Golang archive.Close函数代码示例

// TarLayer returns a tar archive of the image's filesystem layer.
func (img *Image) TarLayer() (arch archive.Archive, err error) {
	if img.graph == nil {
		return nil, fmt.Errorf("Can't load storage driver for unregistered image %s", img.ID)
	}
	driver := img.graph.Driver()
	if differ, ok := driver.(graphdriver.Differ); ok {
		return differ.Diff(img.ID)
	}

	imgFs, err := driver.Get(img.ID, "")
	if err != nil {
		return nil, err
	}

	defer func() {
		if err != nil {
			driver.Put(img.ID)
		}
	}()

	if img.Parent == "" {
		archive, err := archive.Tar(imgFs, archive.Uncompressed)
		if err != nil {
			return nil, err
		}
		return utils.NewReadCloserWrapper(archive, func() error {
			err := archive.Close()
			driver.Put(img.ID)
			return err
		}), nil
	}

	parentFs, err := driver.Get(img.Parent, "")
	if err != nil {
		return nil, err
	}
	defer driver.Put(img.Parent)
	changes, err := archive.ChangesDirs(imgFs, parentFs)
	if err != nil {
		return nil, err
	}
	archive, err := archive.ExportChanges(imgFs, changes)
	if err != nil {
		return nil, err
	}
	return utils.NewReadCloserWrapper(archive, func() error {
		err := archive.Close()
		driver.Put(img.ID)
		return err
	}), nil
}

// Diff produces an archive of the changes between the specified
// layer and its parent layer which may be "".
func (gdw *naiveDiffDriver) Diff(id, parent string) (arch archive.Archive, err error) {
	driver := gdw.ProtoDriver

	layerFs, err := driver.Get(id, "")
	if err != nil {
		return nil, err
	}

	defer func() {
		if err != nil {
			driver.Put(id)
		}
	}()

	if parent == "" {
		archive, err := archive.Tar(layerFs, archive.Uncompressed)
		if err != nil {
			return nil, err
		}
		return ioutils.NewReadCloserWrapper(archive, func() error {
			err := archive.Close()
			driver.Put(id)
			return err
		}), nil
	}

	parentFs, err := driver.Get(parent, "")
	if err != nil {
		return nil, err
	}
	defer driver.Put(parent)

	changes, err := archive.ChangesDirs(layerFs, parentFs)
	if err != nil {
		return nil, err
	}

	archive, err := archive.ExportChanges(layerFs, changes)
	if err != nil {
		return nil, err
	}

	return ioutils.NewReadCloserWrapper(archive, func() error {
		err := archive.Close()
		driver.Put(id)
		return err
	}), nil
}

func (daemon *Daemon) Diff(container *Container) (archive.Archive, error) {
	if differ, ok := daemon.driver.(graphdriver.Differ); ok {
		return differ.Diff(container.ID)
	}

	changes, err := daemon.Changes(container)
	if err != nil {
		return nil, err
	}

	cDir, err := daemon.driver.Get(container.ID, "")
	if err != nil {
		return nil, fmt.Errorf("Error getting container rootfs %s from driver %s: %s", container.ID, container.daemon.driver, err)
	}

	archive, err := archive.ExportChanges(cDir, changes)
	if err != nil {
		return nil, err
	}
	return utils.NewReadCloserWrapper(archive, func() error {
		err := archive.Close()
		daemon.driver.Put(container.ID)
		return err
	}), nil
}

func (container *Container) Export() (archive.Archive, error) {
	if err := container.Mount(); err != nil {
		return nil, err
	}

	archive, err := archive.Tar(container.basefs, archive.Uncompressed)
	if err != nil {
		container.Unmount()
		return nil, err
	}
	return utils.NewReadCloserWrapper(archive, func() error {
			err := archive.Close()
			container.Unmount()
			return err
		}),
		nil
}

func (container *Container) ExportRw() (archive.Archive, error) {
	if err := container.Mount(); err != nil {
		return nil, err
	}
	if container.daemon == nil {
		return nil, fmt.Errorf("Can't load storage driver for unregistered container %s", container.ID)
	}
	archive, err := container.daemon.Diff(container)
	if err != nil {
		container.Unmount()
		return nil, err
	}
	return utils.NewReadCloserWrapper(archive, func() error {
			err := archive.Close()
			container.Unmount()
			return err
		}),
		nil
}

func (container *Container) Copy(resource string) (io.ReadCloser, error) {
	if err := container.Mount(); err != nil {
		return nil, err
	}

	var filter []string

	basePath, err := container.getResourcePath(resource)
	if err != nil {
		container.Unmount()
		return nil, err
	}

	stat, err := os.Stat(basePath)
	if err != nil {
		container.Unmount()
		return nil, err
	}
	if !stat.IsDir() {
		d, f := path.Split(basePath)
		basePath = d
		filter = []string{f}
	} else {
		filter = []string{path.Base(basePath)}
		basePath = path.Dir(basePath)
	}

	archive, err := archive.TarWithOptions(basePath, &archive.TarOptions{
		Compression: archive.Uncompressed,
		Includes:    filter,
	})
	if err != nil {
		container.Unmount()
		return nil, err
	}
	return utils.NewReadCloserWrapper(archive, func() error {
			err := archive.Close()
			container.Unmount()
			return err
		}),
		nil
}