2 * This file is part of GNUnet
3 * (C) 2013 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 3, or (at your
8 * option) any later version.
10 * GNUnet is distributed in the hope that it will be useful, but
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 peerstore/plugin_peerstore_sqlite.c
23 * @brief sqlite-based peerstore backend
24 * @author Omar Tarabai
28 #include "gnunet_peerstore_plugin.h"
29 #include "gnunet_peerstore_service.h"
30 #include "peerstore.h"
34 * After how many ms "busy" should a DB operation fail for good? A
35 * low value makes sure that we are more responsive to requests
36 * (especially PUTs). A high value guarantees a higher success rate
37 * (SELECTs in iterate can take several seconds despite LIMIT=1).
39 * The default value of 1s should ensure that users do not experience
40 * huge latencies while at the same time allowing operations to
41 * succeed with reasonable probability.
43 #define BUSY_TIMEOUT_MS 1000
46 * Log an error message at log-level 'level' that indicates
47 * a failure of the command 'cmd' on file 'filename'
48 * with the message given by strerror(errno).
50 #define LOG_SQLITE(db, level, cmd) do { GNUNET_log_from (level, "peerstore-sqlite", _("`%s' failed at %s:%d with error: %s\n"), cmd, __FILE__, __LINE__, sqlite3_errmsg(db->dbh)); } while(0)
52 #define LOG(kind,...) GNUNET_log_from (kind, "peerstore-sqlite", __VA_ARGS__)
55 * Context for all functions in this plugin.
61 * Configuration handle
63 const struct GNUNET_CONFIGURATION_Handle *cfg;
71 * Native SQLite database handle.
76 * Precompiled SQL for inserting into peerstoredata
78 sqlite3_stmt *insert_peerstoredata;
83 * @brief Prepare a SQL statement
85 * @param dbh handle to the database
86 * @param sql SQL statement, UTF-8 encoded
87 * @return 0 on success
90 sql_exec (sqlite3 *dbh, const char *sql)
94 result = sqlite3_exec (dbh, sql, NULL, NULL, NULL);
95 LOG (GNUNET_ERROR_TYPE_DEBUG,
96 "Executed `%s' / %d\n", sql, result);
97 if (result != SQLITE_OK)
98 LOG (GNUNET_ERROR_TYPE_ERROR,
99 _("Error executing SQL query: %s\n %s\n"),
100 sqlite3_errmsg (dbh), sql);
105 * @brief Prepare a SQL statement
107 * @param dbh handle to the database
108 * @param sql SQL statement, UTF-8 encoded
109 * @param stmt set to the prepared statement
110 * @return 0 on success
113 sql_prepare (sqlite3 *dbh, const char *sql, sqlite3_stmt **stmt)
118 result = sqlite3_prepare_v2 (dbh, sql, strlen (sql), stmt,
119 (const char **) &tail);
120 LOG (GNUNET_ERROR_TYPE_DEBUG,
121 "Prepared `%s' / %p: %d\n", sql, *stmt, result);
122 if (result != SQLITE_OK)
123 LOG (GNUNET_ERROR_TYPE_ERROR,
124 _("Error preparing SQL query: %s\n %s\n"),
125 sqlite3_errmsg (dbh), sql);
130 * Initialize the database connections and associated
131 * data structures (create tables and indices
132 * as needed as well).
134 * @param plugin the plugin context (state for this module)
135 * @return GNUNET_OK on success
138 database_setup (struct Plugin *plugin)
143 GNUNET_CONFIGURATION_get_value_filename (plugin->cfg, "peerstore-sqlite",
144 "FILENAME", &filename))
146 GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR,
147 "peerstore-sqlite", "FILENAME");
148 return GNUNET_SYSERR;
150 if (GNUNET_OK != GNUNET_DISK_file_test (filename))
152 if (GNUNET_OK != GNUNET_DISK_directory_create_for_file (filename))
155 GNUNET_free (filename);
156 return GNUNET_SYSERR;
159 /* filename should be UTF-8-encoded. If it isn't, it's a bug */
160 plugin->fn = filename;
162 /* Open database and precompile statements */
163 if (SQLITE_OK != sqlite3_open (plugin->fn, &plugin->dbh))
165 LOG (GNUNET_ERROR_TYPE_ERROR,
166 _("Unable to initialize SQLite: %s.\n"),
167 sqlite3_errmsg (plugin->dbh));
168 return GNUNET_SYSERR;
171 sql_exec (plugin->dbh, "PRAGMA temp_store=MEMORY");
172 sql_exec (plugin->dbh, "PRAGMA synchronous=NORMAL");
173 sql_exec (plugin->dbh, "PRAGMA legacy_file_format=OFF");
174 sql_exec (plugin->dbh, "PRAGMA auto_vacuum=INCREMENTAL");
175 sql_exec (plugin->dbh, "PRAGMA encoding=\"UTF-8\"");
176 sql_exec (plugin->dbh, "PRAGMA count_changes=OFF");
177 sql_exec (plugin->dbh, "PRAGMA page_size=4096");
179 sqlite3_busy_timeout (plugin->dbh, BUSY_TIMEOUT_MS);
183 sql_exec (plugin->dbh,
184 "CREATE TABLE IF NOT EXISTS peerstoredata (\n"
185 " sub_system TEXT NOT NULL,\n"
186 " peer_id BLOB NOT NULL,\n"
190 /* Prepare statements */
192 sql_prepare (plugin->dbh,
193 "INSERT INTO peerstoredata (sub_system, peer_id, value) VALUES (?,?,?);",
194 &plugin->insert_peerstoredata);
200 * Shutdown database connection and associate data
202 * @param plugin the plugin context (state for this module)
205 database_shutdown (struct Plugin *plugin)
209 while (NULL != (stmt = sqlite3_next_stmt (plugin->dbh, NULL)))
211 result = sqlite3_finalize (stmt);
212 if (SQLITE_OK != result)
213 LOG (GNUNET_ERROR_TYPE_WARNING,
214 "Failed to close statement %p: %d\n", stmt, result);
216 if (SQLITE_OK != sqlite3_close (plugin->dbh))
217 LOG_SQLITE (plugin, GNUNET_ERROR_TYPE_ERROR, "sqlite3_close");
219 GNUNET_free_non_null (plugin->fn);
223 * Entry point for the plugin.
225 * @param cls The struct GNUNET_CONFIGURATION_Handle.
226 * @return NULL on error, otherwise the plugin context
229 libgnunet_plugin_peerstore_sqlite_init (void *cls)
231 static struct Plugin plugin;
232 const struct GNUNET_CONFIGURATION_Handle *cfg = cls;
233 struct GNUNET_PEERSTORE_PluginFunctions *api;
235 if (NULL != plugin.cfg)
236 return NULL; /* can only initialize once! */
237 memset (&plugin, 0, sizeof (struct Plugin));
239 if (GNUNET_OK != database_setup (&plugin))
241 database_shutdown (&plugin);
244 api = GNUNET_new (struct GNUNET_PEERSTORE_PluginFunctions);
246 LOG(GNUNET_ERROR_TYPE_INFO, "Sqlite plugin is running\n");
251 * Exit point from the plugin.
253 * @param cls The plugin context (as returned by "init")
254 * @return Always NULL
257 libgnunet_plugin_peerstore_sqlite_done (void *cls)
259 struct GNUNET_PEERSTORE_PluginFunctions *api = cls;
260 struct Plugin *plugin = api->cls;
262 database_shutdown (plugin);
265 LOG (GNUNET_ERROR_TYPE_INFO, "Sqlite plugin is finished\n");
270 /* end of plugin_peerstore_sqlite.c */