Function newFileFD

pkg/sentry/fsimpl/tmpfs/tmpfs_test.go:59–83

newFileFD creates a new file in a new tmpfs mount, and returns the FD. If the returned err is not nil, then cleanup should be called when the FD is no longer needed.

(ctx context.Context, mode linux.FileMode)

// the returned err is not nil, then cleanup should be called when the FD is no
// longer needed.
func newFileFD(ctx context.Context, mode linux.FileMode) (*vfs.FileDescription, func(), error) {
	creds := auth.CredentialsFromContext(ctx)
	vfsObj, root, cleanup, err := newTmpfsRoot(ctx)
	if err != nil {
		return nil, nil, err
	}

	filename := fmt.Sprintf("tmpfs-test-file-%d", nextFileID.Add(1))

	// Create the file that will be write/read.
	fd, err := vfsObj.OpenAt(ctx, creds, &vfs.PathOperation{
		Root:  root,
		Start: root,
		Path:  fspath.Parse(filename),
	}, &vfs.OpenOptions{
		Flags: linux.O_RDWR | linux.O_CREAT | linux.O_EXCL,
		Mode:  linux.ModeRegular | mode,
	})
	if err != nil {
		cleanup()
		return nil, nil, fmt.Errorf("failed to create file %q: %v", filename, err)
	}

	return fd, cleanup, nil
}

// newDirFD is like newFileFD, but for directories.
func newDirFD(ctx context.Context, mode linux.FileMode) (*vfs.FileDescription, func(), error) {