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 /* just a little helper function */
79 static void txabort(DB_TXN * tid)
83 ret = tid->abort(tid);
86 syslog(LOG_ERR, "db: txn_abort: %s", db_strerror(ret));
92 /* this one is even more helpful than the last. */
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 /* are you sensing a pattern yet? */
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));
120 static void dbpanic(DB_ENV * env, int errval)
122 syslog(LOG_ERR, "db: PANIC: %s", db_strerror(errval));
126 static void cclose(DBC * cursor)
130 if ((ret = cursor->c_close(cursor))) {
131 syslog(LOG_ERR, "db: c_close: %s", db_strerror(ret));
137 static void bailIfCursor(DBC ** cursors, const char *msg)
141 for (i = 0; i < MAXCDB; i++)
142 if (cursors[i] != NULL) {
143 syslog(LOG_ERR, "db: cursor still in progress on cdb %02x: %s", i, msg);
149 void cdb_check_handles(void)
151 bailIfCursor(TSD->cursors, "in check_handles");
153 if (TSD->tid != NULL) {
154 syslog(LOG_ERR, "db: transaction still in progress!");
161 * Request a checkpoint of the database. Called once per minute by the thread manager.
163 void cdb_checkpoint(void)
167 syslog(LOG_DEBUG, "db: -- checkpoint --");
168 ret = dbenv->txn_checkpoint(dbenv, MAX_CHECKPOINT_KBYTES, MAX_CHECKPOINT_MINUTES, 0);
171 syslog(LOG_ERR, "db: cdb_checkpoint() txn_checkpoint: %s", db_strerror(ret));
175 /* After a successful checkpoint, we can cull the unused logs */
176 if (CtdlGetConfigInt("c_auto_cull")) {
177 ret = dbenv->log_set_config(dbenv, DB_LOG_AUTO_REMOVE, 1);
180 ret = dbenv->log_set_config(dbenv, DB_LOG_AUTO_REMOVE, 0);
186 * Open the various databases we'll be using. Any database which
187 * does not exist should be created. Note that we don't need a
188 * critical section here, because there aren't any active threads
189 * manipulating the database yet.
191 void open_databases(void)
197 int dbversion_major, dbversion_minor, dbversion_patch;
199 syslog(LOG_DEBUG, "db: open_databases() starting");
200 syslog(LOG_DEBUG, "db: Compiled libdb: %s", DB_VERSION_STRING);
201 syslog(LOG_DEBUG, "db: Linked libdb: %s", db_version(&dbversion_major, &dbversion_minor, &dbversion_patch));
202 syslog(LOG_DEBUG, "db: Linked zlib: %s", zlibVersion());
205 * Silently try to create the database subdirectory. If it's
206 * 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 accessrights [%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\n");
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);
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);
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);
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");
277 for (i = 0; i < MAXCDB; ++i) {
279 /* Create a database handle */
280 ret = db_create(&dbp[i], dbenv, 0);
282 syslog(LOG_ERR, "db: db_create: %s", db_strerror(ret));
283 syslog(LOG_ERR, "db: exit code %d", ret);
288 /* Arbitrary names for our tables -- we reference them by
289 * number, so we don't have string names for them.
291 snprintf(dbfilename, sizeof dbfilename, "cdb.%02x", i);
293 ret = dbp[i]->open(dbp[i], NULL, dbfilename, NULL, DB_BTREE, DB_CREATE | DB_AUTO_COMMIT | DB_THREAD, 0600);
295 syslog(LOG_ERR, "db: db_open[%02x]: %s", i, db_strerror(ret));
298 "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.");
300 syslog(LOG_ERR, "db: exit code %d", ret);
308 /* Make sure we own all the files, because in a few milliseconds
309 * we're going to drop root privs.
311 void cdb_chmod_data(void)
315 char filename[PATH_MAX];
317 dp = opendir(ctdl_data_dir);
319 while (d = readdir(dp), d != NULL) {
320 if (d->d_name[0] != '.') {
321 snprintf(filename, sizeof filename, "%s/%s", ctdl_data_dir, d->d_name);
322 syslog(LOG_DEBUG, "db: chmod(%s, 0600) returned %d", filename, chmod(filename, 0600));
323 syslog(LOG_DEBUG, "db: chown(%s, CTDLUID, -1) returned %d",
324 filename, chown(filename, CTDLUID, (-1))
331 syslog(LOG_DEBUG, "db: open_databases() finished");
336 * Close all of the db database files we've opened. This can be done
337 * in a loop, since it's just a bunch of closes.
339 void close_databases(void)
344 syslog(LOG_INFO, "db: performing final checkpoint");
345 if ((ret = dbenv->txn_checkpoint(dbenv, 0, 0, 0))) {
346 syslog(LOG_ERR, "txn_checkpoint: %s", db_strerror(ret));
349 syslog(LOG_INFO, "db: flushing the database logs");
350 if ((ret = dbenv->log_flush(dbenv, NULL))) {
351 syslog(LOG_ERR, "db: log_flush: %s", db_strerror(ret));
354 /* print some statistics... */
356 dbenv->lock_stat_print(dbenv, DB_STAT_ALL);
359 /* close the tables */
360 for (a = 0; a < MAXCDB; ++a) {
361 syslog(LOG_INFO, "db: closing database %02x", a);
362 ret = dbp[a]->close(dbp[a], 0);
364 syslog(LOG_ERR, "db: db_close: %s", db_strerror(ret));
369 /* Close the handle. */
370 ret = dbenv->close(dbenv, 0);
372 syslog(LOG_EMERG, "db: DBENV->close: %s", db_strerror(ret));
378 * Decompress a database item if it was compressed on disk
380 void cdb_decompress_if_necessary(struct cdbdata *cdb)
382 static int magic = COMPRESS_MAGIC;
384 if ((cdb == NULL) || (cdb->ptr == NULL) || (cdb->len < sizeof(magic)) || (memcmp(cdb->ptr, &magic, sizeof(magic)))) {
388 /* At this point we know we're looking at a compressed item. */
390 struct CtdlCompressHeader zheader;
391 char *uncompressed_data;
392 char *compressed_data;
393 uLongf destLen, sourceLen;
396 memset(&zheader, 0, sizeof(struct CtdlCompressHeader));
397 cplen = sizeof(struct CtdlCompressHeader);
398 if (sizeof(struct CtdlCompressHeader) > cdb->len)
400 memcpy(&zheader, cdb->ptr, cplen);
402 compressed_data = cdb->ptr;
403 compressed_data += sizeof(struct CtdlCompressHeader);
405 sourceLen = (uLongf) zheader.compressed_len;
406 destLen = (uLongf) zheader.uncompressed_len;
407 uncompressed_data = malloc(zheader.uncompressed_len);
409 if (uncompress((Bytef *) uncompressed_data,
410 (uLongf *) & destLen, (const Bytef *) compressed_data, (uLong) sourceLen) != Z_OK) {
411 syslog(LOG_EMERG, "db: uncompress() error");
416 cdb->len = (size_t) destLen;
417 cdb->ptr = uncompressed_data;
422 * Store a piece of data. Returns 0 if the operation was successful. If a
423 * key already exists it should be overwritten.
425 int cdb_store(int cdb, const void *ckey, int ckeylen, void *cdata, int cdatalen)
432 struct CtdlCompressHeader zheader;
433 char *compressed_data = NULL;
435 size_t buffer_len = 0;
438 memset(&dkey, 0, sizeof(DBT));
439 memset(&ddata, 0, sizeof(DBT));
441 dkey.data = (void *) ckey;
442 ddata.size = cdatalen;
445 /* Only compress Visit and UseTable records. Everything else is uncompressed. */
446 if ((cdb == CDB_VISIT) || (cdb == CDB_USETABLE)) {
448 zheader.magic = COMPRESS_MAGIC;
449 zheader.uncompressed_len = cdatalen;
450 buffer_len = ((cdatalen * 101) / 100) + 100 + sizeof(struct CtdlCompressHeader);
451 destLen = (uLongf) buffer_len;
452 compressed_data = malloc(buffer_len);
453 if (compress2((Bytef *) (compressed_data + sizeof(struct CtdlCompressHeader)),
454 &destLen, (Bytef *) cdata, (uLongf) cdatalen, 1) != Z_OK) {
455 syslog(LOG_EMERG, "db: compress2() error");
458 zheader.compressed_len = (size_t) destLen;
459 memcpy(compressed_data, &zheader, sizeof(struct CtdlCompressHeader));
460 ddata.size = (size_t) (sizeof(struct CtdlCompressHeader) + zheader.compressed_len);
461 ddata.data = compressed_data;
464 if (TSD->tid != NULL) {
465 ret = dbp[cdb]->put(dbp[cdb], /* db */
466 TSD->tid, /* transaction ID */
472 syslog(LOG_EMERG, "db: cdb_store(%d): %s", cdb, db_strerror(ret));
476 free(compressed_data);
480 bailIfCursor(TSD->cursors, "attempt to write during r/o cursor");
485 if ((ret = dbp[cdb]->put(dbp[cdb], /* db */
486 tid, /* transaction ID */
490 if (ret == DB_LOCK_DEADLOCK) {
494 syslog(LOG_EMERG, "db: cdb_store(%d): %s", cdb, db_strerror(ret));
500 free(compressed_data);
510 * Delete a piece of data. Returns 0 if the operation was successful.
512 int cdb_delete(int cdb, void *key, int keylen)
519 memset(&dkey, 0, sizeof dkey);
523 if (TSD->tid != NULL) {
524 ret = dbp[cdb]->del(dbp[cdb], TSD->tid, &dkey, 0);
526 syslog(LOG_EMERG, "db: cdb_delete(%d): %s", cdb, db_strerror(ret));
527 if (ret != DB_NOTFOUND) {
532 bailIfCursor(TSD->cursors, "attempt to delete during r/o cursor");
537 if ((ret = dbp[cdb]->del(dbp[cdb], tid, &dkey, 0)) && ret != DB_NOTFOUND) {
538 if (ret == DB_LOCK_DEADLOCK) {
542 syslog(LOG_EMERG, "db: cdb_delete(%d): %s", cdb, db_strerror(ret));
553 static DBC *localcursor(int cdb)
558 if (TSD->cursors[cdb] == NULL) {
559 ret = dbp[cdb]->cursor(dbp[cdb], TSD->tid, &curs, 0);
562 ret = TSD->cursors[cdb]->c_dup(TSD->cursors[cdb], &curs, DB_POSITION);
566 syslog(LOG_EMERG, "db: localcursor: %s", db_strerror(ret));
575 * Fetch a piece of data. If not found, returns NULL. Otherwise, it returns
576 * a struct cdbdata which it is the caller's responsibility to free later on
577 * using the cdb_free() routine.
579 struct cdbdata *cdb_fetch(int cdb, const void *key, int keylen)
581 struct cdbdata *tempcdb;
585 memset(&dkey, 0, sizeof(DBT));
587 dkey.data = (void *) key;
589 if (TSD->tid != NULL) {
590 memset(&dret, 0, sizeof(DBT));
591 dret.flags = DB_DBT_MALLOC;
592 ret = dbp[cdb]->get(dbp[cdb], TSD->tid, &dkey, &dret, 0);
597 memset(&dret, 0, sizeof(DBT));
598 dret.flags = DB_DBT_MALLOC;
600 curs = localcursor(cdb);
602 ret = curs->c_get(curs, &dkey, &dret, DB_SET);
605 while (ret == DB_LOCK_DEADLOCK);
609 if ((ret != 0) && (ret != DB_NOTFOUND)) {
610 syslog(LOG_EMERG, "db: cdb_fetch(%d): %s", cdb, db_strerror(ret));
618 tempcdb = (struct cdbdata *) malloc(sizeof(struct cdbdata));
620 if (tempcdb == NULL) {
621 syslog(LOG_EMERG, "db: cdb_fetch: Cannot allocate memory for tempcdb");
623 return NULL; /* make it easier for static analysis... */
625 tempcdb->len = dret.size;
626 tempcdb->ptr = dret.data;
627 cdb_decompress_if_necessary(tempcdb);
634 * Free a cdbdata item.
636 * Note that we only free the 'ptr' portion if it is not NULL. This allows
637 * other code to assume ownership of that memory simply by storing the
638 * pointer elsewhere and then setting 'ptr' to NULL. cdb_free() will then
641 void cdb_free(struct cdbdata *cdb)
650 void cdb_close_cursor(int cdb)
652 if (TSD->cursors[cdb] != NULL) {
653 cclose(TSD->cursors[cdb]);
656 TSD->cursors[cdb] = NULL;
661 * Prepare for a sequential search of an entire database.
662 * (There is guaranteed to be no more than one traversal in
663 * progress per thread at any given time.)
665 void cdb_rewind(int cdb)
669 if (TSD->cursors[cdb] != NULL) {
670 syslog(LOG_EMERG, "db: cdb_rewind: must close cursor on database %d before reopening", cdb);
672 /* cclose(TSD->cursors[cdb]); */
676 * Now initialize the cursor
678 ret = dbp[cdb]->cursor(dbp[cdb], TSD->tid, &TSD->cursors[cdb], 0);
680 syslog(LOG_EMERG, "db: cdb_rewind: db_cursor: %s", db_strerror(ret));
687 * Fetch the next item in a sequential search. Returns a pointer to a
688 * cdbdata structure, or NULL if we've hit the end.
690 struct cdbdata *cdb_next_item(int cdb)
693 struct cdbdata *cdbret;
696 /* Initialize the key/data pair so the flags aren't set. */
697 memset(&key, 0, sizeof(key));
698 memset(&data, 0, sizeof(data));
699 data.flags = DB_DBT_MALLOC;
701 ret = TSD->cursors[cdb]->c_get(TSD->cursors[cdb], &key, &data, DB_NEXT);
704 if (ret != DB_NOTFOUND) {
705 syslog(LOG_EMERG, "db: cdb_next_item(%d): %s", cdb, db_strerror(ret));
708 cdb_close_cursor(cdb);
709 return NULL; /* presumably, end of file */
712 cdbret = (struct cdbdata *) malloc(sizeof(struct cdbdata));
713 cdbret->len = data.size;
714 cdbret->ptr = data.data;
715 cdb_decompress_if_necessary(cdbret);
722 * Transaction-based stuff. I'm writing this as I bake cookies...
724 void cdb_begin_transaction(void)
727 bailIfCursor(TSD->cursors, "can't begin transaction during r/o cursor");
729 if (TSD->tid != NULL) {
730 syslog(LOG_EMERG, "db: cdb_begin_transaction: ERROR: nested transaction");
738 void cdb_end_transaction(void)
742 for (i = 0; i < MAXCDB; i++)
743 if (TSD->cursors[i] != NULL) {
744 syslog(LOG_WARNING, "db: cdb_end_transaction: WARNING: cursor %d still open at transaction end", i);
745 cclose(TSD->cursors[i]);
746 TSD->cursors[i] = NULL;
749 if (TSD->tid == NULL) {
750 syslog(LOG_ERR, "db: cdb_end_transaction: ERROR: txcommit(NULL) !!");
761 * Truncate (delete every record)
763 void cdb_trunc(int cdb)
769 if (TSD->tid != NULL) {
770 syslog(LOG_EMERG, "db: cdb_trunc must not be called in a transaction.");
773 bailIfCursor(TSD->cursors, "attempt to write during r/o cursor");
778 if ((ret = dbp[cdb]->truncate(dbp[cdb], /* db */
779 NULL, /* transaction ID */
780 &count, /* #rows deleted */
782 if (ret == DB_LOCK_DEADLOCK) {
786 syslog(LOG_EMERG, "db: cdb_truncate(%d): %s", cdb, db_strerror(ret));
789 "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.");
801 * compact (defragment) the database , possibly returning space back to the underlying filesystem
803 void cdb_compact(void)
808 syslog(LOG_DEBUG, "db: cdb_compact() started");
809 for (i = 0; i < MAXCDB; i++) {
810 syslog(LOG_DEBUG, "db: compacting database %d", i);
811 ret = dbp[i]->compact(dbp[i], NULL, NULL, NULL, NULL, DB_FREE_SPACE, NULL);
813 syslog(LOG_ERR, "db: compact: %s", db_strerror(ret));
816 syslog(LOG_DEBUG, "db: cdb_compact() finished");
820 // Has an item already been seen (is it in the CDB_USETABLE) ?
821 // Returns 0 if it hasn't, 1 if it has
822 // In either case, writes the item to the database for next time.
823 int CheckIfAlreadySeen(StrBuf *guid)
827 struct cdbdata *cdbut;
829 syslog(LOG_DEBUG, "db: CheckIfAlreadySeen(%s)", ChrPtr(guid));
830 cdbut = cdb_fetch(CDB_USETABLE, SKEY(guid));
836 /* (Re)write the record, to update the timestamp. Zeroing it out makes it compress better. */
837 memset(&ut, 0, sizeof(struct UseTable));
838 memcpy(ut.ut_msgid, SKEY(guid));
839 ut.ut_timestamp = time(NULL);
840 cdb_store(CDB_USETABLE, SKEY(guid), &ut, sizeof(struct UseTable));
845 void cmd_rsen(char *argbuf)
852 struct cdbdata *cdbut;
854 if (CtdlAccessCheck(ac_aide)) {
858 TLen = extract_token(Token, argbuf, 1, '|', sizeof Token);
859 if (strncmp(argbuf, "GET", 3) == 0) {
860 cdbut = cdb_fetch(CDB_USETABLE, Token, TLen);
862 memcpy(&ut, cdbut->ptr, ((cdbut->len > sizeof(struct UseTable)) ? sizeof(struct UseTable) : cdbut->len));
864 cprintf("%d %ld\n", CIT_OK, ut.ut_timestamp);
866 cprintf("%d not found\n", ERROR + NOT_HERE);
869 } else if (strncmp(argbuf, "SET", 3) == 0) {
870 memcpy(ut.ut_msgid, Token, TLen);
871 extract_token(Time, argbuf, 2, '|', sizeof Time);
872 ut.ut_timestamp = atol(Time);
873 cdb_store(CDB_USETABLE, Token, TLen, &ut, sizeof(struct UseTable));
874 cprintf("%d token updated\n", CIT_OK);
875 } else if (strncmp(argbuf, "DEL", 3) == 0) {
876 if (cdb_delete(CDB_USETABLE, Token, TLen))
877 cprintf("%d not found\n", ERROR + NOT_HERE);
879 cprintf("%d deleted.\n", CIT_OK);
882 cprintf("%d Usage: [GET|SET|DEL]|Token|timestamp\n", ERROR);
888 CTDL_MODULE_INIT(database)
891 CtdlRegisterProtoHook(cmd_rsen, "RSEN", "manipulate Aggregators seen database");
894 /* return our module id for the log */