resolve_ref(): expose REF_ISBROKEN flag

Instead of keeping this as an internal API, let the callers find
out the reason why resolve_ref() returned NULL is not because there
was no such file in $GIT_DIR but because a file was corrupt.

Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 3 insertions, 2 deletions

diff --git a/refs.h b/refs.h
index d5ac133336..e4578856d7 100644
--- a/refs.h
+++ b/refs.h
@@ -10,8 +10,9 @@ struct ref_lock {
 	int force_write;
 };
 
-#define REF_ISSYMREF 01
-#define REF_ISPACKED 02
+#define REF_ISSYMREF 0x01
+#define REF_ISPACKED 0x02
+#define REF_ISBROKEN 0x04
 
 /*
  * Calls the specified function for each ref file until it returns nonzero,