2 This file is part of GNUnet
3 (C) 2006, 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 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 datacache/plugin_datacache_sqlite.c
23 * @brief sqlite for an implementation of a database backend for the datacache
24 * @author Christian Grothoff
27 #include "gnunet_util_lib.h"
28 #include "gnunet_datacache_plugin.h"
31 #define DEBUG_DATACACHE_SQLITE GNUNET_NO
34 * How much overhead do we assume per entry in the
37 #define OVERHEAD (sizeof(GNUNET_HashCode) + 32)
40 * Context for all functions in this plugin.
45 * Our execution environment.
47 struct GNUNET_DATACACHE_PluginEnvironment *env;
50 * Handle to the sqlite database.
55 * Filename used for the DB.
62 * Log an error message at log-level 'level' that indicates
63 * a failure of the command 'cmd' on file 'filename'
64 * with the message given by strerror(errno).
66 #define LOG_SQLITE(db, level, cmd) do { GNUNET_log(level, _("`%s' failed at %s:%d with error: %s\n"), cmd, __FILE__, __LINE__, sqlite3_errmsg(db)); } while(0)
69 #define SQLITE3_EXEC(db, cmd) do { emsg = NULL; if (SQLITE_OK != sqlite3_exec(db, cmd, NULL, NULL, &emsg)) { GNUNET_log(GNUNET_ERROR_TYPE_ERROR | GNUNET_ERROR_TYPE_BULK, _("`%s' failed at %s:%d with error: %s\n"), "sqlite3_exec", __FILE__, __LINE__, emsg); sqlite3_free(emsg); } } while(0)
73 * @brief Prepare a SQL statement
76 sq_prepare (sqlite3 * dbh, const char *zSql, /* SQL statement, UTF-8 encoded */
77 sqlite3_stmt ** ppStmt)
78 { /* OUT: Statement handle */
80 return sqlite3_prepare (dbh,
82 strlen (zSql), ppStmt, (const char **) &dummy);
87 * Store an item in the datastore.
89 * @param cls closure (our "struct Plugin")
90 * @param key key to store data under
91 * @param size number of bytes in data
92 * @param data data to store
93 * @param type type of the value
94 * @param discard_time when to discard the value in any case
95 * @return 0 on error, number of bytes used otherwise
98 sqlite_plugin_put (void *cls,
99 const GNUNET_HashCode * key,
102 enum GNUNET_BLOCK_Type type,
103 struct GNUNET_TIME_Absolute discard_time)
105 struct Plugin *plugin = cls;
109 #if DEBUG_DATACACHE_SQLITE
110 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
111 "Processing `%s' of %u bytes with key `%4s' and expiration %llums\n",
115 (unsigned long long) GNUNET_TIME_absolute_get_remaining (discard_time).rel_value);
117 dval = (int64_t) discard_time.abs_value;
120 if (sq_prepare (plugin->dbh,
122 "(type, expire, key, value) "
123 "VALUES (?, ?, ?, ?)", &stmt) != SQLITE_OK)
125 GNUNET_log (GNUNET_ERROR_TYPE_ERROR | GNUNET_ERROR_TYPE_BULK,
126 _("`%s' failed at %s:%d with error: %s\n"),
127 "sq_prepare", __FILE__, __LINE__,
128 sqlite3_errmsg (plugin->dbh));
131 if ( (SQLITE_OK != sqlite3_bind_int (stmt, 1, type)) ||
132 (SQLITE_OK != sqlite3_bind_int64 (stmt, 2, dval)) ||
133 (SQLITE_OK != sqlite3_bind_blob (stmt, 3, key, sizeof (GNUNET_HashCode),
134 SQLITE_TRANSIENT)) ||
135 (SQLITE_OK != sqlite3_bind_blob (stmt, 4, data, size, SQLITE_TRANSIENT)))
137 LOG_SQLITE (plugin->dbh,
138 GNUNET_ERROR_TYPE_ERROR | GNUNET_ERROR_TYPE_BULK,
140 sqlite3_finalize (stmt);
143 if (SQLITE_DONE != sqlite3_step (stmt))
145 LOG_SQLITE (plugin->dbh,
146 GNUNET_ERROR_TYPE_ERROR | GNUNET_ERROR_TYPE_BULK,
148 sqlite3_finalize (stmt);
151 if (SQLITE_OK != sqlite3_finalize (stmt))
152 LOG_SQLITE (plugin->dbh,
153 GNUNET_ERROR_TYPE_ERROR | GNUNET_ERROR_TYPE_BULK,
155 return size + OVERHEAD;
160 * Iterate over the results for a particular key
163 * @param cls closure (our "struct Plugin")
165 * @param type entries of which type are relevant?
166 * @param iter maybe NULL (to just count)
167 * @param iter_cls closure for iter
168 * @return the number of results found
171 sqlite_plugin_get (void *cls,
172 const GNUNET_HashCode * key,
173 enum GNUNET_BLOCK_Type type,
174 GNUNET_DATACACHE_Iterator iter,
177 struct Plugin *plugin = cls;
179 struct GNUNET_TIME_Absolute now;
180 struct GNUNET_TIME_Absolute exp;
189 now = GNUNET_TIME_absolute_get ();
190 #if DEBUG_DATACACHE_SQLITE
191 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
192 "Processing `%s' for key `%4s'\n",
196 if (sq_prepare (plugin->dbh,
197 "SELECT count(*) FROM ds090 WHERE key=? AND type=? AND expire >= ?",
200 GNUNET_log (GNUNET_ERROR_TYPE_ERROR | GNUNET_ERROR_TYPE_BULK,
201 _("`%s' failed at %s:%d with error: %s\n"),
202 "sq_prepare", __FILE__, __LINE__,
203 sqlite3_errmsg (plugin->dbh));
206 sqlite3_bind_blob (stmt, 1, key, sizeof (GNUNET_HashCode),
208 sqlite3_bind_int (stmt, 2, type);
209 ntime = (int64_t) now.abs_value;
210 GNUNET_assert (ntime >= 0);
211 sqlite3_bind_int64 (stmt, 3, now.abs_value);
212 if (SQLITE_ROW != sqlite3_step (stmt))
214 LOG_SQLITE (plugin->dbh,
215 GNUNET_ERROR_TYPE_ERROR | GNUNET_ERROR_TYPE_BULK,
217 sqlite3_finalize (stmt);
220 total = sqlite3_column_int (stmt, 0);
221 sqlite3_finalize (stmt);
222 if ( (total == 0) || (iter == NULL) )
226 off = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, total);
229 off = (off + 1) % total;
230 GNUNET_snprintf (scratch,
232 "SELECT value,expire FROM ds090 WHERE key=? AND type=? AND expire >= ? LIMIT 1 OFFSET %u",
234 if (sq_prepare (plugin->dbh, scratch, &stmt) != SQLITE_OK)
236 GNUNET_log (GNUNET_ERROR_TYPE_ERROR | GNUNET_ERROR_TYPE_BULK,
237 _("`%s' failed at %s:%d with error: %s\n"),
238 "sq_prepare", __FILE__, __LINE__,
239 sqlite3_errmsg (plugin->dbh));
242 sqlite3_bind_blob (stmt, 1, key, sizeof (GNUNET_HashCode),
244 sqlite3_bind_int (stmt, 2, type);
245 sqlite3_bind_int64 (stmt, 3, now.abs_value);
246 if (sqlite3_step (stmt) != SQLITE_ROW)
248 size = sqlite3_column_bytes (stmt, 0);
249 dat = sqlite3_column_blob (stmt, 0);
250 exp.abs_value = sqlite3_column_int64 (stmt, 1);
251 ntime = (int64_t) exp.abs_value;
252 if (ntime == INT64_MAX)
253 exp = GNUNET_TIME_UNIT_FOREVER_ABS;
255 if (GNUNET_OK != iter (iter_cls,
262 sqlite3_finalize (stmt);
265 sqlite3_finalize (stmt);
272 * Delete the entry with the lowest expiration value
273 * from the datacache right now.
275 * @param cls closure (our "struct Plugin")
276 * @return GNUNET_OK on success, GNUNET_SYSERR on error
279 sqlite_plugin_del (void *cls)
281 struct Plugin *plugin = cls;
289 #if DEBUG_DATACACHE_SQLITE
290 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
296 if (sq_prepare (plugin->dbh,
297 "SELECT type, key, value FROM ds090 ORDER BY expire ASC LIMIT 1",
300 GNUNET_log (GNUNET_ERROR_TYPE_ERROR | GNUNET_ERROR_TYPE_BULK,
301 _("`%s' failed at %s:%d with error: %s\n"),
302 "sq_prepare", __FILE__, __LINE__, sqlite3_errmsg (plugin->dbh));
304 (void) sqlite3_finalize (stmt);
305 return GNUNET_SYSERR;
307 if (SQLITE_ROW != sqlite3_step (stmt))
309 GNUNET_log (GNUNET_ERROR_TYPE_ERROR | GNUNET_ERROR_TYPE_BULK,
310 _("`%s' failed at %s:%d with error: %s\n"),
311 "sqlite3_step", __FILE__, __LINE__,
312 sqlite3_errmsg (plugin->dbh));
313 (void) sqlite3_finalize (stmt);
314 return GNUNET_SYSERR;
316 dtype = sqlite3_column_int (stmt, 0);
317 GNUNET_break (sqlite3_column_bytes (stmt, 1) == sizeof (GNUNET_HashCode));
318 dsize = sqlite3_column_bytes (stmt, 2);
319 GNUNET_assert (dsize <= sizeof (blob));
320 memcpy (blob, sqlite3_column_blob (stmt, 2), dsize);
321 memcpy (&hc, sqlite3_column_blob (stmt, 1), sizeof (GNUNET_HashCode));
322 if (SQLITE_OK != sqlite3_finalize (stmt))
323 GNUNET_log (GNUNET_ERROR_TYPE_ERROR | GNUNET_ERROR_TYPE_BULK,
324 _("`%s' failed at %s:%d with error: %s\n"),
325 "sqlite3_step", __FILE__, __LINE__,
326 sqlite3_errmsg (plugin->dbh));
327 if (sq_prepare (plugin->dbh,
329 "WHERE key=? AND value=? AND type=?",
330 &dstmt) != SQLITE_OK)
332 GNUNET_log (GNUNET_ERROR_TYPE_ERROR | GNUNET_ERROR_TYPE_BULK,
333 _("`%s' failed at %s:%d with error: %s\n"),
334 "sq_prepare", __FILE__, __LINE__, sqlite3_errmsg (plugin->dbh));
336 (void) sqlite3_finalize (stmt);
337 return GNUNET_SYSERR;
340 sqlite3_bind_blob (dstmt,
342 sizeof (GNUNET_HashCode),
343 SQLITE_TRANSIENT)) ||
345 sqlite3_bind_blob (dstmt,
348 SQLITE_TRANSIENT)) ||
350 sqlite3_bind_int (dstmt, 3, dtype)) )
352 GNUNET_log (GNUNET_ERROR_TYPE_ERROR | GNUNET_ERROR_TYPE_BULK,
353 _("`%s' failed at %s:%d with error: %s\n"),
354 "sqlite3_bind", __FILE__, __LINE__,
355 sqlite3_errmsg (plugin->dbh));
356 (void) sqlite3_finalize (dstmt);
357 return GNUNET_SYSERR;
359 if (sqlite3_step (dstmt) != SQLITE_DONE)
361 GNUNET_log (GNUNET_ERROR_TYPE_ERROR | GNUNET_ERROR_TYPE_BULK,
362 _("`%s' failed at %s:%d with error: %s\n"),
363 "sqlite3_step", __FILE__, __LINE__,
364 sqlite3_errmsg (plugin->dbh));
365 (void) sqlite3_finalize (dstmt);
366 return GNUNET_SYSERR;
368 plugin->env->delete_notify (plugin->env->cls,
371 if (SQLITE_OK != sqlite3_finalize (dstmt))
372 GNUNET_log (GNUNET_ERROR_TYPE_ERROR | GNUNET_ERROR_TYPE_BULK,
373 _("`%s' failed at %s:%d with error: %s\n"),
374 "sqlite3_finalize", __FILE__, __LINE__,
375 sqlite3_errmsg (plugin->dbh));
381 * Entry point for the plugin.
383 * @param cls closure (the "struct GNUNET_DATACACHE_PluginEnvironmnet")
384 * @return the plugin's closure (our "struct Plugin")
387 libgnunet_plugin_datacache_sqlite_init (void *cls)
389 struct GNUNET_DATACACHE_PluginEnvironment *env = cls;
390 struct GNUNET_DATACACHE_PluginFunctions *api;
391 struct Plugin *plugin;
397 fn = GNUNET_DISK_mktemp ("gnunet-datacache");
404 fn_utf8 = GNUNET_STRINGS_to_utf8 (fn, strlen (fn), nl_langinfo (CODESET));
407 fn_utf8 = GNUNET_STRINGS_to_utf8 (fn, strlen (fn), "UTF-8");
409 if (SQLITE_OK != sqlite3_open (fn_utf8, &dbh))
412 GNUNET_free (fn_utf8);
417 SQLITE3_EXEC (dbh, "PRAGMA temp_store=MEMORY");
418 SQLITE3_EXEC (dbh, "PRAGMA locking_mode=EXCLUSIVE");
419 SQLITE3_EXEC (dbh, "PRAGMA journal_mode=OFF");
420 SQLITE3_EXEC (dbh, "PRAGMA synchronous=OFF");
421 SQLITE3_EXEC (dbh, "PRAGMA count_changes=OFF");
422 SQLITE3_EXEC (dbh, "PRAGMA page_size=4092");
424 "CREATE TABLE ds090 ("
425 " type INTEGER NOT NULL DEFAULT 0,"
426 " expire INTEGER NOT NULL DEFAULT 0,"
427 " key BLOB NOT NULL DEFAULT '',"
428 " value BLOB NOT NULL DEFAULT '')");
429 SQLITE3_EXEC (dbh, "CREATE INDEX idx_hashidx ON ds090 (key,type,expire)");
430 plugin = GNUNET_malloc (sizeof (struct Plugin));
433 plugin->fn = fn_utf8;
434 api = GNUNET_malloc (sizeof (struct GNUNET_DATACACHE_PluginFunctions));
436 api->get = &sqlite_plugin_get;
437 api->put = &sqlite_plugin_put;
438 api->del = &sqlite_plugin_del;
439 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO,
440 "sqlite", _("Sqlite datacache running\n"));
443 // explain SELECT type FROM gn090 WHERE NOT EXISTS (SELECT 1 from gn090 WHERE expire < 42 LIMIT 1) OR expire < 42 ORDER BY repl DESC, Random() LIMIT 1;
447 * Exit point from the plugin.
449 * @param cls closure (our "struct Plugin")
453 libgnunet_plugin_datacache_sqlite_done (void *cls)
455 struct GNUNET_DATACACHE_PluginFunctions *api = cls;
456 struct Plugin *plugin = api->cls;
458 #if SQLITE_VERSION_NUMBER >= 3007000
462 #if !WINDOWS || defined(__CYGWIN__)
463 if (0 != UNLINK (plugin->fn))
464 GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_WARNING,
467 GNUNET_free (plugin->fn);
469 result = sqlite3_close (plugin->dbh);
470 #if SQLITE_VERSION_NUMBER >= 3007000
471 if (result == SQLITE_BUSY)
473 GNUNET_log_from (GNUNET_ERROR_TYPE_WARNING,
475 _("Tried to close sqlite without finalizing all prepared statements.\n"));
476 stmt = sqlite3_next_stmt(plugin->dbh, NULL);
480 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
481 "sqlite", "Closing statement %p\n", stmt);
483 result = sqlite3_finalize(stmt);
485 if (result != SQLITE_OK)
486 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
488 "Failed to close statement %p: %d\n", stmt, result);
490 stmt = sqlite3_next_stmt(plugin->dbh, NULL);
492 result = sqlite3_close(plugin->dbh);
495 if (SQLITE_OK != result)
496 LOG_SQLITE (plugin->dbh,
497 GNUNET_ERROR_TYPE_ERROR,
500 #if WINDOWS && !defined(__CYGWIN__)
501 if (0 != UNLINK (plugin->fn))
502 GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_WARNING,
505 GNUNET_free (plugin->fn);
507 GNUNET_free (plugin);
514 /* end of plugin_datacache_sqlite.c */