vendor/github.com/containerd/containerd/fs/hardlink.go

package fs

import "os"

// GetLinkInfo returns an identifier representing the node a hardlink is pointing
// to. If the file is not hard linked then 0 will be returned.
func GetLinkInfo(fi os.FileInfo) (uint64, bool) {
	return getLinkInfo(fi)
}

// getLinkSource returns a path for the given name and
// file info to its link source in the provided inode
// map. If the given file name is not in the map and
// has other links, it is added to the inode map
// to be a source for other link locations.
func getLinkSource(name string, fi os.FileInfo, inodes map[uint64]string) (string, error) {
	inode, isHardlink := getLinkInfo(fi)
	if !isHardlink {
		return "", nil
	}

	path, ok := inodes[inode]
	if !ok {
		inodes[inode] = name
	}
	return path, nil
}