sysdeps/unix/sysv/linux/sigprocmask.c

   1 /* Copyright (C) 1997, 1998 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 Library General Public License as
   6    published by the Free Software Foundation; either version 2 of the
   7    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    Library General Public License for more details.
  13
  14    You should have received a copy of the GNU Library General Public
  15    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  16    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17    Boston, MA 02111-1307, USA.  */
  18
  19 #include <errno.h>
  20 #include <signal.h>
  21 #include <unistd.h>
  22
  23 #include <sysdep.h>
  24 #include <sys/syscall.h>
  25
  26 extern int __syscall_sigprocmask (int, const sigset_t *, sigset_t *);
  27 extern int __syscall_rt_sigprocmask (int, const sigset_t *, sigset_t *,
  28                                      size_t);
  29
  30 /* The variable is shared between all wrappers around signal handling
  31    functions which have RT equivalents.  */
  32 int __libc_missing_rt_sigs;
  33
  34
  35 /* Get and/or change the set of blocked signals.  */
  36 int
  37 __sigprocmask (how, set, oset)
  38      int how;
  39      const sigset_t *set;
  40      sigset_t *oset;
  41 {
  42   /* First try the RT signals.  */
  43   if (!__libc_missing_rt_sigs)
  44     {
  45       /* XXX The size argument hopefully will have to be changed to the
  46          real size of the user-level sigset_t.  */
  47       int saved_errno = errno;
  48       int result = INLINE_SYSCALL (rt_sigprocmask, 4, how, set, oset,
  49                                    _NSIG / 8);
  50
  51       if (result >= 0 || errno != ENOSYS)
  52         return result;
  53
  54       __set_errno (saved_errno);
  55       __libc_missing_rt_sigs = 1;
  56     }
  57
  58   return INLINE_SYSCALL (sigprocmask, 3, how, set, oset);
  59 }
  60 weak_alias (__sigprocmask, sigprocmask)