glibc/nptl/sysdeps/unix/sysv/linux/sem_post.c
Ulrich Drepper 7ba0e52c39 Update.
* sysdeps/powerpc/bits/atomic.h (atomic_increment): Define.
	(atomic_decrement): Define.

	* sysdeps/powerpc/bits/atomic.h: Implement atomic_increment_val and
	atomic_decrement_val.
	* sysdeps/powerpc/powerpc32/bits/atomic.h: Likewise.
	* sysdeps/powerpc/powerpc64/bits/atomic.h: Likewise.

	* csu/tst-atomic.c (do_test): Add tests of atomic_increment_val
	and atomic_decrement_val.
2004-09-08 06:09:02 +00:00

48 lines
1.6 KiB
C

/* sem_post -- post to a POSIX semaphore. Generic futex-using version.
Copyright (C) 2003, 2004 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Jakub Jelinek <jakub@redhat.com>, 2003.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <errno.h>
#include <sysdep.h>
#include <lowlevellock.h>
#include <internaltypes.h>
#include <semaphore.h>
#include <shlib-compat.h>
int
__new_sem_post (sem_t *sem)
{
int *futex = (int *) sem;
int nr = atomic_increment_val (futex);
int err = lll_futex_wake (futex, nr);
if (__builtin_expect (err, 0) < 0)
{
__set_errno (-err);
return -1;
}
return 0;
}
versioned_symbol (libpthread, __new_sem_post, sem_post, GLIBC_2_1);
#if SHLIB_COMPAT (libpthread, GLIBC_2_0, GLIBC_2_1)
strong_alias (__new_sem_post, __old_sem_post)
compat_symbol (libpthread, __old_sem_post, sem_post, GLIBC_2_0);
#endif