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22 * @author Christian Grothoff
25 * API that can be used to store naming information on a GNUnet node;
27 * @defgroup namestore Name Store service
28 * Store naming information on a GNUnet node.
30 * Naming information can either be records for which this peer/user is
31 * authoritative, or blocks which are cached, encrypted naming data from other
34 * @see [Documentation](https://gnunet.org/namestore-subsystem)
38 #ifndef GNUNET_NAMESTORE_SERVICE_H
39 #define GNUNET_NAMESTORE_SERVICE_H
41 #include "gnunet_util_lib.h"
42 #include "gnunet_block_lib.h"
43 #include "gnunet_gnsrecord_lib.h"
48 #if 0 /* keep Emacsens' auto-indent happy */
57 struct GNUNET_NAMESTORE_QueueEntry;
60 * Handle to the namestore service.
62 struct GNUNET_NAMESTORE_Handle;
65 * Handle to the namestore zone iterator.
67 struct GNUNET_NAMESTORE_ZoneIterator;
71 * Connect to the namestore service.
73 * @param cfg configuration to use
74 * @return handle to use to access the service
76 struct GNUNET_NAMESTORE_Handle *
77 GNUNET_NAMESTORE_connect (const struct GNUNET_CONFIGURATION_Handle *cfg);
81 * Disconnect from the namestore service (and free associated
82 * resources). Must not be called from within operation callbacks of
85 * @param h handle to the namestore
88 GNUNET_NAMESTORE_disconnect (struct GNUNET_NAMESTORE_Handle *h);
92 * Continuation called to notify client about result of the
96 * @param success #GNUNET_SYSERR on failure (including timeout/queue drop/failure to validate)
97 * #GNUNET_NO if content was already there or not found
98 * #GNUNET_YES (or other positive value) on success
99 * @param emsg NULL on success, otherwise an error message
102 (*GNUNET_NAMESTORE_ContinuationWithStatus) (void *cls,
108 * Store an item in the namestore. If the item is already present,
109 * it is replaced with the new record. Use an empty array to
110 * remove all records under the given name.
112 * The continuation is called after the value has been stored in the
113 * database. Monitors may be notified asynchronously (basically with
114 * a buffer). However, if any monitor is consistently too slow to
115 * keep up with the changes, calling @a cont will be delayed until the
116 * monitors do keep up.
118 * @param h handle to the namestore
119 * @param pkey private key of the zone
120 * @param label name that is being mapped
121 * @param rd_count number of records in the 'rd' array
122 * @param rd array of records with data to store
123 * @param cont continuation to call when done
124 * @param cont_cls closure for @a cont
125 * @return handle to abort the request
127 struct GNUNET_NAMESTORE_QueueEntry *
128 GNUNET_NAMESTORE_records_store (struct GNUNET_NAMESTORE_Handle *h,
130 GNUNET_CRYPTO_EcdsaPrivateKey *pkey,
132 unsigned int rd_count,
133 const struct GNUNET_GNSRECORD_Data *rd,
134 GNUNET_NAMESTORE_ContinuationWithStatus cont,
139 * Process a record that was stored in the namestore.
142 * @param zone private key of the zone
143 * @param label label of the records
144 * @param rd_count number of entries in @a rd array, 0 if label was deleted
145 * @param rd array of records with data to store
148 (*GNUNET_NAMESTORE_RecordMonitor) (void *cls,
150 GNUNET_CRYPTO_EcdsaPrivateKey *zone,
152 unsigned int rd_count,
153 const struct GNUNET_GNSRECORD_Data *rd);
157 * Set the desired nick name for a zone
159 * @param h handle to the namestore
160 * @param pkey private key of the zone
161 * @param nick the nick name to set
162 * @param cont continuation to call when done
163 * @param cont_cls closure for @a cont
164 * @return handle to abort the request
166 struct GNUNET_NAMESTORE_QueueEntry *
167 GNUNET_NAMESTORE_set_nick (struct GNUNET_NAMESTORE_Handle *h,
168 const struct GNUNET_CRYPTO_EcdsaPrivateKey *pkey,
170 GNUNET_NAMESTORE_ContinuationWithStatus cont,
175 * Lookup an item in the namestore.
177 * @param h handle to the namestore
178 * @param pkey private key of the zone
179 * @param label name that is being mapped
180 * @param error_cb function to call on error (i.e. disconnect)
181 * the handle is afterwards invalid
182 * @param error_cb_cls closure for @a error_cb
183 * @param rm function to call with the result (with 0 records if we don't have that label);
184 * the handle is afterwards invalid
185 * @param rm_cls closure for @a rm
186 * @return handle to abort the request
188 struct GNUNET_NAMESTORE_QueueEntry *
189 GNUNET_NAMESTORE_records_lookup (struct GNUNET_NAMESTORE_Handle *h,
191 GNUNET_CRYPTO_EcdsaPrivateKey *pkey,
193 GNUNET_SCHEDULER_TaskCallback error_cb,
195 GNUNET_NAMESTORE_RecordMonitor rm,
200 * Look for an existing PKEY delegation record for a given public key.
201 * Returns at most one result to the processor.
203 * @param h handle to the namestore
204 * @param zone private key of the zone to look up in, never NULL
205 * @param value_zone public key of the target zone (value), never NULL
206 * @param error_cb function to call on error (i.e. disconnect)
207 * the handle is afterwards invalid
208 * @param error_cb_cls closure for @a error_cb
209 * @param proc function to call on the matching records, or with
210 * NULL (rd_count == 0) if there are no matching records;
211 * the handle is afterwards invalid
212 * @param proc_cls closure for @a proc
213 * @return a handle that can be used to
216 struct GNUNET_NAMESTORE_QueueEntry *
217 GNUNET_NAMESTORE_zone_to_name (struct GNUNET_NAMESTORE_Handle *h,
218 const struct GNUNET_CRYPTO_EcdsaPrivateKey *zone,
220 GNUNET_CRYPTO_EcdsaPublicKey *value_zone,
221 GNUNET_SCHEDULER_TaskCallback error_cb,
223 GNUNET_NAMESTORE_RecordMonitor proc,
228 * Cancel a namestore operation. The final callback from the
229 * operation must not have been done yet. Must be called on any
230 * namestore operation that has not yet completed prior to calling
231 * #GNUNET_NAMESTORE_disconnect.
233 * @param qe operation to cancel
236 GNUNET_NAMESTORE_cancel (struct GNUNET_NAMESTORE_QueueEntry *qe);
240 * Starts a new zone iteration (used to periodically PUT all of our
241 * records into our DHT). This MUST lock the `struct GNUNET_NAMESTORE_Handle`
242 * for any other calls than #GNUNET_NAMESTORE_zone_iterator_next() and
243 * #GNUNET_NAMESTORE_zone_iteration_stop. @a proc will be called once
244 * immediately, and then again after
245 * #GNUNET_NAMESTORE_zone_iterator_next() is invoked.
247 * On error (disconnect), @a error_cb will be invoked.
248 * On normal completion, @a finish_cb proc will be
251 * @param h handle to the namestore
252 * @param zone zone to access, NULL for all zones
253 * @param error_cb function to call on error (i.e. disconnect),
254 * the handle is afterwards invalid
255 * @param error_cb_cls closure for @a error_cb
256 * @param proc function to call on each name from the zone; it
257 * will be called repeatedly with a value (if available)
258 * @param proc_cls closure for @a proc
259 * @param finish_cb function to call on completion
260 * the handle is afterwards invalid
261 * @param finish_cb_cls closure for @a finish_cb
262 * @return an iterator handle to use for iteration
264 struct GNUNET_NAMESTORE_ZoneIterator *
265 GNUNET_NAMESTORE_zone_iteration_start (struct GNUNET_NAMESTORE_Handle *h,
267 GNUNET_CRYPTO_EcdsaPrivateKey *zone,
268 GNUNET_SCHEDULER_TaskCallback error_cb,
270 GNUNET_NAMESTORE_RecordMonitor proc,
272 GNUNET_SCHEDULER_TaskCallback finish_cb,
273 void *finish_cb_cls);
277 * Calls the record processor specified in #GNUNET_NAMESTORE_zone_iteration_start
278 * for the next record.
280 * @param it the iterator
281 * @param limit number of records to return to the iterator in one shot
282 * (before #GNUNET_NAMESTORE_zone_iterator_next is to be called again)
285 GNUNET_NAMESTORE_zone_iterator_next (struct GNUNET_NAMESTORE_ZoneIterator *it,
290 * Stops iteration and releases the namestore handle for further calls. Must
291 * be called on any iteration that has not yet completed prior to calling
292 * #GNUNET_NAMESTORE_disconnect.
294 * @param it the iterator
297 GNUNET_NAMESTORE_zone_iteration_stop (struct GNUNET_NAMESTORE_ZoneIterator *it);
301 * Handle for a monitoring activity.
303 struct GNUNET_NAMESTORE_ZoneMonitor;
307 * Begin monitoring a zone for changes. Will first call the @a
308 * monitor function on all existing records in the selected zone(s) if
309 * @a iterate_first is #GNUNET_YES. In any case, we will then call @a
310 * sync_cb, and then afterwards call the @a monitor whenever a record
311 * changes. If the namestore disconnects, the @a error_cb function is
312 * called with a disconnect event. Once the connection is
313 * re-established, the process begins from the start (depending on @a
314 * iterate_first, we will again first do all existing records, then @a
315 * sync, then updates).
317 * @param cfg configuration to use to connect to namestore
318 * @param zone zone to monitor, NULL for all zones
319 * @param iterate_first #GNUNET_YES to first iterate over all existing records,
320 * #GNUNET_NO to only return changes that happen from now on
321 * @param error_cb function to call on error (i.e. disconnect); note that
322 * unlike the other error callbacks in this API, a call to this
323 * function does NOT destroy the monitor handle, it merely signals
324 * that monitoring is down. You need to still explicitly call
325 * #GNUNET_NAMESTORE_zone_monitor_stop().
326 * @param error_cb_cls closure for @a error_cb
327 * @param monitor function to call on zone changes, with an initial limit of 1
328 * @param monitor_cls closure for @a monitor
329 * @param sync_cb function called when we're in sync with the namestore
330 * @param sync_cb_cls closure for @a sync_cb
331 * @return handle to stop monitoring
333 struct GNUNET_NAMESTORE_ZoneMonitor *
334 GNUNET_NAMESTORE_zone_monitor_start (const struct
335 GNUNET_CONFIGURATION_Handle *cfg,
337 GNUNET_CRYPTO_EcdsaPrivateKey *zone,
339 GNUNET_SCHEDULER_TaskCallback error_cb,
341 GNUNET_NAMESTORE_RecordMonitor monitor,
343 GNUNET_SCHEDULER_TaskCallback sync_cb,
348 * Calls the monitor processor specified in #GNUNET_NAMESTORE_zone_monitor_start
349 * for the next record(s). This function is used to allow clients that merely
350 * monitor the NAMESTORE to still throttle namestore operations, so we can be
351 * sure that the monitors can keep up.
353 * Note that #GNUNET_NAMESTORE_records_store() only waits for this
354 * call if the previous limit set by the client was already reached.
355 * Thus, by using a @a limit greater than 1, monitors basically enable
356 * a queue of notifications to be processed asynchronously with some
357 * delay. Note that even with a limit of 1 the
358 * #GNUNET_NAMESTORE_records_store() function will run asynchronously
359 * and the continuation may be invoked before the monitors completed
360 * (or even started) processing the notification. Thus, monitors will
361 * only closely track the current state of the namestore, but not
362 * be involved in the transactions.
364 * @param zm the monitor
365 * @param limit number of records to return to the iterator in one shot
366 * (before #GNUNET_NAMESTORE_zone_monitor_next is to be called again)
369 GNUNET_NAMESTORE_zone_monitor_next (struct GNUNET_NAMESTORE_ZoneMonitor *zm,
374 * Stop monitoring a zone for changes.
376 * @param zm handle to the monitor activity to stop
379 GNUNET_NAMESTORE_zone_monitor_stop (struct GNUNET_NAMESTORE_ZoneMonitor *zm);
382 #if 0 /* keep Emacsens' auto-indent happy */
391 /** @} */ /* end of group */