[PATCH]

f2eba66 (Enable HEAD@{...} and make it independent from the current
branch, 2007-02-03) introduced dwim_log() to handle <refname>@{...}
syntax, and as part of its processing, it checks if the ref exists by
calling refsolve_ref().  It should call it as a reader to make sure the
call returns NULL for a nonexistent ref (not as a potential writer in
which case it does not return NULL).

Signed-off-by: Junio C Hamano <redacted>
---

 * I found this purely by accident.  "echo >.git/logs/refs/heads/HEAD"
   would make your "git rev-parse HEAD@{1}" complain about a refname
   'HEAD' being ambiguous without this patch.

 sha1_name.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/sha1_name.c b/sha1_name.c
index b0b2167..4fb77f8 100644
--- a/sha1_name.c
+++ b/sha1_name.c

@@ -273,7 +273,7 @@ int dwim_log(const char *str, int len, unsigned char *sha1, char **log)
 		const char *ref, *it;
 
 		strcpy(path, mkpath(*p, len, str));
-		ref = resolve_ref(path, hash, 0, NULL);
+		ref = resolve_ref(path, hash, 1, NULL);
 		if (!ref)
 			continue;
 		if (!stat(git_path("logs/%s", path), &st) &&