Extend quorum based listing for prefixes (#5749)

Previous PR 2afd196c83 fixed
the issue of quorum based listing for regular objects, this
PR continues on this idea by extending this support to
object directory prefixes as well.

Fixes #5733

cmd/xl-sets.go

@@ -725,17 +725,13 @@ func (s *xlSets) ListObjects(ctx context.Context, bucket, prefix, marker, delimi
 			return result, toObjectErr(walkResult.err, bucket, prefix)
 		}
 
-		entry := walkResult.entry
 		var objInfo ObjectInfo
-		if hasSuffix(entry, slashSeparator) {
-			// Object name needs to be full path.
-			objInfo.Bucket = bucket
-			objInfo.Name = entry
-			objInfo.IsDir = true
-		} else {
-			// Set the Mode to a "regular" file.
 		var err error
-			objInfo, err = s.getHashedSet(entry).getObjectInfo(bucket, entry)
+		if hasSuffix(walkResult.entry, slashSeparator) {
+			objInfo, err = s.getHashedSet(walkResult.entry).getObjectInfoDir(bucket, walkResult.entry)
+		} else {
+			objInfo, err = s.getHashedSet(walkResult.entry).getObjectInfo(bucket, walkResult.entry)
+		}
 		if err != nil {
 			// Ignore errFileNotFound as the object might have got
 			// deleted in the interim period of listing and getObjectInfo(),
@@ -746,7 +742,6 @@ func (s *xlSets) ListObjects(ctx context.Context, bucket, prefix, marker, delimi
 			}
 			return result, toObjectErr(err, bucket, prefix)
 		}
-		}
 		nextMarker = objInfo.Name
 		objInfos = append(objInfos, objInfo)
 		i++
@@ -1270,16 +1265,13 @@ func (s *xlSets) listObjectsHeal(bucket, prefix, marker, delimiter string, maxKe
 		if walkResult.err != nil {
 			return loi, toObjectErr(walkResult.err, bucket, prefix)
 		}
-		entry := walkResult.entry
 		var objInfo ObjectInfo
-		if hasSuffix(entry, slashSeparator) {
-			// Object name needs to be full path.
-			objInfo.Bucket = bucket
-			objInfo.Name = entry
-			objInfo.IsDir = true
-		} else {
 		var err error
-			objInfo, err = s.getHashedSet(entry).getObjectInfo(bucket, entry)
+		if hasSuffix(walkResult.entry, slashSeparator) {
+			objInfo, err = s.getHashedSet(walkResult.entry).getObjectInfoDir(bucket, walkResult.entry)
+		} else {
+			objInfo, err = s.getHashedSet(walkResult.entry).getObjectInfo(bucket, walkResult.entry)
+		}
 		if err != nil {
 			// Ignore errFileNotFound
 			if errors.Cause(err) == errFileNotFound {
@@ -1287,7 +1279,6 @@ func (s *xlSets) listObjectsHeal(bucket, prefix, marker, delimiter string, maxKe
 			}
 			return loi, toObjectErr(err, bucket, prefix)
 		}
-		}
 		nextMarker = objInfo.Name
 		objInfos = append(objInfos, objInfo)
 		i++