/* Support functions handling ptrace_scope.

   Copyright (C) 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 <support/check.h>

#include <support/xstdio.h>

#include <support/xptrace.h>

#include <sys/prctl.h>

int

support_ptrace_scope (void)

{

  int ptrace_scope = -1;

#ifdef __linux__

  /* YAMA may be not enabled.  Otherwise it contains a value from 0 to 3:

     - 0 classic ptrace permissions

     - 1 restricted ptrace

     - 2 admin-only attach

     - 3 no attach  */

  FILE *f = fopen ("/proc/sys/kernel/yama/ptrace_scope", "r");

  if (f != NULL)

    {

      TEST_COMPARE (fscanf (f, "%d", &ptrace_scope), 1);

      xfclose (f);

    }

#endif

  return ptrace_scope;

}