2 * Unix SMB/CIFS implementation.
3 * Utils around server_id_db with more dependencies
4 * Copyright (C) Volker Lendecke 2014
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 3 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program. If not, see <http://www.gnu.org/licenses/>.
21 #include "server_id_db_util.h"
23 #include "lib/util/samba_util.h"
25 static int server_id_db_check_exclusive(
26 struct server_id_db
*db
, const char *name
,
27 unsigned num_servers
, struct server_id
*servers
);
29 int server_id_db_set_exclusive(struct server_id_db
*db
, const char *name
)
33 struct server_id
*servers
;
35 ret
= server_id_db_add(db
, name
);
40 ret
= server_id_db_lookup(db
, name
, talloc_tos(),
41 &num_servers
, &servers
);
47 * Remove entries from the server_id_db for processes that have died
48 * and could not clean up. This is racy, as two processes could
49 * simultaneously try to register a name. Both would succeed in the
50 * server_id_db_add call, and both would see their peer active during
51 * the check_exclusive call. Both would get an EEXIST, and nobody
52 * would be able to register itself. But this is okay, as this is
53 * meant to be a cleanup routine, and normally only one daemon should
54 * start up at a time anyway. Getting this "right" would mean we would
55 * have to add locking to server_id_db, or add a dependency on
56 * serverids_exist to server_id_db. Both are too heavy-weight for my
60 ret
= server_id_db_check_exclusive(db
, name
, num_servers
, servers
);
65 server_id_db_remove(db
, name
);
70 static int server_id_db_check_exclusive(
71 struct server_id_db
*db
, const char *name
,
72 unsigned num_servers
, struct server_id
*servers
)
74 struct server_id me
= server_id_db_pid(db
);
77 for (i
=0; i
<num_servers
; i
++) {
80 if (server_id_same_process(&me
, &servers
[i
])) {
82 * I am always around ... :-)
87 if (serverid_exists(&servers
[i
])) {
91 ret
= server_id_db_prune_name(db
, name
, servers
[i
]);