[PATCH] do_for_each_ref: perform the same sanity check for leftovers.

[Junio C Hamano <junkio@cox.net>]

An earlier commit b37a562a added a check to see if the ref
points at a valid object (as a part of 'negative ref' support
which we currently do not use), but did so only while iterating
over both packed and loose refs, and forgot to apply the same
check while iterating over the remaining ones.

We might want to replace the "if null then omit it" check with
"eh --- what business does a 0{40} value have here?" complaint
later since we currently do not use negative refs, but that is
a separate issue.

Signed-off-by: Junio C Hamano <junkio@cox.net>
---

 * "pickaxe -L'/^static int do_for_each_ref/,+40' refs.c" turns
   out to be a very handy way to find out why a line I am
   interested in is in that shape.

   But it might be even better if it allowed us to say
   '-L/^static int do_for_each_ref/+20,+20'.

diff --git a/refs.c b/refs.c
index f003a0b..6abd12f 100644
--- a/refs.c
+++ b/refs.c
@@ -322,6 +322,20 @@ int read_ref(const char *ref, unsigned c
 	return -1;
 }
 
+static inline int do_one_ref(const char *base, each_ref_fn fn, int trim,
+			     void *cb_data, struct ref_list *entry)
+{
+	if (strncmp(base, entry->name, trim))
+		return 0;
+	if (is_null_sha1(entry->sha1))
+		return 0;
+	if (!has_sha1_file(entry->sha1)) {
+		error("%s does not point to a valid object!", entry->name);
+		return 0;
+	}
+	return fn(entry->name + trim, entry->sha1, entry->flag, cb_data);
+}
+
 static int do_for_each_ref(const char *base, each_ref_fn fn, int trim,
 			   void *cb_data)
 {
@@ -343,29 +357,15 @@ static int do_for_each_ref(const char *b
 			entry = packed;
 			packed = packed->next;
 		}
-		if (strncmp(base, entry->name, trim))
-			continue;
-		if (is_null_sha1(entry->sha1))
-			continue;
-		if (!has_sha1_file(entry->sha1)) {
-			error("%s does not point to a valid object!", entry->name);
-			continue;
-		}
-		retval = fn(entry->name + trim, entry->sha1,
-			    entry->flag, cb_data);
+		retval = do_one_ref(base, fn, trim, cb_data, entry);
 		if (retval)
 			return retval;
 	}
 
-	packed = packed ? packed : loose;
-	while (packed) {
-		if (!strncmp(base, packed->name, trim)) {
-			retval = fn(packed->name + trim, packed->sha1,
-				    packed->flag, cb_data);
-			if (retval)
-				return retval;
-		}
-		packed = packed->next;
+	for (packed = packed ? packed : loose; packed; packed = packed->next) {
+		retval = do_one_ref(base, fn, trim, cb_data, packed);
+		if (retval)
+			return retval;
 	}
 	return 0;
 }