sysdeps/unix/sysv/linux/sigprocmask.c

   1 /* Copyright (C) 1997-2012 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>     /* Neede for string function builtin redirection.  */
  21 #include <unistd.h>
  22
  23 #include <sysdep.h>
  24 #include <sys/syscall.h>
  25 #include <bp-checks.h>
  26
  27 #include <kernel-features.h>
  28
  29
  30 /* Get and/or change the set of blocked signals.  */
  31 int
  32 __sigprocmask (how, set, oset)
  33      int how;
  34      const sigset_t *set;
  35      sigset_t *oset;
  36 {
  37 #ifdef SIGCANCEL
  38   sigset_t local_newmask;
  39
  40   /* The only thing we have to make sure here is that SIGCANCEL and
  41      SIGSETXID are not blocked.  */
  42   if (set != NULL
  43       && (__builtin_expect (__sigismember (set, SIGCANCEL), 0)
  44 # ifdef SIGSETXID
  45           || __builtin_expect (__sigismember (set, SIGSETXID), 0)
  46 # endif
  47           ))
  48     {
  49       local_newmask = *set;
  50       __sigdelset (&local_newmask, SIGCANCEL);
  51 # ifdef SIGSETXID
  52       __sigdelset (&local_newmask, SIGSETXID);
  53 # endif
  54       set = &local_newmask;
  55     }
  56 #endif
  57
  58   return INLINE_SYSCALL (rt_sigprocmask, 4, how, CHECK_SIGSET_NULL_OK (set),
  59                          CHECK_SIGSET_NULL_OK (oset), _NSIG / 8);
  60 }
  61 weak_alias (__sigprocmask, sigprocmask)