Add rbd_get_parent_info

Signed-off-by: Ye Yin <eyniy@qq.com>

rbd/rbd.go

@@ -741,6 +741,25 @@ func (image *Image) GetSnapshot(snapname string) *Snapshot {
 	}
 }
 
+// int rbd_get_parent_info(rbd_image_t image,
+//  char *parent_pool_name, size_t ppool_namelen, char *parent_name,
+//  size_t pnamelen, char *parent_snap_name, size_t psnap_namelen)
+func (image *Image) GetParentInfo(p_pool, p_name, p_snapname []byte) error {
+	ret := C.rbd_get_parent_info(
+		image.image,
+		(*C.char)(unsafe.Pointer(&p_pool[0])),
+		(C.size_t)(len(p_pool)),
+		(*C.char)(unsafe.Pointer(&p_name[0])),
+		(C.size_t)(len(p_name)),
+		(*C.char)(unsafe.Pointer(&p_snapname[0])),
+		(C.size_t)(len(p_snapname)))
+	if ret == 0 {
+		return nil
+	} else {
+		return RBDError(int(ret))
+	}
+}
+
 // int rbd_snap_remove(rbd_image_t image, const char *snapname);
 func (snapshot *Snapshot) Remove() error {
 	var c_snapname *C.char = C.CString(snapshot.name)

rbd/rbd_test.go

@@ -1,6 +1,7 @@
 package rbd_test
 
 import (
+	"bytes"
 	"encoding/json"
 	"github.com/noahdesu/go-ceph/rados"
 	"github.com/noahdesu/go-ceph/rbd"
@@ -161,3 +162,71 @@ func TestCreateSnapshot(t *testing.T) {
 	conn.DeletePool(poolname)
 	conn.Shutdown()
 }
+
+func TestParentInfo(t *testing.T) {
+	conn, _ := rados.NewConn()
+	conn.ReadDefaultConfigFile()
+	conn.Connect()
+
+	poolname := GetUUID()
+	err := conn.MakePool(poolname)
+	assert.NoError(t, err)
+
+	ioctx, err := conn.OpenIOContext(poolname)
+	assert.NoError(t, err)
+
+	name := "parent"
+	img, err := rbd.Create(ioctx, name, 1<<22, 1)
+	assert.NoError(t, err)
+
+	err = img.Open()
+	assert.NoError(t, err)
+
+	snapshot, err := img.CreateSnapshot("mysnap")
+	assert.NoError(t, err)
+
+	err = snapshot.Protect()
+	assert.NoError(t, err)
+
+	imgNew, err := img.Clone("mysnap", ioctx, "child", 1)
+	assert.NoError(t, err)
+
+	err = imgNew.Open()
+	assert.NoError(t, err)
+	parentPool := make([]byte, 128)
+	parentName := make([]byte, 128)
+	parentSnapname := make([]byte, 128)
+
+	err = imgNew.GetParentInfo(parentPool, parentName, parentSnapname)
+	assert.NoError(t, err)
+
+	n := bytes.Index(parentName, []byte{0})
+	pName := string(parentName[:n])
+
+	n = bytes.Index(parentSnapname, []byte{0})
+	pSnapname := string(parentSnapname[:n])
+	assert.Equal(t, pName, "parent", "they should be equal")
+	assert.Equal(t, pSnapname, "mysnap", "they should be equal")
+
+	err = imgNew.Close()
+	assert.NoError(t, err)
+
+	err = imgNew.Remove()
+	assert.NoError(t, err)
+
+	err = snapshot.Unprotect()
+	assert.NoError(t, err)
+
+	err = snapshot.Remove()
+	assert.NoError(t, err)
+
+	err = img.Close()
+	assert.NoError(t, err)
+
+	err = img.Remove()
+	assert.NoError(t, err)
+
+	ioctx.Destroy()
+	conn.DeletePool(poolname)
+	conn.Shutdown()
+}