2 This file is part of GNUnet
3 (C) 2013 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 2, 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 include/gnunet_set_service.h
23 * @brief two-peer set operations
24 * @author Florian Dold
27 #ifndef GNUNET_SET_SERVICE_H
28 #define GNUNET_SET_SERVICE_H
33 #if 0 /* keep Emacsens' auto-indent happy */
39 #include "gnunet_common.h"
40 #include "gnunet_time_lib.h"
41 #include "gnunet_configuration_lib.h"
45 * Opaque handle to a set.
47 struct GNUNET_SET_Handle;
50 * Opaque handle to a set operation request from another peer.
52 struct GNUNET_SET_Request;
55 * Opaque handle to a listen operation.
57 struct GNUNET_SET_ListenHandle;
60 * Opaque handle to a set operation.
62 struct GNUNET_SET_OperationHandle;
66 * The operation that a set set supports.
68 enum GNUNET_SET_OperationType
71 * Set intersection, only return elements that are in both sets.
73 GNUNET_SET_OPERATION_INTERSECTION,
75 * Set union, return all elements that are in at least one of the sets.
77 GNUNET_SET_OPERATION_UNION
81 * Status for the result callback
83 enum GNUNET_SET_Status
90 * There was a timeout.
92 GNUNET_SET_STATUS_TIMEOUT,
94 * The other peer refused to to the operation with us,
95 * or something went wrong.
97 GNUNET_SET_STATUS_FAILURE,
99 * Success, all elements have been sent.
101 GNUNET_SET_STATUS_DONE
105 * The way results are given to the client.
107 enum GNUNET_SET_ResultMode
110 * Client gets every element in the resulting set.
112 GNUNET_SET_RESULT_FULL,
114 * Client gets only elements that have been added to the set.
115 * Only works with set union.
117 GNUNET_SET_RESULT_ADDED,
119 * Client gets only elements that have been removed from the set.
120 * Only works with set intersection.
122 GNUNET_SET_RESULT_REMOVED
126 * Element stored in a set.
128 struct GNUNET_SET_Element
131 * Number of bytes in the buffer pointed to by data.
136 * Application-specific element type.
141 * Actual data of the element
148 * Continuation used for some of the set operations
152 typedef void (*GNUNET_SET_Continuation) (void *cls);
156 * Callback for set operation results. Called for each element
160 * @param element a result element, only valid if status is GNUNET_SET_STATUS_OK
161 * @param status see enum GNUNET_SET_Status
163 typedef void (*GNUNET_SET_ResultIterator) (void *cls,
164 struct GNUNET_SET_Element *element,
165 enum GNUNET_SET_Status status);
169 * Called when another peer wants to do a set operation with the
172 * @param other_peer the other peer
173 * @param context_msg message with application specific information from
175 * @param request request from the other peer, use GNUNET_SET_accept
176 * to accept it, otherwise the request will be refused
177 * Note that we don't use a return value here, as it is also
178 * necessary to specify the set we want to do the operation with,
179 * whith sometimes can be derived from the context message.
180 * Also necessary to specify the timeout.
183 (*GNUNET_SET_ListenCallback) (void *cls,
184 const struct GNUNET_PeerIdentity *other_peer,
185 const struct GNUNET_MessageHeader *context_msg,
186 struct GNUNET_SET_Request *request);
191 * Create an empty set, supporting the specified operation.
193 * @param cfg configuration to use for connecting to the
195 * @param op operation supported by the set
196 * Note that the operation has to be specified
197 * beforehand, as certain set operations need to maintain
198 * data structures spefific to the operation
199 * @return a handle to the set
201 struct GNUNET_SET_Handle *
202 GNUNET_SET_create (const struct GNUNET_CONFIGURATION_Handle *cfg,
203 enum GNUNET_SET_OperationType op);
207 * Add an element to the given set.
208 * After the element has been added (in the sense of being
209 * transmitted to the set service), cont will be called.
210 * Calls to add_element can be queued
212 * @param set set to add element to
213 * @param element element to add to the set
214 * @param cont continuation called after the element has been added
215 * @param cont_cls closure for cont
218 GNUNET_SET_add_element (struct GNUNET_SET_Handle *set,
219 const struct GNUNET_SET_Element *element,
220 GNUNET_SET_Continuation cont,
225 * Remove an element to the given set.
226 * After the element has been removed (in the sense of the
227 * request being transmitted to the set service), cont will be called.
228 * Calls to remove_element can be queued
230 * @param set set to remove element from
231 * @param element element to remove from the set
232 * @param cont continuation called after the element has been removed
233 * @param cont_cls closure for cont
236 GNUNET_SET_remove_element (struct GNUNET_SET_Handle *set,
237 const struct GNUNET_SET_Element *element,
238 GNUNET_SET_Continuation cont,
243 * Destroy the set handle, and free all associated resources.
246 GNUNET_SET_destroy (struct GNUNET_SET_Handle *set);
250 * Evaluate a set operation with our set and the set of another peer.
252 * @param set set to use
253 * @param salt salt for HKDF (explain more here)
254 * @param other_peer peer with the other set
255 * @param app_id hash for the application using the set
256 * @param context_msg additional information for the request
257 * @param salt salt used for the set operation; sometimes set operations
258 * fail due to hash collisions, using a different salt for each operation
259 * makes it harder for an attacker to exploit this
260 * @param timeout result_cb will be called with GNUNET_SET_STATUS_TIMEOUT
261 * if the operation is not done after the specified time
262 * @param result_mode specified how results will be returned,
263 * see 'GNUNET_SET_ResultMode'.
264 * @param result_cb called on error or success
265 * @param result_cls closure for result_cb
266 * @return a handle to cancel the operation
268 struct GNUNET_SET_OperationHandle *
269 GNUNET_SET_evaluate (struct GNUNET_SET_Handle *set,
270 const struct GNUNET_PeerIdentity *other_peer,
271 const struct GNUNET_HashCode *app_id,
272 const struct GNUNET_MessageHeader *context_msg,
274 struct GNUNET_TIME_Relative timeout,
275 enum GNUNET_SET_ResultMode result_mode,
276 GNUNET_SET_ResultIterator result_cb,
281 * Wait for set operation requests for the given application id
283 * @param cfg configuration to use for connecting to
285 * @param operation operation we want to listen for
286 * @param app_id id of the application that handles set operation requests
287 * @param listen_cb called for each incoming request matching the operation
289 * @param listen_cls handle for listen_cb
290 * @return a handle that can be used to cancel the listen operation
292 struct GNUNET_SET_ListenHandle *
293 GNUNET_SET_listen (const struct GNUNET_CONFIGURATION_Handle *cfg,
294 enum GNUNET_SET_OperationType op_type,
295 const struct GNUNET_HashCode *app_id,
296 GNUNET_SET_ListenCallback listen_cb,
302 * Cancel the given listen operation.
304 * @param lh handle for the listen operation
307 GNUNET_SET_listen_cancel (struct GNUNET_SET_ListenHandle *lh);
312 * Accept a request we got via GNUNET_SET_listen.
314 * @param request request to accept
315 * @param set set used for the requested operation
316 * @param timeout timeout for the set operation
317 * @param result_mode specified how results will be returned,
318 * see 'GNUNET_SET_ResultMode'.
319 * @param result_cb callback for the results
320 * @param result_cls closure for result_cb
321 * @return a handle to cancel the operation
323 struct GNUNET_SET_OperationHandle *
324 GNUNET_SET_accept (struct GNUNET_SET_Request *request,
325 struct GNUNET_SET_Handle *set,
326 struct GNUNET_TIME_Relative timeout,
327 enum GNUNET_SET_ResultMode result_mode,
328 GNUNET_SET_ResultIterator result_cb,
333 * Cancel the given set operation.
335 * @param oh set operation to cancel
338 GNUNET_SET_operation_cancel (struct GNUNET_SET_OperationHandle *oh);
341 #if 0 /* keep Emacsens' auto-indent happy */