/* Copyright (C) 2002-2024 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 "pthreadP.h"
#include <atomic.h>


int
__pthread_setcanceltype (int type, int *oldtype)
{
  if (type < PTHREAD_CANCEL_DEFERRED || type > PTHREAD_CANCEL_ASYNCHRONOUS)
    return EINVAL;

  volatile struct pthread *self = THREAD_SELF;

  int oldval = atomic_load_relaxed (&self->cancelhandling);
  while (1)
    {
      int newval = (type == PTHREAD_CANCEL_ASYNCHRONOUS
		    ? oldval | CANCELTYPE_BITMASK
		    : oldval & ~CANCELTYPE_BITMASK);

      if (oldtype != NULL)
	*oldtype = ((oldval & CANCELTYPE_BITMASK)
		    ? PTHREAD_CANCEL_ASYNCHRONOUS : PTHREAD_CANCEL_DEFERRED);

      if (oldval == newval)
	break;

      if (atomic_compare_exchange_weak_acquire (&self->cancelhandling,
						&oldval, newval))
	{
	  if (cancel_enabled_and_canceled_and_async (newval))
	    {
	      THREAD_SETMEM (self, result, PTHREAD_CANCELED);
	      __do_cancel (PTHREAD_CANCELED);
	    }

	  break;
	}
    }

  return 0;
}
libc_hidden_def (__pthread_setcanceltype)
weak_alias (__pthread_setcanceltype, pthread_setcanceltype)