package dump import ( "archive/tar" "context" "io" "os" "path" "path/filepath" "strings" "github.com/restic/restic/internal/errors" "github.com/restic/restic/internal/restic" "github.com/restic/restic/internal/walker" ) // WriteTar will write the contents of the given tree, encoded as a tar to the given destination. // It will loop over all nodes in the tree and dump them recursively. func WriteTar(ctx context.Context, repo restic.Repository, tree *restic.Tree, rootPath string, dst io.Writer) error { tw := tar.NewWriter(dst) for _, rootNode := range tree.Nodes { rootNode.Path = rootPath err := tarTree(ctx, repo, rootNode, rootPath, tw) if err != nil { _ = tw.Close() return err } } return tw.Close() } func tarTree(ctx context.Context, repo restic.Repository, rootNode *restic.Node, rootPath string, tw *tar.Writer) error { rootNode.Path = path.Join(rootNode.Path, rootNode.Name) rootPath = rootNode.Path if err := tarNode(ctx, tw, rootNode, repo); err != nil { return err } // If this is no directory we are finished if !IsDir(rootNode) { return nil } err := walker.Walk(ctx, repo, *rootNode.Subtree, nil, func(_ restic.ID, nodepath string, node *restic.Node, err error) (bool, error) { if err != nil { return false, err } if node == nil { return false, nil } node.Path = path.Join(rootPath, nodepath) if IsFile(node) || IsLink(node) || IsDir(node) { err := tarNode(ctx, tw, node, repo) if err != nil { return false, err } } return false, nil }) return err } // copied from archive/tar.FileInfoHeader const ( // Mode constants from the USTAR spec: // See http://pubs.opengroup.org/onlinepubs/9699919799/utilities/pax.html#tag_20_92_13_06 c_ISUID = 04000 // Set uid c_ISGID = 02000 // Set gid c_ISVTX = 01000 // Save text (sticky bit) ) func tarNode(ctx context.Context, tw *tar.Writer, node *restic.Node, repo restic.Repository) error { relPath, err := filepath.Rel("/", node.Path) if err != nil { return err } header := &tar.Header{ Name: filepath.ToSlash(relPath), Size: int64(node.Size), Mode: int64(node.Mode.Perm()), // c_IS* constants are added later Uid: int(node.UID), Gid: int(node.GID), Uname: node.User, Gname: node.Group, ModTime: node.ModTime, AccessTime: node.AccessTime, ChangeTime: node.ChangeTime, PAXRecords: parseXattrs(node.ExtendedAttributes), } // adapted from archive/tar.FileInfoHeader if node.Mode&os.ModeSetuid != 0 { header.Mode |= c_ISUID } if node.Mode&os.ModeSetgid != 0 { header.Mode |= c_ISGID } if node.Mode&os.ModeSticky != 0 { header.Mode |= c_ISVTX } if IsFile(node) { header.Typeflag = tar.TypeReg } if IsLink(node) { header.Typeflag = tar.TypeSymlink header.Linkname = node.LinkTarget } if IsDir(node) { header.Typeflag = tar.TypeDir header.Name += "/" } err = tw.WriteHeader(header) if err != nil { return errors.Wrap(err, "TarHeader ") } return GetNodeData(ctx, tw, repo, node) } func parseXattrs(xattrs []restic.ExtendedAttribute) map[string]string { tmpMap := make(map[string]string) for _, attr := range xattrs { attrString := string(attr.Value) if strings.HasPrefix(attr.Name, "system.posix_acl_") { na := acl{} na.decode(attr.Value) if na.String() != "" { if strings.Contains(attr.Name, "system.posix_acl_access") { tmpMap["SCHILY.acl.access"] = na.String() } else if strings.Contains(attr.Name, "system.posix_acl_default") { tmpMap["SCHILY.acl.default"] = na.String() } } } else { tmpMap["SCHILY.xattr."+attr.Name] = attrString } } return tmpMap } // GetNodeData will write the contents of the node to the given output func GetNodeData(ctx context.Context, output io.Writer, repo restic.Repository, node *restic.Node) error { var ( buf []byte err error ) for _, id := range node.Content { buf, err = repo.LoadBlob(ctx, restic.DataBlob, id, buf) if err != nil { return err } _, err = output.Write(buf) if err != nil { return errors.Wrap(err, "Write") } } return nil } // IsDir checks if the given node is a directory func IsDir(node *restic.Node) bool { return node.Type == "dir" } // IsLink checks if the given node as a link func IsLink(node *restic.Node) bool { return node.Type == "symlink" } // IsFile checks if the given node is a file func IsFile(node *restic.Node) bool { return node.Type == "file" }