[PATCH] fts: avoid false-positive cycle-detection

[Jim Meyering]

I'm considering a rewrite of rm that uses fts.c,
and see that the resulting rm fails coreutils' rm/cycle test
because it incorrectly reports a cycle for that unusual case.

The following patch fixes fts so that it properly reinitializes one of
its cycle-detection data structure for each new command line argument.

I might save a little by merely clearing the hash table
and reusing it, rather than freeing it altogether, but don't
think that would be worth the added code.

I have not yet been able to cause trouble with chmod, chown, chcon,
or du, but haven't tried very hard, either.

>From a90d85f9e7ca8329d05bb7dd02cf807b9086b71e Mon Sep 17 00:00:00 2001
From: Jim Meyering <meyer...@redhat.com>
Date: Sun, 19 Jul 2009 22:33:09 +0200
Subject: [PATCH] fts: avoid false-positive cycle-detection

* lib/fts.c (fts_read): Reinitialize cycle-detection data structures
for each new command line argument.
---
 ChangeLog |    6 ++++++
 lib/fts.c |    2 ++
 2 files changed, 8 insertions(+), 0 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 56a6bda..9c78852 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2009-07-19  Jim Meyering  <meyer...@redhat.com>
+
+       fts: avoid false-positive cycle-detection
+       * lib/fts.c (fts_read): Reinitialize cycle-detection data structures
+       for each new command line argument.
+
 2009-07-19  Bruno Haible  <br...@clisp.org>

        Fix build error on mingw with the modules sys_select and unistd.
diff --git a/lib/fts.c b/lib/fts.c
index 0cbb9fb..bbcd1ff 100644
--- a/lib/fts.c
+++ b/lib/fts.c
@@ -932,7 +932,9 @@ next:       tmp = p;
                                SET(FTS_STOP);
                                return (NULL);
                        }
+                       free_dir(sp);
                        fts_load(sp, p);
+                       setup_dir(sp);
                        goto check_for_dir;
                }

--
1.6.4.rc1.169.gd0406