Golang tar.NewWriter函数代码示例

func NewReader(path path.Path, dag mdag.DAGService, dagnode *mdag.Node, compression int) (*Reader, error) {

	reader := &Reader{
		signalChan: make(chan struct{}),
		dag:        dag,
	}

	var err error
	if compression != gzip.NoCompression {
		reader.gzipWriter, err = gzip.NewWriterLevel(&reader.buf, compression)
		if err != nil {
			return nil, err
		}
		reader.writer = tar.NewWriter(reader.gzipWriter)
	} else {
		reader.writer = tar.NewWriter(&reader.buf)
	}

	// writeToBuf will write the data to the buffer, and will signal when there
	// is new data to read
	_, filename := gopath.Split(path.String())
	go reader.writeToBuf(dagnode, filename, 0)

	return reader, nil
}

func MakeTarball(tarname string, fnames []string) error {
	log.Printf("tarring %d entrires to %s ...", len(fnames), tarname)
	tarfile, err := os.Create(tarname)
	if err != nil {
		return err
	}
	defer tarfile.Close()
	var tarwriter *tar.Writer
	if strings.HasSuffix(tarname, ".gz") {
		zipper := gzip.NewWriter(tarfile)
		defer zipper.Close()
		tarwriter = tar.NewWriter(zipper)
		/*
			} else if strings.HasSuffix(tarname, ".xz") {
				p := xz.WriterDefaults
				p.DictCap = 1 << 24
				zipper, err := xz.NewWriterParams(tarfile, &p) //xz.NewWriter(tarfile)
				if err != nil {
					return err
				}
				defer zipper.Close()
				tarwriter = tar.NewWriter(zipper)
		*/
	} else {
		tarwriter = tar.NewWriter(tarfile)
	}
	defer tarwriter.Close()

	for _, fname := range fnames {
		realm, ts, good := util.Parse_FName(fname)
		if !good {
			log.Printf("warning: skip ill-named file '%s'", fname)
			continue // skip
		}
		data, err := util.Load(fname)
		if err != nil {
			return err
		}

		hdr := new(tar.Header)
		hdr.Name = util.Make_FName(realm, ts, false)
		hdr.Size = int64(len(data))
		hdr.ModTime = ts
		hdr.Mode = 0644
		err = tarwriter.WriteHeader(hdr)
		if err != nil {
			return err
		}
		log.Printf("tar %d bytes for file %s", hdr.Size, hdr.Name)
		_, err = tarwriter.Write(data)
		if err != nil {
			return err
		}
	}
	log.Printf("%s tarred without errors", tarname)
	return nil
}

func (s *uploadSuite) createArchive(c *gc.C) {
	archive, err := os.Create(s.filename)
	c.Assert(err, jc.ErrorIsNil)
	defer archive.Close()

	compressed := gzip.NewWriter(archive)
	defer compressed.Close()

	tarball := tar.NewWriter(compressed)
	defer tarball.Close()

	var files = []struct{ Name, Body string }{
		{"root.tar", "<state config files>"},
		{"dump/oplog.bson", "<something here>"},
	}
	for _, file := range files {
		hdr := &tar.Header{
			Name: file.Name,
			Size: int64(len(file.Body)),
		}
		err := tarball.WriteHeader(hdr)
		c.Assert(err, jc.ErrorIsNil)
		_, err = tarball.Write([]byte(file.Body))
		c.Assert(err, jc.ErrorIsNil)
	}
}

func (s *DockerSuite) TestBuildApiDockerfileSymlink(c *check.C) {
	// Test to make sure we stop people from trying to leave the
	// build context when specifying a symlink as the path to the dockerfile
	buffer := new(bytes.Buffer)
	tw := tar.NewWriter(buffer)
	defer tw.Close()

	if err := tw.WriteHeader(&tar.Header{
		Name:     "Dockerfile",
		Typeflag: tar.TypeSymlink,
		Linkname: "/etc/passwd",
	}); err != nil {
		c.Fatalf("failed to write tar file header: %v", err)
	}
	if err := tw.Close(); err != nil {
		c.Fatalf("failed to close tar archive: %v", err)
	}

	res, body, err := sockRequestRaw("POST", "/build", buffer, "application/x-tar")
	c.Assert(res.StatusCode, check.Equals, http.StatusInternalServerError)
	c.Assert(err, check.IsNil)

	out, err := readBody(body)
	if err != nil {
		c.Fatal(err)
	}

	// The reason the error is "Cannot locate specified Dockerfile" is because
	// in the builder, the symlink is resolved within the context, therefore
	// Dockerfile -> /etc/passwd becomes etc/passwd from the context which is
	// a nonexistent file.
	if !strings.Contains(string(out), "Cannot locate specified Dockerfile: Dockerfile") {
		c.Fatalf("Didn't complain about leaving build context: %s", out)
	}
}

// Archive writes the executable files found in the given directory in
// gzipped tar format to w.
func Archive(w io.Writer, dir string) error {
	entries, err := ioutil.ReadDir(dir)
	if err != nil {
		return err
	}

	gzw := gzip.NewWriter(w)
	defer closeErrorCheck(&err, gzw)

	tarw := tar.NewWriter(gzw)
	defer closeErrorCheck(&err, tarw)

	for _, ent := range entries {
		h := tarHeader(ent)
		logger.Debugf("adding entry: %#v", h)
		// ignore local umask
		if isExecutable(ent) {
			h.Mode = 0755
		} else {
			h.Mode = 0644
		}
		err := tarw.WriteHeader(h)
		if err != nil {
			return err
		}
		fileName := filepath.Join(dir, ent.Name())
		if err := copyFile(tarw, fileName); err != nil {
			return err
		}
	}
	return nil
}

func (c *PackCmd) Run() error {
	pkgdir := os.ExpandEnv("$GOPATH/pkg")
	c.log.Logv("Package dir: %s", pkgdir)
	files, err := ioutil.ReadDir(pkgdir)
	if err != nil {
		return err
	}

	writer := tar.NewWriter(c.writer)
	defer func() {
		if err := writer.Close(); err != nil {
			panic(err)
		}
	}()

	for _, f := range files {
		if f.IsDir() {
			c.log.Logv("OS/Arch: %s", f.Name())
			if err := c.packLib(writer, f.Name()); err == nil {
				if err = c.packSource(writer, c.Paths); err != nil {
					panic(err)
				}
			} else if os.IsNotExist(err) {
				c.log.Logv("not built")
				continue // it might not be built for this combo
			} else {
				panic(err)
			}
		}
	}

	return nil
}

func (a *Archive) writer() (*tharWriter, error) {
	writer := io.Writer(a.Stream)

	flushers := []flushableWriter{}
	closers := []closeableWriter{}

	if a.Options.GZip {
		if a.Options.GZipLevel > 0 {
			gw, err := gzip.NewWriterLevel(writer, a.Options.GZipLevel)
			if err != nil {
				return nil, err
			}

			flushers = append([]flushableWriter{gw}, flushers...)
			closers = append([]closeableWriter{gw}, closers...)
			writer = gw
		} else {
			writer = gzip.NewWriter(writer)
		}
	}

	tw := tar.NewWriter(writer)
	flushers = append([]flushableWriter{tw}, flushers...)

	return &tharWriter{
		Writer:   tw,
		Flushers: flushers,
		Closers:  closers,
	}, nil
}

// Backup will write a tar archive of any TSM files modified since the passed
// in time to the passed in writer. The basePath will be prepended to the names
// of the files in the archive. It will force a snapshot of the WAL first
// then perform the backup with a read lock against the file store. This means
// that new TSM files will not be able to be created in this shard while the
// backup is running. For shards that are still acively getting writes, this
// could cause the WAL to backup, increasing memory usage and evenutally rejecting writes.
func (e *Engine) Backup(w io.Writer, basePath string, since time.Time) error {
	if err := e.WriteSnapshot(); err != nil {
		return err
	}
	e.FileStore.mu.RLock()
	defer e.FileStore.mu.RUnlock()

	var files []FileStat

	// grab all the files and tombstones that have a modified time after since
	for _, f := range e.FileStore.files {
		if stat := f.Stats(); stat.LastModified > since.UnixNano() {
			files = append(files, f.Stats())
		}
		for _, t := range f.TombstoneFiles() {
			if t.LastModified > since.UnixNano() {
				files = append(files, f.Stats())
			}
		}
	}

	tw := tar.NewWriter(w)
	defer tw.Close()

	for _, f := range files {
		if err := e.writeFileToBackup(f, basePath, tw); err != nil {
			return err
		}
	}

	return nil
}

// newDebugInfo initializes the global debug handler.
func newDebugInfo(name string, w io.Writer) (*debugInfo, error) {
	gz := gzip.NewWriter(w)

	d := &debugInfo{
		name: name,
		w:    w,
		gz:   gz,
		tar:  tar.NewWriter(gz),
	}

	// create the subdirs we need
	topHdr := &tar.Header{
		Name:     name,
		Typeflag: tar.TypeDir,
		Mode:     0755,
	}
	graphsHdr := &tar.Header{
		Name:     name + "/graphs",
		Typeflag: tar.TypeDir,
		Mode:     0755,
	}
	err := d.tar.WriteHeader(topHdr)
	// if the first errors, the second will too
	err = d.tar.WriteHeader(graphsHdr)
	if err != nil {
		return nil, err
	}

	return d, nil
}

func newExportAction(c *cli.Context) {
	if len(c.Args()) > 1 {
		fmt.Fprintln(os.Stderr, "At most one host name could be provided.")
		os.Exit(1)
	}

	if _, err := depot.GetCertificateAuthority(d); isFileNotExist(err) {
		fmt.Fprintln(os.Stderr, "Please run 'ca-ctl init' to initial the depot.")
		os.Exit(1)
	}

	var files []*TarFile
	var err error
	if len(c.Args()) == 0 {
		files, err = getAuthFiles(c)
	} else {
		files, err = getHostFiles(c, c.Args()[0])
	}
	if err != nil {
		fmt.Fprintln(os.Stderr, err)
		os.Exit(1)
	}

	w := tar.NewWriter(os.Stdout)
	defer w.Close()
	if err = outputTarFiles(w, files); err != nil {
		fmt.Fprintln(os.Stderr, "Save tar error:", err)
		os.Exit(1)
	}
}

func newTestTar(entries []*testTarEntry, dir string) (string, error) {
	t, err := ioutil.TempFile(dir, "tar")
	if err != nil {
		return "", err
	}
	defer t.Close()
	tw := tar.NewWriter(t)
	for _, entry := range entries {
		// Add default mode
		if entry.header.Mode == 0 {
			if entry.header.Typeflag == tar.TypeDir {
				entry.header.Mode = 0755
			} else {
				entry.header.Mode = 0644
			}
		}
		// Add calling user uid and gid or tests will fail
		entry.header.Uid = os.Getuid()
		entry.header.Gid = os.Getgid()
		if err := tw.WriteHeader(entry.header); err != nil {
			return "", err
		}
		if _, err := io.WriteString(tw, entry.contents); err != nil {
			return "", err
		}
	}
	if err := tw.Close(); err != nil {
		return "", err
	}
	return t.Name(), nil
}

// createImageInput creates a tar reader using the given templates as files.
// The given vars are replaced in all the templates encountered.
func createImageInput(tmpls, vars map[string]string) (io.Reader, error) {
	var buf bytes.Buffer
	tarW := stdtar.NewWriter(&buf)
	header := &stdtar.Header{
		Mode: 0644,
	}

	for path, tmpl := range tmpls {
		if vars != nil {
			for key, val := range vars {
				tmpl = strings.Replace(tmpl, "{{"+key+"}}", val, -1)
			}
		}

		header.Name = path
		header.Size = int64(len(tmpl))
		err := tarW.WriteHeader(header)
		if err != nil {
			return nil, err
		}

		_, err = io.Copy(tarW, strings.NewReader(tmpl))
		if err != nil {
			return nil, err
		}
	}

	return &buf, tarW.Close()
}

func _tar_compress(call otto.FunctionCall) otto.Value {
	var (
		baseDir string
	)
	source, _ := call.Argument(0).ToString()
	target, _ := call.Argument(1).ToString()

	filename := filepath.Base(source)
	target = filepath.Join(target, fmt.Sprintf("%s.tar", filename))
	tarfile, err := os.Create(target)
	if err != nil {
		jsThrow(call, err)
	}
	defer tarfile.Close()

	tarball := tar.NewWriter(tarfile)
	defer tarball.Close()

	info, err := os.Stat(source)
	if err != nil {
		jsThrow(call, err)
	}

	if info.IsDir() {
		baseDir = filepath.Base(source)
	}

	err = filepath.Walk(source,
		func(path string, info os.FileInfo, err error) error {
			if err != nil {
				return err
			}

			header, err := tar.FileInfoHeader(info, info.Name())
			if err != nil {
				return err
			}

			if baseDir != "" {
				header.Name = filepath.Join(baseDir, strings.TrimPrefix(path, source))
			}

			if err := tarball.WriteHeader(header); err != nil {
				return err
			}

			if info.IsDir() {
				return nil
			}

			file, err := os.Open(path)
			if err != nil {
				return err
			}
			defer file.Close()
			_, err = io.Copy(tarball, file)
			return err
		})
	return otto.Value{}
}

func TarGZ(files []ExportFile) ([]byte, error) {
	tarBuffer := new(bytes.Buffer)
	tarWriter := tar.NewWriter(tarBuffer)

	for _, file := range files {
		header := &tar.Header{
			Name:    file.Name,
			Mode:    int64(file.Mode),
			Size:    int64(len(file.Content)),
			ModTime: time.Now(),
		}
		if err := tarWriter.WriteHeader(header); err != nil {
			return nil, err
		}
		if _, err := tarWriter.Write(file.Content); err != nil {
			return nil, err
		}
	}

	if err := tarWriter.Close(); err != nil {
		return nil, err
	}

	zipBuffer := new(bytes.Buffer)
	zipWriter := gzip.NewWriter(zipBuffer)
	zipWriter.Write(tarBuffer.Bytes())
	zipWriter.Close()

	return zipBuffer.Bytes(), nil
}

func targz(ctx *cmd.Context, destination io.Writer, filepaths ...string) error {
	var buf bytes.Buffer
	tarWriter := tar.NewWriter(&buf)
	for _, path := range filepaths {
		if path == ".." {
			fmt.Fprintf(ctx.Stderr, "Warning: skipping %q", path)
			continue
		}
		fi, err := os.Lstat(path)
		if err != nil {
			return err
		}
		if fi.IsDir() {
			if len(filepaths) == 1 && path != "." {
				return singleDir(ctx, destination, path)
			}
			err = addDir(tarWriter, path)
		} else {
			err = addFile(tarWriter, path)
		}
		if err != nil {
			return err
		}
	}
	err := tarWriter.Close()
	if err != nil {
		return err
	}
	gzipWriter := gzip.NewWriter(destination)
	defer gzipWriter.Close()
	_, err = io.Copy(gzipWriter, &buf)
	return err
}