sysdeps/unix/sysv/linux/aio_misc.h

   1 /* Copyright (C) 2004-2017 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Jakub Jelinek <jakub@redhat.com>, 2004.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public License as
   7    published by the Free Software Foundation; either version 2.1 of the
   8    License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; see the file COPYING.LIB.  If
  17    not, see <http://www.gnu.org/licenses/>.  */
  18
  19 #ifndef _AIO_MISC_H
  20 # include_next <aio_misc.h>
  21 # include <limits.h>
  22 # include <pthread.h>
  23 # include <signal.h>
  24 # include <sysdep.h>
  25
  26 # define aio_start_notify_thread __aio_start_notify_thread
  27 # define aio_create_helper_thread __aio_create_helper_thread
  28
  29 extern inline void
  30 __aio_start_notify_thread (void)
  31 {
  32   sigset_t ss;
  33   sigemptyset (&ss);
  34   INTERNAL_SYSCALL_DECL (err);
  35   INTERNAL_SYSCALL (rt_sigprocmask, err, 4, SIG_SETMASK, &ss, NULL, _NSIG / 8);
  36 }
  37
  38 extern inline int
  39 __aio_create_helper_thread (pthread_t *threadp, void *(*tf) (void *),
  40                             void *arg)
  41 {
  42   pthread_attr_t attr;
  43
  44   /* Make sure the thread is created detached.  */
  45   pthread_attr_init (&attr);
  46   pthread_attr_setdetachstate (&attr, PTHREAD_CREATE_DETACHED);
  47
  48   /* The helper thread needs only very little resources.  */
  49   (void) pthread_attr_setstacksize (&attr, __pthread_get_minstack (&attr));
  50
  51   /* Block all signals in the helper thread.  To do this thoroughly we
  52      temporarily have to block all signals here.  */
  53   sigset_t ss;
  54   sigset_t oss;
  55   sigfillset (&ss);
  56   INTERNAL_SYSCALL_DECL (err);
  57   INTERNAL_SYSCALL (rt_sigprocmask, err, 4, SIG_SETMASK, &ss, &oss, _NSIG / 8);
  58
  59   int ret = pthread_create (threadp, &attr, tf, arg);
  60
  61   /* Restore the signal mask.  */
  62   INTERNAL_SYSCALL (rt_sigprocmask, err, 4, SIG_SETMASK, &oss, NULL,
  63                     _NSIG / 8);
  64
  65   (void) pthread_attr_destroy (&attr);
  66   return ret;
  67 }
  68 #endif