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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,
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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,
246 const uint32_t *cookie);
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 msg the message
257 handle_copy_lazy (void *cls,
258 const struct GNUNET_SET_CopyLazyResponseMessage *msg)
260 struct GNUNET_SET_Handle *set = cls;
261 struct SetCopyRequest *req;
262 struct GNUNET_SET_Handle *new_set;
264 req = set->copy_req_head;
267 /* Service sent us unsolicited lazy copy response */
272 LOG (GNUNET_ERROR_TYPE_DEBUG,
273 "Handling response to lazy copy\n");
274 GNUNET_CONTAINER_DLL_remove (set->copy_req_head,
277 // We pass none as operation here, since it doesn't matter when
279 new_set = create_internal (set->cfg,
280 GNUNET_SET_OPERATION_NONE,
282 req->cb (req->cls, new_set);
288 * Check that the given @a msg is well-formed.
291 * @param msg message to check
292 * @return #GNUNET_OK if message is well-formed
295 check_iter_element (void *cls,
296 const struct GNUNET_SET_IterResponseMessage *msg)
298 /* minimum size was already checked, everything else is OK! */
304 * Handle element for iteration over the set. Notifies the
305 * iterator and sends an acknowledgement to the service.
307 * @param cls the `struct GNUNET_SET_Handle *`
308 * @param mh the message
311 handle_iter_element (void *cls,
312 const struct GNUNET_SET_IterResponseMessage *msg)
314 struct GNUNET_SET_Handle *set = cls;
315 GNUNET_SET_ElementIterator iter = set->iterator;
316 struct GNUNET_SET_Element element;
317 struct GNUNET_SET_IterAckMessage *ack_msg;
318 struct GNUNET_MQ_Envelope *ev;
321 msize = ntohs (msg->header.size);
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 = ntohs (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 * Check that the given @a msg is well-formed.
369 * @param msg message to check
370 * @return #GNUNET_OK if message is well-formed
373 check_result (void *cls,
374 const struct GNUNET_SET_ResultMessage *msg)
376 /* minimum size was already checked, everything else is OK! */
382 * Handle result message for a set operation.
385 * @param mh the message
388 handle_result (void *cls,
389 const struct GNUNET_SET_ResultMessage *msg)
391 struct GNUNET_SET_Handle *set = cls;
392 struct GNUNET_SET_OperationHandle *oh;
393 struct GNUNET_SET_Element e;
394 enum GNUNET_SET_Status result_status;
396 GNUNET_assert (NULL != set->mq);
397 result_status = ntohs (msg->result_status);
398 LOG (GNUNET_ERROR_TYPE_DEBUG,
399 "Got result message with status %d\n",
402 oh = GNUNET_MQ_assoc_get (set->mq,
403 ntohl (msg->request_id));
406 /* 'oh' can be NULL if we canceled the operation, but the service
407 did not get the cancel message yet. */
408 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
409 "Ignoring result from canceled operation\n");
413 switch (result_status)
415 case GNUNET_SET_STATUS_OK:
416 case GNUNET_SET_STATUS_ADD_LOCAL:
417 case GNUNET_SET_STATUS_ADD_REMOTE:
419 case GNUNET_SET_STATUS_FAILURE:
420 case GNUNET_SET_STATUS_DONE:
422 case GNUNET_SET_STATUS_HALF_DONE:
423 /* not used anymore */
428 LOG (GNUNET_ERROR_TYPE_DEBUG,
429 "Treating result as final status\n");
430 GNUNET_MQ_assoc_remove (set->mq,
431 ntohl (msg->request_id));
432 GNUNET_CONTAINER_DLL_remove (set->ops_head,
435 if (NULL != oh->result_cb)
437 oh->result_cb (oh->result_cls,
443 LOG (GNUNET_ERROR_TYPE_DEBUG,
444 "No callback for final status\n");
446 if ( (GNUNET_YES == set->destroy_requested) &&
447 (NULL == set->ops_head) )
448 GNUNET_SET_destroy (set);
453 LOG (GNUNET_ERROR_TYPE_DEBUG,
454 "Treating result as element\n");
456 e.size = ntohs (msg->header.size) - sizeof (struct GNUNET_SET_ResultMessage);
457 e.element_type = ntohs (msg->element_type);
458 if (NULL != oh->result_cb)
459 oh->result_cb (oh->result_cls,
466 * Destroy the given set operation.
468 * @param oh set operation to destroy
471 set_operation_destroy (struct GNUNET_SET_OperationHandle *oh)
473 struct GNUNET_SET_Handle *set = oh->set;
474 struct GNUNET_SET_OperationHandle *h_assoc;
476 if (NULL != oh->conclude_mqm)
477 GNUNET_MQ_discard (oh->conclude_mqm);
478 /* is the operation already commited? */
481 GNUNET_CONTAINER_DLL_remove (set->ops_head,
484 h_assoc = GNUNET_MQ_assoc_remove (set->mq,
486 GNUNET_assert ((NULL == h_assoc) || (h_assoc == oh));
493 * Cancel the given set operation. We need to send an explicit cancel
494 * message, as all operations one one set communicate using one
497 * @param oh set operation to cancel
500 GNUNET_SET_operation_cancel (struct GNUNET_SET_OperationHandle *oh)
502 struct GNUNET_SET_Handle *set = oh->set;
503 struct GNUNET_SET_CancelMessage *m;
504 struct GNUNET_MQ_Envelope *mqm;
508 mqm = GNUNET_MQ_msg (m, GNUNET_MESSAGE_TYPE_SET_CANCEL);
509 m->request_id = htonl (oh->request_id);
510 GNUNET_MQ_send (set->mq, mqm);
512 set_operation_destroy (oh);
513 if ( (NULL != set) &&
514 (GNUNET_YES == set->destroy_requested) &&
515 (NULL == set->ops_head) )
517 LOG (GNUNET_ERROR_TYPE_DEBUG,
518 "Destroying set after operation cancel\n");
519 GNUNET_SET_destroy (set);
525 * We encountered an error communicating with the set service while
526 * performing a set operation. Report to the application.
528 * @param cls the `struct GNUNET_SET_Handle`
529 * @param error error code
532 handle_client_set_error (void *cls,
533 enum GNUNET_MQ_Error error)
535 struct GNUNET_SET_Handle *set = cls;
536 GNUNET_SET_ElementIterator iter = set->iterator;
538 LOG (GNUNET_ERROR_TYPE_DEBUG,
539 "Handling client set error %d\n",
541 while (NULL != set->ops_head)
543 if (NULL != set->ops_head->result_cb)
544 set->ops_head->result_cb (set->ops_head->result_cls,
546 GNUNET_SET_STATUS_FAILURE);
547 set_operation_destroy (set->ops_head);
549 set->iterator = NULL;
552 iter (set->iterator_cls,
554 set->invalid = GNUNET_YES;
555 if (GNUNET_YES == set->destroy_requested)
557 LOG (GNUNET_ERROR_TYPE_DEBUG,
558 "Destroying set after operation failure\n");
559 GNUNET_SET_destroy (set);
564 static struct GNUNET_SET_Handle *
565 create_internal (const struct GNUNET_CONFIGURATION_Handle *cfg,
566 enum GNUNET_SET_OperationType op,
567 const uint32_t *cookie)
569 GNUNET_MQ_hd_var_size (result,
570 GNUNET_MESSAGE_TYPE_SET_RESULT,
571 struct GNUNET_SET_ResultMessage);
572 GNUNET_MQ_hd_var_size (iter_element,
573 GNUNET_MESSAGE_TYPE_SET_ITER_ELEMENT,
574 struct GNUNET_SET_IterResponseMessage);
575 GNUNET_MQ_hd_fixed_size (iter_done,
576 GNUNET_MESSAGE_TYPE_SET_ITER_DONE,
577 struct GNUNET_MessageHeader);
578 GNUNET_MQ_hd_fixed_size (copy_lazy,
579 GNUNET_MESSAGE_TYPE_SET_COPY_LAZY_RESPONSE,
580 struct GNUNET_SET_CopyLazyResponseMessage);
581 struct GNUNET_SET_Handle *set = GNUNET_new (struct GNUNET_SET_Handle);
582 struct GNUNET_MQ_MessageHandler mq_handlers[] = {
583 make_result_handler (set),
584 make_iter_element_handler (set),
585 make_iter_done_handler (set),
586 make_copy_lazy_handler (set),
587 GNUNET_MQ_handler_end ()
589 struct GNUNET_MQ_Envelope *mqm;
590 struct GNUNET_SET_CreateMessage *create_msg;
591 struct GNUNET_SET_CopyLazyConnectMessage *copy_msg;
594 set->client = GNUNET_CLIENT_connect ("set", cfg);
595 if (NULL == set->client)
600 set->mq = GNUNET_MQ_queue_for_connection_client (set->client,
602 &handle_client_set_error,
604 GNUNET_assert (NULL != set->mq);
608 LOG (GNUNET_ERROR_TYPE_DEBUG,
609 "Creating new set (operation %u)\n",
611 mqm = GNUNET_MQ_msg (create_msg,
612 GNUNET_MESSAGE_TYPE_SET_CREATE);
613 create_msg->operation = htonl (op);
617 LOG (GNUNET_ERROR_TYPE_DEBUG,
618 "Creating new set (lazy copy)\n",
620 mqm = GNUNET_MQ_msg (copy_msg,
621 GNUNET_MESSAGE_TYPE_SET_COPY_LAZY_CONNECT);
622 copy_msg->cookie = *cookie;
624 GNUNET_MQ_send (set->mq, mqm);
630 * Create an empty set, supporting the specified operation.
632 * @param cfg configuration to use for connecting to the
634 * @param op operation supported by the set
635 * Note that the operation has to be specified
636 * beforehand, as certain set operations need to maintain
637 * data structures spefific to the operation
638 * @return a handle to the set
640 struct GNUNET_SET_Handle *
641 GNUNET_SET_create (const struct GNUNET_CONFIGURATION_Handle *cfg,
642 enum GNUNET_SET_OperationType op)
644 return create_internal (cfg, op, NULL);
649 * Add an element to the given set. After the element has been added
650 * (in the sense of being transmitted to the set service), @a cont
651 * will be called. Multiple calls to GNUNET_SET_add_element() can be
654 * @param set set to add element to
655 * @param element element to add to the set
656 * @param cont continuation called after the element has been added
657 * @param cont_cls closure for @a cont
658 * @return #GNUNET_OK on success, #GNUNET_SYSERR if the
659 * set is invalid (e.g. the set service crashed)
662 GNUNET_SET_add_element (struct GNUNET_SET_Handle *set,
663 const struct GNUNET_SET_Element *element,
664 GNUNET_SET_Continuation cont,
667 struct GNUNET_MQ_Envelope *mqm;
668 struct GNUNET_SET_ElementMessage *msg;
670 if (GNUNET_YES == set->invalid)
674 return GNUNET_SYSERR;
676 mqm = GNUNET_MQ_msg_extra (msg, element->size,
677 GNUNET_MESSAGE_TYPE_SET_ADD);
678 msg->element_type = htons (element->element_type);
682 GNUNET_MQ_notify_sent (mqm,
684 GNUNET_MQ_send (set->mq, mqm);
690 * Remove an element to the given set. After the element has been
691 * removed (in the sense of the request being transmitted to the set
692 * service), @a cont will be called. Multiple calls to
693 * GNUNET_SET_remove_element() can be queued
695 * @param set set to remove element from
696 * @param element element to remove from the set
697 * @param cont continuation called after the element has been removed
698 * @param cont_cls closure for @a cont
699 * @return #GNUNET_OK on success, #GNUNET_SYSERR if the
700 * set is invalid (e.g. the set service crashed)
703 GNUNET_SET_remove_element (struct GNUNET_SET_Handle *set,
704 const struct GNUNET_SET_Element *element,
705 GNUNET_SET_Continuation cont,
708 struct GNUNET_MQ_Envelope *mqm;
709 struct GNUNET_SET_ElementMessage *msg;
711 if (GNUNET_YES == set->invalid)
715 return GNUNET_SYSERR;
717 mqm = GNUNET_MQ_msg_extra (msg,
719 GNUNET_MESSAGE_TYPE_SET_REMOVE);
720 msg->element_type = htons (element->element_type);
724 GNUNET_MQ_notify_sent (mqm,
726 GNUNET_MQ_send (set->mq, mqm);
732 * Destroy the set handle if no operations are left, mark the set
733 * for destruction otherwise.
735 * @param set set handle to destroy
738 GNUNET_SET_destroy (struct GNUNET_SET_Handle *set)
740 /* destroying set while iterator is active is currently
741 not supported; we should expand the API to allow
742 clients to explicitly cancel the iteration! */
743 GNUNET_assert (NULL == set->iterator);
744 if (NULL != set->ops_head)
746 LOG (GNUNET_ERROR_TYPE_DEBUG,
747 "Set operations are pending, delaying set destruction\n");
748 set->destroy_requested = GNUNET_YES;
751 LOG (GNUNET_ERROR_TYPE_DEBUG,
752 "Really destroying set\n");
753 if (NULL != set->client)
755 GNUNET_CLIENT_disconnect (set->client);
760 GNUNET_MQ_destroy (set->mq);
768 * Prepare a set operation to be evaluated with another peer.
769 * The evaluation will not start until the client provides
770 * a local set with #GNUNET_SET_commit().
772 * @param other_peer peer with the other set
773 * @param app_id hash for the application using the set
774 * @param context_msg additional information for the request
775 * @param result_mode specified how results will be returned,
776 * see `enum GNUNET_SET_ResultMode`.
777 * @param result_cb called on error or success
778 * @param result_cls closure for @e result_cb
779 * @return a handle to cancel the operation
781 struct GNUNET_SET_OperationHandle *
782 GNUNET_SET_prepare (const struct GNUNET_PeerIdentity *other_peer,
783 const struct GNUNET_HashCode *app_id,
784 const struct GNUNET_MessageHeader *context_msg,
785 enum GNUNET_SET_ResultMode result_mode,
786 GNUNET_SET_ResultIterator result_cb,
789 struct GNUNET_MQ_Envelope *mqm;
790 struct GNUNET_SET_OperationHandle *oh;
791 struct GNUNET_SET_EvaluateMessage *msg;
793 oh = GNUNET_new (struct GNUNET_SET_OperationHandle);
794 oh->result_cb = result_cb;
795 oh->result_cls = result_cls;
796 mqm = GNUNET_MQ_msg_nested_mh (msg,
797 GNUNET_MESSAGE_TYPE_SET_EVALUATE,
799 msg->app_id = *app_id;
800 msg->result_mode = htonl (result_mode);
801 msg->target_peer = *other_peer;
802 oh->conclude_mqm = mqm;
803 oh->request_id_addr = &msg->request_id;
810 * Connect to the set service in order to listen for requests.
812 * @param cls the `struct GNUNET_SET_ListenHandle *` to connect
815 listen_connect (void *cls);
819 * Check validity of request message for a listen operation
821 * @param cls the listen handle
822 * @param msg the message
823 * @return #GNUNET_OK if the message is well-formed
826 check_request (void *cls,
827 const struct GNUNET_SET_RequestMessage *msg)
829 const struct GNUNET_MessageHeader *context_msg;
831 context_msg = GNUNET_MQ_extract_nested_mh (msg);
832 if (NULL == context_msg)
835 return GNUNET_SYSERR;
842 * Handle request message for a listen operation
844 * @param cls the listen handle
845 * @param msg the message
848 handle_request (void *cls,
849 const struct GNUNET_SET_RequestMessage *msg)
851 struct GNUNET_SET_ListenHandle *lh = cls;
852 struct GNUNET_SET_Request req;
853 const struct GNUNET_MessageHeader *context_msg;
854 struct GNUNET_MQ_Envelope *mqm;
855 struct GNUNET_SET_RejectMessage *rmsg;
857 LOG (GNUNET_ERROR_TYPE_DEBUG,
858 "Processing incoming operation request\n");
859 /* we got another valid request => reset the backoff */
860 lh->reconnect_backoff = GNUNET_TIME_UNIT_MILLISECONDS;
861 req.accept_id = ntohl (msg->accept_id);
862 req.accepted = GNUNET_NO;
863 context_msg = GNUNET_MQ_extract_nested_mh (msg);
864 /* calling #GNUNET_SET_accept() in the listen cb will set req->accepted */
865 lh->listen_cb (lh->listen_cls,
869 if (GNUNET_YES == req.accepted)
870 return; /* the accept-case is handled in #GNUNET_SET_accept() */
871 LOG (GNUNET_ERROR_TYPE_DEBUG,
872 "Rejecting request\n");
873 mqm = GNUNET_MQ_msg (rmsg,
874 GNUNET_MESSAGE_TYPE_SET_REJECT);
875 rmsg->accept_reject_id = msg->accept_id;
876 GNUNET_MQ_send (lh->mq, mqm);
881 * Our connection with the set service encountered an error,
882 * re-initialize with exponential back-off.
884 * @param cls the `struct GNUNET_SET_ListenHandle *`
885 * @param error reason for the disconnect
888 handle_client_listener_error (void *cls,
889 enum GNUNET_MQ_Error error)
891 struct GNUNET_SET_ListenHandle *lh = cls;
893 LOG (GNUNET_ERROR_TYPE_DEBUG,
894 "Listener broke down (%d), re-connecting\n",
896 GNUNET_CLIENT_disconnect (lh->client);
898 GNUNET_MQ_destroy (lh->mq);
900 lh->reconnect_task = GNUNET_SCHEDULER_add_delayed (lh->reconnect_backoff,
903 lh->reconnect_backoff = GNUNET_TIME_STD_BACKOFF (lh->reconnect_backoff);
908 * Connect to the set service in order to listen for requests.
910 * @param cls the `struct GNUNET_SET_ListenHandle *` to connect
913 listen_connect (void *cls)
915 GNUNET_MQ_hd_var_size (request,
916 GNUNET_MESSAGE_TYPE_SET_REQUEST,
917 struct GNUNET_SET_RequestMessage);
918 struct GNUNET_SET_ListenHandle *lh = cls;
919 struct GNUNET_MQ_MessageHandler mq_handlers[] = {
920 make_request_handler (lh),
921 GNUNET_MQ_handler_end ()
923 struct GNUNET_MQ_Envelope *mqm;
924 struct GNUNET_SET_ListenMessage *msg;
926 lh->reconnect_task = NULL;
927 GNUNET_assert (NULL == lh->client);
928 lh->client = GNUNET_CLIENT_connect ("set", lh->cfg);
929 if (NULL == lh->client)
931 GNUNET_assert (NULL == lh->mq);
932 lh->mq = GNUNET_MQ_queue_for_connection_client (lh->client,
934 &handle_client_listener_error,
936 mqm = GNUNET_MQ_msg (msg, GNUNET_MESSAGE_TYPE_SET_LISTEN);
937 msg->operation = htonl (lh->operation);
938 msg->app_id = lh->app_id;
939 GNUNET_MQ_send (lh->mq, mqm);
944 * Wait for set operation requests for the given application id
946 * @param cfg configuration to use for connecting to
947 * the set service, needs to be valid for the lifetime of the listen handle
948 * @param operation operation we want to listen for
949 * @param app_id id of the application that handles set operation requests
950 * @param listen_cb called for each incoming request matching the operation
952 * @param listen_cls handle for @a listen_cb
953 * @return a handle that can be used to cancel the listen operation
955 struct GNUNET_SET_ListenHandle *
956 GNUNET_SET_listen (const struct GNUNET_CONFIGURATION_Handle *cfg,
957 enum GNUNET_SET_OperationType operation,
958 const struct GNUNET_HashCode *app_id,
959 GNUNET_SET_ListenCallback listen_cb,
962 struct GNUNET_SET_ListenHandle *lh;
964 lh = GNUNET_new (struct GNUNET_SET_ListenHandle);
965 lh->listen_cb = listen_cb;
966 lh->listen_cls = listen_cls;
968 lh->operation = operation;
969 lh->app_id = *app_id;
970 lh->reconnect_backoff = GNUNET_TIME_UNIT_MILLISECONDS;
972 if (NULL == lh->client)
982 * Cancel the given listen operation.
984 * @param lh handle for the listen operation
987 GNUNET_SET_listen_cancel (struct GNUNET_SET_ListenHandle *lh)
989 LOG (GNUNET_ERROR_TYPE_DEBUG,
990 "Canceling listener\n");
993 GNUNET_MQ_destroy (lh->mq);
996 if (NULL != lh->client)
998 GNUNET_CLIENT_disconnect (lh->client);
1001 if (NULL != lh->reconnect_task)
1003 GNUNET_SCHEDULER_cancel (lh->reconnect_task);
1004 lh->reconnect_task = NULL;
1011 * Accept a request we got via #GNUNET_SET_listen. Must be called during
1012 * #GNUNET_SET_listen, as the 'struct GNUNET_SET_Request' becomes invalid
1014 * Call #GNUNET_SET_commit to provide the local set to use for the operation,
1015 * and to begin the exchange with the remote peer.
1017 * @param request request to accept
1018 * @param result_mode specified how results will be returned,
1019 * see `enum GNUNET_SET_ResultMode`.
1020 * @param result_cb callback for the results
1021 * @param result_cls closure for @a result_cb
1022 * @return a handle to cancel the operation
1024 struct GNUNET_SET_OperationHandle *
1025 GNUNET_SET_accept (struct GNUNET_SET_Request *request,
1026 enum GNUNET_SET_ResultMode result_mode,
1027 GNUNET_SET_ResultIterator result_cb,
1030 struct GNUNET_MQ_Envelope *mqm;
1031 struct GNUNET_SET_OperationHandle *oh;
1032 struct GNUNET_SET_AcceptMessage *msg;
1034 GNUNET_assert (GNUNET_NO == request->accepted);
1035 request->accepted = GNUNET_YES;
1036 mqm = GNUNET_MQ_msg (msg, GNUNET_MESSAGE_TYPE_SET_ACCEPT);
1037 msg->accept_reject_id = htonl (request->accept_id);
1038 msg->result_mode = htonl (result_mode);
1039 oh = GNUNET_new (struct GNUNET_SET_OperationHandle);
1040 oh->result_cb = result_cb;
1041 oh->result_cls = result_cls;
1042 oh->conclude_mqm = mqm;
1043 oh->request_id_addr = &msg->request_id;
1049 * Commit a set to be used with a set operation.
1050 * This function is called once we have fully constructed
1051 * the set that we want to use for the operation. At this
1052 * time, the P2P protocol can then begin to exchange the
1053 * set information and call the result callback with the
1054 * result information.
1056 * @param oh handle to the set operation
1057 * @param set the set to use for the operation
1058 * @return #GNUNET_OK on success, #GNUNET_SYSERR if the
1059 * set is invalid (e.g. the set service crashed)
1062 GNUNET_SET_commit (struct GNUNET_SET_OperationHandle *oh,
1063 struct GNUNET_SET_Handle *set)
1065 if (NULL != oh->set)
1067 /* Some other set was already commited for this
1068 * operation, there is a logic bug in the client of this API */
1072 if (GNUNET_YES == set->invalid)
1073 return GNUNET_SYSERR;
1074 GNUNET_assert (NULL != oh->conclude_mqm);
1076 GNUNET_CONTAINER_DLL_insert (set->ops_head,
1079 oh->request_id = GNUNET_MQ_assoc_add (set->mq, oh);
1080 *oh->request_id_addr = htonl (oh->request_id);
1081 GNUNET_MQ_send (set->mq, oh->conclude_mqm);
1082 oh->conclude_mqm = NULL;
1083 oh->request_id_addr = NULL;
1089 * Iterate over all elements in the given set. Note that this
1090 * operation involves transferring every element of the set from the
1091 * service to the client, and is thus costly.
1093 * @param set the set to iterate over
1094 * @param iter the iterator to call for each element
1095 * @param iter_cls closure for @a iter
1096 * @return #GNUNET_YES if the iteration started successfuly,
1097 * #GNUNET_NO if another iteration is active
1098 * #GNUNET_SYSERR if the set is invalid (e.g. the server crashed, disconnected)
1101 GNUNET_SET_iterate (struct GNUNET_SET_Handle *set,
1102 GNUNET_SET_ElementIterator iter,
1105 struct GNUNET_MQ_Envelope *ev;
1107 GNUNET_assert (NULL != iter);
1108 if (GNUNET_YES == set->invalid)
1109 return GNUNET_SYSERR;
1110 if (NULL != set->iterator)
1112 LOG (GNUNET_ERROR_TYPE_DEBUG,
1113 "Iterating over set\n");
1114 set->iterator = iter;
1115 set->iterator_cls = iter_cls;
1116 ev = GNUNET_MQ_msg_header (GNUNET_MESSAGE_TYPE_SET_ITER_REQUEST);
1117 GNUNET_MQ_send (set->mq, ev);
1123 GNUNET_SET_copy_lazy (struct GNUNET_SET_Handle *set,
1124 GNUNET_SET_CopyReadyCallback cb,
1127 struct GNUNET_MQ_Envelope *ev;
1128 struct SetCopyRequest *req;
1130 ev = GNUNET_MQ_msg_header (GNUNET_MESSAGE_TYPE_SET_COPY_LAZY_PREPARE);
1131 GNUNET_MQ_send (set->mq, ev);
1133 req = GNUNET_new (struct SetCopyRequest);
1136 GNUNET_CONTAINER_DLL_insert (set->copy_req_head,
1143 * Create a copy of an element. The copy
1144 * must be GNUNET_free-d by the caller.
1146 * @param element the element to copy
1147 * @return the copied element
1149 struct GNUNET_SET_Element *
1150 GNUNET_SET_element_dup (const struct GNUNET_SET_Element *element)
1152 struct GNUNET_SET_Element *copy;
1154 copy = GNUNET_malloc (element->size + sizeof (struct GNUNET_SET_Element));
1155 copy->size = element->size;
1156 copy->element_type = element->element_type;
1157 copy->data = ©[1];
1158 memcpy ((void *) copy->data, element->data, copy->size);
1165 * Hash a set element.
1167 * @param element the element that should be hashed
1168 * @param[out] ret_hash a pointer to where the hash of @a element
1172 GNUNET_SET_element_hash (const struct GNUNET_SET_Element *element,
1173 struct GNUNET_HashCode *ret_hash)
1175 struct GNUNET_HashContext *ctx = GNUNET_CRYPTO_hash_context_start ();
1177 /* It's not guaranteed that the element data is always after the element header,
1178 so we need to hash the chunks separately. */
1179 GNUNET_CRYPTO_hash_context_read (ctx, &element->size, sizeof (uint16_t));
1180 GNUNET_CRYPTO_hash_context_read (ctx, &element->element_type, sizeof (uint16_t));
1181 GNUNET_CRYPTO_hash_context_read (ctx, element->data, element->size);
1182 GNUNET_CRYPTO_hash_context_finish (ctx, ret_hash);
1185 /* end of set_api.c */