1 /* Copyright (C) 2002-2023 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
8
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
13
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, see
16 <https://www.gnu.org/licenses/>. */
17
18#include <errno.h>
19#include "pthreadP.h"
20#include <atomic.h>
21#include <shlib-compat.h>
22
23int
24___pthread_key_create (pthread_key_t *key, void (*destr) (void *))
25{
26 /* Find a slot in __pthread_keys which is unused. */
27 for (size_t cnt = 0; cnt < PTHREAD_KEYS_MAX; ++cnt)
28 {
29 uintptr_t seq = __pthread_keys[cnt].seq;
30
31 if (KEY_UNUSED (seq) && KEY_USABLE (seq)
32 /* We found an unused slot. Try to allocate it. */
33 && ! atomic_compare_and_exchange_bool_acq (&__pthread_keys[cnt].seq,
34 seq + 1, seq))
35 {
36 /* Remember the destructor. */
37 __pthread_keys[cnt].destr = destr;
38
39 /* Return the key to the caller. */
40 *key = cnt;
41
42 /* The call succeeded. */
43 return 0;
44 }
45 }
46
47 return EAGAIN;
48}
49versioned_symbol (libc, ___pthread_key_create, __pthread_key_create,
50 GLIBC_2_34);
51libc_hidden_ver (___pthread_key_create, __pthread_key_create)
52
53versioned_symbol (libc, ___pthread_key_create, pthread_key_create,
54 GLIBC_2_34);
55#if OTHER_SHLIB_COMPAT (libpthread, GLIBC_2_0, GLIBC_2_34)
56compat_symbol (libpthread, ___pthread_key_create, __pthread_key_create,
57 GLIBC_2_0);
58compat_symbol (libpthread, ___pthread_key_create, pthread_key_create,
59 GLIBC_2_0);
60#endif
61