sysdeps/mach/hurd/gai_misc.h

   1 /* Copyright (C) 2006-2024 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 <assert.h>
  19 #include <signal.h>
  20 #include <pthread.h>
  21
  22 #define gai_start_notify_thread __gai_start_notify_thread
  23 #define gai_create_helper_thread __gai_create_helper_thread
  24
  25 extern inline void
  26 __gai_start_notify_thread (void)
  27 {
  28   sigset_t ss;
  29   sigemptyset (&ss);
  30   int sigerr __attribute__ ((unused));
  31   sigerr = pthread_sigmask (SIG_SETMASK, &ss, NULL);
  32   assert_perror (sigerr);
  33 }
  34
  35 extern inline int
  36 __gai_create_helper_thread (pthread_t *threadp, void *(*tf) (void *),
  37                             void *arg)
  38 {
  39   pthread_attr_t attr;
  40
  41   /* Make sure the thread is created detached.  */
  42   pthread_attr_init (&attr);
  43   pthread_attr_setdetachstate (&attr, PTHREAD_CREATE_DETACHED);
  44
  45   /* The helper thread needs only very little resources.  */
  46   (void) pthread_attr_setstacksize (&attr, 0x10000);
  47
  48   /* Block all signals in the helper thread.  To do this thoroughly we
  49      temporarily have to block all signals here.  */
  50   sigset_t ss;
  51   sigset_t oss;
  52   sigfillset (&ss);
  53   int sigerr __attribute__ ((unused));
  54   sigerr = pthread_sigmask (SIG_SETMASK, &ss, &oss);
  55   assert_perror (sigerr);
  56
  57   int ret = pthread_create (threadp, &attr, tf, arg);
  58
  59   /* Restore the signal mask.  */
  60   sigerr = pthread_sigmask (SIG_SETMASK, &oss, NULL);
  61   assert_perror (sigerr);
  62
  63   (void) pthread_attr_destroy (&attr);
  64   return ret;
  65 }
  66
  67 #include_next <gai_misc.h>