2 This file is part of GNUnet
3 (C) 2009, 2010 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
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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
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17 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA.
21 * @file include/gnunet_peerinfo_service.h
22 * @brief Code to maintain the list of currently known hosts
23 * (in memory structure of data/hosts).
24 * @author Christian Grothoff
27 #ifndef GNUNET_PEERINFO_SERVICE_H
28 #define GNUNET_PEERINFO_SERVICE_H
30 #include "gnunet_common.h"
31 #include "gnunet_configuration_lib.h"
32 #include "gnunet_crypto_lib.h"
33 #include "gnunet_hello_lib.h"
38 #if 0 /* keep Emacsens' auto-indent happy */
45 * Handle to the peerinfo service.
47 struct GNUNET_PEERINFO_Handle;
51 * Connect to the peerinfo service.
53 * @param cfg configuration to use
54 * @return NULL on error (configuration related, actual connection
55 * etablishment may happen asynchronously).
57 struct GNUNET_PEERINFO_Handle *
58 GNUNET_PEERINFO_connect (const struct GNUNET_CONFIGURATION_Handle *cfg);
62 * Disconnect from the peerinfo service. Note that all iterators must
63 * have completed or have been cancelled by the time this function is
64 * called (otherwise, calling this function is a serious error).
65 * Furthermore, if 'GNUNET_PEERINFO_add_peer' operations are still
66 * pending, they will be cancelled silently on disconnect.
68 * @param h handle to disconnect
71 GNUNET_PEERINFO_disconnect (struct GNUNET_PEERINFO_Handle *h);
75 * Continuation called with a status result.
78 * @param emsg error message, NULL on success
80 typedef void (*GNUNET_PEERINFO_Continuation)(void *cls,
85 * Opaque handle to cancel 'add' operation.
87 struct GNUNET_PEERINFO_AddContext;
91 * Add a host to the persistent list. This method operates in
92 * semi-reliable mode: if the transmission is not completed by
93 * the time 'GNUNET_PEERINFO_disconnect' is called, it will be
94 * aborted. Furthermore, if a second HELLO is added for the
95 * same peer before the first one was transmitted, PEERINFO may
96 * merge the two HELLOs prior to transmission to the service.
98 * @param h handle to the peerinfo service
99 * @param hello the verified (!) HELLO message
100 * @param cont continuation to call when done, NULL is allowed
101 * @param cont_cls closure for 'cont'
102 * @return handle to cancel add operation; all pending
103 * 'add' operations will be cancelled automatically
104 * on disconnect, so it is not necessary to keep this
105 * handle (unless 'cont' is NULL and at some point
106 * calling 'cont' must be prevented)
108 struct GNUNET_PEERINFO_AddContext *
109 GNUNET_PEERINFO_add_peer (struct GNUNET_PEERINFO_Handle *h,
110 const struct GNUNET_HELLO_Message *hello,
111 GNUNET_PEERINFO_Continuation cont,
116 * Cancel pending 'add' operation. Must only be called before
117 * either 'cont' or 'GNUNET_PEERINFO_disconnect' are invoked.
119 * @param ac handle for the add operation to cancel
122 GNUNET_PEERINFO_add_peer_cancel (struct GNUNET_PEERINFO_AddContext *ac);
126 * Type of an iterator over the hosts. Note that each
127 * host will be called with each available protocol.
130 * @param peer id of the peer, NULL for last call
131 * @param hello hello message for the peer (can be NULL)
132 * @param error message
134 typedef void (*GNUNET_PEERINFO_Processor) (void *cls,
135 const struct GNUNET_PeerIdentity *
137 const struct GNUNET_HELLO_Message *
138 hello, const char *err_msg);
142 * Handle for cancellation of iteration over peers.
144 struct GNUNET_PEERINFO_IteratorContext;
148 * Call a method for each known matching host. The callback method
149 * will be invoked once for each matching host and then finally once
150 * with a NULL pointer. After that final invocation, the iterator
151 * context must no longer be used.
153 * Instead of calling this function with 'peer == NULL' it is often
154 * better to use 'GNUNET_PEERINFO_notify'.
156 * @param h handle to the peerinfo service
157 * @param include_friend_only include HELLO messages for friends only
158 * @param peer restrict iteration to this peer only (can be NULL)
159 * @param timeout how long to wait until timing out
160 * @param callback the method to call for each peer
161 * @param callback_cls closure for callback
162 * @return iterator context
164 struct GNUNET_PEERINFO_IteratorContext *
165 GNUNET_PEERINFO_iterate (struct GNUNET_PEERINFO_Handle *h,
166 int include_friend_only,
167 const struct GNUNET_PeerIdentity *peer,
168 struct GNUNET_TIME_Relative timeout,
169 GNUNET_PEERINFO_Processor callback, void *callback_cls);
174 * Cancel an iteration over peer information.
176 * @param ic context of the iterator to cancel
179 GNUNET_PEERINFO_iterate_cancel (struct GNUNET_PEERINFO_IteratorContext *ic);
184 * Handle for notifications about changes to the set of known peers.
186 struct GNUNET_PEERINFO_NotifyContext;
190 * Call a method whenever our known information about peers
191 * changes. Initially calls the given function for all known
192 * peers and then only signals changes.
194 * If include_friend_only is set to GNUNET_YES peerinfo will include HELLO
195 * messages which are intended for friend to friend mode and which do not
196 * have to be gossiped. Otherwise these messages are skipped.
198 * @param cfg configuration to use
199 * @param include_friend_only include HELLO messages for friends only
200 * @param callback the method to call for each peer
201 * @param callback_cls closure for callback
202 * @return NULL on error
204 struct GNUNET_PEERINFO_NotifyContext *
205 GNUNET_PEERINFO_notify (const struct GNUNET_CONFIGURATION_Handle *cfg,
206 int include_friend_only,
207 GNUNET_PEERINFO_Processor callback, void *callback_cls);
211 * Stop notifying about changes.
213 * @param nc context to stop notifying
216 GNUNET_PEERINFO_notify_cancel (struct GNUNET_PEERINFO_NotifyContext *nc);
219 #if 0 /* keep Emacsens' auto-indent happy */
227 /* end of gnunet_peerinfo_service.h */