execution: remove statedir type

Signed-off-by: Kenfe-Mickael Laventure <mickael.laventure@gmail.com>

execution/container.go

@@ -1,91 +1,179 @@
 package execution
 
-import "fmt"
+import (
+	"context"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"sync"
 
-func NewContainer(stateRoot, id, bundle string) (*Container, error) {
-	stateDir, err := NewStateDir(stateRoot, id)
-	if err != nil {
-		return nil, err
-	}
-	return &Container{
+	"github.com/docker/containerd/log"
+	"github.com/pkg/errors"
+)
+
+const (
+	InitProcessID    = "init"
+	processesDirName = "processes"
+	bundleFileName   = "bundle"
+)
+
+func LoadContainer(ctx context.Context, stateDir, id string) (c *Container, err error) {
+	c = &Container{
 		id:        id,
-		bundle:    bundle,
 		stateDir:  stateDir,
-		status:    Created,
-		processes: make(map[string]Process),
-	}, nil
+		processes: make(map[string]Process, 1),
+		ctx:       ctx,
+		status:    Unknown,
+	}
+
+	data, err := ioutil.ReadFile(filepath.Join(stateDir, bundleFileName))
+	if err != nil {
+		err = errors.Wrapf(err, "failed to read bundle path")
+		return
+	}
+	c.bundle = string(data)
+
+	return
 }
 
-func LoadContainer(dir StateDir, id, bundle string, status Status) *Container {
-	return &Container{
+func NewContainer(ctx context.Context, stateDir, id, bundle string) (c *Container, err error) {
+	c = &Container{
 		id:        id,
-		stateDir:  dir,
+		stateDir:  stateDir,
 		bundle:    bundle,
-		status:    status,
-		processes: make(map[string]Process),
+		processes: make(map[string]Process, 1),
+		status:    Created,
+		ctx:       ctx,
 	}
+	defer func() {
+		if err != nil {
+			c.Cleanup()
+			c = nil
+		}
+	}()
+
+	if err = os.Mkdir(stateDir, 0700); err != nil {
+		err = errors.Wrap(err, "failed to create container state dir")
+		return
+	}
+
+	bundleFile := filepath.Join(stateDir, bundleFileName)
+	if err = ioutil.WriteFile(bundleFile, []byte(bundle), 0600); err != nil {
+		err = errors.Wrap(err, "failed to store bundle path")
+		return
+	}
+
+	processesDir := filepath.Join(stateDir, processesDirName)
+	if err = os.Mkdir(processesDir, 0700); err != nil {
+		err = errors.Wrap(err, "failed to create processes statedir")
+		return
+	}
+
+	return
 }
 
 type Container struct {
-	id       string
-	bundle   string
-	stateDir StateDir
-	initPid  int64
-	status   Status
-
+	id        string
+	stateDir  string
+	bundle    string
 	processes map[string]Process
+	status    Status
+
+	ctx context.Context
+	mu  sync.Mutex
 }
 
 func (c *Container) ID() string {
 	return c.id
 }
 
-func (c *Container) Status() Status {
-	for _, p := range c.processes {
-		if p.Pid() == c.initPid {
-			c.status = p.Status()
-			break
-		}
-	}
-	return c.status
-}
-
 func (c *Container) Bundle() string {
 	return c.bundle
 }
 
-func (c *Container) StateDir() StateDir {
-	return c.stateDir
-}
-
 func (c *Container) Wait() (uint32, error) {
-	for _, p := range c.processes {
-		if p.Pid() == c.initPid {
-			return p.Wait()
-		}
-	}
-	return 0, fmt.Errorf("no init process")
+	initProcess := c.GetProcess(InitProcessID)
+	return initProcess.Wait()
 }
 
-func (c *Container) AddProcess(p Process, isInit bool) {
-	if isInit {
-		c.initPid = p.Pid()
-	}
+func (c *Container) Status() Status {
+	initProcess := c.GetProcess(InitProcessID)
+	return initProcess.Status()
+}
+
+func (c *Container) AddProcess(p Process) {
+	c.mu.Lock()
 	c.processes[p.ID()] = p
+	c.mu.Unlock()
+}
+
+func (c *Container) RemoveProcess(id string) error {
+	if _, ok := c.processes[id]; !ok {
+		return errors.Errorf("no such process %s", id)
+	}
+
+	c.mu.Lock()
+	delete(c.processes, id)
+	c.mu.Unlock()
+
+	processStateDir := filepath.Join(c.stateDir, processesDirName, id)
+	err := os.RemoveAll(processStateDir)
+	if err != nil {
+		return errors.Wrap(err, "failed to remove process state dir")
+	}
+
+	return nil
 }
 
 func (c *Container) GetProcess(id string) Process {
+	c.mu.Lock()
+	defer c.mu.Unlock()
 	return c.processes[id]
 }
 
-func (c *Container) RemoveProcess(id string) {
-	delete(c.processes, id)
+func (c *Container) Processes() []Process {
+	var procs []Process
+
+	c.mu.Lock()
+	for _, p := range c.processes {
+		procs = append(procs, p)
+	}
+	c.mu.Unlock()
+
+	return procs
 }
 
-func (c *Container) Processes() []Process {
-	var out []Process
-	for _, p := range c.processes {
-		out = append(out, p)
-	}
-	return out
+// ProcessStateDir returns the path of the state dir for a given
+// process id. The process doesn't have to exist for this to succeed.
+func (c *Container) ProcessStateDir(id string) string {
+	return filepath.Join(c.stateDir, processesDirName, id)
+}
+
+// ProcessesStateDir returns a map matching process ids to their state
+// directory
+func (c *Container) ProcessesStateDir() (map[string]string, error) {
+	root := filepath.Join(c.stateDir, processesDirName)
+	dirs, err := ioutil.ReadDir(root)
+	if err != nil {
+		return nil, errors.Wrapf(err, "failed to list processes state dirs")
+	}
+
+	procs := make(map[string]string, 1)
+	for _, d := range dirs {
+		if d.IsDir() {
+			procs[d.Name()] = filepath.Join(root, d.Name())
+		}
+	}
+
+	return procs, nil
+}
+
+func (c *Container) Cleanup() {
+	if err := os.RemoveAll(c.stateDir); err != nil {
+		log.G(c.ctx).Warnf("failed to remove container state dir: %v", err)
+	}
+}
+
+func (c *Container) Context() context.Context {
+	return c.ctx
 }