Add Get of task and process state

Signed-off-by: Michael Crosby <crosbymichael@gmail.com>

linux/shim/exec.go

@@ -27,6 +27,7 @@ import (
 type execProcess struct {
 	sync.WaitGroup
 
+	mu      sync.Mutex
 	id      string
 	console console.Console
 	io      runc.IO
@@ -73,6 +74,8 @@ func (e *execProcess) ID() string {
 }
 
 func (e *execProcess) Pid() int {
+	e.mu.Lock()
+	defer e.mu.Unlock()
 	return e.pid
 }
 
@@ -109,8 +112,13 @@ func (e *execProcess) Resize(ws console.WinSize) error {
 }
 
 func (e *execProcess) Kill(ctx context.Context, sig uint32, _ bool) error {
-	if err := unix.Kill(e.pid, syscall.Signal(sig)); err != nil {
-		return errors.Wrapf(checkKillError(err), "exec kill error")
+	e.mu.Lock()
+	pid := e.pid
+	e.mu.Unlock()
+	if pid != 0 {
+		if err := unix.Kill(pid, syscall.Signal(sig)); err != nil {
+			return errors.Wrapf(checkKillError(err), "exec kill error")
+		}
 	}
 	return nil
 }
@@ -179,6 +187,33 @@ func (e *execProcess) Start(ctx context.Context) (err error) {
 	if err != nil {
 		return errors.Wrap(err, "failed to retrieve OCI runtime exec pid")
 	}
+	e.mu.Lock()
 	e.pid = pid
+	e.mu.Unlock()
 	return nil
 }
+
+func (e *execProcess) Status(ctx context.Context) (string, error) {
+	s, err := e.parent.Status(ctx)
+	if err != nil {
+		return "", err
+	}
+	// if the container as a whole is in the pausing/paused state, so are all
+	// other processes inside the container, use container state here
+	switch s {
+	case "paused", "pausing":
+		return s, nil
+	}
+	e.mu.Lock()
+	defer e.mu.Unlock()
+	// if we don't have a pid then the exec process has just been created
+	if e.pid == 0 {
+		return "created", nil
+	}
+	// if we have a pid and it can be signaled, the process is running
+	if err := unix.Kill(e.pid, 0); err == nil {
+		return "running", nil
+	}
+	// else if we have a pid but it can nolonger be signaled, it has stopped
+	return "stopped", nil
+}

linux/shim/init.go

@@ -209,8 +209,8 @@ func (p *initProcess) ExitedAt() time.Time {
 	return p.exited
 }
 
-// ContainerStatus return the state of the container (created, running, paused, stopped)
-func (p *initProcess) ContainerStatus(ctx context.Context) (string, error) {
+// Status return the state of the container (created, running, paused, stopped)
+func (p *initProcess) Status(ctx context.Context) (string, error) {
 	c, err := p.runtime.State(ctx, p.id)
 	if err != nil {
 		return "", p.runtimeError(err, "OCI runtime state failed")
@@ -233,7 +233,7 @@ func (p *initProcess) SetExited(status int) {
 }
 
 func (p *initProcess) Delete(context context.Context) error {
-	status, err := p.ContainerStatus(context)
+	status, err := p.Status(context)
 	if err != nil {
 		return err
 	}

linux/shim/process.go

@@ -40,4 +40,6 @@ type process interface {
 	Stdio() stdio
 	// Start execution of the process
 	Start(context.Context) error
+	// Status returns the process status
+	Status(ctx context.Context) (string, error)
 }

linux/shim/service.go

@@ -229,14 +229,11 @@ func (s *Service) ResizePty(ctx context.Context, r *shimapi.ResizePtyRequest) (*
 }
 
 func (s *Service) State(ctx context.Context, r *shimapi.StateRequest) (*shimapi.StateResponse, error) {
-	if s.initProcess == nil {
-		return nil, errdefs.ToGRPCf(errdefs.ErrFailedPrecondition, "container must be created")
-	}
 	p, ok := s.processes[r.ID]
 	if !ok {
 		return nil, errdefs.ToGRPCf(errdefs.ErrNotFound, "process id %s not found", r.ID)
 	}
-	st, err := s.initProcess.ContainerStatus(ctx)
+	st, err := p.Status(ctx)
 	if err != nil {
 		return nil, err
 	}

linux/task.go

@@ -66,7 +66,6 @@ func (t *Task) State(ctx context.Context) (runtime.State, error) {
 		status = runtime.StoppedStatus
 	case task.StatusPaused:
 		status = runtime.PausedStatus
-		// TODO: containerd.DeletedStatus
 	}
 	return runtime.State{
 		Pid:      response.Pid,