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3 Copyright (C) 2012-2016 GNUnet e.V.
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6 it under the terms of the GNU General Public License as published
7 by the Free Software Foundation; either version 3, 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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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_set_service.h"
33 #define LOG(kind,...) GNUNET_log_from (kind, "set-api",__VA_ARGS__)
37 struct SetCopyRequest *next;
39 struct SetCopyRequest *prev;
43 GNUNET_SET_CopyReadyCallback cb;
47 * Opaque handle to a set.
49 struct GNUNET_SET_Handle
52 * Message queue for @e client.
54 struct GNUNET_MQ_Handle *mq;
57 * Linked list of operations on the set.
59 struct GNUNET_SET_OperationHandle *ops_head;
62 * Linked list of operations on the set.
64 struct GNUNET_SET_OperationHandle *ops_tail;
67 * Callback for the current iteration over the set,
68 * NULL if no iterator is active.
70 GNUNET_SET_ElementIterator iterator;
73 * Closure for @e iterator
78 * Should the set be destroyed once all operations are gone?
80 int destroy_requested;
83 * Has the set become invalid (e.g. service died)?
88 * Both client and service count the number of iterators
89 * created so far to match replies with iterators.
91 uint16_t iteration_id;
94 * Configuration, needed when creating (lazy) copies.
96 const struct GNUNET_CONFIGURATION_Handle *cfg;
99 * Doubly linked list of copy requests.
101 struct SetCopyRequest *copy_req_head;
104 * Doubly linked list of copy requests.
106 struct SetCopyRequest *copy_req_tail;
111 * Handle for a set operation request from another peer.
113 struct GNUNET_SET_Request
116 * Id of the request, used to identify the request when
117 * accepting/rejecting it.
122 * Has the request been accepted already?
123 * #GNUNET_YES/#GNUNET_NO
130 * Handle to an operation. Only known to the service after committing
131 * the handle with a set.
133 struct GNUNET_SET_OperationHandle
136 * Function to be called when we have a result,
139 GNUNET_SET_ResultIterator result_cb;
142 * Closure for @e result_cb.
147 * Local set used for the operation,
148 * NULL if no set has been provided by conclude yet.
150 struct GNUNET_SET_Handle *set;
153 * Message sent to the server on calling conclude,
154 * NULL if conclude has been called.
156 struct GNUNET_MQ_Envelope *conclude_mqm;
159 * Address of the request if in the conclude message,
160 * used to patch the request id into the message when the set is known.
162 uint32_t *request_id_addr;
165 * Handles are kept in a linked list.
167 struct GNUNET_SET_OperationHandle *prev;
170 * Handles are kept in a linked list.
172 struct GNUNET_SET_OperationHandle *next;
175 * Request ID to identify the operation within the set.
182 * Opaque handle to a listen operation.
184 struct GNUNET_SET_ListenHandle
188 * Message queue for the client.
190 struct GNUNET_MQ_Handle* mq;
193 * Configuration handle for the listener, stored
194 * here to be able to reconnect transparently on
195 * connection failure.
197 const struct GNUNET_CONFIGURATION_Handle *cfg;
200 * Function to call on a new incoming request,
203 GNUNET_SET_ListenCallback listen_cb;
206 * Closure for @e listen_cb.
211 * Application ID we listen for.
213 struct GNUNET_HashCode app_id;
216 * Time to wait until we try to reconnect on failure.
218 struct GNUNET_TIME_Relative reconnect_backoff;
221 * Task for reconnecting when the listener fails.
223 struct GNUNET_SCHEDULER_Task *reconnect_task;
226 * Operation we listen for.
228 enum GNUNET_SET_OperationType operation;
232 /* mutual recursion with handle_copy_lazy */
233 static struct GNUNET_SET_Handle *
234 create_internal (const struct GNUNET_CONFIGURATION_Handle *cfg,
235 enum GNUNET_SET_OperationType op,
236 const uint32_t *cookie);
240 * Handle element for iteration over the set. Notifies the
241 * iterator and sends an acknowledgement to the service.
243 * @param cls the `struct GNUNET_SET_Handle *`
244 * @param msg the message
247 handle_copy_lazy (void *cls,
248 const struct GNUNET_SET_CopyLazyResponseMessage *msg)
250 struct GNUNET_SET_Handle *set = cls;
251 struct SetCopyRequest *req;
252 struct GNUNET_SET_Handle *new_set;
254 req = set->copy_req_head;
257 /* Service sent us unsolicited lazy copy response */
262 LOG (GNUNET_ERROR_TYPE_DEBUG,
263 "Handling response to lazy copy\n");
264 GNUNET_CONTAINER_DLL_remove (set->copy_req_head,
267 // We pass none as operation here, since it doesn't matter when
269 new_set = create_internal (set->cfg,
270 GNUNET_SET_OPERATION_NONE,
272 req->cb (req->cls, new_set);
278 * Check that the given @a msg is well-formed.
281 * @param msg message to check
282 * @return #GNUNET_OK if message is well-formed
285 check_iter_element (void *cls,
286 const struct GNUNET_SET_IterResponseMessage *msg)
288 /* minimum size was already checked, everything else is OK! */
294 * Handle element for iteration over the set. Notifies the
295 * iterator and sends an acknowledgement to the service.
297 * @param cls the `struct GNUNET_SET_Handle *`
298 * @param mh the message
301 handle_iter_element (void *cls,
302 const struct GNUNET_SET_IterResponseMessage *msg)
304 struct GNUNET_SET_Handle *set = cls;
305 GNUNET_SET_ElementIterator iter = set->iterator;
306 struct GNUNET_SET_Element element;
307 struct GNUNET_SET_IterAckMessage *ack_msg;
308 struct GNUNET_MQ_Envelope *ev;
311 msize = ntohs (msg->header.size);
312 if (set->iteration_id != ntohs (msg->iteration_id))
314 /* element from a previous iteration, skip! */
319 element.size = msize - sizeof (struct GNUNET_SET_IterResponseMessage);
320 element.element_type = ntohs (msg->element_type);
321 element.data = &msg[1];
322 iter (set->iterator_cls,
325 ev = GNUNET_MQ_msg (ack_msg,
326 GNUNET_MESSAGE_TYPE_SET_ITER_ACK);
327 ack_msg->send_more = htonl ((NULL != iter));
328 GNUNET_MQ_send (set->mq, ev);
333 * Handle message signalling conclusion of iteration over the set.
334 * Notifies the iterator that we are done.
337 * @param mh the message
340 handle_iter_done (void *cls,
341 const struct GNUNET_MessageHeader *mh)
343 struct GNUNET_SET_Handle *set = cls;
344 GNUNET_SET_ElementIterator iter = set->iterator;
348 set->iterator = NULL;
350 iter (set->iterator_cls,
356 * Check that the given @a msg is well-formed.
359 * @param msg message to check
360 * @return #GNUNET_OK if message is well-formed
363 check_result (void *cls,
364 const struct GNUNET_SET_ResultMessage *msg)
366 /* minimum size was already checked, everything else is OK! */
372 * Handle result message for a set operation.
375 * @param mh the message
378 handle_result (void *cls,
379 const struct GNUNET_SET_ResultMessage *msg)
381 struct GNUNET_SET_Handle *set = cls;
382 struct GNUNET_SET_OperationHandle *oh;
383 struct GNUNET_SET_Element e;
384 enum GNUNET_SET_Status result_status;
387 GNUNET_assert (NULL != set->mq);
388 result_status = ntohs (msg->result_status);
389 LOG (GNUNET_ERROR_TYPE_DEBUG,
390 "Got result message with status %d\n",
393 oh = GNUNET_MQ_assoc_get (set->mq,
394 ntohl (msg->request_id));
397 /* 'oh' can be NULL if we canceled the operation, but the service
398 did not get the cancel message yet. */
399 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
400 "Ignoring result from canceled operation\n");
404 switch (result_status)
406 case GNUNET_SET_STATUS_OK:
407 case GNUNET_SET_STATUS_ADD_LOCAL:
408 case GNUNET_SET_STATUS_ADD_REMOTE:
410 case GNUNET_SET_STATUS_FAILURE:
411 case GNUNET_SET_STATUS_DONE:
413 case GNUNET_SET_STATUS_HALF_DONE:
414 /* not used anymore */
419 LOG (GNUNET_ERROR_TYPE_DEBUG,
420 "Treating result as final status\n");
421 GNUNET_MQ_assoc_remove (set->mq,
422 ntohl (msg->request_id));
423 GNUNET_CONTAINER_DLL_remove (set->ops_head,
426 /* Need to do this calculation _before_ the result callback,
427 as IF the application still has a valid set handle, it
428 may trigger destruction of the set during the callback. */
429 destroy_set = (GNUNET_YES == set->destroy_requested) &&
430 (NULL == set->ops_head);
431 if (NULL != oh->result_cb)
433 oh->result_cb (oh->result_cls,
435 GNUNET_ntohll (msg->current_size),
440 LOG (GNUNET_ERROR_TYPE_DEBUG,
441 "No callback for final status\n");
444 GNUNET_SET_destroy (set);
449 LOG (GNUNET_ERROR_TYPE_DEBUG,
450 "Treating result as element\n");
452 e.size = ntohs (msg->header.size) - sizeof (struct GNUNET_SET_ResultMessage);
453 e.element_type = ntohs (msg->element_type);
454 if (NULL != oh->result_cb)
455 oh->result_cb (oh->result_cls,
457 GNUNET_ntohll (msg->current_size),
463 * Destroy the given set operation.
465 * @param oh set operation to destroy
468 set_operation_destroy (struct GNUNET_SET_OperationHandle *oh)
470 struct GNUNET_SET_Handle *set = oh->set;
471 struct GNUNET_SET_OperationHandle *h_assoc;
473 if (NULL != oh->conclude_mqm)
474 GNUNET_MQ_discard (oh->conclude_mqm);
475 /* is the operation already commited? */
478 GNUNET_CONTAINER_DLL_remove (set->ops_head,
481 h_assoc = GNUNET_MQ_assoc_remove (set->mq,
483 GNUNET_assert ((NULL == h_assoc) || (h_assoc == oh));
490 * Cancel the given set operation. We need to send an explicit cancel
491 * message, as all operations one one set communicate using one
494 * @param oh set operation to cancel
497 GNUNET_SET_operation_cancel (struct GNUNET_SET_OperationHandle *oh)
499 struct GNUNET_SET_Handle *set = oh->set;
500 struct GNUNET_SET_CancelMessage *m;
501 struct GNUNET_MQ_Envelope *mqm;
505 mqm = GNUNET_MQ_msg (m, GNUNET_MESSAGE_TYPE_SET_CANCEL);
506 m->request_id = htonl (oh->request_id);
507 GNUNET_MQ_send (set->mq, mqm);
509 set_operation_destroy (oh);
510 if ( (NULL != set) &&
511 (GNUNET_YES == set->destroy_requested) &&
512 (NULL == set->ops_head) )
514 LOG (GNUNET_ERROR_TYPE_DEBUG,
515 "Destroying set after operation cancel\n");
516 GNUNET_SET_destroy (set);
522 * We encountered an error communicating with the set service while
523 * performing a set operation. Report to the application.
525 * @param cls the `struct GNUNET_SET_Handle`
526 * @param error error code
529 handle_client_set_error (void *cls,
530 enum GNUNET_MQ_Error error)
532 struct GNUNET_SET_Handle *set = cls;
533 GNUNET_SET_ElementIterator iter = set->iterator;
535 LOG (GNUNET_ERROR_TYPE_ERROR,
536 "Handling client set error %d\n",
538 while (NULL != set->ops_head)
540 if (NULL != set->ops_head->result_cb)
541 set->ops_head->result_cb (set->ops_head->result_cls,
544 GNUNET_SET_STATUS_FAILURE);
545 set_operation_destroy (set->ops_head);
547 set->iterator = NULL;
549 set->invalid = GNUNET_YES;
551 iter (set->iterator_cls,
556 static struct GNUNET_SET_Handle *
557 create_internal (const struct GNUNET_CONFIGURATION_Handle *cfg,
558 enum GNUNET_SET_OperationType op,
559 const uint32_t *cookie)
561 struct GNUNET_SET_Handle *set = GNUNET_new (struct GNUNET_SET_Handle);
562 struct GNUNET_MQ_MessageHandler mq_handlers[] = {
563 GNUNET_MQ_hd_var_size (result,
564 GNUNET_MESSAGE_TYPE_SET_RESULT,
565 struct GNUNET_SET_ResultMessage,
567 GNUNET_MQ_hd_var_size (iter_element,
568 GNUNET_MESSAGE_TYPE_SET_ITER_ELEMENT,
569 struct GNUNET_SET_IterResponseMessage,
571 GNUNET_MQ_hd_fixed_size (iter_done,
572 GNUNET_MESSAGE_TYPE_SET_ITER_DONE,
573 struct GNUNET_MessageHeader,
575 GNUNET_MQ_hd_fixed_size (copy_lazy,
576 GNUNET_MESSAGE_TYPE_SET_COPY_LAZY_RESPONSE,
577 struct GNUNET_SET_CopyLazyResponseMessage,
579 GNUNET_MQ_handler_end ()
581 struct GNUNET_MQ_Envelope *mqm;
582 struct GNUNET_SET_CreateMessage *create_msg;
583 struct GNUNET_SET_CopyLazyConnectMessage *copy_msg;
586 set->mq = GNUNET_CLIENT_connect (cfg,
589 &handle_client_set_error,
598 LOG (GNUNET_ERROR_TYPE_DEBUG,
599 "Creating new set (operation %u)\n",
601 mqm = GNUNET_MQ_msg (create_msg,
602 GNUNET_MESSAGE_TYPE_SET_CREATE);
603 create_msg->operation = htonl (op);
607 LOG (GNUNET_ERROR_TYPE_DEBUG,
608 "Creating new set (lazy copy)\n",
610 mqm = GNUNET_MQ_msg (copy_msg,
611 GNUNET_MESSAGE_TYPE_SET_COPY_LAZY_CONNECT);
612 copy_msg->cookie = *cookie;
614 GNUNET_MQ_send (set->mq, mqm);
620 * Create an empty set, supporting the specified operation.
622 * @param cfg configuration to use for connecting to the
624 * @param op operation supported by the set
625 * Note that the operation has to be specified
626 * beforehand, as certain set operations need to maintain
627 * data structures spefific to the operation
628 * @return a handle to the set
630 struct GNUNET_SET_Handle *
631 GNUNET_SET_create (const struct GNUNET_CONFIGURATION_Handle *cfg,
632 enum GNUNET_SET_OperationType op)
634 return create_internal (cfg, op, NULL);
639 * Add an element to the given set. After the element has been added
640 * (in the sense of being transmitted to the set service), @a cont
641 * will be called. Multiple calls to GNUNET_SET_add_element() can be
644 * @param set set to add element to
645 * @param element element to add to the set
646 * @param cont continuation called after the element has been added
647 * @param cont_cls closure for @a cont
648 * @return #GNUNET_OK on success, #GNUNET_SYSERR if the
649 * set is invalid (e.g. the set service crashed)
652 GNUNET_SET_add_element (struct GNUNET_SET_Handle *set,
653 const struct GNUNET_SET_Element *element,
654 GNUNET_SET_Continuation cont,
657 struct GNUNET_MQ_Envelope *mqm;
658 struct GNUNET_SET_ElementMessage *msg;
660 LOG (GNUNET_ERROR_TYPE_INFO, "adding element of type %u\n", (unsigned) element->element_type);
662 if (GNUNET_YES == set->invalid)
666 return GNUNET_SYSERR;
668 mqm = GNUNET_MQ_msg_extra (msg,
670 GNUNET_MESSAGE_TYPE_SET_ADD);
671 msg->element_type = htons (element->element_type);
672 GNUNET_memcpy (&msg[1],
675 GNUNET_MQ_notify_sent (mqm,
677 GNUNET_MQ_send (set->mq, mqm);
683 * Remove an element to the given set. After the element has been
684 * removed (in the sense of the request being transmitted to the set
685 * service), @a cont will be called. Multiple calls to
686 * GNUNET_SET_remove_element() can be queued
688 * @param set set to remove element from
689 * @param element element to remove from the set
690 * @param cont continuation called after the element has been removed
691 * @param cont_cls closure for @a cont
692 * @return #GNUNET_OK on success, #GNUNET_SYSERR if the
693 * set is invalid (e.g. the set service crashed)
696 GNUNET_SET_remove_element (struct GNUNET_SET_Handle *set,
697 const struct GNUNET_SET_Element *element,
698 GNUNET_SET_Continuation cont,
701 struct GNUNET_MQ_Envelope *mqm;
702 struct GNUNET_SET_ElementMessage *msg;
704 if (GNUNET_YES == set->invalid)
708 return GNUNET_SYSERR;
710 mqm = GNUNET_MQ_msg_extra (msg,
712 GNUNET_MESSAGE_TYPE_SET_REMOVE);
713 msg->element_type = htons (element->element_type);
714 GNUNET_memcpy (&msg[1],
717 GNUNET_MQ_notify_sent (mqm,
719 GNUNET_MQ_send (set->mq, mqm);
725 * Destroy the set handle if no operations are left, mark the set
726 * for destruction otherwise.
728 * @param set set handle to destroy
731 GNUNET_SET_destroy (struct GNUNET_SET_Handle *set)
733 /* destroying set while iterator is active is currently
734 not supported; we should expand the API to allow
735 clients to explicitly cancel the iteration! */
736 GNUNET_assert (NULL == set->iterator);
737 if (NULL != set->ops_head)
739 LOG (GNUNET_ERROR_TYPE_DEBUG,
740 "Set operations are pending, delaying set destruction\n");
741 set->destroy_requested = GNUNET_YES;
744 LOG (GNUNET_ERROR_TYPE_DEBUG,
745 "Really destroying set\n");
748 GNUNET_MQ_destroy (set->mq);
756 * Prepare a set operation to be evaluated with another peer.
757 * The evaluation will not start until the client provides
758 * a local set with #GNUNET_SET_commit().
760 * @param other_peer peer with the other set
761 * @param app_id hash for the application using the set
762 * @param context_msg additional information for the request
763 * @param result_mode specified how results will be returned,
764 * see `enum GNUNET_SET_ResultMode`.
765 * @param result_cb called on error or success
766 * @param result_cls closure for @e result_cb
767 * @return a handle to cancel the operation
769 struct GNUNET_SET_OperationHandle *
770 GNUNET_SET_prepare (const struct GNUNET_PeerIdentity *other_peer,
771 const struct GNUNET_HashCode *app_id,
772 const struct GNUNET_MessageHeader *context_msg,
773 enum GNUNET_SET_ResultMode result_mode,
774 struct GNUNET_SET_Option options[],
775 GNUNET_SET_ResultIterator result_cb,
778 struct GNUNET_MQ_Envelope *mqm;
779 struct GNUNET_SET_OperationHandle *oh;
780 struct GNUNET_SET_EvaluateMessage *msg;
781 struct GNUNET_SET_Option *opt;
783 LOG (GNUNET_ERROR_TYPE_DEBUG,
784 "Client prepares set operation (%d)\n",
786 oh = GNUNET_new (struct GNUNET_SET_OperationHandle);
787 oh->result_cb = result_cb;
788 oh->result_cls = result_cls;
789 mqm = GNUNET_MQ_msg_nested_mh (msg,
790 GNUNET_MESSAGE_TYPE_SET_EVALUATE,
792 msg->app_id = *app_id;
793 msg->result_mode = htonl (result_mode);
794 msg->target_peer = *other_peer;
795 for (opt = options; opt->type != 0; opt++)
799 case GNUNET_SET_OPTION_BYZANTINE:
800 msg->byzantine = GNUNET_YES;
801 msg->byzantine_lower_bound = opt->v.num;
803 case GNUNET_SET_OPTION_FORCE_FULL:
804 msg->force_full = GNUNET_YES;
806 case GNUNET_SET_OPTION_FORCE_DELTA:
807 msg->force_delta = GNUNET_YES;
810 LOG (GNUNET_ERROR_TYPE_ERROR,
811 "Option with type %d not recognized\n", (int) opt->type);
814 oh->conclude_mqm = mqm;
815 oh->request_id_addr = &msg->request_id;
822 * Connect to the set service in order to listen for requests.
824 * @param cls the `struct GNUNET_SET_ListenHandle *` to connect
827 listen_connect (void *cls);
831 * Check validity of request message for a listen operation
833 * @param cls the listen handle
834 * @param msg the message
835 * @return #GNUNET_OK if the message is well-formed
838 check_request (void *cls,
839 const struct GNUNET_SET_RequestMessage *msg)
841 const struct GNUNET_MessageHeader *context_msg;
843 if (ntohs (msg->header.size) == sizeof (*msg))
844 return GNUNET_OK; /* no context message is OK */
845 context_msg = GNUNET_MQ_extract_nested_mh (msg);
846 if (NULL == context_msg)
848 /* malformed context message is NOT ok */
850 return GNUNET_SYSERR;
857 * Handle request message for a listen operation
859 * @param cls the listen handle
860 * @param msg the message
863 handle_request (void *cls,
864 const struct GNUNET_SET_RequestMessage *msg)
866 struct GNUNET_SET_ListenHandle *lh = cls;
867 struct GNUNET_SET_Request req;
868 const struct GNUNET_MessageHeader *context_msg;
869 struct GNUNET_MQ_Envelope *mqm;
870 struct GNUNET_SET_RejectMessage *rmsg;
872 LOG (GNUNET_ERROR_TYPE_DEBUG,
873 "Processing incoming operation request\n");
874 /* we got another valid request => reset the backoff */
875 lh->reconnect_backoff = GNUNET_TIME_UNIT_MILLISECONDS;
876 req.accept_id = ntohl (msg->accept_id);
877 req.accepted = GNUNET_NO;
878 context_msg = GNUNET_MQ_extract_nested_mh (msg);
879 /* calling #GNUNET_SET_accept() in the listen cb will set req->accepted */
880 lh->listen_cb (lh->listen_cls,
884 if (GNUNET_YES == req.accepted)
885 return; /* the accept-case is handled in #GNUNET_SET_accept() */
886 LOG (GNUNET_ERROR_TYPE_DEBUG,
887 "Rejecting request\n");
888 mqm = GNUNET_MQ_msg (rmsg,
889 GNUNET_MESSAGE_TYPE_SET_REJECT);
890 rmsg->accept_reject_id = msg->accept_id;
891 GNUNET_MQ_send (lh->mq, mqm);
896 * Our connection with the set service encountered an error,
897 * re-initialize with exponential back-off.
899 * @param cls the `struct GNUNET_SET_ListenHandle *`
900 * @param error reason for the disconnect
903 handle_client_listener_error (void *cls,
904 enum GNUNET_MQ_Error error)
906 struct GNUNET_SET_ListenHandle *lh = cls;
908 LOG (GNUNET_ERROR_TYPE_DEBUG,
909 "Listener broke down (%d), re-connecting\n",
911 GNUNET_MQ_destroy (lh->mq);
913 lh->reconnect_task = GNUNET_SCHEDULER_add_delayed (lh->reconnect_backoff,
916 lh->reconnect_backoff = GNUNET_TIME_STD_BACKOFF (lh->reconnect_backoff);
921 * Connect to the set service in order to listen for requests.
923 * @param cls the `struct GNUNET_SET_ListenHandle *` to connect
926 listen_connect (void *cls)
928 struct GNUNET_SET_ListenHandle *lh = cls;
929 struct GNUNET_MQ_MessageHandler mq_handlers[] = {
930 GNUNET_MQ_hd_var_size (request,
931 GNUNET_MESSAGE_TYPE_SET_REQUEST,
932 struct GNUNET_SET_RequestMessage,
934 GNUNET_MQ_handler_end ()
936 struct GNUNET_MQ_Envelope *mqm;
937 struct GNUNET_SET_ListenMessage *msg;
939 lh->reconnect_task = NULL;
940 GNUNET_assert (NULL == lh->mq);
941 lh->mq = GNUNET_CLIENT_connect (lh->cfg,
944 &handle_client_listener_error,
948 mqm = GNUNET_MQ_msg (msg, GNUNET_MESSAGE_TYPE_SET_LISTEN);
949 msg->operation = htonl (lh->operation);
950 msg->app_id = lh->app_id;
951 GNUNET_MQ_send (lh->mq,
957 * Wait for set operation requests for the given application id
959 * @param cfg configuration to use for connecting to
960 * the set service, needs to be valid for the lifetime of the listen handle
961 * @param operation operation we want to listen for
962 * @param app_id id of the application that handles set operation requests
963 * @param listen_cb called for each incoming request matching the operation
965 * @param listen_cls handle for @a listen_cb
966 * @return a handle that can be used to cancel the listen operation
968 struct GNUNET_SET_ListenHandle *
969 GNUNET_SET_listen (const struct GNUNET_CONFIGURATION_Handle *cfg,
970 enum GNUNET_SET_OperationType operation,
971 const struct GNUNET_HashCode *app_id,
972 GNUNET_SET_ListenCallback listen_cb,
975 struct GNUNET_SET_ListenHandle *lh;
977 lh = GNUNET_new (struct GNUNET_SET_ListenHandle);
978 lh->listen_cb = listen_cb;
979 lh->listen_cls = listen_cls;
981 lh->operation = operation;
982 lh->app_id = *app_id;
983 lh->reconnect_backoff = GNUNET_TIME_UNIT_MILLISECONDS;
995 * Cancel the given listen operation.
997 * @param lh handle for the listen operation
1000 GNUNET_SET_listen_cancel (struct GNUNET_SET_ListenHandle *lh)
1002 LOG (GNUNET_ERROR_TYPE_DEBUG,
1003 "Canceling listener\n");
1006 GNUNET_MQ_destroy (lh->mq);
1009 if (NULL != lh->reconnect_task)
1011 GNUNET_SCHEDULER_cancel (lh->reconnect_task);
1012 lh->reconnect_task = NULL;
1019 * Accept a request we got via #GNUNET_SET_listen. Must be called during
1020 * #GNUNET_SET_listen, as the 'struct GNUNET_SET_Request' becomes invalid
1022 * Call #GNUNET_SET_commit to provide the local set to use for the operation,
1023 * and to begin the exchange with the remote peer.
1025 * @param request request to accept
1026 * @param result_mode specified how results will be returned,
1027 * see `enum GNUNET_SET_ResultMode`.
1028 * @param result_cb callback for the results
1029 * @param result_cls closure for @a result_cb
1030 * @return a handle to cancel the operation
1032 struct GNUNET_SET_OperationHandle *
1033 GNUNET_SET_accept (struct GNUNET_SET_Request *request,
1034 enum GNUNET_SET_ResultMode result_mode,
1035 struct GNUNET_SET_Option options[],
1036 GNUNET_SET_ResultIterator result_cb,
1039 struct GNUNET_MQ_Envelope *mqm;
1040 struct GNUNET_SET_OperationHandle *oh;
1041 struct GNUNET_SET_AcceptMessage *msg;
1043 GNUNET_assert (GNUNET_NO == request->accepted);
1044 LOG (GNUNET_ERROR_TYPE_DEBUG,
1045 "Client accepts set operation (%d)\n",
1047 request->accepted = GNUNET_YES;
1048 mqm = GNUNET_MQ_msg (msg, GNUNET_MESSAGE_TYPE_SET_ACCEPT);
1049 msg->accept_reject_id = htonl (request->accept_id);
1050 msg->result_mode = htonl (result_mode);
1051 oh = GNUNET_new (struct GNUNET_SET_OperationHandle);
1052 oh->result_cb = result_cb;
1053 oh->result_cls = result_cls;
1054 oh->conclude_mqm = mqm;
1055 oh->request_id_addr = &msg->request_id;
1061 * Commit a set to be used with a set operation.
1062 * This function is called once we have fully constructed
1063 * the set that we want to use for the operation. At this
1064 * time, the P2P protocol can then begin to exchange the
1065 * set information and call the result callback with the
1066 * result information.
1068 * @param oh handle to the set operation
1069 * @param set the set to use for the operation
1070 * @return #GNUNET_OK on success, #GNUNET_SYSERR if the
1071 * set is invalid (e.g. the set service crashed)
1074 GNUNET_SET_commit (struct GNUNET_SET_OperationHandle *oh,
1075 struct GNUNET_SET_Handle *set)
1077 if (NULL != oh->set)
1079 /* Some other set was already commited for this
1080 * operation, there is a logic bug in the client of this API */
1084 if (GNUNET_YES == set->invalid)
1085 return GNUNET_SYSERR;
1086 LOG (GNUNET_ERROR_TYPE_DEBUG,
1087 "Client commits to SET\n");
1088 GNUNET_assert (NULL != oh->conclude_mqm);
1090 GNUNET_CONTAINER_DLL_insert (set->ops_head,
1093 oh->request_id = GNUNET_MQ_assoc_add (set->mq,
1095 *oh->request_id_addr = htonl (oh->request_id);
1096 GNUNET_MQ_send (set->mq,
1098 oh->conclude_mqm = NULL;
1099 oh->request_id_addr = NULL;
1105 * Iterate over all elements in the given set. Note that this
1106 * operation involves transferring every element of the set from the
1107 * service to the client, and is thus costly.
1109 * @param set the set to iterate over
1110 * @param iter the iterator to call for each element
1111 * @param iter_cls closure for @a iter
1112 * @return #GNUNET_YES if the iteration started successfuly,
1113 * #GNUNET_NO if another iteration is active
1114 * #GNUNET_SYSERR if the set is invalid (e.g. the server crashed, disconnected)
1117 GNUNET_SET_iterate (struct GNUNET_SET_Handle *set,
1118 GNUNET_SET_ElementIterator iter,
1121 struct GNUNET_MQ_Envelope *ev;
1123 GNUNET_assert (NULL != iter);
1124 if (GNUNET_YES == set->invalid)
1125 return GNUNET_SYSERR;
1126 if (NULL != set->iterator)
1128 LOG (GNUNET_ERROR_TYPE_DEBUG,
1129 "Iterating over set\n");
1130 set->iterator = iter;
1131 set->iterator_cls = iter_cls;
1132 ev = GNUNET_MQ_msg_header (GNUNET_MESSAGE_TYPE_SET_ITER_REQUEST);
1133 GNUNET_MQ_send (set->mq, ev);
1139 GNUNET_SET_copy_lazy (struct GNUNET_SET_Handle *set,
1140 GNUNET_SET_CopyReadyCallback cb,
1143 struct GNUNET_MQ_Envelope *ev;
1144 struct SetCopyRequest *req;
1146 ev = GNUNET_MQ_msg_header (GNUNET_MESSAGE_TYPE_SET_COPY_LAZY_PREPARE);
1147 GNUNET_MQ_send (set->mq, ev);
1149 req = GNUNET_new (struct SetCopyRequest);
1152 GNUNET_CONTAINER_DLL_insert (set->copy_req_head,
1159 * Create a copy of an element. The copy
1160 * must be GNUNET_free-d by the caller.
1162 * @param element the element to copy
1163 * @return the copied element
1165 struct GNUNET_SET_Element *
1166 GNUNET_SET_element_dup (const struct GNUNET_SET_Element *element)
1168 struct GNUNET_SET_Element *copy;
1170 copy = GNUNET_malloc (element->size + sizeof (struct GNUNET_SET_Element));
1171 copy->size = element->size;
1172 copy->element_type = element->element_type;
1173 copy->data = ©[1];
1174 GNUNET_memcpy (©[1],
1182 * Hash a set element.
1184 * @param element the element that should be hashed
1185 * @param[out] ret_hash a pointer to where the hash of @a element
1189 GNUNET_SET_element_hash (const struct GNUNET_SET_Element *element,
1190 struct GNUNET_HashCode *ret_hash)
1192 struct GNUNET_HashContext *ctx = GNUNET_CRYPTO_hash_context_start ();
1194 /* It's not guaranteed that the element data is always after the element header,
1195 so we need to hash the chunks separately. */
1196 GNUNET_CRYPTO_hash_context_read (ctx, &element->size, sizeof (uint16_t));
1197 GNUNET_CRYPTO_hash_context_read (ctx, &element->element_type, sizeof (uint16_t));
1198 GNUNET_CRYPTO_hash_context_read (ctx, element->data, element->size);
1199 GNUNET_CRYPTO_hash_context_finish (ctx, ret_hash);
1202 /* end of set_api.c */