Golang lock.SharedKeyLock函数代码示例

func (s *Store) ReadStream(key string) (io.ReadCloser, error) {
	key, err := s.ResolveKey(key)
	if err != nil {
		return nil, errwrap.Wrap(errors.New("error resolving image ID"), err)
	}
	keyLock, err := lock.SharedKeyLock(s.imageLockDir, key)
	if err != nil {
		return nil, errwrap.Wrap(errors.New("error locking image"), err)
	}
	defer keyLock.Close()

	err = s.db.Do(func(tx *sql.Tx) error {
		aciinfo, found, err := GetACIInfoWithBlobKey(tx, key)
		if err != nil {
			return errwrap.Wrap(errors.New("error getting aciinfo"), err)
		} else if !found {
			return fmt.Errorf("cannot find image with key: %s", key)
		}

		aciinfo.LastUsed = time.Now()

		return WriteACIInfo(tx, aciinfo)
	})
	if err != nil {
		return nil, errwrap.Wrap(fmt.Errorf("cannot get image info for %q from db", key), err)
	}

	return s.stores[blobType].ReadStream(key, false)
}

// CheckTreeStore verifies the treestore consistency for the specified key.
func (s Store) CheckTreeStore(key string) error {
	treeStoreKeyLock, err := lock.SharedKeyLock(s.treeStoreLockDir, key)
	if err != nil {
		return fmt.Errorf("error locking tree store: %v", err)
	}
	defer treeStoreKeyLock.Close()

	return s.treestore.Check(key)
}

// Check verifies the treestore consistency for the specified id.
func (ts *Store) Check(id string) (string, error) {
	treeStoreKeyLock, err := lock.SharedKeyLock(ts.lockDir, id)
	if err != nil {
		return "", errwrap.Wrap(errors.New("error locking tree store"), err)
	}
	defer treeStoreKeyLock.Close()

	return ts.check(id)
}

// CheckTreeStore verifies the treestore consistency for the specified id.
func (s *Store) CheckTreeStore(id string) (string, error) {
	treeStoreKeyLock, err := lock.SharedKeyLock(s.treeStoreLockDir, id)
	if err != nil {
		return "", fmt.Errorf("error locking tree store: %v", err)
	}
	defer treeStoreKeyLock.Close()

	return s.treestore.Check(id)
}

func (s Store) ReadStream(key string) (io.ReadCloser, error) {
	key, err := s.ResolveKey(key)
	if err != nil {
		return nil, fmt.Errorf("error resolving key: %v", err)
	}
	keyLock, err := lock.SharedKeyLock(s.imageLockDir, key)
	if err != nil {
		return nil, fmt.Errorf("error locking image: %v", err)
	}
	defer keyLock.Close()

	return s.stores[blobType].ReadStream(key, false)
}

// GetImageManifestJSON gets the ImageManifest JSON bytes with the
// specified key.
func (s *Store) GetImageManifestJSON(key string) ([]byte, error) {
	key, err := s.ResolveKey(key)
	if err != nil {
		return nil, errwrap.Wrap(errors.New("error resolving image ID"), err)
	}
	keyLock, err := lock.SharedKeyLock(s.imageLockDir, key)
	if err != nil {
		return nil, errwrap.Wrap(errors.New("error locking image"), err)
	}
	defer keyLock.Close()

	imj, err := s.stores[imageManifestType].Read(key)
	if err != nil {
		return nil, errwrap.Wrap(errors.New("error retrieving image manifest"), err)
	}
	return imj, nil
}

// GetImageManifestJSON gets the ImageManifest JSON bytes with the
// specified key.
func (s Store) GetImageManifestJSON(key string) ([]byte, error) {
	key, err := s.ResolveKey(key)
	if err != nil {
		return nil, fmt.Errorf("error resolving image ID: %v", err)
	}
	keyLock, err := lock.SharedKeyLock(s.imageLockDir, key)
	if err != nil {
		return nil, fmt.Errorf("error locking image: %v", err)
	}
	defer keyLock.Close()

	imj, err := s.stores[imageManifestType].Read(key)
	if err != nil {
		return nil, fmt.Errorf("error retrieving image manifest: %v", err)
	}
	return imj, nil
}

// Get the ImageManifest with the specified key.
func (s Store) GetImageManifest(key string) (*schema.ImageManifest, error) {
	key, err := s.ResolveKey(key)
	if err != nil {
		return nil, fmt.Errorf("error resolving key: %v", err)
	}
	keyLock, err := lock.SharedKeyLock(s.imageLockDir, key)
	if err != nil {
		return nil, fmt.Errorf("error locking image: %v", err)
	}
	defer keyLock.Close()

	imj, err := s.stores[imageManifestType].Read(key)
	if err != nil {
		return nil, fmt.Errorf("error retrieving image manifest: %v", err)
	}
	var im *schema.ImageManifest
	if err = json.Unmarshal(imj, &im); err != nil {
		return nil, fmt.Errorf("error unmarshalling image manifest: %v", err)
	}
	return im, nil
}

//.........这里部分代码省略.........
			stderr.PrintE("error saving pod UUID to file", err)
			return 1
		}
	}

	processLabel, mountLabel, err := label.InitLabels([]string{"mcsdir:/var/run/rkt/mcs"})
	if err != nil {
		stderr.PrintE("error initialising SELinux", err)
		return 1
	}

	p.mountLabel = mountLabel

	cfg := stage0.CommonConfig{
		MountLabel:   mountLabel,
		ProcessLabel: processLabel,
		Store:        s,
		TreeStore:    ts,
		Stage1Image:  *s1img,
		UUID:         p.uuid,
		Debug:        globalFlags.Debug,
	}

	pcfg := stage0.PrepareConfig{
		CommonConfig:       &cfg,
		UseOverlay:         !flagNoOverlay && common.SupportsOverlay() && common.FSSupportsOverlay(getDataDir()),
		PrivateUsers:       privateUsers,
		SkipTreeStoreCheck: globalFlags.InsecureFlags.SkipOnDiskCheck(),
	}

	if len(flagPodManifest) > 0 {
		pcfg.PodManifest = flagPodManifest
	} else {
		pcfg.Ports = []types.ExposedPort(flagPorts)
		pcfg.InheritEnv = flagInheritEnv
		pcfg.ExplicitEnv = flagExplicitEnv.Strings()
		pcfg.EnvFromFile = flagEnvFromFile.Strings()
		pcfg.Apps = &rktApps
	}

	if globalFlags.Debug {
		stage0.InitDebug()
	}

	keyLock, err := lock.SharedKeyLock(lockDir(), common.PrepareLock)
	if err != nil {
		stderr.PrintE("cannot get shared prepare lock", err)
		return 1
	}
	err = stage0.Prepare(pcfg, p.path(), p.uuid)
	if err != nil {
		stderr.PrintE("error setting up stage0", err)
		keyLock.Close()
		return 1
	}
	keyLock.Close()

	// get the lock fd for run
	lfd, err := p.Fd()
	if err != nil {
		stderr.PrintE("error getting pod lock fd", err)
		return 1
	}

	// skip prepared by jumping directly to run, we own this pod
	if err := p.xToRun(); err != nil {
		stderr.PrintE("unable to transition to run", err)
		return 1
	}

	rktgid, err := common.LookupGid(common.RktGroup)
	if err != nil {
		stderr.Printf("group %q not found, will use default gid when rendering images", common.RktGroup)
		rktgid = -1
	}

	rcfg := stage0.RunConfig{
		CommonConfig: &cfg,
		Net:          flagNet,
		LockFd:       lfd,
		Interactive:  flagInteractive,
		DNS:          flagDNS,
		DNSSearch:    flagDNSSearch,
		DNSOpt:       flagDNSOpt,
		MDSRegister:  flagMDSRegister,
		LocalConfig:  globalFlags.LocalConfigDir,
		RktGid:       rktgid,
		Hostname:     flagHostname,
	}

	apps, err := p.getApps()
	if err != nil {
		stderr.PrintE("cannot get the appList in the pod manifest", err)
		return 1
	}
	rcfg.Apps = apps
	stage0.Run(rcfg, p.path(), getDataDir()) // execs, never returns

	return 1
}

//.........这里部分代码省略.........
	if err != nil {
		stderr("Error creating new pod: %v", err)
		return 1
	}

	// if requested, write out pod UUID early so "rkt rm" can
	// clean it up even if something goes wrong
	if flagUUIDFileSave != "" {
		if err := writeUUIDToFile(p.uuid, flagUUIDFileSave); err != nil {
			stderr("Error saving pod UUID to file: %v", err)
			return 1
		}
	}

	processLabel, mountLabel, err := label.InitLabels(nil)
	if err != nil {
		stderr("Error initialising SELinux: %v", err)
		return 1
	}

	cfg := stage0.CommonConfig{
		MountLabel:   mountLabel,
		ProcessLabel: processLabel,
		Store:        s,
		Stage1Image:  *s1img,
		UUID:         p.uuid,
		Debug:        globalFlags.Debug,
	}

	pcfg := stage0.PrepareConfig{
		CommonConfig: cfg,
		UseOverlay:   !flagNoOverlay && common.SupportsOverlay(),
		PrivateUsers: privateUsers,
	}

	if len(flagPodManifest) > 0 {
		pcfg.PodManifest = flagPodManifest
	} else {
		pcfg.Ports = []types.ExposedPort(flagPorts)
		pcfg.InheritEnv = flagInheritEnv
		pcfg.ExplicitEnv = flagExplicitEnv.Strings()
		pcfg.Apps = &rktApps
	}

	if globalFlags.Debug {
		stage0.InitDebug()
	}

	keyLock, err := lock.SharedKeyLock(lockDir(), common.PrepareLock)
	if err != nil {
		stderr("rkt: cannot get shared prepare lock: %v", err)
		return 1
	}
	err = stage0.Prepare(pcfg, p.path(), p.uuid)
	if err != nil {
		stderr("run: error setting up stage0: %v", err)
		keyLock.Close()
		return 1
	}
	keyLock.Close()

	// get the lock fd for run
	lfd, err := p.Fd()
	if err != nil {
		stderr("Error getting pod lock fd: %v", err)
		return 1
	}

	// skip prepared by jumping directly to run, we own this pod
	if err := p.xToRun(); err != nil {
		stderr("run: unable to transition to run: %v", err)
		return 1
	}

	rktgid, err := common.LookupGid(common.RktGroup)
	if err != nil {
		stderr("run: group %q not found, will use default gid when rendering images", common.RktGroup)
		rktgid = -1
	}

	rcfg := stage0.RunConfig{
		CommonConfig: cfg,
		Net:          flagNet,
		LockFd:       lfd,
		Interactive:  flagInteractive,
		MDSRegister:  flagMDSRegister,
		LocalConfig:  globalFlags.LocalConfigDir,
		RktGid:       rktgid,
	}

	apps, err := p.getApps()
	if err != nil {
		stderr("run: cannot get the appList in the pod manifest: %v", err)
		return 1
	}
	rcfg.Apps = apps
	stage0.Run(rcfg, p.path(), globalFlags.Dir) // execs, never returns

	return 1
}

//.........这里部分代码省略.........
	if rktApps.Count() < 1 && len(flagPodManifest) == 0 {
		stderr("prepare: must provide at least one image or specify the pod manifest")
		return 1
	}

	s, err := store.NewStore(getDataDir())
	if err != nil {
		stderr("prepare: cannot open store: %v", err)
		return 1
	}

	config, err := getConfig()
	if err != nil {
		stderr("prepare: cannot get configuration: %v", err)
		return 1
	}

	s1img, err := getStage1Hash(s, cmd)
	if err != nil {
		stderr("prepare: %v", err)
		return 1
	}

	fn := &image.Finder{
		S:                  s,
		Ks:                 getKeystore(),
		Headers:            config.AuthPerHost,
		DockerAuth:         config.DockerCredentialsPerRegistry,
		InsecureFlags:      globalFlags.InsecureFlags,
		Debug:              globalFlags.Debug,
		TrustKeysFromHttps: globalFlags.TrustKeysFromHttps,

		StoreOnly: flagStoreOnly,
		NoStore:   flagNoStore,
		WithDeps:  true,
	}
	if err := fn.FindImages(&rktApps); err != nil {
		stderr("prepare: %v", err)
		return 1
	}

	p, err := newPod()
	if err != nil {
		stderr("prepare: error creating new pod: %v", err)
		return 1
	}

	cfg := stage0.CommonConfig{
		Store:       s,
		Stage1Image: *s1img,
		UUID:        p.uuid,
		Debug:       globalFlags.Debug,
	}

	pcfg := stage0.PrepareConfig{
		CommonConfig: &cfg,
		UseOverlay:   !flagNoOverlay && common.SupportsOverlay(),
		PrivateUsers: privateUsers,
	}

	if len(flagPodManifest) > 0 {
		pcfg.PodManifest = flagPodManifest
	} else {
		pcfg.Ports = []types.ExposedPort(flagPorts)
		pcfg.InheritEnv = flagInheritEnv
		pcfg.ExplicitEnv = flagExplicitEnv.Strings()
		pcfg.Apps = &rktApps
	}

	if globalFlags.Debug {
		stage0.InitDebug()
	}

	keyLock, err := lock.SharedKeyLock(lockDir(), common.PrepareLock)
	if err != nil {
		stderr("rkt: cannot get shared prepare lock: %v", err)
		return 1
	}
	if err = stage0.Prepare(pcfg, p.path(), p.uuid); err != nil {
		stderr("prepare: error setting up stage0: %v", err)
		keyLock.Close()
		return 1
	}
	keyLock.Close()

	if err := p.sync(); err != nil {
		stderr("prepare: error syncing pod data: %v", err)
		return 1
	}

	if err := p.xToPrepared(); err != nil {
		stderr("prepare: error transitioning to prepared: %v", err)
		return 1
	}

	os.Stdout = origStdout // restore output in case of --quiet
	stdout("%s", p.uuid.String())

	return 0
}

func runAppSandbox(cmd *cobra.Command, args []string) int {
	s, err := imagestore.NewStore(storeDir())
	if err != nil {
		stderr.PrintE("cannot open store", err)
		return 1
	}

	ts, err := treestore.NewStore(treeStoreDir(), s)
	if err != nil {
		stderr.PrintE("cannot open treestore", err)
		return 1
	}

	config, err := getConfig()
	if err != nil {
		stderr.PrintE("cannot get configuration", err)
		return 1
	}

	s1img, err := getStage1Hash(s, ts, config)
	if err != nil {
		stderr.Error(err)
		return 1
	}

	p, err := pod.NewPod(getDataDir())
	if err != nil {
		stderr.PrintE("error creating new pod", err)
		return 1
	}

	if flagUUIDFileSave != "" {
		if err := pod.WriteUUIDToFile(p.UUID, flagUUIDFileSave); err != nil {
			stderr.PrintE("error saving pod UUID to file", err)
			return 1
		}
	}

	processLabel, mountLabel, err := label.InitLabels("/var/run/rkt/mcs", []string{})
	if err != nil {
		stderr.PrintE("error initialising SELinux", err)
		return 1
	}

	p.MountLabel = mountLabel
	cfg := stage0.CommonConfig{
		DataDir:      getDataDir(),
		MountLabel:   mountLabel,
		ProcessLabel: processLabel,
		Store:        s,
		TreeStore:    ts,
		Stage1Image:  *s1img,
		UUID:         p.UUID,
		Debug:        globalFlags.Debug,
		Mutable:      true,
	}

	ovlOk := true
	if err := common.PathSupportsOverlay(getDataDir()); err != nil {
		if oerr, ok := err.(common.ErrOverlayUnsupported); ok {
			stderr.Printf("disabling overlay support: %q", oerr.Error())
			ovlOk = false
		} else {
			stderr.PrintE("error determining overlay support", err)
			return 1
		}
	}

	useOverlay := !flagNoOverlay && ovlOk

	pcfg := stage0.PrepareConfig{
		CommonConfig:       &cfg,
		UseOverlay:         useOverlay,
		PrivateUsers:       user.NewBlankUidRange(),
		SkipTreeStoreCheck: globalFlags.InsecureFlags.SkipOnDiskCheck(),
		Apps:               &rktApps,
		Ports:              []types.ExposedPort(flagAppPorts),
		UserAnnotations:    parseAnnotations(&flagAnnotations),
		UserLabels:         parseLabels(&flagLabels),
	}

	if globalFlags.Debug {
		stage0.InitDebug()
	}

	keyLock, err := lock.SharedKeyLock(lockDir(), common.PrepareLock)
	if err != nil {
		stderr.PrintE("cannot get shared prepare lock", err)
		return 1
	}

	err = stage0.Prepare(pcfg, p.Path(), p.UUID)
	if err != nil {
		stderr.PrintE("error setting up stage0", err)
		keyLock.Close()
		return 1
	}
	keyLock.Close()

	// get the lock fd for run
//.........这里部分代码省略.........

//.........这里部分代码省略.........

	s1img, err := getStage1Hash(s, ts, config)
	if err != nil {
		stderr.Error(err)
		return 254
	}

	fn := &image.Finder{
		S:                  s,
		Ts:                 ts,
		Ks:                 getKeystore(),
		Headers:            config.AuthPerHost,
		DockerAuth:         config.DockerCredentialsPerRegistry,
		InsecureFlags:      globalFlags.InsecureFlags,
		Debug:              globalFlags.Debug,
		TrustKeysFromHTTPS: globalFlags.TrustKeysFromHTTPS,

		StoreOnly: flagStoreOnly,
		NoStore:   flagNoStore,
		WithDeps:  true,
	}
	if err := fn.FindImages(&rktApps); err != nil {
		stderr.PrintE("error finding images", err)
		return 254
	}

	p, err := pkgPod.NewPod(getDataDir())
	if err != nil {
		stderr.PrintE("error creating new pod", err)
		return 254
	}

	cfg := stage0.CommonConfig{
		DataDir:     getDataDir(),
		Store:       s,
		TreeStore:   ts,
		Stage1Image: *s1img,
		UUID:        p.UUID,
		Debug:       globalFlags.Debug,
	}

	ovlOk := true
	if err := common.PathSupportsOverlay(getDataDir()); err != nil {
		if oerr, ok := err.(common.ErrOverlayUnsupported); ok {
			stderr.Printf("disabling overlay support: %q", oerr.Error())
			ovlOk = false
		} else {
			stderr.PrintE("error determining overlay support", err)
			return 254
		}
	}

	pcfg := stage0.PrepareConfig{
		CommonConfig:       &cfg,
		UseOverlay:         !flagNoOverlay && ovlOk,
		PrivateUsers:       privateUsers,
		SkipTreeStoreCheck: globalFlags.InsecureFlags.SkipOnDiskCheck(),
	}

	if len(flagPodManifest) > 0 {
		pcfg.PodManifest = flagPodManifest
	} else {
		pcfg.Ports = []types.ExposedPort(flagPorts)
		pcfg.InheritEnv = flagInheritEnv
		pcfg.ExplicitEnv = flagExplicitEnv.Strings()
		pcfg.EnvFromFile = flagEnvFromFile.Strings()
		pcfg.Apps = &rktApps
	}

	if globalFlags.Debug {
		stage0.InitDebug()
	}

	keyLock, err := lock.SharedKeyLock(lockDir(), common.PrepareLock)
	if err != nil {
		stderr.PrintE("cannot get shared prepare lock", err)
		return 254
	}
	if err = stage0.Prepare(pcfg, p.Path(), p.UUID); err != nil {
		stderr.PrintE("error setting up stage0", err)
		keyLock.Close()
		return 254
	}
	keyLock.Close()

	if err := p.Sync(); err != nil {
		stderr.PrintE("error syncing pod data", err)
		return 254
	}

	if err := p.ToPrepared(); err != nil {
		stderr.PrintE("error transitioning to prepared", err)
		return 254
	}

	os.Stdout = origStdout // restore output in case of --quiet
	stdout.Printf("%s", p.UUID.String())

	return 0
}