예제 #1
0
파일: daemon.go 프로젝트: beginnor/docker
func NewDaemonFromDirectory(config *Config, eng *engine.Engine) (*Daemon, error) {
	// Apply configuration defaults
	if config.Mtu == 0 {
		// FIXME: GetDefaultNetwork Mtu doesn't need to be public anymore
		config.Mtu = GetDefaultNetworkMtu()
	}
	// Check for mutually incompatible config options
	if config.BridgeIface != "" && config.BridgeIP != "" {
		return nil, fmt.Errorf("You specified -b & --bip, mutually exclusive options. Please specify only one.")
	}
	if !config.EnableIptables && !config.InterContainerCommunication {
		return nil, fmt.Errorf("You specified --iptables=false with --icc=false. ICC uses iptables to function. Please set --icc or --iptables to true.")
	}
	// FIXME: DisableNetworkBidge doesn't need to be public anymore
	config.DisableNetwork = config.BridgeIface == DisableNetworkBridge

	// Claim the pidfile first, to avoid any and all unexpected race conditions.
	// Some of the init doesn't need a pidfile lock - but let's not try to be smart.
	if config.Pidfile != "" {
		if err := utils.CreatePidFile(config.Pidfile); err != nil {
			return nil, err
		}
		eng.OnShutdown(func() {
			// Always release the pidfile last, just in case
			utils.RemovePidFile(config.Pidfile)
		})
	}

	// Check that the system is supported and we have sufficient privileges
	// FIXME: return errors instead of calling Fatal
	if runtime.GOOS != "linux" {
		log.Fatalf("The Docker daemon is only supported on linux")
	}
	if os.Geteuid() != 0 {
		log.Fatalf("The Docker daemon needs to be run as root")
	}
	if err := checkKernelAndArch(); err != nil {
		log.Fatalf(err.Error())
	}

	// set up the TempDir to use a canonical path
	tmp, err := utils.TempDir(config.Root)
	if err != nil {
		log.Fatalf("Unable to get the TempDir under %s: %s", config.Root, err)
	}
	realTmp, err := utils.ReadSymlinkedDirectory(tmp)
	if err != nil {
		log.Fatalf("Unable to get the full path to the TempDir (%s): %s", tmp, err)
	}
	os.Setenv("TMPDIR", realTmp)
	if !config.EnableSelinuxSupport {
		selinuxSetDisabled()
	}

	// get the canonical path to the Docker root directory
	var realRoot string
	if _, err := os.Stat(config.Root); err != nil && os.IsNotExist(err) {
		realRoot = config.Root
	} else {
		realRoot, err = utils.ReadSymlinkedDirectory(config.Root)
		if err != nil {
			log.Fatalf("Unable to get the full path to root (%s): %s", config.Root, err)
		}
	}
	config.Root = realRoot
	// Create the root directory if it doesn't exists
	if err := os.MkdirAll(config.Root, 0700); err != nil && !os.IsExist(err) {
		return nil, err
	}

	// Set the default driver
	graphdriver.DefaultDriver = config.GraphDriver

	// Load storage driver
	driver, err := graphdriver.New(config.Root, config.GraphOptions)
	if err != nil {
		return nil, err
	}
	log.Debugf("Using graph driver %s", driver)

	// As Docker on btrfs and SELinux are incompatible at present, error on both being enabled
	if config.EnableSelinuxSupport && driver.String() == "btrfs" {
		return nil, fmt.Errorf("SELinux is not supported with the BTRFS graph driver!")
	}

	daemonRepo := path.Join(config.Root, "containers")

	if err := os.MkdirAll(daemonRepo, 0700); err != nil && !os.IsExist(err) {
		return nil, err
	}

	// Migrate the container if it is aufs and aufs is enabled
	if err = migrateIfAufs(driver, config.Root); err != nil {
		return nil, err
	}

	log.Debugf("Creating images graph")
	g, err := graph.NewGraph(path.Join(config.Root, "graph"), driver)
	if err != nil {
		return nil, err
	}

	// We don't want to use a complex driver like aufs or devmapper
	// for volumes, just a plain filesystem
	volumesDriver, err := graphdriver.GetDriver("vfs", config.Root, config.GraphOptions)
	if err != nil {
		return nil, err
	}
	log.Debugf("Creating volumes graph")
	volumes, err := graph.NewGraph(path.Join(config.Root, "volumes"), volumesDriver)
	if err != nil {
		return nil, err
	}
	log.Debugf("Creating repository list")
	repositories, err := graph.NewTagStore(path.Join(config.Root, "repositories-"+driver.String()), g)
	if err != nil {
		return nil, fmt.Errorf("Couldn't create Tag store: %s", err)
	}

	if !config.DisableNetwork {
		job := eng.Job("init_networkdriver")

		job.SetenvBool("EnableIptables", config.EnableIptables)
		job.SetenvBool("InterContainerCommunication", config.InterContainerCommunication)
		job.SetenvBool("EnableIpForward", config.EnableIpForward)
		job.Setenv("BridgeIface", config.BridgeIface)
		job.Setenv("BridgeIP", config.BridgeIP)
		job.Setenv("DefaultBindingIP", config.DefaultIp.String())

		if err := job.Run(); err != nil {
			return nil, err
		}
	}

	graphdbPath := path.Join(config.Root, "linkgraph.db")
	graph, err := graphdb.NewSqliteConn(graphdbPath)
	if err != nil {
		return nil, err
	}

	localCopy := path.Join(config.Root, "init", fmt.Sprintf("dockerinit-%s", dockerversion.VERSION))
	sysInitPath := utils.DockerInitPath(localCopy)
	if sysInitPath == "" {
		return nil, fmt.Errorf("Could not locate dockerinit: This usually means docker was built incorrectly. See http://docs.docker.com/contributing/devenvironment for official build instructions.")
	}

	if sysInitPath != localCopy {
		// When we find a suitable dockerinit binary (even if it's our local binary), we copy it into config.Root at localCopy for future use (so that the original can go away without that being a problem, for example during a package upgrade).
		if err := os.Mkdir(path.Dir(localCopy), 0700); err != nil && !os.IsExist(err) {
			return nil, err
		}
		if _, err := utils.CopyFile(sysInitPath, localCopy); err != nil {
			return nil, err
		}
		if err := os.Chmod(localCopy, 0700); err != nil {
			return nil, err
		}
		sysInitPath = localCopy
	}

	sysInfo := sysinfo.New(false)
	ed, err := execdrivers.NewDriver(config.ExecDriver, config.Root, sysInitPath, sysInfo)
	if err != nil {
		return nil, err
	}

	daemon := &Daemon{
		repository:     daemonRepo,
		containers:     &contStore{s: make(map[string]*Container)},
		graph:          g,
		repositories:   repositories,
		idIndex:        truncindex.NewTruncIndex([]string{}),
		sysInfo:        sysInfo,
		volumes:        volumes,
		config:         config,
		containerGraph: graph,
		driver:         driver,
		sysInitPath:    sysInitPath,
		execDriver:     ed,
		eng:            eng,
	}
	if err := daemon.checkLocaldns(); err != nil {
		return nil, err
	}
	if err := daemon.restore(); err != nil {
		return nil, err
	}
	// Setup shutdown handlers
	// FIXME: can these shutdown handlers be registered closer to their source?
	eng.OnShutdown(func() {
		// FIXME: if these cleanup steps can be called concurrently, register
		// them as separate handlers to speed up total shutdown time
		// FIXME: use engine logging instead of log.Errorf
		if err := daemon.shutdown(); err != nil {
			log.Errorf("daemon.shutdown(): %s", err)
		}
		if err := portallocator.ReleaseAll(); err != nil {
			log.Errorf("portallocator.ReleaseAll(): %s", err)
		}
		if err := daemon.driver.Cleanup(); err != nil {
			log.Errorf("daemon.driver.Cleanup(): %s", err.Error())
		}
		if err := daemon.containerGraph.Close(); err != nil {
			log.Errorf("daemon.containerGraph.Close(): %s", err.Error())
		}
	})

	return daemon, nil
}