Refactor runtime code for code sharing

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

pkg/process/process.go

@@ -0,0 +1,56 @@
+/*
+   Copyright The containerd Authors.
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+*/
+
+package process
+
+import (
+	"context"
+	"io"
+	"time"
+
+	"github.com/containerd/console"
+	"github.com/containerd/containerd/pkg/stdio"
+)
+
+// Process on a system
+type Process interface {
+	// ID returns the id for the process
+	ID() string
+	// Pid returns the pid for the process
+	Pid() int
+	// ExitStatus returns the exit status
+	ExitStatus() int
+	// ExitedAt is the time the process exited
+	ExitedAt() time.Time
+	// Stdin returns the process STDIN
+	Stdin() io.Closer
+	// Stdio returns io information for the container
+	Stdio() stdio.Stdio
+	// Status returns the process status
+	Status(context.Context) (string, error)
+	// Wait blocks until the process has exited
+	Wait()
+	// Resize resizes the process console
+	Resize(ws console.WinSize) error
+	// Start execution of the process
+	Start(context.Context) error
+	// Delete deletes the process and its resourcess
+	Delete(context.Context) error
+	// Kill kills the process
+	Kill(context.Context, uint32, bool) error
+	// SetExited sets the exit status for the process
+	SetExited(status int)
+}