2 This file is part of GNUnet.
3 Copyright (C) 2012-2016 GNUnet e.V.
5 GNUnet is free software: you can redistribute it and/or modify it
6 under the terms of the GNU Affero General Public License as published
7 by the Free Software Foundation, either version 3 of the License,
8 or (at your 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 Affero General Public License for more details.
15 You should have received a copy of the GNU Affero General Public License
16 along with this program. If not, see <http://www.gnu.org/licenses/>.
20 * @brief api for the set service
21 * @author Florian Dold
22 * @author Christian Grothoff
25 #include "gnunet_util_lib.h"
26 #include "gnunet_protocols.h"
27 #include "gnunet_set_service.h"
31 #define LOG(kind,...) GNUNET_log_from (kind, "set-api",__VA_ARGS__)
35 struct SetCopyRequest *next;
37 struct SetCopyRequest *prev;
41 GNUNET_SET_CopyReadyCallback cb;
45 * Opaque handle to a set.
47 struct GNUNET_SET_Handle
50 * Message queue for @e client.
52 struct GNUNET_MQ_Handle *mq;
55 * Linked list of operations on the set.
57 struct GNUNET_SET_OperationHandle *ops_head;
60 * Linked list of operations on the set.
62 struct GNUNET_SET_OperationHandle *ops_tail;
65 * Callback for the current iteration over the set,
66 * NULL if no iterator is active.
68 GNUNET_SET_ElementIterator iterator;
71 * Closure for @e iterator
76 * Should the set be destroyed once all operations are gone?
77 * #GNUNET_SYSERR if #GNUNET_SET_destroy() must raise this flag,
78 * #GNUNET_YES if #GNUNET_SET_destroy() did raise this flag.
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 LOG (GNUNET_ERROR_TYPE_DEBUG,
312 "Received element in set iteration\n");
313 msize = ntohs (msg->header.size);
314 if (set->iteration_id != ntohs (msg->iteration_id))
316 /* element from a previous iteration, skip! */
321 element.size = msize - sizeof (struct GNUNET_SET_IterResponseMessage);
322 element.element_type = ntohs (msg->element_type);
323 element.data = &msg[1];
324 iter (set->iterator_cls,
327 ev = GNUNET_MQ_msg (ack_msg,
328 GNUNET_MESSAGE_TYPE_SET_ITER_ACK);
329 ack_msg->send_more = htonl ((NULL != iter));
330 GNUNET_MQ_send (set->mq, ev);
335 * Handle message signalling conclusion of iteration over the set.
336 * Notifies the iterator that we are done.
339 * @param mh the message
342 handle_iter_done (void *cls,
343 const struct GNUNET_MessageHeader *mh)
345 struct GNUNET_SET_Handle *set = cls;
346 GNUNET_SET_ElementIterator iter = set->iterator;
350 /* FIXME: if this is true, could cancel+start a fresh one
351 cause elements to go to the wrong iteration? */
352 LOG (GNUNET_ERROR_TYPE_INFO,
353 "Service completed set iteration that was already cancelled\n");
356 LOG (GNUNET_ERROR_TYPE_DEBUG,
357 "Set iteration completed\n");
358 set->destroy_requested = GNUNET_SYSERR;
359 set->iterator = NULL;
361 iter (set->iterator_cls,
363 if (GNUNET_SYSERR == set->destroy_requested)
364 set->destroy_requested = GNUNET_NO;
365 if (GNUNET_YES == set->destroy_requested)
366 GNUNET_SET_destroy (set);
371 * Check that the given @a msg is well-formed.
374 * @param msg message to check
375 * @return #GNUNET_OK if message is well-formed
378 check_result (void *cls,
379 const struct GNUNET_SET_ResultMessage *msg)
381 /* minimum size was already checked, everything else is OK! */
387 * Handle result message for a set operation.
390 * @param mh the message
393 handle_result (void *cls,
394 const struct GNUNET_SET_ResultMessage *msg)
396 struct GNUNET_SET_Handle *set = cls;
397 struct GNUNET_SET_OperationHandle *oh;
398 struct GNUNET_SET_Element e;
399 enum GNUNET_SET_Status result_status;
402 GNUNET_assert (NULL != set->mq);
403 result_status = (enum GNUNET_SET_Status) ntohs (msg->result_status);
404 LOG (GNUNET_ERROR_TYPE_DEBUG,
405 "Got result message with status %d\n",
408 oh = GNUNET_MQ_assoc_get (set->mq,
409 ntohl (msg->request_id));
412 /* 'oh' can be NULL if we canceled the operation, but the service
413 did not get the cancel message yet. */
414 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
415 "Ignoring result from canceled operation\n");
419 switch (result_status)
421 case GNUNET_SET_STATUS_OK:
422 case GNUNET_SET_STATUS_ADD_LOCAL:
423 case GNUNET_SET_STATUS_ADD_REMOTE:
425 case GNUNET_SET_STATUS_FAILURE:
426 case GNUNET_SET_STATUS_DONE:
428 case GNUNET_SET_STATUS_HALF_DONE:
429 /* not used anymore */
434 LOG (GNUNET_ERROR_TYPE_DEBUG,
435 "Treating result as final status\n");
436 GNUNET_MQ_assoc_remove (set->mq,
437 ntohl (msg->request_id));
438 GNUNET_CONTAINER_DLL_remove (set->ops_head,
441 /* Need to do this calculation _before_ the result callback,
442 as IF the application still has a valid set handle, it
443 may trigger destruction of the set during the callback. */
444 destroy_set = (GNUNET_YES == set->destroy_requested) &&
445 (NULL == set->ops_head);
446 if (NULL != oh->result_cb)
448 oh->result_cb (oh->result_cls,
450 GNUNET_ntohll (msg->current_size),
455 LOG (GNUNET_ERROR_TYPE_DEBUG,
456 "No callback for final status\n");
459 GNUNET_SET_destroy (set);
464 LOG (GNUNET_ERROR_TYPE_DEBUG,
465 "Treating result as element\n");
467 e.size = ntohs (msg->header.size) - sizeof (struct GNUNET_SET_ResultMessage);
468 e.element_type = ntohs (msg->element_type);
469 if (NULL != oh->result_cb)
470 oh->result_cb (oh->result_cls,
472 GNUNET_ntohll (msg->current_size),
478 * Destroy the given set operation.
480 * @param oh set operation to destroy
483 set_operation_destroy (struct GNUNET_SET_OperationHandle *oh)
485 struct GNUNET_SET_Handle *set = oh->set;
486 struct GNUNET_SET_OperationHandle *h_assoc;
488 if (NULL != oh->conclude_mqm)
489 GNUNET_MQ_discard (oh->conclude_mqm);
490 /* is the operation already commited? */
493 GNUNET_CONTAINER_DLL_remove (set->ops_head,
496 h_assoc = GNUNET_MQ_assoc_remove (set->mq,
498 GNUNET_assert ( (NULL == h_assoc) ||
506 * Cancel the given set operation. We need to send an explicit cancel
507 * message, as all operations one one set communicate using one
510 * @param oh set operation to cancel
513 GNUNET_SET_operation_cancel (struct GNUNET_SET_OperationHandle *oh)
515 struct GNUNET_SET_Handle *set = oh->set;
516 struct GNUNET_SET_CancelMessage *m;
517 struct GNUNET_MQ_Envelope *mqm;
519 LOG (GNUNET_ERROR_TYPE_DEBUG,
520 "Cancelling SET operation\n");
523 mqm = GNUNET_MQ_msg (m, GNUNET_MESSAGE_TYPE_SET_CANCEL);
524 m->request_id = htonl (oh->request_id);
525 GNUNET_MQ_send (set->mq, mqm);
527 set_operation_destroy (oh);
528 if ( (NULL != set) &&
529 (GNUNET_YES == set->destroy_requested) &&
530 (NULL == set->ops_head) )
532 LOG (GNUNET_ERROR_TYPE_DEBUG,
533 "Destroying set after operation cancel\n");
534 GNUNET_SET_destroy (set);
540 * We encountered an error communicating with the set service while
541 * performing a set operation. Report to the application.
543 * @param cls the `struct GNUNET_SET_Handle`
544 * @param error error code
547 handle_client_set_error (void *cls,
548 enum GNUNET_MQ_Error error)
550 struct GNUNET_SET_Handle *set = cls;
551 GNUNET_SET_ElementIterator iter = set->iterator;
553 LOG (GNUNET_ERROR_TYPE_ERROR,
554 "Handling client set error %d\n",
556 while (NULL != set->ops_head)
558 if ( (NULL != set->ops_head->result_cb) &&
559 (GNUNET_NO == set->destroy_requested) )
560 set->ops_head->result_cb (set->ops_head->result_cls,
563 GNUNET_SET_STATUS_FAILURE);
564 set_operation_destroy (set->ops_head);
566 set->iterator = NULL;
568 set->invalid = GNUNET_YES;
570 iter (set->iterator_cls,
578 static struct GNUNET_SET_Handle *
579 create_internal (const struct GNUNET_CONFIGURATION_Handle *cfg,
580 enum GNUNET_SET_OperationType op,
581 const uint32_t *cookie)
583 struct GNUNET_SET_Handle *set = GNUNET_new (struct GNUNET_SET_Handle);
584 struct GNUNET_MQ_MessageHandler mq_handlers[] = {
585 GNUNET_MQ_hd_var_size (result,
586 GNUNET_MESSAGE_TYPE_SET_RESULT,
587 struct GNUNET_SET_ResultMessage,
589 GNUNET_MQ_hd_var_size (iter_element,
590 GNUNET_MESSAGE_TYPE_SET_ITER_ELEMENT,
591 struct GNUNET_SET_IterResponseMessage,
593 GNUNET_MQ_hd_fixed_size (iter_done,
594 GNUNET_MESSAGE_TYPE_SET_ITER_DONE,
595 struct GNUNET_MessageHeader,
597 GNUNET_MQ_hd_fixed_size (copy_lazy,
598 GNUNET_MESSAGE_TYPE_SET_COPY_LAZY_RESPONSE,
599 struct GNUNET_SET_CopyLazyResponseMessage,
601 GNUNET_MQ_handler_end ()
603 struct GNUNET_MQ_Envelope *mqm;
604 struct GNUNET_SET_CreateMessage *create_msg;
605 struct GNUNET_SET_CopyLazyConnectMessage *copy_msg;
608 set->mq = GNUNET_CLIENT_connect (cfg,
611 &handle_client_set_error,
620 LOG (GNUNET_ERROR_TYPE_DEBUG,
621 "Creating new set (operation %u)\n",
623 mqm = GNUNET_MQ_msg (create_msg,
624 GNUNET_MESSAGE_TYPE_SET_CREATE);
625 create_msg->operation = htonl (op);
629 LOG (GNUNET_ERROR_TYPE_DEBUG,
630 "Creating new set (lazy copy)\n",
632 mqm = GNUNET_MQ_msg (copy_msg,
633 GNUNET_MESSAGE_TYPE_SET_COPY_LAZY_CONNECT);
634 copy_msg->cookie = *cookie;
636 GNUNET_MQ_send (set->mq,
643 * Create an empty set, supporting the specified operation.
645 * @param cfg configuration to use for connecting to the
647 * @param op operation supported by the set
648 * Note that the operation has to be specified
649 * beforehand, as certain set operations need to maintain
650 * data structures spefific to the operation
651 * @return a handle to the set
653 struct GNUNET_SET_Handle *
654 GNUNET_SET_create (const struct GNUNET_CONFIGURATION_Handle *cfg,
655 enum GNUNET_SET_OperationType op)
657 struct GNUNET_SET_Handle *set;
659 set = create_internal (cfg,
662 LOG (GNUNET_ERROR_TYPE_DEBUG,
663 "Creating set %p for operation %d\n",
671 * Add an element to the given set. After the element has been added
672 * (in the sense of being transmitted to the set service), @a cont
673 * will be called. Multiple calls to GNUNET_SET_add_element() can be
676 * @param set set to add element to
677 * @param element element to add to the set
678 * @param cont continuation called after the element has been added
679 * @param cont_cls closure for @a cont
680 * @return #GNUNET_OK on success, #GNUNET_SYSERR if the
681 * set is invalid (e.g. the set service crashed)
684 GNUNET_SET_add_element (struct GNUNET_SET_Handle *set,
685 const struct GNUNET_SET_Element *element,
686 GNUNET_SET_Continuation cont,
689 struct GNUNET_MQ_Envelope *mqm;
690 struct GNUNET_SET_ElementMessage *msg;
692 LOG (GNUNET_ERROR_TYPE_DEBUG,
693 "adding element of type %u to set %p\n",
694 (unsigned int) element->element_type,
696 GNUNET_assert (NULL != set);
697 if (GNUNET_YES == set->invalid)
701 return GNUNET_SYSERR;
703 mqm = GNUNET_MQ_msg_extra (msg,
705 GNUNET_MESSAGE_TYPE_SET_ADD);
706 msg->element_type = htons (element->element_type);
707 GNUNET_memcpy (&msg[1],
710 GNUNET_MQ_notify_sent (mqm,
712 GNUNET_MQ_send (set->mq, mqm);
718 * Remove an element to the given set. After the element has been
719 * removed (in the sense of the request being transmitted to the set
720 * service), @a cont will be called. Multiple calls to
721 * GNUNET_SET_remove_element() can be queued
723 * @param set set to remove element from
724 * @param element element to remove from the set
725 * @param cont continuation called after the element has been removed
726 * @param cont_cls closure for @a cont
727 * @return #GNUNET_OK on success, #GNUNET_SYSERR if the
728 * set is invalid (e.g. the set service crashed)
731 GNUNET_SET_remove_element (struct GNUNET_SET_Handle *set,
732 const struct GNUNET_SET_Element *element,
733 GNUNET_SET_Continuation cont,
736 struct GNUNET_MQ_Envelope *mqm;
737 struct GNUNET_SET_ElementMessage *msg;
739 LOG (GNUNET_ERROR_TYPE_DEBUG,
740 "Removing element from set %p\n",
742 if (GNUNET_YES == set->invalid)
746 return GNUNET_SYSERR;
748 mqm = GNUNET_MQ_msg_extra (msg,
750 GNUNET_MESSAGE_TYPE_SET_REMOVE);
751 msg->element_type = htons (element->element_type);
752 GNUNET_memcpy (&msg[1],
755 GNUNET_MQ_notify_sent (mqm,
757 GNUNET_MQ_send (set->mq, mqm);
763 * Destroy the set handle if no operations are left, mark the set
764 * for destruction otherwise.
766 * @param set set handle to destroy
769 GNUNET_SET_destroy (struct GNUNET_SET_Handle *set)
771 /* destroying set while iterator is active is currently
772 not supported; we should expand the API to allow
773 clients to explicitly cancel the iteration! */
774 GNUNET_assert (NULL != set);
775 if ( (NULL != set->ops_head) ||
776 (NULL != set->iterator) ||
777 (GNUNET_SYSERR == set->destroy_requested) )
779 LOG (GNUNET_ERROR_TYPE_DEBUG,
780 "Set operations are pending, delaying set destruction\n");
781 set->destroy_requested = GNUNET_YES;
784 LOG (GNUNET_ERROR_TYPE_DEBUG,
785 "Really destroying set\n");
788 GNUNET_MQ_destroy (set->mq);
796 * Prepare a set operation to be evaluated with another peer.
797 * The evaluation will not start until the client provides
798 * a local set with #GNUNET_SET_commit().
800 * @param other_peer peer with the other set
801 * @param app_id hash for the application using the set
802 * @param context_msg additional information for the request
803 * @param result_mode specified how results will be returned,
804 * see `enum GNUNET_SET_ResultMode`.
805 * @param result_cb called on error or success
806 * @param result_cls closure for @e result_cb
807 * @return a handle to cancel the operation
809 struct GNUNET_SET_OperationHandle *
810 GNUNET_SET_prepare (const struct GNUNET_PeerIdentity *other_peer,
811 const struct GNUNET_HashCode *app_id,
812 const struct GNUNET_MessageHeader *context_msg,
813 enum GNUNET_SET_ResultMode result_mode,
814 struct GNUNET_SET_Option options[],
815 GNUNET_SET_ResultIterator result_cb,
818 struct GNUNET_MQ_Envelope *mqm;
819 struct GNUNET_SET_OperationHandle *oh;
820 struct GNUNET_SET_EvaluateMessage *msg;
821 struct GNUNET_SET_Option *opt;
823 LOG (GNUNET_ERROR_TYPE_DEBUG,
824 "Client prepares set operation (%d)\n",
826 oh = GNUNET_new (struct GNUNET_SET_OperationHandle);
827 oh->result_cb = result_cb;
828 oh->result_cls = result_cls;
829 mqm = GNUNET_MQ_msg_nested_mh (msg,
830 GNUNET_MESSAGE_TYPE_SET_EVALUATE,
832 msg->app_id = *app_id;
833 msg->result_mode = htonl (result_mode);
834 msg->target_peer = *other_peer;
835 for (opt = options; opt->type != 0; opt++)
839 case GNUNET_SET_OPTION_BYZANTINE:
840 msg->byzantine = GNUNET_YES;
841 msg->byzantine_lower_bound = opt->v.num;
843 case GNUNET_SET_OPTION_FORCE_FULL:
844 msg->force_full = GNUNET_YES;
846 case GNUNET_SET_OPTION_FORCE_DELTA:
847 msg->force_delta = GNUNET_YES;
850 LOG (GNUNET_ERROR_TYPE_ERROR,
851 "Option with type %d not recognized\n", (int) opt->type);
854 oh->conclude_mqm = mqm;
855 oh->request_id_addr = &msg->request_id;
862 * Connect to the set service in order to listen for requests.
864 * @param cls the `struct GNUNET_SET_ListenHandle *` to connect
867 listen_connect (void *cls);
871 * Check validity of request message for a listen operation
873 * @param cls the listen handle
874 * @param msg the message
875 * @return #GNUNET_OK if the message is well-formed
878 check_request (void *cls,
879 const struct GNUNET_SET_RequestMessage *msg)
881 const struct GNUNET_MessageHeader *context_msg;
883 if (ntohs (msg->header.size) == sizeof (*msg))
884 return GNUNET_OK; /* no context message is OK */
885 context_msg = GNUNET_MQ_extract_nested_mh (msg);
886 if (NULL == context_msg)
888 /* malformed context message is NOT ok */
890 return GNUNET_SYSERR;
897 * Handle request message for a listen operation
899 * @param cls the listen handle
900 * @param msg the message
903 handle_request (void *cls,
904 const struct GNUNET_SET_RequestMessage *msg)
906 struct GNUNET_SET_ListenHandle *lh = cls;
907 struct GNUNET_SET_Request req;
908 const struct GNUNET_MessageHeader *context_msg;
909 struct GNUNET_MQ_Envelope *mqm;
910 struct GNUNET_SET_RejectMessage *rmsg;
912 LOG (GNUNET_ERROR_TYPE_DEBUG,
913 "Processing incoming operation request with id %u\n",
914 ntohl (msg->accept_id));
915 /* we got another valid request => reset the backoff */
916 lh->reconnect_backoff = GNUNET_TIME_UNIT_MILLISECONDS;
917 req.accept_id = ntohl (msg->accept_id);
918 req.accepted = GNUNET_NO;
919 context_msg = GNUNET_MQ_extract_nested_mh (msg);
920 /* calling #GNUNET_SET_accept() in the listen cb will set req->accepted */
921 lh->listen_cb (lh->listen_cls,
925 if (GNUNET_YES == req.accepted)
926 return; /* the accept-case is handled in #GNUNET_SET_accept() */
927 LOG (GNUNET_ERROR_TYPE_DEBUG,
928 "Rejected request %u\n",
929 ntohl (msg->accept_id));
930 mqm = GNUNET_MQ_msg (rmsg,
931 GNUNET_MESSAGE_TYPE_SET_REJECT);
932 rmsg->accept_reject_id = msg->accept_id;
933 GNUNET_MQ_send (lh->mq, mqm);
938 * Our connection with the set service encountered an error,
939 * re-initialize with exponential back-off.
941 * @param cls the `struct GNUNET_SET_ListenHandle *`
942 * @param error reason for the disconnect
945 handle_client_listener_error (void *cls,
946 enum GNUNET_MQ_Error error)
948 struct GNUNET_SET_ListenHandle *lh = cls;
950 LOG (GNUNET_ERROR_TYPE_DEBUG,
951 "Listener broke down (%d), re-connecting\n",
953 GNUNET_MQ_destroy (lh->mq);
955 lh->reconnect_task = GNUNET_SCHEDULER_add_delayed (lh->reconnect_backoff,
958 lh->reconnect_backoff = GNUNET_TIME_STD_BACKOFF (lh->reconnect_backoff);
963 * Connect to the set service in order to listen for requests.
965 * @param cls the `struct GNUNET_SET_ListenHandle *` to connect
968 listen_connect (void *cls)
970 struct GNUNET_SET_ListenHandle *lh = cls;
971 struct GNUNET_MQ_MessageHandler mq_handlers[] = {
972 GNUNET_MQ_hd_var_size (request,
973 GNUNET_MESSAGE_TYPE_SET_REQUEST,
974 struct GNUNET_SET_RequestMessage,
976 GNUNET_MQ_handler_end ()
978 struct GNUNET_MQ_Envelope *mqm;
979 struct GNUNET_SET_ListenMessage *msg;
981 lh->reconnect_task = NULL;
982 GNUNET_assert (NULL == lh->mq);
983 lh->mq = GNUNET_CLIENT_connect (lh->cfg,
986 &handle_client_listener_error,
990 mqm = GNUNET_MQ_msg (msg, GNUNET_MESSAGE_TYPE_SET_LISTEN);
991 msg->operation = htonl (lh->operation);
992 msg->app_id = lh->app_id;
993 GNUNET_MQ_send (lh->mq,
999 * Wait for set operation requests for the given application id
1001 * @param cfg configuration to use for connecting to
1002 * the set service, needs to be valid for the lifetime of the listen handle
1003 * @param operation operation we want to listen for
1004 * @param app_id id of the application that handles set operation requests
1005 * @param listen_cb called for each incoming request matching the operation
1006 * and application id
1007 * @param listen_cls handle for @a listen_cb
1008 * @return a handle that can be used to cancel the listen operation
1010 struct GNUNET_SET_ListenHandle *
1011 GNUNET_SET_listen (const struct GNUNET_CONFIGURATION_Handle *cfg,
1012 enum GNUNET_SET_OperationType operation,
1013 const struct GNUNET_HashCode *app_id,
1014 GNUNET_SET_ListenCallback listen_cb,
1017 struct GNUNET_SET_ListenHandle *lh;
1019 LOG (GNUNET_ERROR_TYPE_DEBUG,
1020 "Starting listener for app %s\n",
1021 GNUNET_h2s (app_id));
1022 lh = GNUNET_new (struct GNUNET_SET_ListenHandle);
1023 lh->listen_cb = listen_cb;
1024 lh->listen_cls = listen_cls;
1026 lh->operation = operation;
1027 lh->app_id = *app_id;
1028 lh->reconnect_backoff = GNUNET_TIME_UNIT_MILLISECONDS;
1029 listen_connect (lh);
1040 * Cancel the given listen operation.
1042 * @param lh handle for the listen operation
1045 GNUNET_SET_listen_cancel (struct GNUNET_SET_ListenHandle *lh)
1047 LOG (GNUNET_ERROR_TYPE_DEBUG,
1048 "Canceling listener %s\n",
1049 GNUNET_h2s (&lh->app_id));
1052 GNUNET_MQ_destroy (lh->mq);
1055 if (NULL != lh->reconnect_task)
1057 GNUNET_SCHEDULER_cancel (lh->reconnect_task);
1058 lh->reconnect_task = NULL;
1065 * Accept a request we got via #GNUNET_SET_listen. Must be called during
1066 * #GNUNET_SET_listen, as the 'struct GNUNET_SET_Request' becomes invalid
1068 * Call #GNUNET_SET_commit to provide the local set to use for the operation,
1069 * and to begin the exchange with the remote peer.
1071 * @param request request to accept
1072 * @param result_mode specified how results will be returned,
1073 * see `enum GNUNET_SET_ResultMode`.
1074 * @param result_cb callback for the results
1075 * @param result_cls closure for @a result_cb
1076 * @return a handle to cancel the operation
1078 struct GNUNET_SET_OperationHandle *
1079 GNUNET_SET_accept (struct GNUNET_SET_Request *request,
1080 enum GNUNET_SET_ResultMode result_mode,
1081 struct GNUNET_SET_Option options[],
1082 GNUNET_SET_ResultIterator result_cb,
1085 struct GNUNET_MQ_Envelope *mqm;
1086 struct GNUNET_SET_OperationHandle *oh;
1087 struct GNUNET_SET_AcceptMessage *msg;
1089 GNUNET_assert (GNUNET_NO == request->accepted);
1090 LOG (GNUNET_ERROR_TYPE_DEBUG,
1091 "Client accepts set operation (%d) with id %u\n",
1093 request->accept_id);
1094 request->accepted = GNUNET_YES;
1095 mqm = GNUNET_MQ_msg (msg,
1096 GNUNET_MESSAGE_TYPE_SET_ACCEPT);
1097 msg->accept_reject_id = htonl (request->accept_id);
1098 msg->result_mode = htonl (result_mode);
1099 oh = GNUNET_new (struct GNUNET_SET_OperationHandle);
1100 oh->result_cb = result_cb;
1101 oh->result_cls = result_cls;
1102 oh->conclude_mqm = mqm;
1103 oh->request_id_addr = &msg->request_id;
1109 * Commit a set to be used with a set operation.
1110 * This function is called once we have fully constructed
1111 * the set that we want to use for the operation. At this
1112 * time, the P2P protocol can then begin to exchange the
1113 * set information and call the result callback with the
1114 * result information.
1116 * @param oh handle to the set operation
1117 * @param set the set to use for the operation
1118 * @return #GNUNET_OK on success, #GNUNET_SYSERR if the
1119 * set is invalid (e.g. the set service crashed)
1122 GNUNET_SET_commit (struct GNUNET_SET_OperationHandle *oh,
1123 struct GNUNET_SET_Handle *set)
1125 if (NULL != oh->set)
1127 /* Some other set was already committed for this
1128 * operation, there is a logic bug in the client of this API */
1132 GNUNET_assert (NULL != set);
1133 if (GNUNET_YES == set->invalid)
1134 return GNUNET_SYSERR;
1135 LOG (GNUNET_ERROR_TYPE_DEBUG,
1136 "Client commits to SET\n");
1137 GNUNET_assert (NULL != oh->conclude_mqm);
1139 GNUNET_CONTAINER_DLL_insert (set->ops_head,
1142 oh->request_id = GNUNET_MQ_assoc_add (set->mq,
1144 *oh->request_id_addr = htonl (oh->request_id);
1145 GNUNET_MQ_send (set->mq,
1147 oh->conclude_mqm = NULL;
1148 oh->request_id_addr = NULL;
1154 * Iterate over all elements in the given set. Note that this
1155 * operation involves transferring every element of the set from the
1156 * service to the client, and is thus costly.
1158 * @param set the set to iterate over
1159 * @param iter the iterator to call for each element
1160 * @param iter_cls closure for @a iter
1161 * @return #GNUNET_YES if the iteration started successfuly,
1162 * #GNUNET_NO if another iteration is active
1163 * #GNUNET_SYSERR if the set is invalid (e.g. the server crashed, disconnected)
1166 GNUNET_SET_iterate (struct GNUNET_SET_Handle *set,
1167 GNUNET_SET_ElementIterator iter,
1170 struct GNUNET_MQ_Envelope *ev;
1172 GNUNET_assert (NULL != iter);
1173 if (GNUNET_YES == set->invalid)
1174 return GNUNET_SYSERR;
1175 if (NULL != set->iterator)
1177 LOG (GNUNET_ERROR_TYPE_DEBUG,
1178 "Iterating over set\n");
1179 set->iterator = iter;
1180 set->iterator_cls = iter_cls;
1181 ev = GNUNET_MQ_msg_header (GNUNET_MESSAGE_TYPE_SET_ITER_REQUEST);
1182 GNUNET_MQ_send (set->mq, ev);
1188 GNUNET_SET_copy_lazy (struct GNUNET_SET_Handle *set,
1189 GNUNET_SET_CopyReadyCallback cb,
1192 struct GNUNET_MQ_Envelope *ev;
1193 struct SetCopyRequest *req;
1195 LOG (GNUNET_ERROR_TYPE_DEBUG,
1196 "Creating lazy copy of set\n");
1197 ev = GNUNET_MQ_msg_header (GNUNET_MESSAGE_TYPE_SET_COPY_LAZY_PREPARE);
1198 GNUNET_MQ_send (set->mq, ev);
1200 req = GNUNET_new (struct SetCopyRequest);
1203 GNUNET_CONTAINER_DLL_insert (set->copy_req_head,
1210 * Create a copy of an element. The copy
1211 * must be GNUNET_free-d by the caller.
1213 * @param element the element to copy
1214 * @return the copied element
1216 struct GNUNET_SET_Element *
1217 GNUNET_SET_element_dup (const struct GNUNET_SET_Element *element)
1219 struct GNUNET_SET_Element *copy;
1221 copy = GNUNET_malloc (element->size + sizeof (struct GNUNET_SET_Element));
1222 copy->size = element->size;
1223 copy->element_type = element->element_type;
1224 copy->data = ©[1];
1225 GNUNET_memcpy (©[1],
1233 * Hash a set element.
1235 * @param element the element that should be hashed
1236 * @param[out] ret_hash a pointer to where the hash of @a element
1240 GNUNET_SET_element_hash (const struct GNUNET_SET_Element *element,
1241 struct GNUNET_HashCode *ret_hash)
1243 struct GNUNET_HashContext *ctx = GNUNET_CRYPTO_hash_context_start ();
1245 /* It's not guaranteed that the element data is always after the element header,
1246 so we need to hash the chunks separately. */
1247 GNUNET_CRYPTO_hash_context_read (ctx, &element->size, sizeof (uint16_t));
1248 GNUNET_CRYPTO_hash_context_read (ctx, &element->element_type, sizeof (uint16_t));
1249 GNUNET_CRYPTO_hash_context_read (ctx, element->data, element->size);
1250 GNUNET_CRYPTO_hash_context_finish (ctx, ret_hash);
1253 /* end of set_api.c */