2 This file is part of GNUnet.
3 (C) 2009, 2010 Christian Grothoff (and other contributing authors)
5 GNUnet is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published
7 by the Free Software Foundation; either version 3, or (at your
8 option) any later version.
10 GNUnet is distributed in the hope that it will be useful, but
11 WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with GNUnet; see the file COPYING. If not, write to the
17 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA.
22 * @file core/core_api.c
23 * @brief core service; this is the main API for encrypted P2P
25 * @author Christian Grothoff
28 * - implement atsi parsing and passing
31 #include "gnunet_constants.h"
32 #include "gnunet_core_service.h"
37 * Information we track for each peer.
43 * We generally do NOT keep peer records in a DLL; this
44 * DLL is only used IF this peer's 'pending_head' message
45 * is ready for transmission.
47 struct PeerRecord *prev;
50 * We generally do NOT keep peer records in a DLL; this
51 * DLL is only used IF this peer's 'pending_head' message
52 * is ready for transmission.
54 struct PeerRecord *next;
57 * Peer the record is about.
59 struct GNUNET_PeerIdentity peer;
62 * Corresponding core handle.
64 struct GNUNET_CORE_Handle *ch;
67 * Head of doubly-linked list of pending requests.
68 * Requests are sorted by deadline *except* for HEAD,
69 * which is only modified upon transmission to core.
71 struct GNUNET_CORE_TransmitHandle *pending_head;
74 * Tail of doubly-linked list of pending requests.
76 struct GNUNET_CORE_TransmitHandle *pending_tail;
79 * Pending callback waiting for peer information, or NULL for none.
81 GNUNET_CORE_PeerConfigurationInfoCallback pcic;
89 * Request information ID for the given pcic (needed in case a
90 * request is cancelled after being submitted to core and a new
91 * one is generated; in this case, we need to avoid matching the
92 * reply to the first (cancelled) request to the second request).
97 * ID of timeout task for the 'pending_head' handle
98 * which is the one with the smallest timeout.
100 GNUNET_SCHEDULER_TaskIdentifier timeout_task;
103 * Current size of the queue of pending requests.
105 unsigned int queue_size;
108 * SendMessageRequest ID generator for this peer.
116 * Entry in a doubly-linked list of control messages to be transmitted
117 * to the core service. Control messages include traffic allocation,
118 * connection requests and of course our initial 'init' request.
120 * The actual message is allocated at the end of this struct.
122 struct ControlMessage
125 * This is a doubly-linked list.
127 struct ControlMessage *next;
130 * This is a doubly-linked list.
132 struct ControlMessage *prev;
135 * Function to run after successful transmission (or call with
136 * reason 'TIMEOUT' on error); called with scheduler context 'NULL'
139 GNUNET_SCHEDULER_Task cont;
142 * Closure for 'cont'.
151 * Context for the core service connection.
153 struct GNUNET_CORE_Handle
157 * Configuration we're using.
159 const struct GNUNET_CONFIGURATION_Handle *cfg;
162 * Closure for the various callbacks.
167 * Function to call once we've handshaked with the core service.
169 GNUNET_CORE_StartupCallback init;
172 * Function to call whenever we're notified about a peer connecting.
174 GNUNET_CORE_ConnectEventHandler connects;
177 * Function to call whenever we're notified about a peer disconnecting.
179 GNUNET_CORE_DisconnectEventHandler disconnects;
182 * Function to call whenever we're notified about a peer changing status.
184 GNUNET_CORE_PeerStatusEventHandler status_events;
187 * Function to call whenever we receive an inbound message.
189 GNUNET_CORE_MessageCallback inbound_notify;
192 * Function to call whenever we receive an outbound message.
194 GNUNET_CORE_MessageCallback outbound_notify;
197 * Function handlers for messages of particular type.
199 const struct GNUNET_CORE_MessageHandler *handlers;
202 * Our connection to the service.
204 struct GNUNET_CLIENT_Connection *client;
207 * Handle for our current transmission request.
209 struct GNUNET_CLIENT_TransmitHandle *cth;
212 * Head of doubly-linked list of pending requests.
214 struct ControlMessage *pending_head;
217 * Tail of doubly-linked list of pending requests.
219 struct ControlMessage *pending_tail;
222 * Head of doubly-linked list of peers that are core-approved
223 * to send their next message.
225 struct PeerRecord *ready_peer_head;
228 * Tail of doubly-linked list of peers that are core-approved
229 * to send their next message.
231 struct PeerRecord *ready_peer_tail;
234 * Hash map listing all of the peers that we are currently
237 struct GNUNET_CONTAINER_MultiHashMap *peers;
240 * Identity of this peer.
242 struct GNUNET_PeerIdentity me;
245 * ID of reconnect task (if any).
247 GNUNET_SCHEDULER_TaskIdentifier reconnect_task;
250 * Current delay we use for re-trying to connect to core.
252 struct GNUNET_TIME_Relative retry_backoff;
255 * Request information ID generator.
260 * Number of messages we are allowed to queue per target.
262 unsigned int queue_size;
265 * Number of entries in the handlers array.
270 * For inbound notifications without a specific handler, do
271 * we expect to only receive headers?
273 int inbound_hdr_only;
276 * For outbound notifications without a specific handler, do
277 * we expect to only receive headers?
279 int outbound_hdr_only;
282 * Are we currently disconnected and hence unable to forward
291 * Handle for a transmission request.
293 struct GNUNET_CORE_TransmitHandle
297 * We keep active transmit handles in a doubly-linked list.
299 struct GNUNET_CORE_TransmitHandle *next;
302 * We keep active transmit handles in a doubly-linked list.
304 struct GNUNET_CORE_TransmitHandle *prev;
307 * Corresponding peer record.
309 struct PeerRecord *peer;
312 * Corresponding SEND_REQUEST message. Only non-NULL
313 * while SEND_REQUEST message is pending.
315 struct ControlMessage *cm;
318 * Function that will be called to get the actual request
319 * (once we are ready to transmit this request to the core).
320 * The function will be called with a NULL buffer to signal
323 GNUNET_CONNECTION_TransmitReadyNotify get_message;
326 * Closure for get_message.
328 void *get_message_cls;
331 * Timeout for this handle.
333 struct GNUNET_TIME_Absolute timeout;
336 * How important is this message?
341 * Size of this request.
346 * Send message request ID for this request.
354 * Our current client connection went down. Clean it up
355 * and try to reconnect!
357 * @param h our handle to the core service
360 reconnect (struct GNUNET_CORE_Handle *h);
364 * Task schedule to try to re-connect to core.
366 * @param cls the 'struct GNUNET_CORE_Handle'
367 * @param tc task context
370 reconnect_task (void *cls,
371 const struct GNUNET_SCHEDULER_TaskContext *tc)
373 struct GNUNET_CORE_Handle *h = cls;
375 h->reconnect_task = GNUNET_SCHEDULER_NO_TASK;
377 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
378 "Connecting to CORE service after delay\n");
385 * Notify clients about disconnect and free
386 * the entry for connected peer.
388 * @param cls the 'struct GNUNET_CORE_Handle*'
389 * @param key the peer identity (not used)
390 * @param value the 'struct PeerRecord' to free.
391 * @return GNUNET_YES (continue)
394 disconnect_and_free_peer_entry (void *cls,
395 const GNUNET_HashCode *key,
398 static struct GNUNET_BANDWIDTH_Value32NBO zero;
399 struct GNUNET_CORE_Handle *h = cls;
400 struct GNUNET_CORE_TransmitHandle *th;
401 struct PeerRecord *pr = value;
402 GNUNET_CORE_PeerConfigurationInfoCallback pcic;
404 while (NULL != (th = pr->pending_head))
406 GNUNET_CONTAINER_DLL_remove (pr->pending_head,
411 th->get_message (th->get_message_cls,
415 if (NULL != (pcic = pr->pcic))
423 if (pr->timeout_task != GNUNET_SCHEDULER_NO_TASK)
425 GNUNET_SCHEDULER_cancel (pr->timeout_task);
426 pr->timeout_task = GNUNET_SCHEDULER_NO_TASK;
428 GNUNET_assert (pr->queue_size == 0);
429 if ( (pr->prev != NULL) ||
430 (pr->next != NULL) ||
431 (h->ready_peer_head == pr) )
432 GNUNET_CONTAINER_DLL_remove (h->ready_peer_head,
435 if (h->disconnects != NULL)
436 h->disconnects (h->cls,
438 GNUNET_assert (GNUNET_YES ==
439 GNUNET_CONTAINER_multihashmap_remove (h->peers,
442 GNUNET_assert (pr->pending_head == NULL);
443 GNUNET_assert (pr->pending_tail == NULL);
444 GNUNET_assert (pr->ch = h);
445 GNUNET_assert (pr->queue_size == 0);
446 GNUNET_assert (pr->timeout_task == GNUNET_SCHEDULER_NO_TASK);
453 * Close down any existing connection to the CORE service and
454 * try re-establishing it later.
456 * @param h our handle
459 reconnect_later (struct GNUNET_CORE_Handle *h)
461 struct ControlMessage *cm;
463 if (h->client != NULL)
465 GNUNET_CLIENT_disconnect (h->client, GNUNET_NO);
467 GNUNET_CONTAINER_multihashmap_iterate (h->peers,
468 &disconnect_and_free_peer_entry,
471 h->currently_down = GNUNET_YES;
472 while (NULL != (cm = h->pending_head))
474 GNUNET_CONTAINER_DLL_remove (h->pending_head,
477 cm->cont (cm->cont_cls, NULL);
480 GNUNET_assert (h->reconnect_task == GNUNET_SCHEDULER_NO_TASK);
481 h->retry_backoff = GNUNET_TIME_relative_min (GNUNET_TIME_UNIT_SECONDS,
483 h->reconnect_task = GNUNET_SCHEDULER_add_delayed (h->retry_backoff,
486 h->retry_backoff = GNUNET_TIME_relative_multiply (h->retry_backoff, 2);
491 * Check the list of pending requests, send the next
494 * @param h core handle
495 * @param ignore_currently_down transmit message even if not initialized?
498 trigger_next_request (struct GNUNET_CORE_Handle *h,
499 int ignore_currently_down);
503 * The given request hit its timeout. Remove from the
504 * doubly-linked list and call the respective continuation.
506 * @param cls the transmit handle of the request that timed out
507 * @param tc context, can be NULL (!)
510 transmission_timeout (void *cls,
511 const struct GNUNET_SCHEDULER_TaskContext *tc);
515 * Control message was sent, mark it as such.
517 * @param cls the 'struct GNUNET_CORE_TransmitHandle*'
518 * @param tc scheduler context
521 mark_control_message_sent (void *cls,
522 const struct GNUNET_SCHEDULER_TaskContext *tc)
524 struct GNUNET_CORE_TransmitHandle *th = cls;
531 * Send a control message to the peer asking for transmission
532 * of the message in the given peer record.
534 * @param pr peer to request transmission to
537 request_next_transmission (struct PeerRecord *pr)
539 struct GNUNET_CORE_Handle *h = pr->ch;
540 struct ControlMessage *cm;
541 struct SendMessageRequest *smr;
542 struct GNUNET_CORE_TransmitHandle *th;
544 if (pr->timeout_task != GNUNET_SCHEDULER_NO_TASK)
546 GNUNET_SCHEDULER_cancel (pr->timeout_task);
547 pr->timeout_task = GNUNET_SCHEDULER_NO_TASK;
549 if (NULL == (th = pr->pending_head))
551 trigger_next_request (h, GNUNET_NO);
554 GNUNET_assert (pr->prev == NULL);
555 GNUNET_assert (pr->next == NULL);
556 pr->timeout_task = GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_absolute_get_remaining (th->timeout),
557 &transmission_timeout,
559 cm = GNUNET_malloc (sizeof (struct ControlMessage) +
560 sizeof (struct SendMessageRequest));
561 cm->cont = &mark_control_message_sent;
564 smr = (struct SendMessageRequest*) &cm[1];
565 smr->header.type = htons (GNUNET_MESSAGE_TYPE_CORE_SEND_REQUEST);
566 smr->header.size = htons (sizeof (struct SendMessageRequest));
567 smr->priority = htonl (th->priority);
568 smr->deadline = GNUNET_TIME_absolute_hton (th->timeout);
569 smr->peer = pr->peer;
570 smr->queue_size = htonl (pr->queue_size);
571 smr->size = htons (th->msize);
572 smr->smr_id = htons (th->smr_id = pr->smr_id_gen++);
573 GNUNET_CONTAINER_DLL_insert_after (h->pending_head,
578 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
579 "Adding SEND REQUEST for peer `%s' to message queue\n",
580 GNUNET_i2s (&pr->peer));
582 trigger_next_request (h, GNUNET_NO);
587 * The given request hit its timeout. Remove from the
588 * doubly-linked list and call the respective continuation.
590 * @param cls the transmit handle of the request that timed out
591 * @param tc context, can be NULL (!)
594 transmission_timeout (void *cls,
595 const struct GNUNET_SCHEDULER_TaskContext *tc)
597 struct PeerRecord *pr = cls;
598 struct GNUNET_CORE_TransmitHandle *th;
600 pr->timeout_task = GNUNET_SCHEDULER_NO_TASK;
601 th = pr->pending_head;
602 GNUNET_CONTAINER_DLL_remove (pr->pending_head,
607 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
608 "Signalling timeout of request for transmission to CORE service\n");
610 GNUNET_assert (0 == th->get_message (th->get_message_cls, 0, NULL));
611 request_next_transmission (pr);
616 * Transmit the next message to the core service.
619 transmit_message (void *cls,
623 struct GNUNET_CORE_Handle *h = cls;
624 struct ControlMessage *cm;
625 struct GNUNET_CORE_TransmitHandle *th;
626 struct PeerRecord *pr;
627 struct SendMessage *sm;
628 const struct GNUNET_MessageHeader *hdr;
636 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
637 "Transmission failed, initiating reconnect\n");
642 /* first check for control messages */
643 if (NULL != (cm = h->pending_head))
645 hdr = (const struct GNUNET_MessageHeader*) &cm[1];
646 msize = ntohs (hdr->size);
649 trigger_next_request (h, GNUNET_NO);
653 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
654 "Transmitting control message with %u bytes of type %u to core.\n",
655 (unsigned int) msize,
656 (unsigned int) ntohs (hdr->type));
658 memcpy (buf, hdr, msize);
659 GNUNET_CONTAINER_DLL_remove (h->pending_head,
662 if (NULL != cm->cont)
663 GNUNET_SCHEDULER_add_continuation (cm->cont,
665 GNUNET_SCHEDULER_REASON_PREREQ_DONE);
667 trigger_next_request (h, GNUNET_NO);
670 /* now check for 'ready' P2P messages */
671 if (NULL != (pr = h->ready_peer_head))
673 th = pr->pending_head;
674 if (size < th->msize + sizeof (struct SendMessage))
676 trigger_next_request (h, GNUNET_NO);
679 GNUNET_CONTAINER_DLL_remove (h->ready_peer_head,
682 GNUNET_CONTAINER_DLL_remove (pr->pending_head,
686 if (pr->timeout_task != GNUNET_SCHEDULER_NO_TASK)
688 GNUNET_SCHEDULER_cancel (pr->timeout_task);
689 pr->timeout_task = GNUNET_SCHEDULER_NO_TASK;
692 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
693 "Transmitting SEND request to `%s' with %u bytes.\n",
694 GNUNET_i2s (&pr->peer),
695 (unsigned int) th->msize);
697 sm = (struct SendMessage *) buf;
698 sm->header.type = htons (GNUNET_MESSAGE_TYPE_CORE_SEND);
699 sm->priority = htonl (th->priority);
700 sm->deadline = GNUNET_TIME_absolute_hton (th->timeout);
702 ret = th->get_message (th->get_message_cls,
703 size - sizeof (struct SendMessage),
709 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
710 "Size of clients message to peer %s is 0!\n",
711 GNUNET_i2s(&pr->peer));
713 /* client decided to send nothing! */
714 request_next_transmission (pr);
718 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
719 "Produced SEND message to core with %u bytes payload\n",
722 GNUNET_assert (ret >= sizeof (struct GNUNET_MessageHeader));
723 if (ret + sizeof (struct SendMessage) >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
726 request_next_transmission (pr);
729 ret += sizeof (struct SendMessage);
730 sm->header.size = htons (ret);
731 GNUNET_assert (ret <= size);
733 request_next_transmission (pr);
741 * Check the list of pending requests, send the next
744 * @param h core handle
745 * @param ignore_currently_down transmit message even if not initialized?
748 trigger_next_request (struct GNUNET_CORE_Handle *h,
749 int ignore_currently_down)
753 if ( (GNUNET_YES == h->currently_down) &&
754 (ignore_currently_down == GNUNET_NO) )
757 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
758 "Core connection down, not processing queue\n");
765 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
766 "Request pending, not processing queue\n");
770 if (h->pending_head != NULL)
771 msize = ntohs (((struct GNUNET_MessageHeader*) &h->pending_head[1])->size);
772 else if (h->ready_peer_head != NULL)
773 msize = h->ready_peer_head->pending_head->msize + sizeof (struct SendMessage);
777 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
778 "Request queue empty, not processing queue\n");
780 return; /* no pending message */
782 h->cth = GNUNET_CLIENT_notify_transmit_ready (h->client,
784 GNUNET_TIME_UNIT_FOREVER_REL,
786 &transmit_message, h);
791 * Handler for notification messages received from the core.
793 * @param cls our "struct GNUNET_CORE_Handle"
794 * @param msg the message received from the core service
797 main_notify_handler (void *cls,
798 const struct GNUNET_MessageHeader *msg)
800 struct GNUNET_CORE_Handle *h = cls;
801 const struct InitReplyMessage *m;
802 const struct ConnectNotifyMessage *cnm;
803 const struct DisconnectNotifyMessage *dnm;
804 const struct NotifyTrafficMessage *ntm;
805 const struct GNUNET_MessageHeader *em;
806 const struct ConfigurationInfoMessage *cim;
807 const struct PeerStatusNotifyMessage *psnm;
808 const struct SendMessageReady *smr;
809 const struct GNUNET_CORE_MessageHandler *mh;
810 GNUNET_CORE_StartupCallback init;
811 GNUNET_CORE_PeerConfigurationInfoCallback pcic;
812 struct PeerRecord *pr;
813 struct GNUNET_CORE_TransmitHandle *th;
821 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
823 ("Client was disconnected from core service, trying to reconnect.\n"));
827 msize = ntohs (msg->size);
829 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
830 "Processing message of type %u and size %u from core service\n",
831 ntohs (msg->type), msize);
833 switch (ntohs (msg->type))
835 case GNUNET_MESSAGE_TYPE_CORE_INIT_REPLY:
836 if (ntohs (msg->size) != sizeof (struct InitReplyMessage))
842 m = (const struct InitReplyMessage *) msg;
843 GNUNET_break (0 == ntohl (m->reserved));
844 /* start our message processing loop */
845 if (GNUNET_YES == h->currently_down)
847 h->currently_down = GNUNET_NO;
848 trigger_next_request (h, GNUNET_NO);
850 h->retry_backoff = GNUNET_TIME_UNIT_MILLISECONDS;
851 if (NULL != (init = h->init))
853 /* mark so we don't call init on reconnect */
855 GNUNET_CRYPTO_hash (&m->publicKey,
857 GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded),
860 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
861 "Connected to core service of peer `%s'.\n",
862 GNUNET_i2s (&h->me));
864 init (h->cls, h, &h->me, &m->publicKey);
869 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
870 "Successfully reconnected to core service.\n");
874 case GNUNET_MESSAGE_TYPE_CORE_NOTIFY_CONNECT:
875 if (msize != sizeof (struct ConnectNotifyMessage))
881 cnm = (const struct ConnectNotifyMessage *) msg;
883 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
884 "Received notification about connection from `%s'.\n",
885 GNUNET_i2s (&cnm->peer));
887 if (0 == memcmp (&h->me,
889 sizeof (struct GNUNET_PeerIdentity)))
891 /* disconnect from self!? */
895 pr = GNUNET_CONTAINER_multihashmap_get (h->peers,
896 &cnm->peer.hashPubKey);
903 pr = GNUNET_malloc (sizeof (struct PeerRecord));
904 pr->peer = cnm->peer;
906 GNUNET_assert (GNUNET_YES ==
907 GNUNET_CONTAINER_multihashmap_put (h->peers,
908 &cnm->peer.hashPubKey,
910 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_FAST));
911 if (NULL != h->connects)
914 NULL /* FIXME: atsi! */);
916 case GNUNET_MESSAGE_TYPE_CORE_NOTIFY_DISCONNECT:
917 if (msize != sizeof (struct DisconnectNotifyMessage))
923 dnm = (const struct DisconnectNotifyMessage *) msg;
924 if (0 == memcmp (&h->me,
926 sizeof (struct GNUNET_PeerIdentity)))
928 /* connection to self!? */
933 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
934 "Received notification about disconnect from `%s'.\n",
935 GNUNET_i2s (&dnm->peer));
937 pr = GNUNET_CONTAINER_multihashmap_get (h->peers,
938 &dnm->peer.hashPubKey);
945 trigger = ( (pr->prev != NULL) ||
946 (pr->next != NULL) ||
947 (h->ready_peer_head == pr) );
948 disconnect_and_free_peer_entry (h, &dnm->peer.hashPubKey, pr);
950 trigger_next_request (h, GNUNET_NO);
952 case GNUNET_MESSAGE_TYPE_CORE_NOTIFY_STATUS_CHANGE:
953 if (NULL == h->status_events)
958 if (msize != sizeof (struct PeerStatusNotifyMessage))
964 psnm = (const struct PeerStatusNotifyMessage *) msg;
965 if (0 == memcmp (&h->me,
967 sizeof (struct GNUNET_PeerIdentity)))
974 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
975 "Received notification about status change by `%s'.\n",
976 GNUNET_i2s (&psnm->peer));
978 pr = GNUNET_CONTAINER_multihashmap_get (h->peers,
979 &psnm->peer.hashPubKey);
986 h->status_events (h->cls,
990 GNUNET_TIME_absolute_ntoh (psnm->timeout),
991 NULL /* FIXME: atsi */);
993 case GNUNET_MESSAGE_TYPE_CORE_NOTIFY_INBOUND:
995 sizeof (struct NotifyTrafficMessage) +
996 sizeof (struct GNUNET_MessageHeader))
1002 ntm = (const struct NotifyTrafficMessage *) msg;
1003 if (0 == memcmp (&h->me,
1005 sizeof (struct GNUNET_PeerIdentity)))
1011 em = (const struct GNUNET_MessageHeader *) &ntm[1];
1013 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1014 "Received message of type %u and size %u from peer `%4s'\n",
1017 GNUNET_i2s (&ntm->peer));
1019 pr = GNUNET_CONTAINER_multihashmap_get (h->peers,
1020 &ntm->peer.hashPubKey);
1024 reconnect_later (h);
1027 if ((GNUNET_NO == h->inbound_hdr_only) &&
1028 (msize != ntohs (em->size) + sizeof (struct NotifyTrafficMessage)))
1031 reconnect_later (h);
1034 et = ntohs (em->type);
1035 for (hpos = 0; hpos < h->hcnt; hpos++)
1037 mh = &h->handlers[hpos];
1040 if ((mh->expected_size != ntohs (em->size)) &&
1041 (mh->expected_size != 0))
1047 h->handlers[hpos].callback (h->cls, &ntm->peer, em,
1048 NULL /* FIXME: atsi */))
1050 /* error in processing, do not process other messages! */
1054 if (NULL != h->inbound_notify)
1055 h->inbound_notify (h->cls, &ntm->peer, em,
1056 NULL /* FIXME: atsi */);
1058 case GNUNET_MESSAGE_TYPE_CORE_NOTIFY_OUTBOUND:
1060 sizeof (struct NotifyTrafficMessage) +
1061 sizeof (struct GNUNET_MessageHeader))
1064 reconnect_later (h);
1067 ntm = (const struct NotifyTrafficMessage *) msg;
1068 if (0 == memcmp (&h->me,
1070 sizeof (struct GNUNET_PeerIdentity)))
1076 em = (const struct GNUNET_MessageHeader *) &ntm[1];
1077 pr = GNUNET_CONTAINER_multihashmap_get (h->peers,
1078 &ntm->peer.hashPubKey);
1082 reconnect_later (h);
1086 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1087 "Received notification about transmission to `%s'.\n",
1088 GNUNET_i2s (&ntm->peer));
1090 if ((GNUNET_NO == h->outbound_hdr_only) &&
1091 (msize != ntohs (em->size) + sizeof (struct NotifyTrafficMessage)))
1094 reconnect_later (h);
1097 if (NULL == h->outbound_notify)
1102 h->outbound_notify (h->cls, &ntm->peer, em,
1103 NULL /* FIXME: atsi? */);
1105 case GNUNET_MESSAGE_TYPE_CORE_SEND_READY:
1106 if (msize != sizeof (struct SendMessageReady))
1109 reconnect_later (h);
1112 smr = (const struct SendMessageReady *) msg;
1113 if (0 == memcmp (&h->me,
1115 sizeof (struct GNUNET_PeerIdentity)))
1121 pr = GNUNET_CONTAINER_multihashmap_get (h->peers,
1122 &smr->peer.hashPubKey);
1126 reconnect_later (h);
1130 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1131 "Received notification about transmission readiness to `%s'.\n",
1132 GNUNET_i2s (&smr->peer));
1134 th = pr->pending_head;
1135 if (ntohs (smr->smr_id) != th->smr_id)
1137 /* READY message is for expired or cancelled message,
1138 ignore! (we should have already sent another request) */
1141 if ( (pr->prev != NULL) ||
1142 (pr->next != NULL) ||
1143 (h->ready_peer_head == pr) )
1145 /* we should not already be on the ready list... */
1147 reconnect_later (h);
1150 GNUNET_CONTAINER_DLL_insert (h->ready_peer_head,
1153 trigger_next_request (h, GNUNET_NO);
1155 case GNUNET_MESSAGE_TYPE_CORE_CONFIGURATION_INFO:
1156 if (ntohs (msg->size) != sizeof (struct ConfigurationInfoMessage))
1159 reconnect_later (h);
1162 cim = (const struct ConfigurationInfoMessage*) msg;
1163 if (0 == memcmp (&h->me,
1165 sizeof (struct GNUNET_PeerIdentity)))
1172 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1173 "Received notification about configuration update for `%s'.\n",
1174 GNUNET_i2s (&cim->peer));
1176 pr = GNUNET_CONTAINER_multihashmap_get (h->peers,
1177 &cim->peer.hashPubKey);
1181 reconnect_later (h);
1184 if (pr->rim_id != ntohl (cim->rim_id))
1192 ntohl (cim->reserved_amount),
1193 GNUNET_ntohll (cim->preference));
1196 reconnect_later (h);
1199 GNUNET_CLIENT_receive (h->client,
1200 &main_notify_handler, h,
1201 GNUNET_TIME_UNIT_FOREVER_REL);
1206 * Task executed once we are done transmitting the INIT message.
1207 * Starts our 'receive' loop.
1209 * @param cls the 'struct GNUNET_CORE_Handle'
1210 * @param tc task context
1213 init_done_task (void *cls,
1214 const struct GNUNET_SCHEDULER_TaskContext *tc)
1216 struct GNUNET_CORE_Handle *h = cls;
1220 if (0 == (tc->reason & GNUNET_SCHEDULER_REASON_PREREQ_DONE))
1223 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1224 "Failed to exchange INIT with core, retrying\n");
1226 reconnect_later (h);
1229 GNUNET_CLIENT_receive (h->client,
1230 &main_notify_handler,
1232 GNUNET_TIME_UNIT_FOREVER_REL);
1237 * Our current client connection went down. Clean it up
1238 * and try to reconnect!
1240 * @param h our handle to the core service
1243 reconnect (struct GNUNET_CORE_Handle *h)
1245 struct ControlMessage *cm;
1246 struct InitMessage *init;
1253 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1254 "Reconnecting to CORE service\n");
1256 GNUNET_assert (h->client == NULL);
1257 GNUNET_assert (h->currently_down == GNUNET_YES);
1258 h->client = GNUNET_CLIENT_connect ("core", h->cfg);
1259 if (h->client == NULL)
1261 reconnect_later (h);
1264 msize = h->hcnt * sizeof (uint16_t) + sizeof (struct InitMessage);
1265 cm = GNUNET_malloc (sizeof (struct ControlMessage) +
1267 cm->cont = &init_done_task;
1269 init = (struct InitMessage*) &cm[1];
1270 init->header.type = htons (GNUNET_MESSAGE_TYPE_CORE_INIT);
1271 init->header.size = htons (msize);
1272 opt = GNUNET_CORE_OPTION_SEND_CONNECT | GNUNET_CORE_OPTION_SEND_DISCONNECT;
1273 if (h->status_events != NULL)
1274 opt |= GNUNET_CORE_OPTION_SEND_STATUS_CHANGE;
1275 if (h->inbound_notify != NULL)
1277 if (h->inbound_hdr_only)
1278 opt |= GNUNET_CORE_OPTION_SEND_HDR_INBOUND;
1280 opt |= GNUNET_CORE_OPTION_SEND_FULL_INBOUND;
1282 if (h->outbound_notify != NULL)
1284 if (h->outbound_hdr_only)
1285 opt |= GNUNET_CORE_OPTION_SEND_HDR_OUTBOUND;
1287 opt |= GNUNET_CORE_OPTION_SEND_FULL_OUTBOUND;
1289 init->options = htonl (opt);
1290 ts = (uint16_t *) &init[1];
1291 for (hpos = 0; hpos < h->hcnt; hpos++)
1292 ts[hpos] = htons (h->handlers[hpos].type);
1293 GNUNET_CONTAINER_DLL_insert (h->pending_head,
1296 trigger_next_request (h, GNUNET_YES);
1302 * Connect to the core service. Note that the connection may
1303 * complete (or fail) asynchronously.
1305 * @param cfg configuration to use
1306 * @param queue_size size of the per-peer message queue
1307 * @param cls closure for the various callbacks that follow (including handlers in the handlers array)
1308 * @param init callback to call on timeout or once we have successfully
1309 * connected to the core service; note that timeout is only meaningful if init is not NULL
1310 * @param connects function to call on peer connect, can be NULL
1311 * @param disconnects function to call on peer disconnect / timeout, can be NULL
1312 * @param status_events function to call on changes to peer connection status, can be NULL
1313 * @param inbound_notify function to call for all inbound messages, can be NULL
1314 * @param inbound_hdr_only set to GNUNET_YES if inbound_notify will only read the
1315 * GNUNET_MessageHeader and hence we do not need to give it the full message;
1316 * can be used to improve efficiency, ignored if inbound_notify is NULLL
1317 * @param outbound_notify function to call for all outbound messages, can be NULL
1318 * @param outbound_hdr_only set to GNUNET_YES if outbound_notify will only read the
1319 * GNUNET_MessageHeader and hence we do not need to give it the full message
1320 * can be used to improve efficiency, ignored if outbound_notify is NULLL
1321 * @param handlers callbacks for messages we care about, NULL-terminated
1322 * @return handle to the core service (only useful for disconnect until 'init' is called);
1323 * NULL on error (in this case, init is never called)
1325 struct GNUNET_CORE_Handle *
1326 GNUNET_CORE_connect (const struct GNUNET_CONFIGURATION_Handle *cfg,
1327 unsigned int queue_size,
1329 GNUNET_CORE_StartupCallback init,
1330 GNUNET_CORE_ConnectEventHandler connects,
1331 GNUNET_CORE_DisconnectEventHandler disconnects,
1332 GNUNET_CORE_PeerStatusEventHandler status_events,
1333 GNUNET_CORE_MessageCallback inbound_notify,
1334 int inbound_hdr_only,
1335 GNUNET_CORE_MessageCallback outbound_notify,
1336 int outbound_hdr_only,
1337 const struct GNUNET_CORE_MessageHandler *handlers)
1339 struct GNUNET_CORE_Handle *h;
1341 h = GNUNET_malloc (sizeof (struct GNUNET_CORE_Handle));
1343 h->queue_size = queue_size;
1346 h->connects = connects;
1347 h->disconnects = disconnects;
1348 h->status_events = status_events;
1349 h->inbound_notify = inbound_notify;
1350 h->outbound_notify = outbound_notify;
1351 h->inbound_hdr_only = inbound_hdr_only;
1352 h->outbound_hdr_only = outbound_hdr_only;
1353 h->handlers = handlers;
1355 h->currently_down = GNUNET_YES;
1356 h->peers = GNUNET_CONTAINER_multihashmap_create (128);
1357 h->retry_backoff = GNUNET_TIME_UNIT_MILLISECONDS;
1358 while (handlers[h->hcnt].callback != NULL)
1360 GNUNET_assert (h->hcnt <
1361 (GNUNET_SERVER_MAX_MESSAGE_SIZE -
1362 sizeof (struct InitMessage)) / sizeof (uint16_t));
1364 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1365 "Connecting to CORE service\n");
1373 * Disconnect from the core service. This function can only
1374 * be called *after* all pending 'GNUNET_CORE_notify_transmit_ready'
1375 * requests have been explicitly cancelled.
1377 * @param handle connection to core to disconnect
1380 GNUNET_CORE_disconnect (struct GNUNET_CORE_Handle *handle)
1382 struct ControlMessage *cm;
1385 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1386 "Disconnecting from CORE service\n");
1388 if (handle->cth != NULL)
1390 GNUNET_CLIENT_notify_transmit_ready_cancel (handle->cth);
1393 if (handle->client != NULL)
1395 GNUNET_CLIENT_disconnect (handle->client, GNUNET_NO);
1396 handle->client = NULL;
1398 if (handle->reconnect_task != GNUNET_SCHEDULER_NO_TASK)
1400 GNUNET_SCHEDULER_cancel (handle->reconnect_task);
1401 handle->reconnect_task = GNUNET_SCHEDULER_NO_TASK;
1403 while (NULL != (cm = handle->pending_head))
1405 GNUNET_CONTAINER_DLL_remove (handle->pending_head,
1406 handle->pending_tail,
1408 cm->cont (cm->cont_cls, NULL);
1411 GNUNET_CONTAINER_multihashmap_iterate (handle->peers,
1412 &disconnect_and_free_peer_entry,
1414 GNUNET_CONTAINER_multihashmap_destroy (handle->peers);
1415 GNUNET_break (handle->ready_peer_head == NULL);
1416 GNUNET_free (handle);
1421 * Ask the core to call "notify" once it is ready to transmit the
1422 * given number of bytes to the specified "target". If we are not yet
1423 * connected to the specified peer, a call to this function will cause
1424 * us to try to establish a connection.
1426 * @param handle connection to core service
1427 * @param priority how important is the message?
1428 * @param maxdelay how long can the message wait?
1429 * @param target who should receive the message,
1430 * use NULL for this peer (loopback)
1431 * @param notify_size how many bytes of buffer space does notify want?
1432 * @param notify function to call when buffer space is available
1433 * @param notify_cls closure for notify
1434 * @return non-NULL if the notify callback was queued,
1435 * NULL if we can not even queue the request (insufficient
1436 * memory); if NULL is returned, "notify" will NOT be called.
1438 struct GNUNET_CORE_TransmitHandle *
1439 GNUNET_CORE_notify_transmit_ready (struct GNUNET_CORE_Handle *handle,
1441 struct GNUNET_TIME_Relative maxdelay,
1442 const struct GNUNET_PeerIdentity *target,
1444 GNUNET_CONNECTION_TransmitReadyNotify notify,
1447 struct PeerRecord *pr;
1448 struct GNUNET_CORE_TransmitHandle *th;
1449 struct GNUNET_CORE_TransmitHandle *pos;
1450 struct GNUNET_CORE_TransmitHandle *prev;
1451 struct GNUNET_CORE_TransmitHandle *minp;
1453 pr = GNUNET_CONTAINER_multihashmap_get (handle->peers,
1454 &target->hashPubKey);
1457 /* attempt to send to peer that is not connected */
1458 GNUNET_log(GNUNET_ERROR_TYPE_WARNING,
1459 "Attempting to send to peer `%s' from peer `%s', but not connected!\n",
1460 GNUNET_i2s(target), GNUNET_h2s(&handle->me.hashPubKey));
1464 GNUNET_assert (notify_size + sizeof (struct SendMessage) <
1465 GNUNET_SERVER_MAX_MESSAGE_SIZE);
1466 th = GNUNET_malloc (sizeof (struct GNUNET_CORE_TransmitHandle));
1468 th->get_message = notify;
1469 th->get_message_cls = notify_cls;
1470 th->timeout = GNUNET_TIME_relative_to_absolute (maxdelay);
1471 th->priority = priority;
1472 th->msize = notify_size;
1473 /* bound queue size */
1474 if (pr->queue_size == handle->queue_size)
1476 /* find lowest-priority entry */
1477 minp = pr->pending_head;
1479 while (prev != NULL)
1481 if (prev->priority < minp->priority)
1487 GNUNET_break (handle->queue_size != 0);
1488 GNUNET_break (pr->queue_size == 0);
1491 if (priority <= minp->priority)
1494 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1495 "Dropping transmission request: priority too low\n");
1497 return NULL; /* priority too low */
1499 GNUNET_CONTAINER_DLL_remove (pr->pending_head,
1504 minp->get_message (minp->get_message_cls,
1509 /* Order entries by deadline, but SKIP 'HEAD' if
1510 we're in the 'ready_peer_*' DLL */
1511 pos = pr->pending_head;
1512 if ( (pr->prev != NULL) ||
1513 (pr->next != NULL) ||
1514 (pr == handle->ready_peer_head) )
1516 GNUNET_assert (pos != NULL);
1517 pos = pos->next; /* skip head */
1520 /* insertion sort */
1522 while ( (pos != NULL) &&
1523 (pos->timeout.abs_value < th->timeout.abs_value) )
1528 GNUNET_CONTAINER_DLL_insert_after (pr->pending_head,
1533 /* was the request queue previously empty? */
1535 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1536 "Transmission request added to queue\n");
1538 if (pr->pending_head == th)
1539 request_next_transmission (pr);
1545 * Cancel the specified transmission-ready notification.
1547 * @param th handle that was returned by "notify_transmit_ready".
1550 GNUNET_CORE_notify_transmit_ready_cancel (struct GNUNET_CORE_TransmitHandle
1553 struct PeerRecord *pr = th->peer;
1554 struct GNUNET_CORE_Handle *h = pr->ch;
1557 was_head = (pr->pending_head == th);
1558 GNUNET_CONTAINER_DLL_remove (pr->pending_head,
1564 /* we're currently in the control queue, remove */
1565 GNUNET_CONTAINER_DLL_remove (h->pending_head,
1568 GNUNET_free (th->cm);
1573 if ( (pr->prev != NULL) ||
1574 (pr->next != NULL) ||
1575 (pr == h->ready_peer_head) )
1577 /* the request that was 'approved' by core was
1578 cancelled before it could be transmitted; remove
1579 us from the 'ready' list */
1580 GNUNET_CONTAINER_DLL_remove (h->ready_peer_head,
1584 request_next_transmission (pr);
1589 /* ****************** GNUNET_CORE_peer_request_connect ******************** */
1592 * Handle for a request to the core to connect to
1593 * a particular peer. Can be used to cancel the request
1594 * (before the 'cont'inuation is called).
1596 struct GNUNET_CORE_PeerRequestHandle
1600 * Link to control message.
1602 struct ControlMessage *cm;
1607 struct GNUNET_CORE_Handle *h;
1610 * Continuation to run when done.
1612 GNUNET_SCHEDULER_Task cont;
1615 * Closure for 'cont'.
1623 * Continuation called when the control message was transmitted.
1624 * Calls the original continuation and frees the remaining
1627 * @param cls the 'struct GNUNET_CORE_PeerRequestHandle'
1628 * @param tc scheduler context
1631 peer_request_connect_cont (void *cls,
1632 const struct GNUNET_SCHEDULER_TaskContext *tc)
1634 struct GNUNET_CORE_PeerRequestHandle *ret = cls;
1636 if (ret->cont != NULL)
1639 GNUNET_SCHEDULER_add_now (ret->cont,
1642 ret->cont (ret->cont_cls, tc);
1649 * Request that the core should try to connect to a particular peer.
1650 * Once the request has been transmitted to the core, the continuation
1651 * function will be called. Note that this does NOT mean that a
1652 * connection was successfully established -- it only means that the
1653 * core will now try. Successful establishment of the connection
1654 * will be signalled to the 'connects' callback argument of
1655 * 'GNUNET_CORE_connect' only. If the core service does not respond
1656 * to our connection attempt within the given time frame, 'cont' will
1657 * be called with the TIMEOUT reason code.
1659 * @param h core handle
1660 * @param timeout how long to try to talk to core
1661 * @param peer who should we connect to
1662 * @param cont function to call once the request has been completed (or timed out)
1663 * @param cont_cls closure for cont
1664 * @return NULL on error (cont will not be called), otherwise handle for cancellation
1666 struct GNUNET_CORE_PeerRequestHandle *
1667 GNUNET_CORE_peer_request_connect (struct GNUNET_CORE_Handle *h,
1668 struct GNUNET_TIME_Relative timeout,
1669 const struct GNUNET_PeerIdentity * peer,
1670 GNUNET_SCHEDULER_Task cont,
1673 struct GNUNET_CORE_PeerRequestHandle *ret;
1674 struct ControlMessage *cm;
1675 struct ConnectMessage *msg;
1677 cm = GNUNET_malloc (sizeof (struct ControlMessage) +
1678 sizeof (struct ConnectMessage));
1679 msg = (struct ConnectMessage*) &cm[1];
1680 msg->header.type = htons (GNUNET_MESSAGE_TYPE_CORE_REQUEST_CONNECT);
1681 msg->header.size = htons (sizeof (struct ConnectMessage));
1682 msg->reserved = htonl (0);
1683 msg->timeout = GNUNET_TIME_relative_hton (timeout);
1685 GNUNET_CONTAINER_DLL_insert (h->pending_head,
1688 ret = GNUNET_malloc (sizeof (struct GNUNET_CORE_PeerRequestHandle));
1692 ret->cont_cls = cont_cls;
1693 cm->cont = &peer_request_connect_cont;
1696 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1697 "Queueing REQUEST_CONNECT request\n");
1699 if (h->pending_head == cm)
1700 trigger_next_request (h, GNUNET_NO);
1706 * Cancel a pending request to connect to a particular peer. Must not
1707 * be called after the 'cont' function was invoked.
1709 * @param req request handle that was returned for the original request
1712 GNUNET_CORE_peer_request_connect_cancel (struct GNUNET_CORE_PeerRequestHandle *req)
1714 struct GNUNET_CORE_Handle *h = req->h;
1715 struct ControlMessage *cm = req->cm;
1717 GNUNET_CONTAINER_DLL_remove (h->pending_head,
1725 /* ****************** GNUNET_CORE_peer_change_preference ******************** */
1728 struct GNUNET_CORE_InformationRequestContext
1732 * Our connection to the service.
1734 struct GNUNET_CORE_Handle *h;
1737 * Function to call with the information.
1739 GNUNET_CORE_PeerConfigurationInfoCallback info;
1747 * Link to control message, NULL if CM was sent.
1749 struct ControlMessage *cm;
1752 * Link to peer record.
1754 struct PeerRecord *pr;
1759 * CM was sent, remove link so we don't double-free.
1761 * @param cls the 'struct GNUNET_CORE_InformationRequestContext'
1762 * @param tc scheduler context
1765 change_preference_send_continuation (void *cls,
1766 const struct GNUNET_SCHEDULER_TaskContext *tc)
1768 struct GNUNET_CORE_InformationRequestContext *irc = cls;
1775 * Obtain statistics and/or change preferences for the given peer.
1777 * @param h core handle
1778 * @param peer identifies the peer
1779 * @param timeout after how long should we give up (and call "info" with NULL
1780 * for "peer" to signal an error)?
1781 * @param bw_out set to the current bandwidth limit (sending) for this peer,
1782 * caller should set "bw_out" to "-1" to avoid changing
1783 * the current value; otherwise "bw_out" will be lowered to
1784 * the specified value; passing a pointer to "0" can be used to force
1785 * us to disconnect from the peer; "bw_out" might not increase
1786 * as specified since the upper bound is generally
1787 * determined by the other peer!
1788 * @param amount reserve N bytes for receiving, negative
1789 * amounts can be used to undo a (recent) reservation;
1790 * @param preference increase incoming traffic share preference by this amount;
1791 * in the absence of "amount" reservations, we use this
1792 * preference value to assign proportional bandwidth shares
1793 * to all connected peers
1794 * @param info function to call with the resulting configuration information
1795 * @param info_cls closure for info
1796 * @return NULL on error
1798 struct GNUNET_CORE_InformationRequestContext *
1799 GNUNET_CORE_peer_change_preference (struct GNUNET_CORE_Handle *h,
1800 const struct GNUNET_PeerIdentity *peer,
1801 struct GNUNET_TIME_Relative timeout,
1802 struct GNUNET_BANDWIDTH_Value32NBO bw_out,
1804 uint64_t preference,
1805 GNUNET_CORE_PeerConfigurationInfoCallback info,
1808 struct GNUNET_CORE_InformationRequestContext *irc;
1809 struct PeerRecord *pr;
1810 struct RequestInfoMessage *rim;
1811 struct ControlMessage *cm;
1813 pr = GNUNET_CONTAINER_multihashmap_get (h->peers,
1817 /* attempt to change preference on peer that is not connected */
1821 if (pr->pcic != NULL)
1823 /* second change before first one is done */
1827 irc = GNUNET_malloc (sizeof (struct GNUNET_CORE_InformationRequestContext));
1831 irc->info_cls = info_cls;
1832 cm = GNUNET_malloc (sizeof (struct ControlMessage) +
1833 sizeof (struct RequestInfoMessage));
1834 cm->cont = &change_preference_send_continuation;
1837 rim = (struct RequestInfoMessage*) &cm[1];
1838 rim->header.size = htons (sizeof (struct RequestInfoMessage));
1839 rim->header.type = htons (GNUNET_MESSAGE_TYPE_CORE_REQUEST_INFO);
1840 rim->rim_id = htonl (pr->rim_id = h->rim_id_gen++);
1841 rim->limit_outbound = bw_out;
1842 rim->reserve_inbound = htonl (amount);
1843 rim->preference_change = GNUNET_htonll(preference);
1846 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1847 "Queueing CHANGE PREFERENCE request\n");
1849 GNUNET_CONTAINER_DLL_insert (h->pending_head,
1853 pr->pcic_cls = info_cls;
1854 if (h->pending_head == cm)
1855 trigger_next_request (h, GNUNET_NO);
1861 * Cancel request for getting information about a peer.
1862 * Note that an eventual change in preference, trust or bandwidth
1863 * assignment MAY have already been committed at the time,
1864 * so cancelling a request is NOT sure to undo the original
1865 * request. The original request may or may not still commit.
1866 * The only thing cancellation ensures is that the callback
1867 * from the original request will no longer be called.
1869 * @param irc context returned by the original GNUNET_CORE_peer_get_info call
1872 GNUNET_CORE_peer_change_preference_cancel (struct GNUNET_CORE_InformationRequestContext *irc)
1874 struct GNUNET_CORE_Handle *h = irc->h;
1875 struct PeerRecord *pr = irc->pr;
1877 if (irc->cm != NULL)
1879 GNUNET_CONTAINER_DLL_remove (h->pending_head,
1882 GNUNET_free (irc->cm);
1885 pr->pcic_cls = NULL;
1891 /* ********************* GNUNET_CORE_iterate_peers *********************** */
1894 * Context for 'iterate_peers' helper function.
1896 struct IterationContext
1901 GNUNET_CORE_ConnectEventHandler peer_cb;
1904 * Closure for 'peer_cb'.
1911 * Call callback for each peer.
1913 * @param cls the 'struct IterationContext'
1914 * @param hc peer identity, not used
1915 * @param value the 'struct PeerRecord'
1916 * @return GNUNET_YES (continue iteration)
1919 iterate_peers (void *cls,
1920 const GNUNET_HashCode *hc,
1923 struct IterationContext *ic = cls;
1924 struct PeerRecord *pr = value;
1926 ic->peer_cb (ic->cb_cls,
1928 NULL /* FIXME: pass atsi? */);
1934 * Obtain statistics and/or change preferences for the given peer.
1936 * @param h handle to core
1937 * @param peer_cb function to call with the peer information
1938 * @param cb_cls closure for peer_cb
1939 * @return GNUNET_OK if iterating, GNUNET_SYSERR on error
1942 GNUNET_CORE_iterate_peers (struct GNUNET_CORE_Handle *h,
1943 GNUNET_CORE_ConnectEventHandler peer_cb,
1946 struct IterationContext ic;
1948 ic.peer_cb = peer_cb;
1950 GNUNET_CONTAINER_multihashmap_iterate (h->peers,
1957 /* end of core_api.c */