sysdeps/unix/sysv/linux/sigprocmask.c

   1 /* Copyright (C) 1997-2014 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
  26 #include <kernel-features.h>
  27
  28
  29 /* Get and/or change the set of blocked signals.  */
  30 int
  31 __sigprocmask (how, set, oset)
  32      int how;
  33      const sigset_t *set;
  34      sigset_t *oset;
  35 {
  36 #ifdef SIGCANCEL
  37   sigset_t local_newmask;
  38
  39   /* The only thing we have to make sure here is that SIGCANCEL and
  40      SIGSETXID are not blocked.  */
  41   if (set != NULL
  42       && (__builtin_expect (__sigismember (set, SIGCANCEL), 0)
  43 # ifdef SIGSETXID
  44           || __builtin_expect (__sigismember (set, SIGSETXID), 0)
  45 # endif
  46           ))
  47     {
  48       local_newmask = *set;
  49       __sigdelset (&local_newmask, SIGCANCEL);
  50 # ifdef SIGSETXID
  51       __sigdelset (&local_newmask, SIGSETXID);
  52 # endif
  53       set = &local_newmask;
  54     }
  55 #endif
  56
  57   return INLINE_SYSCALL (rt_sigprocmask, 4, how, set, oset, _NSIG / 8);
  58 }
  59 weak_alias (__sigprocmask, sigprocmask)