2 This file is part of GNUnet.
3 Copyright (C) 2012-2014 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., 51 Franklin Street, Fifth Floor,
18 Boston, MA 02110-1301, USA.
22 * @brief api for the set service
23 * @author Florian Dold
24 * @author Christian Grothoff
27 #include "gnunet_util_lib.h"
28 #include "gnunet_protocols.h"
29 #include "gnunet_client_lib.h"
30 #include "gnunet_set_service.h"
34 #define LOG(kind,...) GNUNET_log_from (kind, "set-api",__VA_ARGS__)
38 struct SetCopyRequest *next;
40 struct SetCopyRequest *prev;
44 GNUNET_SET_CopyReadyCallback cb;
48 * Opaque handle to a set.
50 struct GNUNET_SET_Handle
53 * Client connected to the set service.
55 struct GNUNET_CLIENT_Connection *client;
58 * Message queue for @e client.
60 struct GNUNET_MQ_Handle *mq;
63 * Linked list of operations on the set.
65 struct GNUNET_SET_OperationHandle *ops_head;
68 * Linked list of operations on the set.
70 struct GNUNET_SET_OperationHandle *ops_tail;
73 * Callback for the current iteration over the set,
74 * NULL if no iterator is active.
76 GNUNET_SET_ElementIterator iterator;
79 * Closure for @e iterator
84 * Should the set be destroyed once all operations are gone?
86 int destroy_requested;
89 * Has the set become invalid (e.g. service died)?
94 * Both client and service count the number of iterators
95 * created so far to match replies with iterators.
97 uint16_t iteration_id;
100 * Configuration, needed when creating (lazy) copies.
102 const struct GNUNET_CONFIGURATION_Handle *cfg;
105 * Doubly linked list of copy requests.
107 struct SetCopyRequest *copy_req_head;
110 * Doubly linked list of copy requests.
112 struct SetCopyRequest *copy_req_tail;
117 * Handle for a set operation request from another peer.
119 struct GNUNET_SET_Request
122 * Id of the request, used to identify the request when
123 * accepting/rejecting it.
128 * Has the request been accepted already?
129 * #GNUNET_YES/#GNUNET_NO
136 * Handle to an operation. Only known to the service after committing
137 * the handle with a set.
139 struct GNUNET_SET_OperationHandle
142 * Function to be called when we have a result,
145 GNUNET_SET_ResultIterator result_cb;
148 * Closure for @e result_cb.
153 * Local set used for the operation,
154 * NULL if no set has been provided by conclude yet.
156 struct GNUNET_SET_Handle *set;
159 * Message sent to the server on calling conclude,
160 * NULL if conclude has been called.
162 struct GNUNET_MQ_Envelope *conclude_mqm;
165 * Address of the request if in the conclude message,
166 * used to patch the request id into the message when the set is known.
168 uint32_t *request_id_addr;
171 * Handles are kept in a linked list.
173 struct GNUNET_SET_OperationHandle *prev;
176 * Handles are kept in a linked list.
178 struct GNUNET_SET_OperationHandle *next;
181 * Request ID to identify the operation within the set.
188 * Opaque handle to a listen operation.
190 struct GNUNET_SET_ListenHandle
193 * Connection to the service.
195 struct GNUNET_CLIENT_Connection *client;
198 * Message queue for the client.
200 struct GNUNET_MQ_Handle* mq;
203 * Configuration handle for the listener, stored
204 * here to be able to reconnect transparently on
205 * connection failure.
207 const struct GNUNET_CONFIGURATION_Handle *cfg;
210 * Function to call on a new incoming request,
213 GNUNET_SET_ListenCallback listen_cb;
216 * Closure for @e listen_cb.
221 * Application ID we listen for.
223 struct GNUNET_HashCode app_id;
226 * Time to wait until we try to reconnect on failure.
228 struct GNUNET_TIME_Relative reconnect_backoff;
231 * Task for reconnecting when the listener fails.
233 struct GNUNET_SCHEDULER_Task * reconnect_task;
236 * Operation we listen for.
238 enum GNUNET_SET_OperationType operation;
242 /* mutual recursion with handle_copy_lazy */
243 static struct GNUNET_SET_Handle *
244 create_internal (const struct GNUNET_CONFIGURATION_Handle *cfg,
245 enum GNUNET_SET_OperationType op,
250 * Handle element for iteration over the set. Notifies the
251 * iterator and sends an acknowledgement to the service.
253 * @param cls the `struct GNUNET_SET_Handle *`
254 * @param mh the message
257 handle_copy_lazy (void *cls,
258 const struct GNUNET_MessageHeader *mh)
260 struct GNUNET_SET_CopyLazyResponseMessage *msg;
261 struct GNUNET_SET_Handle *set = cls;
262 struct SetCopyRequest *req;
263 struct GNUNET_SET_Handle *new_set;
265 msg = (struct GNUNET_SET_CopyLazyResponseMessage *) mh;
267 req = set->copy_req_head;
271 /* Service sent us unsolicited lazy copy response */
276 GNUNET_CONTAINER_DLL_remove (set->copy_req_head,
281 // We pass none as operation here, since it doesn't matter when
283 new_set = create_internal (set->cfg, GNUNET_SET_OPERATION_NONE, &msg->cookie);
285 req->cb (req->cls, new_set);
292 * Handle element for iteration over the set. Notifies the
293 * iterator and sends an acknowledgement to the service.
295 * @param cls the `struct GNUNET_SET_Handle *`
296 * @param mh the message
299 handle_iter_element (void *cls,
300 const struct GNUNET_MessageHeader *mh)
302 struct GNUNET_SET_Handle *set = cls;
303 GNUNET_SET_ElementIterator iter = set->iterator;
304 struct GNUNET_SET_Element element;
305 const struct GNUNET_SET_IterResponseMessage *msg;
306 struct GNUNET_SET_IterAckMessage *ack_msg;
307 struct GNUNET_MQ_Envelope *ev;
310 msize = ntohs (mh->size);
311 if (msize < sizeof (sizeof (struct GNUNET_SET_IterResponseMessage)))
313 /* message malformed */
315 set->iterator = NULL;
317 iter (set->iterator_cls,
321 msg = (const struct GNUNET_SET_IterResponseMessage *) mh;
322 if (set->iteration_id != ntohs (msg->iteration_id))
324 /* element from a previous iteration, skip! */
329 element.size = msize - sizeof (struct GNUNET_SET_IterResponseMessage);
330 element.element_type = htons (msg->element_type);
331 element.data = &msg[1];
332 iter (set->iterator_cls,
335 ev = GNUNET_MQ_msg (ack_msg,
336 GNUNET_MESSAGE_TYPE_SET_ITER_ACK);
337 ack_msg->send_more = htonl ((NULL != iter));
338 GNUNET_MQ_send (set->mq, ev);
343 * Handle message signalling conclusion of iteration over the set.
344 * Notifies the iterator that we are done.
347 * @param mh the message
350 handle_iter_done (void *cls,
351 const struct GNUNET_MessageHeader *mh)
353 struct GNUNET_SET_Handle *set = cls;
354 GNUNET_SET_ElementIterator iter = set->iterator;
358 set->iterator = NULL;
360 iter (set->iterator_cls,
366 * Handle result message for a set operation.
369 * @param mh the message
372 handle_result (void *cls,
373 const struct GNUNET_MessageHeader *mh)
375 struct GNUNET_SET_Handle *set = cls;
376 const struct GNUNET_SET_ResultMessage *msg;
377 struct GNUNET_SET_OperationHandle *oh;
378 struct GNUNET_SET_Element e;
379 enum GNUNET_SET_Status result_status;
381 msg = (const struct GNUNET_SET_ResultMessage *) mh;
382 GNUNET_assert (NULL != set->mq);
383 result_status = ntohs (msg->result_status);
384 LOG (GNUNET_ERROR_TYPE_DEBUG,
385 "Got result message with status %d\n",
388 oh = GNUNET_MQ_assoc_get (set->mq,
389 ntohl (msg->request_id));
392 /* 'oh' can be NULL if we canceled the operation, but the service
393 did not get the cancel message yet. */
394 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
395 "Ignoring result from canceled operation\n");
398 if (GNUNET_SET_STATUS_OK != result_status)
400 /* status is not #GNUNET_SET_STATUS_OK => there's no attached element,
401 * and this is the last result message we get */
402 GNUNET_MQ_assoc_remove (set->mq,
403 ntohl (msg->request_id));
404 GNUNET_CONTAINER_DLL_remove (set->ops_head,
407 if ( (GNUNET_YES == set->destroy_requested) &&
408 (NULL == set->ops_head) )
409 GNUNET_SET_destroy (set);
410 if (NULL != oh->result_cb)
411 oh->result_cb (oh->result_cls,
414 switch (result_status)
416 case GNUNET_SET_STATUS_OK:
418 case GNUNET_SET_STATUS_FAILURE:
419 oh->result_cb = NULL;
421 case GNUNET_SET_STATUS_HALF_DONE:
423 case GNUNET_SET_STATUS_DONE:
424 oh->result_cb = NULL;
431 e.size = ntohs (mh->size) - sizeof (struct GNUNET_SET_ResultMessage);
432 e.element_type = msg->element_type;
433 if (NULL != oh->result_cb)
434 oh->result_cb (oh->result_cls,
441 * Destroy the given set operation.
443 * @param oh set operation to destroy
446 set_operation_destroy (struct GNUNET_SET_OperationHandle *oh)
448 struct GNUNET_SET_Handle *set = oh->set;
449 struct GNUNET_SET_OperationHandle *h_assoc;
451 if (NULL != oh->conclude_mqm)
452 GNUNET_MQ_discard (oh->conclude_mqm);
453 /* is the operation already commited? */
456 GNUNET_CONTAINER_DLL_remove (set->ops_head,
459 h_assoc = GNUNET_MQ_assoc_remove (set->mq,
461 GNUNET_assert ((NULL == h_assoc) || (h_assoc == oh));
468 * Cancel the given set operation. We need to send an explicit cancel
469 * message, as all operations one one set communicate using one
472 * @param oh set operation to cancel
475 GNUNET_SET_operation_cancel (struct GNUNET_SET_OperationHandle *oh)
477 struct GNUNET_SET_Handle *set = oh->set;
478 struct GNUNET_SET_CancelMessage *m;
479 struct GNUNET_MQ_Envelope *mqm;
483 mqm = GNUNET_MQ_msg (m, GNUNET_MESSAGE_TYPE_SET_CANCEL);
484 m->request_id = htonl (oh->request_id);
485 GNUNET_MQ_send (set->mq, mqm);
487 set_operation_destroy (oh);
488 if ( (NULL != set) &&
489 (GNUNET_YES == set->destroy_requested) &&
490 (NULL == set->ops_head) )
492 LOG (GNUNET_ERROR_TYPE_DEBUG,
493 "Destroying set after operation cancel\n");
494 GNUNET_SET_destroy (set);
500 * We encountered an error communicating with the set service while
501 * performing a set operation. Report to the application.
503 * @param cls the `struct GNUNET_SET_Handle`
504 * @param error error code
507 handle_client_set_error (void *cls,
508 enum GNUNET_MQ_Error error)
510 struct GNUNET_SET_Handle *set = cls;
512 LOG (GNUNET_ERROR_TYPE_DEBUG,
513 "Handling client set error %d\n",
515 while (NULL != set->ops_head)
517 if (NULL != set->ops_head->result_cb)
518 set->ops_head->result_cb (set->ops_head->result_cls,
520 GNUNET_SET_STATUS_FAILURE);
521 set_operation_destroy (set->ops_head);
523 set->invalid = GNUNET_YES;
524 if (GNUNET_YES == set->destroy_requested)
526 LOG (GNUNET_ERROR_TYPE_DEBUG,
527 "Destroying set after operation failure\n");
528 GNUNET_SET_destroy (set);
533 static struct GNUNET_SET_Handle *
534 create_internal (const struct GNUNET_CONFIGURATION_Handle *cfg,
535 enum GNUNET_SET_OperationType op,
538 static const struct GNUNET_MQ_MessageHandler mq_handlers[] = {
540 GNUNET_MESSAGE_TYPE_SET_RESULT,
542 { &handle_iter_element,
543 GNUNET_MESSAGE_TYPE_SET_ITER_ELEMENT,
546 GNUNET_MESSAGE_TYPE_SET_ITER_DONE,
547 sizeof (struct GNUNET_MessageHeader) },
549 GNUNET_MESSAGE_TYPE_SET_COPY_LAZY_RESPONSE,
550 sizeof (struct GNUNET_SET_CopyLazyResponseMessage) },
551 GNUNET_MQ_HANDLERS_END
553 struct GNUNET_SET_Handle *set;
554 struct GNUNET_MQ_Envelope *mqm;
555 struct GNUNET_SET_CreateMessage *create_msg;
556 struct GNUNET_SET_CopyLazyConnectMessage *copy_msg;
558 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
559 "Creating new set (operation %u)\n",
561 set = GNUNET_new (struct GNUNET_SET_Handle);
562 set->client = GNUNET_CLIENT_connect ("set", cfg);
564 if (NULL == set->client)
569 set->mq = GNUNET_MQ_queue_for_connection_client (set->client,
571 &handle_client_set_error,
573 GNUNET_assert (NULL != set->mq);
577 mqm = GNUNET_MQ_msg (create_msg,
578 GNUNET_MESSAGE_TYPE_SET_CREATE);
579 create_msg->operation = htonl (op);
583 mqm = GNUNET_MQ_msg (copy_msg,
584 GNUNET_MESSAGE_TYPE_SET_COPY_LAZY_CONNECT);
585 copy_msg->cookie = *cookie;
587 GNUNET_MQ_send (set->mq, mqm);
593 * Create an empty set, supporting the specified operation.
595 * @param cfg configuration to use for connecting to the
597 * @param op operation supported by the set
598 * Note that the operation has to be specified
599 * beforehand, as certain set operations need to maintain
600 * data structures spefific to the operation
601 * @return a handle to the set
603 struct GNUNET_SET_Handle *
604 GNUNET_SET_create (const struct GNUNET_CONFIGURATION_Handle *cfg,
605 enum GNUNET_SET_OperationType op)
607 return create_internal (cfg, op, NULL);
612 * Add an element to the given set. After the element has been added
613 * (in the sense of being transmitted to the set service), @a cont
614 * will be called. Multiple calls to GNUNET_SET_add_element() can be
617 * @param set set to add element to
618 * @param element element to add to the set
619 * @param cont continuation called after the element has been added
620 * @param cont_cls closure for @a cont
621 * @return #GNUNET_OK on success, #GNUNET_SYSERR if the
622 * set is invalid (e.g. the set service crashed)
625 GNUNET_SET_add_element (struct GNUNET_SET_Handle *set,
626 const struct GNUNET_SET_Element *element,
627 GNUNET_SET_Continuation cont,
630 struct GNUNET_MQ_Envelope *mqm;
631 struct GNUNET_SET_ElementMessage *msg;
633 if (GNUNET_YES == set->invalid)
637 return GNUNET_SYSERR;
639 mqm = GNUNET_MQ_msg_extra (msg, element->size,
640 GNUNET_MESSAGE_TYPE_SET_ADD);
641 msg->element_type = element->element_type;
645 GNUNET_MQ_notify_sent (mqm,
647 GNUNET_MQ_send (set->mq, mqm);
653 * Remove an element to the given set. After the element has been
654 * removed (in the sense of the request being transmitted to the set
655 * service), @a cont will be called. Multiple calls to
656 * GNUNET_SET_remove_element() can be queued
658 * @param set set to remove element from
659 * @param element element to remove from the set
660 * @param cont continuation called after the element has been removed
661 * @param cont_cls closure for @a cont
662 * @return #GNUNET_OK on success, #GNUNET_SYSERR if the
663 * set is invalid (e.g. the set service crashed)
666 GNUNET_SET_remove_element (struct GNUNET_SET_Handle *set,
667 const struct GNUNET_SET_Element *element,
668 GNUNET_SET_Continuation cont,
671 struct GNUNET_MQ_Envelope *mqm;
672 struct GNUNET_SET_ElementMessage *msg;
674 if (GNUNET_YES == set->invalid)
678 return GNUNET_SYSERR;
680 mqm = GNUNET_MQ_msg_extra (msg,
682 GNUNET_MESSAGE_TYPE_SET_REMOVE);
683 msg->element_type = element->element_type;
687 GNUNET_MQ_notify_sent (mqm,
689 GNUNET_MQ_send (set->mq, mqm);
695 * Destroy the set handle if no operations are left, mark the set
696 * for destruction otherwise.
698 * @param set set handle to destroy
701 GNUNET_SET_destroy (struct GNUNET_SET_Handle *set)
703 /* destroying set while iterator is active is currently
704 not supported; we should expand the API to allow
705 clients to explicitly cancel the iteration! */
706 GNUNET_assert (NULL == set->iterator);
707 if (NULL != set->ops_head)
709 LOG (GNUNET_ERROR_TYPE_DEBUG,
710 "Set operations are pending, delaying set destruction\n");
711 set->destroy_requested = GNUNET_YES;
714 LOG (GNUNET_ERROR_TYPE_DEBUG,
715 "Really destroying set\n");
716 if (NULL != set->client)
718 GNUNET_CLIENT_disconnect (set->client);
723 GNUNET_MQ_destroy (set->mq);
731 * Prepare a set operation to be evaluated with another peer.
732 * The evaluation will not start until the client provides
733 * a local set with #GNUNET_SET_commit().
735 * @param other_peer peer with the other set
736 * @param app_id hash for the application using the set
737 * @param context_msg additional information for the request
738 * @param result_mode specified how results will be returned,
739 * see `enum GNUNET_SET_ResultMode`.
740 * @param result_cb called on error or success
741 * @param result_cls closure for @e result_cb
742 * @return a handle to cancel the operation
744 struct GNUNET_SET_OperationHandle *
745 GNUNET_SET_prepare (const struct GNUNET_PeerIdentity *other_peer,
746 const struct GNUNET_HashCode *app_id,
747 const struct GNUNET_MessageHeader *context_msg,
748 enum GNUNET_SET_ResultMode result_mode,
749 GNUNET_SET_ResultIterator result_cb,
752 struct GNUNET_MQ_Envelope *mqm;
753 struct GNUNET_SET_OperationHandle *oh;
754 struct GNUNET_SET_EvaluateMessage *msg;
756 oh = GNUNET_new (struct GNUNET_SET_OperationHandle);
757 oh->result_cb = result_cb;
758 oh->result_cls = result_cls;
759 mqm = GNUNET_MQ_msg_nested_mh (msg,
760 GNUNET_MESSAGE_TYPE_SET_EVALUATE,
762 msg->app_id = *app_id;
763 msg->result_mode = htonl (result_mode);
764 msg->target_peer = *other_peer;
765 oh->conclude_mqm = mqm;
766 oh->request_id_addr = &msg->request_id;
773 * Connect to the set service in order to listen for requests.
775 * @param cls the `struct GNUNET_SET_ListenHandle *` to connect
776 * @param tc task context if invoked as a task, NULL otherwise
779 listen_connect (void *cls,
780 const struct GNUNET_SCHEDULER_TaskContext *tc);
784 * Handle request message for a listen operation
786 * @param cls the listen handle
787 * @param mh the message
790 handle_request (void *cls,
791 const struct GNUNET_MessageHeader *mh)
793 struct GNUNET_SET_ListenHandle *lh = cls;
794 const struct GNUNET_SET_RequestMessage *msg;
795 struct GNUNET_SET_Request req;
796 const struct GNUNET_MessageHeader *context_msg;
798 struct GNUNET_MQ_Envelope *mqm;
799 struct GNUNET_SET_RejectMessage *rmsg;
801 LOG (GNUNET_ERROR_TYPE_DEBUG,
802 "Processing incoming operation request\n");
803 msize = ntohs (mh->size);
804 if (msize < sizeof (struct GNUNET_SET_RequestMessage))
807 GNUNET_CLIENT_disconnect (lh->client);
809 GNUNET_MQ_destroy (lh->mq);
811 lh->reconnect_task = GNUNET_SCHEDULER_add_delayed (lh->reconnect_backoff,
812 &listen_connect, lh);
813 lh->reconnect_backoff = GNUNET_TIME_STD_BACKOFF (lh->reconnect_backoff);
816 /* we got another valid request => reset the backoff */
817 lh->reconnect_backoff = GNUNET_TIME_UNIT_MILLISECONDS;
818 msg = (const struct GNUNET_SET_RequestMessage *) mh;
819 req.accept_id = ntohl (msg->accept_id);
820 req.accepted = GNUNET_NO;
821 context_msg = GNUNET_MQ_extract_nested_mh (msg);
822 /* calling #GNUNET_SET_accept() in the listen cb will set req->accepted */
823 lh->listen_cb (lh->listen_cls,
827 if (GNUNET_YES == req.accepted)
828 return; /* the accept-case is handled in #GNUNET_SET_accept() */
829 LOG (GNUNET_ERROR_TYPE_DEBUG,
830 "Rejecting request\n");
831 mqm = GNUNET_MQ_msg (rmsg,
832 GNUNET_MESSAGE_TYPE_SET_REJECT);
833 rmsg->accept_reject_id = msg->accept_id;
834 GNUNET_MQ_send (lh->mq, mqm);
839 * Our connection with the set service encountered an error,
840 * re-initialize with exponential back-off.
842 * @param cls the `struct GNUNET_SET_ListenHandle *`
843 * @param error reason for the disconnect
846 handle_client_listener_error (void *cls,
847 enum GNUNET_MQ_Error error)
849 struct GNUNET_SET_ListenHandle *lh = cls;
851 LOG (GNUNET_ERROR_TYPE_DEBUG,
852 "Listener broke down (%d), re-connecting\n",
854 GNUNET_CLIENT_disconnect (lh->client);
856 GNUNET_MQ_destroy (lh->mq);
858 lh->reconnect_task = GNUNET_SCHEDULER_add_delayed (lh->reconnect_backoff,
859 &listen_connect, lh);
860 lh->reconnect_backoff = GNUNET_TIME_STD_BACKOFF (lh->reconnect_backoff);
865 * Connect to the set service in order to listen for requests.
867 * @param cls the `struct GNUNET_SET_ListenHandle *` to connect
868 * @param tc task context if invoked as a task, NULL otherwise
871 listen_connect (void *cls,
872 const struct GNUNET_SCHEDULER_TaskContext *tc)
874 static const struct GNUNET_MQ_MessageHandler mq_handlers[] = {
875 { &handle_request, GNUNET_MESSAGE_TYPE_SET_REQUEST },
876 GNUNET_MQ_HANDLERS_END
878 struct GNUNET_SET_ListenHandle *lh = cls;
879 struct GNUNET_MQ_Envelope *mqm;
880 struct GNUNET_SET_ListenMessage *msg;
883 (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN)) )
885 LOG (GNUNET_ERROR_TYPE_DEBUG,
886 "Listener not reconnecting due to shutdown\n");
889 lh->reconnect_task = NULL;
890 GNUNET_assert (NULL == lh->client);
891 lh->client = GNUNET_CLIENT_connect ("set", lh->cfg);
892 if (NULL == lh->client)
894 GNUNET_assert (NULL == lh->mq);
895 lh->mq = GNUNET_MQ_queue_for_connection_client (lh->client,
897 &handle_client_listener_error, lh);
898 mqm = GNUNET_MQ_msg (msg, GNUNET_MESSAGE_TYPE_SET_LISTEN);
899 msg->operation = htonl (lh->operation);
900 msg->app_id = lh->app_id;
901 GNUNET_MQ_send (lh->mq, mqm);
906 * Wait for set operation requests for the given application id
908 * @param cfg configuration to use for connecting to
909 * the set service, needs to be valid for the lifetime of the listen handle
910 * @param operation operation we want to listen for
911 * @param app_id id of the application that handles set operation requests
912 * @param listen_cb called for each incoming request matching the operation
914 * @param listen_cls handle for @a listen_cb
915 * @return a handle that can be used to cancel the listen operation
917 struct GNUNET_SET_ListenHandle *
918 GNUNET_SET_listen (const struct GNUNET_CONFIGURATION_Handle *cfg,
919 enum GNUNET_SET_OperationType operation,
920 const struct GNUNET_HashCode *app_id,
921 GNUNET_SET_ListenCallback listen_cb,
924 struct GNUNET_SET_ListenHandle *lh;
926 lh = GNUNET_new (struct GNUNET_SET_ListenHandle);
927 lh->listen_cb = listen_cb;
928 lh->listen_cls = listen_cls;
930 lh->operation = operation;
931 lh->app_id = *app_id;
932 lh->reconnect_backoff = GNUNET_TIME_UNIT_MILLISECONDS;
933 listen_connect (lh, NULL);
934 if (NULL == lh->client)
944 * Cancel the given listen operation.
946 * @param lh handle for the listen operation
949 GNUNET_SET_listen_cancel (struct GNUNET_SET_ListenHandle *lh)
951 LOG (GNUNET_ERROR_TYPE_DEBUG,
952 "Canceling listener\n");
955 GNUNET_MQ_destroy (lh->mq);
958 if (NULL != lh->client)
960 GNUNET_CLIENT_disconnect (lh->client);
963 if (NULL != lh->reconnect_task)
965 GNUNET_SCHEDULER_cancel (lh->reconnect_task);
966 lh->reconnect_task = NULL;
973 * Accept a request we got via #GNUNET_SET_listen. Must be called during
974 * #GNUNET_SET_listen, as the 'struct GNUNET_SET_Request' becomes invalid
976 * Call #GNUNET_SET_commit to provide the local set to use for the operation,
977 * and to begin the exchange with the remote peer.
979 * @param request request to accept
980 * @param result_mode specified how results will be returned,
981 * see `enum GNUNET_SET_ResultMode`.
982 * @param result_cb callback for the results
983 * @param result_cls closure for @a result_cb
984 * @return a handle to cancel the operation
986 struct GNUNET_SET_OperationHandle *
987 GNUNET_SET_accept (struct GNUNET_SET_Request *request,
988 enum GNUNET_SET_ResultMode result_mode,
989 GNUNET_SET_ResultIterator result_cb,
992 struct GNUNET_MQ_Envelope *mqm;
993 struct GNUNET_SET_OperationHandle *oh;
994 struct GNUNET_SET_AcceptMessage *msg;
996 GNUNET_assert (GNUNET_NO == request->accepted);
997 request->accepted = GNUNET_YES;
998 mqm = GNUNET_MQ_msg (msg, GNUNET_MESSAGE_TYPE_SET_ACCEPT);
999 msg->accept_reject_id = htonl (request->accept_id);
1000 msg->result_mode = htonl (result_mode);
1001 oh = GNUNET_new (struct GNUNET_SET_OperationHandle);
1002 oh->result_cb = result_cb;
1003 oh->result_cls = result_cls;
1004 oh->conclude_mqm = mqm;
1005 oh->request_id_addr = &msg->request_id;
1011 * Commit a set to be used with a set operation.
1012 * This function is called once we have fully constructed
1013 * the set that we want to use for the operation. At this
1014 * time, the P2P protocol can then begin to exchange the
1015 * set information and call the result callback with the
1016 * result information.
1018 * @param oh handle to the set operation
1019 * @param set the set to use for the operation
1020 * @return #GNUNET_OK on success, #GNUNET_SYSERR if the
1021 * set is invalid (e.g. the set service crashed)
1024 GNUNET_SET_commit (struct GNUNET_SET_OperationHandle *oh,
1025 struct GNUNET_SET_Handle *set)
1027 GNUNET_assert (NULL == oh->set);
1028 if (GNUNET_YES == set->invalid)
1029 return GNUNET_SYSERR;
1030 GNUNET_assert (NULL != oh->conclude_mqm);
1032 GNUNET_CONTAINER_DLL_insert (set->ops_head,
1035 oh->request_id = GNUNET_MQ_assoc_add (set->mq, oh);
1036 *oh->request_id_addr = htonl (oh->request_id);
1037 GNUNET_MQ_send (set->mq, oh->conclude_mqm);
1038 oh->conclude_mqm = NULL;
1039 oh->request_id_addr = NULL;
1045 * Iterate over all elements in the given set. Note that this
1046 * operation involves transferring every element of the set from the
1047 * service to the client, and is thus costly.
1049 * @param set the set to iterate over
1050 * @param iter the iterator to call for each element
1051 * @param iter_cls closure for @a iter
1052 * @return #GNUNET_YES if the iteration started successfuly,
1053 * #GNUNET_NO if another iteration is active
1054 * #GNUNET_SYSERR if the set is invalid (e.g. the server crashed, disconnected)
1057 GNUNET_SET_iterate (struct GNUNET_SET_Handle *set,
1058 GNUNET_SET_ElementIterator iter,
1061 struct GNUNET_MQ_Envelope *ev;
1063 GNUNET_assert (NULL != iter);
1064 if (GNUNET_YES == set->invalid)
1065 return GNUNET_SYSERR;
1066 if (NULL != set->iterator)
1068 LOG (GNUNET_ERROR_TYPE_DEBUG,
1069 "Iterating over set\n");
1070 set->iterator = iter;
1071 set->iterator_cls = iter_cls;
1072 ev = GNUNET_MQ_msg_header (GNUNET_MESSAGE_TYPE_SET_ITER_REQUEST);
1073 GNUNET_MQ_send (set->mq, ev);
1079 GNUNET_SET_copy_lazy (struct GNUNET_SET_Handle *set,
1080 GNUNET_SET_CopyReadyCallback cb,
1083 struct GNUNET_MQ_Envelope *ev;
1084 struct SetCopyRequest *req;
1086 ev = GNUNET_MQ_msg_header (GNUNET_MESSAGE_TYPE_SET_COPY_LAZY_PREPARE);
1087 GNUNET_MQ_send (set->mq, ev);
1089 req = GNUNET_new (struct SetCopyRequest);
1092 GNUNET_CONTAINER_DLL_insert (set->copy_req_head,
1098 /* end of set_api.c */