[PATCH 1/2] unpack-trees: handle lstat failure for existing directory

When check_leading_path notices no file in the way of the new entry to
be checked out, verify_absent checks whether there is a directory
there or nothing at all.  If that lstat call fails (for example due to
ENOMEM), it assumes ENOENT, meaning a directory with untracked files
would be clobbered in that case.

Check errno after calling lstat, and for conditions other than ENOENT,
just error out.

This is a theoretical race condition.  lstat has to succeed moments
before it fails for there to be trouble.

Signed-off-by: Jonathan Nieder <redacted>
---
Does this need an o->gently check?

 unpack-trees.c |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)

diff --git a/unpack-trees.c b/unpack-trees.c
index 1ca41b1..a795db5 100644
--- a/unpack-trees.c
+++ b/unpack-trees.c

@@ -1382,7 +1382,9 @@ static int verify_absent_1(struct cache_entry *ce,
 		return check_ok_to_remove(ce->name, ce_namelen(ce),
 				ce_to_dtype(ce), ce, &st,
 				error_type, o);
-
+	if (errno != ENOENT)
+		return error("cannot stat '%s': %s", ce->name,
+				strerror(errno));
 	return 0;
 }
 

-- 
1.7.4.rc1