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
22
23 int
__pthread_setcanceltype(int type,int * oldtype)24 __pthread_setcanceltype (int type, int *oldtype)
25 {
26 if (type < PTHREAD_CANCEL_DEFERRED || type > PTHREAD_CANCEL_ASYNCHRONOUS)
27 return EINVAL;
28
29 volatile struct pthread *self = THREAD_SELF;
30
31 int oldval = atomic_load_relaxed (&self->cancelhandling);
32 while (1)
33 {
34 int newval = (type == PTHREAD_CANCEL_ASYNCHRONOUS
35 ? oldval | CANCELTYPE_BITMASK
36 : oldval & ~CANCELTYPE_BITMASK);
37
38 if (oldtype != NULL)
39 *oldtype = ((oldval & CANCELTYPE_BITMASK)
40 ? PTHREAD_CANCEL_ASYNCHRONOUS : PTHREAD_CANCEL_DEFERRED);
41
42 if (oldval == newval)
43 break;
44
45 if (atomic_compare_exchange_weak_acquire (&self->cancelhandling,
46 &oldval, newval))
47 {
48 if (cancel_enabled_and_canceled_and_async (newval))
49 {
50 THREAD_SETMEM (self, result, PTHREAD_CANCELED);
51 __do_cancel ();
52 }
53
54 break;
55 }
56 }
57
58 return 0;
59 }
60 libc_hidden_def (__pthread_setcanceltype)
61 weak_alias (__pthread_setcanceltype, pthread_setcanceltype)
62