/* help detect directory cycles efficiently
- Copyright (C) 2003, 2004 Free Software Foundation, Inc.
+ Copyright (C) 2003-2006, 2009-2013 Free Software Foundation, Inc.
- This program is free software; you can redistribute it and/or modify
+ 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 2, or (at your option)
- any later version.
+ 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
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
- along with this program; see the file COPYING.
- If not, write to the Free Software Foundation,
- 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
/* Written by Jim Meyering */
-#if HAVE_CONFIG_H
-# include <config.h>
-#endif
+#include <config.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <stdbool.h>
#include "cycle-check.h"
-#include "xalloc.h"
-
-#define SAME_INODE(Stat_buf_1, Stat_buf_2) \
- ((Stat_buf_1).st_ino == (Stat_buf_2).st_ino \
- && (Stat_buf_1).st_dev == (Stat_buf_2).st_dev)
#define CC_MAGIC 9827862
/* Return true if I is a power of 2, or is zero. */
-static inline bool
+static bool
is_zero_or_power_of_two (uintmax_t i)
{
return (i & (i - 1)) == 0;
descending chdir call, with SB corresponding to the chdir operand.
If SB corresponds to a directory that has already been seen,
return true to indicate that there is a directory cycle.
- Note that this is done `lazily', which means that some of
+ Note that this is done "lazily", which means that some of
the directories in the cycle may be processed twice before
the cycle is detected. */
if (state->chdir_counter && SAME_INODE (*sb, state->dev_ino))
return true;
- /* If the number of `descending' chdir calls is a power of two,
+ /* If the number of "descending" chdir calls is a power of two,
record the dev/ino of the current directory. */
if (is_zero_or_power_of_two (++(state->chdir_counter)))
{
/* On all architectures that we know about, if the counter
- overflows then there is a directory cycle here somewhere,
- even if we haven't detected it yet. Typically this happens
- only after the counter is incremented 2**64 times, so it's a
- fairly theoretical point. */
+ overflows then there is a directory cycle here somewhere,
+ even if we haven't detected it yet. Typically this happens
+ only after the counter is incremented 2**64 times, so it's a
+ fairly theoretical point. */
if (state->chdir_counter == 0)
- return true;
+ return true;
state->dev_ino.st_dev = sb->st_dev;
state->dev_ino.st_ino = sb->st_ino;