2 This file is part of GNUnet.
3 (C) 2009, 2010 Christian Grothoff (and other contributing authors)
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6 it under the terms of the GNU General Public License as published
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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.
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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 it (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; TODO: consider removing this argument, it is redundant...
131 * @param my_identity ID of this peer, NULL if we failed
133 typedef void (*GNUNET_CORE_StartupCallback) (void *cls,
134 struct GNUNET_CORE_Handle * server,
135 const struct GNUNET_PeerIdentity *
140 * Connect to the core service. Note that the connection may complete
141 * (or fail) asynchronously. This function primarily causes the given
142 * callback notification functions to be invoked whenever the
143 * specified event happens. The maximum number of queued
144 * notifications (queue length) is per client; the queue is shared
145 * across all types of notifications. So a slow client that registers
146 * for 'outbound_notify' also risks missing 'inbound_notify' messages.
147 * Certain events (such as connect/disconnect notifications) are not
148 * subject to queue size limitations.
150 * @param cfg configuration to use
151 * @param cls closure for the various callbacks that follow (including handlers in the handlers array)
152 * @param init callback to call once we have successfully
153 * connected to the core service
154 * @param connects function to call on peer connect, can be NULL
155 * @param disconnects function to call on peer disconnect / timeout, can be NULL
156 * @param inbound_notify function to call for all inbound messages, can be NULL
157 * note that the core is allowed to drop notifications about inbound
158 * messages if the client does not process them fast enough (for this
159 * notification type, a bounded queue is used)
160 * @param inbound_hdr_only set to GNUNET_YES if inbound_notify will only read the
161 * GNUNET_MessageHeader and hence we do not need to give it the full message;
162 * can be used to improve efficiency, ignored if inbound_notify is NULL
163 * note that the core is allowed to drop notifications about inbound
164 * messages if the client does not process them fast enough (for this
165 * notification type, a bounded queue is used)
166 * @param outbound_notify function to call for all outbound messages, can be NULL;
167 * note that the core is allowed to drop notifications about outbound
168 * messages if the client does not process them fast enough (for this
169 * notification type, a bounded queue is used)
170 * @param outbound_hdr_only set to GNUNET_YES if outbound_notify will only read the
171 * GNUNET_MessageHeader and hence we do not need to give it the full message
172 * can be used to improve efficiency, ignored if outbound_notify is NULL
173 * note that the core is allowed to drop notifications about outbound
174 * messages if the client does not process them fast enough (for this
175 * notification type, a bounded queue is used)
176 * @param handlers callbacks for messages we care about, NULL-terminated
177 * note that the core is allowed to drop notifications about inbound
178 * messages if the client does not process them fast enough (for this
179 * notification type, a bounded queue is used)
180 * @return handle to the core service (only useful for disconnect until 'init' is called),
181 * NULL on error (in this case, init is never called)
183 struct GNUNET_CORE_Handle *
184 GNUNET_CORE_connect (const struct GNUNET_CONFIGURATION_Handle *cfg,
186 GNUNET_CORE_StartupCallback init,
187 GNUNET_CORE_ConnectEventHandler connects,
188 GNUNET_CORE_DisconnectEventHandler disconnects,
189 GNUNET_CORE_MessageCallback inbound_notify,
190 int inbound_hdr_only,
191 GNUNET_CORE_MessageCallback outbound_notify,
192 int outbound_hdr_only,
193 const struct GNUNET_CORE_MessageHandler *handlers);
197 * Disconnect from the core service. This function can only
198 * be called *after* all pending 'GNUNET_CORE_notify_transmit_ready'
199 * requests have been explicitly cancelled.
201 * @param handle connection to core to disconnect
204 GNUNET_CORE_disconnect (struct GNUNET_CORE_Handle *handle);
208 * Handle for a transmission request.
210 struct GNUNET_CORE_TransmitHandle;
214 * Ask the core to call "notify" once it is ready to transmit the
215 * given number of bytes to the specified "target". Must only be
216 * called after a connection to the respective peer has been
217 * established (and the client has been informed about this). You may
218 * have one request of this type pending for each connected peer at
219 * any time. If a peer disconnects, the application MUST call
220 * "GNUNET_CORE_notify_transmit_ready_cancel" on the respective
221 * transmission request, if one such request is pending.
223 * @param handle connection to core service
224 * @param cork is corking allowed for this transmission?
225 * @param priority how important is the message?
226 * @param maxdelay how long can the message wait?
227 * @param target who should receive the message, never NULL (can be this peer's identity for loopback)
228 * @param notify_size how many bytes of buffer space does notify want?
229 * @param notify function to call when buffer space is available;
230 * will be called with NULL on timeout; clients MUST cancel
231 * all pending transmission requests DURING the disconnect
233 * @param notify_cls closure for notify
234 * @return non-NULL if the notify callback was queued,
235 * NULL if we can not even queue the request (request already pending);
236 * if NULL is returned, "notify" will NOT be called.
238 struct GNUNET_CORE_TransmitHandle *
239 GNUNET_CORE_notify_transmit_ready (struct GNUNET_CORE_Handle *handle, int cork,
241 struct GNUNET_TIME_Relative maxdelay,
242 const struct GNUNET_PeerIdentity *target,
244 GNUNET_CONNECTION_TransmitReadyNotify notify,
249 * Cancel the specified transmission-ready notification.
251 * @param th handle that was returned by "notify_transmit_ready".
254 GNUNET_CORE_notify_transmit_ready_cancel (struct GNUNET_CORE_TransmitHandle
262 * Iterate over all connected peers. Calls peer_cb with each
263 * connected peer, and then once with NULL to indicate that all peers
264 * have been handled. Normal users of the CORE API are not expected
265 * to use this function. It is different in that it truly lists
266 * all connections, not just those relevant to the application. This
267 * function is used by special applications for diagnostics. This
268 * function is NOT part of the 'versioned', 'official' API.
270 * FIXME: we should probably make it possible to 'cancel' the
273 * @param cfg configuration handle
274 * @param peer_cb function to call with the peer information
275 * @param cb_cls closure for peer_cb
276 * @return GNUNET_OK on success, GNUNET_SYSERR on errors
279 GNUNET_CORE_iterate_peers (const struct GNUNET_CONFIGURATION_Handle *cfg,
280 GNUNET_CORE_ConnectEventHandler peer_cb,
285 * Handle to cancel 'is_peer_connected' test.
287 struct GNUNET_CORE_ConnectTestHandle;
291 * Check if the given peer is currently connected and return information
292 * about the session if so. This function is for special cirumstances
293 * (GNUNET_TESTING uses it), normal users of the CORE API are
294 * expected to track which peers are connected based on the
295 * connect/disconnect callbacks from GNUNET_CORE_connect. This
296 * function is NOT part of the 'versioned', 'official' API.
298 * @param cfg configuration to use
299 * @param peer the specific peer to check for
300 * @param peer_cb function to call with the peer information
301 * @param cb_cls closure for peer_cb
302 * @return handle to cancel the operation
304 struct GNUNET_CORE_ConnectTestHandle *
305 GNUNET_CORE_is_peer_connected (const struct GNUNET_CONFIGURATION_Handle *cfg,
306 const struct GNUNET_PeerIdentity *peer,
307 GNUNET_CORE_ConnectEventHandler peer_cb,
312 * Abort 'is_connected' test operation.
314 * @param cth handle for operation to cancel
317 GNUNET_CORE_is_peer_connected_cancel (struct GNUNET_CORE_ConnectTestHandle *cth);
321 * Check if the given peer is currently connected. This function is for special
322 * cirumstances (GNUNET_TESTBED uses it), normal users of the CORE API are
323 * expected to track which peers are connected based on the connect/disconnect
324 * callbacks from GNUNET_CORE_connect. This function is NOT part of the
325 * 'versioned', 'official' API. The difference between this function and the
326 * function GNUNET_CORE_is_peer_connected() is that this one returns
327 * synchronously after looking in the CORE API cache. The function
328 * GNUNET_CORE_is_peer_connected() sends a message to the CORE service and hence
329 * its response is given asynchronously.
331 * @param h the core handle
332 * @param pid the identity of the peer to check if it has been connected to us
333 * @return GNUNET_YES if the peer is connected to us; GNUNET_NO if not
336 GNUNET_CORE_is_peer_connected_sync (const struct GNUNET_CORE_Handle *h,
337 const struct GNUNET_PeerIdentity *pid);
340 #if 0 /* keep Emacsens' auto-indent happy */
347 /* ifndef GNUNET_CORE_SERVICE_H */
349 /* end of gnunet_core_service.h */