/* Allocate a new stack.  Mach version.

   Copyright (C) 2000-2018 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 <mach.h>

#include <mach/machine/vm_param.h>

#include <pt-internal.h>

/* The next address to use for stack allocation.  */

static vm_address_t next_stack_base = VM_MIN_ADDRESS;

/* Allocate a new stack of size STACKSIZE.  If successful, store the

   address of the newly allocated stack in *STACKADDR and return 0.

   Otherwise return an error code (EINVAL for an invalid stack size,

   EAGAIN if the system lacked the necessary resources to allocate a

   new stack).  */

int

__pthread_stack_alloc (void **stackaddr, size_t stacksize)

{

  vm_offset_t base;

  int i = 0;

get_stack:

  i++;

  for (base = next_stack_base;

       base < VM_MAX_ADDRESS

       && __vm_allocate (__mach_task_self (), &base,

			 stacksize, FALSE) != KERN_SUCCESS; base += stacksize)

    ;

  if (base >= VM_MAX_ADDRESS)

    {

      if (i == 1)

	{

	  next_stack_base = VM_MIN_ADDRESS;

	  goto get_stack;

	}

      else

	return EAGAIN;

    }

  if (base >= VM_MAX_ADDRESS)

    return EAGAIN;

  next_stack_base = base + stacksize;

  (*stackaddr) = (void *) base;

  return 0;

}