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21 * @file ats/ats_api_connectivity.c
22 * @brief enable clients to ask ATS about establishing connections to peers
23 * @author Christian Grothoff
24 * @author Matthias Wachs
27 #include "gnunet_ats_service.h"
31 #define LOG(kind,...) GNUNET_log_from(kind, "ats-connectivity-api", __VA_ARGS__)
35 * Handle for ATS address suggestion requests.
37 struct GNUNET_ATS_ConnectivitySuggestHandle
40 * ID of the peer for which address suggestion was requested.
42 struct GNUNET_PeerIdentity id;
45 * Connecitivity handle this suggestion handle belongs to.
47 struct GNUNET_ATS_ConnectivityHandle *ch;
50 * How urgent is the request.
57 * Handle to the ATS subsystem for connectivity management.
59 struct GNUNET_ATS_ConnectivityHandle
65 const struct GNUNET_CONFIGURATION_Handle *cfg;
68 * Map with the identities of all the peers for which we would
69 * like to have address suggestions. The key is the PID, the
70 * value is currently the `struct GNUNET_ATS_ConnectivitySuggestHandle`
72 struct GNUNET_CONTAINER_MultiPeerMap *sug_requests;
75 * Message queue for sending requests to the ATS service.
77 struct GNUNET_MQ_Handle *mq;
80 * Task to trigger reconnect.
82 struct GNUNET_SCHEDULER_Task *task;
85 * Reconnect backoff delay.
87 struct GNUNET_TIME_Relative backoff;
92 * Re-establish the connection to the ATS service.
94 * @param ch handle to use to re-connect.
97 reconnect (struct GNUNET_ATS_ConnectivityHandle *ch);
101 * Re-establish the connection to the ATS service.
103 * @param cls handle to use to re-connect.
106 reconnect_task (void *cls)
108 struct GNUNET_ATS_ConnectivityHandle *ch = cls;
116 * Disconnect from ATS and then reconnect.
118 * @param ch our handle
121 force_reconnect (struct GNUNET_ATS_ConnectivityHandle *ch)
125 GNUNET_MQ_destroy (ch->mq);
128 ch->backoff = GNUNET_TIME_STD_BACKOFF (ch->backoff);
129 ch->task = GNUNET_SCHEDULER_add_delayed (ch->backoff,
136 * We encountered an error handling the MQ to the
137 * ATS service. Reconnect.
139 * @param cls the `struct GNUNET_ATS_ConnectivityHandle`
140 * @param error details about the error
143 error_handler (void *cls,
144 enum GNUNET_MQ_Error error)
146 struct GNUNET_ATS_ConnectivityHandle *ch = cls;
148 LOG (GNUNET_ERROR_TYPE_DEBUG,
149 "ATS connection died (code %d), reconnecting\n",
151 force_reconnect (ch);
156 * Transmit request for an address suggestion.
158 * @param cls the `struct GNUNET_ATS_ConnectivityHandle`
159 * @param peer peer to ask for an address suggestion for
160 * @param value the `struct GNUNET_ATS_SuggestHandle`
161 * @return #GNUNET_OK (continue to iterate), #GNUNET_SYSERR on
162 * failure (message queue no longer exists)
165 transmit_suggestion (void *cls,
166 const struct GNUNET_PeerIdentity *peer,
169 struct GNUNET_ATS_ConnectivityHandle *ch = cls;
170 struct GNUNET_ATS_ConnectivitySuggestHandle *sh = value;
171 struct GNUNET_MQ_Envelope *ev;
172 struct RequestAddressMessage *m;
175 return GNUNET_SYSERR;
176 ev = GNUNET_MQ_msg (m, GNUNET_MESSAGE_TYPE_ATS_REQUEST_ADDRESS);
177 m->strength = htonl (sh->strength);
179 GNUNET_MQ_send (ch->mq, ev);
185 * Re-establish the connection to the ATS service.
187 * @param ch handle to use to re-connect.
190 reconnect (struct GNUNET_ATS_ConnectivityHandle *ch)
192 static const struct GNUNET_MQ_MessageHandler handlers[] =
194 struct GNUNET_MQ_Envelope *ev;
195 struct ClientStartMessage *init;
197 GNUNET_assert (NULL == ch->mq);
198 ch->mq = GNUNET_CLIENT_connect (ch->cfg,
205 force_reconnect (ch);
208 ev = GNUNET_MQ_msg (init,
209 GNUNET_MESSAGE_TYPE_ATS_START);
210 init->start_flag = htonl (START_FLAG_CONNECTION_SUGGESTION);
211 GNUNET_MQ_send (ch->mq, ev);
214 GNUNET_CONTAINER_multipeermap_iterate (ch->sug_requests,
215 &transmit_suggestion,
221 * Initialize the ATS connectivity suggestion client handle.
223 * @param cfg configuration to use
224 * @return ats connectivity handle, NULL on error
226 struct GNUNET_ATS_ConnectivityHandle *
227 GNUNET_ATS_connectivity_init (const struct GNUNET_CONFIGURATION_Handle *cfg)
229 struct GNUNET_ATS_ConnectivityHandle *ch;
231 ch = GNUNET_new (struct GNUNET_ATS_ConnectivityHandle);
233 ch->sug_requests = GNUNET_CONTAINER_multipeermap_create (32,
241 * Function called to free all `struct GNUNET_ATS_ConnectivitySuggestHandle`s
246 * @param value the value to free
247 * @return #GNUNET_OK (continue to iterate)
250 free_sug_handle (void *cls,
251 const struct GNUNET_PeerIdentity *key,
254 struct GNUNET_ATS_ConnectivitySuggestHandle *cur = value;
262 * Client is done with ATS connectivity management, release resources.
264 * @param ch handle to release
267 GNUNET_ATS_connectivity_done (struct GNUNET_ATS_ConnectivityHandle *ch)
271 GNUNET_MQ_destroy (ch->mq);
274 if (NULL != ch->task)
276 GNUNET_SCHEDULER_cancel (ch->task);
279 GNUNET_CONTAINER_multipeermap_iterate (ch->sug_requests,
282 GNUNET_CONTAINER_multipeermap_destroy (ch->sug_requests);
288 * We would like to receive address suggestions for a peer. ATS will
289 * respond with a call to the continuation immediately containing an address or
290 * no address if none is available. ATS can suggest more addresses until we call
291 * #GNUNET_ATS_connectivity_suggest_cancel().
294 * @param peer identity of the peer we need an address for
295 * @param strength how urgent is the need for such a suggestion
296 * @return suggest handle, NULL if a request is already pending
298 struct GNUNET_ATS_ConnectivitySuggestHandle *
299 GNUNET_ATS_connectivity_suggest (struct GNUNET_ATS_ConnectivityHandle *ch,
300 const struct GNUNET_PeerIdentity *peer,
303 struct GNUNET_ATS_ConnectivitySuggestHandle *s;
305 s = GNUNET_new (struct GNUNET_ATS_ConnectivitySuggestHandle);
308 s->strength = strength;
310 GNUNET_CONTAINER_multipeermap_put (ch->sug_requests,
313 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY))
315 LOG (GNUNET_ERROR_TYPE_DEBUG,
316 "Not requesting ATS to suggest address for `%s', request already pending\n",
321 LOG (GNUNET_ERROR_TYPE_DEBUG,
322 "Requesting ATS to suggest address for `%s'\n",
326 (void) transmit_suggestion (ch,
334 * We no longer care about being connected to a peer.
336 * @param sh handle to stop
339 GNUNET_ATS_connectivity_suggest_cancel (struct GNUNET_ATS_ConnectivitySuggestHandle *sh)
341 struct GNUNET_ATS_ConnectivityHandle *ch = sh->ch;
342 struct GNUNET_MQ_Envelope *ev;
343 struct RequestAddressMessage *m;
345 LOG (GNUNET_ERROR_TYPE_DEBUG,
346 "Telling ATS we no longer care for an address for `%s'\n",
347 GNUNET_i2s (&sh->id));
348 GNUNET_assert (GNUNET_OK ==
349 GNUNET_CONTAINER_multipeermap_remove (ch->sug_requests,
357 ev = GNUNET_MQ_msg (m,
358 GNUNET_MESSAGE_TYPE_ATS_REQUEST_ADDRESS_CANCEL);
359 m->strength = htonl (0);
361 GNUNET_MQ_send (ch->mq, ev);
366 /* end of ats_api_connectivity.c */