glibc/signal/sysv_signal.c

/* Copyright (C) 1991-2019 Free Software Foundation, Inc.
   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library; if not, see
   <https://www.gnu.org/licenses/>.  */

#include <errno.h>
#include <signal.h>

/* Set the handler for the signal SIG to HANDLER,
   returning the old handler, or SIG_ERR on error.  */
__sighandler_t
__sysv_signal (int sig, __sighandler_t handler)
{
  /* Check signal extents to protect __sigismember.  */
  if (handler == SIG_ERR || sig < 1 || sig >= NSIG)
    {
      __set_errno (EINVAL);
      return SIG_ERR;
    }

  __set_errno (ENOSYS);

  return SIG_ERR;
}
weak_alias (__sysv_signal, sysv_signal)

stub_warning (sysv_signal)