Method criuSwrk

libcontainer/criu_linux.go:903–1081

(process *Process, req *criurpc.CriuReq, opts *CriuOpts, extraFiles []*os.File)

}

func (c *Container) criuSwrk(process *Process, req *criurpc.CriuReq, opts *CriuOpts, extraFiles []*os.File) error {
	fds, err := unix.Socketpair(unix.AF_LOCAL, unix.SOCK_SEQPACKET|unix.SOCK_CLOEXEC, 0)
	if err != nil {
		return err
	}

	criuClient := os.NewFile(uintptr(fds[0]), "criu-transport-client")
	criuClientFileCon, err := net.FileConn(criuClient)
	criuClient.Close()
	if err != nil {
		return err
	}

	criuClientCon := criuClientFileCon.(*net.UnixConn)
	defer criuClientCon.Close()

	criuServer := os.NewFile(uintptr(fds[1]), "criu-transport-server")
	defer criuServer.Close()

	if c.criuVersion != 0 {
		// If the CRIU Version is still '0' then this is probably
		// the initial CRIU run to detect the version. Skip it.
		logrus.Debugf("Using CRIU %d", c.criuVersion)
	}
	cmd := exec.Command("criu", "swrk", "3")
	if process != nil {
		cmd.Stdin = process.Stdin
		cmd.Stdout = process.Stdout
		cmd.Stderr = process.Stderr
	}
	cmd.ExtraFiles = append(cmd.ExtraFiles, criuServer)
	if extraFiles != nil {
		cmd.ExtraFiles = append(cmd.ExtraFiles, extraFiles...)
	}

	if err := cmd.Start(); err != nil {
		return err
	}
	// we close criuServer so that even if CRIU crashes or unexpectedly exits, runc will not hang.
	criuServer.Close()
	// cmd.Process will be replaced by a restored init.
	criuProcess := cmd.Process

	var criuProcessState *os.ProcessState
	defer func() {
		if criuProcessState == nil {
			criuClientCon.Close()
			_, err := criuProcess.Wait()
			if err != nil {
				logrus.Warnf("wait on criuProcess returned %v", err)
			}
		}
	}()

	if err := c.criuApplyCgroups(criuProcess.Pid, req); err != nil {
		return err
	}