2 * This is a data store backend for the Citadel server which uses Berkeley DB.
4 * Copyright (c) 1987-2019 by the citadel.org team
6 * This program is open source software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License version 3.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
15 /*****************************************************************************
16 Tunable configuration parameters for the Berkeley DB back end
17 *****************************************************************************/
19 /* Citadel will checkpoint the db at the end of every session, but only if
20 * the specified number of kilobytes has been written, or if the specified
21 * number of minutes has passed, since the last checkpoint.
23 #define MAX_CHECKPOINT_KBYTES 256
24 #define MAX_CHECKPOINT_MINUTES 15
26 /*****************************************************************************/
38 #if DB_VERSION_MAJOR < 5
39 #error Citadel requires Berkeley DB v5.0 or newer. Please upgrade.
42 #include <libcitadel.h>
44 #include "ctdl_module.h"
46 #include "citserver.h"
49 static DB *dbp[MAXCDB]; /* One DB handle for each Citadel database */
50 static DB_ENV *dbenv; /* The DB environment (global) */
55 syslog(LOG_DEBUG, "db: citserver is stopping in order to prevent data loss. uid=%d gid=%d euid=%d egid=%d",
56 getuid(), getgid(), geteuid(), getegid()
62 /* Verbose logging callback */
63 void cdb_verbose_log(const DB_ENV * dbenv, const char *msg)
65 if (!IsEmptyStr(msg)) {
66 syslog(LOG_DEBUG, "db: %s", msg);
71 /* Verbose logging callback */
72 void cdb_verbose_err(const DB_ENV * dbenv, const char *errpfx, const char *msg)
74 syslog(LOG_ERR, "db: %s", msg);
78 /* wrapper for txn_abort() that logs/aborts on error */
79 static void txabort(DB_TXN * tid)
83 ret = tid->abort(tid);
86 syslog(LOG_ERR, "db: txn_abort: %s", db_strerror(ret));
92 /* wrapper for txn_commit() that logs/aborts on error */
93 static void txcommit(DB_TXN * tid)
97 ret = tid->commit(tid, 0);
100 syslog(LOG_ERR, "db: txn_commit: %s", db_strerror(ret));
106 /* wrapper for txn_begin() that logs/aborts on error */
107 static void txbegin(DB_TXN ** tid)
111 ret = dbenv->txn_begin(dbenv, NULL, tid, 0);
114 syslog(LOG_ERR, "db: txn_begin: %s", db_strerror(ret));
121 static void dbpanic(DB_ENV * env, int errval)
123 syslog(LOG_ERR, "db: PANIC: %s", db_strerror(errval));
127 static void cclose(DBC * cursor)
131 if ((ret = cursor->c_close(cursor))) {
132 syslog(LOG_ERR, "db: c_close: %s", db_strerror(ret));
138 static void bailIfCursor(DBC ** cursors, const char *msg)
142 for (i = 0; i < MAXCDB; i++)
143 if (cursors[i] != NULL) {
144 syslog(LOG_ERR, "db: cursor still in progress on cdb %02x: %s", i, msg);
150 void cdb_check_handles(void)
152 bailIfCursor(TSD->cursors, "in check_handles");
154 if (TSD->tid != NULL) {
155 syslog(LOG_ERR, "db: transaction still in progress!");
162 * Request a checkpoint of the database. Called once per minute by the thread manager.
164 void cdb_checkpoint(void)
168 syslog(LOG_DEBUG, "db: -- checkpoint --");
169 ret = dbenv->txn_checkpoint(dbenv, MAX_CHECKPOINT_KBYTES, MAX_CHECKPOINT_MINUTES, 0);
172 syslog(LOG_ERR, "db: cdb_checkpoint() txn_checkpoint: %s", db_strerror(ret));
176 /* After a successful checkpoint, we can cull the unused logs */
177 if (CtdlGetConfigInt("c_auto_cull")) {
178 ret = dbenv->log_set_config(dbenv, DB_LOG_AUTO_REMOVE, 1);
181 ret = dbenv->log_set_config(dbenv, DB_LOG_AUTO_REMOVE, 0);
187 * Open the various databases we'll be using. Any database which
188 * does not exist should be created. Note that we don't need a
189 * critical section here, because there aren't any active threads
190 * manipulating the database yet.
192 void open_databases(void)
198 int dbversion_major, dbversion_minor, dbversion_patch;
200 syslog(LOG_DEBUG, "db: open_databases() starting");
201 syslog(LOG_DEBUG, "db: Compiled libdb: %s", DB_VERSION_STRING);
202 syslog(LOG_DEBUG, "db: Linked libdb: %s", db_version(&dbversion_major, &dbversion_minor, &dbversion_patch));
203 syslog(LOG_DEBUG, "db: Linked zlib: %s", zlibVersion());
206 * Silently try to create the database subdirectory. If it's already there, no problem.
208 if ((mkdir(ctdl_data_dir, 0700) != 0) && (errno != EEXIST)) {
209 syslog(LOG_ERR, "db: unable to create database directory [%s]: %m", ctdl_data_dir);
211 if (chmod(ctdl_data_dir, 0700) != 0) {
212 syslog(LOG_ERR, "db: unable to set database directory permissions [%s]: %m", ctdl_data_dir);
214 if (chown(ctdl_data_dir, CTDLUID, (-1)) != 0) {
215 syslog(LOG_ERR, "db: unable to set the owner for [%s]: %m", ctdl_data_dir);
217 syslog(LOG_DEBUG, "db: Setting up DB environment");
218 // db_env_set_func_yield((int (*)(u_long, u_long))sched_yield);
219 ret = db_env_create(&dbenv, 0);
221 syslog(LOG_ERR, "db: db_env_create: %s", db_strerror(ret));
222 syslog(LOG_ERR, "db: exit code %d", ret);
225 dbenv->set_errpfx(dbenv, "citserver");
226 dbenv->set_paniccall(dbenv, dbpanic);
227 dbenv->set_errcall(dbenv, cdb_verbose_err);
228 dbenv->set_errpfx(dbenv, "ctdl");
229 dbenv->set_msgcall(dbenv, cdb_verbose_log);
230 dbenv->set_verbose(dbenv, DB_VERB_DEADLOCK, 1);
231 dbenv->set_verbose(dbenv, DB_VERB_RECOVERY, 1);
234 * We want to specify the shared memory buffer pool cachesize,
235 * but everything else is the default.
237 ret = dbenv->set_cachesize(dbenv, 0, 64 * 1024, 0);
239 syslog(LOG_ERR, "db: set_cachesize: %s", db_strerror(ret));
240 dbenv->close(dbenv, 0);
241 syslog(LOG_ERR, "db: exit code %d", ret);
245 if ((ret = dbenv->set_lk_detect(dbenv, DB_LOCK_DEFAULT))) {
246 syslog(LOG_ERR, "db: set_lk_detect: %s", db_strerror(ret));
247 dbenv->close(dbenv, 0);
248 syslog(LOG_ERR, "db: exit code %d", ret);
252 flags = DB_CREATE | DB_INIT_MPOOL | DB_PRIVATE | DB_INIT_TXN | DB_INIT_LOCK | DB_THREAD | DB_INIT_LOG;
253 syslog(LOG_DEBUG, "db: dbenv->open(dbenv, %s, %d, 0)", ctdl_data_dir, flags);
254 ret = dbenv->open(dbenv, ctdl_data_dir, flags, 0); // try opening the database cleanly
255 if (ret == DB_RUNRECOVERY) {
256 syslog(LOG_ERR, "db: dbenv->open: %s", db_strerror(ret));
257 syslog(LOG_ERR, "db: attempting recovery...");
259 ret = dbenv->open(dbenv, ctdl_data_dir, flags, 0); // try recovery
261 if (ret == DB_RUNRECOVERY) {
262 syslog(LOG_ERR, "db: dbenv->open: %s", db_strerror(ret));
263 syslog(LOG_ERR, "db: attempting catastrophic recovery...");
264 flags &= ~DB_RECOVER;
265 flags |= DB_RECOVER_FATAL;
266 ret = dbenv->open(dbenv, ctdl_data_dir, flags, 0); // try catastrophic recovery
269 syslog(LOG_ERR, "db: dbenv->open: %s", db_strerror(ret));
270 dbenv->close(dbenv, 0);
271 syslog(LOG_ERR, "db: exit code %d", ret);
275 syslog(LOG_INFO, "db: mounting databases");
276 for (i = 0; i < MAXCDB; ++i) {
277 ret = db_create(&dbp[i], dbenv, 0); // Create a database handle
279 syslog(LOG_ERR, "db: db_create: %s", db_strerror(ret));
280 syslog(LOG_ERR, "db: exit code %d", ret);
284 snprintf(dbfilename, sizeof dbfilename, "cdb.%02x", i); // table names by number
285 ret = dbp[i]->open(dbp[i], NULL, dbfilename, NULL, DB_BTREE, DB_CREATE | DB_AUTO_COMMIT | DB_THREAD, 0600);
287 syslog(LOG_ERR, "db: db_open[%02x]: %s", i, db_strerror(ret));
289 syslog(LOG_ERR, "db: You may need to tune your database; please read http://www.citadel.org/doku.php?id=faq:troubleshooting:out_of_lock_entries for more information.");
291 syslog(LOG_ERR, "db: exit code %d", ret);
299 * Make sure we own all the files, because in a few milliseconds we're going to drop root privs.
301 void cdb_chmod_data(void)
305 char filename[PATH_MAX];
307 dp = opendir(ctdl_data_dir);
309 while (d = readdir(dp), d != NULL) {
310 if (d->d_name[0] != '.') {
311 snprintf(filename, sizeof filename, "%s/%s", ctdl_data_dir, d->d_name);
312 syslog(LOG_DEBUG, "db: chmod(%s, 0600) returned %d", filename, chmod(filename, 0600));
313 syslog(LOG_DEBUG, "db: chown(%s, CTDLUID, -1) returned %d",
314 filename, chown(filename, CTDLUID, (-1))
324 * Close all of the db database files we've opened. This can be done
325 * in a loop, since it's just a bunch of closes.
327 void close_databases(void)
332 syslog(LOG_INFO, "db: performing final checkpoint");
333 if ((ret = dbenv->txn_checkpoint(dbenv, 0, 0, 0))) {
334 syslog(LOG_ERR, "txn_checkpoint: %s", db_strerror(ret));
337 syslog(LOG_INFO, "db: flushing the database logs");
338 if ((ret = dbenv->log_flush(dbenv, NULL))) {
339 syslog(LOG_ERR, "db: log_flush: %s", db_strerror(ret));
343 /* print some statistics... */
344 dbenv->lock_stat_print(dbenv, DB_STAT_ALL);
347 /* close the tables */
348 syslog(LOG_INFO, "db: closing databases");
349 for (i = 0; i < MAXCDB; ++i) {
350 syslog(LOG_INFO, "db: closing database %02x", i);
351 ret = dbp[i]->close(dbp[i], 0);
353 syslog(LOG_ERR, "db: db_close: %s", db_strerror(ret));
358 /* Close the handle. */
359 ret = dbenv->close(dbenv, 0);
361 syslog(LOG_EMERG, "db: DBENV->close: %s", db_strerror(ret));
367 * Decompress a database item if it was compressed on disk
369 void cdb_decompress_if_necessary(struct cdbdata *cdb)
371 static int magic = COMPRESS_MAGIC;
373 if ((cdb == NULL) || (cdb->ptr == NULL) || (cdb->len < sizeof(magic)) || (memcmp(cdb->ptr, &magic, sizeof(magic)))) {
377 /* At this point we know we're looking at a compressed item. */
379 struct CtdlCompressHeader zheader;
380 char *uncompressed_data;
381 char *compressed_data;
382 uLongf destLen, sourceLen;
385 memset(&zheader, 0, sizeof(struct CtdlCompressHeader));
386 cplen = sizeof(struct CtdlCompressHeader);
387 if (sizeof(struct CtdlCompressHeader) > cdb->len) {
390 memcpy(&zheader, cdb->ptr, cplen);
392 compressed_data = cdb->ptr;
393 compressed_data += sizeof(struct CtdlCompressHeader);
395 sourceLen = (uLongf) zheader.compressed_len;
396 destLen = (uLongf) zheader.uncompressed_len;
397 uncompressed_data = malloc(zheader.uncompressed_len);
399 if (uncompress((Bytef *) uncompressed_data,
400 (uLongf *) & destLen, (const Bytef *) compressed_data, (uLong) sourceLen) != Z_OK) {
401 syslog(LOG_EMERG, "db: uncompress() error");
406 cdb->len = (size_t) destLen;
407 cdb->ptr = uncompressed_data;
412 * Store a piece of data. Returns 0 if the operation was successful. If a
413 * key already exists it should be overwritten.
415 int cdb_store(int cdb, const void *ckey, int ckeylen, void *cdata, int cdatalen)
422 struct CtdlCompressHeader zheader;
423 char *compressed_data = NULL;
425 size_t buffer_len = 0;
428 memset(&dkey, 0, sizeof(DBT));
429 memset(&ddata, 0, sizeof(DBT));
431 dkey.data = (void *) ckey;
432 ddata.size = cdatalen;
435 /* Only compress Visit and UseTable records. Everything else is uncompressed. */
436 if ((cdb == CDB_VISIT) || (cdb == CDB_USETABLE)) {
438 zheader.magic = COMPRESS_MAGIC;
439 zheader.uncompressed_len = cdatalen;
440 buffer_len = ((cdatalen * 101) / 100) + 100 + sizeof(struct CtdlCompressHeader);
441 destLen = (uLongf) buffer_len;
442 compressed_data = malloc(buffer_len);
443 if (compress2((Bytef *) (compressed_data + sizeof(struct CtdlCompressHeader)),
444 &destLen, (Bytef *) cdata, (uLongf) cdatalen, 1) != Z_OK) {
445 syslog(LOG_EMERG, "db: compress2() error");
448 zheader.compressed_len = (size_t) destLen;
449 memcpy(compressed_data, &zheader, sizeof(struct CtdlCompressHeader));
450 ddata.size = (size_t) (sizeof(struct CtdlCompressHeader) + zheader.compressed_len);
451 ddata.data = compressed_data;
454 if (TSD->tid != NULL) {
455 ret = dbp[cdb]->put(dbp[cdb], // db
456 TSD->tid, // transaction ID
462 syslog(LOG_EMERG, "db: cdb_store(%d): %s", cdb, db_strerror(ret));
466 free(compressed_data);
470 bailIfCursor(TSD->cursors, "attempt to write during r/o cursor");
475 if ((ret = dbp[cdb]->put(dbp[cdb], /* db */
476 tid, /* transaction ID */
480 if (ret == DB_LOCK_DEADLOCK) {
484 syslog(LOG_EMERG, "db: cdb_store(%d): %s", cdb, db_strerror(ret));
490 free(compressed_data);
500 * Delete a piece of data. Returns 0 if the operation was successful.
502 int cdb_delete(int cdb, void *key, int keylen)
509 memset(&dkey, 0, sizeof dkey);
513 if (TSD->tid != NULL) {
514 ret = dbp[cdb]->del(dbp[cdb], TSD->tid, &dkey, 0);
516 syslog(LOG_EMERG, "db: cdb_delete(%d): %s", cdb, db_strerror(ret));
517 if (ret != DB_NOTFOUND) {
522 bailIfCursor(TSD->cursors, "attempt to delete during r/o cursor");
527 if ((ret = dbp[cdb]->del(dbp[cdb], tid, &dkey, 0)) && ret != DB_NOTFOUND) {
528 if (ret == DB_LOCK_DEADLOCK) {
532 syslog(LOG_EMERG, "db: cdb_delete(%d): %s", cdb, db_strerror(ret));
543 static DBC *localcursor(int cdb)
548 if (TSD->cursors[cdb] == NULL) {
549 ret = dbp[cdb]->cursor(dbp[cdb], TSD->tid, &curs, 0);
552 ret = TSD->cursors[cdb]->c_dup(TSD->cursors[cdb], &curs, DB_POSITION);
556 syslog(LOG_EMERG, "db: localcursor: %s", db_strerror(ret));
565 * Fetch a piece of data. If not found, returns NULL. Otherwise, it returns
566 * a struct cdbdata which it is the caller's responsibility to free later on
567 * using the cdb_free() routine.
569 struct cdbdata *cdb_fetch(int cdb, const void *key, int keylen)
571 struct cdbdata *tempcdb;
575 memset(&dkey, 0, sizeof(DBT));
577 dkey.data = (void *) key;
579 if (TSD->tid != NULL) {
580 memset(&dret, 0, sizeof(DBT));
581 dret.flags = DB_DBT_MALLOC;
582 ret = dbp[cdb]->get(dbp[cdb], TSD->tid, &dkey, &dret, 0); // crashing here
587 memset(&dret, 0, sizeof(DBT));
588 dret.flags = DB_DBT_MALLOC;
589 curs = localcursor(cdb);
590 ret = curs->c_get(curs, &dkey, &dret, DB_SET);
593 while (ret == DB_LOCK_DEADLOCK);
596 if ((ret != 0) && (ret != DB_NOTFOUND)) {
597 syslog(LOG_EMERG, "db: cdb_fetch(%d): %s", cdb, db_strerror(ret));
605 tempcdb = (struct cdbdata *) malloc(sizeof(struct cdbdata));
607 if (tempcdb == NULL) {
608 syslog(LOG_EMERG, "db: cdb_fetch: Cannot allocate memory for tempcdb");
610 return NULL; /* make it easier for static analysis... */
612 tempcdb->len = dret.size;
613 tempcdb->ptr = dret.data;
614 cdb_decompress_if_necessary(tempcdb);
621 * Free a cdbdata item.
623 * Note that we only free the 'ptr' portion if it is not NULL. This allows
624 * other code to assume ownership of that memory simply by storing the
625 * pointer elsewhere and then setting 'ptr' to NULL. cdb_free() will then
628 void cdb_free(struct cdbdata *cdb)
637 void cdb_close_cursor(int cdb)
639 if (TSD->cursors[cdb] != NULL) {
640 cclose(TSD->cursors[cdb]);
643 TSD->cursors[cdb] = NULL;
648 * Prepare for a sequential search of an entire database.
649 * (There is guaranteed to be no more than one traversal in
650 * progress per thread at any given time.)
652 void cdb_rewind(int cdb)
656 if (TSD->cursors[cdb] != NULL) {
657 syslog(LOG_EMERG, "db: cdb_rewind: must close cursor on database %d before reopening", cdb);
659 /* cclose(TSD->cursors[cdb]); */
663 * Now initialize the cursor
665 ret = dbp[cdb]->cursor(dbp[cdb], TSD->tid, &TSD->cursors[cdb], 0);
667 syslog(LOG_EMERG, "db: cdb_rewind: db_cursor: %s", db_strerror(ret));
674 * Fetch the next item in a sequential search. Returns a pointer to a
675 * cdbdata structure, or NULL if we've hit the end.
677 struct cdbdata *cdb_next_item(int cdb)
680 struct cdbdata *cdbret;
683 /* Initialize the key/data pair so the flags aren't set. */
684 memset(&key, 0, sizeof(key));
685 memset(&data, 0, sizeof(data));
686 data.flags = DB_DBT_MALLOC;
688 ret = TSD->cursors[cdb]->c_get(TSD->cursors[cdb], &key, &data, DB_NEXT);
691 if (ret != DB_NOTFOUND) {
692 syslog(LOG_EMERG, "db: cdb_next_item(%d): %s", cdb, db_strerror(ret));
695 cdb_close_cursor(cdb);
696 return NULL; /* presumably, end of file */
699 cdbret = (struct cdbdata *) malloc(sizeof(struct cdbdata));
700 cdbret->len = data.size;
701 cdbret->ptr = data.data;
702 cdb_decompress_if_necessary(cdbret);
709 * Transaction-based stuff. I'm writing this as I bake cookies...
711 void cdb_begin_transaction(void)
714 bailIfCursor(TSD->cursors, "can't begin transaction during r/o cursor");
716 if (TSD->tid != NULL) {
717 syslog(LOG_EMERG, "db: cdb_begin_transaction: ERROR: nested transaction");
725 void cdb_end_transaction(void)
729 for (i = 0; i < MAXCDB; i++)
730 if (TSD->cursors[i] != NULL) {
731 syslog(LOG_WARNING, "db: cdb_end_transaction: WARNING: cursor %d still open at transaction end", i);
732 cclose(TSD->cursors[i]);
733 TSD->cursors[i] = NULL;
736 if (TSD->tid == NULL) {
737 syslog(LOG_ERR, "db: cdb_end_transaction: ERROR: txcommit(NULL) !!");
748 * Truncate (delete every record)
750 void cdb_trunc(int cdb)
756 if (TSD->tid != NULL) {
757 syslog(LOG_EMERG, "db: cdb_trunc must not be called in a transaction.");
760 bailIfCursor(TSD->cursors, "attempt to write during r/o cursor");
765 if ((ret = dbp[cdb]->truncate(dbp[cdb], /* db */
766 NULL, /* transaction ID */
767 &count, /* #rows deleted */
769 if (ret == DB_LOCK_DEADLOCK) {
773 syslog(LOG_EMERG, "db: cdb_truncate(%d): %s", cdb, db_strerror(ret));
776 "db: You may need to tune your database; please read http://www.citadel.org/doku.php?id=faq:troubleshooting:out_of_lock_entries for more information.");
788 * compact (defragment) the database , possibly returning space back to the underlying filesystem
790 void cdb_compact(void)
795 syslog(LOG_DEBUG, "db: cdb_compact() started");
796 for (i = 0; i < MAXCDB; i++) {
797 syslog(LOG_DEBUG, "db: compacting database %d", i);
798 ret = dbp[i]->compact(dbp[i], NULL, NULL, NULL, NULL, DB_FREE_SPACE, NULL);
800 syslog(LOG_ERR, "db: compact: %s", db_strerror(ret));
803 syslog(LOG_DEBUG, "db: cdb_compact() finished");
807 // Has an item already been seen (is it in the CDB_USETABLE) ?
808 // Returns 0 if it hasn't, 1 if it has
809 // In either case, writes the item to the database for next time.
810 int CheckIfAlreadySeen(StrBuf *guid)
814 struct cdbdata *cdbut;
816 syslog(LOG_DEBUG, "db: CheckIfAlreadySeen(%s)", ChrPtr(guid));
817 cdbut = cdb_fetch(CDB_USETABLE, SKEY(guid));
823 /* (Re)write the record, to update the timestamp. Zeroing it out makes it compress better. */
824 memset(&ut, 0, sizeof(struct UseTable));
825 memcpy(ut.ut_msgid, SKEY(guid));
826 ut.ut_timestamp = time(NULL);
827 cdb_store(CDB_USETABLE, SKEY(guid), &ut, sizeof(struct UseTable));
832 void cmd_rsen(char *argbuf)
839 struct cdbdata *cdbut;
841 if (CtdlAccessCheck(ac_aide)) {
845 TLen = extract_token(Token, argbuf, 1, '|', sizeof Token);
846 if (strncmp(argbuf, "GET", 3) == 0) {
847 cdbut = cdb_fetch(CDB_USETABLE, Token, TLen);
849 memcpy(&ut, cdbut->ptr, ((cdbut->len > sizeof(struct UseTable)) ? sizeof(struct UseTable) : cdbut->len));
851 cprintf("%d %ld\n", CIT_OK, ut.ut_timestamp);
853 cprintf("%d not found\n", ERROR + NOT_HERE);
856 } else if (strncmp(argbuf, "SET", 3) == 0) {
857 memcpy(ut.ut_msgid, Token, TLen);
858 extract_token(Time, argbuf, 2, '|', sizeof Time);
859 ut.ut_timestamp = atol(Time);
860 cdb_store(CDB_USETABLE, Token, TLen, &ut, sizeof(struct UseTable));
861 cprintf("%d token updated\n", CIT_OK);
862 } else if (strncmp(argbuf, "DEL", 3) == 0) {
863 if (cdb_delete(CDB_USETABLE, Token, TLen))
864 cprintf("%d not found\n", ERROR + NOT_HERE);
866 cprintf("%d deleted.\n", CIT_OK);
869 cprintf("%d Usage: [GET|SET|DEL]|Token|timestamp\n", ERROR);
875 CTDL_MODULE_INIT(database)
878 CtdlRegisterProtoHook(cmd_rsen, "RSEN", "manipulate Aggregators seen database");
881 /* return our module id for the log */