2 This file is part of GNUnet
3 (C) 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
8 option) any later version.
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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
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 datastore/plugin_datastore_template.c
23 * @brief template-based datastore backend
24 * @author Christian Grothoff
28 #include "plugin_datastore.h"
32 * Context for all functions in this plugin.
37 * Our execution environment.
39 struct GNUNET_DATASTORE_PluginEnvironment *env;
44 * Get an estimate of how much space the database is
46 * @return number of bytes used on disk
48 static unsigned long long template_plugin_get_size (void *cls)
55 * Store an item in the datastore.
58 * @param key key for the item
59 * @param size number of bytes in data
60 * @param data content stored
61 * @param type type of the content
62 * @param priority priority of the content
63 * @param anonymity anonymity-level for the content
64 * @param expiration expiration time for the content
65 * @param msg set to error message
66 * @return GNUNET_OK on success
69 template_plugin_put (void *cls,
70 const GNUNET_HashCode * key,
76 struct GNUNET_TIME_Absolute expiration,
79 *msg = GNUNET_strdup ("not implemented");
85 * Function invoked on behalf of a "PluginIterator"
86 * asking the database plugin to call the iterator
89 * @param next_cls whatever argument was given
90 * to the PluginIterator as "next_cls".
91 * @param end_it set to GNUNET_YES if we
92 * should terminate the iteration early
93 * (iterator should be still called once more
94 * to signal the end of the iteration).
97 template_next_request (void *next_cls,
104 * Iterate over the results for a particular key
108 * @param key maybe NULL (to match all entries)
109 * @param vhash hash of the value, maybe NULL (to
110 * match all values that have the right key).
111 * Note that for DBlocks there is no difference
112 * betwen key and vhash, but for other blocks
114 * @param type entries of which type are relevant?
115 * Use 0 for any type.
116 * @param iter function to call on each matching value;
117 * will be called once with a NULL value at the end
118 * @param iter_cls closure for iter
121 template_plugin_get (void *cls,
122 const GNUNET_HashCode * key,
123 const GNUNET_HashCode * vhash,
125 PluginIterator iter, void *iter_cls)
131 * Update the priority for a particular key in the datastore. If
132 * the expiration time in value is different than the time found in
133 * the datastore, the higher value should be kept. For the
134 * anonymity level, the lower value is to be used. The specified
135 * priority should be added to the existing priority, ignoring the
138 * Note that it is possible for multiple values to match this put.
139 * In that case, all of the respective values are updated.
141 * @param uid unique identifier of the datum
142 * @param delta by how much should the priority
143 * change? If priority + delta < 0 the
144 * priority should be set to 0 (never go
146 * @param expire new expiration time should be the
147 * MAX of any existing expiration time and
149 * @param msg set to error message
150 * @return GNUNET_OK on success
153 template_plugin_update (void *cls,
155 int delta, struct GNUNET_TIME_Absolute expire,
158 *msg = GNUNET_strdup ("not implemented");
159 return GNUNET_SYSERR;
164 * Select a subset of the items in the datastore and call
165 * the given iterator for each of them.
167 * @param type entries of which type should be considered?
168 * Use 0 for any type.
169 * @param iter function to call on each matching value;
170 * will be called once with a NULL value at the end
171 * @param iter_cls closure for iter
174 template_plugin_iter_low_priority (void *cls,
184 * Select a subset of the items in the datastore and call
185 * the given iterator for each of them.
187 * @param type entries of which type should be considered?
188 * Use 0 for any type.
189 * @param iter function to call on each matching value;
190 * will be called once with a NULL value at the end
191 * @param iter_cls closure for iter
194 template_plugin_iter_zero_anonymity (void *cls,
204 * Select a subset of the items in the datastore and call
205 * the given iterator for each of them.
207 * @param type entries of which type should be considered?
208 * Use 0 for any type.
209 * @param iter function to call on each matching value;
210 * will be called once with a NULL value at the end
211 * @param iter_cls closure for iter
214 template_plugin_iter_ascending_expiration (void *cls,
224 * Select a subset of the items in the datastore and call
225 * the given iterator for each of them.
227 * @param type entries of which type should be considered?
228 * Use 0 for any type.
229 * @param iter function to call on each matching value;
230 * will be called once with a NULL value at the end
231 * @param iter_cls closure for iter
234 template_plugin_iter_migration_order (void *cls,
244 * Select a subset of the items in the datastore and call
245 * the given iterator for each of them.
247 * @param type entries of which type should be considered?
248 * Use 0 for any type.
249 * @param iter function to call on each matching value;
250 * will be called once with a NULL value at the end
251 * @param iter_cls closure for iter
254 template_plugin_iter_all_now (void *cls,
266 template_plugin_drop (void *cls)
272 * Entry point for the plugin.
275 libgnunet_plugin_datastore_template_init (void *cls)
277 struct GNUNET_DATASTORE_PluginEnvironment *env = cls;
278 struct GNUNET_DATASTORE_PluginFunctions *api;
279 struct Plugin *plugin;
281 plugin = GNUNET_malloc (sizeof (struct Plugin));
283 api = GNUNET_malloc (sizeof (struct GNUNET_DATASTORE_PluginFunctions));
285 api->get_size = &template_plugin_get_size;
286 api->put = &template_plugin_put;
287 api->next_request = &template_next_request;
288 api->get = &template_plugin_get;
289 api->update = &template_plugin_update;
290 api->iter_low_priority = &template_plugin_iter_low_priority;
291 api->iter_zero_anonymity = &template_plugin_iter_zero_anonymity;
292 api->iter_ascending_expiration = &template_plugin_iter_ascending_expiration;
293 api->iter_migration_order = &template_plugin_iter_migration_order;
294 api->iter_all_now = &template_plugin_iter_all_now;
295 api->drop = &template_plugin_drop;
296 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO,
297 "template", _("Template database running\n"));
303 * Exit point from the plugin.
306 libgnunet_plugin_datastore_template_done (void *cls)
308 struct GNUNET_DATASTORE_PluginFunctions *api = cls;
309 struct Plugin *plugin = api->cls;
311 GNUNET_free (plugin);
316 /* end of plugin_datastore_template.c */