func collectFileInfo(sourceDir string) (*FileInfo, error) {
root := newRootFileInfo()
err := filepath.Walk(sourceDir, func(path string, f os.FileInfo, err error) error {
if err != nil {
return err
}
// Rebase path
relPath, err := filepath.Rel(sourceDir, path)
if err != nil {
return err
}
// As this runs on the daemon side, file paths are OS specific.
relPath = filepath.Join(string(os.PathSeparator), relPath)
// See https://github.com/golang/go/issues/9168 - bug in filepath.Join.
// Temporary workaround. If the returned path starts with two backslashes,
// trim it down to a single backslash. Only relevant on Windows.
if runtime.GOOS == "windows" {
if strings.HasPrefix(relPath, `\\`) {
relPath = relPath[1:]
}
}
if relPath == string(os.PathSeparator) {
return nil
}
parent := root.LookUp(filepath.Dir(relPath))
if parent == nil {
return fmt.Errorf("collectFileInfo: Unexpectedly no parent for %s", relPath)
}
info := &FileInfo{
name: filepath.Base(relPath),
children: make(map[string]*FileInfo),
parent: parent,
}
s, err := system.Lstat(path)
if err != nil {
return err
}
info.stat = s
info.capability, _ = system.Lgetxattr(path, "security.capability")
parent.children[info.name] = info
return nil
})
if err != nil {
return nil, err
}
return root, nil
}
func TestTarUntarWithXattr(t *testing.T) {
origin, err := ioutil.TempDir("", "docker-test-untar-origin")
if err != nil {
t.Fatal(err)
}
defer os.RemoveAll(origin)
if err := ioutil.WriteFile(path.Join(origin, "1"), []byte("hello world"), 0700); err != nil {
t.Fatal(err)
}
if err := ioutil.WriteFile(path.Join(origin, "2"), []byte("welcome!"), 0700); err != nil {
t.Fatal(err)
}
if err := ioutil.WriteFile(path.Join(origin, "3"), []byte("will be ignored"), 0700); err != nil {
t.Fatal(err)
}
if err := system.Lsetxattr(path.Join(origin, "2"), "security.capability", []byte{0x00}, 0); err != nil {
t.Fatal(err)
}
for _, c := range []Compression{
Uncompressed,
Gzip,
} {
changes, err := tarUntar(t, origin, &TarOptions{
Compression: c,
ExcludePatterns: []string{"3"},
})
if err != nil {
t.Fatalf("Error tar/untar for compression %s: %s", c.Extension(), err)
}
if len(changes) != 1 || changes[0].Path != "/3" {
t.Fatalf("Unexpected differences after tarUntar: %v", changes)
}
capability, _ := system.Lgetxattr(path.Join(origin, "2"), "security.capability")
if capability == nil && capability[0] != 0x00 {
t.Fatalf("Untar should have kept the 'security.capability' xattr.")
}
}
}
// Given a FileInfo, its path info, and a reference to the root of the tree
// being constructed, register this file with the tree.
func walkchunk(path string, fi os.FileInfo, dir string, root *FileInfo) error {
if fi == nil {
return nil
}
parent := root.LookUp(filepath.Dir(path))
if parent == nil {
return fmt.Errorf("collectFileInfoForChanges: Unexpectedly no parent for %s", path)
}
info := &FileInfo{
name: filepath.Base(path),
children: make(map[string]*FileInfo),
parent: parent,
}
cpath := filepath.Join(dir, path)
stat, err := system.FromStatT(fi.Sys().(*syscall.Stat_t))
if err != nil {
return err
}
info.stat = stat
info.capability, _ = system.Lgetxattr(cpath, "security.capability") // lgetxattr(2): fs access
parent.children[info.name] = info
return nil
}
func (ta *tarAppender) addTarFile(path, name string) error {
fi, err := os.Lstat(path)
if err != nil {
return err
}
link := ""
if fi.Mode()&os.ModeSymlink != 0 {
if link, err = os.Readlink(path); err != nil {
return err
}
}
hdr, err := tar.FileInfoHeader(fi, link)
if err != nil {
return err
}
hdr.Mode = int64(chmodTarEntry(os.FileMode(hdr.Mode)))
name, err = canonicalTarName(name, fi.IsDir())
if err != nil {
return fmt.Errorf("tar: cannot canonicalize path: %v", err)
}
hdr.Name = name
inode, err := setHeaderForSpecialDevice(hdr, ta, name, fi.Sys())
if err != nil {
return err
}
// if it's not a directory and has more than 1 link,
// it's hardlinked, so set the type flag accordingly
if !fi.IsDir() && hasHardlinks(fi) {
// a link should have a name that it links too
// and that linked name should be first in the tar archive
if oldpath, ok := ta.SeenFiles[inode]; ok {
hdr.Typeflag = tar.TypeLink
hdr.Linkname = oldpath
hdr.Size = 0 // This Must be here for the writer math to add up!
} else {
ta.SeenFiles[inode] = name
}
}
capability, _ := system.Lgetxattr(path, "security.capability")
if capability != nil {
hdr.Xattrs = make(map[string]string)
hdr.Xattrs["security.capability"] = string(capability)
}
//handle re-mapping container ID mappings back to host ID mappings before
//writing tar headers/files. We skip whiteout files because they were written
//by the kernel and already have proper ownership relative to the host
if !strings.HasPrefix(filepath.Base(hdr.Name), WhiteoutPrefix) && (ta.UIDMaps != nil || ta.GIDMaps != nil) {
uid, gid, err := getFileUIDGID(fi.Sys())
if err != nil {
return err
}
xUID, err := idtools.ToContainer(uid, ta.UIDMaps)
if err != nil {
return err
}
xGID, err := idtools.ToContainer(gid, ta.GIDMaps)
if err != nil {
return err
}
hdr.Uid = xUID
hdr.Gid = xGID
}
if err := ta.TarWriter.WriteHeader(hdr); err != nil {
return err
}
if hdr.Typeflag == tar.TypeReg {
file, err := os.Open(path)
if err != nil {
return err
}
ta.Buffer.Reset(ta.TarWriter)
defer ta.Buffer.Reset(nil)
_, err = io.Copy(ta.Buffer, file)
file.Close()
if err != nil {
return err
}
err = ta.Buffer.Flush()
if err != nil {
return err
}
}
return nil
}