We build too many walls and not enough bridges

pkg/updates/tar.go

@@ -0,0 +1,126 @@
+// Copyright (c) 2020 Proton Technologies AG
+//
+// This file is part of ProtonMail Bridge.
+//
+// ProtonMail Bridge is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// ProtonMail Bridge is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with ProtonMail Bridge.  If not, see <https://www.gnu.org/licenses/>.
+
+package updates
+
+import (
+	"archive/tar"
+	"compress/gzip"
+	"errors"
+	"io"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"runtime"
+
+	"github.com/sirupsen/logrus"
+)
+
+func createTar(tarPath, sourcePath string) error { //nolint[unused]
+	if runtime.GOOS != "linux" {
+		return errors.New("tar not implemented only for linux")
+	}
+	// Check whether it exists and is a directory.
+	if _, err := os.Lstat(sourcePath); err != nil {
+		return err
+	}
+
+	absPath, err := filepath.Abs(tarPath)
+	if err != nil {
+		return err
+	}
+
+	cmd := exec.Command("tar", "-zvcf", absPath, filepath.Base(sourcePath)) //nolint[gosec]
+	cmd.Dir = filepath.Dir(sourcePath)
+	cmd.Stderr = log.WriterLevel(logrus.ErrorLevel)
+	cmd.Stdout = log.WriterLevel(logrus.InfoLevel)
+	return cmd.Run()
+}
+
+func untarToDir(tarPath, targetDir string, status *Progress) error { //nolint[funlen]
+	// Check whether it exists and is a directory.
+	if ls, err := os.Lstat(targetDir); err == nil {
+		if !ls.IsDir() {
+			return errors.New("not a dir")
+		}
+	} else {
+		return err
+	}
+
+	tgzReader, err := os.Open(tarPath) //nolint[gosec]
+	if err != nil {
+		return err
+	}
+	defer tgzReader.Close() //nolint[errcheck]
+
+	size := uint64(0)
+	if info, err := tgzReader.Stat(); err == nil {
+		size = uint64(info.Size())
+	}
+
+	wc := &WriteCounter{
+		Status: status,
+		Size:   size,
+	}
+
+	tarReader, err := gzip.NewReader(io.TeeReader(tgzReader, wc))
+	if err != nil {
+		return err
+	}
+
+	fileReader := tar.NewReader(tarReader)
+	for {
+		header, err := fileReader.Next()
+		if err == io.EOF {
+			break
+		}
+		if err != nil {
+			return err
+		}
+		if header == nil {
+			continue
+		}
+
+		targetFile := filepath.Join(targetDir, header.Name)
+		info := header.FileInfo()
+
+		// Create symlink.
+		if header.Typeflag == tar.TypeSymlink {
+			if header.Linkname == "" {
+				return errors.New("missing linkname")
+			}
+			if err := os.Symlink(header.Linkname, targetFile); err != nil {
+				return err
+			}
+			continue
+		}
+
+		// Handle case that it is a directory.
+		if info.IsDir() {
+			if err := os.MkdirAll(targetFile, info.Mode()); err != nil {
+				return err
+			}
+			continue
+		}
+
+		// Handle case that it is a regular file.
+		if err := copyToFileTruncate(fileReader, targetFile, info.Mode()); err != nil {
+			return err
+		}
+	}
+	return nil
+}