/* a write style traverse - needs to get the transaction lock to prevent deadlocks WARNING: The data buffer given to the callback fn does NOT meet the alignment guarantees malloc gives you. */ _PUBLIC_ int tdb_traverse(struct tdb_context *tdb, tdb_traverse_func fn, void *private_data) { struct tdb_traverse_lock tl = { NULL, 0, 0, F_WRLCK }; enum tdb_lock_flags lock_flags; int ret; if (tdb->read_only || tdb->traverse_read) { return tdb_traverse_read(tdb, fn, private_data); } lock_flags = TDB_LOCK_WAIT; if (tdb->allrecord_lock.count != 0) { /* * This avoids a deadlock between tdb_lockall() and * tdb_traverse(). See * https://bugzilla.samba.org/show_bug.cgi?id=11381 */ lock_flags = TDB_LOCK_NOWAIT; } if (tdb_transaction_lock(tdb, F_WRLCK, lock_flags)) { return -1; } tdb->traverse_write++; tdb_trace(tdb, "tdb_traverse_start"); ret = tdb_traverse_internal(tdb, fn, private_data, &tl); tdb->traverse_write--; tdb_transaction_unlock(tdb, F_WRLCK); return ret; }
/* a write style traverse - needs to get the transaction lock to prevent deadlocks WARNING: The data buffer given to the callback fn does NOT meet the alignment restrictions malloc gives you. */ int tdb_traverse(struct tdb_context *tdb, tdb_traverse_func fn, void *private_data) { struct tdb_traverse_lock tl = { NULL, 0, 0, F_WRLCK }; int ret; bool in_transaction = (tdb->transaction != NULL); if (tdb->read_only || tdb->traverse_read) { return tdb_traverse_read(tdb, fn, private_data); } if (!in_transaction) { if (tdb_transaction_lock(tdb, F_WRLCK)) { return -1; } } tdb->traverse_write++; ret = tdb_traverse_internal(tdb, fn, private_data, &tl); tdb->traverse_write--; if (!in_transaction) { tdb_transaction_unlock(tdb); } return ret; }
/* a write style traverse - temporarily marks the db read only */ int tdb_traverse_read(struct tdb_context *tdb, tdb_traverse_func fn, void *private_data) { struct tdb_traverse_lock tl = { NULL, 0, 0, F_RDLCK }; int ret; bool in_transaction = (tdb->transaction != NULL); /* we need to get a read lock on the transaction lock here to cope with the lock ordering semantics of solaris10 */ if (!in_transaction) { if (tdb_transaction_lock(tdb, F_RDLCK)) { return -1; } } tdb->traverse_read++; ret = tdb_traverse_internal(tdb, fn, private_data, &tl); tdb->traverse_read--; if (!in_transaction) { tdb_transaction_unlock(tdb); } return ret; }
/* a read style traverse - temporarily marks the db read only */ _PUBLIC_ int tdb_traverse_read(struct tdb_context *tdb, tdb_traverse_func fn, void *private_data) { struct tdb_traverse_lock tl = { NULL, 0, 0, F_RDLCK }; int ret; /* we need to get a read lock on the transaction lock here to cope with the lock ordering semantics of solaris10 */ if (tdb_transaction_lock(tdb, F_RDLCK, TDB_LOCK_WAIT)) { return -1; } tdb->traverse_read++; tdb_trace(tdb, "tdb_traverse_read_start"); ret = tdb_traverse_internal(tdb, fn, private_data, &tl); tdb->traverse_read--; tdb_transaction_unlock(tdb, F_RDLCK); return ret; }
/* a write style traverse - needs to get the transaction lock to prevent deadlocks WARNING: The data buffer given to the callback fn does NOT meet the alignment guarantees malloc gives you. */ _PUBLIC_ int tdb_traverse(struct tdb_context *tdb, tdb_traverse_func fn, void *private_data) { struct tdb_traverse_lock tl = { NULL, 0, 0, F_WRLCK }; int ret; if (tdb->read_only || tdb->traverse_read) { return tdb_traverse_read(tdb, fn, private_data); } if (tdb_transaction_lock(tdb, F_WRLCK, TDB_LOCK_WAIT)) { return -1; } tdb->traverse_write++; tdb_trace(tdb, "tdb_traverse_start"); ret = tdb_traverse_internal(tdb, fn, private_data, &tl); tdb->traverse_write--; tdb_transaction_unlock(tdb, F_WRLCK); return ret; }
_PUBLIC_ int tdb_transaction_write_lock_mark(struct tdb_context *tdb) { return tdb_transaction_lock(tdb, F_WRLCK, TDB_LOCK_MARK_ONLY); }