sysdeps/unix/sysv/linux/sigprocmask.c

   1 /* Copyright (C) 1997-2017 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    <http://www.gnu.org/licenses/>.  */
  17
  18 #include <errno.h>
  19 #include <signal.h>
  20 #include <string.h>  /* Needed for string function builtin redirection.  */
  21 #include <unistd.h>
  22
  23 #include <sysdep.h>
  24 #include <sys/syscall.h>
  25
  26 #include <nptl/pthreadP.h>              /* SIGCANCEL, SIGSETXID */
  27
  28
  29 /* Get and/or change the set of blocked signals.  */
  30 int
  31 __sigprocmask (int how, const sigset_t *set, sigset_t *oset)
  32 {
  33 #ifdef SIGCANCEL
  34   sigset_t local_newmask;
  35
  36   /* The only thing we have to make sure here is that SIGCANCEL and
  37      SIGSETXID are not blocked.  */
  38   if (set != NULL
  39       && (__builtin_expect (__sigismember (set, SIGCANCEL), 0)
  40 # ifdef SIGSETXID
  41           || __builtin_expect (__sigismember (set, SIGSETXID), 0)
  42 # endif
  43           ))
  44     {
  45       local_newmask = *set;
  46       __sigdelset (&local_newmask, SIGCANCEL);
  47 # ifdef SIGSETXID
  48       __sigdelset (&local_newmask, SIGSETXID);
  49 # endif
  50       set = &local_newmask;
  51     }
  52 #endif
  53
  54   return INLINE_SYSCALL (rt_sigprocmask, 4, how, set, oset, _NSIG / 8);
  55 }
  56 weak_alias (__sigprocmask, sigprocmask)