sysdeps/posix/sigsetmask.c

   1 /* Copyright (C) 1991, 1994, 1995, 1996, 1997 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
  22 /* Set the mask of blocked signals to MASK, returning the old mask.  */
  23 int
  24 __sigsetmask (int mask)
  25 {
  26   register int sig;
  27   sigset_t set, oset;
  28
  29   if (__sigemptyset (&set) < 0)
  30     return -1;
  31
  32   if (sizeof (mask) == sizeof (set))
  33     *(int *) &set = mask;
  34   else if (sizeof (unsigned long int) == sizeof (set))
  35     *(unsigned long int *) &set = (unsigned int) mask;
  36   else
  37     for (sig = 1; sig < NSIG && sig <= sizeof (mask) * 8; ++sig)
  38       if ((mask & sigmask (sig)) && __sigaddset (&set, sig) < 0)
  39         return -1;
  40
  41   if (__sigprocmask (SIG_SETMASK, &set, &oset) < 0)
  42     return -1;
  43
  44   if (sizeof (mask) == sizeof (oset))
  45     mask = *(int *) &oset;
  46   else if (sizeof (unsigned long int) == sizeof (oset))
  47     mask = *(unsigned long int *) &oset;
  48   else
  49     for (sig = 1, mask = 0; sig < NSIG && sig <= sizeof (mask) * 8; ++sig)
  50       if (__sigismember (&oset, sig))
  51         mask |= sigmask (sig);
  52
  53   return mask;
  54 }
  55
  56 weak_alias (__sigsetmask, sigsetmask)