rebase: update go-ceph to v0.5.0

as go-ceph is 0.5.0 is released updating
the dependency to latest release.
more info about release at
https://github.com/ceph/go-ceph/releases/tag/v0.5.0

Signed-off-by: Madhu Rajanna <madhupr007@gmail.com>

vendor/github.com/ceph/go-ceph/rbd/snapshot_namespace.go

@@ -0,0 +1,80 @@
+// +build !luminous
+//
+// Ceph Mimic introduced rbd_snap_get_namespace_type().
+
+package rbd
+
+// #cgo LDFLAGS: -lrbd
+// #include <rbd/librbd.h>
+import "C"
+
+import (
+	"unsafe"
+
+	"github.com/ceph/go-ceph/internal/retry"
+)
+
+// SnapNamespaceType indicates the namespace to which the snapshot belongs to.
+type SnapNamespaceType C.rbd_snap_namespace_type_t
+
+const (
+	// SnapNamespaceTypeUser indicates that the snapshot belongs to user namespace.
+	SnapNamespaceTypeUser = SnapNamespaceType(C.RBD_SNAP_NAMESPACE_TYPE_USER)
+
+	// SnapNamespaceTypeGroup indicates that the snapshot belongs to group namespace.
+	// Such snapshots will have associated group information.
+	SnapNamespaceTypeGroup = SnapNamespaceType(C.RBD_SNAP_NAMESPACE_TYPE_GROUP)
+
+	// SnapNamespaceTypeTrash indicates that the snapshot belongs to trash namespace.
+	SnapNamespaceTypeTrash = SnapNamespaceType(C.RBD_SNAP_NAMESPACE_TYPE_TRASH)
+)
+
+// GetSnapNamespaceType gets the type of namespace to which the snapshot belongs to,
+// returns error on failure.
+//
+// Implements:
+//  int rbd_snap_get_namespace_type(rbd_image_t image, uint64_t snap_id, rbd_snap_namespace_type_t *namespace_type)
+func (image *Image) GetSnapNamespaceType(snapID uint64) (SnapNamespaceType, error) {
+	var nsType SnapNamespaceType
+
+	if err := image.validate(imageIsOpen); err != nil {
+		return nsType, err
+	}
+
+	ret := C.rbd_snap_get_namespace_type(image.image,
+		C.uint64_t(snapID),
+		(*C.rbd_snap_namespace_type_t)(&nsType))
+	return nsType, getError(ret)
+}
+
+// GetSnapTrashNamespace returns the original name of the snapshot which was
+// moved to the Trash. The caller should make sure that the snapshot ID passed in this
+// function belongs to a snapshot already in the Trash.
+//
+// Implements:
+//  int rbd_snap_get_trash_namespace(rbd_image_t image, uint64_t snap_id, char *original_name, size_t max_length)
+func (image *Image) GetSnapTrashNamespace(snapID uint64) (string, error) {
+	if err := image.validate(imageIsOpen); err != nil {
+		return "", err
+	}
+
+	var (
+		buf []byte
+		err error
+	)
+	retry.WithSizes(4096, 262144, func(length int) retry.Hint {
+		cLength := C.size_t(length)
+		buf = make([]byte, cLength)
+		ret := C.rbd_snap_get_trash_namespace(image.image,
+			C.uint64_t(snapID),
+			(*C.char)(unsafe.Pointer(&buf[0])),
+			cLength)
+		err = getError(ret)
+		return retry.Size(int(cLength)).If(err == errRange)
+	})
+
+	if err != nil {
+		return "", err
+	}
+	return C.GoString((*C.char)(unsafe.Pointer(&buf[0]))), nil
+}