/* help detect directory cycles efficiently

   Copyright (C) 2003-2004, 2006, 2009-2017 Free Software Foundation, Inc.

   This program is free software: you can redistribute it and/or modify

   it under the terms of the GNU General Public License as published by

   the Free Software Foundation; either version 3 of the License, or

   (at your option) any later version.

   This program 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 General Public License for more details.

   You should have received a copy of the GNU General Public License

   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

/* Written by Jim Meyering */

#ifndef CYCLE_CHECK_H

# define CYCLE_CHECK_H 1

# include <stdint.h>

# include <stdbool.h>

# include "dev-ino.h"

# include "same-inode.h"

struct cycle_check_state

{

  struct dev_ino dev_ino;

  uintmax_t chdir_counter;

  int magic;

};

void cycle_check_init (struct cycle_check_state *state);

bool cycle_check (struct cycle_check_state *state, struct stat const *sb);

# define CYCLE_CHECK_REFLECT_CHDIR_UP(State, SB_dir, SB_subdir) \

  do                                                            \

    {                                                           \

      /* You must call cycle_check at least once before using this macro.  */ \

      if ((State)->chdir_counter == 0)                          \

        abort ();                                               \

      if (SAME_INODE ((State)->dev_ino, SB_subdir))             \

        {                                                       \

          (State)->dev_ino.st_dev = (SB_dir).st_dev;            \

          (State)->dev_ino.st_ino = (SB_dir).st_ino;            \

        }                                                       \

    }                                                           \

  while (0)

#endif