rm_/lib/cycle-check.h
2022-07-28 14:16:50 +08:00

53 lines
1.9 KiB
C

/* help detect directory cycles efficiently
Copyright (C) 2003-2004, 2006, 2009-2022 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 <https://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