[PATCH 3/3] rev_is_head(): use skip_prefix()

[Michael Haggerty <mhagger@alum.mit.edu>]

Change the logic a little bit so that we can use skip_prefix() instead
of doing pointer arithmetic with hardcoded numbers.

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
---
 builtin/show-branch.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/builtin/show-branch.c b/builtin/show-branch.c
index f2c3b19..aee7fe5 100644
--- a/builtin/show-branch.c
+++ b/builtin/show-branch.c
@@ -475,14 +475,15 @@ static void snarf_refs(int head, int remotes)
 static int rev_is_head(const char *head, int headlen, const char *name,
 		       unsigned char *head_sha1, unsigned char *sha1)
 {
+	const char *short_name;
+
 	if ((!head[0]) ||
 	    (head_sha1 && sha1 && hashcmp(head_sha1, sha1)))
 		return 0;
 	head = skip_prefix_if_present(head, "refs/heads/");
-	if (starts_with(name, "refs/heads/"))
-		name += 11;
-	else if (starts_with(name, "heads/"))
-		name += 6;
+	if ((short_name = skip_prefix(name, "refs/heads/")) ||
+	    (short_name = skip_prefix(name, "heads/")))
+		return !strcmp(head, short_name);
 	return !strcmp(head, name);
 }
 
-- 
1.8.5.3