Move Exec creation to init process

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

cmd/containerd-shim/main_unix.go

@@ -18,6 +18,7 @@ import (
 	"github.com/containerd/containerd/dialer"
 	"github.com/containerd/containerd/errdefs"
 	"github.com/containerd/containerd/events"
+	"github.com/containerd/containerd/linux/proc"
 	"github.com/containerd/containerd/linux/shim"
 	shimapi "github.com/containerd/containerd/linux/shim/v1"
 	"github.com/containerd/containerd/reaper"
@@ -56,7 +57,7 @@ func init() {
 	flag.StringVar(&socketFlag, "socket", "", "abstract socket path to serve")
 	flag.StringVar(&addressFlag, "address", "", "grpc address back to main containerd")
 	flag.StringVar(&workdirFlag, "workdir", "", "path used to storge large temporary data")
-	flag.StringVar(&runtimeRootFlag, "runtime-root", shim.RuncRoot, "root directory for the runtime")
+	flag.StringVar(&runtimeRootFlag, "runtime-root", proc.RuncRoot, "root directory for the runtime")
 	flag.StringVar(&criuFlag, "criu", "", "path to criu binary")
 	flag.BoolVar(&systemdCgroupFlag, "systemd-cgroup", false, "set runtime to use systemd-cgroup")
 	flag.Parse()

linux/proc/exec.go

@@ -4,7 +4,6 @@ package proc
 
 import (
 	"context"
-	"encoding/json"
 	"fmt"
 	"io"
 	"os"
@@ -16,8 +15,6 @@ import (
 	"golang.org/x/sys/unix"
 
 	"github.com/containerd/console"
-	"github.com/containerd/containerd/identifiers"
-	shimapi "github.com/containerd/containerd/linux/shim/v1"
 	"github.com/containerd/fifo"
 	runc "github.com/containerd/go-runc"
 	specs "github.com/opencontainers/runtime-spec/specs-go"
@@ -46,35 +43,6 @@ type execProcess struct {
 	waitBlock chan struct{}
 }
 
-// NewExec returns a new exec'd process
-func NewExec(context context.Context, path string, r *shimapi.ExecProcessRequest, parent *Init, id string) (Process, error) {
-	if err := identifiers.Validate(id); err != nil {
-		return nil, errors.Wrapf(err, "invalid exec id")
-	}
-	// process exec request
-	var spec specs.Process
-	if err := json.Unmarshal(r.Spec.Value, &spec); err != nil {
-		return nil, err
-	}
-	spec.Terminal = r.Terminal
-
-	e := &execProcess{
-		id:     id,
-		path:   path,
-		parent: parent,
-		spec:   spec,
-		stdio: Stdio{
-			Stdin:    r.Stdin,
-			Stdout:   r.Stdout,
-			Stderr:   r.Stderr,
-			Terminal: r.Terminal,
-		},
-		waitBlock: make(chan struct{}),
-	}
-	e.State = &execCreatedState{p: e}
-	return e, nil
-}
-
 func (e *execProcess) Wait() {
 	<-e.waitBlock
 }

linux/proc/init.go

@@ -337,6 +337,35 @@ func (p *Init) Runtime() *runc.Runc {
 	return p.runtime
 }
 
+// Exec returns a new exec'd process
+func (p *Init) Exec(context context.Context, path string, r *shimapi.ExecProcessRequest) (Process, error) {
+	if err := identifiers.Validate(r.ID); err != nil {
+		return nil, errors.Wrapf(err, "invalid exec id")
+	}
+	// process exec request
+	var spec specs.Process
+	if err := json.Unmarshal(r.Spec.Value, &spec); err != nil {
+		return nil, err
+	}
+	spec.Terminal = r.Terminal
+
+	e := &execProcess{
+		id:     r.ID,
+		path:   path,
+		parent: p,
+		spec:   spec,
+		stdio: Stdio{
+			Stdin:    r.Stdin,
+			Stdout:   r.Stdout,
+			Stderr:   r.Stderr,
+			Terminal: r.Terminal,
+		},
+		waitBlock: make(chan struct{}),
+	}
+	e.State = &execCreatedState{p: e}
+	return e, nil
+}
+
 func (p *Init) checkpoint(context context.Context, r *shimapi.CheckpointTaskRequest) error {
 	var options runctypes.CheckpointOptions
 	if r.Options != nil {

linux/runtime.go

@@ -17,8 +17,8 @@ import (
 	"github.com/containerd/containerd/errdefs"
 	"github.com/containerd/containerd/events/exchange"
 	"github.com/containerd/containerd/identifiers"
+	"github.com/containerd/containerd/linux/proc"
 	"github.com/containerd/containerd/linux/runctypes"
-	client "github.com/containerd/containerd/linux/shim"
 	shim "github.com/containerd/containerd/linux/shim/v1"
 	"github.com/containerd/containerd/log"
 	"github.com/containerd/containerd/metadata"
@@ -376,7 +376,7 @@ func (r *Runtime) loadTasks(ctx context.Context, ns string) ([]*Task, error) {
 			filepath.Join(r.state, ns, id),
 			filepath.Join(r.root, ns, id),
 		)
-		pid, _ := runc.ReadPidFile(filepath.Join(bundle.path, client.InitPidFile))
+		pid, _ := runc.ReadPidFile(filepath.Join(bundle.path, proc.InitPidFile))
 		s, err := bundle.NewShimClient(ctx, ns, ShimConnect(), nil)
 		if err != nil {
 			log.G(ctx).WithError(err).WithFields(logrus.Fields{
@@ -474,7 +474,7 @@ func (r *Runtime) getRuntime(ctx context.Context, ns, id string) (*runc.Runc, er
 
 	var (
 		cmd  = r.config.Runtime
-		root = client.RuncRoot
+		root = proc.RuncRoot
 	)
 	if ropts != nil {
 		if ropts.Runtime != "" {

linux/shim/service.go

@@ -218,7 +218,7 @@ func (s *Service) Exec(ctx context.Context, r *shimapi.ExecProcessRequest) (*goo
 		return nil, errdefs.ToGRPCf(errdefs.ErrFailedPrecondition, "container must be created")
 	}
 
-	process, err := proc.NewExec(ctx, s.config.Path, r, p.(*proc.Init), r.ID)
+	process, err := p.(*proc.Init).Exec(ctx, s.config.Path, r)
 	if err != nil {
 		return nil, errdefs.ToGRPC(err)
 	}