dep: add github.com/ceph/go-ceph for rbd API

Signed-off-by: Niels de Vos <ndevos@redhat.com>

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

@@ -0,0 +1,104 @@
+// +build !luminous,!mimic
+//
+// Ceph Nautilus introduced rbd_get_parent() and deprecated rbd_get_parent_info().
+// Ceph Nautilus introduced rbd_list_children3() and deprecated rbd_list_children().
+
+package rbd
+
+// #cgo LDFLAGS: -lrbd
+// #include <rbd/librbd.h>
+// #include <errno.h>
+import "C"
+
+import (
+	"fmt"
+	"unsafe"
+)
+
+// GetParentInfo looks for the parent of the image and stores the pool, name
+// and snapshot-name in the byte-arrays that are passed as arguments.
+//
+// Implements:
+//   int rbd_get_parent(rbd_image_t image,
+//                      rbd_linked_image_spec_t *parent_image,
+//                      rbd_snap_spec_t *parent_snap)
+func (image *Image) GetParentInfo(pool, name, snapname []byte) error {
+	if err := image.validate(imageIsOpen); err != nil {
+		return err
+	}
+
+	parentImage := C.rbd_linked_image_spec_t{}
+	parentSnap := C.rbd_snap_spec_t{}
+	ret := C.rbd_get_parent(image.image, &parentImage, &parentSnap)
+	if ret != 0 {
+		return RBDError(ret)
+	}
+
+	defer C.rbd_linked_image_spec_cleanup(&parentImage)
+	defer C.rbd_snap_spec_cleanup(&parentSnap)
+
+	strlen := int(C.strlen(parentImage.pool_name))
+	if len(pool) < strlen {
+		return RBDError(C.ERANGE)
+	}
+	if copy(pool, C.GoString(parentImage.pool_name)) != strlen {
+		return RBDError(C.ERANGE)
+	}
+
+	strlen = int(C.strlen(parentImage.image_name))
+	if len(name) < strlen {
+		return RBDError(C.ERANGE)
+	}
+	if copy(name, C.GoString(parentImage.image_name)) != strlen {
+		return RBDError(C.ERANGE)
+	}
+
+	strlen = int(C.strlen(parentSnap.name))
+	if len(snapname) < strlen {
+		return RBDError(C.ERANGE)
+	}
+	if copy(snapname, C.GoString(parentSnap.name)) != strlen {
+		return RBDError(C.ERANGE)
+	}
+
+	return nil
+}
+
+// ListChildren returns arrays with the pools and names of the images that are
+// children of the given image. The index of the pools and images arrays can be
+// used to link the two items together.
+//
+// Implements:
+//   int rbd_list_children3(rbd_image_t image, rbd_linked_image_spec_t *images,
+//                          size_t *max_images);
+func (image *Image) ListChildren() (pools []string, images []string, err error) {
+	if err := image.validate(imageIsOpen); err != nil {
+		return nil, nil, err
+	}
+
+	size := C.size_t(0)
+	ret := C.rbd_list_children3(image.image, nil, &size)
+	if ret < 0 && ret != -C.ERANGE {
+		return nil, nil, RBDError(ret)
+	} else if ret > 0 {
+		return nil, nil, fmt.Errorf("rbd_list_children3() returned %d, expected 0", ret)
+	} else if ret == 0 && size == 0 {
+		return nil, nil, nil
+	}
+
+	// expected: ret == -ERANGE, size contains number of image names
+	children := make([]C.rbd_linked_image_spec_t, size)
+	ret = C.rbd_list_children3(image.image, (*C.rbd_linked_image_spec_t)(unsafe.Pointer(&children[0])), &size)
+	if ret < 0 {
+		return nil, nil, RBDError(ret)
+	}
+	defer C.rbd_linked_image_spec_list_cleanup((*C.rbd_linked_image_spec_t)(unsafe.Pointer(&children[0])), size)
+
+	pools = make([]string, size)
+	images = make([]string, size)
+	for i, child := range children {
+		pools[i] = C.GoString(child.pool_name)
+		images[i] = C.GoString(child.image_name)
+	}
+	return pools, images, nil
+}