Move exec and checkpoint to process state

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

containerd-shim/main.go

@@ -12,17 +12,6 @@ import (
 	"github.com/docker/docker/pkg/term"
 )
 
-var (
-	fexec       bool
-	fcheckpoint string
-)
-
-func init() {
-	flag.BoolVar(&fexec, "exec", false, "exec a process instead of starting the init")
-	flag.StringVar(&fcheckpoint, "checkpoint", "", "start container from an existing checkpoint")
-	flag.Parse()
-}
-
 func setupLogger() {
 	f, err := os.OpenFile("/tmp/shim.log", os.O_CREATE|os.O_RDWR|os.O_APPEND, 0755)
 	if err != nil {
@@ -37,6 +26,7 @@ func setupLogger() {
 // the cwd of the shim should be the bundle for the container.  Arg1 should be the path
 // to the state directory where the shim can locate fifos and other information.
 func main() {
+	flag.Parse()
 	// start handling signals as soon as possible so that things are properly reaped
 	// or if runc exits before we hit the handler
 	signals := make(chan os.Signal, 2048)
@@ -56,7 +46,7 @@ func main() {
 		logrus.WithField("error", err).Fatal("shim: open control pipe")
 	}
 	defer control.Close()
-	p, err := newProcess(flag.Arg(0), flag.Arg(1), fexec, fcheckpoint)
+	p, err := newProcess(flag.Arg(0), flag.Arg(1))
 	if err != nil {
 		logrus.WithField("error", err).Fatal("shim: create new process")
 	}

containerd-shim/process.go

@@ -27,19 +27,18 @@ type process struct {
 	state        *runtime.ProcessState
 }
 
-func newProcess(id, bundle string, exec bool, checkpoint string) (*process, error) {
+func newProcess(id, bundle string) (*process, error) {
 	p := &process{
 		id:     id,
 		bundle: bundle,
-		exec:   exec,
 	}
 	s, err := loadProcess()
 	if err != nil {
 		return nil, err
 	}
 	p.state = s
-	if checkpoint != "" {
-		cpt, err := loadCheckpoint(bundle, checkpoint)
+	if s.Checkpoint != "" {
+		cpt, err := loadCheckpoint(bundle, s.Checkpoint)
 		if err != nil {
 			return nil, err
 		}
@@ -83,7 +82,7 @@ func (p *process) start() error {
 		return err
 	}
 	args := []string{}
-	if p.exec {
+	if p.state.Exec {
 		args = append(args, "exec",
 			"--process", filepath.Join(cwd, "process.json"),
 			"--console", p.consolePath,
@@ -146,7 +145,7 @@ func (p *process) pid() int {
 }
 
 func (p *process) delete() error {
-	if !p.exec {
+	if !p.state.Exec {
 		return exec.Command("runc", "delete", p.id).Run()
 	}
 	return nil

runtime/container.go

@@ -150,7 +150,6 @@ func (c *container) Start(checkpoint string, s Stdio) (Process, error) {
 		return nil, err
 	}
 	cmd := exec.Command("containerd-shim",
-		"-checkpoint", checkpoint,
 		c.id, c.bundle,
 	)
 	cmd.Dir = processRoot
@@ -162,6 +161,7 @@ func (c *container) Start(checkpoint string, s Stdio) (Process, error) {
 		return nil, err
 	}
 	config := &processConfig{
+		checkpoint:  checkpoint,
 		root:        processRoot,
 		id:          InitProcessID,
 		c:           c,
@@ -189,7 +189,6 @@ func (c *container) Exec(pid string, spec specs.Process, s Stdio) (Process, erro
 		return nil, err
 	}
 	cmd := exec.Command("containerd-shim",
-		"-exec",
 		c.id, c.bundle,
 	)
 	cmd.Dir = processRoot
@@ -197,6 +196,7 @@ func (c *container) Exec(pid string, spec specs.Process, s Stdio) (Process, erro
 		Setpgid: true,
 	}
 	config := &processConfig{
+		exec:        true,
 		id:          pid,
 		root:        processRoot,
 		c:           c,

runtime/process.go

@@ -47,6 +47,8 @@ type processConfig struct {
 	spec        *specs.LinuxSpec
 	c           *container
 	stdio       Stdio
+	exec        bool
+	checkpoint  string
 }
 
 func newProcess(config *processConfig) (*process, error) {
@@ -67,12 +69,14 @@ func newProcess(config *processConfig) (*process, error) {
 	}
 	defer f.Close()
 	if err := json.NewEncoder(f).Encode(ProcessState{
-		Process: config.processSpec,
-		RootUID: uid,
-		RootGID: gid,
-		Stdin:   config.stdio.Stdin,
-		Stdout:  config.stdio.Stdout,
-		Stderr:  config.stdio.Stderr,
+		Process:    config.processSpec,
+		Exec:       config.exec,
+		Checkpoint: config.checkpoint,
+		RootUID:    uid,
+		RootGID:    gid,
+		Stdin:      config.stdio.Stdin,
+		Stdout:     config.stdio.Stdout,
+		Stderr:     config.stdio.Stderr,
 	}); err != nil {
 		return nil, err
 	}

runtime/runtime.go

@@ -44,11 +44,13 @@ type state struct {
 
 type ProcessState struct {
 	specs.Process
-	RootUID int    `json:"rootUID"`
-	RootGID int    `json:"rootGID"`
-	Stdin   string `json:"containerdStdin"`
-	Stdout  string `json:"containerdStdout"`
-	Stderr  string `json:"containerdStderr"`
+	Exec       bool   `json:"exec"`
+	Checkpoint string `json:"checkpoint"`
+	RootUID    int    `json:"rootUID"`
+	RootGID    int    `json:"rootGID"`
+	Stdin      string `json:"containerdStdin"`
+	Stdout     string `json:"containerdStdout"`
+	Stderr     string `json:"containerdStderr"`
 }
 
 type Stat struct {