dotcloud/docker

package zfs // import "github.com/docker/docker/daemon/graphdriver/zfs"

import (
    "strings"

    "github.com/containerd/log"
    "github.com/docker/docker/daemon/graphdriver"
    "golang.org/x/sys/unix"
)

func checkRootdirFs(rootdir string) error {
    var buf unix.Statfs_t
    if err := unix.Statfs(rootdir, &buf); err != nil {
        return err
    }

    // on FreeBSD buf.Fstypename contains ['z', 'f', 's', 0 ... ]
    if (buf.Fstypename[0] != 122) || (buf.Fstypename[1] != 102) || (buf.Fstypename[2] != 115) || (buf.Fstypename[3] != 0) {
        log.G(ctx).WithField("storage-driver", "zfs").Debugf("no zfs dataset found for rootdir '%s'", rootdir)
        return graphdriver.ErrPrerequisites
    }

    return nil
}

const maxlen = 12

func getMountpoint(id string) string {
    id, suffix, _ := strings.Cut(id, "-")
    id = id[:maxlen]
    if suffix != "" {
        // preserve filesystem suffix.
        id += "-" + suffix
    }
    return id
}