e7d476dfdf
This patch adds support for the EFD_NONBLOCK flag to eventfd2. The
additional changes needed are minimal.
The following test must be adjusted for architectures other than x86 and
x86-64 and in case the syscall numbers changed.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#include <fcntl.h>
#include <stdio.h>
#include <unistd.h>
#include <sys/syscall.h>
#ifndef __NR_eventfd2
# ifdef __x86_64__
# define __NR_eventfd2 290
# elif defined __i386__
# define __NR_eventfd2 328
# else
# error "need __NR_eventfd2"
# endif
#endif
#define EFD_NONBLOCK O_NONBLOCK
int
main (void)
{
int fd = syscall (__NR_eventfd2, 1, 0);
if (fd == -1)
{
puts ("eventfd2(0) failed");
return 1;
}
int fl = fcntl (fd, F_GETFL);
if (fl == -1)
{
puts ("fcntl failed");
return 1;
}
if (fl & O_NONBLOCK)
{
puts ("eventfd2(0) sets non-blocking mode");
return 1;
}
close (fd);
fd = syscall (__NR_eventfd2, 1, EFD_NONBLOCK);
if (fd == -1)
{
puts ("eventfd2(EFD_NONBLOCK) failed");
return 1;
}
fl = fcntl (fd, F_GETFL);
if (fl == -1)
{
puts ("fcntl failed");
return 1;
}
if ((fl & O_NONBLOCK) == 0)
{
puts ("eventfd2(EFD_NONBLOCK) does not set non-blocking mode");
return 1;
}
close (fd);
puts ("OK");
return 0;
}
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Signed-off-by: Ulrich Drepper <drepper@redhat.com>
Acked-by: Davide Libenzi <davidel@xmailserver.org>
Cc: Michael Kerrisk <mtk.manpages@googlemail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
33 lines
618 B
C
33 lines
618 B
C
/*
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* include/linux/eventfd.h
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*
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* Copyright (C) 2007 Davide Libenzi <davidel@xmailserver.org>
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*
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*/
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#ifndef _LINUX_EVENTFD_H
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#define _LINUX_EVENTFD_H
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#ifdef CONFIG_EVENTFD
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/* For O_CLOEXEC and O_NONBLOCK */
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#include <linux/fcntl.h>
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/* Flags for eventfd2. */
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#define EFD_CLOEXEC O_CLOEXEC
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#define EFD_NONBLOCK O_NONBLOCK
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struct file *eventfd_fget(int fd);
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int eventfd_signal(struct file *file, int n);
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#else /* CONFIG_EVENTFD */
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#define eventfd_fget(fd) ERR_PTR(-ENOSYS)
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static inline int eventfd_signal(struct file *file, int n)
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{ return 0; }
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#endif /* CONFIG_EVENTFD */
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#endif /* _LINUX_EVENTFD_H */
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