dump: Split tar and walk logic

This commit is contained in:
DRON-666 2020-11-10 01:22:27 +03:00
parent 22260d130d
commit 0256f95994
3 changed files with 127 additions and 95 deletions

View file

@ -65,8 +65,7 @@ func splitPath(p string) []string {
return append(s, f)
}
func printFromTree(ctx context.Context, tree *restic.Tree, repo restic.Repository, prefix string, pathComponents []string) error {
func printFromTree(ctx context.Context, tree *restic.Tree, repo restic.Repository, prefix string, pathComponents []string, writeDump dump.WriteDump) error {
if tree == nil {
return fmt.Errorf("called with a nil tree")
}
@ -81,10 +80,10 @@ func printFromTree(ctx context.Context, tree *restic.Tree, repo restic.Repositor
// If we print / we need to assume that there are multiple nodes at that
// level in the tree.
if pathComponents[0] == "" {
if err := checkStdoutTar(); err != nil {
if err := checkStdoutArchive(); err != nil {
return err
}
return dump.WriteTar(ctx, repo, tree, "/", os.Stdout)
return writeDump(ctx, repo, tree, "/", os.Stdout)
}
item := filepath.Join(prefix, pathComponents[0])
@ -100,16 +99,16 @@ func printFromTree(ctx context.Context, tree *restic.Tree, repo restic.Repositor
if err != nil {
return errors.Wrapf(err, "cannot load subtree for %q", item)
}
return printFromTree(ctx, subtree, repo, item, pathComponents[1:])
return printFromTree(ctx, subtree, repo, item, pathComponents[1:], writeDump)
case dump.IsDir(node):
if err := checkStdoutTar(); err != nil {
if err := checkStdoutArchive(); err != nil {
return err
}
subtree, err := repo.LoadTree(ctx, *node.Subtree)
if err != nil {
return err
}
return dump.WriteTar(ctx, repo, subtree, item, os.Stdout)
return writeDump(ctx, repo, subtree, item, os.Stdout)
case l > 1:
return fmt.Errorf("%q should be a dir, but is a %q", item, node.Type)
case !dump.IsFile(node):
@ -176,7 +175,7 @@ func runDump(opts DumpOptions, gopts GlobalOptions, args []string) error {
Exitf(2, "loading tree for snapshot %q failed: %v", snapshotIDString, err)
}
err = printFromTree(ctx, tree, repo, "/", splittedPath)
err = printFromTree(ctx, tree, repo, "/", splittedPath, dump.WriteTar)
if err != nil {
Exitf(2, "cannot dump file: %v", err)
}
@ -184,7 +183,7 @@ func runDump(opts DumpOptions, gopts GlobalOptions, args []string) error {
return nil
}
func checkStdoutTar() error {
func checkStdoutArchive() error {
if stdoutIsTerminal() {
return fmt.Errorf("stdout is the terminal, please redirect output")
}

104
internal/dump/common.go Normal file
View file

@ -0,0 +1,104 @@
package dump
import (
"context"
"io"
"path"
"github.com/restic/restic/internal/errors"
"github.com/restic/restic/internal/restic"
"github.com/restic/restic/internal/walker"
)
// dumper implements saving node data.
type dumper interface {
dumpNode(ctx context.Context, node *restic.Node, repo restic.Repository) error
}
// WriteDump will write the contents of the given tree to the given destination.
// It will loop over all nodes in the tree and dump them recursively.
type WriteDump func(ctx context.Context, repo restic.Repository, tree *restic.Tree, rootPath string, dst io.Writer) error
func writeDump(ctx context.Context, repo restic.Repository, tree *restic.Tree, rootPath string, dmp dumper, dst io.Writer) error {
for _, rootNode := range tree.Nodes {
rootNode.Path = rootPath
err := dumpTree(ctx, repo, rootNode, rootPath, dmp)
if err != nil {
return err
}
}
return nil
}
func dumpTree(ctx context.Context, repo restic.Repository, rootNode *restic.Node, rootPath string, dmp dumper) error {
rootNode.Path = path.Join(rootNode.Path, rootNode.Name)
rootPath = rootNode.Path
if err := dmp.dumpNode(ctx, 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 := dmp.dumpNode(ctx, node, repo)
if err != nil {
return false, err
}
}
return false, nil
})
return err
}
// 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"
}

View file

@ -5,65 +5,31 @@ import (
"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()
type tarDumper struct {
w *tar.Writer
}
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
// Statically ensure that tarDumper implements dumper.
var _ dumper = tarDumper{}
if err := tarNode(ctx, tw, rootNode, repo); err != nil {
// WriteTar will write the contents of the given tree, encoded as a tar to the given destination.
func WriteTar(ctx context.Context, repo restic.Repository, tree *restic.Tree, rootPath string, dst io.Writer) error {
dmp := tarDumper{w: tar.NewWriter(dst)}
err := writeDump(ctx, repo, tree, rootPath, dmp, dst)
if err != nil {
dmp.w.Close()
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
return dmp.w.Close()
}
// copied from archive/tar.FileInfoHeader
@ -75,7 +41,7 @@ const (
c_ISVTX = 01000 // Save text (sticky bit)
)
func tarNode(ctx context.Context, tw *tar.Writer, node *restic.Node, repo restic.Repository) error {
func (dmp tarDumper) dumpNode(ctx context.Context, node *restic.Node, repo restic.Repository) error {
relPath, err := filepath.Rel("/", node.Path)
if err != nil {
return err
@ -120,13 +86,13 @@ func tarNode(ctx context.Context, tw *tar.Writer, node *restic.Node, repo restic
header.Name += "/"
}
err = tw.WriteHeader(header)
err = dmp.w.WriteHeader(header)
if err != nil {
return errors.Wrap(err, "TarHeader ")
}
return GetNodeData(ctx, tw, repo, node)
return GetNodeData(ctx, dmp.w, repo, node)
}
func parseXattrs(xattrs []restic.ExtendedAttribute) map[string]string {
@ -146,7 +112,6 @@ func parseXattrs(xattrs []restic.ExtendedAttribute) map[string]string {
tmpMap["SCHILY.acl.default"] = na.String()
}
}
} else {
tmpMap["SCHILY.xattr."+attr.Name] = attrString
}
@ -154,39 +119,3 @@ func parseXattrs(xattrs []restic.ExtendedAttribute) map[string]string {
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"
}