blob: be32517ec8e9f95c4ef809dd57eef90574ef5644 [file] [log] [blame]
yuezonghe824eb0c2024-06-27 02:32:26 -07001/* Copyright (C) 2002, 2003, 2006 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3 Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, write to the Free
17 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
18 02111-1307 USA. */
19
20#include <errno.h>
21#include "pthreadP.h"
22#include <atomic.h>
23
24
25int
26attribute_protected
27__pthread_key_create (
28 pthread_key_t *key,
29 void (*destr) (void *))
30{
31 /* Find a slot in __pthread_kyes which is unused. */
32 size_t cnt;
33 for (cnt = 0; cnt < PTHREAD_KEYS_MAX; ++cnt)
34 {
35 uintptr_t seq = __pthread_keys[cnt].seq;
36
37 if (KEY_UNUSED (seq) && KEY_USABLE (seq)
38 /* We found an unused slot. Try to allocate it. */
39 && ! atomic_compare_and_exchange_bool_acq (&__pthread_keys[cnt].seq,
40 seq + 1, seq))
41 {
42 /* Remember the destructor. */
43 __pthread_keys[cnt].destr = destr;
44
45 /* Return the key to the caller. */
46 *key = cnt;
47
48 /* The call succeeded. */
49 return 0;
50 }
51 }
52
53 return EAGAIN;
54}
55strong_alias (__pthread_key_create, pthread_key_create)
56strong_alias (__pthread_key_create, __pthread_key_create_internal)