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/rados/snapshot.go

@@ -0,0 +1,189 @@
+package rados
+
+// #cgo LDFLAGS: -lrados
+// #include <stdlib.h>
+// #include <rados/librados.h>
+import "C"
+
+import (
+	"time"
+	"unsafe"
+
+	"github.com/ceph/go-ceph/internal/retry"
+)
+
+// CreateSnap creates a pool-wide snapshot.
+//
+// Implements:
+// int rados_ioctx_snap_create(rados_ioctx_t io, const char *snapname)
+func (ioctx *IOContext) CreateSnap(snapName string) error {
+	if err := ioctx.validate(); err != nil {
+		return err
+	}
+
+	cSnapName := C.CString(snapName)
+	defer C.free(unsafe.Pointer(cSnapName))
+
+	ret := C.rados_ioctx_snap_create(ioctx.ioctx, cSnapName)
+	return getError(ret)
+}
+
+// RemoveSnap deletes the pool snapshot.
+//
+// Implements:
+//  int rados_ioctx_snap_remove(rados_ioctx_t io, const char *snapname)
+func (ioctx *IOContext) RemoveSnap(snapName string) error {
+	if err := ioctx.validate(); err != nil {
+		return err
+	}
+
+	cSnapName := C.CString(snapName)
+	defer C.free(unsafe.Pointer(cSnapName))
+
+	ret := C.rados_ioctx_snap_remove(ioctx.ioctx, cSnapName)
+	return getError(ret)
+}
+
+// SnapID represents the ID of a rados snapshot.
+type SnapID C.rados_snap_t
+
+// LookupSnap returns the ID of a pool snapshot.
+//
+// Implements:
+//  int rados_ioctx_snap_lookup(rados_ioctx_t io, const char *name, rados_snap_t *id)
+func (ioctx *IOContext) LookupSnap(snapName string) (SnapID, error) {
+	var snapID SnapID
+
+	if err := ioctx.validate(); err != nil {
+		return snapID, err
+	}
+
+	cSnapName := C.CString(snapName)
+	defer C.free(unsafe.Pointer(cSnapName))
+
+	ret := C.rados_ioctx_snap_lookup(
+		ioctx.ioctx,
+		cSnapName,
+		(*C.rados_snap_t)(&snapID))
+	return snapID, getError(ret)
+}
+
+// GetSnapName returns the name of a pool snapshot with the given snapshot ID.
+//
+// Implements:
+//  int rados_ioctx_snap_get_name(rados_ioctx_t io, rados_snap_t id, char *name, int maxlen)
+func (ioctx *IOContext) GetSnapName(snapID SnapID) (string, error) {
+	if err := ioctx.validate(); err != nil {
+		return "", err
+	}
+
+	var (
+		buf []byte
+		err error
+	)
+	// range from 1k to 64KiB
+	retry.WithSizes(1024, 1<<16, func(len int) retry.Hint {
+		cLen := C.int(len)
+		buf = make([]byte, cLen)
+		ret := C.rados_ioctx_snap_get_name(
+			ioctx.ioctx,
+			(C.rados_snap_t)(snapID),
+			(*C.char)(unsafe.Pointer(&buf[0])),
+			cLen)
+		err = getError(ret)
+		return retry.Size(int(cLen)).If(err == errRange)
+	})
+
+	if err != nil {
+		return "", err
+	}
+	return C.GoString((*C.char)(unsafe.Pointer(&buf[0]))), nil
+}
+
+// GetSnapStamp returns the time of the pool snapshot creation.
+//
+// Implements:
+//  int rados_ioctx_snap_get_stamp(rados_ioctx_t io, rados_snap_t id, time_t *t)
+func (ioctx *IOContext) GetSnapStamp(snapID SnapID) (time.Time, error) {
+	var cTime C.time_t
+
+	if err := ioctx.validate(); err != nil {
+		return time.Unix(int64(cTime), 0), err
+	}
+
+	ret := C.rados_ioctx_snap_get_stamp(
+		ioctx.ioctx,
+		(C.rados_snap_t)(snapID),
+		&cTime)
+	return time.Unix(int64(cTime), 0), getError(ret)
+}
+
+// ListSnaps returns a slice containing the SnapIDs of existing pool snapshots.
+//
+// Implements:
+//  int rados_ioctx_snap_list(rados_ioctx_t io, rados_snap_t *snaps, int maxlen)
+func (ioctx *IOContext) ListSnaps() ([]SnapID, error) {
+	if err := ioctx.validate(); err != nil {
+		return nil, err
+	}
+
+	var (
+		snapList []SnapID
+		cLen     C.int
+		err      error
+		ret      C.int
+	)
+	retry.WithSizes(100, 1000, func(maxlen int) retry.Hint {
+		cLen = C.int(maxlen)
+		snapList = make([]SnapID, cLen)
+		ret = C.rados_ioctx_snap_list(
+			ioctx.ioctx,
+			(*C.rados_snap_t)(unsafe.Pointer(&snapList[0])),
+			cLen)
+		err = getErrorIfNegative(ret)
+		return retry.Size(int(cLen)).If(err == errRange)
+	})
+
+	if err != nil {
+		return nil, err
+	}
+	return snapList[:ret], nil
+}
+
+// RollbackSnap rollbacks the object with key oID to the pool snapshot.
+// The contents of the object will be the same as when the snapshot was taken.
+//
+// Implements:
+//  int rados_ioctx_snap_rollback(rados_ioctx_t io, const char *oid, const char *snapname);
+func (ioctx *IOContext) RollbackSnap(oid, snapName string) error {
+	if err := ioctx.validate(); err != nil {
+		return err
+	}
+
+	coid := C.CString(oid)
+	defer C.free(unsafe.Pointer(coid))
+	cSnapName := C.CString(snapName)
+	defer C.free(unsafe.Pointer(cSnapName))
+
+	ret := C.rados_ioctx_snap_rollback(ioctx.ioctx, coid, cSnapName)
+	return getError(ret)
+}
+
+// SnapHead is the representation of LIBRADOS_SNAP_HEAD from librados.
+// SnapHead can be used to reset the IOContext to stop reading from a snapshot.
+const SnapHead = SnapID(C.LIBRADOS_SNAP_HEAD)
+
+// SetReadSnap sets the snapshot from which reads are performed.
+// Subsequent reads will return data as it was at the time of that snapshot.
+// Pass SnapHead for no snapshot (i.e. normal operation).
+//
+// Implements:
+//  void rados_ioctx_snap_set_read(rados_ioctx_t io, rados_snap_t snap);
+func (ioctx *IOContext) SetReadSnap(snapID SnapID) error {
+	if err := ioctx.validate(); err != nil {
+		return err
+	}
+
+	C.rados_ioctx_snap_set_read(ioctx.ioctx, (C.rados_snap_t)(snapID))
+	return nil
+}