1  /* Copyright (C) 1992-2023 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     <https://www.gnu.org/licenses/>.  */
      17  
      18  #include <stddef.h>
      19  #include <signal.h>
      20  #include <errno.h>
      21  #include <sigsetops.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 (int sig, int interrupt)
      28  {
      29  #ifdef	SA_RESTART
      30    extern sigset_t _sigintr attribute_hidden;	/* Defined in signal.c.  */
      31    struct sigaction action;
      32  
      33    if (__sigaction (sig, (struct sigaction *) NULL, &action) < 0)
      34      return -1;
      35  
      36    if (interrupt)
      37      {
      38        __sigaddset (&_sigintr, sig);
      39        action.sa_flags &= ~SA_RESTART;
      40      }
      41    else
      42      {
      43        __sigdelset (&_sigintr, sig);
      44        action.sa_flags |= SA_RESTART;
      45      }
      46  
      47    if (__sigaction (sig, &action, (struct sigaction *) NULL) < 0)
      48      return -1;
      49  
      50    return 0;
      51  #else
      52    __set_errno (ENOSYS);
      53    return -1;
      54  #endif
      55  }