// // 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 ( "unsafe" "github.com/ceph/go-ceph/internal/retry" ) // 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 } // ImageSpec represents the image information. type ImageSpec struct { ImageName string PoolName string } // SnapSpec represents the snapshot infomation. type SnapSpec struct { ID uint64 SnapName string } // ParentInfo represents the parent image and the parent snapshot information. type ParentInfo struct { Image ImageSpec Snap SnapSpec } // GetParent looks for the parent of the image and returns the parent image // information which includes the image name, the pool name and // the snapshot information. // // 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) GetParent() (*ParentInfo, error) { if err := image.validate(imageIsOpen); err != nil { return nil, 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 nil, getError(ret) } defer C.rbd_linked_image_spec_cleanup(&parentImage) defer C.rbd_snap_spec_cleanup(&parentSnap) imageSpec := ImageSpec{ ImageName: C.GoString(parentImage.image_name), PoolName: C.GoString(parentImage.pool_name), } snapSpec := SnapSpec{ ID: uint64(parentSnap.id), SnapName: C.GoString(parentSnap.name), } return &ParentInfo{ Image: imageSpec, Snap: snapSpec, }, 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 } var ( csize C.size_t children []C.rbd_linked_image_spec_t ) retry.WithSizes(16, 4096, func(size int) retry.Hint { csize = C.size_t(size) children = make([]C.rbd_linked_image_spec_t, csize) ret := C.rbd_list_children3( image.image, (*C.rbd_linked_image_spec_t)(unsafe.Pointer(&children[0])), &csize) err = getErrorIfNegative(ret) return retry.Size(int(csize)).If(err == errRange) }) if err != nil { return nil, nil, err } defer C.rbd_linked_image_spec_list_cleanup((*C.rbd_linked_image_spec_t)(unsafe.Pointer(&children[0])), csize) pools = make([]string, csize) images = make([]string, csize) for i, child := range children[:csize] { pools[i] = C.GoString(child.pool_name) images[i] = C.GoString(child.image_name) } return pools, images, nil } // SetSnapByID updates the rbd image (not the Snapshot) such that the snapshot // is the source of readable data. // // Implements: // // int rbd_snap_set_by_id(rbd_image_t image, uint64_t snap_id); func (image *Image) SetSnapByID(snapID uint64) error { if err := image.validate(imageIsOpen); err != nil { return err } ret := C.rbd_snap_set_by_id(image.image, C.uint64_t(snapID)) return getError(ret) }