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/*
* Copyright (C) 2008 The Android Open Source Project
* 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.
*
* 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 LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#ifndef _BIONIC_FUTEX_H
#define _BIONIC_FUTEX_H
#include <errno.h>
#include <linux/futex.h>
#include <stdbool.h>
#include <stddef.h>
#include <sys/cdefs.h>
#include <sys/syscall.h>
#include <unistd.h>
__BEGIN_DECLS
struct timespec;
static inline __always_inline int __futex(volatile void* ftx, int op, int value, const struct timespec* timeout) {
// Our generated syscall assembler sets errno, but our callers (pthread functions) don't want to.
int saved_errno = errno;
int result = syscall(__NR_futex, ftx, op, value, timeout);
if (__predict_false(result == -1)) {
result = -errno;
errno = saved_errno;
}
return result;
}
static inline int __futex_wake(volatile void* ftx, int count) {
return __futex(ftx, FUTEX_WAKE, count, NULL);
}
static inline int __futex_wake_ex(volatile void* ftx, bool shared, int count) {
return __futex(ftx, shared ? FUTEX_WAKE : FUTEX_WAKE_PRIVATE, count, NULL);
}
static inline int __futex_wait(volatile void* ftx, int value, const struct timespec* timeout) {
return __futex(ftx, FUTEX_WAIT, value, timeout);
}
static inline int __futex_wait_ex(volatile void* ftx, bool shared, int value, const struct timespec* timeout) {
return __futex(ftx, shared ? FUTEX_WAIT : FUTEX_WAIT_PRIVATE, value, timeout);
}
__END_DECLS
#endif /* _BIONIC_FUTEX_H */
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