moby--moby/pkg/longpath/longpath.go

// longpath introduces some constants and helper functions for handling long paths
// in Windows, which are expected to be prepended with `\\?\` and followed by either
// a drive letter, a UNC server\share, or a volume identifier.

package longpath

import (
	"strings"
)

// Prefix is the longpath prefix for Windows file paths.
const Prefix = `\\?\`

// AddPrefix will add the Windows long path prefix to the path provided if
// it does not already have it.
func AddPrefix(path string) string {
	if !strings.HasPrefix(path, Prefix) {
		path = Prefix + path
	}
	return path
}