/* Copyright (C) 2002-2018 Free Software Foundation, Inc.

   This file is part of the GNU C Library.

   Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.

   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 <errno.h>

#include "pthreadP.h"

#include <atomic.h>

int

__pthread_detach (pthread_t th)

{

  struct pthread *pd = (struct pthread *) th;

  /* Make sure the descriptor is valid.  */

  if (INVALID_NOT_TERMINATED_TD_P (pd))

    /* Not a valid thread handle.  */

    return ESRCH;

  int result = 0;

  /* Mark the thread as detached.  */

  if (atomic_compare_and_exchange_bool_acq (&pd->joinid, pd, NULL))

    {

      /* There are two possibilities here.  First, the thread might

	 already be detached.  In this case we return EINVAL.

	 Otherwise there might already be a waiter.  The standard does

	 not mention what happens in this case.  */

      if (IS_DETACHED (pd))

	result = EINVAL;

    }

  else

    /* Check whether the thread terminated meanwhile.  In this case we

       will just free the TCB.  */

    if ((pd->cancelhandling & EXITING_BITMASK) != 0)

      /* Note that the code in __free_tcb makes sure each thread

	 control block is freed only once.  */

      __free_tcb (pd);

  return result;

}

weak_alias (__pthread_detach, pthread_detach)