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 * GNUNES_YES iff the join message has been sent to the service.
73 * Called when the conclude operation finishes or fails.
75 GNUNET_CONSENSUS_ConcludeCallback conclude_cb;
78 * Closure for the conclude callback.
83 * Deadline for the conclude operation.
85 struct GNUNET_TIME_Absolute conclude_deadline;
88 * Message queue for the client.
90 struct GNUNET_MQ_Handle *mq;
94 * FIXME: this should not bee necessary when the API
95 * issue has been fixed
99 GNUNET_CONSENSUS_InsertDoneCallback idc;
105 * Called when the server has sent is a new element
107 * @param cls consensus handle
108 * @param mh element message
111 handle_new_element (void *cls,
112 const struct GNUNET_MessageHeader *mh)
114 struct GNUNET_CONSENSUS_Handle *consensus = cls;
115 const struct GNUNET_CONSENSUS_ElementMessage *msg
116 = (const struct GNUNET_CONSENSUS_ElementMessage *) mh;
117 struct GNUNET_SET_Element element;
119 LOG (GNUNET_ERROR_TYPE_DEBUG, "received new element\n");
121 element.type = msg->element_type;
122 element.size = ntohs (msg->header.size) - sizeof (struct GNUNET_CONSENSUS_ElementMessage);
123 element.data = &msg[1];
125 consensus->new_element_cb (consensus->new_element_cls, &element);
130 * Called when the server has announced
131 * that the conclusion is over.
133 * @param cls consensus handle
134 * @param msg conclude done message
137 handle_conclude_done (void *cls,
138 const struct GNUNET_MessageHeader *msg)
140 struct GNUNET_CONSENSUS_Handle *consensus = cls;
142 GNUNET_CONSENSUS_ConcludeCallback cc;
144 GNUNET_assert (NULL != (cc = consensus->conclude_cb));
145 consensus->conclude_cb = NULL;
146 cc (consensus->conclude_cls);
151 * Create a consensus session.
153 * @param cfg configuration to use for connecting to the consensus service
154 * @param num_peers number of peers in the peers array
155 * @param peers array of peers participating in this consensus session
156 * Inclusion of the local peer is optional.
157 * @param session_id session identifier
158 * Allows a group of peers to have more than consensus session.
159 * @param new_element_cb callback, called when a new element is added to the set by
161 * @param new_element_cls closure for new_element
162 * @return handle to use, NULL on error
164 struct GNUNET_CONSENSUS_Handle *
165 GNUNET_CONSENSUS_create (const struct GNUNET_CONFIGURATION_Handle *cfg,
166 unsigned int num_peers,
167 const struct GNUNET_PeerIdentity *peers,
168 const struct GNUNET_HashCode *session_id,
169 GNUNET_CONSENSUS_ElementCallback new_element_cb,
170 void *new_element_cls)
172 struct GNUNET_CONSENSUS_Handle *consensus;
173 struct GNUNET_CONSENSUS_JoinMessage *join_msg;
174 struct GNUNET_MQ_Envelope *ev;
175 const static struct GNUNET_MQ_MessageHandler mq_handlers[] = {
177 GNUNET_MESSAGE_TYPE_CONSENSUS_CLIENT_RECEIVED_ELEMENT, 0},
178 {handle_conclude_done,
179 GNUNET_MESSAGE_TYPE_CONSENSUS_CLIENT_CONCLUDE_DONE, 0},
180 GNUNET_MQ_HANDLERS_END
183 consensus = GNUNET_new (struct GNUNET_CONSENSUS_Handle);
184 consensus->cfg = cfg;
185 consensus->new_element_cb = new_element_cb;
186 consensus->new_element_cls = new_element_cls;
187 consensus->session_id = *session_id;
188 consensus->client = GNUNET_CLIENT_connect ("consensus", cfg);
189 consensus->mq = GNUNET_MQ_queue_for_connection_client (consensus->client,
190 mq_handlers, NULL, consensus);
192 GNUNET_assert (consensus->client != NULL);
194 ev = GNUNET_MQ_msg_extra (join_msg,
195 (num_peers * sizeof (struct GNUNET_PeerIdentity)),
196 GNUNET_MESSAGE_TYPE_CONSENSUS_CLIENT_JOIN);
198 join_msg->session_id = consensus->session_id;
199 join_msg->num_peers = htonl (num_peers);
202 num_peers * sizeof (struct GNUNET_PeerIdentity));
204 GNUNET_MQ_send (consensus->mq, ev);
210 idc_adapter (void *cls)
212 struct InsertDoneInfo *i = cls;
213 i->idc (i->cls, GNUNET_OK);
218 * Insert an element in the set being reconsiled. Must not be called after
219 * "GNUNET_CONSENSUS_conclude".
221 * @param consensus handle for the consensus session
222 * @param element the element to be inserted
223 * @param idc function called when we are done with this element and it
224 * is thus allowed to call GNUNET_CONSENSUS_insert again
225 * @param idc_cls closure for 'idc'
228 GNUNET_CONSENSUS_insert (struct GNUNET_CONSENSUS_Handle *consensus,
229 const struct GNUNET_SET_Element *element,
230 GNUNET_CONSENSUS_InsertDoneCallback idc,
233 struct GNUNET_CONSENSUS_ElementMessage *element_msg;
234 struct GNUNET_MQ_Envelope *ev;
235 struct InsertDoneInfo *i;
237 LOG (GNUNET_ERROR_TYPE_DEBUG, "inserting, size=%llu\n", element->size);
239 ev = GNUNET_MQ_msg_extra (element_msg, element->size,
240 GNUNET_MESSAGE_TYPE_CONSENSUS_CLIENT_INSERT);
242 memcpy (&element_msg[1], element->data, element->size);
246 i = GNUNET_new (struct InsertDoneInfo);
249 GNUNET_MQ_notify_sent (ev, idc_adapter, i);
251 GNUNET_MQ_send (consensus->mq, ev);
256 * We are done with inserting new elements into the consensus;
257 * try to conclude the consensus within a given time window.
258 * After conclude has been called, no further elements may be
259 * inserted by the client.
261 * @param consensus consensus session
262 * @param deadline deadline after which the conculde callback
264 * @param conclude called when the conclusion was successful
265 * @param conclude_cls closure for the conclude callback
268 GNUNET_CONSENSUS_conclude (struct GNUNET_CONSENSUS_Handle *consensus,
269 struct GNUNET_TIME_Absolute deadline,
270 GNUNET_CONSENSUS_ConcludeCallback conclude,
273 struct GNUNET_MQ_Envelope *ev;
274 struct GNUNET_CONSENSUS_ConcludeMessage *conclude_msg;
276 GNUNET_assert (NULL != conclude);
277 GNUNET_assert (NULL == consensus->conclude_cb);
279 consensus->conclude_cls = conclude_cls;
280 consensus->conclude_cb = conclude;
282 ev = GNUNET_MQ_msg (conclude_msg, GNUNET_MESSAGE_TYPE_CONSENSUS_CLIENT_CONCLUDE);
283 conclude_msg->deadline = GNUNET_TIME_absolute_hton (deadline);
285 GNUNET_MQ_send (consensus->mq, ev);
290 * Destroy a consensus handle (free all state associated with
291 * it, no longer call any of the callbacks).
293 * @param consensus handle to destroy
296 GNUNET_CONSENSUS_destroy (struct GNUNET_CONSENSUS_Handle *consensus)
298 if (consensus->client != NULL)
300 GNUNET_CLIENT_disconnect (consensus->client);
301 consensus->client = NULL;
303 GNUNET_free (consensus);