ceph-csi/internal/rbd/features/features.go
Niels de Vos 3802dd2c2c rbd: add feature check to see if GroupSnapGetInfo is available
The go-ceph rbd package provides the GroupSnapGetInfo function, but it
may return ErrUnsupported when called. Returning this error after
advertising the support for VolumeGroupSnapshot seems ugly.

In order to advertise support for VolumeGroupSnapshot,
SupportsGroupSnapGetInfo() can be used, which detects the required C
function of librbd.

Signed-off-by: Niels de Vos <ndevos@ibm.com>
2024-10-10 15:45:47 +00:00

59 lines
1.6 KiB
Go

/*
Copyright 2024 The Ceph-CSI Authors.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
package features
/*
#cgo LDFLAGS: -lrbd
#include <rbd/librbd.h>
*/
import "C"
import (
"strings"
"sync"
)
var (
groupGetSnapInfoOnce sync.Once
errGroupGetSnapInfo error
groupGetSnapInfoSupported = false
)
// SupportsGroupSnapGetInfo detects if librbd has the rbd_group_snap_get_info
// function.
func SupportsGroupSnapGetInfo() (bool, error) {
groupGetSnapInfoOnce.Do(func() {
// make sure librbd.so.x is loaded, might not (yet) be the case
// if no rbd functions are called
var opts C.rbd_image_options_t
//nolint:gocritic // ignore result of rbd_image_options functions
C.rbd_image_options_create(&opts)
C.rbd_image_options_destroy(opts)
// check for rbd_group_snap_get_info() in loaded libs/symbols
errGroupGetSnapInfo = dlsym("rbd_group_snap_get_info")
if errGroupGetSnapInfo == nil {
groupGetSnapInfoSupported = true
} else if strings.Contains(errGroupGetSnapInfo.Error(), "undefined symbol") {
errGroupGetSnapInfo = nil
}
})
return groupGetSnapInfoSupported, errGroupGetSnapInfo
}