET_CORE_Handle));
753 h->pre_connects = pre_connects;
754 h->connects = connects;
755 h->disconnects = disconnects;
756 h->inbound_notify = inbound_notify;
757 h->outbound_notify = outbound_notify;
758 h->inbound_hdr_only = inbound_hdr_only;
759 h->outbound_hdr_only = outbound_hdr_only;
760 h->handlers = handlers;
761 h->client_notifications = GNUNET_CLIENT_connect (sched, "core", cfg);
762 if (h->client_notifications == NULL)
767 h->startup_timeout = GNUNET_TIME_relative_to_absolute (timeout);
769 while (handlers[h->hcnt].callback != NULL)
771 GNUNET_assert (h->hcnt <
772 (GNUNET_SERVER_MAX_MESSAGE_SIZE -
773 sizeof (struct InitMessage)) / sizeof (uint16_t));
775 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
776 "Trying to connect to core service in next %llu ms.\n",
780 GNUNET_CLIENT_notify_transmit_ready (h->client_notifications,
781 sizeof (struct InitMessage) +
782 sizeof (uint16_t) * h->hcnt, timeout,
790 * Disconnect from the core service.
792 * @param handle connection to core to disconnect
795 GNUNET_CORE_disconnect (struct GNUNET_CORE_Handle *handle)
797 if (handle->th != NULL)
798 GNUNET_CLIENT_notify_transmit_ready_cancel (handle->th);
799 if (handle->solicit_transmit_req != NULL)
800 GNUNET_CORE_notify_transmit_ready_cancel (handle->solicit_transmit_req);
801 if (handle->reconnect_task != GNUNET_SCHEDULER_NO_TASK)
802 GNUNET_SCHEDULER_cancel (handle->sched, handle->reconnect_task);
803 GNUNET_CLIENT_disconnect (handle->client_notifications);
804 GNUNET_free_non_null (handle->solicit_buffer);
805 GNUNET_free (handle);
810 * Build the message requesting data transmission.
813 produce_send (void *cls, size_t size, void *buf)
815 struct GNUNET_CORE_TransmitHandle *th = cls;
816 struct GNUNET_CORE_Handle *h;
817 struct SendMessage *sm;
819 GNUNET_CONNECTION_TransmitReadyNotify notify;
825 /* timeout or error */
827 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
828 "P2P transmission request for `%4s' timed out.\n",
829 GNUNET_i2s(&th->peer));
831 GNUNET_assert (0 == th->notify (th->notify_cls, 0, NULL));
832 GNUNET_CORE_notify_transmit_ready_cancel (th);
833 trigger_next_request (h);
837 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
838 "Preparing for P2P transmission to `%4s'.\n",
839 GNUNET_i2s(&th->peer));
841 GNUNET_assert (th->timeout_task != GNUNET_SCHEDULER_NO_TASK);
842 sm = (struct SendMessage *) buf;
843 sm->header.type = htons (GNUNET_MESSAGE_TYPE_CORE_SEND);
844 sm->priority = htonl (th->priority);
845 sm->deadline = GNUNET_TIME_absolute_hton (th->timeout);
848 notify_cls = th->notify_cls;
849 GNUNET_CORE_notify_transmit_ready_cancel (th);
850 trigger_next_request (h);
851 GNUNET_assert (size >= sizeof (struct SendMessage));
852 dt = notify (notify_cls, size - sizeof (struct SendMessage), &sm[1]);
856 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
857 "Size of clients message to peer %s is 0!\n",
858 GNUNET_i2s(&th->peer));
860 /* client decided to send nothing! */
863 GNUNET_assert (dt >= sizeof (struct GNUNET_MessageHeader));
864 sm->header.size = htons (dt + sizeof (struct SendMessage));
865 GNUNET_assert (dt + sizeof (struct SendMessage) <= size);
866 return dt + sizeof (struct SendMessage);
871 * Ask the core to call "notify" once it is ready to transmit the
872 * given number of bytes to the specified "target". If we are not yet
873 * connected to the specified peer, a call to this function will cause
874 * us to try to establish a connection.
876 * @param handle connection to core service
877 * @param priority how important is the message?
878 * @param maxdelay how long can the message wait?
879 * @param target who should receive the message,
880 * use NULL for this peer (loopback)
881 * @param notify_size how many bytes of buffer space does notify want?
882 * @param notify function to call when buffer space is available
883 * @param notify_cls closure for notify
884 * @return non-NULL if the notify callback was queued,
885 * NULL if we can not even queue the request (insufficient
886 * memory); if NULL is returned, "notify" will NOT be called.
888 struct GNUNET_CORE_TransmitHandle *
889 GNUNET_CORE_notify_transmit_ready (struct GNUNET_CORE_Handle *handle,
890 unsigned int priority,
891 struct GNUNET_TIME_Relative maxdelay,
892 const struct GNUNET_PeerIdentity *target,
894 GNUNET_CONNECTION_TransmitReadyNotify notify,
897 struct GNUNET_CORE_TransmitHandle *th;
899 GNUNET_assert (notify_size + sizeof (struct SendMessage) <
900 GNUNET_SERVER_MAX_MESSAGE_SIZE);
901 th = GNUNET_malloc (sizeof (struct GNUNET_CORE_TransmitHandle));
904 th->prev = handle->pending_tail;
905 if (handle->pending_tail == NULL)
906 handle->pending_head = th;
908 handle->pending_tail->next = th;
909 th->get_message = &produce_send;
910 th->get_message_cls = th;
912 th->notify_cls = notify_cls;
914 th->timeout = GNUNET_TIME_relative_to_absolute (maxdelay);
915 th->timeout_task = GNUNET_SCHEDULER_add_delayed (handle->sched,
917 &timeout_request, th);
918 th->priority = priority;
919 th->msize = sizeof (struct SendMessage) + notify_size;
920 /* was the request queue previously empty? */
921 if ( (handle->pending_head == th) &&
922 (handle->th == NULL) )
923 trigger_next_request (handle);
929 * Cancel the specified transmission-ready notification.
931 * @param h handle that was returned by "notify_transmit_ready".
934 GNUNET_CORE_notify_transmit_ready_cancel (struct GNUNET_CORE_TransmitHandle
937 struct GNUNET_CORE_Handle *handle = h->ch;
939 if (handle->submitted == h)
941 handle->submitted = NULL;
946 handle->pending_head = h->next;
948 h->prev->next = h->next;
950 handle->pending_tail = h->prev;
952 h->next->prev = h->prev;
954 if (h->timeout_task != GNUNET_SCHEDULER_NO_TASK)
955 GNUNET_SCHEDULER_cancel (handle->sched, h->timeout_task);
960 /* end of core_api.c */