sysdeps/posix/sigintr.c

   1 /* Copyright (C) 1992-2015 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 <stddef.h>
  19 #include <signal.h>
  20 #include <errno.h>
  21
  22 /* If INTERRUPT is nonzero, make signal SIG interrupt system calls
  23    (causing them to fail with EINTR); if INTERRUPT is zero, make system
  24    calls be restarted after signal SIG.  */
  25 int
  26 siginterrupt (sig, interrupt)
  27      int sig;
  28      int interrupt;
  29 {
  30 #ifdef  SA_RESTART
  31   extern sigset_t _sigintr attribute_hidden;    /* Defined in signal.c.  */
  32   struct sigaction action;
  33
  34   if (__sigaction (sig, (struct sigaction *) NULL, &action) < 0)
  35     return -1;
  36
  37   if (interrupt)
  38     {
  39       __sigaddset (&_sigintr, sig);
  40       action.sa_flags &= ~SA_RESTART;
  41     }
  42   else
  43     {
  44       __sigdelset (&_sigintr, sig);
  45       action.sa_flags |= SA_RESTART;
  46     }
  47
  48   if (__sigaction (sig, &action, (struct sigaction *) NULL) < 0)
  49     return -1;
  50
  51   return 0;
  52 #else
  53   __set_errno (ENOSYS);
  54   return -1;
  55 #endif
  56 }