flashrom/big_lock.h

/* Copyright 2012, Google Inc.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *    * Redistributions of source code must retain the above copyright
 *      notice, this list of conditions and the following disclaimer.
 *    * Redistributions in binary form must reproduce the above
 *      copyright notice, this list of conditions and the following
 *      disclaimer in the documentation and/or other materials provided
 *      with the distribution.
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 *      contributors may be used to endorse or promote products derived
 *      from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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 */

#ifndef BIG_LOCK_H__
#define BIG_LOCK_H__

/*
 * acquire_big_lock  -  acquire global lock
 *
 * returns 0 to indicate lock acquired
 * returns >0 to indicate lock was already held
 * returns <0 to indicate failed to acquire lock
 */
extern int acquire_big_lock(int timeout_secs);

/*
 * release_big_lock  -  release global lock
 *
 * returns 0 if lock was released successfully
 * returns -1 if lock had not been held before the call
 */
extern int release_big_lock(void);

#endif /* BIG_LOCK_H__ */