1 /* Copyright (C) 2002-2021 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 <setjmp.h>
19 #include <stdlib.h>
20 #include "pthreadP.h"
21 #include <futex-internal.h>
22
23
24 /* The next two functions are similar to pthread_setcanceltype() but
25 more specialized for the use in the cancelable functions like write().
26 They do not need to check parameters etc. These functions must be
27 AS-safe, with the exception of the actual cancellation, because they
28 are called by wrappers around AS-safe functions like write().*/
29 int
__pthread_enable_asynccancel(void)30 __pthread_enable_asynccancel (void)
31 {
32 struct pthread *self = THREAD_SELF;
33
34 int oldval = THREAD_GETMEM (self, canceltype);
35 THREAD_SETMEM (self, canceltype, PTHREAD_CANCEL_ASYNCHRONOUS);
36
37 int ch = THREAD_GETMEM (self, cancelhandling);
38
39 if (self->cancelstate == PTHREAD_CANCEL_ENABLE
40 && (ch & CANCELED_BITMASK)
41 && !(ch & EXITING_BITMASK)
42 && !(ch & TERMINATED_BITMASK))
43 {
44 THREAD_SETMEM (self, result, PTHREAD_CANCELED);
45 __do_cancel ();
46 }
47
48 return oldval;
49 }
libc_hidden_def(__pthread_enable_asynccancel)50 libc_hidden_def (__pthread_enable_asynccancel)
51
52 /* See the comment for __pthread_enable_asynccancel regarding
53 the AS-safety of this function. */
54 void
55 __pthread_disable_asynccancel (int oldtype)
56 {
57 /* If asynchronous cancellation was enabled before we do not have
58 anything to do. */
59 if (oldtype == PTHREAD_CANCEL_ASYNCHRONOUS)
60 return;
61
62 struct pthread *self = THREAD_SELF;
63 self->canceltype = PTHREAD_CANCEL_DEFERRED;
64 }
65 libc_hidden_def (__pthread_disable_asynccancel)
66