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/* Copyright (C) 2002-2015 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
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, see
<http://www.gnu.org/licenses/>. */
#include <errno.h>
#include <semaphore.h>
#include <shlib-compat.h>
#include "semaphoreP.h"
#include <kernel-features.h>
/* Returns FUTEX_PRIVATE if pshared is zero and private futexes are supported;
returns FUTEX_SHARED otherwise.
TODO Remove when cleaning up the futex API throughout glibc. */
static __always_inline int
futex_private_if_supported (int pshared)
{
if (pshared != 0)
return LLL_SHARED;
#ifdef __ASSUME_PRIVATE_FUTEX
return LLL_PRIVATE;
#else
return THREAD_GETMEM (THREAD_SELF, header.private_futex)
^ FUTEX_PRIVATE_FLAG;
#endif
}
int
__new_sem_init (sem_t *sem, int pshared, unsigned int value)
{
/* Parameter sanity check. */
if (__glibc_unlikely (value > SEM_VALUE_MAX))
{
__set_errno (EINVAL);
return -1;
}
/* Map to the internal type. */
struct new_sem *isem = (struct new_sem *) sem;
/* Use the values the caller provided. */
#if __HAVE_64B_ATOMICS
isem->data = value;
#else
isem->value = value << SEM_VALUE_SHIFT;
isem->nwaiters = 0;
#endif
isem->private = futex_private_if_supported (pshared);
return 0;
}
versioned_symbol (libpthread, __new_sem_init, sem_init, GLIBC_2_1);
#if SHLIB_COMPAT(libpthread, GLIBC_2_0, GLIBC_2_1)
int
attribute_compat_text_section
__old_sem_init (sem, pshared, value)
sem_t *sem;
int pshared;
unsigned int value;
{
/* Parameter sanity check. */
if (__glibc_unlikely (value > SEM_VALUE_MAX))
{
__set_errno (EINVAL);
return -1;
}
/* Map to the internal type. */
struct old_sem *isem = (struct old_sem *) sem;
/* Use the value the user provided. */
isem->value = value;
/* We cannot store the PSHARED attribute. So we always use the
operations needed for shared semaphores. */
return 0;
}
compat_symbol (libpthread, __old_sem_init, sem_init, GLIBC_2_0);
#endif
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