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
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_core_service.h
23 * @brief core service; this is the main API for encrypted P2P
25 * @author Christian Grothoff
28 #ifndef GNUNET_CORE_SERVICE_H
29 #define GNUNET_CORE_SERVICE_H
34 #if 0 /* keep Emacsens' auto-indent happy */
39 #include "gnunet_util_lib.h"
40 #include "gnunet_transport_service.h"
43 * Version number of GNUnet-core API.
45 #define GNUNET_CORE_VERSION 0x00000001
49 * Opaque handle to the service.
51 struct GNUNET_CORE_Handle;
55 * Method called whenever a given peer connects.
58 * @param peer peer identity this notification is about
60 typedef void (*GNUNET_CORE_ConnectEventHandler) (void *cls,
62 GNUNET_PeerIdentity * peer);
66 * Method called whenever a peer disconnects.
69 * @param peer peer identity this notification is about
71 typedef void (*GNUNET_CORE_DisconnectEventHandler) (void *cls,
73 GNUNET_PeerIdentity * peer);
77 * Functions with this signature are called whenever a message is
78 * received or transmitted.
80 * @param cls closure (set from #GNUNET_CORE_connect)
81 * @param peer the other peer involved (sender or receiver, NULL
82 * for loopback messages where we are both sender and receiver)
83 * @param message the actual message
84 * @return #GNUNET_OK to keep the connection open,
85 * #GNUNET_SYSERR to close connection to the peer (signal serious error)
87 typedef int (*GNUNET_CORE_MessageCallback) (void *cls,
88 const struct GNUNET_PeerIdentity *
90 const struct GNUNET_MessageHeader *
95 * Message handler. Each struct specifies how to handle on particular
96 * type of message received.
98 struct GNUNET_CORE_MessageHandler
101 * Function to call for messages of "type".
103 GNUNET_CORE_MessageCallback callback;
106 * Type of the message this handler covers.
111 * Expected size of messages of this type. Use 0 for variable-size.
112 * If non-zero, messages of the given type will be discarded if they
113 * do not have the right size.
115 uint16_t expected_size;
121 * Function called after #GNUNET_CORE_connect has succeeded (or failed
122 * for good). Note that the private key of the peer is intentionally
123 * not exposed here; if you need it, your process should try to read
124 * the private key file directly (which should work if you are
125 * authorized...). Implementations of this function must not call
126 * #GNUNET_CORE_disconnect (other than by scheduling a new task to
130 * @param server handle to the server, NULL if we failed;
131 * TODO: consider removing this argument, it is redundant...
132 * @param my_identity ID of this peer, NULL if we failed
134 typedef void (*GNUNET_CORE_StartupCallback) (void *cls,
135 struct GNUNET_CORE_Handle * server,
136 const struct GNUNET_PeerIdentity *
141 * Connect to the core service. Note that the connection may complete
142 * (or fail) asynchronously. This function primarily causes the given
143 * callback notification functions to be invoked whenever the
144 * specified event happens. The maximum number of queued
145 * notifications (queue length) is per client; the queue is shared
146 * across all types of notifications. So a slow client that registers
147 * for @a outbound_notify also risks missing @a inbound_notify messages.
148 * Certain events (such as connect/disconnect notifications) are not
149 * subject to queue size limitations.
151 * @param cfg configuration to use
152 * @param cls closure for the various callbacks that follow (including handlers in the handlers array)
153 * @param init callback to call once we have successfully
154 * connected to the core service
155 * @param connects function to call on peer connect, can be NULL
156 * @param disconnects function to call on peer disconnect / timeout, can be NULL
157 * @param inbound_notify function to call for all inbound messages, can be NULL
158 * note that the core is allowed to drop notifications about inbound
159 * messages if the client does not process them fast enough (for this
160 * notification type, a bounded queue is used)
161 * @param inbound_hdr_only set to #GNUNET_YES if @a inbound_notify will only read the
162 * GNUNET_MessageHeader and hence we do not need to give it the full message;
163 * can be used to improve efficiency, ignored if inbound_notify is NULL
164 * note that the core is allowed to drop notifications about inbound
165 * messages if the client does not process them fast enough (for this
166 * notification type, a bounded queue is used)
167 * @param outbound_notify function to call for all outbound messages, can be NULL;
168 * note that the core is allowed to drop notifications about outbound
169 * messages if the client does not process them fast enough (for this
170 * notification type, a bounded queue is used)
171 * @param outbound_hdr_only set to #GNUNET_YES if @a outbound_notify will only read the
172 * GNUNET_MessageHeader and hence we do not need to give it the full message
173 * can be used to improve efficiency, ignored if outbound_notify is NULL
174 * note that the core is allowed to drop notifications about outbound
175 * messages if the client does not process them fast enough (for this
176 * notification type, a bounded queue is used)
177 * @param handlers callbacks for messages we care about, NULL-terminated
178 * note that the core is allowed to drop notifications about inbound
179 * messages if the client does not process them fast enough (for this
180 * notification type, a bounded queue is used)
181 * @return handle to the core service (only useful for disconnect until @a init is called),
182 * NULL on error (in this case, init is never called)
184 struct GNUNET_CORE_Handle *
185 GNUNET_CORE_connect (const struct GNUNET_CONFIGURATION_Handle *cfg,
187 GNUNET_CORE_StartupCallback init,
188 GNUNET_CORE_ConnectEventHandler connects,
189 GNUNET_CORE_DisconnectEventHandler disconnects,
190 GNUNET_CORE_MessageCallback inbound_notify,
191 int inbound_hdr_only,
192 GNUNET_CORE_MessageCallback outbound_notify,
193 int outbound_hdr_only,
194 const struct GNUNET_CORE_MessageHandler *handlers);
198 * Disconnect from the core service. This function can only
199 * be called *after* all pending #GNUNET_CORE_notify_transmit_ready
200 * requests have been explicitly cancelled.
202 * @param handle connection to core to disconnect
205 GNUNET_CORE_disconnect (struct GNUNET_CORE_Handle *handle);
209 * Handle for a transmission request.
211 struct GNUNET_CORE_TransmitHandle;
215 * Ask the core to call @a notify once it is ready to transmit the
216 * given number of bytes to the specified @a target. Must only be
217 * called after a connection to the respective peer has been
218 * established (and the client has been informed about this). You may
219 * have one request of this type pending for each connected peer at
220 * any time. If a peer disconnects, the application MUST call
221 * #GNUNET_CORE_notify_transmit_ready_cancel on the respective
222 * transmission request, if one such request is pending.
224 * @param handle connection to core service
225 * @param cork is corking allowed for this transmission?
226 * @param priority how important is the message?
227 * @param maxdelay how long can the message wait?
228 * @param target who should receive the message, never NULL (can be this peer's identity for loopback)
229 * @param notify_size how many bytes of buffer space does notify want?
230 * @param notify function to call when buffer space is available;
231 * will be called with NULL on timeout; clients MUST cancel
232 * all pending transmission requests DURING the disconnect
234 * @param notify_cls closure for @a notify
235 * @return non-NULL if the notify callback was queued,
236 * NULL if we can not even queue the request (request already pending);
237 * if NULL is returned, "notify" will NOT be called.
239 struct GNUNET_CORE_TransmitHandle *
240 GNUNET_CORE_notify_transmit_ready (struct GNUNET_CORE_Handle *handle, int cork,
242 struct GNUNET_TIME_Relative maxdelay,
243 const struct GNUNET_PeerIdentity *target,
245 GNUNET_CONNECTION_TransmitReadyNotify notify,
250 * Cancel the specified transmission-ready notification.
252 * @param th handle that was returned by "notify_transmit_ready".
255 GNUNET_CORE_notify_transmit_ready_cancel (struct GNUNET_CORE_TransmitHandle
260 * Iterate over all connected peers. Calls @a peer_cb with each
261 * connected peer, and then once with NULL to indicate that all peers
262 * have been handled. Normal users of the CORE API are not expected
263 * to use this function. It is different in that it truly lists
264 * all connections, not just those relevant to the application. This
265 * function is used by special applications for diagnostics. This
266 * function is NOT part of the 'versioned', 'official' API.
268 * FIXME: we should probably make it possible to 'cancel' the
271 * @param cfg configuration handle
272 * @param peer_cb function to call with the peer information
273 * @param cb_cls closure for @a peer_cb
274 * @return #GNUNET_OK on success, #GNUNET_SYSERR on errors
277 GNUNET_CORE_iterate_peers (const struct GNUNET_CONFIGURATION_Handle *cfg,
278 GNUNET_CORE_ConnectEventHandler peer_cb,
283 * Handle to cancel 'is_peer_connected' test.
285 struct GNUNET_CORE_ConnectTestHandle;
289 * Check if the given peer is currently connected and return information
290 * about the session if so. This function is for special cirumstances
291 * (GNUNET_TESTING uses it), normal users of the CORE API are
292 * expected to track which peers are connected based on the
293 * connect/disconnect callbacks from GNUNET_CORE_connect. This
294 * function is NOT part of the 'versioned', 'official' API.
296 * @param cfg configuration to use
297 * @param peer the specific peer to check for
298 * @param peer_cb function to call with the peer information
299 * @param cb_cls closure for @a peer_cb
300 * @return handle to cancel the operation
302 struct GNUNET_CORE_ConnectTestHandle *
303 GNUNET_CORE_is_peer_connected (const struct GNUNET_CONFIGURATION_Handle *cfg,
304 const struct GNUNET_PeerIdentity *peer,
305 GNUNET_CORE_ConnectEventHandler peer_cb,
310 * Abort 'is_connected' test operation.
312 * @param cth handle for operation to cancel
315 GNUNET_CORE_is_peer_connected_cancel (struct GNUNET_CORE_ConnectTestHandle *cth);
319 * Check if the given peer is currently connected. This function is for special
320 * cirumstances (GNUNET_TESTBED uses it), normal users of the CORE API are
321 * expected to track which peers are connected based on the connect/disconnect
322 * callbacks from #GNUNET_CORE_connect. This function is NOT part of the
323 * 'versioned', 'official' API. The difference between this function and the
324 * function #GNUNET_CORE_is_peer_connected is that this one returns
325 * synchronously after looking in the CORE API cache. The function
326 * #GNUNET_CORE_is_peer_connected sends a message to the CORE service and hence
327 * its response is given asynchronously.
329 * @param h the core handle
330 * @param pid the identity of the peer to check if it has been connected to us
331 * @return #GNUNET_YES if the peer is connected to us; #GNUNET_NO if not
334 GNUNET_CORE_is_peer_connected_sync (const struct GNUNET_CORE_Handle *h,
335 const struct GNUNET_PeerIdentity *pid);
338 #if 0 /* keep Emacsens' auto-indent happy */
345 /* ifndef GNUNET_CORE_SERVICE_H */
347 /* end of gnunet_core_service.h */