[PATCH] lock_ref_sha1_basic does not remove empty directories on BSD

lock_ref_sha1_basic relies on errno beeing set to EISDIR by the
call to read() in resolve_ref() to detect directories.  But calling
read() on a directory under NetBSD returns EPERM, and even succeeds
for local filesystems on FreeBSD.

Signed-off-by: Dennis Stosberg <redacted>
---
 refs.c |    6 ++++++
 1 files changed, 6 insertions(+), 0 deletions(-)

diff --git a/refs.c b/refs.c
index aa4c4e0..305c1a9 100644
--- a/refs.c
+++ b/refs.c

@@ -234,6 +234,12 @@ const char *resolve_ref(const char *ref,
 			}
 		}
 
+		/* Is it a directory? */
+		if (S_ISDIR(st.st_mode)) {
+			errno = EISDIR;
+			return NULL;
+		}
+
 		/*
 		 * Anything else, just open it and try to use it as
 		 * a ref

-- 
1.4.2