sha1_file: teach packed_object_info about typename

In commit 46f0344 ("sha1_file: support reading from a loose object of
unknown type", 2015-05-06), "struct object_info" gained a "typename"
field that could represent a type name from a loose object file, whether
valid or invalid, as opposed to the existing "typep" which could only
represent valid types. Some relatively complex manipulations were added
to avoid breaking packed_object_info() without modifying it, but it is
much easier to just teach packed_object_info() about the new field.
Therefore, teach packed_object_info() as described above.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

sha1_file.c

@@ -2277,9 +2277,18 @@ int packed_object_info(struct packed_git *p, off_t obj_offset,
 		*oi->disk_sizep = revidx[1].offset - obj_offset;
 	}
 
-	if (oi->typep) {
-		*oi->typep = packed_to_object_type(p, obj_offset, type, &w_curs, curpos);
-		if (*oi->typep < 0) {
+	if (oi->typep || oi->typename) {
+		enum object_type ptot;
+		ptot = packed_to_object_type(p, obj_offset, type, &w_curs,
+					     curpos);
+		if (oi->typep)
+			*oi->typep = ptot;
+		if (oi->typename) {
+			const char *tn = typename(ptot);
+			if (tn)
+				strbuf_addstr(oi->typename, tn);
+		}
+		if (ptot < 0) {
 			type = OBJ_BAD;
 			goto out;
 		}
@@ -2960,7 +2969,6 @@ int sha1_object_info_extended(const unsigned char *sha1, struct object_info *oi,
 	struct cached_object *co;
 	struct pack_entry e;
 	int rtype;
-	enum object_type real_type;
 	const unsigned char *real = lookup_replace_object_extended(sha1, flags);
 
 	co = find_cached_object(real);
@@ -2992,18 +3000,9 @@ int sha1_object_info_extended(const unsigned char *sha1, struct object_info *oi,
 			return -1;
 	}
 
-	/*
-	 * packed_object_info() does not follow the delta chain to
-	 * find out the real type, unless it is given oi->typep.
-	 */
-	if (oi->typename && !oi->typep)
-		oi->typep = &real_type;
-
 	rtype = packed_object_info(e.p, e.offset, oi);
 	if (rtype < 0) {
 		mark_bad_packed_object(e.p, real);
-		if (oi->typep == &real_type)
-			oi->typep = NULL;
 		return sha1_object_info_extended(real, oi, 0);
 	} else if (in_delta_base_cache(e.p, e.offset)) {
 		oi->whence = OI_DBCACHED;
@@ -3014,10 +3013,6 @@ int sha1_object_info_extended(const unsigned char *sha1, struct object_info *oi,
 		oi->u.packed.is_delta = (rtype == OBJ_REF_DELTA ||
 					 rtype == OBJ_OFS_DELTA);
 	}
-	if (oi->typename)
-		strbuf_addstr(oi->typename, typename(*oi->typep));
-	if (oi->typep == &real_type)
-		oi->typep = NULL;
 
 	return 0;
 }