1 /* Copyright (C) 2004-2022 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 License as
6    published by the Free Software Foundation; either version 2.1 of the
7    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; see the file COPYING.LIB.  If
16    not, see <https://www.gnu.org/licenses/>.  */
17 
18 #ifndef _AIO_MISC_H
19 # include_next <aio_misc.h>
20 # include <limits.h>
21 # include <pthread.h>
22 # include <signal.h>
23 # include <sysdep.h>
24 
25 # define aio_start_notify_thread __aio_start_notify_thread
26 # define aio_create_helper_thread __aio_create_helper_thread
27 
28 extern inline void
__aio_start_notify_thread(void)29 __aio_start_notify_thread (void)
30 {
31   sigset_t ss;
32   sigemptyset (&ss);
33   INTERNAL_SYSCALL_CALL (rt_sigprocmask, SIG_SETMASK, &ss, NULL,
34 			 __NSIG_BYTES);
35 }
36 
37 extern inline int
__aio_create_helper_thread(pthread_t * threadp,void * (* tf)(void *),void * arg)38 __aio_create_helper_thread (pthread_t *threadp, void *(*tf) (void *),
39 			    void *arg)
40 {
41   pthread_attr_t attr;
42 
43   /* Make sure the thread is created detached.  */
44   __pthread_attr_init (&attr);
45   __pthread_attr_setdetachstate (&attr, PTHREAD_CREATE_DETACHED);
46 
47   /* The helper thread needs only very little resources.  */
48   __pthread_attr_setstacksize (&attr, __pthread_get_minstack (&attr));
49 
50   /* Block all signals in the helper thread.  To do this thoroughly we
51      temporarily have to block all signals here.  */
52   sigset_t ss;
53   sigset_t oss;
54   sigfillset (&ss);
55   INTERNAL_SYSCALL_CALL (rt_sigprocmask, SIG_SETMASK, &ss, &oss,
56 			 __NSIG_BYTES);
57 
58   int ret = __pthread_create (threadp, &attr, tf, arg);
59 
60   /* Restore the signal mask.  */
61   INTERNAL_SYSCALL_CALL (rt_sigprocmask, SIG_SETMASK, &oss, NULL,
62 			 __NSIG_BYTES);
63 
64   __pthread_attr_destroy (&attr);
65   return ret;
66 }
67 #endif
68