sysdeps/posix/sigpause.c

   1 /* Copyright (C) 1991, 92, 94, 95, 96, 97 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 <stddef.h>             /* For NULL.  */
  22
  23 /* Set the mask of blocked signals to MASK,
  24    wait for a signal to arrive, and then restore the mask.  */
  25 int
  26 __sigpause (sig_or_mask, is_sig)
  27      int sig_or_mask;
  28      int is_sig;
  29 {
  30   sigset_t set;
  31   int sig;
  32
  33   if (is_sig != 0)
  34     {
  35       /* The modern X/Open implementation is requested.  */
  36       if (sigprocmask (0, NULL, &set) < 0
  37           /* Yes, we call `sigdelset' and not `__sigdelset'.  */
  38           || sigdelset (&set, sig_or_mask) < 0)
  39         return -1;
  40     }
  41   else
  42     {
  43       if (__sigemptyset (&set) < 0)
  44         return -1;
  45
  46       if (sizeof (sig_or_mask) == sizeof (set))
  47         *(int *) &set = sig_or_mask;
  48       else if (sizeof (unsigned long int) == sizeof (set))
  49         *(unsigned long int *) &set = (unsigned int) sig_or_mask;
  50       else
  51         for (sig = 1; sig < NSIG; ++sig)
  52           if ((sig_or_mask & sigmask (sig)) && __sigaddset (&set, sig) < 0)
  53             return -1;
  54     }
  55
  56   return sigsuspend (&set);
  57 }
  58
  59
  60 /* We have to provide a default version of this function since the
  61    standards demand it.  The version which is a bit more reasonable is
  62    the BSD version.  So make this the default.  */
  63 int __default_sigpause __P ((int mask));
  64 int
  65 __default_sigpause (mask)
  66      int mask;
  67 {
  68   return __sigpause (mask, 0);
  69 }
  70 #undef sigpause
  71 weak_alias (__default_sigpause, sigpause)