linux-stable-rt/include/linux/eventfd.h

43 lines
1012 B
C

/*
* include/linux/eventfd.h
*
* Copyright (C) 2007 Davide Libenzi <davidel@xmailserver.org>
*
*/
#ifndef _LINUX_EVENTFD_H
#define _LINUX_EVENTFD_H
#ifdef CONFIG_EVENTFD
/* For O_CLOEXEC and O_NONBLOCK */
#include <linux/fcntl.h>
/*
* CAREFUL: Check include/asm-generic/fcntl.h when defining
* new flags, since they might collide with O_* ones. We want
* to re-use O_* flags that couldn't possibly have a meaning
* from eventfd, in order to leave a free define-space for
* shared O_* flags.
*/
#define EFD_SEMAPHORE (1 << 0)
#define EFD_CLOEXEC O_CLOEXEC
#define EFD_NONBLOCK O_NONBLOCK
#define EFD_SHARED_FCNTL_FLAGS (O_CLOEXEC | O_NONBLOCK)
#define EFD_FLAGS_SET (EFD_SHARED_FCNTL_FLAGS | EFD_SEMAPHORE)
struct file *eventfd_fget(int fd);
int eventfd_signal(struct file *file, int n);
#else /* CONFIG_EVENTFD */
#define eventfd_fget(fd) ERR_PTR(-ENOSYS)
static inline int eventfd_signal(struct file *file, int n)
{ return 0; }
#endif /* CONFIG_EVENTFD */
#endif /* _LINUX_EVENTFD_H */