/* Check setcontext on the context from makecontext.

   Copyright (C) 2018 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

   <http://www.gnu.org/licenses/>.  */

#include <stdio.h>

#include <stdlib.h>

#include <ucontext.h>

#include <unistd.h>

#include <stdatomic.h>

static ucontext_t ctx[5];

static atomic_int done;

static void

f1 (void)

{

  puts ("start f1");

  if (!done)

    {

      if (getcontext (&ctx[2]) != 0)

	{

	  printf ("%s: getcontext: %m\n", __FUNCTION__);

	  exit (EXIT_FAILURE);

	}

      if (done)

	{

	  puts ("set context in f1");

	  if (setcontext (&ctx[3]) != 0)

	    {

	      printf ("%s: setcontext: %m\n", __FUNCTION__);

	      exit (EXIT_FAILURE);

	    }

	}

    }

  done++;

  puts ("swap contexts in f1");

  if (swapcontext (&ctx[4], &ctx[2]) != 0)

    {

      printf ("%s: setcontext: %m\n", __FUNCTION__);

      exit (EXIT_FAILURE);

    }

  puts ("end f1");

  exit (done == 2 ? EXIT_SUCCESS : EXIT_FAILURE);

}

static int

do_test (void)

{

  char st1[32768];

  puts ("making contexts");

  if (getcontext (&ctx[0]) != 0)

    {

      printf ("%s: getcontext: %m\n", __FUNCTION__);

      exit (EXIT_FAILURE);

    }

  if (getcontext (&ctx[1]) != 0)

    {

      printf ("%s: getcontext: %m\n", __FUNCTION__);

      exit (EXIT_FAILURE);

    }

  ctx[1].uc_stack.ss_sp = st1;

  ctx[1].uc_stack.ss_size = sizeof st1;

  ctx[1].uc_link = &ctx[0];

  makecontext (&ctx[1], (void (*) (void)) f1, 0);

  puts ("swap contexts");

  if (swapcontext (&ctx[3], &ctx[1]) != 0)

    {

      printf ("%s: setcontext: %m\n", __FUNCTION__);

      exit (EXIT_FAILURE);

    }

  if (done != 1)

    exit (EXIT_FAILURE);

  done++;

  puts ("set context");

  if (setcontext (&ctx[4]) != 0)

    {

      printf ("%s: setcontext: %m\n", __FUNCTION__);

      exit (EXIT_FAILURE);

    }

  exit (EXIT_FAILURE);

}

#include <support/test-driver.c>