nptl/pthread_sigmask.c

   1 /* Copyright (C) 2002-2020 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
   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
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the 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; if not, see
  17    <https://www.gnu.org/licenses/>.  */
  18
  19 #include <errno.h>
  20 #include <signal.h>
  21 #include <pthreadP.h>
  22 #include <sysdep.h>
  23
  24
  25 int
  26 pthread_sigmask (int how, const sigset_t *newmask, sigset_t *oldmask)
  27 {
  28   sigset_t local_newmask;
  29
  30   /* The only thing we have to make sure here is that SIGCANCEL and
  31      SIGSETXID is not blocked.  */
  32   if (newmask != NULL
  33       && (__builtin_expect (__sigismember (newmask, SIGCANCEL), 0)
  34           || __builtin_expect (__sigismember (newmask, SIGSETXID), 0)))
  35     {
  36       local_newmask = *newmask;
  37       __sigdelset (&local_newmask, SIGCANCEL);
  38       __sigdelset (&local_newmask, SIGSETXID);
  39       newmask = &local_newmask;
  40     }
  41
  42   /* We know that realtime signals are available if NPTL is used.  */
  43   int result = INTERNAL_SYSCALL_CALL (rt_sigprocmask, how, newmask,
  44                                       oldmask, _NSIG / 8);
  45
  46   return (INTERNAL_SYSCALL_ERROR_P (result)
  47           ? INTERNAL_SYSCALL_ERRNO (result)
  48           : 0);
  49 }