sysdeps/posix/sigintr.c

   1 /* Copyright (C) 1992, 1994, 1996 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 <stddef.h>
  20 #include <signal.h>
  21 #include <errno.h>
  22
  23 /* If INTERRUPT is nonzero, make signal SIG interrupt system calls
  24    (causing them to fail with EINTR); if INTERRUPT is zero, make system
  25    calls be restarted after signal SIG.  */
  26 int
  27 siginterrupt (sig, interrupt)
  28      int sig;
  29      int interrupt;
  30 {
  31 #ifdef  SA_RESTART
  32   extern sigset_t _sigintr;     /* Defined in signal.c.  */
  33   struct sigaction action;
  34
  35   if (__sigaction (sig, (struct sigaction *) NULL, &action) < 0)
  36     return -1;
  37
  38   if (interrupt)
  39     {
  40       __sigaddset (&_sigintr, sig);
  41       action.sa_flags &= ~SA_RESTART;
  42     }
  43   else
  44     {
  45       __sigdelset (&_sigintr, sig);
  46       action.sa_flags |= SA_RESTART;
  47     }
  48
  49   if (__sigaction (sig, &action, (struct sigaction *) NULL) < 0)
  50     return -1;
  51
  52   return 0;
  53 #else
  54   __set_errno (ENOSYS);
  55   return -1;
  56 #endif
  57 }