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David Hendricks4b832f52011-01-20 14:28:34 -08001/*
2 * Copyright (C) 2010 Google Inc.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version 2
7 * of the License, or (at your option) any later version.
8 *
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.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
17 *
18 * locks.h: locks are used to preserve atomicity of operations.
19 */
20
21#ifndef LOCKS_H__
22#define LOCKS_H__
23
24/* this is the base key, since we have to pick something global */
25#define IPC_LOCK_KEY (0x67736c00 & 0xfffffc00) /* 22 bits "gsl" */
26
27/* The ordering of the following keys matters a lot. We don't want to reorder
28 * keys and have a new binary dependent on deployed/used because it will break
29 * atomicity of existing users and binaries. In other words, DO NOT REORDER. */
30
31/* this is the "big lock". */
32#define BIGLOCK (IPC_LOCK_KEY + 0)
33
34#endif /* LOCKS_H__ */