// AttachStreams is called by libcontainerd to connect the stdio.
func (daemon *Daemon) AttachStreams(id string, iop libcontainerd.IOPipe) error {
	var (
		s  *runconfig.StreamConfig
		ec *exec.Config
	)

	c := daemon.containers.Get(id)
	if c == nil {
		var err error
		ec, err = daemon.getExecConfig(id)
		if err != nil {
			return fmt.Errorf("no such exec/container: %s", id)
		}
		s = ec.StreamConfig
	} else {
		s = c.StreamConfig
		if err := daemon.StartLogging(c); err != nil {
			c.Reset(false)
			return err
		}
	}

	copyFunc := func(w io.Writer, r io.Reader) {
		s.Add(1)
		go func() {
			if _, err := io.Copy(w, r); err != nil {
				logrus.Errorf("%v stream copy error: %v", id, err)
			}
			s.Done()
		}()
	}

	if iop.Stdout != nil {
		copyFunc(s.Stdout(), iop.Stdout)
	}
	if iop.Stderr != nil {
		copyFunc(s.Stderr(), iop.Stderr)
	}

	if stdin := s.Stdin(); stdin != nil {
		if iop.Stdin != nil {
			go func() {
				io.Copy(iop.Stdin, stdin)
				iop.Stdin.Close()
			}()
		}
	} else {
		//TODO(swernli): On Windows, not closing stdin when no tty is requested by the exec Config
		// results in a hang. We should re-evaluate generalizing this fix for all OSes if
		// we can determine that is the right thing to do more generally.
		if (c != nil && !c.Config.Tty) || (ec != nil && !ec.Tty && runtime.GOOS == "windows") {
			// tty is enabled, so dont close containerd's iopipe stdin.
			if iop.Stdin != nil {
				iop.Stdin.Close()
			}
		}
	}

	return nil
}

// AttachStreams connects streams to a TTY.
// Used by exec too. Should this move somewhere else?
func AttachStreams(ctx context.Context, streamConfig *runconfig.StreamConfig, openStdin, stdinOnce, tty bool, stdin io.ReadCloser, stdout io.Writer, stderr io.Writer, keys []byte) chan error {
	var (
		cStdout, cStderr io.ReadCloser
		cStdin           io.WriteCloser
		wg               sync.WaitGroup
		errors           = make(chan error, 3)
	)

	if stdin != nil && openStdin {
		cStdin = streamConfig.StdinPipe()
		wg.Add(1)
	}

	if stdout != nil {
		cStdout = streamConfig.StdoutPipe()
		wg.Add(1)
	}

	if stderr != nil {
		cStderr = streamConfig.StderrPipe()
		wg.Add(1)
	}

	// Connect stdin of container to the http conn.
	go func() {
		if stdin == nil || !openStdin {
			return
		}
		logrus.Debug("attach: stdin: begin")

		var err error
		if tty {
			_, err = copyEscapable(cStdin, stdin, keys)
		} else {
			_, err = io.Copy(cStdin, stdin)
		}
		if err == io.ErrClosedPipe {
			err = nil
		}
		if err != nil {
			logrus.Errorf("attach: stdin: %s", err)
			errors <- err
		}
		if stdinOnce && !tty {
			cStdin.Close()
		} else {
			// No matter what, when stdin is closed (io.Copy unblock), close stdout and stderr
			if cStdout != nil {
				cStdout.Close()
			}
			if cStderr != nil {
				cStderr.Close()
			}
		}
		logrus.Debug("attach: stdin: end")
		wg.Done()
	}()

	attachStream := func(name string, stream io.Writer, streamPipe io.ReadCloser) {
		if stream == nil {
			return
		}

		logrus.Debugf("attach: %s: begin", name)
		_, err := io.Copy(stream, streamPipe)
		if err == io.ErrClosedPipe {
			err = nil
		}
		if err != nil {
			logrus.Errorf("attach: %s: %v", name, err)
			errors <- err
		}
		// Make sure stdin gets closed
		if stdin != nil {
			stdin.Close()
		}
		streamPipe.Close()
		logrus.Debugf("attach: %s: end", name)
		wg.Done()
	}

	go attachStream("stdout", stdout, cStdout)
	go attachStream("stderr", stderr, cStderr)

	return promise.Go(func() error {
		done := make(chan struct{})
		go func() {
			wg.Wait()
			close(done)
		}()
		select {
		case <-done:
		case <-ctx.Done():
			// close all pipes
			if cStdin != nil {
				cStdin.Close()
			}
			if cStdout != nil {
//.........这里部分代码省略.........

// AttachStreams is called by libcontainerd to connect the stdio.
func (daemon *Daemon) AttachStreams(id string, iop libcontainerd.IOPipe) error {
	var s *runconfig.StreamConfig
	c := daemon.containers.Get(id)
	if c == nil {
		ec, err := daemon.getExecConfig(id)
		if err != nil {
			return fmt.Errorf("no such exec/container: %s", id)
		}
		s = ec.StreamConfig
	} else {
		s = c.StreamConfig
		if err := daemon.StartLogging(c); err != nil {
			c.Reset(false)
			return err
		}
	}

	if stdin := s.Stdin(); stdin != nil {
		if iop.Stdin != nil {
			go func() {
				io.Copy(iop.Stdin, stdin)
				iop.Stdin.Close()
			}()
		}
	} else {
		if c != nil && !c.Config.Tty {
			// tty is enabled, so dont close containerd's iopipe stdin.
			if iop.Stdin != nil {
				iop.Stdin.Close()
			}
		}
	}

	copy := func(w io.Writer, r io.Reader) {
		s.Add(1)
		go func() {
			if _, err := io.Copy(w, r); err != nil {
				logrus.Errorf("%v stream copy error: %v", id, err)
			}
			s.Done()
		}()
	}

	if iop.Stdout != nil {
		copy(s.Stdout(), iop.Stdout)
	}
	if iop.Stderr != nil {
		copy(s.Stderr(), iop.Stderr)
	}

	return nil
}