2 This file is part of GNUnet.
3 (C) 2012 Christian Grothoff (and other contributing authors)
5 GNUnet is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published
7 by the Free Software Foundation; either version 3, or (at your
8 option) any later version.
10 GNUnet is distributed in the hope that it will be useful, but
11 WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with GNUnet; see the file COPYING. If not, write to the
17 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA.
22 * @file consensus/consensus_api.c
24 * @author Florian Dold
27 #include "gnunet_util_lib.h"
28 #include "gnunet_protocols.h"
29 #include "gnunet_client_lib.h"
30 #include "gnunet_consensus_service.h"
31 #include "consensus.h"
34 #define LOG(kind,...) GNUNET_log_from (kind, "consensus-api",__VA_ARGS__)
38 * Handle for the service.
40 struct GNUNET_CONSENSUS_Handle
43 * Configuration to use.
45 const struct GNUNET_CONFIGURATION_Handle *cfg;
48 * Client connected to the consensus service, may be NULL if not connected.
50 struct GNUNET_CLIENT_Connection *client;
53 * Callback for new elements. Not called for elements added locally.
55 GNUNET_CONSENSUS_ElementCallback new_element_cb;
58 * Closure for new_element_cb
60 void *new_element_cls;
63 * The (local) session identifier for the consensus session.
65 struct GNUNET_HashCode session_id;
68 * Number of peers in the consensus. Optionally includes the local peer.
73 * Peer identities of peers participating in the consensus, includes the local peer.
75 struct GNUNET_PeerIdentity **peers;
78 * GNUNES_YES iff the join message has been sent to the service.
83 * Called when the conclude operation finishes or fails.
85 GNUNET_CONSENSUS_ConcludeCallback conclude_cb;
88 * Closure for the conclude callback.
93 * Deadline for the conclude operation.
95 struct GNUNET_TIME_Absolute conclude_deadline;
98 * Message queue for the client.
100 struct GNUNET_MQ_Handle *mq;
104 * FIXME: this should not bee necessary when the API
105 * issue has been fixed
107 struct InsertDoneInfo
109 GNUNET_CONSENSUS_InsertDoneCallback idc;
115 * Called when the server has sent is a new element
117 * @param cls consensus handle
118 * @param mh element message
121 handle_new_element (void *cls,
122 const struct GNUNET_MessageHeader *mh)
124 struct GNUNET_CONSENSUS_Handle *consensus = cls;
125 const struct GNUNET_CONSENSUS_ElementMessage *msg
126 = (const struct GNUNET_CONSENSUS_ElementMessage *) mh;
127 struct GNUNET_SET_Element element;
129 LOG (GNUNET_ERROR_TYPE_DEBUG, "received new element\n");
131 element.type = msg->element_type;
132 element.size = ntohs (msg->header.size) - sizeof (struct GNUNET_CONSENSUS_ElementMessage);
133 element.data = &msg[1];
135 consensus->new_element_cb (consensus->new_element_cls, &element);
140 * Called when the server has announced
141 * that the conclusion is over.
143 * @param cls consensus handle
144 * @param msg conclude done message
147 handle_conclude_done (void *cls,
148 const struct GNUNET_MessageHeader *msg)
150 struct GNUNET_CONSENSUS_Handle *consensus = cls;
152 GNUNET_CONSENSUS_ConcludeCallback cc;
154 GNUNET_assert (NULL != (cc = consensus->conclude_cb));
155 consensus->conclude_cb = NULL;
156 cc (consensus->conclude_cls);
161 * Create a consensus session.
163 * @param cfg configuration to use for connecting to the consensus service
164 * @param num_peers number of peers in the peers array
165 * @param peers array of peers participating in this consensus session
166 * Inclusion of the local peer is optional.
167 * @param session_id session identifier
168 * Allows a group of peers to have more than consensus session.
169 * @param new_element_cb callback, called when a new element is added to the set by
171 * @param new_element_cls closure for new_element
172 * @return handle to use, NULL on error
174 struct GNUNET_CONSENSUS_Handle *
175 GNUNET_CONSENSUS_create (const struct GNUNET_CONFIGURATION_Handle *cfg,
176 unsigned int num_peers,
177 const struct GNUNET_PeerIdentity *peers,
178 const struct GNUNET_HashCode *session_id,
179 GNUNET_CONSENSUS_ElementCallback new_element_cb,
180 void *new_element_cls)
182 struct GNUNET_CONSENSUS_Handle *consensus;
183 struct GNUNET_CONSENSUS_JoinMessage *join_msg;
184 struct GNUNET_MQ_Envelope *ev;
185 const static struct GNUNET_MQ_MessageHandler mq_handlers[] = {
187 GNUNET_MESSAGE_TYPE_CONSENSUS_CLIENT_RECEIVED_ELEMENT, 0},
188 {handle_conclude_done,
189 GNUNET_MESSAGE_TYPE_CONSENSUS_CLIENT_CONCLUDE_DONE, 0},
190 GNUNET_MQ_HANDLERS_END
193 consensus = GNUNET_malloc (sizeof (struct GNUNET_CONSENSUS_Handle));
194 consensus->cfg = cfg;
195 consensus->new_element_cb = new_element_cb;
196 consensus->new_element_cls = new_element_cls;
197 consensus->num_peers = num_peers;
198 consensus->session_id = *session_id;
201 consensus->peers = NULL;
202 else if (num_peers > 0)
204 GNUNET_memdup (peers, num_peers * sizeof (struct GNUNET_PeerIdentity));
206 consensus->client = GNUNET_CLIENT_connect ("consensus", cfg);
207 consensus->mq = GNUNET_MQ_queue_for_connection_client (consensus->client,
208 mq_handlers, NULL, consensus);
210 GNUNET_assert (consensus->client != NULL);
212 ev = GNUNET_MQ_msg_extra (join_msg,
213 (num_peers * sizeof (struct GNUNET_PeerIdentity)),
214 GNUNET_MESSAGE_TYPE_CONSENSUS_CLIENT_JOIN);
216 join_msg->session_id = consensus->session_id;
217 join_msg->num_peers = htonl (consensus->num_peers);
220 consensus->num_peers * sizeof (struct GNUNET_PeerIdentity));
222 GNUNET_MQ_send (consensus->mq, ev);
228 idc_adapter (void *cls)
230 struct InsertDoneInfo *i = cls;
231 i->idc (i->cls, GNUNET_OK);
236 * Insert an element in the set being reconsiled. Must not be called after
237 * "GNUNET_CONSENSUS_conclude".
239 * @param consensus handle for the consensus session
240 * @param element the element to be inserted
241 * @param idc function called when we are done with this element and it
242 * is thus allowed to call GNUNET_CONSENSUS_insert again
243 * @param idc_cls closure for 'idc'
246 GNUNET_CONSENSUS_insert (struct GNUNET_CONSENSUS_Handle *consensus,
247 const struct GNUNET_SET_Element *element,
248 GNUNET_CONSENSUS_InsertDoneCallback idc,
251 struct GNUNET_CONSENSUS_ElementMessage *element_msg;
252 struct GNUNET_MQ_Envelope *ev;
253 struct InsertDoneInfo *i;
255 LOG (GNUNET_ERROR_TYPE_DEBUG, "inserting, size=%llu\n", element->size);
257 ev = GNUNET_MQ_msg_extra (element_msg, element->size,
258 GNUNET_MESSAGE_TYPE_CONSENSUS_CLIENT_INSERT);
260 memcpy (&element_msg[1], element->data, element->size);
264 i = GNUNET_new (struct InsertDoneInfo);
267 GNUNET_MQ_notify_sent (ev, idc_adapter, i);
273 * We are done with inserting new elements into the consensus;
274 * try to conclude the consensus within a given time window.
275 * After conclude has been called, no further elements may be
276 * inserted by the client.
278 * @param consensus consensus session
279 * @param timeout timeout after which the conculde callback
281 * @param conclude called when the conclusion was successful
282 * @param conclude_cls closure for the conclude callback
285 GNUNET_CONSENSUS_conclude (struct GNUNET_CONSENSUS_Handle *consensus,
286 struct GNUNET_TIME_Relative timeout,
287 GNUNET_CONSENSUS_ConcludeCallback conclude,
290 struct GNUNET_MQ_Envelope *ev;
291 struct GNUNET_CONSENSUS_ConcludeMessage *conclude_msg;
293 GNUNET_assert (NULL != conclude);
294 GNUNET_assert (NULL == consensus->conclude_cb);
296 consensus->conclude_cls = conclude_cls;
297 consensus->conclude_cb = conclude;
299 ev = GNUNET_MQ_msg (conclude_msg, GNUNET_MESSAGE_TYPE_CONSENSUS_CLIENT_CONCLUDE);
300 conclude_msg->timeout = GNUNET_TIME_relative_hton (timeout);
302 GNUNET_MQ_send (consensus->mq, ev);
307 * Destroy a consensus handle (free all state associated with
308 * it, no longer call any of the callbacks).
310 * @param consensus handle to destroy
313 GNUNET_CONSENSUS_destroy (struct GNUNET_CONSENSUS_Handle *consensus)
315 if (consensus->client != NULL)
317 GNUNET_CLIENT_disconnect (consensus->client);
318 consensus->client = NULL;
320 if (NULL != consensus->peers)
321 GNUNET_free (consensus->peers);
322 GNUNET_free (consensus);