Golang utils.Go函数代码示例

func (b *buildFile) run(c *Container) error {
	var errCh chan error
	if b.verbose {
		errCh = utils.Go(func() error {
			// FIXME: call the 'attach' job so that daemon.Attach can be made private
			//
			// FIXME (LK4D4): Also, maybe makes sense to call "logs" job, it is like attach
			// but without hijacking for stdin. Also, with attach there can be race
			// condition because of some output already was printed before it.
			return <-b.daemon.Attach(c, nil, nil, b.outStream, b.errStream)
		})
	}

	//start the container
	if err := c.Start(); err != nil {
		return err
	}

	if errCh != nil {
		if err := <-errCh; err != nil {
			return err
		}
	}

	// Wait for it to finish
	if ret, _ := c.State.WaitStop(-1 * time.Second); ret != 0 {
		err := &utils.JSONError{
			Message: fmt.Sprintf("The command %v returned a non-zero code: %d", b.config.Cmd, ret),
			Code:    ret,
		}
		return err
	}

	return nil
}

func (container *Container) waitForStart() error {
	callback := func(command *execdriver.Command) {
		if command.Tty {
			// The callback is called after the process Start()
			// so we are in the parent process. In TTY mode, stdin/out/err is the PtySlace
			// which we close here.
			if c, ok := command.Stdout.(io.Closer); ok {
				c.Close()
			}
		}
		container.State.SetRunning(command.Pid())
		if err := container.ToDisk(); err != nil {
			utils.Debugf("%s", err)
		}
	}

	// We use a callback here instead of a goroutine and an chan for
	// syncronization purposes
	cErr := utils.Go(func() error { return container.monitor(callback) })

	waitStart := make(chan struct{})

	go func() {
		container.State.WaitRunning(-1 * time.Second)
		close(waitStart)
	}()

	// Start should not return until the process is actually running
	select {
	case <-waitStart:
	case err := <-cErr:
		return err
	}
	return nil
}

func (b *buildFile) run(c *daemon.Container) error {
	var errCh chan error
	if b.verbose {
		errCh = utils.Go(func() error {
			return <-b.daemon.Attach(c, nil, nil, b.outStream, b.errStream)
		})
	}

	//start the container
	if err := c.Start(); err != nil {
		return err
	}

	if errCh != nil {
		if err := <-errCh; err != nil {
			return err
		}
	}

	// Wait for it to finish
	if ret, _ := c.State.WaitStop(-1 * time.Second); ret != 0 {
		err := &utils.JSONError{
			Message: fmt.Sprintf("The command %v returned a non-zero code: %d", b.config.Cmd, ret),
			Code:    ret,
		}
		return err
	}

	return nil
}

func (container *Container) Exec(execConfig *execConfig) error {
	container.Lock()
	defer container.Unlock()

	waitStart := make(chan struct{})

	callback := func(processConfig *execdriver.ProcessConfig, pid int) {
		if processConfig.Tty {
			// The callback is called after the process Start()
			// so we are in the parent process. In TTY mode, stdin/out/err is the PtySlace
			// which we close here.
			if c, ok := processConfig.Stdout.(io.Closer); ok {
				c.Close()
			}
		}
		close(waitStart)
	}

	// We use a callback here instead of a goroutine and an chan for
	// syncronization purposes
	cErr := utils.Go(func() error { return container.monitorExec(execConfig, callback) })

	// Exec should not return until the process is actually running
	select {
	case <-waitStart:
	case err := <-cErr:
		return err
	}

	return nil
}

func (container *Container) waitForStart() error {
	container.monitor = newContainerMonitor(container, container.hostConfig.RestartPolicy)

	// block until we either receive an error from the initial start of the container's
	// process or until the process is running in the container
	select {
	case <-container.monitor.startSignal:
	case err := <-utils.Go(container.monitor.Start):
		return err
	}

	return nil
}

// CopyFileWithTar emulates the behavior of the 'cp' command-line
// for a single file. It copies a regular file from path `src` to
// path `dst`, and preserves all its metadata.
//
// If `dst` ends with a trailing slash '/', the final destination path
// will be `dst/base(src)`.
func CopyFileWithTar(src, dst string) (err error) {
	utils.Debugf("CopyFileWithTar(%s, %s)", src, dst)
	srcSt, err := os.Stat(src)
	if err != nil {
		return err
	}
	if srcSt.IsDir() {
		return fmt.Errorf("Can't copy a directory")
	}
	// Clean up the trailing /
	if dst[len(dst)-1] == '/' {
		dst = path.Join(dst, filepath.Base(src))
	}
	// Create the holding directory if necessary
	if err := os.MkdirAll(filepath.Dir(dst), 0700); err != nil && !os.IsExist(err) {
		return err
	}

	r, w := io.Pipe()
	errC := utils.Go(func() error {
		defer w.Close()

		srcF, err := os.Open(src)
		if err != nil {
			return err
		}
		defer srcF.Close()

		hdr, err := tar.FileInfoHeader(srcSt, "")
		if err != nil {
			return err
		}
		hdr.Name = filepath.Base(dst)
		tw := tar.NewWriter(w)
		defer tw.Close()
		if err := tw.WriteHeader(hdr); err != nil {
			return err
		}
		if _, err := io.Copy(tw, srcF); err != nil {
			return err
		}
		return nil
	})
	defer func() {
		if er := <-errC; err != nil {
			err = er
		}
	}()
	return Untar(r, filepath.Dir(dst), nil)
}

//.........这里部分代码省略.........
			cStdout = p
			go func() {
				log.Debugf("attach: stdout: begin")
				defer log.Debugf("attach: stdout: end")
				// If we are in StdinOnce mode, then close stdin
				if stdinOnce && stdin != nil {
					defer stdin.Close()
				}
				if stdinCloser != nil {
					defer stdinCloser.Close()
				}
				_, err := io.Copy(stdout, cStdout)
				if err == io.ErrClosedPipe {
					err = nil
				}
				if err != nil {
					log.Errorf("attach: stdout: %s", err)
				}
				errors <- err
			}()
		}
	} else {
		// Point stdout of container to a no-op writer.
		go func() {
			if stdinCloser != nil {
				defer stdinCloser.Close()
			}
			if cStdout, err := streamConfig.StdoutPipe(); err != nil {
				log.Errorf("attach: stdout pipe: %s", err)
			} else {
				io.Copy(&ioutils.NopWriter{}, cStdout)
			}
		}()
	}
	if stderr != nil {
		nJobs++
		if p, err := streamConfig.StderrPipe(); err != nil {
			errors <- err
		} else {
			cStderr = p
			go func() {
				log.Debugf("attach: stderr: begin")
				defer log.Debugf("attach: stderr: end")
				// If we are in StdinOnce mode, then close stdin
				// Why are we closing stdin here and above while handling stdout?
				if stdinOnce && stdin != nil {
					defer stdin.Close()
				}
				if stdinCloser != nil {
					defer stdinCloser.Close()
				}
				_, err := io.Copy(stderr, cStderr)
				if err == io.ErrClosedPipe {
					err = nil
				}
				if err != nil {
					log.Errorf("attach: stderr: %s", err)
				}
				errors <- err
			}()
		}
	} else {
		// Point stderr at a no-op writer.
		go func() {
			if stdinCloser != nil {
				defer stdinCloser.Close()
			}

			if cStderr, err := streamConfig.StderrPipe(); err != nil {
				log.Errorf("attach: stdout pipe: %s", err)
			} else {
				io.Copy(&ioutils.NopWriter{}, cStderr)
			}
		}()
	}

	return utils.Go(func() error {
		defer func() {
			if cStdout != nil {
				cStdout.Close()
			}
			if cStderr != nil {
				cStderr.Close()
			}
		}()

		// FIXME: how to clean up the stdin goroutine without the unwanted side effect
		// of closing the passed stdin? Add an intermediary io.Pipe?
		for i := 0; i < nJobs; i++ {
			log.Debugf("attach: waiting for job %d/%d", i+1, nJobs)
			if err := <-errors; err != nil {
				log.Errorf("attach: job %d returned error %s, aborting all jobs", i+1, err)
				return err
			}
			log.Debugf("attach: job %d completed successfully", i+1)
		}
		log.Debugf("attach: all jobs completed successfully")
		return nil
	})
}

//.........这里部分代码省略.........
		if p, err := container.StdoutPipe(); err != nil {
			errors <- err
		} else {
			cStdout = p
			go func() {
				log.Debugf("attach: stdout: begin")
				defer log.Debugf("attach: stdout: end")
				// If we are in StdinOnce mode, then close stdin
				if container.Config.StdinOnce && stdin != nil {
					defer stdin.Close()
				}
				if stdinCloser != nil {
					defer stdinCloser.Close()
				}
				_, err := io.Copy(stdout, cStdout)
				if err == io.ErrClosedPipe {
					err = nil
				}
				if err != nil {
					log.Errorf("attach: stdout: %s", err)
				}
				errors <- err
			}()
		}
	} else {
		go func() {
			if stdinCloser != nil {
				defer stdinCloser.Close()
			}
			if cStdout, err := container.StdoutPipe(); err != nil {
				log.Errorf("attach: stdout pipe: %s", err)
			} else {
				io.Copy(&utils.NopWriter{}, cStdout)
			}
		}()
	}
	if stderr != nil {
		nJobs += 1
		if p, err := container.StderrPipe(); err != nil {
			errors <- err
		} else {
			cStderr = p
			go func() {
				log.Debugf("attach: stderr: begin")
				defer log.Debugf("attach: stderr: end")
				// If we are in StdinOnce mode, then close stdin
				if container.Config.StdinOnce && stdin != nil {
					defer stdin.Close()
				}
				if stdinCloser != nil {
					defer stdinCloser.Close()
				}
				_, err := io.Copy(stderr, cStderr)
				if err == io.ErrClosedPipe {
					err = nil
				}
				if err != nil {
					log.Errorf("attach: stderr: %s", err)
				}
				errors <- err
			}()
		}
	} else {
		go func() {
			if stdinCloser != nil {
				defer stdinCloser.Close()
			}

			if cStderr, err := container.StderrPipe(); err != nil {
				log.Errorf("attach: stdout pipe: %s", err)
			} else {
				io.Copy(&utils.NopWriter{}, cStderr)
			}
		}()
	}

	return utils.Go(func() error {
		defer func() {
			if cStdout != nil {
				cStdout.Close()
			}
			if cStderr != nil {
				cStderr.Close()
			}
		}()

		// FIXME: how to clean up the stdin goroutine without the unwanted side effect
		// of closing the passed stdin? Add an intermediary io.Pipe?
		for i := 0; i < nJobs; i += 1 {
			log.Debugf("attach: waiting for job %d/%d", i+1, nJobs)
			if err := <-errors; err != nil {
				log.Errorf("attach: job %d returned error %s, aborting all jobs", i+1, err)
				return err
			}
			log.Debugf("attach: job %d completed successfully", i+1)
		}
		log.Debugf("attach: all jobs completed successfully")
		return nil
	})
}

func (cli *DockerCli) hijack(method, path string, setRawTerminal bool, in io.ReadCloser, stdout, stderr io.Writer, started chan io.Closer, data interface{}) error {
	defer func() {
		if started != nil {
			close(started)
		}
	}()

	params, err := cli.encodeData(data)
	if err != nil {
		return err
	}
	req, err := http.NewRequest(method, fmt.Sprintf("/v%s%s", api.APIVERSION, path), params)
	if err != nil {
		return err
	}
	req.Header.Set("User-Agent", "Docker-Client/"+dockerversion.VERSION)
	req.Header.Set("Content-Type", "plain/text")
	req.Host = cli.addr

	dial, err := cli.dial()
	if err != nil {
		if strings.Contains(err.Error(), "connection refused") {
			return fmt.Errorf("Cannot connect to the Docker daemon. Is 'docker -d' running on this host?")
		}
		return err
	}
	clientconn := httputil.NewClientConn(dial, nil)
	defer clientconn.Close()

	// Server hijacks the connection, error 'connection closed' expected
	clientconn.Do(req)

	rwc, br := clientconn.Hijack()
	defer rwc.Close()

	if started != nil {
		started <- rwc
	}

	var receiveStdout chan error

	var oldState *term.State

	if in != nil && setRawTerminal && cli.isTerminalIn && os.Getenv("NORAW") == "" {
		oldState, err = term.SetRawTerminal(cli.inFd)
		if err != nil {
			return err
		}
		defer term.RestoreTerminal(cli.inFd, oldState)
	}

	if stdout != nil || stderr != nil {
		receiveStdout = utils.Go(func() (err error) {
			defer func() {
				if in != nil {
					if setRawTerminal && cli.isTerminalIn {
						term.RestoreTerminal(cli.inFd, oldState)
					}
					// For some reason this Close call blocks on darwin..
					// As the client exists right after, simply discard the close
					// until we find a better solution.
					if runtime.GOOS != "darwin" {
						in.Close()
					}
				}
			}()

			// When TTY is ON, use regular copy
			if setRawTerminal && stdout != nil {
				_, err = io.Copy(stdout, br)
			} else {
				_, err = stdcopy.StdCopy(stdout, stderr, br)
			}
			log.Debugf("[hijack] End of stdout")
			return err
		})
	}

	sendStdin := utils.Go(func() error {
		if in != nil {
			io.Copy(rwc, in)
			log.Debugf("[hijack] End of stdin")
		}
		if tcpc, ok := rwc.(*net.TCPConn); ok {
			if err := tcpc.CloseWrite(); err != nil {
				log.Debugf("Couldn't send EOF: %s", err)
			}
		} else if unixc, ok := rwc.(*net.UnixConn); ok {
			if err := unixc.CloseWrite(); err != nil {
				log.Debugf("Couldn't send EOF: %s", err)
			}
		}
		// Discard errors due to pipe interruption
		return nil
	})

	if stdout != nil || stderr != nil {
		if err := <-receiveStdout; err != nil {
			log.Debugf("Error receiveStdout: %s", err)
			return err
//.........这里部分代码省略.........