Files
cloudsave/pkg/tools/archive/archive.go
2025-07-30 15:14:01 +02:00

125 lines
2.3 KiB
Go

package archive
import (
"archive/tar"
"compress/gzip"
"fmt"
"io"
"os"
"path/filepath"
)
func Untar(file io.Reader, path string) error {
gzr, err := gzip.NewReader(file)
if err != nil {
return err
}
defer gzr.Close()
tr := tar.NewReader(gzr)
for {
header, err := tr.Next()
switch {
// if no more files are found return
case err == io.EOF:
return nil
// return any other error
case err != nil:
return err
// if the header is nil, just skip it (not sure how this happens)
case header == nil:
continue
}
// the target location where the dir/file should be created
target := filepath.Join(path, header.Name)
// the following switch could also be done using fi.Mode(), not sure if there
// a benefit of using one vs. the other.
// fi := header.FileInfo()
// check the file type
switch header.Typeflag {
// if its a dir and it doesn't exist create it
case tar.TypeDir:
if _, err := os.Stat(target); err != nil {
if err := os.MkdirAll(target, 0755); err != nil {
return err
}
}
// if it's a file create it
case tar.TypeReg:
f, err := os.OpenFile(target, os.O_CREATE|os.O_RDWR, os.FileMode(header.Mode))
if err != nil {
return err
}
// copy over contents
if _, err := io.Copy(f, tr); err != nil {
return err
}
// manually close here after each file operation; defering would cause each file close
// to wait until all operations have completed.
f.Close()
}
}
}
func Tar(file io.Writer, root string) error {
gw := gzip.NewWriter(file)
defer gw.Close()
tw := tar.NewWriter(gw)
defer tw.Close()
// Walk again to add files
err := filepath.Walk(root, func(path string, info os.FileInfo, walkErr error) error {
if walkErr != nil {
return walkErr
}
path, err := filepath.Rel(root, path)
if err != nil {
return err
}
// Create tar header
header, err := tar.FileInfoHeader(info, path)
if err != nil {
return err
}
header.Name = path
if err := tw.WriteHeader(header); err != nil {
return err
}
if !info.Mode().IsRegular() {
return nil
}
file, err := os.Open(path)
if err != nil {
return err
}
defer file.Close()
if _, err := io.Copy(tw, file); err != nil {
return err
}
return nil
})
if err != nil {
return fmt.Errorf("writing tar entries: %w", err)
}
return nil
}