glibc/nptl/pthread_key_delete.c

42 lines
1.3 KiB
C

/* Copyright (C) 2002-2017 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 "pthreadP.h"
#include <atomic.h>
int
pthread_key_delete (pthread_key_t key)
{
int result = EINVAL;
if (__glibc_likely (key < PTHREAD_KEYS_MAX))
{
unsigned int seq = __pthread_keys[key].seq;
if (__builtin_expect (! KEY_UNUSED (seq), 1)
&& ! atomic_compare_and_exchange_bool_acq (&__pthread_keys[key].seq,
seq + 1, seq))
/* We deleted a valid key. */
result = 0;
}
return result;
}