/* Set the default attributes to be used by pthread_create in the process.

   Copyright (C) 2013-2018 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 <errno.h>

#include <stdlib.h>

#include <pthreadP.h>

#include <string.h>

int

pthread_setattr_default_np (const pthread_attr_t *in)

{

  const struct pthread_attr *real_in;

  struct pthread_attr attrs;

  int ret;

  real_in = (struct pthread_attr *) in;

  /* Catch invalid values.  */

  int policy = real_in->schedpolicy;

  ret = check_sched_policy_attr (policy);

  if (ret)

    return ret;

  const struct sched_param *param = &real_in->schedparam;

  if (param->sched_priority > 0)

    {

      ret = check_sched_priority_attr (param->sched_priority, policy);

      if (ret)

	return ret;

    }

  /* stacksize == 0 is fine.  It means that we don't change the current

     value.  */

  if (real_in->stacksize != 0)

    {

      ret = check_stacksize_attr (real_in->stacksize);

      if (ret)

	return ret;

    }

  /* Having a default stack address is wrong.  */

  if (real_in->flags & ATTR_FLAG_STACKADDR)

    return EINVAL;

  attrs = *real_in;

  /* Now take the lock because we start writing into

     __default_pthread_attr.  */

  lll_lock (__default_pthread_attr_lock, LLL_PRIVATE);

  /* Free the cpuset if the input is 0.  Otherwise copy in the cpuset

     contents.  */

  size_t cpusetsize = attrs.cpusetsize;

  if (cpusetsize == 0)

    {

      free (__default_pthread_attr.cpuset);

      __default_pthread_attr.cpuset = NULL;

    }

  else if (cpusetsize == __default_pthread_attr.cpusetsize)

    {

      attrs.cpuset = __default_pthread_attr.cpuset;

      memcpy (attrs.cpuset, real_in->cpuset, cpusetsize);

    }

  else

    {

      /* This may look wrong at first sight, but it isn't.  We're freeing

	 __default_pthread_attr.cpuset and allocating to attrs.cpuset because

	 we'll copy over all of attr to __default_pthread_attr later.  */

      cpu_set_t *newp = realloc (__default_pthread_attr.cpuset,

				 cpusetsize);

      if (newp == NULL)

	{

	  ret = ENOMEM;

	  goto out;

	}

      attrs.cpuset = newp;

      memcpy (attrs.cpuset, real_in->cpuset, cpusetsize);

    }

  /* We don't want to accidentally set the default stacksize to zero.  */

  if (attrs.stacksize == 0)

    attrs.stacksize = __default_pthread_attr.stacksize;

  __default_pthread_attr = attrs;

 out:

  lll_unlock (__default_pthread_attr_lock, LLL_PRIVATE);

  return ret;

}