disk: implement VolumeContainer interface for PartitionTable

Co-Authored-By: Christian Kellner <christian@kellner.me>

internal/disk/disk_test.go

@@ -66,9 +66,9 @@ func TestDisk_DynamicallyResizePartitionTable(t *testing.T) {
 	// math/rand is good enough in this case
 	/* #nosec G404 */
 	rng := rand.New(rand.NewSource(0))
-	pt, err := CreatePartitionTable(mountpoints, 1024, &pt, rng)
+	newpt, err := NewPartitionTable(&pt, mountpoints, 1024, rng)
 	assert.NoError(t, err)
-	assert.GreaterOrEqual(t, pt.SectorsToBytes(pt.Size), expectedSize)
+	assert.GreaterOrEqual(t, newpt.Size, expectedSize)
 }
 
 // common partition table that use used by tests

internal/disk/partition_table.go

@@ -283,6 +283,39 @@ func (pt *PartitionTable) EnsureSize(s uint64) bool {
 	return false
 }
 
+func (pt *PartitionTable) CreateVolume(mountpoint string, size uint64) (Entity, error) {
+	filesystem := Filesystem{
+		Type:         "xfs",
+		Mountpoint:   mountpoint,
+		FSTabOptions: "defaults",
+		FSTabFreq:    0,
+		FSTabPassNo:  0,
+	}
+
+	partition := Partition{
+		Size:    size,
+		Payload: &filesystem,
+	}
+
+	n := len(pt.Partitions)
+	var maxNo int
+
+	if pt.Type == "gpt" {
+		partition.Type = FilesystemDataGUID
+		maxNo = 128
+	} else {
+		maxNo = 4
+	}
+
+	if n == maxNo {
+		return nil, fmt.Errorf("maximum number of partitions reached (%d)", maxNo)
+	}
+
+	pt.Partitions = append(pt.Partitions, partition)
+
+	return &pt.Partitions[len(pt.Partitions)-1], nil
+}
+
 type EntityCallback func(e Entity, path []Entity) error
 
 func forEachEntity(e Entity, path []Entity, cb EntityCallback) error {