2 This file is part of GNUnet
3 (C) 2004, 2005, 2006, 2007, 2009 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 2, 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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22 * @file include/gnunet_datastore_service.h
23 * @brief API that can be used manage the
24 * datastore for files stored on a GNUnet node;
25 * note that the datastore is NOT responsible for
26 * on-demand encoding, that is achieved using
27 * a special kind of entry.
28 * @author Christian Grothoff
31 #ifndef GNUNET_DATASTORE_SERVICE_H
32 #define GNUNET_DATASTORE_SERVICE_H
34 #include "gnunet_util_lib.h"
39 #if 0 /* keep Emacsens' auto-indent happy */
46 * Handle to the datastore service.
48 struct GNUNET_DATASTORE_Handle;
52 * Connect to the datastore service.
54 * @param cfg configuration to use
55 * @param sched scheduler to use
56 * @return handle to use to access the service
58 struct GNUNET_DATASTORE_Handle *GNUNET_DATASTORE_connect (struct
59 GNUNET_CONFIGURATION_Handle
62 GNUNET_SCHEDULER_Handle
67 * Disconnect from the datastore service (and free
68 * associated resources).
70 * @param h handle to the datastore
71 * @param drop set to GNUNET_YES to delete all data in datastore (!)
73 void GNUNET_DATASTORE_disconnect (struct GNUNET_DATASTORE_Handle *h,
78 * Continuation called to notify client about result of the
82 * @param success GNUNET_SYSERR on failure
83 * @param msg NULL on success, otherwise an error message
85 typedef void (*GNUNET_DATASTORE_ContinuationWithStatus)(void *cls,
91 * Reserve space in the datastore. This function should be used
92 * to avoid "out of space" failures during a longer sequence of "put"
93 * operations (for example, when a file is being inserted).
95 * @param h handle to the datastore
96 * @param amount how much space (in bytes) should be reserved (for content only)
97 * @param entries how many entries will be created (to calculate per-entry overhead)
98 * @param cont continuation to call when done; "success" will be set to
99 * a positive reservation value if space could be reserved.
100 * @param cont_cls closure for cont
103 GNUNET_DATASTORE_reserve (struct GNUNET_DATASTORE_Handle *h,
106 GNUNET_DATASTORE_ContinuationWithStatus cont,
111 * Store an item in the datastore. If the item is already present,
112 * the priorities are summed up and the higher expiration time and
113 * lower anonymity level is used.
115 * @param h handle to the datastore
116 * @param rid reservation ID to use (from "reserve"); use 0 if no
117 * prior reservation was made
118 * @param key key for the value
119 * @param size number of bytes in data
120 * @param data content stored
121 * @param type type of the content
122 * @param priority priority of the content
123 * @param anonymity anonymity-level for the content
124 * @param expiration expiration time for the content
125 * @param cont continuation to call when done
126 * @param cont_cls closure for cont
129 GNUNET_DATASTORE_put (struct GNUNET_DATASTORE_Handle *h,
131 const GNUNET_HashCode * key,
137 struct GNUNET_TIME_Absolute expiration,
138 GNUNET_DATASTORE_ContinuationWithStatus cont,
143 * Signal that all of the data for which a reservation was made has
144 * been stored and that whatever excess space might have been reserved
145 * can now be released.
147 * @param h handle to the datastore
148 * @param rid reservation ID (value of "success" in original continuation
149 * from the "reserve" function).
150 * @param cont continuation to call when done
151 * @param cont_cls closure for cont
154 GNUNET_DATASTORE_release_reserve (struct GNUNET_DATASTORE_Handle *h,
156 GNUNET_DATASTORE_ContinuationWithStatus cont,
161 * Update a value in the datastore.
163 * @param h handle to the datastore
164 * @param uid identifier for the value
165 * @param priority how much to increase the priority of the value
166 * @param expiration new expiration value should be MAX of existing and this argument
167 * @param cont continuation to call when done
168 * @param cont_cls closure for cont
171 GNUNET_DATASTORE_update (struct GNUNET_DATASTORE_Handle *h,
172 unsigned long long uid,
174 struct GNUNET_TIME_Absolute expiration,
175 GNUNET_DATASTORE_ContinuationWithStatus cont,
180 * An iterator over a set of items stored in the datastore.
183 * @param key key for the content
184 * @param size number of bytes in data
185 * @param data content stored
186 * @param type type of the content
187 * @param priority priority of the content
188 * @param anonymity anonymity-level for the content
189 * @param expiration expiration time for the content
190 * @param uid unique identifier for the datum;
191 * maybe 0 if no unique identifier is available
193 typedef void (*GNUNET_DATASTORE_Iterator) (void *cls,
194 const GNUNET_HashCode * key,
200 struct GNUNET_TIME_Absolute
201 expiration, uint64_t uid);
205 * Iterate over the results for a particular key
208 * @param h handle to the datastore
209 * @param key maybe NULL (to match all entries)
210 * @param type desired type, 0 for any
211 * @param iter function to call on each matching value;
212 * will be called once with a NULL value at the end
213 * @param iter_cls closure for iter
216 GNUNET_DATASTORE_get (struct GNUNET_DATASTORE_Handle *h,
217 const GNUNET_HashCode * key,
219 GNUNET_DATASTORE_Iterator iter, void *iter_cls);
223 * Get a random value from the datastore.
225 * @param h handle to the datastore
226 * @param iter function to call on a random value; it
227 * will be called once with a value (if available)
228 * and always once with a value of NULL.
229 * @param iter_cls closure for iter
232 GNUNET_DATASTORE_get_random (struct GNUNET_DATASTORE_Handle *h,
233 GNUNET_DATASTORE_Iterator iter, void *iter_cls);
237 * Explicitly remove some content from the database.
239 * @param h handle to the datastore
240 * @param key key for the value
241 * @param size number of bytes in data
242 * @param data content stored
243 * @param cont continuation to call when done
244 * @param cont_cls closure for cont
247 GNUNET_DATASTORE_remove (struct GNUNET_DATASTORE_Handle *h,
248 const GNUNET_HashCode *key,
249 uint32_t size, const void *data,
250 GNUNET_DATASTORE_ContinuationWithStatus cont,
254 #if 0 /* keep Emacsens' auto-indent happy */
261 /* end of gnunet_datastore_service.h */