/* Memory allocation next to an unmapped page.

   Copyright (C) 2017-2018 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/>.  */

#ifndef SUPPORT_NEXT_TO_FAULT_H

#define SUPPORT_NEXT_TO_FAULT_H

#include <sys/cdefs.h>

#include <sys/types.h>

__BEGIN_DECLS

/* The memory region created by next_to_fault_allocate.  */

struct support_next_to_fault

{

  /* The user data.  */

  char *buffer;

  size_t length;

  /* The entire allocated region.  */

  void *region_start;

  size_t region_size;

};

/* Allocate a buffer of SIZE bytes just before a page which is mapped

   with PROT_NONE (so that overrunning the buffer will cause a

   fault).  */

struct support_next_to_fault support_next_to_fault_allocate (size_t size);

/* Deallocate the memory region allocated by

   next_to_fault_allocate.  */

void support_next_to_fault_free (struct support_next_to_fault *);

#endif /* SUPPORT_NEXT_TO_FAULT_H */