1 /* Copyright (C) 2002-2022 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
23 int
___pthread_detach(pthread_t th)24 ___pthread_detach (pthread_t th)
25 {
26 struct pthread *pd = (struct pthread *) th;
27
28 /* Make sure the descriptor is valid. */
29 if (INVALID_NOT_TERMINATED_TD_P (pd))
30 /* Not a valid thread handle. */
31 return ESRCH;
32
33 int result = 0;
34
35 /* Mark the thread as detached. */
36 if (atomic_compare_and_exchange_bool_acq (&pd->joinid, pd, NULL))
37 {
38 /* There are two possibilities here. First, the thread might
39 already be detached. In this case we return EINVAL.
40 Otherwise there might already be a waiter. The standard does
41 not mention what happens in this case. */
42 if (IS_DETACHED (pd))
43 result = EINVAL;
44 }
45 else
46 /* Check whether the thread terminated meanwhile. In this case we
47 will just free the TCB. */
48 if ((pd->cancelhandling & EXITING_BITMASK) != 0)
49 /* Note that the code in __free_tcb makes sure each thread
50 control block is freed only once. */
51 __nptl_free_tcb (pd);
52
53 return result;
54 }
55 versioned_symbol (libc, ___pthread_detach, pthread_detach, GLIBC_2_34);
56 libc_hidden_ver (___pthread_detach, __pthread_detach)
57 #ifndef SHARED
58 strong_alias (___pthread_detach, __pthread_detach)
59 #endif
60
61 #if OTHER_SHLIB_COMPAT (libpthread, GLIBC_2_0, GLIBC_2_34)
62 compat_symbol (libc, ___pthread_detach, pthread_detach, GLIBC_2_0);
63 #endif
64