Move supervisor to it's own package

It allows to keep main namespace cleaner

Signed-off-by: Alexander Morozov <lk4d4@docker.com>

supervisor/event.go

@@ -0,0 +1,84 @@
+package supervisor
+
+import (
+	"os"
+	"time"
+
+	"github.com/docker/containerd/runtime"
+	"github.com/opencontainers/specs"
+)
+
+type EventType string
+
+const (
+	ExecExitEventType         EventType = "execExit"
+	ExitEventType             EventType = "exit"
+	StartContainerEventType   EventType = "startContainer"
+	DeleteEventType           EventType = "deleteContainerEvent"
+	GetContainerEventType     EventType = "getContainer"
+	SignalEventType           EventType = "signal"
+	AddProcessEventType       EventType = "addProcess"
+	UpdateContainerEventType  EventType = "updateContainer"
+	CreateCheckpointEventType EventType = "createCheckpoint"
+	DeleteCheckpointEventType EventType = "deleteCheckpoint"
+	StatsEventType            EventType = "events"
+	UnsubscribeStatsEventType EventType = "unsubscribeStats"
+	StopStatsEventType        EventType = "stopStats"
+	OOMEventType              EventType = "oom"
+)
+
+func NewEvent(t EventType) *Event {
+	return &Event{
+		Type:      t,
+		Timestamp: time.Now(),
+		Err:       make(chan error, 1),
+	}
+}
+
+type StartResponse struct {
+	Pid int
+}
+
+type Event struct {
+	Type          EventType
+	Timestamp     time.Time
+	ID            string
+	BundlePath    string
+	Stdout        string
+	Stderr        string
+	Stdin         string
+	Console       string
+	Pid           int
+	Status        int
+	Signal        os.Signal
+	Process       *specs.Process
+	State         *runtime.State
+	Containers    []runtime.Container
+	Checkpoint    *runtime.Checkpoint
+	Err           chan error
+	StartResponse chan StartResponse
+	Stats         chan interface{}
+}
+
+type Handler interface {
+	Handle(*Event) error
+}
+
+type commonEvent struct {
+	data *Event
+	sv   *Supervisor
+}
+
+func (e *commonEvent) Handle() {
+	h, ok := e.sv.handlers[e.data.Type]
+	if !ok {
+		e.data.Err <- ErrUnknownEvent
+		return
+	}
+	err := h.Handle(e.data)
+	if err != errDeferedResponse {
+		e.data.Err <- err
+		close(e.data.Err)
+		return
+	}
+}