execution: remove statedir type

Signed-off-by: Kenfe-Mickael Laventure <mickael.laventure@gmail.com>

execution/container.go

@@ -1,91 +1,179 @@
 package execution
 
-import "fmt"
+import (
+	"context"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"sync"
 
-func NewContainer(stateRoot, id, bundle string) (*Container, error) {
+	"github.com/docker/containerd/log"
-	stateDir, err := NewStateDir(stateRoot, id)
+	"github.com/pkg/errors"
-	if err != nil {
+)
-		return nil, err
+
-	}
+const (
-	return &Container{
+	InitProcessID    = "init"
+	processesDirName = "processes"
+	bundleFileName   = "bundle"
+)
+
+func LoadContainer(ctx context.Context, stateDir, id string) (c *Container, err error) {
+	c = &Container{
 		id:        id,
-		bundle:    bundle,
 		stateDir:  stateDir,
-		status:    Created,
+		processes: make(map[string]Process, 1),
-		processes: make(map[string]Process),
+		ctx:       ctx,
-	}, nil
+		status:    Unknown,
+	}
+
+	data, err := ioutil.ReadFile(filepath.Join(stateDir, bundleFileName))
+	if err != nil {
+		err = errors.Wrapf(err, "failed to read bundle path")
+		return
+	}
+	c.bundle = string(data)
+
+	return
 }
 
-func LoadContainer(dir StateDir, id, bundle string, status Status) *Container {
+func NewContainer(ctx context.Context, stateDir, id, bundle string) (c *Container, err error) {
-	return &Container{
+	c = &Container{
 		id:        id,
-		stateDir:  dir,
+		stateDir:  stateDir,
 		bundle:    bundle,
-		status:    status,
+		processes: make(map[string]Process, 1),
-		processes: make(map[string]Process),
+		status:    Created,
+		ctx:       ctx,
 	}
+	defer func() {
+		if err != nil {
+			c.Cleanup()
+			c = nil
+		}
+	}()
+
+	if err = os.Mkdir(stateDir, 0700); err != nil {
+		err = errors.Wrap(err, "failed to create container state dir")
+		return
+	}
+
+	bundleFile := filepath.Join(stateDir, bundleFileName)
+	if err = ioutil.WriteFile(bundleFile, []byte(bundle), 0600); err != nil {
+		err = errors.Wrap(err, "failed to store bundle path")
+		return
+	}
+
+	processesDir := filepath.Join(stateDir, processesDirName)
+	if err = os.Mkdir(processesDir, 0700); err != nil {
+		err = errors.Wrap(err, "failed to create processes statedir")
+		return
+	}
+
+	return
 }
 
 type Container struct {
-	id       string
+	id        string
-	bundle   string
+	stateDir  string
-	stateDir StateDir
+	bundle    string
-	initPid  int64
-	status   Status
-
 	processes map[string]Process
+	status    Status
+
+	ctx context.Context
+	mu  sync.Mutex
 }
 
 func (c *Container) ID() string {
 	return c.id
 }
 
-func (c *Container) Status() Status {
-	for _, p := range c.processes {
-		if p.Pid() == c.initPid {
-			c.status = p.Status()
-			break
-		}
-	}
-	return c.status
-}
-
 func (c *Container) Bundle() string {
 	return c.bundle
 }
 
-func (c *Container) StateDir() StateDir {
-	return c.stateDir
-}
-
 func (c *Container) Wait() (uint32, error) {
-	for _, p := range c.processes {
+	initProcess := c.GetProcess(InitProcessID)
-		if p.Pid() == c.initPid {
+	return initProcess.Wait()
-			return p.Wait()
-		}
-	}
-	return 0, fmt.Errorf("no init process")
 }
 
-func (c *Container) AddProcess(p Process, isInit bool) {
+func (c *Container) Status() Status {
-	if isInit {
+	initProcess := c.GetProcess(InitProcessID)
-		c.initPid = p.Pid()
+	return initProcess.Status()
-	}
+}
+
+func (c *Container) AddProcess(p Process) {
+	c.mu.Lock()
 	c.processes[p.ID()] = p
+	c.mu.Unlock()
+}
+
+func (c *Container) RemoveProcess(id string) error {
+	if _, ok := c.processes[id]; !ok {
+		return errors.Errorf("no such process %s", id)
+	}
+
+	c.mu.Lock()
+	delete(c.processes, id)
+	c.mu.Unlock()
+
+	processStateDir := filepath.Join(c.stateDir, processesDirName, id)
+	err := os.RemoveAll(processStateDir)
+	if err != nil {
+		return errors.Wrap(err, "failed to remove process state dir")
+	}
+
+	return nil
 }
 
 func (c *Container) GetProcess(id string) Process {
+	c.mu.Lock()
+	defer c.mu.Unlock()
 	return c.processes[id]
 }
 
-func (c *Container) RemoveProcess(id string) {
+func (c *Container) Processes() []Process {
-	delete(c.processes, id)
+	var procs []Process
+
+	c.mu.Lock()
+	for _, p := range c.processes {
+		procs = append(procs, p)
+	}
+	c.mu.Unlock()
+
+	return procs
 }
 
-func (c *Container) Processes() []Process {
+// ProcessStateDir returns the path of the state dir for a given
-	var out []Process
+// process id. The process doesn't have to exist for this to succeed.
-	for _, p := range c.processes {
+func (c *Container) ProcessStateDir(id string) string {
-		out = append(out, p)
+	return filepath.Join(c.stateDir, processesDirName, id)
-	}
+}
-	return out
+
+// ProcessesStateDir returns a map matching process ids to their state
+// directory
+func (c *Container) ProcessesStateDir() (map[string]string, error) {
+	root := filepath.Join(c.stateDir, processesDirName)
+	dirs, err := ioutil.ReadDir(root)
+	if err != nil {
+		return nil, errors.Wrapf(err, "failed to list processes state dirs")
+	}
+
+	procs := make(map[string]string, 1)
+	for _, d := range dirs {
+		if d.IsDir() {
+			procs[d.Name()] = filepath.Join(root, d.Name())
+		}
+	}
+
+	return procs, nil
+}
+
+func (c *Container) Cleanup() {
+	if err := os.RemoveAll(c.stateDir); err != nil {
+		log.G(c.ctx).Warnf("failed to remove container state dir: %v", err)
+	}
+}
+
+func (c *Container) Context() context.Context {
+	return c.ctx
 }

execution/executors/shim/process.go

@@ -27,34 +27,37 @@ type newProcessOpts struct {
 	runtimeArgs []string
 	container   *execution.Container
 	exec        bool
+	stateDir    string
 	execution.StartProcessOpts
 }
 
-func newProcess(ctx context.Context, o newProcessOpts) (*process, error) {
+func newProcess(ctx context.Context, o newProcessOpts) (p *process, err error) {
-	procStateDir, err := o.container.StateDir().NewProcess(o.ID)
+	p = &process{
-	if err != nil {
+		id:       o.ID,
-		return nil, err
+		stateDir: o.stateDir,
+		exitChan: make(chan struct{}),
+		ctx:      ctx,
 	}
 	defer func() {
 		if err != nil {
-			o.container.StateDir().DeleteProcess(o.ID)
+			p.cleanup()
+			p = nil
 		}
 	}()
 
-	exitPipe, controlPipe, err := getControlPipes(procStateDir)
+	if err = os.Mkdir(o.stateDir, 0700); err != nil {
-	if err != nil {
+		err = errors.Wrap(err, "failed to create process state dir")
-		return nil, err
+		return
 	}
-	defer func() {
-		if err != nil {
-			exitPipe.Close()
-			controlPipe.Close()
-		}
-	}()
 
-	cmd, err := newShim(o, procStateDir)
+	p.exitPipe, p.controlPipe, err = getControlPipes(o.stateDir)
 	if err != nil {
-		return nil, err
+		return
+	}
+
+	cmd, err := newShimProcess(o)
+	if err != nil {
+		return
 	}
 	defer func() {
 		if err != nil {
@@ -75,70 +78,52 @@ func newProcess(ctx context.Context, o newProcessOpts) (*process, error) {
 		close(abortCh)
 	}()
 
-	process := &process{
+	p.pid, p.startTime, p.status, err = waitUntilReady(ctx, abortCh, o.stateDir)
-		root:        procStateDir,
-		id:          o.ID,
-		exitChan:    make(chan struct{}),
-		exitPipe:    exitPipe,
-		controlPipe: controlPipe,
-	}
-
-	pid, stime, status, err := waitForPid(ctx, abortCh, procStateDir)
 	if err != nil {
-		return nil, err
+		return
 	}
-	process.pid = int64(pid)
-	process.status = status
-	process.startTime = stime
 
-	return process, nil
+	return
 }
 
-func loadProcess(root, id string) (*process, error) {
+func loadProcess(ctx context.Context, stateDir, id string) (p *process, err error) {
-	pid, err := runc.ReadPidFile(filepath.Join(root, pidFilename))
+	p = &process{
-	if err != nil {
+		id:       id,
-		return nil, err
+		stateDir: stateDir,
-	}
+		exitChan: make(chan struct{}),
-
+		status:   execution.Running,
-	stime, err := ioutil.ReadFile(filepath.Join(root, startTimeFilename))
+		ctx:      ctx,
-	if err != nil {
-		return nil, err
-	}
-
-	path := filepath.Join(root, exitPipeFilename)
-	exitPipe, err := os.OpenFile(path, syscall.O_RDONLY|syscall.O_NONBLOCK, 0)
-	if err != nil {
-		return nil, err
 	}
 	defer func() {
 		if err != nil {
-			exitPipe.Close()
+			p.cleanup()
+			p = nil
 		}
 	}()
 
-	path = filepath.Join(root, controlPipeFilename)
+	p.pid, err = getPidFromFile(filepath.Join(stateDir, pidFilename))
-	controlPipe, err := os.OpenFile(path, syscall.O_RDWR|syscall.O_NONBLOCK, 0)
 	if err != nil {
-		return nil, err
+		err = errors.Wrap(err, "failed to read pid")
+		return
 	}
-	defer func() {
-		if err != nil {
-			controlPipe.Close()
-		}
-	}()
 
-	p := &process{
+	p.startTime, err = getStartTimeFromFile(filepath.Join(stateDir, startTimeFilename))
-		root:        root,
+	if err != nil {
-		id:          id,
+		return
-		pid:         int64(pid),
+	}
-		exitChan:    make(chan struct{}),
+
-		exitPipe:    exitPipe,
+	path := filepath.Join(stateDir, exitPipeFilename)
-		controlPipe: controlPipe,
+	p.exitPipe, err = os.OpenFile(path, syscall.O_RDONLY|syscall.O_NONBLOCK, 0)
-		startTime:   string(stime),
+	if err != nil {
-		// TODO: status may need to be stored on disk to handle
+		err = errors.Wrapf(err, "failed to open exit pipe")
-		// Created state for init (i.e. a Start is needed to run the
+		return
-		// container)
+	}
-		status: execution.Running,
+
+	path = filepath.Join(stateDir, controlPipeFilename)
+	p.controlPipe, err = os.OpenFile(path, syscall.O_RDWR|syscall.O_NONBLOCK, 0)
+	if err != nil {
+		err = errors.Wrapf(err, "failed to open control pipe")
+		return
 	}
 
 	markAsStopped := func(p *process) (*process, error) {
@@ -146,30 +131,32 @@ func loadProcess(root, id string) (*process, error) {
 		return p, nil
 	}
 
-	if err = syscall.Kill(pid, 0); err != nil {
+	if err = syscall.Kill(int(p.pid), 0); err != nil {
 		if err == syscall.ESRCH {
 			return markAsStopped(p)
 		}
-		return nil, err
+		err = errors.Wrapf(err, "failed to check if process is still alive")
+		return
 	}
 
-	cstime, err := starttime.GetProcessStartTime(pid)
+	cstime, err := starttime.GetProcessStartTime(int(p.pid))
 	if err != nil {
 		if os.IsNotExist(err) {
 			return markAsStopped(p)
 		}
-		return nil, err
+		err = errors.Wrapf(err, "failed retrieve current process start time")
+		return
 	}
 
 	if p.startTime != cstime {
 		return markAsStopped(p)
 	}
 
-	return p, nil
+	return
 }
 
 type process struct {
-	root        string
+	stateDir    string
 	id          string
 	pid         int64
 	exitChan    chan struct{}
@@ -211,7 +198,7 @@ func (p *process) Wait() (uint32, error) {
 		return uint32(128 + int(syscall.SIGKILL)), nil
 	}
 
-	data, err := ioutil.ReadFile(filepath.Join(p.root, exitStatusFilename))
+	data, err := ioutil.ReadFile(filepath.Join(p.stateDir, exitStatusFilename))
 	if err != nil {
 		return execution.UnknownStatusCode, errors.Wrap(err, "failed to read process exit status")
 	}
@@ -278,7 +265,19 @@ func (p *process) isAlive() bool {
 	return true
 }
 
-func waitForPid(ctx context.Context, abortCh chan syscall.WaitStatus, root string) (pid int, stime string, status execution.Status, err error) {
+func (p *process) cleanup() {
+	for _, f := range []*os.File{p.exitPipe, p.controlPipe} {
+		if f != nil {
+			f.Close()
+		}
+	}
+
+	if err := os.RemoveAll(p.stateDir); err != nil {
+		log.G(p.ctx).Warnf("failed to remove process state dir: %v", err)
+	}
+}
+
+func waitUntilReady(ctx context.Context, abortCh chan syscall.WaitStatus, root string) (pid int64, stime string, status execution.Status, err error) {
 	status = execution.Unknown
 	for {
 		select {
@@ -293,7 +292,7 @@ func waitForPid(ctx context.Context, abortCh chan syscall.WaitStatus, root strin
 			return
 		default:
 		}
-		pid, err = runc.ReadPidFile(filepath.Join(root, pidFilename))
+		pid, err = getPidFromFile(filepath.Join(root, pidFilename))
 		if err == nil {
 			break
 		} else if !os.IsNotExist(err) {
@@ -301,7 +300,7 @@ func waitForPid(ctx context.Context, abortCh chan syscall.WaitStatus, root strin
 		}
 	}
 	status = execution.Created
-	stime, err = starttime.GetProcessStartTime(pid)
+	stime, err = starttime.GetProcessStartTime(int(pid))
 	switch {
 	case os.IsNotExist(err):
 		status = execution.Stopped
@@ -328,9 +327,9 @@ func waitForPid(ctx context.Context, abortCh chan syscall.WaitStatus, root strin
 	return pid, stime, status, nil
 }
 
-func newShim(o newProcessOpts, workDir string) (*exec.Cmd, error) {
+func newShimProcess(o newProcessOpts) (*exec.Cmd, error) {
 	cmd := exec.Command(o.shimBinary, o.container.ID(), o.container.Bundle(), o.runtime)
-	cmd.Dir = workDir
+	cmd.Dir = o.stateDir
 	cmd.SysProcAttr = &syscall.SysProcAttr{
 		Setpgid: true,
 	}
@@ -348,12 +347,11 @@ func newShim(o newProcessOpts, workDir string) (*exec.Cmd, error) {
 		RootGID:        int(o.Spec.User.GID),
 	}
 
-	f, err := os.Create(filepath.Join(workDir, "process.json"))
+	f, err := os.Create(filepath.Join(o.stateDir, "process.json"))
 	if err != nil {
 		return nil, errors.Wrapf(err, "failed to create shim's process.json for container %s", o.container.ID())
 	}
 	defer f.Close()
-
 	if err := json.NewEncoder(f).Encode(state); err != nil {
 		return nil, errors.Wrapf(err, "failed to create shim's processState for container %s", o.container.ID())
 	}
@@ -368,19 +366,39 @@ func newShim(o newProcessOpts, workDir string) (*exec.Cmd, error) {
 func getControlPipes(root string) (exitPipe *os.File, controlPipe *os.File, err error) {
 	path := filepath.Join(root, exitPipeFilename)
 	if err = unix.Mkfifo(path, 0700); err != nil {
-		return exitPipe, controlPipe, errors.Wrap(err, "failed to create shim exit fifo")
+		err = errors.Wrap(err, "failed to create shim exit fifo")
+		return
 	}
 	if exitPipe, err = os.OpenFile(path, syscall.O_RDONLY|syscall.O_NONBLOCK, 0); err != nil {
-		return exitPipe, controlPipe, errors.Wrap(err, "failed to open shim exit fifo")
+		err = errors.Wrap(err, "failed to open shim exit fifo")
+		return
 	}
 
 	path = filepath.Join(root, controlPipeFilename)
 	if err = unix.Mkfifo(path, 0700); err != nil {
-		return exitPipe, controlPipe, errors.Wrap(err, "failed to create shim control fifo")
+		err = errors.Wrap(err, "failed to create shim control fifo")
+		return
 	}
 	if controlPipe, err = os.OpenFile(path, syscall.O_RDWR|syscall.O_NONBLOCK, 0); err != nil {
-		return exitPipe, controlPipe, errors.Wrap(err, "failed to open shim control fifo")
+		err = errors.Wrap(err, "failed to open shim control fifo")
+		return
 	}
 
-	return exitPipe, controlPipe, nil
+	return
+}
+
+func getPidFromFile(path string) (int64, error) {
+	pid, err := runc.ReadPidFile(path)
+	if err != nil {
+		return -1, err
+	}
+	return int64(pid), nil
+}
+
+func getStartTimeFromFile(path string) (string, error) {
+	stime, err := ioutil.ReadFile(path)
+	if err != nil {
+		return "", errors.Wrapf(err, "failed to read start time")
+	}
+	return string(stime), nil
 }

execution/executors/shim/shim.go

@@ -1,6 +1,7 @@
 package shim
 
 import (
+	"bytes"
 	"context"
 	"encoding/json"
 	"io/ioutil"
@@ -24,7 +25,6 @@ const (
 	startTimeFilename   = "starttime"
 	exitPipeFilename    = "exit"
 	controlPipeFilename = "control"
-	initProcessID       = "init"
 	exitStatusFilename  = "exitStatus"
 )
 
@@ -93,21 +93,17 @@ func (s *ShimRuntime) Create(ctx context.Context, id string, o execution.CreateO
 		return nil, execution.ErrContainerExists
 	}
 
-	container, err := execution.NewContainer(s.root, id, o.Bundle)
+	containerCtx := log.WithModule(log.WithModule(ctx, "container"), id)
+	container, err := execution.NewContainer(containerCtx, filepath.Join(s.root, id), id, o.Bundle)
 	if err != nil {
 		return nil, err
 	}
 	defer func() {
 		if err != nil {
-			container.StateDir().Delete()
+			container.Cleanup()
 		}
 	}()
 
-	err = ioutil.WriteFile(filepath.Join(string(container.StateDir()), "bundle"), []byte(o.Bundle), 0600)
-	if err != nil {
-		return nil, errors.Wrap(err, "failed to save bundle path to disk")
-	}
-
 	// extract Process spec from bundle's config.json
 	var spec specs.Spec
 	f, err := os.Open(filepath.Join(o.Bundle, "config.json"))
@@ -125,8 +121,9 @@ func (s *ShimRuntime) Create(ctx context.Context, id string, o execution.CreateO
 		runtimeArgs: s.runtimeArgs,
 		container:   container,
 		exec:        false,
+		stateDir:    container.ProcessStateDir(execution.InitProcessID),
 		StartProcessOpts: execution.StartProcessOpts{
-			ID:      initProcessID,
+			ID:      execution.InitProcessID,
 			Spec:    spec.Process,
 			Console: o.Console,
 			Stdin:   o.Stdin,
@@ -135,14 +132,14 @@ func (s *ShimRuntime) Create(ctx context.Context, id string, o execution.CreateO
 		},
 	}
 
-	process, err := newProcess(ctx, processOpts)
+	processCtx := log.WithModule(log.WithModule(containerCtx, "process"), execution.InitProcessID)
+	process, err := newProcess(processCtx, processOpts)
 	if err != nil {
 		return nil, err
 	}
-	process.ctx = log.WithModule(log.WithModule(s.ctx, "container"), id)
 
 	s.monitorProcess(process)
-	container.AddProcess(process, true)
+	container.AddProcess(process)
 
 	s.addContainer(container)
 
@@ -194,7 +191,7 @@ func (s *ShimRuntime) Delete(ctx context.Context, c *execution.Container) error
 		return errors.Errorf("cannot delete a container in the '%s' state", c.Status())
 	}
 
-	c.StateDir().Delete()
+	c.Cleanup()
 	s.removeContainer(c)
 	return nil
 }
@@ -232,7 +229,9 @@ func (s *ShimRuntime) StartProcess(ctx context.Context, c *execution.Container,
 		exec:             true,
 		StartProcessOpts: o,
 	}
-	process, err := newProcess(ctx, processOpts)
+
+	processCtx := log.WithModule(log.WithModule(c.Context(), "process"), execution.InitProcessID)
+	process, err := newProcess(processCtx, processOpts)
 	if err != nil {
 		return nil, err
 	}
@@ -240,7 +239,7 @@ func (s *ShimRuntime) StartProcess(ctx context.Context, c *execution.Container,
 	process.status = execution.Running
 	s.monitorProcess(process)
 
-	c.AddProcess(process, false)
+	c.AddProcess(process)
 	return process, nil
 }
 
@@ -250,11 +249,11 @@ func (s *ShimRuntime) SignalProcess(ctx context.Context, c *execution.Container,
 
 	process := c.GetProcess(id)
 	if process == nil {
-		return errors.Errorf("no such process %s", id)
+		return errors.Errorf("container %s has no process named %s", c.ID(), id)
 	}
 	err := syscall.Kill(int(process.Pid()), sig.(syscall.Signal))
 	if err != nil {
-		return errors.Wrapf(err, "failed to send %v signal to process %v", sig, process.Pid())
+		return errors.Wrapf(err, "failed to send %v signal to container %s process %v", sig, c.ID(), process.Pid())
 	}
 	return err
 }
@@ -263,13 +262,14 @@ func (s *ShimRuntime) DeleteProcess(ctx context.Context, c *execution.Container,
 	log.G(s.ctx).WithFields(logrus.Fields{"container": c, "process-id": id}).
 		Debug("DeleteProcess()")
 
-	c.RemoveProcess(id)
+	if p := c.GetProcess(id); p != nil {
-	return c.StateDir().DeleteProcess(id)
+		p.(*process).cleanup()
-}
 
-//
+		return c.RemoveProcess(id)
-//
+	}
-//
+
+	return errors.Errorf("container %s has no process named %s", c.ID(), id)
+}
 
 func (s *ShimRuntime) monitor() {
 	var events [128]syscall.EpollEvent
@@ -375,46 +375,56 @@ func (s *ShimRuntime) loadContainers() {
 			continue
 		}
 
-		stateDir, err := execution.LoadStateDir(s.root, c.Name())
+		stateDir := filepath.Join(s.root, c.Name())
+		containerCtx := log.WithModule(log.WithModule(s.ctx, "container"), c.Name())
+		container, err := execution.LoadContainer(containerCtx, stateDir, c.Name())
 		if err != nil {
-			// We should never fail the above call unless someone
+			log.G(s.ctx).WithField("container-id", c.Name()).Warn(err)
-			// delete the directory while we're loading
-			log.G(s.ctx).WithFields(logrus.Fields{"container": c.Name(), "statedir": s.root}).
-				Warn("failed to load container statedir:", err)
-			continue
-		}
-		bundle, err := ioutil.ReadFile(filepath.Join(string(stateDir), "bundle"))
-		if err != nil {
-			log.G(s.ctx).WithField("container", c.Name()).
-				Warn("failed to load container bundle path:", err)
 			continue
 		}
 
-		container := execution.LoadContainer(stateDir, c.Name(), string(bundle), execution.Unknown)
+		processDirs, err := container.ProcessesStateDir()
-		s.addContainer(container)
-
-		processDirs, err := stateDir.Processes()
 		if err != nil {
-			log.G(s.ctx).WithField("container", c.Name()).
+			log.G(s.ctx).WithField("container-id", c.Name()).Warn(err)
-				Warn("failed to retrieve container processes:", err)
 			continue
 		}
 
-		for _, procStateRoot := range processDirs {
+		for processID, processStateDir := range processDirs {
-			id := filepath.Base(procStateRoot)
+			processCtx := log.WithModule(log.WithModule(containerCtx, "process"), processID)
-			proc, err := loadProcess(procStateRoot, id)
+			var p *process
+			p, err = loadProcess(processCtx, processStateDir, processID)
 			if err != nil {
-				log.G(s.ctx).WithFields(logrus.Fields{"container": c.Name(), "process": id}).
+				log.G(s.ctx).WithFields(logrus.Fields{"container-id": c.Name(), "process": processID}).Warn(err)
-					Warn("failed to load process:", err)
-				s.removeContainer(container)
-				for _, p := range container.Processes() {
-					s.unmonitorProcess(p.(*process))
-				}
 				break
 			}
-			proc.ctx = log.WithModule(log.WithModule(s.ctx, "container"), container.ID())
+			if processID == execution.InitProcessID && p.status == execution.Running {
-			container.AddProcess(proc, proc.ID() == initProcessID)
+				p.status = s.loadContainerStatus(container.ID())
-			s.monitorProcess(proc)
+			}
+			container.AddProcess(p)
+		}
+
+		// if successfull, add the container to our list
+		if err == nil {
+			for _, p := range container.Processes() {
+				s.monitorProcess(p.(*process))
+			}
+			s.addContainer(container)
+			log.G(s.ctx).Infof("restored container %s", container.ID())
 		}
 	}
 }
+
+func (s *ShimRuntime) loadContainerStatus(id string) execution.Status {
+	cmd := exec.Command(s.runtime, append(s.runtimeArgs, "state", id)...)
+	out, err := cmd.CombinedOutput()
+	if err != nil {
+		return execution.Unknown
+	}
+
+	var st struct{ Status string }
+	if err := json.NewDecoder(bytes.NewReader(out)).Decode(&st); err != nil {
+		return execution.Unknown
+	}
+
+	return execution.Status(st.Status)
+}

execution/statedir.go

@@ -1,82 +0,0 @@
-package execution
-
-import (
-	"io/ioutil"
-	"os"
-	"path/filepath"
-
-	"github.com/pkg/errors"
-)
-
-const processesDirName = "processes"
-
-type StateDir string
-
-func LoadStateDir(root, id string) (StateDir, error) {
-	path := filepath.Join(root, id)
-	if _, err := os.Stat(path); err != nil {
-		return "", errors.Wrap(err, "could not find container statedir")
-	}
-	return StateDir(path), nil
-}
-
-func NewStateDir(root, id string) (StateDir, error) {
-	path := filepath.Join(root, id)
-	if err := os.Mkdir(path, 0700); err != nil {
-		return "", errors.Wrap(err, "could not create container statedir")
-	}
-	if err := os.Mkdir(StateDir(path).processesDir(), 0700); err != nil {
-		os.RemoveAll(path)
-		return "", errors.Wrap(err, "could not create processes statedir")
-	}
-	return StateDir(path), nil
-}
-
-func (s StateDir) Delete() error {
-	err := os.RemoveAll(string(s))
-	if err != nil {
-		return errors.Wrapf(err, "failed to remove statedir %s", string(s))
-	}
-	return nil
-}
-
-func (s StateDir) NewProcess(id string) (dir string, err error) {
-	dir = filepath.Join(s.processesDir(), id)
-	if err = os.Mkdir(dir, 0700); err != nil {
-		return "", errors.Wrap(err, "could not create process statedir")
-	}
-
-	return dir, nil
-}
-
-func (s StateDir) ProcessDir(id string) string {
-	return filepath.Join(s.processesDir(), id)
-}
-
-func (s StateDir) DeleteProcess(id string) error {
-	err := os.RemoveAll(filepath.Join(s.processesDir(), id))
-	if err != nil {
-		return errors.Wrapf(err, "failed to remove process %d statedir", id)
-	}
-	return nil
-}
-
-func (s StateDir) Processes() ([]string, error) {
-	procsDir := s.processesDir()
-	dirs, err := ioutil.ReadDir(procsDir)
-	if err != nil {
-		return nil, errors.Wrap(err, "could not list processes statedir")
-	}
-
-	paths := make([]string, 0)
-	for _, d := range dirs {
-		if d.IsDir() {
-			paths = append(paths, filepath.Join(procsDir, d.Name()))
-		}
-	}
-	return paths, nil
-}
-
-func (s StateDir) processesDir() string {
-	return filepath.Join(string(s), processesDirName)
-}

execution/status.go

@@ -5,6 +5,7 @@ type Status string
 const (
 	Created Status = "created"
 	Paused  Status = "paused"
+	Pausing Status = "pausing"
 	Running Status = "running"
 	Stopped Status = "stopped"
 	Deleted Status = "deleted"