dotcloud/docker

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

const (
    // ErrNotSupported returned when driver is not supported.
    ErrNotSupported NotSupportedError = "driver not supported"
    // ErrPrerequisites returned when driver does not meet prerequisites.
    ErrPrerequisites NotSupportedError = "prerequisites for driver not satisfied (wrong filesystem?)"
    // ErrIncompatibleFS returned when file system is not supported.
    ErrIncompatibleFS NotSupportedError = "backing file system is unsupported for this graph driver"
)

// ErrUnSupported signals that the graph-driver is not supported on the current configuration
type ErrUnSupported interface {
    NotSupported()
}

// NotSupportedError signals that the graph-driver is not supported on the current configuration
type NotSupportedError string

func (e NotSupportedError) Error() string {
    return string(e)
}

// NotSupported signals that a graph-driver is not supported.
func (e NotSupportedError) NotSupported() {}

// IsDriverNotSupported returns true if the error initializing
// the graph driver is a non-supported error.
func IsDriverNotSupported(err error) bool {
    switch err.(type) {
    case ErrUnSupported:
        return true
    default:
        return false
    }
}