1 files changed, 182 insertions, 0 deletions
diff --git a/pkg/shim/proc/init_state.go b/pkg/shim/proc/init_state.go
new file mode 100644
index 000000000..0065fc385
--- /dev/null
+++ b/pkg/shim/proc/init_state.go
@@ -0,0 +1,182 @@
+// Copyright 2018 The containerd Authors.
+// Copyright 2018 The gVisor 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
+//
+//     https://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 proc
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/containerd/console"
+	"github.com/containerd/containerd/errdefs"
+	"github.com/containerd/containerd/pkg/process"
+)
+
+type initState interface {
+	Resize(console.WinSize) error
+	Start(context.Context) error
+	Delete(context.Context) error
+	Exec(context.Context, string, *ExecConfig) (process.Process, error)
+	Kill(context.Context, uint32, bool) error
+	SetExited(int)
+}
+
+type createdState struct {
+	p *Init
+}
+
+func (s *createdState) transition(name string) error {
+	switch name {
+	case "running":
+		s.p.initState = &runningState{p: s.p}
+	case "stopped":
+		s.p.initState = &stoppedState{p: s.p}
+	case "deleted":
+		s.p.initState = &deletedState{}
+	default:
+		return fmt.Errorf("invalid state transition %q to %q", stateName(s), name)
+	}
+	return nil
+}
+
+func (s *createdState) Resize(ws console.WinSize) error {
+	return s.p.resize(ws)
+}
+
+func (s *createdState) Start(ctx context.Context) error {
+	if err := s.p.start(ctx); err != nil {
+		// Containerd doesn't allow deleting container in created state.
+		// However, for gvisor, a non-root container in created state can
+		// only go to running state. If the container can't be started,
+		// it can only stay in created state, and never be deleted.
+		// To work around that, we treat non-root container in start failure
+		// state as stopped.
+		if !s.p.Sandbox {
+			s.p.io.Close()
+			s.p.setExited(internalErrorCode)
+			if err := s.transition("stopped"); err != nil {
+				panic(err)
+			}
+		}
+		return err
+	}
+	return s.transition("running")
+}
+
+func (s *createdState) Delete(ctx context.Context) error {
+	if err := s.p.delete(ctx); err != nil {
+		return err
+	}
+	return s.transition("deleted")
+}
+
+func (s *createdState) Kill(ctx context.Context, sig uint32, all bool) error {
+	return s.p.kill(ctx, sig, all)
+}
+
+func (s *createdState) SetExited(status int) {
+	s.p.setExited(status)
+
+	if err := s.transition("stopped"); err != nil {
+		panic(err)
+	}
+}
+
+func (s *createdState) Exec(ctx context.Context, path string, r *ExecConfig) (process.Process, error) {
+	return s.p.exec(path, r)
+}
+
+type runningState struct {
+	p *Init
+}
+
+func (s *runningState) transition(name string) error {
+	switch name {
+	case "stopped":
+		s.p.initState = &stoppedState{p: s.p}
+	default:
+		return fmt.Errorf("invalid state transition %q to %q", stateName(s), name)
+	}
+	return nil
+}
+
+func (s *runningState) Resize(ws console.WinSize) error {
+	return s.p.resize(ws)
+}
+
+func (s *runningState) Start(ctx context.Context) error {
+	return fmt.Errorf("cannot start a running process.ss")
+}
+
+func (s *runningState) Delete(ctx context.Context) error {
+	return fmt.Errorf("cannot delete a running process.ss")
+}
+
+func (s *runningState) Kill(ctx context.Context, sig uint32, all bool) error {
+	return s.p.kill(ctx, sig, all)
+}
+
+func (s *runningState) SetExited(status int) {
+	s.p.setExited(status)
+
+	if err := s.transition("stopped"); err != nil {
+		panic(err)
+	}
+}
+
+func (s *runningState) Exec(ctx context.Context, path string, r *ExecConfig) (process.Process, error) {
+	return s.p.exec(path, r)
+}
+
+type stoppedState struct {
+	p *Init
+}
+
+func (s *stoppedState) transition(name string) error {
+	switch name {
+	case "deleted":
+		s.p.initState = &deletedState{}
+	default:
+		return fmt.Errorf("invalid state transition %q to %q", stateName(s), name)
+	}
+	return nil
+}
+
+func (s *stoppedState) Resize(ws console.WinSize) error {
+	return fmt.Errorf("cannot resize a stopped container")
+}
+
+func (s *stoppedState) Start(ctx context.Context) error {
+	return fmt.Errorf("cannot start a stopped process.ss")
+}
+
+func (s *stoppedState) Delete(ctx context.Context) error {
+	if err := s.p.delete(ctx); err != nil {
+		return err
+	}
+	return s.transition("deleted")
+}
+
+func (s *stoppedState) Kill(ctx context.Context, sig uint32, all bool) error {
+	return errdefs.ToGRPCf(errdefs.ErrNotFound, "process.ss %s not found", s.p.id)
+}
+
+func (s *stoppedState) SetExited(status int) {
+	// no op
+}
+
+func (s *stoppedState) Exec(ctx context.Context, path string, r *ExecConfig) (process.Process, error) {
+	return nil, fmt.Errorf("cannot exec in a stopped state")
+}