2 This file is part of GNUnet.
3 (C) 2009 Christian Grothoff (and other contributing authors)
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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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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.
92 struct GNUNET_CLIENT_Connection *client;
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);
267 h->currently_down = GNUNET_YES;
268 h->client = GNUNET_CLIENT_connect (h->sched, "core", h->cfg);
269 h->th = GNUNET_CLIENT_notify_transmit_ready (h->client,
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;
314 th = h->pending_head;
317 timeout_request (th, NULL);
320 /* create new timeout task (in case core takes too long to respond!) */
321 th->timeout_task = GNUNET_SCHEDULER_add_delayed (h->sched,
322 GNUNET_TIME_absolute_get_remaining
324 &timeout_request, th);
325 /* remove th from doubly-linked pending list, move to submitted */
326 GNUNET_assert (th->prev == NULL);
327 h->pending_head = th->next;
328 if (th->next == NULL)
329 h->pending_tail = NULL;
331 th->next->prev = NULL;
332 GNUNET_assert (h->submitted == NULL);
334 GNUNET_assert (size >= th->msize);
335 ret = th->get_message (th->get_message_cls, size, buf);
336 GNUNET_assert (ret <= size);
342 * Check the list of pending requests, send the next
346 trigger_next_request (struct GNUNET_CORE_Handle *h)
348 struct GNUNET_CORE_TransmitHandle *th;
349 if (h->currently_down)
350 return; /* connection temporarily down */
351 if (NULL == (th = h->pending_head))
352 return; /* no requests pending */
353 GNUNET_assert (NULL == h->th);
354 if (GNUNET_SCHEDULER_NO_TASK != th->timeout_task)
356 GNUNET_SCHEDULER_cancel (h->sched, th->timeout_task);
357 th->timeout_task = GNUNET_SCHEDULER_NO_TASK;
359 h->th = GNUNET_CLIENT_notify_transmit_ready (h->client,
361 GNUNET_TIME_absolute_get_remaining
370 * Handler for most messages received from the core.
372 * @param cls our "struct GNUNET_CORE_Handle"
373 * @param msg the message received from the core service
376 main_handler (void *cls, const struct GNUNET_MessageHeader *msg)
378 struct GNUNET_CORE_Handle *h = cls;
380 const struct ConnectNotifyMessage *cnm;
381 const struct NotifyTrafficMessage *ntm;
382 const struct ConfigurationInfoMessage *cim;
383 const struct GNUNET_MessageHeader *em;
386 const struct GNUNET_CORE_MessageHandler *mh;
390 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
392 ("Client was disconnected from core service, trying to reconnect.\n"));
396 msize = ntohs (msg->size);
398 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
399 "Processing message of type %u and size %u from core service\n",
400 ntohs (msg->type), msize);
402 switch (ntohs (msg->type))
404 case GNUNET_MESSAGE_TYPE_CORE_NOTIFY_PRE_CONNECT:
405 if (NULL == h->pre_connects)
410 if (msize != sizeof (struct ConnectNotifyMessage))
415 cnm = (const struct ConnectNotifyMessage *) msg;
416 h->pre_connects (h->cls,
418 GNUNET_TIME_relative_ntoh (cnm->latency),
419 ntohl (cnm->distance));
421 case GNUNET_MESSAGE_TYPE_CORE_NOTIFY_CONNECT:
422 if (NULL == h->connects)
427 if (msize != sizeof (struct ConnectNotifyMessage))
432 cnm = (const struct ConnectNotifyMessage *) msg;
435 GNUNET_TIME_relative_ntoh (cnm->latency),
436 ntohl (cnm->distance));
438 case GNUNET_MESSAGE_TYPE_CORE_NOTIFY_DISCONNECT:
439 if (NULL == h->disconnects)
444 if (msize != sizeof (struct ConnectNotifyMessage))
449 cnm = (const struct ConnectNotifyMessage *) msg;
450 h->disconnects (h->cls,
453 case GNUNET_MESSAGE_TYPE_CORE_NOTIFY_INBOUND:
455 sizeof (struct NotifyTrafficMessage) +
456 sizeof (struct GNUNET_MessageHeader))
461 ntm = (const struct NotifyTrafficMessage *) msg;
462 em = (const struct GNUNET_MessageHeader *) &ntm[1];
464 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
465 "Received message of type %u from peer `%4s'\n",
466 ntohs (em->type), GNUNET_i2s (&ntm->peer));
468 if ((GNUNET_NO == h->inbound_hdr_only) &&
469 (msize != ntohs (em->size) + sizeof (struct NotifyTrafficMessage)))
474 et = ntohs (em->type);
475 for (hpos = 0; hpos < h->hcnt; hpos++)
477 mh = &h->handlers[hpos];
480 if ((mh->expected_size != ntohs (em->size)) &&
481 (mh->expected_size != 0))
487 h->handlers[hpos].callback (h->cls, &ntm->peer, em,
488 GNUNET_TIME_relative_ntoh (ntm->latency),
489 ntohl (ntm->distance)))
491 /* error in processing, disconnect ! */
496 if (NULL != h->inbound_notify)
497 h->inbound_notify (h->cls, &ntm->peer, em,
498 GNUNET_TIME_relative_ntoh (ntm->latency),
499 ntohl (ntm->distance));
501 case GNUNET_MESSAGE_TYPE_CORE_NOTIFY_OUTBOUND:
503 sizeof (struct NotifyTrafficMessage) +
504 sizeof (struct GNUNET_MessageHeader))
509 ntm = (const struct NotifyTrafficMessage *) msg;
510 em = (const struct GNUNET_MessageHeader *) &ntm[1];
511 if ((GNUNET_NO == h->outbound_hdr_only) &&
512 (msize != ntohs (em->size) + sizeof (struct NotifyTrafficMessage)))
517 if (NULL == h->outbound_notify)
522 h->outbound_notify (h->cls, &ntm->peer, em,
523 GNUNET_TIME_relative_ntoh (ntm->latency),
524 ntohl (ntm->distance));
526 case GNUNET_MESSAGE_TYPE_CORE_CONFIGURATION_INFO:
527 if (msize != sizeof (struct ConfigurationInfoMessage))
532 if (NULL == h->submitted)
534 cim = (const struct ConfigurationInfoMessage *) msg;
536 /* process configuration data */
537 if (h->submitted->info != NULL)
538 h->submitted->info (h->submitted->info_cls,
541 ntohl (cim->bpm_out),
542 (int) ntohl (cim->reserved_amount),
544 /* done, clean up! */
545 GNUNET_CORE_notify_transmit_ready_cancel (h->submitted); // HUH?
546 trigger_next_request (h);
552 GNUNET_CLIENT_receive (h->client,
553 &main_handler, h, GNUNET_TIME_UNIT_FOREVER_REL);
559 * Function called when we are ready to transmit our
560 * "START" message (or when this operation timed out).
563 * @param size number of bytes available in buf
564 * @param buf where the callee should write the message
565 * @return number of bytes written to buf
567 static size_t transmit_start (void *cls, size_t size, void *buf);
571 * Function called on the first message received from
572 * the service (contains our public key, etc.).
573 * Should trigger calling the init callback
574 * and then start our regular message processing.
577 * @param msg message received, NULL on timeout or fatal error
580 init_reply_handler (void *cls, const struct GNUNET_MessageHeader *msg)
582 struct GNUNET_CORE_Handle *h = cls;
583 const struct InitReplyMessage *m;
584 GNUNET_CORE_StartupCallback init;
585 struct GNUNET_PeerIdentity my_identity;
588 (ntohs (msg->size) != sizeof (struct InitReplyMessage)) ||
589 (ntohs (msg->type) != GNUNET_MESSAGE_TYPE_CORE_INIT_REPLY))
591 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
593 ("Error connecting to core service (failed to receive `%s' message).\n"),
595 GNUNET_break (msg == NULL);
596 transmit_start (h, 0, NULL);
599 m = (const struct InitReplyMessage *) msg;
600 /* start our message processing loop */
602 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
604 ("Successfully connected to core service, starting processing loop.\n"));
606 h->currently_down = GNUNET_NO;
607 trigger_next_request (h);
608 GNUNET_CLIENT_receive (h->client,
609 &main_handler, h, GNUNET_TIME_UNIT_FOREVER_REL);
610 if (NULL != (init = h->init))
612 /* mark so we don't call init on reconnect */
615 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
616 _("Successfully connected to core service.\n"));
618 GNUNET_CRYPTO_hash (&m->publicKey,
620 GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded),
621 &my_identity.hashPubKey);
622 init (h->cls, h, &my_identity, &m->publicKey);
628 reconnect_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
630 struct GNUNET_CORE_Handle *h = cls;
631 h->reconnect_task = GNUNET_SCHEDULER_NO_TASK;
637 * Function called when we are ready to transmit our
638 * "START" message (or when this operation timed out).
641 * @param size number of bytes available in buf
642 * @param buf where the callee should write the message
643 * @return number of bytes written to buf
646 transmit_start (void *cls, size_t size, void *buf)
648 struct GNUNET_CORE_Handle *h = cls;
649 struct InitMessage *init;
654 struct GNUNET_TIME_Relative delay;
659 if ((h->init == NULL) ||
660 (GNUNET_TIME_absolute_get ().value < h->startup_timeout.value))
662 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
663 _("Failed to connect to core service, retrying.\n"));
664 delay = GNUNET_TIME_absolute_get_remaining (h->startup_timeout);
665 if ((h->init == NULL) || (delay.value > 1000))
666 delay = GNUNET_TIME_UNIT_SECONDS;
669 GNUNET_TIME_relative_to_absolute (GNUNET_TIME_UNIT_MINUTES);
671 GNUNET_SCHEDULER_add_delayed (h->sched,
672 delay, &reconnect_task, h);
675 /* timeout on initial connect */
676 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
677 _("Failed to connect to core service, giving up.\n"));
678 h->init (h->cls, NULL, NULL, NULL);
679 GNUNET_CORE_disconnect (h);
682 msize = h->hcnt * sizeof (uint16_t) + sizeof (struct InitMessage);
683 GNUNET_assert (size >= msize);
685 init->header.type = htons (GNUNET_MESSAGE_TYPE_CORE_INIT);
686 init->header.size = htons (msize);
687 opt = GNUNET_CORE_OPTION_NOTHING;
688 if (h->pre_connects != NULL)
689 opt |= GNUNET_CORE_OPTION_SEND_PRE_CONNECT;
690 if (h->connects != NULL)
691 opt |= GNUNET_CORE_OPTION_SEND_CONNECT;
692 if (h->disconnects != NULL)
693 opt |= GNUNET_CORE_OPTION_SEND_DISCONNECT;
694 if (h->inbound_notify != NULL)
696 if (h->inbound_hdr_only)
697 opt |= GNUNET_CORE_OPTION_SEND_HDR_INBOUND;
699 opt |= GNUNET_CORE_OPTION_SEND_FULL_INBOUND;
701 if (h->outbound_notify != NULL)
703 if (h->outbound_hdr_only)
704 opt |= GNUNET_CORE_OPTION_SEND_HDR_OUTBOUND;
706 opt |= GNUNET_CORE_OPTION_SEND_FULL_OUTBOUND;
708 init->options = htonl (opt);
709 ts = (uint16_t *) & init[1];
710 for (hpos = 0; hpos < h->hcnt; hpos++)
711 ts[hpos] = htons (h->handlers[hpos].type);
712 GNUNET_CLIENT_receive (h->client,
715 GNUNET_TIME_absolute_get_remaining
716 (h->startup_timeout));
717 return sizeof (struct InitMessage) + h->hcnt * sizeof (uint16_t);
722 * Connect to the core service. Note that the connection may
723 * complete (or fail) asynchronously.
725 * @param sched scheduler to use
726 * @param cfg configuration to use
727 * @param timeout after how long should we give up trying to connect to the core service?
728 * @param cls closure for the various callbacks that follow (including handlers in the handlers array)
729 * @param init callback to call on timeout or once we have successfully
730 * connected to the core service; note that timeout is only meaningful if init is not NULL
731 * @param pre_connects function to call on peer pre-connect (no session key yet), can be NULL
732 * @param connects function to call on peer connect, can be NULL
733 * @param disconnects function to call on peer disconnect / timeout, can be NULL
734 * @param inbound_notify function to call for all inbound messages, can be NULL
735 * @param inbound_hdr_only set to GNUNET_YES if inbound_notify will only read the
736 * GNUNET_MessageHeader and hence we do not need to give it the full message;
737 * can be used to improve efficiency, ignored if inbound_notify is NULLL
738 * @param outbound_notify function to call for all outbound messages, can be NULL
739 * @param outbound_hdr_only set to GNUNET_YES if outbound_notify will only read the
740 * GNUNET_MessageHeader and hence we do not need to give it the full message
741 * can be used to improve efficiency, ignored if outbound_notify is NULLL
742 * @param handlers callbacks for messages we care about, NULL-terminated
743 * @return handle to the core service (only useful for disconnect until 'init' is called);
744 * NULL on error (in this case, init is never called)
746 struct GNUNET_CORE_Handle *
747 GNUNET_CORE_connect (struct GNUNET_SCHEDULER_Handle *sched,
748 const struct GNUNET_CONFIGURATION_Handle *cfg,
749 struct GNUNET_TIME_Relative timeout,
751 GNUNET_CORE_StartupCallback init,
752 GNUNET_CORE_ConnectEventHandler pre_connects,
753 GNUNET_CORE_ConnectEventHandler connects,
754 GNUNET_CORE_DisconnectEventHandler disconnects,
755 GNUNET_CORE_MessageCallback inbound_notify,
756 int inbound_hdr_only,
757 GNUNET_CORE_MessageCallback outbound_notify,
758 int outbound_hdr_only,
759 const struct GNUNET_CORE_MessageHandler *handlers)
761 struct GNUNET_CORE_Handle *h;
763 h = GNUNET_malloc (sizeof (struct GNUNET_CORE_Handle));
768 h->pre_connects = pre_connects;
769 h->connects = connects;
770 h->disconnects = disconnects;
771 h->inbound_notify = inbound_notify;
772 h->outbound_notify = outbound_notify;
773 h->inbound_hdr_only = inbound_hdr_only;
774 h->outbound_hdr_only = outbound_hdr_only;
775 h->handlers = handlers;
776 h->client = GNUNET_CLIENT_connect (sched, "core", cfg);
777 if (h->client == NULL)
782 h->startup_timeout = GNUNET_TIME_relative_to_absolute (timeout);
784 while (handlers[h->hcnt].callback != NULL)
786 GNUNET_assert (h->hcnt <
787 (GNUNET_SERVER_MAX_MESSAGE_SIZE -
788 sizeof (struct InitMessage)) / sizeof (uint16_t));
790 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
791 "Trying to connect to core service in next %llu ms.\n",
795 GNUNET_CLIENT_notify_transmit_ready (h->client,
796 sizeof (struct InitMessage) +
797 sizeof (uint16_t) * h->hcnt, timeout,
805 * Disconnect from the core service.
807 * @param handle connection to core to disconnect
810 GNUNET_CORE_disconnect (struct GNUNET_CORE_Handle *handle)
812 if (handle->th != NULL)
813 GNUNET_CLIENT_notify_transmit_ready_cancel (handle->th);
814 if (handle->solicit_transmit_req != NULL)
815 GNUNET_CORE_notify_transmit_ready_cancel (handle->solicit_transmit_req);
816 if (handle->reconnect_task != GNUNET_SCHEDULER_NO_TASK)
817 GNUNET_SCHEDULER_cancel (handle->sched, handle->reconnect_task);
818 GNUNET_CLIENT_disconnect (handle->client);
819 GNUNET_free_non_null (handle->solicit_buffer);
820 GNUNET_free (handle);
825 * Build the message requesting data transmission.
828 produce_send (void *cls, size_t size, void *buf)
830 struct GNUNET_CORE_TransmitHandle *th = cls;
831 struct GNUNET_CORE_Handle *h;
832 struct SendMessage *sm;
834 GNUNET_CONNECTION_TransmitReadyNotify notify;
840 /* timeout or error */
842 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
843 "P2P transmission request for `%4s' timed out.\n",
844 GNUNET_i2s(&th->peer));
846 GNUNET_assert (0 == th->notify (th->notify_cls, 0, NULL));
847 GNUNET_CORE_notify_transmit_ready_cancel (th);
848 trigger_next_request (h);
852 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
853 "Preparing for P2P transmission to `%4s'.\n",
854 GNUNET_i2s(&th->peer));
856 GNUNET_assert (th->timeout_task != GNUNET_SCHEDULER_NO_TASK);
857 sm = (struct SendMessage *) buf;
858 sm->header.type = htons (GNUNET_MESSAGE_TYPE_CORE_SEND);
859 sm->priority = htonl (th->priority);
860 sm->deadline = GNUNET_TIME_absolute_hton (th->timeout);
863 notify_cls = th->notify_cls;
864 GNUNET_CORE_notify_transmit_ready_cancel (th);
865 trigger_next_request (h);
866 GNUNET_assert (size >= sizeof (struct SendMessage));
867 dt = notify (notify_cls, size - sizeof (struct SendMessage), &sm[1]);
870 /* client decided to send nothing! */
873 GNUNET_assert (dt >= sizeof (struct GNUNET_MessageHeader));
874 sm->header.size = htons (dt + sizeof (struct SendMessage));
875 GNUNET_assert (dt + sizeof (struct SendMessage) < size);
876 return dt + sizeof (struct SendMessage);
881 * Ask the core to call "notify" once it is ready to transmit the
882 * given number of bytes to the specified "target". If we are not yet
883 * connected to the specified peer, a call to this function will cause
884 * us to try to establish a connection.
886 * @param handle connection to core service
887 * @param priority how important is the message?
888 * @param maxdelay how long can the message wait?
889 * @param target who should receive the message,
890 * use NULL for this peer (loopback)
891 * @param notify_size how many bytes of buffer space does notify want?
892 * @param notify function to call when buffer space is available
893 * @param notify_cls closure for notify
894 * @return non-NULL if the notify callback was queued,
895 * NULL if we can not even queue the request (insufficient
896 * memory); if NULL is returned, "notify" will NOT be called.
898 struct GNUNET_CORE_TransmitHandle *
899 GNUNET_CORE_notify_transmit_ready (struct GNUNET_CORE_Handle *handle,
900 unsigned int priority,
901 struct GNUNET_TIME_Relative maxdelay,
902 const struct GNUNET_PeerIdentity *target,
904 GNUNET_CONNECTION_TransmitReadyNotify notify,
907 struct GNUNET_CORE_TransmitHandle *th;
909 GNUNET_assert (notify_size + sizeof (struct SendMessage) <
910 GNUNET_SERVER_MAX_MESSAGE_SIZE);
911 th = GNUNET_malloc (sizeof (struct GNUNET_CORE_TransmitHandle));
914 th->prev = handle->pending_tail;
915 if (handle->pending_tail == NULL)
916 handle->pending_head = th;
918 handle->pending_tail->next = th;
919 th->get_message = &produce_send;
920 th->get_message_cls = th;
922 th->notify_cls = notify_cls;
924 th->timeout = GNUNET_TIME_relative_to_absolute (maxdelay);
925 th->timeout_task = GNUNET_SCHEDULER_add_delayed (handle->sched,
927 &timeout_request, th);
928 th->priority = priority;
929 th->msize = sizeof (struct SendMessage) + notify_size;
930 /* was the request queue previously empty? */
931 if ( (handle->pending_head == th) &&
932 (handle->th == NULL) )
933 trigger_next_request (handle);
939 * Cancel the specified transmission-ready notification.
941 * @param h handle that was returned by "notify_transmit_ready".
944 GNUNET_CORE_notify_transmit_ready_cancel (struct GNUNET_CORE_TransmitHandle
947 struct GNUNET_CORE_Handle *handle = h->ch;
949 if (handle->submitted == h)
951 handle->submitted = NULL;
956 handle->pending_head = h->next;
958 h->prev->next = h->next;
960 handle->pending_tail = h->prev;
962 h->next->prev = h->prev;
964 if (h->timeout_task != GNUNET_SCHEDULER_NO_TASK)
965 GNUNET_SCHEDULER_cancel (handle->sched, h->timeout_task);
970 /* end of core_api.c */