podman/vendor/github.com/fsouza/go-dockerclient/internal/archive/whiteouts.go

28 lines
1.2 KiB
Go

// Copyright 2014 Docker authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the DOCKER-LICENSE file.
package archive
// Whiteouts are files with a special meaning for the layered filesystem.
// Docker uses AUFS whiteout files inside exported archives. In other
// filesystems these files are generated/handled on tar creation/extraction.
// WhiteoutPrefix prefix means file is a whiteout. If this is followed by a
// filename this means that file has been removed from the base layer.
const WhiteoutPrefix = ".wh."
// WhiteoutMetaPrefix prefix means whiteout has a special meaning and is not
// for removing an actual file. Normally these files are excluded from exported
// archives.
const WhiteoutMetaPrefix = WhiteoutPrefix + WhiteoutPrefix
// WhiteoutLinkDir is a directory AUFS uses for storing hardlink links to other
// layers. Normally these should not go into exported archives and all changed
// hardlinks should be copied to the top layer.
const WhiteoutLinkDir = WhiteoutMetaPrefix + "plnk"
// WhiteoutOpaqueDir file means directory has been made opaque - meaning
// readdir calls to this directory do not follow to lower layers.
const WhiteoutOpaqueDir = WhiteoutMetaPrefix + ".opq"